| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| Jan Kara | 4849 | 18.41% | 116 | 15.34% |
| zhangyi (F) | 3874 | 14.71% | 29 | 3.84% |
| Dave Kleikamp | 2901 | 11.02% | 2 | 0.26% |
| Theodore Y. Ts'o | 2164 | 8.22% | 131 | 17.33% |
| Amir Goldstein | 1930 | 7.33% | 4 | 0.53% |
| Aneesh Kumar K.V | 817 | 3.10% | 41 | 5.42% |
| Matthew Wilcox | 649 | 2.46% | 35 | 4.63% |
| Lukas Czerner | 634 | 2.41% | 19 | 2.51% |
| Matthew Bobrowski | 526 | 2.00% | 5 | 0.66% |
| Darrick J. Wong | 519 | 1.97% | 8 | 1.06% |
| Mingming Cao | 477 | 1.81% | 14 | 1.85% |
| Ritesh Harjani | 467 | 1.77% | 17 | 2.25% |
| Zheng Liu | 454 | 1.72% | 12 | 1.59% |
| Dmitriy Monakhov | 392 | 1.49% | 18 | 2.38% |
| Michael Halcrow | 391 | 1.48% | 3 | 0.40% |
| Harshad Shirwadkar | 335 | 1.27% | 8 | 1.06% |
| Eric Biggers | 325 | 1.23% | 17 | 2.25% |
| Ross Zwisler | 307 | 1.17% | 7 | 0.93% |
| Miao Xie | 296 | 1.12% | 4 | 0.53% |
| Tao Ma | 265 | 1.01% | 9 | 1.19% |
| Tahsin Erdogan | 244 | 0.93% | 7 | 0.93% |
| Alex Tomas | 231 | 0.88% | 3 | 0.40% |
| David Howells | 225 | 0.85% | 5 | 0.66% |
| Liu Song | 179 | 0.68% | 2 | 0.26% |
| Kalpak Shah | 165 | 0.63% | 2 | 0.26% |
| Daeho Jeong | 148 | 0.56% | 5 | 0.66% |
| Frank Mayhar | 140 | 0.53% | 4 | 0.53% |
| Baokun Li | 140 | 0.53% | 7 | 0.93% |
| Eric Whitney | 130 | 0.49% | 7 | 0.93% |
| Christoph Hellwig | 121 | 0.46% | 21 | 2.78% |
| Dan J Williams | 117 | 0.44% | 1 | 0.13% |
| Andi Kleen | 104 | 0.39% | 2 | 0.26% |
| Chandan Rajendra | 86 | 0.33% | 5 | 0.66% |
| Eric Sandeen | 80 | 0.30% | 12 | 1.59% |
| Mauricio Faria de Oliveira | 77 | 0.29% | 2 | 0.26% |
| Allison Henderson | 73 | 0.28% | 4 | 0.53% |
| Ye Bin | 65 | 0.25% | 4 | 0.53% |
| Xiaoguang Wang | 62 | 0.24% | 2 | 0.26% |
| Jeff Layton | 60 | 0.23% | 6 | 0.79% |
| Nicholas Piggin | 58 | 0.22% | 4 | 0.53% |
| Aditya Kali | 53 | 0.20% | 3 | 0.40% |
| Christian Brauner | 50 | 0.19% | 12 | 1.59% |
| Eryu Guan | 49 | 0.19% | 5 | 0.66% |
| Vishal Moola (Oracle) | 49 | 0.19% | 1 | 0.13% |
| Andreas Dilger | 48 | 0.18% | 3 | 0.40% |
| Josef Bacik | 46 | 0.17% | 1 | 0.13% |
| Jean Noel Cordenner | 43 | 0.16% | 1 | 0.13% |
| Thiemo Nagel | 42 | 0.16% | 1 | 0.13% |
| Li Xi | 41 | 0.16% | 1 | 0.13% |
| Al Viro | 41 | 0.16% | 8 | 1.06% |
| Linus Torvalds | 38 | 0.14% | 6 | 0.79% |
| Jiaying Zhang | 36 | 0.14% | 2 | 0.26% |
| Ira Weiny | 33 | 0.13% | 4 | 0.53% |
| Yongqiang Yang | 31 | 0.12% | 4 | 0.53% |
| Tadeusz Struk | 29 | 0.11% | 1 | 0.13% |
| Ojaswin Mujoo | 28 | 0.11% | 2 | 0.26% |
| Ming Lei | 27 | 0.10% | 2 | 0.26% |
| Kirill A. Shutemov | 26 | 0.10% | 1 | 0.13% |
| Xin Yin | 26 | 0.10% | 3 | 0.40% |
| yangerkun | 25 | 0.09% | 2 | 0.26% |
| Wojciech Gładysz | 22 | 0.08% | 1 | 0.13% |
| Luis R. Rodriguez | 21 | 0.08% | 1 | 0.13% |
| zhengliang | 20 | 0.08% | 1 | 0.13% |
| Jinke Han | 19 | 0.07% | 1 | 0.13% |
| Eric W. Biedermann | 19 | 0.07% | 1 | 0.13% |
| Duane Griffin | 19 | 0.07% | 2 | 0.26% |
| Badari Pulavarty | 19 | 0.07% | 1 | 0.13% |
| Curt Wohlgemuth | 18 | 0.07% | 5 | 0.66% |
| Zhihao Cheng | 17 | 0.06% | 1 | 0.13% |
| liang xie | 16 | 0.06% | 1 | 0.13% |
| Shaohua Li | 16 | 0.06% | 1 | 0.13% |
| Amit Arora | 15 | 0.06% | 1 | 0.13% |
| Kazuya Mio | 15 | 0.06% | 1 | 0.13% |
| Andrea Righi | 15 | 0.06% | 1 | 0.13% |
| Anatol Pomozov | 14 | 0.05% | 3 | 0.40% |
| Souptick Joarder | 13 | 0.05% | 1 | 0.13% |
| Namjae Jeon | 12 | 0.05% | 2 | 0.26% |
| Valerie Clement | 10 | 0.04% | 1 | 0.13% |
| Dave Jiang | 10 | 0.04% | 2 | 0.26% |
| Toshi Kani | 9 | 0.03% | 2 | 0.26% |
| Vasily Averin | 9 | 0.03% | 1 | 0.13% |
| Arnd Bergmann | 8 | 0.03% | 2 | 0.26% |
| wangguang | 8 | 0.03% | 1 | 0.13% |
| Linus Torvalds (pre-git) | 7 | 0.03% | 3 | 0.40% |
| Mel Gorman | 7 | 0.03% | 1 | 0.13% |
| Luo Meng | 7 | 0.03% | 1 | 0.13% |
| Gabriel Krisman Bertazi | 6 | 0.02% | 1 | 0.13% |
| Michael Christie | 6 | 0.02% | 2 | 0.26% |
| Namhyung Kim | 6 | 0.02% | 1 | 0.13% |
| Fabian Frederick | 6 | 0.02% | 1 | 0.13% |
| Hisashi Hifumi | 5 | 0.02% | 1 | 0.13% |
| Andrew Morton | 5 | 0.02% | 2 | 0.26% |
| Uros Bizjak | 5 | 0.02% | 1 | 0.13% |
| Konstantin Khlebnikov | 5 | 0.02% | 1 | 0.13% |
| Goldwyn Rodrigues | 5 | 0.02% | 1 | 0.13% |
| Hongnan Li | 4 | 0.02% | 1 | 0.13% |
| Shilong Wang | 4 | 0.02% | 2 | 0.26% |
| David Gstir | 4 | 0.02% | 1 | 0.13% |
| Carlos Maiolino | 4 | 0.02% | 1 | 0.13% |
| Jon Ernst | 4 | 0.02% | 1 | 0.13% |
| Maxim Patlasov | 4 | 0.02% | 1 | 0.13% |
| Qian Cai | 3 | 0.01% | 1 | 0.13% |
| Shijie Luo | 3 | 0.01% | 1 | 0.13% |
| Dr. Tilmann Bubeck | 3 | 0.01% | 1 | 0.13% |
| Dan Carpenter | 3 | 0.01% | 1 | 0.13% |
| Michal Hocko | 3 | 0.01% | 1 | 0.13% |
| Chunguang Xu | 3 | 0.01% | 1 | 0.13% |
| Andreas Gruenbacher | 3 | 0.01% | 1 | 0.13% |
| Omar Sandoval | 2 | 0.01% | 1 | 0.13% |
| Jaegeuk Kim | 2 | 0.01% | 1 | 0.13% |
| Pan Bian | 2 | 0.01% | 1 | 0.13% |
| Julia Lawall | 2 | 0.01% | 1 | 0.13% |
| Nikolay Borisov | 2 | 0.01% | 1 | 0.13% |
| SeungHun Lee | 2 | 0.01% | 1 | 0.13% |
| Miklos Szeredi | 2 | 0.01% | 1 | 0.13% |
| Leah Rumancik | 2 | 0.01% | 1 | 0.13% |
| Cheng Nie | 2 | 0.01% | 1 | 0.13% |
| Sidhartha Kumar | 2 | 0.01% | 1 | 0.13% |
| Johannes Weiner | 2 | 0.01% | 1 | 0.13% |
| chenyichong | 1 | 0.00% | 1 | 0.13% |
| Stephen Hemminger | 1 | 0.00% | 1 | 0.13% |
| Artem B. Bityutskiy | 1 | 0.00% | 1 | 0.13% |
| Vivek Goyal | 1 | 0.00% | 1 | 0.13% |
| Li Zefan | 1 | 0.00% | 1 | 0.13% |
| ZhangXiaoxu | 1 | 0.00% | 1 | 0.13% |
| Akinobu Mita | 1 | 0.00% | 1 | 0.13% |
| Justin P. Mattock | 1 | 0.00% | 1 | 0.13% |
| Eric Dumazet | 1 | 0.00% | 1 | 0.13% |
| Alexandre Ratchov | 1 | 0.00% | 1 | 0.13% |
| Bhaskar Chowdhury | 1 | 0.00% | 1 | 0.13% |
| Randy Dunlap | 1 | 0.00% | 1 | 0.13% |
| Greg Kroah-Hartman | 1 | 0.00% | 1 | 0.13% |
| Lucas De Marchi | 1 | 0.00% | 1 | 0.13% |
| Total | 26333 | 756 |
// SPDX-License-Identifier: GPL-2.0 /* * linux/fs/ext4/inode.c * * Copyright (C) 1992, 1993, 1994, 1995 * Remy Card (card@masi.ibp.fr) * Laboratoire MASI - Institut Blaise Pascal * Universite Pierre et Marie Curie (Paris VI) * * from * * linux/fs/minix/inode.c * * Copyright (C) 1991, 1992 Linus Torvalds * * 64-bit file support on 64-bit platforms by Jakub Jelinek * (jj@sunsite.ms.mff.cuni.cz) * * Assorted race fixes, rewrite of ext4_get_block() by Al Viro, 2000 */ #include <linux/fs.h> #include <linux/mount.h> #include <linux/time.h> #include <linux/highuid.h> #include <linux/pagemap.h> #include <linux/dax.h> #include <linux/quotaops.h> #include <linux/string.h> #include <linux/buffer_head.h> #include <linux/writeback.h> #include <linux/pagevec.h> #include <linux/mpage.h> #include <linux/namei.h> #include <linux/uio.h> #include <linux/bio.h> #include <linux/workqueue.h> #include <linux/kernel.h> #include <linux/printk.h> #include <linux/slab.h> #include <linux/bitops.h> #include <linux/iomap.h> #include <linux/iversion.h> #include "ext4_jbd2.h" #include "xattr.h" #include "acl.h" #include "truncate.h" #include <trace/events/ext4.h> static __u32 ext4_inode_csum(struct inode *inode, struct ext4_inode *raw, struct ext4_inode_info *ei) { struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); __u32 csum; __u16 dummy_csum = 0; int offset = offsetof(struct ext4_inode, i_checksum_lo); unsigned int csum_size = sizeof(dummy_csum); csum = ext4_chksum(sbi, ei->i_csum_seed, (__u8 *)raw, offset); csum = ext4_chksum(sbi, csum, (__u8 *)&dummy_csum, csum_size); offset += csum_size; csum = ext4_chksum(sbi, csum, (__u8 *)raw + offset, EXT4_GOOD_OLD_INODE_SIZE - offset); if (EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE) { offset = offsetof(struct ext4_inode, i_checksum_hi); csum = ext4_chksum(sbi, csum, (__u8 *)raw + EXT4_GOOD_OLD_INODE_SIZE, offset - EXT4_GOOD_OLD_INODE_SIZE); if (EXT4_FITS_IN_INODE(raw, ei, i_checksum_hi)) { csum = ext4_chksum(sbi, csum, (__u8 *)&dummy_csum, csum_size); offset += csum_size; } csum = ext4_chksum(sbi, csum, (__u8 *)raw + offset, EXT4_INODE_SIZE(inode->i_sb) - offset); } return csum; } static int ext4_inode_csum_verify(struct inode *inode, struct ext4_inode *raw, struct ext4_inode_info *ei) { __u32 provided, calculated; if (EXT4_SB(inode->i_sb)->s_es->s_creator_os != cpu_to_le32(EXT4_OS_LINUX) || !ext4_has_metadata_csum(inode->i_sb)) return 1; provided = le16_to_cpu(raw->i_checksum_lo); calculated = ext4_inode_csum(inode, raw, ei); if (EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE && EXT4_FITS_IN_INODE(raw, ei, i_checksum_hi)) provided |= ((__u32)le16_to_cpu(raw->i_checksum_hi)) << 16; else calculated &= 0xFFFF; return provided == calculated; } void ext4_inode_csum_set(struct inode *inode, struct ext4_inode *raw, struct ext4_inode_info *ei) { __u32 csum; if (EXT4_SB(inode->i_sb)->s_es->s_creator_os != cpu_to_le32(EXT4_OS_LINUX) || !ext4_has_metadata_csum(inode->i_sb)) return; csum = ext4_inode_csum(inode, raw, ei); raw->i_checksum_lo = cpu_to_le16(csum & 0xFFFF); if (EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE && EXT4_FITS_IN_INODE(raw, ei, i_checksum_hi)) raw->i_checksum_hi = cpu_to_le16(csum >> 16); } static inline int ext4_begin_ordered_truncate(struct inode *inode, loff_t new_size) { trace_ext4_begin_ordered_truncate(inode, new_size); /* * If jinode is zero, then we never opened the file for * writing, so there's no need to call * jbd2_journal_begin_ordered_truncate() since there's no * outstanding writes we need to flush. */ if (!EXT4_I(inode)->jinode) return 0; return jbd2_journal_begin_ordered_truncate(EXT4_JOURNAL(inode), EXT4_I(inode)->jinode, new_size); } static int ext4_meta_trans_blocks(struct inode *inode, int lblocks, int pextents); /* * Test whether an inode is a fast symlink. * A fast symlink has its symlink data stored in ext4_inode_info->i_data. */ int ext4_inode_is_fast_symlink(struct inode *inode) { if (!(EXT4_I(inode)->i_flags & EXT4_EA_INODE_FL)) { int ea_blocks = EXT4_I(inode)->i_file_acl ? EXT4_CLUSTER_SIZE(inode->i_sb) >> 9 : 0; if (ext4_has_inline_data(inode)) return 0; return (S_ISLNK(inode->i_mode) && inode->i_blocks - ea_blocks == 0); } return S_ISLNK(inode->i_mode) && inode->i_size && (inode->i_size < EXT4_N_BLOCKS * 4); } /* * Called at the last iput() if i_nlink is zero. */ void ext4_evict_inode(struct inode *inode) { handle_t *handle; int err; /* * Credits for final inode cleanup and freeing: * sb + inode (ext4_orphan_del()), block bitmap, group descriptor * (xattr block freeing), bitmap, group descriptor (inode freeing) */ int extra_credits = 6; struct ext4_xattr_inode_array *ea_inode_array = NULL; bool freeze_protected = false; trace_ext4_evict_inode(inode); if (EXT4_I(inode)->i_flags & EXT4_EA_INODE_FL) ext4_evict_ea_inode(inode); if (inode->i_nlink) { truncate_inode_pages_final(&inode->i_data); goto no_delete; } if (is_bad_inode(inode)) goto no_delete; dquot_initialize(inode); if (ext4_should_order_data(inode)) ext4_begin_ordered_truncate(inode, 0); truncate_inode_pages_final(&inode->i_data); /* * For inodes with journalled data, transaction commit could have * dirtied the inode. And for inodes with dioread_nolock, unwritten * extents converting worker could merge extents and also have dirtied * the inode. Flush worker is ignoring it because of I_FREEING flag but * we still need to remove the inode from the writeback lists. */ if (!list_empty_careful(&inode->i_io_list)) inode_io_list_del(inode); /* * Protect us against freezing - iput() caller didn't have to have any * protection against it. When we are in a running transaction though, * we are already protected against freezing and we cannot grab further * protection due to lock ordering constraints. */ if (!ext4_journal_current_handle()) { sb_start_intwrite(inode->i_sb); freeze_protected = true; } if (!IS_NOQUOTA(inode)) extra_credits += EXT4_MAXQUOTAS_DEL_BLOCKS(inode->i_sb); /* * Block bitmap, group descriptor, and inode are accounted in both * ext4_blocks_for_truncate() and extra_credits. So subtract 3. */ handle = ext4_journal_start(inode, EXT4_HT_TRUNCATE, ext4_blocks_for_truncate(inode) + extra_credits - 3); if (IS_ERR(handle)) { ext4_std_error(inode->i_sb, PTR_ERR(handle)); /* * If we're going to skip the normal cleanup, we still need to * make sure that the in-core orphan linked list is properly * cleaned up. */ ext4_orphan_del(NULL, inode); if (freeze_protected) sb_end_intwrite(inode->i_sb); goto no_delete; } if (IS_SYNC(inode)) ext4_handle_sync(handle); /* * Set inode->i_size to 0 before calling ext4_truncate(). We need * special handling of symlinks here because i_size is used to * determine whether ext4_inode_info->i_data contains symlink data or * block mappings. Setting i_size to 0 will remove its fast symlink * status. Erase i_data so that it becomes a valid empty block map. */ if (ext4_inode_is_fast_symlink(inode)) memset(EXT4_I(inode)->i_data, 0, sizeof(EXT4_I(inode)->i_data)); inode->i_size = 0; err = ext4_mark_inode_dirty(handle, inode); if (err) { ext4_warning(inode->i_sb, "couldn't mark inode dirty (err %d)", err); goto stop_handle; } if (inode->i_blocks) { err = ext4_truncate(inode); if (err) { ext4_error_err(inode->i_sb, -err, "couldn't truncate inode %lu (err %d)", inode->i_ino, err); goto stop_handle; } } /* Remove xattr references. */ err = ext4_xattr_delete_inode(handle, inode, &ea_inode_array, extra_credits); if (err) { ext4_warning(inode->i_sb, "xattr delete (err %d)", err); stop_handle: ext4_journal_stop(handle); ext4_orphan_del(NULL, inode); if (freeze_protected) sb_end_intwrite(inode->i_sb); ext4_xattr_inode_array_free(ea_inode_array); goto no_delete; } /* * Kill off the orphan record which ext4_truncate created. * AKPM: I think this can be inside the above `if'. * Note that ext4_orphan_del() has to be able to cope with the * deletion of a non-existent orphan - this is because we don't * know if ext4_truncate() actually created an orphan record. * (Well, we could do this if we need to, but heck - it works) */ ext4_orphan_del(handle, inode); EXT4_I(inode)->i_dtime = (__u32)ktime_get_real_seconds(); /* * One subtle ordering requirement: if anything has gone wrong * (transaction abort, IO errors, whatever), then we can still * do these next steps (the fs will already have been marked as * having errors), but we can't free the inode if the mark_dirty * fails. */ if (ext4_mark_inode_dirty(handle, inode)) /* If that failed, just do the required in-core inode clear. */ ext4_clear_inode(inode); else ext4_free_inode(handle, inode); ext4_journal_stop(handle); if (freeze_protected) sb_end_intwrite(inode->i_sb); ext4_xattr_inode_array_free(ea_inode_array); return; no_delete: /* * Check out some where else accidentally dirty the evicting inode, * which may probably cause inode use-after-free issues later. */ WARN_ON_ONCE(!list_empty_careful(&inode->i_io_list)); if (!list_empty(&EXT4_I(inode)->i_fc_list)) ext4_fc_mark_ineligible(inode->i_sb, EXT4_FC_REASON_NOMEM, NULL); ext4_clear_inode(inode); /* We must guarantee clearing of inode... */ } #ifdef CONFIG_QUOTA qsize_t *ext4_get_reserved_space(struct inode *inode) { return &EXT4_I(inode)->i_reserved_quota; } #endif /* * Called with i_data_sem down, which is important since we can call * ext4_discard_preallocations() from here. */ void ext4_da_update_reserve_space(struct inode *inode, int used, int quota_claim) { struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); struct ext4_inode_info *ei = EXT4_I(inode); spin_lock(&ei->i_block_reservation_lock); trace_ext4_da_update_reserve_space(inode, used, quota_claim); if (unlikely(used > ei->i_reserved_data_blocks)) { ext4_warning(inode->i_sb, "%s: ino %lu, used %d " "with only %d reserved data blocks", __func__, inode->i_ino, used, ei->i_reserved_data_blocks); WARN_ON(1); used = ei->i_reserved_data_blocks; } /* Update per-inode reservations */ ei->i_reserved_data_blocks -= used; percpu_counter_sub(&sbi->s_dirtyclusters_counter, used); spin_unlock(&ei->i_block_reservation_lock); /* Update quota subsystem for data blocks */ if (quota_claim) dquot_claim_block(inode, EXT4_C2B(sbi, used)); else { /* * We did fallocate with an offset that is already delayed * allocated. So on delayed allocated writeback we should * not re-claim the quota for fallocated blocks. */ dquot_release_reservation_block(inode, EXT4_C2B(sbi, used)); } /* * If we have done all the pending block allocations and if * there aren't any writers on the inode, we can discard the * inode's preallocations. */ if ((ei->i_reserved_data_blocks == 0) && !inode_is_open_for_write(inode)) ext4_discard_preallocations(inode); } static int __check_block_validity(struct inode *inode, const char *func, unsigned int line, struct ext4_map_blocks *map) { if (ext4_has_feature_journal(inode->i_sb) && (inode->i_ino == le32_to_cpu(EXT4_SB(inode->i_sb)->s_es->s_journal_inum))) return 0; if (!ext4_inode_block_valid(inode, map->m_pblk, map->m_len)) { ext4_error_inode(inode, func, line, map->m_pblk, "lblock %lu mapped to illegal pblock %llu " "(length %d)", (unsigned long) map->m_lblk, map->m_pblk, map->m_len); return -EFSCORRUPTED; } return 0; } int ext4_issue_zeroout(struct inode *inode, ext4_lblk_t lblk, ext4_fsblk_t pblk, ext4_lblk_t len) { int ret; if (IS_ENCRYPTED(inode) && S_ISREG(inode->i_mode)) return fscrypt_zeroout_range(inode, lblk, pblk, len); ret = sb_issue_zeroout(inode->i_sb, pblk, len, GFP_NOFS); if (ret > 0) ret = 0; return ret; } #define check_block_validity(inode, map) \ __check_block_validity((inode), __func__, __LINE__, (map)) #ifdef ES_AGGRESSIVE_TEST static void ext4_map_blocks_es_recheck(handle_t *handle, struct inode *inode, struct ext4_map_blocks *es_map, struct ext4_map_blocks *map, int flags) { int retval; map->m_flags = 0; /* * There is a race window that the result is not the same. * e.g. xfstests #223 when dioread_nolock enables. The reason * is that we lookup a block mapping in extent status tree with * out taking i_data_sem. So at the time the unwritten extent * could be converted. */ down_read(&EXT4_I(inode)->i_data_sem); if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) { retval = ext4_ext_map_blocks(handle, inode, map, 0); } else { retval = ext4_ind_map_blocks(handle, inode, map, 0); } up_read((&EXT4_I(inode)->i_data_sem)); /* * We don't check m_len because extent will be collpased in status * tree. So the m_len might not equal. */ if (es_map->m_lblk != map->m_lblk || es_map->m_flags != map->m_flags || es_map->m_pblk != map->m_pblk) { printk("ES cache assertion failed for inode: %lu " "es_cached ex [%d/%d/%llu/%x] != " "found ex [%d/%d/%llu/%x] retval %d flags %x\n", inode->i_ino, es_map->m_lblk, es_map->m_len, es_map->m_pblk, es_map->m_flags, map->m_lblk, map->m_len, map->m_pblk, map->m_flags, retval, flags); } } #endif /* ES_AGGRESSIVE_TEST */ static int ext4_map_query_blocks(handle_t *handle, struct inode *inode, struct ext4_map_blocks *map) { unsigned int status; int retval; if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) retval = ext4_ext_map_blocks(handle, inode, map, 0); else retval = ext4_ind_map_blocks(handle, inode, map, 0); if (retval <= 0) return retval; if (unlikely(retval != map->m_len)) { ext4_warning(inode->i_sb, "ES len assertion failed for inode " "%lu: retval %d != map->m_len %d", inode->i_ino, retval, map->m_len); WARN_ON(1); } status = map->m_flags & EXT4_MAP_UNWRITTEN ? EXTENT_STATUS_UNWRITTEN : EXTENT_STATUS_WRITTEN; ext4_es_insert_extent(inode, map->m_lblk, map->m_len, map->m_pblk, status); return retval; } /* * The ext4_map_blocks() function tries to look up the requested blocks, * and returns if the blocks are already mapped. * * Otherwise it takes the write lock of the i_data_sem and allocate blocks * and store the allocated blocks in the result buffer head and mark it * mapped. * * If file type is extents based, it will call ext4_ext_map_blocks(), * Otherwise, call with ext4_ind_map_blocks() to handle indirect mapping * based files * * On success, it returns the number of blocks being mapped or allocated. * If flags doesn't contain EXT4_GET_BLOCKS_CREATE the blocks are * pre-allocated and unwritten, the resulting @map is marked as unwritten. * If the flags contain EXT4_GET_BLOCKS_CREATE, it will mark @map as mapped. * * It returns 0 if plain look up failed (blocks have not been allocated), in * that case, @map is returned as unmapped but we still do fill map->m_len to * indicate the length of a hole starting at map->m_lblk. * * It returns the error in case of allocation failure. */ int ext4_map_blocks(handle_t *handle, struct inode *inode, struct ext4_map_blocks *map, int flags) { struct extent_status es; int retval; int ret = 0; #ifdef ES_AGGRESSIVE_TEST struct ext4_map_blocks orig_map; memcpy(&orig_map, map, sizeof(*map)); #endif map->m_flags = 0; ext_debug(inode, "flag 0x%x, max_blocks %u, logical block %lu\n", flags, map->m_len, (unsigned long) map->m_lblk); /* * ext4_map_blocks returns an int, and m_len is an unsigned int */ if (unlikely(map->m_len > INT_MAX)) map->m_len = INT_MAX; /* We can handle the block number less than EXT_MAX_BLOCKS */ if (unlikely(map->m_lblk >= EXT_MAX_BLOCKS)) return -EFSCORRUPTED; /* Lookup extent status tree firstly */ if (!(EXT4_SB(inode->i_sb)->s_mount_state & EXT4_FC_REPLAY) && ext4_es_lookup_extent(inode, map->m_lblk, NULL, &es)) { if (ext4_es_is_written(&es) || ext4_es_is_unwritten(&es)) { map->m_pblk = ext4_es_pblock(&es) + map->m_lblk - es.es_lblk; map->m_flags |= ext4_es_is_written(&es) ? EXT4_MAP_MAPPED : EXT4_MAP_UNWRITTEN; retval = es.es_len - (map->m_lblk - es.es_lblk); if (retval > map->m_len) retval = map->m_len; map->m_len = retval; } else if (ext4_es_is_delayed(&es) || ext4_es_is_hole(&es)) { map->m_pblk = 0; map->m_flags |= ext4_es_is_delayed(&es) ? EXT4_MAP_DELAYED : 0; retval = es.es_len - (map->m_lblk - es.es_lblk); if (retval > map->m_len) retval = map->m_len; map->m_len = retval; retval = 0; } else { BUG(); } if (flags & EXT4_GET_BLOCKS_CACHED_NOWAIT) return retval; #ifdef ES_AGGRESSIVE_TEST ext4_map_blocks_es_recheck(handle, inode, map, &orig_map, flags); #endif goto found; } /* * In the query cache no-wait mode, nothing we can do more if we * cannot find extent in the cache. */ if (flags & EXT4_GET_BLOCKS_CACHED_NOWAIT) return 0; /* * Try to see if we can get the block without requesting a new * file system block. */ down_read(&EXT4_I(inode)->i_data_sem); if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) { retval = ext4_ext_map_blocks(handle, inode, map, 0); } else { retval = ext4_ind_map_blocks(handle, inode, map, 0); } if (retval > 0) { unsigned int status; if (unlikely(retval != map->m_len)) { ext4_warning(inode->i_sb, "ES len assertion failed for inode " "%lu: retval %d != map->m_len %d", inode->i_ino, retval, map->m_len); WARN_ON(1); } status = map->m_flags & EXT4_MAP_UNWRITTEN ? EXTENT_STATUS_UNWRITTEN : EXTENT_STATUS_WRITTEN; if (!(flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE) && !(status & EXTENT_STATUS_WRITTEN) && ext4_es_scan_range(inode, &ext4_es_is_delayed, map->m_lblk, map->m_lblk + map->m_len - 1)) status |= EXTENT_STATUS_DELAYED; ext4_es_insert_extent(inode, map->m_lblk, map->m_len, map->m_pblk, status); } up_read((&EXT4_I(inode)->i_data_sem)); found: if (retval > 0 && map->m_flags & EXT4_MAP_MAPPED) { ret = check_block_validity(inode, map); if (ret != 0) return ret; } /* If it is only a block(s) look up */ if ((flags & EXT4_GET_BLOCKS_CREATE) == 0) return retval; /* * Returns if the blocks have already allocated * * Note that if blocks have been preallocated * ext4_ext_map_blocks() returns with buffer head unmapped */ if (retval > 0 && map->m_flags & EXT4_MAP_MAPPED) /* * If we need to convert extent to unwritten * we continue and do the actual work in * ext4_ext_map_blocks() */ if (!(flags & EXT4_GET_BLOCKS_CONVERT_UNWRITTEN)) return retval; /* * Here we clear m_flags because after allocating an new extent, * it will be set again. */ map->m_flags &= ~EXT4_MAP_FLAGS; /* * New blocks allocate and/or writing to unwritten extent * will possibly result in updating i_data, so we take * the write lock of i_data_sem, and call get_block() * with create == 1 flag. */ down_write(&EXT4_I(inode)->i_data_sem); /* * We need to check for EXT4 here because migrate * could have changed the inode type in between */ if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) { retval = ext4_ext_map_blocks(handle, inode, map, flags); } else { retval = ext4_ind_map_blocks(handle, inode, map, flags); if (retval > 0 && map->m_flags & EXT4_MAP_NEW) { /* * We allocated new blocks which will result in * i_data's format changing. Force the migrate * to fail by clearing migrate flags */ ext4_clear_inode_state(inode, EXT4_STATE_EXT_MIGRATE); } } if (retval > 0) { unsigned int status; if (unlikely(retval != map->m_len)) { ext4_warning(inode->i_sb, "ES len assertion failed for inode " "%lu: retval %d != map->m_len %d", inode->i_ino, retval, map->m_len); WARN_ON(1); } /* * We have to zeroout blocks before inserting them into extent * status tree. Otherwise someone could look them up there and * use them before they are really zeroed. We also have to * unmap metadata before zeroing as otherwise writeback can * overwrite zeros with stale data from block device. */ if (flags & EXT4_GET_BLOCKS_ZERO && map->m_flags & EXT4_MAP_MAPPED && map->m_flags & EXT4_MAP_NEW) { ret = ext4_issue_zeroout(inode, map->m_lblk, map->m_pblk, map->m_len); if (ret) { retval = ret; goto out_sem; } } /* * If the extent has been zeroed out, we don't need to update * extent status tree. */ if ((flags & EXT4_GET_BLOCKS_PRE_IO) && ext4_es_lookup_extent(inode, map->m_lblk, NULL, &es)) { if (ext4_es_is_written(&es)) goto out_sem; } status = map->m_flags & EXT4_MAP_UNWRITTEN ? EXTENT_STATUS_UNWRITTEN : EXTENT_STATUS_WRITTEN; if (!(flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE) && !(status & EXTENT_STATUS_WRITTEN) && ext4_es_scan_range(inode, &ext4_es_is_delayed, map->m_lblk, map->m_lblk + map->m_len - 1)) status |= EXTENT_STATUS_DELAYED; ext4_es_insert_extent(inode, map->m_lblk, map->m_len, map->m_pblk, status); } out_sem: up_write((&EXT4_I(inode)->i_data_sem)); if (retval > 0 && map->m_flags & EXT4_MAP_MAPPED) { ret = check_block_validity(inode, map); if (ret != 0) return ret; /* * Inodes with freshly allocated blocks where contents will be * visible after transaction commit must be on transaction's * ordered data list. */ if (map->m_flags & EXT4_MAP_NEW && !(map->m_flags & EXT4_MAP_UNWRITTEN) && !(flags & EXT4_GET_BLOCKS_ZERO) && !ext4_is_quota_file(inode) && ext4_should_order_data(inode)) { loff_t start_byte = (loff_t)map->m_lblk << inode->i_blkbits; loff_t length = (loff_t)map->m_len << inode->i_blkbits; if (flags & EXT4_GET_BLOCKS_IO_SUBMIT) ret = ext4_jbd2_inode_add_wait(handle, inode, start_byte, length); else ret = ext4_jbd2_inode_add_write(handle, inode, start_byte, length); if (ret) return ret; } } if (retval > 0 && (map->m_flags & EXT4_MAP_UNWRITTEN || map->m_flags & EXT4_MAP_MAPPED)) ext4_fc_track_range(handle, inode, map->m_lblk, map->m_lblk + map->m_len - 1); if (retval < 0) ext_debug(inode, "failed with err %d\n", retval); return retval; } /* * Update EXT4_MAP_FLAGS in bh->b_state. For buffer heads attached to pages * we have to be careful as someone else may be manipulating b_state as well. */ static void ext4_update_bh_state(struct buffer_head *bh, unsigned long flags) { unsigned long old_state; unsigned long new_state; flags &= EXT4_MAP_FLAGS; /* Dummy buffer_head? Set non-atomically. */ if (!bh->b_page) { bh->b_state = (bh->b_state & ~EXT4_MAP_FLAGS) | flags; return; } /* * Someone else may be modifying b_state. Be careful! This is ugly but * once we get rid of using bh as a container for mapping information * to pass to / from get_block functions, this can go away. */ old_state = READ_ONCE(bh->b_state); do { new_state = (old_state & ~EXT4_MAP_FLAGS) | flags; } while (unlikely(!try_cmpxchg(&bh->b_state, &old_state, new_state))); } static int _ext4_get_block(struct inode *inode, sector_t iblock, struct buffer_head *bh, int flags) { struct ext4_map_blocks map; int ret = 0; if (ext4_has_inline_data(inode)) return -ERANGE; map.m_lblk = iblock; map.m_len = bh->b_size >> inode->i_blkbits; ret = ext4_map_blocks(ext4_journal_current_handle(), inode, &map, flags); if (ret > 0) { map_bh(bh, inode->i_sb, map.m_pblk); ext4_update_bh_state(bh, map.m_flags); bh->b_size = inode->i_sb->s_blocksize * map.m_len; ret = 0; } else if (ret == 0) { /* hole case, need to fill in bh->b_size */ bh->b_size = inode->i_sb->s_blocksize * map.m_len; } return ret; } int ext4_get_block(struct inode *inode, sector_t iblock, struct buffer_head *bh, int create) { return _ext4_get_block(inode, iblock, bh, create ? EXT4_GET_BLOCKS_CREATE : 0); } /* * Get block function used when preparing for buffered write if we require * creating an unwritten extent if blocks haven't been allocated. The extent * will be converted to written after the IO is complete. */ int ext4_get_block_unwritten(struct inode *inode, sector_t iblock, struct buffer_head *bh_result, int create) { int ret = 0; ext4_debug("ext4_get_block_unwritten: inode %lu, create flag %d\n", inode->i_ino, create); ret = _ext4_get_block(inode, iblock, bh_result, EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT); /* * If the buffer is marked unwritten, mark it as new to make sure it is * zeroed out correctly in case of partial writes. Otherwise, there is * a chance of stale data getting exposed. */ if (ret == 0 && buffer_unwritten(bh_result)) set_buffer_new(bh_result); return ret; } /* Maximum number of blocks we map for direct IO at once. */ #define DIO_MAX_BLOCKS 4096 /* * `handle' can be NULL if create is zero */ struct buffer_head *ext4_getblk(handle_t *handle, struct inode *inode, ext4_lblk_t block, int map_flags) { struct ext4_map_blocks map; struct buffer_head *bh; int create = map_flags & EXT4_GET_BLOCKS_CREATE; bool nowait = map_flags & EXT4_GET_BLOCKS_CACHED_NOWAIT; int err; ASSERT((EXT4_SB(inode->i_sb)->s_mount_state & EXT4_FC_REPLAY) || handle != NULL || create == 0); ASSERT(create == 0 || !nowait); map.m_lblk = block; map.m_len = 1; err = ext4_map_blocks(handle, inode, &map, map_flags); if (err == 0) return create ? ERR_PTR(-ENOSPC) : NULL; if (err < 0) return ERR_PTR(err); if (nowait) return sb_find_get_block(inode->i_sb, map.m_pblk); bh = sb_getblk(inode->i_sb, map.m_pblk); if (unlikely(!bh)) return ERR_PTR(-ENOMEM); if (map.m_flags & EXT4_MAP_NEW) { ASSERT(create != 0); ASSERT((EXT4_SB(inode->i_sb)->s_mount_state & EXT4_FC_REPLAY) || (handle != NULL)); /* * Now that we do not always journal data, we should * keep in mind whether this should always journal the * new buffer as metadata. For now, regular file * writes use ext4_get_block instead, so it's not a * problem. */ lock_buffer(bh); BUFFER_TRACE(bh, "call get_create_access"); err = ext4_journal_get_create_access(handle, inode->i_sb, bh, EXT4_JTR_NONE); if (unlikely(err)) { unlock_buffer(bh); goto errout; } if (!buffer_uptodate(bh)) { memset(bh->b_data, 0, inode->i_sb->s_blocksize); set_buffer_uptodate(bh); } unlock_buffer(bh); BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata"); err = ext4_handle_dirty_metadata(handle, inode, bh); if (unlikely(err)) goto errout; } else BUFFER_TRACE(bh, "not a new buffer"); return bh; errout: brelse(bh); return ERR_PTR(err); } struct buffer_head *ext4_bread(handle_t *handle, struct inode *inode, ext4_lblk_t block, int map_flags) { struct buffer_head *bh; int ret; bh = ext4_getblk(handle, inode, block, map_flags); if (IS_ERR(bh)) return bh; if (!bh || ext4_buffer_uptodate(bh)) return bh; ret = ext4_read_bh_lock(bh, REQ_META | REQ_PRIO, true); if (ret) { put_bh(bh); return ERR_PTR(ret); } return bh; } /* Read a contiguous batch of blocks. */ int ext4_bread_batch(struct inode *inode, ext4_lblk_t block, int bh_count, bool wait, struct buffer_head **bhs) { int i, err; for (i = 0; i < bh_count; i++) { bhs[i] = ext4_getblk(NULL, inode, block + i, 0 /* map_flags */); if (IS_ERR(bhs[i])) { err = PTR_ERR(bhs[i]); bh_count = i; goto out_brelse; } } for (i = 0; i < bh_count; i++) /* Note that NULL bhs[i] is valid because of holes. */ if (bhs[i] && !ext4_buffer_uptodate(bhs[i])) ext4_read_bh_lock(bhs[i], REQ_META | REQ_PRIO, false); if (!wait) return 0; for (i = 0; i < bh_count; i++) if (bhs[i]) wait_on_buffer(bhs[i]); for (i = 0; i < bh_count; i++) { if (bhs[i] && !buffer_uptodate(bhs[i])) { err = -EIO; goto out_brelse; } } return 0; out_brelse: for (i = 0; i < bh_count; i++) { brelse(bhs[i]); bhs[i] = NULL; } return err; } int ext4_walk_page_buffers(handle_t *handle, struct inode *inode, struct buffer_head *head, unsigned from, unsigned to, int *partial, int (*fn)(handle_t *handle, struct inode *inode, struct buffer_head *bh)) { struct buffer_head *bh; unsigned block_start, block_end; unsigned blocksize = head->b_size; int err, ret = 0; struct buffer_head *next; for (bh = head, block_start = 0; ret == 0 && (bh != head || !block_start); block_start = block_end, bh = next) { next = bh->b_this_page; block_end = block_start + blocksize; if (block_end <= from || block_start >= to) { if (partial && !buffer_uptodate(bh)) *partial = 1; continue; } err = (*fn)(handle, inode, bh); if (!ret) ret = err; } return ret; } /* * Helper for handling dirtying of journalled data. We also mark the folio as * dirty so that writeback code knows about this page (and inode) contains * dirty data. ext4_writepages() then commits appropriate transaction to * make data stable. */ static int ext4_dirty_journalled_data(handle_t *handle, struct buffer_head *bh) { folio_mark_dirty(bh->b_folio); return ext4_handle_dirty_metadata(handle, NULL, bh); } int do_journal_get_write_access(handle_t *handle, struct inode *inode, struct buffer_head *bh) { int dirty = buffer_dirty(bh); int ret; if (!buffer_mapped(bh) || buffer_freed(bh)) return 0; /* * __block_write_begin() could have dirtied some buffers. Clean * the dirty bit as jbd2_journal_get_write_access() could complain * otherwise about fs integrity issues. Setting of the dirty bit * by __block_write_begin() isn't a real problem here as we clear * the bit before releasing a page lock and thus writeback cannot * ever write the buffer. */ if (dirty) clear_buffer_dirty(bh); BUFFER_TRACE(bh, "get write access"); ret = ext4_journal_get_write_access(handle, inode->i_sb, bh, EXT4_JTR_NONE); if (!ret && dirty) ret = ext4_dirty_journalled_data(handle, bh); return ret; } #ifdef CONFIG_FS_ENCRYPTION static int ext4_block_write_begin(struct folio *folio, loff_t pos, unsigned len, get_block_t *get_block) { unsigned from = pos & (PAGE_SIZE - 1); unsigned to = from + len; struct inode *inode = folio->mapping->host; unsigned block_start, block_end; sector_t block; int err = 0; unsigned blocksize = inode->i_sb->s_blocksize; unsigned bbits; struct buffer_head *bh, *head, *wait[2]; int nr_wait = 0; int i; BUG_ON(!folio_test_locked(folio)); BUG_ON(from > PAGE_SIZE); BUG_ON(to > PAGE_SIZE); BUG_ON(from > to); head = folio_buffers(folio); if (!head) head = create_empty_buffers(folio, blocksize, 0); bbits = ilog2(blocksize); block = (sector_t)folio->index << (PAGE_SHIFT - bbits); for (bh = head, block_start = 0; bh != head || !block_start; block++, block_start = block_end, bh = bh->b_this_page) { block_end = block_start + blocksize; if (block_end <= from || block_start >= to) { if (folio_test_uptodate(folio)) { set_buffer_uptodate(bh); } continue; } if (buffer_new(bh)) clear_buffer_new(bh); if (!buffer_mapped(bh)) { WARN_ON(bh->b_size != blocksize); err = get_block(inode, block, bh, 1); if (err) break; if (buffer_new(bh)) { if (folio_test_uptodate(folio)) { clear_buffer_new(bh); set_buffer_uptodate(bh); mark_buffer_dirty(bh); continue; } if (block_end > to || block_start < from) folio_zero_segments(folio, to, block_end, block_start, from); continue; } } if (folio_test_uptodate(folio)) { set_buffer_uptodate(bh); continue; } if (!buffer_uptodate(bh) && !buffer_delay(bh) && !buffer_unwritten(bh) && (block_start < from || block_end > to)) { ext4_read_bh_lock(bh, 0, false); wait[nr_wait++] = bh; } } /* * If we issued read requests, let them complete. */ for (i = 0; i < nr_wait; i++) { wait_on_buffer(wait[i]); if (!buffer_uptodate(wait[i])) err = -EIO; } if (unlikely(err)) { folio_zero_new_buffers(folio, from, to); } else if (fscrypt_inode_uses_fs_layer_crypto(inode)) { for (i = 0; i < nr_wait; i++) { int err2; err2 = fscrypt_decrypt_pagecache_blocks(folio, blocksize, bh_offset(wait[i])); if (err2) { clear_buffer_uptodate(wait[i]); err = err2; } } } return err; } #endif /* * To preserve ordering, it is essential that the hole instantiation and * the data write be encapsulated in a single transaction. We cannot * close off a transaction and start a new one between the ext4_get_block() * and the ext4_write_end(). So doing the jbd2_journal_start at the start of * ext4_write_begin() is the right place. */ static int ext4_write_begin(struct file *file, struct address_space *mapping, loff_t pos, unsigned len, struct page **pagep, void **fsdata) { struct inode *inode = mapping->host; int ret, needed_blocks; handle_t *handle; int retries = 0; struct folio *folio; pgoff_t index; unsigned from, to; if (unlikely(ext4_forced_shutdown(inode->i_sb))) return -EIO; trace_ext4_write_begin(inode, pos, len); /* * Reserve one block more for addition to orphan list in case * we allocate blocks but write fails for some reason */ needed_blocks = ext4_writepage_trans_blocks(inode) + 1; index = pos >> PAGE_SHIFT; from = pos & (PAGE_SIZE - 1); to = from + len; if (ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA)) { ret = ext4_try_to_write_inline_data(mapping, inode, pos, len, pagep); if (ret < 0) return ret; if (ret == 1) return 0; } /* * __filemap_get_folio() can take a long time if the * system is thrashing due to memory pressure, or if the folio * is being written back. So grab it first before we start * the transaction handle. This also allows us to allocate * the folio (if needed) without using GFP_NOFS. */ retry_grab: folio = __filemap_get_folio(mapping, index, FGP_WRITEBEGIN, mapping_gfp_mask(mapping)); if (IS_ERR(folio)) return PTR_ERR(folio); /* * The same as page allocation, we prealloc buffer heads before * starting the handle. */ if (!folio_buffers(folio)) create_empty_buffers(folio, inode->i_sb->s_blocksize, 0); folio_unlock(folio); retry_journal: handle = ext4_journal_start(inode, EXT4_HT_WRITE_PAGE, needed_blocks); if (IS_ERR(handle)) { folio_put(folio); return PTR_ERR(handle); } folio_lock(folio); if (folio->mapping != mapping) { /* The folio got truncated from under us */ folio_unlock(folio); folio_put(folio); ext4_journal_stop(handle); goto retry_grab; } /* In case writeback began while the folio was unlocked */ folio_wait_stable(folio); #ifdef CONFIG_FS_ENCRYPTION if (ext4_should_dioread_nolock(inode)) ret = ext4_block_write_begin(folio, pos, len, ext4_get_block_unwritten); else ret = ext4_block_write_begin(folio, pos, len, ext4_get_block); #else if (ext4_should_dioread_nolock(inode)) ret = __block_write_begin(&folio->page, pos, len, ext4_get_block_unwritten); else ret = __block_write_begin(&folio->page, pos, len, ext4_get_block); #endif if (!ret && ext4_should_journal_data(inode)) { ret = ext4_walk_page_buffers(handle, inode, folio_buffers(folio), from, to, NULL, do_journal_get_write_access); } if (ret) { bool extended = (pos + len > inode->i_size) && !ext4_verity_in_progress(inode); folio_unlock(folio); /* * __block_write_begin may have instantiated a few blocks * outside i_size. Trim these off again. Don't need * i_size_read because we hold i_rwsem. * * Add inode to orphan list in case we crash before * truncate finishes */ if (extended && ext4_can_truncate(inode)) ext4_orphan_add(handle, inode); ext4_journal_stop(handle); if (extended) { ext4_truncate_failed_write(inode); /* * If truncate failed early the inode might * still be on the orphan list; we need to * make sure the inode is removed from the * orphan list in that case. */ if (inode->i_nlink) ext4_orphan_del(NULL, inode); } if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries)) goto retry_journal; folio_put(folio); return ret; } *pagep = &folio->page; return ret; } /* For write_end() in data=journal mode */ static int write_end_fn(handle_t *handle, struct inode *inode, struct buffer_head *bh) { int ret; if (!buffer_mapped(bh) || buffer_freed(bh)) return 0; set_buffer_uptodate(bh); ret = ext4_dirty_journalled_data(handle, bh); clear_buffer_meta(bh); clear_buffer_prio(bh); return ret; } /* * We need to pick up the new inode size which generic_commit_write gave us * `file' can be NULL - eg, when called from page_symlink(). * * ext4 never places buffers on inode->i_mapping->i_private_list. metadata * buffers are managed internally. */ static int ext4_write_end(struct file *file, struct address_space *mapping, loff_t pos, unsigned len, unsigned copied, struct page *page, void *fsdata) { struct folio *folio = page_folio(page); handle_t *handle = ext4_journal_current_handle(); struct inode *inode = mapping->host; loff_t old_size = inode->i_size; int ret = 0, ret2; int i_size_changed = 0; bool verity = ext4_verity_in_progress(inode); trace_ext4_write_end(inode, pos, len, copied); if (ext4_has_inline_data(inode) && ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA)) return ext4_write_inline_data_end(inode, pos, len, copied, folio); copied = block_write_end(file, mapping, pos, len, copied, page, fsdata); /* * it's important to update i_size while still holding folio lock: * page writeout could otherwise come in and zero beyond i_size. * * If FS_IOC_ENABLE_VERITY is running on this inode, then Merkle tree * blocks are being written past EOF, so skip the i_size update. */ if (!verity) i_size_changed = ext4_update_inode_size(inode, pos + copied); folio_unlock(folio); folio_put(folio); if (old_size < pos && !verity) pagecache_isize_extended(inode, old_size, pos); /* * Don't mark the inode dirty under folio lock. First, it unnecessarily * makes the holding time of folio lock longer. Second, it forces lock * ordering of folio lock and transaction start for journaling * filesystems. */ if (i_size_changed) ret = ext4_mark_inode_dirty(handle, inode); if (pos + len > inode->i_size && !verity && ext4_can_truncate(inode)) /* if we have allocated more blocks and copied * less. We will have blocks allocated outside * inode->i_size. So truncate them */ ext4_orphan_add(handle, inode); ret2 = ext4_journal_stop(handle); if (!ret) ret = ret2; if (pos + len > inode->i_size && !verity) { ext4_truncate_failed_write(inode); /* * If truncate failed early the inode might still be * on the orphan list; we need to make sure the inode * is removed from the orphan list in that case. */ if (inode->i_nlink) ext4_orphan_del(NULL, inode); } return ret ? ret : copied; } /* * This is a private version of folio_zero_new_buffers() which doesn't * set the buffer to be dirty, since in data=journalled mode we need * to call ext4_dirty_journalled_data() instead. */ static void ext4_journalled_zero_new_buffers(handle_t *handle, struct inode *inode, struct folio *folio, unsigned from, unsigned to) { unsigned int block_start = 0, block_end; struct buffer_head *head, *bh; bh = head = folio_buffers(folio); do { block_end = block_start + bh->b_size; if (buffer_new(bh)) { if (block_end > from && block_start < to) { if (!folio_test_uptodate(folio)) { unsigned start, size; start = max(from, block_start); size = min(to, block_end) - start; folio_zero_range(folio, start, size); write_end_fn(handle, inode, bh); } clear_buffer_new(bh); } } block_start = block_end; bh = bh->b_this_page; } while (bh != head); } static int ext4_journalled_write_end(struct file *file, struct address_space *mapping, loff_t pos, unsigned len, unsigned copied, struct page *page, void *fsdata) { struct folio *folio = page_folio(page); handle_t *handle = ext4_journal_current_handle(); struct inode *inode = mapping->host; loff_t old_size = inode->i_size; int ret = 0, ret2; int partial = 0; unsigned from, to; int size_changed = 0; bool verity = ext4_verity_in_progress(inode); trace_ext4_journalled_write_end(inode, pos, len, copied); from = pos & (PAGE_SIZE - 1); to = from + len; BUG_ON(!ext4_handle_valid(handle)); if (ext4_has_inline_data(inode)) return ext4_write_inline_data_end(inode, pos, len, copied, folio); if (unlikely(copied < len) && !folio_test_uptodate(folio)) { copied = 0; ext4_journalled_zero_new_buffers(handle, inode, folio, from, to); } else { if (unlikely(copied < len)) ext4_journalled_zero_new_buffers(handle, inode, folio, from + copied, to); ret = ext4_walk_page_buffers(handle, inode, folio_buffers(folio), from, from + copied, &partial, write_end_fn); if (!partial) folio_mark_uptodate(folio); } if (!verity) size_changed = ext4_update_inode_size(inode, pos + copied); EXT4_I(inode)->i_datasync_tid = handle->h_transaction->t_tid; folio_unlock(folio); folio_put(folio); if (old_size < pos && !verity) pagecache_isize_extended(inode, old_size, pos); if (size_changed) { ret2 = ext4_mark_inode_dirty(handle, inode); if (!ret) ret = ret2; } if (pos + len > inode->i_size && !verity && ext4_can_truncate(inode)) /* if we have allocated more blocks and copied * less. We will have blocks allocated outside * inode->i_size. So truncate them */ ext4_orphan_add(handle, inode); ret2 = ext4_journal_stop(handle); if (!ret) ret = ret2; if (pos + len > inode->i_size && !verity) { ext4_truncate_failed_write(inode); /* * If truncate failed early the inode might still be * on the orphan list; we need to make sure the inode * is removed from the orphan list in that case. */ if (inode->i_nlink) ext4_orphan_del(NULL, inode); } return ret ? ret : copied; } /* * Reserve space for 'nr_resv' clusters */ static int ext4_da_reserve_space(struct inode *inode, int nr_resv) { struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); struct ext4_inode_info *ei = EXT4_I(inode); int ret; /* * We will charge metadata quota at writeout time; this saves * us from metadata over-estimation, though we may go over by * a small amount in the end. Here we just reserve for data. */ ret = dquot_reserve_block(inode, EXT4_C2B(sbi, nr_resv)); if (ret) return ret; spin_lock(&ei->i_block_reservation_lock); if (ext4_claim_free_clusters(sbi, nr_resv, 0)) { spin_unlock(&ei->i_block_reservation_lock); dquot_release_reservation_block(inode, EXT4_C2B(sbi, nr_resv)); return -ENOSPC; } ei->i_reserved_data_blocks += nr_resv; trace_ext4_da_reserve_space(inode, nr_resv); spin_unlock(&ei->i_block_reservation_lock); return 0; /* success */ } void ext4_da_release_space(struct inode *inode, int to_free) { struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); struct ext4_inode_info *ei = EXT4_I(inode); if (!to_free) return; /* Nothing to release, exit */ spin_lock(&EXT4_I(inode)->i_block_reservation_lock); trace_ext4_da_release_space(inode, to_free); if (unlikely(to_free > ei->i_reserved_data_blocks)) { /* * if there aren't enough reserved blocks, then the * counter is messed up somewhere. Since this * function is called from invalidate page, it's * harmless to return without any action. */ ext4_warning(inode->i_sb, "ext4_da_release_space: " "ino %lu, to_free %d with only %d reserved " "data blocks", inode->i_ino, to_free, ei->i_reserved_data_blocks); WARN_ON(1); to_free = ei->i_reserved_data_blocks; } ei->i_reserved_data_blocks -= to_free; /* update fs dirty data blocks counter */ percpu_counter_sub(&sbi->s_dirtyclusters_counter, to_free); spin_unlock(&EXT4_I(inode)->i_block_reservation_lock); dquot_release_reservation_block(inode, EXT4_C2B(sbi, to_free)); } /* * Delayed allocation stuff */ struct mpage_da_data { /* These are input fields for ext4_do_writepages() */ struct inode *inode; struct writeback_control *wbc; unsigned int can_map:1; /* Can writepages call map blocks? */ /* These are internal state of ext4_do_writepages() */ pgoff_t first_page; /* The first page to write */ pgoff_t next_page; /* Current page to examine */ pgoff_t last_page; /* Last page to examine */ /* * Extent to map - this can be after first_page because that can be * fully mapped. We somewhat abuse m_flags to store whether the extent * is delalloc or unwritten. */ struct ext4_map_blocks map; struct ext4_io_submit io_submit; /* IO submission data */ unsigned int do_map:1; unsigned int scanned_until_end:1; unsigned int journalled_more_data:1; }; static void mpage_release_unused_pages(struct mpage_da_data *mpd, bool invalidate) { unsigned nr, i; pgoff_t index, end; struct folio_batch fbatch; struct inode *inode = mpd->inode; struct address_space *mapping = inode->i_mapping; /* This is necessary when next_page == 0. */ if (mpd->first_page >= mpd->next_page) return; mpd->scanned_until_end = 0; index = mpd->first_page; end = mpd->next_page - 1; if (invalidate) { ext4_lblk_t start, last; start = index << (PAGE_SHIFT - inode->i_blkbits); last = end << (PAGE_SHIFT - inode->i_blkbits); /* * avoid racing with extent status tree scans made by * ext4_insert_delayed_block() */ down_write(&EXT4_I(inode)->i_data_sem); ext4_es_remove_extent(inode, start, last - start + 1); up_write(&EXT4_I(inode)->i_data_sem); } folio_batch_init(&fbatch); while (index <= end) { nr = filemap_get_folios(mapping, &index, end, &fbatch); if (nr == 0) break; for (i = 0; i < nr; i++) { struct folio *folio = fbatch.folios[i]; if (folio->index < mpd->first_page) continue; if (folio_next_index(folio) - 1 > end) continue; BUG_ON(!folio_test_locked(folio)); BUG_ON(folio_test_writeback(folio)); if (invalidate) { if (folio_mapped(folio)) folio_clear_dirty_for_io(folio); block_invalidate_folio(folio, 0, folio_size(folio)); folio_clear_uptodate(folio); } folio_unlock(folio); } folio_batch_release(&fbatch); } } static void ext4_print_free_blocks(struct inode *inode) { struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); struct super_block *sb = inode->i_sb; struct ext4_inode_info *ei = EXT4_I(inode); ext4_msg(sb, KERN_CRIT, "Total free blocks count %lld", EXT4_C2B(EXT4_SB(inode->i_sb), ext4_count_free_clusters(sb))); ext4_msg(sb, KERN_CRIT, "Free/Dirty block details"); ext4_msg(sb, KERN_CRIT, "free_blocks=%lld", (long long) EXT4_C2B(EXT4_SB(sb), percpu_counter_sum(&sbi->s_freeclusters_counter))); ext4_msg(sb, KERN_CRIT, "dirty_blocks=%lld", (long long) EXT4_C2B(EXT4_SB(sb), percpu_counter_sum(&sbi->s_dirtyclusters_counter))); ext4_msg(sb, KERN_CRIT, "Block reservation details"); ext4_msg(sb, KERN_CRIT, "i_reserved_data_blocks=%u", ei->i_reserved_data_blocks); return; } /* * Check whether the cluster containing lblk has been allocated or has * delalloc reservation. * * Returns 0 if the cluster doesn't have either, 1 if it has delalloc * reservation, 2 if it's already been allocated, negative error code on * failure. */ static int ext4_clu_alloc_state(struct inode *inode, ext4_lblk_t lblk) { struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); int ret; /* Has delalloc reservation? */ if (ext4_es_scan_clu(inode, &ext4_es_is_delonly, lblk)) return 1; /* Already been allocated? */ if (ext4_es_scan_clu(inode, &ext4_es_is_mapped, lblk)) return 2; ret = ext4_clu_mapped(inode, EXT4_B2C(sbi, lblk)); if (ret < 0) return ret; if (ret > 0) return 2; return 0; } /* * ext4_insert_delayed_blocks - adds a multiple delayed blocks to the extents * status tree, incrementing the reserved * cluster/block count or making pending * reservations where needed * * @inode - file containing the newly added block * @lblk - start logical block to be added * @len - length of blocks to be added * * Returns 0 on success, negative error code on failure. */ static int ext4_insert_delayed_blocks(struct inode *inode, ext4_lblk_t lblk, ext4_lblk_t len) { struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); int ret; bool lclu_allocated = false; bool end_allocated = false; ext4_lblk_t resv_clu; ext4_lblk_t end = lblk + len - 1; /* * If the cluster containing lblk or end is shared with a delayed, * written, or unwritten extent in a bigalloc file system, it's * already been accounted for and does not need to be reserved. * A pending reservation must be made for the cluster if it's * shared with a written or unwritten extent and doesn't already * have one. Written and unwritten extents can be purged from the * extents status tree if the system is under memory pressure, so * it's necessary to examine the extent tree if a search of the * extents status tree doesn't get a match. */ if (sbi->s_cluster_ratio == 1) { ret = ext4_da_reserve_space(inode, len); if (ret != 0) /* ENOSPC */ return ret; } else { /* bigalloc */ resv_clu = EXT4_B2C(sbi, end) - EXT4_B2C(sbi, lblk) + 1; ret = ext4_clu_alloc_state(inode, lblk); if (ret < 0) return ret; if (ret > 0) { resv_clu--; lclu_allocated = (ret == 2); } if (EXT4_B2C(sbi, lblk) != EXT4_B2C(sbi, end)) { ret = ext4_clu_alloc_state(inode, end); if (ret < 0) return ret; if (ret > 0) { resv_clu--; end_allocated = (ret == 2); } } if (resv_clu) { ret = ext4_da_reserve_space(inode, resv_clu); if (ret != 0) /* ENOSPC */ return ret; } } ext4_es_insert_delayed_extent(inode, lblk, len, lclu_allocated, end_allocated); return 0; } /* * Looks up the requested blocks and sets the delalloc extent map. * First try to look up for the extent entry that contains the requested * blocks in the extent status tree without i_data_sem, then try to look * up for the ondisk extent mapping with i_data_sem in read mode, * finally hold i_data_sem in write mode, looks up again and add a * delalloc extent entry if it still couldn't find any extent. Pass out * the mapped extent through @map and return 0 on success. */ static int ext4_da_map_blocks(struct inode *inode, struct ext4_map_blocks *map) { struct extent_status es; int retval; #ifdef ES_AGGRESSIVE_TEST struct ext4_map_blocks orig_map; memcpy(&orig_map, map, sizeof(*map)); #endif map->m_flags = 0; ext_debug(inode, "max_blocks %u, logical block %lu\n", map->m_len, (unsigned long) map->m_lblk); /* Lookup extent status tree firstly */ if (ext4_es_lookup_extent(inode, map->m_lblk, NULL, &es)) { map->m_len = min_t(unsigned int, map->m_len, es.es_len - (map->m_lblk - es.es_lblk)); if (ext4_es_is_hole(&es)) goto add_delayed; found: /* * Delayed extent could be allocated by fallocate. * So we need to check it. */ if (ext4_es_is_delonly(&es)) { map->m_flags |= EXT4_MAP_DELAYED; return 0; } map->m_pblk = ext4_es_pblock(&es) + map->m_lblk - es.es_lblk; if (ext4_es_is_written(&es)) map->m_flags |= EXT4_MAP_MAPPED; else if (ext4_es_is_unwritten(&es)) map->m_flags |= EXT4_MAP_UNWRITTEN; else BUG(); #ifdef ES_AGGRESSIVE_TEST ext4_map_blocks_es_recheck(NULL, inode, map, &orig_map, 0); #endif return 0; } /* * Try to see if we can get the block without requesting a new * file system block. */ down_read(&EXT4_I(inode)->i_data_sem); if (ext4_has_inline_data(inode)) retval = 0; else retval = ext4_map_query_blocks(NULL, inode, map); up_read(&EXT4_I(inode)->i_data_sem); if (retval) return retval < 0 ? retval : 0; add_delayed: down_write(&EXT4_I(inode)->i_data_sem); /* * Page fault path (ext4_page_mkwrite does not take i_rwsem) * and fallocate path (no folio lock) can race. Make sure we * lookup the extent status tree here again while i_data_sem * is held in write mode, before inserting a new da entry in * the extent status tree. */ if (ext4_es_lookup_extent(inode, map->m_lblk, NULL, &es)) { map->m_len = min_t(unsigned int, map->m_len, es.es_len - (map->m_lblk - es.es_lblk)); if (!ext4_es_is_hole(&es)) { up_write(&EXT4_I(inode)->i_data_sem); goto found; } } else if (!ext4_has_inline_data(inode)) { retval = ext4_map_query_blocks(NULL, inode, map); if (retval) { up_write(&EXT4_I(inode)->i_data_sem); return retval < 0 ? retval : 0; } } map->m_flags |= EXT4_MAP_DELAYED; retval = ext4_insert_delayed_blocks(inode, map->m_lblk, map->m_len); up_write(&EXT4_I(inode)->i_data_sem); return retval; } /* * This is a special get_block_t callback which is used by * ext4_da_write_begin(). It will either return mapped block or * reserve space for a single block. * * For delayed buffer_head we have BH_Mapped, BH_New, BH_Delay set. * We also have b_blocknr = -1 and b_bdev initialized properly * * For unwritten buffer_head we have BH_Mapped, BH_New, BH_Unwritten set. * We also have b_blocknr = physicalblock mapping unwritten extent and b_bdev * initialized properly. */ int ext4_da_get_block_prep(struct inode *inode, sector_t iblock, struct buffer_head *bh, int create) { struct ext4_map_blocks map; sector_t invalid_block = ~((sector_t) 0xffff); int ret = 0; BUG_ON(create == 0); BUG_ON(bh->b_size != inode->i_sb->s_blocksize); if (invalid_block < ext4_blocks_count(EXT4_SB(inode->i_sb)->s_es)) invalid_block = ~0; map.m_lblk = iblock; map.m_len = 1; /* * first, we need to know whether the block is allocated already * preallocated blocks are unmapped but should treated * the same as allocated blocks. */ ret = ext4_da_map_blocks(inode, &map); if (ret < 0) return ret; if (map.m_flags & EXT4_MAP_DELAYED) { map_bh(bh, inode->i_sb, invalid_block); set_buffer_new(bh); set_buffer_delay(bh); return 0; } map_bh(bh, inode->i_sb, map.m_pblk); ext4_update_bh_state(bh, map.m_flags); if (buffer_unwritten(bh)) { /* A delayed write to unwritten bh should be marked * new and mapped. Mapped ensures that we don't do * get_block multiple times when we write to the same * offset and new ensures that we do proper zero out * for partial write. */ set_buffer_new(bh); set_buffer_mapped(bh); } return 0; } static void mpage_folio_done(struct mpage_da_data *mpd, struct folio *folio) { mpd->first_page += folio_nr_pages(folio); folio_unlock(folio); } static int mpage_submit_folio(struct mpage_da_data *mpd, struct folio *folio) { size_t len; loff_t size; int err; BUG_ON(folio->index != mpd->first_page); folio_clear_dirty_for_io(folio); /* * We have to be very careful here! Nothing protects writeback path * against i_size changes and the page can be writeably mapped into * page tables. So an application can be growing i_size and writing * data through mmap while writeback runs. folio_clear_dirty_for_io() * write-protects our page in page tables and the page cannot get * written to again until we release folio lock. So only after * folio_clear_dirty_for_io() we are safe to sample i_size for * ext4_bio_write_folio() to zero-out tail of the written page. We rely * on the barrier provided by folio_test_clear_dirty() in * folio_clear_dirty_for_io() to make sure i_size is really sampled only * after page tables are updated. */ size = i_size_read(mpd->inode); len = folio_size(folio); if (folio_pos(folio) + len > size && !ext4_verity_in_progress(mpd->inode)) len = size & (len - 1); err = ext4_bio_write_folio(&mpd->io_submit, folio, len); if (!err) mpd->wbc->nr_to_write--; return err; } #define BH_FLAGS (BIT(BH_Unwritten) | BIT(BH_Delay)) /* * mballoc gives us at most this number of blocks... * XXX: That seems to be only a limitation of ext4_mb_normalize_request(). * The rest of mballoc seems to handle chunks up to full group size. */ #define MAX_WRITEPAGES_EXTENT_LEN 2048 /* * mpage_add_bh_to_extent - try to add bh to extent of blocks to map * * @mpd - extent of blocks * @lblk - logical number of the block in the file * @bh - buffer head we want to add to the extent * * The function is used to collect contig. blocks in the same state. If the * buffer doesn't require mapping for writeback and we haven't started the * extent of buffers to map yet, the function returns 'true' immediately - the * caller can write the buffer right away. Otherwise the function returns true * if the block has been added to the extent, false if the block couldn't be * added. */ static bool mpage_add_bh_to_extent(struct mpage_da_data *mpd, ext4_lblk_t lblk, struct buffer_head *bh) { struct ext4_map_blocks *map = &mpd->map; /* Buffer that doesn't need mapping for writeback? */ if (!buffer_dirty(bh) || !buffer_mapped(bh) || (!buffer_delay(bh) && !buffer_unwritten(bh))) { /* So far no extent to map => we write the buffer right away */ if (map->m_len == 0) return true; return false; } /* First block in the extent? */ if (map->m_len == 0) { /* We cannot map unless handle is started... */ if (!mpd->do_map) return false; map->m_lblk = lblk; map->m_len = 1; map->m_flags = bh->b_state & BH_FLAGS; return true; } /* Don't go larger than mballoc is willing to allocate */ if (map->m_len >= MAX_WRITEPAGES_EXTENT_LEN) return false; /* Can we merge the block to our big extent? */ if (lblk == map->m_lblk + map->m_len && (bh->b_state & BH_FLAGS) == map->m_flags) { map->m_len++; return true; } return false; } /* * mpage_process_page_bufs - submit page buffers for IO or add them to extent * * @mpd - extent of blocks for mapping * @head - the first buffer in the page * @bh - buffer we should start processing from * @lblk - logical number of the block in the file corresponding to @bh * * Walk through page buffers from @bh upto @head (exclusive) and either submit * the page for IO if all buffers in this page were mapped and there's no * accumulated extent of buffers to map or add buffers in the page to the * extent of buffers to map. The function returns 1 if the caller can continue * by processing the next page, 0 if it should stop adding buffers to the * extent to map because we cannot extend it anymore. It can also return value * < 0 in case of error during IO submission. */ static int mpage_process_page_bufs(struct mpage_da_data *mpd, struct buffer_head *head, struct buffer_head *bh, ext4_lblk_t lblk) { struct inode *inode = mpd->inode; int err; ext4_lblk_t blocks = (i_size_read(inode) + i_blocksize(inode) - 1) >> inode->i_blkbits; if (ext4_verity_in_progress(inode)) blocks = EXT_MAX_BLOCKS; do { BUG_ON(buffer_locked(bh)); if (lblk >= blocks || !mpage_add_bh_to_extent(mpd, lblk, bh)) { /* Found extent to map? */ if (mpd->map.m_len) return 0; /* Buffer needs mapping and handle is not started? */ if (!mpd->do_map) return 0; /* Everything mapped so far and we hit EOF */ break; } } while (lblk++, (bh = bh->b_this_page) != head); /* So far everything mapped? Submit the page for IO. */ if (mpd->map.m_len == 0) { err = mpage_submit_folio(mpd, head->b_folio); if (err < 0) return err; mpage_folio_done(mpd, head->b_folio); } if (lblk >= blocks) { mpd->scanned_until_end = 1; return 0; } return 1; } /* * mpage_process_folio - update folio buffers corresponding to changed extent * and may submit fully mapped page for IO * @mpd: description of extent to map, on return next extent to map * @folio: Contains these buffers. * @m_lblk: logical block mapping. * @m_pblk: corresponding physical mapping. * @map_bh: determines on return whether this page requires any further * mapping or not. * * Scan given folio buffers corresponding to changed extent and update buffer * state according to new extent state. * We map delalloc buffers to their physical location, clear unwritten bits. * If the given folio is not fully mapped, we update @mpd to the next extent in * the given folio that needs mapping & return @map_bh as true. */ static int mpage_process_folio(struct mpage_da_data *mpd, struct folio *folio, ext4_lblk_t *m_lblk, ext4_fsblk_t *m_pblk, bool *map_bh) { struct buffer_head *head, *bh; ext4_io_end_t *io_end = mpd->io_submit.io_end; ext4_lblk_t lblk = *m_lblk; ext4_fsblk_t pblock = *m_pblk; int err = 0; int blkbits = mpd->inode->i_blkbits; ssize_t io_end_size = 0; struct ext4_io_end_vec *io_end_vec = ext4_last_io_end_vec(io_end); bh = head = folio_buffers(folio); do { if (lblk < mpd->map.m_lblk) continue; if (lblk >= mpd->map.m_lblk + mpd->map.m_len) { /* * Buffer after end of mapped extent. * Find next buffer in the folio to map. */ mpd->map.m_len = 0; mpd->map.m_flags = 0; io_end_vec->size += io_end_size; err = mpage_process_page_bufs(mpd, head, bh, lblk); if (err > 0) err = 0; if (!err && mpd->map.m_len && mpd->map.m_lblk > lblk) { io_end_vec = ext4_alloc_io_end_vec(io_end); if (IS_ERR(io_end_vec)) { err = PTR_ERR(io_end_vec); goto out; } io_end_vec->offset = (loff_t)mpd->map.m_lblk << blkbits; } *map_bh = true; goto out; } if (buffer_delay(bh)) { clear_buffer_delay(bh); bh->b_blocknr = pblock++; } clear_buffer_unwritten(bh); io_end_size += (1 << blkbits); } while (lblk++, (bh = bh->b_this_page) != head); io_end_vec->size += io_end_size; *map_bh = false; out: *m_lblk = lblk; *m_pblk = pblock; return err; } /* * mpage_map_buffers - update buffers corresponding to changed extent and * submit fully mapped pages for IO * * @mpd - description of extent to map, on return next extent to map * * Scan buffers corresponding to changed extent (we expect corresponding pages * to be already locked) and update buffer state according to new extent state. * We map delalloc buffers to their physical location, clear unwritten bits, * and mark buffers as uninit when we perform writes to unwritten extents * and do extent conversion after IO is finished. If the last page is not fully * mapped, we update @map to the next extent in the last page that needs * mapping. Otherwise we submit the page for IO. */ static int mpage_map_and_submit_buffers(struct mpage_da_data *mpd) { struct folio_batch fbatch; unsigned nr, i; struct inode *inode = mpd->inode; int bpp_bits = PAGE_SHIFT - inode->i_blkbits; pgoff_t start, end; ext4_lblk_t lblk; ext4_fsblk_t pblock; int err; bool map_bh = false; start = mpd->map.m_lblk >> bpp_bits; end = (mpd->map.m_lblk + mpd->map.m_len - 1) >> bpp_bits; lblk = start << bpp_bits; pblock = mpd->map.m_pblk; folio_batch_init(&fbatch); while (start <= end) { nr = filemap_get_folios(inode->i_mapping, &start, end, &fbatch); if (nr == 0) break; for (i = 0; i < nr; i++) { struct folio *folio = fbatch.folios[i]; err = mpage_process_folio(mpd, folio, &lblk, &pblock, &map_bh); /* * If map_bh is true, means page may require further bh * mapping, or maybe the page was submitted for IO. * So we return to call further extent mapping. */ if (err < 0 || map_bh) goto out; /* Page fully mapped - let IO run! */ err = mpage_submit_folio(mpd, folio); if (err < 0) goto out; mpage_folio_done(mpd, folio); } folio_batch_release(&fbatch); } /* Extent fully mapped and matches with page boundary. We are done. */ mpd->map.m_len = 0; mpd->map.m_flags = 0; return 0; out: folio_batch_release(&fbatch); return err; } static int mpage_map_one_extent(handle_t *handle, struct mpage_da_data *mpd) { struct inode *inode = mpd->inode; struct ext4_map_blocks *map = &mpd->map; int get_blocks_flags; int err, dioread_nolock; trace_ext4_da_write_pages_extent(inode, map); /* * Call ext4_map_blocks() to allocate any delayed allocation blocks, or * to convert an unwritten extent to be initialized (in the case * where we have written into one or more preallocated blocks). It is * possible that we're going to need more metadata blocks than * previously reserved. However we must not fail because we're in * writeback and there is nothing we can do about it so it might result * in data loss. So use reserved blocks to allocate metadata if * possible. * * We pass in the magic EXT4_GET_BLOCKS_DELALLOC_RESERVE if * the blocks in question are delalloc blocks. This indicates * that the blocks and quotas has already been checked when * the data was copied into the page cache. */ get_blocks_flags = EXT4_GET_BLOCKS_CREATE | EXT4_GET_BLOCKS_METADATA_NOFAIL | EXT4_GET_BLOCKS_IO_SUBMIT; dioread_nolock = ext4_should_dioread_nolock(inode); if (dioread_nolock) get_blocks_flags |= EXT4_GET_BLOCKS_IO_CREATE_EXT; if (map->m_flags & BIT(BH_Delay)) get_blocks_flags |= EXT4_GET_BLOCKS_DELALLOC_RESERVE; err = ext4_map_blocks(handle, inode, map, get_blocks_flags); if (err < 0) return err; if (dioread_nolock && (map->m_flags & EXT4_MAP_UNWRITTEN)) { if (!mpd->io_submit.io_end->handle && ext4_handle_valid(handle)) { mpd->io_submit.io_end->handle = handle->h_rsv_handle; handle->h_rsv_handle = NULL; } ext4_set_io_unwritten_flag(inode, mpd->io_submit.io_end); } BUG_ON(map->m_len == 0); return 0; } /* * mpage_map_and_submit_extent - map extent starting at mpd->lblk of length * mpd->len and submit pages underlying it for IO * * @handle - handle for journal operations * @mpd - extent to map * @give_up_on_write - we set this to true iff there is a fatal error and there * is no hope of writing the data. The caller should discard * dirty pages to avoid infinite loops. * * The function maps extent starting at mpd->lblk of length mpd->len. If it is * delayed, blocks are allocated, if it is unwritten, we may need to convert * them to initialized or split the described range from larger unwritten * extent. Note that we need not map all the described range since allocation * can return less blocks or the range is covered by more unwritten extents. We * cannot map more because we are limited by reserved transaction credits. On * the other hand we always make sure that the last touched page is fully * mapped so that it can be written out (and thus forward progress is * guaranteed). After mapping we submit all mapped pages for IO. */ static int mpage_map_and_submit_extent(handle_t *handle, struct mpage_da_data *mpd, bool *give_up_on_write) { struct inode *inode = mpd->inode; struct ext4_map_blocks *map = &mpd->map; int err; loff_t disksize; int progress = 0; ext4_io_end_t *io_end = mpd->io_submit.io_end; struct ext4_io_end_vec *io_end_vec; io_end_vec = ext4_alloc_io_end_vec(io_end); if (IS_ERR(io_end_vec)) return PTR_ERR(io_end_vec); io_end_vec->offset = ((loff_t)map->m_lblk) << inode->i_blkbits; do { err = mpage_map_one_extent(handle, mpd); if (err < 0) { struct super_block *sb = inode->i_sb; if (ext4_forced_shutdown(sb)) goto invalidate_dirty_pages; /* * Let the uper layers retry transient errors. * In the case of ENOSPC, if ext4_count_free_blocks() * is non-zero, a commit should free up blocks. */ if ((err == -ENOMEM) || (err == -ENOSPC && ext4_count_free_clusters(sb))) { if (progress) goto update_disksize; return err; } ext4_msg(sb, KERN_CRIT, "Delayed block allocation failed for " "inode %lu at logical offset %llu with" " max blocks %u with error %d", inode->i_ino, (unsigned long long)map->m_lblk, (unsigned)map->m_len, -err); ext4_msg(sb, KERN_CRIT, "This should not happen!! Data will " "be lost\n"); if (err == -ENOSPC) ext4_print_free_blocks(inode); invalidate_dirty_pages: *give_up_on_write = true; return err; } progress = 1; /* * Update buffer state, submit mapped pages, and get us new * extent to map */ err = mpage_map_and_submit_buffers(mpd); if (err < 0) goto update_disksize; } while (map->m_len); update_disksize: /* * Update on-disk size after IO is submitted. Races with * truncate are avoided by checking i_size under i_data_sem. */ disksize = ((loff_t)mpd->first_page) << PAGE_SHIFT; if (disksize > READ_ONCE(EXT4_I(inode)->i_disksize)) { int err2; loff_t i_size; down_write(&EXT4_I(inode)->i_data_sem); i_size = i_size_read(inode); if (disksize > i_size) disksize = i_size; if (disksize > EXT4_I(inode)->i_disksize) EXT4_I(inode)->i_disksize = disksize; up_write(&EXT4_I(inode)->i_data_sem); err2 = ext4_mark_inode_dirty(handle, inode); if (err2) { ext4_error_err(inode->i_sb, -err2, "Failed to mark inode %lu dirty", inode->i_ino); } if (!err) err = err2; } return err; } /* * Calculate the total number of credits to reserve for one writepages * iteration. This is called from ext4_writepages(). We map an extent of * up to MAX_WRITEPAGES_EXTENT_LEN blocks and then we go on and finish mapping * the last partial page. So in total we can map MAX_WRITEPAGES_EXTENT_LEN + * bpp - 1 blocks in bpp different extents. */ static int ext4_da_writepages_trans_blocks(struct inode *inode) { int bpp = ext4_journal_blocks_per_page(inode); return ext4_meta_trans_blocks(inode, MAX_WRITEPAGES_EXTENT_LEN + bpp - 1, bpp); } static int ext4_journal_folio_buffers(handle_t *handle, struct folio *folio, size_t len) { struct buffer_head *page_bufs = folio_buffers(folio); struct inode *inode = folio->mapping->host; int ret, err; ret = ext4_walk_page_buffers(handle, inode, page_bufs, 0, len, NULL, do_journal_get_write_access); err = ext4_walk_page_buffers(handle, inode, page_bufs, 0, len, NULL, write_end_fn); if (ret == 0) ret = err; err = ext4_jbd2_inode_add_write(handle, inode, folio_pos(folio), len); if (ret == 0) ret = err; EXT4_I(inode)->i_datasync_tid = handle->h_transaction->t_tid; return ret; } static int mpage_journal_page_buffers(handle_t *handle, struct mpage_da_data *mpd, struct folio *folio) { struct inode *inode = mpd->inode; loff_t size = i_size_read(inode); size_t len = folio_size(folio); folio_clear_checked(folio); mpd->wbc->nr_to_write--; if (folio_pos(folio) + len > size && !ext4_verity_in_progress(inode)) len = size & (len - 1); return ext4_journal_folio_buffers(handle, folio, len); } /* * mpage_prepare_extent_to_map - find & lock contiguous range of dirty pages * needing mapping, submit mapped pages * * @mpd - where to look for pages * * Walk dirty pages in the mapping. If they are fully mapped, submit them for * IO immediately. If we cannot map blocks, we submit just already mapped * buffers in the page for IO and keep page dirty. When we can map blocks and * we find a page which isn't mapped we start accumulating extent of buffers * underlying these pages that needs mapping (formed by either delayed or * unwritten buffers). We also lock the pages containing these buffers. The * extent found is returned in @mpd structure (starting at mpd->lblk with * length mpd->len blocks). * * Note that this function can attach bios to one io_end structure which are * neither logically nor physically contiguous. Although it may seem as an * unnecessary complication, it is actually inevitable in blocksize < pagesize * case as we need to track IO to all buffers underlying a page in one io_end. */ static int mpage_prepare_extent_to_map(struct mpage_da_data *mpd) { struct address_space *mapping = mpd->inode->i_mapping; struct folio_batch fbatch; unsigned int nr_folios; pgoff_t index = mpd->first_page; pgoff_t end = mpd->last_page; xa_mark_t tag; int i, err = 0; int blkbits = mpd->inode->i_blkbits; ext4_lblk_t lblk; struct buffer_head *head; handle_t *handle = NULL; int bpp = ext4_journal_blocks_per_page(mpd->inode); if (mpd->wbc->sync_mode == WB_SYNC_ALL || mpd->wbc->tagged_writepages) tag = PAGECACHE_TAG_TOWRITE; else tag = PAGECACHE_TAG_DIRTY; mpd->map.m_len = 0; mpd->next_page = index; if (ext4_should_journal_data(mpd->inode)) { handle = ext4_journal_start(mpd->inode, EXT4_HT_WRITE_PAGE, bpp); if (IS_ERR(handle)) return PTR_ERR(handle); } folio_batch_init(&fbatch); while (index <= end) { nr_folios = filemap_get_folios_tag(mapping, &index, end, tag, &fbatch); if (nr_folios == 0) break; for (i = 0; i < nr_folios; i++) { struct folio *folio = fbatch.folios[i]; /* * Accumulated enough dirty pages? This doesn't apply * to WB_SYNC_ALL mode. For integrity sync we have to * keep going because someone may be concurrently * dirtying pages, and we might have synced a lot of * newly appeared dirty pages, but have not synced all * of the old dirty pages. */ if (mpd->wbc->sync_mode == WB_SYNC_NONE && mpd->wbc->nr_to_write <= mpd->map.m_len >> (PAGE_SHIFT - blkbits)) goto out; /* If we can't merge this page, we are done. */ if (mpd->map.m_len > 0 && mpd->next_page != folio->index) goto out; if (handle) { err = ext4_journal_ensure_credits(handle, bpp, 0); if (err < 0) goto out; } folio_lock(folio); /* * If the page is no longer dirty, or its mapping no * longer corresponds to inode we are writing (which * means it has been truncated or invalidated), or the * page is already under writeback and we are not doing * a data integrity writeback, skip the page */ if (!folio_test_dirty(folio) || (folio_test_writeback(folio) && (mpd->wbc->sync_mode == WB_SYNC_NONE)) || unlikely(folio->mapping != mapping)) { folio_unlock(folio); continue; } folio_wait_writeback(folio); BUG_ON(folio_test_writeback(folio)); /* * Should never happen but for buggy code in * other subsystems that call * set_page_dirty() without properly warning * the file system first. See [1] for more * information. * * [1] https://lore.kernel.org/linux-mm/20180103100430.GE4911@quack2.suse.cz */ if (!folio_buffers(folio)) { ext4_warning_inode(mpd->inode, "page %lu does not have buffers attached", folio->index); folio_clear_dirty(folio); folio_unlock(folio); continue; } if (mpd->map.m_len == 0) mpd->first_page = folio->index; mpd->next_page = folio_next_index(folio); /* * Writeout when we cannot modify metadata is simple. * Just submit the page. For data=journal mode we * first handle writeout of the page for checkpoint and * only after that handle delayed page dirtying. This * makes sure current data is checkpointed to the final * location before possibly journalling it again which * is desirable when the page is frequently dirtied * through a pin. */ if (!mpd->can_map) { err = mpage_submit_folio(mpd, folio); if (err < 0) goto out; /* Pending dirtying of journalled data? */ if (folio_test_checked(folio)) { err = mpage_journal_page_buffers(handle, mpd, folio); if (err < 0) goto out; mpd->journalled_more_data = 1; } mpage_folio_done(mpd, folio); } else { /* Add all dirty buffers to mpd */ lblk = ((ext4_lblk_t)folio->index) << (PAGE_SHIFT - blkbits); head = folio_buffers(folio); err = mpage_process_page_bufs(mpd, head, head, lblk); if (err <= 0) goto out; err = 0; } } folio_batch_release(&fbatch); cond_resched(); } mpd->scanned_until_end = 1; if (handle) ext4_journal_stop(handle); return 0; out: folio_batch_release(&fbatch); if (handle) ext4_journal_stop(handle); return err; } static int ext4_do_writepages(struct mpage_da_data *mpd) { struct writeback_control *wbc = mpd->wbc; pgoff_t writeback_index = 0; long nr_to_write = wbc->nr_to_write; int range_whole = 0; int cycled = 1; handle_t *handle = NULL; struct inode *inode = mpd->inode; struct address_space *mapping = inode->i_mapping; int needed_blocks, rsv_blocks = 0, ret = 0; struct ext4_sb_info *sbi = EXT4_SB(mapping->host->i_sb); struct blk_plug plug; bool give_up_on_write = false; trace_ext4_writepages(inode, wbc); /* * No pages to write? This is mainly a kludge to avoid starting * a transaction for special inodes like journal inode on last iput() * because that could violate lock ordering on umount */ if (!mapping->nrpages || !mapping_tagged(mapping, PAGECACHE_TAG_DIRTY)) goto out_writepages; /* * If the filesystem has aborted, it is read-only, so return * right away instead of dumping stack traces later on that * will obscure the real source of the problem. We test * fs shutdown state instead of sb->s_flag's SB_RDONLY because * the latter could be true if the filesystem is mounted * read-only, and in that case, ext4_writepages should * *never* be called, so if that ever happens, we would want * the stack trace. */ if (unlikely(ext4_forced_shutdown(mapping->host->i_sb))) { ret = -EROFS; goto out_writepages; } /* * If we have inline data and arrive here, it means that * we will soon create the block for the 1st page, so * we'd better clear the inline data here. */ if (ext4_has_inline_data(inode)) { /* Just inode will be modified... */ handle = ext4_journal_start(inode, EXT4_HT_INODE, 1); if (IS_ERR(handle)) { ret = PTR_ERR(handle); goto out_writepages; } BUG_ON(ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA)); ext4_destroy_inline_data(handle, inode); ext4_journal_stop(handle); } /* * data=journal mode does not do delalloc so we just need to writeout / * journal already mapped buffers. On the other hand we need to commit * transaction to make data stable. We expect all the data to be * already in the journal (the only exception are DMA pinned pages * dirtied behind our back) so we commit transaction here and run the * writeback loop to checkpoint them. The checkpointing is not actually * necessary to make data persistent *but* quite a few places (extent * shifting operations, fsverity, ...) depend on being able to drop * pagecache pages after calling filemap_write_and_wait() and for that * checkpointing needs to happen. */ if (ext4_should_journal_data(inode)) { mpd->can_map = 0; if (wbc->sync_mode == WB_SYNC_ALL) ext4_fc_commit(sbi->s_journal, EXT4_I(inode)->i_datasync_tid); } mpd->journalled_more_data = 0; if (ext4_should_dioread_nolock(inode)) { /* * We may need to convert up to one extent per block in * the page and we may dirty the inode. */ rsv_blocks = 1 + ext4_chunk_trans_blocks(inode, PAGE_SIZE >> inode->i_blkbits); } if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX) range_whole = 1; if (wbc->range_cyclic) { writeback_index = mapping->writeback_index; if (writeback_index) cycled = 0; mpd->first_page = writeback_index; mpd->last_page = -1; } else { mpd->first_page = wbc->range_start >> PAGE_SHIFT; mpd->last_page = wbc->range_end >> PAGE_SHIFT; } ext4_io_submit_init(&mpd->io_submit, wbc); retry: if (wbc->sync_mode == WB_SYNC_ALL || wbc->tagged_writepages) tag_pages_for_writeback(mapping, mpd->first_page, mpd->last_page); blk_start_plug(&plug); /* * First writeback pages that don't need mapping - we can avoid * starting a transaction unnecessarily and also avoid being blocked * in the block layer on device congestion while having transaction * started. */ mpd->do_map = 0; mpd->scanned_until_end = 0; mpd->io_submit.io_end = ext4_init_io_end(inode, GFP_KERNEL); if (!mpd->io_submit.io_end) { ret = -ENOMEM; goto unplug; } ret = mpage_prepare_extent_to_map(mpd); /* Unlock pages we didn't use */ mpage_release_unused_pages(mpd, false); /* Submit prepared bio */ ext4_io_submit(&mpd->io_submit); ext4_put_io_end_defer(mpd->io_submit.io_end); mpd->io_submit.io_end = NULL; if (ret < 0) goto unplug; while (!mpd->scanned_until_end && wbc->nr_to_write > 0) { /* For each extent of pages we use new io_end */ mpd->io_submit.io_end = ext4_init_io_end(inode, GFP_KERNEL); if (!mpd->io_submit.io_end) { ret = -ENOMEM; break; } WARN_ON_ONCE(!mpd->can_map); /* * We have two constraints: We find one extent to map and we * must always write out whole page (makes a difference when * blocksize < pagesize) so that we don't block on IO when we * try to write out the rest of the page. Journalled mode is * not supported by delalloc. */ BUG_ON(ext4_should_journal_data(inode)); needed_blocks = ext4_da_writepages_trans_blocks(inode); /* start a new transaction */ handle = ext4_journal_start_with_reserve(inode, EXT4_HT_WRITE_PAGE, needed_blocks, rsv_blocks); if (IS_ERR(handle)) { ret = PTR_ERR(handle); ext4_msg(inode->i_sb, KERN_CRIT, "%s: jbd2_start: " "%ld pages, ino %lu; err %d", __func__, wbc->nr_to_write, inode->i_ino, ret); /* Release allocated io_end */ ext4_put_io_end(mpd->io_submit.io_end); mpd->io_submit.io_end = NULL; break; } mpd->do_map = 1; trace_ext4_da_write_pages(inode, mpd->first_page, wbc); ret = mpage_prepare_extent_to_map(mpd); if (!ret && mpd->map.m_len) ret = mpage_map_and_submit_extent(handle, mpd, &give_up_on_write); /* * Caution: If the handle is synchronous, * ext4_journal_stop() can wait for transaction commit * to finish which may depend on writeback of pages to * complete or on page lock to be released. In that * case, we have to wait until after we have * submitted all the IO, released page locks we hold, * and dropped io_end reference (for extent conversion * to be able to complete) before stopping the handle. */ if (!ext4_handle_valid(handle) || handle->h_sync == 0) { ext4_journal_stop(handle); handle = NULL; mpd->do_map = 0; } /* Unlock pages we didn't use */ mpage_release_unused_pages(mpd, give_up_on_write); /* Submit prepared bio */ ext4_io_submit(&mpd->io_submit); /* * Drop our io_end reference we got from init. We have * to be careful and use deferred io_end finishing if * we are still holding the transaction as we can * release the last reference to io_end which may end * up doing unwritten extent conversion. */ if (handle) { ext4_put_io_end_defer(mpd->io_submit.io_end); ext4_journal_stop(handle); } else ext4_put_io_end(mpd->io_submit.io_end); mpd->io_submit.io_end = NULL; if (ret == -ENOSPC && sbi->s_journal) { /* * Commit the transaction which would * free blocks released in the transaction * and try again */ jbd2_journal_force_commit_nested(sbi->s_journal); ret = 0; continue; } /* Fatal error - ENOMEM, EIO... */ if (ret) break; } unplug: blk_finish_plug(&plug); if (!ret && !cycled && wbc->nr_to_write > 0) { cycled = 1; mpd->last_page = writeback_index - 1; mpd->first_page = 0; goto retry; } /* Update index */ if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0)) /* * Set the writeback_index so that range_cyclic * mode will write it back later */ mapping->writeback_index = mpd->first_page; out_writepages: trace_ext4_writepages_result(inode, wbc, ret, nr_to_write - wbc->nr_to_write); return ret; } static int ext4_writepages(struct address_space *mapping, struct writeback_control *wbc) { struct super_block *sb = mapping->host->i_sb; struct mpage_da_data mpd = { .inode = mapping->host, .wbc = wbc, .can_map = 1, }; int ret; int alloc_ctx; if (unlikely(ext4_forced_shutdown(sb))) return -EIO; alloc_ctx = ext4_writepages_down_read(sb); ret = ext4_do_writepages(&mpd); /* * For data=journal writeback we could have come across pages marked * for delayed dirtying (PageChecked) which were just added to the * running transaction. Try once more to get them to stable storage. */ if (!ret && mpd.journalled_more_data) ret = ext4_do_writepages(&mpd); ext4_writepages_up_read(sb, alloc_ctx); return ret; } int ext4_normal_submit_inode_data_buffers(struct jbd2_inode *jinode) { struct writeback_control wbc = { .sync_mode = WB_SYNC_ALL, .nr_to_write = LONG_MAX, .range_start = jinode->i_dirty_start, .range_end = jinode->i_dirty_end, }; struct mpage_da_data mpd = { .inode = jinode->i_vfs_inode, .wbc = &wbc, .can_map = 0, }; return ext4_do_writepages(&mpd); } static int ext4_dax_writepages(struct address_space *mapping, struct writeback_control *wbc) { int ret; long nr_to_write = wbc->nr_to_write; struct inode *inode = mapping->host; int alloc_ctx; if (unlikely(ext4_forced_shutdown(inode->i_sb))) return -EIO; alloc_ctx = ext4_writepages_down_read(inode->i_sb); trace_ext4_writepages(inode, wbc); ret = dax_writeback_mapping_range(mapping, EXT4_SB(inode->i_sb)->s_daxdev, wbc); trace_ext4_writepages_result(inode, wbc, ret, nr_to_write - wbc->nr_to_write); ext4_writepages_up_read(inode->i_sb, alloc_ctx); return ret; } static int ext4_nonda_switch(struct super_block *sb) { s64 free_clusters, dirty_clusters; struct ext4_sb_info *sbi = EXT4_SB(sb); /* * switch to non delalloc mode if we are running low * on free block. The free block accounting via percpu * counters can get slightly wrong with percpu_counter_batch getting * accumulated on each CPU without updating global counters * Delalloc need an accurate free block accounting. So switch * to non delalloc when we are near to error range. */ free_clusters = percpu_counter_read_positive(&sbi->s_freeclusters_counter); dirty_clusters = percpu_counter_read_positive(&sbi->s_dirtyclusters_counter); /* * Start pushing delalloc when 1/2 of free blocks are dirty. */ if (dirty_clusters && (free_clusters < 2 * dirty_clusters)) try_to_writeback_inodes_sb(sb, WB_REASON_FS_FREE_SPACE); if (2 * free_clusters < 3 * dirty_clusters || free_clusters < (dirty_clusters + EXT4_FREECLUSTERS_WATERMARK)) { /* * free block count is less than 150% of dirty blocks * or free blocks is less than watermark */ return 1; } return 0; } static int ext4_da_write_begin(struct file *file, struct address_space *mapping, loff_t pos, unsigned len, struct page **pagep, void **fsdata) { int ret, retries = 0; struct folio *folio; pgoff_t index; struct inode *inode = mapping->host; if (unlikely(ext4_forced_shutdown(inode->i_sb))) return -EIO; index = pos >> PAGE_SHIFT; if (ext4_nonda_switch(inode->i_sb) || ext4_verity_in_progress(inode)) { *fsdata = (void *)FALL_BACK_TO_NONDELALLOC; return ext4_write_begin(file, mapping, pos, len, pagep, fsdata); } *fsdata = (void *)0; trace_ext4_da_write_begin(inode, pos, len); if (ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA)) { ret = ext4_da_write_inline_data_begin(mapping, inode, pos, len, pagep, fsdata); if (ret < 0) return ret; if (ret == 1) return 0; } retry: folio = __filemap_get_folio(mapping, index, FGP_WRITEBEGIN, mapping_gfp_mask(mapping)); if (IS_ERR(folio)) return PTR_ERR(folio); #ifdef CONFIG_FS_ENCRYPTION ret = ext4_block_write_begin(folio, pos, len, ext4_da_get_block_prep); #else ret = __block_write_begin(&folio->page, pos, len, ext4_da_get_block_prep); #endif if (ret < 0) { folio_unlock(folio); folio_put(folio); /* * block_write_begin may have instantiated a few blocks * outside i_size. Trim these off again. Don't need * i_size_read because we hold inode lock. */ if (pos + len > inode->i_size) ext4_truncate_failed_write(inode); if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries)) goto retry; return ret; } *pagep = &folio->page; return ret; } /* * Check if we should update i_disksize * when write to the end of file but not require block allocation */ static int ext4_da_should_update_i_disksize(struct folio *folio, unsigned long offset) { struct buffer_head *bh; struct inode *inode = folio->mapping->host; unsigned int idx; int i; bh = folio_buffers(folio); idx = offset >> inode->i_blkbits; for (i = 0; i < idx; i++) bh = bh->b_this_page; if (!buffer_mapped(bh) || (buffer_delay(bh)) || buffer_unwritten(bh)) return 0; return 1; } static int ext4_da_do_write_end(struct address_space *mapping, loff_t pos, unsigned len, unsigned copied, struct folio *folio) { struct inode *inode = mapping->host; loff_t old_size = inode->i_size; bool disksize_changed = false; loff_t new_i_size; if (unlikely(!folio_buffers(folio))) { folio_unlock(folio); folio_put(folio); return -EIO; } /* * block_write_end() will mark the inode as dirty with I_DIRTY_PAGES * flag, which all that's needed to trigger page writeback. */ copied = block_write_end(NULL, mapping, pos, len, copied, &folio->page, NULL); new_i_size = pos + copied; /* * It's important to update i_size while still holding folio lock, * because folio writeout could otherwise come in and zero beyond * i_size. * * Since we are holding inode lock, we are sure i_disksize <= * i_size. We also know that if i_disksize < i_size, there are * delalloc writes pending in the range up to i_size. If the end of * the current write is <= i_size, there's no need to touch * i_disksize since writeback will push i_disksize up to i_size * eventually. If the end of the current write is > i_size and * inside an allocated block which ext4_da_should_update_i_disksize() * checked, we need to update i_disksize here as certain * ext4_writepages() paths not allocating blocks and update i_disksize. */ if (new_i_size > inode->i_size) { unsigned long end; i_size_write(inode, new_i_size); end = (new_i_size - 1) & (PAGE_SIZE - 1); if (copied && ext4_da_should_update_i_disksize(folio, end)) { ext4_update_i_disksize(inode, new_i_size); disksize_changed = true; } } folio_unlock(folio); folio_put(folio); if (old_size < pos) pagecache_isize_extended(inode, old_size, pos); if (disksize_changed) { handle_t *handle; handle = ext4_journal_start(inode, EXT4_HT_INODE, 2); if (IS_ERR(handle)) return PTR_ERR(handle); ext4_mark_inode_dirty(handle, inode); ext4_journal_stop(handle); } return copied; } static int ext4_da_write_end(struct file *file, struct address_space *mapping, loff_t pos, unsigned len, unsigned copied, struct page *page, void *fsdata) { struct inode *inode = mapping->host; int write_mode = (int)(unsigned long)fsdata; struct folio *folio = page_folio(page); if (write_mode == FALL_BACK_TO_NONDELALLOC) return ext4_write_end(file, mapping, pos, len, copied, &folio->page, fsdata); trace_ext4_da_write_end(inode, pos, len, copied); if (write_mode != CONVERT_INLINE_DATA && ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA) && ext4_has_inline_data(inode)) return ext4_write_inline_data_end(inode, pos, len, copied, folio); if (unlikely(copied < len) && !folio_test_uptodate(folio)) copied = 0; return ext4_da_do_write_end(mapping, pos, len, copied, folio); } /* * Force all delayed allocation blocks to be allocated for a given inode. */ int ext4_alloc_da_blocks(struct inode *inode) { trace_ext4_alloc_da_blocks(inode); if (!EXT4_I(inode)->i_reserved_data_blocks) return 0; /* * We do something simple for now. The filemap_flush() will * also start triggering a write of the data blocks, which is * not strictly speaking necessary (and for users of * laptop_mode, not even desirable). However, to do otherwise * would require replicating code paths in: * * ext4_writepages() -> * write_cache_pages() ---> (via passed in callback function) * __mpage_da_writepage() --> * mpage_add_bh_to_extent() * mpage_da_map_blocks() * * The problem is that write_cache_pages(), located in * mm/page-writeback.c, marks pages clean in preparation for * doing I/O, which is not desirable if we're not planning on * doing I/O at all. * * We could call write_cache_pages(), and then redirty all of * the pages by calling redirty_page_for_writepage() but that * would be ugly in the extreme. So instead we would need to * replicate parts of the code in the above functions, * simplifying them because we wouldn't actually intend to * write out the pages, but rather only collect contiguous * logical block extents, call the multi-block allocator, and * then update the buffer heads with the block allocations. * * For now, though, we'll cheat by calling filemap_flush(), * which will map the blocks, and start the I/O, but not * actually wait for the I/O to complete. */ return filemap_flush(inode->i_mapping); } /* * bmap() is special. It gets used by applications such as lilo and by * the swapper to find the on-disk block of a specific piece of data. * * Naturally, this is dangerous if the block concerned is still in the * journal. If somebody makes a swapfile on an ext4 data-journaling * filesystem and enables swap, then they may get a nasty shock when the * data getting swapped to that swapfile suddenly gets overwritten by * the original zero's written out previously to the journal and * awaiting writeback in the kernel's buffer cache. * * So, if we see any bmap calls here on a modified, data-journaled file, * take extra steps to flush any blocks which might be in the cache. */ static sector_t ext4_bmap(struct address_space *mapping, sector_t block) { struct inode *inode = mapping->host; sector_t ret = 0; inode_lock_shared(inode); /* * We can get here for an inline file via the FIBMAP ioctl */ if (ext4_has_inline_data(inode)) goto out; if (mapping_tagged(mapping, PAGECACHE_TAG_DIRTY) && (test_opt(inode->i_sb, DELALLOC) || ext4_should_journal_data(inode))) { /* * With delalloc or journalled data we want to sync the file so * that we can make sure we allocate blocks for file and data * is in place for the user to see it */ filemap_write_and_wait(mapping); } ret = iomap_bmap(mapping, block, &ext4_iomap_ops); out: inode_unlock_shared(inode); return ret; } static int ext4_read_folio(struct file *file, struct folio *folio) { int ret = -EAGAIN; struct inode *inode = folio->mapping->host; trace_ext4_read_folio(inode, folio); if (ext4_has_inline_data(inode)) ret = ext4_readpage_inline(inode, folio); if (ret == -EAGAIN) return ext4_mpage_readpages(inode, NULL, folio); return ret; } static void ext4_readahead(struct readahead_control *rac) { struct inode *inode = rac->mapping->host; /* If the file has inline data, no need to do readahead. */ if (ext4_has_inline_data(inode)) return; ext4_mpage_readpages(inode, rac, NULL); } static void ext4_invalidate_folio(struct folio *folio, size_t offset, size_t length) { trace_ext4_invalidate_folio(folio, offset, length); /* No journalling happens on data buffers when this function is used */ WARN_ON(folio_buffers(folio) && buffer_jbd(folio_buffers(folio))); block_invalidate_folio(folio, offset, length); } static int __ext4_journalled_invalidate_folio(struct folio *folio, size_t offset, size_t length) { journal_t *journal = EXT4_JOURNAL(folio->mapping->host); trace_ext4_journalled_invalidate_folio(folio, offset, length); /* * If it's a full truncate we just forget about the pending dirtying */ if (offset == 0 && length == folio_size(folio)) folio_clear_checked(folio); return jbd2_journal_invalidate_folio(journal, folio, offset, length); } /* Wrapper for aops... */ static void ext4_journalled_invalidate_folio(struct folio *folio, size_t offset, size_t length) { WARN_ON(__ext4_journalled_invalidate_folio(folio, offset, length) < 0); } static bool ext4_release_folio(struct folio *folio, gfp_t wait) { struct inode *inode = folio->mapping->host; journal_t *journal = EXT4_JOURNAL(inode); trace_ext4_release_folio(inode, folio); /* Page has dirty journalled data -> cannot release */ if (folio_test_checked(folio)) return false; if (journal) return jbd2_journal_try_to_free_buffers(journal, folio); else return try_to_free_buffers(folio); } static bool ext4_inode_datasync_dirty(struct inode *inode) { journal_t *journal = EXT4_SB(inode->i_sb)->s_journal; if (journal) { if (jbd2_transaction_committed(journal, EXT4_I(inode)->i_datasync_tid)) return false; if (test_opt2(inode->i_sb, JOURNAL_FAST_COMMIT)) return !list_empty(&EXT4_I(inode)->i_fc_list); return true; } /* Any metadata buffers to write? */ if (!list_empty(&inode->i_mapping->i_private_list)) return true; return inode->i_state & I_DIRTY_DATASYNC; } static void ext4_set_iomap(struct inode *inode, struct iomap *iomap, struct ext4_map_blocks *map, loff_t offset, loff_t length, unsigned int flags) { u8 blkbits = inode->i_blkbits; /* * Writes that span EOF might trigger an I/O size update on completion, * so consider them to be dirty for the purpose of O_DSYNC, even if * there is no other metadata changes being made or are pending. */ iomap->flags = 0; if (ext4_inode_datasync_dirty(inode) || offset + length > i_size_read(inode)) iomap->flags |= IOMAP_F_DIRTY; if (map->m_flags & EXT4_MAP_NEW) iomap->flags |= IOMAP_F_NEW; if (flags & IOMAP_DAX) iomap->dax_dev = EXT4_SB(inode->i_sb)->s_daxdev; else iomap->bdev = inode->i_sb->s_bdev; iomap->offset = (u64) map->m_lblk << blkbits; iomap->length = (u64) map->m_len << blkbits; if ((map->m_flags & EXT4_MAP_MAPPED) && !ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) iomap->flags |= IOMAP_F_MERGED; /* * Flags passed to ext4_map_blocks() for direct I/O writes can result * in m_flags having both EXT4_MAP_MAPPED and EXT4_MAP_UNWRITTEN bits * set. In order for any allocated unwritten extents to be converted * into written extents correctly within the ->end_io() handler, we * need to ensure that the iomap->type is set appropriately. Hence, the * reason why we need to check whether the EXT4_MAP_UNWRITTEN bit has * been set first. */ if (map->m_flags & EXT4_MAP_UNWRITTEN) { iomap->type = IOMAP_UNWRITTEN; iomap->addr = (u64) map->m_pblk << blkbits; if (flags & IOMAP_DAX) iomap->addr += EXT4_SB(inode->i_sb)->s_dax_part_off; } else if (map->m_flags & EXT4_MAP_MAPPED) { iomap->type = IOMAP_MAPPED; iomap->addr = (u64) map->m_pblk << blkbits; if (flags & IOMAP_DAX) iomap->addr += EXT4_SB(inode->i_sb)->s_dax_part_off; } else if (map->m_flags & EXT4_MAP_DELAYED) { iomap->type = IOMAP_DELALLOC; iomap->addr = IOMAP_NULL_ADDR; } else { iomap->type = IOMAP_HOLE; iomap->addr = IOMAP_NULL_ADDR; } } static int ext4_iomap_alloc(struct inode *inode, struct ext4_map_blocks *map, unsigned int flags) { handle_t *handle; u8 blkbits = inode->i_blkbits; int ret, dio_credits, m_flags = 0, retries = 0; /* * Trim the mapping request to the maximum value that we can map at * once for direct I/O. */ if (map->m_len > DIO_MAX_BLOCKS) map->m_len = DIO_MAX_BLOCKS; dio_credits = ext4_chunk_trans_blocks(inode, map->m_len); retry: /* * Either we allocate blocks and then don't get an unwritten extent, so * in that case we have reserved enough credits. Or, the blocks are * already allocated and unwritten. In that case, the extent conversion * fits into the credits as well. */ handle = ext4_journal_start(inode, EXT4_HT_MAP_BLOCKS, dio_credits); if (IS_ERR(handle)) return PTR_ERR(handle); /* * DAX and direct I/O are the only two operations that are currently * supported with IOMAP_WRITE. */ WARN_ON(!(flags & (IOMAP_DAX | IOMAP_DIRECT))); if (flags & IOMAP_DAX) m_flags = EXT4_GET_BLOCKS_CREATE_ZERO; /* * We use i_size instead of i_disksize here because delalloc writeback * can complete at any point during the I/O and subsequently push the * i_disksize out to i_size. This could be beyond where direct I/O is * happening and thus expose allocated blocks to direct I/O reads. */ else if (((loff_t)map->m_lblk << blkbits) >= i_size_read(inode)) m_flags = EXT4_GET_BLOCKS_CREATE; else if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) m_flags = EXT4_GET_BLOCKS_IO_CREATE_EXT; ret = ext4_map_blocks(handle, inode, map, m_flags); /* * We cannot fill holes in indirect tree based inodes as that could * expose stale data in the case of a crash. Use the magic error code * to fallback to buffered I/O. */ if (!m_flags && !ret) ret = -ENOTBLK; ext4_journal_stop(handle); if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries)) goto retry; return ret; } static int ext4_iomap_begin(struct inode *inode, loff_t offset, loff_t length, unsigned flags, struct iomap *iomap, struct iomap *srcmap) { int ret; struct ext4_map_blocks map; u8 blkbits = inode->i_blkbits; if ((offset >> blkbits) > EXT4_MAX_LOGICAL_BLOCK) return -EINVAL; if (WARN_ON_ONCE(ext4_has_inline_data(inode))) return -ERANGE; /* * Calculate the first and last logical blocks respectively. */ map.m_lblk = offset >> blkbits; map.m_len = min_t(loff_t, (offset + length - 1) >> blkbits, EXT4_MAX_LOGICAL_BLOCK) - map.m_lblk + 1; if (flags & IOMAP_WRITE) { /* * We check here if the blocks are already allocated, then we * don't need to start a journal txn and we can directly return * the mapping information. This could boost performance * especially in multi-threaded overwrite requests. */ if (offset + length <= i_size_read(inode)) { ret = ext4_map_blocks(NULL, inode, &map, 0); if (ret > 0 && (map.m_flags & EXT4_MAP_MAPPED)) goto out; } ret = ext4_iomap_alloc(inode, &map, flags); } else { ret = ext4_map_blocks(NULL, inode, &map, 0); } if (ret < 0) return ret; out: /* * When inline encryption is enabled, sometimes I/O to an encrypted file * has to be broken up to guarantee DUN contiguity. Handle this by * limiting the length of the mapping returned. */ map.m_len = fscrypt_limit_io_blocks(inode, map.m_lblk, map.m_len); ext4_set_iomap(inode, iomap, &map, offset, length, flags); return 0; } static int ext4_iomap_overwrite_begin(struct inode *inode, loff_t offset, loff_t length, unsigned flags, struct iomap *iomap, struct iomap *srcmap) { int ret; /* * Even for writes we don't need to allocate blocks, so just pretend * we are reading to save overhead of starting a transaction. */ flags &= ~IOMAP_WRITE; ret = ext4_iomap_begin(inode, offset, length, flags, iomap, srcmap); WARN_ON_ONCE(!ret && iomap->type != IOMAP_MAPPED); return ret; } static int ext4_iomap_end(struct inode *inode, loff_t offset, loff_t length, ssize_t written, unsigned flags, struct iomap *iomap) { /* * Check to see whether an error occurred while writing out the data to * the allocated blocks. If so, return the magic error code so that we * fallback to buffered I/O and attempt to complete the remainder of * the I/O. Any blocks that may have been allocated in preparation for * the direct I/O will be reused during buffered I/O. */ if (flags & (IOMAP_WRITE | IOMAP_DIRECT) && written == 0) return -ENOTBLK; return 0; } const struct iomap_ops ext4_iomap_ops = { .iomap_begin = ext4_iomap_begin, .iomap_end = ext4_iomap_end, }; const struct iomap_ops ext4_iomap_overwrite_ops = { .iomap_begin = ext4_iomap_overwrite_begin, .iomap_end = ext4_iomap_end, }; static int ext4_iomap_begin_report(struct inode *inode, loff_t offset, loff_t length, unsigned int flags, struct iomap *iomap, struct iomap *srcmap) { int ret; struct ext4_map_blocks map; u8 blkbits = inode->i_blkbits; if ((offset >> blkbits) > EXT4_MAX_LOGICAL_BLOCK) return -EINVAL; if (ext4_has_inline_data(inode)) { ret = ext4_inline_data_iomap(inode, iomap); if (ret != -EAGAIN) { if (ret == 0 && offset >= iomap->length) ret = -ENOENT; return ret; } } /* * Calculate the first and last logical block respectively. */ map.m_lblk = offset >> blkbits; map.m_len = min_t(loff_t, (offset + length - 1) >> blkbits, EXT4_MAX_LOGICAL_BLOCK) - map.m_lblk + 1; /* * Fiemap callers may call for offset beyond s_bitmap_maxbytes. * So handle it here itself instead of querying ext4_map_blocks(). * Since ext4_map_blocks() will warn about it and will return * -EIO error. */ if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) { struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); if (offset >= sbi->s_bitmap_maxbytes) { map.m_flags = 0; goto set_iomap; } } ret = ext4_map_blocks(NULL, inode, &map, 0); if (ret < 0) return ret; set_iomap: ext4_set_iomap(inode, iomap, &map, offset, length, flags); return 0; } const struct iomap_ops ext4_iomap_report_ops = { .iomap_begin = ext4_iomap_begin_report, }; /* * For data=journal mode, folio should be marked dirty only when it was * writeably mapped. When that happens, it was already attached to the * transaction and marked as jbddirty (we take care of this in * ext4_page_mkwrite()). On transaction commit, we writeprotect page mappings * so we should have nothing to do here, except for the case when someone * had the page pinned and dirtied the page through this pin (e.g. by doing * direct IO to it). In that case we'd need to attach buffers here to the * transaction but we cannot due to lock ordering. We cannot just dirty the * folio and leave attached buffers clean, because the buffers' dirty state is * "definitive". We cannot just set the buffers dirty or jbddirty because all * the journalling code will explode. So what we do is to mark the folio * "pending dirty" and next time ext4_writepages() is called, attach buffers * to the transaction appropriately. */ static bool ext4_journalled_dirty_folio(struct address_space *mapping, struct folio *folio) { WARN_ON_ONCE(!folio_buffers(folio)); if (folio_maybe_dma_pinned(folio)) folio_set_checked(folio); return filemap_dirty_folio(mapping, folio); } static bool ext4_dirty_folio(struct address_space *mapping, struct folio *folio) { WARN_ON_ONCE(!folio_test_locked(folio) && !folio_test_dirty(folio)); WARN_ON_ONCE(!folio_buffers(folio)); return block_dirty_folio(mapping, folio); } static int ext4_iomap_swap_activate(struct swap_info_struct *sis, struct file *file, sector_t *span) { return iomap_swapfile_activate(sis, file, span, &ext4_iomap_report_ops); } static const struct address_space_operations ext4_aops = { .read_folio = ext4_read_folio, .readahead = ext4_readahead, .writepages = ext4_writepages, .write_begin = ext4_write_begin, .write_end = ext4_write_end, .dirty_folio = ext4_dirty_folio, .bmap = ext4_bmap, .invalidate_folio = ext4_invalidate_folio, .release_folio = ext4_release_folio, .migrate_folio = buffer_migrate_folio, .is_partially_uptodate = block_is_partially_uptodate, .error_remove_folio = generic_error_remove_folio, .swap_activate = ext4_iomap_swap_activate, }; static const struct address_space_operations ext4_journalled_aops = { .read_folio = ext4_read_folio, .readahead = ext4_readahead, .writepages = ext4_writepages, .write_begin = ext4_write_begin, .write_end = ext4_journalled_write_end, .dirty_folio = ext4_journalled_dirty_folio, .bmap = ext4_bmap, .invalidate_folio = ext4_journalled_invalidate_folio, .release_folio = ext4_release_folio, .migrate_folio = buffer_migrate_folio_norefs, .is_partially_uptodate = block_is_partially_uptodate, .error_remove_folio = generic_error_remove_folio, .swap_activate = ext4_iomap_swap_activate, }; static const struct address_space_operations ext4_da_aops = { .read_folio = ext4_read_folio, .readahead = ext4_readahead, .writepages = ext4_writepages, .write_begin = ext4_da_write_begin, .write_end = ext4_da_write_end, .dirty_folio = ext4_dirty_folio, .bmap = ext4_bmap, .invalidate_folio = ext4_invalidate_folio, .release_folio = ext4_release_folio, .migrate_folio = buffer_migrate_folio, .is_partially_uptodate = block_is_partially_uptodate, .error_remove_folio = generic_error_remove_folio, .swap_activate = ext4_iomap_swap_activate, }; static const struct address_space_operations ext4_dax_aops = { .writepages = ext4_dax_writepages, .dirty_folio = noop_dirty_folio, .bmap = ext4_bmap, .swap_activate = ext4_iomap_swap_activate, }; void ext4_set_aops(struct inode *inode) { switch (ext4_inode_journal_mode(inode)) { case EXT4_INODE_ORDERED_DATA_MODE: case EXT4_INODE_WRITEBACK_DATA_MODE: break; case EXT4_INODE_JOURNAL_DATA_MODE: inode->i_mapping->a_ops = &ext4_journalled_aops; return; default: BUG(); } if (IS_DAX(inode)) inode->i_mapping->a_ops = &ext4_dax_aops; else if (test_opt(inode->i_sb, DELALLOC)) inode->i_mapping->a_ops = &ext4_da_aops; else inode->i_mapping->a_ops = &ext4_aops; } /* * Here we can't skip an unwritten buffer even though it usually reads zero * because it might have data in pagecache (eg, if called from ext4_zero_range, * ext4_punch_hole, etc) which needs to be properly zeroed out. Otherwise a * racing writeback can come later and flush the stale pagecache to disk. */ static int __ext4_block_zero_page_range(handle_t *handle, struct address_space *mapping, loff_t from, loff_t length) { ext4_fsblk_t index = from >> PAGE_SHIFT; unsigned offset = from & (PAGE_SIZE-1); unsigned blocksize, pos; ext4_lblk_t iblock; struct inode *inode = mapping->host; struct buffer_head *bh; struct folio *folio; int err = 0; folio = __filemap_get_folio(mapping, from >> PAGE_SHIFT, FGP_LOCK | FGP_ACCESSED | FGP_CREAT, mapping_gfp_constraint(mapping, ~__GFP_FS)); if (IS_ERR(folio)) return PTR_ERR(folio); blocksize = inode->i_sb->s_blocksize; iblock = index << (PAGE_SHIFT - inode->i_sb->s_blocksize_bits); bh = folio_buffers(folio); if (!bh) bh = create_empty_buffers(folio, blocksize, 0); /* Find the buffer that contains "offset" */ pos = blocksize; while (offset >= pos) { bh = bh->b_this_page; iblock++; pos += blocksize; } if (buffer_freed(bh)) { BUFFER_TRACE(bh, "freed: skip"); goto unlock; } if (!buffer_mapped(bh)) { BUFFER_TRACE(bh, "unmapped"); ext4_get_block(inode, iblock, bh, 0); /* unmapped? It's a hole - nothing to do */ if (!buffer_mapped(bh)) { BUFFER_TRACE(bh, "still unmapped"); goto unlock; } } /* Ok, it's mapped. Make sure it's up-to-date */ if (folio_test_uptodate(folio)) set_buffer_uptodate(bh); if (!buffer_uptodate(bh)) { err = ext4_read_bh_lock(bh, 0, true); if (err) goto unlock; if (fscrypt_inode_uses_fs_layer_crypto(inode)) { /* We expect the key to be set. */ BUG_ON(!fscrypt_has_encryption_key(inode)); err = fscrypt_decrypt_pagecache_blocks(folio, blocksize, bh_offset(bh)); if (err) { clear_buffer_uptodate(bh); goto unlock; } } } if (ext4_should_journal_data(inode)) { BUFFER_TRACE(bh, "get write access"); err = ext4_journal_get_write_access(handle, inode->i_sb, bh, EXT4_JTR_NONE); if (err) goto unlock; } folio_zero_range(folio, offset, length); BUFFER_TRACE(bh, "zeroed end of block"); if (ext4_should_journal_data(inode)) { err = ext4_dirty_journalled_data(handle, bh); } else { err = 0; mark_buffer_dirty(bh); if (ext4_should_order_data(inode)) err = ext4_jbd2_inode_add_write(handle, inode, from, length); } unlock: folio_unlock(folio); folio_put(folio); return err; } /* * ext4_block_zero_page_range() zeros out a mapping of length 'length' * starting from file offset 'from'. The range to be zero'd must * be contained with in one block. If the specified range exceeds * the end of the block it will be shortened to end of the block * that corresponds to 'from' */ static int ext4_block_zero_page_range(handle_t *handle, struct address_space *mapping, loff_t from, loff_t length) { struct inode *inode = mapping->host; unsigned offset = from & (PAGE_SIZE-1); unsigned blocksize = inode->i_sb->s_blocksize; unsigned max = blocksize - (offset & (blocksize - 1)); /* * correct length if it does not fall between * 'from' and the end of the block */ if (length > max || length < 0) length = max; if (IS_DAX(inode)) { return dax_zero_range(inode, from, length, NULL, &ext4_iomap_ops); } return __ext4_block_zero_page_range(handle, mapping, from, length); } /* * ext4_block_truncate_page() zeroes out a mapping from file offset `from' * up to the end of the block which corresponds to `from'. * This required during truncate. We need to physically zero the tail end * of that block so it doesn't yield old data if the file is later grown. */ static int ext4_block_truncate_page(handle_t *handle, struct address_space *mapping, loff_t from) { unsigned offset = from & (PAGE_SIZE-1); unsigned length; unsigned blocksize; struct inode *inode = mapping->host; /* If we are processing an encrypted inode during orphan list handling */ if (IS_ENCRYPTED(inode) && !fscrypt_has_encryption_key(inode)) return 0; blocksize = inode->i_sb->s_blocksize; length = blocksize - (offset & (blocksize - 1)); return ext4_block_zero_page_range(handle, mapping, from, length); } int ext4_zero_partial_blocks(handle_t *handle, struct inode *inode, loff_t lstart, loff_t length) { struct super_block *sb = inode->i_sb; struct address_space *mapping = inode->i_mapping; unsigned partial_start, partial_end; ext4_fsblk_t start, end; loff_t byte_end = (lstart + length - 1); int err = 0; partial_start = lstart & (sb->s_blocksize - 1); partial_end = byte_end & (sb->s_blocksize - 1); start = lstart >> sb->s_blocksize_bits; end = byte_end >> sb->s_blocksize_bits; /* Handle partial zero within the single block */ if (start == end && (partial_start || (partial_end != sb->s_blocksize - 1))) { err = ext4_block_zero_page_range(handle, mapping, lstart, length); return err; } /* Handle partial zero out on the start of the range */ if (partial_start) { err = ext4_block_zero_page_range(handle, mapping, lstart, sb->s_blocksize); if (err) return err; } /* Handle partial zero out on the end of the range */ if (partial_end != sb->s_blocksize - 1) err = ext4_block_zero_page_range(handle, mapping, byte_end - partial_end, partial_end + 1); return err; } int ext4_can_truncate(struct inode *inode) { if (S_ISREG(inode->i_mode)) return 1; if (S_ISDIR(inode->i_mode)) return 1; if (S_ISLNK(inode->i_mode)) return !ext4_inode_is_fast_symlink(inode); return 0; } /* * We have to make sure i_disksize gets properly updated before we truncate * page cache due to hole punching or zero range. Otherwise i_disksize update * can get lost as it may have been postponed to submission of writeback but * that will never happen after we truncate page cache. */ int ext4_update_disksize_before_punch(struct inode *inode, loff_t offset, loff_t len) { handle_t *handle; int ret; loff_t size = i_size_read(inode); WARN_ON(!inode_is_locked(inode)); if (offset > size || offset + len < size) return 0; if (EXT4_I(inode)->i_disksize >= size) return 0; handle = ext4_journal_start(inode, EXT4_HT_MISC, 1); if (IS_ERR(handle)) return PTR_ERR(handle); ext4_update_i_disksize(inode, size); ret = ext4_mark_inode_dirty(handle, inode); ext4_journal_stop(handle); return ret; } static void ext4_wait_dax_page(struct inode *inode) { filemap_invalidate_unlock(inode->i_mapping); schedule(); filemap_invalidate_lock(inode->i_mapping); } int ext4_break_layouts(struct inode *inode) { struct page *page; int error; if (WARN_ON_ONCE(!rwsem_is_locked(&inode->i_mapping->invalidate_lock))) return -EINVAL; do { page = dax_layout_busy_page(inode->i_mapping); if (!page) return 0; error = ___wait_var_event(&page->_refcount, atomic_read(&page->_refcount) == 1, TASK_INTERRUPTIBLE, 0, 0, ext4_wait_dax_page(inode)); } while (error == 0); return error; } /* * ext4_punch_hole: punches a hole in a file by releasing the blocks * associated with the given offset and length * * @inode: File inode * @offset: The offset where the hole will begin * @len: The length of the hole * * Returns: 0 on success or negative on failure */ int ext4_punch_hole(struct file *file, loff_t offset, loff_t length) { struct inode *inode = file_inode(file); struct super_block *sb = inode->i_sb; ext4_lblk_t first_block, stop_block; struct address_space *mapping = inode->i_mapping; loff_t first_block_offset, last_block_offset, max_length; struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); handle_t *handle; unsigned int credits; int ret = 0, ret2 = 0; trace_ext4_punch_hole(inode, offset, length, 0); /* * Write out all dirty pages to avoid race conditions * Then release them. */ if (mapping_tagged(mapping, PAGECACHE_TAG_DIRTY)) { ret = filemap_write_and_wait_range(mapping, offset, offset + length - 1); if (ret) return ret; } inode_lock(inode); /* No need to punch hole beyond i_size */ if (offset >= inode->i_size) goto out_mutex; /* * If the hole extends beyond i_size, set the hole * to end after the page that contains i_size */ if (offset + length > inode->i_size) { length = inode->i_size + PAGE_SIZE - (inode->i_size & (PAGE_SIZE - 1)) - offset; } /* * For punch hole the length + offset needs to be within one block * before last range. Adjust the length if it goes beyond that limit. */ max_length = sbi->s_bitmap_maxbytes - inode->i_sb->s_blocksize; if (offset + length > max_length) length = max_length - offset; if (offset & (sb->s_blocksize - 1) || (offset + length) & (sb->s_blocksize - 1)) { /* * Attach jinode to inode for jbd2 if we do any zeroing of * partial block */ ret = ext4_inode_attach_jinode(inode); if (ret < 0) goto out_mutex; } /* Wait all existing dio workers, newcomers will block on i_rwsem */ inode_dio_wait(inode); ret = file_modified(file); if (ret) goto out_mutex; /* * Prevent page faults from reinstantiating pages we have released from * page cache. */ filemap_invalidate_lock(mapping); ret = ext4_break_layouts(inode); if (ret) goto out_dio; first_block_offset = round_up(offset, sb->s_blocksize); last_block_offset = round_down((offset + length), sb->s_blocksize) - 1; /* Now release the pages and zero block aligned part of pages*/ if (last_block_offset > first_block_offset) { ret = ext4_update_disksize_before_punch(inode, offset, length); if (ret) goto out_dio; truncate_pagecache_range(inode, first_block_offset, last_block_offset); } if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) credits = ext4_writepage_trans_blocks(inode); else credits = ext4_blocks_for_truncate(inode); handle = ext4_journal_start(inode, EXT4_HT_TRUNCATE, credits); if (IS_ERR(handle)) { ret = PTR_ERR(handle); ext4_std_error(sb, ret); goto out_dio; } ret = ext4_zero_partial_blocks(handle, inode, offset, length); if (ret) goto out_stop; first_block = (offset + sb->s_blocksize - 1) >> EXT4_BLOCK_SIZE_BITS(sb); stop_block = (offset + length) >> EXT4_BLOCK_SIZE_BITS(sb); /* If there are blocks to remove, do it */ if (stop_block > first_block) { ext4_lblk_t hole_len = stop_block - first_block; down_write(&EXT4_I(inode)->i_data_sem); ext4_discard_preallocations(inode); ext4_es_remove_extent(inode, first_block, hole_len); if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) ret = ext4_ext_remove_space(inode, first_block, stop_block - 1); else ret = ext4_ind_remove_space(handle, inode, first_block, stop_block); ext4_es_insert_extent(inode, first_block, hole_len, ~0, EXTENT_STATUS_HOLE); up_write(&EXT4_I(inode)->i_data_sem); } ext4_fc_track_range(handle, inode, first_block, stop_block); if (IS_SYNC(inode)) ext4_handle_sync(handle); inode_set_mtime_to_ts(inode, inode_set_ctime_current(inode)); ret2 = ext4_mark_inode_dirty(handle, inode); if (unlikely(ret2)) ret = ret2; if (ret >= 0) ext4_update_inode_fsync_trans(handle, inode, 1); out_stop: ext4_journal_stop(handle); out_dio: filemap_invalidate_unlock(mapping); out_mutex: inode_unlock(inode); return ret; } int ext4_inode_attach_jinode(struct inode *inode) { struct ext4_inode_info *ei = EXT4_I(inode); struct jbd2_inode *jinode; if (ei->jinode || !EXT4_SB(inode->i_sb)->s_journal) return 0; jinode = jbd2_alloc_inode(GFP_KERNEL); spin_lock(&inode->i_lock); if (!ei->jinode) { if (!jinode) { spin_unlock(&inode->i_lock); return -ENOMEM; } ei->jinode = jinode; jbd2_journal_init_jbd_inode(ei->jinode, inode); jinode = NULL; } spin_unlock(&inode->i_lock); if (unlikely(jinode != NULL)) jbd2_free_inode(jinode); return 0; } /* * ext4_truncate() * * We block out ext4_get_block() block instantiations across the entire * transaction, and VFS/VM ensures that ext4_truncate() cannot run * simultaneously on behalf of the same inode. * * As we work through the truncate and commit bits of it to the journal there * is one core, guiding principle: the file's tree must always be consistent on * disk. We must be able to restart the truncate after a crash. * * The file's tree may be transiently inconsistent in memory (although it * probably isn't), but whenever we close off and commit a journal transaction, * the contents of (the filesystem + the journal) must be consistent and * restartable. It's pretty simple, really: bottom up, right to left (although * left-to-right works OK too). * * Note that at recovery time, journal replay occurs *before* the restart of * truncate against the orphan inode list. * * The committed inode has the new, desired i_size (which is the same as * i_disksize in this case). After a crash, ext4_orphan_cleanup() will see * that this inode's truncate did not complete and it will again call * ext4_truncate() to have another go. So there will be instantiated blocks * to the right of the truncation point in a crashed ext4 filesystem. But * that's fine - as long as they are linked from the inode, the post-crash * ext4_truncate() run will find them and release them. */ int ext4_truncate(struct inode *inode) { struct ext4_inode_info *ei = EXT4_I(inode); unsigned int credits; int err = 0, err2; handle_t *handle; struct address_space *mapping = inode->i_mapping; /* * There is a possibility that we're either freeing the inode * or it's a completely new inode. In those cases we might not * have i_rwsem locked because it's not necessary. */ if (!(inode->i_state & (I_NEW|I_FREEING))) WARN_ON(!inode_is_locked(inode)); trace_ext4_truncate_enter(inode); if (!ext4_can_truncate(inode)) goto out_trace; if (inode->i_size == 0 && !test_opt(inode->i_sb, NO_AUTO_DA_ALLOC)) ext4_set_inode_state(inode, EXT4_STATE_DA_ALLOC_CLOSE); if (ext4_has_inline_data(inode)) { int has_inline = 1; err = ext4_inline_data_truncate(inode, &has_inline); if (err || has_inline) goto out_trace; } /* If we zero-out tail of the page, we have to create jinode for jbd2 */ if (inode->i_size & (inode->i_sb->s_blocksize - 1)) { err = ext4_inode_attach_jinode(inode); if (err) goto out_trace; } if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) credits = ext4_writepage_trans_blocks(inode); else credits = ext4_blocks_for_truncate(inode); handle = ext4_journal_start(inode, EXT4_HT_TRUNCATE, credits); if (IS_ERR(handle)) { err = PTR_ERR(handle); goto out_trace; } if (inode->i_size & (inode->i_sb->s_blocksize - 1)) ext4_block_truncate_page(handle, mapping, inode->i_size); /* * We add the inode to the orphan list, so that if this * truncate spans multiple transactions, and we crash, we will * resume the truncate when the filesystem recovers. It also * marks the inode dirty, to catch the new size. * * Implication: the file must always be in a sane, consistent * truncatable state while each transaction commits. */ err = ext4_orphan_add(handle, inode); if (err) goto out_stop; down_write(&EXT4_I(inode)->i_data_sem); ext4_discard_preallocations(inode); if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) err = ext4_ext_truncate(handle, inode); else ext4_ind_truncate(handle, inode); up_write(&ei->i_data_sem); if (err) goto out_stop; if (IS_SYNC(inode)) ext4_handle_sync(handle); out_stop: /* * If this was a simple ftruncate() and the file will remain alive, * then we need to clear up the orphan record which we created above. * However, if this was a real unlink then we were called by * ext4_evict_inode(), and we allow that function to clean up the * orphan info for us. */ if (inode->i_nlink) ext4_orphan_del(handle, inode); inode_set_mtime_to_ts(inode, inode_set_ctime_current(inode)); err2 = ext4_mark_inode_dirty(handle, inode); if (unlikely(err2 && !err)) err = err2; ext4_journal_stop(handle); out_trace: trace_ext4_truncate_exit(inode); return err; } static inline u64 ext4_inode_peek_iversion(const struct inode *inode) { if (unlikely(EXT4_I(inode)->i_flags & EXT4_EA_INODE_FL)) return inode_peek_iversion_raw(inode); else return inode_peek_iversion(inode); } static int ext4_inode_blocks_set(struct ext4_inode *raw_inode, struct ext4_inode_info *ei) { struct inode *inode = &(ei->vfs_inode); u64 i_blocks = READ_ONCE(inode->i_blocks); struct super_block *sb = inode->i_sb; if (i_blocks <= ~0U) { /* * i_blocks can be represented in a 32 bit variable * as multiple of 512 bytes */ raw_inode->i_blocks_lo = cpu_to_le32(i_blocks); raw_inode->i_blocks_high = 0; ext4_clear_inode_flag(inode, EXT4_INODE_HUGE_FILE); return 0; } /* * This should never happen since sb->s_maxbytes should not have * allowed this, sb->s_maxbytes was set according to the huge_file * feature in ext4_fill_super(). */ if (!ext4_has_feature_huge_file(sb)) return -EFSCORRUPTED; if (i_blocks <= 0xffffffffffffULL) { /* * i_blocks can be represented in a 48 bit variable * as multiple of 512 bytes */ raw_inode->i_blocks_lo = cpu_to_le32(i_blocks); raw_inode->i_blocks_high = cpu_to_le16(i_blocks >> 32); ext4_clear_inode_flag(inode, EXT4_INODE_HUGE_FILE); } else { ext4_set_inode_flag(inode, EXT4_INODE_HUGE_FILE); /* i_block is stored in file system block size */ i_blocks = i_blocks >> (inode->i_blkbits - 9); raw_inode->i_blocks_lo = cpu_to_le32(i_blocks); raw_inode->i_blocks_high = cpu_to_le16(i_blocks >> 32); } return 0; } static int ext4_fill_raw_inode(struct inode *inode, struct ext4_inode *raw_inode) { struct ext4_inode_info *ei = EXT4_I(inode); uid_t i_uid; gid_t i_gid; projid_t i_projid; int block; int err; err = ext4_inode_blocks_set(raw_inode, ei); raw_inode->i_mode = cpu_to_le16(inode->i_mode); i_uid = i_uid_read(inode); i_gid = i_gid_read(inode); i_projid = from_kprojid(&init_user_ns, ei->i_projid); if (!(test_opt(inode->i_sb, NO_UID32))) { raw_inode->i_uid_low = cpu_to_le16(low_16_bits(i_uid)); raw_inode->i_gid_low = cpu_to_le16(low_16_bits(i_gid)); /* * Fix up interoperability with old kernels. Otherwise, * old inodes get re-used with the upper 16 bits of the * uid/gid intact. */ if (ei->i_dtime && list_empty(&ei->i_orphan)) { raw_inode->i_uid_high = 0; raw_inode->i_gid_high = 0; } else { raw_inode->i_uid_high = cpu_to_le16(high_16_bits(i_uid)); raw_inode->i_gid_high = cpu_to_le16(high_16_bits(i_gid)); } } else { raw_inode->i_uid_low = cpu_to_le16(fs_high2lowuid(i_uid)); raw_inode->i_gid_low = cpu_to_le16(fs_high2lowgid(i_gid)); raw_inode->i_uid_high = 0; raw_inode->i_gid_high = 0; } raw_inode->i_links_count = cpu_to_le16(inode->i_nlink); EXT4_INODE_SET_CTIME(inode, raw_inode); EXT4_INODE_SET_MTIME(inode, raw_inode); EXT4_INODE_SET_ATIME(inode, raw_inode); EXT4_EINODE_SET_XTIME(i_crtime, ei, raw_inode); raw_inode->i_dtime = cpu_to_le32(ei->i_dtime); raw_inode->i_flags = cpu_to_le32(ei->i_flags & 0xFFFFFFFF); if (likely(!test_opt2(inode->i_sb, HURD_COMPAT))) raw_inode->i_file_acl_high = cpu_to_le16(ei->i_file_acl >> 32); raw_inode->i_file_acl_lo = cpu_to_le32(ei->i_file_acl); ext4_isize_set(raw_inode, ei->i_disksize); raw_inode->i_generation = cpu_to_le32(inode->i_generation); if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) { if (old_valid_dev(inode->i_rdev)) { raw_inode->i_block[0] = cpu_to_le32(old_encode_dev(inode->i_rdev)); raw_inode->i_block[1] = 0; } else { raw_inode->i_block[0] = 0; raw_inode->i_block[1] = cpu_to_le32(new_encode_dev(inode->i_rdev)); raw_inode->i_block[2] = 0; } } else if (!ext4_has_inline_data(inode)) { for (block = 0; block < EXT4_N_BLOCKS; block++) raw_inode->i_block[block] = ei->i_data[block]; } if (likely(!test_opt2(inode->i_sb, HURD_COMPAT))) { u64 ivers = ext4_inode_peek_iversion(inode); raw_inode->i_disk_version = cpu_to_le32(ivers); if (ei->i_extra_isize) { if (EXT4_FITS_IN_INODE(raw_inode, ei, i_version_hi)) raw_inode->i_version_hi = cpu_to_le32(ivers >> 32); raw_inode->i_extra_isize = cpu_to_le16(ei->i_extra_isize); } } if (i_projid != EXT4_DEF_PROJID && !ext4_has_feature_project(inode->i_sb)) err = err ?: -EFSCORRUPTED; if (EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE && EXT4_FITS_IN_INODE(raw_inode, ei, i_projid)) raw_inode->i_projid = cpu_to_le32(i_projid); ext4_inode_csum_set(inode, raw_inode, ei); return err; } /* * ext4_get_inode_loc returns with an extra refcount against the inode's * underlying buffer_head on success. If we pass 'inode' and it does not * have in-inode xattr, we have all inode data in memory that is needed * to recreate the on-disk version of this inode. */ static int __ext4_get_inode_loc(struct super_block *sb, unsigned long ino, struct inode *inode, struct ext4_iloc *iloc, ext4_fsblk_t *ret_block) { struct ext4_group_desc *gdp; struct buffer_head *bh; ext4_fsblk_t block; struct blk_plug plug; int inodes_per_block, inode_offset; iloc->bh = NULL; if (ino < EXT4_ROOT_INO || ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count)) return -EFSCORRUPTED; iloc->block_group = (ino - 1) / EXT4_INODES_PER_GROUP(sb); gdp = ext4_get_group_desc(sb, iloc->block_group, NULL); if (!gdp) return -EIO; /* * Figure out the offset within the block group inode table */ inodes_per_block = EXT4_SB(sb)->s_inodes_per_block; inode_offset = ((ino - 1) % EXT4_INODES_PER_GROUP(sb)); iloc->offset = (inode_offset % inodes_per_block) * EXT4_INODE_SIZE(sb); block = ext4_inode_table(sb, gdp); if ((block <= le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block)) || (block >= ext4_blocks_count(EXT4_SB(sb)->s_es))) { ext4_error(sb, "Invalid inode table block %llu in " "block_group %u", block, iloc->block_group); return -EFSCORRUPTED; } block += (inode_offset / inodes_per_block); bh = sb_getblk(sb, block); if (unlikely(!bh)) return -ENOMEM; if (ext4_buffer_uptodate(bh)) goto has_buffer; lock_buffer(bh); if (ext4_buffer_uptodate(bh)) { /* Someone brought it uptodate while we waited */ unlock_buffer(bh); goto has_buffer; } /* * If we have all information of the inode in memory and this * is the only valid inode in the block, we need not read the * block. */ if (inode && !ext4_test_inode_state(inode, EXT4_STATE_XATTR)) { struct buffer_head *bitmap_bh; int i, start; start = inode_offset & ~(inodes_per_block - 1); /* Is the inode bitmap in cache? */ bitmap_bh = sb_getblk(sb, ext4_inode_bitmap(sb, gdp)); if (unlikely(!bitmap_bh)) goto make_io; /* * If the inode bitmap isn't in cache then the * optimisation may end up performing two reads instead * of one, so skip it. */ if (!buffer_uptodate(bitmap_bh)) { brelse(bitmap_bh); goto make_io; } for (i = start; i < start + inodes_per_block; i++) { if (i == inode_offset) continue; if (ext4_test_bit(i, bitmap_bh->b_data)) break; } brelse(bitmap_bh); if (i == start + inodes_per_block) { struct ext4_inode *raw_inode = (struct ext4_inode *) (bh->b_data + iloc->offset); /* all other inodes are free, so skip I/O */ memset(bh->b_data, 0, bh->b_size); if (!ext4_test_inode_state(inode, EXT4_STATE_NEW)) ext4_fill_raw_inode(inode, raw_inode); set_buffer_uptodate(bh); unlock_buffer(bh); goto has_buffer; } } make_io: /* * If we need to do any I/O, try to pre-readahead extra * blocks from the inode table. */ blk_start_plug(&plug); if (EXT4_SB(sb)->s_inode_readahead_blks) { ext4_fsblk_t b, end, table; unsigned num; __u32 ra_blks = EXT4_SB(sb)->s_inode_readahead_blks; table = ext4_inode_table(sb, gdp); /* s_inode_readahead_blks is always a power of 2 */ b = block & ~((ext4_fsblk_t) ra_blks - 1); if (table > b) b = table; end = b + ra_blks; num = EXT4_INODES_PER_GROUP(sb); if (ext4_has_group_desc_csum(sb)) num -= ext4_itable_unused_count(sb, gdp); table += num / inodes_per_block; if (end > table) end = table; while (b <= end) ext4_sb_breadahead_unmovable(sb, b++); } /* * There are other valid inodes in the buffer, this inode * has in-inode xattrs, or we don't have this inode in memory. * Read the block from disk. */ trace_ext4_load_inode(sb, ino); ext4_read_bh_nowait(bh, REQ_META | REQ_PRIO, NULL); blk_finish_plug(&plug); wait_on_buffer(bh); ext4_simulate_fail_bh(sb, bh, EXT4_SIM_INODE_EIO); if (!buffer_uptodate(bh)) { if (ret_block) *ret_block = block; brelse(bh); return -EIO; } has_buffer: iloc->bh = bh; return 0; } static int __ext4_get_inode_loc_noinmem(struct inode *inode, struct ext4_iloc *iloc) { ext4_fsblk_t err_blk = 0; int ret; ret = __ext4_get_inode_loc(inode->i_sb, inode->i_ino, NULL, iloc, &err_blk); if (ret == -EIO) ext4_error_inode_block(inode, err_blk, EIO, "unable to read itable block"); return ret; } int ext4_get_inode_loc(struct inode *inode, struct ext4_iloc *iloc) { ext4_fsblk_t err_blk = 0; int ret; ret = __ext4_get_inode_loc(inode->i_sb, inode->i_ino, inode, iloc, &err_blk); if (ret == -EIO) ext4_error_inode_block(inode, err_blk, EIO, "unable to read itable block"); return ret; } int ext4_get_fc_inode_loc(struct super_block *sb, unsigned long ino, struct ext4_iloc *iloc) { return __ext4_get_inode_loc(sb, ino, NULL, iloc, NULL); } static bool ext4_should_enable_dax(struct inode *inode) { struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); if (test_opt2(inode->i_sb, DAX_NEVER)) return false; if (!S_ISREG(inode->i_mode)) return false; if (ext4_should_journal_data(inode)) return false; if (ext4_has_inline_data(inode)) return false; if (ext4_test_inode_flag(inode, EXT4_INODE_ENCRYPT)) return false; if (ext4_test_inode_flag(inode, EXT4_INODE_VERITY)) return false; if (!test_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags)) return false; if (test_opt(inode->i_sb, DAX_ALWAYS)) return true; return ext4_test_inode_flag(inode, EXT4_INODE_DAX); } void ext4_set_inode_flags(struct inode *inode, bool init) { unsigned int flags = EXT4_I(inode)->i_flags; unsigned int new_fl = 0; WARN_ON_ONCE(IS_DAX(inode) && init); if (flags & EXT4_SYNC_FL) new_fl |= S_SYNC; if (flags & EXT4_APPEND_FL) new_fl |= S_APPEND; if (flags & EXT4_IMMUTABLE_FL) new_fl |= S_IMMUTABLE; if (flags & EXT4_NOATIME_FL) new_fl |= S_NOATIME; if (flags & EXT4_DIRSYNC_FL) new_fl |= S_DIRSYNC; /* Because of the way inode_set_flags() works we must preserve S_DAX * here if already set. */ new_fl |= (inode->i_flags & S_DAX); if (init && ext4_should_enable_dax(inode)) new_fl |= S_DAX; if (flags & EXT4_ENCRYPT_FL) new_fl |= S_ENCRYPTED; if (flags & EXT4_CASEFOLD_FL) new_fl |= S_CASEFOLD; if (flags & EXT4_VERITY_FL) new_fl |= S_VERITY; inode_set_flags(inode, new_fl, S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC|S_DAX| S_ENCRYPTED|S_CASEFOLD|S_VERITY); } static blkcnt_t ext4_inode_blocks(struct ext4_inode *raw_inode, struct ext4_inode_info *ei) { blkcnt_t i_blocks ; struct inode *inode = &(ei->vfs_inode); struct super_block *sb = inode->i_sb; if (ext4_has_feature_huge_file(sb)) { /* we are using combined 48 bit field */ i_blocks = ((u64)le16_to_cpu(raw_inode->i_blocks_high)) << 32 | le32_to_cpu(raw_inode->i_blocks_lo); if (ext4_test_inode_flag(inode, EXT4_INODE_HUGE_FILE)) { /* i_blocks represent file system block size */ return i_blocks << (inode->i_blkbits - 9); } else { return i_blocks; } } else { return le32_to_cpu(raw_inode->i_blocks_lo); } } static inline int ext4_iget_extra_inode(struct inode *inode, struct ext4_inode *raw_inode, struct ext4_inode_info *ei) { __le32 *magic = (void *)raw_inode + EXT4_GOOD_OLD_INODE_SIZE + ei->i_extra_isize; if (EXT4_INODE_HAS_XATTR_SPACE(inode) && *magic == cpu_to_le32(EXT4_XATTR_MAGIC)) { int err; ext4_set_inode_state(inode, EXT4_STATE_XATTR); err = ext4_find_inline_data_nolock(inode); if (!err && ext4_has_inline_data(inode)) ext4_set_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA); return err; } else EXT4_I(inode)->i_inline_off = 0; return 0; } int ext4_get_projid(struct inode *inode, kprojid_t *projid) { if (!ext4_has_feature_project(inode->i_sb)) return -EOPNOTSUPP; *projid = EXT4_I(inode)->i_projid; return 0; } /* * ext4 has self-managed i_version for ea inodes, it stores the lower 32bit of * refcount in i_version, so use raw values if inode has EXT4_EA_INODE_FL flag * set. */ static inline void ext4_inode_set_iversion_queried(struct inode *inode, u64 val) { if (unlikely(EXT4_I(inode)->i_flags & EXT4_EA_INODE_FL)) inode_set_iversion_raw(inode, val); else inode_set_iversion_queried(inode, val); } static const char *check_igot_inode(struct inode *inode, ext4_iget_flags flags) { if (flags & EXT4_IGET_EA_INODE) { if (!(EXT4_I(inode)->i_flags & EXT4_EA_INODE_FL)) return "missing EA_INODE flag"; if (ext4_test_inode_state(inode, EXT4_STATE_XATTR) || EXT4_I(inode)->i_file_acl) return "ea_inode with extended attributes"; } else { if ((EXT4_I(inode)->i_flags & EXT4_EA_INODE_FL)) return "unexpected EA_INODE flag"; } if (is_bad_inode(inode) && !(flags & EXT4_IGET_BAD)) return "unexpected bad inode w/o EXT4_IGET_BAD"; return NULL; } struct inode *__ext4_iget(struct super_block *sb, unsigned long ino, ext4_iget_flags flags, const char *function, unsigned int line) { struct ext4_iloc iloc; struct ext4_inode *raw_inode; struct ext4_inode_info *ei; struct ext4_super_block *es = EXT4_SB(sb)->s_es; struct inode *inode; const char *err_str; journal_t *journal = EXT4_SB(sb)->s_journal; long ret; loff_t size; int block; uid_t i_uid; gid_t i_gid; projid_t i_projid; if ((!(flags & EXT4_IGET_SPECIAL) && ((ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO) || ino == le32_to_cpu(es->s_usr_quota_inum) || ino == le32_to_cpu(es->s_grp_quota_inum) || ino == le32_to_cpu(es->s_prj_quota_inum) || ino == le32_to_cpu(es->s_orphan_file_inum))) || (ino < EXT4_ROOT_INO) || (ino > le32_to_cpu(es->s_inodes_count))) { if (flags & EXT4_IGET_HANDLE) return ERR_PTR(-ESTALE); __ext4_error(sb, function, line, false, EFSCORRUPTED, 0, "inode #%lu: comm %s: iget: illegal inode #", ino, current->comm); return ERR_PTR(-EFSCORRUPTED); } inode = iget_locked(sb, ino); if (!inode) return ERR_PTR(-ENOMEM); if (!(inode->i_state & I_NEW)) { if ((err_str = check_igot_inode(inode, flags)) != NULL) { ext4_error_inode(inode, function, line, 0, err_str); iput(inode); return ERR_PTR(-EFSCORRUPTED); } return inode; } ei = EXT4_I(inode); iloc.bh = NULL; ret = __ext4_get_inode_loc_noinmem(inode, &iloc); if (ret < 0) goto bad_inode; raw_inode = ext4_raw_inode(&iloc); if ((flags & EXT4_IGET_HANDLE) && (raw_inode->i_links_count == 0) && (raw_inode->i_mode == 0)) { ret = -ESTALE; goto bad_inode; } if (EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE) { ei->i_extra_isize = le16_to_cpu(raw_inode->i_extra_isize); if (EXT4_GOOD_OLD_INODE_SIZE + ei->i_extra_isize > EXT4_INODE_SIZE(inode->i_sb) || (ei->i_extra_isize & 3)) { ext4_error_inode(inode, function, line, 0, "iget: bad extra_isize %u " "(inode size %u)", ei->i_extra_isize, EXT4_INODE_SIZE(inode->i_sb)); ret = -EFSCORRUPTED; goto bad_inode; } } else ei->i_extra_isize = 0; /* Precompute checksum seed for inode metadata */ if (ext4_has_metadata_csum(sb)) { struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); __u32 csum; __le32 inum = cpu_to_le32(inode->i_ino); __le32 gen = raw_inode->i_generation; csum = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&inum, sizeof(inum)); ei->i_csum_seed = ext4_chksum(sbi, csum, (__u8 *)&gen, sizeof(gen)); } if ((!ext4_inode_csum_verify(inode, raw_inode, ei) || ext4_simulate_fail(sb, EXT4_SIM_INODE_CRC)) && (!(EXT4_SB(sb)->s_mount_state & EXT4_FC_REPLAY))) { ext4_error_inode_err(inode, function, line, 0, EFSBADCRC, "iget: checksum invalid"); ret = -EFSBADCRC; goto bad_inode; } inode->i_mode = le16_to_cpu(raw_inode->i_mode); i_uid = (uid_t)le16_to_cpu(raw_inode->i_uid_low); i_gid = (gid_t)le16_to_cpu(raw_inode->i_gid_low); if (ext4_has_feature_project(sb) && EXT4_INODE_SIZE(sb) > EXT4_GOOD_OLD_INODE_SIZE && EXT4_FITS_IN_INODE(raw_inode, ei, i_projid)) i_projid = (projid_t)le32_to_cpu(raw_inode->i_projid); else i_projid = EXT4_DEF_PROJID; if (!(test_opt(inode->i_sb, NO_UID32))) { i_uid |= le16_to_cpu(raw_inode->i_uid_high) << 16; i_gid |= le16_to_cpu(raw_inode->i_gid_high) << 16; } i_uid_write(inode, i_uid); i_gid_write(inode, i_gid); ei->i_projid = make_kprojid(&init_user_ns, i_projid); set_nlink(inode, le16_to_cpu(raw_inode->i_links_count)); ext4_clear_state_flags(ei); /* Only relevant on 32-bit archs */ ei->i_inline_off = 0; ei->i_dir_start_lookup = 0; ei->i_dtime = le32_to_cpu(raw_inode->i_dtime); /* We now have enough fields to check if the inode was active or not. * This is needed because nfsd might try to access dead inodes * the test is that same one that e2fsck uses * NeilBrown 1999oct15 */ if (inode->i_nlink == 0) { if ((inode->i_mode == 0 || flags & EXT4_IGET_SPECIAL || !(EXT4_SB(inode->i_sb)->s_mount_state & EXT4_ORPHAN_FS)) && ino != EXT4_BOOT_LOADER_INO) { /* this inode is deleted or unallocated */ if (flags & EXT4_IGET_SPECIAL) { ext4_error_inode(inode, function, line, 0, "iget: special inode unallocated"); ret = -EFSCORRUPTED; } else ret = -ESTALE; goto bad_inode; } /* The only unlinked inodes we let through here have * valid i_mode and are being read by the orphan * recovery code: that's fine, we're about to complete * the process of deleting those. * OR it is the EXT4_BOOT_LOADER_INO which is * not initialized on a new filesystem. */ } ei->i_flags = le32_to_cpu(raw_inode->i_flags); ext4_set_inode_flags(inode, true); inode->i_blocks = ext4_inode_blocks(raw_inode, ei); ei->i_file_acl = le32_to_cpu(raw_inode->i_file_acl_lo); if (ext4_has_feature_64bit(sb)) ei->i_file_acl |= ((__u64)le16_to_cpu(raw_inode->i_file_acl_high)) << 32; inode->i_size = ext4_isize(sb, raw_inode); if ((size = i_size_read(inode)) < 0) { ext4_error_inode(inode, function, line, 0, "iget: bad i_size value: %lld", size); ret = -EFSCORRUPTED; goto bad_inode; } /* * If dir_index is not enabled but there's dir with INDEX flag set, * we'd normally treat htree data as empty space. But with metadata * checksumming that corrupts checksums so forbid that. */ if (!ext4_has_feature_dir_index(sb) && ext4_has_metadata_csum(sb) && ext4_test_inode_flag(inode, EXT4_INODE_INDEX)) { ext4_error_inode(inode, function, line, 0, "iget: Dir with htree data on filesystem without dir_index feature."); ret = -EFSCORRUPTED; goto bad_inode; } ei->i_disksize = inode->i_size; #ifdef CONFIG_QUOTA ei->i_reserved_quota = 0; #endif inode->i_generation = le32_to_cpu(raw_inode->i_generation); ei->i_block_group = iloc.block_group; ei->i_last_alloc_group = ~0; /* * NOTE! The in-memory inode i_data array is in little-endian order * even on big-endian machines: we do NOT byteswap the block numbers! */ for (block = 0; block < EXT4_N_BLOCKS; block++) ei->i_data[block] = raw_inode->i_block[block]; INIT_LIST_HEAD(&ei->i_orphan); ext4_fc_init_inode(&ei->vfs_inode); /* * Set transaction id's of transactions that have to be committed * to finish f[data]sync. We set them to currently running transaction * as we cannot be sure that the inode or some of its metadata isn't * part of the transaction - the inode could have been reclaimed and * now it is reread from disk. */ if (journal) { transaction_t *transaction; tid_t tid; read_lock(&journal->j_state_lock); if (journal->j_running_transaction) transaction = journal->j_running_transaction; else transaction = journal->j_committing_transaction; if (transaction) tid = transaction->t_tid; else tid = journal->j_commit_sequence; read_unlock(&journal->j_state_lock); ei->i_sync_tid = tid; ei->i_datasync_tid = tid; } if (EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE) { if (ei->i_extra_isize == 0) { /* The extra space is currently unused. Use it. */ BUILD_BUG_ON(sizeof(struct ext4_inode) & 3); ei->i_extra_isize = sizeof(struct ext4_inode) - EXT4_GOOD_OLD_INODE_SIZE; } else { ret = ext4_iget_extra_inode(inode, raw_inode, ei); if (ret) goto bad_inode; } } EXT4_INODE_GET_CTIME(inode, raw_inode); EXT4_INODE_GET_ATIME(inode, raw_inode); EXT4_INODE_GET_MTIME(inode, raw_inode); EXT4_EINODE_GET_XTIME(i_crtime, ei, raw_inode); if (likely(!test_opt2(inode->i_sb, HURD_COMPAT))) { u64 ivers = le32_to_cpu(raw_inode->i_disk_version); if (EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE) { if (EXT4_FITS_IN_INODE(raw_inode, ei, i_version_hi)) ivers |= (__u64)(le32_to_cpu(raw_inode->i_version_hi)) << 32; } ext4_inode_set_iversion_queried(inode, ivers); } ret = 0; if (ei->i_file_acl && !ext4_inode_block_valid(inode, ei->i_file_acl, 1)) { ext4_error_inode(inode, function, line, 0, "iget: bad extended attribute block %llu", ei->i_file_acl); ret = -EFSCORRUPTED; goto bad_inode; } else if (!ext4_has_inline_data(inode)) { /* validate the block references in the inode */ if (!(EXT4_SB(sb)->s_mount_state & EXT4_FC_REPLAY) && (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || (S_ISLNK(inode->i_mode) && !ext4_inode_is_fast_symlink(inode)))) { if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) ret = ext4_ext_check_inode(inode); else ret = ext4_ind_check_inode(inode); } } if (ret) goto bad_inode; if (S_ISREG(inode->i_mode)) { inode->i_op = &ext4_file_inode_operations; inode->i_fop = &ext4_file_operations; ext4_set_aops(inode); } else if (S_ISDIR(inode->i_mode)) { inode->i_op = &ext4_dir_inode_operations; inode->i_fop = &ext4_dir_operations; } else if (S_ISLNK(inode->i_mode)) { /* VFS does not allow setting these so must be corruption */ if (IS_APPEND(inode) || IS_IMMUTABLE(inode)) { ext4_error_inode(inode, function, line, 0, "iget: immutable or append flags " "not allowed on symlinks"); ret = -EFSCORRUPTED; goto bad_inode; } if (IS_ENCRYPTED(inode)) { inode->i_op = &ext4_encrypted_symlink_inode_operations; } else if (ext4_inode_is_fast_symlink(inode)) { inode->i_link = (char *)ei->i_data; inode->i_op = &ext4_fast_symlink_inode_operations; nd_terminate_link(ei->i_data, inode->i_size, sizeof(ei->i_data) - 1); } else { inode->i_op = &ext4_symlink_inode_operations; } } else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode) || S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) { inode->i_op = &ext4_special_inode_operations; if (raw_inode->i_block[0]) init_special_inode(inode, inode->i_mode, old_decode_dev(le32_to_cpu(raw_inode->i_block[0]))); else init_special_inode(inode, inode->i_mode, new_decode_dev(le32_to_cpu(raw_inode->i_block[1]))); } else if (ino == EXT4_BOOT_LOADER_INO) { make_bad_inode(inode); } else { ret = -EFSCORRUPTED; ext4_error_inode(inode, function, line, 0, "iget: bogus i_mode (%o)", inode->i_mode); goto bad_inode; } if (IS_CASEFOLDED(inode) && !ext4_has_feature_casefold(inode->i_sb)) { ext4_error_inode(inode, function, line, 0, "casefold flag without casefold feature"); ret = -EFSCORRUPTED; goto bad_inode; } if ((err_str = check_igot_inode(inode, flags)) != NULL) { ext4_error_inode(inode, function, line, 0, err_str); ret = -EFSCORRUPTED; goto bad_inode; } brelse(iloc.bh); unlock_new_inode(inode); return inode; bad_inode: brelse(iloc.bh); iget_failed(inode); return ERR_PTR(ret); } static void __ext4_update_other_inode_time(struct super_block *sb, unsigned long orig_ino, unsigned long ino, struct ext4_inode *raw_inode) { struct inode *inode; inode = find_inode_by_ino_rcu(sb, ino); if (!inode) return; if (!inode_is_dirtytime_only(inode)) return; spin_lock(&inode->i_lock); if (inode_is_dirtytime_only(inode)) { struct ext4_inode_info *ei = EXT4_I(inode); inode->i_state &= ~I_DIRTY_TIME; spin_unlock(&inode->i_lock); spin_lock(&ei->i_raw_lock); EXT4_INODE_SET_CTIME(inode, raw_inode); EXT4_INODE_SET_MTIME(inode, raw_inode); EXT4_INODE_SET_ATIME(inode, raw_inode); ext4_inode_csum_set(inode, raw_inode, ei); spin_unlock(&ei->i_raw_lock); trace_ext4_other_inode_update_time(inode, orig_ino); return; } spin_unlock(&inode->i_lock); } /* * Opportunistically update the other time fields for other inodes in * the same inode table block. */ static void ext4_update_other_inodes_time(struct super_block *sb, unsigned long orig_ino, char *buf) { unsigned long ino; int i, inodes_per_block = EXT4_SB(sb)->s_inodes_per_block; int inode_size = EXT4_INODE_SIZE(sb); /* * Calculate the first inode in the inode table block. Inode * numbers are one-based. That is, the first inode in a block * (assuming 4k blocks and 256 byte inodes) is (n*16 + 1). */ ino = ((orig_ino - 1) & ~(inodes_per_block - 1)) + 1; rcu_read_lock(); for (i = 0; i < inodes_per_block; i++, ino++, buf += inode_size) { if (ino == orig_ino) continue; __ext4_update_other_inode_time(sb, orig_ino, ino, (struct ext4_inode *)buf); } rcu_read_unlock(); } /* * Post the struct inode info into an on-disk inode location in the * buffer-cache. This gobbles the caller's reference to the * buffer_head in the inode location struct. * * The caller must have write access to iloc->bh. */ static int ext4_do_update_inode(handle_t *handle, struct inode *inode, struct ext4_iloc *iloc) { struct ext4_inode *raw_inode = ext4_raw_inode(iloc); struct ext4_inode_info *ei = EXT4_I(inode); struct buffer_head *bh = iloc->bh; struct super_block *sb = inode->i_sb; int err; int need_datasync = 0, set_large_file = 0; spin_lock(&ei->i_raw_lock); /* * For fields not tracked in the in-memory inode, initialise them * to zero for new inodes. */ if (ext4_test_inode_state(inode, EXT4_STATE_NEW)) memset(raw_inode, 0, EXT4_SB(inode->i_sb)->s_inode_size); if (READ_ONCE(ei->i_disksize) != ext4_isize(inode->i_sb, raw_inode)) need_datasync = 1; if (ei->i_disksize > 0x7fffffffULL) { if (!ext4_has_feature_large_file(sb) || EXT4_SB(sb)->s_es->s_rev_level == cpu_to_le32(EXT4_GOOD_OLD_REV)) set_large_file = 1; } err = ext4_fill_raw_inode(inode, raw_inode); spin_unlock(&ei->i_raw_lock); if (err) { EXT4_ERROR_INODE(inode, "corrupted inode contents"); goto out_brelse; } if (inode->i_sb->s_flags & SB_LAZYTIME) ext4_update_other_inodes_time(inode->i_sb, inode->i_ino, bh->b_data); BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata"); err = ext4_handle_dirty_metadata(handle, NULL, bh); if (err) goto out_error; ext4_clear_inode_state(inode, EXT4_STATE_NEW); if (set_large_file) { BUFFER_TRACE(EXT4_SB(sb)->s_sbh, "get write access"); err = ext4_journal_get_write_access(handle, sb, EXT4_SB(sb)->s_sbh, EXT4_JTR_NONE); if (err) goto out_error; lock_buffer(EXT4_SB(sb)->s_sbh); ext4_set_feature_large_file(sb); ext4_superblock_csum_set(sb); unlock_buffer(EXT4_SB(sb)->s_sbh); ext4_handle_sync(handle); err = ext4_handle_dirty_metadata(handle, NULL, EXT4_SB(sb)->s_sbh); } ext4_update_inode_fsync_trans(handle, inode, need_datasync); out_error: ext4_std_error(inode->i_sb, err); out_brelse: brelse(bh); return err; } /* * ext4_write_inode() * * We are called from a few places: * * - Within generic_file_aio_write() -> generic_write_sync() for O_SYNC files. * Here, there will be no transaction running. We wait for any running * transaction to commit. * * - Within flush work (sys_sync(), kupdate and such). * We wait on commit, if told to. * * - Within iput_final() -> write_inode_now() * We wait on commit, if told to. * * In all cases it is actually safe for us to return without doing anything, * because the inode has been copied into a raw inode buffer in * ext4_mark_inode_dirty(). This is a correctness thing for WB_SYNC_ALL * writeback. * * Note that we are absolutely dependent upon all inode dirtiers doing the * right thing: they *must* call mark_inode_dirty() after dirtying info in * which we are interested. * * It would be a bug for them to not do this. The code: * * mark_inode_dirty(inode) * stuff(); * inode->i_size = expr; * * is in error because write_inode() could occur while `stuff()' is running, * and the new i_size will be lost. Plus the inode will no longer be on the * superblock's dirty inode list. */ int ext4_write_inode(struct inode *inode, struct writeback_control *wbc) { int err; if (WARN_ON_ONCE(current->flags & PF_MEMALLOC)) return 0; if (unlikely(ext4_forced_shutdown(inode->i_sb))) return -EIO; if (EXT4_SB(inode->i_sb)->s_journal) { if (ext4_journal_current_handle()) { ext4_debug("called recursively, non-PF_MEMALLOC!\n"); dump_stack(); return -EIO; } /* * No need to force transaction in WB_SYNC_NONE mode. Also * ext4_sync_fs() will force the commit after everything is * written. */ if (wbc->sync_mode != WB_SYNC_ALL || wbc->for_sync) return 0; err = ext4_fc_commit(EXT4_SB(inode->i_sb)->s_journal, EXT4_I(inode)->i_sync_tid); } else { struct ext4_iloc iloc; err = __ext4_get_inode_loc_noinmem(inode, &iloc); if (err) return err; /* * sync(2) will flush the whole buffer cache. No need to do * it here separately for each inode. */ if (wbc->sync_mode == WB_SYNC_ALL && !wbc->for_sync) sync_dirty_buffer(iloc.bh); if (buffer_req(iloc.bh) && !buffer_uptodate(iloc.bh)) { ext4_error_inode_block(inode, iloc.bh->b_blocknr, EIO, "IO error syncing inode"); err = -EIO; } brelse(iloc.bh); } return err; } /* * In data=journal mode ext4_journalled_invalidate_folio() may fail to invalidate * buffers that are attached to a folio straddling i_size and are undergoing * commit. In that case we have to wait for commit to finish and try again. */ static void ext4_wait_for_tail_page_commit(struct inode *inode) { unsigned offset; journal_t *journal = EXT4_SB(inode->i_sb)->s_journal; tid_t commit_tid = 0; int ret; offset = inode->i_size & (PAGE_SIZE - 1); /* * If the folio is fully truncated, we don't need to wait for any commit * (and we even should not as __ext4_journalled_invalidate_folio() may * strip all buffers from the folio but keep the folio dirty which can then * confuse e.g. concurrent ext4_writepages() seeing dirty folio without * buffers). Also we don't need to wait for any commit if all buffers in * the folio remain valid. This is most beneficial for the common case of * blocksize == PAGESIZE. */ if (!offset || offset > (PAGE_SIZE - i_blocksize(inode))) return; while (1) { struct folio *folio = filemap_lock_folio(inode->i_mapping, inode->i_size >> PAGE_SHIFT); if (IS_ERR(folio)) return; ret = __ext4_journalled_invalidate_folio(folio, offset, folio_size(folio) - offset); folio_unlock(folio); folio_put(folio); if (ret != -EBUSY) return; commit_tid = 0; read_lock(&journal->j_state_lock); if (journal->j_committing_transaction) commit_tid = journal->j_committing_transaction->t_tid; read_unlock(&journal->j_state_lock); if (commit_tid) jbd2_log_wait_commit(journal, commit_tid); } } /* * ext4_setattr() * * Called from notify_change. * * We want to trap VFS attempts to truncate the file as soon as * possible. In particular, we want to make sure that when the VFS * shrinks i_size, we put the inode on the orphan list and modify * i_disksize immediately, so that during the subsequent flushing of * dirty pages and freeing of disk blocks, we can guarantee that any * commit will leave the blocks being flushed in an unused state on * disk. (On recovery, the inode will get truncated and the blocks will * be freed, so we have a strong guarantee that no future commit will * leave these blocks visible to the user.) * * Another thing we have to assure is that if we are in ordered mode * and inode is still attached to the committing transaction, we must * we start writeout of all the dirty pages which are being truncated. * This way we are sure that all the data written in the previous * transaction are already on disk (truncate waits for pages under * writeback). * * Called with inode->i_rwsem down. */ int ext4_setattr(struct mnt_idmap *idmap, struct dentry *dentry, struct iattr *attr) { struct inode *inode = d_inode(dentry); int error, rc = 0; int orphan = 0; const unsigned int ia_valid = attr->ia_valid; bool inc_ivers = true; if (unlikely(ext4_forced_shutdown(inode->i_sb))) return -EIO; if (unlikely(IS_IMMUTABLE(inode))) return -EPERM; if (unlikely(IS_APPEND(inode) && (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | ATTR_TIMES_SET)))) return -EPERM; error = setattr_prepare(idmap, dentry, attr); if (error) return error; error = fscrypt_prepare_setattr(dentry, attr); if (error) return error; error = fsverity_prepare_setattr(dentry, attr); if (error) return error; if (is_quota_modification(idmap, inode, attr)) { error = dquot_initialize(inode); if (error) return error; } if (i_uid_needs_update(idmap, attr, inode) || i_gid_needs_update(idmap, attr, inode)) { handle_t *handle; /* (user+group)*(old+new) structure, inode write (sb, * inode block, ? - but truncate inode update has it) */ handle = ext4_journal_start(inode, EXT4_HT_QUOTA, (EXT4_MAXQUOTAS_INIT_BLOCKS(inode->i_sb) + EXT4_MAXQUOTAS_DEL_BLOCKS(inode->i_sb)) + 3); if (IS_ERR(handle)) { error = PTR_ERR(handle); goto err_out; } /* dquot_transfer() calls back ext4_get_inode_usage() which * counts xattr inode references. */ down_read(&EXT4_I(inode)->xattr_sem); error = dquot_transfer(idmap, inode, attr); up_read(&EXT4_I(inode)->xattr_sem); if (error) { ext4_journal_stop(handle); return error; } /* Update corresponding info in inode so that everything is in * one transaction */ i_uid_update(idmap, attr, inode); i_gid_update(idmap, attr, inode); error = ext4_mark_inode_dirty(handle, inode); ext4_journal_stop(handle); if (unlikely(error)) { return error; } } if (attr->ia_valid & ATTR_SIZE) { handle_t *handle; loff_t oldsize = inode->i_size; loff_t old_disksize; int shrink = (attr->ia_size < inode->i_size); if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) { struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); if (attr->ia_size > sbi->s_bitmap_maxbytes) { return -EFBIG; } } if (!S_ISREG(inode->i_mode)) { return -EINVAL; } if (attr->ia_size == inode->i_size) inc_ivers = false; if (shrink) { if (ext4_should_order_data(inode)) { error = ext4_begin_ordered_truncate(inode, attr->ia_size); if (error) goto err_out; } /* * Blocks are going to be removed from the inode. Wait * for dio in flight. */ inode_dio_wait(inode); } filemap_invalidate_lock(inode->i_mapping); rc = ext4_break_layouts(inode); if (rc) { filemap_invalidate_unlock(inode->i_mapping); goto err_out; } if (attr->ia_size != inode->i_size) { handle = ext4_journal_start(inode, EXT4_HT_INODE, 3); if (IS_ERR(handle)) { error = PTR_ERR(handle); goto out_mmap_sem; } if (ext4_handle_valid(handle) && shrink) { error = ext4_orphan_add(handle, inode); orphan = 1; } /* * Update c/mtime on truncate up, ext4_truncate() will * update c/mtime in shrink case below */ if (!shrink) inode_set_mtime_to_ts(inode, inode_set_ctime_current(inode)); if (shrink) ext4_fc_track_range(handle, inode, (attr->ia_size > 0 ? attr->ia_size - 1 : 0) >> inode->i_sb->s_blocksize_bits, EXT_MAX_BLOCKS - 1); else ext4_fc_track_range( handle, inode, (oldsize > 0 ? oldsize - 1 : oldsize) >> inode->i_sb->s_blocksize_bits, (attr->ia_size > 0 ? attr->ia_size - 1 : 0) >> inode->i_sb->s_blocksize_bits); down_write(&EXT4_I(inode)->i_data_sem); old_disksize = EXT4_I(inode)->i_disksize; EXT4_I(inode)->i_disksize = attr->ia_size; rc = ext4_mark_inode_dirty(handle, inode); if (!error) error = rc; /* * We have to update i_size under i_data_sem together * with i_disksize to avoid races with writeback code * running ext4_wb_update_i_disksize(). */ if (!error) i_size_write(inode, attr->ia_size); else EXT4_I(inode)->i_disksize = old_disksize; up_write(&EXT4_I(inode)->i_data_sem); ext4_journal_stop(handle); if (error) goto out_mmap_sem; if (!shrink) { pagecache_isize_extended(inode, oldsize, inode->i_size); } else if (ext4_should_journal_data(inode)) { ext4_wait_for_tail_page_commit(inode); } } /* * Truncate pagecache after we've waited for commit * in data=journal mode to make pages freeable. */ truncate_pagecache(inode, inode->i_size); /* * Call ext4_truncate() even if i_size didn't change to * truncate possible preallocated blocks. */ if (attr->ia_size <= oldsize) { rc = ext4_truncate(inode); if (rc) error = rc; } out_mmap_sem: filemap_invalidate_unlock(inode->i_mapping); } if (!error) { if (inc_ivers) inode_inc_iversion(inode); setattr_copy(idmap, inode, attr); mark_inode_dirty(inode); } /* * If the call to ext4_truncate failed to get a transaction handle at * all, we need to clean up the in-core orphan list manually. */ if (orphan && inode->i_nlink) ext4_orphan_del(NULL, inode); if (!error && (ia_valid & ATTR_MODE)) rc = posix_acl_chmod(idmap, dentry, inode->i_mode); err_out: if (error) ext4_std_error(inode->i_sb, error); if (!error) error = rc; return error; } u32 ext4_dio_alignment(struct inode *inode) { if (fsverity_active(inode)) return 0; if (ext4_should_journal_data(inode)) return 0; if (ext4_has_inline_data(inode)) return 0; if (IS_ENCRYPTED(inode)) { if (!fscrypt_dio_supported(inode)) return 0; return i_blocksize(inode); } return 1; /* use the iomap defaults */ } int ext4_getattr(struct mnt_idmap *idmap, const struct path *path, struct kstat *stat, u32 request_mask, unsigned int query_flags) { struct inode *inode = d_inode(path->dentry); struct ext4_inode *raw_inode; struct ext4_inode_info *ei = EXT4_I(inode); unsigned int flags; if ((request_mask & STATX_BTIME) && EXT4_FITS_IN_INODE(raw_inode, ei, i_crtime)) { stat->result_mask |= STATX_BTIME; stat->btime.tv_sec = ei->i_crtime.tv_sec; stat->btime.tv_nsec = ei->i_crtime.tv_nsec; } /* * Return the DIO alignment restrictions if requested. We only return * this information when requested, since on encrypted files it might * take a fair bit of work to get if the file wasn't opened recently. */ if ((request_mask & STATX_DIOALIGN) && S_ISREG(inode->i_mode)) { u32 dio_align = ext4_dio_alignment(inode); stat->result_mask |= STATX_DIOALIGN; if (dio_align == 1) { struct block_device *bdev = inode->i_sb->s_bdev; /* iomap defaults */ stat->dio_mem_align = bdev_dma_alignment(bdev) + 1; stat->dio_offset_align = bdev_logical_block_size(bdev); } else { stat->dio_mem_align = dio_align; stat->dio_offset_align = dio_align; } } flags = ei->i_flags & EXT4_FL_USER_VISIBLE; if (flags & EXT4_APPEND_FL) stat->attributes |= STATX_ATTR_APPEND; if (flags & EXT4_COMPR_FL) stat->attributes |= STATX_ATTR_COMPRESSED; if (flags & EXT4_ENCRYPT_FL) stat->attributes |= STATX_ATTR_ENCRYPTED; if (flags & EXT4_IMMUTABLE_FL) stat->attributes |= STATX_ATTR_IMMUTABLE; if (flags & EXT4_NODUMP_FL) stat->attributes |= STATX_ATTR_NODUMP; if (flags & EXT4_VERITY_FL) stat->attributes |= STATX_ATTR_VERITY; stat->attributes_mask |= (STATX_ATTR_APPEND | STATX_ATTR_COMPRESSED | STATX_ATTR_ENCRYPTED | STATX_ATTR_IMMUTABLE | STATX_ATTR_NODUMP | STATX_ATTR_VERITY); generic_fillattr(idmap, request_mask, inode, stat); return 0; } int ext4_file_getattr(struct mnt_idmap *idmap, const struct path *path, struct kstat *stat, u32 request_mask, unsigned int query_flags) { struct inode *inode = d_inode(path->dentry); u64 delalloc_blocks; ext4_getattr(idmap, path, stat, request_mask, query_flags); /* * If there is inline data in the inode, the inode will normally not * have data blocks allocated (it may have an external xattr block). * Report at least one sector for such files, so tools like tar, rsync, * others don't incorrectly think the file is completely sparse. */ if (unlikely(ext4_has_inline_data(inode))) stat->blocks += (stat->size + 511) >> 9; /* * We can't update i_blocks if the block allocation is delayed * otherwise in the case of system crash before the real block * allocation is done, we will have i_blocks inconsistent with * on-disk file blocks. * We always keep i_blocks updated together with real * allocation. But to not confuse with user, stat * will return the blocks that include the delayed allocation * blocks for this file. */ delalloc_blocks = EXT4_C2B(EXT4_SB(inode->i_sb), EXT4_I(inode)->i_reserved_data_blocks); stat->blocks += delalloc_blocks << (inode->i_sb->s_blocksize_bits - 9); return 0; } static int ext4_index_trans_blocks(struct inode *inode, int lblocks, int pextents) { if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) return ext4_ind_trans_blocks(inode, lblocks); return ext4_ext_index_trans_blocks(inode, pextents); } /* * Account for index blocks, block groups bitmaps and block group * descriptor blocks if modify datablocks and index blocks * worse case, the indexs blocks spread over different block groups * * If datablocks are discontiguous, they are possible to spread over * different block groups too. If they are contiguous, with flexbg, * they could still across block group boundary. * * Also account for superblock, inode, quota and xattr blocks */ static int ext4_meta_trans_blocks(struct inode *inode, int lblocks, int pextents) { ext4_group_t groups, ngroups = ext4_get_groups_count(inode->i_sb); int gdpblocks; int idxblocks; int ret; /* * How many index blocks need to touch to map @lblocks logical blocks * to @pextents physical extents? */ idxblocks = ext4_index_trans_blocks(inode, lblocks, pextents); ret = idxblocks; /* * Now let's see how many group bitmaps and group descriptors need * to account */ groups = idxblocks + pextents; gdpblocks = groups; if (groups > ngroups) groups = ngroups; if (groups > EXT4_SB(inode->i_sb)->s_gdb_count) gdpblocks = EXT4_SB(inode->i_sb)->s_gdb_count; /* bitmaps and block group descriptor blocks */ ret += groups + gdpblocks; /* Blocks for super block, inode, quota and xattr blocks */ ret += EXT4_META_TRANS_BLOCKS(inode->i_sb); return ret; } /* * Calculate the total number of credits to reserve to fit * the modification of a single pages into a single transaction, * which may include multiple chunks of block allocations. * * This could be called via ext4_write_begin() * * We need to consider the worse case, when * one new block per extent. */ int ext4_writepage_trans_blocks(struct inode *inode) { int bpp = ext4_journal_blocks_per_page(inode); int ret; ret = ext4_meta_trans_blocks(inode, bpp, bpp); /* Account for data blocks for journalled mode */ if (ext4_should_journal_data(inode)) ret += bpp; return ret; } /* * Calculate the journal credits for a chunk of data modification. * * This is called from DIO, fallocate or whoever calling * ext4_map_blocks() to map/allocate a chunk of contiguous disk blocks. * * journal buffers for data blocks are not included here, as DIO * and fallocate do no need to journal data buffers. */ int ext4_chunk_trans_blocks(struct inode *inode, int nrblocks) { return ext4_meta_trans_blocks(inode, nrblocks, 1); } /* * The caller must have previously called ext4_reserve_inode_write(). * Give this, we know that the caller already has write access to iloc->bh. */ int ext4_mark_iloc_dirty(handle_t *handle, struct inode *inode, struct ext4_iloc *iloc) { int err = 0; if (unlikely(ext4_forced_shutdown(inode->i_sb))) { put_bh(iloc->bh); return -EIO; } ext4_fc_track_inode(handle, inode); /* the do_update_inode consumes one bh->b_count */ get_bh(iloc->bh); /* ext4_do_update_inode() does jbd2_journal_dirty_metadata */ err = ext4_do_update_inode(handle, inode, iloc); put_bh(iloc->bh); return err; } /* * On success, We end up with an outstanding reference count against * iloc->bh. This _must_ be cleaned up later. */ int ext4_reserve_inode_write(handle_t *handle, struct inode *inode, struct ext4_iloc *iloc) { int err; if (unlikely(ext4_forced_shutdown(inode->i_sb))) return -EIO; err = ext4_get_inode_loc(inode, iloc); if (!err) { BUFFER_TRACE(iloc->bh, "get_write_access"); err = ext4_journal_get_write_access(handle, inode->i_sb, iloc->bh, EXT4_JTR_NONE); if (err) { brelse(iloc->bh); iloc->bh = NULL; } } ext4_std_error(inode->i_sb, err); return err; } static int __ext4_expand_extra_isize(struct inode *inode, unsigned int new_extra_isize, struct ext4_iloc *iloc, handle_t *handle, int *no_expand) { struct ext4_inode *raw_inode; struct ext4_xattr_ibody_header *header; unsigned int inode_size = EXT4_INODE_SIZE(inode->i_sb); struct ext4_inode_info *ei = EXT4_I(inode); int error; /* this was checked at iget time, but double check for good measure */ if ((EXT4_GOOD_OLD_INODE_SIZE + ei->i_extra_isize > inode_size) || (ei->i_extra_isize & 3)) { EXT4_ERROR_INODE(inode, "bad extra_isize %u (inode size %u)", ei->i_extra_isize, EXT4_INODE_SIZE(inode->i_sb)); return -EFSCORRUPTED; } if ((new_extra_isize < ei->i_extra_isize) || (new_extra_isize < 4) || (new_extra_isize > inode_size - EXT4_GOOD_OLD_INODE_SIZE)) return -EINVAL; /* Should never happen */ raw_inode = ext4_raw_inode(iloc); header = IHDR(inode, raw_inode); /* No extended attributes present */ if (!ext4_test_inode_state(inode, EXT4_STATE_XATTR) || header->h_magic != cpu_to_le32(EXT4_XATTR_MAGIC)) { memset((void *)raw_inode + EXT4_GOOD_OLD_INODE_SIZE + EXT4_I(inode)->i_extra_isize, 0, new_extra_isize - EXT4_I(inode)->i_extra_isize); EXT4_I(inode)->i_extra_isize = new_extra_isize; return 0; } /* * We may need to allocate external xattr block so we need quotas * initialized. Here we can be called with various locks held so we * cannot affort to initialize quotas ourselves. So just bail. */ if (dquot_initialize_needed(inode)) return -EAGAIN; /* try to expand with EAs present */ error = ext4_expand_extra_isize_ea(inode, new_extra_isize, raw_inode, handle); if (error) { /* * Inode size expansion failed; don't try again */ *no_expand = 1; } return error; } /* * Expand an inode by new_extra_isize bytes. * Returns 0 on success or negative error number on failure. */ static int ext4_try_to_expand_extra_isize(struct inode *inode, unsigned int new_extra_isize, struct ext4_iloc iloc, handle_t *handle) { int no_expand; int error; if (ext4_test_inode_state(inode, EXT4_STATE_NO_EXPAND)) return -EOVERFLOW; /* * In nojournal mode, we can immediately attempt to expand * the inode. When journaled, we first need to obtain extra * buffer credits since we may write into the EA block * with this same handle. If journal_extend fails, then it will * only result in a minor loss of functionality for that inode. * If this is felt to be critical, then e2fsck should be run to * force a large enough s_min_extra_isize. */ if (ext4_journal_extend(handle, EXT4_DATA_TRANS_BLOCKS(inode->i_sb), 0) != 0) return -ENOSPC; if (ext4_write_trylock_xattr(inode, &no_expand) == 0) return -EBUSY; error = __ext4_expand_extra_isize(inode, new_extra_isize, &iloc, handle, &no_expand); ext4_write_unlock_xattr(inode, &no_expand); return error; } int ext4_expand_extra_isize(struct inode *inode, unsigned int new_extra_isize, struct ext4_iloc *iloc) { handle_t *handle; int no_expand; int error, rc; if (ext4_test_inode_state(inode, EXT4_STATE_NO_EXPAND)) { brelse(iloc->bh); return -EOVERFLOW; } handle = ext4_journal_start(inode, EXT4_HT_INODE, EXT4_DATA_TRANS_BLOCKS(inode->i_sb)); if (IS_ERR(handle)) { error = PTR_ERR(handle); brelse(iloc->bh); return error; } ext4_write_lock_xattr(inode, &no_expand); BUFFER_TRACE(iloc->bh, "get_write_access"); error = ext4_journal_get_write_access(handle, inode->i_sb, iloc->bh, EXT4_JTR_NONE); if (error) { brelse(iloc->bh); goto out_unlock; } error = __ext4_expand_extra_isize(inode, new_extra_isize, iloc, handle, &no_expand); rc = ext4_mark_iloc_dirty(handle, inode, iloc); if (!error) error = rc; out_unlock: ext4_write_unlock_xattr(inode, &no_expand); ext4_journal_stop(handle); return error; } /* * What we do here is to mark the in-core inode as clean with respect to inode * dirtiness (it may still be data-dirty). * This means that the in-core inode may be reaped by prune_icache * without having to perform any I/O. This is a very good thing, * because *any* task may call prune_icache - even ones which * have a transaction open against a different journal. * * Is this cheating? Not really. Sure, we haven't written the * inode out, but prune_icache isn't a user-visible syncing function. * Whenever the user wants stuff synced (sys_sync, sys_msync, sys_fsync) * we start and wait on commits. */ int __ext4_mark_inode_dirty(handle_t *handle, struct inode *inode, const char *func, unsigned int line) { struct ext4_iloc iloc; struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); int err; might_sleep(); trace_ext4_mark_inode_dirty(inode, _RET_IP_); err = ext4_reserve_inode_write(handle, inode, &iloc); if (err) goto out; if (EXT4_I(inode)->i_extra_isize < sbi->s_want_extra_isize) ext4_try_to_expand_extra_isize(inode, sbi->s_want_extra_isize, iloc, handle); err = ext4_mark_iloc_dirty(handle, inode, &iloc); out: if (unlikely(err)) ext4_error_inode_err(inode, func, line, 0, err, "mark_inode_dirty error"); return err; } /* * ext4_dirty_inode() is called from __mark_inode_dirty() * * We're really interested in the case where a file is being extended. * i_size has been changed by generic_commit_write() and we thus need * to include the updated inode in the current transaction. * * Also, dquot_alloc_block() will always dirty the inode when blocks * are allocated to the file. * * If the inode is marked synchronous, we don't honour that here - doing * so would cause a commit on atime updates, which we don't bother doing. * We handle synchronous inodes at the highest possible level. */ void ext4_dirty_inode(struct inode *inode, int flags) { handle_t *handle; handle = ext4_journal_start(inode, EXT4_HT_INODE, 2); if (IS_ERR(handle)) return; ext4_mark_inode_dirty(handle, inode); ext4_journal_stop(handle); } int ext4_change_inode_journal_flag(struct inode *inode, int val) { journal_t *journal; handle_t *handle; int err; int alloc_ctx; /* * We have to be very careful here: changing a data block's * journaling status dynamically is dangerous. If we write a * data block to the journal, change the status and then delete * that block, we risk forgetting to revoke the old log record * from the journal and so a subsequent replay can corrupt data. * So, first we make sure that the journal is empty and that * nobody is changing anything. */ journal = EXT4_JOURNAL(inode); if (!journal) return 0; if (is_journal_aborted(journal)) return -EROFS; /* Wait for all existing dio workers */ inode_dio_wait(inode); /* * Before flushing the journal and switching inode's aops, we have * to flush all dirty data the inode has. There can be outstanding * delayed allocations, there can be unwritten extents created by * fallocate or buffered writes in dioread_nolock mode covered by * dirty data which can be converted only after flushing the dirty * data (and journalled aops don't know how to handle these cases). */ if (val) { filemap_invalidate_lock(inode->i_mapping); err = filemap_write_and_wait(inode->i_mapping); if (err < 0) { filemap_invalidate_unlock(inode->i_mapping); return err; } } alloc_ctx = ext4_writepages_down_write(inode->i_sb); jbd2_journal_lock_updates(journal); /* * OK, there are no updates running now, and all cached data is * synced to disk. We are now in a completely consistent state * which doesn't have anything in the journal, and we know that * no filesystem updates are running, so it is safe to modify * the inode's in-core data-journaling state flag now. */ if (val) ext4_set_inode_flag(inode, EXT4_INODE_JOURNAL_DATA); else { err = jbd2_journal_flush(journal, 0); if (err < 0) { jbd2_journal_unlock_updates(journal); ext4_writepages_up_write(inode->i_sb, alloc_ctx); return err; } ext4_clear_inode_flag(inode, EXT4_INODE_JOURNAL_DATA); } ext4_set_aops(inode); jbd2_journal_unlock_updates(journal); ext4_writepages_up_write(inode->i_sb, alloc_ctx); if (val) filemap_invalidate_unlock(inode->i_mapping); /* Finally we can mark the inode as dirty. */ handle = ext4_journal_start(inode, EXT4_HT_INODE, 1); if (IS_ERR(handle)) return PTR_ERR(handle); ext4_fc_mark_ineligible(inode->i_sb, EXT4_FC_REASON_JOURNAL_FLAG_CHANGE, handle); err = ext4_mark_inode_dirty(handle, inode); ext4_handle_sync(handle); ext4_journal_stop(handle); ext4_std_error(inode->i_sb, err); return err; } static int ext4_bh_unmapped(handle_t *handle, struct inode *inode, struct buffer_head *bh) { return !buffer_mapped(bh); } vm_fault_t ext4_page_mkwrite(struct vm_fault *vmf) { struct vm_area_struct *vma = vmf->vma; struct folio *folio = page_folio(vmf->page); loff_t size; unsigned long len; int err; vm_fault_t ret; struct file *file = vma->vm_file; struct inode *inode = file_inode(file); struct address_space *mapping = inode->i_mapping; handle_t *handle; get_block_t *get_block; int retries = 0; if (unlikely(IS_IMMUTABLE(inode))) return VM_FAULT_SIGBUS; sb_start_pagefault(inode->i_sb); file_update_time(vma->vm_file); filemap_invalidate_lock_shared(mapping); err = ext4_convert_inline_data(inode); if (err) goto out_ret; /* * On data journalling we skip straight to the transaction handle: * there's no delalloc; page truncated will be checked later; the * early return w/ all buffers mapped (calculates size/len) can't * be used; and there's no dioread_nolock, so only ext4_get_block. */ if (ext4_should_journal_data(inode)) goto retry_alloc; /* Delalloc case is easy... */ if (test_opt(inode->i_sb, DELALLOC) && !ext4_nonda_switch(inode->i_sb)) { do { err = block_page_mkwrite(vma, vmf, ext4_da_get_block_prep); } while (err == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries)); goto out_ret; } folio_lock(folio); size = i_size_read(inode); /* Page got truncated from under us? */ if (folio->mapping != mapping || folio_pos(folio) > size) { folio_unlock(folio); ret = VM_FAULT_NOPAGE; goto out; } len = folio_size(folio); if (folio_pos(folio) + len > size) len = size - folio_pos(folio); /* * Return if we have all the buffers mapped. This avoids the need to do * journal_start/journal_stop which can block and take a long time * * This cannot be done for data journalling, as we have to add the * inode to the transaction's list to writeprotect pages on commit. */ if (folio_buffers(folio)) { if (!ext4_walk_page_buffers(NULL, inode, folio_buffers(folio), 0, len, NULL, ext4_bh_unmapped)) { /* Wait so that we don't change page under IO */ folio_wait_stable(folio); ret = VM_FAULT_LOCKED; goto out; } } folio_unlock(folio); /* OK, we need to fill the hole... */ if (ext4_should_dioread_nolock(inode)) get_block = ext4_get_block_unwritten; else get_block = ext4_get_block; retry_alloc: handle = ext4_journal_start(inode, EXT4_HT_WRITE_PAGE, ext4_writepage_trans_blocks(inode)); if (IS_ERR(handle)) { ret = VM_FAULT_SIGBUS; goto out; } /* * Data journalling can't use block_page_mkwrite() because it * will set_buffer_dirty() before do_journal_get_write_access() * thus might hit warning messages for dirty metadata buffers. */ if (!ext4_should_journal_data(inode)) { err = block_page_mkwrite(vma, vmf, get_block); } else { folio_lock(folio); size = i_size_read(inode); /* Page got truncated from under us? */ if (folio->mapping != mapping || folio_pos(folio) > size) { ret = VM_FAULT_NOPAGE; goto out_error; } len = folio_size(folio); if (folio_pos(folio) + len > size) len = size - folio_pos(folio); err = __block_write_begin(&folio->page, 0, len, ext4_get_block); if (!err) { ret = VM_FAULT_SIGBUS; if (ext4_journal_folio_buffers(handle, folio, len)) goto out_error; } else { folio_unlock(folio); } } ext4_journal_stop(handle); if (err == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries)) goto retry_alloc; out_ret: ret = vmf_fs_error(err); out: filemap_invalidate_unlock_shared(mapping); sb_end_pagefault(inode->i_sb); return ret; out_error: folio_unlock(folio); ext4_journal_stop(handle); goto out; }
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