| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| Dave Kleikamp | 4865 | 32.06% | 1 | 0.48% |
| Tahsin Erdogan | 4460 | 29.39% | 31 | 14.98% |
| Jan Kara | 1314 | 8.66% | 27 | 13.04% |
| Theodore Y. Ts'o | 1180 | 7.78% | 47 | 22.71% |
| Andreas Dilger | 1175 | 7.74% | 2 | 0.97% |
| Kalpak Shah | 506 | 3.33% | 3 | 1.45% |
| Darrick J. Wong | 276 | 1.82% | 7 | 3.38% |
| Mingming Cao | 238 | 1.57% | 3 | 1.45% |
| Andreas Gruenbacher | 104 | 0.69% | 2 | 0.97% |
| Jun Nie | 88 | 0.58% | 2 | 0.97% |
| Eric Biggers | 74 | 0.49% | 6 | 2.90% |
| Tao Ma | 71 | 0.47% | 5 | 2.42% |
| Vasily Averin | 66 | 0.43% | 5 | 2.42% |
| Linus Torvalds | 54 | 0.36% | 2 | 0.97% |
| T Makphaibulchoke | 54 | 0.36% | 1 | 0.48% |
| Harshad Shirwadkar | 47 | 0.31% | 2 | 0.97% |
| Miao Xie | 42 | 0.28% | 2 | 0.97% |
| Christoph Hellwig | 42 | 0.28% | 4 | 1.93% |
| Jeff Layton | 37 | 0.24% | 5 | 2.42% |
| Joe Perches | 36 | 0.24% | 2 | 0.97% |
| Eric Whitney | 36 | 0.24% | 1 | 0.48% |
| Christian Brauner | 35 | 0.23% | 2 | 0.97% |
| Ye Bin | 33 | 0.22% | 3 | 1.45% |
| Tiger Yang | 32 | 0.21% | 1 | 0.48% |
| Baokun Li | 30 | 0.20% | 2 | 0.97% |
| Daeho Jeong | 29 | 0.19% | 1 | 0.48% |
| liang xie | 28 | 0.18% | 1 | 0.48% |
| Aneesh Kumar K.V | 22 | 0.14% | 3 | 1.45% |
| Lukas Czerner | 21 | 0.14% | 2 | 0.97% |
| Frank Mayhar | 19 | 0.13% | 1 | 0.48% |
| Eric Sandeen | 16 | 0.11% | 3 | 1.45% |
| Zhang Zhen | 14 | 0.09% | 1 | 0.48% |
| Jeffle Xu | 13 | 0.09% | 1 | 0.48% |
| David Howells | 12 | 0.08% | 1 | 0.48% |
| Dan Carpenter | 12 | 0.08% | 1 | 0.48% |
| lily | 11 | 0.07% | 1 | 0.48% |
| Jan (janneke) Nieuwenhuizen | 10 | 0.07% | 1 | 0.48% |
| Dmitriy Monakhov | 10 | 0.07% | 2 | 0.97% |
| Jaegeuk Kim | 9 | 0.06% | 1 | 0.48% |
| Shuqi Zhang | 8 | 0.05% | 1 | 0.48% |
| Li Xi | 6 | 0.04% | 1 | 0.48% |
| Xin Yin | 6 | 0.04% | 1 | 0.48% |
| Stephen Hemminger | 5 | 0.03% | 1 | 0.48% |
| zhangyi (F) | 4 | 0.03% | 1 | 0.48% |
| Shilong Wang | 4 | 0.03% | 2 | 0.97% |
| Nicholas Piggin | 3 | 0.02% | 1 | 0.48% |
| Roel Kluin | 3 | 0.02% | 1 | 0.48% |
| Josef Bacik | 2 | 0.01% | 1 | 0.48% |
| Allison Henderson | 2 | 0.01% | 1 | 0.48% |
| Akinobu Mita | 2 | 0.01% | 1 | 0.48% |
| Wang Sheng-Hui | 1 | 0.01% | 1 | 0.48% |
| Avantika Mathur | 1 | 0.01% | 1 | 0.48% |
| Wedson Almeida Filho | 1 | 0.01% | 1 | 0.48% |
| Bhaskar Chowdhury | 1 | 0.01% | 1 | 0.48% |
| Greg Kroah-Hartman | 1 | 0.01% | 1 | 0.48% |
| Peter Hüwe | 1 | 0.01% | 1 | 0.48% |
| Alex Tomas | 1 | 0.01% | 1 | 0.48% |
| Total | 15173 | 207 |
// SPDX-License-Identifier: GPL-2.0 /* * linux/fs/ext4/xattr.c * * Copyright (C) 2001-2003 Andreas Gruenbacher, <agruen@suse.de> * * Fix by Harrison Xing <harrison@mountainviewdata.com>. * Ext4 code with a lot of help from Eric Jarman <ejarman@acm.org>. * Extended attributes for symlinks and special files added per * suggestion of Luka Renko <luka.renko@hermes.si>. * xattr consolidation Copyright (c) 2004 James Morris <jmorris@redhat.com>, * Red Hat Inc. * ea-in-inode support by Alex Tomas <alex@clusterfs.com> aka bzzz * and Andreas Gruenbacher <agruen@suse.de>. */ /* * Extended attributes are stored directly in inodes (on file systems with * inodes bigger than 128 bytes) and on additional disk blocks. The i_file_acl * field contains the block number if an inode uses an additional block. All * attributes must fit in the inode and one additional block. Blocks that * contain the identical set of attributes may be shared among several inodes. * Identical blocks are detected by keeping a cache of blocks that have * recently been accessed. * * The attributes in inodes and on blocks have a different header; the entries * are stored in the same format: * * +------------------+ * | header | * | entry 1 | | * | entry 2 | | growing downwards * | entry 3 | v * | four null bytes | * | . . . | * | value 1 | ^ * | value 3 | | growing upwards * | value 2 | | * +------------------+ * * The header is followed by multiple entry descriptors. In disk blocks, the * entry descriptors are kept sorted. In inodes, they are unsorted. The * attribute values are aligned to the end of the block in no specific order. * * Locking strategy * ---------------- * EXT4_I(inode)->i_file_acl is protected by EXT4_I(inode)->xattr_sem. * EA blocks are only changed if they are exclusive to an inode, so * holding xattr_sem also means that nothing but the EA block's reference * count can change. Multiple writers to the same block are synchronized * by the buffer lock. */ #include <linux/init.h> #include <linux/fs.h> #include <linux/slab.h> #include <linux/mbcache.h> #include <linux/quotaops.h> #include <linux/iversion.h> #include "ext4_jbd2.h" #include "ext4.h" #include "xattr.h" #include "acl.h" #ifdef EXT4_XATTR_DEBUG # define ea_idebug(inode, fmt, ...) \ printk(KERN_DEBUG "inode %s:%lu: " fmt "\n", \ inode->i_sb->s_id, inode->i_ino, ##__VA_ARGS__) # define ea_bdebug(bh, fmt, ...) \ printk(KERN_DEBUG "block %pg:%lu: " fmt "\n", \ bh->b_bdev, (unsigned long)bh->b_blocknr, ##__VA_ARGS__) #else # define ea_idebug(inode, fmt, ...) no_printk(fmt, ##__VA_ARGS__) # define ea_bdebug(bh, fmt, ...) no_printk(fmt, ##__VA_ARGS__) #endif static void ext4_xattr_block_cache_insert(struct mb_cache *, struct buffer_head *); static struct buffer_head * ext4_xattr_block_cache_find(struct inode *, struct ext4_xattr_header *, struct mb_cache_entry **); static __le32 ext4_xattr_hash_entry(char *name, size_t name_len, __le32 *value, size_t value_count); static __le32 ext4_xattr_hash_entry_signed(char *name, size_t name_len, __le32 *value, size_t value_count); static void ext4_xattr_rehash(struct ext4_xattr_header *); static const struct xattr_handler * const ext4_xattr_handler_map[] = { [EXT4_XATTR_INDEX_USER] = &ext4_xattr_user_handler, #ifdef CONFIG_EXT4_FS_POSIX_ACL [EXT4_XATTR_INDEX_POSIX_ACL_ACCESS] = &nop_posix_acl_access, [EXT4_XATTR_INDEX_POSIX_ACL_DEFAULT] = &nop_posix_acl_default, #endif [EXT4_XATTR_INDEX_TRUSTED] = &ext4_xattr_trusted_handler, #ifdef CONFIG_EXT4_FS_SECURITY [EXT4_XATTR_INDEX_SECURITY] = &ext4_xattr_security_handler, #endif [EXT4_XATTR_INDEX_HURD] = &ext4_xattr_hurd_handler, }; const struct xattr_handler * const ext4_xattr_handlers[] = { &ext4_xattr_user_handler, &ext4_xattr_trusted_handler, #ifdef CONFIG_EXT4_FS_SECURITY &ext4_xattr_security_handler, #endif &ext4_xattr_hurd_handler, NULL }; #define EA_BLOCK_CACHE(inode) (((struct ext4_sb_info *) \ inode->i_sb->s_fs_info)->s_ea_block_cache) #define EA_INODE_CACHE(inode) (((struct ext4_sb_info *) \ inode->i_sb->s_fs_info)->s_ea_inode_cache) static int ext4_expand_inode_array(struct ext4_xattr_inode_array **ea_inode_array, struct inode *inode); #ifdef CONFIG_LOCKDEP void ext4_xattr_inode_set_class(struct inode *ea_inode) { struct ext4_inode_info *ei = EXT4_I(ea_inode); lockdep_set_subclass(&ea_inode->i_rwsem, 1); (void) ei; /* shut up clang warning if !CONFIG_LOCKDEP */ lockdep_set_subclass(&ei->i_data_sem, I_DATA_SEM_EA); } #endif static __le32 ext4_xattr_block_csum(struct inode *inode, sector_t block_nr, struct ext4_xattr_header *hdr) { struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); __u32 csum; __le64 dsk_block_nr = cpu_to_le64(block_nr); __u32 dummy_csum = 0; int offset = offsetof(struct ext4_xattr_header, h_checksum); csum = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&dsk_block_nr, sizeof(dsk_block_nr)); csum = ext4_chksum(sbi, csum, (__u8 *)hdr, offset); csum = ext4_chksum(sbi, csum, (__u8 *)&dummy_csum, sizeof(dummy_csum)); offset += sizeof(dummy_csum); csum = ext4_chksum(sbi, csum, (__u8 *)hdr + offset, EXT4_BLOCK_SIZE(inode->i_sb) - offset); return cpu_to_le32(csum); } static int ext4_xattr_block_csum_verify(struct inode *inode, struct buffer_head *bh) { struct ext4_xattr_header *hdr = BHDR(bh); int ret = 1; if (ext4_has_metadata_csum(inode->i_sb)) { lock_buffer(bh); ret = (hdr->h_checksum == ext4_xattr_block_csum(inode, bh->b_blocknr, hdr)); unlock_buffer(bh); } return ret; } static void ext4_xattr_block_csum_set(struct inode *inode, struct buffer_head *bh) { if (ext4_has_metadata_csum(inode->i_sb)) BHDR(bh)->h_checksum = ext4_xattr_block_csum(inode, bh->b_blocknr, BHDR(bh)); } static inline const char *ext4_xattr_prefix(int name_index, struct dentry *dentry) { const struct xattr_handler *handler = NULL; if (name_index > 0 && name_index < ARRAY_SIZE(ext4_xattr_handler_map)) handler = ext4_xattr_handler_map[name_index]; if (!xattr_handler_can_list(handler, dentry)) return NULL; return xattr_prefix(handler); } static int check_xattrs(struct inode *inode, struct buffer_head *bh, struct ext4_xattr_entry *entry, void *end, void *value_start, const char *function, unsigned int line) { struct ext4_xattr_entry *e = entry; int err = -EFSCORRUPTED; char *err_str; if (bh) { if (BHDR(bh)->h_magic != cpu_to_le32(EXT4_XATTR_MAGIC) || BHDR(bh)->h_blocks != cpu_to_le32(1)) { err_str = "invalid header"; goto errout; } if (buffer_verified(bh)) return 0; if (!ext4_xattr_block_csum_verify(inode, bh)) { err = -EFSBADCRC; err_str = "invalid checksum"; goto errout; } } else { struct ext4_xattr_ibody_header *header = value_start; header -= 1; if (end - (void *)header < sizeof(*header) + sizeof(u32)) { err_str = "in-inode xattr block too small"; goto errout; } if (header->h_magic != cpu_to_le32(EXT4_XATTR_MAGIC)) { err_str = "bad magic number in in-inode xattr"; goto errout; } } /* Find the end of the names list */ while (!IS_LAST_ENTRY(e)) { struct ext4_xattr_entry *next = EXT4_XATTR_NEXT(e); if ((void *)next >= end) { err_str = "e_name out of bounds"; goto errout; } if (strnlen(e->e_name, e->e_name_len) != e->e_name_len) { err_str = "bad e_name length"; goto errout; } e = next; } /* Check the values */ while (!IS_LAST_ENTRY(entry)) { u32 size = le32_to_cpu(entry->e_value_size); unsigned long ea_ino = le32_to_cpu(entry->e_value_inum); if (!ext4_has_feature_ea_inode(inode->i_sb) && ea_ino) { err_str = "ea_inode specified without ea_inode feature enabled"; goto errout; } if (ea_ino && ((ea_ino == EXT4_ROOT_INO) || !ext4_valid_inum(inode->i_sb, ea_ino))) { err_str = "invalid ea_ino"; goto errout; } if (size > EXT4_XATTR_SIZE_MAX) { err_str = "e_value size too large"; goto errout; } if (size != 0 && entry->e_value_inum == 0) { u16 offs = le16_to_cpu(entry->e_value_offs); void *value; /* * The value cannot overlap the names, and the value * with padding cannot extend beyond 'end'. Check both * the padded and unpadded sizes, since the size may * overflow to 0 when adding padding. */ if (offs > end - value_start) { err_str = "e_value out of bounds"; goto errout; } value = value_start + offs; if (value < (void *)e + sizeof(u32) || size > end - value || EXT4_XATTR_SIZE(size) > end - value) { err_str = "overlapping e_value "; goto errout; } } entry = EXT4_XATTR_NEXT(entry); } if (bh) set_buffer_verified(bh); return 0; errout: if (bh) __ext4_error_inode(inode, function, line, 0, -err, "corrupted xattr block %llu: %s", (unsigned long long) bh->b_blocknr, err_str); else __ext4_error_inode(inode, function, line, 0, -err, "corrupted in-inode xattr: %s", err_str); return err; } static inline int __ext4_xattr_check_block(struct inode *inode, struct buffer_head *bh, const char *function, unsigned int line) { return check_xattrs(inode, bh, BFIRST(bh), bh->b_data + bh->b_size, bh->b_data, function, line); } #define ext4_xattr_check_block(inode, bh) \ __ext4_xattr_check_block((inode), (bh), __func__, __LINE__) static inline int __xattr_check_inode(struct inode *inode, struct ext4_xattr_ibody_header *header, void *end, const char *function, unsigned int line) { return check_xattrs(inode, NULL, IFIRST(header), end, IFIRST(header), function, line); } #define xattr_check_inode(inode, header, end) \ __xattr_check_inode((inode), (header), (end), __func__, __LINE__) static int xattr_find_entry(struct inode *inode, struct ext4_xattr_entry **pentry, void *end, int name_index, const char *name, int sorted) { struct ext4_xattr_entry *entry, *next; size_t name_len; int cmp = 1; if (name == NULL) return -EINVAL; name_len = strlen(name); for (entry = *pentry; !IS_LAST_ENTRY(entry); entry = next) { next = EXT4_XATTR_NEXT(entry); if ((void *) next >= end) { EXT4_ERROR_INODE(inode, "corrupted xattr entries"); return -EFSCORRUPTED; } cmp = name_index - entry->e_name_index; if (!cmp) cmp = name_len - entry->e_name_len; if (!cmp) cmp = memcmp(name, entry->e_name, name_len); if (cmp <= 0 && (sorted || cmp == 0)) break; } *pentry = entry; return cmp ? -ENODATA : 0; } static u32 ext4_xattr_inode_hash(struct ext4_sb_info *sbi, const void *buffer, size_t size) { return ext4_chksum(sbi, sbi->s_csum_seed, buffer, size); } static u64 ext4_xattr_inode_get_ref(struct inode *ea_inode) { return ((u64) inode_get_ctime_sec(ea_inode) << 32) | (u32) inode_peek_iversion_raw(ea_inode); } static void ext4_xattr_inode_set_ref(struct inode *ea_inode, u64 ref_count) { inode_set_ctime(ea_inode, (u32)(ref_count >> 32), 0); inode_set_iversion_raw(ea_inode, ref_count & 0xffffffff); } static u32 ext4_xattr_inode_get_hash(struct inode *ea_inode) { return (u32) inode_get_atime_sec(ea_inode); } static void ext4_xattr_inode_set_hash(struct inode *ea_inode, u32 hash) { inode_set_atime(ea_inode, hash, 0); } /* * Read the EA value from an inode. */ static int ext4_xattr_inode_read(struct inode *ea_inode, void *buf, size_t size) { int blocksize = 1 << ea_inode->i_blkbits; int bh_count = (size + blocksize - 1) >> ea_inode->i_blkbits; int tail_size = (size % blocksize) ?: blocksize; struct buffer_head *bhs_inline[8]; struct buffer_head **bhs = bhs_inline; int i, ret; if (bh_count > ARRAY_SIZE(bhs_inline)) { bhs = kmalloc_array(bh_count, sizeof(*bhs), GFP_NOFS); if (!bhs) return -ENOMEM; } ret = ext4_bread_batch(ea_inode, 0 /* block */, bh_count, true /* wait */, bhs); if (ret) goto free_bhs; for (i = 0; i < bh_count; i++) { /* There shouldn't be any holes in ea_inode. */ if (!bhs[i]) { ret = -EFSCORRUPTED; goto put_bhs; } memcpy((char *)buf + blocksize * i, bhs[i]->b_data, i < bh_count - 1 ? blocksize : tail_size); } ret = 0; put_bhs: for (i = 0; i < bh_count; i++) brelse(bhs[i]); free_bhs: if (bhs != bhs_inline) kfree(bhs); return ret; } #define EXT4_XATTR_INODE_GET_PARENT(inode) ((__u32)(inode_get_mtime_sec(inode))) static int ext4_xattr_inode_iget(struct inode *parent, unsigned long ea_ino, u32 ea_inode_hash, struct inode **ea_inode) { struct inode *inode; int err; /* * We have to check for this corruption early as otherwise * iget_locked() could wait indefinitely for the state of our * parent inode. */ if (parent->i_ino == ea_ino) { ext4_error(parent->i_sb, "Parent and EA inode have the same ino %lu", ea_ino); return -EFSCORRUPTED; } inode = ext4_iget(parent->i_sb, ea_ino, EXT4_IGET_EA_INODE); if (IS_ERR(inode)) { err = PTR_ERR(inode); ext4_error(parent->i_sb, "error while reading EA inode %lu err=%d", ea_ino, err); return err; } ext4_xattr_inode_set_class(inode); /* * Check whether this is an old Lustre-style xattr inode. Lustre * implementation does not have hash validation, rather it has a * backpointer from ea_inode to the parent inode. */ if (ea_inode_hash != ext4_xattr_inode_get_hash(inode) && EXT4_XATTR_INODE_GET_PARENT(inode) == parent->i_ino && inode->i_generation == parent->i_generation) { ext4_set_inode_state(inode, EXT4_STATE_LUSTRE_EA_INODE); ext4_xattr_inode_set_ref(inode, 1); } else { inode_lock(inode); inode->i_flags |= S_NOQUOTA; inode_unlock(inode); } *ea_inode = inode; return 0; } /* Remove entry from mbcache when EA inode is getting evicted */ void ext4_evict_ea_inode(struct inode *inode) { struct mb_cache_entry *oe; if (!EA_INODE_CACHE(inode)) return; /* Wait for entry to get unused so that we can remove it */ while ((oe = mb_cache_entry_delete_or_get(EA_INODE_CACHE(inode), ext4_xattr_inode_get_hash(inode), inode->i_ino))) { mb_cache_entry_wait_unused(oe); mb_cache_entry_put(EA_INODE_CACHE(inode), oe); } } static int ext4_xattr_inode_verify_hashes(struct inode *ea_inode, struct ext4_xattr_entry *entry, void *buffer, size_t size) { u32 hash; /* Verify stored hash matches calculated hash. */ hash = ext4_xattr_inode_hash(EXT4_SB(ea_inode->i_sb), buffer, size); if (hash != ext4_xattr_inode_get_hash(ea_inode)) return -EFSCORRUPTED; if (entry) { __le32 e_hash, tmp_data; /* Verify entry hash. */ tmp_data = cpu_to_le32(hash); e_hash = ext4_xattr_hash_entry(entry->e_name, entry->e_name_len, &tmp_data, 1); /* All good? */ if (e_hash == entry->e_hash) return 0; /* * Not good. Maybe the entry hash was calculated * using the buggy signed char version? */ e_hash = ext4_xattr_hash_entry_signed(entry->e_name, entry->e_name_len, &tmp_data, 1); /* Still no match - bad */ if (e_hash != entry->e_hash) return -EFSCORRUPTED; /* Let people know about old hash */ pr_warn_once("ext4: filesystem with signed xattr name hash"); } return 0; } /* * Read xattr value from the EA inode. */ static int ext4_xattr_inode_get(struct inode *inode, struct ext4_xattr_entry *entry, void *buffer, size_t size) { struct mb_cache *ea_inode_cache = EA_INODE_CACHE(inode); struct inode *ea_inode; int err; err = ext4_xattr_inode_iget(inode, le32_to_cpu(entry->e_value_inum), le32_to_cpu(entry->e_hash), &ea_inode); if (err) { ea_inode = NULL; goto out; } if (i_size_read(ea_inode) != size) { ext4_warning_inode(ea_inode, "ea_inode file size=%llu entry size=%zu", i_size_read(ea_inode), size); err = -EFSCORRUPTED; goto out; } err = ext4_xattr_inode_read(ea_inode, buffer, size); if (err) goto out; if (!ext4_test_inode_state(ea_inode, EXT4_STATE_LUSTRE_EA_INODE)) { err = ext4_xattr_inode_verify_hashes(ea_inode, entry, buffer, size); if (err) { ext4_warning_inode(ea_inode, "EA inode hash validation failed"); goto out; } if (ea_inode_cache) mb_cache_entry_create(ea_inode_cache, GFP_NOFS, ext4_xattr_inode_get_hash(ea_inode), ea_inode->i_ino, true /* reusable */); } out: iput(ea_inode); return err; } static int ext4_xattr_block_get(struct inode *inode, int name_index, const char *name, void *buffer, size_t buffer_size) { struct buffer_head *bh = NULL; struct ext4_xattr_entry *entry; size_t size; void *end; int error; struct mb_cache *ea_block_cache = EA_BLOCK_CACHE(inode); ea_idebug(inode, "name=%d.%s, buffer=%p, buffer_size=%ld", name_index, name, buffer, (long)buffer_size); if (!EXT4_I(inode)->i_file_acl) return -ENODATA; ea_idebug(inode, "reading block %llu", (unsigned long long)EXT4_I(inode)->i_file_acl); bh = ext4_sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl, REQ_PRIO); if (IS_ERR(bh)) return PTR_ERR(bh); ea_bdebug(bh, "b_count=%d, refcount=%d", atomic_read(&(bh->b_count)), le32_to_cpu(BHDR(bh)->h_refcount)); error = ext4_xattr_check_block(inode, bh); if (error) goto cleanup; ext4_xattr_block_cache_insert(ea_block_cache, bh); entry = BFIRST(bh); end = bh->b_data + bh->b_size; error = xattr_find_entry(inode, &entry, end, name_index, name, 1); if (error) goto cleanup; size = le32_to_cpu(entry->e_value_size); error = -ERANGE; if (unlikely(size > EXT4_XATTR_SIZE_MAX)) goto cleanup; if (buffer) { if (size > buffer_size) goto cleanup; if (entry->e_value_inum) { error = ext4_xattr_inode_get(inode, entry, buffer, size); if (error) goto cleanup; } else { u16 offset = le16_to_cpu(entry->e_value_offs); void *p = bh->b_data + offset; if (unlikely(p + size > end)) goto cleanup; memcpy(buffer, p, size); } } error = size; cleanup: brelse(bh); return error; } int ext4_xattr_ibody_get(struct inode *inode, int name_index, const char *name, void *buffer, size_t buffer_size) { struct ext4_xattr_ibody_header *header; struct ext4_xattr_entry *entry; struct ext4_inode *raw_inode; struct ext4_iloc iloc; size_t size; void *end; int error; if (!ext4_test_inode_state(inode, EXT4_STATE_XATTR)) return -ENODATA; error = ext4_get_inode_loc(inode, &iloc); if (error) return error; raw_inode = ext4_raw_inode(&iloc); header = IHDR(inode, raw_inode); end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size; error = xattr_check_inode(inode, header, end); if (error) goto cleanup; entry = IFIRST(header); error = xattr_find_entry(inode, &entry, end, name_index, name, 0); if (error) goto cleanup; size = le32_to_cpu(entry->e_value_size); error = -ERANGE; if (unlikely(size > EXT4_XATTR_SIZE_MAX)) goto cleanup; if (buffer) { if (size > buffer_size) goto cleanup; if (entry->e_value_inum) { error = ext4_xattr_inode_get(inode, entry, buffer, size); if (error) goto cleanup; } else { u16 offset = le16_to_cpu(entry->e_value_offs); void *p = (void *)IFIRST(header) + offset; if (unlikely(p + size > end)) goto cleanup; memcpy(buffer, p, size); } } error = size; cleanup: brelse(iloc.bh); return error; } /* * ext4_xattr_get() * * Copy an extended attribute into the buffer * provided, or compute the buffer size required. * Buffer is NULL to compute the size of the buffer required. * * Returns a negative error number on failure, or the number of bytes * used / required on success. */ int ext4_xattr_get(struct inode *inode, int name_index, const char *name, void *buffer, size_t buffer_size) { int error; if (unlikely(ext4_forced_shutdown(inode->i_sb))) return -EIO; if (strlen(name) > 255) return -ERANGE; down_read(&EXT4_I(inode)->xattr_sem); error = ext4_xattr_ibody_get(inode, name_index, name, buffer, buffer_size); if (error == -ENODATA) error = ext4_xattr_block_get(inode, name_index, name, buffer, buffer_size); up_read(&EXT4_I(inode)->xattr_sem); return error; } static int ext4_xattr_list_entries(struct dentry *dentry, struct ext4_xattr_entry *entry, char *buffer, size_t buffer_size) { size_t rest = buffer_size; for (; !IS_LAST_ENTRY(entry); entry = EXT4_XATTR_NEXT(entry)) { const char *prefix; prefix = ext4_xattr_prefix(entry->e_name_index, dentry); if (prefix) { size_t prefix_len = strlen(prefix); size_t size = prefix_len + entry->e_name_len + 1; if (buffer) { if (size > rest) return -ERANGE; memcpy(buffer, prefix, prefix_len); buffer += prefix_len; memcpy(buffer, entry->e_name, entry->e_name_len); buffer += entry->e_name_len; *buffer++ = 0; } rest -= size; } } return buffer_size - rest; /* total size */ } static int ext4_xattr_block_list(struct dentry *dentry, char *buffer, size_t buffer_size) { struct inode *inode = d_inode(dentry); struct buffer_head *bh = NULL; int error; ea_idebug(inode, "buffer=%p, buffer_size=%ld", buffer, (long)buffer_size); if (!EXT4_I(inode)->i_file_acl) return 0; ea_idebug(inode, "reading block %llu", (unsigned long long)EXT4_I(inode)->i_file_acl); bh = ext4_sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl, REQ_PRIO); if (IS_ERR(bh)) return PTR_ERR(bh); ea_bdebug(bh, "b_count=%d, refcount=%d", atomic_read(&(bh->b_count)), le32_to_cpu(BHDR(bh)->h_refcount)); error = ext4_xattr_check_block(inode, bh); if (error) goto cleanup; ext4_xattr_block_cache_insert(EA_BLOCK_CACHE(inode), bh); error = ext4_xattr_list_entries(dentry, BFIRST(bh), buffer, buffer_size); cleanup: brelse(bh); return error; } static int ext4_xattr_ibody_list(struct dentry *dentry, char *buffer, size_t buffer_size) { struct inode *inode = d_inode(dentry); struct ext4_xattr_ibody_header *header; struct ext4_inode *raw_inode; struct ext4_iloc iloc; void *end; int error; if (!ext4_test_inode_state(inode, EXT4_STATE_XATTR)) return 0; error = ext4_get_inode_loc(inode, &iloc); if (error) return error; raw_inode = ext4_raw_inode(&iloc); header = IHDR(inode, raw_inode); end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size; error = xattr_check_inode(inode, header, end); if (error) goto cleanup; error = ext4_xattr_list_entries(dentry, IFIRST(header), buffer, buffer_size); cleanup: brelse(iloc.bh); return error; } /* * Inode operation listxattr() * * d_inode(dentry)->i_rwsem: don't care * * Copy a list of attribute names into the buffer * provided, or compute the buffer size required. * Buffer is NULL to compute the size of the buffer required. * * Returns a negative error number on failure, or the number of bytes * used / required on success. */ ssize_t ext4_listxattr(struct dentry *dentry, char *buffer, size_t buffer_size) { int ret, ret2; down_read(&EXT4_I(d_inode(dentry))->xattr_sem); ret = ret2 = ext4_xattr_ibody_list(dentry, buffer, buffer_size); if (ret < 0) goto errout; if (buffer) { buffer += ret; buffer_size -= ret; } ret = ext4_xattr_block_list(dentry, buffer, buffer_size); if (ret < 0) goto errout; ret += ret2; errout: up_read(&EXT4_I(d_inode(dentry))->xattr_sem); return ret; } /* * If the EXT4_FEATURE_COMPAT_EXT_ATTR feature of this file system is * not set, set it. */ static void ext4_xattr_update_super_block(handle_t *handle, struct super_block *sb) { if (ext4_has_feature_xattr(sb)) return; BUFFER_TRACE(EXT4_SB(sb)->s_sbh, "get_write_access"); if (ext4_journal_get_write_access(handle, sb, EXT4_SB(sb)->s_sbh, EXT4_JTR_NONE) == 0) { lock_buffer(EXT4_SB(sb)->s_sbh); ext4_set_feature_xattr(sb); ext4_superblock_csum_set(sb); unlock_buffer(EXT4_SB(sb)->s_sbh); ext4_handle_dirty_metadata(handle, NULL, EXT4_SB(sb)->s_sbh); } } int ext4_get_inode_usage(struct inode *inode, qsize_t *usage) { struct ext4_iloc iloc = { .bh = NULL }; struct buffer_head *bh = NULL; struct ext4_inode *raw_inode; struct ext4_xattr_ibody_header *header; struct ext4_xattr_entry *entry; qsize_t ea_inode_refs = 0; void *end; int ret; lockdep_assert_held_read(&EXT4_I(inode)->xattr_sem); if (ext4_test_inode_state(inode, EXT4_STATE_XATTR)) { ret = ext4_get_inode_loc(inode, &iloc); if (ret) goto out; raw_inode = ext4_raw_inode(&iloc); header = IHDR(inode, raw_inode); end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size; ret = xattr_check_inode(inode, header, end); if (ret) goto out; for (entry = IFIRST(header); !IS_LAST_ENTRY(entry); entry = EXT4_XATTR_NEXT(entry)) if (entry->e_value_inum) ea_inode_refs++; } if (EXT4_I(inode)->i_file_acl) { bh = ext4_sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl, REQ_PRIO); if (IS_ERR(bh)) { ret = PTR_ERR(bh); bh = NULL; goto out; } ret = ext4_xattr_check_block(inode, bh); if (ret) goto out; for (entry = BFIRST(bh); !IS_LAST_ENTRY(entry); entry = EXT4_XATTR_NEXT(entry)) if (entry->e_value_inum) ea_inode_refs++; } *usage = ea_inode_refs + 1; ret = 0; out: brelse(iloc.bh); brelse(bh); return ret; } static inline size_t round_up_cluster(struct inode *inode, size_t length) { struct super_block *sb = inode->i_sb; size_t cluster_size = 1 << (EXT4_SB(sb)->s_cluster_bits + inode->i_blkbits); size_t mask = ~(cluster_size - 1); return (length + cluster_size - 1) & mask; } static int ext4_xattr_inode_alloc_quota(struct inode *inode, size_t len) { int err; err = dquot_alloc_inode(inode); if (err) return err; err = dquot_alloc_space_nodirty(inode, round_up_cluster(inode, len)); if (err) dquot_free_inode(inode); return err; } static void ext4_xattr_inode_free_quota(struct inode *parent, struct inode *ea_inode, size_t len) { if (ea_inode && ext4_test_inode_state(ea_inode, EXT4_STATE_LUSTRE_EA_INODE)) return; dquot_free_space_nodirty(parent, round_up_cluster(parent, len)); dquot_free_inode(parent); } int __ext4_xattr_set_credits(struct super_block *sb, struct inode *inode, struct buffer_head *block_bh, size_t value_len, bool is_create) { int credits; int blocks; /* * 1) Owner inode update * 2) Ref count update on old xattr block * 3) new xattr block * 4) block bitmap update for new xattr block * 5) group descriptor for new xattr block * 6) block bitmap update for old xattr block * 7) group descriptor for old block * * 6 & 7 can happen if we have two racing threads T_a and T_b * which are each trying to set an xattr on inodes I_a and I_b * which were both initially sharing an xattr block. */ credits = 7; /* Quota updates. */ credits += EXT4_MAXQUOTAS_TRANS_BLOCKS(sb); /* * In case of inline data, we may push out the data to a block, * so we need to reserve credits for this eventuality */ if (inode && ext4_has_inline_data(inode)) credits += ext4_writepage_trans_blocks(inode) + 1; /* We are done if ea_inode feature is not enabled. */ if (!ext4_has_feature_ea_inode(sb)) return credits; /* New ea_inode, inode map, block bitmap, group descriptor. */ credits += 4; /* Data blocks. */ blocks = (value_len + sb->s_blocksize - 1) >> sb->s_blocksize_bits; /* Indirection block or one level of extent tree. */ blocks += 1; /* Block bitmap and group descriptor updates for each block. */ credits += blocks * 2; /* Blocks themselves. */ credits += blocks; if (!is_create) { /* Dereference ea_inode holding old xattr value. * Old ea_inode, inode map, block bitmap, group descriptor. */ credits += 4; /* Data blocks for old ea_inode. */ blocks = XATTR_SIZE_MAX >> sb->s_blocksize_bits; /* Indirection block or one level of extent tree for old * ea_inode. */ blocks += 1; /* Block bitmap and group descriptor updates for each block. */ credits += blocks * 2; } /* We may need to clone the existing xattr block in which case we need * to increment ref counts for existing ea_inodes referenced by it. */ if (block_bh) { struct ext4_xattr_entry *entry = BFIRST(block_bh); for (; !IS_LAST_ENTRY(entry); entry = EXT4_XATTR_NEXT(entry)) if (entry->e_value_inum) /* Ref count update on ea_inode. */ credits += 1; } return credits; } static int ext4_xattr_inode_update_ref(handle_t *handle, struct inode *ea_inode, int ref_change) { struct ext4_iloc iloc; s64 ref_count; int ret; inode_lock(ea_inode); ret = ext4_reserve_inode_write(handle, ea_inode, &iloc); if (ret) goto out; ref_count = ext4_xattr_inode_get_ref(ea_inode); ref_count += ref_change; ext4_xattr_inode_set_ref(ea_inode, ref_count); if (ref_change > 0) { WARN_ONCE(ref_count <= 0, "EA inode %lu ref_count=%lld", ea_inode->i_ino, ref_count); if (ref_count == 1) { WARN_ONCE(ea_inode->i_nlink, "EA inode %lu i_nlink=%u", ea_inode->i_ino, ea_inode->i_nlink); set_nlink(ea_inode, 1); ext4_orphan_del(handle, ea_inode); } } else { WARN_ONCE(ref_count < 0, "EA inode %lu ref_count=%lld", ea_inode->i_ino, ref_count); if (ref_count == 0) { WARN_ONCE(ea_inode->i_nlink != 1, "EA inode %lu i_nlink=%u", ea_inode->i_ino, ea_inode->i_nlink); clear_nlink(ea_inode); ext4_orphan_add(handle, ea_inode); } } ret = ext4_mark_iloc_dirty(handle, ea_inode, &iloc); if (ret) ext4_warning_inode(ea_inode, "ext4_mark_iloc_dirty() failed ret=%d", ret); out: inode_unlock(ea_inode); return ret; } static int ext4_xattr_inode_inc_ref(handle_t *handle, struct inode *ea_inode) { return ext4_xattr_inode_update_ref(handle, ea_inode, 1); } static int ext4_xattr_inode_dec_ref(handle_t *handle, struct inode *ea_inode) { return ext4_xattr_inode_update_ref(handle, ea_inode, -1); } static int ext4_xattr_inode_inc_ref_all(handle_t *handle, struct inode *parent, struct ext4_xattr_entry *first) { struct inode *ea_inode; struct ext4_xattr_entry *entry; struct ext4_xattr_entry *failed_entry; unsigned int ea_ino; int err, saved_err; for (entry = first; !IS_LAST_ENTRY(entry); entry = EXT4_XATTR_NEXT(entry)) { if (!entry->e_value_inum) continue; ea_ino = le32_to_cpu(entry->e_value_inum); err = ext4_xattr_inode_iget(parent, ea_ino, le32_to_cpu(entry->e_hash), &ea_inode); if (err) goto cleanup; err = ext4_xattr_inode_inc_ref(handle, ea_inode); if (err) { ext4_warning_inode(ea_inode, "inc ref error %d", err); iput(ea_inode); goto cleanup; } iput(ea_inode); } return 0; cleanup: saved_err = err; failed_entry = entry; for (entry = first; entry != failed_entry; entry = EXT4_XATTR_NEXT(entry)) { if (!entry->e_value_inum) continue; ea_ino = le32_to_cpu(entry->e_value_inum); err = ext4_xattr_inode_iget(parent, ea_ino, le32_to_cpu(entry->e_hash), &ea_inode); if (err) { ext4_warning(parent->i_sb, "cleanup ea_ino %u iget error %d", ea_ino, err); continue; } err = ext4_xattr_inode_dec_ref(handle, ea_inode); if (err) ext4_warning_inode(ea_inode, "cleanup dec ref error %d", err); iput(ea_inode); } return saved_err; } static int ext4_xattr_restart_fn(handle_t *handle, struct inode *inode, struct buffer_head *bh, bool block_csum, bool dirty) { int error; if (bh && dirty) { if (block_csum) ext4_xattr_block_csum_set(inode, bh); error = ext4_handle_dirty_metadata(handle, NULL, bh); if (error) { ext4_warning(inode->i_sb, "Handle metadata (error %d)", error); return error; } } return 0; } static void ext4_xattr_inode_dec_ref_all(handle_t *handle, struct inode *parent, struct buffer_head *bh, struct ext4_xattr_entry *first, bool block_csum, struct ext4_xattr_inode_array **ea_inode_array, int extra_credits, bool skip_quota) { struct inode *ea_inode; struct ext4_xattr_entry *entry; bool dirty = false; unsigned int ea_ino; int err; int credits; /* One credit for dec ref on ea_inode, one for orphan list addition, */ credits = 2 + extra_credits; for (entry = first; !IS_LAST_ENTRY(entry); entry = EXT4_XATTR_NEXT(entry)) { if (!entry->e_value_inum) continue; ea_ino = le32_to_cpu(entry->e_value_inum); err = ext4_xattr_inode_iget(parent, ea_ino, le32_to_cpu(entry->e_hash), &ea_inode); if (err) continue; err = ext4_expand_inode_array(ea_inode_array, ea_inode); if (err) { ext4_warning_inode(ea_inode, "Expand inode array err=%d", err); iput(ea_inode); continue; } err = ext4_journal_ensure_credits_fn(handle, credits, credits, ext4_free_metadata_revoke_credits(parent->i_sb, 1), ext4_xattr_restart_fn(handle, parent, bh, block_csum, dirty)); if (err < 0) { ext4_warning_inode(ea_inode, "Ensure credits err=%d", err); continue; } if (err > 0) { err = ext4_journal_get_write_access(handle, parent->i_sb, bh, EXT4_JTR_NONE); if (err) { ext4_warning_inode(ea_inode, "Re-get write access err=%d", err); continue; } } err = ext4_xattr_inode_dec_ref(handle, ea_inode); if (err) { ext4_warning_inode(ea_inode, "ea_inode dec ref err=%d", err); continue; } if (!skip_quota) ext4_xattr_inode_free_quota(parent, ea_inode, le32_to_cpu(entry->e_value_size)); /* * Forget about ea_inode within the same transaction that * decrements the ref count. This avoids duplicate decrements in * case the rest of the work spills over to subsequent * transactions. */ entry->e_value_inum = 0; entry->e_value_size = 0; dirty = true; } if (dirty) { /* * Note that we are deliberately skipping csum calculation for * the final update because we do not expect any journal * restarts until xattr block is freed. */ err = ext4_handle_dirty_metadata(handle, NULL, bh); if (err) ext4_warning_inode(parent, "handle dirty metadata err=%d", err); } } /* * Release the xattr block BH: If the reference count is > 1, decrement it; * otherwise free the block. */ static void ext4_xattr_release_block(handle_t *handle, struct inode *inode, struct buffer_head *bh, struct ext4_xattr_inode_array **ea_inode_array, int extra_credits) { struct mb_cache *ea_block_cache = EA_BLOCK_CACHE(inode); u32 hash, ref; int error = 0; BUFFER_TRACE(bh, "get_write_access"); error = ext4_journal_get_write_access(handle, inode->i_sb, bh, EXT4_JTR_NONE); if (error) goto out; retry_ref: lock_buffer(bh); hash = le32_to_cpu(BHDR(bh)->h_hash); ref = le32_to_cpu(BHDR(bh)->h_refcount); if (ref == 1) { ea_bdebug(bh, "refcount now=0; freeing"); /* * This must happen under buffer lock for * ext4_xattr_block_set() to reliably detect freed block */ if (ea_block_cache) { struct mb_cache_entry *oe; oe = mb_cache_entry_delete_or_get(ea_block_cache, hash, bh->b_blocknr); if (oe) { unlock_buffer(bh); mb_cache_entry_wait_unused(oe); mb_cache_entry_put(ea_block_cache, oe); goto retry_ref; } } get_bh(bh); unlock_buffer(bh); if (ext4_has_feature_ea_inode(inode->i_sb)) ext4_xattr_inode_dec_ref_all(handle, inode, bh, BFIRST(bh), true /* block_csum */, ea_inode_array, extra_credits, true /* skip_quota */); ext4_free_blocks(handle, inode, bh, 0, 1, EXT4_FREE_BLOCKS_METADATA | EXT4_FREE_BLOCKS_FORGET); } else { ref--; BHDR(bh)->h_refcount = cpu_to_le32(ref); if (ref == EXT4_XATTR_REFCOUNT_MAX - 1) { struct mb_cache_entry *ce; if (ea_block_cache) { ce = mb_cache_entry_get(ea_block_cache, hash, bh->b_blocknr); if (ce) { set_bit(MBE_REUSABLE_B, &ce->e_flags); mb_cache_entry_put(ea_block_cache, ce); } } } ext4_xattr_block_csum_set(inode, bh); /* * Beware of this ugliness: Releasing of xattr block references * from different inodes can race and so we have to protect * from a race where someone else frees the block (and releases * its journal_head) before we are done dirtying the buffer. In * nojournal mode this race is harmless and we actually cannot * call ext4_handle_dirty_metadata() with locked buffer as * that function can call sync_dirty_buffer() so for that case * we handle the dirtying after unlocking the buffer. */ if (ext4_handle_valid(handle)) error = ext4_handle_dirty_metadata(handle, inode, bh); unlock_buffer(bh); if (!ext4_handle_valid(handle)) error = ext4_handle_dirty_metadata(handle, inode, bh); if (IS_SYNC(inode)) ext4_handle_sync(handle); dquot_free_block(inode, EXT4_C2B(EXT4_SB(inode->i_sb), 1)); ea_bdebug(bh, "refcount now=%d; releasing", le32_to_cpu(BHDR(bh)->h_refcount)); } out: ext4_std_error(inode->i_sb, error); return; } /* * Find the available free space for EAs. This also returns the total number of * bytes used by EA entries. */ static size_t ext4_xattr_free_space(struct ext4_xattr_entry *last, size_t *min_offs, void *base, int *total) { for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) { if (!last->e_value_inum && last->e_value_size) { size_t offs = le16_to_cpu(last->e_value_offs); if (offs < *min_offs) *min_offs = offs; } if (total) *total += EXT4_XATTR_LEN(last->e_name_len); } return (*min_offs - ((void *)last - base) - sizeof(__u32)); } /* * Write the value of the EA in an inode. */ static int ext4_xattr_inode_write(handle_t *handle, struct inode *ea_inode, const void *buf, int bufsize) { struct buffer_head *bh = NULL; unsigned long block = 0; int blocksize = ea_inode->i_sb->s_blocksize; int max_blocks = (bufsize + blocksize - 1) >> ea_inode->i_blkbits; int csize, wsize = 0; int ret = 0, ret2 = 0; int retries = 0; retry: while (ret >= 0 && ret < max_blocks) { struct ext4_map_blocks map; map.m_lblk = block += ret; map.m_len = max_blocks -= ret; ret = ext4_map_blocks(handle, ea_inode, &map, EXT4_GET_BLOCKS_CREATE); if (ret <= 0) { ext4_mark_inode_dirty(handle, ea_inode); if (ret == -ENOSPC && ext4_should_retry_alloc(ea_inode->i_sb, &retries)) { ret = 0; goto retry; } break; } } if (ret < 0) return ret; block = 0; while (wsize < bufsize) { brelse(bh); csize = (bufsize - wsize) > blocksize ? blocksize : bufsize - wsize; bh = ext4_getblk(handle, ea_inode, block, 0); if (IS_ERR(bh)) return PTR_ERR(bh); if (!bh) { WARN_ON_ONCE(1); EXT4_ERROR_INODE(ea_inode, "ext4_getblk() return bh = NULL"); return -EFSCORRUPTED; } ret = ext4_journal_get_write_access(handle, ea_inode->i_sb, bh, EXT4_JTR_NONE); if (ret) goto out; memcpy(bh->b_data, buf, csize); set_buffer_uptodate(bh); ext4_handle_dirty_metadata(handle, ea_inode, bh); buf += csize; wsize += csize; block += 1; } inode_lock(ea_inode); i_size_write(ea_inode, wsize); ext4_update_i_disksize(ea_inode, wsize); inode_unlock(ea_inode); ret2 = ext4_mark_inode_dirty(handle, ea_inode); if (unlikely(ret2 && !ret)) ret = ret2; out: brelse(bh); return ret; } /* * Create an inode to store the value of a large EA. */ static struct inode *ext4_xattr_inode_create(handle_t *handle, struct inode *inode, u32 hash) { struct inode *ea_inode = NULL; uid_t owner[2] = { i_uid_read(inode), i_gid_read(inode) }; int err; if (inode->i_sb->s_root == NULL) { ext4_warning(inode->i_sb, "refuse to create EA inode when umounting"); WARN_ON(1); return ERR_PTR(-EINVAL); } /* * Let the next inode be the goal, so we try and allocate the EA inode * in the same group, or nearby one. */ ea_inode = ext4_new_inode(handle, inode->i_sb->s_root->d_inode, S_IFREG | 0600, NULL, inode->i_ino + 1, owner, EXT4_EA_INODE_FL); if (!IS_ERR(ea_inode)) { ea_inode->i_op = &ext4_file_inode_operations; ea_inode->i_fop = &ext4_file_operations; ext4_set_aops(ea_inode); ext4_xattr_inode_set_class(ea_inode); unlock_new_inode(ea_inode); ext4_xattr_inode_set_ref(ea_inode, 1); ext4_xattr_inode_set_hash(ea_inode, hash); err = ext4_mark_inode_dirty(handle, ea_inode); if (!err) err = ext4_inode_attach_jinode(ea_inode); if (err) { if (ext4_xattr_inode_dec_ref(handle, ea_inode)) ext4_warning_inode(ea_inode, "cleanup dec ref error %d", err); iput(ea_inode); return ERR_PTR(err); } /* * Xattr inodes are shared therefore quota charging is performed * at a higher level. */ dquot_free_inode(ea_inode); dquot_drop(ea_inode); inode_lock(ea_inode); ea_inode->i_flags |= S_NOQUOTA; inode_unlock(ea_inode); } return ea_inode; } static struct inode * ext4_xattr_inode_cache_find(struct inode *inode, const void *value, size_t value_len, u32 hash) { struct inode *ea_inode; struct mb_cache_entry *ce; struct mb_cache *ea_inode_cache = EA_INODE_CACHE(inode); void *ea_data; if (!ea_inode_cache) return NULL; ce = mb_cache_entry_find_first(ea_inode_cache, hash); if (!ce) return NULL; WARN_ON_ONCE(ext4_handle_valid(journal_current_handle()) && !(current->flags & PF_MEMALLOC_NOFS)); ea_data = kvmalloc(value_len, GFP_KERNEL); if (!ea_data) { mb_cache_entry_put(ea_inode_cache, ce); return NULL; } while (ce) { ea_inode = ext4_iget(inode->i_sb, ce->e_value, EXT4_IGET_EA_INODE); if (IS_ERR(ea_inode)) goto next_entry; ext4_xattr_inode_set_class(ea_inode); if (i_size_read(ea_inode) == value_len && !ext4_xattr_inode_read(ea_inode, ea_data, value_len) && !ext4_xattr_inode_verify_hashes(ea_inode, NULL, ea_data, value_len) && !memcmp(value, ea_data, value_len)) { mb_cache_entry_touch(ea_inode_cache, ce); mb_cache_entry_put(ea_inode_cache, ce); kvfree(ea_data); return ea_inode; } iput(ea_inode); next_entry: ce = mb_cache_entry_find_next(ea_inode_cache, ce); } kvfree(ea_data); return NULL; } /* * Add value of the EA in an inode. */ static int ext4_xattr_inode_lookup_create(handle_t *handle, struct inode *inode, const void *value, size_t value_len, struct inode **ret_inode) { struct inode *ea_inode; u32 hash; int err; hash = ext4_xattr_inode_hash(EXT4_SB(inode->i_sb), value, value_len); ea_inode = ext4_xattr_inode_cache_find(inode, value, value_len, hash); if (ea_inode) { err = ext4_xattr_inode_inc_ref(handle, ea_inode); if (err) { iput(ea_inode); return err; } *ret_inode = ea_inode; return 0; } /* Create an inode for the EA value */ ea_inode = ext4_xattr_inode_create(handle, inode, hash); if (IS_ERR(ea_inode)) return PTR_ERR(ea_inode); err = ext4_xattr_inode_write(handle, ea_inode, value, value_len); if (err) { if (ext4_xattr_inode_dec_ref(handle, ea_inode)) ext4_warning_inode(ea_inode, "cleanup dec ref error %d", err); iput(ea_inode); return err; } if (EA_INODE_CACHE(inode)) mb_cache_entry_create(EA_INODE_CACHE(inode), GFP_NOFS, hash, ea_inode->i_ino, true /* reusable */); *ret_inode = ea_inode; return 0; } /* * Reserve min(block_size/8, 1024) bytes for xattr entries/names if ea_inode * feature is enabled. */ #define EXT4_XATTR_BLOCK_RESERVE(inode) min(i_blocksize(inode)/8, 1024U) static int ext4_xattr_set_entry(struct ext4_xattr_info *i, struct ext4_xattr_search *s, handle_t *handle, struct inode *inode, bool is_block) { struct ext4_xattr_entry *last, *next; struct ext4_xattr_entry *here = s->here; size_t min_offs = s->end - s->base, name_len = strlen(i->name); int in_inode = i->in_inode; struct inode *old_ea_inode = NULL; struct inode *new_ea_inode = NULL; size_t old_size, new_size; int ret; /* Space used by old and new values. */ old_size = (!s->not_found && !here->e_value_inum) ? EXT4_XATTR_SIZE(le32_to_cpu(here->e_value_size)) : 0; new_size = (i->value && !in_inode) ? EXT4_XATTR_SIZE(i->value_len) : 0; /* * Optimization for the simple case when old and new values have the * same padded sizes. Not applicable if external inodes are involved. */ if (new_size && new_size == old_size) { size_t offs = le16_to_cpu(here->e_value_offs); void *val = s->base + offs; here->e_value_size = cpu_to_le32(i->value_len); if (i->value == EXT4_ZERO_XATTR_VALUE) { memset(val, 0, new_size); } else { memcpy(val, i->value, i->value_len); /* Clear padding bytes. */ memset(val + i->value_len, 0, new_size - i->value_len); } goto update_hash; } /* Compute min_offs and last. */ last = s->first; for (; !IS_LAST_ENTRY(last); last = next) { next = EXT4_XATTR_NEXT(last); if ((void *)next >= s->end) { EXT4_ERROR_INODE(inode, "corrupted xattr entries"); ret = -EFSCORRUPTED; goto out; } if (!last->e_value_inum && last->e_value_size) { size_t offs = le16_to_cpu(last->e_value_offs); if (offs < min_offs) min_offs = offs; } } /* Check whether we have enough space. */ if (i->value) { size_t free; free = min_offs - ((void *)last - s->base) - sizeof(__u32); if (!s->not_found) free += EXT4_XATTR_LEN(name_len) + old_size; if (free < EXT4_XATTR_LEN(name_len) + new_size) { ret = -ENOSPC; goto out; } /* * If storing the value in an external inode is an option, * reserve space for xattr entries/names in the external * attribute block so that a long value does not occupy the * whole space and prevent further entries being added. */ if (ext4_has_feature_ea_inode(inode->i_sb) && new_size && is_block && (min_offs + old_size - new_size) < EXT4_XATTR_BLOCK_RESERVE(inode)) { ret = -ENOSPC; goto out; } } /* * Getting access to old and new ea inodes is subject to failures. * Finish that work before doing any modifications to the xattr data. */ if (!s->not_found && here->e_value_inum) { ret = ext4_xattr_inode_iget(inode, le32_to_cpu(here->e_value_inum), le32_to_cpu(here->e_hash), &old_ea_inode); if (ret) { old_ea_inode = NULL; goto out; } } if (i->value && in_inode) { WARN_ON_ONCE(!i->value_len); ret = ext4_xattr_inode_alloc_quota(inode, i->value_len); if (ret) goto out; ret = ext4_xattr_inode_lookup_create(handle, inode, i->value, i->value_len, &new_ea_inode); if (ret) { new_ea_inode = NULL; ext4_xattr_inode_free_quota(inode, NULL, i->value_len); goto out; } } if (old_ea_inode) { /* We are ready to release ref count on the old_ea_inode. */ ret = ext4_xattr_inode_dec_ref(handle, old_ea_inode); if (ret) { /* Release newly required ref count on new_ea_inode. */ if (new_ea_inode) { int err; err = ext4_xattr_inode_dec_ref(handle, new_ea_inode); if (err) ext4_warning_inode(new_ea_inode, "dec ref new_ea_inode err=%d", err); ext4_xattr_inode_free_quota(inode, new_ea_inode, i->value_len); } goto out; } ext4_xattr_inode_free_quota(inode, old_ea_inode, le32_to_cpu(here->e_value_size)); } /* No failures allowed past this point. */ if (!s->not_found && here->e_value_size && !here->e_value_inum) { /* Remove the old value. */ void *first_val = s->base + min_offs; size_t offs = le16_to_cpu(here->e_value_offs); void *val = s->base + offs; memmove(first_val + old_size, first_val, val - first_val); memset(first_val, 0, old_size); min_offs += old_size; /* Adjust all value offsets. */ last = s->first; while (!IS_LAST_ENTRY(last)) { size_t o = le16_to_cpu(last->e_value_offs); if (!last->e_value_inum && last->e_value_size && o < offs) last->e_value_offs = cpu_to_le16(o + old_size); last = EXT4_XATTR_NEXT(last); } } if (!i->value) { /* Remove old name. */ size_t size = EXT4_XATTR_LEN(name_len); last = ENTRY((void *)last - size); memmove(here, (void *)here + size, (void *)last - (void *)here + sizeof(__u32)); memset(last, 0, size); /* * Update i_inline_off - moved ibody region might contain * system.data attribute. Handling a failure here won't * cause other complications for setting an xattr. */ if (!is_block && ext4_has_inline_data(inode)) { ret = ext4_find_inline_data_nolock(inode); if (ret) { ext4_warning_inode(inode, "unable to update i_inline_off"); goto out; } } } else if (s->not_found) { /* Insert new name. */ size_t size = EXT4_XATTR_LEN(name_len); size_t rest = (void *)last - (void *)here + sizeof(__u32); memmove((void *)here + size, here, rest); memset(here, 0, size); here->e_name_index = i->name_index; here->e_name_len = name_len; memcpy(here->e_name, i->name, name_len); } else { /* This is an update, reset value info. */ here->e_value_inum = 0; here->e_value_offs = 0; here->e_value_size = 0; } if (i->value) { /* Insert new value. */ if (in_inode) { here->e_value_inum = cpu_to_le32(new_ea_inode->i_ino); } else if (i->value_len) { void *val = s->base + min_offs - new_size; here->e_value_offs = cpu_to_le16(min_offs - new_size); if (i->value == EXT4_ZERO_XATTR_VALUE) { memset(val, 0, new_size); } else { memcpy(val, i->value, i->value_len); /* Clear padding bytes. */ memset(val + i->value_len, 0, new_size - i->value_len); } } here->e_value_size = cpu_to_le32(i->value_len); } update_hash: if (i->value) { __le32 hash = 0; /* Entry hash calculation. */ if (in_inode) { __le32 crc32c_hash; /* * Feed crc32c hash instead of the raw value for entry * hash calculation. This is to avoid walking * potentially long value buffer again. */ crc32c_hash = cpu_to_le32( ext4_xattr_inode_get_hash(new_ea_inode)); hash = ext4_xattr_hash_entry(here->e_name, here->e_name_len, &crc32c_hash, 1); } else if (is_block) { __le32 *value = s->base + le16_to_cpu( here->e_value_offs); hash = ext4_xattr_hash_entry(here->e_name, here->e_name_len, value, new_size >> 2); } here->e_hash = hash; } if (is_block) ext4_xattr_rehash((struct ext4_xattr_header *)s->base); ret = 0; out: iput(old_ea_inode); iput(new_ea_inode); return ret; } struct ext4_xattr_block_find { struct ext4_xattr_search s; struct buffer_head *bh; }; static int ext4_xattr_block_find(struct inode *inode, struct ext4_xattr_info *i, struct ext4_xattr_block_find *bs) { struct super_block *sb = inode->i_sb; int error; ea_idebug(inode, "name=%d.%s, value=%p, value_len=%ld", i->name_index, i->name, i->value, (long)i->value_len); if (EXT4_I(inode)->i_file_acl) { /* The inode already has an extended attribute block. */ bs->bh = ext4_sb_bread(sb, EXT4_I(inode)->i_file_acl, REQ_PRIO); if (IS_ERR(bs->bh)) { error = PTR_ERR(bs->bh); bs->bh = NULL; return error; } ea_bdebug(bs->bh, "b_count=%d, refcount=%d", atomic_read(&(bs->bh->b_count)), le32_to_cpu(BHDR(bs->bh)->h_refcount)); error = ext4_xattr_check_block(inode, bs->bh); if (error) return error; /* Find the named attribute. */ bs->s.base = BHDR(bs->bh); bs->s.first = BFIRST(bs->bh); bs->s.end = bs->bh->b_data + bs->bh->b_size; bs->s.here = bs->s.first; error = xattr_find_entry(inode, &bs->s.here, bs->s.end, i->name_index, i->name, 1); if (error && error != -ENODATA) return error; bs->s.not_found = error; } return 0; } static int ext4_xattr_block_set(handle_t *handle, struct inode *inode, struct ext4_xattr_info *i, struct ext4_xattr_block_find *bs) { struct super_block *sb = inode->i_sb; struct buffer_head *new_bh = NULL; struct ext4_xattr_search s_copy = bs->s; struct ext4_xattr_search *s = &s_copy; struct mb_cache_entry *ce = NULL; int error = 0; struct mb_cache *ea_block_cache = EA_BLOCK_CACHE(inode); struct inode *ea_inode = NULL, *tmp_inode; size_t old_ea_inode_quota = 0; unsigned int ea_ino; #define header(x) ((struct ext4_xattr_header *)(x)) if (s->base) { int offset = (char *)s->here - bs->bh->b_data; BUFFER_TRACE(bs->bh, "get_write_access"); error = ext4_journal_get_write_access(handle, sb, bs->bh, EXT4_JTR_NONE); if (error) goto cleanup; lock_buffer(bs->bh); if (header(s->base)->h_refcount == cpu_to_le32(1)) { __u32 hash = le32_to_cpu(BHDR(bs->bh)->h_hash); /* * This must happen under buffer lock for * ext4_xattr_block_set() to reliably detect modified * block */ if (ea_block_cache) { struct mb_cache_entry *oe; oe = mb_cache_entry_delete_or_get(ea_block_cache, hash, bs->bh->b_blocknr); if (oe) { /* * Xattr block is getting reused. Leave * it alone. */ mb_cache_entry_put(ea_block_cache, oe); goto clone_block; } } ea_bdebug(bs->bh, "modifying in-place"); error = ext4_xattr_set_entry(i, s, handle, inode, true /* is_block */); ext4_xattr_block_csum_set(inode, bs->bh); unlock_buffer(bs->bh); if (error == -EFSCORRUPTED) goto bad_block; if (!error) error = ext4_handle_dirty_metadata(handle, inode, bs->bh); if (error) goto cleanup; goto inserted; } clone_block: unlock_buffer(bs->bh); ea_bdebug(bs->bh, "cloning"); s->base = kmemdup(BHDR(bs->bh), bs->bh->b_size, GFP_NOFS); error = -ENOMEM; if (s->base == NULL) goto cleanup; s->first = ENTRY(header(s->base)+1); header(s->base)->h_refcount = cpu_to_le32(1); s->here = ENTRY(s->base + offset); s->end = s->base + bs->bh->b_size; /* * If existing entry points to an xattr inode, we need * to prevent ext4_xattr_set_entry() from decrementing * ref count on it because the reference belongs to the * original block. In this case, make the entry look * like it has an empty value. */ if (!s->not_found && s->here->e_value_inum) { ea_ino = le32_to_cpu(s->here->e_value_inum); error = ext4_xattr_inode_iget(inode, ea_ino, le32_to_cpu(s->here->e_hash), &tmp_inode); if (error) goto cleanup; if (!ext4_test_inode_state(tmp_inode, EXT4_STATE_LUSTRE_EA_INODE)) { /* * Defer quota free call for previous * inode until success is guaranteed. */ old_ea_inode_quota = le32_to_cpu( s->here->e_value_size); } iput(tmp_inode); s->here->e_value_inum = 0; s->here->e_value_size = 0; } } else { /* Allocate a buffer where we construct the new block. */ s->base = kzalloc(sb->s_blocksize, GFP_NOFS); error = -ENOMEM; if (s->base == NULL) goto cleanup; header(s->base)->h_magic = cpu_to_le32(EXT4_XATTR_MAGIC); header(s->base)->h_blocks = cpu_to_le32(1); header(s->base)->h_refcount = cpu_to_le32(1); s->first = ENTRY(header(s->base)+1); s->here = ENTRY(header(s->base)+1); s->end = s->base + sb->s_blocksize; } error = ext4_xattr_set_entry(i, s, handle, inode, true /* is_block */); if (error == -EFSCORRUPTED) goto bad_block; if (error) goto cleanup; if (i->value && s->here->e_value_inum) { /* * A ref count on ea_inode has been taken as part of the call to * ext4_xattr_set_entry() above. We would like to drop this * extra ref but we have to wait until the xattr block is * initialized and has its own ref count on the ea_inode. */ ea_ino = le32_to_cpu(s->here->e_value_inum); error = ext4_xattr_inode_iget(inode, ea_ino, le32_to_cpu(s->here->e_hash), &ea_inode); if (error) { ea_inode = NULL; goto cleanup; } } inserted: if (!IS_LAST_ENTRY(s->first)) { new_bh = ext4_xattr_block_cache_find(inode, header(s->base), &ce); if (new_bh) { /* We found an identical block in the cache. */ if (new_bh == bs->bh) ea_bdebug(new_bh, "keeping"); else { u32 ref; #ifdef EXT4_XATTR_DEBUG WARN_ON_ONCE(dquot_initialize_needed(inode)); #endif /* The old block is released after updating the inode. */ error = dquot_alloc_block(inode, EXT4_C2B(EXT4_SB(sb), 1)); if (error) goto cleanup; BUFFER_TRACE(new_bh, "get_write_access"); error = ext4_journal_get_write_access( handle, sb, new_bh, EXT4_JTR_NONE); if (error) goto cleanup_dquot; lock_buffer(new_bh); /* * We have to be careful about races with * adding references to xattr block. Once we * hold buffer lock xattr block's state is * stable so we can check the additional * reference fits. */ ref = le32_to_cpu(BHDR(new_bh)->h_refcount) + 1; if (ref > EXT4_XATTR_REFCOUNT_MAX) { /* * Undo everything and check mbcache * again. */ unlock_buffer(new_bh); dquot_free_block(inode, EXT4_C2B(EXT4_SB(sb), 1)); brelse(new_bh); mb_cache_entry_put(ea_block_cache, ce); ce = NULL; new_bh = NULL; goto inserted; } BHDR(new_bh)->h_refcount = cpu_to_le32(ref); if (ref == EXT4_XATTR_REFCOUNT_MAX) clear_bit(MBE_REUSABLE_B, &ce->e_flags); ea_bdebug(new_bh, "reusing; refcount now=%d", ref); ext4_xattr_block_csum_set(inode, new_bh); unlock_buffer(new_bh); error = ext4_handle_dirty_metadata(handle, inode, new_bh); if (error) goto cleanup_dquot; } mb_cache_entry_touch(ea_block_cache, ce); mb_cache_entry_put(ea_block_cache, ce); ce = NULL; } else if (bs->bh && s->base == bs->bh->b_data) { /* We were modifying this block in-place. */ ea_bdebug(bs->bh, "keeping this block"); ext4_xattr_block_cache_insert(ea_block_cache, bs->bh); new_bh = bs->bh; get_bh(new_bh); } else { /* We need to allocate a new block */ ext4_fsblk_t goal, block; #ifdef EXT4_XATTR_DEBUG WARN_ON_ONCE(dquot_initialize_needed(inode)); #endif goal = ext4_group_first_block_no(sb, EXT4_I(inode)->i_block_group); block = ext4_new_meta_blocks(handle, inode, goal, 0, NULL, &error); if (error) goto cleanup; ea_idebug(inode, "creating block %llu", (unsigned long long)block); new_bh = sb_getblk(sb, block); if (unlikely(!new_bh)) { error = -ENOMEM; getblk_failed: ext4_free_blocks(handle, inode, NULL, block, 1, EXT4_FREE_BLOCKS_METADATA); goto cleanup; } error = ext4_xattr_inode_inc_ref_all(handle, inode, ENTRY(header(s->base)+1)); if (error) goto getblk_failed; if (ea_inode) { /* Drop the extra ref on ea_inode. */ error = ext4_xattr_inode_dec_ref(handle, ea_inode); if (error) ext4_warning_inode(ea_inode, "dec ref error=%d", error); iput(ea_inode); ea_inode = NULL; } lock_buffer(new_bh); error = ext4_journal_get_create_access(handle, sb, new_bh, EXT4_JTR_NONE); if (error) { unlock_buffer(new_bh); error = -EIO; goto getblk_failed; } memcpy(new_bh->b_data, s->base, new_bh->b_size); ext4_xattr_block_csum_set(inode, new_bh); set_buffer_uptodate(new_bh); unlock_buffer(new_bh); ext4_xattr_block_cache_insert(ea_block_cache, new_bh); error = ext4_handle_dirty_metadata(handle, inode, new_bh); if (error) goto cleanup; } } if (old_ea_inode_quota) ext4_xattr_inode_free_quota(inode, NULL, old_ea_inode_quota); /* Update the inode. */ EXT4_I(inode)->i_file_acl = new_bh ? new_bh->b_blocknr : 0; /* Drop the previous xattr block. */ if (bs->bh && bs->bh != new_bh) { struct ext4_xattr_inode_array *ea_inode_array = NULL; ext4_xattr_release_block(handle, inode, bs->bh, &ea_inode_array, 0 /* extra_credits */); ext4_xattr_inode_array_free(ea_inode_array); } error = 0; cleanup: if (ea_inode) { int error2; error2 = ext4_xattr_inode_dec_ref(handle, ea_inode); if (error2) ext4_warning_inode(ea_inode, "dec ref error=%d", error2); /* If there was an error, revert the quota charge. */ if (error) ext4_xattr_inode_free_quota(inode, ea_inode, i_size_read(ea_inode)); iput(ea_inode); } if (ce) mb_cache_entry_put(ea_block_cache, ce); brelse(new_bh); if (!(bs->bh && s->base == bs->bh->b_data)) kfree(s->base); return error; cleanup_dquot: dquot_free_block(inode, EXT4_C2B(EXT4_SB(sb), 1)); goto cleanup; bad_block: EXT4_ERROR_INODE(inode, "bad block %llu", EXT4_I(inode)->i_file_acl); goto cleanup; #undef header } int ext4_xattr_ibody_find(struct inode *inode, struct ext4_xattr_info *i, struct ext4_xattr_ibody_find *is) { struct ext4_xattr_ibody_header *header; struct ext4_inode *raw_inode; int error; if (!EXT4_INODE_HAS_XATTR_SPACE(inode)) return 0; raw_inode = ext4_raw_inode(&is->iloc); header = IHDR(inode, raw_inode); is->s.base = is->s.first = IFIRST(header); is->s.here = is->s.first; is->s.end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size; if (ext4_test_inode_state(inode, EXT4_STATE_XATTR)) { error = xattr_check_inode(inode, header, is->s.end); if (error) return error; /* Find the named attribute. */ error = xattr_find_entry(inode, &is->s.here, is->s.end, i->name_index, i->name, 0); if (error && error != -ENODATA) return error; is->s.not_found = error; } return 0; } int ext4_xattr_ibody_set(handle_t *handle, struct inode *inode, struct ext4_xattr_info *i, struct ext4_xattr_ibody_find *is) { struct ext4_xattr_ibody_header *header; struct ext4_xattr_search *s = &is->s; int error; if (!EXT4_INODE_HAS_XATTR_SPACE(inode)) return -ENOSPC; error = ext4_xattr_set_entry(i, s, handle, inode, false /* is_block */); if (error) return error; header = IHDR(inode, ext4_raw_inode(&is->iloc)); if (!IS_LAST_ENTRY(s->first)) { header->h_magic = cpu_to_le32(EXT4_XATTR_MAGIC); ext4_set_inode_state(inode, EXT4_STATE_XATTR); } else { header->h_magic = cpu_to_le32(0); ext4_clear_inode_state(inode, EXT4_STATE_XATTR); } return 0; } static int ext4_xattr_value_same(struct ext4_xattr_search *s, struct ext4_xattr_info *i) { void *value; /* When e_value_inum is set the value is stored externally. */ if (s->here->e_value_inum) return 0; if (le32_to_cpu(s->here->e_value_size) != i->value_len) return 0; value = ((void *)s->base) + le16_to_cpu(s->here->e_value_offs); return !memcmp(value, i->value, i->value_len); } static struct buffer_head *ext4_xattr_get_block(struct inode *inode) { struct buffer_head *bh; int error; if (!EXT4_I(inode)->i_file_acl) return NULL; bh = ext4_sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl, REQ_PRIO); if (IS_ERR(bh)) return bh; error = ext4_xattr_check_block(inode, bh); if (error) { brelse(bh); return ERR_PTR(error); } return bh; } /* * ext4_xattr_set_handle() * * Create, replace or remove an extended attribute for this inode. Value * is NULL to remove an existing extended attribute, and non-NULL to * either replace an existing extended attribute, or create a new extended * attribute. The flags XATTR_REPLACE and XATTR_CREATE * specify that an extended attribute must exist and must not exist * previous to the call, respectively. * * Returns 0, or a negative error number on failure. */ int ext4_xattr_set_handle(handle_t *handle, struct inode *inode, int name_index, const char *name, const void *value, size_t value_len, int flags) { struct ext4_xattr_info i = { .name_index = name_index, .name = name, .value = value, .value_len = value_len, .in_inode = 0, }; struct ext4_xattr_ibody_find is = { .s = { .not_found = -ENODATA, }, }; struct ext4_xattr_block_find bs = { .s = { .not_found = -ENODATA, }, }; int no_expand; int error; if (!name) return -EINVAL; if (strlen(name) > 255) return -ERANGE; ext4_write_lock_xattr(inode, &no_expand); /* Check journal credits under write lock. */ if (ext4_handle_valid(handle)) { struct buffer_head *bh; int credits; bh = ext4_xattr_get_block(inode); if (IS_ERR(bh)) { error = PTR_ERR(bh); goto cleanup; } credits = __ext4_xattr_set_credits(inode->i_sb, inode, bh, value_len, flags & XATTR_CREATE); brelse(bh); if (jbd2_handle_buffer_credits(handle) < credits) { error = -ENOSPC; goto cleanup; } WARN_ON_ONCE(!(current->flags & PF_MEMALLOC_NOFS)); } error = ext4_reserve_inode_write(handle, inode, &is.iloc); if (error) goto cleanup; if (ext4_test_inode_state(inode, EXT4_STATE_NEW)) { struct ext4_inode *raw_inode = ext4_raw_inode(&is.iloc); memset(raw_inode, 0, EXT4_SB(inode->i_sb)->s_inode_size); ext4_clear_inode_state(inode, EXT4_STATE_NEW); } error = ext4_xattr_ibody_find(inode, &i, &is); if (error) goto cleanup; if (is.s.not_found) error = ext4_xattr_block_find(inode, &i, &bs); if (error) goto cleanup; if (is.s.not_found && bs.s.not_found) { error = -ENODATA; if (flags & XATTR_REPLACE) goto cleanup; error = 0; if (!value) goto cleanup; } else { error = -EEXIST; if (flags & XATTR_CREATE) goto cleanup; } if (!value) { if (!is.s.not_found) error = ext4_xattr_ibody_set(handle, inode, &i, &is); else if (!bs.s.not_found) error = ext4_xattr_block_set(handle, inode, &i, &bs); } else { error = 0; /* Xattr value did not change? Save us some work and bail out */ if (!is.s.not_found && ext4_xattr_value_same(&is.s, &i)) goto cleanup; if (!bs.s.not_found && ext4_xattr_value_same(&bs.s, &i)) goto cleanup; if (ext4_has_feature_ea_inode(inode->i_sb) && (EXT4_XATTR_SIZE(i.value_len) > EXT4_XATTR_MIN_LARGE_EA_SIZE(inode->i_sb->s_blocksize))) i.in_inode = 1; retry_inode: error = ext4_xattr_ibody_set(handle, inode, &i, &is); if (!error && !bs.s.not_found) { i.value = NULL; error = ext4_xattr_block_set(handle, inode, &i, &bs); } else if (error == -ENOSPC) { if (EXT4_I(inode)->i_file_acl && !bs.s.base) { brelse(bs.bh); bs.bh = NULL; error = ext4_xattr_block_find(inode, &i, &bs); if (error) goto cleanup; } error = ext4_xattr_block_set(handle, inode, &i, &bs); if (!error && !is.s.not_found) { i.value = NULL; error = ext4_xattr_ibody_set(handle, inode, &i, &is); } else if (error == -ENOSPC) { /* * Xattr does not fit in the block, store at * external inode if possible. */ if (ext4_has_feature_ea_inode(inode->i_sb) && i.value_len && !i.in_inode) { i.in_inode = 1; goto retry_inode; } } } } if (!error) { ext4_xattr_update_super_block(handle, inode->i_sb); inode_set_ctime_current(inode); inode_inc_iversion(inode); if (!value) no_expand = 0; error = ext4_mark_iloc_dirty(handle, inode, &is.iloc); /* * The bh is consumed by ext4_mark_iloc_dirty, even with * error != 0. */ is.iloc.bh = NULL; if (IS_SYNC(inode)) ext4_handle_sync(handle); } ext4_fc_mark_ineligible(inode->i_sb, EXT4_FC_REASON_XATTR, handle); cleanup: brelse(is.iloc.bh); brelse(bs.bh); ext4_write_unlock_xattr(inode, &no_expand); return error; } int ext4_xattr_set_credits(struct inode *inode, size_t value_len, bool is_create, int *credits) { struct buffer_head *bh; int err; *credits = 0; if (!EXT4_SB(inode->i_sb)->s_journal) return 0; down_read(&EXT4_I(inode)->xattr_sem); bh = ext4_xattr_get_block(inode); if (IS_ERR(bh)) { err = PTR_ERR(bh); } else { *credits = __ext4_xattr_set_credits(inode->i_sb, inode, bh, value_len, is_create); brelse(bh); err = 0; } up_read(&EXT4_I(inode)->xattr_sem); return err; } /* * ext4_xattr_set() * * Like ext4_xattr_set_handle, but start from an inode. This extended * attribute modification is a filesystem transaction by itself. * * Returns 0, or a negative error number on failure. */ int ext4_xattr_set(struct inode *inode, int name_index, const char *name, const void *value, size_t value_len, int flags) { handle_t *handle; struct super_block *sb = inode->i_sb; int error, retries = 0; int credits; error = dquot_initialize(inode); if (error) return error; retry: error = ext4_xattr_set_credits(inode, value_len, flags & XATTR_CREATE, &credits); if (error) return error; handle = ext4_journal_start(inode, EXT4_HT_XATTR, credits); if (IS_ERR(handle)) { error = PTR_ERR(handle); } else { int error2; error = ext4_xattr_set_handle(handle, inode, name_index, name, value, value_len, flags); error2 = ext4_journal_stop(handle); if (error == -ENOSPC && ext4_should_retry_alloc(sb, &retries)) goto retry; if (error == 0) error = error2; } ext4_fc_mark_ineligible(inode->i_sb, EXT4_FC_REASON_XATTR, NULL); return error; } /* * Shift the EA entries in the inode to create space for the increased * i_extra_isize. */ static void ext4_xattr_shift_entries(struct ext4_xattr_entry *entry, int value_offs_shift, void *to, void *from, size_t n) { struct ext4_xattr_entry *last = entry; int new_offs; /* We always shift xattr headers further thus offsets get lower */ BUG_ON(value_offs_shift > 0); /* Adjust the value offsets of the entries */ for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) { if (!last->e_value_inum && last->e_value_size) { new_offs = le16_to_cpu(last->e_value_offs) + value_offs_shift; last->e_value_offs = cpu_to_le16(new_offs); } } /* Shift the entries by n bytes */ memmove(to, from, n); } /* * Move xattr pointed to by 'entry' from inode into external xattr block */ static int ext4_xattr_move_to_block(handle_t *handle, struct inode *inode, struct ext4_inode *raw_inode, struct ext4_xattr_entry *entry) { struct ext4_xattr_ibody_find *is = NULL; struct ext4_xattr_block_find *bs = NULL; char *buffer = NULL, *b_entry_name = NULL; size_t value_size = le32_to_cpu(entry->e_value_size); struct ext4_xattr_info i = { .value = NULL, .value_len = 0, .name_index = entry->e_name_index, .in_inode = !!entry->e_value_inum, }; struct ext4_xattr_ibody_header *header = IHDR(inode, raw_inode); int needs_kvfree = 0; int error; is = kzalloc(sizeof(struct ext4_xattr_ibody_find), GFP_NOFS); bs = kzalloc(sizeof(struct ext4_xattr_block_find), GFP_NOFS); b_entry_name = kmalloc(entry->e_name_len + 1, GFP_NOFS); if (!is || !bs || !b_entry_name) { error = -ENOMEM; goto out; } is->s.not_found = -ENODATA; bs->s.not_found = -ENODATA; is->iloc.bh = NULL; bs->bh = NULL; /* Save the entry name and the entry value */ if (entry->e_value_inum) { buffer = kvmalloc(value_size, GFP_NOFS); if (!buffer) { error = -ENOMEM; goto out; } needs_kvfree = 1; error = ext4_xattr_inode_get(inode, entry, buffer, value_size); if (error) goto out; } else { size_t value_offs = le16_to_cpu(entry->e_value_offs); buffer = (void *)IFIRST(header) + value_offs; } memcpy(b_entry_name, entry->e_name, entry->e_name_len); b_entry_name[entry->e_name_len] = '\0'; i.name = b_entry_name; error = ext4_get_inode_loc(inode, &is->iloc); if (error) goto out; error = ext4_xattr_ibody_find(inode, &i, is); if (error) goto out; i.value = buffer; i.value_len = value_size; error = ext4_xattr_block_find(inode, &i, bs); if (error) goto out; /* Move ea entry from the inode into the block */ error = ext4_xattr_block_set(handle, inode, &i, bs); if (error) goto out; /* Remove the chosen entry from the inode */ i.value = NULL; i.value_len = 0; error = ext4_xattr_ibody_set(handle, inode, &i, is); out: kfree(b_entry_name); if (needs_kvfree && buffer) kvfree(buffer); if (is) brelse(is->iloc.bh); if (bs) brelse(bs->bh); kfree(is); kfree(bs); return error; } static int ext4_xattr_make_inode_space(handle_t *handle, struct inode *inode, struct ext4_inode *raw_inode, int isize_diff, size_t ifree, size_t bfree, int *total_ino) { struct ext4_xattr_ibody_header *header = IHDR(inode, raw_inode); struct ext4_xattr_entry *small_entry; struct ext4_xattr_entry *entry; struct ext4_xattr_entry *last; unsigned int entry_size; /* EA entry size */ unsigned int total_size; /* EA entry size + value size */ unsigned int min_total_size; int error; while (isize_diff > ifree) { entry = NULL; small_entry = NULL; min_total_size = ~0U; last = IFIRST(header); /* Find the entry best suited to be pushed into EA block */ for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) { /* never move system.data out of the inode */ if ((last->e_name_len == 4) && (last->e_name_index == EXT4_XATTR_INDEX_SYSTEM) && !memcmp(last->e_name, "data", 4)) continue; total_size = EXT4_XATTR_LEN(last->e_name_len); if (!last->e_value_inum) total_size += EXT4_XATTR_SIZE( le32_to_cpu(last->e_value_size)); if (total_size <= bfree && total_size < min_total_size) { if (total_size + ifree < isize_diff) { small_entry = last; } else { entry = last; min_total_size = total_size; } } } if (entry == NULL) { if (small_entry == NULL) return -ENOSPC; entry = small_entry; } entry_size = EXT4_XATTR_LEN(entry->e_name_len); total_size = entry_size; if (!entry->e_value_inum) total_size += EXT4_XATTR_SIZE( le32_to_cpu(entry->e_value_size)); error = ext4_xattr_move_to_block(handle, inode, raw_inode, entry); if (error) return error; *total_ino -= entry_size; ifree += total_size; bfree -= total_size; } return 0; } /* * Expand an inode by new_extra_isize bytes when EAs are present. * Returns 0 on success or negative error number on failure. */ int ext4_expand_extra_isize_ea(struct inode *inode, int new_extra_isize, struct ext4_inode *raw_inode, handle_t *handle) { struct ext4_xattr_ibody_header *header; struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); static unsigned int mnt_count; size_t min_offs; size_t ifree, bfree; int total_ino; void *base, *end; int error = 0, tried_min_extra_isize = 0; int s_min_extra_isize = le16_to_cpu(sbi->s_es->s_min_extra_isize); int isize_diff; /* How much do we need to grow i_extra_isize */ retry: isize_diff = new_extra_isize - EXT4_I(inode)->i_extra_isize; if (EXT4_I(inode)->i_extra_isize >= new_extra_isize) return 0; header = IHDR(inode, raw_inode); /* * Check if enough free space is available in the inode to shift the * entries ahead by new_extra_isize. */ base = IFIRST(header); end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size; min_offs = end - base; total_ino = sizeof(struct ext4_xattr_ibody_header) + sizeof(u32); error = xattr_check_inode(inode, header, end); if (error) goto cleanup; ifree = ext4_xattr_free_space(base, &min_offs, base, &total_ino); if (ifree >= isize_diff) goto shift; /* * Enough free space isn't available in the inode, check if * EA block can hold new_extra_isize bytes. */ if (EXT4_I(inode)->i_file_acl) { struct buffer_head *bh; bh = ext4_sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl, REQ_PRIO); if (IS_ERR(bh)) { error = PTR_ERR(bh); goto cleanup; } error = ext4_xattr_check_block(inode, bh); if (error) { brelse(bh); goto cleanup; } base = BHDR(bh); end = bh->b_data + bh->b_size; min_offs = end - base; bfree = ext4_xattr_free_space(BFIRST(bh), &min_offs, base, NULL); brelse(bh); if (bfree + ifree < isize_diff) { if (!tried_min_extra_isize && s_min_extra_isize) { tried_min_extra_isize++; new_extra_isize = s_min_extra_isize; goto retry; } error = -ENOSPC; goto cleanup; } } else { bfree = inode->i_sb->s_blocksize; } error = ext4_xattr_make_inode_space(handle, inode, raw_inode, isize_diff, ifree, bfree, &total_ino); if (error) { if (error == -ENOSPC && !tried_min_extra_isize && s_min_extra_isize) { tried_min_extra_isize++; new_extra_isize = s_min_extra_isize; goto retry; } goto cleanup; } shift: /* Adjust the offsets and shift the remaining entries ahead */ ext4_xattr_shift_entries(IFIRST(header), EXT4_I(inode)->i_extra_isize - new_extra_isize, (void *)raw_inode + EXT4_GOOD_OLD_INODE_SIZE + new_extra_isize, (void *)header, total_ino); EXT4_I(inode)->i_extra_isize = new_extra_isize; if (ext4_has_inline_data(inode)) error = ext4_find_inline_data_nolock(inode); cleanup: if (error && (mnt_count != le16_to_cpu(sbi->s_es->s_mnt_count))) { ext4_warning(inode->i_sb, "Unable to expand inode %lu. Delete some EAs or run e2fsck.", inode->i_ino); mnt_count = le16_to_cpu(sbi->s_es->s_mnt_count); } return error; } #define EIA_INCR 16 /* must be 2^n */ #define EIA_MASK (EIA_INCR - 1) /* Add the large xattr @inode into @ea_inode_array for deferred iput(). * If @ea_inode_array is new or full it will be grown and the old * contents copied over. */ static int ext4_expand_inode_array(struct ext4_xattr_inode_array **ea_inode_array, struct inode *inode) { if (*ea_inode_array == NULL) { /* * Start with 15 inodes, so it fits into a power-of-two size. * If *ea_inode_array is NULL, this is essentially offsetof() */ (*ea_inode_array) = kmalloc(offsetof(struct ext4_xattr_inode_array, inodes[EIA_MASK]), GFP_NOFS); if (*ea_inode_array == NULL) return -ENOMEM; (*ea_inode_array)->count = 0; } else if (((*ea_inode_array)->count & EIA_MASK) == EIA_MASK) { /* expand the array once all 15 + n * 16 slots are full */ struct ext4_xattr_inode_array *new_array = NULL; int count = (*ea_inode_array)->count; /* if new_array is NULL, this is essentially offsetof() */ new_array = kmalloc( offsetof(struct ext4_xattr_inode_array, inodes[count + EIA_INCR]), GFP_NOFS); if (new_array == NULL) return -ENOMEM; memcpy(new_array, *ea_inode_array, offsetof(struct ext4_xattr_inode_array, inodes[count])); kfree(*ea_inode_array); *ea_inode_array = new_array; } (*ea_inode_array)->inodes[(*ea_inode_array)->count++] = inode; return 0; } /* * ext4_xattr_delete_inode() * * Free extended attribute resources associated with this inode. Traverse * all entries and decrement reference on any xattr inodes associated with this * inode. This is called immediately before an inode is freed. We have exclusive * access to the inode. If an orphan inode is deleted it will also release its * references on xattr block and xattr inodes. */ int ext4_xattr_delete_inode(handle_t *handle, struct inode *inode, struct ext4_xattr_inode_array **ea_inode_array, int extra_credits) { struct buffer_head *bh = NULL; struct ext4_xattr_ibody_header *header; struct ext4_iloc iloc = { .bh = NULL }; struct ext4_xattr_entry *entry; struct inode *ea_inode; int error; error = ext4_journal_ensure_credits(handle, extra_credits, ext4_free_metadata_revoke_credits(inode->i_sb, 1)); if (error < 0) { EXT4_ERROR_INODE(inode, "ensure credits (error %d)", error); goto cleanup; } if (ext4_has_feature_ea_inode(inode->i_sb) && ext4_test_inode_state(inode, EXT4_STATE_XATTR)) { error = ext4_get_inode_loc(inode, &iloc); if (error) { EXT4_ERROR_INODE(inode, "inode loc (error %d)", error); goto cleanup; } error = ext4_journal_get_write_access(handle, inode->i_sb, iloc.bh, EXT4_JTR_NONE); if (error) { EXT4_ERROR_INODE(inode, "write access (error %d)", error); goto cleanup; } header = IHDR(inode, ext4_raw_inode(&iloc)); if (header->h_magic == cpu_to_le32(EXT4_XATTR_MAGIC)) ext4_xattr_inode_dec_ref_all(handle, inode, iloc.bh, IFIRST(header), false /* block_csum */, ea_inode_array, extra_credits, false /* skip_quota */); } if (EXT4_I(inode)->i_file_acl) { bh = ext4_sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl, REQ_PRIO); if (IS_ERR(bh)) { error = PTR_ERR(bh); if (error == -EIO) { EXT4_ERROR_INODE_ERR(inode, EIO, "block %llu read error", EXT4_I(inode)->i_file_acl); } bh = NULL; goto cleanup; } error = ext4_xattr_check_block(inode, bh); if (error) goto cleanup; if (ext4_has_feature_ea_inode(inode->i_sb)) { for (entry = BFIRST(bh); !IS_LAST_ENTRY(entry); entry = EXT4_XATTR_NEXT(entry)) { if (!entry->e_value_inum) continue; error = ext4_xattr_inode_iget(inode, le32_to_cpu(entry->e_value_inum), le32_to_cpu(entry->e_hash), &ea_inode); if (error) continue; ext4_xattr_inode_free_quota(inode, ea_inode, le32_to_cpu(entry->e_value_size)); iput(ea_inode); } } ext4_xattr_release_block(handle, inode, bh, ea_inode_array, extra_credits); /* * Update i_file_acl value in the same transaction that releases * block. */ EXT4_I(inode)->i_file_acl = 0; error = ext4_mark_inode_dirty(handle, inode); if (error) { EXT4_ERROR_INODE(inode, "mark inode dirty (error %d)", error); goto cleanup; } ext4_fc_mark_ineligible(inode->i_sb, EXT4_FC_REASON_XATTR, handle); } error = 0; cleanup: brelse(iloc.bh); brelse(bh); return error; } void ext4_xattr_inode_array_free(struct ext4_xattr_inode_array *ea_inode_array) { int idx; if (ea_inode_array == NULL) return; for (idx = 0; idx < ea_inode_array->count; ++idx) iput(ea_inode_array->inodes[idx]); kfree(ea_inode_array); } /* * ext4_xattr_block_cache_insert() * * Create a new entry in the extended attribute block cache, and insert * it unless such an entry is already in the cache. * * Returns 0, or a negative error number on failure. */ static void ext4_xattr_block_cache_insert(struct mb_cache *ea_block_cache, struct buffer_head *bh) { struct ext4_xattr_header *header = BHDR(bh); __u32 hash = le32_to_cpu(header->h_hash); int reusable = le32_to_cpu(header->h_refcount) < EXT4_XATTR_REFCOUNT_MAX; int error; if (!ea_block_cache) return; error = mb_cache_entry_create(ea_block_cache, GFP_NOFS, hash, bh->b_blocknr, reusable); if (error) { if (error == -EBUSY) ea_bdebug(bh, "already in cache"); } else ea_bdebug(bh, "inserting [%x]", (int)hash); } /* * ext4_xattr_cmp() * * Compare two extended attribute blocks for equality. * * Returns 0 if the blocks are equal, 1 if they differ, and * a negative error number on errors. */ static int ext4_xattr_cmp(struct ext4_xattr_header *header1, struct ext4_xattr_header *header2) { struct ext4_xattr_entry *entry1, *entry2; entry1 = ENTRY(header1+1); entry2 = ENTRY(header2+1); while (!IS_LAST_ENTRY(entry1)) { if (IS_LAST_ENTRY(entry2)) return 1; if (entry1->e_hash != entry2->e_hash || entry1->e_name_index != entry2->e_name_index || entry1->e_name_len != entry2->e_name_len || entry1->e_value_size != entry2->e_value_size || entry1->e_value_inum != entry2->e_value_inum || memcmp(entry1->e_name, entry2->e_name, entry1->e_name_len)) return 1; if (!entry1->e_value_inum && memcmp((char *)header1 + le16_to_cpu(entry1->e_value_offs), (char *)header2 + le16_to_cpu(entry2->e_value_offs), le32_to_cpu(entry1->e_value_size))) return 1; entry1 = EXT4_XATTR_NEXT(entry1); entry2 = EXT4_XATTR_NEXT(entry2); } if (!IS_LAST_ENTRY(entry2)) return 1; return 0; } /* * ext4_xattr_block_cache_find() * * Find an identical extended attribute block. * * Returns a pointer to the block found, or NULL if such a block was * not found or an error occurred. */ static struct buffer_head * ext4_xattr_block_cache_find(struct inode *inode, struct ext4_xattr_header *header, struct mb_cache_entry **pce) { __u32 hash = le32_to_cpu(header->h_hash); struct mb_cache_entry *ce; struct mb_cache *ea_block_cache = EA_BLOCK_CACHE(inode); if (!ea_block_cache) return NULL; if (!header->h_hash) return NULL; /* never share */ ea_idebug(inode, "looking for cached blocks [%x]", (int)hash); ce = mb_cache_entry_find_first(ea_block_cache, hash); while (ce) { struct buffer_head *bh; bh = ext4_sb_bread(inode->i_sb, ce->e_value, REQ_PRIO); if (IS_ERR(bh)) { if (PTR_ERR(bh) == -ENOMEM) return NULL; bh = NULL; EXT4_ERROR_INODE(inode, "block %lu read error", (unsigned long)ce->e_value); } else if (ext4_xattr_cmp(header, BHDR(bh)) == 0) { *pce = ce; return bh; } brelse(bh); ce = mb_cache_entry_find_next(ea_block_cache, ce); } return NULL; } #define NAME_HASH_SHIFT 5 #define VALUE_HASH_SHIFT 16 /* * ext4_xattr_hash_entry() * * Compute the hash of an extended attribute. */ static __le32 ext4_xattr_hash_entry(char *name, size_t name_len, __le32 *value, size_t value_count) { __u32 hash = 0; while (name_len--) { hash = (hash << NAME_HASH_SHIFT) ^ (hash >> (8*sizeof(hash) - NAME_HASH_SHIFT)) ^ (unsigned char)*name++; } while (value_count--) { hash = (hash << VALUE_HASH_SHIFT) ^ (hash >> (8*sizeof(hash) - VALUE_HASH_SHIFT)) ^ le32_to_cpu(*value++); } return cpu_to_le32(hash); } /* * ext4_xattr_hash_entry_signed() * * Compute the hash of an extended attribute incorrectly. */ static __le32 ext4_xattr_hash_entry_signed(char *name, size_t name_len, __le32 *value, size_t value_count) { __u32 hash = 0; while (name_len--) { hash = (hash << NAME_HASH_SHIFT) ^ (hash >> (8*sizeof(hash) - NAME_HASH_SHIFT)) ^ (signed char)*name++; } while (value_count--) { hash = (hash << VALUE_HASH_SHIFT) ^ (hash >> (8*sizeof(hash) - VALUE_HASH_SHIFT)) ^ le32_to_cpu(*value++); } return cpu_to_le32(hash); } #undef NAME_HASH_SHIFT #undef VALUE_HASH_SHIFT #define BLOCK_HASH_SHIFT 16 /* * ext4_xattr_rehash() * * Re-compute the extended attribute hash value after an entry has changed. */ static void ext4_xattr_rehash(struct ext4_xattr_header *header) { struct ext4_xattr_entry *here; __u32 hash = 0; here = ENTRY(header+1); while (!IS_LAST_ENTRY(here)) { if (!here->e_hash) { /* Block is not shared if an entry's hash value == 0 */ hash = 0; break; } hash = (hash << BLOCK_HASH_SHIFT) ^ (hash >> (8*sizeof(hash) - BLOCK_HASH_SHIFT)) ^ le32_to_cpu(here->e_hash); here = EXT4_XATTR_NEXT(here); } header->h_hash = cpu_to_le32(hash); } #undef BLOCK_HASH_SHIFT #define HASH_BUCKET_BITS 10 struct mb_cache * ext4_xattr_create_cache(void) { return mb_cache_create(HASH_BUCKET_BITS); } void ext4_xattr_destroy_cache(struct mb_cache *cache) { if (cache) mb_cache_destroy(cache); }
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