cregit-Linux how code gets into the kernel

Release 4.10 fs/jffs2/file.c

Directory: fs/jffs2
/*
 * JFFS2 -- Journalling Flash File System, Version 2.
 *
 * Copyright © 2001-2007 Red Hat, Inc.
 * Copyright © 2004-2010 David Woodhouse <dwmw2@infradead.org>
 *
 * Created by David Woodhouse <dwmw2@infradead.org>
 *
 * For licensing information, see the file 'LICENCE' in this directory.
 *
 */


#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/kernel.h>
#include <linux/fs.h>
#include <linux/time.h>
#include <linux/pagemap.h>
#include <linux/highmem.h>
#include <linux/crc32.h>
#include <linux/jffs2.h>
#include "nodelist.h"

static int jffs2_write_end(struct file *filp, struct address_space *mapping,
			loff_t pos, unsigned len, unsigned copied,
			struct page *pg, void *fsdata);
static int jffs2_write_begin(struct file *filp, struct address_space *mapping,
			loff_t pos, unsigned len, unsigned flags,
			struct page **pagep, void **fsdata);
static int jffs2_readpage (struct file *filp, struct page *pg);


int jffs2_fsync(struct file *filp, loff_t start, loff_t end, int datasync) { struct inode *inode = filp->f_mapping->host; struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb); int ret; ret = filemap_write_and_wait_range(inode->i_mapping, start, end); if (ret) return ret; inode_lock(inode); /* Trigger GC to flush any pending writes for this inode */ jffs2_flush_wbuf_gc(c, inode->i_ino); inode_unlock(inode); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
josef bacikjosef bacik3742.05%114.29%
linus torvaldslinus torvalds2730.68%114.29%
david woodhousedavid woodhouse1820.45%342.86%
christoph hellwigchristoph hellwig44.55%114.29%
al viroal viro22.27%114.29%
Total88100.00%7100.00%

const struct file_operations jffs2_file_operations = { .llseek = generic_file_llseek, .open = generic_file_open, .read_iter = generic_file_read_iter, .write_iter = generic_file_write_iter, .unlocked_ioctl=jffs2_ioctl, .mmap = generic_file_readonly_mmap, .fsync = jffs2_fsync, .splice_read = generic_file_splice_read, }; /* jffs2_file_inode_operations */ const struct inode_operations jffs2_file_inode_operations = { .get_acl = jffs2_get_acl, .set_acl = jffs2_set_acl, .setattr = jffs2_setattr, .listxattr = jffs2_listxattr, }; const struct address_space_operations jffs2_file_address_operations = { .readpage = jffs2_readpage, .write_begin = jffs2_write_begin, .write_end = jffs2_write_end, };
static int jffs2_do_readpage_nolock (struct inode *inode, struct page *pg) { struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode); struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb); unsigned char *pg_buf; int ret; jffs2_dbg(2, "%s(): ino #%lu, page at offset 0x%lx\n", __func__, inode->i_ino, pg->index << PAGE_SHIFT); BUG_ON(!PageLocked(pg)); pg_buf = kmap(pg); /* FIXME: Can kmap fail? */ ret = jffs2_read_inode_range(c, f, pg_buf, pg->index << PAGE_SHIFT, PAGE_SIZE); if (ret) { ClearPageUptodate(pg); SetPageError(pg); } else { SetPageUptodate(pg); ClearPageError(pg); } flush_dcache_page(pg); kunmap(pg); jffs2_dbg(2, "readpage finished\n"); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
linus torvaldslinus torvalds9865.33%114.29%
david woodhousedavid woodhouse3624.00%114.29%
joe perchesjoe perches96.00%114.29%
kirill a. shutemovkirill a. shutemov32.00%114.29%
matt mackallmatt mackall21.33%114.29%
adrian bunkadrian bunk10.67%114.29%
anders grafstromanders grafstrom10.67%114.29%
Total150100.00%7100.00%


int jffs2_do_readpage_unlock(struct inode *inode, struct page *pg) { int ret = jffs2_do_readpage_nolock(inode, pg); unlock_page(pg); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
linus torvaldslinus torvalds3296.97%150.00%
andrew mortonandrew morton13.03%150.00%
Total33100.00%2100.00%


static int jffs2_readpage (struct file *filp, struct page *pg) { struct jffs2_inode_info *f = JFFS2_INODE_INFO(pg->mapping->host); int ret; mutex_lock(&f->sem); ret = jffs2_do_readpage_unlock(pg->mapping->host, pg); mutex_unlock(&f->sem); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
linus torvaldslinus torvalds5686.15%125.00%
david woodhousedavid woodhouse812.31%250.00%
adrian bunkadrian bunk11.54%125.00%
Total65100.00%4100.00%


static int jffs2_write_begin(struct file *filp, struct address_space *mapping, loff_t pos, unsigned len, unsigned flags, struct page **pagep, void **fsdata) { struct page *pg; struct inode *inode = mapping->host; struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode); pgoff_t index = pos >> PAGE_SHIFT; uint32_t pageofs = index << PAGE_SHIFT; int ret = 0; pg = grab_cache_page_write_begin(mapping, index, flags); if (!pg) return -ENOMEM; *pagep = pg; jffs2_dbg(1, "%s()\n", __func__); if (pageofs > inode->i_size) { /* Make new hole frag from old EOF to new page */ struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb); struct jffs2_raw_inode ri; struct jffs2_full_dnode *fn; uint32_t alloc_len; jffs2_dbg(1, "Writing new hole frag 0x%x-0x%x between current EOF and new page\n", (unsigned int)inode->i_size, pageofs); ret = jffs2_reserve_space(c, sizeof(ri), &alloc_len, ALLOC_NORMAL, JFFS2_SUMMARY_INODE_SIZE); if (ret) goto out_page; mutex_lock(&f->sem); memset(&ri, 0, sizeof(ri)); ri.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK); ri.nodetype = cpu_to_je16(JFFS2_NODETYPE_INODE); ri.totlen = cpu_to_je32(sizeof(ri)); ri.hdr_crc = cpu_to_je32(crc32(0, &ri, sizeof(struct jffs2_unknown_node)-4)); ri.ino = cpu_to_je32(f->inocache->ino); ri.version = cpu_to_je32(++f->highest_version); ri.mode = cpu_to_jemode(inode->i_mode); ri.uid = cpu_to_je16(i_uid_read(inode)); ri.gid = cpu_to_je16(i_gid_read(inode)); ri.isize = cpu_to_je32(max((uint32_t)inode->i_size, pageofs)); ri.atime = ri.ctime = ri.mtime = cpu_to_je32(get_seconds()); ri.offset = cpu_to_je32(inode->i_size); ri.dsize = cpu_to_je32(pageofs - inode->i_size); ri.csize = cpu_to_je32(0); ri.compr = JFFS2_COMPR_ZERO; ri.node_crc = cpu_to_je32(crc32(0, &ri, sizeof(ri)-8)); ri.data_crc = cpu_to_je32(0); fn = jffs2_write_dnode(c, f, &ri, NULL, 0, ALLOC_NORMAL); if (IS_ERR(fn)) { ret = PTR_ERR(fn); jffs2_complete_reservation(c); mutex_unlock(&f->sem); goto out_page; } ret = jffs2_add_full_dnode_to_inode(c, f, fn); if (f->metadata) { jffs2_mark_node_obsolete(c, f->metadata->raw); jffs2_free_full_dnode(f->metadata); f->metadata = NULL; } if (ret) { jffs2_dbg(1, "Eep. add_full_dnode_to_inode() failed in write_begin, returned %d\n", ret); jffs2_mark_node_obsolete(c, fn->raw); jffs2_free_full_dnode(fn); jffs2_complete_reservation(c); mutex_unlock(&f->sem); goto out_page; } jffs2_complete_reservation(c); inode->i_size = pageofs; mutex_unlock(&f->sem); } /* * Read in the page if it wasn't already present. Cannot optimize away * the whole page write case until jffs2_write_end can handle the * case of a short-copy. */ if (!PageUptodate(pg)) { mutex_lock(&f->sem); ret = jffs2_do_readpage_nolock(inode, pg); mutex_unlock(&f->sem); if (ret) goto out_page; } jffs2_dbg(1, "end write_begin(). pg->flags %lx\n", pg->flags); return ret; out_page: unlock_page(pg); put_page(pg); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
linus torvaldslinus torvalds36555.22%211.11%
thomas betkerthomas betker11517.40%211.11%
david woodhousedavid woodhouse7911.95%527.78%
nick pigginnick piggin7811.80%211.11%
joe perchesjoe perches91.36%15.56%
eric w. biedermaneric w. biederman60.91%15.56%
kirill a. shutemovkirill a. shutemov30.45%15.56%
alexey korolevalexey korolev20.30%15.56%
andi kleenandi kleen20.30%15.56%
andrew mortonandrew morton10.15%15.56%
adrian bunkadrian bunk10.15%15.56%
Total661100.00%18100.00%


static int jffs2_write_end(struct file *filp, struct address_space *mapping, loff_t pos, unsigned len, unsigned copied, struct page *pg, void *fsdata) { /* Actually commit the write from the page cache page we're looking at. * For now, we write the full page out each time. It sucks, but it's simple */ struct inode *inode = mapping->host; struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode); struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb); struct jffs2_raw_inode *ri; unsigned start = pos & (PAGE_SIZE - 1); unsigned end = start + copied; unsigned aligned_start = start & ~3; int ret = 0; uint32_t writtenlen = 0; jffs2_dbg(1, "%s(): ino #%lu, page at 0x%lx, range %d-%d, flags %lx\n", __func__, inode->i_ino, pg->index << PAGE_SHIFT, start, end, pg->flags); /* We need to avoid deadlock with page_cache_read() in jffs2_garbage_collect_pass(). So the page must be up to date to prevent page_cache_read() from trying to re-lock it. */ BUG_ON(!PageUptodate(pg)); if (end == PAGE_SIZE) { /* When writing out the end of a page, write out the _whole_ page. This helps to reduce the number of nodes in files which have many short writes, like syslog files. */ aligned_start = 0; } ri = jffs2_alloc_raw_inode(); if (!ri) { jffs2_dbg(1, "%s(): Allocation of raw inode failed\n", __func__); unlock_page(pg); put_page(pg); return -ENOMEM; } /* Set the fields that the generic jffs2_write_inode_range() code can't find */ ri->ino = cpu_to_je32(inode->i_ino); ri->mode = cpu_to_jemode(inode->i_mode); ri->uid = cpu_to_je16(i_uid_read(inode)); ri->gid = cpu_to_je16(i_gid_read(inode)); ri->isize = cpu_to_je32((uint32_t)inode->i_size); ri->atime = ri->ctime = ri->mtime = cpu_to_je32(get_seconds()); /* In 2.4, it was already kmapped by generic_file_write(). Doesn't hurt to do it again. The alternative is ifdefs, which are ugly. */ kmap(pg); ret = jffs2_write_inode_range(c, f, ri, page_address(pg) + aligned_start, (pg->index << PAGE_SHIFT) + aligned_start, end - aligned_start, &writtenlen); kunmap(pg); if (ret) { /* There was an error writing. */ SetPageError(pg); } /* Adjust writtenlen for the padding we did, so we don't confuse our caller */ writtenlen -= min(writtenlen, (start - aligned_start)); if (writtenlen) { if (inode->i_size < pos + writtenlen) { inode->i_size = pos + writtenlen; inode->i_blocks = (inode->i_size + 511) >> 9; inode->i_ctime = inode->i_mtime = ITIME(je32_to_cpu(ri->ctime)); } } jffs2_free_raw_inode(ri); if (start+writtenlen < end) { /* generic_file_write has written more to the page cache than we've actually written to the medium. Mark the page !Uptodate so that it gets reread */ jffs2_dbg(1, "%s(): Not all bytes written. Marking page !uptodate\n", __func__); SetPageError(pg); ClearPageUptodate(pg); } jffs2_dbg(1, "%s() returning %d\n", __func__, writtenlen > 0 ? writtenlen : ret); unlock_page(pg); put_page(pg); return writtenlen > 0 ? writtenlen : ret; }

Contributors

PersonTokensPropCommitsCommitProp
linus torvaldslinus torvalds20443.22%15.88%
david woodhousedavid woodhouse13729.03%635.29%
nick pigginnick piggin7816.53%211.76%
joe perchesjoe perches245.08%15.88%
andrew mortonandrew morton102.12%15.88%
eric w. biedermaneric w. biederman61.27%15.88%
kirill a. shutemovkirill a. shutemov61.27%15.88%
andi kleenandi kleen30.64%15.88%
todd poynortodd poynor20.42%15.88%
thomas gleixnerthomas gleixner10.21%15.88%
adrian bunkadrian bunk10.21%15.88%
Total472100.00%17100.00%


Overall Contributors

PersonTokensPropCommitsCommitProp
linus torvaldslinus torvalds80948.13%36.52%
david woodhousedavid woodhouse33619.99%1021.74%
nick pigginnick piggin19711.72%36.52%
thomas betkerthomas betker1156.84%24.35%
adrian bunkadrian bunk513.03%12.17%
joe perchesjoe perches492.91%24.35%
josef bacikjosef bacik372.20%12.17%
andrew mortonandrew morton150.89%24.35%
kirill a. shutemovkirill a. shutemov120.71%12.17%
eric w. biedermaneric w. biederman120.71%12.17%
christoph hellwigchristoph hellwig120.71%48.70%
kaigai koheikaigai kohei80.48%12.17%
al viroal viro60.36%36.52%
andi kleenandi kleen50.30%12.17%
jens axboejens axboe30.18%12.17%
arjan van de venarjan van de ven20.12%24.35%
todd poynortodd poynor20.12%12.17%
badari pulavartybadari pulavarty20.12%12.17%
matt mackallmatt mackall20.12%12.17%
alexey korolevalexey korolev20.12%12.17%
andreas gruenbacherandreas gruenbacher10.06%12.17%
stoyan gaydarovstoyan gaydarov10.06%12.17%
anders grafstromanders grafstrom10.06%12.17%
thomas gleixnerthomas gleixner10.06%12.17%
Total1681100.00%46100.00%
Directory: fs/jffs2
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