6.6-stable review patch. If anyone has any objections, please let me know.
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From: Chao Yu chao@kernel.org
[ Upstream commit 1a0bd289a5db1df8df8fab949633a0b8d3f235ee ]
Case #1: SQLite App GC Thread Kworker Shrinker - f2fs_ioc_start_atomic_write
- f2fs_ioc_commit_atomic_write - f2fs_commit_atomic_write - filemap_write_and_wait_range : write atomic_file's data to cow_inode echo 3 > drop_caches to drop atomic_file's cache. - f2fs_gc - gc_data_segment - move_data_page - set_page_dirty
- writepages - f2fs_do_write_data_page : overwrite atomic_file's data to cow_inode - f2fs_down_write(&fi->i_gc_rwsem[WRITE]) - __f2fs_commit_atomic_write - f2fs_up_write(&fi->i_gc_rwsem[WRITE])
Case #2: SQLite App GC Thread Kworker - f2fs_ioc_start_atomic_write
- __writeback_single_inode - do_writepages - f2fs_write_cache_pages - f2fs_write_single_data_page - f2fs_do_write_data_page : write atomic_file's data to cow_inode - f2fs_gc - gc_data_segment - move_data_page - set_page_dirty
- writepages - f2fs_do_write_data_page : overwrite atomic_file's data to cow_inode - f2fs_ioc_commit_atomic_write
In above cases racing in between atomic_write and GC, previous data in atomic_file may be overwrited to cow_file, result in data corruption.
This patch introduces PAGE_PRIVATE_ATOMIC_WRITE bit flag in page.private, and use it to indicate that there is last dirty data in atomic file, and the data should be writebacked into cow_file, if the flag is not tagged in page, we should never write data across files.
Fixes: 3db1de0e582c ("f2fs: change the current atomic write way") Cc: Daeho Jeong daehojeong@google.com Signed-off-by: Chao Yu chao@kernel.org Signed-off-by: Jaegeuk Kim jaegeuk@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- fs/f2fs/data.c | 10 +++++++++- fs/f2fs/f2fs.h | 8 +++++++- 2 files changed, 16 insertions(+), 2 deletions(-)
diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c index 84fc87018180f..d54644d386842 100644 --- a/fs/f2fs/data.c +++ b/fs/f2fs/data.c @@ -2623,10 +2623,13 @@ int f2fs_do_write_data_page(struct f2fs_io_info *fio) struct dnode_of_data dn; struct node_info ni; bool ipu_force = false; + bool atomic_commit; int err = 0;
/* Use COW inode to make dnode_of_data for atomic write */ - if (f2fs_is_atomic_file(inode)) + atomic_commit = f2fs_is_atomic_file(inode) && + page_private_atomic(fio->page); + if (atomic_commit) set_new_dnode(&dn, F2FS_I(inode)->cow_inode, NULL, NULL, 0); else set_new_dnode(&dn, inode, NULL, NULL, 0); @@ -2730,6 +2733,8 @@ int f2fs_do_write_data_page(struct f2fs_io_info *fio) f2fs_outplace_write_data(&dn, fio); trace_f2fs_do_write_data_page(page, OPU); set_inode_flag(inode, FI_APPEND_WRITE); + if (atomic_commit) + clear_page_private_atomic(page); out_writepage: f2fs_put_dnode(&dn); out: @@ -3700,6 +3705,9 @@ static int f2fs_write_end(struct file *file,
set_page_dirty(page);
+ if (f2fs_is_atomic_file(inode)) + set_page_private_atomic(page); + if (pos + copied > i_size_read(inode) && !f2fs_verity_in_progress(inode)) { f2fs_i_size_write(inode, pos + copied); diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h index 6371b295fba68..15780e467a64b 100644 --- a/fs/f2fs/f2fs.h +++ b/fs/f2fs/f2fs.h @@ -1411,7 +1411,8 @@ static inline void f2fs_clear_bit(unsigned int nr, char *addr); * bit 1 PAGE_PRIVATE_ONGOING_MIGRATION * bit 2 PAGE_PRIVATE_INLINE_INODE * bit 3 PAGE_PRIVATE_REF_RESOURCE - * bit 4- f2fs private data + * bit 4 PAGE_PRIVATE_ATOMIC_WRITE + * bit 5- f2fs private data * * Layout B: lowest bit should be 0 * page.private is a wrapped pointer. @@ -1421,6 +1422,7 @@ enum { PAGE_PRIVATE_ONGOING_MIGRATION, /* data page which is on-going migrating */ PAGE_PRIVATE_INLINE_INODE, /* inode page contains inline data */ PAGE_PRIVATE_REF_RESOURCE, /* dirty page has referenced resources */ + PAGE_PRIVATE_ATOMIC_WRITE, /* data page from atomic write path */ PAGE_PRIVATE_MAX };
@@ -2386,14 +2388,17 @@ static inline void clear_page_private_##name(struct page *page) \ PAGE_PRIVATE_GET_FUNC(nonpointer, NOT_POINTER); PAGE_PRIVATE_GET_FUNC(inline, INLINE_INODE); PAGE_PRIVATE_GET_FUNC(gcing, ONGOING_MIGRATION); +PAGE_PRIVATE_GET_FUNC(atomic, ATOMIC_WRITE);
PAGE_PRIVATE_SET_FUNC(reference, REF_RESOURCE); PAGE_PRIVATE_SET_FUNC(inline, INLINE_INODE); PAGE_PRIVATE_SET_FUNC(gcing, ONGOING_MIGRATION); +PAGE_PRIVATE_SET_FUNC(atomic, ATOMIC_WRITE);
PAGE_PRIVATE_CLEAR_FUNC(reference, REF_RESOURCE); PAGE_PRIVATE_CLEAR_FUNC(inline, INLINE_INODE); PAGE_PRIVATE_CLEAR_FUNC(gcing, ONGOING_MIGRATION); +PAGE_PRIVATE_CLEAR_FUNC(atomic, ATOMIC_WRITE);
static inline unsigned long get_page_private_data(struct page *page) { @@ -2425,6 +2430,7 @@ static inline void clear_page_private_all(struct page *page) clear_page_private_reference(page); clear_page_private_gcing(page); clear_page_private_inline(page); + clear_page_private_atomic(page);
f2fs_bug_on(F2FS_P_SB(page), page_private(page)); }