2024-03-27 08:56:03

by Zhiguo Niu

Subject: [PATCH V3] f2fs: fix to adjust appropirate defragment pg_end

A length that exceeds the real size of the inode may be
specified from user, although these out-of-range areas
are not mapped, but they still need to be check in
while loop, which is unnecessary.

Signed-off-by: Zhiguo Niu <[email protected]>
---
v3: adjust code positions according to Chao's suggestions
v2: check i_size within inode lock according to Chao's suggestions
---
---
fs/f2fs/file.c | 12 +++++++-----
1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index bc190d5..9908017 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -2627,12 +2627,13 @@ static int f2fs_defragment_range(struct f2fs_sb_info *sbi,
bool fragmented = false;
int err;

- pg_start = range->start >> PAGE_SHIFT;
- pg_end = (range->start + range->len) >> PAGE_SHIFT;
-
f2fs_balance_fs(sbi, true);

inode_lock(inode);
+ pg_start = range->start >> PAGE_SHIFT;
+ pg_end = min_t(pgoff_t,
+ (range->start + range->len) >> PAGE_SHIFT,
+ DIV_ROUND_UP(i_size_read(inode), PAGE_SIZE));

if (is_inode_flag_set(inode, FI_COMPRESS_RELEASED)) {
err = -EINVAL;
@@ -2647,8 +2648,9 @@ static int f2fs_defragment_range(struct f2fs_sb_info *sbi,
}

/* writeback all dirty pages in the range */
- err = filemap_write_and_wait_range(inode->i_mapping, range->start,
- range->start + range->len - 1);
+ err = filemap_write_and_wait_range(inode->i_mapping,
+ pg_start << PAGE_SHIFT,
+ pg_end << PAGE_SHIFT - 1);
if (err)
goto out;

--
1.9.1

2024-03-29 06:12:11

by Chao Yu

Subject: Re: [PATCH V3] f2fs: fix to adjust appropirate defragment pg_end

On 2024/3/27 16:53, Zhiguo Niu wrote:
> A length that exceeds the real size of the inode may be
> specified from user, although these out-of-range areas
> are not mapped, but they still need to be check in
> while loop, which is unnecessary.
>
> Signed-off-by: Zhiguo Niu <[email protected]>

Reviewed-by: Chao Yu <[email protected]>

Thanks,