diff options
| author | Rajeev Mishra <rajeevm@hpe.com> | 2025-08-18 18:48:21 +0000 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2025-08-18 13:10:35 -0600 |
| commit | 47b71abd58461a67cae71d2f2a9d44379e4e2fcf (patch) | |
| tree | aeb6c4c30fecf14adda0ba23a4061feb503966a2 | |
| parent | 8aa5a3b68ad144da49a3d17f165e6561255e3529 (diff) | |
loop: use vfs_getattr_nosec for accurate file size
Use vfs_getattr_nosec() in lo_calculate_size() for getting the file
size, rather than just read the cached inode size via i_size_read().
This provides better results than cached inode data, particularly for
network filesystems where metadata may be stale.
Signed-off-by: Rajeev Mishra <rajeevm@hpe.com>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20250818184821.115033-3-rajeevm@hpe.com
[axboe: massage commit message]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
| -rw-r--r-- | drivers/block/loop.c | 15 |
1 files changed, 13 insertions, 2 deletions
diff --git a/drivers/block/loop.c b/drivers/block/loop.c index 0e1b9eb9db10..57263c273f0f 100644 --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -139,9 +139,20 @@ static int part_shift; static loff_t lo_calculate_size(struct loop_device *lo, struct file *file) { + struct kstat stat; loff_t loopsize; - /* Compute loopsize in bytes */ - loopsize = i_size_read(file->f_mapping->host); + int ret; + + /* + * Get the accurate file size. This provides better results than + * cached inode data, particularly for network filesystems where + * metadata may be stale. + */ + ret = vfs_getattr_nosec(&file->f_path, &stat, STATX_SIZE, 0); + if (ret) + return 0; + + loopsize = stat.size; if (lo->lo_offset > 0) loopsize -= lo->lo_offset; /* offset is beyond i_size, weird but possible */ |