diff options
| author | Gao Xiang <hsiangkao@linux.alibaba.com> | 2026-03-24 23:54:07 +0800 |
|---|---|---|
| committer | Gao Xiang <hsiangkao@linux.alibaba.com> | 2026-03-25 10:40:02 +0800 |
| commit | 2f0407ed923b7eb363424033fc12fe253da139c4 (patch) | |
| tree | 1ac73966f9946ce2a26aeb89079f9ad4dd549169 /fs | |
| parent | 938c418422c4b08523ae39aebbd828428dcfefd2 (diff) | |
erofs: fix .fadvise() for page cache sharing
Currently, .fadvise() doesn't work well if page cache sharing is on
since shared inodes belong to a pseudo fs generated with init_pseudo(),
and sb->s_bdi is the default one &noop_backing_dev_info.
Then, generic_fadvise() will just behave as a no-op if sb->s_bdi is
&noop_backing_dev_info, but as the bdev fs (the bdev fs changes
inode_to_bdi() instead), it's actually NOT a pure memfs.
Let's generate a real bdi for erofs_ishare_mnt instead.
Fixes: d86d7817c042 ("erofs: implement .fadvise for page cache share")
Reviewed-by: Hongbo Li <lihongbo22@huawei.com>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/erofs/ishare.c | 15 |
1 files changed, 13 insertions, 2 deletions
diff --git a/fs/erofs/ishare.c b/fs/erofs/ishare.c index 829d50d5c717..ec433bacc592 100644 --- a/fs/erofs/ishare.c +++ b/fs/erofs/ishare.c @@ -200,8 +200,19 @@ struct inode *erofs_real_inode(struct inode *inode, bool *need_iput) int __init erofs_init_ishare(void) { - erofs_ishare_mnt = kern_mount(&erofs_anon_fs_type); - return PTR_ERR_OR_ZERO(erofs_ishare_mnt); + struct vfsmount *mnt; + int ret; + + mnt = kern_mount(&erofs_anon_fs_type); + if (IS_ERR(mnt)) + return PTR_ERR(mnt); + /* generic_fadvise() doesn't work if s_bdi == &noop_backing_dev_info */ + ret = super_setup_bdi(mnt->mnt_sb); + if (ret) + kern_unmount(mnt); + else + erofs_ishare_mnt = mnt; + return ret; } void erofs_exit_ishare(void) |