diff options
| author | NeilBrown <neil@brown.name> | 2025-11-13 11:18:28 +1100 |
|---|---|---|
| committer | Christian Brauner <brauner@kernel.org> | 2025-11-14 13:15:56 +0100 |
| commit | bd6ede8a06e89ca5a94a8b51cea792705d1b8ca2 (patch) | |
| tree | 0b3d4cfbecbc7886a04e1cc2926b3a19209d155f /fs/nfsd/vfs.c | |
| parent | 7ab96df840e60eb933abfe65fc5fe44e72f16dc0 (diff) | |
VFS/nfsd/cachefiles/ovl: introduce start_removing() and end_removing()
start_removing() is similar to start_creating() but will only return a
positive dentry with the expectation that it will be removed. This is
used by nfsd, cachefiles, and overlayfs. They are changed to also use
end_removing() to terminate the action begun by start_removing(). This
is a simple alias for end_dirop().
Apart from changes to the error paths, as we no longer need to unlock on
a lookup error, an effect on callers is that they don't need to test if
the found dentry is positive or negative - they can be sure it is
positive.
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: NeilBrown <neil@brown.name>
Link: https://patch.msgid.link/20251113002050.676694-6-neilb@ownmail.net
Tested-by: syzbot@syzkaller.appspotmail.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
Diffstat (limited to 'fs/nfsd/vfs.c')
| -rw-r--r-- | fs/nfsd/vfs.c | 26 |
1 files changed, 10 insertions, 16 deletions
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c index 4efd3688e081..cd64ffe12e0b 100644 --- a/fs/nfsd/vfs.c +++ b/fs/nfsd/vfs.c @@ -2044,7 +2044,7 @@ nfsd_unlink(struct svc_rqst *rqstp, struct svc_fh *fhp, int type, { struct dentry *dentry, *rdentry; struct inode *dirp; - struct inode *rinode; + struct inode *rinode = NULL; __be32 err; int host_err; @@ -2063,24 +2063,21 @@ nfsd_unlink(struct svc_rqst *rqstp, struct svc_fh *fhp, int type, dentry = fhp->fh_dentry; dirp = d_inode(dentry); - inode_lock_nested(dirp, I_MUTEX_PARENT); - rdentry = lookup_one(&nop_mnt_idmap, &QSTR_LEN(fname, flen), dentry); + rdentry = start_removing(&nop_mnt_idmap, dentry, &QSTR_LEN(fname, flen)); + host_err = PTR_ERR(rdentry); if (IS_ERR(rdentry)) - goto out_unlock; + goto out_drop_write; - if (d_really_is_negative(rdentry)) { - dput(rdentry); - host_err = -ENOENT; - goto out_unlock; - } - rinode = d_inode(rdentry); err = fh_fill_pre_attrs(fhp); if (err != nfs_ok) goto out_unlock; + rinode = d_inode(rdentry); + /* Prevent truncation until after locks dropped */ ihold(rinode); + if (!type) type = d_inode(rdentry)->i_mode & S_IFMT; @@ -2102,10 +2099,10 @@ nfsd_unlink(struct svc_rqst *rqstp, struct svc_fh *fhp, int type, } fh_fill_post_attrs(fhp); - inode_unlock(dirp); - if (!host_err) +out_unlock: + end_removing(rdentry); + if (!err && !host_err) host_err = commit_metadata(fhp); - dput(rdentry); iput(rinode); /* truncate the inode here */ out_drop_write: @@ -2123,9 +2120,6 @@ out_nfserr: } out: return err != nfs_ok ? err : nfserrno(host_err); -out_unlock: - inode_unlock(dirp); - goto out_drop_write; } /* |