whiterose

linux unikernel
Log | Files | Refs | README | LICENSE | git clone https://git.ne02ptzero.me/git/whiterose

commit 4ba9628fe5bf90e0125dbec847a0cf4f5553de14
parent 06999fd59277afef07638453c695a500eb2a93c0
Author: Linus Torvalds <torvalds@linux-foundation.org>
Date:   Thu, 25 Oct 2018 12:55:31 -0700

Merge branch 'work.lookup' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull more ->lookup() cleanups from Al Viro:
 "Some ->lookup() instances are still overcomplicating the life
  for themselves, open-coding the stuff that would be handled by
  d_splice_alias() just fine.

  Simplify a couple of such cases caught this cycle and document
  d_splice_alias() intended use"

* 'work.lookup' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  Document d_splice_alias() calling conventions for ->lookup() users.
  simplify btrfs_lookup()
  clean erofs_lookup()

Diffstat:
MDocumentation/filesystems/porting | 11+++++++++++
Mdrivers/staging/erofs/namei.c | 19+++++++------------
Mfs/btrfs/inode.c | 12+++---------
3 files changed, 21 insertions(+), 21 deletions(-)

diff --git a/Documentation/filesystems/porting b/Documentation/filesystems/porting @@ -622,3 +622,14 @@ in your dentry operations instead. alloc_file_clone(file, flags, ops) does not affect any caller's references. On success you get a new struct file sharing the mount/dentry with the original, on failure - ERR_PTR(). +-- +[recommended] + ->lookup() instances doing an equivalent of + if (IS_ERR(inode)) + return ERR_CAST(inode); + return d_splice_alias(inode, dentry); + don't need to bother with the check - d_splice_alias() will do the + right thing when given ERR_PTR(...) as inode. Moreover, passing NULL + inode to d_splice_alias() will also do the right thing (equivalent of + d_add(dentry, NULL); return NULL;), so that kind of special cases + also doesn't need a separate treatment. diff --git a/drivers/staging/erofs/namei.c b/drivers/staging/erofs/namei.c @@ -223,18 +223,13 @@ static struct dentry *erofs_lookup(struct inode *dir, if (err == -ENOENT) { /* negative dentry */ inode = NULL; - goto negative_out; - } else if (unlikely(err)) - return ERR_PTR(err); - - debugln("%s, %s (nid %llu) found, d_type %u", __func__, - dentry->d_name.name, nid, d_type); - - inode = erofs_iget(dir->i_sb, nid, d_type == EROFS_FT_DIR); - if (IS_ERR(inode)) - return ERR_CAST(inode); - -negative_out: + } else if (unlikely(err)) { + inode = ERR_PTR(err); + } else { + debugln("%s, %s (nid %llu) found, d_type %u", __func__, + dentry->d_name.name, nid, d_type); + inode = erofs_iget(dir->i_sb, nid, d_type == EROFS_FT_DIR); + } return d_splice_alias(inode, dentry); } diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c @@ -5764,16 +5764,10 @@ static int btrfs_dentry_delete(const struct dentry *dentry) static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) { - struct inode *inode; - - inode = btrfs_lookup_dentry(dir, dentry); - if (IS_ERR(inode)) { - if (PTR_ERR(inode) == -ENOENT) - inode = NULL; - else - return ERR_CAST(inode); - } + struct inode *inode = btrfs_lookup_dentry(dir, dentry); + if (inode == ERR_PTR(-ENOENT)) + inode = NULL; return d_splice_alias(inode, dentry); }