[RFC][PATCH v3 22/55] merging pick_link() with get_link(), part 5

Al Viro
2020-03-01T21:54:54Z

move get_link() call into step_into().

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
fs/namei.c | 43 ++++++++++++++++++-------------------------
1 file changed, 18 insertions(+), 25 deletions(-)

diff --git a/fs/namei.c b/fs/namei.c
index 21bd4cebd71b..3388958bb32f 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -1841,14 +1841,14 @@ enum {WALK_FOLLOW = 1, WALK_MORE = 2, WALK_NOFOLLOW = 4};
* so we keep a cache of "no, this doesn't need follow_link"
* for the common case.
*/
-static int step_into(struct nameidata *nd, int flags,
+static const char *step_into(struct nameidata *nd, int flags,
struct dentry *dentry, struct inode *inode, unsigned seq)
{
struct path path;
int err = handle_mounts(nd, dentry, &path, &inode, &seq);

if (err < 0)
- return err;
+ return ERR_PTR(err);
if (!(flags & WALK_MORE) && nd->depth)
put_link(nd);
if (likely(!d_is_symlink(path.dentry)) ||
@@ -1858,14 +1858,17 @@ static int step_into(struct nameidata *nd, int flags,
path_to_nameidata(&path, nd);
nd->inode = inode;
nd->seq = seq;
- return 0;
+ return NULL;
}
/* make sure that d_is_symlink above matches inode */
if (nd->flags & LOOKUP_RCU) {
if (read_seqcount_retry(&path.dentry->d_seq, seq))
- return -ECHILD;
+ return ERR_PTR(-ECHILD);
}
- return pick_link(nd, &path, inode, seq);
+ err = pick_link(nd, &path, inode, seq);
+ if (err > 0)
+ return get_link(nd);
+ return ERR_PTR(err);
}

static const char *walk_component(struct nameidata *nd, int flags)
@@ -1893,12 +1896,7 @@ static const char *walk_component(struct nameidata *nd, int flags)
if (IS_ERR(dentry))
return ERR_CAST(dentry);
}
- err = step_into(nd, flags, dentry, inode, seq);
- if (!err)
- return NULL;
- if (err > 0)
- return get_link(nd);
- return ERR_PTR(err);
+ return step_into(nd, flags, dentry, inode, seq);
}

/*
@@ -2352,8 +2350,8 @@ static int handle_lookup_down(struct nameidata *nd)
{
if (!(nd->flags & LOOKUP_RCU))
dget(nd->path.dentry);
- return step_into(nd, WALK_NOFOLLOW,
- nd->path.dentry, nd->inode, nd->seq);
+ return PTR_ERR(step_into(nd, WALK_NOFOLLOW,
+ nd->path.dentry, nd->inode, nd->seq));
}

/* Returns 0 and nd will be valid on success; Retuns error, otherwise. */
@@ -3195,6 +3193,7 @@ static const char *do_last(struct nameidata *nd,
unsigned seq;
struct inode *inode;
struct dentry *dentry;
+ const char *link;
int error;

nd->flags &= ~LOOKUP_PARENT;
@@ -3292,18 +3291,12 @@ static const char *do_last(struct nameidata *nd,
}

finish_lookup:
- error = step_into(nd, 0, dentry, inode, seq);
- if (unlikely(error)) {
- const char *s;
- if (error < 0)
- return ERR_PTR(error);
- s = get_link(nd);
- if (s) {
- nd->flags |= LOOKUP_PARENT;
- nd->flags &= ~(LOOKUP_OPEN|LOOKUP_CREATE|LOOKUP_EXCL);
- nd->stack[0].name = NULL;
- return s;
- }
+ link = step_into(nd, 0, dentry, inode, seq);
+ if (unlikely(link)) {
+ nd->flags |= LOOKUP_PARENT;
+ nd->flags &= ~(LOOKUP_OPEN|LOOKUP_CREATE|LOOKUP_EXCL);
+ nd->stack[0].name = NULL;
+ return link;
}

if (unlikely((open_flag & (O_EXCL | O_CREAT)) == (O_EXCL | O_CREAT))) {
--
2.11.0