merging pick_link() with get_link(), part 5

move get_link() call into step_into().

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro 2020-01-14 13:34:20 -05:00
parent 92d270165c
commit b0417d2c72
1 changed files with 18 additions and 25 deletions

View File

@ -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 (likely(!d_is_symlink(path.dentry)) ||
!((flags & WALK_FOLLOW) || (nd->flags & LOOKUP_FOLLOW)) ||
(flags & WALK_NOFOLLOW)) {
@ -1856,14 +1856,17 @@ 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 (!(flags & WALK_MORE) && nd->depth)
put_link(nd);
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. */
@ -3193,6 +3191,7 @@ static const char *do_last(struct nameidata *nd,
unsigned seq;
struct inode *inode;
struct dentry *dentry;
const char *res;
int error;
nd->flags &= ~LOOKUP_PARENT;
@ -3294,18 +3293,12 @@ static const char *do_last(struct nameidata *nd,
finish_lookup:
if (nd->depth)
put_link(nd);
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;
}
res = step_into(nd, 0, dentry, inode, seq);
if (unlikely(res)) {
nd->flags |= LOOKUP_PARENT;
nd->flags &= ~(LOOKUP_OPEN|LOOKUP_CREATE|LOOKUP_EXCL);
nd->stack[0].name = NULL;
return res;
}
if (unlikely((open_flag & (O_EXCL | O_CREAT)) == (O_EXCL | O_CREAT))) {