Commit 287548e4 authored by Al Viro's avatar Al Viro

split __follow_mount_rcu() into normal and .. cases

Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent dc7acbb2
......@@ -919,12 +919,11 @@ static inline bool managed_dentry_might_block(struct dentry *dentry)
}
/*
* Skip to top of mountpoint pile in rcuwalk mode. We abort the rcu-walk if we
* meet a managed dentry and we're not walking to "..". True is returned to
* continue, false to abort.
* Try to skip to top of mountpoint pile in rcuwalk mode. Fail if
* we meet a managed dentry that would need blocking.
*/
static bool __follow_mount_rcu(struct nameidata *nd, struct path *path,
struct inode **inode, bool reverse_transit)
struct inode **inode)
{
for (;;) {
struct vfsmount *mounted;
......@@ -933,8 +932,7 @@ static bool __follow_mount_rcu(struct nameidata *nd, struct path *path,
* that wants to block transit.
*/
*inode = path->dentry->d_inode;
if (!reverse_transit &&
unlikely(managed_dentry_might_block(path->dentry)))
if (unlikely(managed_dentry_might_block(path->dentry)))
return false;
if (!d_mountpoint(path->dentry))
......@@ -949,10 +947,29 @@ static bool __follow_mount_rcu(struct nameidata *nd, struct path *path,
}
if (unlikely(path->dentry->d_flags & DCACHE_NEED_AUTOMOUNT))
return reverse_transit;
return false;
return true;
}
static void follow_mount_rcu(struct nameidata *nd, struct path *path,
struct inode **inode)
{
for (;;) {
struct vfsmount *mounted;
*inode = path->dentry->d_inode;
if (!d_mountpoint(path->dentry))
break;
mounted = __lookup_mnt(path->mnt, path->dentry, 1);
if (!mounted)
break;
path->mnt = mounted;
path->dentry = mounted->mnt_root;
nd->seq = read_seqcount_begin(&path->dentry->d_seq);
}
}
static int follow_dotdot_rcu(struct nameidata *nd)
{
struct inode *inode = nd->inode;
......@@ -982,7 +999,7 @@ static int follow_dotdot_rcu(struct nameidata *nd)
nd->seq = read_seqcount_begin(&nd->path.dentry->d_seq);
inode = nd->path.dentry->d_inode;
}
__follow_mount_rcu(nd, &nd->path, &inode, true);
follow_mount_rcu(nd, &nd->path, &inode);
nd->inode = inode;
return 0;
......@@ -1157,7 +1174,7 @@ static int do_lookup(struct nameidata *nd, struct qstr *name,
}
path->mnt = mnt;
path->dentry = dentry;
if (likely(__follow_mount_rcu(nd, path, inode, false)))
if (likely(__follow_mount_rcu(nd, path, inode)))
return 0;
unlazy:
if (unlazy_walk(nd, dentry))
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment