diff options
| -rw-r--r-- | fs/autofs4/root.c | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/fs/autofs4/root.c b/fs/autofs4/root.c index aa4c5ff8a40d..0533d37c73ae 100644 --- a/fs/autofs4/root.c +++ b/fs/autofs4/root.c @@ -242,6 +242,7 @@ static int try_to_fill_dentry(struct dentry *dentry, int flags) { struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb); struct autofs_info *ino = autofs4_dentry_ino(dentry); + struct dentry *new; int status = 0; /* Block on any pending expiry here; invalidate the dentry @@ -318,6 +319,27 @@ static int try_to_fill_dentry(struct dentry *dentry, int flags) spin_lock(&dentry->d_lock); dentry->d_flags &= ~DCACHE_AUTOFS_PENDING; spin_unlock(&dentry->d_lock); + + /* + * The dentry that is passed in from lookup may not be the one + * we end up using, as mkdir can create a new one. If this + * happens, and another process tries the lookup at the same time, + * it will set the PENDING flag on this new dentry, but add itself + * to our waitq. Then, if after the lookup succeeds, the first + * process that requested the mount performs another lookup of the + * same directory, it will show up as still pending! So, we need + * to redo the lookup here and clear pending on that dentry. + */ + if (d_unhashed(dentry)) { + new = d_lookup(dentry->d_parent, &dentry->d_name); + if (new) { + spin_lock(&new->d_lock); + new->d_flags &= ~DCACHE_AUTOFS_PENDING; + spin_unlock(&new->d_lock); + dput(new); + } + } + return status; } |