autofs4 - remove autofs4_lock

The autofs4_lock introduced by the rcu-walk changes has unnecessarily
broad scope. The locking is better handled by the per-autofs super
block lookup_lock.

Signed-off-by: Ian Kent <raven@themaw.net>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 7 insertions, 18 deletions

diff --git a/fs/autofs4/root.c b/fs/autofs4/root.c
index ebbfa0ce6d7b..96804a17bbd0 100644
--- a/fs/autofs4/root.c
+++ b/fs/autofs4/root.c
@@ -23,8 +23,6 @@
 
 #include "autofs_i.h"
 
-DEFINE_SPINLOCK(autofs4_lock);
-
 static int autofs4_dir_symlink(struct inode *,struct dentry *,const char *);
 static int autofs4_dir_unlink(struct inode *,struct dentry *);
 static int autofs4_dir_rmdir(struct inode *,struct dentry *);
@@ -125,15 +123,15 @@ static int autofs4_dir_open(struct inode *inode, struct file *file)
          * autofs file system so just let the libfs routines handle
          * it.
          */
-        spin_lock(&autofs4_lock);
+        spin_lock(&sbi->lookup_lock);
         spin_lock(&dentry->d_lock);
         if (!d_mountpoint(dentry) && list_empty(&dentry->d_subdirs)) {
                 spin_unlock(&dentry->d_lock);
-                spin_unlock(&autofs4_lock);
+                spin_unlock(&sbi->lookup_lock);
                 return -ENOENT;
         }
         spin_unlock(&dentry->d_lock);
-        spin_unlock(&autofs4_lock);
+        spin_unlock(&sbi->lookup_lock);
 
 out:
         return dcache_dir_open(inode, file);
@@ -171,7 +169,6 @@ static struct dentry *autofs4_lookup_active(struct dentry *dentry)
         const unsigned char *str = name->name;
         struct list_head *p, *head;
 
-        spin_lock(&autofs4_lock);
         spin_lock(&sbi->lookup_lock);
         head = &sbi->active_list;
         list_for_each(p, head) {
@@ -204,14 +201,12 @@ static struct dentry *autofs4_lookup_active(struct dentry *dentry)
                         dget_dlock(active);
                         spin_unlock(&active->d_lock);
                         spin_unlock(&sbi->lookup_lock);
-                        spin_unlock(&autofs4_lock);
                         return active;
                 }
 next:
                 spin_unlock(&active->d_lock);
         }
         spin_unlock(&sbi->lookup_lock);
-        spin_unlock(&autofs4_lock);
 
         return NULL;
 }
@@ -226,7 +221,6 @@ static struct dentry *autofs4_lookup_expiring(struct dentry *dentry)
         const unsigned char *str = name->name;
         struct list_head *p, *head;
 
-        spin_lock(&autofs4_lock);
         spin_lock(&sbi->lookup_lock);
         head = &sbi->expiring_list;
         list_for_each(p, head) {
@@ -259,14 +253,12 @@ static struct dentry *autofs4_lookup_expiring(struct dentry *dentry)
                         dget_dlock(expiring);
                         spin_unlock(&expiring->d_lock);
                         spin_unlock(&sbi->lookup_lock);
-                        spin_unlock(&autofs4_lock);
                         return expiring;
                 }
 next:
                 spin_unlock(&expiring->d_lock);
         }
         spin_unlock(&sbi->lookup_lock);
-        spin_unlock(&autofs4_lock);
 
         return NULL;
 }
@@ -603,12 +595,12 @@ static int autofs4_dir_unlink(struct inode *dir, struct dentry *dentry)
 
         dir->i_mtime = CURRENT_TIME;
 
-        spin_lock(&autofs4_lock);
-        autofs4_add_expiring(dentry);
+        spin_lock(&sbi->lookup_lock);
+        __autofs4_add_expiring(dentry);
         spin_lock(&dentry->d_lock);
         __d_drop(dentry);
         spin_unlock(&dentry->d_lock);
-        spin_unlock(&autofs4_lock);
+        spin_unlock(&sbi->lookup_lock);
 
         return 0;
 }
@@ -677,20 +669,17 @@ static int autofs4_dir_rmdir(struct inode *dir, struct dentry *dentry)
         if (!autofs4_oz_mode(sbi))
                 return -EACCES;
 
-        spin_lock(&autofs4_lock);
         spin_lock(&sbi->lookup_lock);
         spin_lock(&dentry->d_lock);
         if (!list_empty(&dentry->d_subdirs)) {
                 spin_unlock(&dentry->d_lock);
                 spin_unlock(&sbi->lookup_lock);
-                spin_unlock(&autofs4_lock);
                 return -ENOTEMPTY;
         }
         __autofs4_add_expiring(dentry);
-        spin_unlock(&sbi->lookup_lock);
         __d_drop(dentry);
         spin_unlock(&dentry->d_lock);
-        spin_unlock(&autofs4_lock);
+        spin_unlock(&sbi->lookup_lock);
 
         if (sbi->version < 5)
                 autofs_clear_leaf_automount_flags(dentry);