helpers for acl caching + switch to those

helpers: get_cached_acl(inode, type), set_cached_acl(inode, type, acl),
forget_cached_acl(inode, type).

ubifs/xattr.c needed includes reordered, the rest is a plain switchover.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

10 files changed, 155 insertions, 333 deletions

diff --git a/fs/btrfs/acl.c b/fs/btrfs/acl.c
index 6db8a42a3e5e..f128427b995b 100644
--- a/fs/btrfs/acl.c
+++ b/fs/btrfs/acl.c
@@ -29,51 +29,28 @@
 
 #ifdef CONFIG_FS_POSIX_ACL
 
-static void btrfs_update_cached_acl(struct inode *inode,
-                                    struct posix_acl **p_acl,
-                                    struct posix_acl *acl)
-{
-        spin_lock(&inode->i_lock);
-        if (*p_acl && *p_acl != ACL_NOT_CACHED)
-                posix_acl_release(*p_acl);
-        *p_acl = posix_acl_dup(acl);
-        spin_unlock(&inode->i_lock);
-}
-
 static struct posix_acl *btrfs_get_acl(struct inode *inode, int type)
 {
         int size;
         const char *name;
         char *value = NULL;
-        struct posix_acl *acl = NULL, **p_acl;
+        struct posix_acl *acl;
+
+        acl = get_cached_acl(inode, type);
+        if (acl != ACL_NOT_CACHED)
+                return acl;
 
         switch (type) {
         case ACL_TYPE_ACCESS:
                 name = POSIX_ACL_XATTR_ACCESS;
-                p_acl = &inode->i_acl;
                 break;
         case ACL_TYPE_DEFAULT:
                 name = POSIX_ACL_XATTR_DEFAULT;
-                p_acl = &inode->i_default_acl;
                 break;
         default:
-                return ERR_PTR(-EINVAL);
+                BUG();
         }
 
-        /* Handle the cached NULL acl case without locking */
-        acl = ACCESS_ONCE(*p_acl);
-        if (!acl)
-                return acl;
-
-        spin_lock(&inode->i_lock);
-        acl = *p_acl;
-        if (acl != ACL_NOT_CACHED)
-                acl = posix_acl_dup(acl);
-        spin_unlock(&inode->i_lock);
-
-        if (acl != ACL_NOT_CACHED)
-                return acl;
-
         size = __btrfs_getxattr(inode, name, "", 0);
         if (size > 0) {
                 value = kzalloc(size, GFP_NOFS);
@@ -82,13 +59,13 @@ static struct posix_acl *btrfs_get_acl(struct inode *inode, int type)
                 size = __btrfs_getxattr(inode, name, value, size);
                 if (size > 0) {
                         acl = posix_acl_from_xattr(value, size);
-                        btrfs_update_cached_acl(inode, p_acl, acl);
+                        set_cached_acl(inode, type, acl);
                 }
                 kfree(value);
         } else if (size == -ENOENT || size == -ENODATA || size == 0) {
                 /* FIXME, who returns -ENOENT?  I think nobody */
                 acl = NULL;
-                btrfs_update_cached_acl(inode, p_acl, acl);
+                set_cached_acl(inode, type, acl);
         } else {
                 acl = ERR_PTR(-EIO);
         }
@@ -121,7 +98,6 @@ static int btrfs_set_acl(struct inode *inode, struct posix_acl *acl, int type)
 {
         int ret, size = 0;
         const char *name;
-        struct posix_acl **p_acl;
         char *value = NULL;
         mode_t mode;
 
@@ -141,13 +117,11 @@ static int btrfs_set_acl(struct inode *inode, struct posix_acl *acl, int type)
                 ret = 0;
                 inode->i_mode = mode;
                 name = POSIX_ACL_XATTR_ACCESS;
-                p_acl = &inode->i_acl;
                 break;
         case ACL_TYPE_DEFAULT:
                 if (!S_ISDIR(inode->i_mode))
                         return acl ? -EINVAL : 0;
                 name = POSIX_ACL_XATTR_DEFAULT;
-                p_acl = &inode->i_default_acl;
                 break;
         default:
                 return -EINVAL;
@@ -172,7 +146,7 @@ out:
         kfree(value);
 
         if (!ret)
-                btrfs_update_cached_acl(inode, p_acl, acl);
+                set_cached_acl(inode, type, acl);
 
         return ret;
 }
diff --git a/fs/ext2/acl.c b/fs/ext2/acl.c
index d2ffddc12117..d636e1297cad 100644
--- a/fs/ext2/acl.c
+++ b/fs/ext2/acl.c
@@ -125,30 +125,6 @@ fail:
         return ERR_PTR(-EINVAL);
 }
 
-static inline struct posix_acl *
-ext2_iget_acl(struct inode *inode, struct posix_acl **i_acl)
-{
-        struct posix_acl *acl = ACL_NOT_CACHED;
-
-        spin_lock(&inode->i_lock);
-        if (*i_acl != ACL_NOT_CACHED)
-                acl = posix_acl_dup(*i_acl);
-        spin_unlock(&inode->i_lock);
-
-        return acl;
-}
-
-static inline void
-ext2_iset_acl(struct inode *inode, struct posix_acl **i_acl,
-                   struct posix_acl *acl)
-{
-        spin_lock(&inode->i_lock);
-        if (*i_acl != ACL_NOT_CACHED)
-                posix_acl_release(*i_acl);
-        *i_acl = posix_acl_dup(acl);
-        spin_unlock(&inode->i_lock);
-}
-
 /*
  * inode->i_mutex: don't care
  */
@@ -163,23 +139,19 @@ ext2_get_acl(struct inode *inode, int type)
         if (!test_opt(inode->i_sb, POSIX_ACL))
                 return NULL;
 
-        switch(type) {
-                case ACL_TYPE_ACCESS:
-                        acl = ext2_iget_acl(inode, &inode->i_acl);
-                        if (acl != ACL_NOT_CACHED)
-                                return acl;
-                        name_index = EXT2_XATTR_INDEX_POSIX_ACL_ACCESS;
-                        break;
-
-                case ACL_TYPE_DEFAULT:
-                        acl = ext2_iget_acl(inode, &inode->i_default_acl);
-                        if (acl != ACL_NOT_CACHED)
-                                return acl;
-                        name_index = EXT2_XATTR_INDEX_POSIX_ACL_DEFAULT;
-                        break;
-
+        acl = get_cached_acl(inode, type);
+        if (acl != ACL_NOT_CACHED)
+                return acl;
+
+        switch (type) {
+        case ACL_TYPE_ACCESS:
+                name_index = EXT2_XATTR_INDEX_POSIX_ACL_ACCESS;
+                break;
+        case ACL_TYPE_DEFAULT:
+                name_index = EXT2_XATTR_INDEX_POSIX_ACL_DEFAULT;
+                break;
+        default:
+                BUG();