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>

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 @@ static int btrfs_set_acl(struct inode *inode, struct posix_acl *acl, int type)
 	kfree(value);
 
 	if (!ret)
-		btrfs_update_cached_acl(inode, p_acl, acl);
+		set_cached_acl(inode, type, acl);
 
 	return ret;
 }

fs/ext2/acl.c

@@ -125,30 +125,6 @@ ext2_acl_to_disk(const struct posix_acl *acl, size_t *size)
 	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;
-
-		default:
-			return ERR_PTR(-EINVAL);
+	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();
 	}
 	retval = ext2_xattr_get(inode, name_index, "", NULL, 0);
 	if (retval > 0) {
@@ -196,17 +168,9 @@ ext2_get_acl(struct inode *inode, int type)
 		acl = ERR_PTR(retval);
 	kfree(value);
 
-	if (!IS_ERR(acl)) {
-		switch(type) {
-			case ACL_TYPE_ACCESS:
-				ext2_iset_acl(inode, &inode->i_acl, acl);
-				break;
+	if (!IS_ERR(acl))
+		set_cached_acl(inode, type, acl);
 
-			case ACL_TYPE_DEFAULT:
-				ext2_iset_acl(inode, &inode->i_default_acl, acl);
-				break;
-		}
-	}
 	return acl;
 }
 
@@ -261,17 +225,8 @@ ext2_set_acl(struct inode *inode, int type, struct posix_acl *acl)
 	error = ext2_xattr_set(inode, name_index, "", value, size, 0);
 
 	kfree(value);
-	if (!error) {
-		switch(type) {
-			case ACL_TYPE_ACCESS:
-				ext2_iset_acl(inode, &inode->i_acl, acl);
-				break;
-
-			case ACL_TYPE_DEFAULT:
-				ext2_iset_acl(inode, &inode->i_default_acl, acl);
-				break;
-		}
-	}
+	if (!error)
+		set_cached_acl(inode, type, acl);
 	return error;
 }
 

fs/ext3/acl.c

@@ -126,33 +126,6 @@ ext3_acl_to_disk(const struct posix_acl *acl, size_t *size)
 	return ERR_PTR(-EINVAL);
 }
 
-static inline struct posix_acl *
-ext3_iget_acl(struct inode *inode, struct posix_acl **i_acl)
-{
-	struct posix_acl *acl = ACCESS_ONCE(*i_acl);
-
-	if (acl) {
-		spin_lock(&inode->i_lock);
-		acl = *i_acl;
-		if (acl != ACL_NOT_CACHED)
-			acl = posix_acl_dup(acl);
-		spin_unlock(&inode->i_lock);
-	}
-
-	return acl;
-}
-
-static inline void
-ext3_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 operation get_posix_acl().
  *
@@ -169,24 +142,21 @@ ext3_get_acl(struct inode *inode, int type)
 	if (!test_opt(inode->i_sb, POSIX_ACL))
 		return NULL;
 
-	switch(type) {
-		case ACL_TYPE_ACCESS:
-			acl = ext3_iget_acl(inode, &inode->i_acl);
-			if (acl != ACL_NOT_CACHED)
-				return acl;
-			name_index = EXT3_XATTR_INDEX_POSIX_ACL_ACCESS;
-			break;
-
-		case ACL_TYPE_DEFAULT:
-			acl = ext3_iget_acl(inode, &inode->i_default_acl);
-			if (acl != ACL_NOT_CACHED)
-				return acl;
-			name_index = EXT3_XATTR_INDEX_POSIX_ACL_DEFAULT;
-			break;
-
-		default:
-			return ERR_PTR(-EINVAL);
+	acl = get_cached_acl(inode, type);
+	if (acl != ACL_NOT_CACHED)
+		return acl;
+
+	switch (type) {
+	case ACL_TYPE_ACCESS:
+		name_index = EXT3_XATTR_INDEX_POSIX_ACL_ACCESS;
+		break;
+	case ACL_TYPE_DEFAULT:
+		name_index = EXT3_XATTR_INDEX_POSIX_ACL_DEFAULT;
+		break;
+	default:
+		BUG();
 	}
+
 	retval = ext3_xattr_get(inode, name_index, "", NULL, 0);
 	if (retval > 0) {
 		value = kmalloc(retval, GFP_NOFS);
@@ -202,17 +172,9 @@ ext3_get_acl(struct inode *inode, int type)
 		acl = ERR_PTR(retval);
 	kfree(value);
 
-	if (!IS_ERR(acl)) {
-		switch(type) {
-			case ACL_TYPE_ACCESS:
-				ext3_iset_acl(inode, &inode->i_acl, acl);
-				break;
+	if (!IS_ERR(acl))
+		set_cached_acl(inode, type, acl);
 
-			case ACL_TYPE_DEFAULT:
-				ext3_iset_acl(inode, &inode->i_default_acl, acl);
-				break;
-		}
-	}
 	return acl;
 }
 
@@ -269,17 +231,10 @@ ext3_set_acl(handle_t *handle, struct inode *inode, int type,
 				      value, size, 0);
 
 	kfree(value);
-	if (!error) {
-		switch(type) {
-			case ACL_TYPE_ACCESS:
-				ext3_iset_acl(inode, &inode->i_acl, acl);
-				break;
 
-			case ACL_TYPE_DEFAULT:
-				ext3_iset_acl(inode, &inode->i_default_acl, acl);
-				break;
-		}
-	}
+	if (!error)
+		set_cached_acl(inode, type, acl);
+
 	return error;
 }
 

fs/ext4/acl.c

@@ -126,33 +126,6 @@ ext4_acl_to_disk(const struct posix_acl *acl, size_t *size)
 	return ERR_PTR(-EINVAL);
 }
 
-static inline struct posix_acl *
-ext4_iget_acl(struct inode *inode, struct posix_acl **i_acl)
-{
-	struct posix_acl *acl = ACCESS_ONCE(*i_acl);
-
-	if (acl) {
-		spin_lock(&inode->i_lock);
-		acl = *i_acl;
-		if (acl != ACL_NOT_CACHED)
-			acl = posix_acl_dup(acl);
-		spin_unlock(&inode->i_lock);
-	}
-
-	return acl;
-}
-
-static inline void
-ext4_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 operation get_posix_acl().
  *
@@ -169,23 +142,19 @@ ext4_get_acl(struct inode *inode, int type)
 	if (!test_opt(inode->i_sb, POSIX_ACL))
 		return NULL;
 
+	acl = get_cached_acl(inode, type);
+	if (acl != ACL_NOT_CACHED)
+		return acl;
+
 	switch (type) {
 	case ACL_TYPE_ACCESS:
-		acl = ext4_iget_acl(inode, &inode->i_acl);
-		if (acl != ACL_NOT_CACHED)
-			return acl;
 		name_index = EXT4_XATTR_INDEX_POSIX_ACL_ACCESS;
 		break;
-
 	case ACL_TYPE_DEFAULT:
-		acl = ext4_iget_acl(inode, &inode->i_default_acl);
-		if (acl != ACL_NOT_CACHED)
-			return acl;
 		name_index = EXT4_XATTR_INDEX_POSIX_ACL_DEFAULT;
 		break;
-
 	default:
-		return ERR_PTR(-EINVAL);
+		BUG();
 	}
 	retval = ext4_xattr_get(inode, name_index, "", NULL, 0);
 	if (retval > 0) {
@@ -202,17 +171,9 @@ ext4_get_acl(struct inode *inode, int type)
 		acl = ERR_PTR(retval);
 	kfree(value);
 
-	if (!IS_ERR(acl)) {
-		switch (type) {
-		case ACL_TYPE_ACCESS:
-			ext4_iset_acl(inode, &inode->i_acl, acl);
-			break;
+	if (!IS_ERR(acl))
+		set_cached_acl(inode, type, acl);
 
-		case ACL_TYPE_DEFAULT:
-			ext4_iset_acl(inode, &inode->i_default_acl, acl);
-			break;
-		}
-	}
 	return acl;
 }
 
@@ -269,17 +230,9 @@ ext4_set_acl(handle_t *handle, struct inode *inode, int type,
 				      value, size, 0);
 
 	kfree(value);
-	if (!error) {
-		switch (type) {
-		case ACL_TYPE_ACCESS:
-			ext4_iset_acl(inode, &inode->i_acl, acl);
-			break;
+	if (!error)
+		set_cached_acl(inode, type, acl);
 
-		case ACL_TYPE_DEFAULT:
-			ext4_iset_acl(inode, &inode->i_default_acl, acl);
-			break;
-		}
-	}
 	return error;
 }
 

fs/jffs2/acl.c

@@ -156,47 +156,25 @@ static void *jffs2_acl_to_medium(const struct posix_acl *acl, size_t *size)
 	return ERR_PTR(-EINVAL);
 }
 
-static struct posix_acl *jffs2_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 void jffs2_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);
-}
-
 static struct posix_acl *jffs2_get_acl(struct inode *inode, int type)
 {
 	struct posix_acl *acl;
 	char *value = NULL;
 	int rc, xprefix;
 
+	acl = get_cached_acl(inode, type);
+	if (acl != ACL_NOT_CACHED)
+		return acl;
+
 	switch (type) {
 	case ACL_TYPE_ACCESS:
-		acl = jffs2_iget_acl(inode, &inode->i_acl);
-		if (acl != ACL_NOT_CACHED)
-			return acl;
 		xprefix = JFFS2_XPREFIX_ACL_ACCESS;
 		break;
 	case ACL_TYPE_DEFAULT:
-		acl = jffs2_iget_acl(inode, &inode->i_default_acl);
-		if (acl != ACL_NOT_CACHED)
-			return acl;
 		xprefix = JFFS2_XPREFIX_ACL_DEFAULT;
 		break;
 	default:
-		return ERR_PTR(-EINVAL);
+		BUG();
 	}
 	rc = do_jffs2_getxattr(inode, xprefix, "", NULL, 0);
 	if (rc > 0) {
@@ -214,16 +192,8 @@ static struct posix_acl *jffs2_get_acl(struct inode *inode, int type)
 	}
 	if (value)
 		kfree(value);
-	if (!IS_ERR(acl)) {
-		switch (type) {
-		case ACL_TYPE_ACCESS:
-			jffs2_iset_acl(inode, &inode->i_acl, acl);
-			break;
-		case ACL_TYPE_DEFAULT:
-			jffs2_iset_acl(inode, &inode->i_default_acl, acl);
-			break;
-		}
-	}
+	if (!IS_ERR(acl))
+		set_cached_acl(inode, type, acl);
 	return acl;
 }
 
@@ -283,16 +253,8 @@ static int jffs2_set_acl(struct inode *inode, int type, struct posix_acl *acl)
 		return -EINVAL;
 	}
 	rc = __jffs2_set_acl(inode, xprefix, acl);
-	if (!rc) {
-		switch(type) {
-		case ACL_TYPE_ACCESS:
-			jffs2_iset_acl(inode, &inode->i_acl, acl);
-			break;
-		case ACL_TYPE_DEFAULT:
-			jffs2_iset_acl(inode, &inode->i_default_acl, acl);
-			break;
-		}
-	}
+	if (!rc)
+		set_cached_acl(inode, type, acl);
 	return rc;
 }
 
@@ -336,7 +298,7 @@ int jffs2_init_acl_pre(struct inode *dir_i, struct inode *inode, int *i_mode)
 		*i_mode &= ~current_umask();
 	} else {
 		if (S_ISDIR(*i_mode))
-			jffs2_iset_acl(inode, &inode->i_default_acl, acl);
+			set_cached_acl(inode, ACL_TYPE_DEFAULT, acl);
 
 		clone = posix_acl_clone(acl, GFP_KERNEL);
 		if (!clone)
@@ -347,7 +309,7 @@ int jffs2_init_acl_pre(struct inode *dir_i, struct inode *inode, int *i_mode)
 			return rc;
 		}
 		if (rc > 0)
-			jffs2_iset_acl(inode, &inode->i_acl, clone);
+			set_cached_acl(inode, ACL_TYPE_ACCESS, clone);
 
 		posix_acl_release(clone);
 	}

fs/jfs/acl.c

@@ -31,26 +31,24 @@ static struct posix_acl *jfs_get_acl(struct inode *inode, int type)
 {
 	struct posix_acl *acl;
 	char *ea_name;
-	struct posix_acl **p_acl;
 	int size;
 	char *value = NULL;
 
+	acl = get_cached_acl(inode, type);
+	if (acl != ACL_NOT_CACHED)
+		return acl;
+
 	switch(type) {
 		case ACL_TYPE_ACCESS:
 			ea_name = POSIX_ACL_XATTR_ACCESS;
-			p_acl = &inode->i_acl;
 			break;
 		case ACL_TYPE_DEFAULT:
 			ea_name = POSIX_ACL_XATTR_DEFAULT;
-			p_acl = &inode->i_default_acl;
 			break;
 		default:
 			return ERR_PTR(-EINVAL);
 	}
 
-	if (*p_acl != ACL_NOT_CACHED)
-		return posix_acl_dup(*p_acl);
-
 	size = __jfs_getxattr(inode, ea_name, NULL, 0);
 
 	if (size > 0) {
@@ -61,17 +59,18 @@ static struct posix_acl *jfs_get_acl(struct inode *inode, int type)
 	}
 
 	if (size < 0) {
-		if (size == -ENODATA) {
-			*p_acl = NULL;
+		if (size == -ENODATA)
 			acl = NULL;
-		} else
+		else
 			acl = ERR_PTR(size);
 	} else {
 		acl = posix_acl_from_xattr(value, size);
-		if (!IS_ERR(acl))
-			*p_acl = posix_acl_dup(acl);
 	}
 	kfree(value);
+	if (!IS_ERR(acl)) {
+		set_cached_acl(inode, type, acl);
+		posix_acl_release(acl);
+	}
 	return acl;
 }
 
@@ -79,7 +78,6 @@ static int jfs_set_acl(tid_t tid, struct inode *inode, int type,
 		       struct posix_acl *acl)
 {
 	char *ea_name;
-	struct posix_acl **p_acl;
 	int rc;
 	int size = 0;
 	char *value = NULL;
@@ -90,11 +88,9 @@ static int jfs_set_acl(tid_t tid, struct inode *inode, int type,
 	switch(type) {
 		case ACL_TYPE_ACCESS:
 			ea_name = POSIX_ACL_XATTR_ACCESS;
-			p_acl = &inode->i_acl;
 			break;
 		case ACL_TYPE_DEFAULT:
 			ea_name = POSIX_ACL_XATTR_DEFAULT;
-			p_acl = &inode->i_default_acl;
 			if (!S_ISDIR(inode->i_mode))
 				return acl ? -EACCES : 0;
 			break;
@@ -114,11 +110,9 @@ static int jfs_set_acl(tid_t tid, struct inode *inode, int type,
 out:
 	kfree(value);
 
-	if (!rc) {
-		if (*p_acl && (*p_acl != ACL_NOT_CACHED))
-			posix_acl_release(*p_acl);
-		*p_acl = posix_acl_dup(acl);
-	}
+	if (!rc)
+		set_cached_acl(inode, type, acl);
+
 	return rc;
 }
 

fs/jfs/xattr.c

@@ -727,10 +727,7 @@ static int can_set_system_xattr(struct inode *inode, const char *name,
 		/*
 		 * We're changing the ACL.  Get rid of the cached one
 		 */
-		acl =inode->i_acl;
-		if (acl != ACL_NOT_CACHED)
-			posix_acl_release(acl);
-		inode->i_acl = ACL_NOT_CACHED;
+		forget_cached_acl(inode, ACL_TYPE_ACCESS);
 
 		return 0;
 	} else if (strcmp(name, POSIX_ACL_XATTR_DEFAULT) == 0) {
@@ -746,10 +743,7 @@ static int can_set_system_xattr(struct inode *inode, const char *name,
 		/*
 		 * We're changing the default ACL.  Get rid of the cached one
 		 */
-		acl = inode->i_default_acl;
-		if (acl && (acl != ACL_NOT_CACHED))
-			posix_acl_release(acl);
-		inode->i_default_acl = ACL_NOT_CACHED;
+		forget_cached_acl(inode, ACL_TYPE_DEFAULT);
 
 		return 0;
 	}

fs/reiserfs/xattr_acl.c

@@ -188,29 +188,6 @@ static void *posix_acl_to_disk(const struct posix_acl *acl, size_t * size)
 	return ERR_PTR(-EINVAL);
 }
 
-static inline void 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);
-}
-
-static inline struct posix_acl *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;
-}
-
 /*
  * Inode operation get_posix_acl().
  *
@@ -220,31 +197,29 @@ static inline struct posix_acl *iget_acl(struct inode *inode,
 struct posix_acl *reiserfs_get_acl(struct inode *inode, int type)
 {
 	char *name, *value;
-	struct posix_acl *acl, **p_acl;
+	struct posix_acl *acl;
 	int size;
 	int retval;
 
+	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();
 	}
 
-	acl = iget_acl(inode, p_acl);
-	if (acl != ACL_NOT_CACHED)
-		return acl;
-
 	size = reiserfs_xattr_get(inode, name, NULL, 0);
 	if (size < 0) {
 		if (size == -ENODATA || size == -ENOSYS) {
-			*p_acl = NULL;
+			set_cached_acl(inode, type, NULL);
 			return NULL;
 		}
 		return ERR_PTR(size);
@@ -259,14 +234,13 @@ struct posix_acl *reiserfs_get_acl(struct inode *inode, int type)
 		/* This shouldn't actually happen as it should have
 		   been caught above.. but just in case */
 		acl = NULL;
-		*p_acl = acl;
 	} else if (retval < 0) {
 		acl = ERR_PTR(retval);
 	} else {
 		acl = posix_acl_from_disk(value, retval);
-		if (!IS_ERR(acl))
-			iset_acl(inode, p_acl, acl);
 	}
+	if (!IS_ERR(acl))
+		set_cached_acl(inode, type, acl);
 
 	kfree(value);
 	return acl;
@@ -284,7 +258,6 @@ reiserfs_set_acl(struct reiserfs_transaction_handle *th, struct inode *inode,
 {
 	char *name;
 	void *value = NULL;
-	struct posix_acl **p_acl;
 	size_t size = 0;
 	int error;
 
@@ -294,7 +267,6 @@ reiserfs_set_acl(struct reiserfs_transaction_handle *th, struct inode *inode,
 	switch (type) {
 	case ACL_TYPE_ACCESS:
 		name = POSIX_ACL_XATTR_ACCESS;
-		p_acl = &inode->i_acl;
 		if (acl) {
 			mode_t mode = inode->i_mode;
 			error = posix_acl_equiv_mode(acl, &mode);
@@ -309,7 +281,6 @@ reiserfs_set_acl(struct reiserfs_transaction_handle *th, struct inode *inode,
 		break;
 	case ACL_TYPE_DEFAULT:
 		name = POSIX_ACL_XATTR_DEFAULT;
-		p_acl = &inode->i_default_acl;
 		if (!S_ISDIR(inode->i_mode))
 			return acl ? -EACCES : 0;
 		break;
@@ -342,7 +313,7 @@ reiserfs_set_acl(struct reiserfs_transaction_handle *th, struct inode *inode,
 	kfree(value);
 
 	if (!error)
-		iset_acl(inode, p_acl, acl);
+		set_cached_acl(inode, type, acl);
 
 	return error;
 }

fs/ubifs/xattr.c

@@ -55,9 +55,9 @@
  * ACL support is not implemented.
  */
 
+#include "ubifs.h"
 #include <linux/xattr.h>
 #include <linux/posix_acl_xattr.h>
-#include "ubifs.h"
 
 /*
  * Limit the number of extended attributes per inode so that the total size

include/linux/posix_acl.h

@@ -83,4 +83,68 @@ extern int posix_acl_chmod_masq(struct posix_acl *, mode_t);
 extern struct posix_acl *get_posix_acl(struct inode *, int);
 extern int set_posix_acl(struct inode *, int, struct posix_acl *);
 
+static inline struct posix_acl *get_cached_acl(struct inode *inode, int type)
+{
+	struct posix_acl **p, *acl;
+	switch (type) {
+	case ACL_TYPE_ACCESS:
+		p = &inode->i_acl;
+		break;
+	case ACL_TYPE_DEFAULT:
+		p = &inode->i_default_acl;
+		break;
+	default:
+		return ERR_PTR(-EINVAL);
+	}
+	acl = ACCESS_ONCE(*p);
+	if (acl) {
+		spin_lock(&inode->i_lock);
+		acl = *p;
+		if (acl != ACL_NOT_CACHED)
+			acl = posix_acl_dup(acl);
+		spin_unlock(&inode->i_lock);
+	}
+	return acl;
+}
+
+static inline void set_cached_acl(struct inode *inode,
+				  int type,
+				  struct posix_acl *acl)
+{
+	struct posix_acl *old = NULL;
+	spin_lock(&inode->i_lock);
+	switch (type) {
+	case ACL_TYPE_ACCESS:
+		old = inode->i_acl;
+		inode->i_acl = posix_acl_dup(acl);
+		break;
+	case ACL_TYPE_DEFAULT:
+		old = inode->i_default_acl;
+		inode->i_default_acl = posix_acl_dup(acl);
+		break;
+	}
+	spin_unlock(&inode->i_lock);
+	if (old != ACL_NOT_CACHED)
+		posix_acl_release(old);
+}
+
+static inline void forget_cached_acl(struct inode *inode, int type)
+{
+	struct posix_acl *old = NULL;
+	spin_lock(&inode->i_lock);
+	switch (type) {
+	case ACL_TYPE_ACCESS:
+		old = inode->i_acl;
+		inode->i_acl = ACL_NOT_CACHED;
+		break;
+	case ACL_TYPE_DEFAULT:
+		old = inode->i_default_acl;
+		inode->i_default_acl = ACL_NOT_CACHED;
+		break;
+	}
+	spin_unlock(&inode->i_lock);
+	if (old != ACL_NOT_CACHED)
+		posix_acl_release(old);
+}
+
 #endif  /* __LINUX_POSIX_ACL_H */