get rid of boilerplate switches in posix_acl.h

the only potentially subtle thing here: get_cached_acl()
is never called with the second argument other than
ACL_TYPE_{ACCESS,DEFAULT}.  IOW, that return ERR_PTR(-EINVAL)
in there might as well be BUG().

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

1 files changed, 20 insertions, 42 deletions

diff --git a/include/linux/posix_acl.h b/include/linux/posix_acl.h
index 951bba82d50d..a9c2fb29be96 100644
--- a/include/linux/posix_acl.h
+++ b/include/linux/posix_acl.h
@@ -84,20 +84,22 @@ extern struct posix_acl *get_posix_acl(struct inode *, int);
 extern int set_posix_acl(struct inode *, int, struct posix_acl *);
 
 #ifdef CONFIG_FS_POSIX_ACL
-static inline struct posix_acl *get_cached_acl(struct inode *inode, int type)
+static inline struct posix_acl **acl_by_type(struct inode *inode, int type)
 {
-        struct posix_acl **p, *acl;
         switch (type) {
         case ACL_TYPE_ACCESS:
-                p = &inode->i_acl;
-                break;
+                return &inode->i_acl;
         case ACL_TYPE_DEFAULT:
-                p = &inode->i_default_acl;
-                break;
+                return &inode->i_default_acl;
         default:
-                return ERR_PTR(-EINVAL);
+                BUG();
         }
-        acl = ACCESS_ONCE(*p);
+}
+
+static inline struct posix_acl *get_cached_acl(struct inode *inode, int type)
+{
+        struct posix_acl **p = acl_by_type(inode, type);
+        struct posix_acl *acl = ACCESS_ONCE(*p);
         if (acl) {
                 spin_lock(&inode->i_lock);
                 acl = *p;
@@ -110,18 +112,8 @@ static inline struct posix_acl *get_cached_acl(struct inode *inode, int type)
 
 static inline int negative_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:
-                BUG();
-        }
-        acl = ACCESS_ONCE(*p);
+        struct posix_acl **p = acl_by_type(inode, type);
+        struct posix_acl *acl = ACCESS_ONCE(*p);
         if (acl)
                 return 0;
         return 1;
@@ -131,18 +123,11 @@ static inline void set_cached_acl(struct inode *inode,
                                   int type,
                                   struct posix_acl *acl)
 {
-        struct posix_acl *old = NULL;
+        struct posix_acl **p = acl_by_type(inode, type);
+        struct posix_acl *old;
         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;
-        }
+        old = *p;
+        *p = posix_dup_acl(acl);
         spin_unlock(&inode->i_lock);
         if (old != ACL_NOT_CACHED)
                 posix_acl_release(old);
@@ -150,18 +135,11 @@ static inline void set_cached_acl(struct inode *inode,
 
 static inline void forget_cached_acl(struct inode *inode, int type)
 {
-        struct posix_acl *old = NULL;
+        struct posix_acl **p = acl_by_type(inode, type);
+        struct posix_acl *old;
         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;
-        }
+        old = *p;
+        *p = ACL_NOT_CACHED;
         spin_unlock(&inode->i_lock);
         if (old != ACL_NOT_CACHED)
                 posix_acl_release(old);