8 files changed, 89 insertions, 94 deletions

diff --git a/fs/block_dev.c b/fs/block_dev.c
index 470c10ceb0fb..10d8a0aa871a 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -931,8 +931,16 @@ static int do_open(struct block_device *bdev, struct file *file, int for_part)
         struct gendisk *disk;
         int ret;
         int part;
+        int perm = 0;
 
-        ret = devcgroup_inode_permission(bdev->bd_inode, file->f_mode);
+        if (file->f_mode & FMODE_READ)
+                perm |= MAY_READ;
+        if (file->f_mode & FMODE_WRITE)
+                perm |= MAY_WRITE;
+        /*
+         * hooks: /n/, see "layering violations".
+         */
+        ret = devcgroup_inode_permission(bdev->bd_inode, perm);
         if (ret != 0)
                 return ret;
 
diff --git a/fs/dcache.c b/fs/dcache.c
index 3ee588d5f585..6068c25b393c 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -17,6 +17,7 @@
 #include <linux/syscalls.h>
 #include <linux/string.h>
 #include <linux/mm.h>
+#include <linux/fdtable.h>
 #include <linux/fs.h>
 #include <linux/fsnotify.h>
 #include <linux/slab.h>
@@ -106,9 +107,10 @@ static void dentry_lru_remove(struct dentry *dentry)
 /*
  * Release the dentry's inode, using the filesystem
  * d_iput() operation if defined.
- * Called with dcache_lock and per dentry lock held, drops both.
  */
 static void dentry_iput(struct dentry * dentry)
+        __releases(dentry->d_lock)
+        __releases(dcache_lock)
 {
         struct inode *inode = dentry->d_inode;
         if (inode) {
@@ -132,12 +134,13 @@ static void dentry_iput(struct dentry * dentry)
  * d_kill - kill dentry and return parent
  * @dentry: dentry to kill
  *
- * Called with dcache_lock and d_lock, releases both.  The dentry must
- * already be unhashed and removed from the LRU.
+ * The dentry must already be unhashed and removed from the LRU.
  *
  * If this is the root of the dentry tree, return NULL.
  */
 static struct dentry *d_kill(struct dentry *dentry)
+        __releases(dentry->d_lock)
+        __releases(dcache_lock)
 {
         struct dentry *parent;
 
@@ -383,11 +386,11 @@ restart:
  * Try to prune ancestors as well.  This is necessary to prevent
  * quadratic behavior of shrink_dcache_parent(), but is also expected
  * to be beneficial in reducing dentry cache fragmentation.
- *
- * Called with dcache_lock, drops it and then regains.
- * Called with dentry->d_lock held, drops it.
  */
 static void prune_one_dentry(struct dentry * dentry)
+        __releases(dentry->d_lock)
+        __releases(dcache_lock)
+        __acquires(dcache_lock)
 {
         __d_drop(dentry);
         dentry = d_kill(dentry);
@@ -1604,10 +1607,9 @@ static int d_isparent(struct dentry *p1, struct dentry *p2)
  *
  * Note: If ever the locking in lock_rename() changes, then please
  * remember to update this too...
- *
- * On return, dcache_lock will have been unlocked.
  */
 static struct dentry *__d_unalias(struct dentry *dentry, struct dentry *alias)
+        __releases(dcache_lock)
 {
         struct mutex *m1 = NULL, *m2 = NULL;
         struct dentry *ret;
@@ -1743,11 +1745,9 @@ out_nolock:
 shouldnt_be_hashed:
         spin_unlock(&dcache_lock);
         BUG();
-        goto shouldnt_be_hashed;
 }
 
-static int prepend(char **buffer, int *buflen, const char *str,
-                          int namelen)
+static int prepend(char **buffer, int *buflen, const char *str, int namelen)
 {
         *buflen -= namelen;
         if (*buflen < 0)
@@ -1757,8 +1757,13 @@ static int prepend(char **buffer, int *buflen, const char *str,
         return 0;
 }
 
+static int prepend_name(char **buffer, int *buflen, struct qstr *name)
+{
+        return prepend(buffer, buflen, name->name, name->len);
+}
+
 /**
- * d_path - return the path of a dentry
+ * __d_path - return the path of a dentry
  * @path: the dentry/vfsmount to report
  * @root: root vfsmnt/dentry (may be modified by this function)
  * @buffer: buffer to return value in
@@ -1779,9 +1784,10 @@ char *__d_path(const struct path *path, struct path *root,
 {
         struct dentry *dentry = path->dentry;
         struct vfsmount *vfsmnt = path->mnt;
-        char * end = buffer+buflen;
-        char * retval;
+        char *end = buffer + buflen;
+        char *retval;
 
+        spin_lock(&vfsmount_lock);
         prepend(&end, &buflen, "\0", 1);
         if (!IS_ROOT(dentry) && d_unhashed(dentry) &&
                 (prepend(&end, &buflen, " (deleted)", 10) != 0))
@@ -1800,38 +1806,37 @@ char *__d_path(const struct path *path, struct path *root,
                         break;
                 if (dentry == vfsmnt->mnt_root || IS_ROOT(dentry)) {
                         /* Global root? */
-                        spin_lock(&vfsmount_lock);
                         if (vfsmnt->mnt_parent == vfsmnt) {
-                                spin_unlock(&vfsmount_lock);
                                 goto global_root;
                         }
                         dentry = vfsmnt->mnt_mountpoint;
                         vfsmnt = vfsmnt->mnt_parent;
-                        spin_unlock(&vfsmount_lock);
                         continue;
                 }
                 parent = dentry->d_parent;
                 prefetch(parent);
-                if ((prepend(&end, &buflen, dentry->d_name.name,
-                                dentry->d_name.len) != 0) ||
+                if ((prepend_name(&end, &buflen, &dentry->d_name) != 0) ||
                     (prepend(&end, &buflen, "/", 1) != 0))
                         goto Elong;
                 retval = end;
                 dentry = parent;
         }
 
+out:
+        spin_unlock(&vfsmount_lock);
         return retval;
 
 global_root:
         retval += 1;    /* hit the slash */
-        if (prepend(&retval, &buflen, dentry->d_name.name,
-                    dentry->d_name.len) != 0)
+        if (prepend_name(&retval, &buflen, &dentry->d_name) != 0)
                 goto Elong;
         root->mnt = vfsmnt;