[PATCH] spufs: dont hold root->isem in spu_forget

spu_forget will do mmput on the DMA address space,
which can lead to lots of other stuff getting triggered.
We better not hold a semaphore here that we might
need in the process.

Noticed by Al Viro.

Signed-off-by: Arnd Bergmann <arndb@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 10 insertions, 10 deletions

diff --git a/arch/powerpc/platforms/cell/spufs/inode.c b/arch/powerpc/platforms/cell/spufs/inode.c
index 2c3ba4eb41cb..45944012b06a 100644
--- a/arch/powerpc/platforms/cell/spufs/inode.c
+++ b/arch/powerpc/platforms/cell/spufs/inode.c
@@ -162,10 +162,10 @@ static int spufs_rmdir(struct inode *root, struct dentry *dir_dentry)
 {
         struct dentry *dentry, *tmp;
         struct spu_context *ctx;
-        int err;
 
         /* remove all entries */
-        err = 0;
+        down(&root->i_sem);
+        down(&dir_dentry->d_inode->i_sem);
         list_for_each_entry_safe(dentry, tmp, &dir_dentry->d_subdirs, d_child) {
                 spin_lock(&dcache_lock);
                 spin_lock(&dentry->d_lock);
@@ -181,16 +181,16 @@ static int spufs_rmdir(struct inode *root, struct dentry *dir_dentry)
                         spin_unlock(&dcache_lock);
                 }
         }
+        shrink_dcache_parent(dir_dentry);
+        up(&dir_dentry->d_inode->i_sem);
+        up(&root->i_sem);
 
         /* We have to give up the mm_struct */
         ctx = SPUFS_I(dir_dentry->d_inode)->i_ctx;
         spu_forget(ctx);
 
-        if (!err) {
-                shrink_dcache_parent(dir_dentry);
-                err = simple_rmdir(root, dir_dentry);
-        }
-        return err;
+        /* XXX Do we need to hold i_sem here ? */
+        return simple_rmdir(root, dir_dentry);
 }
 
 static int spufs_dir_close(struct inode *inode, struct file *file)
@@ -201,10 +201,10 @@ static int spufs_dir_close(struct inode *inode, struct file *file)
 
         dentry = file->f_dentry;
         dir = dentry->d_parent->d_inode;
-        down(&dir->i_sem);
-        ret = spufs_rmdir(dir, file->f_dentry);
+
+        ret = spufs_rmdir(dir, dentry);
         WARN_ON(ret);
-        up(&dir->i_sem);
+
         return dcache_dir_close(inode, file);
 }