NTFS: Fix cluster (de)allocators to work when the runlist is NULL and more
importantly to take a locked runlist rather than them locking it
which leads to lock reversal.
Signed-off-by: Anton Altaparmakov <aia21@cantab.net>
diff --git a/fs/ntfs/lcnalloc.h b/fs/ntfs/lcnalloc.h
index 4cac1c0..e4d7fb9 100644
--- a/fs/ntfs/lcnalloc.h
+++ b/fs/ntfs/lcnalloc.h
@@ -43,13 +43,14 @@
const NTFS_CLUSTER_ALLOCATION_ZONES zone);
extern s64 __ntfs_cluster_free(struct inode *vi, const VCN start_vcn,
- s64 count, const BOOL is_rollback);
+ s64 count, const BOOL write_locked, const BOOL is_rollback);
/**
* ntfs_cluster_free - free clusters on an ntfs volume
* @vi: vfs inode whose runlist describes the clusters to free
* @start_vcn: vcn in the runlist of @vi at which to start freeing clusters
* @count: number of clusters to free or -1 for all clusters
+ * @write_locked: true if the runlist is locked for writing
*
* Free @count clusters starting at the cluster @start_vcn in the runlist
* described by the vfs inode @vi.
@@ -64,19 +65,19 @@
* Return the number of deallocated clusters (not counting sparse ones) on
* success and -errno on error.
*
- * Locking: - The runlist described by @vi must be unlocked on entry and is
- * unlocked on return.
- * - This function takes the runlist lock of @vi for reading and
- * sometimes for writing and sometimes modifies the runlist.
+ * Locking: - The runlist described by @vi must be locked on entry and is
+ * locked on return. Note if the runlist is locked for reading the
+ * lock may be dropped and reacquired. Note the runlist may be
+ * modified when needed runlist fragments need to be mapped.
* - The volume lcn bitmap must be unlocked on entry and is unlocked
* on return.
* - This function takes the volume lcn bitmap lock for writing and
* modifies the bitmap contents.
*/
static inline s64 ntfs_cluster_free(struct inode *vi, const VCN start_vcn,
- s64 count)
+ s64 count, const BOOL write_locked)
{
- return __ntfs_cluster_free(vi, start_vcn, count, FALSE);
+ return __ntfs_cluster_free(vi, start_vcn, count, write_locked, FALSE);
}
extern int ntfs_cluster_free_from_rl_nolock(ntfs_volume *vol,
@@ -93,8 +94,10 @@
*
* Return 0 on success and -errno on error.
*
- * Locking: This function takes the volume lcn bitmap lock for writing and
- * modifies the bitmap contents.
+ * Locking: - This function takes the volume lcn bitmap lock for writing and
+ * modifies the bitmap contents.
+ * - The caller must have locked the runlist @rl for reading or
+ * writing.
*/
static inline int ntfs_cluster_free_from_rl(ntfs_volume *vol,
const runlist_element *rl)