Merge branch 'for-linus' of git://neil.brown.name/md

[pandora-kernel.git] / fs / xfs / xfs_mount.c

diff --git a/fs/xfs/xfs_mount.c b/fs/xfs/xfs_mount.c
index 92fedfc..b101990 100644 (file)
--- a/fs/xfs/xfs_mount.c
+++ b/fs/xfs/xfs_mount.c
@@ -45,7 +45,6 @@
 #include "xfs_fsops.h"
 #include "xfs_utils.h"
 
-STATIC int     xfs_uuid_mount(xfs_mount_t *);
 STATIC void    xfs_unmountfs_wait(xfs_mount_t *);
 
 
@@ -121,6 +120,84 @@ static const struct {
     { sizeof(xfs_sb_t),                         0 }
 };
 
+static DEFINE_MUTEX(xfs_uuid_table_mutex);
+static int xfs_uuid_table_size;
+static uuid_t *xfs_uuid_table;
+
+/*
+ * See if the UUID is unique among mounted XFS filesystems.
+ * Mount fails if UUID is nil or a FS with the same UUID is already mounted.
+ */
+STATIC int
+xfs_uuid_mount(
+       struct xfs_mount        *mp)
+{
+       uuid_t                  *uuid = &mp->m_sb.sb_uuid;
+       int                     hole, i;
+
+       if (mp->m_flags & XFS_MOUNT_NOUUID)
+               return 0;
+
+       if (uuid_is_nil(uuid)) {
+               cmn_err(CE_WARN,
+                       "XFS: Filesystem %s has nil UUID - can't mount",
+                       mp->m_fsname);
+               return XFS_ERROR(EINVAL);
+       }
+
+       mutex_lock(&xfs_uuid_table_mutex);
+       for (i = 0, hole = -1; i < xfs_uuid_table_size; i++) {
+               if (uuid_is_nil(&xfs_uuid_table[i])) {
+                       hole = i;
+                       continue;
+               }
+               if (uuid_equal(uuid, &xfs_uuid_table[i]))
+                       goto out_duplicate;
+       }
+
+       if (hole < 0) {
+               xfs_uuid_table = kmem_realloc(xfs_uuid_table,
+                       (xfs_uuid_table_size + 1) * sizeof(*xfs_uuid_table),
+                       xfs_uuid_table_size  * sizeof(*xfs_uuid_table),
+                       KM_SLEEP);
+               hole = xfs_uuid_table_size++;
+       }
+       xfs_uuid_table[hole] = *uuid;
+       mutex_unlock(&xfs_uuid_table_mutex);
+
+       return 0;
+
+ out_duplicate:
+       mutex_unlock(&xfs_uuid_table_mutex);
+       cmn_err(CE_WARN, "XFS: Filesystem %s has duplicate UUID - can't mount",
+                        mp->m_fsname);
+       return XFS_ERROR(EINVAL);
+}
+
+STATIC void
+xfs_uuid_unmount(
+       struct xfs_mount        *mp)
+{
+       uuid_t                  *uuid = &mp->m_sb.sb_uuid;
+       int                     i;
+
+       if (mp->m_flags & XFS_MOUNT_NOUUID)
+               return;
+
+       mutex_lock(&xfs_uuid_table_mutex);
+       for (i = 0; i < xfs_uuid_table_size; i++) {
+               if (uuid_is_nil(&xfs_uuid_table[i]))
+                       continue;
+               if (!uuid_equal(uuid, &xfs_uuid_table[i]))
+                       continue;
+               memset(&xfs_uuid_table[i], 0, sizeof(uuid_t));
+               break;
+       }
+       ASSERT(i < xfs_uuid_table_size);
+       mutex_unlock(&xfs_uuid_table_mutex);
+}
+
+
 /*
  * Free up the resources associated with a mount structure.  Assume that
  * the structure was initially zeroed, so we can tell which fields got
@@ -962,18 +1039,9 @@ xfs_mountfs(
 
        mp->m_maxioffset = xfs_max_file_offset(sbp->sb_blocklog);
 
-       /*
-        * XFS uses the uuid from the superblock as the unique
-        * identifier for fsid.  We can not use the uuid from the volume
-        * since a single partition filesystem is identical to a single
-        * partition volume/filesystem.
-        */
-       if (!(mp->m_flags & XFS_MOUNT_NOUUID)) {
-               if (xfs_uuid_mount(mp)) {
-                       error = XFS_ERROR(EINVAL);
-                       goto out;
-               }
-       }
+       error = xfs_uuid_mount(mp);
+       if (error)
+               goto out;
 
        /*
         * Set the minimum read and write sizes
@@ -1192,8 +1260,7 @@ xfs_mountfs(
  out_free_perag:
        xfs_free_perag(mp);
  out_remove_uuid:
-       if (!(mp->m_flags & XFS_MOUNT_NOUUID))
-               uuid_table_remove(&mp->m_sb.sb_uuid);
+       xfs_uuid_unmount(mp);
  out:
        return error;
 }
@@ -1276,9 +1343,7 @@ xfs_unmountfs(
        xfs_unmountfs_wait(mp);                 /* wait for async bufs */
        xfs_log_unmount_write(mp);
        xfs_log_unmount(mp);
-
-       if ((mp->m_flags & XFS_MOUNT_NOUUID) == 0)
-               uuid_table_remove(&mp->m_sb.sb_uuid);
+       xfs_uuid_unmount(mp);
 
 #if defined(DEBUG)
        xfs_errortag_clearall(mp, 0);
@@ -1779,29 +1844,6 @@ xfs_freesb(
        mp->m_sb_bp = NULL;
 }
 
-/*
- * See if the UUID is unique among mounted XFS filesystems.
- * Mount fails if UUID is nil or a FS with the same UUID is already mounted.
- */
-STATIC int
-xfs_uuid_mount(
-       xfs_mount_t     *mp)
-{
-       if (uuid_is_nil(&mp->m_sb.sb_uuid)) {
-               cmn_err(CE_WARN,
-                       "XFS: Filesystem %s has nil UUID - can't mount",
-                       mp->m_fsname);
-               return -1;
-       }
-       if (!uuid_table_insert(&mp->m_sb.sb_uuid)) {
-               cmn_err(CE_WARN,
-                       "XFS: Filesystem %s has duplicate UUID - can't mount",
-                       mp->m_fsname);
-               return -1;
-       }
-       return 0;
-}
-
 /*
  * Used to log changes to the superblock unit and width fields which could
  * be altered by the mount options, as well as any potential sb_features2