xfs: cleanup uuid handling
The uuid table handling should not be part of a semi-generic uuid library
but in the XFS code using it, so move those bits to xfs_mount.c and
refactor the whole glob to make it a proper abstraction.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Felix Blyakher <felixb@sgi.com>
diff --git a/fs/xfs/xfs_mount.c b/fs/xfs/xfs_mount.c
index 92fedfc..b101990 100644
--- 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 @@
{ 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 @@
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 @@
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_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);
@@ -1780,29 +1845,6 @@
}
/*
- * 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
* fixup. Only the first superblock is updated.