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Diffstat (limited to 'drivers/md')
-rw-r--r--drivers/md/dm-ioctl.c15
-rw-r--r--drivers/md/dm.c37
-rw-r--r--drivers/md/dm.h5
3 files changed, 50 insertions, 7 deletions
diff --git a/drivers/md/dm-ioctl.c b/drivers/md/dm-ioctl.c
index 3fd8f0e..4702f38 100644
--- a/drivers/md/dm-ioctl.c
+++ b/drivers/md/dm-ioctl.c
@@ -1189,6 +1189,21 @@ static int table_load(struct dm_ioctl *param, size_t param_size)
goto out;
}
+ /* Protect md->type against concurrent table loads. */
+ dm_lock_md_type(md);
+ if (dm_get_md_type(md) == DM_TYPE_NONE)
+ /* Initial table load: acquire type of table. */
+ dm_set_md_type(md, dm_table_get_type(t));
+ else if (dm_get_md_type(md) != dm_table_get_type(t)) {
+ DMWARN("can't change device type after initial table load.");
+ dm_table_destroy(t);
+ dm_unlock_md_type(md);
+ r = -EINVAL;
+ goto out;
+ }
+ dm_unlock_md_type(md);
+
+ /* stage inactive table */
down_write(&_hash_lock);
hc = dm_get_mdptr(md);
if (!hc || hc->md != md) {
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index f3cc5d9..345e94c 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -125,6 +125,10 @@ struct mapped_device {
unsigned long flags;
struct request_queue *queue;
+ unsigned type;
+ /* Protect type against concurrent access. */
+ struct mutex type_lock;
+
struct gendisk *disk;
char name[16];
@@ -1877,8 +1881,10 @@ static struct mapped_device *alloc_dev(int minor)
if (r < 0)
goto bad_minor;
+ md->type = DM_TYPE_NONE;
init_rwsem(&md->io_lock);
mutex_init(&md->suspend_lock);
+ mutex_init(&md->type_lock);
spin_lock_init(&md->deferred_lock);
spin_lock_init(&md->barrier_error_lock);
rwlock_init(&md->map_lock);
@@ -2130,6 +2136,30 @@ int dm_create(int minor, struct mapped_device **result)
return 0;
}
+/*
+ * Functions to manage md->type.
+ * All are required to hold md->type_lock.
+ */
+void dm_lock_md_type(struct mapped_device *md)
+{
+ mutex_lock(&md->type_lock);
+}
+
+void dm_unlock_md_type(struct mapped_device *md)
+{
+ mutex_unlock(&md->type_lock);
+}
+
+void dm_set_md_type(struct mapped_device *md, unsigned type)
+{
+ md->type = type;
+}
+
+unsigned dm_get_md_type(struct mapped_device *md)
+{
+ return md->type;
+}
+
static struct mapped_device *dm_find_md(dev_t dev)
{
struct mapped_device *md;
@@ -2440,13 +2470,6 @@ struct dm_table *dm_swap_table(struct mapped_device *md, struct dm_table *table)
goto out;
}
- /* cannot change the device type, once a table is bound */
- if (md->map &&
- (dm_table_get_type(md->map) != dm_table_get_type(table))) {
- DMWARN("can't change the device type after a table is bound");
- goto out;
- }
-
map = __bind(md, table, &limits);
out:
diff --git a/drivers/md/dm.h b/drivers/md/dm.h
index 8223671..1db7825 100644
--- a/drivers/md/dm.h
+++ b/drivers/md/dm.h
@@ -66,6 +66,11 @@ int dm_table_alloc_md_mempools(struct dm_table *t);
void dm_table_free_md_mempools(struct dm_table *t);
struct dm_md_mempools *dm_table_get_md_mempools(struct dm_table *t);
+void dm_lock_md_type(struct mapped_device *md);
+void dm_unlock_md_type(struct mapped_device *md);
+void dm_set_md_type(struct mapped_device *md, unsigned type);
+unsigned dm_get_md_type(struct mapped_device *md);
+
/*
* To check the return value from dm_table_find_target().
*/