[PATCH] dm table: add target preresume
This patch adds a target preresume hook.
It is called before the targets are resumed and if it returns an error the
resume gets cancelled.
The crypt target will use this to indicate that it is unable to process I/O
because no encryption key has been supplied.
Signed-off-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c
index 75fe949..47412ae 100644
--- a/drivers/md/dm-table.c
+++ b/drivers/md/dm-table.c
@@ -939,9 +939,20 @@
return suspend_targets(t, 1);
}
-void dm_table_resume_targets(struct dm_table *t)
+int dm_table_resume_targets(struct dm_table *t)
{
- int i;
+ int i, r = 0;
+
+ for (i = 0; i < t->num_targets; i++) {
+ struct dm_target *ti = t->targets + i;
+
+ if (!ti->type->preresume)
+ continue;
+
+ r = ti->type->preresume(ti);
+ if (r)
+ return r;
+ }
for (i = 0; i < t->num_targets; i++) {
struct dm_target *ti = t->targets + i;
@@ -949,6 +960,8 @@
if (ti->type->resume)
ti->type->resume(ti);
}
+
+ return 0;
}
int dm_table_any_congested(struct dm_table *t, int bdi_bits)
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 883860c..aeb63a3 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -1360,7 +1360,9 @@
if (!map || !dm_table_get_size(map))
goto out;
- dm_table_resume_targets(map);
+ r = dm_table_resume_targets(map);
+ if (r)
+ goto out;
down_write(&md->io_lock);
clear_bit(DMF_BLOCK_IO, &md->flags);
diff --git a/drivers/md/dm.h b/drivers/md/dm.h
index fe701c4..a48ec5e 100644
--- a/drivers/md/dm.h
+++ b/drivers/md/dm.h
@@ -57,7 +57,7 @@
struct list_head *dm_table_get_devices(struct dm_table *t);
void dm_table_presuspend_targets(struct dm_table *t);
void dm_table_postsuspend_targets(struct dm_table *t);
-void dm_table_resume_targets(struct dm_table *t);
+int dm_table_resume_targets(struct dm_table *t);
int dm_table_any_congested(struct dm_table *t, int bdi_bits);
void dm_table_unplug_all(struct dm_table *t);
int dm_table_flush_all(struct dm_table *t);