dm: tidy dm_suspend
Tidy dm_suspend function
- change return value logic in dm_suspend
- use atomic_read only once.
- move DMF_BLOCK_IO clearing into one place
Signed-off-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index c1ad7d7..5191954 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -1270,6 +1270,8 @@
if (__split_bio(md, c))
bio_io_error(c);
}
+
+ clear_bit(DMF_BLOCK_IO, &md->flags);
}
static void __merge_pushback_list(struct mapped_device *md)
@@ -1355,14 +1357,16 @@
{
struct dm_table *map = NULL;
DECLARE_WAITQUEUE(wait, current);
- int r = -EINVAL;
+ int pending, r = 0;
int do_lockfs = suspend_flags & DM_SUSPEND_LOCKFS_FLAG ? 1 : 0;
int noflush = suspend_flags & DM_SUSPEND_NOFLUSH_FLAG ? 1 : 0;
mutex_lock(&md->suspend_lock);
- if (dm_suspended(md))
+ if (dm_suspended(md)) {
+ r = -EINVAL;
goto out_unlock;
+ }
map = dm_get_table(md);
@@ -1417,7 +1421,8 @@
set_current_state(TASK_INTERRUPTIBLE);
smp_mb();
- if (!atomic_read(&md->pending) || signal_pending(current))
+ pending = atomic_read(&md->pending);
+ if (!pending || signal_pending(current))
break;
io_schedule();
@@ -1431,12 +1436,12 @@
__merge_pushback_list(md);
/* were we interrupted ? */
- r = -EINTR;
- if (atomic_read(&md->pending)) {
- clear_bit(DMF_BLOCK_IO, &md->flags);
+ if (pending) {
__flush_deferred_io(md);
up_write(&md->io_lock);
+
unlock_fs(md);
+ r = -EINTR;
goto out; /* pushback list is already flushed, so skip flush */
}
up_write(&md->io_lock);
@@ -1445,8 +1450,6 @@
set_bit(DMF_SUSPENDED, &md->flags);
- r = 0;
-
flush_and_out:
if (r && noflush) {
/*
@@ -1490,8 +1493,6 @@
goto out;
down_write(&md->io_lock);
- clear_bit(DMF_BLOCK_IO, &md->flags);
-
__flush_deferred_io(md);
up_write(&md->io_lock);