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>
This commit is contained in:
Milan Broz 2008-02-08 02:10:25 +00:00 committed by Alasdair G Kergon
parent 6d6f10df89
commit 73d410c013

View file

@ -1270,6 +1270,8 @@ static void __flush_deferred_io(struct mapped_device *md)
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 @@ int dm_suspend(struct mapped_device *md, unsigned suspend_flags)
{
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 @@ int dm_suspend(struct mapped_device *md, unsigned suspend_flags)
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 @@ int dm_suspend(struct mapped_device *md, unsigned suspend_flags)
__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 @@ int dm_suspend(struct mapped_device *md, unsigned suspend_flags)
set_bit(DMF_SUSPENDED, &md->flags);
r = 0;
flush_and_out:
if (r && noflush) {
/*
@ -1490,8 +1493,6 @@ int dm_resume(struct mapped_device *md)
goto out;
down_write(&md->io_lock);
clear_bit(DMF_BLOCK_IO, &md->flags);
__flush_deferred_io(md);
up_write(&md->io_lock);