[PATCH] device-mapper snapshot: metadata reading separation

More snapshot metadata reading into separate function, to prepare for changing
the place it gets called from.

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>
This commit is contained in:
Alasdair G Kergon 2006-01-06 00:20:02 -08:00 committed by Linus Torvalds
parent 81f1777a55
commit 2d38fe2044

View File

@ -371,6 +371,20 @@ static inline ulong round_up(ulong n, ulong size)
return (n + size) & ~size;
}
static void read_snapshot_metadata(struct dm_snapshot *s)
{
if (s->have_metadata)
return;
if (s->store.read_metadata(&s->store)) {
down_write(&s->lock);
s->valid = 0;
up_write(&s->lock);
}
s->have_metadata = 1;
}
/*
* Construct a snapshot mapping: <origin_dev> <COW-dev> <p/n> <chunk-size>
*/
@ -848,16 +862,7 @@ static void snapshot_resume(struct dm_target *ti)
{
struct dm_snapshot *s = (struct dm_snapshot *) ti->private;
if (s->have_metadata)
return;
if (s->store.read_metadata(&s->store)) {
down_write(&s->lock);
s->valid = 0;
up_write(&s->lock);
}
s->have_metadata = 1;
read_snapshot_metadata(s);
}
static int snapshot_status(struct dm_target *ti, status_type_t type,