[PATCH] dm table: add target flush

This patch adds support for a per-target dm_flush_fn method.  This is needed
to allow dm-loop to invalidate page cache mappings in response to BLKFLSBUF
ioctl commands.

Signed-off-by: Bryn Reeves <breeves@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>

1 files changed, 5 insertions, 0 deletions

diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c
index 4920998efeeb..05befa91807a 100644
--- a/drivers/md/dm-table.c
+++ b/drivers/md/dm-table.c
@@ -1001,6 +1001,11 @@ int dm_table_flush_all(struct dm_table *t)
 {
         struct list_head *d, *devices = dm_table_get_devices(t);
         int ret = 0;
+        unsigned i;
+
+        for (i = 0; i < t->num_targets; i++)
+                if (t->targets[i].type->flush)
+                        t->targets[i].type->flush(&t->targets[i]);
 
         for (d = devices->next; d != devices; d = d->next) {
                 struct dm_dev *dd = list_entry(d, struct dm_dev, list);