summaryrefslogtreecommitdiff
path: root/drivers/md/dm-bufio.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/md/dm-bufio.c')
-rw-r--r--drivers/md/dm-bufio.c36
1 files changed, 34 insertions, 2 deletions
diff --git a/drivers/md/dm-bufio.c b/drivers/md/dm-bufio.c
index 54bdd923316f..9ed42125514b 100644
--- a/drivers/md/dm-bufio.c
+++ b/drivers/md/dm-bufio.c
@@ -104,6 +104,8 @@ struct dm_bufio_client {
struct list_head reserved_buffers;
unsigned need_reserved_buffers;
+ unsigned minimum_buffers;
+
struct hlist_head *cache_hash;
wait_queue_head_t free_buffer_wait;
@@ -861,8 +863,8 @@ static void __get_memory_limit(struct dm_bufio_client *c,
buffers = dm_bufio_cache_size_per_client >>
(c->sectors_per_block_bits + SECTOR_SHIFT);
- if (buffers < DM_BUFIO_MIN_BUFFERS)
- buffers = DM_BUFIO_MIN_BUFFERS;
+ if (buffers < c->minimum_buffers)
+ buffers = c->minimum_buffers;
*limit_buffers = buffers;
*threshold_buffers = buffers * DM_BUFIO_WRITEBACK_PERCENT / 100;
@@ -1350,6 +1352,34 @@ retry:
}
EXPORT_SYMBOL_GPL(dm_bufio_release_move);
+/*
+ * Free the given buffer.
+ *
+ * This is just a hint, if the buffer is in use or dirty, this function
+ * does nothing.
+ */
+void dm_bufio_forget(struct dm_bufio_client *c, sector_t block)
+{
+ struct dm_buffer *b;
+
+ dm_bufio_lock(c);
+
+ b = __find(c, block);
+ if (b && likely(!b->hold_count) && likely(!b->state)) {
+ __unlink_buffer(b);
+ __free_buffer_wake(b);
+ }
+
+ dm_bufio_unlock(c);
+}
+EXPORT_SYMBOL(dm_bufio_forget);
+
+void dm_bufio_set_minimum_buffers(struct dm_bufio_client *c, unsigned n)
+{
+ c->minimum_buffers = n;
+}
+EXPORT_SYMBOL(dm_bufio_set_minimum_buffers);
+
unsigned dm_bufio_get_block_size(struct dm_bufio_client *c)
{
return c->block_size;
@@ -1546,6 +1576,8 @@ struct dm_bufio_client *dm_bufio_client_create(struct block_device *bdev, unsign
INIT_LIST_HEAD(&c->reserved_buffers);
c->need_reserved_buffers = reserved_buffers;
+ c->minimum_buffers = DM_BUFIO_MIN_BUFFERS;
+
init_waitqueue_head(&c->free_buffer_wait);
c->async_write_error = 0;