1 files changed, 45 insertions, 8 deletions

diff --git a/drivers/md/dm-bufio.c b/drivers/md/dm-bufio.c
index 173cbb20d10..d724459860d 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;
 
@@ -538,7 +540,7 @@ static void use_inline_bio(struct dm_buffer *b, int rw, sector_t block,
 	bio_init(&b->bio);
 	b->bio.bi_io_vec = b->bio_vec;
 	b->bio.bi_max_vecs = DM_BUFIO_INLINE_VECS;
-	b->bio.bi_sector = block << b->c->sectors_per_block_bits;
+	b->bio.bi_iter.bi_sector = block << b->c->sectors_per_block_bits;
 	b->bio.bi_bdev = b->c->bdev;
 	b->bio.bi_end_io = end_io;
 
@@ -605,9 +607,9 @@ static void write_endio(struct bio *bio, int error)
 
 	BUG_ON(!test_bit(B_WRITING, &b->state));
 
-	smp_mb__before_clear_bit();
+	smp_mb__before_atomic();
 	clear_bit(B_WRITING, &b->state);
-	smp_mb__after_clear_bit();
+	smp_mb__after_atomic();
 
 	wake_up_bit(&b->state, B_WRITING);
 }
@@ -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;
@@ -995,9 +997,9 @@ static void read_endio(struct bio *bio, int error)
 
 	BUG_ON(!test_bit(B_READING, &b->state));
 
-	smp_mb__before_clear_bit();
+	smp_mb__before_atomic();
 	clear_bit(B_READING, &b->state);
-	smp_mb__after_clear_bit();
+	smp_mb__after_atomic();
 
 	wake_up_bit(&b->state, B_READING);
 }
@@ -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;
@@ -1511,7 +1541,7 @@ struct dm_bufio_client *dm_bufio_client_create(struct block_device *bdev, unsign
 	BUG_ON(block_size < 1 << SECTOR_SHIFT ||
 	       (block_size & (block_size - 1)));
 
-	c = kmalloc(sizeof(*c), GFP_KERNEL);
+	c = kzalloc(sizeof(*c), GFP_KERNEL);
 	if (!c) {
 		r = -ENOMEM;
 		goto bad_client;
@@ -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;
 
@@ -1717,6 +1749,11 @@ static int __init dm_bufio_init(void)
 {
 	__u64 mem;
 
+	dm_bufio_allocated_kmem_cache = 0;
+	dm_bufio_allocated_get_free_pages = 0;
+	dm_bufio_allocated_vmalloc = 0;
+	dm_bufio_current_allocated = 0;
+
 	memset(&dm_bufio_caches, 0, sizeof dm_bufio_caches);
 	memset(&dm_bufio_cache_names, 0, sizeof dm_bufio_cache_names);