loop: use BIO list management functions
Now that the bio list management stuff is generic, convert loop to use
bio lists instead of its own private bio list implementation.
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index ddae808..9ca4bb0 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -511,11 +511,7 @@
*/
static void loop_add_bio(struct loop_device *lo, struct bio *bio)
{
- if (lo->lo_biotail) {
- lo->lo_biotail->bi_next = bio;
- lo->lo_biotail = bio;
- } else
- lo->lo_bio = lo->lo_biotail = bio;
+ bio_list_add(&lo->lo_bio_list, bio);
}
/*
@@ -523,16 +519,7 @@
*/
static struct bio *loop_get_bio(struct loop_device *lo)
{
- struct bio *bio;
-
- if ((bio = lo->lo_bio)) {
- if (bio == lo->lo_biotail)
- lo->lo_biotail = NULL;
- lo->lo_bio = bio->bi_next;
- bio->bi_next = NULL;
- }
-
- return bio;
+ return bio_list_pop(&lo->lo_bio_list);
}
static int loop_make_request(struct request_queue *q, struct bio *old_bio)
@@ -609,12 +596,13 @@
set_user_nice(current, -20);
- while (!kthread_should_stop() || lo->lo_bio) {
+ while (!kthread_should_stop() || !bio_list_empty(&lo->lo_bio_list)) {
wait_event_interruptible(lo->lo_event,
- lo->lo_bio || kthread_should_stop());
+ !bio_list_empty(&lo->lo_bio_list) ||
+ kthread_should_stop());
- if (!lo->lo_bio)
+ if (bio_list_empty(&lo->lo_bio_list))
continue;
spin_lock_irq(&lo->lo_lock);
bio = loop_get_bio(lo);
@@ -841,7 +829,7 @@
lo->old_gfp_mask = mapping_gfp_mask(mapping);
mapping_set_gfp_mask(mapping, lo->old_gfp_mask & ~(__GFP_IO|__GFP_FS));
- lo->lo_bio = lo->lo_biotail = NULL;
+ bio_list_init(&lo->lo_bio_list);
/*
* set queue make_request_fn, and add limits based on lower level
diff --git a/include/linux/bio.h b/include/linux/bio.h
index 7b214fd..f37ca8c 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -506,7 +506,7 @@
}
/*
- * BIO list managment for use by remapping drivers (e.g. DM or MD).
+ * BIO list management for use by remapping drivers (e.g. DM or MD) and loop.
*
* A bio_list anchors a singly-linked list of bios chained through the bi_next
* member of the bio. The bio_list also caches the last list member to allow
diff --git a/include/linux/loop.h b/include/linux/loop.h
index 4072544..66c194e 100644
--- a/include/linux/loop.h
+++ b/include/linux/loop.h
@@ -56,8 +56,7 @@
gfp_t old_gfp_mask;
spinlock_t lo_lock;
- struct bio *lo_bio;
- struct bio *lo_biotail;
+ struct bio_list lo_bio_list;
int lo_state;
struct mutex lo_ctl_mutex;
struct task_struct *lo_thread;