From e3c3ec950b2cfea7feb048a4d0dd730eb1aad663 Mon Sep 17 00:00:00 2001
From: Akinobu Mita <akinobu.mita@gmail.com>
Date: Fri, 17 Apr 2009 08:41:21 +0200
Subject: [PATCH] --- yaml --- r: 146941 b: refs/heads/master c:
 e686307fdc84f249490e6c9da92fcb2424491f14 h: refs/heads/master i:   146939:
 e1165b8e710d8155578c637a18140f84660012e9 v: v3

---
 [refs]                     |  2 +-
 trunk/drivers/block/loop.c | 26 +++++++-------------------
 trunk/include/linux/bio.h  |  2 +-
 trunk/include/linux/loop.h |  3 +--
 4 files changed, 10 insertions(+), 23 deletions(-)

diff --git a/[refs] b/[refs]
index 1abf49e93218..3b086741a6b5 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: e93b9fb7d85da4fd9d5171649e5ddcac1dd572bf
+refs/heads/master: e686307fdc84f249490e6c9da92fcb2424491f14
diff --git a/trunk/drivers/block/loop.c b/trunk/drivers/block/loop.c
index ddae80825899..9ca4bb014657 100644
--- a/trunk/drivers/block/loop.c
+++ b/trunk/drivers/block/loop.c
@@ -511,11 +511,7 @@ static int do_bio_filebacked(struct loop_device *lo, struct bio *bio)
  */
 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 void loop_add_bio(struct loop_device *lo, struct bio *bio)
  */
 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 @@ static int loop_thread(void *data)
 
 	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 @@ static int loop_set_fd(struct loop_device *lo, fmode_t mode,
 	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/trunk/include/linux/bio.h b/trunk/include/linux/bio.h
index 7b214fd672a2..f37ca8c726ba 100644
--- a/trunk/include/linux/bio.h
+++ b/trunk/include/linux/bio.h
@@ -506,7 +506,7 @@ static inline int bio_has_data(struct bio *bio)
 }
 
 /*
- * 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/trunk/include/linux/loop.h b/trunk/include/linux/loop.h
index 40725447f5e0..66c194e2d9b9 100644
--- a/trunk/include/linux/loop.h
+++ b/trunk/include/linux/loop.h
@@ -56,8 +56,7 @@ struct loop_device {
 	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;