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authorLinus Torvalds <torvalds@linux-foundation.org>2012-12-17 13:39:11 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2012-12-17 13:39:11 -0800
commit9228ff90387e276ad67b10c0eb525c9d6a57d5e9 (patch)
treee7c87b68daba7cf7ca4c342c6b52165bd78fbe16 /drivers/block/loop.c
parent9360b53661a2c7754517b2925580055bacc8ec38 (diff)
parentd2ec180c23a5a1bfe34d8638b0342a47c00cf70f (diff)
Merge branch 'for-3.8/drivers' of git://git.kernel.dk/linux-block
Pull block driver update from Jens Axboe: "Now that the core bits are in, here are the driver bits for 3.8. The branch contains: - A huge pile of drbd bits that were dumped from the 3.7 merge window. Following that, it was both made perfectly clear that there is going to be no more over-the-wall pulls and how the situation on individual pulls can be improved. - A few cleanups from Akinobu Mita for drbd and cciss. - Queue improvement for loop from Lukas. This grew into adding a generic interface for waiting/checking an even with a specific lock, allowing this to be pulled out of md and now loop and drbd is also using it. - A few fixes for xen back/front block driver from Roger Pau Monne. - Partition improvements from Stephen Warren, allowing partiion UUID to be used as an identifier." * 'for-3.8/drivers' of git://git.kernel.dk/linux-block: (609 commits) drbd: update Kconfig to match current dependencies drbd: Fix drbdsetup wait-connect, wait-sync etc... commands drbd: close race between drbd_set_role and drbd_connect drbd: respect no-md-barriers setting also when changed online via disk-options drbd: Remove obsolete check drbd: fixup after wait_even_lock_irq() addition to generic code loop: Limit the number of requests in the bio list wait: add wait_event_lock_irq() interface xen-blkfront: free allocated page xen-blkback: move free persistent grants code block: partition: msdos: provide UUIDs for partitions init: reduce PARTUUID min length to 1 from 36 block: store partition_meta_info.uuid as a string cciss: use check_signature() cciss: cleanup bitops usage drbd: use copy_highpage drbd: if the replication link breaks during handshake, keep retrying drbd: check return of kmalloc in receive_uuids drbd: Broadcast sync progress no more often than once per second drbd: don't try to clear bits once the disk has failed ...
Diffstat (limited to 'drivers/block/loop.c')
-rw-r--r--drivers/block/loop.c10
1 files changed, 10 insertions, 0 deletions
diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index 54046e51160a..ae1251270624 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -463,6 +463,7 @@ out:
*/
static void loop_add_bio(struct loop_device *lo, struct bio *bio)
{
+ lo->lo_bio_count++;
bio_list_add(&lo->lo_bio_list, bio);
}
@@ -471,6 +472,7 @@ static void loop_add_bio(struct loop_device *lo, struct bio *bio)
*/
static struct bio *loop_get_bio(struct loop_device *lo)
{
+ lo->lo_bio_count--;
return bio_list_pop(&lo->lo_bio_list);
}
@@ -489,6 +491,10 @@ static void loop_make_request(struct request_queue *q, struct bio *old_bio)
goto out;
if (unlikely(rw == WRITE && (lo->lo_flags & LO_FLAGS_READ_ONLY)))
goto out;
+ if (lo->lo_bio_count >= q->nr_congestion_on)
+ wait_event_lock_irq(lo->lo_req_wait,
+ lo->lo_bio_count < q->nr_congestion_off,
+ lo->lo_lock);
loop_add_bio(lo, old_bio);
wake_up(&lo->lo_event);
spin_unlock_irq(&lo->lo_lock);
@@ -546,6 +552,8 @@ static int loop_thread(void *data)
continue;
spin_lock_irq(&lo->lo_lock);
bio = loop_get_bio(lo);
+ if (lo->lo_bio_count < lo->lo_queue->nr_congestion_off)
+ wake_up(&lo->lo_req_wait);
spin_unlock_irq(&lo->lo_lock);
BUG_ON(!bio);
@@ -873,6 +881,7 @@ static int loop_set_fd(struct loop_device *lo, fmode_t mode,
lo->transfer = transfer_none;
lo->ioctl = NULL;
lo->lo_sizelimit = 0;
+ lo->lo_bio_count = 0;
lo->old_gfp_mask = mapping_gfp_mask(mapping);
mapping_set_gfp_mask(mapping, lo->old_gfp_mask & ~(__GFP_IO|__GFP_FS));
@@ -1673,6 +1682,7 @@ static int loop_add(struct loop_device **l, int i)
lo->lo_number = i;
lo->lo_thread = NULL;
init_waitqueue_head(&lo->lo_event);
+ init_waitqueue_head(&lo->lo_req_wait);
spin_lock_init(&lo->lo_lock);
disk->major = LOOP_MAJOR;
disk->first_minor = i << part_shift;