| From f3ba81ab59dcb21f79cf2f2053206d6b03431658 Mon Sep 17 00:00:00 2001 |
| Message-Id: <f3ba81ab59dcb21f79cf2f2053206d6b03431658.1389014116.git.minovotn@redhat.com> |
| In-Reply-To: <c8cc35838d42aa286242772d97e3a9be7bb786ba.1389014116.git.minovotn@redhat.com> |
| References: <c8cc35838d42aa286242772d97e3a9be7bb786ba.1389014116.git.minovotn@redhat.com> |
| From: Paolo Bonzini <pbonzini@redhat.com> |
| Date: Mon, 9 Dec 2013 14:09:03 +0100 |
| Subject: [PATCH 15/50] block: honour BlockLimits in bdrv_co_discard |
| |
| RH-Author: Paolo Bonzini <pbonzini@redhat.com> |
| Message-id: <1386598178-11845-18-git-send-email-pbonzini@redhat.com> |
| Patchwork-id: 56053 |
| O-Subject: [RHEL 7.0 qemu-kvm PATCH 17/52] block: honour BlockLimits in bdrv_co_discard |
| Bugzilla: 1007815 |
| RH-Acked-by: Jeffrey Cody <jcody@redhat.com> |
| RH-Acked-by: Fam Zheng <famz@redhat.com> |
| RH-Acked-by: Stefan Hajnoczi <stefanha@redhat.com> |
| |
| From: Peter Lieven <pl@kamp.de> |
| |
| Reviewed-by: Eric Blake <eblake@redhat.com> |
| Signed-off-by: Peter Lieven <pl@kamp.de> |
| Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> |
| (cherry picked from commit 6f14da5247076bde1e00444f6d5b2b7ca8075a09) |
| |
| block.c | 37 ++++++++++++++++++++++++++++++++++++- |
| 1 file changed, 36 insertions(+), 1 deletion(-) |
| |
| Signed-off-by: Michal Novotny <minovotn@redhat.com> |
| |
| block.c | 37 ++++++++++++++++++++++++++++++++++++- |
| 1 file changed, 36 insertions(+), 1 deletion(-) |
| |
| diff --git a/block.c b/block.c |
| index 2ed9aa9..23dbafd 100644 |
| |
| |
| @@ -4424,6 +4424,11 @@ static void coroutine_fn bdrv_discard_co_entry(void *opaque) |
| rwco->ret = bdrv_co_discard(rwco->bs, rwco->sector_num, rwco->nb_sectors); |
| } |
| |
| +/* if no limit is specified in the BlockLimits use a default |
| + * of 32768 512-byte sectors (16 MiB) per request. |
| + */ |
| +#define MAX_DISCARD_DEFAULT 32768 |
| + |
| int coroutine_fn bdrv_co_discard(BlockDriverState *bs, int64_t sector_num, |
| int nb_sectors) |
| { |
| @@ -4445,7 +4450,37 @@ int coroutine_fn bdrv_co_discard(BlockDriverState *bs, int64_t sector_num, |
| } |
| |
| if (bs->drv->bdrv_co_discard) { |
| - return bs->drv->bdrv_co_discard(bs, sector_num, nb_sectors); |
| + int max_discard = bs->bl.max_discard ? |
| + bs->bl.max_discard : MAX_DISCARD_DEFAULT; |
| + |
| + while (nb_sectors > 0) { |
| + int ret; |
| + int num = nb_sectors; |
| + |
| + /* align request */ |
| + if (bs->bl.discard_alignment && |
| + num >= bs->bl.discard_alignment && |
| + sector_num % bs->bl.discard_alignment) { |
| + if (num > bs->bl.discard_alignment) { |
| + num = bs->bl.discard_alignment; |
| + } |
| + num -= sector_num % bs->bl.discard_alignment; |
| + } |
| + |
| + /* limit request size */ |
| + if (num > max_discard) { |
| + num = max_discard; |
| + } |
| + |
| + ret = bs->drv->bdrv_co_discard(bs, sector_num, num); |
| + if (ret) { |
| + return ret; |
| + } |
| + |
| + sector_num += num; |
| + nb_sectors -= num; |
| + } |
| + return 0; |
| } else if (bs->drv->bdrv_aio_discard) { |
| BlockDriverAIOCB *acb; |
| CoroutineIOCompletion co = { |
| -- |
| 1.7.11.7 |
| |