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[Qemu-block] [PULL v3 10/35] qcow2: get rid of qcow2_backing_read1 routi
From: |
Kevin Wolf |
Subject: |
[Qemu-block] [PULL v3 10/35] qcow2: get rid of qcow2_backing_read1 routine |
Date: |
Fri, 22 Dec 2017 16:18:21 +0100 |
From: Edgar Kaziakhmedov <address@hidden>
Since bdrv_co_preadv does all neccessary checks including
reading after the end of the backing file, avoid duplication
of verification before bdrv_co_preadv call.
Signed-off-by: Edgar Kaziakhmedov <address@hidden>
Reviewed-by: Vladimir Sementsov-Ogievskiy <address@hidden>
Reviewed-by: Eric Blake <address@hidden>
Signed-off-by: Kevin Wolf <address@hidden>
---
block/qcow2.h | 3 ---
block/qcow2.c | 51 ++++++++-------------------------------------------
2 files changed, 8 insertions(+), 46 deletions(-)
diff --git a/block/qcow2.h b/block/qcow2.h
index 6f0ff15dd0..46c8cf44ec 100644
--- a/block/qcow2.h
+++ b/block/qcow2.h
@@ -528,9 +528,6 @@ uint32_t offset_to_reftable_index(BDRVQcow2State *s,
uint64_t offset)
}
/* qcow2.c functions */
-int qcow2_backing_read1(BlockDriverState *bs, QEMUIOVector *qiov,
- int64_t sector_num, int nb_sectors);
-
int64_t qcow2_refcount_metadata_size(int64_t clusters, size_t cluster_size,
int refcount_order, bool
generous_increase,
uint64_t *refblock_count);
diff --git a/block/qcow2.c b/block/qcow2.c
index 1914a940e5..4348b2c0c5 100644
--- a/block/qcow2.c
+++ b/block/qcow2.c
@@ -1672,34 +1672,12 @@ static int64_t coroutine_fn
qcow2_co_get_block_status(BlockDriverState *bs,
return status;
}
-/* handle reading after the end of the backing file */
-int qcow2_backing_read1(BlockDriverState *bs, QEMUIOVector *qiov,
- int64_t offset, int bytes)
-{
- uint64_t bs_size = bs->total_sectors * BDRV_SECTOR_SIZE;
- int n1;
-
- if ((offset + bytes) <= bs_size) {
- return bytes;
- }
-
- if (offset >= bs_size) {
- n1 = 0;
- } else {
- n1 = bs_size - offset;
- }
-
- qemu_iovec_memset(qiov, n1, 0, bytes - n1);
-
- return n1;
-}
-
static coroutine_fn int qcow2_co_preadv(BlockDriverState *bs, uint64_t offset,
uint64_t bytes, QEMUIOVector *qiov,
int flags)
{
BDRVQcow2State *s = bs->opaque;
- int offset_in_cluster, n1;
+ int offset_in_cluster;
int ret;
unsigned int cur_bytes; /* number of bytes in current iteration */
uint64_t cluster_offset = 0;
@@ -1734,26 +1712,13 @@ static coroutine_fn int
qcow2_co_preadv(BlockDriverState *bs, uint64_t offset,
case QCOW2_CLUSTER_UNALLOCATED:
if (bs->backing) {
- /* read from the base image */
- n1 = qcow2_backing_read1(bs->backing->bs, &hd_qiov,
- offset, cur_bytes);
- if (n1 > 0) {
- QEMUIOVector local_qiov;
-
- qemu_iovec_init(&local_qiov, hd_qiov.niov);
- qemu_iovec_concat(&local_qiov, &hd_qiov, 0, n1);
-
- BLKDBG_EVENT(bs->file, BLKDBG_READ_BACKING_AIO);
- qemu_co_mutex_unlock(&s->lock);
- ret = bdrv_co_preadv(bs->backing, offset, n1,
- &local_qiov, 0);
- qemu_co_mutex_lock(&s->lock);
-
- qemu_iovec_destroy(&local_qiov);
-
- if (ret < 0) {
- goto fail;
- }
+ BLKDBG_EVENT(bs->file, BLKDBG_READ_BACKING_AIO);
+ qemu_co_mutex_unlock(&s->lock);
+ ret = bdrv_co_preadv(bs->backing, offset, cur_bytes,
+ &hd_qiov, 0);
+ qemu_co_mutex_lock(&s->lock);
+ if (ret < 0) {
+ goto fail;
}
} else {
/* Note: in this case, no need to wait */
--
2.13.6
- [Qemu-block] [PULL v3 00/35] Block layer patches, Kevin Wolf, 2017/12/22
- [Qemu-block] [PULL v3 01/35] block: Formats don't need CONSISTENT_READ with NO_IO, Kevin Wolf, 2017/12/22
- [Qemu-block] [PULL v3 02/35] iotests: fix 197 for vpc, Kevin Wolf, 2017/12/22
- [Qemu-block] [PULL v3 03/35] block: Make bdrv_drain_invoke() recursive, Kevin Wolf, 2017/12/22
- [Qemu-block] [PULL v3 04/35] block: Call .drain_begin only once in bdrv_drain_all_begin(), Kevin Wolf, 2017/12/22
- [Qemu-block] [PULL v3 05/35] test-bdrv-drain: Test BlockDriver callbacks for drain, Kevin Wolf, 2017/12/22
- [Qemu-block] [PULL v3 06/35] block: bdrv_drain_recurse(): Remove unused begin parameter, Kevin Wolf, 2017/12/22
- [Qemu-block] [PULL v3 07/35] block: Don't wait for requests in bdrv_drain*_end(), Kevin Wolf, 2017/12/22
- [Qemu-block] [PULL v3 08/35] block: Unify order in drain functions, Kevin Wolf, 2017/12/22
- [Qemu-block] [PULL v3 09/35] block: Don't acquire AioContext in hmp_qemu_io(), Kevin Wolf, 2017/12/22
- [Qemu-block] [PULL v3 10/35] qcow2: get rid of qcow2_backing_read1 routine,
Kevin Wolf <=
- [Qemu-block] [PULL v3 11/35] block: Document that x-blockdev-change breaks quorum children list, Kevin Wolf, 2017/12/22
- [Qemu-block] [PULL v3 13/35] block: Open backing image in force share mode for size probe, Kevin Wolf, 2017/12/22
- [Qemu-block] [PULL v3 14/35] block: Remove the obsolete -drive boot=on|off parameter, Kevin Wolf, 2017/12/22
- [Qemu-block] [PULL v3 12/35] nvme: Add tracing, Kevin Wolf, 2017/12/22
- [Qemu-block] [PULL v3 15/35] block: Remove the deprecated -hdachs option, Kevin Wolf, 2017/12/22
- [Qemu-block] [PULL v3 19/35] block: Make bdrv_drain() driver callbacks non-recursive, Kevin Wolf, 2017/12/22
- [Qemu-block] [PULL v3 17/35] block: Remove unused bdrv_requests_pending, Kevin Wolf, 2017/12/22
- [Qemu-block] [PULL v3 16/35] block: Mention -drive cyls/heads/secs/trans/serial/addr in deprecation chapter, Kevin Wolf, 2017/12/22
- [Qemu-block] [PULL v3 20/35] test-bdrv-drain: Test callback for bdrv_drain, Kevin Wolf, 2017/12/22
- [Qemu-block] [PULL v3 18/35] block: Assert drain_all is only called from main AioContext, Kevin Wolf, 2017/12/22