From: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
To: qemu-block@nongnu.org
Cc: fam@euphon.net, kwolf@redhat.com, vsementsov@virtuozzo.com,
armbru@redhat.com, qemu-devel@nongnu.org, mreitz@redhat.com,
stefanha@redhat.com, den@openvz.org, jsnow@redhat.com
Subject: [Qemu-devel] [PATCH v3 7/7] block/backup: merge duplicated logic into backup_do_cow
Date: Sat, 10 Aug 2019 22:31:55 +0300 [thread overview]
Message-ID: <20190810193155.58637-8-vsementsov@virtuozzo.com> (raw)
In-Reply-To: <20190810193155.58637-1-vsementsov@virtuozzo.com>
backup_cow_with_offload and backup_cow_with_bounce_buffer contains a
lot of duplicated logic. Move it into backup_do_cow.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
block/backup.c | 97 ++++++++++++++++++++------------------------------
1 file changed, 38 insertions(+), 59 deletions(-)
diff --git a/block/backup.c b/block/backup.c
index 65f7212c85..0ac31c2760 100644
--- a/block/backup.c
+++ b/block/backup.c
@@ -104,87 +104,61 @@ static void cow_request_end(CowRequest *req)
* error occurred, return a negative error number
*
* @bounce_buffer is assumed to enough to store
- * MIN(BACKUP_MAX_BOUNCE_BUFFER, @end - @start) bytes
+ * MIN(BACKUP_MAX_BOUNCE_BUFFER, @bytes) bytes
*/
-static int coroutine_fn backup_cow_with_bounce_buffer(BackupBlockJob *job,
- int64_t start,
- int64_t end,
- bool is_write_notifier,
- bool *error_is_read,
- void *bounce_buffer)
+static int coroutine_fn backup_cow_with_bounce_buffer(
+ BackupBlockJob *job, int64_t offset, int64_t bytes,
+ BdrvRequestFlags read_flags, bool *error_is_read, void *bounce_buffer)
{
- int ret;
BlockBackend *blk = job->common.blk;
- int nbytes, remaining_bytes;
- int read_flags = is_write_notifier ? BDRV_REQ_NO_SERIALISING : 0;
-
- assert(QEMU_IS_ALIGNED(start, job->cluster_size));
- bdrv_reset_dirty_bitmap(job->copy_bitmap, start, end - start);
- nbytes = MIN(end - start, job->len - start);
-
- remaining_bytes = nbytes;
- while (remaining_bytes) {
- int chunk = MIN(BACKUP_MAX_BOUNCE_BUFFER, remaining_bytes);
+ while (bytes) {
+ int ret;
+ int chunk = MIN(BACKUP_MAX_BOUNCE_BUFFER, bytes);
- ret = blk_co_pread(blk, start, chunk, bounce_buffer, read_flags);
+ ret = blk_co_pread(blk, offset, chunk, bounce_buffer, read_flags);
if (ret < 0) {
- trace_backup_do_cow_read_fail(job, start, ret);
+ trace_backup_do_cow_read_fail(job, offset, ret);
if (error_is_read) {
*error_is_read = true;
}
- goto fail;
+ return ret;
}
- ret = blk_co_pwrite(job->target, start, chunk, bounce_buffer,
+ ret = blk_co_pwrite(job->target, offset, chunk, bounce_buffer,
job->write_flags);
if (ret < 0) {
- trace_backup_do_cow_write_fail(job, start, ret);
+ trace_backup_do_cow_write_fail(job, offset, ret);
if (error_is_read) {
*error_is_read = false;
}
- goto fail;
+ return ret;
}
- start += chunk;
- remaining_bytes -= chunk;
+ offset += chunk;
+ bytes -= chunk;
}
- return nbytes;
-fail:
- bdrv_set_dirty_bitmap(job->copy_bitmap, start, job->cluster_size);
- return ret;
-
+ return 0;
}
/* Copy range to target and return the bytes copied. If error occurred, return a
* negative error number. */
static int coroutine_fn backup_cow_with_offload(BackupBlockJob *job,
- int64_t start,
- int64_t end,
- bool is_write_notifier)
+ int64_t offset,
+ int64_t bytes,
+ BdrvRequestFlags read_flags)
{
int ret;
- int nr_clusters;
BlockBackend *blk = job->common.blk;
- int nbytes = MIN(end - start, job->len - start);
- int read_flags = is_write_notifier ? BDRV_REQ_NO_SERIALISING : 0;
-
- assert(end - start < INT_MAX);
- assert(QEMU_IS_ALIGNED(start, job->cluster_size));
- nr_clusters = DIV_ROUND_UP(nbytes, job->cluster_size);
- bdrv_reset_dirty_bitmap(job->copy_bitmap, start,
- job->cluster_size * nr_clusters);
- ret = blk_co_copy_range(blk, start, job->target, start, nbytes,
+
+ ret = blk_co_copy_range(blk, offset, job->target, offset, bytes,
read_flags, job->write_flags);
if (ret < 0) {
- trace_backup_do_cow_copy_range_fail(job, start, ret);
- bdrv_set_dirty_bitmap(job->copy_bitmap, start,
- job->cluster_size * nr_clusters);
- return ret;
+ trace_backup_do_cow_copy_range_fail(job, offset, ret);
}
- return nbytes;
+ return ret;
}
/*
@@ -268,6 +242,8 @@ static int coroutine_fn backup_do_cow(BackupBlockJob *job,
int64_t start, end; /* bytes */
void *bounce_buffer = NULL;
int64_t skip_bytes;
+ BdrvRequestFlags read_flags =
+ is_write_notifier ? BDRV_REQ_NO_SERIALISING : 0;
qemu_co_rwlock_rdlock(&job->flush_rwlock);
@@ -281,6 +257,7 @@ static int coroutine_fn backup_do_cow(BackupBlockJob *job,
while (start < end) {
int64_t dirty_end;
+ int64_t cur_bytes;
if (!bdrv_dirty_bitmap_get(job->copy_bitmap, start)) {
trace_backup_do_cow_skip(job, start);
@@ -304,10 +281,11 @@ static int coroutine_fn backup_do_cow(BackupBlockJob *job,
}
trace_backup_do_cow_process(job, start);
+ cur_bytes = MIN(dirty_end - start, job->len - start);
+ bdrv_reset_dirty_bitmap(job->copy_bitmap, start, dirty_end - start);
if (job->use_copy_range) {
- ret = backup_cow_with_offload(job, start, dirty_end,
- is_write_notifier);
+ ret = backup_cow_with_offload(job, start, cur_bytes, read_flags);
if (ret < 0) {
job->use_copy_range = false;
}
@@ -315,24 +293,25 @@ static int coroutine_fn backup_do_cow(BackupBlockJob *job,
if (!job->use_copy_range) {
if (!bounce_buffer) {
size_t len = MIN(BACKUP_MAX_BOUNCE_BUFFER,
- MAX(dirty_end - start, end - dirty_end));
+ MAX(cur_bytes,
+ end - start - cur_bytes));
bounce_buffer = blk_try_blockalign(job->common.blk, len);
}
- ret = backup_cow_with_bounce_buffer(job, start, dirty_end,
- is_write_notifier,
- error_is_read, bounce_buffer);
+ ret = backup_cow_with_bounce_buffer(job, start, cur_bytes,
+ read_flags, error_is_read,
+ bounce_buffer);
}
if (ret < 0) {
+ bdrv_set_dirty_bitmap(job->copy_bitmap, start, dirty_end - start);
break;
}
/* Publish progress, guest I/O counts as progress too. Note that the
* offset field is an opaque progress value, it is not a disk offset.
*/
- start += ret;
- job->bytes_read += ret;
- job_progress_update(&job->common.job, ret);
- ret = 0;
+ start += cur_bytes;
+ job->bytes_read += cur_bytes;
+ job_progress_update(&job->common.job, cur_bytes);
}
if (bounce_buffer) {
--
2.18.0
prev parent reply other threads:[~2019-08-10 19:34 UTC|newest]
Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-08-10 19:31 [Qemu-devel] [PATCH v3 0/7] backup improvements Vladimir Sementsov-Ogievskiy
2019-08-10 19:31 ` [Qemu-devel] [PATCH v3 1/7] block/backup: deal with zero detection Vladimir Sementsov-Ogievskiy
2019-08-10 19:31 ` [Qemu-devel] [PATCH v3 2/7] block/backup: refactor write_flags Vladimir Sementsov-Ogievskiy
2019-08-10 19:31 ` [Qemu-devel] [PATCH v3 3/7] block/io: handle alignment and max_transfer for copy_range Vladimir Sementsov-Ogievskiy
2019-08-12 14:48 ` Max Reitz
2019-08-20 15:18 ` Vladimir Sementsov-Ogievskiy
2019-08-10 19:31 ` [Qemu-devel] [PATCH v3 4/7] block/backup: drop handling of " Vladimir Sementsov-Ogievskiy
2019-08-10 19:31 ` [Qemu-devel] [PATCH v3 5/7] block/backup: fix backup_cow_with_offload for last cluster Vladimir Sementsov-Ogievskiy
2019-08-10 19:31 ` [Qemu-devel] [PATCH v3 6/7] block/backup: teach backup_cow_with_bounce_buffer to copy more at once Vladimir Sementsov-Ogievskiy
2019-08-12 15:10 ` Max Reitz
2019-08-12 15:47 ` Vladimir Sementsov-Ogievskiy
2019-08-12 16:11 ` Max Reitz
2019-08-12 16:37 ` Vladimir Sementsov-Ogievskiy
2019-08-13 14:14 ` Vladimir Sementsov-Ogievskiy
2019-08-13 14:23 ` Max Reitz
2019-08-13 14:39 ` Vladimir Sementsov-Ogievskiy
2019-08-13 14:57 ` Max Reitz
2019-08-13 15:00 ` Vladimir Sementsov-Ogievskiy
2019-08-13 15:02 ` Max Reitz
2019-08-13 15:32 ` Vladimir Sementsov-Ogievskiy
2019-08-13 16:30 ` Max Reitz
2019-08-13 16:45 ` Vladimir Sementsov-Ogievskiy
2019-08-13 16:51 ` Max Reitz
2019-08-10 19:31 ` Vladimir Sementsov-Ogievskiy [this message]
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