diff options
| author | Wen Congyang <wency@cn.fujitsu.com> | 2015-09-08 11:28:33 +0800 |
|---|---|---|
| committer | Jeff Cody <jcody@redhat.com> | 2015-09-25 08:37:07 -0400 |
| commit | 06c3916b35a1cf6db548450a0cfb96983c33c82f (patch) | |
| tree | 25f33565d45bed4614ba63dbfc361f74ff153a13 | |
| parent | 9568b511c9f91c3d21ea3e83426d4ee7168c98bb (diff) | |
Backup: don't do copy-on-read in before_write_notifier
We will copy data in before_write_notifier to do backup.
It is a nested I/O request, so we cannot do copy-on-read.
The steps to reproduce it:
1. -drive copy-on-read=on,... // qemu option
2. drive_backup -f disk0 /path_to_backup.img // monitor command
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Tested-by: Jeff Cody <jcody@redhat.com>
Message-id: 1441682913-14320-3-git-send-email-wency@cn.fujitsu.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
| -rw-r--r-- | block/backup.c | 20 |
1 files changed, 14 insertions, 6 deletions
diff --git a/block/backup.c b/block/backup.c index 965654d521..5696431711 100644 --- a/block/backup.c +++ b/block/backup.c @@ -89,7 +89,8 @@ static void cow_request_end(CowRequest *req) static int coroutine_fn backup_do_cow(BlockDriverState *bs, int64_t sector_num, int nb_sectors, - bool *error_is_read) + bool *error_is_read, + bool is_write_notifier) { BackupBlockJob *job = (BackupBlockJob *)bs->job; CowRequest cow_request; @@ -129,8 +130,14 @@ static int coroutine_fn backup_do_cow(BlockDriverState *bs, iov.iov_len = n * BDRV_SECTOR_SIZE; qemu_iovec_init_external(&bounce_qiov, &iov, 1); - ret = bdrv_co_readv(bs, start * BACKUP_SECTORS_PER_CLUSTER, n, - &bounce_qiov); + if (is_write_notifier) { + ret = bdrv_co_no_copy_on_readv(bs, + start * BACKUP_SECTORS_PER_CLUSTER, + n, &bounce_qiov); + } else { + ret = bdrv_co_readv(bs, start * BACKUP_SECTORS_PER_CLUSTER, n, + &bounce_qiov); + } if (ret < 0) { trace_backup_do_cow_read_fail(job, start, ret); if (error_is_read) { @@ -190,7 +197,7 @@ static int coroutine_fn backup_before_write_notify( assert((req->offset & (BDRV_SECTOR_SIZE - 1)) == 0); assert((req->bytes & (BDRV_SECTOR_SIZE - 1)) == 0); - return backup_do_cow(req->bs, sector_num, nb_sectors, NULL); + return backup_do_cow(req->bs, sector_num, nb_sectors, NULL, true); } static void backup_set_speed(BlockJob *job, int64_t speed, Error **errp) @@ -303,7 +310,8 @@ static int coroutine_fn backup_run_incremental(BackupBlockJob *job) return ret; } ret = backup_do_cow(bs, cluster * BACKUP_SECTORS_PER_CLUSTER, - BACKUP_SECTORS_PER_CLUSTER, &error_is_read); + BACKUP_SECTORS_PER_CLUSTER, &error_is_read, + false); if ((ret < 0) && backup_error_action(job, error_is_read, -ret) == BLOCK_ERROR_ACTION_REPORT) { @@ -408,7 +416,7 @@ static void coroutine_fn backup_run(void *opaque) } /* FULL sync mode we copy the whole drive. */ ret = backup_do_cow(bs, start * BACKUP_SECTORS_PER_CLUSTER, - BACKUP_SECTORS_PER_CLUSTER, &error_is_read); + BACKUP_SECTORS_PER_CLUSTER, &error_is_read, false); if (ret < 0) { /* Depending on error action, fail now or retry cluster */ BlockErrorAction action = |