From b952b5589a36114e06201c0d2e82c293dbad2b1f Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Thu, 18 Oct 2012 16:49:28 +0200 Subject: mirror: add support for on-source-error/on-target-error Error management is important for mirroring; otherwise, an error on the target (even something as "innocent" as ENOSPC) requires to start again with a full copy. Similar to on_read_error/on_write_error, two separate knobs are provided for on_source_error (reads) and on_target_error (writes). The default is 'report' for both. The 'ignore' policy will leave the sector dirty, so that it will be retried later. Thus, it will not cause corruption. Signed-off-by: Paolo Bonzini Signed-off-by: Kevin Wolf --- block/mirror.c | 94 +++++++++++++++++++++++++++++++++++++++++++++------------- 1 file changed, 73 insertions(+), 21 deletions(-) (limited to 'block') diff --git a/block/mirror.c b/block/mirror.c index 6320f6a2e5..d6618a4b34 100644 --- a/block/mirror.c +++ b/block/mirror.c @@ -32,13 +32,28 @@ typedef struct MirrorBlockJob { RateLimit limit; BlockDriverState *target; MirrorSyncMode mode; + BlockdevOnError on_source_error, on_target_error; bool synced; bool should_complete; int64_t sector_num; uint8_t *buf; } MirrorBlockJob; -static int coroutine_fn mirror_iteration(MirrorBlockJob *s) +static BlockErrorAction mirror_error_action(MirrorBlockJob *s, bool read, + int error) +{ + s->synced = false; + if (read) { + return block_job_error_action(&s->common, s->common.bs, + s->on_source_error, true, error); + } else { + return block_job_error_action(&s->common, s->target, + s->on_target_error, false, error); + } +} + +static int coroutine_fn mirror_iteration(MirrorBlockJob *s, + BlockErrorAction *p_action) { BlockDriverState *source = s->common.bs; BlockDriverState *target = s->target; @@ -60,9 +75,21 @@ static int coroutine_fn mirror_iteration(MirrorBlockJob *s) trace_mirror_one_iteration(s, s->sector_num, nb_sectors); ret = bdrv_co_readv(source, s->sector_num, nb_sectors, &qiov); if (ret < 0) { - return ret; + *p_action = mirror_error_action(s, true, -ret); + goto fail; + } + ret = bdrv_co_writev(target, s->sector_num, nb_sectors, &qiov); + if (ret < 0) { + *p_action = mirror_error_action(s, false, -ret); + s->synced = false; + goto fail; } - return bdrv_co_writev(target, s->sector_num, nb_sectors, &qiov); + return 0; + +fail: + /* Try again later. */ + bdrv_set_dirty(source, s->sector_num, nb_sectors); + return ret; } static void coroutine_fn mirror_run(void *opaque) @@ -117,8 +144,9 @@ static void coroutine_fn mirror_run(void *opaque) cnt = bdrv_get_dirty_count(bs); if (cnt != 0) { - ret = mirror_iteration(s); - if (ret < 0) { + BlockErrorAction action = BDRV_ACTION_REPORT; + ret = mirror_iteration(s, &action); + if (ret < 0 && action == BDRV_ACTION_REPORT) { goto immediate_exit; } cnt = bdrv_get_dirty_count(bs); @@ -129,23 +157,25 @@ static void coroutine_fn mirror_run(void *opaque) trace_mirror_before_flush(s); ret = bdrv_flush(s->target); if (ret < 0) { - goto immediate_exit; - } - - /* We're out of the streaming phase. From now on, if the job - * is cancelled we will actually complete all pending I/O and - * report completion. This way, block-job-cancel will leave - * the target in a consistent state. - */ - s->common.offset = end * BDRV_SECTOR_SIZE; - if (!s->synced) { - block_job_ready(&s->common); - s->synced = true; + if (mirror_error_action(s, false, -ret) == BDRV_ACTION_REPORT) { + goto immediate_exit; + } + } else { + /* We're out of the streaming phase. From now on, if the job + * is cancelled we will actually complete all pending I/O and + * report completion. This way, block-job-cancel will leave + * the target in a consistent state. + */ + s->common.offset = end * BDRV_SECTOR_SIZE; + if (!s->synced) { + block_job_ready(&s->common); + s->synced = true; + } + + should_complete = s->should_complete || + block_job_is_cancelled(&s->common); + cnt = bdrv_get_dirty_count(bs); } - - should_complete = s->should_complete || - block_job_is_cancelled(&s->common); - cnt = bdrv_get_dirty_count(bs); } if (cnt == 0 && should_complete) { @@ -197,6 +227,7 @@ static void coroutine_fn mirror_run(void *opaque) immediate_exit: g_free(s->buf); bdrv_set_dirty_tracking(bs, false); + bdrv_iostatus_disable(s->target); if (s->should_complete && ret == 0) { if (bdrv_get_flags(s->target) != bdrv_get_flags(s->common.bs)) { bdrv_reopen(s->target, bdrv_get_flags(s->common.bs), NULL); @@ -219,6 +250,13 @@ static void mirror_set_speed(BlockJob *job, int64_t speed, Error **errp) ratelimit_set_speed(&s->limit, speed / BDRV_SECTOR_SIZE, SLICE_TIME); } +static void mirror_iostatus_reset(BlockJob *job) +{ + MirrorBlockJob *s = container_of(job, MirrorBlockJob, common); + + bdrv_iostatus_reset(s->target); +} + static void mirror_complete(BlockJob *job, Error **errp) { MirrorBlockJob *s = container_of(job, MirrorBlockJob, common); @@ -245,25 +283,39 @@ static BlockJobType mirror_job_type = { .instance_size = sizeof(MirrorBlockJob), .job_type = "mirror", .set_speed = mirror_set_speed, + .iostatus_reset= mirror_iostatus_reset, .complete = mirror_complete, }; void mirror_start(BlockDriverState *bs, BlockDriverState *target, int64_t speed, MirrorSyncMode mode, + BlockdevOnError on_source_error, + BlockdevOnError on_target_error, BlockDriverCompletionFunc *cb, void *opaque, Error **errp) { MirrorBlockJob *s; + if ((on_source_error == BLOCKDEV_ON_ERROR_STOP || + on_source_error == BLOCKDEV_ON_ERROR_ENOSPC) && + !bdrv_iostatus_is_enabled(bs)) { + error_set(errp, QERR_INVALID_PARAMETER, "on-source-error"); + return; + } + s = block_job_create(&mirror_job_type, bs, speed, cb, opaque, errp); if (!s) { return; } + s->on_source_error = on_source_error; + s->on_target_error = on_target_error; s->target = target; s->mode = mode; bdrv_set_dirty_tracking(bs, true); bdrv_set_enable_write_cache(s->target, true); + bdrv_set_on_error(s->target, on_target_error, on_target_error); + bdrv_iostatus_enable(s->target); s->common.co = qemu_coroutine_create(mirror_run); trace_mirror_start(bs, s, s->common.co, opaque); qemu_coroutine_enter(s->common.co, s); -- cgit v1.2.3