Fam Zheng <f...@redhat.com> writes:
> This drops BlockDriverState.in_use with op_blockers:
>
> - Call bdrv_op_block_all in place of bdrv_set_in_use(bs, 1).
> - Call bdrv_op_unblock_all in place of bdrv_set_in_use(bs, 0).
> - Check bdrv_op_is_blocked() in place of bdrv_in_use(bs).
> The specific types are used, e.g. in place of starting block backup,
> bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_BACKUP, ...).
> - Check bdrv_op_blocker_is_empty() in place of assert(!bs->in_use).
>
> Note: there is only bdrv_op_block_all and bdrv_op_unblock_all callers at
> this moment. So although the checks are specific to op types, this
> changes can still be seen as identical logic with previously with
> in_use. The difference is error message are improved because of blocker
> error info.
>
> Signed-off-by: Fam Zheng <f...@redhat.com>
> Reviewed-by: Jeff Cody <jc...@redhat.com>
> ---
> block-migration.c | 7 +++++--
> block.c | 24 +++++++-----------------
> blockdev.c | 19 +++++++++----------
> blockjob.c | 14 +++++++++-----
> hw/block/dataplane/virtio-blk.c | 18 ++++++++++++------
> include/block/block.h | 2 --
> include/block/block_int.h | 1 -
> include/block/blockjob.h | 3 +++
> 8 files changed, 45 insertions(+), 43 deletions(-)
>
> diff --git a/block-migration.c b/block-migration.c
> index 56951e0..1656270 100644
> --- a/block-migration.c
> +++ b/block-migration.c
> @@ -59,6 +59,7 @@ typedef struct BlkMigDevState {
> unsigned long *aio_bitmap;
> int64_t completed_sectors;
> BdrvDirtyBitmap *dirty_bitmap;
> + Error *blocker;
> } BlkMigDevState;
>
> typedef struct BlkMigBlock {
> @@ -361,7 +362,8 @@ static void init_blk_migration_it(void *opaque,
> BlockDriverState *bs)
> bmds->completed_sectors = 0;
> bmds->shared_base = block_mig_state.shared_base;
> alloc_aio_bitmap(bmds);
> - bdrv_set_in_use(bs, 1);
> + error_setg(&bmds->blocker, "block device is in use by migration");
> + bdrv_op_block_all(bs, bmds->blocker);
> bdrv_ref(bs);
>
> block_mig_state.total_sector_sum += sectors;
Unlike QERR_DEVICE_IN_USE, this message doesn't include the device name.
Did you verify it's not needed to make sense of the message?
> @@ -599,7 +601,8 @@ static void blk_mig_cleanup(void)
> blk_mig_lock();
> while ((bmds = QSIMPLEQ_FIRST(&block_mig_state.bmds_list)) != NULL) {
> QSIMPLEQ_REMOVE_HEAD(&block_mig_state.bmds_list, entry);
> - bdrv_set_in_use(bmds->bs, 0);
> + bdrv_op_unblock_all(bmds->bs, bmds->blocker);
> + error_free(bmds->blocker);
> bdrv_unref(bmds->bs);
> g_free(bmds->aio_bitmap);
> g_free(bmds);
> diff --git a/block.c b/block.c
> index 32338ca..0747a43 100644
> --- a/block.c
> +++ b/block.c
> @@ -1904,7 +1904,6 @@ static void bdrv_move_feature_fields(BlockDriverState
> *bs_dest,
> bs_dest->refcnt = bs_src->refcnt;
>
> /* job */
> - bs_dest->in_use = bs_src->in_use;
> bs_dest->job = bs_src->job;
>
> /* keep the same entry in bdrv_states */
> @@ -1947,7 +1946,7 @@ void bdrv_swap(BlockDriverState *bs_new,
> BlockDriverState *bs_old)
> assert(QLIST_EMPTY(&bs_new->dirty_bitmaps));
> assert(bs_new->job == NULL);
> assert(bs_new->dev == NULL);
> - assert(bs_new->in_use == 0);
> + assert(bdrv_op_blocker_is_empty(bs_new));
> assert(bs_new->io_limits_enabled == false);
> assert(!throttle_have_timer(&bs_new->throttle_state));
>
> @@ -1966,7 +1965,7 @@ void bdrv_swap(BlockDriverState *bs_new,
> BlockDriverState *bs_old)
> /* Check a few fields that should remain attached to the device */
> assert(bs_new->dev == NULL);
> assert(bs_new->job == NULL);
> - assert(bs_new->in_use == 0);
> + assert(bdrv_op_blocker_is_empty(bs_new));
> assert(bs_new->io_limits_enabled == false);
> assert(!throttle_have_timer(&bs_new->throttle_state));
>
> @@ -2011,7 +2010,7 @@ static void bdrv_delete(BlockDriverState *bs)
> {
> assert(!bs->dev);
> assert(!bs->job);
> - assert(!bs->in_use);
> + assert(bdrv_op_blocker_is_empty(bs));
> assert(!bs->refcnt);
> assert(QLIST_EMPTY(&bs->dirty_bitmaps));
>
> @@ -2193,7 +2192,8 @@ int bdrv_commit(BlockDriverState *bs)
> return -ENOTSUP;
> }
>
> - if (bdrv_in_use(bs) || bdrv_in_use(bs->backing_hd)) {
> + if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_COMMIT, NULL) ||
> + bdrv_op_is_blocked(bs->backing_hd, BLOCK_OP_TYPE_COMMIT, NULL)) {
> return -EBUSY;
> }
>
> @@ -3446,8 +3446,9 @@ int bdrv_truncate(BlockDriverState *bs, int64_t offset)
> return -ENOTSUP;
> if (bs->read_only)
> return -EACCES;
> - if (bdrv_in_use(bs))
> + if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_RESIZE, NULL)) {
> return -EBUSY;
> + }
> ret = drv->bdrv_truncate(bs, offset);
> if (ret == 0) {
> ret = refresh_total_sectors(bs, offset >> BDRV_SECTOR_BITS);
> @@ -5344,17 +5345,6 @@ bool bdrv_op_blocker_is_empty(BlockDriverState *bs)
> return true;
> }
>
> -void bdrv_set_in_use(BlockDriverState *bs, int in_use)
> -{
> - assert(bs->in_use != in_use);
> - bs->in_use = in_use;
> -}
> -
> -int bdrv_in_use(BlockDriverState *bs)
> -{
> - return bs->in_use;
> -}
> -
> void bdrv_iostatus_enable(BlockDriverState *bs)
> {
> bs->iostatus_enabled = true;
> diff --git a/blockdev.c b/blockdev.c
> index 7810e9f..5d950fa 100644
> --- a/blockdev.c
> +++ b/blockdev.c
> @@ -1295,8 +1295,8 @@ static void
> external_snapshot_prepare(BlkTransactionState *common,
> return;
> }
>
> - if (bdrv_in_use(state->old_bs)) {
> - error_set(errp, QERR_DEVICE_IN_USE, device);
> + if (bdrv_op_is_blocked(state->old_bs,
> + BLOCK_OP_TYPE_EXTERNAL_SNAPSHOT, errp)) {
> return;
> }
>
> @@ -1518,8 +1518,7 @@ exit:
>
> static void eject_device(BlockDriverState *bs, int force, Error **errp)
> {
> - if (bdrv_in_use(bs)) {
> - error_set(errp, QERR_DEVICE_IN_USE, bdrv_get_device_name(bs));
> + if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_EJECT, errp)) {
> return;
> }
> if (!bdrv_dev_has_removable_media(bs)) {
> @@ -1721,14 +1720,16 @@ int do_drive_del(Monitor *mon, const QDict *qdict,
> QObject **ret_data)
> {
> const char *id = qdict_get_str(qdict, "id");
> BlockDriverState *bs;
> + Error *local_err = NULL;
>
> bs = bdrv_find(id);
> if (!bs) {
> qerror_report(QERR_DEVICE_NOT_FOUND, id);
> return -1;
> }
> - if (bdrv_in_use(bs)) {
> - qerror_report(QERR_DEVICE_IN_USE, id);
> + if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_DRIVE_DEL, &local_err)) {
> + error_report("%s", error_get_pretty(local_err));
> + error_free(local_err);
> return -1;
> }
>
> @@ -1984,8 +1985,7 @@ void qmp_drive_backup(const char *device, const char
> *target,
> }
> }
>
> - if (bdrv_in_use(bs)) {
> - error_set(errp, QERR_DEVICE_IN_USE, device);
> + if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_BACKUP_SOURCE, errp)) {
> return;
> }
>
> @@ -2118,8 +2118,7 @@ void qmp_drive_mirror(const char *device, const char
> *target,
> }
> }
>
> - if (bdrv_in_use(bs)) {
> - error_set(errp, QERR_DEVICE_IN_USE, device);
> + if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_MIRROR, errp)) {
> return;
> }
>
> diff --git a/blockjob.c b/blockjob.c
> index cd4784f..60e72f5 100644
> --- a/blockjob.c
> +++ b/blockjob.c
> @@ -41,14 +41,16 @@ void *block_job_create(const BlockJobDriver *driver,
> BlockDriverState *bs,
> {
> BlockJob *job;
>
> - if (bs->job || bdrv_in_use(bs)) {
> + if (bs->job || !bdrv_op_blocker_is_empty(bs)) {
> error_set(errp, QERR_DEVICE_IN_USE, bdrv_get_device_name(bs));
> return NULL;
> }
Elsewhere, you replace bdrv_in_use() by bdrv_op_is_blocked(). Why not
here?
Doesn't this contradict the commit message?
> bdrv_ref(bs);
> - bdrv_set_in_use(bs, 1);
> -
> job = g_malloc0(driver->instance_size);
> + error_setg(&job->blocker, "block device is in use by block job: %s",
> + BlockJobType_lookup[driver->job_type]);
> + bdrv_op_block_all(bs, job->blocker);
> +
> job->driver = driver;
> job->bs = bs;
> job->cb = cb;
[...]
