From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:58045) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Zw9hW-0001Nx-6n for qemu-devel@nongnu.org; Tue, 10 Nov 2015 09:15:12 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Zw9hR-0005Zc-Ms for qemu-devel@nongnu.org; Tue, 10 Nov 2015 09:15:10 -0500 Received: from mx1.redhat.com ([209.132.183.28]:34202) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Zw9hR-0005ZP-Dy for qemu-devel@nongnu.org; Tue, 10 Nov 2015 09:15:05 -0500 From: Stefan Hajnoczi Date: Tue, 10 Nov 2015 14:14:05 +0000 Message-Id: <1447164879-6756-11-git-send-email-stefanha@redhat.com> In-Reply-To: <1447164879-6756-1-git-send-email-stefanha@redhat.com> References: <1447164879-6756-1-git-send-email-stefanha@redhat.com> Subject: [Qemu-devel] [PULL 10/44] qapi: Add transaction support to block-dirty-bitmap operations List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Fam Zheng , Peter Maydell , John Snow , Stefan Hajnoczi From: John Snow This adds two qmp commands to transactions. block-dirty-bitmap-add allows you to create a bitmap simultaneously alongside a new full backup to accomplish a clean synchronization point. block-dirty-bitmap-clear allows you to reset a bitmap back to as-if it were new, which can also be used alongside a full backup to accomplish a clean synchronization point. Signed-off-by: John Snow Reviewed-by: Max Reitz Reviewed-by: Stefan Hajnoczi Reviewed-by: Eric Blake Signed-off-by: Stefan Hajnoczi Signed-off-by: Fam Zheng Message-id: 1446765200-3054-2-git-send-email-jsnow@redhat.com Signed-off-by: Stefan Hajnoczi --- block.c | 19 +++++++- blockdev.c | 114 +++++++++++++++++++++++++++++++++++++++++++++- docs/bitmaps.md | 6 +-- include/block/block.h | 1 - include/block/block_int.h | 3 ++ qapi-schema.json | 6 ++- 6 files changed, 139 insertions(+), 10 deletions(-) diff --git a/block.c b/block.c index e9f40dc..4ed7fce 100644 --- a/block.c +++ b/block.c @@ -3399,10 +3399,25 @@ void bdrv_reset_dirty_bitmap(BdrvDirtyBitmap *bitmap, hbitmap_reset(bitmap->bitmap, cur_sector, nr_sectors); } -void bdrv_clear_dirty_bitmap(BdrvDirtyBitmap *bitmap) +void bdrv_clear_dirty_bitmap(BdrvDirtyBitmap *bitmap, HBitmap **out) { assert(bdrv_dirty_bitmap_enabled(bitmap)); - hbitmap_reset_all(bitmap->bitmap); + if (!out) { + hbitmap_reset_all(bitmap->bitmap); + } else { + HBitmap *backup = bitmap->bitmap; + bitmap->bitmap = hbitmap_alloc(bitmap->size, + hbitmap_granularity(backup)); + *out = backup; + } +} + +void bdrv_undo_clear_dirty_bitmap(BdrvDirtyBitmap *bitmap, HBitmap *in) +{ + HBitmap *tmp = bitmap->bitmap; + assert(bdrv_dirty_bitmap_enabled(bitmap)); + bitmap->bitmap = in; + hbitmap_free(tmp); } void bdrv_set_dirty(BlockDriverState *bs, int64_t cur_sector, diff --git a/blockdev.c b/blockdev.c index 97be42f..f4dff8b 100644 --- a/blockdev.c +++ b/blockdev.c @@ -1831,6 +1831,106 @@ static void blockdev_backup_clean(BlkTransactionState *common) } } +typedef struct BlockDirtyBitmapState { + BlkTransactionState common; + BdrvDirtyBitmap *bitmap; + BlockDriverState *bs; + AioContext *aio_context; + HBitmap *backup; + bool prepared; +} BlockDirtyBitmapState; + +static void block_dirty_bitmap_add_prepare(BlkTransactionState *common, + Error **errp) +{ + Error *local_err = NULL; + BlockDirtyBitmapAdd *action; + BlockDirtyBitmapState *state = DO_UPCAST(BlockDirtyBitmapState, + common, common); + + action = common->action->block_dirty_bitmap_add; + /* AIO context taken and released within qmp_block_dirty_bitmap_add */ + qmp_block_dirty_bitmap_add(action->node, action->name, + action->has_granularity, action->granularity, + &local_err); + + if (!local_err) { + state->prepared = true; + } else { + error_propagate(errp, local_err); + } +} + +static void block_dirty_bitmap_add_abort(BlkTransactionState *common) +{ + BlockDirtyBitmapAdd *action; + BlockDirtyBitmapState *state = DO_UPCAST(BlockDirtyBitmapState, + common, common); + + action = common->action->block_dirty_bitmap_add; + /* Should not be able to fail: IF the bitmap was added via .prepare(), + * then the node reference and bitmap name must have been valid. + */ + if (state->prepared) { + qmp_block_dirty_bitmap_remove(action->node, action->name, &error_abort); + } +} + +static void block_dirty_bitmap_clear_prepare(BlkTransactionState *common, + Error **errp) +{ + BlockDirtyBitmapState *state = DO_UPCAST(BlockDirtyBitmapState, + common, common); + BlockDirtyBitmap *action; + + action = common->action->block_dirty_bitmap_clear; + state->bitmap = block_dirty_bitmap_lookup(action->node, + action->name, + &state->bs, + &state->aio_context, + errp); + if (!state->bitmap) { + return; + } + + if (bdrv_dirty_bitmap_frozen(state->bitmap)) { + error_setg(errp, "Cannot modify a frozen bitmap"); + return; + } else if (!bdrv_dirty_bitmap_enabled(state->bitmap)) { + error_setg(errp, "Cannot clear a disabled bitmap"); + return; + } + + bdrv_clear_dirty_bitmap(state->bitmap, &state->backup); + /* AioContext is released in .clean() */ +} + +static void block_dirty_bitmap_clear_abort(BlkTransactionState *common) +{ + BlockDirtyBitmapState *state = DO_UPCAST(BlockDirtyBitmapState, + common, common); + + bdrv_undo_clear_dirty_bitmap(state->bitmap, state->backup); +} + +static void block_dirty_bitmap_clear_commit(BlkTransactionState *common) +{ + BlockDirtyBitmapState *state = DO_UPCAST(BlockDirtyBitmapState, + common, common); + + hbitmap_free(state->backup); +} + +static void block_dirty_bitmap_clear_clean(BlkTransactionState *common) +{ + BlockDirtyBitmapState *state = DO_UPCAST(BlockDirtyBitmapState, + common, common); + + if (state->aio_context) { + aio_context_release(state->aio_context); + } +} + static void abort_prepare(BlkTransactionState *common, Error **errp) { error_setg(errp, "Transaction aborted using Abort action"); @@ -1872,6 +1972,18 @@ static const BdrvActionOps actions[] = { .abort = internal_snapshot_abort, .clean = internal_snapshot_clean, }, + [TRANSACTION_ACTION_KIND_BLOCK_DIRTY_BITMAP_ADD] = { + .instance_size = sizeof(BlockDirtyBitmapState), + .prepare = block_dirty_bitmap_add_prepare, + .abort = block_dirty_bitmap_add_abort, + }, + [TRANSACTION_ACTION_KIND_BLOCK_DIRTY_BITMAP_CLEAR] = { + .instance_size = sizeof(BlockDirtyBitmapState), + .prepare = block_dirty_bitmap_clear_prepare, + .commit = block_dirty_bitmap_clear_commit, + .abort = block_dirty_bitmap_clear_abort, + .clean = block_dirty_bitmap_clear_clean, + } }; /* @@ -2277,7 +2389,7 @@ void qmp_block_dirty_bitmap_clear(const char *node, const char *name, goto out; } - bdrv_clear_dirty_bitmap(bitmap); + bdrv_clear_dirty_bitmap(bitmap, NULL); out: aio_context_release(aio_context); diff --git a/docs/bitmaps.md b/docs/bitmaps.md index fa87f07..9fd8ea6 100644 --- a/docs/bitmaps.md +++ b/docs/bitmaps.md @@ -97,11 +97,7 @@ which is included at the end of this document. } ``` -## Transactions (Not yet implemented) - -* Transactional commands are forthcoming in a future version, - and are not yet available for use. This section serves as - documentation of intent for their design and usage. +## Transactions ### Justification diff --git a/include/block/block.h b/include/block/block.h index c8b40b7..92f6f6a 100644 --- a/include/block/block.h +++ b/include/block/block.h @@ -501,7 +501,6 @@ void bdrv_set_dirty_bitmap(BdrvDirtyBitmap *bitmap, int64_t cur_sector, int nr_sectors); void bdrv_reset_dirty_bitmap(BdrvDirtyBitmap *bitmap, int64_t cur_sector, int nr_sectors); -void bdrv_clear_dirty_bitmap(BdrvDirtyBitmap *bitmap); void bdrv_dirty_iter_init(BdrvDirtyBitmap *bitmap, struct HBitmapIter *hbi); void bdrv_set_dirty_iter(struct HBitmapIter *hbi, int64_t offset); int64_t bdrv_get_dirty_count(BdrvDirtyBitmap *bitmap); diff --git a/include/block/block_int.h b/include/block/block_int.h index 4a9f8ff..8076407 100644 --- a/include/block/block_int.h +++ b/include/block/block_int.h @@ -688,4 +688,7 @@ void blk_dev_resize_cb(BlockBackend *blk); void bdrv_set_dirty(BlockDriverState *bs, int64_t cur_sector, int nr_sectors); bool bdrv_requests_pending(BlockDriverState *bs); +void bdrv_clear_dirty_bitmap(BdrvDirtyBitmap *bitmap, HBitmap **out); +void bdrv_undo_clear_dirty_bitmap(BdrvDirtyBitmap *bitmap, HBitmap *in); + #endif /* BLOCK_INT_H */ diff --git a/qapi-schema.json b/qapi-schema.json index e18f14c..dbab843 100644 --- a/qapi-schema.json +++ b/qapi-schema.json @@ -1531,6 +1531,8 @@ # abort since 1.6 # blockdev-snapshot-internal-sync since 1.7 # blockdev-backup since 2.3 +# block-dirty-bitmap-add since 2.5 +# block-dirty-bitmap-clear since 2.5 ## { 'union': 'TransactionAction', 'data': { @@ -1538,7 +1540,9 @@ 'drive-backup': 'DriveBackup', 'blockdev-backup': 'BlockdevBackup', 'abort': 'Abort', - 'blockdev-snapshot-internal-sync': 'BlockdevSnapshotInternal' + 'blockdev-snapshot-internal-sync': 'BlockdevSnapshotInternal', + 'block-dirty-bitmap-add': 'BlockDirtyBitmapAdd', + 'block-dirty-bitmap-clear': 'BlockDirtyBitmap' } } ## -- 2.5.0