From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:58829) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YXcAF-0003XI-P7 for qemu-devel@nongnu.org; Mon, 16 Mar 2015 17:03:09 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1YXcAB-0005nb-73 for qemu-devel@nongnu.org; Mon, 16 Mar 2015 17:03:07 -0400 Message-ID: <55074505.7040502@redhat.com> Date: Mon, 16 Mar 2015 17:03:01 -0400 From: John Snow MIME-Version: 1.0 References: <1426271419-8277-1-git-send-email-jsnow@redhat.com> <1426271419-8277-12-git-send-email-jsnow@redhat.com> <550743A2.40602@redhat.com> In-Reply-To: <550743A2.40602@redhat.com> Content-Type: text/plain; charset=iso-8859-15; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [2.4 PATCH v3 11/19] qmp: add block-dirty-bitmap-clear List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Max Reitz , qemu-block@nongnu.org Cc: kwolf@redhat.com, famz@redhat.com, qemu-devel@nongnu.org, armbru@redhat.com, vsementsov@parallels.com, stefanha@redhat.com On 03/16/2015 04:57 PM, Max Reitz wrote: > On 2015-03-13 at 14:30, John Snow wrote: >> Add bdrv_clear_dirty_bitmap and a matching QMP command, >> qmp_block_dirty_bitmap_clear that enables a user to reset >> the bitmap attached to a drive. >> >> This allows us to reset a bitmap in the event of a full >> drive backup. >> >> Signed-off-by: John Snow >> --- >> block.c | 8 ++++++++ >> blockdev.c | 34 ++++++++++++++++++++++++++++++++++ >> include/block/block.h | 1 + >> qapi/block-core.json | 14 ++++++++++++++ >> qmp-commands.hx | 29 +++++++++++++++++++++++++++++ >> 5 files changed, 86 insertions(+) >> >> diff --git a/block.c b/block.c >> index d276fdc..a98ff49 100644 >> --- a/block.c >> +++ b/block.c >> @@ -62,6 +62,7 @@ >> struct BdrvDirtyBitmap { >> HBitmap *bitmap; >> BdrvDirtyBitmap *successor; >> + int64_t size; >> char *name; >> bool disabled; >> QLIST_ENTRY(BdrvDirtyBitmap) list; >> @@ -5460,6 +5461,7 @@ BdrvDirtyBitmap >> *bdrv_create_dirty_bitmap(BlockDriverState *bs, >> } >> bitmap = g_new0(BdrvDirtyBitmap, 1); >> bitmap->bitmap = hbitmap_alloc(bitmap_size, >> ffs(sector_granularity) - 1); >> + bitmap->size = bitmap_size; >> bitmap->name = g_strdup(name); >> bitmap->disabled = false; >> QLIST_INSERT_HEAD(&bs->dirty_bitmaps, bitmap, list); >> @@ -5662,6 +5664,12 @@ void bdrv_reset_dirty_bitmap(BlockDriverState >> *bs, BdrvDirtyBitmap *bitmap, >> hbitmap_reset(bitmap->bitmap, cur_sector, nr_sectors); >> } >> +void bdrv_clear_dirty_bitmap(BdrvDirtyBitmap *bitmap) >> +{ >> + assert(bdrv_dirty_bitmap_enabled(bitmap)); >> + hbitmap_reset(bitmap->bitmap, 0, bitmap->size); >> +} >> + >> static void bdrv_set_dirty(BlockDriverState *bs, int64_t cur_sector, >> int nr_sectors) >> { >> diff --git a/blockdev.c b/blockdev.c >> index 361c7a4..cba9f2c 100644 >> --- a/blockdev.c >> +++ b/blockdev.c >> @@ -2051,6 +2051,40 @@ void qmp_block_dirty_bitmap_remove(const char >> *node, const char *name, >> aio_context_release(aio_context); >> } >> +/** >> + * Completely clear a bitmap, for the purposes of synchronizing a bitmap >> + * immediately after a full backup operation. >> + */ >> +void qmp_block_dirty_bitmap_clear(const char *node, const char *name, >> + Error **errp) >> +{ >> + AioContext *aio_context; >> + BdrvDirtyBitmap *bitmap; >> + BlockDriverState *bs; >> + >> + bitmap = block_dirty_bitmap_lookup(node, name, &bs, &aio_context, >> errp); >> + if (!bitmap || !bs) { > > Again, you need to release the AIO context here if you're not doing that > in block_dirty_bitmap_lookup() already. > > Max > OK. Inclined to fix that in lookup() as I should've to begin with and leave this patch as-is. --js >> + return; >> + } >> + >> + if (bdrv_dirty_bitmap_frozen(bitmap)) { >> + error_setg(errp, >> + "Bitmap '%s' is currently frozen and cannot be >> modified", >> + name); >> + goto out; >> + } else if (!bdrv_dirty_bitmap_enabled(bitmap)) { >> + error_setg(errp, >> + "Bitmap '%s' is currently disabled and cannot be >> cleared", >> + name); >> + goto out; >> + } >> + >> + bdrv_clear_dirty_bitmap(bitmap); >> + >> + out: >> + aio_context_release(aio_context); >> +} >> + >> int hmp_drive_del(Monitor *mon, const QDict *qdict, QObject **ret_data) >> { >> const char *id = qdict_get_str(qdict, "id"); >> diff --git a/include/block/block.h b/include/block/block.h >> index 3084b53..10442e0 100644 >> --- a/include/block/block.h >> +++ b/include/block/block.h >> @@ -479,6 +479,7 @@ void bdrv_set_dirty_bitmap(BlockDriverState *bs, >> BdrvDirtyBitmap *bitmap, >> int64_t cur_sector, int nr_sectors); >> void bdrv_reset_dirty_bitmap(BlockDriverState *bs, BdrvDirtyBitmap >> *bitmap, >> int64_t cur_sector, int nr_sectors); >> +void bdrv_clear_dirty_bitmap(BdrvDirtyBitmap *bitmap); >> void bdrv_dirty_iter_init(BlockDriverState *bs, >> BdrvDirtyBitmap *bitmap, struct >> HBitmapIter *hbi); >> void bdrv_set_dirty_iter(struct HBitmapIter *hbi, int64_t offset); >> diff --git a/qapi/block-core.json b/qapi/block-core.json >> index f012de2..50970c4 100644 >> --- a/qapi/block-core.json >> +++ b/qapi/block-core.json >> @@ -1023,6 +1023,20 @@ >> 'data': 'BlockDirtyBitmap' } >> ## >> +# @block-dirty-bitmap-clear >> +# >> +# Clear (reset) a dirty bitmap on the device >> +# >> +# Returns: nothing on success >> +# If @node is not a valid block device, DeviceNotFound >> +# If @name is not found, GenericError with an explanation >> +# >> +# Since 2.4 >> +## >> +{ 'command': 'block-dirty-bitmap-clear', >> + 'data': 'BlockDirtyBitmap' } >> + >> +## >> # @block_set_io_throttle: >> # >> # Change I/O throttle limits for a block drive. >> diff --git a/qmp-commands.hx b/qmp-commands.hx >> index 72ac72f..db95e89 100644 >> --- a/qmp-commands.hx >> +++ b/qmp-commands.hx >> @@ -1301,6 +1301,35 @@ Example: >> EQMP >> { >> + .name = "block-dirty-bitmap-clear", >> + .args_type = "node:B,name:s", >> + .mhandler.cmd_new = qmp_marshal_input_block_dirty_bitmap_clear, >> + }, >> + >> +SQMP >> + >> +block-dirty-bitmap-clear >> +------------------------ >> +Since 2.4 >> + >> +Reset the dirty bitmap associated with a node so that an incremental >> backup >> +from this point in time forward will only backup clusters modified >> after this >> +clear operation. >> + >> +Arguments: >> + >> +- "node": device/node on which to remove dirty bitmap (json-string) >> +- "name": name of the dirty bitmap to remove (json-string) >> + >> +Example: >> + >> +-> { "execute": "block-dirty-bitmap-clear", "arguments": { "node": >> "drive0", >> + "name": >> "bitmap0" } } >> +<- { "return": {} } >> + >> +EQMP >> + >> + { >> .name = "blockdev-snapshot-sync", >> .args_type = >> "device:s?,node-name:s?,snapshot-file:s,snapshot-node-name:s?,format:s?,mode:s?", >> >> .mhandler.cmd_new = qmp_marshal_input_blockdev_snapshot_sync, >