From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:58675) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YLc9E-0007YH-6r for qemu-devel@nongnu.org; Wed, 11 Feb 2015 13:36:29 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1YLc9A-0004Jl-Ue for qemu-devel@nongnu.org; Wed, 11 Feb 2015 13:36:28 -0500 Received: from mx1.redhat.com ([209.132.183.28]:45404) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YLc9A-0004Jh-Mg for qemu-devel@nongnu.org; Wed, 11 Feb 2015 13:36:24 -0500 Message-ID: <54DBA126.5070602@redhat.com> Date: Wed, 11 Feb 2015 13:36:22 -0500 From: John Snow MIME-Version: 1.0 References: <1423532117-14490-1-git-send-email-jsnow@redhat.com> <1423532117-14490-9-git-send-email-jsnow@redhat.com> <54DB9F34.8090706@redhat.com> In-Reply-To: <54DB9F34.8090706@redhat.com> Content-Type: text/plain; charset=iso-8859-15; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH v12 08/17] qmp: add block-dirty-bitmap-clear List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Max Reitz , qemu-devel@nongnu.org Cc: kwolf@redhat.com, vsementsov@parallels.com, famz@redhat.com, armbru@redhat.com, stefanha@redhat.com On 02/11/2015 01:28 PM, Max Reitz wrote: > On 2015-02-09 at 20:35, 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 | 7 +++++++ >> blockdev.c | 31 +++++++++++++++++++++++++++++++ >> include/block/block.h | 1 + >> qapi/block-core.json | 14 ++++++++++++++ >> qmp-commands.hx | 24 ++++++++++++++++++++++++ >> 5 files changed, 77 insertions(+) >> >> diff --git a/block.c b/block.c >> index e93fceb..ad33d96 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; >> @@ -5422,6 +5423,7 @@ 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); >> @@ -5624,6 +5626,11 @@ void bdrv_reset_dirty_bitmap(BlockDriverState >> *bs, BdrvDirtyBitmap *bitmap, >> hbitmap_reset(bitmap->bitmap, cur_sector, nr_sectors); >> } >> +void bdrv_clear_dirty_bitmap(BdrvDirtyBitmap *bitmap) >> +{ >> + hbitmap_reset(bitmap->bitmap, 0, bitmap->size); >> +} > > Is it fine to use this function on frozen or disabled bitmaps? The QMP > interface at least suggests the former isn't, but I think the latter > shouldn't be either (which may be wrong, though). > Bug. This should be prohibited for frozen or disabled bitmaps, yes. >> + >> static void bdrv_set_dirty(BlockDriverState *bs, int64_t cur_sector, >> int nr_sectors) >> { >> diff --git a/blockdev.c b/blockdev.c >> index 3f41e82..83d0608 100644 >> --- a/blockdev.c >> +++ b/blockdev.c >> @@ -2116,6 +2116,37 @@ void qmp_block_dirty_bitmap_disable(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, errp); >> + if (!bitmap) { >> + return; >> + } >> + >> + aio_context = bdrv_get_aio_context(bs); >> + aio_context_acquire(aio_context); >> + >> + if (bdrv_dirty_bitmap_frozen(bitmap)) { >> + error_setg(errp, >> + "Bitmap '%s' is currently frozen and cannot be >> modified.\n", >> + name); >> + goto out; >> + } >> + bdrv_clear_dirty_bitmap(bitmap); >> + >> + out: >> + aio_context_release(aio_context); >> +} >> + >> int do_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 8589e77..8916ecd 100644 >> --- a/include/block/block.h >> +++ b/include/block/block.h >> @@ -467,6 +467,7 @@ 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 9c5a99c..702b76a 100644 >> --- a/qapi/block-core.json >> +++ b/qapi/block-core.json >> @@ -1050,6 +1050,20 @@ >> '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 2.3 >> +## >> +{ '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 5aa3845..e1d96cd 100644 >> --- a/qmp-commands.hx >> +++ b/qmp-commands.hx >> @@ -1264,6 +1264,11 @@ EQMP >> .args_type = "node:B,name:s", >> .mhandler.cmd_new = >> qmp_marshal_input_block_dirty_bitmap_disable, >> }, >> + { >> + .name = "block-dirty-bitmap-clear", >> + .args_type = "node:B,name:s", >> + .mhandler.cmd_new = qmp_marshal_input_block_dirty_bitmap_clear, >> + }, >> SQMP >> @@ -1303,6 +1308,25 @@ Example: >> "name": >> "bitmap0" } } >> <- { "return": {} } >> +block-dirty-bitmap-clear >> +------------------------- > > One dash too many (critical!). > > Max > Yes. >> +Since 2.3 >> + >> +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 >> { > >