From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:57669) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YXc4Y-00009Y-DH for qemu-devel@nongnu.org; Mon, 16 Mar 2015 16:57:15 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1YXc4S-00046T-QY for qemu-devel@nongnu.org; Mon, 16 Mar 2015 16:57:14 -0400 Message-ID: <550743A2.40602@redhat.com> Date: Mon, 16 Mar 2015 16:57:06 -0400 From: Max Reitz MIME-Version: 1.0 References: <1426271419-8277-1-git-send-email-jsnow@redhat.com> <1426271419-8277-12-git-send-email-jsnow@redhat.com> In-Reply-To: <1426271419-8277-12-git-send-email-jsnow@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: John Snow , 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 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 > + 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,