Commit e74e6b78 authored by John Snow's avatar John Snow Committed by Kevin Wolf
Browse files

qmp: add block-dirty-bitmap-clear 



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: default avatarJohn Snow <jsnow@redhat.com>
Reviewed-by: default avatarMax Reitz <mreitz@redhat.com>
Reviewed-by: default avatarStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: default avatarEric Blake <eblake@redhat.com>
Message-id: 1429314609-29776-12-git-send-email-jsnow@redhat.com
Signed-off-by: default avatarStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: default avatarKevin Wolf <kwolf@redhat.com>
parent d58d8453

block.c

+8 −0
Original line number Diff line number Diff line
@@ -63,6 +63,7 @@ 
struct BdrvDirtyBitmap {

    HBitmap *bitmap;

    BdrvDirtyBitmap *successor;

    int64_t size;

    char *name;

    bool disabled;

    QLIST_ENTRY(BdrvDirtyBitmap) list;
@@ -5557,6 +5558,7 @@ BdrvDirtyBitmap *bdrv_create_dirty_bitmap(BlockDriverState *bs, 
    }

    bitmap = g_new0(BdrvDirtyBitmap, 1);

    bitmap->bitmap = hbitmap_alloc(bitmap_size, ctz32(sector_granularity));

    bitmap->size = bitmap_size;

    bitmap->name = g_strdup(name);

    bitmap->disabled = false;

    QLIST_INSERT_HEAD(&bs->dirty_bitmaps, bitmap, list);
@@ -5759,6 +5761,12 @@ 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)

{

blockdev.c

+34 −0
Original line number Diff line number Diff line
@@ -2079,6 +2079,40 @@ 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) {

        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");

include/block/block.h

+1 −0
Original line number Diff line number Diff line
@@ -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);

qapi/block-core.json

+14 −0
Original line number Diff line number Diff line
@@ -1021,6 +1021,20 @@ 
{ 'command': 'block-dirty-bitmap-remove',

  '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:

#

qmp-commands.hx

+29 −0
Original line number Diff line number Diff line
@@ -1361,6 +1361,35 @@ Example: 
                                                      "name": "bitmap0" } }

<- { "return": {} }



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



    {