From cbad81cef8cc7b220f04600997ea29d7302bae00 Mon Sep 17 00:00:00 2001 From: Eric Blake Date: Tue, 27 Oct 2020 00:05:49 -0500 Subject: nbd: Update qapi to support exporting multiple bitmaps Since 'block-export-add' is new to 5.2, we can still tweak the interface; there, allowing 'bitmaps':['str'] is nicer than 'bitmap':'str'. This wires up the qapi and qemu-nbd changes to permit passing multiple bitmaps as distinct metadata contexts that the NBD client may request, but the actual support for more than one will require a further patch to the server. Note that there are no changes made to the existing deprecated 'nbd-server-add' command; this required splitting the QAPI type BlockExportOptionsNbd, which fortunately does not affect QMP introspection. Signed-off-by: Eric Blake Message-Id: <20201027050556.269064-5-eblake@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy Reviewed-by: Peter Krempa --- nbd/server.c | 19 +++++++++++++------ 1 file changed, 13 insertions(+), 6 deletions(-) (limited to 'nbd/server.c') diff --git a/nbd/server.c b/nbd/server.c index 08b621f70a..8d01662b45 100644 --- a/nbd/server.c +++ b/nbd/server.c @@ -1474,6 +1474,7 @@ static int nbd_export_create(BlockExport *blk_exp, BlockExportOptions *exp_args, uint64_t perm, shared_perm; bool readonly = !exp_args->writable; bool shared = !exp_args->writable; + strList *bitmaps; int ret; assert(exp_args->type == BLOCK_EXPORT_TYPE_NBD); @@ -1533,12 +1534,18 @@ static int nbd_export_create(BlockExport *blk_exp, BlockExportOptions *exp_args, } exp->size = QEMU_ALIGN_DOWN(size, BDRV_SECTOR_SIZE); - if (arg->bitmap) { + /* XXX Allow more than one bitmap */ + if (arg->bitmaps && arg->bitmaps->next) { + error_setg(errp, "multiple bitmaps per export not supported yet"); + return -EOPNOTSUPP; + } + for (bitmaps = arg->bitmaps; bitmaps; bitmaps = bitmaps->next) { + const char *bitmap = bitmaps->value; BlockDriverState *bs = blk_bs(blk); BdrvDirtyBitmap *bm = NULL; while (bs) { - bm = bdrv_find_dirty_bitmap(bs, arg->bitmap); + bm = bdrv_find_dirty_bitmap(bs, bitmap); if (bm != NULL) { break; } @@ -1548,7 +1555,7 @@ static int nbd_export_create(BlockExport *blk_exp, BlockExportOptions *exp_args, if (bm == NULL) { ret = -ENOENT; - error_setg(errp, "Bitmap '%s' is not found", arg->bitmap); + error_setg(errp, "Bitmap '%s' is not found", bitmap); goto fail; } @@ -1562,15 +1569,15 @@ static int nbd_export_create(BlockExport *blk_exp, BlockExportOptions *exp_args, ret = -EINVAL; error_setg(errp, "Enabled bitmap '%s' incompatible with readonly export", - arg->bitmap); + bitmap); goto fail; } bdrv_dirty_bitmap_set_busy(bm, true); exp->export_bitmap = bm; - assert(strlen(arg->bitmap) <= BDRV_BITMAP_MAX_NAME_SIZE); + assert(strlen(bitmap) <= BDRV_BITMAP_MAX_NAME_SIZE); exp->export_bitmap_context = g_strdup_printf("qemu:dirty-bitmap:%s", - arg->bitmap); + bitmap); assert(strlen(exp->export_bitmap_context) < NBD_MAX_STRING_SIZE); } -- cgit v1.2.3