From 734a77584ae13d36113a7a7cd8b54beb49a8a48e Mon Sep 17 00:00:00 2001 From: Kevin Wolf Date: Wed, 1 Jun 2016 17:07:24 +0200 Subject: qcow2: Let vmstate call qcow2_co_preadv/pwrite directly We don't really want to go through the block layer in order to read from or write to the vmstate in a qcow2 image. Doing so required a few ugly hacks like saving and restoring the old image size (because writing to vmstate offsets would increase the image size) or disabling the "reads after EOF = zeroes" logic. When calling the right functions directly, these hacks aren't necessary any more. Note that .bdrv_vmstate_load/save() return 0 instead of the number of bytes in case of success now. Signed-off-by: Kevin Wolf Reviewed-by: Fam Zheng Reviewed-by: Eric Blake Reviewed-by: Stefan Hajnoczi --- block/qcow2.c | 24 ++++-------------------- 1 file changed, 4 insertions(+), 20 deletions(-) (limited to 'block') diff --git a/block/qcow2.c b/block/qcow2.c index 362ada2..4718f82 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -2909,36 +2909,20 @@ static int qcow2_save_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos) { BDRVQcow2State *s = bs->opaque; - int64_t total_sectors = bs->total_sectors; - bool zero_beyond_eof = bs->zero_beyond_eof; - int ret; BLKDBG_EVENT(bs->file, BLKDBG_VMSTATE_SAVE); - bs->zero_beyond_eof = false; - ret = bdrv_pwritev(bs, qcow2_vm_state_offset(s) + pos, qiov); - bs->zero_beyond_eof = zero_beyond_eof; - - /* bdrv_co_do_writev will have increased the total_sectors value to include - * the VM state - the VM state is however not an actual part of the block - * device, therefore, we need to restore the old value. */ - bs->total_sectors = total_sectors; - - return ret; + return bs->drv->bdrv_co_pwritev(bs, qcow2_vm_state_offset(s) + pos, + qiov->size, qiov, 0); } static int qcow2_load_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos) { BDRVQcow2State *s = bs->opaque; - bool zero_beyond_eof = bs->zero_beyond_eof; - int ret; BLKDBG_EVENT(bs->file, BLKDBG_VMSTATE_LOAD); - bs->zero_beyond_eof = false; - ret = bdrv_preadv(bs, qcow2_vm_state_offset(s) + pos, qiov); - bs->zero_beyond_eof = zero_beyond_eof; - - return ret; + return bs->drv->bdrv_co_preadv(bs, qcow2_vm_state_offset(s) + pos, + qiov->size, qiov, 0); } /* -- cgit v1.1