From 94789223da7e51599209395f167a95026e707ab8 Mon Sep 17 00:00:00 2001 From: Kevin Wolf Date: Thu, 5 Dec 2013 12:29:59 +0100 Subject: [PATCH 28/37] block: Make bdrv_pread() a bdrv_prwv_co() wrapper Message-id: <1392117622-28812-29-git-send-email-kwolf@redhat.com> Patchwork-id: 57193 O-Subject: [RHEL-7.0 qemu-kvm PATCH v2 28/37] block: Make bdrv_pread() a bdrv_prwv_co() wrapper Bugzilla: 748906 RH-Acked-by: Laszlo Ersek RH-Acked-by: Stefan Hajnoczi RH-Acked-by: Max Reitz Instead of implementing the alignment adjustment here, use the now existing functionality of bdrv_co_do_preadv(). Signed-off-by: Kevin Wolf Reviewed-by: Max Reitz (cherry picked from commit a3ef65718506fb94cb9e5a903ef9bf9ad8fbe6de) Signed-off-by: Kevin Wolf --- block.c | 49 +++++++++++++------------------------------------ 1 file changed, 13 insertions(+), 36 deletions(-) --- block.c | 51 ++++++++++++++------------------------------------- 1 files changed, 14 insertions(+), 37 deletions(-) diff --git a/block.c b/block.c index 3b5b706..e76dec6 100644 --- a/block.c +++ b/block.c @@ -2566,49 +2566,26 @@ int bdrv_make_zero(BlockDriverState *bs, BdrvRequestFlags flags) } } -int bdrv_pread(BlockDriverState *bs, int64_t offset, - void *buf, int count1) +int bdrv_pread(BlockDriverState *bs, int64_t offset, void *buf, int bytes) { - uint8_t tmp_buf[BDRV_SECTOR_SIZE]; - int len, nb_sectors, count; - int64_t sector_num; + QEMUIOVector qiov; + struct iovec iov = { + .iov_base = (void *)buf, + .iov_len = bytes, + }; int ret; - count = count1; - /* first read to align to sector start */ - len = (BDRV_SECTOR_SIZE - offset) & (BDRV_SECTOR_SIZE - 1); - if (len > count) - len = count; - sector_num = offset >> BDRV_SECTOR_BITS; - if (len > 0) { - if ((ret = bdrv_read(bs, sector_num, tmp_buf, 1)) < 0) - return ret; - memcpy(buf, tmp_buf + (offset & (BDRV_SECTOR_SIZE - 1)), len); - count -= len; - if (count == 0) - return count1; - sector_num++; - buf += len; + if (bytes < 0) { + return -EINVAL; } - /* read the sectors "in place" */ - nb_sectors = count >> BDRV_SECTOR_BITS; - if (nb_sectors > 0) { - if ((ret = bdrv_read(bs, sector_num, buf, nb_sectors)) < 0) - return ret; - sector_num += nb_sectors; - len = nb_sectors << BDRV_SECTOR_BITS; - buf += len; - count -= len; + qemu_iovec_init_external(&qiov, &iov, 1); + ret = bdrv_prwv_co(bs, offset, &qiov, false, 0); + if (ret < 0) { + return ret; } - /* add data from the last sector */ - if (count > 0) { - if ((ret = bdrv_read(bs, sector_num, tmp_buf, 1)) < 0) - return ret; - memcpy(buf, tmp_buf, count); - } - return count1; + return bytes; } int bdrv_pwritev(BlockDriverState *bs, int64_t offset, QEMUIOVector *qiov) -- 1.7.1