block: Allow BDRV_REQ_FUA through blk_pwrite()

We have several block drivers that understand BDRV_REQ_FUA,
and emulate it in the block layer for the rest by a full flush.
But without a way to actually request BDRV_REQ_FUA during a
pass-through blk_pwrite(), FUA-aware block drivers like NBD are
forced to repeat the emulation logic of a full flush regardless
of whether the backend they are writing to could do it more
efficiently.

This patch just wires up a flags argument; followup patches
will actually make use of it in the NBD driver and in qemu-io.

Signed-off-by: Eric Blake <eblake@redhat.com>
Acked-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Eric Blake 2016-05-06 10:26:27 -06:00 committed by Kevin Wolf
parent 0e01b76e7c
commit 8341f00dc2
15 changed files with 37 additions and 33 deletions

View file

@ -1808,12 +1808,12 @@ static int vmdk_create_extent(const char *filename, int64_t filesize,
header.check_bytes[3] = 0xa;
/* write all the data */
ret = blk_pwrite(blk, 0, &magic, sizeof(magic));
ret = blk_pwrite(blk, 0, &magic, sizeof(magic), 0);
if (ret < 0) {
error_setg(errp, QERR_IO_ERROR);
goto exit;
}
ret = blk_pwrite(blk, sizeof(magic), &header, sizeof(header));
ret = blk_pwrite(blk, sizeof(magic), &header, sizeof(header), 0);
if (ret < 0) {
error_setg(errp, QERR_IO_ERROR);
goto exit;
@ -1833,7 +1833,7 @@ static int vmdk_create_extent(const char *filename, int64_t filesize,
gd_buf[i] = cpu_to_le32(tmp);
}
ret = blk_pwrite(blk, le64_to_cpu(header.rgd_offset) * BDRV_SECTOR_SIZE,
gd_buf, gd_buf_size);
gd_buf, gd_buf_size, 0);
if (ret < 0) {
error_setg(errp, QERR_IO_ERROR);
goto exit;
@ -1845,7 +1845,7 @@ static int vmdk_create_extent(const char *filename, int64_t filesize,
gd_buf[i] = cpu_to_le32(tmp);
}
ret = blk_pwrite(blk, le64_to_cpu(header.gd_offset) * BDRV_SECTOR_SIZE,
gd_buf, gd_buf_size);
gd_buf, gd_buf_size, 0);
if (ret < 0) {
error_setg(errp, QERR_IO_ERROR);
goto exit;
@ -2120,7 +2120,7 @@ static int vmdk_create(const char *filename, QemuOpts *opts, Error **errp)
blk_set_allow_write_beyond_eof(new_blk, true);
ret = blk_pwrite(new_blk, desc_offset, desc, desc_len);
ret = blk_pwrite(new_blk, desc_offset, desc, desc_len, 0);
if (ret < 0) {
error_setg_errno(errp, -ret, "Could not write description");
goto exit;