[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Qemu-devel] [PATCH 3/3] Combine bdrv_co_readv and bdrv_co_writev into b
|
From: |
Michael Tokarev |
|
Subject: |
[Qemu-devel] [PATCH 3/3] Combine bdrv_co_readv and bdrv_co_writev into bdrv_co_rw_vector |
|
Date: |
Wed, 29 Feb 2012 03:54:36 +0400 |
In block.c, we combine bdrv_co_do_readv(), bdrv_co_do_writev() and
bdrv_co_do_write_zeroes() into single routine, bdrv_co_do_rw_vector(),
and remove lots of now unneded helper functions.
sheepdog driver already had sd_co_rw_vector() which half-combined
read and write paths.
qcow and qcow2 block drivers now contains multiplexing functions
(rw_vector() -> readv()+writev()), since for these drivers, the
read and write routines actually have very little in common.
Signed-off-by: Michael Tokarev <address@hidden>
---
block.c | 206 ++++++++++++++++++-------------------------------
block.h | 6 ++
block/nbd.c | 95 ++++++-----------------
block/qcow.c | 10 ++-
block/qcow2-cluster.c | 4 +-
block/qcow2.c | 13 +++-
block/raw.c | 15 +---
block/sheepdog.c | 125 +++++++++++++-----------------
block_int.h | 6 +-
9 files changed, 186 insertions(+), 294 deletions(-)
diff --git a/block.c b/block.c
index 25ce28b..7a0eed7 100644
--- a/block.c
+++ b/block.c
@@ -49,21 +49,17 @@
#define NOT_DONE 0x7fffffff /* used while emulated sync operation in progress
*/
typedef enum {
- BDRV_REQ_COPY_ON_READ = 0x1,
- BDRV_REQ_ZERO_WRITE = 0x2,
+ BDRV_REQ_READ = 0x0 /* the same as false */,
+ BDRV_REQ_WRITE = 0x1 /* the same as true */,
+ BDRV_REQ_COPY_ON_READ = 0x2,
+ BDRV_REQ_ZERO_WRITE = 0x4,
} BdrvRequestFlags;
static void bdrv_dev_change_media_cb(BlockDriverState *bs, bool load);
-static int coroutine_fn bdrv_co_readv_em(BlockDriverState *bs,
- int64_t sector_num, int nb_sectors,
- QEMUIOVector *iov);
-static int coroutine_fn bdrv_co_writev_em(BlockDriverState *bs,
- int64_t sector_num, int nb_sectors,
- QEMUIOVector *iov);
-static int coroutine_fn bdrv_co_do_readv(BlockDriverState *bs,
- int64_t sector_num, int nb_sectors, QEMUIOVector *qiov,
- BdrvRequestFlags flags);
-static int coroutine_fn bdrv_co_do_writev(BlockDriverState *bs,
+static int coroutine_fn bdrv_co_io_em(BlockDriverState *bs, int64_t sector_num,
+ int nb_sectors, QEMUIOVector *iov,
+ bool is_write);
+static int coroutine_fn bdrv_co_do_rw_vector(BlockDriverState *bs,
int64_t sector_num, int nb_sectors, QEMUIOVector *qiov,
BdrvRequestFlags flags);
static BlockDriverAIOCB *bdrv_co_aio_rw_vector(BlockDriverState *bs,
@@ -267,9 +263,8 @@ void path_combine(char *dest, int dest_size,
void bdrv_register(BlockDriver *bdrv)
{
/* Block drivers without coroutine functions need emulation */
- if (!bdrv->bdrv_co_readv) {
- bdrv->bdrv_co_readv = bdrv_co_readv_em;
- bdrv->bdrv_co_writev = bdrv_co_writev_em;
+ if (!bdrv->bdrv_co_rw_vector) {
+ bdrv->bdrv_co_rw_vector = bdrv_co_io_em;
/* bdrv_co_readv_em()/brdv_co_writev_em() work in terms of aio, so if
* the block driver lacks aio we need to emulate that too.
@@ -1338,14 +1333,9 @@ typedef struct RwCo {
static void coroutine_fn bdrv_rw_co_entry(void *opaque)
{
RwCo *rwco = opaque;
-
- if (!rwco->is_write) {
- rwco->ret = bdrv_co_do_readv(rwco->bs, rwco->sector_num,
- rwco->nb_sectors, rwco->qiov, 0);
- } else {
- rwco->ret = bdrv_co_do_writev(rwco->bs, rwco->sector_num,
- rwco->nb_sectors, rwco->qiov, 0);
- }
+ rwco->ret = bdrv_co_do_rw_vector(rwco->bs, rwco->sector_num,
+ rwco->nb_sectors, rwco->qiov,
+ rwco->is_write ? BDRV_REQ_WRITE : BDRV_REQ_READ);
}
/*
@@ -1580,8 +1570,8 @@ static int coroutine_fn
bdrv_co_do_copy_on_readv(BlockDriverState *bs,
iov.iov_base = bounce_buffer = qemu_blockalign(bs, iov.iov_len);
qemu_iovec_init_external(&bounce_qiov, &iov, 1);
- ret = drv->bdrv_co_readv(bs, cluster_sector_num, cluster_nb_sectors,
- &bounce_qiov);
+ ret = drv->bdrv_co_rw_vector(bs, cluster_sector_num, cluster_nb_sectors,
+ &bounce_qiov, BDRV_READ);
if (ret < 0) {
goto err;
}
@@ -1591,8 +1581,8 @@ static int coroutine_fn
bdrv_co_do_copy_on_readv(BlockDriverState *bs,
ret = drv->bdrv_co_write_zeroes(bs, cluster_sector_num,
cluster_nb_sectors);
} else {
- ret = drv->bdrv_co_writev(bs, cluster_sector_num, cluster_nb_sectors,
- &bounce_qiov);
+ ret = drv->bdrv_co_rw_vector(bs, cluster_sector_num,
cluster_nb_sectors,
+ &bounce_qiov, BDRV_WRITE);
}
if (ret < 0) {
@@ -1613,29 +1603,36 @@ err:
}
/*
- * Handle a read request in coroutine context
+ * Handle a read or write request in coroutine context
+ * This is internal function which is called with flags being
+ * one of READ,WRITE,COPY_ON_READ,ZERO_WRITE, but not any combination.
+ * For ZERO_WRITE, the data (qiov) is not provided.
*/
-static int coroutine_fn bdrv_co_do_readv(BlockDriverState *bs,
+static int coroutine_fn bdrv_co_do_rw_vector(BlockDriverState *bs,
int64_t sector_num, int nb_sectors, QEMUIOVector *qiov,
BdrvRequestFlags flags)
{
BlockDriver *drv = bs->drv;
BdrvTrackedRequest req;
+ bool is_write = flags & (BDRV_REQ_WRITE|BDRV_REQ_ZERO_WRITE);
int ret;
if (!drv) {
return -ENOMEDIUM;
}
+ if (is_write && bs->read_only) {
+ return -EACCES;
+ }
if (bdrv_check_request(bs, sector_num, nb_sectors)) {
return -EIO;
}
/* throttling disk read I/O */
if (bs->io_limits_enabled) {
- bdrv_io_limits_intercept(bs, false, nb_sectors);
+ bdrv_io_limits_intercept(bs, is_write, nb_sectors);
}
- if (bs->copy_on_read) {
+ if (!is_write && bs->copy_on_read) {
flags |= BDRV_REQ_COPY_ON_READ;
}
if (flags & BDRV_REQ_COPY_ON_READ) {
@@ -1646,7 +1643,7 @@ static int coroutine_fn bdrv_co_do_readv(BlockDriverState
*bs,
wait_for_overlapping_requests(bs, sector_num, nb_sectors);
}
- tracked_request_begin(&req, bs, sector_num, nb_sectors, false);
+ tracked_request_begin(&req, bs, sector_num, nb_sectors, is_write);
if (flags & BDRV_REQ_COPY_ON_READ) {
int pnum;
@@ -1662,7 +1659,39 @@ static int coroutine_fn
bdrv_co_do_readv(BlockDriverState *bs,
}
}
- ret = drv->bdrv_co_readv(bs, sector_num, nb_sectors, qiov);
+ if (flags & BDRV_REQ_ZERO_WRITE) {
+
+ /* First try the efficient write zeroes operation */
+ if (drv->bdrv_co_write_zeroes) {
+ ret = drv->bdrv_co_write_zeroes(bs, sector_num, nb_sectors);
+ } else {
+ /* Fall back to bounce buffer if write zeroes is unsupported */
+ QEMUIOVector qiov;
+ struct iovec iov;
+ /*XXX may do better by allocating small buffer and repeating it
several times */
+ iov.iov_len = nb_sectors * BDRV_SECTOR_SIZE;
+ iov.iov_base = qemu_blockalign(bs, iov.iov_len);
+ memset(iov.iov_base, 0, iov.iov_len);
+ qemu_iovec_init_external(&qiov, &iov, 1);
+
+ ret = drv->bdrv_co_rw_vector(bs, sector_num, nb_sectors, &qiov,
BDRV_WRITE);
+
+ qemu_vfree(iov.iov_base);
+ }
+
+ } else {
+ ret = drv->bdrv_co_rw_vector(bs, sector_num, nb_sectors, qiov,
is_write);
+ }
+
+ if (is_write) {
+ if (bs->dirty_bitmap) {
+ set_dirty_bitmap(bs, sector_num, nb_sectors, 1);
+ }
+
+ if (bs->wr_highest_sector < sector_num + nb_sectors - 1) {
+ bs->wr_highest_sector = sector_num + nb_sectors - 1;
+ }
+ }
out:
tracked_request_end(&req);
@@ -1679,7 +1708,7 @@ int coroutine_fn bdrv_co_readv(BlockDriverState *bs,
int64_t sector_num,
{
trace_bdrv_co_readv(bs, sector_num, nb_sectors);
- return bdrv_co_do_readv(bs, sector_num, nb_sectors, qiov, 0);
+ return bdrv_co_do_rw_vector(bs, sector_num, nb_sectors, qiov,
BDRV_REQ_READ);
}
int coroutine_fn bdrv_co_copy_on_readv(BlockDriverState *bs,
@@ -1687,92 +1716,27 @@ int coroutine_fn bdrv_co_copy_on_readv(BlockDriverState
*bs,
{
trace_bdrv_co_copy_on_readv(bs, sector_num, nb_sectors);
- return bdrv_co_do_readv(bs, sector_num, nb_sectors, qiov,
- BDRV_REQ_COPY_ON_READ);
+ return bdrv_co_do_rw_vector(bs, sector_num, nb_sectors, qiov,
+ BDRV_REQ_COPY_ON_READ);
}
-static int coroutine_fn bdrv_co_do_write_zeroes(BlockDriverState *bs,
- int64_t sector_num, int nb_sectors)
+int coroutine_fn bdrv_co_rw_vector(BlockDriverState *bs, int64_t sector_num,
+ int nb_sectors, QEMUIOVector *qiov, bool
is_write)
{
- BlockDriver *drv = bs->drv;
- QEMUIOVector qiov;
- struct iovec iov;
- int ret;
-
- /* First try the efficient write zeroes operation */
- if (drv->bdrv_co_write_zeroes) {
- return drv->bdrv_co_write_zeroes(bs, sector_num, nb_sectors);
- }
-
- /* Fall back to bounce buffer if write zeroes is unsupported */
- iov.iov_len = nb_sectors * BDRV_SECTOR_SIZE;
- iov.iov_base = qemu_blockalign(bs, iov.iov_len);
- memset(iov.iov_base, 0, iov.iov_len);
- qemu_iovec_init_external(&qiov, &iov, 1);
-
- ret = drv->bdrv_co_writev(bs, sector_num, nb_sectors, &qiov);
-
- qemu_vfree(iov.iov_base);
- return ret;
+ return bdrv_co_do_rw_vector(bs, sector_num, nb_sectors, qiov,
+ is_write ? BDRV_REQ_WRITE : BDRV_REQ_READ);
}
/*
* Handle a write request in coroutine context
*/
-static int coroutine_fn bdrv_co_do_writev(BlockDriverState *bs,
- int64_t sector_num, int nb_sectors, QEMUIOVector *qiov,
- BdrvRequestFlags flags)
-{
- BlockDriver *drv = bs->drv;
- BdrvTrackedRequest req;
- int ret;
-
- if (!bs->drv) {
- return -ENOMEDIUM;
- }
- if (bs->read_only) {
- return -EACCES;
- }
- if (bdrv_check_request(bs, sector_num, nb_sectors)) {
- return -EIO;
- }
-
- /* throttling disk write I/O */
- if (bs->io_limits_enabled) {
- bdrv_io_limits_intercept(bs, true, nb_sectors);
- }
-
- if (bs->copy_on_read_in_flight) {
- wait_for_overlapping_requests(bs, sector_num, nb_sectors);
- }
-
- tracked_request_begin(&req, bs, sector_num, nb_sectors, true);
-
- if (flags & BDRV_REQ_ZERO_WRITE) {
- ret = bdrv_co_do_write_zeroes(bs, sector_num, nb_sectors);
- } else {
- ret = drv->bdrv_co_writev(bs, sector_num, nb_sectors, qiov);
- }
-
- if (bs->dirty_bitmap) {
- set_dirty_bitmap(bs, sector_num, nb_sectors, 1);
- }
-
- if (bs->wr_highest_sector < sector_num + nb_sectors - 1) {
- bs->wr_highest_sector = sector_num + nb_sectors - 1;
- }
-
- tracked_request_end(&req);
-
- return ret;
-}
-
int coroutine_fn bdrv_co_writev(BlockDriverState *bs, int64_t sector_num,
int nb_sectors, QEMUIOVector *qiov)
{
trace_bdrv_co_writev(bs, sector_num, nb_sectors);
- return bdrv_co_do_writev(bs, sector_num, nb_sectors, qiov, 0);
+ return bdrv_co_do_rw_vector(bs, sector_num, nb_sectors, qiov,
+ BDRV_REQ_WRITE);
}
int coroutine_fn bdrv_co_write_zeroes(BlockDriverState *bs,
@@ -1780,8 +1744,8 @@ int coroutine_fn bdrv_co_write_zeroes(BlockDriverState
*bs,
{
trace_bdrv_co_write_zeroes(bs, sector_num, nb_sectors);
- return bdrv_co_do_writev(bs, sector_num, nb_sectors, NULL,
- BDRV_REQ_ZERO_WRITE);
+ return bdrv_co_do_rw_vector(bs, sector_num, nb_sectors, NULL,
+ BDRV_REQ_ZERO_WRITE);
}
/**
@@ -3232,13 +3196,9 @@ static void coroutine_fn bdrv_co_do_rw(void *opaque)
BlockDriverAIOCBCoroutine *acb = opaque;
BlockDriverState *bs = acb->common.bs;
- if (!acb->is_write) {
- acb->req.error = bdrv_co_do_readv(bs, acb->req.sector,
- acb->req.nb_sectors, acb->req.qiov, 0);
- } else {
- acb->req.error = bdrv_co_do_writev(bs, acb->req.sector,
- acb->req.nb_sectors, acb->req.qiov, 0);
- }
+ acb->req.error = bdrv_co_do_rw_vector(bs, acb->req.sector,
+ acb->req.nb_sectors, acb->req.qiov,
+ acb->is_write ? BDRV_REQ_WRITE : BDRV_REQ_READ);
acb->bh = qemu_bh_new(bdrv_co_em_bh, acb);
qemu_bh_schedule(acb->bh);
@@ -3394,20 +3354,6 @@ static int coroutine_fn bdrv_co_io_em(BlockDriverState
*bs, int64_t sector_num,
return co.ret;
}
-static int coroutine_fn bdrv_co_readv_em(BlockDriverState *bs,
- int64_t sector_num, int nb_sectors,
- QEMUIOVector *iov)
-{
- return bdrv_co_io_em(bs, sector_num, nb_sectors, iov, false);
-}
-
-static int coroutine_fn bdrv_co_writev_em(BlockDriverState *bs,
- int64_t sector_num, int nb_sectors,
- QEMUIOVector *iov)
-{
- return bdrv_co_io_em(bs, sector_num, nb_sectors, iov, true);
-}
-
static void coroutine_fn bdrv_flush_co_entry(void *opaque)
{
RwCo *rwco = opaque;
diff --git a/block.h b/block.h
index f0f68e0..f15d3ce 100644
--- a/block.h
+++ b/block.h
@@ -78,6 +78,10 @@ typedef struct BlockDevOps {
#define BDRV_SECTOR_SIZE (1ULL << BDRV_SECTOR_BITS)
#define BDRV_SECTOR_MASK ~(BDRV_SECTOR_SIZE - 1)
+/* defines for is_write for bdrv_*_rw_vector */
+#define BDRV_READ false
+#define BDRV_WRITE true
+
typedef enum {
BLOCK_ERR_REPORT, BLOCK_ERR_IGNORE, BLOCK_ERR_STOP_ENOSPC,
BLOCK_ERR_STOP_ANY
@@ -140,6 +144,8 @@ int bdrv_pwrite(BlockDriverState *bs, int64_t offset,
const void *buf, int count);
int bdrv_pwrite_sync(BlockDriverState *bs, int64_t offset,
const void *buf, int count);
+int coroutine_fn bdrv_co_rw_vector(BlockDriverState *bs, int64_t sector_num,
+ int nb_sectors, QEMUIOVector *qiov, bool
is_write);
int coroutine_fn bdrv_co_readv(BlockDriverState *bs, int64_t sector_num,
int nb_sectors, QEMUIOVector *qiov);
int coroutine_fn bdrv_co_copy_on_readv(BlockDriverState *bs,
diff --git a/block/nbd.c b/block/nbd.c
index 161b299..7b757bb 100644
--- a/block/nbd.c
+++ b/block/nbd.c
@@ -320,91 +320,45 @@ static int nbd_open(BlockDriverState *bs, const char*
filename, int flags)
return result;
}
-static int nbd_co_readv_1(BlockDriverState *bs, int64_t sector_num,
- int nb_sectors, QEMUIOVector *qiov,
- int offset)
-{
- BDRVNBDState *s = bs->opaque;
- struct nbd_request request;
- struct nbd_reply reply;
-
- request.type = NBD_CMD_READ;
- request.from = sector_num * 512;
- request.len = nb_sectors * 512;
-
- nbd_coroutine_start(s, &request);
- if (nbd_co_send_request(s, &request, NULL, 0) == -1) {
- reply.error = errno;
- } else {
- nbd_co_receive_reply(s, &request, &reply, qiov->iov, offset);
- }
- nbd_coroutine_end(s, &request);
- return -reply.error;
-
-}
+/* qemu-nbd has a limit of slightly less than 1M per request. Try to
+ * remain aligned to 4K. */
+#define NBD_MAX_SECTORS 2040
-static int nbd_co_writev_1(BlockDriverState *bs, int64_t sector_num,
- int nb_sectors, QEMUIOVector *qiov,
- int offset)
+static int nbd_co_rw_vector(BlockDriverState *bs, int64_t sector_num,
+ int nb_sectors, QEMUIOVector *qiov, bool is_write)
{
BDRVNBDState *s = bs->opaque;
+ int offset = 0;
struct nbd_request request;
struct nbd_reply reply;
- request.type = NBD_CMD_WRITE;
- if (!bdrv_enable_write_cache(bs) && (s->nbdflags & NBD_FLAG_SEND_FUA)) {
+ request.type = is_write ? NBD_CMD_WRITE : NBD_CMD_READ;
+ if (is_write && !bdrv_enable_write_cache(bs) && (s->nbdflags &
NBD_FLAG_SEND_FUA)) {
request.type |= NBD_CMD_FLAG_FUA;
}
+ reply.error = 0;
- request.from = sector_num * 512;
- request.len = nb_sectors * 512;
+ do {
- nbd_coroutine_start(s, &request);
- if (nbd_co_send_request(s, &request, qiov->iov, offset) == -1) {
- reply.error = errno;
- } else {
- nbd_co_receive_reply(s, &request, &reply, NULL, 0);
- }
- nbd_coroutine_end(s, &request);
- return -reply.error;
-}
+ request.from = sector_num * 512;
+ request.len = MIN(nb_sectors, NBD_MAX_SECTORS) * 512;
-/* qemu-nbd has a limit of slightly less than 1M per request. Try to
- * remain aligned to 4K. */
-#define NBD_MAX_SECTORS 2040
+ nbd_coroutine_start(s, &request);
+ /* send_request() and receive_reply() ignores offset if iov is NULL */
+ if (nbd_co_send_request(s, &request, is_write ? qiov->iov : NULL,
offset) == -1) {
+ reply.error = errno;
+ } else {
+ nbd_co_receive_reply(s, &request, &reply, is_write ? NULL :
qiov->iov, offset);
+ }
+ nbd_coroutine_end(s, &request);
-static int nbd_co_readv(BlockDriverState *bs, int64_t sector_num,
- int nb_sectors, QEMUIOVector *qiov)
-{
- int offset = 0;
- int ret;
- while (nb_sectors > NBD_MAX_SECTORS) {
- ret = nbd_co_readv_1(bs, sector_num, NBD_MAX_SECTORS, qiov, offset);
- if (ret < 0) {
- return ret;
- }
offset += NBD_MAX_SECTORS * 512;
sector_num += NBD_MAX_SECTORS;
nb_sectors -= NBD_MAX_SECTORS;
- }
- return nbd_co_readv_1(bs, sector_num, nb_sectors, qiov, offset);
-}
-static int nbd_co_writev(BlockDriverState *bs, int64_t sector_num,
- int nb_sectors, QEMUIOVector *qiov)
-{
- int offset = 0;
- int ret;
- while (nb_sectors > NBD_MAX_SECTORS) {
- ret = nbd_co_writev_1(bs, sector_num, NBD_MAX_SECTORS, qiov, offset);
- if (ret < 0) {
- return ret;
- }
- offset += NBD_MAX_SECTORS * 512;
- sector_num += NBD_MAX_SECTORS;
- nb_sectors -= NBD_MAX_SECTORS;
- }
- return nbd_co_writev_1(bs, sector_num, nb_sectors, qiov, offset);
+ } while (reply.error == 0 && nb_sectors > 0);
+
+ return -reply.error;
}
static int nbd_co_flush(BlockDriverState *bs)
@@ -479,8 +433,7 @@ static BlockDriver bdrv_nbd = {
.format_name = "nbd",
.instance_size = sizeof(BDRVNBDState),
.bdrv_file_open = nbd_open,
- .bdrv_co_readv = nbd_co_readv,
- .bdrv_co_writev = nbd_co_writev,
+ .bdrv_co_rw_vector = nbd_co_rw_vector,
.bdrv_close = nbd_close,
.bdrv_co_flush_to_os = nbd_co_flush,
.bdrv_co_discard = nbd_co_discard,
diff --git a/block/qcow.c b/block/qcow.c
index b1cfe1f..1c4191a 100644
--- a/block/qcow.c
+++ b/block/qcow.c
@@ -629,6 +629,13 @@ static coroutine_fn int qcow_co_writev(BlockDriverState
*bs, int64_t sector_num,
return ret;
}
+static coroutine_fn int qcow_co_rw_vector(BlockDriverState *bs, int64_t
sector_num,
+ int nb_sectors, QEMUIOVector *qiov, bool is_write)
+{
+ return is_write ? qcow_co_writev(bs, sector_num, nb_sectors, qiov)
+ : qcow_co_readv(bs, sector_num, nb_sectors, qiov);
+}
+
static void qcow_close(BlockDriverState *bs)
{
BDRVQcowState *s = bs->opaque;
@@ -875,8 +882,7 @@ static BlockDriver bdrv_qcow = {
.bdrv_close = qcow_close,
.bdrv_create = qcow_create,
- .bdrv_co_readv = qcow_co_readv,
- .bdrv_co_writev = qcow_co_writev,
+ .bdrv_co_rw_vector = qcow_co_rw_vector,
.bdrv_co_flush_to_disk = qcow_co_flush,
.bdrv_co_is_allocated = qcow_co_is_allocated,
diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c
index 07a2e93..b5011e0 100644
--- a/block/qcow2-cluster.c
+++ b/block/qcow2-cluster.c
@@ -320,11 +320,11 @@ static int coroutine_fn copy_sectors(BlockDriverState *bs,
BLKDBG_EVENT(bs->file, BLKDBG_COW_READ);
- /* Call .bdrv_co_readv() directly instead of using the public block-layer
+ /* Call .bdrv_co_rw_vector() directly instead of using the public
block-layer
* interface. This avoids double I/O throttling and request tracking,
* which can lead to deadlock when block layer copy-on-read is enabled.
*/
- ret = bs->drv->bdrv_co_readv(bs, start_sect + n_start, n, &qiov);
+ ret = bs->drv->bdrv_co_rw_vector(bs, start_sect + n_start, n, &qiov,
false);
if (ret < 0) {
goto out;
}
diff --git a/block/qcow2.c b/block/qcow2.c
index 3692b45..517c443 100644
--- a/block/qcow2.c
+++ b/block/qcow2.c
@@ -648,6 +648,16 @@ fail:
return ret;
}
+static coroutine_fn int qcow2_co_rw_vector(BlockDriverState *bs,
+ int64_t sector_num,
+ int nb_sectors,
+ QEMUIOVector *qiov, bool is_write)
+{
+ return is_write ? qcow2_co_writev(bs, sector_num, nb_sectors, qiov)
+ : qcow2_co_readv(bs, sector_num, nb_sectors, qiov);
+}
+
+
static void qcow2_close(BlockDriverState *bs)
{
BDRVQcowState *s = bs->opaque;
@@ -1359,8 +1369,7 @@ static BlockDriver bdrv_qcow2 = {
.bdrv_set_key = qcow2_set_key,
.bdrv_make_empty = qcow2_make_empty,
- .bdrv_co_readv = qcow2_co_readv,
- .bdrv_co_writev = qcow2_co_writev,
+ .bdrv_co_rw_vector = qcow2_co_rw_vector,
.bdrv_co_flush_to_os = qcow2_co_flush_to_os,
.bdrv_co_flush_to_disk = qcow2_co_flush_to_disk,
diff --git a/block/raw.c b/block/raw.c
index 1cdac0c..5348553 100644
--- a/block/raw.c
+++ b/block/raw.c
@@ -9,16 +9,10 @@ static int raw_open(BlockDriverState *bs, int flags)
return 0;
}
-static int coroutine_fn raw_co_readv(BlockDriverState *bs, int64_t sector_num,
- int nb_sectors, QEMUIOVector *qiov)
+static int coroutine_fn raw_co_rw_vector(BlockDriverState *bs, int64_t
sector_num,
+ int nb_sectors, QEMUIOVector *qiov,
bool is_write)
{
- return bdrv_co_readv(bs->file, sector_num, nb_sectors, qiov);
-}
-
-static int coroutine_fn raw_co_writev(BlockDriverState *bs, int64_t sector_num,
- int nb_sectors, QEMUIOVector *qiov)
-{
- return bdrv_co_writev(bs->file, sector_num, nb_sectors, qiov);
+ return bdrv_co_rw_vector(bs->file, sector_num, nb_sectors, qiov, is_write);
}
static void raw_close(BlockDriverState *bs)
@@ -111,8 +105,7 @@ static BlockDriver bdrv_raw = {
.bdrv_open = raw_open,
.bdrv_close = raw_close,
- .bdrv_co_readv = raw_co_readv,
- .bdrv_co_writev = raw_co_writev,
+ .bdrv_co_rw_vector = raw_co_rw_vector,
.bdrv_co_flush_to_disk = raw_co_flush,
.bdrv_co_discard = raw_co_discard,
diff --git a/block/sheepdog.c b/block/sheepdog.c
index 00276f6f..d768dbf 100644
--- a/block/sheepdog.c
+++ b/block/sheepdog.c
@@ -1419,28 +1419,60 @@ out:
* Returns 1 when we need to wait a response, 0 when there is no sent
* request and -errno in error cases.
*/
-static int coroutine_fn sd_co_rw_vector(void *p)
+static coroutine_fn int sd_co_rw_vector(BlockDriverState *bs, int64_t
sector_num,
+ int nb_sectors, QEMUIOVector *qiov,
bool is_write)
{
- SheepdogAIOCB *acb = p;
+ SheepdogAIOCB *acb;
int ret = 0;
- unsigned long len, done = 0, total = acb->nb_sectors * SECTOR_SIZE;
- unsigned long idx = acb->sector_num * SECTOR_SIZE / SD_DATA_OBJ_SIZE;
+ unsigned long len, done = 0, total = nb_sectors * SECTOR_SIZE;
+ unsigned long idx = sector_num * SECTOR_SIZE / SD_DATA_OBJ_SIZE;
uint64_t oid;
- uint64_t offset = (acb->sector_num * SECTOR_SIZE) % SD_DATA_OBJ_SIZE;
- BDRVSheepdogState *s = acb->common.bs->opaque;
+ uint64_t offset = (sector_num * SECTOR_SIZE) % SD_DATA_OBJ_SIZE;
+ BDRVSheepdogState *s = bs->opaque;
SheepdogInode *inode = &s->inode;
AIOReq *aio_req;
- if (acb->aiocb_type == AIOCB_WRITE_UDATA && s->is_snapshot) {
+ if (is_write && bs->growable && sector_num + nb_sectors >
bs->total_sectors) {
+ /* TODO: shouldn't block here */
+ if (sd_truncate(bs, (sector_num + nb_sectors) * SECTOR_SIZE) < 0) {
+ return -EIO;
+ }
+ bs->total_sectors = sector_num + nb_sectors;
+ }
+
+ acb = sd_aio_setup(bs, qiov, sector_num, nb_sectors, NULL, NULL);
+
+ if (is_write) {
+
+ acb->aio_done_func = sd_write_done;
+ acb->aiocb_type = AIOCB_WRITE_UDATA;
+
+ if (s->is_snapshot) {
+ /*
+ * In the case we open the snapshot VDI, Sheepdog creates the
+ * writable VDI when we do a write operation first.
+ */
+ ret = sd_create_branch(s);
+ if (ret) {
+ acb->ret = -EIO;
+ goto out;
+ }
+ }
+
+ } else { /* read */
+
+ int i;
+ acb->aiocb_type = AIOCB_READ_UDATA;
+ acb->aio_done_func = sd_finish_aiocb;
+
/*
- * In the case we open the snapshot VDI, Sheepdog creates the
- * writable VDI when we do a write operation first.
+ * TODO: we can do better; we don't need to initialize
+ * blindly.
*/
- ret = sd_create_branch(s);
- if (ret) {
- acb->ret = -EIO;
- goto out;
+ for (i = 0; i < qiov->niov; i++) {
+ memset(qiov->iov[i].iov_base, 0, qiov->iov[i].iov_len);
}
+
}
while (done != total) {
@@ -1453,12 +1485,12 @@ static int coroutine_fn sd_co_rw_vector(void *p)
len = MIN(total - done, SD_DATA_OBJ_SIZE - offset);
if (!inode->data_vdi_id[idx]) {
- if (acb->aiocb_type == AIOCB_READ_UDATA) {
+ if (!is_write) {
goto done;
}
create = 1;
- } else if (acb->aiocb_type == AIOCB_WRITE_UDATA
+ } else if (is_write
&& !is_data_obj_writable(inode, idx)) {
/* Copy-On-Write */
create = 1;
@@ -1511,63 +1543,13 @@ static int coroutine_fn sd_co_rw_vector(void *p)
done += len;
}
out:
- if (QLIST_EMPTY(&acb->aioreq_head)) {
- return acb->ret;
- }
- return 1;
-}
-
-static coroutine_fn int sd_co_writev(BlockDriverState *bs, int64_t sector_num,
- int nb_sectors, QEMUIOVector *qiov)
-{
- SheepdogAIOCB *acb;
- int ret;
- if (bs->growable && sector_num + nb_sectors > bs->total_sectors) {
- /* TODO: shouldn't block here */
- if (sd_truncate(bs, (sector_num + nb_sectors) * SECTOR_SIZE) < 0) {
- return -EIO;
- }
- bs->total_sectors = sector_num + nb_sectors;
- }
-
- acb = sd_aio_setup(bs, qiov, sector_num, nb_sectors, NULL, NULL);
- acb->aio_done_func = sd_write_done;
- acb->aiocb_type = AIOCB_WRITE_UDATA;
-
- ret = sd_co_rw_vector(acb);
- if (ret <= 0) {
- qemu_aio_release(acb);
- return ret;
- }
-
- qemu_coroutine_yield();
- return acb->ret;
-}
-
-static coroutine_fn int sd_co_readv(BlockDriverState *bs, int64_t sector_num,
- int nb_sectors, QEMUIOVector *qiov)
-{
- SheepdogAIOCB *acb;
- int i, ret;
-
- acb = sd_aio_setup(bs, qiov, sector_num, nb_sectors, NULL, NULL);
- acb->aiocb_type = AIOCB_READ_UDATA;
- acb->aio_done_func = sd_finish_aiocb;
-
- /*
- * TODO: we can do better; we don't need to initialize
- * blindly.
- */
- for (i = 0; i < qiov->niov; i++) {
- memset(qiov->iov[i].iov_base, 0, qiov->iov[i].iov_len);
- }
-
- ret = sd_co_rw_vector(acb);
- if (ret <= 0) {
- qemu_aio_release(acb);
- return ret;
+ if (QLIST_EMPTY(&acb->aioreq_head)) {
+ if (acb->ret <= 0) {
+ qemu_aio_release(acb);
+ return acb->ret;
+ }
}
qemu_coroutine_yield();
@@ -1902,8 +1884,7 @@ BlockDriver bdrv_sheepdog = {
.bdrv_getlength = sd_getlength,
.bdrv_truncate = sd_truncate,
- .bdrv_co_readv = sd_co_readv,
- .bdrv_co_writev = sd_co_writev,
+ .bdrv_co_rw_vector = sd_co_rw_vector,
.bdrv_snapshot_create = sd_snapshot_create,
.bdrv_snapshot_goto = sd_snapshot_goto,
diff --git a/block_int.h b/block_int.h
index aeafa2e..146d9b7 100644
--- a/block_int.h
+++ b/block_int.h
@@ -122,10 +122,8 @@ struct BlockDriver {
int64_t sector_num, int nb_sectors,
BlockDriverCompletionFunc *cb, void *opaque);
- int coroutine_fn (*bdrv_co_readv)(BlockDriverState *bs,
- int64_t sector_num, int nb_sectors, QEMUIOVector *qiov);
- int coroutine_fn (*bdrv_co_writev)(BlockDriverState *bs,
- int64_t sector_num, int nb_sectors, QEMUIOVector *qiov);
+ int coroutine_fn (*bdrv_co_rw_vector)(BlockDriverState *bs,
+ int64_t sector_num, int nb_sectors, QEMUIOVector *qiov, bool is_write);
/*
* Efficiently zero a region of the disk image. Typically an image format
* would use a compact metadata representation to implement this. This
--
1.7.9
- [Qemu-devel] [PATCH 3/3] Combine bdrv_co_readv and bdrv_co_writev into bdrv_co_rw_vector,
Michael Tokarev <=