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From: Vladimir Sementsov-Ogievskiy To: qemu-block@nongnu.org Subject: [PATCH v2 4/9] block/io: move bdrv_rw_co_entry and friends down Date: Mon, 27 Apr 2020 17:39:02 +0300 Message-Id: <20200427143907.5710-5-vsementsov@virtuozzo.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20200427143907.5710-1-vsementsov@virtuozzo.com> References: <20200427143907.5710-1-vsementsov@virtuozzo.com> Content-Transfer-Encoding: quoted-printable X-ClientProxiedBy: FRYP281CA0010.DEUP281.PROD.OUTLOOK.COM (2603:10a6:d10::20) To AM7PR08MB5494.eurprd08.prod.outlook.com (2603:10a6:20b:dc::15) MIME-Version: 1.0 X-MS-Exchange-MessageSentRepresentingType: 1 X-Mailer: git-send-email 2.21.0 X-Originating-IP: [185.215.60.182] X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id: 3ec3f310-36f2-459f-b11a-08d7eab8cd4c X-MS-TrafficTypeDiagnostic: AM7PR08MB5336: X-MS-Exchange-Transport-Forked: True X-Microsoft-Antispam-PRVS: X-MS-Oob-TLC-OOBClassifiers: OLM:10000; X-Forefront-PRVS: 0386B406AA X-Forefront-Antispam-Report: CIP:255.255.255.255; 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envelope-from=vsementsov@virtuozzo.com; helo=EUR03-DB5-obe.outbound.protection.outlook.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/04/27 10:39:33 X-ACL-Warn: Detected OS = Windows NT kernel [generic] [fuzzy] X-Received-From: 40.107.4.124 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: kwolf@redhat.com, fam@euphon.net, vsementsov@virtuozzo.com, qemu-devel@nongnu.org, mreitz@redhat.com, stefanha@redhat.com, den@openvz.org Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: pass (identity @virtuozzo.com) Content-Type: text/plain; charset="utf-8" We are going to use bdrv_co_pwritev_part and bdrv_co_preadv_part in bdrv_rw_co_entry, so move it down. Note: Comment formatting was changed to conform to coding style and function order was changed. Otherwise the code is unmodified. Signed-off-by: Vladimir Sementsov-Ogievskiy Reviewed-by: Stefan Hajnoczi --- block/io.c | 361 +++++++++++++++++++++++++++-------------------------- 1 file changed, 181 insertions(+), 180 deletions(-) diff --git a/block/io.c b/block/io.c index 1134f8144a..061f3f2590 100644 --- a/block/io.c +++ b/block/io.c @@ -891,186 +891,6 @@ static int bdrv_check_byte_request(BlockDriverState *= bs, int64_t offset, return 0; } =20 -typedef struct RwCo { - BdrvChild *child; - int64_t offset; - QEMUIOVector *qiov; - bool is_write; - int ret; - BdrvRequestFlags flags; -} RwCo; - -static void coroutine_fn bdrv_rw_co_entry(void *opaque) -{ - RwCo *rwco =3D opaque; - - if (!rwco->is_write) { - rwco->ret =3D bdrv_co_preadv(rwco->child, rwco->offset, - rwco->qiov->size, rwco->qiov, - rwco->flags); - } else { - rwco->ret =3D bdrv_co_pwritev(rwco->child, rwco->offset, - rwco->qiov->size, rwco->qiov, - rwco->flags); - } - aio_wait_kick(); -} - -/* - * Process a vectored synchronous request using coroutines - */ -static int bdrv_prwv_co(BdrvChild *child, int64_t offset, - QEMUIOVector *qiov, bool is_write, - BdrvRequestFlags flags) -{ - Coroutine *co; - RwCo rwco =3D { - .child =3D child, - .offset =3D offset, - .qiov =3D qiov, - .is_write =3D is_write, - .ret =3D NOT_DONE, - .flags =3D flags, - }; - - if (qemu_in_coroutine()) { - /* Fast-path if already in coroutine context */ - bdrv_rw_co_entry(&rwco); - } else { - co =3D qemu_coroutine_create(bdrv_rw_co_entry, &rwco); - bdrv_coroutine_enter(child->bs, co); - BDRV_POLL_WHILE(child->bs, rwco.ret =3D=3D NOT_DONE); - } - return rwco.ret; -} - -int bdrv_pwrite_zeroes(BdrvChild *child, int64_t offset, - int bytes, BdrvRequestFlags flags) -{ - QEMUIOVector qiov =3D QEMU_IOVEC_INIT_BUF(qiov, NULL, bytes); - - return bdrv_prwv_co(child, offset, &qiov, true, - BDRV_REQ_ZERO_WRITE | flags); -} - -/* - * Completely zero out a block device with the help of bdrv_pwrite_zeroes. - * The operation is sped up by checking the block status and only writing - * zeroes to the device if they currently do not return zeroes. Optional - * flags are passed through to bdrv_pwrite_zeroes (e.g. BDRV_REQ_MAY_UNMAP, - * BDRV_REQ_FUA). - * - * Returns < 0 on error, 0 on success. For error codes see bdrv_write(). - */ -int bdrv_make_zero(BdrvChild *child, BdrvRequestFlags flags) -{ - int ret; - int64_t target_size, bytes, offset =3D 0; - BlockDriverState *bs =3D child->bs; - - target_size =3D bdrv_getlength(bs); - if (target_size < 0) { - return target_size; - } - - for (;;) { - bytes =3D MIN(target_size - offset, BDRV_REQUEST_MAX_BYTES); - if (bytes <=3D 0) { - return 0; - } - ret =3D bdrv_block_status(bs, offset, bytes, &bytes, NULL, NULL); - if (ret < 0) { - return ret; - } - if (ret & BDRV_BLOCK_ZERO) { - offset +=3D bytes; - continue; - } - ret =3D bdrv_pwrite_zeroes(child, offset, bytes, flags); - if (ret < 0) { - return ret; - } - offset +=3D bytes; - } -} - -int bdrv_preadv(BdrvChild *child, int64_t offset, QEMUIOVector *qiov) -{ - int ret; - - ret =3D bdrv_prwv_co(child, offset, qiov, false, 0); - if (ret < 0) { - return ret; - } - - return qiov->size; -} - -/* See bdrv_pwrite() for the return codes */ -int bdrv_pread(BdrvChild *child, int64_t offset, void *buf, int bytes) -{ - QEMUIOVector qiov =3D QEMU_IOVEC_INIT_BUF(qiov, buf, bytes); - - if (bytes < 0) { - return -EINVAL; - } - - return bdrv_preadv(child, offset, &qiov); -} - -int bdrv_pwritev(BdrvChild *child, int64_t offset, QEMUIOVector *qiov) -{ - int ret; - - ret =3D bdrv_prwv_co(child, offset, qiov, true, 0); - if (ret < 0) { - return ret; - } - - return qiov->size; -} - -/* Return no. of bytes on success or < 0 on error. Important errors are: - -EIO generic I/O error (may happen for all errors) - -ENOMEDIUM No media inserted. - -EINVAL Invalid offset or number of bytes - -EACCES Trying to write a read-only device -*/ -int bdrv_pwrite(BdrvChild *child, int64_t offset, const void *buf, int byt= es) -{ - QEMUIOVector qiov =3D QEMU_IOVEC_INIT_BUF(qiov, buf, bytes); - - if (bytes < 0) { - return -EINVAL; - } - - return bdrv_pwritev(child, offset, &qiov); -} - -/* - * Writes to the file and ensures that no writes are reordered across this - * request (acts as a barrier) - * - * Returns 0 on success, -errno in error cases. - */ -int bdrv_pwrite_sync(BdrvChild *child, int64_t offset, - const void *buf, int count) -{ - int ret; - - ret =3D bdrv_pwrite(child, offset, buf, count); - if (ret < 0) { - return ret; - } - - ret =3D bdrv_flush(child->bs); - if (ret < 0) { - return ret; - } - - return 0; -} - typedef struct CoroutineIOCompletion { Coroutine *coroutine; int ret; @@ -2185,6 +2005,187 @@ int coroutine_fn bdrv_co_pwrite_zeroes(BdrvChild *c= hild, int64_t offset, BDRV_REQ_ZERO_WRITE | flags); } =20 +typedef struct RwCo { + BdrvChild *child; + int64_t offset; + QEMUIOVector *qiov; + bool is_write; + int ret; + BdrvRequestFlags flags; +} RwCo; + +static void coroutine_fn bdrv_rw_co_entry(void *opaque) +{ + RwCo *rwco =3D opaque; + + if (!rwco->is_write) { + rwco->ret =3D bdrv_co_preadv(rwco->child, rwco->offset, + rwco->qiov->size, rwco->qiov, + rwco->flags); + } else { + rwco->ret =3D bdrv_co_pwritev(rwco->child, rwco->offset, + rwco->qiov->size, rwco->qiov, + rwco->flags); + } + aio_wait_kick(); +} + +/* + * Process a vectored synchronous request using coroutines + */ +static int bdrv_prwv_co(BdrvChild *child, int64_t offset, + QEMUIOVector *qiov, bool is_write, + BdrvRequestFlags flags) +{ + Coroutine *co; + RwCo rwco =3D { + .child =3D child, + .offset =3D offset, + .qiov =3D qiov, + .is_write =3D is_write, + .ret =3D NOT_DONE, + .flags =3D flags, + }; + + if (qemu_in_coroutine()) { + /* Fast-path if already in coroutine context */ + bdrv_rw_co_entry(&rwco); + } else { + co =3D qemu_coroutine_create(bdrv_rw_co_entry, &rwco); + bdrv_coroutine_enter(child->bs, co); + BDRV_POLL_WHILE(child->bs, rwco.ret =3D=3D NOT_DONE); + } + return rwco.ret; +} + +int bdrv_pwrite_zeroes(BdrvChild *child, int64_t offset, + int bytes, BdrvRequestFlags flags) +{ + QEMUIOVector qiov =3D QEMU_IOVEC_INIT_BUF(qiov, NULL, bytes); + + return bdrv_prwv_co(child, offset, &qiov, true, + BDRV_REQ_ZERO_WRITE | flags); +} + +/* See bdrv_pwrite() for the return codes */ +int bdrv_pread(BdrvChild *child, int64_t offset, void *buf, int bytes) +{ + QEMUIOVector qiov =3D QEMU_IOVEC_INIT_BUF(qiov, buf, bytes); + + if (bytes < 0) { + return -EINVAL; + } + + return bdrv_preadv(child, offset, &qiov); +} + +int bdrv_pwritev(BdrvChild *child, int64_t offset, QEMUIOVector *qiov) +{ + int ret; + + ret =3D bdrv_prwv_co(child, offset, qiov, true, 0); + if (ret < 0) { + return ret; + } + + return qiov->size; +} + +/* + * Return no. of bytes on success or < 0 on error. Important errors are: + * -EIO generic I/O error (may happen for all errors) + * -ENOMEDIUM No media inserted. + * -EINVAL Invalid offset or number of bytes + * -EACCES Trying to write a read-only device + */ +int bdrv_pwrite(BdrvChild *child, int64_t offset, const void *buf, int byt= es) +{ + QEMUIOVector qiov =3D QEMU_IOVEC_INIT_BUF(qiov, buf, bytes); + + if (bytes < 0) { + return -EINVAL; + } + + return bdrv_pwritev(child, offset, &qiov); +} + +/* + * Writes to the file and ensures that no writes are reordered across this + * request (acts as a barrier) + * + * Returns 0 on success, -errno in error cases. + */ +int bdrv_pwrite_sync(BdrvChild *child, int64_t offset, + const void *buf, int count) +{ + int ret; + + ret =3D bdrv_pwrite(child, offset, buf, count); + if (ret < 0) { + return ret; + } + + ret =3D bdrv_flush(child->bs); + if (ret < 0) { + return ret; + } + + return 0; +} + +/* + * Completely zero out a block device with the help of bdrv_pwrite_zeroes. + * The operation is sped up by checking the block status and only writing + * zeroes to the device if they currently do not return zeroes. Optional + * flags are passed through to bdrv_pwrite_zeroes (e.g. BDRV_REQ_MAY_UNMAP, + * BDRV_REQ_FUA). + * + * Returns < 0 on error, 0 on success. For error codes see bdrv_write(). + */ +int bdrv_make_zero(BdrvChild *child, BdrvRequestFlags flags) +{ + int ret; + int64_t target_size, bytes, offset =3D 0; + BlockDriverState *bs =3D child->bs; + + target_size =3D bdrv_getlength(bs); + if (target_size < 0) { + return target_size; + } + + for (;;) { + bytes =3D MIN(target_size - offset, BDRV_REQUEST_MAX_BYTES); + if (bytes <=3D 0) { + return 0; + } + ret =3D bdrv_block_status(bs, offset, bytes, &bytes, NULL, NULL); + if (ret < 0) { + return ret; + } + if (ret & BDRV_BLOCK_ZERO) { + offset +=3D bytes; + continue; + } + ret =3D bdrv_pwrite_zeroes(child, offset, bytes, flags); + if (ret < 0) { + return ret; + } + offset +=3D bytes; + } +} + +int bdrv_preadv(BdrvChild *child, int64_t offset, QEMUIOVector *qiov) +{ + int ret; + + ret =3D bdrv_prwv_co(child, offset, qiov, false, 0); + if (ret < 0) { + return ret; + } + + return qiov->size; +} + /* * Flush ALL BDSes regardless of if they are reachable via a BlkBackend or= not. */ --=20 2.21.0