diff options
Diffstat (limited to 'block/io.c')
| -rw-r--r-- | block/io.c | 240 |
1 files changed, 37 insertions, 203 deletions
diff --git a/block/io.c b/block/io.c index 91611ffb2a..9bba730a7e 100644 --- a/block/io.c +++ b/block/io.c @@ -34,16 +34,8 @@ #define NOT_DONE 0x7fffffff /* used while emulated sync operation in progress */ -static BlockAIOCB *bdrv_co_aio_prw_vector(BdrvChild *child, - int64_t offset, - QEMUIOVector *qiov, - BdrvRequestFlags flags, - BlockCompletionFunc *cb, - void *opaque, - bool is_write); -static void coroutine_fn bdrv_co_do_rw(void *opaque); static int coroutine_fn bdrv_co_do_pwrite_zeroes(BlockDriverState *bs, - int64_t offset, int count, BdrvRequestFlags flags); + int64_t offset, int bytes, BdrvRequestFlags flags); void bdrv_parent_drained_begin(BlockDriverState *bs) { @@ -674,12 +666,12 @@ int bdrv_write(BdrvChild *child, int64_t sector_num, } int bdrv_pwrite_zeroes(BdrvChild *child, int64_t offset, - int count, BdrvRequestFlags flags) + int bytes, BdrvRequestFlags flags) { QEMUIOVector qiov; struct iovec iov = { .iov_base = NULL, - .iov_len = count, + .iov_len = bytes, }; qemu_iovec_init_external(&qiov, &iov, 1); @@ -1220,7 +1212,7 @@ int coroutine_fn bdrv_co_readv(BdrvChild *child, int64_t sector_num, #define MAX_WRITE_ZEROES_BOUNCE_BUFFER (32768 << BDRV_SECTOR_BITS) static int coroutine_fn bdrv_co_do_pwrite_zeroes(BlockDriverState *bs, - int64_t offset, int count, BdrvRequestFlags flags) + int64_t offset, int bytes, BdrvRequestFlags flags) { BlockDriver *drv = bs->drv; QEMUIOVector qiov; @@ -1238,12 +1230,12 @@ static int coroutine_fn bdrv_co_do_pwrite_zeroes(BlockDriverState *bs, assert(alignment % bs->bl.request_alignment == 0); head = offset % alignment; - tail = (offset + count) % alignment; + tail = (offset + bytes) % alignment; max_write_zeroes = QEMU_ALIGN_DOWN(max_write_zeroes, alignment); assert(max_write_zeroes >= bs->bl.request_alignment); - while (count > 0 && !ret) { - int num = count; + while (bytes > 0 && !ret) { + int num = bytes; /* Align request. Block drivers can expect the "bulk" of the request * to be aligned, and that unaligned requests do not cross cluster @@ -1253,7 +1245,7 @@ static int coroutine_fn bdrv_co_do_pwrite_zeroes(BlockDriverState *bs, /* Make a small request up to the first aligned sector. For * convenience, limit this request to max_transfer even if * we don't need to fall back to writes. */ - num = MIN(MIN(count, max_transfer), alignment - head); + num = MIN(MIN(bytes, max_transfer), alignment - head); head = (head + num) % alignment; assert(num < max_write_zeroes); } else if (tail && num > alignment) { @@ -1314,7 +1306,7 @@ static int coroutine_fn bdrv_co_do_pwrite_zeroes(BlockDriverState *bs, } offset += num; - count -= num; + bytes -= num; } fail: @@ -1666,15 +1658,15 @@ int coroutine_fn bdrv_co_writev(BdrvChild *child, int64_t sector_num, } int coroutine_fn bdrv_co_pwrite_zeroes(BdrvChild *child, int64_t offset, - int count, BdrvRequestFlags flags) + int bytes, BdrvRequestFlags flags) { - trace_bdrv_co_pwrite_zeroes(child->bs, offset, count, flags); + trace_bdrv_co_pwrite_zeroes(child->bs, offset, bytes, flags); if (!(child->bs->open_flags & BDRV_O_UNMAP)) { flags &= ~BDRV_REQ_MAY_UNMAP; } - return bdrv_co_pwritev(child, offset, count, NULL, + return bdrv_co_pwritev(child, offset, bytes, NULL, BDRV_REQ_ZERO_WRITE | flags); } @@ -1980,17 +1972,24 @@ bdrv_co_rw_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos, bool is_read) { BlockDriver *drv = bs->drv; + int ret = -ENOTSUP; + + bdrv_inc_in_flight(bs); if (!drv) { - return -ENOMEDIUM; + ret = -ENOMEDIUM; } else if (drv->bdrv_load_vmstate) { - return is_read ? drv->bdrv_load_vmstate(bs, qiov, pos) - : drv->bdrv_save_vmstate(bs, qiov, pos); + if (is_read) { + ret = drv->bdrv_load_vmstate(bs, qiov, pos); + } else { + ret = drv->bdrv_save_vmstate(bs, qiov, pos); + } } else if (bs->file) { - return bdrv_co_rw_vmstate(bs->file->bs, qiov, pos, is_read); + ret = bdrv_co_rw_vmstate(bs->file->bs, qiov, pos, is_read); } - return -ENOTSUP; + bdrv_dec_in_flight(bs); + return ret; } static void coroutine_fn bdrv_co_rw_vmstate_entry(void *opaque) @@ -2016,9 +2015,7 @@ bdrv_rw_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos, Coroutine *co = qemu_coroutine_create(bdrv_co_rw_vmstate_entry, &data); bdrv_coroutine_enter(bs, co); - while (data.ret == -EINPROGRESS) { - aio_poll(bdrv_get_aio_context(bs), true); - } + BDRV_POLL_WHILE(bs, data.ret == -EINPROGRESS); return data.ret; } } @@ -2075,28 +2072,6 @@ int bdrv_readv_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos) /**************************************************************/ /* async I/Os */ -BlockAIOCB *bdrv_aio_readv(BdrvChild *child, int64_t sector_num, - QEMUIOVector *qiov, int nb_sectors, - BlockCompletionFunc *cb, void *opaque) -{ - trace_bdrv_aio_readv(child->bs, sector_num, nb_sectors, opaque); - - assert(nb_sectors << BDRV_SECTOR_BITS == qiov->size); - return bdrv_co_aio_prw_vector(child, sector_num << BDRV_SECTOR_BITS, qiov, - 0, cb, opaque, false); -} - -BlockAIOCB *bdrv_aio_writev(BdrvChild *child, int64_t sector_num, - QEMUIOVector *qiov, int nb_sectors, - BlockCompletionFunc *cb, void *opaque) -{ - trace_bdrv_aio_writev(child->bs, sector_num, nb_sectors, opaque); - - assert(nb_sectors << BDRV_SECTOR_BITS == qiov->size); - return bdrv_co_aio_prw_vector(child, sector_num << BDRV_SECTOR_BITS, qiov, - 0, cb, opaque, true); -} - void bdrv_aio_cancel(BlockAIOCB *acb) { qemu_aio_ref(acb); @@ -2129,147 +2104,6 @@ void bdrv_aio_cancel_async(BlockAIOCB *acb) } /**************************************************************/ -/* async block device emulation */ - -typedef struct BlockRequest { - union { - /* Used during read, write, trim */ - struct { - int64_t offset; - int bytes; - int flags; - QEMUIOVector *qiov; - }; - /* Used during ioctl */ - struct { - int req; - void *buf; - }; - }; - BlockCompletionFunc *cb; - void *opaque; - - int error; -} BlockRequest; - -typedef struct BlockAIOCBCoroutine { - BlockAIOCB common; - BdrvChild *child; - BlockRequest req; - bool is_write; - bool need_bh; - bool *done; -} BlockAIOCBCoroutine; - -static const AIOCBInfo bdrv_em_co_aiocb_info = { - .aiocb_size = sizeof(BlockAIOCBCoroutine), -}; - -static void bdrv_co_complete(BlockAIOCBCoroutine *acb) -{ - if (!acb->need_bh) { - bdrv_dec_in_flight(acb->common.bs); - acb->common.cb(acb->common.opaque, acb->req.error); - qemu_aio_unref(acb); - } -} - -static void bdrv_co_em_bh(void *opaque) -{ - BlockAIOCBCoroutine *acb = opaque; - - assert(!acb->need_bh); - bdrv_co_complete(acb); -} - -static void bdrv_co_maybe_schedule_bh(BlockAIOCBCoroutine *acb) -{ - acb->need_bh = false; - if (acb->req.error != -EINPROGRESS) { - BlockDriverState *bs = acb->common.bs; - - aio_bh_schedule_oneshot(bdrv_get_aio_context(bs), bdrv_co_em_bh, acb); - } -} - -/* Invoke bdrv_co_do_readv/bdrv_co_do_writev */ -static void coroutine_fn bdrv_co_do_rw(void *opaque) -{ - BlockAIOCBCoroutine *acb = opaque; - - if (!acb->is_write) { - acb->req.error = bdrv_co_preadv(acb->child, acb->req.offset, - acb->req.qiov->size, acb->req.qiov, acb->req.flags); - } else { - acb->req.error = bdrv_co_pwritev(acb->child, acb->req.offset, - acb->req.qiov->size, acb->req.qiov, acb->req.flags); - } - - bdrv_co_complete(acb); -} - -static BlockAIOCB *bdrv_co_aio_prw_vector(BdrvChild *child, - int64_t offset, - QEMUIOVector *qiov, - BdrvRequestFlags flags, - BlockCompletionFunc *cb, - void *opaque, - bool is_write) -{ - Coroutine *co; - BlockAIOCBCoroutine *acb; - - /* Matched by bdrv_co_complete's bdrv_dec_in_flight. */ - bdrv_inc_in_flight(child->bs); - - acb = qemu_aio_get(&bdrv_em_co_aiocb_info, child->bs, cb, opaque); - acb->child = child; - acb->need_bh = true; - acb->req.error = -EINPROGRESS; - acb->req.offset = offset; - acb->req.qiov = qiov; - acb->req.flags = flags; - acb->is_write = is_write; - - co = qemu_coroutine_create(bdrv_co_do_rw, acb); - bdrv_coroutine_enter(child->bs, co); - - bdrv_co_maybe_schedule_bh(acb); - return &acb->common; -} - -static void coroutine_fn bdrv_aio_flush_co_entry(void *opaque) -{ - BlockAIOCBCoroutine *acb = opaque; - BlockDriverState *bs = acb->common.bs; - - acb->req.error = bdrv_co_flush(bs); - bdrv_co_complete(acb); -} - -BlockAIOCB *bdrv_aio_flush(BlockDriverState *bs, - BlockCompletionFunc *cb, void *opaque) -{ - trace_bdrv_aio_flush(bs, opaque); - - Coroutine *co; - BlockAIOCBCoroutine *acb; - - /* Matched by bdrv_co_complete's bdrv_dec_in_flight. */ - bdrv_inc_in_flight(bs); - - acb = qemu_aio_get(&bdrv_em_co_aiocb_info, bs, cb, opaque); - acb->need_bh = true; - acb->req.error = -EINPROGRESS; - - co = qemu_coroutine_create(bdrv_aio_flush_co_entry, acb); - bdrv_coroutine_enter(bs, co); - - bdrv_co_maybe_schedule_bh(acb); - return &acb->common; -} - -/**************************************************************/ /* Coroutine block device emulation */ typedef struct FlushCo { @@ -2414,18 +2248,18 @@ int bdrv_flush(BlockDriverState *bs) typedef struct DiscardCo { BlockDriverState *bs; int64_t offset; - int count; + int bytes; int ret; } DiscardCo; static void coroutine_fn bdrv_pdiscard_co_entry(void *opaque) { DiscardCo *rwco = opaque; - rwco->ret = bdrv_co_pdiscard(rwco->bs, rwco->offset, rwco->count); + rwco->ret = bdrv_co_pdiscard(rwco->bs, rwco->offset, rwco->bytes); } int coroutine_fn bdrv_co_pdiscard(BlockDriverState *bs, int64_t offset, - int count) + int bytes) { BdrvTrackedRequest req; int max_pdiscard, ret; @@ -2435,7 +2269,7 @@ int coroutine_fn bdrv_co_pdiscard(BlockDriverState *bs, int64_t offset, return -ENOMEDIUM; } - ret = bdrv_check_byte_request(bs, offset, count); + ret = bdrv_check_byte_request(bs, offset, bytes); if (ret < 0) { return ret; } else if (bs->read_only) { @@ -2460,10 +2294,10 @@ int coroutine_fn bdrv_co_pdiscard(BlockDriverState *bs, int64_t offset, align = MAX(bs->bl.pdiscard_alignment, bs->bl.request_alignment); assert(align % bs->bl.request_alignment == 0); head = offset % align; - tail = (offset + count) % align; + tail = (offset + bytes) % align; bdrv_inc_in_flight(bs); - tracked_request_begin(&req, bs, offset, count, BDRV_TRACKED_DISCARD); + tracked_request_begin(&req, bs, offset, bytes, BDRV_TRACKED_DISCARD); ret = notifier_with_return_list_notify(&bs->before_write_notifiers, &req); if (ret < 0) { @@ -2474,13 +2308,13 @@ int coroutine_fn bdrv_co_pdiscard(BlockDriverState *bs, int64_t offset, align); assert(max_pdiscard >= bs->bl.request_alignment); - while (count > 0) { + while (bytes > 0) { int ret; - int num = count; + int num = bytes; if (head) { /* Make small requests to get to alignment boundaries. */ - num = MIN(count, align - head); + num = MIN(bytes, align - head); if (!QEMU_IS_ALIGNED(num, bs->bl.request_alignment)) { num %= bs->bl.request_alignment; } @@ -2524,7 +2358,7 @@ int coroutine_fn bdrv_co_pdiscard(BlockDriverState *bs, int64_t offset, } offset += num; - count -= num; + bytes -= num; } ret = 0; out: @@ -2536,13 +2370,13 @@ out: return ret; } -int bdrv_pdiscard(BlockDriverState *bs, int64_t offset, int count) +int bdrv_pdiscard(BlockDriverState *bs, int64_t offset, int bytes) { Coroutine *co; DiscardCo rwco = { .bs = bs, .offset = offset, - .count = count, + .bytes = bytes, .ret = NOT_DONE, }; |