161007b31SStefan Hajnoczi /* 261007b31SStefan Hajnoczi * Block layer I/O functions 361007b31SStefan Hajnoczi * 461007b31SStefan Hajnoczi * Copyright (c) 2003 Fabrice Bellard 561007b31SStefan Hajnoczi * 661007b31SStefan Hajnoczi * Permission is hereby granted, free of charge, to any person obtaining a copy 761007b31SStefan Hajnoczi * of this software and associated documentation files (the "Software"), to deal 861007b31SStefan Hajnoczi * in the Software without restriction, including without limitation the rights 961007b31SStefan Hajnoczi * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 1061007b31SStefan Hajnoczi * copies of the Software, and to permit persons to whom the Software is 1161007b31SStefan Hajnoczi * furnished to do so, subject to the following conditions: 1261007b31SStefan Hajnoczi * 1361007b31SStefan Hajnoczi * The above copyright notice and this permission notice shall be included in 1461007b31SStefan Hajnoczi * all copies or substantial portions of the Software. 1561007b31SStefan Hajnoczi * 1661007b31SStefan Hajnoczi * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 1761007b31SStefan Hajnoczi * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 1861007b31SStefan Hajnoczi * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 1961007b31SStefan Hajnoczi * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 2061007b31SStefan Hajnoczi * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 2161007b31SStefan Hajnoczi * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN 2261007b31SStefan Hajnoczi * THE SOFTWARE. 2361007b31SStefan Hajnoczi */ 2461007b31SStefan Hajnoczi 2561007b31SStefan Hajnoczi #include "trace.h" 2661007b31SStefan Hajnoczi #include "block/blockjob.h" 2761007b31SStefan Hajnoczi #include "block/block_int.h" 28*76f4afb4SAlberto Garcia #include "block/throttle-groups.h" 2961007b31SStefan Hajnoczi 3061007b31SStefan Hajnoczi #define NOT_DONE 0x7fffffff /* used while emulated sync operation in progress */ 3161007b31SStefan Hajnoczi 3261007b31SStefan Hajnoczi static BlockAIOCB *bdrv_aio_readv_em(BlockDriverState *bs, 3361007b31SStefan Hajnoczi int64_t sector_num, QEMUIOVector *qiov, int nb_sectors, 3461007b31SStefan Hajnoczi BlockCompletionFunc *cb, void *opaque); 3561007b31SStefan Hajnoczi static BlockAIOCB *bdrv_aio_writev_em(BlockDriverState *bs, 3661007b31SStefan Hajnoczi int64_t sector_num, QEMUIOVector *qiov, int nb_sectors, 3761007b31SStefan Hajnoczi BlockCompletionFunc *cb, void *opaque); 3861007b31SStefan Hajnoczi static int coroutine_fn bdrv_co_readv_em(BlockDriverState *bs, 3961007b31SStefan Hajnoczi int64_t sector_num, int nb_sectors, 4061007b31SStefan Hajnoczi QEMUIOVector *iov); 4161007b31SStefan Hajnoczi static int coroutine_fn bdrv_co_writev_em(BlockDriverState *bs, 4261007b31SStefan Hajnoczi int64_t sector_num, int nb_sectors, 4361007b31SStefan Hajnoczi QEMUIOVector *iov); 4461007b31SStefan Hajnoczi static int coroutine_fn bdrv_co_do_preadv(BlockDriverState *bs, 4561007b31SStefan Hajnoczi int64_t offset, unsigned int bytes, QEMUIOVector *qiov, 4661007b31SStefan Hajnoczi BdrvRequestFlags flags); 4761007b31SStefan Hajnoczi static int coroutine_fn bdrv_co_do_pwritev(BlockDriverState *bs, 4861007b31SStefan Hajnoczi int64_t offset, unsigned int bytes, QEMUIOVector *qiov, 4961007b31SStefan Hajnoczi BdrvRequestFlags flags); 5061007b31SStefan Hajnoczi static BlockAIOCB *bdrv_co_aio_rw_vector(BlockDriverState *bs, 5161007b31SStefan Hajnoczi int64_t sector_num, 5261007b31SStefan Hajnoczi QEMUIOVector *qiov, 5361007b31SStefan Hajnoczi int nb_sectors, 5461007b31SStefan Hajnoczi BdrvRequestFlags flags, 5561007b31SStefan Hajnoczi BlockCompletionFunc *cb, 5661007b31SStefan Hajnoczi void *opaque, 5761007b31SStefan Hajnoczi bool is_write); 5861007b31SStefan Hajnoczi static void coroutine_fn bdrv_co_do_rw(void *opaque); 5961007b31SStefan Hajnoczi static int coroutine_fn bdrv_co_do_write_zeroes(BlockDriverState *bs, 6061007b31SStefan Hajnoczi int64_t sector_num, int nb_sectors, BdrvRequestFlags flags); 6161007b31SStefan Hajnoczi 6261007b31SStefan Hajnoczi /* throttling disk I/O limits */ 6361007b31SStefan Hajnoczi void bdrv_set_io_limits(BlockDriverState *bs, 6461007b31SStefan Hajnoczi ThrottleConfig *cfg) 6561007b31SStefan Hajnoczi { 6661007b31SStefan Hajnoczi int i; 6761007b31SStefan Hajnoczi 68*76f4afb4SAlberto Garcia throttle_group_config(bs, cfg); 6961007b31SStefan Hajnoczi 7061007b31SStefan Hajnoczi for (i = 0; i < 2; i++) { 7161007b31SStefan Hajnoczi qemu_co_enter_next(&bs->throttled_reqs[i]); 7261007b31SStefan Hajnoczi } 7361007b31SStefan Hajnoczi } 7461007b31SStefan Hajnoczi 7561007b31SStefan Hajnoczi /* this function drain all the throttled IOs */ 7661007b31SStefan Hajnoczi static bool bdrv_start_throttled_reqs(BlockDriverState *bs) 7761007b31SStefan Hajnoczi { 7861007b31SStefan Hajnoczi bool drained = false; 7961007b31SStefan Hajnoczi bool enabled = bs->io_limits_enabled; 8061007b31SStefan Hajnoczi int i; 8161007b31SStefan Hajnoczi 8261007b31SStefan Hajnoczi bs->io_limits_enabled = false; 8361007b31SStefan Hajnoczi 8461007b31SStefan Hajnoczi for (i = 0; i < 2; i++) { 8561007b31SStefan Hajnoczi while (qemu_co_enter_next(&bs->throttled_reqs[i])) { 8661007b31SStefan Hajnoczi drained = true; 8761007b31SStefan Hajnoczi } 8861007b31SStefan Hajnoczi } 8961007b31SStefan Hajnoczi 9061007b31SStefan Hajnoczi bs->io_limits_enabled = enabled; 9161007b31SStefan Hajnoczi 9261007b31SStefan Hajnoczi return drained; 9361007b31SStefan Hajnoczi } 9461007b31SStefan Hajnoczi 9561007b31SStefan Hajnoczi void bdrv_io_limits_disable(BlockDriverState *bs) 9661007b31SStefan Hajnoczi { 9761007b31SStefan Hajnoczi bs->io_limits_enabled = false; 9861007b31SStefan Hajnoczi bdrv_start_throttled_reqs(bs); 99*76f4afb4SAlberto Garcia throttle_group_unregister_bs(bs); 10061007b31SStefan Hajnoczi } 10161007b31SStefan Hajnoczi 10261007b31SStefan Hajnoczi /* should be called before bdrv_set_io_limits if a limit is set */ 103*76f4afb4SAlberto Garcia void bdrv_io_limits_enable(BlockDriverState *bs, const char *group) 10461007b31SStefan Hajnoczi { 10561007b31SStefan Hajnoczi assert(!bs->io_limits_enabled); 106*76f4afb4SAlberto Garcia throttle_group_register_bs(bs, group); 10761007b31SStefan Hajnoczi bs->io_limits_enabled = true; 10861007b31SStefan Hajnoczi } 10961007b31SStefan Hajnoczi 110*76f4afb4SAlberto Garcia void bdrv_io_limits_update_group(BlockDriverState *bs, const char *group) 11161007b31SStefan Hajnoczi { 112*76f4afb4SAlberto Garcia /* this bs is not part of any group */ 113*76f4afb4SAlberto Garcia if (!bs->throttle_state) { 11461007b31SStefan Hajnoczi return; 11561007b31SStefan Hajnoczi } 11661007b31SStefan Hajnoczi 117*76f4afb4SAlberto Garcia /* this bs is a part of the same group than the one we want */ 118*76f4afb4SAlberto Garcia if (!g_strcmp0(throttle_group_get_name(bs), group)) { 119*76f4afb4SAlberto Garcia return; 120*76f4afb4SAlberto Garcia } 121*76f4afb4SAlberto Garcia 122*76f4afb4SAlberto Garcia /* need to change the group this bs belong to */ 123*76f4afb4SAlberto Garcia bdrv_io_limits_disable(bs); 124*76f4afb4SAlberto Garcia bdrv_io_limits_enable(bs, group); 12561007b31SStefan Hajnoczi } 12661007b31SStefan Hajnoczi 12761007b31SStefan Hajnoczi void bdrv_setup_io_funcs(BlockDriver *bdrv) 12861007b31SStefan Hajnoczi { 12961007b31SStefan Hajnoczi /* Block drivers without coroutine functions need emulation */ 13061007b31SStefan Hajnoczi if (!bdrv->bdrv_co_readv) { 13161007b31SStefan Hajnoczi bdrv->bdrv_co_readv = bdrv_co_readv_em; 13261007b31SStefan Hajnoczi bdrv->bdrv_co_writev = bdrv_co_writev_em; 13361007b31SStefan Hajnoczi 13461007b31SStefan Hajnoczi /* bdrv_co_readv_em()/brdv_co_writev_em() work in terms of aio, so if 13561007b31SStefan Hajnoczi * the block driver lacks aio we need to emulate that too. 13661007b31SStefan Hajnoczi */ 13761007b31SStefan Hajnoczi if (!bdrv->bdrv_aio_readv) { 13861007b31SStefan Hajnoczi /* add AIO emulation layer */ 13961007b31SStefan Hajnoczi bdrv->bdrv_aio_readv = bdrv_aio_readv_em; 14061007b31SStefan Hajnoczi bdrv->bdrv_aio_writev = bdrv_aio_writev_em; 14161007b31SStefan Hajnoczi } 14261007b31SStefan Hajnoczi } 14361007b31SStefan Hajnoczi } 14461007b31SStefan Hajnoczi 14561007b31SStefan Hajnoczi void bdrv_refresh_limits(BlockDriverState *bs, Error **errp) 14661007b31SStefan Hajnoczi { 14761007b31SStefan Hajnoczi BlockDriver *drv = bs->drv; 14861007b31SStefan Hajnoczi Error *local_err = NULL; 14961007b31SStefan Hajnoczi 15061007b31SStefan Hajnoczi memset(&bs->bl, 0, sizeof(bs->bl)); 15161007b31SStefan Hajnoczi 15261007b31SStefan Hajnoczi if (!drv) { 15361007b31SStefan Hajnoczi return; 15461007b31SStefan Hajnoczi } 15561007b31SStefan Hajnoczi 15661007b31SStefan Hajnoczi /* Take some limits from the children as a default */ 15761007b31SStefan Hajnoczi if (bs->file) { 15861007b31SStefan Hajnoczi bdrv_refresh_limits(bs->file, &local_err); 15961007b31SStefan Hajnoczi if (local_err) { 16061007b31SStefan Hajnoczi error_propagate(errp, local_err); 16161007b31SStefan Hajnoczi return; 16261007b31SStefan Hajnoczi } 16361007b31SStefan Hajnoczi bs->bl.opt_transfer_length = bs->file->bl.opt_transfer_length; 16461007b31SStefan Hajnoczi bs->bl.max_transfer_length = bs->file->bl.max_transfer_length; 1654196d2f0SDenis V. Lunev bs->bl.min_mem_alignment = bs->file->bl.min_mem_alignment; 16661007b31SStefan Hajnoczi bs->bl.opt_mem_alignment = bs->file->bl.opt_mem_alignment; 16761007b31SStefan Hajnoczi } else { 1684196d2f0SDenis V. Lunev bs->bl.min_mem_alignment = 512; 169459b4e66SDenis V. Lunev bs->bl.opt_mem_alignment = getpagesize(); 17061007b31SStefan Hajnoczi } 17161007b31SStefan Hajnoczi 17261007b31SStefan Hajnoczi if (bs->backing_hd) { 17361007b31SStefan Hajnoczi bdrv_refresh_limits(bs->backing_hd, &local_err); 17461007b31SStefan Hajnoczi if (local_err) { 17561007b31SStefan Hajnoczi error_propagate(errp, local_err); 17661007b31SStefan Hajnoczi return; 17761007b31SStefan Hajnoczi } 17861007b31SStefan Hajnoczi bs->bl.opt_transfer_length = 17961007b31SStefan Hajnoczi MAX(bs->bl.opt_transfer_length, 18061007b31SStefan Hajnoczi bs->backing_hd->bl.opt_transfer_length); 18161007b31SStefan Hajnoczi bs->bl.max_transfer_length = 18261007b31SStefan Hajnoczi MIN_NON_ZERO(bs->bl.max_transfer_length, 18361007b31SStefan Hajnoczi bs->backing_hd->bl.max_transfer_length); 18461007b31SStefan Hajnoczi bs->bl.opt_mem_alignment = 18561007b31SStefan Hajnoczi MAX(bs->bl.opt_mem_alignment, 18661007b31SStefan Hajnoczi bs->backing_hd->bl.opt_mem_alignment); 1874196d2f0SDenis V. Lunev bs->bl.min_mem_alignment = 1884196d2f0SDenis V. Lunev MAX(bs->bl.min_mem_alignment, 1894196d2f0SDenis V. Lunev bs->backing_hd->bl.min_mem_alignment); 19061007b31SStefan Hajnoczi } 19161007b31SStefan Hajnoczi 19261007b31SStefan Hajnoczi /* Then let the driver override it */ 19361007b31SStefan Hajnoczi if (drv->bdrv_refresh_limits) { 19461007b31SStefan Hajnoczi drv->bdrv_refresh_limits(bs, errp); 19561007b31SStefan Hajnoczi } 19661007b31SStefan Hajnoczi } 19761007b31SStefan Hajnoczi 19861007b31SStefan Hajnoczi /** 19961007b31SStefan Hajnoczi * The copy-on-read flag is actually a reference count so multiple users may 20061007b31SStefan Hajnoczi * use the feature without worrying about clobbering its previous state. 20161007b31SStefan Hajnoczi * Copy-on-read stays enabled until all users have called to disable it. 20261007b31SStefan Hajnoczi */ 20361007b31SStefan Hajnoczi void bdrv_enable_copy_on_read(BlockDriverState *bs) 20461007b31SStefan Hajnoczi { 20561007b31SStefan Hajnoczi bs->copy_on_read++; 20661007b31SStefan Hajnoczi } 20761007b31SStefan Hajnoczi 20861007b31SStefan Hajnoczi void bdrv_disable_copy_on_read(BlockDriverState *bs) 20961007b31SStefan Hajnoczi { 21061007b31SStefan Hajnoczi assert(bs->copy_on_read > 0); 21161007b31SStefan Hajnoczi bs->copy_on_read--; 21261007b31SStefan Hajnoczi } 21361007b31SStefan Hajnoczi 21461007b31SStefan Hajnoczi /* Check if any requests are in-flight (including throttled requests) */ 21561007b31SStefan Hajnoczi static bool bdrv_requests_pending(BlockDriverState *bs) 21661007b31SStefan Hajnoczi { 21761007b31SStefan Hajnoczi if (!QLIST_EMPTY(&bs->tracked_requests)) { 21861007b31SStefan Hajnoczi return true; 21961007b31SStefan Hajnoczi } 22061007b31SStefan Hajnoczi if (!qemu_co_queue_empty(&bs->throttled_reqs[0])) { 22161007b31SStefan Hajnoczi return true; 22261007b31SStefan Hajnoczi } 22361007b31SStefan Hajnoczi if (!qemu_co_queue_empty(&bs->throttled_reqs[1])) { 22461007b31SStefan Hajnoczi return true; 22561007b31SStefan Hajnoczi } 22661007b31SStefan Hajnoczi if (bs->file && bdrv_requests_pending(bs->file)) { 22761007b31SStefan Hajnoczi return true; 22861007b31SStefan Hajnoczi } 22961007b31SStefan Hajnoczi if (bs->backing_hd && bdrv_requests_pending(bs->backing_hd)) { 23061007b31SStefan Hajnoczi return true; 23161007b31SStefan Hajnoczi } 23261007b31SStefan Hajnoczi return false; 23361007b31SStefan Hajnoczi } 23461007b31SStefan Hajnoczi 23561007b31SStefan Hajnoczi static bool bdrv_drain_one(BlockDriverState *bs) 23661007b31SStefan Hajnoczi { 23761007b31SStefan Hajnoczi bool bs_busy; 23861007b31SStefan Hajnoczi 23961007b31SStefan Hajnoczi bdrv_flush_io_queue(bs); 24061007b31SStefan Hajnoczi bdrv_start_throttled_reqs(bs); 24161007b31SStefan Hajnoczi bs_busy = bdrv_requests_pending(bs); 24261007b31SStefan Hajnoczi bs_busy |= aio_poll(bdrv_get_aio_context(bs), bs_busy); 24361007b31SStefan Hajnoczi return bs_busy; 24461007b31SStefan Hajnoczi } 24561007b31SStefan Hajnoczi 24661007b31SStefan Hajnoczi /* 24761007b31SStefan Hajnoczi * Wait for pending requests to complete on a single BlockDriverState subtree 24861007b31SStefan Hajnoczi * 24961007b31SStefan Hajnoczi * See the warning in bdrv_drain_all(). This function can only be called if 25061007b31SStefan Hajnoczi * you are sure nothing can generate I/O because you have op blockers 25161007b31SStefan Hajnoczi * installed. 25261007b31SStefan Hajnoczi * 25361007b31SStefan Hajnoczi * Note that unlike bdrv_drain_all(), the caller must hold the BlockDriverState 25461007b31SStefan Hajnoczi * AioContext. 25561007b31SStefan Hajnoczi */ 25661007b31SStefan Hajnoczi void bdrv_drain(BlockDriverState *bs) 25761007b31SStefan Hajnoczi { 25861007b31SStefan Hajnoczi while (bdrv_drain_one(bs)) { 25961007b31SStefan Hajnoczi /* Keep iterating */ 26061007b31SStefan Hajnoczi } 26161007b31SStefan Hajnoczi } 26261007b31SStefan Hajnoczi 26361007b31SStefan Hajnoczi /* 26461007b31SStefan Hajnoczi * Wait for pending requests to complete across all BlockDriverStates 26561007b31SStefan Hajnoczi * 26661007b31SStefan Hajnoczi * This function does not flush data to disk, use bdrv_flush_all() for that 26761007b31SStefan Hajnoczi * after calling this function. 26861007b31SStefan Hajnoczi * 26961007b31SStefan Hajnoczi * Note that completion of an asynchronous I/O operation can trigger any 27061007b31SStefan Hajnoczi * number of other I/O operations on other devices---for example a coroutine 27161007b31SStefan Hajnoczi * can be arbitrarily complex and a constant flow of I/O can come until the 27261007b31SStefan Hajnoczi * coroutine is complete. Because of this, it is not possible to have a 27361007b31SStefan Hajnoczi * function to drain a single device's I/O queue. 27461007b31SStefan Hajnoczi */ 27561007b31SStefan Hajnoczi void bdrv_drain_all(void) 27661007b31SStefan Hajnoczi { 27761007b31SStefan Hajnoczi /* Always run first iteration so any pending completion BHs run */ 27861007b31SStefan Hajnoczi bool busy = true; 27961007b31SStefan Hajnoczi BlockDriverState *bs = NULL; 28061007b31SStefan Hajnoczi 28161007b31SStefan Hajnoczi while ((bs = bdrv_next(bs))) { 28261007b31SStefan Hajnoczi AioContext *aio_context = bdrv_get_aio_context(bs); 28361007b31SStefan Hajnoczi 28461007b31SStefan Hajnoczi aio_context_acquire(aio_context); 28561007b31SStefan Hajnoczi if (bs->job) { 28661007b31SStefan Hajnoczi block_job_pause(bs->job); 28761007b31SStefan Hajnoczi } 28861007b31SStefan Hajnoczi aio_context_release(aio_context); 28961007b31SStefan Hajnoczi } 29061007b31SStefan Hajnoczi 29161007b31SStefan Hajnoczi while (busy) { 29261007b31SStefan Hajnoczi busy = false; 29361007b31SStefan Hajnoczi bs = NULL; 29461007b31SStefan Hajnoczi 29561007b31SStefan Hajnoczi while ((bs = bdrv_next(bs))) { 29661007b31SStefan Hajnoczi AioContext *aio_context = bdrv_get_aio_context(bs); 29761007b31SStefan Hajnoczi 29861007b31SStefan Hajnoczi aio_context_acquire(aio_context); 29961007b31SStefan Hajnoczi busy |= bdrv_drain_one(bs); 30061007b31SStefan Hajnoczi aio_context_release(aio_context); 30161007b31SStefan Hajnoczi } 30261007b31SStefan Hajnoczi } 30361007b31SStefan Hajnoczi 30461007b31SStefan Hajnoczi bs = NULL; 30561007b31SStefan Hajnoczi while ((bs = bdrv_next(bs))) { 30661007b31SStefan Hajnoczi AioContext *aio_context = bdrv_get_aio_context(bs); 30761007b31SStefan Hajnoczi 30861007b31SStefan Hajnoczi aio_context_acquire(aio_context); 30961007b31SStefan Hajnoczi if (bs->job) { 31061007b31SStefan Hajnoczi block_job_resume(bs->job); 31161007b31SStefan Hajnoczi } 31261007b31SStefan Hajnoczi aio_context_release(aio_context); 31361007b31SStefan Hajnoczi } 31461007b31SStefan Hajnoczi } 31561007b31SStefan Hajnoczi 31661007b31SStefan Hajnoczi /** 31761007b31SStefan Hajnoczi * Remove an active request from the tracked requests list 31861007b31SStefan Hajnoczi * 31961007b31SStefan Hajnoczi * This function should be called when a tracked request is completing. 32061007b31SStefan Hajnoczi */ 32161007b31SStefan Hajnoczi static void tracked_request_end(BdrvTrackedRequest *req) 32261007b31SStefan Hajnoczi { 32361007b31SStefan Hajnoczi if (req->serialising) { 32461007b31SStefan Hajnoczi req->bs->serialising_in_flight--; 32561007b31SStefan Hajnoczi } 32661007b31SStefan Hajnoczi 32761007b31SStefan Hajnoczi QLIST_REMOVE(req, list); 32861007b31SStefan Hajnoczi qemu_co_queue_restart_all(&req->wait_queue); 32961007b31SStefan Hajnoczi } 33061007b31SStefan Hajnoczi 33161007b31SStefan Hajnoczi /** 33261007b31SStefan Hajnoczi * Add an active request to the tracked requests list 33361007b31SStefan Hajnoczi */ 33461007b31SStefan Hajnoczi static void tracked_request_begin(BdrvTrackedRequest *req, 33561007b31SStefan Hajnoczi BlockDriverState *bs, 33661007b31SStefan Hajnoczi int64_t offset, 33761007b31SStefan Hajnoczi unsigned int bytes, bool is_write) 33861007b31SStefan Hajnoczi { 33961007b31SStefan Hajnoczi *req = (BdrvTrackedRequest){ 34061007b31SStefan Hajnoczi .bs = bs, 34161007b31SStefan Hajnoczi .offset = offset, 34261007b31SStefan Hajnoczi .bytes = bytes, 34361007b31SStefan Hajnoczi .is_write = is_write, 34461007b31SStefan Hajnoczi .co = qemu_coroutine_self(), 34561007b31SStefan Hajnoczi .serialising = false, 34661007b31SStefan Hajnoczi .overlap_offset = offset, 34761007b31SStefan Hajnoczi .overlap_bytes = bytes, 34861007b31SStefan Hajnoczi }; 34961007b31SStefan Hajnoczi 35061007b31SStefan Hajnoczi qemu_co_queue_init(&req->wait_queue); 35161007b31SStefan Hajnoczi 35261007b31SStefan Hajnoczi QLIST_INSERT_HEAD(&bs->tracked_requests, req, list); 35361007b31SStefan Hajnoczi } 35461007b31SStefan Hajnoczi 35561007b31SStefan Hajnoczi static void mark_request_serialising(BdrvTrackedRequest *req, uint64_t align) 35661007b31SStefan Hajnoczi { 35761007b31SStefan Hajnoczi int64_t overlap_offset = req->offset & ~(align - 1); 35861007b31SStefan Hajnoczi unsigned int overlap_bytes = ROUND_UP(req->offset + req->bytes, align) 35961007b31SStefan Hajnoczi - overlap_offset; 36061007b31SStefan Hajnoczi 36161007b31SStefan Hajnoczi if (!req->serialising) { 36261007b31SStefan Hajnoczi req->bs->serialising_in_flight++; 36361007b31SStefan Hajnoczi req->serialising = true; 36461007b31SStefan Hajnoczi } 36561007b31SStefan Hajnoczi 36661007b31SStefan Hajnoczi req->overlap_offset = MIN(req->overlap_offset, overlap_offset); 36761007b31SStefan Hajnoczi req->overlap_bytes = MAX(req->overlap_bytes, overlap_bytes); 36861007b31SStefan Hajnoczi } 36961007b31SStefan Hajnoczi 37061007b31SStefan Hajnoczi /** 37161007b31SStefan Hajnoczi * Round a region to cluster boundaries 37261007b31SStefan Hajnoczi */ 37361007b31SStefan Hajnoczi void bdrv_round_to_clusters(BlockDriverState *bs, 37461007b31SStefan Hajnoczi int64_t sector_num, int nb_sectors, 37561007b31SStefan Hajnoczi int64_t *cluster_sector_num, 37661007b31SStefan Hajnoczi int *cluster_nb_sectors) 37761007b31SStefan Hajnoczi { 37861007b31SStefan Hajnoczi BlockDriverInfo bdi; 37961007b31SStefan Hajnoczi 38061007b31SStefan Hajnoczi if (bdrv_get_info(bs, &bdi) < 0 || bdi.cluster_size == 0) { 38161007b31SStefan Hajnoczi *cluster_sector_num = sector_num; 38261007b31SStefan Hajnoczi *cluster_nb_sectors = nb_sectors; 38361007b31SStefan Hajnoczi } else { 38461007b31SStefan Hajnoczi int64_t c = bdi.cluster_size / BDRV_SECTOR_SIZE; 38561007b31SStefan Hajnoczi *cluster_sector_num = QEMU_ALIGN_DOWN(sector_num, c); 38661007b31SStefan Hajnoczi *cluster_nb_sectors = QEMU_ALIGN_UP(sector_num - *cluster_sector_num + 38761007b31SStefan Hajnoczi nb_sectors, c); 38861007b31SStefan Hajnoczi } 38961007b31SStefan Hajnoczi } 39061007b31SStefan Hajnoczi 39161007b31SStefan Hajnoczi static int bdrv_get_cluster_size(BlockDriverState *bs) 39261007b31SStefan Hajnoczi { 39361007b31SStefan Hajnoczi BlockDriverInfo bdi; 39461007b31SStefan Hajnoczi int ret; 39561007b31SStefan Hajnoczi 39661007b31SStefan Hajnoczi ret = bdrv_get_info(bs, &bdi); 39761007b31SStefan Hajnoczi if (ret < 0 || bdi.cluster_size == 0) { 39861007b31SStefan Hajnoczi return bs->request_alignment; 39961007b31SStefan Hajnoczi } else { 40061007b31SStefan Hajnoczi return bdi.cluster_size; 40161007b31SStefan Hajnoczi } 40261007b31SStefan Hajnoczi } 40361007b31SStefan Hajnoczi 40461007b31SStefan Hajnoczi static bool tracked_request_overlaps(BdrvTrackedRequest *req, 40561007b31SStefan Hajnoczi int64_t offset, unsigned int bytes) 40661007b31SStefan Hajnoczi { 40761007b31SStefan Hajnoczi /* aaaa bbbb */ 40861007b31SStefan Hajnoczi if (offset >= req->overlap_offset + req->overlap_bytes) { 40961007b31SStefan Hajnoczi return false; 41061007b31SStefan Hajnoczi } 41161007b31SStefan Hajnoczi /* bbbb aaaa */ 41261007b31SStefan Hajnoczi if (req->overlap_offset >= offset + bytes) { 41361007b31SStefan Hajnoczi return false; 41461007b31SStefan Hajnoczi } 41561007b31SStefan Hajnoczi return true; 41661007b31SStefan Hajnoczi } 41761007b31SStefan Hajnoczi 41861007b31SStefan Hajnoczi static bool coroutine_fn wait_serialising_requests(BdrvTrackedRequest *self) 41961007b31SStefan Hajnoczi { 42061007b31SStefan Hajnoczi BlockDriverState *bs = self->bs; 42161007b31SStefan Hajnoczi BdrvTrackedRequest *req; 42261007b31SStefan Hajnoczi bool retry; 42361007b31SStefan Hajnoczi bool waited = false; 42461007b31SStefan Hajnoczi 42561007b31SStefan Hajnoczi if (!bs->serialising_in_flight) { 42661007b31SStefan Hajnoczi return false; 42761007b31SStefan Hajnoczi } 42861007b31SStefan Hajnoczi 42961007b31SStefan Hajnoczi do { 43061007b31SStefan Hajnoczi retry = false; 43161007b31SStefan Hajnoczi QLIST_FOREACH(req, &bs->tracked_requests, list) { 43261007b31SStefan Hajnoczi if (req == self || (!req->serialising && !self->serialising)) { 43361007b31SStefan Hajnoczi continue; 43461007b31SStefan Hajnoczi } 43561007b31SStefan Hajnoczi if (tracked_request_overlaps(req, self->overlap_offset, 43661007b31SStefan Hajnoczi self->overlap_bytes)) 43761007b31SStefan Hajnoczi { 43861007b31SStefan Hajnoczi /* Hitting this means there was a reentrant request, for 43961007b31SStefan Hajnoczi * example, a block driver issuing nested requests. This must 44061007b31SStefan Hajnoczi * never happen since it means deadlock. 44161007b31SStefan Hajnoczi */ 44261007b31SStefan Hajnoczi assert(qemu_coroutine_self() != req->co); 44361007b31SStefan Hajnoczi 44461007b31SStefan Hajnoczi /* If the request is already (indirectly) waiting for us, or 44561007b31SStefan Hajnoczi * will wait for us as soon as it wakes up, then just go on 44661007b31SStefan Hajnoczi * (instead of producing a deadlock in the former case). */ 44761007b31SStefan Hajnoczi if (!req->waiting_for) { 44861007b31SStefan Hajnoczi self->waiting_for = req; 44961007b31SStefan Hajnoczi qemu_co_queue_wait(&req->wait_queue); 45061007b31SStefan Hajnoczi self->waiting_for = NULL; 45161007b31SStefan Hajnoczi retry = true; 45261007b31SStefan Hajnoczi waited = true; 45361007b31SStefan Hajnoczi break; 45461007b31SStefan Hajnoczi } 45561007b31SStefan Hajnoczi } 45661007b31SStefan Hajnoczi } 45761007b31SStefan Hajnoczi } while (retry); 45861007b31SStefan Hajnoczi 45961007b31SStefan Hajnoczi return waited; 46061007b31SStefan Hajnoczi } 46161007b31SStefan Hajnoczi 46261007b31SStefan Hajnoczi static int bdrv_check_byte_request(BlockDriverState *bs, int64_t offset, 46361007b31SStefan Hajnoczi size_t size) 46461007b31SStefan Hajnoczi { 46561007b31SStefan Hajnoczi if (size > BDRV_REQUEST_MAX_SECTORS << BDRV_SECTOR_BITS) { 46661007b31SStefan Hajnoczi return -EIO; 46761007b31SStefan Hajnoczi } 46861007b31SStefan Hajnoczi 46961007b31SStefan Hajnoczi if (!bdrv_is_inserted(bs)) { 47061007b31SStefan Hajnoczi return -ENOMEDIUM; 47161007b31SStefan Hajnoczi } 47261007b31SStefan Hajnoczi 47361007b31SStefan Hajnoczi if (offset < 0) { 47461007b31SStefan Hajnoczi return -EIO; 47561007b31SStefan Hajnoczi } 47661007b31SStefan Hajnoczi 47761007b31SStefan Hajnoczi return 0; 47861007b31SStefan Hajnoczi } 47961007b31SStefan Hajnoczi 48061007b31SStefan Hajnoczi static int bdrv_check_request(BlockDriverState *bs, int64_t sector_num, 48161007b31SStefan Hajnoczi int nb_sectors) 48261007b31SStefan Hajnoczi { 48361007b31SStefan Hajnoczi if (nb_sectors < 0 || nb_sectors > BDRV_REQUEST_MAX_SECTORS) { 48461007b31SStefan Hajnoczi return -EIO; 48561007b31SStefan Hajnoczi } 48661007b31SStefan Hajnoczi 48761007b31SStefan Hajnoczi return bdrv_check_byte_request(bs, sector_num * BDRV_SECTOR_SIZE, 48861007b31SStefan Hajnoczi nb_sectors * BDRV_SECTOR_SIZE); 48961007b31SStefan Hajnoczi } 49061007b31SStefan Hajnoczi 49161007b31SStefan Hajnoczi typedef struct RwCo { 49261007b31SStefan Hajnoczi BlockDriverState *bs; 49361007b31SStefan Hajnoczi int64_t offset; 49461007b31SStefan Hajnoczi QEMUIOVector *qiov; 49561007b31SStefan Hajnoczi bool is_write; 49661007b31SStefan Hajnoczi int ret; 49761007b31SStefan Hajnoczi BdrvRequestFlags flags; 49861007b31SStefan Hajnoczi } RwCo; 49961007b31SStefan Hajnoczi 50061007b31SStefan Hajnoczi static void coroutine_fn bdrv_rw_co_entry(void *opaque) 50161007b31SStefan Hajnoczi { 50261007b31SStefan Hajnoczi RwCo *rwco = opaque; 50361007b31SStefan Hajnoczi 50461007b31SStefan Hajnoczi if (!rwco->is_write) { 50561007b31SStefan Hajnoczi rwco->ret = bdrv_co_do_preadv(rwco->bs, rwco->offset, 50661007b31SStefan Hajnoczi rwco->qiov->size, rwco->qiov, 50761007b31SStefan Hajnoczi rwco->flags); 50861007b31SStefan Hajnoczi } else { 50961007b31SStefan Hajnoczi rwco->ret = bdrv_co_do_pwritev(rwco->bs, rwco->offset, 51061007b31SStefan Hajnoczi rwco->qiov->size, rwco->qiov, 51161007b31SStefan Hajnoczi rwco->flags); 51261007b31SStefan Hajnoczi } 51361007b31SStefan Hajnoczi } 51461007b31SStefan Hajnoczi 51561007b31SStefan Hajnoczi /* 51661007b31SStefan Hajnoczi * Process a vectored synchronous request using coroutines 51761007b31SStefan Hajnoczi */ 51861007b31SStefan Hajnoczi static int bdrv_prwv_co(BlockDriverState *bs, int64_t offset, 51961007b31SStefan Hajnoczi QEMUIOVector *qiov, bool is_write, 52061007b31SStefan Hajnoczi BdrvRequestFlags flags) 52161007b31SStefan Hajnoczi { 52261007b31SStefan Hajnoczi Coroutine *co; 52361007b31SStefan Hajnoczi RwCo rwco = { 52461007b31SStefan Hajnoczi .bs = bs, 52561007b31SStefan Hajnoczi .offset = offset, 52661007b31SStefan Hajnoczi .qiov = qiov, 52761007b31SStefan Hajnoczi .is_write = is_write, 52861007b31SStefan Hajnoczi .ret = NOT_DONE, 52961007b31SStefan Hajnoczi .flags = flags, 53061007b31SStefan Hajnoczi }; 53161007b31SStefan Hajnoczi 53261007b31SStefan Hajnoczi /** 53361007b31SStefan Hajnoczi * In sync call context, when the vcpu is blocked, this throttling timer 53461007b31SStefan Hajnoczi * will not fire; so the I/O throttling function has to be disabled here 53561007b31SStefan Hajnoczi * if it has been enabled. 53661007b31SStefan Hajnoczi */ 53761007b31SStefan Hajnoczi if (bs->io_limits_enabled) { 53861007b31SStefan Hajnoczi fprintf(stderr, "Disabling I/O throttling on '%s' due " 53961007b31SStefan Hajnoczi "to synchronous I/O.\n", bdrv_get_device_name(bs)); 54061007b31SStefan Hajnoczi bdrv_io_limits_disable(bs); 54161007b31SStefan Hajnoczi } 54261007b31SStefan Hajnoczi 54361007b31SStefan Hajnoczi if (qemu_in_coroutine()) { 54461007b31SStefan Hajnoczi /* Fast-path if already in coroutine context */ 54561007b31SStefan Hajnoczi bdrv_rw_co_entry(&rwco); 54661007b31SStefan Hajnoczi } else { 54761007b31SStefan Hajnoczi AioContext *aio_context = bdrv_get_aio_context(bs); 54861007b31SStefan Hajnoczi 54961007b31SStefan Hajnoczi co = qemu_coroutine_create(bdrv_rw_co_entry); 55061007b31SStefan Hajnoczi qemu_coroutine_enter(co, &rwco); 55161007b31SStefan Hajnoczi while (rwco.ret == NOT_DONE) { 55261007b31SStefan Hajnoczi aio_poll(aio_context, true); 55361007b31SStefan Hajnoczi } 55461007b31SStefan Hajnoczi } 55561007b31SStefan Hajnoczi return rwco.ret; 55661007b31SStefan Hajnoczi } 55761007b31SStefan Hajnoczi 55861007b31SStefan Hajnoczi /* 55961007b31SStefan Hajnoczi * Process a synchronous request using coroutines 56061007b31SStefan Hajnoczi */ 56161007b31SStefan Hajnoczi static int bdrv_rw_co(BlockDriverState *bs, int64_t sector_num, uint8_t *buf, 56261007b31SStefan Hajnoczi int nb_sectors, bool is_write, BdrvRequestFlags flags) 56361007b31SStefan Hajnoczi { 56461007b31SStefan Hajnoczi QEMUIOVector qiov; 56561007b31SStefan Hajnoczi struct iovec iov = { 56661007b31SStefan Hajnoczi .iov_base = (void *)buf, 56761007b31SStefan Hajnoczi .iov_len = nb_sectors * BDRV_SECTOR_SIZE, 56861007b31SStefan Hajnoczi }; 56961007b31SStefan Hajnoczi 57061007b31SStefan Hajnoczi if (nb_sectors < 0 || nb_sectors > BDRV_REQUEST_MAX_SECTORS) { 57161007b31SStefan Hajnoczi return -EINVAL; 57261007b31SStefan Hajnoczi } 57361007b31SStefan Hajnoczi 57461007b31SStefan Hajnoczi qemu_iovec_init_external(&qiov, &iov, 1); 57561007b31SStefan Hajnoczi return bdrv_prwv_co(bs, sector_num << BDRV_SECTOR_BITS, 57661007b31SStefan Hajnoczi &qiov, is_write, flags); 57761007b31SStefan Hajnoczi } 57861007b31SStefan Hajnoczi 57961007b31SStefan Hajnoczi /* return < 0 if error. See bdrv_write() for the return codes */ 58061007b31SStefan Hajnoczi int bdrv_read(BlockDriverState *bs, int64_t sector_num, 58161007b31SStefan Hajnoczi uint8_t *buf, int nb_sectors) 58261007b31SStefan Hajnoczi { 58361007b31SStefan Hajnoczi return bdrv_rw_co(bs, sector_num, buf, nb_sectors, false, 0); 58461007b31SStefan Hajnoczi } 58561007b31SStefan Hajnoczi 58661007b31SStefan Hajnoczi /* Just like bdrv_read(), but with I/O throttling temporarily disabled */ 58761007b31SStefan Hajnoczi int bdrv_read_unthrottled(BlockDriverState *bs, int64_t sector_num, 58861007b31SStefan Hajnoczi uint8_t *buf, int nb_sectors) 58961007b31SStefan Hajnoczi { 59061007b31SStefan Hajnoczi bool enabled; 59161007b31SStefan Hajnoczi int ret; 59261007b31SStefan Hajnoczi 59361007b31SStefan Hajnoczi enabled = bs->io_limits_enabled; 59461007b31SStefan Hajnoczi bs->io_limits_enabled = false; 59561007b31SStefan Hajnoczi ret = bdrv_read(bs, sector_num, buf, nb_sectors); 59661007b31SStefan Hajnoczi bs->io_limits_enabled = enabled; 59761007b31SStefan Hajnoczi return ret; 59861007b31SStefan Hajnoczi } 59961007b31SStefan Hajnoczi 60061007b31SStefan Hajnoczi /* Return < 0 if error. Important errors are: 60161007b31SStefan Hajnoczi -EIO generic I/O error (may happen for all errors) 60261007b31SStefan Hajnoczi -ENOMEDIUM No media inserted. 60361007b31SStefan Hajnoczi -EINVAL Invalid sector number or nb_sectors 60461007b31SStefan Hajnoczi -EACCES Trying to write a read-only device 60561007b31SStefan Hajnoczi */ 60661007b31SStefan Hajnoczi int bdrv_write(BlockDriverState *bs, int64_t sector_num, 60761007b31SStefan Hajnoczi const uint8_t *buf, int nb_sectors) 60861007b31SStefan Hajnoczi { 60961007b31SStefan Hajnoczi return bdrv_rw_co(bs, sector_num, (uint8_t *)buf, nb_sectors, true, 0); 61061007b31SStefan Hajnoczi } 61161007b31SStefan Hajnoczi 61261007b31SStefan Hajnoczi int bdrv_write_zeroes(BlockDriverState *bs, int64_t sector_num, 61361007b31SStefan Hajnoczi int nb_sectors, BdrvRequestFlags flags) 61461007b31SStefan Hajnoczi { 61561007b31SStefan Hajnoczi return bdrv_rw_co(bs, sector_num, NULL, nb_sectors, true, 61661007b31SStefan Hajnoczi BDRV_REQ_ZERO_WRITE | flags); 61761007b31SStefan Hajnoczi } 61861007b31SStefan Hajnoczi 61961007b31SStefan Hajnoczi /* 62061007b31SStefan Hajnoczi * Completely zero out a block device with the help of bdrv_write_zeroes. 62161007b31SStefan Hajnoczi * The operation is sped up by checking the block status and only writing 62261007b31SStefan Hajnoczi * zeroes to the device if they currently do not return zeroes. Optional 62361007b31SStefan Hajnoczi * flags are passed through to bdrv_write_zeroes (e.g. BDRV_REQ_MAY_UNMAP). 62461007b31SStefan Hajnoczi * 62561007b31SStefan Hajnoczi * Returns < 0 on error, 0 on success. For error codes see bdrv_write(). 62661007b31SStefan Hajnoczi */ 62761007b31SStefan Hajnoczi int bdrv_make_zero(BlockDriverState *bs, BdrvRequestFlags flags) 62861007b31SStefan Hajnoczi { 62961007b31SStefan Hajnoczi int64_t target_sectors, ret, nb_sectors, sector_num = 0; 63061007b31SStefan Hajnoczi int n; 63161007b31SStefan Hajnoczi 63261007b31SStefan Hajnoczi target_sectors = bdrv_nb_sectors(bs); 63361007b31SStefan Hajnoczi if (target_sectors < 0) { 63461007b31SStefan Hajnoczi return target_sectors; 63561007b31SStefan Hajnoczi } 63661007b31SStefan Hajnoczi 63761007b31SStefan Hajnoczi for (;;) { 63861007b31SStefan Hajnoczi nb_sectors = MIN(target_sectors - sector_num, BDRV_REQUEST_MAX_SECTORS); 63961007b31SStefan Hajnoczi if (nb_sectors <= 0) { 64061007b31SStefan Hajnoczi return 0; 64161007b31SStefan Hajnoczi } 64261007b31SStefan Hajnoczi ret = bdrv_get_block_status(bs, sector_num, nb_sectors, &n); 64361007b31SStefan Hajnoczi if (ret < 0) { 64461007b31SStefan Hajnoczi error_report("error getting block status at sector %" PRId64 ": %s", 64561007b31SStefan Hajnoczi sector_num, strerror(-ret)); 64661007b31SStefan Hajnoczi return ret; 64761007b31SStefan Hajnoczi } 64861007b31SStefan Hajnoczi if (ret & BDRV_BLOCK_ZERO) { 64961007b31SStefan Hajnoczi sector_num += n; 65061007b31SStefan Hajnoczi continue; 65161007b31SStefan Hajnoczi } 65261007b31SStefan Hajnoczi ret = bdrv_write_zeroes(bs, sector_num, n, flags); 65361007b31SStefan Hajnoczi if (ret < 0) { 65461007b31SStefan Hajnoczi error_report("error writing zeroes at sector %" PRId64 ": %s", 65561007b31SStefan Hajnoczi sector_num, strerror(-ret)); 65661007b31SStefan Hajnoczi return ret; 65761007b31SStefan Hajnoczi } 65861007b31SStefan Hajnoczi sector_num += n; 65961007b31SStefan Hajnoczi } 66061007b31SStefan Hajnoczi } 66161007b31SStefan Hajnoczi 66261007b31SStefan Hajnoczi int bdrv_pread(BlockDriverState *bs, int64_t offset, void *buf, int bytes) 66361007b31SStefan Hajnoczi { 66461007b31SStefan Hajnoczi QEMUIOVector qiov; 66561007b31SStefan Hajnoczi struct iovec iov = { 66661007b31SStefan Hajnoczi .iov_base = (void *)buf, 66761007b31SStefan Hajnoczi .iov_len = bytes, 66861007b31SStefan Hajnoczi }; 66961007b31SStefan Hajnoczi int ret; 67061007b31SStefan Hajnoczi 67161007b31SStefan Hajnoczi if (bytes < 0) { 67261007b31SStefan Hajnoczi return -EINVAL; 67361007b31SStefan Hajnoczi } 67461007b31SStefan Hajnoczi 67561007b31SStefan Hajnoczi qemu_iovec_init_external(&qiov, &iov, 1); 67661007b31SStefan Hajnoczi ret = bdrv_prwv_co(bs, offset, &qiov, false, 0); 67761007b31SStefan Hajnoczi if (ret < 0) { 67861007b31SStefan Hajnoczi return ret; 67961007b31SStefan Hajnoczi } 68061007b31SStefan Hajnoczi 68161007b31SStefan Hajnoczi return bytes; 68261007b31SStefan Hajnoczi } 68361007b31SStefan Hajnoczi 68461007b31SStefan Hajnoczi int bdrv_pwritev(BlockDriverState *bs, int64_t offset, QEMUIOVector *qiov) 68561007b31SStefan Hajnoczi { 68661007b31SStefan Hajnoczi int ret; 68761007b31SStefan Hajnoczi 68861007b31SStefan Hajnoczi ret = bdrv_prwv_co(bs, offset, qiov, true, 0); 68961007b31SStefan Hajnoczi if (ret < 0) { 69061007b31SStefan Hajnoczi return ret; 69161007b31SStefan Hajnoczi } 69261007b31SStefan Hajnoczi 69361007b31SStefan Hajnoczi return qiov->size; 69461007b31SStefan Hajnoczi } 69561007b31SStefan Hajnoczi 69661007b31SStefan Hajnoczi int bdrv_pwrite(BlockDriverState *bs, int64_t offset, 69761007b31SStefan Hajnoczi const void *buf, int bytes) 69861007b31SStefan Hajnoczi { 69961007b31SStefan Hajnoczi QEMUIOVector qiov; 70061007b31SStefan Hajnoczi struct iovec iov = { 70161007b31SStefan Hajnoczi .iov_base = (void *) buf, 70261007b31SStefan Hajnoczi .iov_len = bytes, 70361007b31SStefan Hajnoczi }; 70461007b31SStefan Hajnoczi 70561007b31SStefan Hajnoczi if (bytes < 0) { 70661007b31SStefan Hajnoczi return -EINVAL; 70761007b31SStefan Hajnoczi } 70861007b31SStefan Hajnoczi 70961007b31SStefan Hajnoczi qemu_iovec_init_external(&qiov, &iov, 1); 71061007b31SStefan Hajnoczi return bdrv_pwritev(bs, offset, &qiov); 71161007b31SStefan Hajnoczi } 71261007b31SStefan Hajnoczi 71361007b31SStefan Hajnoczi /* 71461007b31SStefan Hajnoczi * Writes to the file and ensures that no writes are reordered across this 71561007b31SStefan Hajnoczi * request (acts as a barrier) 71661007b31SStefan Hajnoczi * 71761007b31SStefan Hajnoczi * Returns 0 on success, -errno in error cases. 71861007b31SStefan Hajnoczi */ 71961007b31SStefan Hajnoczi int bdrv_pwrite_sync(BlockDriverState *bs, int64_t offset, 72061007b31SStefan Hajnoczi const void *buf, int count) 72161007b31SStefan Hajnoczi { 72261007b31SStefan Hajnoczi int ret; 72361007b31SStefan Hajnoczi 72461007b31SStefan Hajnoczi ret = bdrv_pwrite(bs, offset, buf, count); 72561007b31SStefan Hajnoczi if (ret < 0) { 72661007b31SStefan Hajnoczi return ret; 72761007b31SStefan Hajnoczi } 72861007b31SStefan Hajnoczi 72961007b31SStefan Hajnoczi /* No flush needed for cache modes that already do it */ 73061007b31SStefan Hajnoczi if (bs->enable_write_cache) { 73161007b31SStefan Hajnoczi bdrv_flush(bs); 73261007b31SStefan Hajnoczi } 73361007b31SStefan Hajnoczi 73461007b31SStefan Hajnoczi return 0; 73561007b31SStefan Hajnoczi } 73661007b31SStefan Hajnoczi 73761007b31SStefan Hajnoczi static int coroutine_fn bdrv_co_do_copy_on_readv(BlockDriverState *bs, 73861007b31SStefan Hajnoczi int64_t sector_num, int nb_sectors, QEMUIOVector *qiov) 73961007b31SStefan Hajnoczi { 74061007b31SStefan Hajnoczi /* Perform I/O through a temporary buffer so that users who scribble over 74161007b31SStefan Hajnoczi * their read buffer while the operation is in progress do not end up 74261007b31SStefan Hajnoczi * modifying the image file. This is critical for zero-copy guest I/O 74361007b31SStefan Hajnoczi * where anything might happen inside guest memory. 74461007b31SStefan Hajnoczi */ 74561007b31SStefan Hajnoczi void *bounce_buffer; 74661007b31SStefan Hajnoczi 74761007b31SStefan Hajnoczi BlockDriver *drv = bs->drv; 74861007b31SStefan Hajnoczi struct iovec iov; 74961007b31SStefan Hajnoczi QEMUIOVector bounce_qiov; 75061007b31SStefan Hajnoczi int64_t cluster_sector_num; 75161007b31SStefan Hajnoczi int cluster_nb_sectors; 75261007b31SStefan Hajnoczi size_t skip_bytes; 75361007b31SStefan Hajnoczi int ret; 75461007b31SStefan Hajnoczi 75561007b31SStefan Hajnoczi /* Cover entire cluster so no additional backing file I/O is required when 75661007b31SStefan Hajnoczi * allocating cluster in the image file. 75761007b31SStefan Hajnoczi */ 75861007b31SStefan Hajnoczi bdrv_round_to_clusters(bs, sector_num, nb_sectors, 75961007b31SStefan Hajnoczi &cluster_sector_num, &cluster_nb_sectors); 76061007b31SStefan Hajnoczi 76161007b31SStefan Hajnoczi trace_bdrv_co_do_copy_on_readv(bs, sector_num, nb_sectors, 76261007b31SStefan Hajnoczi cluster_sector_num, cluster_nb_sectors); 76361007b31SStefan Hajnoczi 76461007b31SStefan Hajnoczi iov.iov_len = cluster_nb_sectors * BDRV_SECTOR_SIZE; 76561007b31SStefan Hajnoczi iov.iov_base = bounce_buffer = qemu_try_blockalign(bs, iov.iov_len); 76661007b31SStefan Hajnoczi if (bounce_buffer == NULL) { 76761007b31SStefan Hajnoczi ret = -ENOMEM; 76861007b31SStefan Hajnoczi goto err; 76961007b31SStefan Hajnoczi } 77061007b31SStefan Hajnoczi 77161007b31SStefan Hajnoczi qemu_iovec_init_external(&bounce_qiov, &iov, 1); 77261007b31SStefan Hajnoczi 77361007b31SStefan Hajnoczi ret = drv->bdrv_co_readv(bs, cluster_sector_num, cluster_nb_sectors, 77461007b31SStefan Hajnoczi &bounce_qiov); 77561007b31SStefan Hajnoczi if (ret < 0) { 77661007b31SStefan Hajnoczi goto err; 77761007b31SStefan Hajnoczi } 77861007b31SStefan Hajnoczi 77961007b31SStefan Hajnoczi if (drv->bdrv_co_write_zeroes && 78061007b31SStefan Hajnoczi buffer_is_zero(bounce_buffer, iov.iov_len)) { 78161007b31SStefan Hajnoczi ret = bdrv_co_do_write_zeroes(bs, cluster_sector_num, 78261007b31SStefan Hajnoczi cluster_nb_sectors, 0); 78361007b31SStefan Hajnoczi } else { 78461007b31SStefan Hajnoczi /* This does not change the data on the disk, it is not necessary 78561007b31SStefan Hajnoczi * to flush even in cache=writethrough mode. 78661007b31SStefan Hajnoczi */ 78761007b31SStefan Hajnoczi ret = drv->bdrv_co_writev(bs, cluster_sector_num, cluster_nb_sectors, 78861007b31SStefan Hajnoczi &bounce_qiov); 78961007b31SStefan Hajnoczi } 79061007b31SStefan Hajnoczi 79161007b31SStefan Hajnoczi if (ret < 0) { 79261007b31SStefan Hajnoczi /* It might be okay to ignore write errors for guest requests. If this 79361007b31SStefan Hajnoczi * is a deliberate copy-on-read then we don't want to ignore the error. 79461007b31SStefan Hajnoczi * Simply report it in all cases. 79561007b31SStefan Hajnoczi */ 79661007b31SStefan Hajnoczi goto err; 79761007b31SStefan Hajnoczi } 79861007b31SStefan Hajnoczi 79961007b31SStefan Hajnoczi skip_bytes = (sector_num - cluster_sector_num) * BDRV_SECTOR_SIZE; 80061007b31SStefan Hajnoczi qemu_iovec_from_buf(qiov, 0, bounce_buffer + skip_bytes, 80161007b31SStefan Hajnoczi nb_sectors * BDRV_SECTOR_SIZE); 80261007b31SStefan Hajnoczi 80361007b31SStefan Hajnoczi err: 80461007b31SStefan Hajnoczi qemu_vfree(bounce_buffer); 80561007b31SStefan Hajnoczi return ret; 80661007b31SStefan Hajnoczi } 80761007b31SStefan Hajnoczi 80861007b31SStefan Hajnoczi /* 80961007b31SStefan Hajnoczi * Forwards an already correctly aligned request to the BlockDriver. This 81061007b31SStefan Hajnoczi * handles copy on read and zeroing after EOF; any other features must be 81161007b31SStefan Hajnoczi * implemented by the caller. 81261007b31SStefan Hajnoczi */ 81361007b31SStefan Hajnoczi static int coroutine_fn bdrv_aligned_preadv(BlockDriverState *bs, 81461007b31SStefan Hajnoczi BdrvTrackedRequest *req, int64_t offset, unsigned int bytes, 81561007b31SStefan Hajnoczi int64_t align, QEMUIOVector *qiov, int flags) 81661007b31SStefan Hajnoczi { 81761007b31SStefan Hajnoczi BlockDriver *drv = bs->drv; 81861007b31SStefan Hajnoczi int ret; 81961007b31SStefan Hajnoczi 82061007b31SStefan Hajnoczi int64_t sector_num = offset >> BDRV_SECTOR_BITS; 82161007b31SStefan Hajnoczi unsigned int nb_sectors = bytes >> BDRV_SECTOR_BITS; 82261007b31SStefan Hajnoczi 82361007b31SStefan Hajnoczi assert((offset & (BDRV_SECTOR_SIZE - 1)) == 0); 82461007b31SStefan Hajnoczi assert((bytes & (BDRV_SECTOR_SIZE - 1)) == 0); 82561007b31SStefan Hajnoczi assert(!qiov || bytes == qiov->size); 82661007b31SStefan Hajnoczi 82761007b31SStefan Hajnoczi /* Handle Copy on Read and associated serialisation */ 82861007b31SStefan Hajnoczi if (flags & BDRV_REQ_COPY_ON_READ) { 82961007b31SStefan Hajnoczi /* If we touch the same cluster it counts as an overlap. This 83061007b31SStefan Hajnoczi * guarantees that allocating writes will be serialized and not race 83161007b31SStefan Hajnoczi * with each other for the same cluster. For example, in copy-on-read 83261007b31SStefan Hajnoczi * it ensures that the CoR read and write operations are atomic and 83361007b31SStefan Hajnoczi * guest writes cannot interleave between them. */ 83461007b31SStefan Hajnoczi mark_request_serialising(req, bdrv_get_cluster_size(bs)); 83561007b31SStefan Hajnoczi } 83661007b31SStefan Hajnoczi 83761007b31SStefan Hajnoczi wait_serialising_requests(req); 83861007b31SStefan Hajnoczi 83961007b31SStefan Hajnoczi if (flags & BDRV_REQ_COPY_ON_READ) { 84061007b31SStefan Hajnoczi int pnum; 84161007b31SStefan Hajnoczi 84261007b31SStefan Hajnoczi ret = bdrv_is_allocated(bs, sector_num, nb_sectors, &pnum); 84361007b31SStefan Hajnoczi if (ret < 0) { 84461007b31SStefan Hajnoczi goto out; 84561007b31SStefan Hajnoczi } 84661007b31SStefan Hajnoczi 84761007b31SStefan Hajnoczi if (!ret || pnum != nb_sectors) { 84861007b31SStefan Hajnoczi ret = bdrv_co_do_copy_on_readv(bs, sector_num, nb_sectors, qiov); 84961007b31SStefan Hajnoczi goto out; 85061007b31SStefan Hajnoczi } 85161007b31SStefan Hajnoczi } 85261007b31SStefan Hajnoczi 85361007b31SStefan Hajnoczi /* Forward the request to the BlockDriver */ 85461007b31SStefan Hajnoczi if (!bs->zero_beyond_eof) { 85561007b31SStefan Hajnoczi ret = drv->bdrv_co_readv(bs, sector_num, nb_sectors, qiov); 85661007b31SStefan Hajnoczi } else { 85761007b31SStefan Hajnoczi /* Read zeros after EOF */ 85861007b31SStefan Hajnoczi int64_t total_sectors, max_nb_sectors; 85961007b31SStefan Hajnoczi 86061007b31SStefan Hajnoczi total_sectors = bdrv_nb_sectors(bs); 86161007b31SStefan Hajnoczi if (total_sectors < 0) { 86261007b31SStefan Hajnoczi ret = total_sectors; 86361007b31SStefan Hajnoczi goto out; 86461007b31SStefan Hajnoczi } 86561007b31SStefan Hajnoczi 86661007b31SStefan Hajnoczi max_nb_sectors = ROUND_UP(MAX(0, total_sectors - sector_num), 86761007b31SStefan Hajnoczi align >> BDRV_SECTOR_BITS); 86861007b31SStefan Hajnoczi if (nb_sectors < max_nb_sectors) { 86961007b31SStefan Hajnoczi ret = drv->bdrv_co_readv(bs, sector_num, nb_sectors, qiov); 87061007b31SStefan Hajnoczi } else if (max_nb_sectors > 0) { 87161007b31SStefan Hajnoczi QEMUIOVector local_qiov; 87261007b31SStefan Hajnoczi 87361007b31SStefan Hajnoczi qemu_iovec_init(&local_qiov, qiov->niov); 87461007b31SStefan Hajnoczi qemu_iovec_concat(&local_qiov, qiov, 0, 87561007b31SStefan Hajnoczi max_nb_sectors * BDRV_SECTOR_SIZE); 87661007b31SStefan Hajnoczi 87761007b31SStefan Hajnoczi ret = drv->bdrv_co_readv(bs, sector_num, max_nb_sectors, 87861007b31SStefan Hajnoczi &local_qiov); 87961007b31SStefan Hajnoczi 88061007b31SStefan Hajnoczi qemu_iovec_destroy(&local_qiov); 88161007b31SStefan Hajnoczi } else { 88261007b31SStefan Hajnoczi ret = 0; 88361007b31SStefan Hajnoczi } 88461007b31SStefan Hajnoczi 88561007b31SStefan Hajnoczi /* Reading beyond end of file is supposed to produce zeroes */ 88661007b31SStefan Hajnoczi if (ret == 0 && total_sectors < sector_num + nb_sectors) { 88761007b31SStefan Hajnoczi uint64_t offset = MAX(0, total_sectors - sector_num); 88861007b31SStefan Hajnoczi uint64_t bytes = (sector_num + nb_sectors - offset) * 88961007b31SStefan Hajnoczi BDRV_SECTOR_SIZE; 89061007b31SStefan Hajnoczi qemu_iovec_memset(qiov, offset * BDRV_SECTOR_SIZE, 0, bytes); 89161007b31SStefan Hajnoczi } 89261007b31SStefan Hajnoczi } 89361007b31SStefan Hajnoczi 89461007b31SStefan Hajnoczi out: 89561007b31SStefan Hajnoczi return ret; 89661007b31SStefan Hajnoczi } 89761007b31SStefan Hajnoczi 89861007b31SStefan Hajnoczi /* 89961007b31SStefan Hajnoczi * Handle a read request in coroutine context 90061007b31SStefan Hajnoczi */ 90161007b31SStefan Hajnoczi static int coroutine_fn bdrv_co_do_preadv(BlockDriverState *bs, 90261007b31SStefan Hajnoczi int64_t offset, unsigned int bytes, QEMUIOVector *qiov, 90361007b31SStefan Hajnoczi BdrvRequestFlags flags) 90461007b31SStefan Hajnoczi { 90561007b31SStefan Hajnoczi BlockDriver *drv = bs->drv; 90661007b31SStefan Hajnoczi BdrvTrackedRequest req; 90761007b31SStefan Hajnoczi 908d01c07f2SFam Zheng /* TODO Lift BDRV_SECTOR_SIZE restriction in BlockDriver interface */ 909d01c07f2SFam Zheng uint64_t align = MAX(BDRV_SECTOR_SIZE, bs->request_alignment); 91061007b31SStefan Hajnoczi uint8_t *head_buf = NULL; 91161007b31SStefan Hajnoczi uint8_t *tail_buf = NULL; 91261007b31SStefan Hajnoczi QEMUIOVector local_qiov; 91361007b31SStefan Hajnoczi bool use_local_qiov = false; 91461007b31SStefan Hajnoczi int ret; 91561007b31SStefan Hajnoczi 91661007b31SStefan Hajnoczi if (!drv) { 91761007b31SStefan Hajnoczi return -ENOMEDIUM; 91861007b31SStefan Hajnoczi } 91961007b31SStefan Hajnoczi 92061007b31SStefan Hajnoczi ret = bdrv_check_byte_request(bs, offset, bytes); 92161007b31SStefan Hajnoczi if (ret < 0) { 92261007b31SStefan Hajnoczi return ret; 92361007b31SStefan Hajnoczi } 92461007b31SStefan Hajnoczi 92561007b31SStefan Hajnoczi if (bs->copy_on_read) { 92661007b31SStefan Hajnoczi flags |= BDRV_REQ_COPY_ON_READ; 92761007b31SStefan Hajnoczi } 92861007b31SStefan Hajnoczi 92961007b31SStefan Hajnoczi /* throttling disk I/O */ 93061007b31SStefan Hajnoczi if (bs->io_limits_enabled) { 931*76f4afb4SAlberto Garcia throttle_group_co_io_limits_intercept(bs, bytes, false); 93261007b31SStefan Hajnoczi } 93361007b31SStefan Hajnoczi 93461007b31SStefan Hajnoczi /* Align read if necessary by padding qiov */ 93561007b31SStefan Hajnoczi if (offset & (align - 1)) { 93661007b31SStefan Hajnoczi head_buf = qemu_blockalign(bs, align); 93761007b31SStefan Hajnoczi qemu_iovec_init(&local_qiov, qiov->niov + 2); 93861007b31SStefan Hajnoczi qemu_iovec_add(&local_qiov, head_buf, offset & (align - 1)); 93961007b31SStefan Hajnoczi qemu_iovec_concat(&local_qiov, qiov, 0, qiov->size); 94061007b31SStefan Hajnoczi use_local_qiov = true; 94161007b31SStefan Hajnoczi 94261007b31SStefan Hajnoczi bytes += offset & (align - 1); 94361007b31SStefan Hajnoczi offset = offset & ~(align - 1); 94461007b31SStefan Hajnoczi } 94561007b31SStefan Hajnoczi 94661007b31SStefan Hajnoczi if ((offset + bytes) & (align - 1)) { 94761007b31SStefan Hajnoczi if (!use_local_qiov) { 94861007b31SStefan Hajnoczi qemu_iovec_init(&local_qiov, qiov->niov + 1); 94961007b31SStefan Hajnoczi qemu_iovec_concat(&local_qiov, qiov, 0, qiov->size); 95061007b31SStefan Hajnoczi use_local_qiov = true; 95161007b31SStefan Hajnoczi } 95261007b31SStefan Hajnoczi tail_buf = qemu_blockalign(bs, align); 95361007b31SStefan Hajnoczi qemu_iovec_add(&local_qiov, tail_buf, 95461007b31SStefan Hajnoczi align - ((offset + bytes) & (align - 1))); 95561007b31SStefan Hajnoczi 95661007b31SStefan Hajnoczi bytes = ROUND_UP(bytes, align); 95761007b31SStefan Hajnoczi } 95861007b31SStefan Hajnoczi 95961007b31SStefan Hajnoczi tracked_request_begin(&req, bs, offset, bytes, false); 96061007b31SStefan Hajnoczi ret = bdrv_aligned_preadv(bs, &req, offset, bytes, align, 96161007b31SStefan Hajnoczi use_local_qiov ? &local_qiov : qiov, 96261007b31SStefan Hajnoczi flags); 96361007b31SStefan Hajnoczi tracked_request_end(&req); 96461007b31SStefan Hajnoczi 96561007b31SStefan Hajnoczi if (use_local_qiov) { 96661007b31SStefan Hajnoczi qemu_iovec_destroy(&local_qiov); 96761007b31SStefan Hajnoczi qemu_vfree(head_buf); 96861007b31SStefan Hajnoczi qemu_vfree(tail_buf); 96961007b31SStefan Hajnoczi } 97061007b31SStefan Hajnoczi 97161007b31SStefan Hajnoczi return ret; 97261007b31SStefan Hajnoczi } 97361007b31SStefan Hajnoczi 97461007b31SStefan Hajnoczi static int coroutine_fn bdrv_co_do_readv(BlockDriverState *bs, 97561007b31SStefan Hajnoczi int64_t sector_num, int nb_sectors, QEMUIOVector *qiov, 97661007b31SStefan Hajnoczi BdrvRequestFlags flags) 97761007b31SStefan Hajnoczi { 97861007b31SStefan Hajnoczi if (nb_sectors < 0 || nb_sectors > BDRV_REQUEST_MAX_SECTORS) { 97961007b31SStefan Hajnoczi return -EINVAL; 98061007b31SStefan Hajnoczi } 98161007b31SStefan Hajnoczi 98261007b31SStefan Hajnoczi return bdrv_co_do_preadv(bs, sector_num << BDRV_SECTOR_BITS, 98361007b31SStefan Hajnoczi nb_sectors << BDRV_SECTOR_BITS, qiov, flags); 98461007b31SStefan Hajnoczi } 98561007b31SStefan Hajnoczi 98661007b31SStefan Hajnoczi int coroutine_fn bdrv_co_readv(BlockDriverState *bs, int64_t sector_num, 98761007b31SStefan Hajnoczi int nb_sectors, QEMUIOVector *qiov) 98861007b31SStefan Hajnoczi { 98961007b31SStefan Hajnoczi trace_bdrv_co_readv(bs, sector_num, nb_sectors); 99061007b31SStefan Hajnoczi 99161007b31SStefan Hajnoczi return bdrv_co_do_readv(bs, sector_num, nb_sectors, qiov, 0); 99261007b31SStefan Hajnoczi } 99361007b31SStefan Hajnoczi 99461007b31SStefan Hajnoczi int coroutine_fn bdrv_co_copy_on_readv(BlockDriverState *bs, 99561007b31SStefan Hajnoczi int64_t sector_num, int nb_sectors, QEMUIOVector *qiov) 99661007b31SStefan Hajnoczi { 99761007b31SStefan Hajnoczi trace_bdrv_co_copy_on_readv(bs, sector_num, nb_sectors); 99861007b31SStefan Hajnoczi 99961007b31SStefan Hajnoczi return bdrv_co_do_readv(bs, sector_num, nb_sectors, qiov, 100061007b31SStefan Hajnoczi BDRV_REQ_COPY_ON_READ); 100161007b31SStefan Hajnoczi } 100261007b31SStefan Hajnoczi 100361007b31SStefan Hajnoczi #define MAX_WRITE_ZEROES_BOUNCE_BUFFER 32768 100461007b31SStefan Hajnoczi 100561007b31SStefan Hajnoczi static int coroutine_fn bdrv_co_do_write_zeroes(BlockDriverState *bs, 100661007b31SStefan Hajnoczi int64_t sector_num, int nb_sectors, BdrvRequestFlags flags) 100761007b31SStefan Hajnoczi { 100861007b31SStefan Hajnoczi BlockDriver *drv = bs->drv; 100961007b31SStefan Hajnoczi QEMUIOVector qiov; 101061007b31SStefan Hajnoczi struct iovec iov = {0}; 101161007b31SStefan Hajnoczi int ret = 0; 101261007b31SStefan Hajnoczi 101361007b31SStefan Hajnoczi int max_write_zeroes = MIN_NON_ZERO(bs->bl.max_write_zeroes, 101461007b31SStefan Hajnoczi BDRV_REQUEST_MAX_SECTORS); 101561007b31SStefan Hajnoczi 101661007b31SStefan Hajnoczi while (nb_sectors > 0 && !ret) { 101761007b31SStefan Hajnoczi int num = nb_sectors; 101861007b31SStefan Hajnoczi 101961007b31SStefan Hajnoczi /* Align request. Block drivers can expect the "bulk" of the request 102061007b31SStefan Hajnoczi * to be aligned. 102161007b31SStefan Hajnoczi */ 102261007b31SStefan Hajnoczi if (bs->bl.write_zeroes_alignment 102361007b31SStefan Hajnoczi && num > bs->bl.write_zeroes_alignment) { 102461007b31SStefan Hajnoczi if (sector_num % bs->bl.write_zeroes_alignment != 0) { 102561007b31SStefan Hajnoczi /* Make a small request up to the first aligned sector. */ 102661007b31SStefan Hajnoczi num = bs->bl.write_zeroes_alignment; 102761007b31SStefan Hajnoczi num -= sector_num % bs->bl.write_zeroes_alignment; 102861007b31SStefan Hajnoczi } else if ((sector_num + num) % bs->bl.write_zeroes_alignment != 0) { 102961007b31SStefan Hajnoczi /* Shorten the request to the last aligned sector. num cannot 103061007b31SStefan Hajnoczi * underflow because num > bs->bl.write_zeroes_alignment. 103161007b31SStefan Hajnoczi */ 103261007b31SStefan Hajnoczi num -= (sector_num + num) % bs->bl.write_zeroes_alignment; 103361007b31SStefan Hajnoczi } 103461007b31SStefan Hajnoczi } 103561007b31SStefan Hajnoczi 103661007b31SStefan Hajnoczi /* limit request size */ 103761007b31SStefan Hajnoczi if (num > max_write_zeroes) { 103861007b31SStefan Hajnoczi num = max_write_zeroes; 103961007b31SStefan Hajnoczi } 104061007b31SStefan Hajnoczi 104161007b31SStefan Hajnoczi ret = -ENOTSUP; 104261007b31SStefan Hajnoczi /* First try the efficient write zeroes operation */ 104361007b31SStefan Hajnoczi if (drv->bdrv_co_write_zeroes) { 104461007b31SStefan Hajnoczi ret = drv->bdrv_co_write_zeroes(bs, sector_num, num, flags); 104561007b31SStefan Hajnoczi } 104661007b31SStefan Hajnoczi 104761007b31SStefan Hajnoczi if (ret == -ENOTSUP) { 104861007b31SStefan Hajnoczi /* Fall back to bounce buffer if write zeroes is unsupported */ 104961007b31SStefan Hajnoczi int max_xfer_len = MIN_NON_ZERO(bs->bl.max_transfer_length, 105061007b31SStefan Hajnoczi MAX_WRITE_ZEROES_BOUNCE_BUFFER); 105161007b31SStefan Hajnoczi num = MIN(num, max_xfer_len); 105261007b31SStefan Hajnoczi iov.iov_len = num * BDRV_SECTOR_SIZE; 105361007b31SStefan Hajnoczi if (iov.iov_base == NULL) { 105461007b31SStefan Hajnoczi iov.iov_base = qemu_try_blockalign(bs, num * BDRV_SECTOR_SIZE); 105561007b31SStefan Hajnoczi if (iov.iov_base == NULL) { 105661007b31SStefan Hajnoczi ret = -ENOMEM; 105761007b31SStefan Hajnoczi goto fail; 105861007b31SStefan Hajnoczi } 105961007b31SStefan Hajnoczi memset(iov.iov_base, 0, num * BDRV_SECTOR_SIZE); 106061007b31SStefan Hajnoczi } 106161007b31SStefan Hajnoczi qemu_iovec_init_external(&qiov, &iov, 1); 106261007b31SStefan Hajnoczi 106361007b31SStefan Hajnoczi ret = drv->bdrv_co_writev(bs, sector_num, num, &qiov); 106461007b31SStefan Hajnoczi 106561007b31SStefan Hajnoczi /* Keep bounce buffer around if it is big enough for all 106661007b31SStefan Hajnoczi * all future requests. 106761007b31SStefan Hajnoczi */ 106861007b31SStefan Hajnoczi if (num < max_xfer_len) { 106961007b31SStefan Hajnoczi qemu_vfree(iov.iov_base); 107061007b31SStefan Hajnoczi iov.iov_base = NULL; 107161007b31SStefan Hajnoczi } 107261007b31SStefan Hajnoczi } 107361007b31SStefan Hajnoczi 107461007b31SStefan Hajnoczi sector_num += num; 107561007b31SStefan Hajnoczi nb_sectors -= num; 107661007b31SStefan Hajnoczi } 107761007b31SStefan Hajnoczi 107861007b31SStefan Hajnoczi fail: 107961007b31SStefan Hajnoczi qemu_vfree(iov.iov_base); 108061007b31SStefan Hajnoczi return ret; 108161007b31SStefan Hajnoczi } 108261007b31SStefan Hajnoczi 108361007b31SStefan Hajnoczi /* 108461007b31SStefan Hajnoczi * Forwards an already correctly aligned write request to the BlockDriver. 108561007b31SStefan Hajnoczi */ 108661007b31SStefan Hajnoczi static int coroutine_fn bdrv_aligned_pwritev(BlockDriverState *bs, 108761007b31SStefan Hajnoczi BdrvTrackedRequest *req, int64_t offset, unsigned int bytes, 108861007b31SStefan Hajnoczi QEMUIOVector *qiov, int flags) 108961007b31SStefan Hajnoczi { 109061007b31SStefan Hajnoczi BlockDriver *drv = bs->drv; 109161007b31SStefan Hajnoczi bool waited; 109261007b31SStefan Hajnoczi int ret; 109361007b31SStefan Hajnoczi 109461007b31SStefan Hajnoczi int64_t sector_num = offset >> BDRV_SECTOR_BITS; 109561007b31SStefan Hajnoczi unsigned int nb_sectors = bytes >> BDRV_SECTOR_BITS; 109661007b31SStefan Hajnoczi 109761007b31SStefan Hajnoczi assert((offset & (BDRV_SECTOR_SIZE - 1)) == 0); 109861007b31SStefan Hajnoczi assert((bytes & (BDRV_SECTOR_SIZE - 1)) == 0); 109961007b31SStefan Hajnoczi assert(!qiov || bytes == qiov->size); 110061007b31SStefan Hajnoczi 110161007b31SStefan Hajnoczi waited = wait_serialising_requests(req); 110261007b31SStefan Hajnoczi assert(!waited || !req->serialising); 110361007b31SStefan Hajnoczi assert(req->overlap_offset <= offset); 110461007b31SStefan Hajnoczi assert(offset + bytes <= req->overlap_offset + req->overlap_bytes); 110561007b31SStefan Hajnoczi 110661007b31SStefan Hajnoczi ret = notifier_with_return_list_notify(&bs->before_write_notifiers, req); 110761007b31SStefan Hajnoczi 110861007b31SStefan Hajnoczi if (!ret && bs->detect_zeroes != BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF && 110961007b31SStefan Hajnoczi !(flags & BDRV_REQ_ZERO_WRITE) && drv->bdrv_co_write_zeroes && 111061007b31SStefan Hajnoczi qemu_iovec_is_zero(qiov)) { 111161007b31SStefan Hajnoczi flags |= BDRV_REQ_ZERO_WRITE; 111261007b31SStefan Hajnoczi if (bs->detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP) { 111361007b31SStefan Hajnoczi flags |= BDRV_REQ_MAY_UNMAP; 111461007b31SStefan Hajnoczi } 111561007b31SStefan Hajnoczi } 111661007b31SStefan Hajnoczi 111761007b31SStefan Hajnoczi if (ret < 0) { 111861007b31SStefan Hajnoczi /* Do nothing, write notifier decided to fail this request */ 111961007b31SStefan Hajnoczi } else if (flags & BDRV_REQ_ZERO_WRITE) { 112061007b31SStefan Hajnoczi BLKDBG_EVENT(bs, BLKDBG_PWRITEV_ZERO); 112161007b31SStefan Hajnoczi ret = bdrv_co_do_write_zeroes(bs, sector_num, nb_sectors, flags); 112261007b31SStefan Hajnoczi } else { 112361007b31SStefan Hajnoczi BLKDBG_EVENT(bs, BLKDBG_PWRITEV); 112461007b31SStefan Hajnoczi ret = drv->bdrv_co_writev(bs, sector_num, nb_sectors, qiov); 112561007b31SStefan Hajnoczi } 112661007b31SStefan Hajnoczi BLKDBG_EVENT(bs, BLKDBG_PWRITEV_DONE); 112761007b31SStefan Hajnoczi 112861007b31SStefan Hajnoczi if (ret == 0 && !bs->enable_write_cache) { 112961007b31SStefan Hajnoczi ret = bdrv_co_flush(bs); 113061007b31SStefan Hajnoczi } 113161007b31SStefan Hajnoczi 113261007b31SStefan Hajnoczi bdrv_set_dirty(bs, sector_num, nb_sectors); 113361007b31SStefan Hajnoczi 113461007b31SStefan Hajnoczi block_acct_highest_sector(&bs->stats, sector_num, nb_sectors); 113561007b31SStefan Hajnoczi 113661007b31SStefan Hajnoczi if (ret >= 0) { 113761007b31SStefan Hajnoczi bs->total_sectors = MAX(bs->total_sectors, sector_num + nb_sectors); 113861007b31SStefan Hajnoczi } 113961007b31SStefan Hajnoczi 114061007b31SStefan Hajnoczi return ret; 114161007b31SStefan Hajnoczi } 114261007b31SStefan Hajnoczi 11439eeb6dd1SFam Zheng static int coroutine_fn bdrv_co_do_zero_pwritev(BlockDriverState *bs, 11449eeb6dd1SFam Zheng int64_t offset, 11459eeb6dd1SFam Zheng unsigned int bytes, 11469eeb6dd1SFam Zheng BdrvRequestFlags flags, 11479eeb6dd1SFam Zheng BdrvTrackedRequest *req) 11489eeb6dd1SFam Zheng { 11499eeb6dd1SFam Zheng uint8_t *buf = NULL; 11509eeb6dd1SFam Zheng QEMUIOVector local_qiov; 11519eeb6dd1SFam Zheng struct iovec iov; 11529eeb6dd1SFam Zheng uint64_t align = MAX(BDRV_SECTOR_SIZE, bs->request_alignment); 11539eeb6dd1SFam Zheng unsigned int head_padding_bytes, tail_padding_bytes; 11549eeb6dd1SFam Zheng int ret = 0; 11559eeb6dd1SFam Zheng 11569eeb6dd1SFam Zheng head_padding_bytes = offset & (align - 1); 11579eeb6dd1SFam Zheng tail_padding_bytes = align - ((offset + bytes) & (align - 1)); 11589eeb6dd1SFam Zheng 11599eeb6dd1SFam Zheng 11609eeb6dd1SFam Zheng assert(flags & BDRV_REQ_ZERO_WRITE); 11619eeb6dd1SFam Zheng if (head_padding_bytes || tail_padding_bytes) { 11629eeb6dd1SFam Zheng buf = qemu_blockalign(bs, align); 11639eeb6dd1SFam Zheng iov = (struct iovec) { 11649eeb6dd1SFam Zheng .iov_base = buf, 11659eeb6dd1SFam Zheng .iov_len = align, 11669eeb6dd1SFam Zheng }; 11679eeb6dd1SFam Zheng qemu_iovec_init_external(&local_qiov, &iov, 1); 11689eeb6dd1SFam Zheng } 11699eeb6dd1SFam Zheng if (head_padding_bytes) { 11709eeb6dd1SFam Zheng uint64_t zero_bytes = MIN(bytes, align - head_padding_bytes); 11719eeb6dd1SFam Zheng 11729eeb6dd1SFam Zheng /* RMW the unaligned part before head. */ 11739eeb6dd1SFam Zheng mark_request_serialising(req, align); 11749eeb6dd1SFam Zheng wait_serialising_requests(req); 11759eeb6dd1SFam Zheng BLKDBG_EVENT(bs, BLKDBG_PWRITEV_RMW_HEAD); 11769eeb6dd1SFam Zheng ret = bdrv_aligned_preadv(bs, req, offset & ~(align - 1), align, 11779eeb6dd1SFam Zheng align, &local_qiov, 0); 11789eeb6dd1SFam Zheng if (ret < 0) { 11799eeb6dd1SFam Zheng goto fail; 11809eeb6dd1SFam Zheng } 11819eeb6dd1SFam Zheng BLKDBG_EVENT(bs, BLKDBG_PWRITEV_RMW_AFTER_HEAD); 11829eeb6dd1SFam Zheng 11839eeb6dd1SFam Zheng memset(buf + head_padding_bytes, 0, zero_bytes); 11849eeb6dd1SFam Zheng ret = bdrv_aligned_pwritev(bs, req, offset & ~(align - 1), align, 11859eeb6dd1SFam Zheng &local_qiov, 11869eeb6dd1SFam Zheng flags & ~BDRV_REQ_ZERO_WRITE); 11879eeb6dd1SFam Zheng if (ret < 0) { 11889eeb6dd1SFam Zheng goto fail; 11899eeb6dd1SFam Zheng } 11909eeb6dd1SFam Zheng offset += zero_bytes; 11919eeb6dd1SFam Zheng bytes -= zero_bytes; 11929eeb6dd1SFam Zheng } 11939eeb6dd1SFam Zheng 11949eeb6dd1SFam Zheng assert(!bytes || (offset & (align - 1)) == 0); 11959eeb6dd1SFam Zheng if (bytes >= align) { 11969eeb6dd1SFam Zheng /* Write the aligned part in the middle. */ 11979eeb6dd1SFam Zheng uint64_t aligned_bytes = bytes & ~(align - 1); 11989eeb6dd1SFam Zheng ret = bdrv_aligned_pwritev(bs, req, offset, aligned_bytes, 11999eeb6dd1SFam Zheng NULL, flags); 12009eeb6dd1SFam Zheng if (ret < 0) { 12019eeb6dd1SFam Zheng goto fail; 12029eeb6dd1SFam Zheng } 12039eeb6dd1SFam Zheng bytes -= aligned_bytes; 12049eeb6dd1SFam Zheng offset += aligned_bytes; 12059eeb6dd1SFam Zheng } 12069eeb6dd1SFam Zheng 12079eeb6dd1SFam Zheng assert(!bytes || (offset & (align - 1)) == 0); 12089eeb6dd1SFam Zheng if (bytes) { 12099eeb6dd1SFam Zheng assert(align == tail_padding_bytes + bytes); 12109eeb6dd1SFam Zheng /* RMW the unaligned part after tail. */ 12119eeb6dd1SFam Zheng mark_request_serialising(req, align); 12129eeb6dd1SFam Zheng wait_serialising_requests(req); 12139eeb6dd1SFam Zheng BLKDBG_EVENT(bs, BLKDBG_PWRITEV_RMW_TAIL); 12149eeb6dd1SFam Zheng ret = bdrv_aligned_preadv(bs, req, offset, align, 12159eeb6dd1SFam Zheng align, &local_qiov, 0); 12169eeb6dd1SFam Zheng if (ret < 0) { 12179eeb6dd1SFam Zheng goto fail; 12189eeb6dd1SFam Zheng } 12199eeb6dd1SFam Zheng BLKDBG_EVENT(bs, BLKDBG_PWRITEV_RMW_AFTER_TAIL); 12209eeb6dd1SFam Zheng 12219eeb6dd1SFam Zheng memset(buf, 0, bytes); 12229eeb6dd1SFam Zheng ret = bdrv_aligned_pwritev(bs, req, offset, align, 12239eeb6dd1SFam Zheng &local_qiov, flags & ~BDRV_REQ_ZERO_WRITE); 12249eeb6dd1SFam Zheng } 12259eeb6dd1SFam Zheng fail: 12269eeb6dd1SFam Zheng qemu_vfree(buf); 12279eeb6dd1SFam Zheng return ret; 12289eeb6dd1SFam Zheng 12299eeb6dd1SFam Zheng } 12309eeb6dd1SFam Zheng 123161007b31SStefan Hajnoczi /* 123261007b31SStefan Hajnoczi * Handle a write request in coroutine context 123361007b31SStefan Hajnoczi */ 123461007b31SStefan Hajnoczi static int coroutine_fn bdrv_co_do_pwritev(BlockDriverState *bs, 123561007b31SStefan Hajnoczi int64_t offset, unsigned int bytes, QEMUIOVector *qiov, 123661007b31SStefan Hajnoczi BdrvRequestFlags flags) 123761007b31SStefan Hajnoczi { 123861007b31SStefan Hajnoczi BdrvTrackedRequest req; 1239d01c07f2SFam Zheng /* TODO Lift BDRV_SECTOR_SIZE restriction in BlockDriver interface */ 1240d01c07f2SFam Zheng uint64_t align = MAX(BDRV_SECTOR_SIZE, bs->request_alignment); 124161007b31SStefan Hajnoczi uint8_t *head_buf = NULL; 124261007b31SStefan Hajnoczi uint8_t *tail_buf = NULL; 124361007b31SStefan Hajnoczi QEMUIOVector local_qiov; 124461007b31SStefan Hajnoczi bool use_local_qiov = false; 124561007b31SStefan Hajnoczi int ret; 124661007b31SStefan Hajnoczi 124761007b31SStefan Hajnoczi if (!bs->drv) { 124861007b31SStefan Hajnoczi return -ENOMEDIUM; 124961007b31SStefan Hajnoczi } 125061007b31SStefan Hajnoczi if (bs->read_only) { 1251eaf5fe2dSPaolo Bonzini return -EPERM; 125261007b31SStefan Hajnoczi } 125361007b31SStefan Hajnoczi 125461007b31SStefan Hajnoczi ret = bdrv_check_byte_request(bs, offset, bytes); 125561007b31SStefan Hajnoczi if (ret < 0) { 125661007b31SStefan Hajnoczi return ret; 125761007b31SStefan Hajnoczi } 125861007b31SStefan Hajnoczi 125961007b31SStefan Hajnoczi /* throttling disk I/O */ 126061007b31SStefan Hajnoczi if (bs->io_limits_enabled) { 1261*76f4afb4SAlberto Garcia throttle_group_co_io_limits_intercept(bs, bytes, true); 126261007b31SStefan Hajnoczi } 126361007b31SStefan Hajnoczi 126461007b31SStefan Hajnoczi /* 126561007b31SStefan Hajnoczi * Align write if necessary by performing a read-modify-write cycle. 126661007b31SStefan Hajnoczi * Pad qiov with the read parts and be sure to have a tracked request not 126761007b31SStefan Hajnoczi * only for bdrv_aligned_pwritev, but also for the reads of the RMW cycle. 126861007b31SStefan Hajnoczi */ 126961007b31SStefan Hajnoczi tracked_request_begin(&req, bs, offset, bytes, true); 127061007b31SStefan Hajnoczi 12719eeb6dd1SFam Zheng if (!qiov) { 12729eeb6dd1SFam Zheng ret = bdrv_co_do_zero_pwritev(bs, offset, bytes, flags, &req); 12739eeb6dd1SFam Zheng goto out; 12749eeb6dd1SFam Zheng } 12759eeb6dd1SFam Zheng 127661007b31SStefan Hajnoczi if (offset & (align - 1)) { 127761007b31SStefan Hajnoczi QEMUIOVector head_qiov; 127861007b31SStefan Hajnoczi struct iovec head_iov; 127961007b31SStefan Hajnoczi 128061007b31SStefan Hajnoczi mark_request_serialising(&req, align); 128161007b31SStefan Hajnoczi wait_serialising_requests(&req); 128261007b31SStefan Hajnoczi 128361007b31SStefan Hajnoczi head_buf = qemu_blockalign(bs, align); 128461007b31SStefan Hajnoczi head_iov = (struct iovec) { 128561007b31SStefan Hajnoczi .iov_base = head_buf, 128661007b31SStefan Hajnoczi .iov_len = align, 128761007b31SStefan Hajnoczi }; 128861007b31SStefan Hajnoczi qemu_iovec_init_external(&head_qiov, &head_iov, 1); 128961007b31SStefan Hajnoczi 129061007b31SStefan Hajnoczi BLKDBG_EVENT(bs, BLKDBG_PWRITEV_RMW_HEAD); 129161007b31SStefan Hajnoczi ret = bdrv_aligned_preadv(bs, &req, offset & ~(align - 1), align, 129261007b31SStefan Hajnoczi align, &head_qiov, 0); 129361007b31SStefan Hajnoczi if (ret < 0) { 129461007b31SStefan Hajnoczi goto fail; 129561007b31SStefan Hajnoczi } 129661007b31SStefan Hajnoczi BLKDBG_EVENT(bs, BLKDBG_PWRITEV_RMW_AFTER_HEAD); 129761007b31SStefan Hajnoczi 129861007b31SStefan Hajnoczi qemu_iovec_init(&local_qiov, qiov->niov + 2); 129961007b31SStefan Hajnoczi qemu_iovec_add(&local_qiov, head_buf, offset & (align - 1)); 130061007b31SStefan Hajnoczi qemu_iovec_concat(&local_qiov, qiov, 0, qiov->size); 130161007b31SStefan Hajnoczi use_local_qiov = true; 130261007b31SStefan Hajnoczi 130361007b31SStefan Hajnoczi bytes += offset & (align - 1); 130461007b31SStefan Hajnoczi offset = offset & ~(align - 1); 130561007b31SStefan Hajnoczi } 130661007b31SStefan Hajnoczi 130761007b31SStefan Hajnoczi if ((offset + bytes) & (align - 1)) { 130861007b31SStefan Hajnoczi QEMUIOVector tail_qiov; 130961007b31SStefan Hajnoczi struct iovec tail_iov; 131061007b31SStefan Hajnoczi size_t tail_bytes; 131161007b31SStefan Hajnoczi bool waited; 131261007b31SStefan Hajnoczi 131361007b31SStefan Hajnoczi mark_request_serialising(&req, align); 131461007b31SStefan Hajnoczi waited = wait_serialising_requests(&req); 131561007b31SStefan Hajnoczi assert(!waited || !use_local_qiov); 131661007b31SStefan Hajnoczi 131761007b31SStefan Hajnoczi tail_buf = qemu_blockalign(bs, align); 131861007b31SStefan Hajnoczi tail_iov = (struct iovec) { 131961007b31SStefan Hajnoczi .iov_base = tail_buf, 132061007b31SStefan Hajnoczi .iov_len = align, 132161007b31SStefan Hajnoczi }; 132261007b31SStefan Hajnoczi qemu_iovec_init_external(&tail_qiov, &tail_iov, 1); 132361007b31SStefan Hajnoczi 132461007b31SStefan Hajnoczi BLKDBG_EVENT(bs, BLKDBG_PWRITEV_RMW_TAIL); 132561007b31SStefan Hajnoczi ret = bdrv_aligned_preadv(bs, &req, (offset + bytes) & ~(align - 1), align, 132661007b31SStefan Hajnoczi align, &tail_qiov, 0); 132761007b31SStefan Hajnoczi if (ret < 0) { 132861007b31SStefan Hajnoczi goto fail; 132961007b31SStefan Hajnoczi } 133061007b31SStefan Hajnoczi BLKDBG_EVENT(bs, BLKDBG_PWRITEV_RMW_AFTER_TAIL); 133161007b31SStefan Hajnoczi 133261007b31SStefan Hajnoczi if (!use_local_qiov) { 133361007b31SStefan Hajnoczi qemu_iovec_init(&local_qiov, qiov->niov + 1); 133461007b31SStefan Hajnoczi qemu_iovec_concat(&local_qiov, qiov, 0, qiov->size); 133561007b31SStefan Hajnoczi use_local_qiov = true; 133661007b31SStefan Hajnoczi } 133761007b31SStefan Hajnoczi 133861007b31SStefan Hajnoczi tail_bytes = (offset + bytes) & (align - 1); 133961007b31SStefan Hajnoczi qemu_iovec_add(&local_qiov, tail_buf + tail_bytes, align - tail_bytes); 134061007b31SStefan Hajnoczi 134161007b31SStefan Hajnoczi bytes = ROUND_UP(bytes, align); 134261007b31SStefan Hajnoczi } 134361007b31SStefan Hajnoczi 134461007b31SStefan Hajnoczi ret = bdrv_aligned_pwritev(bs, &req, offset, bytes, 134561007b31SStefan Hajnoczi use_local_qiov ? &local_qiov : qiov, 134661007b31SStefan Hajnoczi flags); 134761007b31SStefan Hajnoczi 134861007b31SStefan Hajnoczi fail: 134961007b31SStefan Hajnoczi 135061007b31SStefan Hajnoczi if (use_local_qiov) { 135161007b31SStefan Hajnoczi qemu_iovec_destroy(&local_qiov); 135261007b31SStefan Hajnoczi } 135361007b31SStefan Hajnoczi qemu_vfree(head_buf); 135461007b31SStefan Hajnoczi qemu_vfree(tail_buf); 13559eeb6dd1SFam Zheng out: 13569eeb6dd1SFam Zheng tracked_request_end(&req); 135761007b31SStefan Hajnoczi return ret; 135861007b31SStefan Hajnoczi } 135961007b31SStefan Hajnoczi 136061007b31SStefan Hajnoczi static int coroutine_fn bdrv_co_do_writev(BlockDriverState *bs, 136161007b31SStefan Hajnoczi int64_t sector_num, int nb_sectors, QEMUIOVector *qiov, 136261007b31SStefan Hajnoczi BdrvRequestFlags flags) 136361007b31SStefan Hajnoczi { 136461007b31SStefan Hajnoczi if (nb_sectors < 0 || nb_sectors > BDRV_REQUEST_MAX_SECTORS) { 136561007b31SStefan Hajnoczi return -EINVAL; 136661007b31SStefan Hajnoczi } 136761007b31SStefan Hajnoczi 136861007b31SStefan Hajnoczi return bdrv_co_do_pwritev(bs, sector_num << BDRV_SECTOR_BITS, 136961007b31SStefan Hajnoczi nb_sectors << BDRV_SECTOR_BITS, qiov, flags); 137061007b31SStefan Hajnoczi } 137161007b31SStefan Hajnoczi 137261007b31SStefan Hajnoczi int coroutine_fn bdrv_co_writev(BlockDriverState *bs, int64_t sector_num, 137361007b31SStefan Hajnoczi int nb_sectors, QEMUIOVector *qiov) 137461007b31SStefan Hajnoczi { 137561007b31SStefan Hajnoczi trace_bdrv_co_writev(bs, sector_num, nb_sectors); 137661007b31SStefan Hajnoczi 137761007b31SStefan Hajnoczi return bdrv_co_do_writev(bs, sector_num, nb_sectors, qiov, 0); 137861007b31SStefan Hajnoczi } 137961007b31SStefan Hajnoczi 138061007b31SStefan Hajnoczi int coroutine_fn bdrv_co_write_zeroes(BlockDriverState *bs, 138161007b31SStefan Hajnoczi int64_t sector_num, int nb_sectors, 138261007b31SStefan Hajnoczi BdrvRequestFlags flags) 138361007b31SStefan Hajnoczi { 138461007b31SStefan Hajnoczi trace_bdrv_co_write_zeroes(bs, sector_num, nb_sectors, flags); 138561007b31SStefan Hajnoczi 138661007b31SStefan Hajnoczi if (!(bs->open_flags & BDRV_O_UNMAP)) { 138761007b31SStefan Hajnoczi flags &= ~BDRV_REQ_MAY_UNMAP; 138861007b31SStefan Hajnoczi } 138961007b31SStefan Hajnoczi 1390d01c07f2SFam Zheng return bdrv_co_do_writev(bs, sector_num, nb_sectors, NULL, 139161007b31SStefan Hajnoczi BDRV_REQ_ZERO_WRITE | flags); 139261007b31SStefan Hajnoczi } 139361007b31SStefan Hajnoczi 139461007b31SStefan Hajnoczi int bdrv_flush_all(void) 139561007b31SStefan Hajnoczi { 139661007b31SStefan Hajnoczi BlockDriverState *bs = NULL; 139761007b31SStefan Hajnoczi int result = 0; 139861007b31SStefan Hajnoczi 139961007b31SStefan Hajnoczi while ((bs = bdrv_next(bs))) { 140061007b31SStefan Hajnoczi AioContext *aio_context = bdrv_get_aio_context(bs); 140161007b31SStefan Hajnoczi int ret; 140261007b31SStefan Hajnoczi 140361007b31SStefan Hajnoczi aio_context_acquire(aio_context); 140461007b31SStefan Hajnoczi ret = bdrv_flush(bs); 140561007b31SStefan Hajnoczi if (ret < 0 && !result) { 140661007b31SStefan Hajnoczi result = ret; 140761007b31SStefan Hajnoczi } 140861007b31SStefan Hajnoczi aio_context_release(aio_context); 140961007b31SStefan Hajnoczi } 141061007b31SStefan Hajnoczi 141161007b31SStefan Hajnoczi return result; 141261007b31SStefan Hajnoczi } 141361007b31SStefan Hajnoczi 141461007b31SStefan Hajnoczi typedef struct BdrvCoGetBlockStatusData { 141561007b31SStefan Hajnoczi BlockDriverState *bs; 141661007b31SStefan Hajnoczi BlockDriverState *base; 141761007b31SStefan Hajnoczi int64_t sector_num; 141861007b31SStefan Hajnoczi int nb_sectors; 141961007b31SStefan Hajnoczi int *pnum; 142061007b31SStefan Hajnoczi int64_t ret; 142161007b31SStefan Hajnoczi bool done; 142261007b31SStefan Hajnoczi } BdrvCoGetBlockStatusData; 142361007b31SStefan Hajnoczi 142461007b31SStefan Hajnoczi /* 142561007b31SStefan Hajnoczi * Returns the allocation status of the specified sectors. 142661007b31SStefan Hajnoczi * Drivers not implementing the functionality are assumed to not support 142761007b31SStefan Hajnoczi * backing files, hence all their sectors are reported as allocated. 142861007b31SStefan Hajnoczi * 142961007b31SStefan Hajnoczi * If 'sector_num' is beyond the end of the disk image the return value is 0 143061007b31SStefan Hajnoczi * and 'pnum' is set to 0. 143161007b31SStefan Hajnoczi * 143261007b31SStefan Hajnoczi * 'pnum' is set to the number of sectors (including and immediately following 143361007b31SStefan Hajnoczi * the specified sector) that are known to be in the same 143461007b31SStefan Hajnoczi * allocated/unallocated state. 143561007b31SStefan Hajnoczi * 143661007b31SStefan Hajnoczi * 'nb_sectors' is the max value 'pnum' should be set to. If nb_sectors goes 143761007b31SStefan Hajnoczi * beyond the end of the disk image it will be clamped. 143861007b31SStefan Hajnoczi */ 143961007b31SStefan Hajnoczi static int64_t coroutine_fn bdrv_co_get_block_status(BlockDriverState *bs, 144061007b31SStefan Hajnoczi int64_t sector_num, 144161007b31SStefan Hajnoczi int nb_sectors, int *pnum) 144261007b31SStefan Hajnoczi { 144361007b31SStefan Hajnoczi int64_t total_sectors; 144461007b31SStefan Hajnoczi int64_t n; 144561007b31SStefan Hajnoczi int64_t ret, ret2; 144661007b31SStefan Hajnoczi 144761007b31SStefan Hajnoczi total_sectors = bdrv_nb_sectors(bs); 144861007b31SStefan Hajnoczi if (total_sectors < 0) { 144961007b31SStefan Hajnoczi return total_sectors; 145061007b31SStefan Hajnoczi } 145161007b31SStefan Hajnoczi 145261007b31SStefan Hajnoczi if (sector_num >= total_sectors) { 145361007b31SStefan Hajnoczi *pnum = 0; 145461007b31SStefan Hajnoczi return 0; 145561007b31SStefan Hajnoczi } 145661007b31SStefan Hajnoczi 145761007b31SStefan Hajnoczi n = total_sectors - sector_num; 145861007b31SStefan Hajnoczi if (n < nb_sectors) { 145961007b31SStefan Hajnoczi nb_sectors = n; 146061007b31SStefan Hajnoczi } 146161007b31SStefan Hajnoczi 146261007b31SStefan Hajnoczi if (!bs->drv->bdrv_co_get_block_status) { 146361007b31SStefan Hajnoczi *pnum = nb_sectors; 146461007b31SStefan Hajnoczi ret = BDRV_BLOCK_DATA | BDRV_BLOCK_ALLOCATED; 146561007b31SStefan Hajnoczi if (bs->drv->protocol_name) { 146661007b31SStefan Hajnoczi ret |= BDRV_BLOCK_OFFSET_VALID | (sector_num * BDRV_SECTOR_SIZE); 146761007b31SStefan Hajnoczi } 146861007b31SStefan Hajnoczi return ret; 146961007b31SStefan Hajnoczi } 147061007b31SStefan Hajnoczi 147161007b31SStefan Hajnoczi ret = bs->drv->bdrv_co_get_block_status(bs, sector_num, nb_sectors, pnum); 147261007b31SStefan Hajnoczi if (ret < 0) { 147361007b31SStefan Hajnoczi *pnum = 0; 147461007b31SStefan Hajnoczi return ret; 147561007b31SStefan Hajnoczi } 147661007b31SStefan Hajnoczi 147761007b31SStefan Hajnoczi if (ret & BDRV_BLOCK_RAW) { 147861007b31SStefan Hajnoczi assert(ret & BDRV_BLOCK_OFFSET_VALID); 147961007b31SStefan Hajnoczi return bdrv_get_block_status(bs->file, ret >> BDRV_SECTOR_BITS, 148061007b31SStefan Hajnoczi *pnum, pnum); 148161007b31SStefan Hajnoczi } 148261007b31SStefan Hajnoczi 148361007b31SStefan Hajnoczi if (ret & (BDRV_BLOCK_DATA | BDRV_BLOCK_ZERO)) { 148461007b31SStefan Hajnoczi ret |= BDRV_BLOCK_ALLOCATED; 1485a53f1a95SPaolo Bonzini } else { 148661007b31SStefan Hajnoczi if (bdrv_unallocated_blocks_are_zero(bs)) { 148761007b31SStefan Hajnoczi ret |= BDRV_BLOCK_ZERO; 148861007b31SStefan Hajnoczi } else if (bs->backing_hd) { 148961007b31SStefan Hajnoczi BlockDriverState *bs2 = bs->backing_hd; 149061007b31SStefan Hajnoczi int64_t nb_sectors2 = bdrv_nb_sectors(bs2); 149161007b31SStefan Hajnoczi if (nb_sectors2 >= 0 && sector_num >= nb_sectors2) { 149261007b31SStefan Hajnoczi ret |= BDRV_BLOCK_ZERO; 149361007b31SStefan Hajnoczi } 149461007b31SStefan Hajnoczi } 149561007b31SStefan Hajnoczi } 149661007b31SStefan Hajnoczi 149761007b31SStefan Hajnoczi if (bs->file && 149861007b31SStefan Hajnoczi (ret & BDRV_BLOCK_DATA) && !(ret & BDRV_BLOCK_ZERO) && 149961007b31SStefan Hajnoczi (ret & BDRV_BLOCK_OFFSET_VALID)) { 150061007b31SStefan Hajnoczi int file_pnum; 150161007b31SStefan Hajnoczi 150261007b31SStefan Hajnoczi ret2 = bdrv_co_get_block_status(bs->file, ret >> BDRV_SECTOR_BITS, 150361007b31SStefan Hajnoczi *pnum, &file_pnum); 150461007b31SStefan Hajnoczi if (ret2 >= 0) { 150561007b31SStefan Hajnoczi /* Ignore errors. This is just providing extra information, it 150661007b31SStefan Hajnoczi * is useful but not necessary. 150761007b31SStefan Hajnoczi */ 150861007b31SStefan Hajnoczi if (!file_pnum) { 150961007b31SStefan Hajnoczi /* !file_pnum indicates an offset at or beyond the EOF; it is 151061007b31SStefan Hajnoczi * perfectly valid for the format block driver to point to such 151161007b31SStefan Hajnoczi * offsets, so catch it and mark everything as zero */ 151261007b31SStefan Hajnoczi ret |= BDRV_BLOCK_ZERO; 151361007b31SStefan Hajnoczi } else { 151461007b31SStefan Hajnoczi /* Limit request to the range reported by the protocol driver */ 151561007b31SStefan Hajnoczi *pnum = file_pnum; 151661007b31SStefan Hajnoczi ret |= (ret2 & BDRV_BLOCK_ZERO); 151761007b31SStefan Hajnoczi } 151861007b31SStefan Hajnoczi } 151961007b31SStefan Hajnoczi } 152061007b31SStefan Hajnoczi 152161007b31SStefan Hajnoczi return ret; 152261007b31SStefan Hajnoczi } 152361007b31SStefan Hajnoczi 152461007b31SStefan Hajnoczi /* Coroutine wrapper for bdrv_get_block_status() */ 152561007b31SStefan Hajnoczi static void coroutine_fn bdrv_get_block_status_co_entry(void *opaque) 152661007b31SStefan Hajnoczi { 152761007b31SStefan Hajnoczi BdrvCoGetBlockStatusData *data = opaque; 152861007b31SStefan Hajnoczi BlockDriverState *bs = data->bs; 152961007b31SStefan Hajnoczi 153061007b31SStefan Hajnoczi data->ret = bdrv_co_get_block_status(bs, data->sector_num, data->nb_sectors, 153161007b31SStefan Hajnoczi data->pnum); 153261007b31SStefan Hajnoczi data->done = true; 153361007b31SStefan Hajnoczi } 153461007b31SStefan Hajnoczi 153561007b31SStefan Hajnoczi /* 153661007b31SStefan Hajnoczi * Synchronous wrapper around bdrv_co_get_block_status(). 153761007b31SStefan Hajnoczi * 153861007b31SStefan Hajnoczi * See bdrv_co_get_block_status() for details. 153961007b31SStefan Hajnoczi */ 154061007b31SStefan Hajnoczi int64_t bdrv_get_block_status(BlockDriverState *bs, int64_t sector_num, 154161007b31SStefan Hajnoczi int nb_sectors, int *pnum) 154261007b31SStefan Hajnoczi { 154361007b31SStefan Hajnoczi Coroutine *co; 154461007b31SStefan Hajnoczi BdrvCoGetBlockStatusData data = { 154561007b31SStefan Hajnoczi .bs = bs, 154661007b31SStefan Hajnoczi .sector_num = sector_num, 154761007b31SStefan Hajnoczi .nb_sectors = nb_sectors, 154861007b31SStefan Hajnoczi .pnum = pnum, 154961007b31SStefan Hajnoczi .done = false, 155061007b31SStefan Hajnoczi }; 155161007b31SStefan Hajnoczi 155261007b31SStefan Hajnoczi if (qemu_in_coroutine()) { 155361007b31SStefan Hajnoczi /* Fast-path if already in coroutine context */ 155461007b31SStefan Hajnoczi bdrv_get_block_status_co_entry(&data); 155561007b31SStefan Hajnoczi } else { 155661007b31SStefan Hajnoczi AioContext *aio_context = bdrv_get_aio_context(bs); 155761007b31SStefan Hajnoczi 155861007b31SStefan Hajnoczi co = qemu_coroutine_create(bdrv_get_block_status_co_entry); 155961007b31SStefan Hajnoczi qemu_coroutine_enter(co, &data); 156061007b31SStefan Hajnoczi while (!data.done) { 156161007b31SStefan Hajnoczi aio_poll(aio_context, true); 156261007b31SStefan Hajnoczi } 156361007b31SStefan Hajnoczi } 156461007b31SStefan Hajnoczi return data.ret; 156561007b31SStefan Hajnoczi } 156661007b31SStefan Hajnoczi 156761007b31SStefan Hajnoczi int coroutine_fn bdrv_is_allocated(BlockDriverState *bs, int64_t sector_num, 156861007b31SStefan Hajnoczi int nb_sectors, int *pnum) 156961007b31SStefan Hajnoczi { 157061007b31SStefan Hajnoczi int64_t ret = bdrv_get_block_status(bs, sector_num, nb_sectors, pnum); 157161007b31SStefan Hajnoczi if (ret < 0) { 157261007b31SStefan Hajnoczi return ret; 157361007b31SStefan Hajnoczi } 157461007b31SStefan Hajnoczi return !!(ret & BDRV_BLOCK_ALLOCATED); 157561007b31SStefan Hajnoczi } 157661007b31SStefan Hajnoczi 157761007b31SStefan Hajnoczi /* 157861007b31SStefan Hajnoczi * Given an image chain: ... -> [BASE] -> [INTER1] -> [INTER2] -> [TOP] 157961007b31SStefan Hajnoczi * 158061007b31SStefan Hajnoczi * Return true if the given sector is allocated in any image between 158161007b31SStefan Hajnoczi * BASE and TOP (inclusive). BASE can be NULL to check if the given 158261007b31SStefan Hajnoczi * sector is allocated in any image of the chain. Return false otherwise. 158361007b31SStefan Hajnoczi * 158461007b31SStefan Hajnoczi * 'pnum' is set to the number of sectors (including and immediately following 158561007b31SStefan Hajnoczi * the specified sector) that are known to be in the same 158661007b31SStefan Hajnoczi * allocated/unallocated state. 158761007b31SStefan Hajnoczi * 158861007b31SStefan Hajnoczi */ 158961007b31SStefan Hajnoczi int bdrv_is_allocated_above(BlockDriverState *top, 159061007b31SStefan Hajnoczi BlockDriverState *base, 159161007b31SStefan Hajnoczi int64_t sector_num, 159261007b31SStefan Hajnoczi int nb_sectors, int *pnum) 159361007b31SStefan Hajnoczi { 159461007b31SStefan Hajnoczi BlockDriverState *intermediate; 159561007b31SStefan Hajnoczi int ret, n = nb_sectors; 159661007b31SStefan Hajnoczi 159761007b31SStefan Hajnoczi intermediate = top; 159861007b31SStefan Hajnoczi while (intermediate && intermediate != base) { 159961007b31SStefan Hajnoczi int pnum_inter; 160061007b31SStefan Hajnoczi ret = bdrv_is_allocated(intermediate, sector_num, nb_sectors, 160161007b31SStefan Hajnoczi &pnum_inter); 160261007b31SStefan Hajnoczi if (ret < 0) { 160361007b31SStefan Hajnoczi return ret; 160461007b31SStefan Hajnoczi } else if (ret) { 160561007b31SStefan Hajnoczi *pnum = pnum_inter; 160661007b31SStefan Hajnoczi return 1; 160761007b31SStefan Hajnoczi } 160861007b31SStefan Hajnoczi 160961007b31SStefan Hajnoczi /* 161061007b31SStefan Hajnoczi * [sector_num, nb_sectors] is unallocated on top but intermediate 161161007b31SStefan Hajnoczi * might have 161261007b31SStefan Hajnoczi * 161361007b31SStefan Hajnoczi * [sector_num+x, nr_sectors] allocated. 161461007b31SStefan Hajnoczi */ 161561007b31SStefan Hajnoczi if (n > pnum_inter && 161661007b31SStefan Hajnoczi (intermediate == top || 161761007b31SStefan Hajnoczi sector_num + pnum_inter < intermediate->total_sectors)) { 161861007b31SStefan Hajnoczi n = pnum_inter; 161961007b31SStefan Hajnoczi } 162061007b31SStefan Hajnoczi 162161007b31SStefan Hajnoczi intermediate = intermediate->backing_hd; 162261007b31SStefan Hajnoczi } 162361007b31SStefan Hajnoczi 162461007b31SStefan Hajnoczi *pnum = n; 162561007b31SStefan Hajnoczi return 0; 162661007b31SStefan Hajnoczi } 162761007b31SStefan Hajnoczi 162861007b31SStefan Hajnoczi int bdrv_write_compressed(BlockDriverState *bs, int64_t sector_num, 162961007b31SStefan Hajnoczi const uint8_t *buf, int nb_sectors) 163061007b31SStefan Hajnoczi { 163161007b31SStefan Hajnoczi BlockDriver *drv = bs->drv; 163261007b31SStefan Hajnoczi int ret; 163361007b31SStefan Hajnoczi 163461007b31SStefan Hajnoczi if (!drv) { 163561007b31SStefan Hajnoczi return -ENOMEDIUM; 163661007b31SStefan Hajnoczi } 163761007b31SStefan Hajnoczi if (!drv->bdrv_write_compressed) { 163861007b31SStefan Hajnoczi return -ENOTSUP; 163961007b31SStefan Hajnoczi } 164061007b31SStefan Hajnoczi ret = bdrv_check_request(bs, sector_num, nb_sectors); 164161007b31SStefan Hajnoczi if (ret < 0) { 164261007b31SStefan Hajnoczi return ret; 164361007b31SStefan Hajnoczi } 164461007b31SStefan Hajnoczi 164561007b31SStefan Hajnoczi assert(QLIST_EMPTY(&bs->dirty_bitmaps)); 164661007b31SStefan Hajnoczi 164761007b31SStefan Hajnoczi return drv->bdrv_write_compressed(bs, sector_num, buf, nb_sectors); 164861007b31SStefan Hajnoczi } 164961007b31SStefan Hajnoczi 165061007b31SStefan Hajnoczi int bdrv_save_vmstate(BlockDriverState *bs, const uint8_t *buf, 165161007b31SStefan Hajnoczi int64_t pos, int size) 165261007b31SStefan Hajnoczi { 165361007b31SStefan Hajnoczi QEMUIOVector qiov; 165461007b31SStefan Hajnoczi struct iovec iov = { 165561007b31SStefan Hajnoczi .iov_base = (void *) buf, 165661007b31SStefan Hajnoczi .iov_len = size, 165761007b31SStefan Hajnoczi }; 165861007b31SStefan Hajnoczi 165961007b31SStefan Hajnoczi qemu_iovec_init_external(&qiov, &iov, 1); 166061007b31SStefan Hajnoczi return bdrv_writev_vmstate(bs, &qiov, pos); 166161007b31SStefan Hajnoczi } 166261007b31SStefan Hajnoczi 166361007b31SStefan Hajnoczi int bdrv_writev_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos) 166461007b31SStefan Hajnoczi { 166561007b31SStefan Hajnoczi BlockDriver *drv = bs->drv; 166661007b31SStefan Hajnoczi 166761007b31SStefan Hajnoczi if (!drv) { 166861007b31SStefan Hajnoczi return -ENOMEDIUM; 166961007b31SStefan Hajnoczi } else if (drv->bdrv_save_vmstate) { 167061007b31SStefan Hajnoczi return drv->bdrv_save_vmstate(bs, qiov, pos); 167161007b31SStefan Hajnoczi } else if (bs->file) { 167261007b31SStefan Hajnoczi return bdrv_writev_vmstate(bs->file, qiov, pos); 167361007b31SStefan Hajnoczi } 167461007b31SStefan Hajnoczi 167561007b31SStefan Hajnoczi return -ENOTSUP; 167661007b31SStefan Hajnoczi } 167761007b31SStefan Hajnoczi 167861007b31SStefan Hajnoczi int bdrv_load_vmstate(BlockDriverState *bs, uint8_t *buf, 167961007b31SStefan Hajnoczi int64_t pos, int size) 168061007b31SStefan Hajnoczi { 168161007b31SStefan Hajnoczi BlockDriver *drv = bs->drv; 168261007b31SStefan Hajnoczi if (!drv) 168361007b31SStefan Hajnoczi return -ENOMEDIUM; 168461007b31SStefan Hajnoczi if (drv->bdrv_load_vmstate) 168561007b31SStefan Hajnoczi return drv->bdrv_load_vmstate(bs, buf, pos, size); 168661007b31SStefan Hajnoczi if (bs->file) 168761007b31SStefan Hajnoczi return bdrv_load_vmstate(bs->file, buf, pos, size); 168861007b31SStefan Hajnoczi return -ENOTSUP; 168961007b31SStefan Hajnoczi } 169061007b31SStefan Hajnoczi 169161007b31SStefan Hajnoczi /**************************************************************/ 169261007b31SStefan Hajnoczi /* async I/Os */ 169361007b31SStefan Hajnoczi 169461007b31SStefan Hajnoczi BlockAIOCB *bdrv_aio_readv(BlockDriverState *bs, int64_t sector_num, 169561007b31SStefan Hajnoczi QEMUIOVector *qiov, int nb_sectors, 169661007b31SStefan Hajnoczi BlockCompletionFunc *cb, void *opaque) 169761007b31SStefan Hajnoczi { 169861007b31SStefan Hajnoczi trace_bdrv_aio_readv(bs, sector_num, nb_sectors, opaque); 169961007b31SStefan Hajnoczi 170061007b31SStefan Hajnoczi return bdrv_co_aio_rw_vector(bs, sector_num, qiov, nb_sectors, 0, 170161007b31SStefan Hajnoczi cb, opaque, false); 170261007b31SStefan Hajnoczi } 170361007b31SStefan Hajnoczi 170461007b31SStefan Hajnoczi BlockAIOCB *bdrv_aio_writev(BlockDriverState *bs, int64_t sector_num, 170561007b31SStefan Hajnoczi QEMUIOVector *qiov, int nb_sectors, 170661007b31SStefan Hajnoczi BlockCompletionFunc *cb, void *opaque) 170761007b31SStefan Hajnoczi { 170861007b31SStefan Hajnoczi trace_bdrv_aio_writev(bs, sector_num, nb_sectors, opaque); 170961007b31SStefan Hajnoczi 171061007b31SStefan Hajnoczi return bdrv_co_aio_rw_vector(bs, sector_num, qiov, nb_sectors, 0, 171161007b31SStefan Hajnoczi cb, opaque, true); 171261007b31SStefan Hajnoczi } 171361007b31SStefan Hajnoczi 171461007b31SStefan Hajnoczi BlockAIOCB *bdrv_aio_write_zeroes(BlockDriverState *bs, 171561007b31SStefan Hajnoczi int64_t sector_num, int nb_sectors, BdrvRequestFlags flags, 171661007b31SStefan Hajnoczi BlockCompletionFunc *cb, void *opaque) 171761007b31SStefan Hajnoczi { 171861007b31SStefan Hajnoczi trace_bdrv_aio_write_zeroes(bs, sector_num, nb_sectors, flags, opaque); 171961007b31SStefan Hajnoczi 172061007b31SStefan Hajnoczi return bdrv_co_aio_rw_vector(bs, sector_num, NULL, nb_sectors, 172161007b31SStefan Hajnoczi BDRV_REQ_ZERO_WRITE | flags, 172261007b31SStefan Hajnoczi cb, opaque, true); 172361007b31SStefan Hajnoczi } 172461007b31SStefan Hajnoczi 172561007b31SStefan Hajnoczi 172661007b31SStefan Hajnoczi typedef struct MultiwriteCB { 172761007b31SStefan Hajnoczi int error; 172861007b31SStefan Hajnoczi int num_requests; 172961007b31SStefan Hajnoczi int num_callbacks; 173061007b31SStefan Hajnoczi struct { 173161007b31SStefan Hajnoczi BlockCompletionFunc *cb; 173261007b31SStefan Hajnoczi void *opaque; 173361007b31SStefan Hajnoczi QEMUIOVector *free_qiov; 173461007b31SStefan Hajnoczi } callbacks[]; 173561007b31SStefan Hajnoczi } MultiwriteCB; 173661007b31SStefan Hajnoczi 173761007b31SStefan Hajnoczi static void multiwrite_user_cb(MultiwriteCB *mcb) 173861007b31SStefan Hajnoczi { 173961007b31SStefan Hajnoczi int i; 174061007b31SStefan Hajnoczi 174161007b31SStefan Hajnoczi for (i = 0; i < mcb->num_callbacks; i++) { 174261007b31SStefan Hajnoczi mcb->callbacks[i].cb(mcb->callbacks[i].opaque, mcb->error); 174361007b31SStefan Hajnoczi if (mcb->callbacks[i].free_qiov) { 174461007b31SStefan Hajnoczi qemu_iovec_destroy(mcb->callbacks[i].free_qiov); 174561007b31SStefan Hajnoczi } 174661007b31SStefan Hajnoczi g_free(mcb->callbacks[i].free_qiov); 174761007b31SStefan Hajnoczi } 174861007b31SStefan Hajnoczi } 174961007b31SStefan Hajnoczi 175061007b31SStefan Hajnoczi static void multiwrite_cb(void *opaque, int ret) 175161007b31SStefan Hajnoczi { 175261007b31SStefan Hajnoczi MultiwriteCB *mcb = opaque; 175361007b31SStefan Hajnoczi 175461007b31SStefan Hajnoczi trace_multiwrite_cb(mcb, ret); 175561007b31SStefan Hajnoczi 175661007b31SStefan Hajnoczi if (ret < 0 && !mcb->error) { 175761007b31SStefan Hajnoczi mcb->error = ret; 175861007b31SStefan Hajnoczi } 175961007b31SStefan Hajnoczi 176061007b31SStefan Hajnoczi mcb->num_requests--; 176161007b31SStefan Hajnoczi if (mcb->num_requests == 0) { 176261007b31SStefan Hajnoczi multiwrite_user_cb(mcb); 176361007b31SStefan Hajnoczi g_free(mcb); 176461007b31SStefan Hajnoczi } 176561007b31SStefan Hajnoczi } 176661007b31SStefan Hajnoczi 176761007b31SStefan Hajnoczi static int multiwrite_req_compare(const void *a, const void *b) 176861007b31SStefan Hajnoczi { 176961007b31SStefan Hajnoczi const BlockRequest *req1 = a, *req2 = b; 177061007b31SStefan Hajnoczi 177161007b31SStefan Hajnoczi /* 177261007b31SStefan Hajnoczi * Note that we can't simply subtract req2->sector from req1->sector 177361007b31SStefan Hajnoczi * here as that could overflow the return value. 177461007b31SStefan Hajnoczi */ 177561007b31SStefan Hajnoczi if (req1->sector > req2->sector) { 177661007b31SStefan Hajnoczi return 1; 177761007b31SStefan Hajnoczi } else if (req1->sector < req2->sector) { 177861007b31SStefan Hajnoczi return -1; 177961007b31SStefan Hajnoczi } else { 178061007b31SStefan Hajnoczi return 0; 178161007b31SStefan Hajnoczi } 178261007b31SStefan Hajnoczi } 178361007b31SStefan Hajnoczi 178461007b31SStefan Hajnoczi /* 178561007b31SStefan Hajnoczi * Takes a bunch of requests and tries to merge them. Returns the number of 178661007b31SStefan Hajnoczi * requests that remain after merging. 178761007b31SStefan Hajnoczi */ 178861007b31SStefan Hajnoczi static int multiwrite_merge(BlockDriverState *bs, BlockRequest *reqs, 178961007b31SStefan Hajnoczi int num_reqs, MultiwriteCB *mcb) 179061007b31SStefan Hajnoczi { 179161007b31SStefan Hajnoczi int i, outidx; 179261007b31SStefan Hajnoczi 179361007b31SStefan Hajnoczi // Sort requests by start sector 179461007b31SStefan Hajnoczi qsort(reqs, num_reqs, sizeof(*reqs), &multiwrite_req_compare); 179561007b31SStefan Hajnoczi 179661007b31SStefan Hajnoczi // Check if adjacent requests touch the same clusters. If so, combine them, 179761007b31SStefan Hajnoczi // filling up gaps with zero sectors. 179861007b31SStefan Hajnoczi outidx = 0; 179961007b31SStefan Hajnoczi for (i = 1; i < num_reqs; i++) { 180061007b31SStefan Hajnoczi int merge = 0; 180161007b31SStefan Hajnoczi int64_t oldreq_last = reqs[outidx].sector + reqs[outidx].nb_sectors; 180261007b31SStefan Hajnoczi 180361007b31SStefan Hajnoczi // Handle exactly sequential writes and overlapping writes. 180461007b31SStefan Hajnoczi if (reqs[i].sector <= oldreq_last) { 180561007b31SStefan Hajnoczi merge = 1; 180661007b31SStefan Hajnoczi } 180761007b31SStefan Hajnoczi 180861007b31SStefan Hajnoczi if (reqs[outidx].qiov->niov + reqs[i].qiov->niov + 1 > IOV_MAX) { 180961007b31SStefan Hajnoczi merge = 0; 181061007b31SStefan Hajnoczi } 181161007b31SStefan Hajnoczi 181261007b31SStefan Hajnoczi if (bs->bl.max_transfer_length && reqs[outidx].nb_sectors + 181361007b31SStefan Hajnoczi reqs[i].nb_sectors > bs->bl.max_transfer_length) { 181461007b31SStefan Hajnoczi merge = 0; 181561007b31SStefan Hajnoczi } 181661007b31SStefan Hajnoczi 181761007b31SStefan Hajnoczi if (merge) { 181861007b31SStefan Hajnoczi size_t size; 181961007b31SStefan Hajnoczi QEMUIOVector *qiov = g_malloc0(sizeof(*qiov)); 182061007b31SStefan Hajnoczi qemu_iovec_init(qiov, 182161007b31SStefan Hajnoczi reqs[outidx].qiov->niov + reqs[i].qiov->niov + 1); 182261007b31SStefan Hajnoczi 182361007b31SStefan Hajnoczi // Add the first request to the merged one. If the requests are 182461007b31SStefan Hajnoczi // overlapping, drop the last sectors of the first request. 182561007b31SStefan Hajnoczi size = (reqs[i].sector - reqs[outidx].sector) << 9; 182661007b31SStefan Hajnoczi qemu_iovec_concat(qiov, reqs[outidx].qiov, 0, size); 182761007b31SStefan Hajnoczi 182861007b31SStefan Hajnoczi // We should need to add any zeros between the two requests 182961007b31SStefan Hajnoczi assert (reqs[i].sector <= oldreq_last); 183061007b31SStefan Hajnoczi 183161007b31SStefan Hajnoczi // Add the second request 183261007b31SStefan Hajnoczi qemu_iovec_concat(qiov, reqs[i].qiov, 0, reqs[i].qiov->size); 183361007b31SStefan Hajnoczi 183461007b31SStefan Hajnoczi // Add tail of first request, if necessary 183561007b31SStefan Hajnoczi if (qiov->size < reqs[outidx].qiov->size) { 183661007b31SStefan Hajnoczi qemu_iovec_concat(qiov, reqs[outidx].qiov, qiov->size, 183761007b31SStefan Hajnoczi reqs[outidx].qiov->size - qiov->size); 183861007b31SStefan Hajnoczi } 183961007b31SStefan Hajnoczi 184061007b31SStefan Hajnoczi reqs[outidx].nb_sectors = qiov->size >> 9; 184161007b31SStefan Hajnoczi reqs[outidx].qiov = qiov; 184261007b31SStefan Hajnoczi 184361007b31SStefan Hajnoczi mcb->callbacks[i].free_qiov = reqs[outidx].qiov; 184461007b31SStefan Hajnoczi } else { 184561007b31SStefan Hajnoczi outidx++; 184661007b31SStefan Hajnoczi reqs[outidx].sector = reqs[i].sector; 184761007b31SStefan Hajnoczi reqs[outidx].nb_sectors = reqs[i].nb_sectors; 184861007b31SStefan Hajnoczi reqs[outidx].qiov = reqs[i].qiov; 184961007b31SStefan Hajnoczi } 185061007b31SStefan Hajnoczi } 185161007b31SStefan Hajnoczi 185261007b31SStefan Hajnoczi block_acct_merge_done(&bs->stats, BLOCK_ACCT_WRITE, num_reqs - outidx - 1); 185361007b31SStefan Hajnoczi 185461007b31SStefan Hajnoczi return outidx + 1; 185561007b31SStefan Hajnoczi } 185661007b31SStefan Hajnoczi 185761007b31SStefan Hajnoczi /* 185861007b31SStefan Hajnoczi * Submit multiple AIO write requests at once. 185961007b31SStefan Hajnoczi * 186061007b31SStefan Hajnoczi * On success, the function returns 0 and all requests in the reqs array have 186161007b31SStefan Hajnoczi * been submitted. In error case this function returns -1, and any of the 186261007b31SStefan Hajnoczi * requests may or may not be submitted yet. In particular, this means that the 186361007b31SStefan Hajnoczi * callback will be called for some of the requests, for others it won't. The 186461007b31SStefan Hajnoczi * caller must check the error field of the BlockRequest to wait for the right 186561007b31SStefan Hajnoczi * callbacks (if error != 0, no callback will be called). 186661007b31SStefan Hajnoczi * 186761007b31SStefan Hajnoczi * The implementation may modify the contents of the reqs array, e.g. to merge 186861007b31SStefan Hajnoczi * requests. However, the fields opaque and error are left unmodified as they 186961007b31SStefan Hajnoczi * are used to signal failure for a single request to the caller. 187061007b31SStefan Hajnoczi */ 187161007b31SStefan Hajnoczi int bdrv_aio_multiwrite(BlockDriverState *bs, BlockRequest *reqs, int num_reqs) 187261007b31SStefan Hajnoczi { 187361007b31SStefan Hajnoczi MultiwriteCB *mcb; 187461007b31SStefan Hajnoczi int i; 187561007b31SStefan Hajnoczi 187661007b31SStefan Hajnoczi /* don't submit writes if we don't have a medium */ 187761007b31SStefan Hajnoczi if (bs->drv == NULL) { 187861007b31SStefan Hajnoczi for (i = 0; i < num_reqs; i++) { 187961007b31SStefan Hajnoczi reqs[i].error = -ENOMEDIUM; 188061007b31SStefan Hajnoczi } 188161007b31SStefan Hajnoczi return -1; 188261007b31SStefan Hajnoczi } 188361007b31SStefan Hajnoczi 188461007b31SStefan Hajnoczi if (num_reqs == 0) { 188561007b31SStefan Hajnoczi return 0; 188661007b31SStefan Hajnoczi } 188761007b31SStefan Hajnoczi 188861007b31SStefan Hajnoczi // Create MultiwriteCB structure 188961007b31SStefan Hajnoczi mcb = g_malloc0(sizeof(*mcb) + num_reqs * sizeof(*mcb->callbacks)); 189061007b31SStefan Hajnoczi mcb->num_requests = 0; 189161007b31SStefan Hajnoczi mcb->num_callbacks = num_reqs; 189261007b31SStefan Hajnoczi 189361007b31SStefan Hajnoczi for (i = 0; i < num_reqs; i++) { 189461007b31SStefan Hajnoczi mcb->callbacks[i].cb = reqs[i].cb; 189561007b31SStefan Hajnoczi mcb->callbacks[i].opaque = reqs[i].opaque; 189661007b31SStefan Hajnoczi } 189761007b31SStefan Hajnoczi 189861007b31SStefan Hajnoczi // Check for mergable requests 189961007b31SStefan Hajnoczi num_reqs = multiwrite_merge(bs, reqs, num_reqs, mcb); 190061007b31SStefan Hajnoczi 190161007b31SStefan Hajnoczi trace_bdrv_aio_multiwrite(mcb, mcb->num_callbacks, num_reqs); 190261007b31SStefan Hajnoczi 190361007b31SStefan Hajnoczi /* Run the aio requests. */ 190461007b31SStefan Hajnoczi mcb->num_requests = num_reqs; 190561007b31SStefan Hajnoczi for (i = 0; i < num_reqs; i++) { 190661007b31SStefan Hajnoczi bdrv_co_aio_rw_vector(bs, reqs[i].sector, reqs[i].qiov, 190761007b31SStefan Hajnoczi reqs[i].nb_sectors, reqs[i].flags, 190861007b31SStefan Hajnoczi multiwrite_cb, mcb, 190961007b31SStefan Hajnoczi true); 191061007b31SStefan Hajnoczi } 191161007b31SStefan Hajnoczi 191261007b31SStefan Hajnoczi return 0; 191361007b31SStefan Hajnoczi } 191461007b31SStefan Hajnoczi 191561007b31SStefan Hajnoczi void bdrv_aio_cancel(BlockAIOCB *acb) 191661007b31SStefan Hajnoczi { 191761007b31SStefan Hajnoczi qemu_aio_ref(acb); 191861007b31SStefan Hajnoczi bdrv_aio_cancel_async(acb); 191961007b31SStefan Hajnoczi while (acb->refcnt > 1) { 192061007b31SStefan Hajnoczi if (acb->aiocb_info->get_aio_context) { 192161007b31SStefan Hajnoczi aio_poll(acb->aiocb_info->get_aio_context(acb), true); 192261007b31SStefan Hajnoczi } else if (acb->bs) { 192361007b31SStefan Hajnoczi aio_poll(bdrv_get_aio_context(acb->bs), true); 192461007b31SStefan Hajnoczi } else { 192561007b31SStefan Hajnoczi abort(); 192661007b31SStefan Hajnoczi } 192761007b31SStefan Hajnoczi } 192861007b31SStefan Hajnoczi qemu_aio_unref(acb); 192961007b31SStefan Hajnoczi } 193061007b31SStefan Hajnoczi 193161007b31SStefan Hajnoczi /* Async version of aio cancel. The caller is not blocked if the acb implements 193261007b31SStefan Hajnoczi * cancel_async, otherwise we do nothing and let the request normally complete. 193361007b31SStefan Hajnoczi * In either case the completion callback must be called. */ 193461007b31SStefan Hajnoczi void bdrv_aio_cancel_async(BlockAIOCB *acb) 193561007b31SStefan Hajnoczi { 193661007b31SStefan Hajnoczi if (acb->aiocb_info->cancel_async) { 193761007b31SStefan Hajnoczi acb->aiocb_info->cancel_async(acb); 193861007b31SStefan Hajnoczi } 193961007b31SStefan Hajnoczi } 194061007b31SStefan Hajnoczi 194161007b31SStefan Hajnoczi /**************************************************************/ 194261007b31SStefan Hajnoczi /* async block device emulation */ 194361007b31SStefan Hajnoczi 194461007b31SStefan Hajnoczi typedef struct BlockAIOCBSync { 194561007b31SStefan Hajnoczi BlockAIOCB common; 194661007b31SStefan Hajnoczi QEMUBH *bh; 194761007b31SStefan Hajnoczi int ret; 194861007b31SStefan Hajnoczi /* vector translation state */ 194961007b31SStefan Hajnoczi QEMUIOVector *qiov; 195061007b31SStefan Hajnoczi uint8_t *bounce; 195161007b31SStefan Hajnoczi int is_write; 195261007b31SStefan Hajnoczi } BlockAIOCBSync; 195361007b31SStefan Hajnoczi 195461007b31SStefan Hajnoczi static const AIOCBInfo bdrv_em_aiocb_info = { 195561007b31SStefan Hajnoczi .aiocb_size = sizeof(BlockAIOCBSync), 195661007b31SStefan Hajnoczi }; 195761007b31SStefan Hajnoczi 195861007b31SStefan Hajnoczi static void bdrv_aio_bh_cb(void *opaque) 195961007b31SStefan Hajnoczi { 196061007b31SStefan Hajnoczi BlockAIOCBSync *acb = opaque; 196161007b31SStefan Hajnoczi 196261007b31SStefan Hajnoczi if (!acb->is_write && acb->ret >= 0) { 196361007b31SStefan Hajnoczi qemu_iovec_from_buf(acb->qiov, 0, acb->bounce, acb->qiov->size); 196461007b31SStefan Hajnoczi } 196561007b31SStefan Hajnoczi qemu_vfree(acb->bounce); 196661007b31SStefan Hajnoczi acb->common.cb(acb->common.opaque, acb->ret); 196761007b31SStefan Hajnoczi qemu_bh_delete(acb->bh); 196861007b31SStefan Hajnoczi acb->bh = NULL; 196961007b31SStefan Hajnoczi qemu_aio_unref(acb); 197061007b31SStefan Hajnoczi } 197161007b31SStefan Hajnoczi 197261007b31SStefan Hajnoczi static BlockAIOCB *bdrv_aio_rw_vector(BlockDriverState *bs, 197361007b31SStefan Hajnoczi int64_t sector_num, 197461007b31SStefan Hajnoczi QEMUIOVector *qiov, 197561007b31SStefan Hajnoczi int nb_sectors, 197661007b31SStefan Hajnoczi BlockCompletionFunc *cb, 197761007b31SStefan Hajnoczi void *opaque, 197861007b31SStefan Hajnoczi int is_write) 197961007b31SStefan Hajnoczi 198061007b31SStefan Hajnoczi { 198161007b31SStefan Hajnoczi BlockAIOCBSync *acb; 198261007b31SStefan Hajnoczi 198361007b31SStefan Hajnoczi acb = qemu_aio_get(&bdrv_em_aiocb_info, bs, cb, opaque); 198461007b31SStefan Hajnoczi acb->is_write = is_write; 198561007b31SStefan Hajnoczi acb->qiov = qiov; 198661007b31SStefan Hajnoczi acb->bounce = qemu_try_blockalign(bs, qiov->size); 198761007b31SStefan Hajnoczi acb->bh = aio_bh_new(bdrv_get_aio_context(bs), bdrv_aio_bh_cb, acb); 198861007b31SStefan Hajnoczi 198961007b31SStefan Hajnoczi if (acb->bounce == NULL) { 199061007b31SStefan Hajnoczi acb->ret = -ENOMEM; 199161007b31SStefan Hajnoczi } else if (is_write) { 199261007b31SStefan Hajnoczi qemu_iovec_to_buf(acb->qiov, 0, acb->bounce, qiov->size); 199361007b31SStefan Hajnoczi acb->ret = bs->drv->bdrv_write(bs, sector_num, acb->bounce, nb_sectors); 199461007b31SStefan Hajnoczi } else { 199561007b31SStefan Hajnoczi acb->ret = bs->drv->bdrv_read(bs, sector_num, acb->bounce, nb_sectors); 199661007b31SStefan Hajnoczi } 199761007b31SStefan Hajnoczi 199861007b31SStefan Hajnoczi qemu_bh_schedule(acb->bh); 199961007b31SStefan Hajnoczi 200061007b31SStefan Hajnoczi return &acb->common; 200161007b31SStefan Hajnoczi } 200261007b31SStefan Hajnoczi 200361007b31SStefan Hajnoczi static BlockAIOCB *bdrv_aio_readv_em(BlockDriverState *bs, 200461007b31SStefan Hajnoczi int64_t sector_num, QEMUIOVector *qiov, int nb_sectors, 200561007b31SStefan Hajnoczi BlockCompletionFunc *cb, void *opaque) 200661007b31SStefan Hajnoczi { 200761007b31SStefan Hajnoczi return bdrv_aio_rw_vector(bs, sector_num, qiov, nb_sectors, cb, opaque, 0); 200861007b31SStefan Hajnoczi } 200961007b31SStefan Hajnoczi 201061007b31SStefan Hajnoczi static BlockAIOCB *bdrv_aio_writev_em(BlockDriverState *bs, 201161007b31SStefan Hajnoczi int64_t sector_num, QEMUIOVector *qiov, int nb_sectors, 201261007b31SStefan Hajnoczi BlockCompletionFunc *cb, void *opaque) 201361007b31SStefan Hajnoczi { 201461007b31SStefan Hajnoczi return bdrv_aio_rw_vector(bs, sector_num, qiov, nb_sectors, cb, opaque, 1); 201561007b31SStefan Hajnoczi } 201661007b31SStefan Hajnoczi 201761007b31SStefan Hajnoczi 201861007b31SStefan Hajnoczi typedef struct BlockAIOCBCoroutine { 201961007b31SStefan Hajnoczi BlockAIOCB common; 202061007b31SStefan Hajnoczi BlockRequest req; 202161007b31SStefan Hajnoczi bool is_write; 202261007b31SStefan Hajnoczi bool need_bh; 202361007b31SStefan Hajnoczi bool *done; 202461007b31SStefan Hajnoczi QEMUBH* bh; 202561007b31SStefan Hajnoczi } BlockAIOCBCoroutine; 202661007b31SStefan Hajnoczi 202761007b31SStefan Hajnoczi static const AIOCBInfo bdrv_em_co_aiocb_info = { 202861007b31SStefan Hajnoczi .aiocb_size = sizeof(BlockAIOCBCoroutine), 202961007b31SStefan Hajnoczi }; 203061007b31SStefan Hajnoczi 203161007b31SStefan Hajnoczi static void bdrv_co_complete(BlockAIOCBCoroutine *acb) 203261007b31SStefan Hajnoczi { 203361007b31SStefan Hajnoczi if (!acb->need_bh) { 203461007b31SStefan Hajnoczi acb->common.cb(acb->common.opaque, acb->req.error); 203561007b31SStefan Hajnoczi qemu_aio_unref(acb); 203661007b31SStefan Hajnoczi } 203761007b31SStefan Hajnoczi } 203861007b31SStefan Hajnoczi 203961007b31SStefan Hajnoczi static void bdrv_co_em_bh(void *opaque) 204061007b31SStefan Hajnoczi { 204161007b31SStefan Hajnoczi BlockAIOCBCoroutine *acb = opaque; 204261007b31SStefan Hajnoczi 204361007b31SStefan Hajnoczi assert(!acb->need_bh); 204461007b31SStefan Hajnoczi qemu_bh_delete(acb->bh); 204561007b31SStefan Hajnoczi bdrv_co_complete(acb); 204661007b31SStefan Hajnoczi } 204761007b31SStefan Hajnoczi 204861007b31SStefan Hajnoczi static void bdrv_co_maybe_schedule_bh(BlockAIOCBCoroutine *acb) 204961007b31SStefan Hajnoczi { 205061007b31SStefan Hajnoczi acb->need_bh = false; 205161007b31SStefan Hajnoczi if (acb->req.error != -EINPROGRESS) { 205261007b31SStefan Hajnoczi BlockDriverState *bs = acb->common.bs; 205361007b31SStefan Hajnoczi 205461007b31SStefan Hajnoczi acb->bh = aio_bh_new(bdrv_get_aio_context(bs), bdrv_co_em_bh, acb); 205561007b31SStefan Hajnoczi qemu_bh_schedule(acb->bh); 205661007b31SStefan Hajnoczi } 205761007b31SStefan Hajnoczi } 205861007b31SStefan Hajnoczi 205961007b31SStefan Hajnoczi /* Invoke bdrv_co_do_readv/bdrv_co_do_writev */ 206061007b31SStefan Hajnoczi static void coroutine_fn bdrv_co_do_rw(void *opaque) 206161007b31SStefan Hajnoczi { 206261007b31SStefan Hajnoczi BlockAIOCBCoroutine *acb = opaque; 206361007b31SStefan Hajnoczi BlockDriverState *bs = acb->common.bs; 206461007b31SStefan Hajnoczi 206561007b31SStefan Hajnoczi if (!acb->is_write) { 206661007b31SStefan Hajnoczi acb->req.error = bdrv_co_do_readv(bs, acb->req.sector, 206761007b31SStefan Hajnoczi acb->req.nb_sectors, acb->req.qiov, acb->req.flags); 206861007b31SStefan Hajnoczi } else { 206961007b31SStefan Hajnoczi acb->req.error = bdrv_co_do_writev(bs, acb->req.sector, 207061007b31SStefan Hajnoczi acb->req.nb_sectors, acb->req.qiov, acb->req.flags); 207161007b31SStefan Hajnoczi } 207261007b31SStefan Hajnoczi 207361007b31SStefan Hajnoczi bdrv_co_complete(acb); 207461007b31SStefan Hajnoczi } 207561007b31SStefan Hajnoczi 207661007b31SStefan Hajnoczi static BlockAIOCB *bdrv_co_aio_rw_vector(BlockDriverState *bs, 207761007b31SStefan Hajnoczi int64_t sector_num, 207861007b31SStefan Hajnoczi QEMUIOVector *qiov, 207961007b31SStefan Hajnoczi int nb_sectors, 208061007b31SStefan Hajnoczi BdrvRequestFlags flags, 208161007b31SStefan Hajnoczi BlockCompletionFunc *cb, 208261007b31SStefan Hajnoczi void *opaque, 208361007b31SStefan Hajnoczi bool is_write) 208461007b31SStefan Hajnoczi { 208561007b31SStefan Hajnoczi Coroutine *co; 208661007b31SStefan Hajnoczi BlockAIOCBCoroutine *acb; 208761007b31SStefan Hajnoczi 208861007b31SStefan Hajnoczi acb = qemu_aio_get(&bdrv_em_co_aiocb_info, bs, cb, opaque); 208961007b31SStefan Hajnoczi acb->need_bh = true; 209061007b31SStefan Hajnoczi acb->req.error = -EINPROGRESS; 209161007b31SStefan Hajnoczi acb->req.sector = sector_num; 209261007b31SStefan Hajnoczi acb->req.nb_sectors = nb_sectors; 209361007b31SStefan Hajnoczi acb->req.qiov = qiov; 209461007b31SStefan Hajnoczi acb->req.flags = flags; 209561007b31SStefan Hajnoczi acb->is_write = is_write; 209661007b31SStefan Hajnoczi 209761007b31SStefan Hajnoczi co = qemu_coroutine_create(bdrv_co_do_rw); 209861007b31SStefan Hajnoczi qemu_coroutine_enter(co, acb); 209961007b31SStefan Hajnoczi 210061007b31SStefan Hajnoczi bdrv_co_maybe_schedule_bh(acb); 210161007b31SStefan Hajnoczi return &acb->common; 210261007b31SStefan Hajnoczi } 210361007b31SStefan Hajnoczi 210461007b31SStefan Hajnoczi static void coroutine_fn bdrv_aio_flush_co_entry(void *opaque) 210561007b31SStefan Hajnoczi { 210661007b31SStefan Hajnoczi BlockAIOCBCoroutine *acb = opaque; 210761007b31SStefan Hajnoczi BlockDriverState *bs = acb->common.bs; 210861007b31SStefan Hajnoczi 210961007b31SStefan Hajnoczi acb->req.error = bdrv_co_flush(bs); 211061007b31SStefan Hajnoczi bdrv_co_complete(acb); 211161007b31SStefan Hajnoczi } 211261007b31SStefan Hajnoczi 211361007b31SStefan Hajnoczi BlockAIOCB *bdrv_aio_flush(BlockDriverState *bs, 211461007b31SStefan Hajnoczi BlockCompletionFunc *cb, void *opaque) 211561007b31SStefan Hajnoczi { 211661007b31SStefan Hajnoczi trace_bdrv_aio_flush(bs, opaque); 211761007b31SStefan Hajnoczi 211861007b31SStefan Hajnoczi Coroutine *co; 211961007b31SStefan Hajnoczi BlockAIOCBCoroutine *acb; 212061007b31SStefan Hajnoczi 212161007b31SStefan Hajnoczi acb = qemu_aio_get(&bdrv_em_co_aiocb_info, bs, cb, opaque); 212261007b31SStefan Hajnoczi acb->need_bh = true; 212361007b31SStefan Hajnoczi acb->req.error = -EINPROGRESS; 212461007b31SStefan Hajnoczi 212561007b31SStefan Hajnoczi co = qemu_coroutine_create(bdrv_aio_flush_co_entry); 212661007b31SStefan Hajnoczi qemu_coroutine_enter(co, acb); 212761007b31SStefan Hajnoczi 212861007b31SStefan Hajnoczi bdrv_co_maybe_schedule_bh(acb); 212961007b31SStefan Hajnoczi return &acb->common; 213061007b31SStefan Hajnoczi } 213161007b31SStefan Hajnoczi 213261007b31SStefan Hajnoczi static void coroutine_fn bdrv_aio_discard_co_entry(void *opaque) 213361007b31SStefan Hajnoczi { 213461007b31SStefan Hajnoczi BlockAIOCBCoroutine *acb = opaque; 213561007b31SStefan Hajnoczi BlockDriverState *bs = acb->common.bs; 213661007b31SStefan Hajnoczi 213761007b31SStefan Hajnoczi acb->req.error = bdrv_co_discard(bs, acb->req.sector, acb->req.nb_sectors); 213861007b31SStefan Hajnoczi bdrv_co_complete(acb); 213961007b31SStefan Hajnoczi } 214061007b31SStefan Hajnoczi 214161007b31SStefan Hajnoczi BlockAIOCB *bdrv_aio_discard(BlockDriverState *bs, 214261007b31SStefan Hajnoczi int64_t sector_num, int nb_sectors, 214361007b31SStefan Hajnoczi BlockCompletionFunc *cb, void *opaque) 214461007b31SStefan Hajnoczi { 214561007b31SStefan Hajnoczi Coroutine *co; 214661007b31SStefan Hajnoczi BlockAIOCBCoroutine *acb; 214761007b31SStefan Hajnoczi 214861007b31SStefan Hajnoczi trace_bdrv_aio_discard(bs, sector_num, nb_sectors, opaque); 214961007b31SStefan Hajnoczi 215061007b31SStefan Hajnoczi acb = qemu_aio_get(&bdrv_em_co_aiocb_info, bs, cb, opaque); 215161007b31SStefan Hajnoczi acb->need_bh = true; 215261007b31SStefan Hajnoczi acb->req.error = -EINPROGRESS; 215361007b31SStefan Hajnoczi acb->req.sector = sector_num; 215461007b31SStefan Hajnoczi acb->req.nb_sectors = nb_sectors; 215561007b31SStefan Hajnoczi co = qemu_coroutine_create(bdrv_aio_discard_co_entry); 215661007b31SStefan Hajnoczi qemu_coroutine_enter(co, acb); 215761007b31SStefan Hajnoczi 215861007b31SStefan Hajnoczi bdrv_co_maybe_schedule_bh(acb); 215961007b31SStefan Hajnoczi return &acb->common; 216061007b31SStefan Hajnoczi } 216161007b31SStefan Hajnoczi 216261007b31SStefan Hajnoczi void *qemu_aio_get(const AIOCBInfo *aiocb_info, BlockDriverState *bs, 216361007b31SStefan Hajnoczi BlockCompletionFunc *cb, void *opaque) 216461007b31SStefan Hajnoczi { 216561007b31SStefan Hajnoczi BlockAIOCB *acb; 216661007b31SStefan Hajnoczi 216761007b31SStefan Hajnoczi acb = g_slice_alloc(aiocb_info->aiocb_size); 216861007b31SStefan Hajnoczi acb->aiocb_info = aiocb_info; 216961007b31SStefan Hajnoczi acb->bs = bs; 217061007b31SStefan Hajnoczi acb->cb = cb; 217161007b31SStefan Hajnoczi acb->opaque = opaque; 217261007b31SStefan Hajnoczi acb->refcnt = 1; 217361007b31SStefan Hajnoczi return acb; 217461007b31SStefan Hajnoczi } 217561007b31SStefan Hajnoczi 217661007b31SStefan Hajnoczi void qemu_aio_ref(void *p) 217761007b31SStefan Hajnoczi { 217861007b31SStefan Hajnoczi BlockAIOCB *acb = p; 217961007b31SStefan Hajnoczi acb->refcnt++; 218061007b31SStefan Hajnoczi } 218161007b31SStefan Hajnoczi 218261007b31SStefan Hajnoczi void qemu_aio_unref(void *p) 218361007b31SStefan Hajnoczi { 218461007b31SStefan Hajnoczi BlockAIOCB *acb = p; 218561007b31SStefan Hajnoczi assert(acb->refcnt > 0); 218661007b31SStefan Hajnoczi if (--acb->refcnt == 0) { 218761007b31SStefan Hajnoczi g_slice_free1(acb->aiocb_info->aiocb_size, acb); 218861007b31SStefan Hajnoczi } 218961007b31SStefan Hajnoczi } 219061007b31SStefan Hajnoczi 219161007b31SStefan Hajnoczi /**************************************************************/ 219261007b31SStefan Hajnoczi /* Coroutine block device emulation */ 219361007b31SStefan Hajnoczi 219461007b31SStefan Hajnoczi typedef struct CoroutineIOCompletion { 219561007b31SStefan Hajnoczi Coroutine *coroutine; 219661007b31SStefan Hajnoczi int ret; 219761007b31SStefan Hajnoczi } CoroutineIOCompletion; 219861007b31SStefan Hajnoczi 219961007b31SStefan Hajnoczi static void bdrv_co_io_em_complete(void *opaque, int ret) 220061007b31SStefan Hajnoczi { 220161007b31SStefan Hajnoczi CoroutineIOCompletion *co = opaque; 220261007b31SStefan Hajnoczi 220361007b31SStefan Hajnoczi co->ret = ret; 220461007b31SStefan Hajnoczi qemu_coroutine_enter(co->coroutine, NULL); 220561007b31SStefan Hajnoczi } 220661007b31SStefan Hajnoczi 220761007b31SStefan Hajnoczi static int coroutine_fn bdrv_co_io_em(BlockDriverState *bs, int64_t sector_num, 220861007b31SStefan Hajnoczi int nb_sectors, QEMUIOVector *iov, 220961007b31SStefan Hajnoczi bool is_write) 221061007b31SStefan Hajnoczi { 221161007b31SStefan Hajnoczi CoroutineIOCompletion co = { 221261007b31SStefan Hajnoczi .coroutine = qemu_coroutine_self(), 221361007b31SStefan Hajnoczi }; 221461007b31SStefan Hajnoczi BlockAIOCB *acb; 221561007b31SStefan Hajnoczi 221661007b31SStefan Hajnoczi if (is_write) { 221761007b31SStefan Hajnoczi acb = bs->drv->bdrv_aio_writev(bs, sector_num, iov, nb_sectors, 221861007b31SStefan Hajnoczi bdrv_co_io_em_complete, &co); 221961007b31SStefan Hajnoczi } else { 222061007b31SStefan Hajnoczi acb = bs->drv->bdrv_aio_readv(bs, sector_num, iov, nb_sectors, 222161007b31SStefan Hajnoczi bdrv_co_io_em_complete, &co); 222261007b31SStefan Hajnoczi } 222361007b31SStefan Hajnoczi 222461007b31SStefan Hajnoczi trace_bdrv_co_io_em(bs, sector_num, nb_sectors, is_write, acb); 222561007b31SStefan Hajnoczi if (!acb) { 222661007b31SStefan Hajnoczi return -EIO; 222761007b31SStefan Hajnoczi } 222861007b31SStefan Hajnoczi qemu_coroutine_yield(); 222961007b31SStefan Hajnoczi 223061007b31SStefan Hajnoczi return co.ret; 223161007b31SStefan Hajnoczi } 223261007b31SStefan Hajnoczi 223361007b31SStefan Hajnoczi static int coroutine_fn bdrv_co_readv_em(BlockDriverState *bs, 223461007b31SStefan Hajnoczi int64_t sector_num, int nb_sectors, 223561007b31SStefan Hajnoczi QEMUIOVector *iov) 223661007b31SStefan Hajnoczi { 223761007b31SStefan Hajnoczi return bdrv_co_io_em(bs, sector_num, nb_sectors, iov, false); 223861007b31SStefan Hajnoczi } 223961007b31SStefan Hajnoczi 224061007b31SStefan Hajnoczi static int coroutine_fn bdrv_co_writev_em(BlockDriverState *bs, 224161007b31SStefan Hajnoczi int64_t sector_num, int nb_sectors, 224261007b31SStefan Hajnoczi QEMUIOVector *iov) 224361007b31SStefan Hajnoczi { 224461007b31SStefan Hajnoczi return bdrv_co_io_em(bs, sector_num, nb_sectors, iov, true); 224561007b31SStefan Hajnoczi } 224661007b31SStefan Hajnoczi 224761007b31SStefan Hajnoczi static void coroutine_fn bdrv_flush_co_entry(void *opaque) 224861007b31SStefan Hajnoczi { 224961007b31SStefan Hajnoczi RwCo *rwco = opaque; 225061007b31SStefan Hajnoczi 225161007b31SStefan Hajnoczi rwco->ret = bdrv_co_flush(rwco->bs); 225261007b31SStefan Hajnoczi } 225361007b31SStefan Hajnoczi 225461007b31SStefan Hajnoczi int coroutine_fn bdrv_co_flush(BlockDriverState *bs) 225561007b31SStefan Hajnoczi { 225661007b31SStefan Hajnoczi int ret; 225761007b31SStefan Hajnoczi 225861007b31SStefan Hajnoczi if (!bs || !bdrv_is_inserted(bs) || bdrv_is_read_only(bs)) { 225961007b31SStefan Hajnoczi return 0; 226061007b31SStefan Hajnoczi } 226161007b31SStefan Hajnoczi 226261007b31SStefan Hajnoczi /* Write back cached data to the OS even with cache=unsafe */ 226361007b31SStefan Hajnoczi BLKDBG_EVENT(bs->file, BLKDBG_FLUSH_TO_OS); 226461007b31SStefan Hajnoczi if (bs->drv->bdrv_co_flush_to_os) { 226561007b31SStefan Hajnoczi ret = bs->drv->bdrv_co_flush_to_os(bs); 226661007b31SStefan Hajnoczi if (ret < 0) { 226761007b31SStefan Hajnoczi return ret; 226861007b31SStefan Hajnoczi } 226961007b31SStefan Hajnoczi } 227061007b31SStefan Hajnoczi 227161007b31SStefan Hajnoczi /* But don't actually force it to the disk with cache=unsafe */ 227261007b31SStefan Hajnoczi if (bs->open_flags & BDRV_O_NO_FLUSH) { 227361007b31SStefan Hajnoczi goto flush_parent; 227461007b31SStefan Hajnoczi } 227561007b31SStefan Hajnoczi 227661007b31SStefan Hajnoczi BLKDBG_EVENT(bs->file, BLKDBG_FLUSH_TO_DISK); 227761007b31SStefan Hajnoczi if (bs->drv->bdrv_co_flush_to_disk) { 227861007b31SStefan Hajnoczi ret = bs->drv->bdrv_co_flush_to_disk(bs); 227961007b31SStefan Hajnoczi } else if (bs->drv->bdrv_aio_flush) { 228061007b31SStefan Hajnoczi BlockAIOCB *acb; 228161007b31SStefan Hajnoczi CoroutineIOCompletion co = { 228261007b31SStefan Hajnoczi .coroutine = qemu_coroutine_self(), 228361007b31SStefan Hajnoczi }; 228461007b31SStefan Hajnoczi 228561007b31SStefan Hajnoczi acb = bs->drv->bdrv_aio_flush(bs, bdrv_co_io_em_complete, &co); 228661007b31SStefan Hajnoczi if (acb == NULL) { 228761007b31SStefan Hajnoczi ret = -EIO; 228861007b31SStefan Hajnoczi } else { 228961007b31SStefan Hajnoczi qemu_coroutine_yield(); 229061007b31SStefan Hajnoczi ret = co.ret; 229161007b31SStefan Hajnoczi } 229261007b31SStefan Hajnoczi } else { 229361007b31SStefan Hajnoczi /* 229461007b31SStefan Hajnoczi * Some block drivers always operate in either writethrough or unsafe 229561007b31SStefan Hajnoczi * mode and don't support bdrv_flush therefore. Usually qemu doesn't 229661007b31SStefan Hajnoczi * know how the server works (because the behaviour is hardcoded or 229761007b31SStefan Hajnoczi * depends on server-side configuration), so we can't ensure that 229861007b31SStefan Hajnoczi * everything is safe on disk. Returning an error doesn't work because 229961007b31SStefan Hajnoczi * that would break guests even if the server operates in writethrough 230061007b31SStefan Hajnoczi * mode. 230161007b31SStefan Hajnoczi * 230261007b31SStefan Hajnoczi * Let's hope the user knows what he's doing. 230361007b31SStefan Hajnoczi */ 230461007b31SStefan Hajnoczi ret = 0; 230561007b31SStefan Hajnoczi } 230661007b31SStefan Hajnoczi if (ret < 0) { 230761007b31SStefan Hajnoczi return ret; 230861007b31SStefan Hajnoczi } 230961007b31SStefan Hajnoczi 231061007b31SStefan Hajnoczi /* Now flush the underlying protocol. It will also have BDRV_O_NO_FLUSH 231161007b31SStefan Hajnoczi * in the case of cache=unsafe, so there are no useless flushes. 231261007b31SStefan Hajnoczi */ 231361007b31SStefan Hajnoczi flush_parent: 231461007b31SStefan Hajnoczi return bdrv_co_flush(bs->file); 231561007b31SStefan Hajnoczi } 231661007b31SStefan Hajnoczi 231761007b31SStefan Hajnoczi int bdrv_flush(BlockDriverState *bs) 231861007b31SStefan Hajnoczi { 231961007b31SStefan Hajnoczi Coroutine *co; 232061007b31SStefan Hajnoczi RwCo rwco = { 232161007b31SStefan Hajnoczi .bs = bs, 232261007b31SStefan Hajnoczi .ret = NOT_DONE, 232361007b31SStefan Hajnoczi }; 232461007b31SStefan Hajnoczi 232561007b31SStefan Hajnoczi if (qemu_in_coroutine()) { 232661007b31SStefan Hajnoczi /* Fast-path if already in coroutine context */ 232761007b31SStefan Hajnoczi bdrv_flush_co_entry(&rwco); 232861007b31SStefan Hajnoczi } else { 232961007b31SStefan Hajnoczi AioContext *aio_context = bdrv_get_aio_context(bs); 233061007b31SStefan Hajnoczi 233161007b31SStefan Hajnoczi co = qemu_coroutine_create(bdrv_flush_co_entry); 233261007b31SStefan Hajnoczi qemu_coroutine_enter(co, &rwco); 233361007b31SStefan Hajnoczi while (rwco.ret == NOT_DONE) { 233461007b31SStefan Hajnoczi aio_poll(aio_context, true); 233561007b31SStefan Hajnoczi } 233661007b31SStefan Hajnoczi } 233761007b31SStefan Hajnoczi 233861007b31SStefan Hajnoczi return rwco.ret; 233961007b31SStefan Hajnoczi } 234061007b31SStefan Hajnoczi 234161007b31SStefan Hajnoczi typedef struct DiscardCo { 234261007b31SStefan Hajnoczi BlockDriverState *bs; 234361007b31SStefan Hajnoczi int64_t sector_num; 234461007b31SStefan Hajnoczi int nb_sectors; 234561007b31SStefan Hajnoczi int ret; 234661007b31SStefan Hajnoczi } DiscardCo; 234761007b31SStefan Hajnoczi static void coroutine_fn bdrv_discard_co_entry(void *opaque) 234861007b31SStefan Hajnoczi { 234961007b31SStefan Hajnoczi DiscardCo *rwco = opaque; 235061007b31SStefan Hajnoczi 235161007b31SStefan Hajnoczi rwco->ret = bdrv_co_discard(rwco->bs, rwco->sector_num, rwco->nb_sectors); 235261007b31SStefan Hajnoczi } 235361007b31SStefan Hajnoczi 235461007b31SStefan Hajnoczi int coroutine_fn bdrv_co_discard(BlockDriverState *bs, int64_t sector_num, 235561007b31SStefan Hajnoczi int nb_sectors) 235661007b31SStefan Hajnoczi { 235761007b31SStefan Hajnoczi int max_discard, ret; 235861007b31SStefan Hajnoczi 235961007b31SStefan Hajnoczi if (!bs->drv) { 236061007b31SStefan Hajnoczi return -ENOMEDIUM; 236161007b31SStefan Hajnoczi } 236261007b31SStefan Hajnoczi 236361007b31SStefan Hajnoczi ret = bdrv_check_request(bs, sector_num, nb_sectors); 236461007b31SStefan Hajnoczi if (ret < 0) { 236561007b31SStefan Hajnoczi return ret; 236661007b31SStefan Hajnoczi } else if (bs->read_only) { 2367eaf5fe2dSPaolo Bonzini return -EPERM; 236861007b31SStefan Hajnoczi } 236961007b31SStefan Hajnoczi 237061007b31SStefan Hajnoczi bdrv_reset_dirty(bs, sector_num, nb_sectors); 237161007b31SStefan Hajnoczi 237261007b31SStefan Hajnoczi /* Do nothing if disabled. */ 237361007b31SStefan Hajnoczi if (!(bs->open_flags & BDRV_O_UNMAP)) { 237461007b31SStefan Hajnoczi return 0; 237561007b31SStefan Hajnoczi } 237661007b31SStefan Hajnoczi 237761007b31SStefan Hajnoczi if (!bs->drv->bdrv_co_discard && !bs->drv->bdrv_aio_discard) { 237861007b31SStefan Hajnoczi return 0; 237961007b31SStefan Hajnoczi } 238061007b31SStefan Hajnoczi 238161007b31SStefan Hajnoczi max_discard = MIN_NON_ZERO(bs->bl.max_discard, BDRV_REQUEST_MAX_SECTORS); 238261007b31SStefan Hajnoczi while (nb_sectors > 0) { 238361007b31SStefan Hajnoczi int ret; 238461007b31SStefan Hajnoczi int num = nb_sectors; 238561007b31SStefan Hajnoczi 238661007b31SStefan Hajnoczi /* align request */ 238761007b31SStefan Hajnoczi if (bs->bl.discard_alignment && 238861007b31SStefan Hajnoczi num >= bs->bl.discard_alignment && 238961007b31SStefan Hajnoczi sector_num % bs->bl.discard_alignment) { 239061007b31SStefan Hajnoczi if (num > bs->bl.discard_alignment) { 239161007b31SStefan Hajnoczi num = bs->bl.discard_alignment; 239261007b31SStefan Hajnoczi } 239361007b31SStefan Hajnoczi num -= sector_num % bs->bl.discard_alignment; 239461007b31SStefan Hajnoczi } 239561007b31SStefan Hajnoczi 239661007b31SStefan Hajnoczi /* limit request size */ 239761007b31SStefan Hajnoczi if (num > max_discard) { 239861007b31SStefan Hajnoczi num = max_discard; 239961007b31SStefan Hajnoczi } 240061007b31SStefan Hajnoczi 240161007b31SStefan Hajnoczi if (bs->drv->bdrv_co_discard) { 240261007b31SStefan Hajnoczi ret = bs->drv->bdrv_co_discard(bs, sector_num, num); 240361007b31SStefan Hajnoczi } else { 240461007b31SStefan Hajnoczi BlockAIOCB *acb; 240561007b31SStefan Hajnoczi CoroutineIOCompletion co = { 240661007b31SStefan Hajnoczi .coroutine = qemu_coroutine_self(), 240761007b31SStefan Hajnoczi }; 240861007b31SStefan Hajnoczi 240961007b31SStefan Hajnoczi acb = bs->drv->bdrv_aio_discard(bs, sector_num, nb_sectors, 241061007b31SStefan Hajnoczi bdrv_co_io_em_complete, &co); 241161007b31SStefan Hajnoczi if (acb == NULL) { 241261007b31SStefan Hajnoczi return -EIO; 241361007b31SStefan Hajnoczi } else { 241461007b31SStefan Hajnoczi qemu_coroutine_yield(); 241561007b31SStefan Hajnoczi ret = co.ret; 241661007b31SStefan Hajnoczi } 241761007b31SStefan Hajnoczi } 241861007b31SStefan Hajnoczi if (ret && ret != -ENOTSUP) { 241961007b31SStefan Hajnoczi return ret; 242061007b31SStefan Hajnoczi } 242161007b31SStefan Hajnoczi 242261007b31SStefan Hajnoczi sector_num += num; 242361007b31SStefan Hajnoczi nb_sectors -= num; 242461007b31SStefan Hajnoczi } 242561007b31SStefan Hajnoczi return 0; 242661007b31SStefan Hajnoczi } 242761007b31SStefan Hajnoczi 242861007b31SStefan Hajnoczi int bdrv_discard(BlockDriverState *bs, int64_t sector_num, int nb_sectors) 242961007b31SStefan Hajnoczi { 243061007b31SStefan Hajnoczi Coroutine *co; 243161007b31SStefan Hajnoczi DiscardCo rwco = { 243261007b31SStefan Hajnoczi .bs = bs, 243361007b31SStefan Hajnoczi .sector_num = sector_num, 243461007b31SStefan Hajnoczi .nb_sectors = nb_sectors, 243561007b31SStefan Hajnoczi .ret = NOT_DONE, 243661007b31SStefan Hajnoczi }; 243761007b31SStefan Hajnoczi 243861007b31SStefan Hajnoczi if (qemu_in_coroutine()) { 243961007b31SStefan Hajnoczi /* Fast-path if already in coroutine context */ 244061007b31SStefan Hajnoczi bdrv_discard_co_entry(&rwco); 244161007b31SStefan Hajnoczi } else { 244261007b31SStefan Hajnoczi AioContext *aio_context = bdrv_get_aio_context(bs); 244361007b31SStefan Hajnoczi 244461007b31SStefan Hajnoczi co = qemu_coroutine_create(bdrv_discard_co_entry); 244561007b31SStefan Hajnoczi qemu_coroutine_enter(co, &rwco); 244661007b31SStefan Hajnoczi while (rwco.ret == NOT_DONE) { 244761007b31SStefan Hajnoczi aio_poll(aio_context, true); 244861007b31SStefan Hajnoczi } 244961007b31SStefan Hajnoczi } 245061007b31SStefan Hajnoczi 245161007b31SStefan Hajnoczi return rwco.ret; 245261007b31SStefan Hajnoczi } 245361007b31SStefan Hajnoczi 245461007b31SStefan Hajnoczi /* needed for generic scsi interface */ 245561007b31SStefan Hajnoczi 245661007b31SStefan Hajnoczi int bdrv_ioctl(BlockDriverState *bs, unsigned long int req, void *buf) 245761007b31SStefan Hajnoczi { 245861007b31SStefan Hajnoczi BlockDriver *drv = bs->drv; 245961007b31SStefan Hajnoczi 246061007b31SStefan Hajnoczi if (drv && drv->bdrv_ioctl) 246161007b31SStefan Hajnoczi return drv->bdrv_ioctl(bs, req, buf); 246261007b31SStefan Hajnoczi return -ENOTSUP; 246361007b31SStefan Hajnoczi } 246461007b31SStefan Hajnoczi 246561007b31SStefan Hajnoczi BlockAIOCB *bdrv_aio_ioctl(BlockDriverState *bs, 246661007b31SStefan Hajnoczi unsigned long int req, void *buf, 246761007b31SStefan Hajnoczi BlockCompletionFunc *cb, void *opaque) 246861007b31SStefan Hajnoczi { 246961007b31SStefan Hajnoczi BlockDriver *drv = bs->drv; 247061007b31SStefan Hajnoczi 247161007b31SStefan Hajnoczi if (drv && drv->bdrv_aio_ioctl) 247261007b31SStefan Hajnoczi return drv->bdrv_aio_ioctl(bs, req, buf, cb, opaque); 247361007b31SStefan Hajnoczi return NULL; 247461007b31SStefan Hajnoczi } 247561007b31SStefan Hajnoczi 247661007b31SStefan Hajnoczi void *qemu_blockalign(BlockDriverState *bs, size_t size) 247761007b31SStefan Hajnoczi { 247861007b31SStefan Hajnoczi return qemu_memalign(bdrv_opt_mem_align(bs), size); 247961007b31SStefan Hajnoczi } 248061007b31SStefan Hajnoczi 248161007b31SStefan Hajnoczi void *qemu_blockalign0(BlockDriverState *bs, size_t size) 248261007b31SStefan Hajnoczi { 248361007b31SStefan Hajnoczi return memset(qemu_blockalign(bs, size), 0, size); 248461007b31SStefan Hajnoczi } 248561007b31SStefan Hajnoczi 248661007b31SStefan Hajnoczi void *qemu_try_blockalign(BlockDriverState *bs, size_t size) 248761007b31SStefan Hajnoczi { 248861007b31SStefan Hajnoczi size_t align = bdrv_opt_mem_align(bs); 248961007b31SStefan Hajnoczi 249061007b31SStefan Hajnoczi /* Ensure that NULL is never returned on success */ 249161007b31SStefan Hajnoczi assert(align > 0); 249261007b31SStefan Hajnoczi if (size == 0) { 249361007b31SStefan Hajnoczi size = align; 249461007b31SStefan Hajnoczi } 249561007b31SStefan Hajnoczi 249661007b31SStefan Hajnoczi return qemu_try_memalign(align, size); 249761007b31SStefan Hajnoczi } 249861007b31SStefan Hajnoczi 249961007b31SStefan Hajnoczi void *qemu_try_blockalign0(BlockDriverState *bs, size_t size) 250061007b31SStefan Hajnoczi { 250161007b31SStefan Hajnoczi void *mem = qemu_try_blockalign(bs, size); 250261007b31SStefan Hajnoczi 250361007b31SStefan Hajnoczi if (mem) { 250461007b31SStefan Hajnoczi memset(mem, 0, size); 250561007b31SStefan Hajnoczi } 250661007b31SStefan Hajnoczi 250761007b31SStefan Hajnoczi return mem; 250861007b31SStefan Hajnoczi } 250961007b31SStefan Hajnoczi 251061007b31SStefan Hajnoczi /* 251161007b31SStefan Hajnoczi * Check if all memory in this vector is sector aligned. 251261007b31SStefan Hajnoczi */ 251361007b31SStefan Hajnoczi bool bdrv_qiov_is_aligned(BlockDriverState *bs, QEMUIOVector *qiov) 251461007b31SStefan Hajnoczi { 251561007b31SStefan Hajnoczi int i; 25164196d2f0SDenis V. Lunev size_t alignment = bdrv_min_mem_align(bs); 251761007b31SStefan Hajnoczi 251861007b31SStefan Hajnoczi for (i = 0; i < qiov->niov; i++) { 251961007b31SStefan Hajnoczi if ((uintptr_t) qiov->iov[i].iov_base % alignment) { 252061007b31SStefan Hajnoczi return false; 252161007b31SStefan Hajnoczi } 252261007b31SStefan Hajnoczi if (qiov->iov[i].iov_len % alignment) { 252361007b31SStefan Hajnoczi return false; 252461007b31SStefan Hajnoczi } 252561007b31SStefan Hajnoczi } 252661007b31SStefan Hajnoczi 252761007b31SStefan Hajnoczi return true; 252861007b31SStefan Hajnoczi } 252961007b31SStefan Hajnoczi 253061007b31SStefan Hajnoczi void bdrv_add_before_write_notifier(BlockDriverState *bs, 253161007b31SStefan Hajnoczi NotifierWithReturn *notifier) 253261007b31SStefan Hajnoczi { 253361007b31SStefan Hajnoczi notifier_with_return_list_add(&bs->before_write_notifiers, notifier); 253461007b31SStefan Hajnoczi } 253561007b31SStefan Hajnoczi 253661007b31SStefan Hajnoczi void bdrv_io_plug(BlockDriverState *bs) 253761007b31SStefan Hajnoczi { 253861007b31SStefan Hajnoczi BlockDriver *drv = bs->drv; 253961007b31SStefan Hajnoczi if (drv && drv->bdrv_io_plug) { 254061007b31SStefan Hajnoczi drv->bdrv_io_plug(bs); 254161007b31SStefan Hajnoczi } else if (bs->file) { 254261007b31SStefan Hajnoczi bdrv_io_plug(bs->file); 254361007b31SStefan Hajnoczi } 254461007b31SStefan Hajnoczi } 254561007b31SStefan Hajnoczi 254661007b31SStefan Hajnoczi void bdrv_io_unplug(BlockDriverState *bs) 254761007b31SStefan Hajnoczi { 254861007b31SStefan Hajnoczi BlockDriver *drv = bs->drv; 254961007b31SStefan Hajnoczi if (drv && drv->bdrv_io_unplug) { 255061007b31SStefan Hajnoczi drv->bdrv_io_unplug(bs); 255161007b31SStefan Hajnoczi } else if (bs->file) { 255261007b31SStefan Hajnoczi bdrv_io_unplug(bs->file); 255361007b31SStefan Hajnoczi } 255461007b31SStefan Hajnoczi } 255561007b31SStefan Hajnoczi 255661007b31SStefan Hajnoczi void bdrv_flush_io_queue(BlockDriverState *bs) 255761007b31SStefan Hajnoczi { 255861007b31SStefan Hajnoczi BlockDriver *drv = bs->drv; 255961007b31SStefan Hajnoczi if (drv && drv->bdrv_flush_io_queue) { 256061007b31SStefan Hajnoczi drv->bdrv_flush_io_queue(bs); 256161007b31SStefan Hajnoczi } else if (bs->file) { 256261007b31SStefan Hajnoczi bdrv_flush_io_queue(bs->file); 256361007b31SStefan Hajnoczi } 256461007b31SStefan Hajnoczi } 2565