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" 2876f4afb4SAlberto Garcia #include "block/throttle-groups.h" 29d49b6836SMarkus Armbruster #include "qemu/error-report.h" 3061007b31SStefan Hajnoczi 3161007b31SStefan Hajnoczi #define NOT_DONE 0x7fffffff /* used while emulated sync operation in progress */ 3261007b31SStefan Hajnoczi 3361007b31SStefan Hajnoczi static BlockAIOCB *bdrv_aio_readv_em(BlockDriverState *bs, 3461007b31SStefan Hajnoczi int64_t sector_num, QEMUIOVector *qiov, int nb_sectors, 3561007b31SStefan Hajnoczi BlockCompletionFunc *cb, void *opaque); 3661007b31SStefan Hajnoczi static BlockAIOCB *bdrv_aio_writev_em(BlockDriverState *bs, 3761007b31SStefan Hajnoczi int64_t sector_num, QEMUIOVector *qiov, int nb_sectors, 3861007b31SStefan Hajnoczi BlockCompletionFunc *cb, void *opaque); 3961007b31SStefan Hajnoczi static int coroutine_fn bdrv_co_readv_em(BlockDriverState *bs, 4061007b31SStefan Hajnoczi int64_t sector_num, int nb_sectors, 4161007b31SStefan Hajnoczi QEMUIOVector *iov); 4261007b31SStefan Hajnoczi static int coroutine_fn bdrv_co_writev_em(BlockDriverState *bs, 4361007b31SStefan Hajnoczi int64_t sector_num, int nb_sectors, 4461007b31SStefan Hajnoczi QEMUIOVector *iov); 4561007b31SStefan Hajnoczi static int coroutine_fn bdrv_co_do_preadv(BlockDriverState *bs, 4661007b31SStefan Hajnoczi int64_t offset, unsigned int bytes, QEMUIOVector *qiov, 4761007b31SStefan Hajnoczi BdrvRequestFlags flags); 4861007b31SStefan Hajnoczi static int coroutine_fn bdrv_co_do_pwritev(BlockDriverState *bs, 4961007b31SStefan Hajnoczi int64_t offset, unsigned int bytes, QEMUIOVector *qiov, 5061007b31SStefan Hajnoczi BdrvRequestFlags flags); 5161007b31SStefan Hajnoczi static BlockAIOCB *bdrv_co_aio_rw_vector(BlockDriverState *bs, 5261007b31SStefan Hajnoczi int64_t sector_num, 5361007b31SStefan Hajnoczi QEMUIOVector *qiov, 5461007b31SStefan Hajnoczi int nb_sectors, 5561007b31SStefan Hajnoczi BdrvRequestFlags flags, 5661007b31SStefan Hajnoczi BlockCompletionFunc *cb, 5761007b31SStefan Hajnoczi void *opaque, 5861007b31SStefan Hajnoczi bool is_write); 5961007b31SStefan Hajnoczi static void coroutine_fn bdrv_co_do_rw(void *opaque); 6061007b31SStefan Hajnoczi static int coroutine_fn bdrv_co_do_write_zeroes(BlockDriverState *bs, 6161007b31SStefan Hajnoczi int64_t sector_num, int nb_sectors, BdrvRequestFlags flags); 6261007b31SStefan Hajnoczi 6361007b31SStefan Hajnoczi /* throttling disk I/O limits */ 6461007b31SStefan Hajnoczi void bdrv_set_io_limits(BlockDriverState *bs, 6561007b31SStefan Hajnoczi ThrottleConfig *cfg) 6661007b31SStefan Hajnoczi { 6761007b31SStefan Hajnoczi int i; 6861007b31SStefan Hajnoczi 6976f4afb4SAlberto Garcia throttle_group_config(bs, cfg); 7061007b31SStefan Hajnoczi 7161007b31SStefan Hajnoczi for (i = 0; i < 2; i++) { 7261007b31SStefan Hajnoczi qemu_co_enter_next(&bs->throttled_reqs[i]); 7361007b31SStefan Hajnoczi } 7461007b31SStefan Hajnoczi } 7561007b31SStefan Hajnoczi 7661007b31SStefan Hajnoczi /* this function drain all the throttled IOs */ 7761007b31SStefan Hajnoczi static bool bdrv_start_throttled_reqs(BlockDriverState *bs) 7861007b31SStefan Hajnoczi { 7961007b31SStefan Hajnoczi bool drained = false; 8061007b31SStefan Hajnoczi bool enabled = bs->io_limits_enabled; 8161007b31SStefan Hajnoczi int i; 8261007b31SStefan Hajnoczi 8361007b31SStefan Hajnoczi bs->io_limits_enabled = false; 8461007b31SStefan Hajnoczi 8561007b31SStefan Hajnoczi for (i = 0; i < 2; i++) { 8661007b31SStefan Hajnoczi while (qemu_co_enter_next(&bs->throttled_reqs[i])) { 8761007b31SStefan Hajnoczi drained = true; 8861007b31SStefan Hajnoczi } 8961007b31SStefan Hajnoczi } 9061007b31SStefan Hajnoczi 9161007b31SStefan Hajnoczi bs->io_limits_enabled = enabled; 9261007b31SStefan Hajnoczi 9361007b31SStefan Hajnoczi return drained; 9461007b31SStefan Hajnoczi } 9561007b31SStefan Hajnoczi 9661007b31SStefan Hajnoczi void bdrv_io_limits_disable(BlockDriverState *bs) 9761007b31SStefan Hajnoczi { 9861007b31SStefan Hajnoczi bs->io_limits_enabled = false; 9961007b31SStefan Hajnoczi bdrv_start_throttled_reqs(bs); 10076f4afb4SAlberto Garcia throttle_group_unregister_bs(bs); 10161007b31SStefan Hajnoczi } 10261007b31SStefan Hajnoczi 10361007b31SStefan Hajnoczi /* should be called before bdrv_set_io_limits if a limit is set */ 10476f4afb4SAlberto Garcia void bdrv_io_limits_enable(BlockDriverState *bs, const char *group) 10561007b31SStefan Hajnoczi { 10661007b31SStefan Hajnoczi assert(!bs->io_limits_enabled); 10776f4afb4SAlberto Garcia throttle_group_register_bs(bs, group); 10861007b31SStefan Hajnoczi bs->io_limits_enabled = true; 10961007b31SStefan Hajnoczi } 11061007b31SStefan Hajnoczi 11176f4afb4SAlberto Garcia void bdrv_io_limits_update_group(BlockDriverState *bs, const char *group) 11261007b31SStefan Hajnoczi { 11376f4afb4SAlberto Garcia /* this bs is not part of any group */ 11476f4afb4SAlberto Garcia if (!bs->throttle_state) { 11561007b31SStefan Hajnoczi return; 11661007b31SStefan Hajnoczi } 11761007b31SStefan Hajnoczi 11876f4afb4SAlberto Garcia /* this bs is a part of the same group than the one we want */ 11976f4afb4SAlberto Garcia if (!g_strcmp0(throttle_group_get_name(bs), group)) { 12076f4afb4SAlberto Garcia return; 12176f4afb4SAlberto Garcia } 12276f4afb4SAlberto Garcia 12376f4afb4SAlberto Garcia /* need to change the group this bs belong to */ 12476f4afb4SAlberto Garcia bdrv_io_limits_disable(bs); 12576f4afb4SAlberto Garcia bdrv_io_limits_enable(bs, group); 12661007b31SStefan Hajnoczi } 12761007b31SStefan Hajnoczi 12861007b31SStefan Hajnoczi void bdrv_setup_io_funcs(BlockDriver *bdrv) 12961007b31SStefan Hajnoczi { 13061007b31SStefan Hajnoczi /* Block drivers without coroutine functions need emulation */ 13161007b31SStefan Hajnoczi if (!bdrv->bdrv_co_readv) { 13261007b31SStefan Hajnoczi bdrv->bdrv_co_readv = bdrv_co_readv_em; 13361007b31SStefan Hajnoczi bdrv->bdrv_co_writev = bdrv_co_writev_em; 13461007b31SStefan Hajnoczi 13561007b31SStefan Hajnoczi /* bdrv_co_readv_em()/brdv_co_writev_em() work in terms of aio, so if 13661007b31SStefan Hajnoczi * the block driver lacks aio we need to emulate that too. 13761007b31SStefan Hajnoczi */ 13861007b31SStefan Hajnoczi if (!bdrv->bdrv_aio_readv) { 13961007b31SStefan Hajnoczi /* add AIO emulation layer */ 14061007b31SStefan Hajnoczi bdrv->bdrv_aio_readv = bdrv_aio_readv_em; 14161007b31SStefan Hajnoczi bdrv->bdrv_aio_writev = bdrv_aio_writev_em; 14261007b31SStefan Hajnoczi } 14361007b31SStefan Hajnoczi } 14461007b31SStefan Hajnoczi } 14561007b31SStefan Hajnoczi 14661007b31SStefan Hajnoczi void bdrv_refresh_limits(BlockDriverState *bs, Error **errp) 14761007b31SStefan Hajnoczi { 14861007b31SStefan Hajnoczi BlockDriver *drv = bs->drv; 14961007b31SStefan Hajnoczi Error *local_err = NULL; 15061007b31SStefan Hajnoczi 15161007b31SStefan Hajnoczi memset(&bs->bl, 0, sizeof(bs->bl)); 15261007b31SStefan Hajnoczi 15361007b31SStefan Hajnoczi if (!drv) { 15461007b31SStefan Hajnoczi return; 15561007b31SStefan Hajnoczi } 15661007b31SStefan Hajnoczi 15761007b31SStefan Hajnoczi /* Take some limits from the children as a default */ 15861007b31SStefan Hajnoczi if (bs->file) { 1599a4f4c31SKevin Wolf bdrv_refresh_limits(bs->file->bs, &local_err); 16061007b31SStefan Hajnoczi if (local_err) { 16161007b31SStefan Hajnoczi error_propagate(errp, local_err); 16261007b31SStefan Hajnoczi return; 16361007b31SStefan Hajnoczi } 1649a4f4c31SKevin Wolf bs->bl.opt_transfer_length = bs->file->bs->bl.opt_transfer_length; 1659a4f4c31SKevin Wolf bs->bl.max_transfer_length = bs->file->bs->bl.max_transfer_length; 1669a4f4c31SKevin Wolf bs->bl.min_mem_alignment = bs->file->bs->bl.min_mem_alignment; 1679a4f4c31SKevin Wolf bs->bl.opt_mem_alignment = bs->file->bs->bl.opt_mem_alignment; 16861007b31SStefan Hajnoczi } else { 1694196d2f0SDenis V. Lunev bs->bl.min_mem_alignment = 512; 170459b4e66SDenis V. Lunev bs->bl.opt_mem_alignment = getpagesize(); 17161007b31SStefan Hajnoczi } 17261007b31SStefan Hajnoczi 173760e0063SKevin Wolf if (bs->backing) { 174760e0063SKevin Wolf bdrv_refresh_limits(bs->backing->bs, &local_err); 17561007b31SStefan Hajnoczi if (local_err) { 17661007b31SStefan Hajnoczi error_propagate(errp, local_err); 17761007b31SStefan Hajnoczi return; 17861007b31SStefan Hajnoczi } 17961007b31SStefan Hajnoczi bs->bl.opt_transfer_length = 18061007b31SStefan Hajnoczi MAX(bs->bl.opt_transfer_length, 181760e0063SKevin Wolf bs->backing->bs->bl.opt_transfer_length); 18261007b31SStefan Hajnoczi bs->bl.max_transfer_length = 18361007b31SStefan Hajnoczi MIN_NON_ZERO(bs->bl.max_transfer_length, 184760e0063SKevin Wolf bs->backing->bs->bl.max_transfer_length); 18561007b31SStefan Hajnoczi bs->bl.opt_mem_alignment = 18661007b31SStefan Hajnoczi MAX(bs->bl.opt_mem_alignment, 187760e0063SKevin Wolf bs->backing->bs->bl.opt_mem_alignment); 1884196d2f0SDenis V. Lunev bs->bl.min_mem_alignment = 1894196d2f0SDenis V. Lunev MAX(bs->bl.min_mem_alignment, 190760e0063SKevin Wolf bs->backing->bs->bl.min_mem_alignment); 19161007b31SStefan Hajnoczi } 19261007b31SStefan Hajnoczi 19361007b31SStefan Hajnoczi /* Then let the driver override it */ 19461007b31SStefan Hajnoczi if (drv->bdrv_refresh_limits) { 19561007b31SStefan Hajnoczi drv->bdrv_refresh_limits(bs, errp); 19661007b31SStefan Hajnoczi } 19761007b31SStefan Hajnoczi } 19861007b31SStefan Hajnoczi 19961007b31SStefan Hajnoczi /** 20061007b31SStefan Hajnoczi * The copy-on-read flag is actually a reference count so multiple users may 20161007b31SStefan Hajnoczi * use the feature without worrying about clobbering its previous state. 20261007b31SStefan Hajnoczi * Copy-on-read stays enabled until all users have called to disable it. 20361007b31SStefan Hajnoczi */ 20461007b31SStefan Hajnoczi void bdrv_enable_copy_on_read(BlockDriverState *bs) 20561007b31SStefan Hajnoczi { 20661007b31SStefan Hajnoczi bs->copy_on_read++; 20761007b31SStefan Hajnoczi } 20861007b31SStefan Hajnoczi 20961007b31SStefan Hajnoczi void bdrv_disable_copy_on_read(BlockDriverState *bs) 21061007b31SStefan Hajnoczi { 21161007b31SStefan Hajnoczi assert(bs->copy_on_read > 0); 21261007b31SStefan Hajnoczi bs->copy_on_read--; 21361007b31SStefan Hajnoczi } 21461007b31SStefan Hajnoczi 21561007b31SStefan Hajnoczi /* Check if any requests are in-flight (including throttled requests) */ 216439db28cSKevin Wolf bool bdrv_requests_pending(BlockDriverState *bs) 21761007b31SStefan Hajnoczi { 21861007b31SStefan Hajnoczi if (!QLIST_EMPTY(&bs->tracked_requests)) { 21961007b31SStefan Hajnoczi return true; 22061007b31SStefan Hajnoczi } 22161007b31SStefan Hajnoczi if (!qemu_co_queue_empty(&bs->throttled_reqs[0])) { 22261007b31SStefan Hajnoczi return true; 22361007b31SStefan Hajnoczi } 22461007b31SStefan Hajnoczi if (!qemu_co_queue_empty(&bs->throttled_reqs[1])) { 22561007b31SStefan Hajnoczi return true; 22661007b31SStefan Hajnoczi } 2279a4f4c31SKevin Wolf if (bs->file && bdrv_requests_pending(bs->file->bs)) { 22861007b31SStefan Hajnoczi return true; 22961007b31SStefan Hajnoczi } 230760e0063SKevin Wolf if (bs->backing && bdrv_requests_pending(bs->backing->bs)) { 23161007b31SStefan Hajnoczi return true; 23261007b31SStefan Hajnoczi } 23361007b31SStefan Hajnoczi return false; 23461007b31SStefan Hajnoczi } 23561007b31SStefan Hajnoczi 23661007b31SStefan Hajnoczi /* 23761007b31SStefan Hajnoczi * Wait for pending requests to complete on a single BlockDriverState subtree 23861007b31SStefan Hajnoczi * 23961007b31SStefan Hajnoczi * Note that unlike bdrv_drain_all(), the caller must hold the BlockDriverState 24061007b31SStefan Hajnoczi * AioContext. 2417a63f3cdSStefan Hajnoczi * 2427a63f3cdSStefan Hajnoczi * Only this BlockDriverState's AioContext is run, so in-flight requests must 2437a63f3cdSStefan Hajnoczi * not depend on events in other AioContexts. In that case, use 2447a63f3cdSStefan Hajnoczi * bdrv_drain_all() instead. 24561007b31SStefan Hajnoczi */ 24661007b31SStefan Hajnoczi void bdrv_drain(BlockDriverState *bs) 24761007b31SStefan Hajnoczi { 248f406c03cSAlexander Yarygin bool busy = true; 249f406c03cSAlexander Yarygin 250f406c03cSAlexander Yarygin while (busy) { 25161007b31SStefan Hajnoczi /* Keep iterating */ 252f406c03cSAlexander Yarygin bdrv_flush_io_queue(bs); 253f406c03cSAlexander Yarygin busy = bdrv_requests_pending(bs); 254f406c03cSAlexander Yarygin busy |= aio_poll(bdrv_get_aio_context(bs), busy); 25561007b31SStefan Hajnoczi } 25661007b31SStefan Hajnoczi } 25761007b31SStefan Hajnoczi 25861007b31SStefan Hajnoczi /* 25961007b31SStefan Hajnoczi * Wait for pending requests to complete across all BlockDriverStates 26061007b31SStefan Hajnoczi * 26161007b31SStefan Hajnoczi * This function does not flush data to disk, use bdrv_flush_all() for that 26261007b31SStefan Hajnoczi * after calling this function. 26361007b31SStefan Hajnoczi */ 26461007b31SStefan Hajnoczi void bdrv_drain_all(void) 26561007b31SStefan Hajnoczi { 26661007b31SStefan Hajnoczi /* Always run first iteration so any pending completion BHs run */ 26761007b31SStefan Hajnoczi bool busy = true; 26861007b31SStefan Hajnoczi BlockDriverState *bs = NULL; 269f406c03cSAlexander Yarygin GSList *aio_ctxs = NULL, *ctx; 27061007b31SStefan Hajnoczi 27161007b31SStefan Hajnoczi while ((bs = bdrv_next(bs))) { 27261007b31SStefan Hajnoczi AioContext *aio_context = bdrv_get_aio_context(bs); 27361007b31SStefan Hajnoczi 27461007b31SStefan Hajnoczi aio_context_acquire(aio_context); 27561007b31SStefan Hajnoczi if (bs->job) { 27661007b31SStefan Hajnoczi block_job_pause(bs->job); 27761007b31SStefan Hajnoczi } 27861007b31SStefan Hajnoczi aio_context_release(aio_context); 279f406c03cSAlexander Yarygin 280764ba3aeSAlberto Garcia if (!g_slist_find(aio_ctxs, aio_context)) { 281f406c03cSAlexander Yarygin aio_ctxs = g_slist_prepend(aio_ctxs, aio_context); 282f406c03cSAlexander Yarygin } 28361007b31SStefan Hajnoczi } 28461007b31SStefan Hajnoczi 2857a63f3cdSStefan Hajnoczi /* Note that completion of an asynchronous I/O operation can trigger any 2867a63f3cdSStefan Hajnoczi * number of other I/O operations on other devices---for example a 2877a63f3cdSStefan Hajnoczi * coroutine can submit an I/O request to another device in response to 2887a63f3cdSStefan Hajnoczi * request completion. Therefore we must keep looping until there was no 2897a63f3cdSStefan Hajnoczi * more activity rather than simply draining each device independently. 2907a63f3cdSStefan Hajnoczi */ 29161007b31SStefan Hajnoczi while (busy) { 29261007b31SStefan Hajnoczi busy = false; 293f406c03cSAlexander Yarygin 294f406c03cSAlexander Yarygin for (ctx = aio_ctxs; ctx != NULL; ctx = ctx->next) { 295f406c03cSAlexander Yarygin AioContext *aio_context = ctx->data; 29661007b31SStefan Hajnoczi bs = NULL; 29761007b31SStefan Hajnoczi 29861007b31SStefan Hajnoczi aio_context_acquire(aio_context); 299f406c03cSAlexander Yarygin while ((bs = bdrv_next(bs))) { 300f406c03cSAlexander Yarygin if (aio_context == bdrv_get_aio_context(bs)) { 301f406c03cSAlexander Yarygin bdrv_flush_io_queue(bs); 302f406c03cSAlexander Yarygin if (bdrv_requests_pending(bs)) { 303f406c03cSAlexander Yarygin busy = true; 304f406c03cSAlexander Yarygin aio_poll(aio_context, busy); 305f406c03cSAlexander Yarygin } 306f406c03cSAlexander Yarygin } 307f406c03cSAlexander Yarygin } 308f406c03cSAlexander Yarygin busy |= aio_poll(aio_context, false); 30961007b31SStefan Hajnoczi aio_context_release(aio_context); 31061007b31SStefan Hajnoczi } 31161007b31SStefan Hajnoczi } 31261007b31SStefan Hajnoczi 31361007b31SStefan Hajnoczi bs = NULL; 31461007b31SStefan Hajnoczi while ((bs = bdrv_next(bs))) { 31561007b31SStefan Hajnoczi AioContext *aio_context = bdrv_get_aio_context(bs); 31661007b31SStefan Hajnoczi 31761007b31SStefan Hajnoczi aio_context_acquire(aio_context); 31861007b31SStefan Hajnoczi if (bs->job) { 31961007b31SStefan Hajnoczi block_job_resume(bs->job); 32061007b31SStefan Hajnoczi } 32161007b31SStefan Hajnoczi aio_context_release(aio_context); 32261007b31SStefan Hajnoczi } 323f406c03cSAlexander Yarygin g_slist_free(aio_ctxs); 32461007b31SStefan Hajnoczi } 32561007b31SStefan Hajnoczi 32661007b31SStefan Hajnoczi /** 32761007b31SStefan Hajnoczi * Remove an active request from the tracked requests list 32861007b31SStefan Hajnoczi * 32961007b31SStefan Hajnoczi * This function should be called when a tracked request is completing. 33061007b31SStefan Hajnoczi */ 33161007b31SStefan Hajnoczi static void tracked_request_end(BdrvTrackedRequest *req) 33261007b31SStefan Hajnoczi { 33361007b31SStefan Hajnoczi if (req->serialising) { 33461007b31SStefan Hajnoczi req->bs->serialising_in_flight--; 33561007b31SStefan Hajnoczi } 33661007b31SStefan Hajnoczi 33761007b31SStefan Hajnoczi QLIST_REMOVE(req, list); 33861007b31SStefan Hajnoczi qemu_co_queue_restart_all(&req->wait_queue); 33961007b31SStefan Hajnoczi } 34061007b31SStefan Hajnoczi 34161007b31SStefan Hajnoczi /** 34261007b31SStefan Hajnoczi * Add an active request to the tracked requests list 34361007b31SStefan Hajnoczi */ 34461007b31SStefan Hajnoczi static void tracked_request_begin(BdrvTrackedRequest *req, 34561007b31SStefan Hajnoczi BlockDriverState *bs, 34661007b31SStefan Hajnoczi int64_t offset, 34761007b31SStefan Hajnoczi unsigned int bytes, bool is_write) 34861007b31SStefan Hajnoczi { 34961007b31SStefan Hajnoczi *req = (BdrvTrackedRequest){ 35061007b31SStefan Hajnoczi .bs = bs, 35161007b31SStefan Hajnoczi .offset = offset, 35261007b31SStefan Hajnoczi .bytes = bytes, 35361007b31SStefan Hajnoczi .is_write = is_write, 35461007b31SStefan Hajnoczi .co = qemu_coroutine_self(), 35561007b31SStefan Hajnoczi .serialising = false, 35661007b31SStefan Hajnoczi .overlap_offset = offset, 35761007b31SStefan Hajnoczi .overlap_bytes = bytes, 35861007b31SStefan Hajnoczi }; 35961007b31SStefan Hajnoczi 36061007b31SStefan Hajnoczi qemu_co_queue_init(&req->wait_queue); 36161007b31SStefan Hajnoczi 36261007b31SStefan Hajnoczi QLIST_INSERT_HEAD(&bs->tracked_requests, req, list); 36361007b31SStefan Hajnoczi } 36461007b31SStefan Hajnoczi 36561007b31SStefan Hajnoczi static void mark_request_serialising(BdrvTrackedRequest *req, uint64_t align) 36661007b31SStefan Hajnoczi { 36761007b31SStefan Hajnoczi int64_t overlap_offset = req->offset & ~(align - 1); 36861007b31SStefan Hajnoczi unsigned int overlap_bytes = ROUND_UP(req->offset + req->bytes, align) 36961007b31SStefan Hajnoczi - overlap_offset; 37061007b31SStefan Hajnoczi 37161007b31SStefan Hajnoczi if (!req->serialising) { 37261007b31SStefan Hajnoczi req->bs->serialising_in_flight++; 37361007b31SStefan Hajnoczi req->serialising = true; 37461007b31SStefan Hajnoczi } 37561007b31SStefan Hajnoczi 37661007b31SStefan Hajnoczi req->overlap_offset = MIN(req->overlap_offset, overlap_offset); 37761007b31SStefan Hajnoczi req->overlap_bytes = MAX(req->overlap_bytes, overlap_bytes); 37861007b31SStefan Hajnoczi } 37961007b31SStefan Hajnoczi 38061007b31SStefan Hajnoczi /** 38161007b31SStefan Hajnoczi * Round a region to cluster boundaries 38261007b31SStefan Hajnoczi */ 38361007b31SStefan Hajnoczi void bdrv_round_to_clusters(BlockDriverState *bs, 38461007b31SStefan Hajnoczi int64_t sector_num, int nb_sectors, 38561007b31SStefan Hajnoczi int64_t *cluster_sector_num, 38661007b31SStefan Hajnoczi int *cluster_nb_sectors) 38761007b31SStefan Hajnoczi { 38861007b31SStefan Hajnoczi BlockDriverInfo bdi; 38961007b31SStefan Hajnoczi 39061007b31SStefan Hajnoczi if (bdrv_get_info(bs, &bdi) < 0 || bdi.cluster_size == 0) { 39161007b31SStefan Hajnoczi *cluster_sector_num = sector_num; 39261007b31SStefan Hajnoczi *cluster_nb_sectors = nb_sectors; 39361007b31SStefan Hajnoczi } else { 39461007b31SStefan Hajnoczi int64_t c = bdi.cluster_size / BDRV_SECTOR_SIZE; 39561007b31SStefan Hajnoczi *cluster_sector_num = QEMU_ALIGN_DOWN(sector_num, c); 39661007b31SStefan Hajnoczi *cluster_nb_sectors = QEMU_ALIGN_UP(sector_num - *cluster_sector_num + 39761007b31SStefan Hajnoczi nb_sectors, c); 39861007b31SStefan Hajnoczi } 39961007b31SStefan Hajnoczi } 40061007b31SStefan Hajnoczi 40161007b31SStefan Hajnoczi static int bdrv_get_cluster_size(BlockDriverState *bs) 40261007b31SStefan Hajnoczi { 40361007b31SStefan Hajnoczi BlockDriverInfo bdi; 40461007b31SStefan Hajnoczi int ret; 40561007b31SStefan Hajnoczi 40661007b31SStefan Hajnoczi ret = bdrv_get_info(bs, &bdi); 40761007b31SStefan Hajnoczi if (ret < 0 || bdi.cluster_size == 0) { 40861007b31SStefan Hajnoczi return bs->request_alignment; 40961007b31SStefan Hajnoczi } else { 41061007b31SStefan Hajnoczi return bdi.cluster_size; 41161007b31SStefan Hajnoczi } 41261007b31SStefan Hajnoczi } 41361007b31SStefan Hajnoczi 41461007b31SStefan Hajnoczi static bool tracked_request_overlaps(BdrvTrackedRequest *req, 41561007b31SStefan Hajnoczi int64_t offset, unsigned int bytes) 41661007b31SStefan Hajnoczi { 41761007b31SStefan Hajnoczi /* aaaa bbbb */ 41861007b31SStefan Hajnoczi if (offset >= req->overlap_offset + req->overlap_bytes) { 41961007b31SStefan Hajnoczi return false; 42061007b31SStefan Hajnoczi } 42161007b31SStefan Hajnoczi /* bbbb aaaa */ 42261007b31SStefan Hajnoczi if (req->overlap_offset >= offset + bytes) { 42361007b31SStefan Hajnoczi return false; 42461007b31SStefan Hajnoczi } 42561007b31SStefan Hajnoczi return true; 42661007b31SStefan Hajnoczi } 42761007b31SStefan Hajnoczi 42861007b31SStefan Hajnoczi static bool coroutine_fn wait_serialising_requests(BdrvTrackedRequest *self) 42961007b31SStefan Hajnoczi { 43061007b31SStefan Hajnoczi BlockDriverState *bs = self->bs; 43161007b31SStefan Hajnoczi BdrvTrackedRequest *req; 43261007b31SStefan Hajnoczi bool retry; 43361007b31SStefan Hajnoczi bool waited = false; 43461007b31SStefan Hajnoczi 43561007b31SStefan Hajnoczi if (!bs->serialising_in_flight) { 43661007b31SStefan Hajnoczi return false; 43761007b31SStefan Hajnoczi } 43861007b31SStefan Hajnoczi 43961007b31SStefan Hajnoczi do { 44061007b31SStefan Hajnoczi retry = false; 44161007b31SStefan Hajnoczi QLIST_FOREACH(req, &bs->tracked_requests, list) { 44261007b31SStefan Hajnoczi if (req == self || (!req->serialising && !self->serialising)) { 44361007b31SStefan Hajnoczi continue; 44461007b31SStefan Hajnoczi } 44561007b31SStefan Hajnoczi if (tracked_request_overlaps(req, self->overlap_offset, 44661007b31SStefan Hajnoczi self->overlap_bytes)) 44761007b31SStefan Hajnoczi { 44861007b31SStefan Hajnoczi /* Hitting this means there was a reentrant request, for 44961007b31SStefan Hajnoczi * example, a block driver issuing nested requests. This must 45061007b31SStefan Hajnoczi * never happen since it means deadlock. 45161007b31SStefan Hajnoczi */ 45261007b31SStefan Hajnoczi assert(qemu_coroutine_self() != req->co); 45361007b31SStefan Hajnoczi 45461007b31SStefan Hajnoczi /* If the request is already (indirectly) waiting for us, or 45561007b31SStefan Hajnoczi * will wait for us as soon as it wakes up, then just go on 45661007b31SStefan Hajnoczi * (instead of producing a deadlock in the former case). */ 45761007b31SStefan Hajnoczi if (!req->waiting_for) { 45861007b31SStefan Hajnoczi self->waiting_for = req; 45961007b31SStefan Hajnoczi qemu_co_queue_wait(&req->wait_queue); 46061007b31SStefan Hajnoczi self->waiting_for = NULL; 46161007b31SStefan Hajnoczi retry = true; 46261007b31SStefan Hajnoczi waited = true; 46361007b31SStefan Hajnoczi break; 46461007b31SStefan Hajnoczi } 46561007b31SStefan Hajnoczi } 46661007b31SStefan Hajnoczi } 46761007b31SStefan Hajnoczi } while (retry); 46861007b31SStefan Hajnoczi 46961007b31SStefan Hajnoczi return waited; 47061007b31SStefan Hajnoczi } 47161007b31SStefan Hajnoczi 47261007b31SStefan Hajnoczi static int bdrv_check_byte_request(BlockDriverState *bs, int64_t offset, 47361007b31SStefan Hajnoczi size_t size) 47461007b31SStefan Hajnoczi { 47561007b31SStefan Hajnoczi if (size > BDRV_REQUEST_MAX_SECTORS << BDRV_SECTOR_BITS) { 47661007b31SStefan Hajnoczi return -EIO; 47761007b31SStefan Hajnoczi } 47861007b31SStefan Hajnoczi 47961007b31SStefan Hajnoczi if (!bdrv_is_inserted(bs)) { 48061007b31SStefan Hajnoczi return -ENOMEDIUM; 48161007b31SStefan Hajnoczi } 48261007b31SStefan Hajnoczi 48361007b31SStefan Hajnoczi if (offset < 0) { 48461007b31SStefan Hajnoczi return -EIO; 48561007b31SStefan Hajnoczi } 48661007b31SStefan Hajnoczi 48761007b31SStefan Hajnoczi return 0; 48861007b31SStefan Hajnoczi } 48961007b31SStefan Hajnoczi 49061007b31SStefan Hajnoczi static int bdrv_check_request(BlockDriverState *bs, int64_t sector_num, 49161007b31SStefan Hajnoczi int nb_sectors) 49261007b31SStefan Hajnoczi { 49361007b31SStefan Hajnoczi if (nb_sectors < 0 || nb_sectors > BDRV_REQUEST_MAX_SECTORS) { 49461007b31SStefan Hajnoczi return -EIO; 49561007b31SStefan Hajnoczi } 49661007b31SStefan Hajnoczi 49761007b31SStefan Hajnoczi return bdrv_check_byte_request(bs, sector_num * BDRV_SECTOR_SIZE, 49861007b31SStefan Hajnoczi nb_sectors * BDRV_SECTOR_SIZE); 49961007b31SStefan Hajnoczi } 50061007b31SStefan Hajnoczi 50161007b31SStefan Hajnoczi typedef struct RwCo { 50261007b31SStefan Hajnoczi BlockDriverState *bs; 50361007b31SStefan Hajnoczi int64_t offset; 50461007b31SStefan Hajnoczi QEMUIOVector *qiov; 50561007b31SStefan Hajnoczi bool is_write; 50661007b31SStefan Hajnoczi int ret; 50761007b31SStefan Hajnoczi BdrvRequestFlags flags; 50861007b31SStefan Hajnoczi } RwCo; 50961007b31SStefan Hajnoczi 51061007b31SStefan Hajnoczi static void coroutine_fn bdrv_rw_co_entry(void *opaque) 51161007b31SStefan Hajnoczi { 51261007b31SStefan Hajnoczi RwCo *rwco = opaque; 51361007b31SStefan Hajnoczi 51461007b31SStefan Hajnoczi if (!rwco->is_write) { 51561007b31SStefan Hajnoczi rwco->ret = bdrv_co_do_preadv(rwco->bs, rwco->offset, 51661007b31SStefan Hajnoczi rwco->qiov->size, rwco->qiov, 51761007b31SStefan Hajnoczi rwco->flags); 51861007b31SStefan Hajnoczi } else { 51961007b31SStefan Hajnoczi rwco->ret = bdrv_co_do_pwritev(rwco->bs, rwco->offset, 52061007b31SStefan Hajnoczi rwco->qiov->size, rwco->qiov, 52161007b31SStefan Hajnoczi rwco->flags); 52261007b31SStefan Hajnoczi } 52361007b31SStefan Hajnoczi } 52461007b31SStefan Hajnoczi 52561007b31SStefan Hajnoczi /* 52661007b31SStefan Hajnoczi * Process a vectored synchronous request using coroutines 52761007b31SStefan Hajnoczi */ 52861007b31SStefan Hajnoczi static int bdrv_prwv_co(BlockDriverState *bs, int64_t offset, 52961007b31SStefan Hajnoczi QEMUIOVector *qiov, bool is_write, 53061007b31SStefan Hajnoczi BdrvRequestFlags flags) 53161007b31SStefan Hajnoczi { 53261007b31SStefan Hajnoczi Coroutine *co; 53361007b31SStefan Hajnoczi RwCo rwco = { 53461007b31SStefan Hajnoczi .bs = bs, 53561007b31SStefan Hajnoczi .offset = offset, 53661007b31SStefan Hajnoczi .qiov = qiov, 53761007b31SStefan Hajnoczi .is_write = is_write, 53861007b31SStefan Hajnoczi .ret = NOT_DONE, 53961007b31SStefan Hajnoczi .flags = flags, 54061007b31SStefan Hajnoczi }; 54161007b31SStefan Hajnoczi 54261007b31SStefan Hajnoczi /** 54361007b31SStefan Hajnoczi * In sync call context, when the vcpu is blocked, this throttling timer 54461007b31SStefan Hajnoczi * will not fire; so the I/O throttling function has to be disabled here 54561007b31SStefan Hajnoczi * if it has been enabled. 54661007b31SStefan Hajnoczi */ 54761007b31SStefan Hajnoczi if (bs->io_limits_enabled) { 54861007b31SStefan Hajnoczi fprintf(stderr, "Disabling I/O throttling on '%s' due " 54961007b31SStefan Hajnoczi "to synchronous I/O.\n", bdrv_get_device_name(bs)); 55061007b31SStefan Hajnoczi bdrv_io_limits_disable(bs); 55161007b31SStefan Hajnoczi } 55261007b31SStefan Hajnoczi 55361007b31SStefan Hajnoczi if (qemu_in_coroutine()) { 55461007b31SStefan Hajnoczi /* Fast-path if already in coroutine context */ 55561007b31SStefan Hajnoczi bdrv_rw_co_entry(&rwco); 55661007b31SStefan Hajnoczi } else { 55761007b31SStefan Hajnoczi AioContext *aio_context = bdrv_get_aio_context(bs); 55861007b31SStefan Hajnoczi 55961007b31SStefan Hajnoczi co = qemu_coroutine_create(bdrv_rw_co_entry); 56061007b31SStefan Hajnoczi qemu_coroutine_enter(co, &rwco); 56161007b31SStefan Hajnoczi while (rwco.ret == NOT_DONE) { 56261007b31SStefan Hajnoczi aio_poll(aio_context, true); 56361007b31SStefan Hajnoczi } 56461007b31SStefan Hajnoczi } 56561007b31SStefan Hajnoczi return rwco.ret; 56661007b31SStefan Hajnoczi } 56761007b31SStefan Hajnoczi 56861007b31SStefan Hajnoczi /* 56961007b31SStefan Hajnoczi * Process a synchronous request using coroutines 57061007b31SStefan Hajnoczi */ 57161007b31SStefan Hajnoczi static int bdrv_rw_co(BlockDriverState *bs, int64_t sector_num, uint8_t *buf, 57261007b31SStefan Hajnoczi int nb_sectors, bool is_write, BdrvRequestFlags flags) 57361007b31SStefan Hajnoczi { 57461007b31SStefan Hajnoczi QEMUIOVector qiov; 57561007b31SStefan Hajnoczi struct iovec iov = { 57661007b31SStefan Hajnoczi .iov_base = (void *)buf, 57761007b31SStefan Hajnoczi .iov_len = nb_sectors * BDRV_SECTOR_SIZE, 57861007b31SStefan Hajnoczi }; 57961007b31SStefan Hajnoczi 58061007b31SStefan Hajnoczi if (nb_sectors < 0 || nb_sectors > BDRV_REQUEST_MAX_SECTORS) { 58161007b31SStefan Hajnoczi return -EINVAL; 58261007b31SStefan Hajnoczi } 58361007b31SStefan Hajnoczi 58461007b31SStefan Hajnoczi qemu_iovec_init_external(&qiov, &iov, 1); 58561007b31SStefan Hajnoczi return bdrv_prwv_co(bs, sector_num << BDRV_SECTOR_BITS, 58661007b31SStefan Hajnoczi &qiov, is_write, flags); 58761007b31SStefan Hajnoczi } 58861007b31SStefan Hajnoczi 58961007b31SStefan Hajnoczi /* return < 0 if error. See bdrv_write() for the return codes */ 59061007b31SStefan Hajnoczi int bdrv_read(BlockDriverState *bs, int64_t sector_num, 59161007b31SStefan Hajnoczi uint8_t *buf, int nb_sectors) 59261007b31SStefan Hajnoczi { 59361007b31SStefan Hajnoczi return bdrv_rw_co(bs, sector_num, buf, nb_sectors, false, 0); 59461007b31SStefan Hajnoczi } 59561007b31SStefan Hajnoczi 59661007b31SStefan Hajnoczi /* Just like bdrv_read(), but with I/O throttling temporarily disabled */ 59761007b31SStefan Hajnoczi int bdrv_read_unthrottled(BlockDriverState *bs, int64_t sector_num, 59861007b31SStefan Hajnoczi uint8_t *buf, int nb_sectors) 59961007b31SStefan Hajnoczi { 60061007b31SStefan Hajnoczi bool enabled; 60161007b31SStefan Hajnoczi int ret; 60261007b31SStefan Hajnoczi 60361007b31SStefan Hajnoczi enabled = bs->io_limits_enabled; 60461007b31SStefan Hajnoczi bs->io_limits_enabled = false; 60561007b31SStefan Hajnoczi ret = bdrv_read(bs, sector_num, buf, nb_sectors); 60661007b31SStefan Hajnoczi bs->io_limits_enabled = enabled; 60761007b31SStefan Hajnoczi return ret; 60861007b31SStefan Hajnoczi } 60961007b31SStefan Hajnoczi 61061007b31SStefan Hajnoczi /* Return < 0 if error. Important errors are: 61161007b31SStefan Hajnoczi -EIO generic I/O error (may happen for all errors) 61261007b31SStefan Hajnoczi -ENOMEDIUM No media inserted. 61361007b31SStefan Hajnoczi -EINVAL Invalid sector number or nb_sectors 61461007b31SStefan Hajnoczi -EACCES Trying to write a read-only device 61561007b31SStefan Hajnoczi */ 61661007b31SStefan Hajnoczi int bdrv_write(BlockDriverState *bs, int64_t sector_num, 61761007b31SStefan Hajnoczi const uint8_t *buf, int nb_sectors) 61861007b31SStefan Hajnoczi { 61961007b31SStefan Hajnoczi return bdrv_rw_co(bs, sector_num, (uint8_t *)buf, nb_sectors, true, 0); 62061007b31SStefan Hajnoczi } 62161007b31SStefan Hajnoczi 62261007b31SStefan Hajnoczi int bdrv_write_zeroes(BlockDriverState *bs, int64_t sector_num, 62361007b31SStefan Hajnoczi int nb_sectors, BdrvRequestFlags flags) 62461007b31SStefan Hajnoczi { 62561007b31SStefan Hajnoczi return bdrv_rw_co(bs, sector_num, NULL, nb_sectors, true, 62661007b31SStefan Hajnoczi BDRV_REQ_ZERO_WRITE | flags); 62761007b31SStefan Hajnoczi } 62861007b31SStefan Hajnoczi 62961007b31SStefan Hajnoczi /* 63061007b31SStefan Hajnoczi * Completely zero out a block device with the help of bdrv_write_zeroes. 63161007b31SStefan Hajnoczi * The operation is sped up by checking the block status and only writing 63261007b31SStefan Hajnoczi * zeroes to the device if they currently do not return zeroes. Optional 63361007b31SStefan Hajnoczi * flags are passed through to bdrv_write_zeroes (e.g. BDRV_REQ_MAY_UNMAP). 63461007b31SStefan Hajnoczi * 63561007b31SStefan Hajnoczi * Returns < 0 on error, 0 on success. For error codes see bdrv_write(). 63661007b31SStefan Hajnoczi */ 63761007b31SStefan Hajnoczi int bdrv_make_zero(BlockDriverState *bs, BdrvRequestFlags flags) 63861007b31SStefan Hajnoczi { 63961007b31SStefan Hajnoczi int64_t target_sectors, ret, nb_sectors, sector_num = 0; 64061007b31SStefan Hajnoczi int n; 64161007b31SStefan Hajnoczi 64261007b31SStefan Hajnoczi target_sectors = bdrv_nb_sectors(bs); 64361007b31SStefan Hajnoczi if (target_sectors < 0) { 64461007b31SStefan Hajnoczi return target_sectors; 64561007b31SStefan Hajnoczi } 64661007b31SStefan Hajnoczi 64761007b31SStefan Hajnoczi for (;;) { 64861007b31SStefan Hajnoczi nb_sectors = MIN(target_sectors - sector_num, BDRV_REQUEST_MAX_SECTORS); 64961007b31SStefan Hajnoczi if (nb_sectors <= 0) { 65061007b31SStefan Hajnoczi return 0; 65161007b31SStefan Hajnoczi } 65261007b31SStefan Hajnoczi ret = bdrv_get_block_status(bs, sector_num, nb_sectors, &n); 65361007b31SStefan Hajnoczi if (ret < 0) { 65461007b31SStefan Hajnoczi error_report("error getting block status at sector %" PRId64 ": %s", 65561007b31SStefan Hajnoczi sector_num, strerror(-ret)); 65661007b31SStefan Hajnoczi return ret; 65761007b31SStefan Hajnoczi } 65861007b31SStefan Hajnoczi if (ret & BDRV_BLOCK_ZERO) { 65961007b31SStefan Hajnoczi sector_num += n; 66061007b31SStefan Hajnoczi continue; 66161007b31SStefan Hajnoczi } 66261007b31SStefan Hajnoczi ret = bdrv_write_zeroes(bs, sector_num, n, flags); 66361007b31SStefan Hajnoczi if (ret < 0) { 66461007b31SStefan Hajnoczi error_report("error writing zeroes at sector %" PRId64 ": %s", 66561007b31SStefan Hajnoczi sector_num, strerror(-ret)); 66661007b31SStefan Hajnoczi return ret; 66761007b31SStefan Hajnoczi } 66861007b31SStefan Hajnoczi sector_num += n; 66961007b31SStefan Hajnoczi } 67061007b31SStefan Hajnoczi } 67161007b31SStefan Hajnoczi 67261007b31SStefan Hajnoczi int bdrv_pread(BlockDriverState *bs, int64_t offset, void *buf, int bytes) 67361007b31SStefan Hajnoczi { 67461007b31SStefan Hajnoczi QEMUIOVector qiov; 67561007b31SStefan Hajnoczi struct iovec iov = { 67661007b31SStefan Hajnoczi .iov_base = (void *)buf, 67761007b31SStefan Hajnoczi .iov_len = bytes, 67861007b31SStefan Hajnoczi }; 67961007b31SStefan Hajnoczi int ret; 68061007b31SStefan Hajnoczi 68161007b31SStefan Hajnoczi if (bytes < 0) { 68261007b31SStefan Hajnoczi return -EINVAL; 68361007b31SStefan Hajnoczi } 68461007b31SStefan Hajnoczi 68561007b31SStefan Hajnoczi qemu_iovec_init_external(&qiov, &iov, 1); 68661007b31SStefan Hajnoczi ret = bdrv_prwv_co(bs, offset, &qiov, false, 0); 68761007b31SStefan Hajnoczi if (ret < 0) { 68861007b31SStefan Hajnoczi return ret; 68961007b31SStefan Hajnoczi } 69061007b31SStefan Hajnoczi 69161007b31SStefan Hajnoczi return bytes; 69261007b31SStefan Hajnoczi } 69361007b31SStefan Hajnoczi 69461007b31SStefan Hajnoczi int bdrv_pwritev(BlockDriverState *bs, int64_t offset, QEMUIOVector *qiov) 69561007b31SStefan Hajnoczi { 69661007b31SStefan Hajnoczi int ret; 69761007b31SStefan Hajnoczi 69861007b31SStefan Hajnoczi ret = bdrv_prwv_co(bs, offset, qiov, true, 0); 69961007b31SStefan Hajnoczi if (ret < 0) { 70061007b31SStefan Hajnoczi return ret; 70161007b31SStefan Hajnoczi } 70261007b31SStefan Hajnoczi 70361007b31SStefan Hajnoczi return qiov->size; 70461007b31SStefan Hajnoczi } 70561007b31SStefan Hajnoczi 70661007b31SStefan Hajnoczi int bdrv_pwrite(BlockDriverState *bs, int64_t offset, 70761007b31SStefan Hajnoczi const void *buf, int bytes) 70861007b31SStefan Hajnoczi { 70961007b31SStefan Hajnoczi QEMUIOVector qiov; 71061007b31SStefan Hajnoczi struct iovec iov = { 71161007b31SStefan Hajnoczi .iov_base = (void *) buf, 71261007b31SStefan Hajnoczi .iov_len = bytes, 71361007b31SStefan Hajnoczi }; 71461007b31SStefan Hajnoczi 71561007b31SStefan Hajnoczi if (bytes < 0) { 71661007b31SStefan Hajnoczi return -EINVAL; 71761007b31SStefan Hajnoczi } 71861007b31SStefan Hajnoczi 71961007b31SStefan Hajnoczi qemu_iovec_init_external(&qiov, &iov, 1); 72061007b31SStefan Hajnoczi return bdrv_pwritev(bs, offset, &qiov); 72161007b31SStefan Hajnoczi } 72261007b31SStefan Hajnoczi 72361007b31SStefan Hajnoczi /* 72461007b31SStefan Hajnoczi * Writes to the file and ensures that no writes are reordered across this 72561007b31SStefan Hajnoczi * request (acts as a barrier) 72661007b31SStefan Hajnoczi * 72761007b31SStefan Hajnoczi * Returns 0 on success, -errno in error cases. 72861007b31SStefan Hajnoczi */ 72961007b31SStefan Hajnoczi int bdrv_pwrite_sync(BlockDriverState *bs, int64_t offset, 73061007b31SStefan Hajnoczi const void *buf, int count) 73161007b31SStefan Hajnoczi { 73261007b31SStefan Hajnoczi int ret; 73361007b31SStefan Hajnoczi 73461007b31SStefan Hajnoczi ret = bdrv_pwrite(bs, offset, buf, count); 73561007b31SStefan Hajnoczi if (ret < 0) { 73661007b31SStefan Hajnoczi return ret; 73761007b31SStefan Hajnoczi } 73861007b31SStefan Hajnoczi 73961007b31SStefan Hajnoczi /* No flush needed for cache modes that already do it */ 74061007b31SStefan Hajnoczi if (bs->enable_write_cache) { 74161007b31SStefan Hajnoczi bdrv_flush(bs); 74261007b31SStefan Hajnoczi } 74361007b31SStefan Hajnoczi 74461007b31SStefan Hajnoczi return 0; 74561007b31SStefan Hajnoczi } 74661007b31SStefan Hajnoczi 74761007b31SStefan Hajnoczi static int coroutine_fn bdrv_co_do_copy_on_readv(BlockDriverState *bs, 74861007b31SStefan Hajnoczi int64_t sector_num, int nb_sectors, QEMUIOVector *qiov) 74961007b31SStefan Hajnoczi { 75061007b31SStefan Hajnoczi /* Perform I/O through a temporary buffer so that users who scribble over 75161007b31SStefan Hajnoczi * their read buffer while the operation is in progress do not end up 75261007b31SStefan Hajnoczi * modifying the image file. This is critical for zero-copy guest I/O 75361007b31SStefan Hajnoczi * where anything might happen inside guest memory. 75461007b31SStefan Hajnoczi */ 75561007b31SStefan Hajnoczi void *bounce_buffer; 75661007b31SStefan Hajnoczi 75761007b31SStefan Hajnoczi BlockDriver *drv = bs->drv; 75861007b31SStefan Hajnoczi struct iovec iov; 75961007b31SStefan Hajnoczi QEMUIOVector bounce_qiov; 76061007b31SStefan Hajnoczi int64_t cluster_sector_num; 76161007b31SStefan Hajnoczi int cluster_nb_sectors; 76261007b31SStefan Hajnoczi size_t skip_bytes; 76361007b31SStefan Hajnoczi int ret; 76461007b31SStefan Hajnoczi 76561007b31SStefan Hajnoczi /* Cover entire cluster so no additional backing file I/O is required when 76661007b31SStefan Hajnoczi * allocating cluster in the image file. 76761007b31SStefan Hajnoczi */ 76861007b31SStefan Hajnoczi bdrv_round_to_clusters(bs, sector_num, nb_sectors, 76961007b31SStefan Hajnoczi &cluster_sector_num, &cluster_nb_sectors); 77061007b31SStefan Hajnoczi 77161007b31SStefan Hajnoczi trace_bdrv_co_do_copy_on_readv(bs, sector_num, nb_sectors, 77261007b31SStefan Hajnoczi cluster_sector_num, cluster_nb_sectors); 77361007b31SStefan Hajnoczi 77461007b31SStefan Hajnoczi iov.iov_len = cluster_nb_sectors * BDRV_SECTOR_SIZE; 77561007b31SStefan Hajnoczi iov.iov_base = bounce_buffer = qemu_try_blockalign(bs, iov.iov_len); 77661007b31SStefan Hajnoczi if (bounce_buffer == NULL) { 77761007b31SStefan Hajnoczi ret = -ENOMEM; 77861007b31SStefan Hajnoczi goto err; 77961007b31SStefan Hajnoczi } 78061007b31SStefan Hajnoczi 78161007b31SStefan Hajnoczi qemu_iovec_init_external(&bounce_qiov, &iov, 1); 78261007b31SStefan Hajnoczi 78361007b31SStefan Hajnoczi ret = drv->bdrv_co_readv(bs, cluster_sector_num, cluster_nb_sectors, 78461007b31SStefan Hajnoczi &bounce_qiov); 78561007b31SStefan Hajnoczi if (ret < 0) { 78661007b31SStefan Hajnoczi goto err; 78761007b31SStefan Hajnoczi } 78861007b31SStefan Hajnoczi 78961007b31SStefan Hajnoczi if (drv->bdrv_co_write_zeroes && 79061007b31SStefan Hajnoczi buffer_is_zero(bounce_buffer, iov.iov_len)) { 79161007b31SStefan Hajnoczi ret = bdrv_co_do_write_zeroes(bs, cluster_sector_num, 79261007b31SStefan Hajnoczi cluster_nb_sectors, 0); 79361007b31SStefan Hajnoczi } else { 79461007b31SStefan Hajnoczi /* This does not change the data on the disk, it is not necessary 79561007b31SStefan Hajnoczi * to flush even in cache=writethrough mode. 79661007b31SStefan Hajnoczi */ 79761007b31SStefan Hajnoczi ret = drv->bdrv_co_writev(bs, cluster_sector_num, cluster_nb_sectors, 79861007b31SStefan Hajnoczi &bounce_qiov); 79961007b31SStefan Hajnoczi } 80061007b31SStefan Hajnoczi 80161007b31SStefan Hajnoczi if (ret < 0) { 80261007b31SStefan Hajnoczi /* It might be okay to ignore write errors for guest requests. If this 80361007b31SStefan Hajnoczi * is a deliberate copy-on-read then we don't want to ignore the error. 80461007b31SStefan Hajnoczi * Simply report it in all cases. 80561007b31SStefan Hajnoczi */ 80661007b31SStefan Hajnoczi goto err; 80761007b31SStefan Hajnoczi } 80861007b31SStefan Hajnoczi 80961007b31SStefan Hajnoczi skip_bytes = (sector_num - cluster_sector_num) * BDRV_SECTOR_SIZE; 81061007b31SStefan Hajnoczi qemu_iovec_from_buf(qiov, 0, bounce_buffer + skip_bytes, 81161007b31SStefan Hajnoczi nb_sectors * BDRV_SECTOR_SIZE); 81261007b31SStefan Hajnoczi 81361007b31SStefan Hajnoczi err: 81461007b31SStefan Hajnoczi qemu_vfree(bounce_buffer); 81561007b31SStefan Hajnoczi return ret; 81661007b31SStefan Hajnoczi } 81761007b31SStefan Hajnoczi 81861007b31SStefan Hajnoczi /* 81961007b31SStefan Hajnoczi * Forwards an already correctly aligned request to the BlockDriver. This 82061007b31SStefan Hajnoczi * handles copy on read and zeroing after EOF; any other features must be 82161007b31SStefan Hajnoczi * implemented by the caller. 82261007b31SStefan Hajnoczi */ 82361007b31SStefan Hajnoczi static int coroutine_fn bdrv_aligned_preadv(BlockDriverState *bs, 82461007b31SStefan Hajnoczi BdrvTrackedRequest *req, int64_t offset, unsigned int bytes, 82561007b31SStefan Hajnoczi int64_t align, QEMUIOVector *qiov, int flags) 82661007b31SStefan Hajnoczi { 82761007b31SStefan Hajnoczi BlockDriver *drv = bs->drv; 82861007b31SStefan Hajnoczi int ret; 82961007b31SStefan Hajnoczi 83061007b31SStefan Hajnoczi int64_t sector_num = offset >> BDRV_SECTOR_BITS; 83161007b31SStefan Hajnoczi unsigned int nb_sectors = bytes >> BDRV_SECTOR_BITS; 83261007b31SStefan Hajnoczi 83361007b31SStefan Hajnoczi assert((offset & (BDRV_SECTOR_SIZE - 1)) == 0); 83461007b31SStefan Hajnoczi assert((bytes & (BDRV_SECTOR_SIZE - 1)) == 0); 83561007b31SStefan Hajnoczi assert(!qiov || bytes == qiov->size); 83661007b31SStefan Hajnoczi 83761007b31SStefan Hajnoczi /* Handle Copy on Read and associated serialisation */ 83861007b31SStefan Hajnoczi if (flags & BDRV_REQ_COPY_ON_READ) { 83961007b31SStefan Hajnoczi /* If we touch the same cluster it counts as an overlap. This 84061007b31SStefan Hajnoczi * guarantees that allocating writes will be serialized and not race 84161007b31SStefan Hajnoczi * with each other for the same cluster. For example, in copy-on-read 84261007b31SStefan Hajnoczi * it ensures that the CoR read and write operations are atomic and 84361007b31SStefan Hajnoczi * guest writes cannot interleave between them. */ 84461007b31SStefan Hajnoczi mark_request_serialising(req, bdrv_get_cluster_size(bs)); 84561007b31SStefan Hajnoczi } 84661007b31SStefan Hajnoczi 84761007b31SStefan Hajnoczi wait_serialising_requests(req); 84861007b31SStefan Hajnoczi 84961007b31SStefan Hajnoczi if (flags & BDRV_REQ_COPY_ON_READ) { 85061007b31SStefan Hajnoczi int pnum; 85161007b31SStefan Hajnoczi 85261007b31SStefan Hajnoczi ret = bdrv_is_allocated(bs, sector_num, nb_sectors, &pnum); 85361007b31SStefan Hajnoczi if (ret < 0) { 85461007b31SStefan Hajnoczi goto out; 85561007b31SStefan Hajnoczi } 85661007b31SStefan Hajnoczi 85761007b31SStefan Hajnoczi if (!ret || pnum != nb_sectors) { 85861007b31SStefan Hajnoczi ret = bdrv_co_do_copy_on_readv(bs, sector_num, nb_sectors, qiov); 85961007b31SStefan Hajnoczi goto out; 86061007b31SStefan Hajnoczi } 86161007b31SStefan Hajnoczi } 86261007b31SStefan Hajnoczi 86361007b31SStefan Hajnoczi /* Forward the request to the BlockDriver */ 86461007b31SStefan Hajnoczi if (!bs->zero_beyond_eof) { 86561007b31SStefan Hajnoczi ret = drv->bdrv_co_readv(bs, sector_num, nb_sectors, qiov); 86661007b31SStefan Hajnoczi } else { 86761007b31SStefan Hajnoczi /* Read zeros after EOF */ 86861007b31SStefan Hajnoczi int64_t total_sectors, max_nb_sectors; 86961007b31SStefan Hajnoczi 87061007b31SStefan Hajnoczi total_sectors = bdrv_nb_sectors(bs); 87161007b31SStefan Hajnoczi if (total_sectors < 0) { 87261007b31SStefan Hajnoczi ret = total_sectors; 87361007b31SStefan Hajnoczi goto out; 87461007b31SStefan Hajnoczi } 87561007b31SStefan Hajnoczi 87661007b31SStefan Hajnoczi max_nb_sectors = ROUND_UP(MAX(0, total_sectors - sector_num), 87761007b31SStefan Hajnoczi align >> BDRV_SECTOR_BITS); 87861007b31SStefan Hajnoczi if (nb_sectors < max_nb_sectors) { 87961007b31SStefan Hajnoczi ret = drv->bdrv_co_readv(bs, sector_num, nb_sectors, qiov); 88061007b31SStefan Hajnoczi } else if (max_nb_sectors > 0) { 88161007b31SStefan Hajnoczi QEMUIOVector local_qiov; 88261007b31SStefan Hajnoczi 88361007b31SStefan Hajnoczi qemu_iovec_init(&local_qiov, qiov->niov); 88461007b31SStefan Hajnoczi qemu_iovec_concat(&local_qiov, qiov, 0, 88561007b31SStefan Hajnoczi max_nb_sectors * BDRV_SECTOR_SIZE); 88661007b31SStefan Hajnoczi 88761007b31SStefan Hajnoczi ret = drv->bdrv_co_readv(bs, sector_num, max_nb_sectors, 88861007b31SStefan Hajnoczi &local_qiov); 88961007b31SStefan Hajnoczi 89061007b31SStefan Hajnoczi qemu_iovec_destroy(&local_qiov); 89161007b31SStefan Hajnoczi } else { 89261007b31SStefan Hajnoczi ret = 0; 89361007b31SStefan Hajnoczi } 89461007b31SStefan Hajnoczi 89561007b31SStefan Hajnoczi /* Reading beyond end of file is supposed to produce zeroes */ 89661007b31SStefan Hajnoczi if (ret == 0 && total_sectors < sector_num + nb_sectors) { 89761007b31SStefan Hajnoczi uint64_t offset = MAX(0, total_sectors - sector_num); 89861007b31SStefan Hajnoczi uint64_t bytes = (sector_num + nb_sectors - offset) * 89961007b31SStefan Hajnoczi BDRV_SECTOR_SIZE; 90061007b31SStefan Hajnoczi qemu_iovec_memset(qiov, offset * BDRV_SECTOR_SIZE, 0, bytes); 90161007b31SStefan Hajnoczi } 90261007b31SStefan Hajnoczi } 90361007b31SStefan Hajnoczi 90461007b31SStefan Hajnoczi out: 90561007b31SStefan Hajnoczi return ret; 90661007b31SStefan Hajnoczi } 90761007b31SStefan Hajnoczi 90861007b31SStefan Hajnoczi /* 90961007b31SStefan Hajnoczi * Handle a read request in coroutine context 91061007b31SStefan Hajnoczi */ 91161007b31SStefan Hajnoczi static int coroutine_fn bdrv_co_do_preadv(BlockDriverState *bs, 91261007b31SStefan Hajnoczi int64_t offset, unsigned int bytes, QEMUIOVector *qiov, 91361007b31SStefan Hajnoczi BdrvRequestFlags flags) 91461007b31SStefan Hajnoczi { 91561007b31SStefan Hajnoczi BlockDriver *drv = bs->drv; 91661007b31SStefan Hajnoczi BdrvTrackedRequest req; 91761007b31SStefan Hajnoczi 918d01c07f2SFam Zheng /* TODO Lift BDRV_SECTOR_SIZE restriction in BlockDriver interface */ 919d01c07f2SFam Zheng uint64_t align = MAX(BDRV_SECTOR_SIZE, bs->request_alignment); 92061007b31SStefan Hajnoczi uint8_t *head_buf = NULL; 92161007b31SStefan Hajnoczi uint8_t *tail_buf = NULL; 92261007b31SStefan Hajnoczi QEMUIOVector local_qiov; 92361007b31SStefan Hajnoczi bool use_local_qiov = false; 92461007b31SStefan Hajnoczi int ret; 92561007b31SStefan Hajnoczi 92661007b31SStefan Hajnoczi if (!drv) { 92761007b31SStefan Hajnoczi return -ENOMEDIUM; 92861007b31SStefan Hajnoczi } 92961007b31SStefan Hajnoczi 93061007b31SStefan Hajnoczi ret = bdrv_check_byte_request(bs, offset, bytes); 93161007b31SStefan Hajnoczi if (ret < 0) { 93261007b31SStefan Hajnoczi return ret; 93361007b31SStefan Hajnoczi } 93461007b31SStefan Hajnoczi 9359568b511SWen Congyang /* Don't do copy-on-read if we read data before write operation */ 9369568b511SWen Congyang if (bs->copy_on_read && !(flags & BDRV_REQ_NO_COPY_ON_READ)) { 93761007b31SStefan Hajnoczi flags |= BDRV_REQ_COPY_ON_READ; 93861007b31SStefan Hajnoczi } 93961007b31SStefan Hajnoczi 94061007b31SStefan Hajnoczi /* throttling disk I/O */ 94161007b31SStefan Hajnoczi if (bs->io_limits_enabled) { 94276f4afb4SAlberto Garcia throttle_group_co_io_limits_intercept(bs, bytes, false); 94361007b31SStefan Hajnoczi } 94461007b31SStefan Hajnoczi 94561007b31SStefan Hajnoczi /* Align read if necessary by padding qiov */ 94661007b31SStefan Hajnoczi if (offset & (align - 1)) { 94761007b31SStefan Hajnoczi head_buf = qemu_blockalign(bs, align); 94861007b31SStefan Hajnoczi qemu_iovec_init(&local_qiov, qiov->niov + 2); 94961007b31SStefan Hajnoczi qemu_iovec_add(&local_qiov, head_buf, offset & (align - 1)); 95061007b31SStefan Hajnoczi qemu_iovec_concat(&local_qiov, qiov, 0, qiov->size); 95161007b31SStefan Hajnoczi use_local_qiov = true; 95261007b31SStefan Hajnoczi 95361007b31SStefan Hajnoczi bytes += offset & (align - 1); 95461007b31SStefan Hajnoczi offset = offset & ~(align - 1); 95561007b31SStefan Hajnoczi } 95661007b31SStefan Hajnoczi 95761007b31SStefan Hajnoczi if ((offset + bytes) & (align - 1)) { 95861007b31SStefan Hajnoczi if (!use_local_qiov) { 95961007b31SStefan Hajnoczi qemu_iovec_init(&local_qiov, qiov->niov + 1); 96061007b31SStefan Hajnoczi qemu_iovec_concat(&local_qiov, qiov, 0, qiov->size); 96161007b31SStefan Hajnoczi use_local_qiov = true; 96261007b31SStefan Hajnoczi } 96361007b31SStefan Hajnoczi tail_buf = qemu_blockalign(bs, align); 96461007b31SStefan Hajnoczi qemu_iovec_add(&local_qiov, tail_buf, 96561007b31SStefan Hajnoczi align - ((offset + bytes) & (align - 1))); 96661007b31SStefan Hajnoczi 96761007b31SStefan Hajnoczi bytes = ROUND_UP(bytes, align); 96861007b31SStefan Hajnoczi } 96961007b31SStefan Hajnoczi 97061007b31SStefan Hajnoczi tracked_request_begin(&req, bs, offset, bytes, false); 97161007b31SStefan Hajnoczi ret = bdrv_aligned_preadv(bs, &req, offset, bytes, align, 97261007b31SStefan Hajnoczi use_local_qiov ? &local_qiov : qiov, 97361007b31SStefan Hajnoczi flags); 97461007b31SStefan Hajnoczi tracked_request_end(&req); 97561007b31SStefan Hajnoczi 97661007b31SStefan Hajnoczi if (use_local_qiov) { 97761007b31SStefan Hajnoczi qemu_iovec_destroy(&local_qiov); 97861007b31SStefan Hajnoczi qemu_vfree(head_buf); 97961007b31SStefan Hajnoczi qemu_vfree(tail_buf); 98061007b31SStefan Hajnoczi } 98161007b31SStefan Hajnoczi 98261007b31SStefan Hajnoczi return ret; 98361007b31SStefan Hajnoczi } 98461007b31SStefan Hajnoczi 98561007b31SStefan Hajnoczi static int coroutine_fn bdrv_co_do_readv(BlockDriverState *bs, 98661007b31SStefan Hajnoczi int64_t sector_num, int nb_sectors, QEMUIOVector *qiov, 98761007b31SStefan Hajnoczi BdrvRequestFlags flags) 98861007b31SStefan Hajnoczi { 98961007b31SStefan Hajnoczi if (nb_sectors < 0 || nb_sectors > BDRV_REQUEST_MAX_SECTORS) { 99061007b31SStefan Hajnoczi return -EINVAL; 99161007b31SStefan Hajnoczi } 99261007b31SStefan Hajnoczi 99361007b31SStefan Hajnoczi return bdrv_co_do_preadv(bs, sector_num << BDRV_SECTOR_BITS, 99461007b31SStefan Hajnoczi nb_sectors << BDRV_SECTOR_BITS, qiov, flags); 99561007b31SStefan Hajnoczi } 99661007b31SStefan Hajnoczi 99761007b31SStefan Hajnoczi int coroutine_fn bdrv_co_readv(BlockDriverState *bs, int64_t sector_num, 99861007b31SStefan Hajnoczi int nb_sectors, QEMUIOVector *qiov) 99961007b31SStefan Hajnoczi { 100061007b31SStefan Hajnoczi trace_bdrv_co_readv(bs, sector_num, nb_sectors); 100161007b31SStefan Hajnoczi 100261007b31SStefan Hajnoczi return bdrv_co_do_readv(bs, sector_num, nb_sectors, qiov, 0); 100361007b31SStefan Hajnoczi } 100461007b31SStefan Hajnoczi 10059568b511SWen Congyang int coroutine_fn bdrv_co_no_copy_on_readv(BlockDriverState *bs, 10069568b511SWen Congyang int64_t sector_num, int nb_sectors, QEMUIOVector *qiov) 10079568b511SWen Congyang { 10089568b511SWen Congyang trace_bdrv_co_no_copy_on_readv(bs, sector_num, nb_sectors); 10099568b511SWen Congyang 10109568b511SWen Congyang return bdrv_co_do_readv(bs, sector_num, nb_sectors, qiov, 10119568b511SWen Congyang BDRV_REQ_NO_COPY_ON_READ); 10129568b511SWen Congyang } 10139568b511SWen Congyang 101461007b31SStefan Hajnoczi int coroutine_fn bdrv_co_copy_on_readv(BlockDriverState *bs, 101561007b31SStefan Hajnoczi int64_t sector_num, int nb_sectors, QEMUIOVector *qiov) 101661007b31SStefan Hajnoczi { 101761007b31SStefan Hajnoczi trace_bdrv_co_copy_on_readv(bs, sector_num, nb_sectors); 101861007b31SStefan Hajnoczi 101961007b31SStefan Hajnoczi return bdrv_co_do_readv(bs, sector_num, nb_sectors, qiov, 102061007b31SStefan Hajnoczi BDRV_REQ_COPY_ON_READ); 102161007b31SStefan Hajnoczi } 102261007b31SStefan Hajnoczi 102361007b31SStefan Hajnoczi #define MAX_WRITE_ZEROES_BOUNCE_BUFFER 32768 102461007b31SStefan Hajnoczi 102561007b31SStefan Hajnoczi static int coroutine_fn bdrv_co_do_write_zeroes(BlockDriverState *bs, 102661007b31SStefan Hajnoczi int64_t sector_num, int nb_sectors, BdrvRequestFlags flags) 102761007b31SStefan Hajnoczi { 102861007b31SStefan Hajnoczi BlockDriver *drv = bs->drv; 102961007b31SStefan Hajnoczi QEMUIOVector qiov; 103061007b31SStefan Hajnoczi struct iovec iov = {0}; 103161007b31SStefan Hajnoczi int ret = 0; 103261007b31SStefan Hajnoczi 103361007b31SStefan Hajnoczi int max_write_zeroes = MIN_NON_ZERO(bs->bl.max_write_zeroes, 103461007b31SStefan Hajnoczi BDRV_REQUEST_MAX_SECTORS); 103561007b31SStefan Hajnoczi 103661007b31SStefan Hajnoczi while (nb_sectors > 0 && !ret) { 103761007b31SStefan Hajnoczi int num = nb_sectors; 103861007b31SStefan Hajnoczi 103961007b31SStefan Hajnoczi /* Align request. Block drivers can expect the "bulk" of the request 104061007b31SStefan Hajnoczi * to be aligned. 104161007b31SStefan Hajnoczi */ 104261007b31SStefan Hajnoczi if (bs->bl.write_zeroes_alignment 104361007b31SStefan Hajnoczi && num > bs->bl.write_zeroes_alignment) { 104461007b31SStefan Hajnoczi if (sector_num % bs->bl.write_zeroes_alignment != 0) { 104561007b31SStefan Hajnoczi /* Make a small request up to the first aligned sector. */ 104661007b31SStefan Hajnoczi num = bs->bl.write_zeroes_alignment; 104761007b31SStefan Hajnoczi num -= sector_num % bs->bl.write_zeroes_alignment; 104861007b31SStefan Hajnoczi } else if ((sector_num + num) % bs->bl.write_zeroes_alignment != 0) { 104961007b31SStefan Hajnoczi /* Shorten the request to the last aligned sector. num cannot 105061007b31SStefan Hajnoczi * underflow because num > bs->bl.write_zeroes_alignment. 105161007b31SStefan Hajnoczi */ 105261007b31SStefan Hajnoczi num -= (sector_num + num) % bs->bl.write_zeroes_alignment; 105361007b31SStefan Hajnoczi } 105461007b31SStefan Hajnoczi } 105561007b31SStefan Hajnoczi 105661007b31SStefan Hajnoczi /* limit request size */ 105761007b31SStefan Hajnoczi if (num > max_write_zeroes) { 105861007b31SStefan Hajnoczi num = max_write_zeroes; 105961007b31SStefan Hajnoczi } 106061007b31SStefan Hajnoczi 106161007b31SStefan Hajnoczi ret = -ENOTSUP; 106261007b31SStefan Hajnoczi /* First try the efficient write zeroes operation */ 106361007b31SStefan Hajnoczi if (drv->bdrv_co_write_zeroes) { 106461007b31SStefan Hajnoczi ret = drv->bdrv_co_write_zeroes(bs, sector_num, num, flags); 106561007b31SStefan Hajnoczi } 106661007b31SStefan Hajnoczi 106761007b31SStefan Hajnoczi if (ret == -ENOTSUP) { 106861007b31SStefan Hajnoczi /* Fall back to bounce buffer if write zeroes is unsupported */ 106961007b31SStefan Hajnoczi int max_xfer_len = MIN_NON_ZERO(bs->bl.max_transfer_length, 107061007b31SStefan Hajnoczi MAX_WRITE_ZEROES_BOUNCE_BUFFER); 107161007b31SStefan Hajnoczi num = MIN(num, max_xfer_len); 107261007b31SStefan Hajnoczi iov.iov_len = num * BDRV_SECTOR_SIZE; 107361007b31SStefan Hajnoczi if (iov.iov_base == NULL) { 107461007b31SStefan Hajnoczi iov.iov_base = qemu_try_blockalign(bs, num * BDRV_SECTOR_SIZE); 107561007b31SStefan Hajnoczi if (iov.iov_base == NULL) { 107661007b31SStefan Hajnoczi ret = -ENOMEM; 107761007b31SStefan Hajnoczi goto fail; 107861007b31SStefan Hajnoczi } 107961007b31SStefan Hajnoczi memset(iov.iov_base, 0, num * BDRV_SECTOR_SIZE); 108061007b31SStefan Hajnoczi } 108161007b31SStefan Hajnoczi qemu_iovec_init_external(&qiov, &iov, 1); 108261007b31SStefan Hajnoczi 108361007b31SStefan Hajnoczi ret = drv->bdrv_co_writev(bs, sector_num, num, &qiov); 108461007b31SStefan Hajnoczi 108561007b31SStefan Hajnoczi /* Keep bounce buffer around if it is big enough for all 108661007b31SStefan Hajnoczi * all future requests. 108761007b31SStefan Hajnoczi */ 108861007b31SStefan Hajnoczi if (num < max_xfer_len) { 108961007b31SStefan Hajnoczi qemu_vfree(iov.iov_base); 109061007b31SStefan Hajnoczi iov.iov_base = NULL; 109161007b31SStefan Hajnoczi } 109261007b31SStefan Hajnoczi } 109361007b31SStefan Hajnoczi 109461007b31SStefan Hajnoczi sector_num += num; 109561007b31SStefan Hajnoczi nb_sectors -= num; 109661007b31SStefan Hajnoczi } 109761007b31SStefan Hajnoczi 109861007b31SStefan Hajnoczi fail: 109961007b31SStefan Hajnoczi qemu_vfree(iov.iov_base); 110061007b31SStefan Hajnoczi return ret; 110161007b31SStefan Hajnoczi } 110261007b31SStefan Hajnoczi 110361007b31SStefan Hajnoczi /* 110461007b31SStefan Hajnoczi * Forwards an already correctly aligned write request to the BlockDriver. 110561007b31SStefan Hajnoczi */ 110661007b31SStefan Hajnoczi static int coroutine_fn bdrv_aligned_pwritev(BlockDriverState *bs, 110761007b31SStefan Hajnoczi BdrvTrackedRequest *req, int64_t offset, unsigned int bytes, 110861007b31SStefan Hajnoczi QEMUIOVector *qiov, int flags) 110961007b31SStefan Hajnoczi { 111061007b31SStefan Hajnoczi BlockDriver *drv = bs->drv; 111161007b31SStefan Hajnoczi bool waited; 111261007b31SStefan Hajnoczi int ret; 111361007b31SStefan Hajnoczi 111461007b31SStefan Hajnoczi int64_t sector_num = offset >> BDRV_SECTOR_BITS; 111561007b31SStefan Hajnoczi unsigned int nb_sectors = bytes >> BDRV_SECTOR_BITS; 111661007b31SStefan Hajnoczi 111761007b31SStefan Hajnoczi assert((offset & (BDRV_SECTOR_SIZE - 1)) == 0); 111861007b31SStefan Hajnoczi assert((bytes & (BDRV_SECTOR_SIZE - 1)) == 0); 111961007b31SStefan Hajnoczi assert(!qiov || bytes == qiov->size); 112061007b31SStefan Hajnoczi 112161007b31SStefan Hajnoczi waited = wait_serialising_requests(req); 112261007b31SStefan Hajnoczi assert(!waited || !req->serialising); 112361007b31SStefan Hajnoczi assert(req->overlap_offset <= offset); 112461007b31SStefan Hajnoczi assert(offset + bytes <= req->overlap_offset + req->overlap_bytes); 112561007b31SStefan Hajnoczi 112661007b31SStefan Hajnoczi ret = notifier_with_return_list_notify(&bs->before_write_notifiers, req); 112761007b31SStefan Hajnoczi 112861007b31SStefan Hajnoczi if (!ret && bs->detect_zeroes != BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF && 112961007b31SStefan Hajnoczi !(flags & BDRV_REQ_ZERO_WRITE) && drv->bdrv_co_write_zeroes && 113061007b31SStefan Hajnoczi qemu_iovec_is_zero(qiov)) { 113161007b31SStefan Hajnoczi flags |= BDRV_REQ_ZERO_WRITE; 113261007b31SStefan Hajnoczi if (bs->detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP) { 113361007b31SStefan Hajnoczi flags |= BDRV_REQ_MAY_UNMAP; 113461007b31SStefan Hajnoczi } 113561007b31SStefan Hajnoczi } 113661007b31SStefan Hajnoczi 113761007b31SStefan Hajnoczi if (ret < 0) { 113861007b31SStefan Hajnoczi /* Do nothing, write notifier decided to fail this request */ 113961007b31SStefan Hajnoczi } else if (flags & BDRV_REQ_ZERO_WRITE) { 11409a4f4c31SKevin Wolf bdrv_debug_event(bs, BLKDBG_PWRITEV_ZERO); 114161007b31SStefan Hajnoczi ret = bdrv_co_do_write_zeroes(bs, sector_num, nb_sectors, flags); 114261007b31SStefan Hajnoczi } else { 11439a4f4c31SKevin Wolf bdrv_debug_event(bs, BLKDBG_PWRITEV); 114461007b31SStefan Hajnoczi ret = drv->bdrv_co_writev(bs, sector_num, nb_sectors, qiov); 114561007b31SStefan Hajnoczi } 11469a4f4c31SKevin Wolf bdrv_debug_event(bs, BLKDBG_PWRITEV_DONE); 114761007b31SStefan Hajnoczi 114861007b31SStefan Hajnoczi if (ret == 0 && !bs->enable_write_cache) { 114961007b31SStefan Hajnoczi ret = bdrv_co_flush(bs); 115061007b31SStefan Hajnoczi } 115161007b31SStefan Hajnoczi 115261007b31SStefan Hajnoczi bdrv_set_dirty(bs, sector_num, nb_sectors); 115361007b31SStefan Hajnoczi 1154*53d8f9d8SMax Reitz if (bs->wr_highest_offset < offset + bytes) { 1155*53d8f9d8SMax Reitz bs->wr_highest_offset = offset + bytes; 1156*53d8f9d8SMax Reitz } 115761007b31SStefan Hajnoczi 115861007b31SStefan Hajnoczi if (ret >= 0) { 115961007b31SStefan Hajnoczi bs->total_sectors = MAX(bs->total_sectors, sector_num + nb_sectors); 116061007b31SStefan Hajnoczi } 116161007b31SStefan Hajnoczi 116261007b31SStefan Hajnoczi return ret; 116361007b31SStefan Hajnoczi } 116461007b31SStefan Hajnoczi 11659eeb6dd1SFam Zheng static int coroutine_fn bdrv_co_do_zero_pwritev(BlockDriverState *bs, 11669eeb6dd1SFam Zheng int64_t offset, 11679eeb6dd1SFam Zheng unsigned int bytes, 11689eeb6dd1SFam Zheng BdrvRequestFlags flags, 11699eeb6dd1SFam Zheng BdrvTrackedRequest *req) 11709eeb6dd1SFam Zheng { 11719eeb6dd1SFam Zheng uint8_t *buf = NULL; 11729eeb6dd1SFam Zheng QEMUIOVector local_qiov; 11739eeb6dd1SFam Zheng struct iovec iov; 11749eeb6dd1SFam Zheng uint64_t align = MAX(BDRV_SECTOR_SIZE, bs->request_alignment); 11759eeb6dd1SFam Zheng unsigned int head_padding_bytes, tail_padding_bytes; 11769eeb6dd1SFam Zheng int ret = 0; 11779eeb6dd1SFam Zheng 11789eeb6dd1SFam Zheng head_padding_bytes = offset & (align - 1); 11799eeb6dd1SFam Zheng tail_padding_bytes = align - ((offset + bytes) & (align - 1)); 11809eeb6dd1SFam Zheng 11819eeb6dd1SFam Zheng 11829eeb6dd1SFam Zheng assert(flags & BDRV_REQ_ZERO_WRITE); 11839eeb6dd1SFam Zheng if (head_padding_bytes || tail_padding_bytes) { 11849eeb6dd1SFam Zheng buf = qemu_blockalign(bs, align); 11859eeb6dd1SFam Zheng iov = (struct iovec) { 11869eeb6dd1SFam Zheng .iov_base = buf, 11879eeb6dd1SFam Zheng .iov_len = align, 11889eeb6dd1SFam Zheng }; 11899eeb6dd1SFam Zheng qemu_iovec_init_external(&local_qiov, &iov, 1); 11909eeb6dd1SFam Zheng } 11919eeb6dd1SFam Zheng if (head_padding_bytes) { 11929eeb6dd1SFam Zheng uint64_t zero_bytes = MIN(bytes, align - head_padding_bytes); 11939eeb6dd1SFam Zheng 11949eeb6dd1SFam Zheng /* RMW the unaligned part before head. */ 11959eeb6dd1SFam Zheng mark_request_serialising(req, align); 11969eeb6dd1SFam Zheng wait_serialising_requests(req); 11979a4f4c31SKevin Wolf bdrv_debug_event(bs, BLKDBG_PWRITEV_RMW_HEAD); 11989eeb6dd1SFam Zheng ret = bdrv_aligned_preadv(bs, req, offset & ~(align - 1), align, 11999eeb6dd1SFam Zheng align, &local_qiov, 0); 12009eeb6dd1SFam Zheng if (ret < 0) { 12019eeb6dd1SFam Zheng goto fail; 12029eeb6dd1SFam Zheng } 12039a4f4c31SKevin Wolf bdrv_debug_event(bs, BLKDBG_PWRITEV_RMW_AFTER_HEAD); 12049eeb6dd1SFam Zheng 12059eeb6dd1SFam Zheng memset(buf + head_padding_bytes, 0, zero_bytes); 12069eeb6dd1SFam Zheng ret = bdrv_aligned_pwritev(bs, req, offset & ~(align - 1), align, 12079eeb6dd1SFam Zheng &local_qiov, 12089eeb6dd1SFam Zheng flags & ~BDRV_REQ_ZERO_WRITE); 12099eeb6dd1SFam Zheng if (ret < 0) { 12109eeb6dd1SFam Zheng goto fail; 12119eeb6dd1SFam Zheng } 12129eeb6dd1SFam Zheng offset += zero_bytes; 12139eeb6dd1SFam Zheng bytes -= zero_bytes; 12149eeb6dd1SFam Zheng } 12159eeb6dd1SFam Zheng 12169eeb6dd1SFam Zheng assert(!bytes || (offset & (align - 1)) == 0); 12179eeb6dd1SFam Zheng if (bytes >= align) { 12189eeb6dd1SFam Zheng /* Write the aligned part in the middle. */ 12199eeb6dd1SFam Zheng uint64_t aligned_bytes = bytes & ~(align - 1); 12209eeb6dd1SFam Zheng ret = bdrv_aligned_pwritev(bs, req, offset, aligned_bytes, 12219eeb6dd1SFam Zheng NULL, flags); 12229eeb6dd1SFam Zheng if (ret < 0) { 12239eeb6dd1SFam Zheng goto fail; 12249eeb6dd1SFam Zheng } 12259eeb6dd1SFam Zheng bytes -= aligned_bytes; 12269eeb6dd1SFam Zheng offset += aligned_bytes; 12279eeb6dd1SFam Zheng } 12289eeb6dd1SFam Zheng 12299eeb6dd1SFam Zheng assert(!bytes || (offset & (align - 1)) == 0); 12309eeb6dd1SFam Zheng if (bytes) { 12319eeb6dd1SFam Zheng assert(align == tail_padding_bytes + bytes); 12329eeb6dd1SFam Zheng /* RMW the unaligned part after tail. */ 12339eeb6dd1SFam Zheng mark_request_serialising(req, align); 12349eeb6dd1SFam Zheng wait_serialising_requests(req); 12359a4f4c31SKevin Wolf bdrv_debug_event(bs, BLKDBG_PWRITEV_RMW_TAIL); 12369eeb6dd1SFam Zheng ret = bdrv_aligned_preadv(bs, req, offset, align, 12379eeb6dd1SFam Zheng align, &local_qiov, 0); 12389eeb6dd1SFam Zheng if (ret < 0) { 12399eeb6dd1SFam Zheng goto fail; 12409eeb6dd1SFam Zheng } 12419a4f4c31SKevin Wolf bdrv_debug_event(bs, BLKDBG_PWRITEV_RMW_AFTER_TAIL); 12429eeb6dd1SFam Zheng 12439eeb6dd1SFam Zheng memset(buf, 0, bytes); 12449eeb6dd1SFam Zheng ret = bdrv_aligned_pwritev(bs, req, offset, align, 12459eeb6dd1SFam Zheng &local_qiov, flags & ~BDRV_REQ_ZERO_WRITE); 12469eeb6dd1SFam Zheng } 12479eeb6dd1SFam Zheng fail: 12489eeb6dd1SFam Zheng qemu_vfree(buf); 12499eeb6dd1SFam Zheng return ret; 12509eeb6dd1SFam Zheng 12519eeb6dd1SFam Zheng } 12529eeb6dd1SFam Zheng 125361007b31SStefan Hajnoczi /* 125461007b31SStefan Hajnoczi * Handle a write request in coroutine context 125561007b31SStefan Hajnoczi */ 125661007b31SStefan Hajnoczi static int coroutine_fn bdrv_co_do_pwritev(BlockDriverState *bs, 125761007b31SStefan Hajnoczi int64_t offset, unsigned int bytes, QEMUIOVector *qiov, 125861007b31SStefan Hajnoczi BdrvRequestFlags flags) 125961007b31SStefan Hajnoczi { 126061007b31SStefan Hajnoczi BdrvTrackedRequest req; 1261d01c07f2SFam Zheng /* TODO Lift BDRV_SECTOR_SIZE restriction in BlockDriver interface */ 1262d01c07f2SFam Zheng uint64_t align = MAX(BDRV_SECTOR_SIZE, bs->request_alignment); 126361007b31SStefan Hajnoczi uint8_t *head_buf = NULL; 126461007b31SStefan Hajnoczi uint8_t *tail_buf = NULL; 126561007b31SStefan Hajnoczi QEMUIOVector local_qiov; 126661007b31SStefan Hajnoczi bool use_local_qiov = false; 126761007b31SStefan Hajnoczi int ret; 126861007b31SStefan Hajnoczi 126961007b31SStefan Hajnoczi if (!bs->drv) { 127061007b31SStefan Hajnoczi return -ENOMEDIUM; 127161007b31SStefan Hajnoczi } 127261007b31SStefan Hajnoczi if (bs->read_only) { 1273eaf5fe2dSPaolo Bonzini return -EPERM; 127461007b31SStefan Hajnoczi } 127561007b31SStefan Hajnoczi 127661007b31SStefan Hajnoczi ret = bdrv_check_byte_request(bs, offset, bytes); 127761007b31SStefan Hajnoczi if (ret < 0) { 127861007b31SStefan Hajnoczi return ret; 127961007b31SStefan Hajnoczi } 128061007b31SStefan Hajnoczi 128161007b31SStefan Hajnoczi /* throttling disk I/O */ 128261007b31SStefan Hajnoczi if (bs->io_limits_enabled) { 128376f4afb4SAlberto Garcia throttle_group_co_io_limits_intercept(bs, bytes, true); 128461007b31SStefan Hajnoczi } 128561007b31SStefan Hajnoczi 128661007b31SStefan Hajnoczi /* 128761007b31SStefan Hajnoczi * Align write if necessary by performing a read-modify-write cycle. 128861007b31SStefan Hajnoczi * Pad qiov with the read parts and be sure to have a tracked request not 128961007b31SStefan Hajnoczi * only for bdrv_aligned_pwritev, but also for the reads of the RMW cycle. 129061007b31SStefan Hajnoczi */ 129161007b31SStefan Hajnoczi tracked_request_begin(&req, bs, offset, bytes, true); 129261007b31SStefan Hajnoczi 12939eeb6dd1SFam Zheng if (!qiov) { 12949eeb6dd1SFam Zheng ret = bdrv_co_do_zero_pwritev(bs, offset, bytes, flags, &req); 12959eeb6dd1SFam Zheng goto out; 12969eeb6dd1SFam Zheng } 12979eeb6dd1SFam Zheng 129861007b31SStefan Hajnoczi if (offset & (align - 1)) { 129961007b31SStefan Hajnoczi QEMUIOVector head_qiov; 130061007b31SStefan Hajnoczi struct iovec head_iov; 130161007b31SStefan Hajnoczi 130261007b31SStefan Hajnoczi mark_request_serialising(&req, align); 130361007b31SStefan Hajnoczi wait_serialising_requests(&req); 130461007b31SStefan Hajnoczi 130561007b31SStefan Hajnoczi head_buf = qemu_blockalign(bs, align); 130661007b31SStefan Hajnoczi head_iov = (struct iovec) { 130761007b31SStefan Hajnoczi .iov_base = head_buf, 130861007b31SStefan Hajnoczi .iov_len = align, 130961007b31SStefan Hajnoczi }; 131061007b31SStefan Hajnoczi qemu_iovec_init_external(&head_qiov, &head_iov, 1); 131161007b31SStefan Hajnoczi 13129a4f4c31SKevin Wolf bdrv_debug_event(bs, BLKDBG_PWRITEV_RMW_HEAD); 131361007b31SStefan Hajnoczi ret = bdrv_aligned_preadv(bs, &req, offset & ~(align - 1), align, 131461007b31SStefan Hajnoczi align, &head_qiov, 0); 131561007b31SStefan Hajnoczi if (ret < 0) { 131661007b31SStefan Hajnoczi goto fail; 131761007b31SStefan Hajnoczi } 13189a4f4c31SKevin Wolf bdrv_debug_event(bs, BLKDBG_PWRITEV_RMW_AFTER_HEAD); 131961007b31SStefan Hajnoczi 132061007b31SStefan Hajnoczi qemu_iovec_init(&local_qiov, qiov->niov + 2); 132161007b31SStefan Hajnoczi qemu_iovec_add(&local_qiov, head_buf, offset & (align - 1)); 132261007b31SStefan Hajnoczi qemu_iovec_concat(&local_qiov, qiov, 0, qiov->size); 132361007b31SStefan Hajnoczi use_local_qiov = true; 132461007b31SStefan Hajnoczi 132561007b31SStefan Hajnoczi bytes += offset & (align - 1); 132661007b31SStefan Hajnoczi offset = offset & ~(align - 1); 132761007b31SStefan Hajnoczi } 132861007b31SStefan Hajnoczi 132961007b31SStefan Hajnoczi if ((offset + bytes) & (align - 1)) { 133061007b31SStefan Hajnoczi QEMUIOVector tail_qiov; 133161007b31SStefan Hajnoczi struct iovec tail_iov; 133261007b31SStefan Hajnoczi size_t tail_bytes; 133361007b31SStefan Hajnoczi bool waited; 133461007b31SStefan Hajnoczi 133561007b31SStefan Hajnoczi mark_request_serialising(&req, align); 133661007b31SStefan Hajnoczi waited = wait_serialising_requests(&req); 133761007b31SStefan Hajnoczi assert(!waited || !use_local_qiov); 133861007b31SStefan Hajnoczi 133961007b31SStefan Hajnoczi tail_buf = qemu_blockalign(bs, align); 134061007b31SStefan Hajnoczi tail_iov = (struct iovec) { 134161007b31SStefan Hajnoczi .iov_base = tail_buf, 134261007b31SStefan Hajnoczi .iov_len = align, 134361007b31SStefan Hajnoczi }; 134461007b31SStefan Hajnoczi qemu_iovec_init_external(&tail_qiov, &tail_iov, 1); 134561007b31SStefan Hajnoczi 13469a4f4c31SKevin Wolf bdrv_debug_event(bs, BLKDBG_PWRITEV_RMW_TAIL); 134761007b31SStefan Hajnoczi ret = bdrv_aligned_preadv(bs, &req, (offset + bytes) & ~(align - 1), align, 134861007b31SStefan Hajnoczi align, &tail_qiov, 0); 134961007b31SStefan Hajnoczi if (ret < 0) { 135061007b31SStefan Hajnoczi goto fail; 135161007b31SStefan Hajnoczi } 13529a4f4c31SKevin Wolf bdrv_debug_event(bs, BLKDBG_PWRITEV_RMW_AFTER_TAIL); 135361007b31SStefan Hajnoczi 135461007b31SStefan Hajnoczi if (!use_local_qiov) { 135561007b31SStefan Hajnoczi qemu_iovec_init(&local_qiov, qiov->niov + 1); 135661007b31SStefan Hajnoczi qemu_iovec_concat(&local_qiov, qiov, 0, qiov->size); 135761007b31SStefan Hajnoczi use_local_qiov = true; 135861007b31SStefan Hajnoczi } 135961007b31SStefan Hajnoczi 136061007b31SStefan Hajnoczi tail_bytes = (offset + bytes) & (align - 1); 136161007b31SStefan Hajnoczi qemu_iovec_add(&local_qiov, tail_buf + tail_bytes, align - tail_bytes); 136261007b31SStefan Hajnoczi 136361007b31SStefan Hajnoczi bytes = ROUND_UP(bytes, align); 136461007b31SStefan Hajnoczi } 136561007b31SStefan Hajnoczi 136661007b31SStefan Hajnoczi ret = bdrv_aligned_pwritev(bs, &req, offset, bytes, 136761007b31SStefan Hajnoczi use_local_qiov ? &local_qiov : qiov, 136861007b31SStefan Hajnoczi flags); 136961007b31SStefan Hajnoczi 137061007b31SStefan Hajnoczi fail: 137161007b31SStefan Hajnoczi 137261007b31SStefan Hajnoczi if (use_local_qiov) { 137361007b31SStefan Hajnoczi qemu_iovec_destroy(&local_qiov); 137461007b31SStefan Hajnoczi } 137561007b31SStefan Hajnoczi qemu_vfree(head_buf); 137661007b31SStefan Hajnoczi qemu_vfree(tail_buf); 13779eeb6dd1SFam Zheng out: 13789eeb6dd1SFam Zheng tracked_request_end(&req); 137961007b31SStefan Hajnoczi return ret; 138061007b31SStefan Hajnoczi } 138161007b31SStefan Hajnoczi 138261007b31SStefan Hajnoczi static int coroutine_fn bdrv_co_do_writev(BlockDriverState *bs, 138361007b31SStefan Hajnoczi int64_t sector_num, int nb_sectors, QEMUIOVector *qiov, 138461007b31SStefan Hajnoczi BdrvRequestFlags flags) 138561007b31SStefan Hajnoczi { 138661007b31SStefan Hajnoczi if (nb_sectors < 0 || nb_sectors > BDRV_REQUEST_MAX_SECTORS) { 138761007b31SStefan Hajnoczi return -EINVAL; 138861007b31SStefan Hajnoczi } 138961007b31SStefan Hajnoczi 139061007b31SStefan Hajnoczi return bdrv_co_do_pwritev(bs, sector_num << BDRV_SECTOR_BITS, 139161007b31SStefan Hajnoczi nb_sectors << BDRV_SECTOR_BITS, qiov, flags); 139261007b31SStefan Hajnoczi } 139361007b31SStefan Hajnoczi 139461007b31SStefan Hajnoczi int coroutine_fn bdrv_co_writev(BlockDriverState *bs, int64_t sector_num, 139561007b31SStefan Hajnoczi int nb_sectors, QEMUIOVector *qiov) 139661007b31SStefan Hajnoczi { 139761007b31SStefan Hajnoczi trace_bdrv_co_writev(bs, sector_num, nb_sectors); 139861007b31SStefan Hajnoczi 139961007b31SStefan Hajnoczi return bdrv_co_do_writev(bs, sector_num, nb_sectors, qiov, 0); 140061007b31SStefan Hajnoczi } 140161007b31SStefan Hajnoczi 140261007b31SStefan Hajnoczi int coroutine_fn bdrv_co_write_zeroes(BlockDriverState *bs, 140361007b31SStefan Hajnoczi int64_t sector_num, int nb_sectors, 140461007b31SStefan Hajnoczi BdrvRequestFlags flags) 140561007b31SStefan Hajnoczi { 140661007b31SStefan Hajnoczi trace_bdrv_co_write_zeroes(bs, sector_num, nb_sectors, flags); 140761007b31SStefan Hajnoczi 140861007b31SStefan Hajnoczi if (!(bs->open_flags & BDRV_O_UNMAP)) { 140961007b31SStefan Hajnoczi flags &= ~BDRV_REQ_MAY_UNMAP; 141061007b31SStefan Hajnoczi } 141161007b31SStefan Hajnoczi 1412d01c07f2SFam Zheng return bdrv_co_do_writev(bs, sector_num, nb_sectors, NULL, 141361007b31SStefan Hajnoczi BDRV_REQ_ZERO_WRITE | flags); 141461007b31SStefan Hajnoczi } 141561007b31SStefan Hajnoczi 141661007b31SStefan Hajnoczi int bdrv_flush_all(void) 141761007b31SStefan Hajnoczi { 141861007b31SStefan Hajnoczi BlockDriverState *bs = NULL; 141961007b31SStefan Hajnoczi int result = 0; 142061007b31SStefan Hajnoczi 142161007b31SStefan Hajnoczi while ((bs = bdrv_next(bs))) { 142261007b31SStefan Hajnoczi AioContext *aio_context = bdrv_get_aio_context(bs); 142361007b31SStefan Hajnoczi int ret; 142461007b31SStefan Hajnoczi 142561007b31SStefan Hajnoczi aio_context_acquire(aio_context); 142661007b31SStefan Hajnoczi ret = bdrv_flush(bs); 142761007b31SStefan Hajnoczi if (ret < 0 && !result) { 142861007b31SStefan Hajnoczi result = ret; 142961007b31SStefan Hajnoczi } 143061007b31SStefan Hajnoczi aio_context_release(aio_context); 143161007b31SStefan Hajnoczi } 143261007b31SStefan Hajnoczi 143361007b31SStefan Hajnoczi return result; 143461007b31SStefan Hajnoczi } 143561007b31SStefan Hajnoczi 143661007b31SStefan Hajnoczi typedef struct BdrvCoGetBlockStatusData { 143761007b31SStefan Hajnoczi BlockDriverState *bs; 143861007b31SStefan Hajnoczi BlockDriverState *base; 143961007b31SStefan Hajnoczi int64_t sector_num; 144061007b31SStefan Hajnoczi int nb_sectors; 144161007b31SStefan Hajnoczi int *pnum; 144261007b31SStefan Hajnoczi int64_t ret; 144361007b31SStefan Hajnoczi bool done; 144461007b31SStefan Hajnoczi } BdrvCoGetBlockStatusData; 144561007b31SStefan Hajnoczi 144661007b31SStefan Hajnoczi /* 144761007b31SStefan Hajnoczi * Returns the allocation status of the specified sectors. 144861007b31SStefan Hajnoczi * Drivers not implementing the functionality are assumed to not support 144961007b31SStefan Hajnoczi * backing files, hence all their sectors are reported as allocated. 145061007b31SStefan Hajnoczi * 145161007b31SStefan Hajnoczi * If 'sector_num' is beyond the end of the disk image the return value is 0 145261007b31SStefan Hajnoczi * and 'pnum' is set to 0. 145361007b31SStefan Hajnoczi * 145461007b31SStefan Hajnoczi * 'pnum' is set to the number of sectors (including and immediately following 145561007b31SStefan Hajnoczi * the specified sector) that are known to be in the same 145661007b31SStefan Hajnoczi * allocated/unallocated state. 145761007b31SStefan Hajnoczi * 145861007b31SStefan Hajnoczi * 'nb_sectors' is the max value 'pnum' should be set to. If nb_sectors goes 145961007b31SStefan Hajnoczi * beyond the end of the disk image it will be clamped. 146061007b31SStefan Hajnoczi */ 146161007b31SStefan Hajnoczi static int64_t coroutine_fn bdrv_co_get_block_status(BlockDriverState *bs, 146261007b31SStefan Hajnoczi int64_t sector_num, 146361007b31SStefan Hajnoczi int nb_sectors, int *pnum) 146461007b31SStefan Hajnoczi { 146561007b31SStefan Hajnoczi int64_t total_sectors; 146661007b31SStefan Hajnoczi int64_t n; 146761007b31SStefan Hajnoczi int64_t ret, ret2; 146861007b31SStefan Hajnoczi 146961007b31SStefan Hajnoczi total_sectors = bdrv_nb_sectors(bs); 147061007b31SStefan Hajnoczi if (total_sectors < 0) { 147161007b31SStefan Hajnoczi return total_sectors; 147261007b31SStefan Hajnoczi } 147361007b31SStefan Hajnoczi 147461007b31SStefan Hajnoczi if (sector_num >= total_sectors) { 147561007b31SStefan Hajnoczi *pnum = 0; 147661007b31SStefan Hajnoczi return 0; 147761007b31SStefan Hajnoczi } 147861007b31SStefan Hajnoczi 147961007b31SStefan Hajnoczi n = total_sectors - sector_num; 148061007b31SStefan Hajnoczi if (n < nb_sectors) { 148161007b31SStefan Hajnoczi nb_sectors = n; 148261007b31SStefan Hajnoczi } 148361007b31SStefan Hajnoczi 148461007b31SStefan Hajnoczi if (!bs->drv->bdrv_co_get_block_status) { 148561007b31SStefan Hajnoczi *pnum = nb_sectors; 148661007b31SStefan Hajnoczi ret = BDRV_BLOCK_DATA | BDRV_BLOCK_ALLOCATED; 148761007b31SStefan Hajnoczi if (bs->drv->protocol_name) { 148861007b31SStefan Hajnoczi ret |= BDRV_BLOCK_OFFSET_VALID | (sector_num * BDRV_SECTOR_SIZE); 148961007b31SStefan Hajnoczi } 149061007b31SStefan Hajnoczi return ret; 149161007b31SStefan Hajnoczi } 149261007b31SStefan Hajnoczi 149361007b31SStefan Hajnoczi ret = bs->drv->bdrv_co_get_block_status(bs, sector_num, nb_sectors, pnum); 149461007b31SStefan Hajnoczi if (ret < 0) { 149561007b31SStefan Hajnoczi *pnum = 0; 149661007b31SStefan Hajnoczi return ret; 149761007b31SStefan Hajnoczi } 149861007b31SStefan Hajnoczi 149961007b31SStefan Hajnoczi if (ret & BDRV_BLOCK_RAW) { 150061007b31SStefan Hajnoczi assert(ret & BDRV_BLOCK_OFFSET_VALID); 15019a4f4c31SKevin Wolf return bdrv_get_block_status(bs->file->bs, ret >> BDRV_SECTOR_BITS, 150261007b31SStefan Hajnoczi *pnum, pnum); 150361007b31SStefan Hajnoczi } 150461007b31SStefan Hajnoczi 150561007b31SStefan Hajnoczi if (ret & (BDRV_BLOCK_DATA | BDRV_BLOCK_ZERO)) { 150661007b31SStefan Hajnoczi ret |= BDRV_BLOCK_ALLOCATED; 1507a53f1a95SPaolo Bonzini } else { 150861007b31SStefan Hajnoczi if (bdrv_unallocated_blocks_are_zero(bs)) { 150961007b31SStefan Hajnoczi ret |= BDRV_BLOCK_ZERO; 1510760e0063SKevin Wolf } else if (bs->backing) { 1511760e0063SKevin Wolf BlockDriverState *bs2 = bs->backing->bs; 151261007b31SStefan Hajnoczi int64_t nb_sectors2 = bdrv_nb_sectors(bs2); 151361007b31SStefan Hajnoczi if (nb_sectors2 >= 0 && sector_num >= nb_sectors2) { 151461007b31SStefan Hajnoczi ret |= BDRV_BLOCK_ZERO; 151561007b31SStefan Hajnoczi } 151661007b31SStefan Hajnoczi } 151761007b31SStefan Hajnoczi } 151861007b31SStefan Hajnoczi 151961007b31SStefan Hajnoczi if (bs->file && 152061007b31SStefan Hajnoczi (ret & BDRV_BLOCK_DATA) && !(ret & BDRV_BLOCK_ZERO) && 152161007b31SStefan Hajnoczi (ret & BDRV_BLOCK_OFFSET_VALID)) { 152261007b31SStefan Hajnoczi int file_pnum; 152361007b31SStefan Hajnoczi 15249a4f4c31SKevin Wolf ret2 = bdrv_co_get_block_status(bs->file->bs, ret >> BDRV_SECTOR_BITS, 152561007b31SStefan Hajnoczi *pnum, &file_pnum); 152661007b31SStefan Hajnoczi if (ret2 >= 0) { 152761007b31SStefan Hajnoczi /* Ignore errors. This is just providing extra information, it 152861007b31SStefan Hajnoczi * is useful but not necessary. 152961007b31SStefan Hajnoczi */ 153061007b31SStefan Hajnoczi if (!file_pnum) { 153161007b31SStefan Hajnoczi /* !file_pnum indicates an offset at or beyond the EOF; it is 153261007b31SStefan Hajnoczi * perfectly valid for the format block driver to point to such 153361007b31SStefan Hajnoczi * offsets, so catch it and mark everything as zero */ 153461007b31SStefan Hajnoczi ret |= BDRV_BLOCK_ZERO; 153561007b31SStefan Hajnoczi } else { 153661007b31SStefan Hajnoczi /* Limit request to the range reported by the protocol driver */ 153761007b31SStefan Hajnoczi *pnum = file_pnum; 153861007b31SStefan Hajnoczi ret |= (ret2 & BDRV_BLOCK_ZERO); 153961007b31SStefan Hajnoczi } 154061007b31SStefan Hajnoczi } 154161007b31SStefan Hajnoczi } 154261007b31SStefan Hajnoczi 154361007b31SStefan Hajnoczi return ret; 154461007b31SStefan Hajnoczi } 154561007b31SStefan Hajnoczi 1546ba3f0e25SFam Zheng static int64_t coroutine_fn bdrv_co_get_block_status_above(BlockDriverState *bs, 1547ba3f0e25SFam Zheng BlockDriverState *base, 1548ba3f0e25SFam Zheng int64_t sector_num, 1549ba3f0e25SFam Zheng int nb_sectors, 1550ba3f0e25SFam Zheng int *pnum) 1551ba3f0e25SFam Zheng { 1552ba3f0e25SFam Zheng BlockDriverState *p; 1553ba3f0e25SFam Zheng int64_t ret = 0; 1554ba3f0e25SFam Zheng 1555ba3f0e25SFam Zheng assert(bs != base); 1556760e0063SKevin Wolf for (p = bs; p != base; p = backing_bs(p)) { 1557ba3f0e25SFam Zheng ret = bdrv_co_get_block_status(p, sector_num, nb_sectors, pnum); 1558ba3f0e25SFam Zheng if (ret < 0 || ret & BDRV_BLOCK_ALLOCATED) { 1559ba3f0e25SFam Zheng break; 1560ba3f0e25SFam Zheng } 1561ba3f0e25SFam Zheng /* [sector_num, pnum] unallocated on this layer, which could be only 1562ba3f0e25SFam Zheng * the first part of [sector_num, nb_sectors]. */ 1563ba3f0e25SFam Zheng nb_sectors = MIN(nb_sectors, *pnum); 1564ba3f0e25SFam Zheng } 1565ba3f0e25SFam Zheng return ret; 1566ba3f0e25SFam Zheng } 1567ba3f0e25SFam Zheng 1568ba3f0e25SFam Zheng /* Coroutine wrapper for bdrv_get_block_status_above() */ 1569ba3f0e25SFam Zheng static void coroutine_fn bdrv_get_block_status_above_co_entry(void *opaque) 157061007b31SStefan Hajnoczi { 157161007b31SStefan Hajnoczi BdrvCoGetBlockStatusData *data = opaque; 157261007b31SStefan Hajnoczi 1573ba3f0e25SFam Zheng data->ret = bdrv_co_get_block_status_above(data->bs, data->base, 1574ba3f0e25SFam Zheng data->sector_num, 1575ba3f0e25SFam Zheng data->nb_sectors, 157661007b31SStefan Hajnoczi data->pnum); 157761007b31SStefan Hajnoczi data->done = true; 157861007b31SStefan Hajnoczi } 157961007b31SStefan Hajnoczi 158061007b31SStefan Hajnoczi /* 1581ba3f0e25SFam Zheng * Synchronous wrapper around bdrv_co_get_block_status_above(). 158261007b31SStefan Hajnoczi * 1583ba3f0e25SFam Zheng * See bdrv_co_get_block_status_above() for details. 158461007b31SStefan Hajnoczi */ 1585ba3f0e25SFam Zheng int64_t bdrv_get_block_status_above(BlockDriverState *bs, 1586ba3f0e25SFam Zheng BlockDriverState *base, 1587ba3f0e25SFam Zheng int64_t sector_num, 158861007b31SStefan Hajnoczi int nb_sectors, int *pnum) 158961007b31SStefan Hajnoczi { 159061007b31SStefan Hajnoczi Coroutine *co; 159161007b31SStefan Hajnoczi BdrvCoGetBlockStatusData data = { 159261007b31SStefan Hajnoczi .bs = bs, 1593ba3f0e25SFam Zheng .base = base, 159461007b31SStefan Hajnoczi .sector_num = sector_num, 159561007b31SStefan Hajnoczi .nb_sectors = nb_sectors, 159661007b31SStefan Hajnoczi .pnum = pnum, 159761007b31SStefan Hajnoczi .done = false, 159861007b31SStefan Hajnoczi }; 159961007b31SStefan Hajnoczi 160061007b31SStefan Hajnoczi if (qemu_in_coroutine()) { 160161007b31SStefan Hajnoczi /* Fast-path if already in coroutine context */ 1602ba3f0e25SFam Zheng bdrv_get_block_status_above_co_entry(&data); 160361007b31SStefan Hajnoczi } else { 160461007b31SStefan Hajnoczi AioContext *aio_context = bdrv_get_aio_context(bs); 160561007b31SStefan Hajnoczi 1606ba3f0e25SFam Zheng co = qemu_coroutine_create(bdrv_get_block_status_above_co_entry); 160761007b31SStefan Hajnoczi qemu_coroutine_enter(co, &data); 160861007b31SStefan Hajnoczi while (!data.done) { 160961007b31SStefan Hajnoczi aio_poll(aio_context, true); 161061007b31SStefan Hajnoczi } 161161007b31SStefan Hajnoczi } 161261007b31SStefan Hajnoczi return data.ret; 161361007b31SStefan Hajnoczi } 161461007b31SStefan Hajnoczi 1615ba3f0e25SFam Zheng int64_t bdrv_get_block_status(BlockDriverState *bs, 1616ba3f0e25SFam Zheng int64_t sector_num, 1617ba3f0e25SFam Zheng int nb_sectors, int *pnum) 1618ba3f0e25SFam Zheng { 1619760e0063SKevin Wolf return bdrv_get_block_status_above(bs, backing_bs(bs), 1620ba3f0e25SFam Zheng sector_num, nb_sectors, pnum); 1621ba3f0e25SFam Zheng } 1622ba3f0e25SFam Zheng 162361007b31SStefan Hajnoczi int coroutine_fn bdrv_is_allocated(BlockDriverState *bs, int64_t sector_num, 162461007b31SStefan Hajnoczi int nb_sectors, int *pnum) 162561007b31SStefan Hajnoczi { 162661007b31SStefan Hajnoczi int64_t ret = bdrv_get_block_status(bs, sector_num, nb_sectors, pnum); 162761007b31SStefan Hajnoczi if (ret < 0) { 162861007b31SStefan Hajnoczi return ret; 162961007b31SStefan Hajnoczi } 163061007b31SStefan Hajnoczi return !!(ret & BDRV_BLOCK_ALLOCATED); 163161007b31SStefan Hajnoczi } 163261007b31SStefan Hajnoczi 163361007b31SStefan Hajnoczi /* 163461007b31SStefan Hajnoczi * Given an image chain: ... -> [BASE] -> [INTER1] -> [INTER2] -> [TOP] 163561007b31SStefan Hajnoczi * 163661007b31SStefan Hajnoczi * Return true if the given sector is allocated in any image between 163761007b31SStefan Hajnoczi * BASE and TOP (inclusive). BASE can be NULL to check if the given 163861007b31SStefan Hajnoczi * sector is allocated in any image of the chain. Return false otherwise. 163961007b31SStefan Hajnoczi * 164061007b31SStefan Hajnoczi * 'pnum' is set to the number of sectors (including and immediately following 164161007b31SStefan Hajnoczi * the specified sector) that are known to be in the same 164261007b31SStefan Hajnoczi * allocated/unallocated state. 164361007b31SStefan Hajnoczi * 164461007b31SStefan Hajnoczi */ 164561007b31SStefan Hajnoczi int bdrv_is_allocated_above(BlockDriverState *top, 164661007b31SStefan Hajnoczi BlockDriverState *base, 164761007b31SStefan Hajnoczi int64_t sector_num, 164861007b31SStefan Hajnoczi int nb_sectors, int *pnum) 164961007b31SStefan Hajnoczi { 165061007b31SStefan Hajnoczi BlockDriverState *intermediate; 165161007b31SStefan Hajnoczi int ret, n = nb_sectors; 165261007b31SStefan Hajnoczi 165361007b31SStefan Hajnoczi intermediate = top; 165461007b31SStefan Hajnoczi while (intermediate && intermediate != base) { 165561007b31SStefan Hajnoczi int pnum_inter; 165661007b31SStefan Hajnoczi ret = bdrv_is_allocated(intermediate, sector_num, nb_sectors, 165761007b31SStefan Hajnoczi &pnum_inter); 165861007b31SStefan Hajnoczi if (ret < 0) { 165961007b31SStefan Hajnoczi return ret; 166061007b31SStefan Hajnoczi } else if (ret) { 166161007b31SStefan Hajnoczi *pnum = pnum_inter; 166261007b31SStefan Hajnoczi return 1; 166361007b31SStefan Hajnoczi } 166461007b31SStefan Hajnoczi 166561007b31SStefan Hajnoczi /* 166661007b31SStefan Hajnoczi * [sector_num, nb_sectors] is unallocated on top but intermediate 166761007b31SStefan Hajnoczi * might have 166861007b31SStefan Hajnoczi * 166961007b31SStefan Hajnoczi * [sector_num+x, nr_sectors] allocated. 167061007b31SStefan Hajnoczi */ 167161007b31SStefan Hajnoczi if (n > pnum_inter && 167261007b31SStefan Hajnoczi (intermediate == top || 167361007b31SStefan Hajnoczi sector_num + pnum_inter < intermediate->total_sectors)) { 167461007b31SStefan Hajnoczi n = pnum_inter; 167561007b31SStefan Hajnoczi } 167661007b31SStefan Hajnoczi 1677760e0063SKevin Wolf intermediate = backing_bs(intermediate); 167861007b31SStefan Hajnoczi } 167961007b31SStefan Hajnoczi 168061007b31SStefan Hajnoczi *pnum = n; 168161007b31SStefan Hajnoczi return 0; 168261007b31SStefan Hajnoczi } 168361007b31SStefan Hajnoczi 168461007b31SStefan Hajnoczi int bdrv_write_compressed(BlockDriverState *bs, int64_t sector_num, 168561007b31SStefan Hajnoczi const uint8_t *buf, int nb_sectors) 168661007b31SStefan Hajnoczi { 168761007b31SStefan Hajnoczi BlockDriver *drv = bs->drv; 168861007b31SStefan Hajnoczi int ret; 168961007b31SStefan Hajnoczi 169061007b31SStefan Hajnoczi if (!drv) { 169161007b31SStefan Hajnoczi return -ENOMEDIUM; 169261007b31SStefan Hajnoczi } 169361007b31SStefan Hajnoczi if (!drv->bdrv_write_compressed) { 169461007b31SStefan Hajnoczi return -ENOTSUP; 169561007b31SStefan Hajnoczi } 169661007b31SStefan Hajnoczi ret = bdrv_check_request(bs, sector_num, nb_sectors); 169761007b31SStefan Hajnoczi if (ret < 0) { 169861007b31SStefan Hajnoczi return ret; 169961007b31SStefan Hajnoczi } 170061007b31SStefan Hajnoczi 170161007b31SStefan Hajnoczi assert(QLIST_EMPTY(&bs->dirty_bitmaps)); 170261007b31SStefan Hajnoczi 170361007b31SStefan Hajnoczi return drv->bdrv_write_compressed(bs, sector_num, buf, nb_sectors); 170461007b31SStefan Hajnoczi } 170561007b31SStefan Hajnoczi 170661007b31SStefan Hajnoczi int bdrv_save_vmstate(BlockDriverState *bs, const uint8_t *buf, 170761007b31SStefan Hajnoczi int64_t pos, int size) 170861007b31SStefan Hajnoczi { 170961007b31SStefan Hajnoczi QEMUIOVector qiov; 171061007b31SStefan Hajnoczi struct iovec iov = { 171161007b31SStefan Hajnoczi .iov_base = (void *) buf, 171261007b31SStefan Hajnoczi .iov_len = size, 171361007b31SStefan Hajnoczi }; 171461007b31SStefan Hajnoczi 171561007b31SStefan Hajnoczi qemu_iovec_init_external(&qiov, &iov, 1); 171661007b31SStefan Hajnoczi return bdrv_writev_vmstate(bs, &qiov, pos); 171761007b31SStefan Hajnoczi } 171861007b31SStefan Hajnoczi 171961007b31SStefan Hajnoczi int bdrv_writev_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos) 172061007b31SStefan Hajnoczi { 172161007b31SStefan Hajnoczi BlockDriver *drv = bs->drv; 172261007b31SStefan Hajnoczi 172361007b31SStefan Hajnoczi if (!drv) { 172461007b31SStefan Hajnoczi return -ENOMEDIUM; 172561007b31SStefan Hajnoczi } else if (drv->bdrv_save_vmstate) { 172661007b31SStefan Hajnoczi return drv->bdrv_save_vmstate(bs, qiov, pos); 172761007b31SStefan Hajnoczi } else if (bs->file) { 17289a4f4c31SKevin Wolf return bdrv_writev_vmstate(bs->file->bs, qiov, pos); 172961007b31SStefan Hajnoczi } 173061007b31SStefan Hajnoczi 173161007b31SStefan Hajnoczi return -ENOTSUP; 173261007b31SStefan Hajnoczi } 173361007b31SStefan Hajnoczi 173461007b31SStefan Hajnoczi int bdrv_load_vmstate(BlockDriverState *bs, uint8_t *buf, 173561007b31SStefan Hajnoczi int64_t pos, int size) 173661007b31SStefan Hajnoczi { 173761007b31SStefan Hajnoczi BlockDriver *drv = bs->drv; 173861007b31SStefan Hajnoczi if (!drv) 173961007b31SStefan Hajnoczi return -ENOMEDIUM; 174061007b31SStefan Hajnoczi if (drv->bdrv_load_vmstate) 174161007b31SStefan Hajnoczi return drv->bdrv_load_vmstate(bs, buf, pos, size); 174261007b31SStefan Hajnoczi if (bs->file) 17439a4f4c31SKevin Wolf return bdrv_load_vmstate(bs->file->bs, buf, pos, size); 174461007b31SStefan Hajnoczi return -ENOTSUP; 174561007b31SStefan Hajnoczi } 174661007b31SStefan Hajnoczi 174761007b31SStefan Hajnoczi /**************************************************************/ 174861007b31SStefan Hajnoczi /* async I/Os */ 174961007b31SStefan Hajnoczi 175061007b31SStefan Hajnoczi BlockAIOCB *bdrv_aio_readv(BlockDriverState *bs, int64_t sector_num, 175161007b31SStefan Hajnoczi QEMUIOVector *qiov, int nb_sectors, 175261007b31SStefan Hajnoczi BlockCompletionFunc *cb, void *opaque) 175361007b31SStefan Hajnoczi { 175461007b31SStefan Hajnoczi trace_bdrv_aio_readv(bs, sector_num, nb_sectors, opaque); 175561007b31SStefan Hajnoczi 175661007b31SStefan Hajnoczi return bdrv_co_aio_rw_vector(bs, sector_num, qiov, nb_sectors, 0, 175761007b31SStefan Hajnoczi cb, opaque, false); 175861007b31SStefan Hajnoczi } 175961007b31SStefan Hajnoczi 176061007b31SStefan Hajnoczi BlockAIOCB *bdrv_aio_writev(BlockDriverState *bs, int64_t sector_num, 176161007b31SStefan Hajnoczi QEMUIOVector *qiov, int nb_sectors, 176261007b31SStefan Hajnoczi BlockCompletionFunc *cb, void *opaque) 176361007b31SStefan Hajnoczi { 176461007b31SStefan Hajnoczi trace_bdrv_aio_writev(bs, sector_num, nb_sectors, opaque); 176561007b31SStefan Hajnoczi 176661007b31SStefan Hajnoczi return bdrv_co_aio_rw_vector(bs, sector_num, qiov, nb_sectors, 0, 176761007b31SStefan Hajnoczi cb, opaque, true); 176861007b31SStefan Hajnoczi } 176961007b31SStefan Hajnoczi 177061007b31SStefan Hajnoczi BlockAIOCB *bdrv_aio_write_zeroes(BlockDriverState *bs, 177161007b31SStefan Hajnoczi int64_t sector_num, int nb_sectors, BdrvRequestFlags flags, 177261007b31SStefan Hajnoczi BlockCompletionFunc *cb, void *opaque) 177361007b31SStefan Hajnoczi { 177461007b31SStefan Hajnoczi trace_bdrv_aio_write_zeroes(bs, sector_num, nb_sectors, flags, opaque); 177561007b31SStefan Hajnoczi 177661007b31SStefan Hajnoczi return bdrv_co_aio_rw_vector(bs, sector_num, NULL, nb_sectors, 177761007b31SStefan Hajnoczi BDRV_REQ_ZERO_WRITE | flags, 177861007b31SStefan Hajnoczi cb, opaque, true); 177961007b31SStefan Hajnoczi } 178061007b31SStefan Hajnoczi 178161007b31SStefan Hajnoczi 178261007b31SStefan Hajnoczi typedef struct MultiwriteCB { 178361007b31SStefan Hajnoczi int error; 178461007b31SStefan Hajnoczi int num_requests; 178561007b31SStefan Hajnoczi int num_callbacks; 178661007b31SStefan Hajnoczi struct { 178761007b31SStefan Hajnoczi BlockCompletionFunc *cb; 178861007b31SStefan Hajnoczi void *opaque; 178961007b31SStefan Hajnoczi QEMUIOVector *free_qiov; 179061007b31SStefan Hajnoczi } callbacks[]; 179161007b31SStefan Hajnoczi } MultiwriteCB; 179261007b31SStefan Hajnoczi 179361007b31SStefan Hajnoczi static void multiwrite_user_cb(MultiwriteCB *mcb) 179461007b31SStefan Hajnoczi { 179561007b31SStefan Hajnoczi int i; 179661007b31SStefan Hajnoczi 179761007b31SStefan Hajnoczi for (i = 0; i < mcb->num_callbacks; i++) { 179861007b31SStefan Hajnoczi mcb->callbacks[i].cb(mcb->callbacks[i].opaque, mcb->error); 179961007b31SStefan Hajnoczi if (mcb->callbacks[i].free_qiov) { 180061007b31SStefan Hajnoczi qemu_iovec_destroy(mcb->callbacks[i].free_qiov); 180161007b31SStefan Hajnoczi } 180261007b31SStefan Hajnoczi g_free(mcb->callbacks[i].free_qiov); 180361007b31SStefan Hajnoczi } 180461007b31SStefan Hajnoczi } 180561007b31SStefan Hajnoczi 180661007b31SStefan Hajnoczi static void multiwrite_cb(void *opaque, int ret) 180761007b31SStefan Hajnoczi { 180861007b31SStefan Hajnoczi MultiwriteCB *mcb = opaque; 180961007b31SStefan Hajnoczi 181061007b31SStefan Hajnoczi trace_multiwrite_cb(mcb, ret); 181161007b31SStefan Hajnoczi 181261007b31SStefan Hajnoczi if (ret < 0 && !mcb->error) { 181361007b31SStefan Hajnoczi mcb->error = ret; 181461007b31SStefan Hajnoczi } 181561007b31SStefan Hajnoczi 181661007b31SStefan Hajnoczi mcb->num_requests--; 181761007b31SStefan Hajnoczi if (mcb->num_requests == 0) { 181861007b31SStefan Hajnoczi multiwrite_user_cb(mcb); 181961007b31SStefan Hajnoczi g_free(mcb); 182061007b31SStefan Hajnoczi } 182161007b31SStefan Hajnoczi } 182261007b31SStefan Hajnoczi 182361007b31SStefan Hajnoczi static int multiwrite_req_compare(const void *a, const void *b) 182461007b31SStefan Hajnoczi { 182561007b31SStefan Hajnoczi const BlockRequest *req1 = a, *req2 = b; 182661007b31SStefan Hajnoczi 182761007b31SStefan Hajnoczi /* 182861007b31SStefan Hajnoczi * Note that we can't simply subtract req2->sector from req1->sector 182961007b31SStefan Hajnoczi * here as that could overflow the return value. 183061007b31SStefan Hajnoczi */ 183161007b31SStefan Hajnoczi if (req1->sector > req2->sector) { 183261007b31SStefan Hajnoczi return 1; 183361007b31SStefan Hajnoczi } else if (req1->sector < req2->sector) { 183461007b31SStefan Hajnoczi return -1; 183561007b31SStefan Hajnoczi } else { 183661007b31SStefan Hajnoczi return 0; 183761007b31SStefan Hajnoczi } 183861007b31SStefan Hajnoczi } 183961007b31SStefan Hajnoczi 184061007b31SStefan Hajnoczi /* 184161007b31SStefan Hajnoczi * Takes a bunch of requests and tries to merge them. Returns the number of 184261007b31SStefan Hajnoczi * requests that remain after merging. 184361007b31SStefan Hajnoczi */ 184461007b31SStefan Hajnoczi static int multiwrite_merge(BlockDriverState *bs, BlockRequest *reqs, 184561007b31SStefan Hajnoczi int num_reqs, MultiwriteCB *mcb) 184661007b31SStefan Hajnoczi { 184761007b31SStefan Hajnoczi int i, outidx; 184861007b31SStefan Hajnoczi 184961007b31SStefan Hajnoczi // Sort requests by start sector 185061007b31SStefan Hajnoczi qsort(reqs, num_reqs, sizeof(*reqs), &multiwrite_req_compare); 185161007b31SStefan Hajnoczi 185261007b31SStefan Hajnoczi // Check if adjacent requests touch the same clusters. If so, combine them, 185361007b31SStefan Hajnoczi // filling up gaps with zero sectors. 185461007b31SStefan Hajnoczi outidx = 0; 185561007b31SStefan Hajnoczi for (i = 1; i < num_reqs; i++) { 185661007b31SStefan Hajnoczi int merge = 0; 185761007b31SStefan Hajnoczi int64_t oldreq_last = reqs[outidx].sector + reqs[outidx].nb_sectors; 185861007b31SStefan Hajnoczi 185961007b31SStefan Hajnoczi // Handle exactly sequential writes and overlapping writes. 186061007b31SStefan Hajnoczi if (reqs[i].sector <= oldreq_last) { 186161007b31SStefan Hajnoczi merge = 1; 186261007b31SStefan Hajnoczi } 186361007b31SStefan Hajnoczi 186461007b31SStefan Hajnoczi if (reqs[outidx].qiov->niov + reqs[i].qiov->niov + 1 > IOV_MAX) { 186561007b31SStefan Hajnoczi merge = 0; 186661007b31SStefan Hajnoczi } 186761007b31SStefan Hajnoczi 186861007b31SStefan Hajnoczi if (bs->bl.max_transfer_length && reqs[outidx].nb_sectors + 186961007b31SStefan Hajnoczi reqs[i].nb_sectors > bs->bl.max_transfer_length) { 187061007b31SStefan Hajnoczi merge = 0; 187161007b31SStefan Hajnoczi } 187261007b31SStefan Hajnoczi 187361007b31SStefan Hajnoczi if (merge) { 187461007b31SStefan Hajnoczi size_t size; 187561007b31SStefan Hajnoczi QEMUIOVector *qiov = g_malloc0(sizeof(*qiov)); 187661007b31SStefan Hajnoczi qemu_iovec_init(qiov, 187761007b31SStefan Hajnoczi reqs[outidx].qiov->niov + reqs[i].qiov->niov + 1); 187861007b31SStefan Hajnoczi 187961007b31SStefan Hajnoczi // Add the first request to the merged one. If the requests are 188061007b31SStefan Hajnoczi // overlapping, drop the last sectors of the first request. 188161007b31SStefan Hajnoczi size = (reqs[i].sector - reqs[outidx].sector) << 9; 188261007b31SStefan Hajnoczi qemu_iovec_concat(qiov, reqs[outidx].qiov, 0, size); 188361007b31SStefan Hajnoczi 188461007b31SStefan Hajnoczi // We should need to add any zeros between the two requests 188561007b31SStefan Hajnoczi assert (reqs[i].sector <= oldreq_last); 188661007b31SStefan Hajnoczi 188761007b31SStefan Hajnoczi // Add the second request 188861007b31SStefan Hajnoczi qemu_iovec_concat(qiov, reqs[i].qiov, 0, reqs[i].qiov->size); 188961007b31SStefan Hajnoczi 189061007b31SStefan Hajnoczi // Add tail of first request, if necessary 189161007b31SStefan Hajnoczi if (qiov->size < reqs[outidx].qiov->size) { 189261007b31SStefan Hajnoczi qemu_iovec_concat(qiov, reqs[outidx].qiov, qiov->size, 189361007b31SStefan Hajnoczi reqs[outidx].qiov->size - qiov->size); 189461007b31SStefan Hajnoczi } 189561007b31SStefan Hajnoczi 189661007b31SStefan Hajnoczi reqs[outidx].nb_sectors = qiov->size >> 9; 189761007b31SStefan Hajnoczi reqs[outidx].qiov = qiov; 189861007b31SStefan Hajnoczi 189961007b31SStefan Hajnoczi mcb->callbacks[i].free_qiov = reqs[outidx].qiov; 190061007b31SStefan Hajnoczi } else { 190161007b31SStefan Hajnoczi outidx++; 190261007b31SStefan Hajnoczi reqs[outidx].sector = reqs[i].sector; 190361007b31SStefan Hajnoczi reqs[outidx].nb_sectors = reqs[i].nb_sectors; 190461007b31SStefan Hajnoczi reqs[outidx].qiov = reqs[i].qiov; 190561007b31SStefan Hajnoczi } 190661007b31SStefan Hajnoczi } 190761007b31SStefan Hajnoczi 190861007b31SStefan Hajnoczi block_acct_merge_done(&bs->stats, BLOCK_ACCT_WRITE, num_reqs - outidx - 1); 190961007b31SStefan Hajnoczi 191061007b31SStefan Hajnoczi return outidx + 1; 191161007b31SStefan Hajnoczi } 191261007b31SStefan Hajnoczi 191361007b31SStefan Hajnoczi /* 191461007b31SStefan Hajnoczi * Submit multiple AIO write requests at once. 191561007b31SStefan Hajnoczi * 191661007b31SStefan Hajnoczi * On success, the function returns 0 and all requests in the reqs array have 191761007b31SStefan Hajnoczi * been submitted. In error case this function returns -1, and any of the 191861007b31SStefan Hajnoczi * requests may or may not be submitted yet. In particular, this means that the 191961007b31SStefan Hajnoczi * callback will be called for some of the requests, for others it won't. The 192061007b31SStefan Hajnoczi * caller must check the error field of the BlockRequest to wait for the right 192161007b31SStefan Hajnoczi * callbacks (if error != 0, no callback will be called). 192261007b31SStefan Hajnoczi * 192361007b31SStefan Hajnoczi * The implementation may modify the contents of the reqs array, e.g. to merge 192461007b31SStefan Hajnoczi * requests. However, the fields opaque and error are left unmodified as they 192561007b31SStefan Hajnoczi * are used to signal failure for a single request to the caller. 192661007b31SStefan Hajnoczi */ 192761007b31SStefan Hajnoczi int bdrv_aio_multiwrite(BlockDriverState *bs, BlockRequest *reqs, int num_reqs) 192861007b31SStefan Hajnoczi { 192961007b31SStefan Hajnoczi MultiwriteCB *mcb; 193061007b31SStefan Hajnoczi int i; 193161007b31SStefan Hajnoczi 193261007b31SStefan Hajnoczi /* don't submit writes if we don't have a medium */ 193361007b31SStefan Hajnoczi if (bs->drv == NULL) { 193461007b31SStefan Hajnoczi for (i = 0; i < num_reqs; i++) { 193561007b31SStefan Hajnoczi reqs[i].error = -ENOMEDIUM; 193661007b31SStefan Hajnoczi } 193761007b31SStefan Hajnoczi return -1; 193861007b31SStefan Hajnoczi } 193961007b31SStefan Hajnoczi 194061007b31SStefan Hajnoczi if (num_reqs == 0) { 194161007b31SStefan Hajnoczi return 0; 194261007b31SStefan Hajnoczi } 194361007b31SStefan Hajnoczi 194461007b31SStefan Hajnoczi // Create MultiwriteCB structure 194561007b31SStefan Hajnoczi mcb = g_malloc0(sizeof(*mcb) + num_reqs * sizeof(*mcb->callbacks)); 194661007b31SStefan Hajnoczi mcb->num_requests = 0; 194761007b31SStefan Hajnoczi mcb->num_callbacks = num_reqs; 194861007b31SStefan Hajnoczi 194961007b31SStefan Hajnoczi for (i = 0; i < num_reqs; i++) { 195061007b31SStefan Hajnoczi mcb->callbacks[i].cb = reqs[i].cb; 195161007b31SStefan Hajnoczi mcb->callbacks[i].opaque = reqs[i].opaque; 195261007b31SStefan Hajnoczi } 195361007b31SStefan Hajnoczi 195461007b31SStefan Hajnoczi // Check for mergable requests 195561007b31SStefan Hajnoczi num_reqs = multiwrite_merge(bs, reqs, num_reqs, mcb); 195661007b31SStefan Hajnoczi 195761007b31SStefan Hajnoczi trace_bdrv_aio_multiwrite(mcb, mcb->num_callbacks, num_reqs); 195861007b31SStefan Hajnoczi 195961007b31SStefan Hajnoczi /* Run the aio requests. */ 196061007b31SStefan Hajnoczi mcb->num_requests = num_reqs; 196161007b31SStefan Hajnoczi for (i = 0; i < num_reqs; i++) { 196261007b31SStefan Hajnoczi bdrv_co_aio_rw_vector(bs, reqs[i].sector, reqs[i].qiov, 196361007b31SStefan Hajnoczi reqs[i].nb_sectors, reqs[i].flags, 196461007b31SStefan Hajnoczi multiwrite_cb, mcb, 196561007b31SStefan Hajnoczi true); 196661007b31SStefan Hajnoczi } 196761007b31SStefan Hajnoczi 196861007b31SStefan Hajnoczi return 0; 196961007b31SStefan Hajnoczi } 197061007b31SStefan Hajnoczi 197161007b31SStefan Hajnoczi void bdrv_aio_cancel(BlockAIOCB *acb) 197261007b31SStefan Hajnoczi { 197361007b31SStefan Hajnoczi qemu_aio_ref(acb); 197461007b31SStefan Hajnoczi bdrv_aio_cancel_async(acb); 197561007b31SStefan Hajnoczi while (acb->refcnt > 1) { 197661007b31SStefan Hajnoczi if (acb->aiocb_info->get_aio_context) { 197761007b31SStefan Hajnoczi aio_poll(acb->aiocb_info->get_aio_context(acb), true); 197861007b31SStefan Hajnoczi } else if (acb->bs) { 197961007b31SStefan Hajnoczi aio_poll(bdrv_get_aio_context(acb->bs), true); 198061007b31SStefan Hajnoczi } else { 198161007b31SStefan Hajnoczi abort(); 198261007b31SStefan Hajnoczi } 198361007b31SStefan Hajnoczi } 198461007b31SStefan Hajnoczi qemu_aio_unref(acb); 198561007b31SStefan Hajnoczi } 198661007b31SStefan Hajnoczi 198761007b31SStefan Hajnoczi /* Async version of aio cancel. The caller is not blocked if the acb implements 198861007b31SStefan Hajnoczi * cancel_async, otherwise we do nothing and let the request normally complete. 198961007b31SStefan Hajnoczi * In either case the completion callback must be called. */ 199061007b31SStefan Hajnoczi void bdrv_aio_cancel_async(BlockAIOCB *acb) 199161007b31SStefan Hajnoczi { 199261007b31SStefan Hajnoczi if (acb->aiocb_info->cancel_async) { 199361007b31SStefan Hajnoczi acb->aiocb_info->cancel_async(acb); 199461007b31SStefan Hajnoczi } 199561007b31SStefan Hajnoczi } 199661007b31SStefan Hajnoczi 199761007b31SStefan Hajnoczi /**************************************************************/ 199861007b31SStefan Hajnoczi /* async block device emulation */ 199961007b31SStefan Hajnoczi 200061007b31SStefan Hajnoczi typedef struct BlockAIOCBSync { 200161007b31SStefan Hajnoczi BlockAIOCB common; 200261007b31SStefan Hajnoczi QEMUBH *bh; 200361007b31SStefan Hajnoczi int ret; 200461007b31SStefan Hajnoczi /* vector translation state */ 200561007b31SStefan Hajnoczi QEMUIOVector *qiov; 200661007b31SStefan Hajnoczi uint8_t *bounce; 200761007b31SStefan Hajnoczi int is_write; 200861007b31SStefan Hajnoczi } BlockAIOCBSync; 200961007b31SStefan Hajnoczi 201061007b31SStefan Hajnoczi static const AIOCBInfo bdrv_em_aiocb_info = { 201161007b31SStefan Hajnoczi .aiocb_size = sizeof(BlockAIOCBSync), 201261007b31SStefan Hajnoczi }; 201361007b31SStefan Hajnoczi 201461007b31SStefan Hajnoczi static void bdrv_aio_bh_cb(void *opaque) 201561007b31SStefan Hajnoczi { 201661007b31SStefan Hajnoczi BlockAIOCBSync *acb = opaque; 201761007b31SStefan Hajnoczi 201861007b31SStefan Hajnoczi if (!acb->is_write && acb->ret >= 0) { 201961007b31SStefan Hajnoczi qemu_iovec_from_buf(acb->qiov, 0, acb->bounce, acb->qiov->size); 202061007b31SStefan Hajnoczi } 202161007b31SStefan Hajnoczi qemu_vfree(acb->bounce); 202261007b31SStefan Hajnoczi acb->common.cb(acb->common.opaque, acb->ret); 202361007b31SStefan Hajnoczi qemu_bh_delete(acb->bh); 202461007b31SStefan Hajnoczi acb->bh = NULL; 202561007b31SStefan Hajnoczi qemu_aio_unref(acb); 202661007b31SStefan Hajnoczi } 202761007b31SStefan Hajnoczi 202861007b31SStefan Hajnoczi static BlockAIOCB *bdrv_aio_rw_vector(BlockDriverState *bs, 202961007b31SStefan Hajnoczi int64_t sector_num, 203061007b31SStefan Hajnoczi QEMUIOVector *qiov, 203161007b31SStefan Hajnoczi int nb_sectors, 203261007b31SStefan Hajnoczi BlockCompletionFunc *cb, 203361007b31SStefan Hajnoczi void *opaque, 203461007b31SStefan Hajnoczi int is_write) 203561007b31SStefan Hajnoczi 203661007b31SStefan Hajnoczi { 203761007b31SStefan Hajnoczi BlockAIOCBSync *acb; 203861007b31SStefan Hajnoczi 203961007b31SStefan Hajnoczi acb = qemu_aio_get(&bdrv_em_aiocb_info, bs, cb, opaque); 204061007b31SStefan Hajnoczi acb->is_write = is_write; 204161007b31SStefan Hajnoczi acb->qiov = qiov; 204261007b31SStefan Hajnoczi acb->bounce = qemu_try_blockalign(bs, qiov->size); 204361007b31SStefan Hajnoczi acb->bh = aio_bh_new(bdrv_get_aio_context(bs), bdrv_aio_bh_cb, acb); 204461007b31SStefan Hajnoczi 204561007b31SStefan Hajnoczi if (acb->bounce == NULL) { 204661007b31SStefan Hajnoczi acb->ret = -ENOMEM; 204761007b31SStefan Hajnoczi } else if (is_write) { 204861007b31SStefan Hajnoczi qemu_iovec_to_buf(acb->qiov, 0, acb->bounce, qiov->size); 204961007b31SStefan Hajnoczi acb->ret = bs->drv->bdrv_write(bs, sector_num, acb->bounce, nb_sectors); 205061007b31SStefan Hajnoczi } else { 205161007b31SStefan Hajnoczi acb->ret = bs->drv->bdrv_read(bs, sector_num, acb->bounce, nb_sectors); 205261007b31SStefan Hajnoczi } 205361007b31SStefan Hajnoczi 205461007b31SStefan Hajnoczi qemu_bh_schedule(acb->bh); 205561007b31SStefan Hajnoczi 205661007b31SStefan Hajnoczi return &acb->common; 205761007b31SStefan Hajnoczi } 205861007b31SStefan Hajnoczi 205961007b31SStefan Hajnoczi static BlockAIOCB *bdrv_aio_readv_em(BlockDriverState *bs, 206061007b31SStefan Hajnoczi int64_t sector_num, QEMUIOVector *qiov, int nb_sectors, 206161007b31SStefan Hajnoczi BlockCompletionFunc *cb, void *opaque) 206261007b31SStefan Hajnoczi { 206361007b31SStefan Hajnoczi return bdrv_aio_rw_vector(bs, sector_num, qiov, nb_sectors, cb, opaque, 0); 206461007b31SStefan Hajnoczi } 206561007b31SStefan Hajnoczi 206661007b31SStefan Hajnoczi static BlockAIOCB *bdrv_aio_writev_em(BlockDriverState *bs, 206761007b31SStefan Hajnoczi int64_t sector_num, QEMUIOVector *qiov, int nb_sectors, 206861007b31SStefan Hajnoczi BlockCompletionFunc *cb, void *opaque) 206961007b31SStefan Hajnoczi { 207061007b31SStefan Hajnoczi return bdrv_aio_rw_vector(bs, sector_num, qiov, nb_sectors, cb, opaque, 1); 207161007b31SStefan Hajnoczi } 207261007b31SStefan Hajnoczi 207361007b31SStefan Hajnoczi 207461007b31SStefan Hajnoczi typedef struct BlockAIOCBCoroutine { 207561007b31SStefan Hajnoczi BlockAIOCB common; 207661007b31SStefan Hajnoczi BlockRequest req; 207761007b31SStefan Hajnoczi bool is_write; 207861007b31SStefan Hajnoczi bool need_bh; 207961007b31SStefan Hajnoczi bool *done; 208061007b31SStefan Hajnoczi QEMUBH* bh; 208161007b31SStefan Hajnoczi } BlockAIOCBCoroutine; 208261007b31SStefan Hajnoczi 208361007b31SStefan Hajnoczi static const AIOCBInfo bdrv_em_co_aiocb_info = { 208461007b31SStefan Hajnoczi .aiocb_size = sizeof(BlockAIOCBCoroutine), 208561007b31SStefan Hajnoczi }; 208661007b31SStefan Hajnoczi 208761007b31SStefan Hajnoczi static void bdrv_co_complete(BlockAIOCBCoroutine *acb) 208861007b31SStefan Hajnoczi { 208961007b31SStefan Hajnoczi if (!acb->need_bh) { 209061007b31SStefan Hajnoczi acb->common.cb(acb->common.opaque, acb->req.error); 209161007b31SStefan Hajnoczi qemu_aio_unref(acb); 209261007b31SStefan Hajnoczi } 209361007b31SStefan Hajnoczi } 209461007b31SStefan Hajnoczi 209561007b31SStefan Hajnoczi static void bdrv_co_em_bh(void *opaque) 209661007b31SStefan Hajnoczi { 209761007b31SStefan Hajnoczi BlockAIOCBCoroutine *acb = opaque; 209861007b31SStefan Hajnoczi 209961007b31SStefan Hajnoczi assert(!acb->need_bh); 210061007b31SStefan Hajnoczi qemu_bh_delete(acb->bh); 210161007b31SStefan Hajnoczi bdrv_co_complete(acb); 210261007b31SStefan Hajnoczi } 210361007b31SStefan Hajnoczi 210461007b31SStefan Hajnoczi static void bdrv_co_maybe_schedule_bh(BlockAIOCBCoroutine *acb) 210561007b31SStefan Hajnoczi { 210661007b31SStefan Hajnoczi acb->need_bh = false; 210761007b31SStefan Hajnoczi if (acb->req.error != -EINPROGRESS) { 210861007b31SStefan Hajnoczi BlockDriverState *bs = acb->common.bs; 210961007b31SStefan Hajnoczi 211061007b31SStefan Hajnoczi acb->bh = aio_bh_new(bdrv_get_aio_context(bs), bdrv_co_em_bh, acb); 211161007b31SStefan Hajnoczi qemu_bh_schedule(acb->bh); 211261007b31SStefan Hajnoczi } 211361007b31SStefan Hajnoczi } 211461007b31SStefan Hajnoczi 211561007b31SStefan Hajnoczi /* Invoke bdrv_co_do_readv/bdrv_co_do_writev */ 211661007b31SStefan Hajnoczi static void coroutine_fn bdrv_co_do_rw(void *opaque) 211761007b31SStefan Hajnoczi { 211861007b31SStefan Hajnoczi BlockAIOCBCoroutine *acb = opaque; 211961007b31SStefan Hajnoczi BlockDriverState *bs = acb->common.bs; 212061007b31SStefan Hajnoczi 212161007b31SStefan Hajnoczi if (!acb->is_write) { 212261007b31SStefan Hajnoczi acb->req.error = bdrv_co_do_readv(bs, acb->req.sector, 212361007b31SStefan Hajnoczi acb->req.nb_sectors, acb->req.qiov, acb->req.flags); 212461007b31SStefan Hajnoczi } else { 212561007b31SStefan Hajnoczi acb->req.error = bdrv_co_do_writev(bs, acb->req.sector, 212661007b31SStefan Hajnoczi acb->req.nb_sectors, acb->req.qiov, acb->req.flags); 212761007b31SStefan Hajnoczi } 212861007b31SStefan Hajnoczi 212961007b31SStefan Hajnoczi bdrv_co_complete(acb); 213061007b31SStefan Hajnoczi } 213161007b31SStefan Hajnoczi 213261007b31SStefan Hajnoczi static BlockAIOCB *bdrv_co_aio_rw_vector(BlockDriverState *bs, 213361007b31SStefan Hajnoczi int64_t sector_num, 213461007b31SStefan Hajnoczi QEMUIOVector *qiov, 213561007b31SStefan Hajnoczi int nb_sectors, 213661007b31SStefan Hajnoczi BdrvRequestFlags flags, 213761007b31SStefan Hajnoczi BlockCompletionFunc *cb, 213861007b31SStefan Hajnoczi void *opaque, 213961007b31SStefan Hajnoczi bool is_write) 214061007b31SStefan Hajnoczi { 214161007b31SStefan Hajnoczi Coroutine *co; 214261007b31SStefan Hajnoczi BlockAIOCBCoroutine *acb; 214361007b31SStefan Hajnoczi 214461007b31SStefan Hajnoczi acb = qemu_aio_get(&bdrv_em_co_aiocb_info, bs, cb, opaque); 214561007b31SStefan Hajnoczi acb->need_bh = true; 214661007b31SStefan Hajnoczi acb->req.error = -EINPROGRESS; 214761007b31SStefan Hajnoczi acb->req.sector = sector_num; 214861007b31SStefan Hajnoczi acb->req.nb_sectors = nb_sectors; 214961007b31SStefan Hajnoczi acb->req.qiov = qiov; 215061007b31SStefan Hajnoczi acb->req.flags = flags; 215161007b31SStefan Hajnoczi acb->is_write = is_write; 215261007b31SStefan Hajnoczi 215361007b31SStefan Hajnoczi co = qemu_coroutine_create(bdrv_co_do_rw); 215461007b31SStefan Hajnoczi qemu_coroutine_enter(co, acb); 215561007b31SStefan Hajnoczi 215661007b31SStefan Hajnoczi bdrv_co_maybe_schedule_bh(acb); 215761007b31SStefan Hajnoczi return &acb->common; 215861007b31SStefan Hajnoczi } 215961007b31SStefan Hajnoczi 216061007b31SStefan Hajnoczi static void coroutine_fn bdrv_aio_flush_co_entry(void *opaque) 216161007b31SStefan Hajnoczi { 216261007b31SStefan Hajnoczi BlockAIOCBCoroutine *acb = opaque; 216361007b31SStefan Hajnoczi BlockDriverState *bs = acb->common.bs; 216461007b31SStefan Hajnoczi 216561007b31SStefan Hajnoczi acb->req.error = bdrv_co_flush(bs); 216661007b31SStefan Hajnoczi bdrv_co_complete(acb); 216761007b31SStefan Hajnoczi } 216861007b31SStefan Hajnoczi 216961007b31SStefan Hajnoczi BlockAIOCB *bdrv_aio_flush(BlockDriverState *bs, 217061007b31SStefan Hajnoczi BlockCompletionFunc *cb, void *opaque) 217161007b31SStefan Hajnoczi { 217261007b31SStefan Hajnoczi trace_bdrv_aio_flush(bs, opaque); 217361007b31SStefan Hajnoczi 217461007b31SStefan Hajnoczi Coroutine *co; 217561007b31SStefan Hajnoczi BlockAIOCBCoroutine *acb; 217661007b31SStefan Hajnoczi 217761007b31SStefan Hajnoczi acb = qemu_aio_get(&bdrv_em_co_aiocb_info, bs, cb, opaque); 217861007b31SStefan Hajnoczi acb->need_bh = true; 217961007b31SStefan Hajnoczi acb->req.error = -EINPROGRESS; 218061007b31SStefan Hajnoczi 218161007b31SStefan Hajnoczi co = qemu_coroutine_create(bdrv_aio_flush_co_entry); 218261007b31SStefan Hajnoczi qemu_coroutine_enter(co, acb); 218361007b31SStefan Hajnoczi 218461007b31SStefan Hajnoczi bdrv_co_maybe_schedule_bh(acb); 218561007b31SStefan Hajnoczi return &acb->common; 218661007b31SStefan Hajnoczi } 218761007b31SStefan Hajnoczi 218861007b31SStefan Hajnoczi static void coroutine_fn bdrv_aio_discard_co_entry(void *opaque) 218961007b31SStefan Hajnoczi { 219061007b31SStefan Hajnoczi BlockAIOCBCoroutine *acb = opaque; 219161007b31SStefan Hajnoczi BlockDriverState *bs = acb->common.bs; 219261007b31SStefan Hajnoczi 219361007b31SStefan Hajnoczi acb->req.error = bdrv_co_discard(bs, acb->req.sector, acb->req.nb_sectors); 219461007b31SStefan Hajnoczi bdrv_co_complete(acb); 219561007b31SStefan Hajnoczi } 219661007b31SStefan Hajnoczi 219761007b31SStefan Hajnoczi BlockAIOCB *bdrv_aio_discard(BlockDriverState *bs, 219861007b31SStefan Hajnoczi int64_t sector_num, int nb_sectors, 219961007b31SStefan Hajnoczi BlockCompletionFunc *cb, void *opaque) 220061007b31SStefan Hajnoczi { 220161007b31SStefan Hajnoczi Coroutine *co; 220261007b31SStefan Hajnoczi BlockAIOCBCoroutine *acb; 220361007b31SStefan Hajnoczi 220461007b31SStefan Hajnoczi trace_bdrv_aio_discard(bs, sector_num, nb_sectors, opaque); 220561007b31SStefan Hajnoczi 220661007b31SStefan Hajnoczi acb = qemu_aio_get(&bdrv_em_co_aiocb_info, bs, cb, opaque); 220761007b31SStefan Hajnoczi acb->need_bh = true; 220861007b31SStefan Hajnoczi acb->req.error = -EINPROGRESS; 220961007b31SStefan Hajnoczi acb->req.sector = sector_num; 221061007b31SStefan Hajnoczi acb->req.nb_sectors = nb_sectors; 221161007b31SStefan Hajnoczi co = qemu_coroutine_create(bdrv_aio_discard_co_entry); 221261007b31SStefan Hajnoczi qemu_coroutine_enter(co, acb); 221361007b31SStefan Hajnoczi 221461007b31SStefan Hajnoczi bdrv_co_maybe_schedule_bh(acb); 221561007b31SStefan Hajnoczi return &acb->common; 221661007b31SStefan Hajnoczi } 221761007b31SStefan Hajnoczi 221861007b31SStefan Hajnoczi void *qemu_aio_get(const AIOCBInfo *aiocb_info, BlockDriverState *bs, 221961007b31SStefan Hajnoczi BlockCompletionFunc *cb, void *opaque) 222061007b31SStefan Hajnoczi { 222161007b31SStefan Hajnoczi BlockAIOCB *acb; 222261007b31SStefan Hajnoczi 2223c84b3192SPaolo Bonzini acb = g_malloc(aiocb_info->aiocb_size); 222461007b31SStefan Hajnoczi acb->aiocb_info = aiocb_info; 222561007b31SStefan Hajnoczi acb->bs = bs; 222661007b31SStefan Hajnoczi acb->cb = cb; 222761007b31SStefan Hajnoczi acb->opaque = opaque; 222861007b31SStefan Hajnoczi acb->refcnt = 1; 222961007b31SStefan Hajnoczi return acb; 223061007b31SStefan Hajnoczi } 223161007b31SStefan Hajnoczi 223261007b31SStefan Hajnoczi void qemu_aio_ref(void *p) 223361007b31SStefan Hajnoczi { 223461007b31SStefan Hajnoczi BlockAIOCB *acb = p; 223561007b31SStefan Hajnoczi acb->refcnt++; 223661007b31SStefan Hajnoczi } 223761007b31SStefan Hajnoczi 223861007b31SStefan Hajnoczi void qemu_aio_unref(void *p) 223961007b31SStefan Hajnoczi { 224061007b31SStefan Hajnoczi BlockAIOCB *acb = p; 224161007b31SStefan Hajnoczi assert(acb->refcnt > 0); 224261007b31SStefan Hajnoczi if (--acb->refcnt == 0) { 2243c84b3192SPaolo Bonzini g_free(acb); 224461007b31SStefan Hajnoczi } 224561007b31SStefan Hajnoczi } 224661007b31SStefan Hajnoczi 224761007b31SStefan Hajnoczi /**************************************************************/ 224861007b31SStefan Hajnoczi /* Coroutine block device emulation */ 224961007b31SStefan Hajnoczi 225061007b31SStefan Hajnoczi typedef struct CoroutineIOCompletion { 225161007b31SStefan Hajnoczi Coroutine *coroutine; 225261007b31SStefan Hajnoczi int ret; 225361007b31SStefan Hajnoczi } CoroutineIOCompletion; 225461007b31SStefan Hajnoczi 225561007b31SStefan Hajnoczi static void bdrv_co_io_em_complete(void *opaque, int ret) 225661007b31SStefan Hajnoczi { 225761007b31SStefan Hajnoczi CoroutineIOCompletion *co = opaque; 225861007b31SStefan Hajnoczi 225961007b31SStefan Hajnoczi co->ret = ret; 226061007b31SStefan Hajnoczi qemu_coroutine_enter(co->coroutine, NULL); 226161007b31SStefan Hajnoczi } 226261007b31SStefan Hajnoczi 226361007b31SStefan Hajnoczi static int coroutine_fn bdrv_co_io_em(BlockDriverState *bs, int64_t sector_num, 226461007b31SStefan Hajnoczi int nb_sectors, QEMUIOVector *iov, 226561007b31SStefan Hajnoczi bool is_write) 226661007b31SStefan Hajnoczi { 226761007b31SStefan Hajnoczi CoroutineIOCompletion co = { 226861007b31SStefan Hajnoczi .coroutine = qemu_coroutine_self(), 226961007b31SStefan Hajnoczi }; 227061007b31SStefan Hajnoczi BlockAIOCB *acb; 227161007b31SStefan Hajnoczi 227261007b31SStefan Hajnoczi if (is_write) { 227361007b31SStefan Hajnoczi acb = bs->drv->bdrv_aio_writev(bs, sector_num, iov, nb_sectors, 227461007b31SStefan Hajnoczi bdrv_co_io_em_complete, &co); 227561007b31SStefan Hajnoczi } else { 227661007b31SStefan Hajnoczi acb = bs->drv->bdrv_aio_readv(bs, sector_num, iov, nb_sectors, 227761007b31SStefan Hajnoczi bdrv_co_io_em_complete, &co); 227861007b31SStefan Hajnoczi } 227961007b31SStefan Hajnoczi 228061007b31SStefan Hajnoczi trace_bdrv_co_io_em(bs, sector_num, nb_sectors, is_write, acb); 228161007b31SStefan Hajnoczi if (!acb) { 228261007b31SStefan Hajnoczi return -EIO; 228361007b31SStefan Hajnoczi } 228461007b31SStefan Hajnoczi qemu_coroutine_yield(); 228561007b31SStefan Hajnoczi 228661007b31SStefan Hajnoczi return co.ret; 228761007b31SStefan Hajnoczi } 228861007b31SStefan Hajnoczi 228961007b31SStefan Hajnoczi static int coroutine_fn bdrv_co_readv_em(BlockDriverState *bs, 229061007b31SStefan Hajnoczi int64_t sector_num, int nb_sectors, 229161007b31SStefan Hajnoczi QEMUIOVector *iov) 229261007b31SStefan Hajnoczi { 229361007b31SStefan Hajnoczi return bdrv_co_io_em(bs, sector_num, nb_sectors, iov, false); 229461007b31SStefan Hajnoczi } 229561007b31SStefan Hajnoczi 229661007b31SStefan Hajnoczi static int coroutine_fn bdrv_co_writev_em(BlockDriverState *bs, 229761007b31SStefan Hajnoczi int64_t sector_num, int nb_sectors, 229861007b31SStefan Hajnoczi QEMUIOVector *iov) 229961007b31SStefan Hajnoczi { 230061007b31SStefan Hajnoczi return bdrv_co_io_em(bs, sector_num, nb_sectors, iov, true); 230161007b31SStefan Hajnoczi } 230261007b31SStefan Hajnoczi 230361007b31SStefan Hajnoczi static void coroutine_fn bdrv_flush_co_entry(void *opaque) 230461007b31SStefan Hajnoczi { 230561007b31SStefan Hajnoczi RwCo *rwco = opaque; 230661007b31SStefan Hajnoczi 230761007b31SStefan Hajnoczi rwco->ret = bdrv_co_flush(rwco->bs); 230861007b31SStefan Hajnoczi } 230961007b31SStefan Hajnoczi 231061007b31SStefan Hajnoczi int coroutine_fn bdrv_co_flush(BlockDriverState *bs) 231161007b31SStefan Hajnoczi { 231261007b31SStefan Hajnoczi int ret; 231361007b31SStefan Hajnoczi 23141b6bc94dSDimitris Aragiorgis if (!bs || !bdrv_is_inserted(bs) || bdrv_is_read_only(bs) || 23151b6bc94dSDimitris Aragiorgis bdrv_is_sg(bs)) { 231661007b31SStefan Hajnoczi return 0; 231761007b31SStefan Hajnoczi } 231861007b31SStefan Hajnoczi 231961007b31SStefan Hajnoczi /* Write back cached data to the OS even with cache=unsafe */ 232061007b31SStefan Hajnoczi BLKDBG_EVENT(bs->file, BLKDBG_FLUSH_TO_OS); 232161007b31SStefan Hajnoczi if (bs->drv->bdrv_co_flush_to_os) { 232261007b31SStefan Hajnoczi ret = bs->drv->bdrv_co_flush_to_os(bs); 232361007b31SStefan Hajnoczi if (ret < 0) { 232461007b31SStefan Hajnoczi return ret; 232561007b31SStefan Hajnoczi } 232661007b31SStefan Hajnoczi } 232761007b31SStefan Hajnoczi 232861007b31SStefan Hajnoczi /* But don't actually force it to the disk with cache=unsafe */ 232961007b31SStefan Hajnoczi if (bs->open_flags & BDRV_O_NO_FLUSH) { 233061007b31SStefan Hajnoczi goto flush_parent; 233161007b31SStefan Hajnoczi } 233261007b31SStefan Hajnoczi 233361007b31SStefan Hajnoczi BLKDBG_EVENT(bs->file, BLKDBG_FLUSH_TO_DISK); 233461007b31SStefan Hajnoczi if (bs->drv->bdrv_co_flush_to_disk) { 233561007b31SStefan Hajnoczi ret = bs->drv->bdrv_co_flush_to_disk(bs); 233661007b31SStefan Hajnoczi } else if (bs->drv->bdrv_aio_flush) { 233761007b31SStefan Hajnoczi BlockAIOCB *acb; 233861007b31SStefan Hajnoczi CoroutineIOCompletion co = { 233961007b31SStefan Hajnoczi .coroutine = qemu_coroutine_self(), 234061007b31SStefan Hajnoczi }; 234161007b31SStefan Hajnoczi 234261007b31SStefan Hajnoczi acb = bs->drv->bdrv_aio_flush(bs, bdrv_co_io_em_complete, &co); 234361007b31SStefan Hajnoczi if (acb == NULL) { 234461007b31SStefan Hajnoczi ret = -EIO; 234561007b31SStefan Hajnoczi } else { 234661007b31SStefan Hajnoczi qemu_coroutine_yield(); 234761007b31SStefan Hajnoczi ret = co.ret; 234861007b31SStefan Hajnoczi } 234961007b31SStefan Hajnoczi } else { 235061007b31SStefan Hajnoczi /* 235161007b31SStefan Hajnoczi * Some block drivers always operate in either writethrough or unsafe 235261007b31SStefan Hajnoczi * mode and don't support bdrv_flush therefore. Usually qemu doesn't 235361007b31SStefan Hajnoczi * know how the server works (because the behaviour is hardcoded or 235461007b31SStefan Hajnoczi * depends on server-side configuration), so we can't ensure that 235561007b31SStefan Hajnoczi * everything is safe on disk. Returning an error doesn't work because 235661007b31SStefan Hajnoczi * that would break guests even if the server operates in writethrough 235761007b31SStefan Hajnoczi * mode. 235861007b31SStefan Hajnoczi * 235961007b31SStefan Hajnoczi * Let's hope the user knows what he's doing. 236061007b31SStefan Hajnoczi */ 236161007b31SStefan Hajnoczi ret = 0; 236261007b31SStefan Hajnoczi } 236361007b31SStefan Hajnoczi if (ret < 0) { 236461007b31SStefan Hajnoczi return ret; 236561007b31SStefan Hajnoczi } 236661007b31SStefan Hajnoczi 236761007b31SStefan Hajnoczi /* Now flush the underlying protocol. It will also have BDRV_O_NO_FLUSH 236861007b31SStefan Hajnoczi * in the case of cache=unsafe, so there are no useless flushes. 236961007b31SStefan Hajnoczi */ 237061007b31SStefan Hajnoczi flush_parent: 23719a4f4c31SKevin Wolf return bs->file ? bdrv_co_flush(bs->file->bs) : 0; 237261007b31SStefan Hajnoczi } 237361007b31SStefan Hajnoczi 237461007b31SStefan Hajnoczi int bdrv_flush(BlockDriverState *bs) 237561007b31SStefan Hajnoczi { 237661007b31SStefan Hajnoczi Coroutine *co; 237761007b31SStefan Hajnoczi RwCo rwco = { 237861007b31SStefan Hajnoczi .bs = bs, 237961007b31SStefan Hajnoczi .ret = NOT_DONE, 238061007b31SStefan Hajnoczi }; 238161007b31SStefan Hajnoczi 238261007b31SStefan Hajnoczi if (qemu_in_coroutine()) { 238361007b31SStefan Hajnoczi /* Fast-path if already in coroutine context */ 238461007b31SStefan Hajnoczi bdrv_flush_co_entry(&rwco); 238561007b31SStefan Hajnoczi } else { 238661007b31SStefan Hajnoczi AioContext *aio_context = bdrv_get_aio_context(bs); 238761007b31SStefan Hajnoczi 238861007b31SStefan Hajnoczi co = qemu_coroutine_create(bdrv_flush_co_entry); 238961007b31SStefan Hajnoczi qemu_coroutine_enter(co, &rwco); 239061007b31SStefan Hajnoczi while (rwco.ret == NOT_DONE) { 239161007b31SStefan Hajnoczi aio_poll(aio_context, true); 239261007b31SStefan Hajnoczi } 239361007b31SStefan Hajnoczi } 239461007b31SStefan Hajnoczi 239561007b31SStefan Hajnoczi return rwco.ret; 239661007b31SStefan Hajnoczi } 239761007b31SStefan Hajnoczi 239861007b31SStefan Hajnoczi typedef struct DiscardCo { 239961007b31SStefan Hajnoczi BlockDriverState *bs; 240061007b31SStefan Hajnoczi int64_t sector_num; 240161007b31SStefan Hajnoczi int nb_sectors; 240261007b31SStefan Hajnoczi int ret; 240361007b31SStefan Hajnoczi } DiscardCo; 240461007b31SStefan Hajnoczi static void coroutine_fn bdrv_discard_co_entry(void *opaque) 240561007b31SStefan Hajnoczi { 240661007b31SStefan Hajnoczi DiscardCo *rwco = opaque; 240761007b31SStefan Hajnoczi 240861007b31SStefan Hajnoczi rwco->ret = bdrv_co_discard(rwco->bs, rwco->sector_num, rwco->nb_sectors); 240961007b31SStefan Hajnoczi } 241061007b31SStefan Hajnoczi 241161007b31SStefan Hajnoczi int coroutine_fn bdrv_co_discard(BlockDriverState *bs, int64_t sector_num, 241261007b31SStefan Hajnoczi int nb_sectors) 241361007b31SStefan Hajnoczi { 241461007b31SStefan Hajnoczi int max_discard, ret; 241561007b31SStefan Hajnoczi 241661007b31SStefan Hajnoczi if (!bs->drv) { 241761007b31SStefan Hajnoczi return -ENOMEDIUM; 241861007b31SStefan Hajnoczi } 241961007b31SStefan Hajnoczi 242061007b31SStefan Hajnoczi ret = bdrv_check_request(bs, sector_num, nb_sectors); 242161007b31SStefan Hajnoczi if (ret < 0) { 242261007b31SStefan Hajnoczi return ret; 242361007b31SStefan Hajnoczi } else if (bs->read_only) { 2424eaf5fe2dSPaolo Bonzini return -EPERM; 242561007b31SStefan Hajnoczi } 242661007b31SStefan Hajnoczi 242761007b31SStefan Hajnoczi /* Do nothing if disabled. */ 242861007b31SStefan Hajnoczi if (!(bs->open_flags & BDRV_O_UNMAP)) { 242961007b31SStefan Hajnoczi return 0; 243061007b31SStefan Hajnoczi } 243161007b31SStefan Hajnoczi 243261007b31SStefan Hajnoczi if (!bs->drv->bdrv_co_discard && !bs->drv->bdrv_aio_discard) { 243361007b31SStefan Hajnoczi return 0; 243461007b31SStefan Hajnoczi } 243561007b31SStefan Hajnoczi 243650824995SFam Zheng bdrv_set_dirty(bs, sector_num, nb_sectors); 243750824995SFam Zheng 243861007b31SStefan Hajnoczi max_discard = MIN_NON_ZERO(bs->bl.max_discard, BDRV_REQUEST_MAX_SECTORS); 243961007b31SStefan Hajnoczi while (nb_sectors > 0) { 244061007b31SStefan Hajnoczi int ret; 244161007b31SStefan Hajnoczi int num = nb_sectors; 244261007b31SStefan Hajnoczi 244361007b31SStefan Hajnoczi /* align request */ 244461007b31SStefan Hajnoczi if (bs->bl.discard_alignment && 244561007b31SStefan Hajnoczi num >= bs->bl.discard_alignment && 244661007b31SStefan Hajnoczi sector_num % bs->bl.discard_alignment) { 244761007b31SStefan Hajnoczi if (num > bs->bl.discard_alignment) { 244861007b31SStefan Hajnoczi num = bs->bl.discard_alignment; 244961007b31SStefan Hajnoczi } 245061007b31SStefan Hajnoczi num -= sector_num % bs->bl.discard_alignment; 245161007b31SStefan Hajnoczi } 245261007b31SStefan Hajnoczi 245361007b31SStefan Hajnoczi /* limit request size */ 245461007b31SStefan Hajnoczi if (num > max_discard) { 245561007b31SStefan Hajnoczi num = max_discard; 245661007b31SStefan Hajnoczi } 245761007b31SStefan Hajnoczi 245861007b31SStefan Hajnoczi if (bs->drv->bdrv_co_discard) { 245961007b31SStefan Hajnoczi ret = bs->drv->bdrv_co_discard(bs, sector_num, num); 246061007b31SStefan Hajnoczi } else { 246161007b31SStefan Hajnoczi BlockAIOCB *acb; 246261007b31SStefan Hajnoczi CoroutineIOCompletion co = { 246361007b31SStefan Hajnoczi .coroutine = qemu_coroutine_self(), 246461007b31SStefan Hajnoczi }; 246561007b31SStefan Hajnoczi 246661007b31SStefan Hajnoczi acb = bs->drv->bdrv_aio_discard(bs, sector_num, nb_sectors, 246761007b31SStefan Hajnoczi bdrv_co_io_em_complete, &co); 246861007b31SStefan Hajnoczi if (acb == NULL) { 246961007b31SStefan Hajnoczi return -EIO; 247061007b31SStefan Hajnoczi } else { 247161007b31SStefan Hajnoczi qemu_coroutine_yield(); 247261007b31SStefan Hajnoczi ret = co.ret; 247361007b31SStefan Hajnoczi } 247461007b31SStefan Hajnoczi } 247561007b31SStefan Hajnoczi if (ret && ret != -ENOTSUP) { 247661007b31SStefan Hajnoczi return ret; 247761007b31SStefan Hajnoczi } 247861007b31SStefan Hajnoczi 247961007b31SStefan Hajnoczi sector_num += num; 248061007b31SStefan Hajnoczi nb_sectors -= num; 248161007b31SStefan Hajnoczi } 248261007b31SStefan Hajnoczi return 0; 248361007b31SStefan Hajnoczi } 248461007b31SStefan Hajnoczi 248561007b31SStefan Hajnoczi int bdrv_discard(BlockDriverState *bs, int64_t sector_num, int nb_sectors) 248661007b31SStefan Hajnoczi { 248761007b31SStefan Hajnoczi Coroutine *co; 248861007b31SStefan Hajnoczi DiscardCo rwco = { 248961007b31SStefan Hajnoczi .bs = bs, 249061007b31SStefan Hajnoczi .sector_num = sector_num, 249161007b31SStefan Hajnoczi .nb_sectors = nb_sectors, 249261007b31SStefan Hajnoczi .ret = NOT_DONE, 249361007b31SStefan Hajnoczi }; 249461007b31SStefan Hajnoczi 249561007b31SStefan Hajnoczi if (qemu_in_coroutine()) { 249661007b31SStefan Hajnoczi /* Fast-path if already in coroutine context */ 249761007b31SStefan Hajnoczi bdrv_discard_co_entry(&rwco); 249861007b31SStefan Hajnoczi } else { 249961007b31SStefan Hajnoczi AioContext *aio_context = bdrv_get_aio_context(bs); 250061007b31SStefan Hajnoczi 250161007b31SStefan Hajnoczi co = qemu_coroutine_create(bdrv_discard_co_entry); 250261007b31SStefan Hajnoczi qemu_coroutine_enter(co, &rwco); 250361007b31SStefan Hajnoczi while (rwco.ret == NOT_DONE) { 250461007b31SStefan Hajnoczi aio_poll(aio_context, true); 250561007b31SStefan Hajnoczi } 250661007b31SStefan Hajnoczi } 250761007b31SStefan Hajnoczi 250861007b31SStefan Hajnoczi return rwco.ret; 250961007b31SStefan Hajnoczi } 251061007b31SStefan Hajnoczi 251161007b31SStefan Hajnoczi /* needed for generic scsi interface */ 251261007b31SStefan Hajnoczi 251361007b31SStefan Hajnoczi int bdrv_ioctl(BlockDriverState *bs, unsigned long int req, void *buf) 251461007b31SStefan Hajnoczi { 251561007b31SStefan Hajnoczi BlockDriver *drv = bs->drv; 251661007b31SStefan Hajnoczi 251761007b31SStefan Hajnoczi if (drv && drv->bdrv_ioctl) 251861007b31SStefan Hajnoczi return drv->bdrv_ioctl(bs, req, buf); 251961007b31SStefan Hajnoczi return -ENOTSUP; 252061007b31SStefan Hajnoczi } 252161007b31SStefan Hajnoczi 252261007b31SStefan Hajnoczi BlockAIOCB *bdrv_aio_ioctl(BlockDriverState *bs, 252361007b31SStefan Hajnoczi unsigned long int req, void *buf, 252461007b31SStefan Hajnoczi BlockCompletionFunc *cb, void *opaque) 252561007b31SStefan Hajnoczi { 252661007b31SStefan Hajnoczi BlockDriver *drv = bs->drv; 252761007b31SStefan Hajnoczi 252861007b31SStefan Hajnoczi if (drv && drv->bdrv_aio_ioctl) 252961007b31SStefan Hajnoczi return drv->bdrv_aio_ioctl(bs, req, buf, cb, opaque); 253061007b31SStefan Hajnoczi return NULL; 253161007b31SStefan Hajnoczi } 253261007b31SStefan Hajnoczi 253361007b31SStefan Hajnoczi void *qemu_blockalign(BlockDriverState *bs, size_t size) 253461007b31SStefan Hajnoczi { 253561007b31SStefan Hajnoczi return qemu_memalign(bdrv_opt_mem_align(bs), size); 253661007b31SStefan Hajnoczi } 253761007b31SStefan Hajnoczi 253861007b31SStefan Hajnoczi void *qemu_blockalign0(BlockDriverState *bs, size_t size) 253961007b31SStefan Hajnoczi { 254061007b31SStefan Hajnoczi return memset(qemu_blockalign(bs, size), 0, size); 254161007b31SStefan Hajnoczi } 254261007b31SStefan Hajnoczi 254361007b31SStefan Hajnoczi void *qemu_try_blockalign(BlockDriverState *bs, size_t size) 254461007b31SStefan Hajnoczi { 254561007b31SStefan Hajnoczi size_t align = bdrv_opt_mem_align(bs); 254661007b31SStefan Hajnoczi 254761007b31SStefan Hajnoczi /* Ensure that NULL is never returned on success */ 254861007b31SStefan Hajnoczi assert(align > 0); 254961007b31SStefan Hajnoczi if (size == 0) { 255061007b31SStefan Hajnoczi size = align; 255161007b31SStefan Hajnoczi } 255261007b31SStefan Hajnoczi 255361007b31SStefan Hajnoczi return qemu_try_memalign(align, size); 255461007b31SStefan Hajnoczi } 255561007b31SStefan Hajnoczi 255661007b31SStefan Hajnoczi void *qemu_try_blockalign0(BlockDriverState *bs, size_t size) 255761007b31SStefan Hajnoczi { 255861007b31SStefan Hajnoczi void *mem = qemu_try_blockalign(bs, size); 255961007b31SStefan Hajnoczi 256061007b31SStefan Hajnoczi if (mem) { 256161007b31SStefan Hajnoczi memset(mem, 0, size); 256261007b31SStefan Hajnoczi } 256361007b31SStefan Hajnoczi 256461007b31SStefan Hajnoczi return mem; 256561007b31SStefan Hajnoczi } 256661007b31SStefan Hajnoczi 256761007b31SStefan Hajnoczi /* 256861007b31SStefan Hajnoczi * Check if all memory in this vector is sector aligned. 256961007b31SStefan Hajnoczi */ 257061007b31SStefan Hajnoczi bool bdrv_qiov_is_aligned(BlockDriverState *bs, QEMUIOVector *qiov) 257161007b31SStefan Hajnoczi { 257261007b31SStefan Hajnoczi int i; 25734196d2f0SDenis V. Lunev size_t alignment = bdrv_min_mem_align(bs); 257461007b31SStefan Hajnoczi 257561007b31SStefan Hajnoczi for (i = 0; i < qiov->niov; i++) { 257661007b31SStefan Hajnoczi if ((uintptr_t) qiov->iov[i].iov_base % alignment) { 257761007b31SStefan Hajnoczi return false; 257861007b31SStefan Hajnoczi } 257961007b31SStefan Hajnoczi if (qiov->iov[i].iov_len % alignment) { 258061007b31SStefan Hajnoczi return false; 258161007b31SStefan Hajnoczi } 258261007b31SStefan Hajnoczi } 258361007b31SStefan Hajnoczi 258461007b31SStefan Hajnoczi return true; 258561007b31SStefan Hajnoczi } 258661007b31SStefan Hajnoczi 258761007b31SStefan Hajnoczi void bdrv_add_before_write_notifier(BlockDriverState *bs, 258861007b31SStefan Hajnoczi NotifierWithReturn *notifier) 258961007b31SStefan Hajnoczi { 259061007b31SStefan Hajnoczi notifier_with_return_list_add(&bs->before_write_notifiers, notifier); 259161007b31SStefan Hajnoczi } 259261007b31SStefan Hajnoczi 259361007b31SStefan Hajnoczi void bdrv_io_plug(BlockDriverState *bs) 259461007b31SStefan Hajnoczi { 259561007b31SStefan Hajnoczi BlockDriver *drv = bs->drv; 259661007b31SStefan Hajnoczi if (drv && drv->bdrv_io_plug) { 259761007b31SStefan Hajnoczi drv->bdrv_io_plug(bs); 259861007b31SStefan Hajnoczi } else if (bs->file) { 25999a4f4c31SKevin Wolf bdrv_io_plug(bs->file->bs); 260061007b31SStefan Hajnoczi } 260161007b31SStefan Hajnoczi } 260261007b31SStefan Hajnoczi 260361007b31SStefan Hajnoczi void bdrv_io_unplug(BlockDriverState *bs) 260461007b31SStefan Hajnoczi { 260561007b31SStefan Hajnoczi BlockDriver *drv = bs->drv; 260661007b31SStefan Hajnoczi if (drv && drv->bdrv_io_unplug) { 260761007b31SStefan Hajnoczi drv->bdrv_io_unplug(bs); 260861007b31SStefan Hajnoczi } else if (bs->file) { 26099a4f4c31SKevin Wolf bdrv_io_unplug(bs->file->bs); 261061007b31SStefan Hajnoczi } 261161007b31SStefan Hajnoczi } 261261007b31SStefan Hajnoczi 261361007b31SStefan Hajnoczi void bdrv_flush_io_queue(BlockDriverState *bs) 261461007b31SStefan Hajnoczi { 261561007b31SStefan Hajnoczi BlockDriver *drv = bs->drv; 261661007b31SStefan Hajnoczi if (drv && drv->bdrv_flush_io_queue) { 261761007b31SStefan Hajnoczi drv->bdrv_flush_io_queue(bs); 261861007b31SStefan Hajnoczi } else if (bs->file) { 26199a4f4c31SKevin Wolf bdrv_flush_io_queue(bs->file->bs); 262061007b31SStefan Hajnoczi } 2621f406c03cSAlexander Yarygin bdrv_start_throttled_reqs(bs); 262261007b31SStefan Hajnoczi } 2623