From patchwork Tue Sep 10 10:23:24 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Vladimir Sementsov-Ogievskiy X-Patchwork-Id: 1160203 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=virtuozzo.com Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 46SLlm3Kcpz9sNf for ; Tue, 10 Sep 2019 20:25:56 +1000 (AEST) Received: from localhost ([::1]:37542 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1i7dLO-0000qr-97 for incoming@patchwork.ozlabs.org; Tue, 10 Sep 2019 06:25:54 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:56674) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1i7dJT-0000Xo-4d for qemu-devel@nongnu.org; Tue, 10 Sep 2019 06:23:58 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1i7dJL-0001wu-6Z for qemu-devel@nongnu.org; Tue, 10 Sep 2019 06:23:54 -0400 Received: from relay.sw.ru ([185.231.240.75]:60034) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1i7dJB-0001oE-Ep; Tue, 10 Sep 2019 06:23:38 -0400 Received: from [10.94.3.0] (helo=kvm.qa.sw.ru) by relay.sw.ru with esmtp (Exim 4.92) (envelope-from ) id 1i7dJ7-0007it-Ee; Tue, 10 Sep 2019 13:23:33 +0300 From: Vladimir Sementsov-Ogievskiy To: qemu-block@nongnu.org Date: Tue, 10 Sep 2019 13:23:24 +0300 Message-Id: <20190910102332.20560-7-vsementsov@virtuozzo.com> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20190910102332.20560-1-vsementsov@virtuozzo.com> References: <20190910102332.20560-1-vsementsov@virtuozzo.com> MIME-Version: 1.0 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x X-Received-From: 185.231.240.75 Subject: [Qemu-devel] [PATCH v11 06/14] block: move block_copy from block/backup.c to separate file X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: fam@euphon.net, kwolf@redhat.com, vsementsov@virtuozzo.com, wencongyang2@huawei.com, xiechanglong.d@gmail.com, qemu-devel@nongnu.org, armbru@redhat.com, jsnow@redhat.com, stefanha@redhat.com, den@openvz.org, mreitz@redhat.com Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" Split block_copy to separate file, to be cleanly shared with backup-top filter driver in further commits. It's a clean movement, the only change is drop "static" from interface functions. Signed-off-by: Vladimir Sementsov-Ogievskiy Reviewed-by: Max Reitz --- include/block/block-copy.h | 76 ++++++++ block/backup.c | 346 +------------------------------------ block/block-copy.c | 324 ++++++++++++++++++++++++++++++++++ block/Makefile.objs | 1 + block/trace-events | 2 + 5 files changed, 404 insertions(+), 345 deletions(-) create mode 100644 include/block/block-copy.h create mode 100644 block/block-copy.c diff --git a/include/block/block-copy.h b/include/block/block-copy.h new file mode 100644 index 0000000000..54f90d0c9a --- /dev/null +++ b/include/block/block-copy.h @@ -0,0 +1,76 @@ +/* + * block_copy API + * + * Copyright (C) 2013 Proxmox Server Solutions + * Copyright (c) 2019 Virtuozzo International GmbH. + * + * Authors: + * Dietmar Maurer (dietmar@proxmox.com) + * Vladimir Sementsov-Ogievskiy + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + */ + +#ifndef BLOCK_COPY_H +#define BLOCK_COPY_H + +#include "block/block.h" + +typedef void (*ProgressBytesCallbackFunc)(int64_t bytes, void *opaque); +typedef void (*ProgressResetCallbackFunc)(void *opaque); +typedef struct BlockCopyState { + BlockBackend *source; + BlockBackend *target; + BdrvDirtyBitmap *copy_bitmap; + int64_t cluster_size; + bool use_copy_range; + int64_t copy_range_size; + uint64_t len; + + BdrvRequestFlags write_flags; + + /* + * skip_unallocated: + * + * Used by sync=top jobs, which first scan the source node for unallocated + * areas and clear them in the copy_bitmap. During this process, the bitmap + * is thus not fully initialized: It may still have bits set for areas that + * are unallocated and should actually not be copied. + * + * This is indicated by skip_unallocated. + * + * In this case, block_copy() will query the source’s allocation status, + * skip unallocated regions, clear them in the copy_bitmap, and invoke + * block_copy_reset_unallocated() every time it does. + */ + bool skip_unallocated; + + /* progress_bytes_callback: called when some copying progress is done. */ + ProgressBytesCallbackFunc progress_bytes_callback; + + /* + * progress_reset_callback: called when some bytes reset from copy_bitmap + * (see @skip_unallocated above). The callee is assumed to recalculate how + * many bytes remain based on the dirty bit count of copy_bitmap. + */ + ProgressResetCallbackFunc progress_reset_callback; + void *progress_opaque; +} BlockCopyState; + +BlockCopyState *block_copy_state_new( + BlockDriverState *source, BlockDriverState *target, + int64_t cluster_size, BdrvRequestFlags write_flags, + ProgressBytesCallbackFunc progress_bytes_callback, + ProgressResetCallbackFunc progress_reset_callback, + void *progress_opaque, Error **errp); + +void block_copy_state_free(BlockCopyState *s); + +int64_t block_copy_reset_unallocated(BlockCopyState *s, + int64_t offset, int64_t *count); + +int coroutine_fn block_copy(BlockCopyState *s, int64_t start, uint64_t bytes, + bool *error_is_read, bool is_write_notifier); + +#endif /* BLOCK_COPY_H */ diff --git a/block/backup.c b/block/backup.c index 7a99ff14aa..4613b8c88d 100644 --- a/block/backup.c +++ b/block/backup.c @@ -18,6 +18,7 @@ #include "block/block_int.h" #include "block/blockjob_int.h" #include "block/block_backup.h" +#include "block/block-copy.h" #include "qapi/error.h" #include "qapi/qmp/qerror.h" #include "qemu/ratelimit.h" @@ -35,47 +36,6 @@ typedef struct CowRequest { CoQueue wait_queue; /* coroutines blocked on this request */ } CowRequest; -typedef void (*ProgressBytesCallbackFunc)(int64_t bytes, void *opaque); -typedef void (*ProgressResetCallbackFunc)(void *opaque); -typedef struct BlockCopyState { - BlockBackend *source; - BlockBackend *target; - BdrvDirtyBitmap *copy_bitmap; - int64_t cluster_size; - bool use_copy_range; - int64_t copy_range_size; - uint64_t len; - - BdrvRequestFlags write_flags; - - /* - * skip_unallocated: - * - * Used by sync=top jobs, which first scan the source node for unallocated - * areas and clear them in the copy_bitmap. During this process, the bitmap - * is thus not fully initialized: It may still have bits set for areas that - * are unallocated and should actually not be copied. - * - * This is indicated by skip_unallocated. - * - * In this case, block_copy() will query the source’s allocation status, - * skip unallocated regions, clear them in the copy_bitmap, and invoke - * block_copy_reset_unallocated() every time it does. - */ - bool skip_unallocated; - - /* progress_bytes_callback: called when some copying progress is done. */ - ProgressBytesCallbackFunc progress_bytes_callback; - - /* - * progress_reset_callback: called when some bytes reset from copy_bitmap - * (see @skip_unallocated above). The callee is assumed to recalculate how - * many bytes remain based on the dirty bit count of copy_bitmap. - */ - ProgressResetCallbackFunc progress_reset_callback; - void *progress_opaque; -} BlockCopyState; - typedef struct BackupBlockJob { BlockJob common; BlockDriverState *source_bs; @@ -135,310 +95,6 @@ static void cow_request_end(CowRequest *req) qemu_co_queue_restart_all(&req->wait_queue); } -static void block_copy_state_free(BlockCopyState *s) -{ - if (!s) { - return; - } - - bdrv_release_dirty_bitmap(blk_bs(s->source), s->copy_bitmap); - blk_unref(s->source); - blk_unref(s->target); - g_free(s); -} - -static BlockCopyState *block_copy_state_new( - BlockDriverState *source, BlockDriverState *target, - int64_t cluster_size, BdrvRequestFlags write_flags, - ProgressBytesCallbackFunc progress_bytes_callback, - ProgressResetCallbackFunc progress_reset_callback, - void *progress_opaque, Error **errp) -{ - BlockCopyState *s; - int ret; - uint64_t no_resize = BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE | - BLK_PERM_WRITE_UNCHANGED | BLK_PERM_GRAPH_MOD; - BdrvDirtyBitmap *copy_bitmap; - - copy_bitmap = bdrv_create_dirty_bitmap(source, cluster_size, NULL, errp); - if (!copy_bitmap) { - return NULL; - } - bdrv_disable_dirty_bitmap(copy_bitmap); - - s = g_new(BlockCopyState, 1); - *s = (BlockCopyState) { - .source = blk_new(bdrv_get_aio_context(source), - BLK_PERM_CONSISTENT_READ, no_resize), - .target = blk_new(bdrv_get_aio_context(target), - BLK_PERM_WRITE, no_resize), - .copy_bitmap = copy_bitmap, - .cluster_size = cluster_size, - .len = bdrv_dirty_bitmap_size(copy_bitmap), - .write_flags = write_flags, - .use_copy_range = !(write_flags & BDRV_REQ_WRITE_COMPRESSED), - .progress_bytes_callback = progress_bytes_callback, - .progress_reset_callback = progress_reset_callback, - .progress_opaque = progress_opaque, - }; - - s->copy_range_size = QEMU_ALIGN_UP(MIN(blk_get_max_transfer(s->source), - blk_get_max_transfer(s->target)), - s->cluster_size); - - /* - * We just allow aio context change on our block backends. block_copy() user - * (now it's only backup) is responsible for source and target being in same - * aio context. - */ - blk_set_disable_request_queuing(s->source, true); - blk_set_allow_aio_context_change(s->source, true); - blk_set_disable_request_queuing(s->target, true); - blk_set_allow_aio_context_change(s->target, true); - - ret = blk_insert_bs(s->source, source, errp); - if (ret < 0) { - goto fail; - } - - ret = blk_insert_bs(s->target, target, errp); - if (ret < 0) { - goto fail; - } - - return s; - -fail: - block_copy_state_free(s); - - return NULL; -} - -/* - * Copy range to target with a bounce buffer and return the bytes copied. If - * error occurred, return a negative error number - */ -static int coroutine_fn block_copy_with_bounce_buffer(BlockCopyState *s, - int64_t start, - int64_t end, - bool is_write_notifier, - bool *error_is_read, - void **bounce_buffer) -{ - int ret; - int nbytes; - int read_flags = is_write_notifier ? BDRV_REQ_NO_SERIALISING : 0; - - assert(QEMU_IS_ALIGNED(start, s->cluster_size)); - bdrv_reset_dirty_bitmap(s->copy_bitmap, start, s->cluster_size); - nbytes = MIN(s->cluster_size, s->len - start); - if (!*bounce_buffer) { - *bounce_buffer = blk_blockalign(s->source, s->cluster_size); - } - - ret = blk_co_pread(s->source, start, nbytes, *bounce_buffer, read_flags); - if (ret < 0) { - trace_block_copy_with_bounce_buffer_read_fail(s, start, ret); - if (error_is_read) { - *error_is_read = true; - } - goto fail; - } - - ret = blk_co_pwrite(s->target, start, nbytes, *bounce_buffer, - s->write_flags); - if (ret < 0) { - trace_block_copy_with_bounce_buffer_write_fail(s, start, ret); - if (error_is_read) { - *error_is_read = false; - } - goto fail; - } - - return nbytes; -fail: - bdrv_set_dirty_bitmap(s->copy_bitmap, start, s->cluster_size); - return ret; - -} - -/* - * Copy range to target and return the bytes copied. If error occurred, return a - * negative error number. - */ -static int coroutine_fn block_copy_with_offload(BlockCopyState *s, - int64_t start, - int64_t end, - bool is_write_notifier) -{ - int ret; - int nr_clusters; - int nbytes; - int read_flags = is_write_notifier ? BDRV_REQ_NO_SERIALISING : 0; - - assert(QEMU_IS_ALIGNED(s->copy_range_size, s->cluster_size)); - assert(QEMU_IS_ALIGNED(start, s->cluster_size)); - nbytes = MIN(s->copy_range_size, MIN(end, s->len) - start); - nr_clusters = DIV_ROUND_UP(nbytes, s->cluster_size); - bdrv_reset_dirty_bitmap(s->copy_bitmap, start, - s->cluster_size * nr_clusters); - ret = blk_co_copy_range(s->source, start, s->target, start, nbytes, - read_flags, s->write_flags); - if (ret < 0) { - trace_block_copy_with_offload_fail(s, start, ret); - bdrv_set_dirty_bitmap(s->copy_bitmap, start, - s->cluster_size * nr_clusters); - return ret; - } - - return nbytes; -} - -/* - * Check if the cluster starting at offset is allocated or not. - * return via pnum the number of contiguous clusters sharing this allocation. - */ -static int block_copy_is_cluster_allocated(BlockCopyState *s, int64_t offset, - int64_t *pnum) -{ - BlockDriverState *bs = blk_bs(s->source); - int64_t count, total_count = 0; - int64_t bytes = s->len - offset; - int ret; - - assert(QEMU_IS_ALIGNED(offset, s->cluster_size)); - - while (true) { - ret = bdrv_is_allocated(bs, offset, bytes, &count); - if (ret < 0) { - return ret; - } - - total_count += count; - - if (ret || count == 0) { - /* - * ret: partial segment(s) are considered allocated. - * otherwise: unallocated tail is treated as an entire segment. - */ - *pnum = DIV_ROUND_UP(total_count, s->cluster_size); - return ret; - } - - /* Unallocated segment(s) with uncertain following segment(s) */ - if (total_count >= s->cluster_size) { - *pnum = total_count / s->cluster_size; - return 0; - } - - offset += count; - bytes -= count; - } -} - -/* - * Reset bits in copy_bitmap starting at offset if they represent unallocated - * data in the image. May reset subsequent contiguous bits. - * @return 0 when the cluster at @offset was unallocated, - * 1 otherwise, and -ret on error. - */ -static int64_t block_copy_reset_unallocated(BlockCopyState *s, - int64_t offset, int64_t *count) -{ - int ret; - int64_t clusters, bytes; - - ret = block_copy_is_cluster_allocated(s, offset, &clusters); - if (ret < 0) { - return ret; - } - - bytes = clusters * s->cluster_size; - - if (!ret) { - bdrv_reset_dirty_bitmap(s->copy_bitmap, offset, bytes); - s->progress_reset_callback(s->progress_opaque); - } - - *count = bytes; - return ret; -} - -static int coroutine_fn block_copy(BlockCopyState *s, - int64_t start, uint64_t bytes, - bool *error_is_read, - bool is_write_notifier) -{ - int ret = 0; - int64_t end = bytes + start; /* bytes */ - void *bounce_buffer = NULL; - int64_t status_bytes; - - /* - * block_copy() user is responsible for keeping source and target in same - * aio context - */ - assert(blk_get_aio_context(s->source) == blk_get_aio_context(s->target)); - - assert(QEMU_IS_ALIGNED(start, s->cluster_size)); - assert(QEMU_IS_ALIGNED(end, s->cluster_size)); - - while (start < end) { - int64_t dirty_end; - - if (!bdrv_dirty_bitmap_get(s->copy_bitmap, start)) { - trace_block_copy_skip(s, start); - start += s->cluster_size; - continue; /* already copied */ - } - - dirty_end = bdrv_dirty_bitmap_next_zero(s->copy_bitmap, start, - (end - start)); - if (dirty_end < 0) { - dirty_end = end; - } - - if (s->skip_unallocated) { - ret = block_copy_reset_unallocated(s, start, &status_bytes); - if (ret == 0) { - trace_block_copy_skip_range(s, start, status_bytes); - start += status_bytes; - continue; - } - /* Clamp to known allocated region */ - dirty_end = MIN(dirty_end, start + status_bytes); - } - - trace_block_copy_process(s, start); - - if (s->use_copy_range) { - ret = block_copy_with_offload(s, start, dirty_end, - is_write_notifier); - if (ret < 0) { - s->use_copy_range = false; - } - } - if (!s->use_copy_range) { - ret = block_copy_with_bounce_buffer(s, start, dirty_end, - is_write_notifier, - error_is_read, &bounce_buffer); - } - if (ret < 0) { - break; - } - - start += ret; - s->progress_bytes_callback(ret, s->progress_opaque); - ret = 0; - } - - if (bounce_buffer) { - qemu_vfree(bounce_buffer); - } - - return ret; -} - static void backup_progress_bytes_callback(int64_t bytes, void *opaque) { BackupBlockJob *s = opaque; diff --git a/block/block-copy.c b/block/block-copy.c new file mode 100644 index 0000000000..c189318fcf --- /dev/null +++ b/block/block-copy.c @@ -0,0 +1,324 @@ +/* + * block_copy API + * + * Copyright (C) 2013 Proxmox Server Solutions + * Copyright (c) 2019 Virtuozzo International GmbH. + * + * Authors: + * Dietmar Maurer (dietmar@proxmox.com) + * Vladimir Sementsov-Ogievskiy + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + */ + +#include "qemu/osdep.h" + +#include "trace.h" +#include "qapi/error.h" +#include "block/block-copy.h" +#include "sysemu/block-backend.h" + +void block_copy_state_free(BlockCopyState *s) +{ + if (!s) { + return; + } + + bdrv_release_dirty_bitmap(blk_bs(s->source), s->copy_bitmap); + blk_unref(s->source); + blk_unref(s->target); + g_free(s); +} + +BlockCopyState *block_copy_state_new( + BlockDriverState *source, BlockDriverState *target, + int64_t cluster_size, BdrvRequestFlags write_flags, + ProgressBytesCallbackFunc progress_bytes_callback, + ProgressResetCallbackFunc progress_reset_callback, + void *progress_opaque, Error **errp) +{ + BlockCopyState *s; + int ret; + uint64_t no_resize = BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE | + BLK_PERM_WRITE_UNCHANGED | BLK_PERM_GRAPH_MOD; + BdrvDirtyBitmap *copy_bitmap; + + copy_bitmap = bdrv_create_dirty_bitmap(source, cluster_size, NULL, errp); + if (!copy_bitmap) { + return NULL; + } + bdrv_disable_dirty_bitmap(copy_bitmap); + + s = g_new(BlockCopyState, 1); + *s = (BlockCopyState) { + .source = blk_new(bdrv_get_aio_context(source), + BLK_PERM_CONSISTENT_READ, no_resize), + .target = blk_new(bdrv_get_aio_context(target), + BLK_PERM_WRITE, no_resize), + .copy_bitmap = copy_bitmap, + .cluster_size = cluster_size, + .len = bdrv_dirty_bitmap_size(copy_bitmap), + .write_flags = write_flags, + .use_copy_range = !(write_flags & BDRV_REQ_WRITE_COMPRESSED), + .progress_bytes_callback = progress_bytes_callback, + .progress_reset_callback = progress_reset_callback, + .progress_opaque = progress_opaque, + }; + + s->copy_range_size = QEMU_ALIGN_UP(MIN(blk_get_max_transfer(s->source), + blk_get_max_transfer(s->target)), + s->cluster_size); + + /* + * We just allow aio context change on our block backends. block_copy() user + * (now it's only backup) is responsible for source and target being in same + * aio context. + */ + blk_set_disable_request_queuing(s->source, true); + blk_set_allow_aio_context_change(s->source, true); + blk_set_disable_request_queuing(s->target, true); + blk_set_allow_aio_context_change(s->target, true); + + ret = blk_insert_bs(s->source, source, errp); + if (ret < 0) { + goto fail; + } + + ret = blk_insert_bs(s->target, target, errp); + if (ret < 0) { + goto fail; + } + + return s; + +fail: + block_copy_state_free(s); + + return NULL; +} + +/* + * Copy range to target with a bounce buffer and return the bytes copied. If + * error occurred, return a negative error number + */ +static int coroutine_fn block_copy_with_bounce_buffer(BlockCopyState *s, + int64_t start, + int64_t end, + bool is_write_notifier, + bool *error_is_read, + void **bounce_buffer) +{ + int ret; + int nbytes; + int read_flags = is_write_notifier ? BDRV_REQ_NO_SERIALISING : 0; + + assert(QEMU_IS_ALIGNED(start, s->cluster_size)); + bdrv_reset_dirty_bitmap(s->copy_bitmap, start, s->cluster_size); + nbytes = MIN(s->cluster_size, s->len - start); + if (!*bounce_buffer) { + *bounce_buffer = blk_blockalign(s->source, s->cluster_size); + } + + ret = blk_co_pread(s->source, start, nbytes, *bounce_buffer, read_flags); + if (ret < 0) { + trace_block_copy_with_bounce_buffer_read_fail(s, start, ret); + if (error_is_read) { + *error_is_read = true; + } + goto fail; + } + + ret = blk_co_pwrite(s->target, start, nbytes, *bounce_buffer, + s->write_flags); + if (ret < 0) { + trace_block_copy_with_bounce_buffer_write_fail(s, start, ret); + if (error_is_read) { + *error_is_read = false; + } + goto fail; + } + + return nbytes; +fail: + bdrv_set_dirty_bitmap(s->copy_bitmap, start, s->cluster_size); + return ret; + +} + +/* + * Copy range to target and return the bytes copied. If error occurred, return a + * negative error number. + */ +static int coroutine_fn block_copy_with_offload(BlockCopyState *s, + int64_t start, + int64_t end, + bool is_write_notifier) +{ + int ret; + int nr_clusters; + int nbytes; + int read_flags = is_write_notifier ? BDRV_REQ_NO_SERIALISING : 0; + + assert(QEMU_IS_ALIGNED(s->copy_range_size, s->cluster_size)); + assert(QEMU_IS_ALIGNED(start, s->cluster_size)); + nbytes = MIN(s->copy_range_size, MIN(end, s->len) - start); + nr_clusters = DIV_ROUND_UP(nbytes, s->cluster_size); + bdrv_reset_dirty_bitmap(s->copy_bitmap, start, + s->cluster_size * nr_clusters); + ret = blk_co_copy_range(s->source, start, s->target, start, nbytes, + read_flags, s->write_flags); + if (ret < 0) { + trace_block_copy_with_offload_fail(s, start, ret); + bdrv_set_dirty_bitmap(s->copy_bitmap, start, + s->cluster_size * nr_clusters); + return ret; + } + + return nbytes; +} + +/* + * Check if the cluster starting at offset is allocated or not. + * return via pnum the number of contiguous clusters sharing this allocation. + */ +static int block_copy_is_cluster_allocated(BlockCopyState *s, int64_t offset, + int64_t *pnum) +{ + BlockDriverState *bs = blk_bs(s->source); + int64_t count, total_count = 0; + int64_t bytes = s->len - offset; + int ret; + + assert(QEMU_IS_ALIGNED(offset, s->cluster_size)); + + while (true) { + ret = bdrv_is_allocated(bs, offset, bytes, &count); + if (ret < 0) { + return ret; + } + + total_count += count; + + if (ret || count == 0) { + /* + * ret: partial segment(s) are considered allocated. + * otherwise: unallocated tail is treated as an entire segment. + */ + *pnum = DIV_ROUND_UP(total_count, s->cluster_size); + return ret; + } + + /* Unallocated segment(s) with uncertain following segment(s) */ + if (total_count >= s->cluster_size) { + *pnum = total_count / s->cluster_size; + return 0; + } + + offset += count; + bytes -= count; + } +} + +/* + * Reset bits in copy_bitmap starting at offset if they represent unallocated + * data in the image. May reset subsequent contiguous bits. + * @return 0 when the cluster at @offset was unallocated, + * 1 otherwise, and -ret on error. + */ +int64_t block_copy_reset_unallocated(BlockCopyState *s, + int64_t offset, int64_t *count) +{ + int ret; + int64_t clusters, bytes; + + ret = block_copy_is_cluster_allocated(s, offset, &clusters); + if (ret < 0) { + return ret; + } + + bytes = clusters * s->cluster_size; + + if (!ret) { + bdrv_reset_dirty_bitmap(s->copy_bitmap, offset, bytes); + s->progress_reset_callback(s->progress_opaque); + } + + *count = bytes; + return ret; +} + +int coroutine_fn block_copy(BlockCopyState *s, + int64_t start, uint64_t bytes, + bool *error_is_read, + bool is_write_notifier) +{ + int ret = 0; + int64_t end = bytes + start; /* bytes */ + void *bounce_buffer = NULL; + int64_t status_bytes; + + /* + * block_copy() user is responsible for keeping source and target in same + * aio context + */ + assert(blk_get_aio_context(s->source) == blk_get_aio_context(s->target)); + + assert(QEMU_IS_ALIGNED(start, s->cluster_size)); + assert(QEMU_IS_ALIGNED(end, s->cluster_size)); + + while (start < end) { + int64_t dirty_end; + + if (!bdrv_dirty_bitmap_get(s->copy_bitmap, start)) { + trace_block_copy_skip(s, start); + start += s->cluster_size; + continue; /* already copied */ + } + + dirty_end = bdrv_dirty_bitmap_next_zero(s->copy_bitmap, start, + (end - start)); + if (dirty_end < 0) { + dirty_end = end; + } + + if (s->skip_unallocated) { + ret = block_copy_reset_unallocated(s, start, &status_bytes); + if (ret == 0) { + trace_block_copy_skip_range(s, start, status_bytes); + start += status_bytes; + continue; + } + /* Clamp to known allocated region */ + dirty_end = MIN(dirty_end, start + status_bytes); + } + + trace_block_copy_process(s, start); + + if (s->use_copy_range) { + ret = block_copy_with_offload(s, start, dirty_end, + is_write_notifier); + if (ret < 0) { + s->use_copy_range = false; + } + } + if (!s->use_copy_range) { + ret = block_copy_with_bounce_buffer(s, start, dirty_end, + is_write_notifier, + error_is_read, &bounce_buffer); + } + if (ret < 0) { + break; + } + + start += ret; + s->progress_bytes_callback(ret, s->progress_opaque); + ret = 0; + } + + if (bounce_buffer) { + qemu_vfree(bounce_buffer); + } + + return ret; +} diff --git a/block/Makefile.objs b/block/Makefile.objs index 35f3bca4d9..0b5c635fb2 100644 --- a/block/Makefile.objs +++ b/block/Makefile.objs @@ -37,6 +37,7 @@ block-obj-y += write-threshold.o block-obj-y += backup.o block-obj-$(CONFIG_REPLICATION) += replication.o block-obj-y += throttle.o copy-on-read.o +block-obj-y += block-copy.o block-obj-y += crypto.o diff --git a/block/trace-events b/block/trace-events index 6e7532f48b..bbf82f069e 100644 --- a/block/trace-events +++ b/block/trace-events @@ -40,6 +40,8 @@ mirror_yield_in_flight(void *s, int64_t offset, int in_flight) "s %p offset %" P # backup.c backup_do_cow_enter(void *job, int64_t start, int64_t offset, uint64_t bytes) "job %p start %" PRId64 " offset %" PRId64 " bytes %" PRIu64 backup_do_cow_return(void *job, int64_t offset, uint64_t bytes, int ret) "job %p offset %" PRId64 " bytes %" PRIu64 " ret %d" + +# block-copy.c block_copy_skip(void *bcs, int64_t start) "bcs %p start %"PRId64 block_copy_skip_range(void *bcs, int64_t start, uint64_t bytes) "bcs %p start %"PRId64" bytes %"PRId64 block_copy_process(void *bcs, int64_t start) "bcs %p start %"PRId64