Merge remote-tracking branch 'remotes/maxreitz/tags/pull-block-2019-10-10' into staging (088d6709) · Commits · SUMMER2020 / students / proj-2021291

block.c

+35 −8

Original line number	Diff line number	Diff line
		@@ -5155,6 +5155,15 @@ ImageInfoSpecific bdrv_get_specific_info(BlockDriverState bs,
		return NULL;
		}

		BlockStatsSpecific bdrv_get_specific_stats(BlockDriverState bs)
		{
		BlockDriver *drv = bs->drv;
		if (!drv \|\| !drv->bdrv_get_specific_stats) {
		return NULL;
		}
		return drv->bdrv_get_specific_stats(bs);
		}

		void bdrv_debug_event(BlockDriverState *bs, BlkdebugEvent event)
		{
		if (!bs \|\| !bs->drv \|\| !bs->drv->bdrv_debug_event) {
		@@ -5164,14 +5173,35 @@ void bdrv_debug_event(BlockDriverState *bs, BlkdebugEvent event)
		bs->drv->bdrv_debug_event(bs, event);
		}

		int bdrv_debug_breakpoint(BlockDriverState bs, const char event,
		const char *tag)
		static BlockDriverState bdrv_find_debug_node(BlockDriverState bs)
		{
		while (bs && bs->drv && !bs->drv->bdrv_debug_breakpoint) {
		bs = bs->file ? bs->file->bs : NULL;
		if (bs->file) {
		bs = bs->file->bs;
		continue;
		}

		if (bs->drv->is_filter && bs->backing) {
		bs = bs->backing->bs;
		continue;
		}

		break;
		}

		if (bs && bs->drv && bs->drv->bdrv_debug_breakpoint) {
		assert(bs->drv->bdrv_debug_remove_breakpoint);
		return bs;
		}

		return NULL;
		}

		int bdrv_debug_breakpoint(BlockDriverState bs, const char event,
		const char *tag)
		{
		bs = bdrv_find_debug_node(bs);
		if (bs) {
		return bs->drv->bdrv_debug_breakpoint(bs, event, tag);
		}

		@@ -5180,11 +5210,8 @@ int bdrv_debug_breakpoint(BlockDriverState bs, const char event,

		int bdrv_debug_remove_breakpoint(BlockDriverState bs, const char tag)
		{
		while (bs && bs->drv && !bs->drv->bdrv_debug_remove_breakpoint) {
		bs = bs->file ? bs->file->bs : NULL;
		}

		if (bs && bs->drv && bs->drv->bdrv_debug_remove_breakpoint) {
		bs = bdrv_find_debug_node(bs);
		if (bs) {
		return bs->drv->bdrv_debug_remove_breakpoint(bs, tag);
		}

block/Makefile.objs

+4 −0

Original line number	Diff line number	Diff line
		@@ -37,9 +37,13 @@ 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

		block-obj-y += aio_task.o
		block-obj-y += backup-top.o

		common-obj-y += stream.o

		nfs.o-libs := $(LIBNFS_LIBS)

block/accounting.c

+6 −0

Original line number	Diff line number	Diff line
		@@ -195,6 +195,10 @@ static void block_account_one_io(BlockAcctStats stats, BlockAcctCookie cookie,

		assert(cookie->type < BLOCK_MAX_IOTYPE);

		if (cookie->type == BLOCK_ACCT_NONE) {
		return;
		}

		qemu_mutex_lock(&stats->lock);

		if (failed) {
		@@ -217,6 +221,8 @@ static void block_account_one_io(BlockAcctStats stats, BlockAcctCookie cookie,
		}

		qemu_mutex_unlock(&stats->lock);

		cookie->type = BLOCK_ACCT_NONE;
		}

		void block_acct_done(BlockAcctStats stats, BlockAcctCookie cookie)

block/aio_task.c

0 → 100644

+124 −0

Original line number	Diff line number	Diff line
		/*
		* Aio tasks loops
		*
		* Copyright (c) 2019 Virtuozzo International GmbH.
		*
		* Permission is hereby granted, free of charge, to any person obtaining a copy
		* of this software and associated documentation files (the "Software"), to deal
		* in the Software without restriction, including without limitation the rights
		* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
		* copies of the Software, and to permit persons to whom the Software is
		* furnished to do so, subject to the following conditions:
		*
		* The above copyright notice and this permission notice shall be included in
		* all copies or substantial portions of the Software.
		*
		* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
		* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
		* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
		* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
		* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
		* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
		* THE SOFTWARE.
		*/

		#include "qemu/osdep.h"
		#include "block/aio.h"
		#include "block/aio_task.h"

		struct AioTaskPool {
		Coroutine *main_co;
		int status;
		int max_busy_tasks;
		int busy_tasks;
		bool waiting;
		};

		static void coroutine_fn aio_task_co(void *opaque)
		{
		AioTask *task = opaque;
		AioTaskPool *pool = task->pool;

		assert(pool->busy_tasks < pool->max_busy_tasks);
		pool->busy_tasks++;

		task->ret = task->func(task);

		pool->busy_tasks--;

		if (task->ret < 0 && pool->status == 0) {
		pool->status = task->ret;
		}

		g_free(task);

		if (pool->waiting) {
		pool->waiting = false;
		aio_co_wake(pool->main_co);
		}
		}

		void coroutine_fn aio_task_pool_wait_one(AioTaskPool *pool)
		{
		assert(pool->busy_tasks > 0);
		assert(qemu_coroutine_self() == pool->main_co);

		pool->waiting = true;
		qemu_coroutine_yield();

		assert(!pool->waiting);
		assert(pool->busy_tasks < pool->max_busy_tasks);
		}

		void coroutine_fn aio_task_pool_wait_slot(AioTaskPool *pool)
		{
		if (pool->busy_tasks < pool->max_busy_tasks) {
		return;
		}

		aio_task_pool_wait_one(pool);
		}

		void coroutine_fn aio_task_pool_wait_all(AioTaskPool *pool)
		{
		while (pool->busy_tasks > 0) {
		aio_task_pool_wait_one(pool);
		}
		}

		void coroutine_fn aio_task_pool_start_task(AioTaskPool pool, AioTask task)
		{
		aio_task_pool_wait_slot(pool);

		task->pool = pool;
		qemu_coroutine_enter(qemu_coroutine_create(aio_task_co, task));
		}

		AioTaskPool *coroutine_fn aio_task_pool_new(int max_busy_tasks)
		{
		AioTaskPool *pool = g_new0(AioTaskPool, 1);

		pool->main_co = qemu_coroutine_self();
		pool->max_busy_tasks = max_busy_tasks;

		return pool;
		}

		void aio_task_pool_free(AioTaskPool *pool)
		{
		g_free(pool);
		}

		int aio_task_pool_status(AioTaskPool *pool)
		{
		if (!pool) {
		return 0; /* Sugar for lazy allocation of aio pool */
		}

		return pool->status;
		}

		bool aio_task_pool_empty(AioTaskPool *pool)
		{
		return pool->busy_tasks == 0;
		}

block/backup-top.c

0 → 100644

+276 −0

Original line number	Diff line number	Diff line
		/*
		* backup-top filter driver
		*
		* The driver performs Copy-Before-Write (CBW) operation: it is injected above
		* some node, and before each write it copies _old_ data to the target node.
		*
		* Copyright (c) 2018-2019 Virtuozzo International GmbH.
		*
		* Author:
		* Sementsov-Ogievskiy Vladimir <vsementsov@virtuozzo.com>
		*
		* This program is free software; you can redistribute it and/or modify
		* it under the terms of the GNU General Public License as published by
		* the Free Software Foundation; either version 2 of the License, or
		* (at your option) any later version.
		*
		* This program is distributed in the hope that it will be useful,
		* but WITHOUT ANY WARRANTY; without even the implied warranty of
		* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
		* GNU General Public License for more details.
		*
		* You should have received a copy of the GNU General Public License
		* along with this program. If not, see <http://www.gnu.org/licenses/>.
		*/

		#include "qemu/osdep.h"

		#include "sysemu/block-backend.h"
		#include "qemu/cutils.h"
		#include "qapi/error.h"
		#include "block/block_int.h"
		#include "block/qdict.h"
		#include "block/block-copy.h"

		#include "block/backup-top.h"

		typedef struct BDRVBackupTopState {
		BlockCopyState *bcs;
		BdrvChild *target;
		bool active;
		} BDRVBackupTopState;

		static coroutine_fn int backup_top_co_preadv(
		BlockDriverState *bs, uint64_t offset, uint64_t bytes,
		QEMUIOVector *qiov, int flags)
		{
		return bdrv_co_preadv(bs->backing, offset, bytes, qiov, flags);
		}

		static coroutine_fn int backup_top_cbw(BlockDriverState *bs, uint64_t offset,
		uint64_t bytes)
		{
		BDRVBackupTopState *s = bs->opaque;
		uint64_t end = QEMU_ALIGN_UP(offset + bytes, s->bcs->cluster_size);
		uint64_t off = QEMU_ALIGN_DOWN(offset, s->bcs->cluster_size);

		return block_copy(s->bcs, off, end - off, NULL);
		}

		static int coroutine_fn backup_top_co_pdiscard(BlockDriverState *bs,
		int64_t offset, int bytes)
		{
		int ret = backup_top_cbw(bs, offset, bytes);
		if (ret < 0) {
		return ret;
		}

		return bdrv_co_pdiscard(bs->backing, offset, bytes);
		}

		static int coroutine_fn backup_top_co_pwrite_zeroes(BlockDriverState *bs,
		int64_t offset, int bytes, BdrvRequestFlags flags)
		{
		int ret = backup_top_cbw(bs, offset, bytes);
		if (ret < 0) {
		return ret;
		}

		return bdrv_co_pwrite_zeroes(bs->backing, offset, bytes, flags);
		}

		static coroutine_fn int backup_top_co_pwritev(BlockDriverState *bs,
		uint64_t offset,
		uint64_t bytes,
		QEMUIOVector *qiov, int flags)
		{
		if (!(flags & BDRV_REQ_WRITE_UNCHANGED)) {
		int ret = backup_top_cbw(bs, offset, bytes);
		if (ret < 0) {
		return ret;
		}
		}

		return bdrv_co_pwritev(bs->backing, offset, bytes, qiov, flags);
		}

		static int coroutine_fn backup_top_co_flush(BlockDriverState *bs)
		{
		if (!bs->backing) {
		return 0;
		}

		return bdrv_co_flush(bs->backing->bs);
		}

		static void backup_top_refresh_filename(BlockDriverState *bs)
		{
		if (bs->backing == NULL) {
		/*
		* we can be here after failed bdrv_attach_child in
		* bdrv_set_backing_hd
		*/
		return;
		}
		pstrcpy(bs->exact_filename, sizeof(bs->exact_filename),
		bs->backing->bs->filename);
		}

		static void backup_top_child_perm(BlockDriverState bs, BdrvChild c,
		const BdrvChildRole *role,
		BlockReopenQueue *reopen_queue,
		uint64_t perm, uint64_t shared,
		uint64_t nperm, uint64_t nshared)
		{
		BDRVBackupTopState *s = bs->opaque;

		if (!s->active) {
		/*
		* The filter node may be in process of bdrv_append(), which firstly do
		* bdrv_set_backing_hd() and then bdrv_replace_node(). This means that
		* we can't unshare BLK_PERM_WRITE during bdrv_append() operation. So,
		* let's require nothing during bdrv_append() and refresh permissions
		* after it (see bdrv_backup_top_append()).
		*/
		*nperm = 0;
		*nshared = BLK_PERM_ALL;
		return;
		}

		if (role == &child_file) {
		/*
		* Target child
		*
		* Share write to target (child_file), to not interfere
		* with guest writes to its disk which may be in target backing chain.
		*/
		*nshared = BLK_PERM_ALL;
		*nperm = BLK_PERM_WRITE;
		} else {
		/* Source child */
		bdrv_filter_default_perms(bs, c, role, reopen_queue, perm, shared,
		nperm, nshared);

		if (perm & BLK_PERM_WRITE) {
		nperm = nperm \| BLK_PERM_CONSISTENT_READ;
		}
		*nshared &= ~BLK_PERM_WRITE;
		}
		}

		BlockDriver bdrv_backup_top_filter = {
		.format_name = "backup-top",
		.instance_size = sizeof(BDRVBackupTopState),

		.bdrv_co_preadv = backup_top_co_preadv,
		.bdrv_co_pwritev = backup_top_co_pwritev,
		.bdrv_co_pwrite_zeroes = backup_top_co_pwrite_zeroes,
		.bdrv_co_pdiscard = backup_top_co_pdiscard,
		.bdrv_co_flush = backup_top_co_flush,

		.bdrv_co_block_status = bdrv_co_block_status_from_backing,

		.bdrv_refresh_filename = backup_top_refresh_filename,

		.bdrv_child_perm = backup_top_child_perm,

		.is_filter = true,
		};

		BlockDriverState bdrv_backup_top_append(BlockDriverState source,
		BlockDriverState *target,
		const char *filter_node_name,
		uint64_t cluster_size,
		BdrvRequestFlags write_flags,
		BlockCopyState **bcs,
		Error **errp)
		{
		Error *local_err = NULL;
		BDRVBackupTopState *state;
		BlockDriverState *top = bdrv_new_open_driver(&bdrv_backup_top_filter,
		filter_node_name,
		BDRV_O_RDWR, errp);

		if (!top) {
		return NULL;
		}

		top->total_sectors = source->total_sectors;
		top->opaque = state = g_new0(BDRVBackupTopState, 1);

		bdrv_ref(target);
		state->target = bdrv_attach_child(top, target, "target", &child_file, errp);
		if (!state->target) {
		bdrv_unref(target);
		bdrv_unref(top);
		return NULL;
		}

		bdrv_drained_begin(source);

		bdrv_ref(top);
		bdrv_append(top, source, &local_err);
		if (local_err) {
		error_prepend(&local_err, "Cannot append backup-top filter: ");
		goto append_failed;
		}

		/*
		* bdrv_append() finished successfully, now we can require permissions
		* we want.
		*/
		state->active = true;
		bdrv_child_refresh_perms(top, top->backing, &local_err);
		if (local_err) {
		error_prepend(&local_err,
		"Cannot set permissions for backup-top filter: ");
		goto failed_after_append;
		}

		state->bcs = block_copy_state_new(top->backing, state->target,
		cluster_size, write_flags, &local_err);
		if (local_err) {
		error_prepend(&local_err, "Cannot create block-copy-state: ");
		goto failed_after_append;
		}
		*bcs = state->bcs;

		bdrv_drained_end(source);

		return top;

		failed_after_append:
		state->active = false;
		bdrv_backup_top_drop(top);

		append_failed:
		bdrv_drained_end(source);
		bdrv_unref_child(top, state->target);
		bdrv_unref(top);
		error_propagate(errp, local_err);

		return NULL;
		}

		void bdrv_backup_top_drop(BlockDriverState *bs)
		{
		BDRVBackupTopState *s = bs->opaque;
		AioContext *aio_context = bdrv_get_aio_context(bs);

		block_copy_state_free(s->bcs);

		aio_context_acquire(aio_context);

		bdrv_drained_begin(bs);

		s->active = false;
		bdrv_child_refresh_perms(bs, bs->backing, &error_abort);
		bdrv_replace_node(bs, backing_bs(bs), &error_abort);
		bdrv_set_backing_hd(bs, NULL, &error_abort);

		bdrv_drained_end(bs);

		bdrv_unref(bs);

		aio_context_release(aio_context);
		}