mirror of
https://gitlab.com/qemu-project/qemu
synced 2024-09-06 18:05:37 +00:00
block: move block_copy from block/backup.c to separate file
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 <vsementsov@virtuozzo.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Message-id: 20190920142056.12778-8-vsementsov@virtuozzo.com Signed-off-by: Max Reitz <mreitz@redhat.com>
This commit is contained in:
parent
0e23e382b7
commit
beb5f5450d
|
@ -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
|
||||
|
||||
|
|
355
block/backup.c
355
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;
|
||||
|
@ -135,319 +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,
|
||||
.progress_bytes_callback = progress_bytes_callback,
|
||||
.progress_reset_callback = progress_reset_callback,
|
||||
.progress_opaque = progress_opaque,
|
||||
};
|
||||
|
||||
s->copy_range_size = QEMU_ALIGN_DOWN(MIN(blk_get_max_transfer(s->source),
|
||||
blk_get_max_transfer(s->target)),
|
||||
s->cluster_size);
|
||||
/*
|
||||
* Set use_copy_range, consider the following:
|
||||
* 1. Compression is not supported for copy_range.
|
||||
* 2. copy_range does not respect max_transfer (it's a TODO), so we factor
|
||||
* that in here. If max_transfer is smaller than the job->cluster_size,
|
||||
* we do not use copy_range (in that case it's zero after aligning down
|
||||
* above).
|
||||
*/
|
||||
s->use_copy_range =
|
||||
!(write_flags & BDRV_REQ_WRITE_COMPRESSED) && s->copy_range_size > 0;
|
||||
|
||||
/*
|
||||
* 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;
|
||||
|
|
333
block/block-copy.c
Normal file
333
block/block-copy.c
Normal file
|
@ -0,0 +1,333 @@
|
|||
/*
|
||||
* block_copy API
|
||||
*
|
||||
* Copyright (C) 2013 Proxmox Server Solutions
|
||||
* Copyright (c) 2019 Virtuozzo International GmbH.
|
||||
*
|
||||
* Authors:
|
||||
* Dietmar Maurer (dietmar@proxmox.com)
|
||||
* Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
|
||||
*
|
||||
* 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,
|
||||
.progress_bytes_callback = progress_bytes_callback,
|
||||
.progress_reset_callback = progress_reset_callback,
|
||||
.progress_opaque = progress_opaque,
|
||||
};
|
||||
|
||||
s->copy_range_size = QEMU_ALIGN_DOWN(MIN(blk_get_max_transfer(s->source),
|
||||
blk_get_max_transfer(s->target)),
|
||||
s->cluster_size);
|
||||
/*
|
||||
* Set use_copy_range, consider the following:
|
||||
* 1. Compression is not supported for copy_range.
|
||||
* 2. copy_range does not respect max_transfer (it's a TODO), so we factor
|
||||
* that in here. If max_transfer is smaller than the job->cluster_size,
|
||||
* we do not use copy_range (in that case it's zero after aligning down
|
||||
* above).
|
||||
*/
|
||||
s->use_copy_range =
|
||||
!(write_flags & BDRV_REQ_WRITE_COMPRESSED) && s->copy_range_size > 0;
|
||||
|
||||
/*
|
||||
* 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;
|
||||
}
|
|
@ -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
|
||||
|
|
76
include/block/block-copy.h
Normal file
76
include/block/block-copy.h
Normal file
|
@ -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 <vsementsov@virtuozzo.com>
|
||||
*
|
||||
* 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 */
|
Loading…
Reference in a new issue