#include "qemu/osdep.h"
#include "trace.h"
#include "block/block_int.h"
-#include "block/blockjob.h"
+#include "block/blockjob_int.h"
#include "qapi/error.h"
#include "qapi/qmp/qerror.h"
#include "qemu/ratelimit.h"
BlockDriverState *base;
BlockdevOnError on_error;
char *backing_file_str;
+ int bs_flags;
} StreamBlockJob;
static int coroutine_fn stream_populate(BlockBackend *blk,
- int64_t sector_num, int nb_sectors,
+ int64_t offset, uint64_t bytes,
void *buf)
{
struct iovec iov = {
.iov_base = buf,
- .iov_len = nb_sectors * BDRV_SECTOR_SIZE,
+ .iov_len = bytes,
};
QEMUIOVector qiov;
+ assert(bytes < SIZE_MAX);
qemu_iovec_init_external(&qiov, &iov, 1);
/* Copy-on-read the unallocated clusters */
- return blk_co_preadv(blk, sector_num * BDRV_SECTOR_SIZE, qiov.size, &qiov,
- BDRV_REQ_COPY_ON_READ);
+ return blk_co_preadv(blk, offset, qiov.size, &qiov, BDRV_REQ_COPY_ON_READ);
}
typedef struct {
int ret;
- bool reached_end;
} StreamCompleteData;
static void stream_complete(BlockJob *job, void *opaque)
StreamCompleteData *data = opaque;
BlockDriverState *bs = blk_bs(job->blk);
BlockDriverState *base = s->base;
+ Error *local_err = NULL;
- if (!block_job_is_cancelled(&s->common) && data->reached_end &&
+ if (!block_job_is_cancelled(&s->common) && bs->backing &&
data->ret == 0) {
const char *base_id = NULL, *base_fmt = NULL;
if (base) {
}
}
data->ret = bdrv_change_backing_file(bs, base_id, base_fmt);
- bdrv_set_backing_hd(bs, base);
+ bdrv_set_backing_hd(bs, base, &local_err);
+ if (local_err) {
+ error_report_err(local_err);
+ data->ret = -EPERM;
+ goto out;
+ }
+ }
+
+out:
+ /* Reopen the image back in read-only mode if necessary */
+ if (s->bs_flags != bdrv_get_flags(bs)) {
+ /* Give up write permissions before making it read-only */
+ blk_set_perm(job->blk, 0, BLK_PERM_ALL, &error_abort);
+ bdrv_reopen(bs, s->bs_flags, NULL);
}
g_free(s->backing_file_str);
BlockBackend *blk = s->common.blk;
BlockDriverState *bs = blk_bs(blk);
BlockDriverState *base = s->base;
- int64_t sector_num = 0;
- int64_t end = -1;
+ int64_t offset = 0;
+ uint64_t delay_ns = 0;
int error = 0;
int ret = 0;
- int n = 0;
+ int64_t n = 0; /* bytes */
void *buf;
if (!bs->backing) {
goto out;
}
- end = s->common.len >> BDRV_SECTOR_BITS;
buf = qemu_blockalign(bs, STREAM_BUFFER_SIZE);
/* Turn on copy-on-read for the whole block device so that guest read
bdrv_enable_copy_on_read(bs);
}
- for (sector_num = 0; sector_num < end; sector_num += n) {
- uint64_t delay_ns = 0;
+ for ( ; offset < s->common.len; offset += n) {
bool copy;
-wait:
/* Note that even when no rate limit is applied we need to yield
* with no pending I/O here so that bdrv_drain_all() returns.
*/
- block_job_sleep_ns(&s->common, QEMU_CLOCK_REALTIME, delay_ns);
+ block_job_sleep_ns(&s->common, delay_ns);
if (block_job_is_cancelled(&s->common)) {
break;
}
copy = false;
- ret = bdrv_is_allocated(bs, sector_num,
- STREAM_BUFFER_SIZE / BDRV_SECTOR_SIZE, &n);
+ ret = bdrv_is_allocated(bs, offset, STREAM_BUFFER_SIZE, &n);
if (ret == 1) {
/* Allocated in the top, no need to copy. */
} else if (ret >= 0) {
/* Copy if allocated in the intermediate images. Limit to the
- * known-unallocated area [sector_num, sector_num+n). */
+ * known-unallocated area [offset, offset+n*BDRV_SECTOR_SIZE). */
ret = bdrv_is_allocated_above(backing_bs(bs), base,
- sector_num, n, &n);
+ offset, n, &n);
/* Finish early if end of backing file has been reached */
if (ret == 0 && n == 0) {
- n = end - sector_num;
+ n = s->common.len - offset;
}
copy = (ret == 1);
}
- trace_stream_one_iteration(s, sector_num, n, ret);
+ trace_stream_one_iteration(s, offset, n, ret);
if (copy) {
- if (s->common.speed) {
- delay_ns = ratelimit_calculate_delay(&s->limit, n);
- if (delay_ns > 0) {
- goto wait;
- }
- }
- ret = stream_populate(blk, sector_num, n, buf);
+ ret = stream_populate(blk, offset, n, buf);
}
if (ret < 0) {
BlockErrorAction action =
ret = 0;
/* Publish progress */
- s->common.offset += n * BDRV_SECTOR_SIZE;
+ s->common.offset += n;
+ if (copy && s->common.speed) {
+ delay_ns = ratelimit_calculate_delay(&s->limit, n);
+ }
}
if (!base) {
/* Modify backing chain and close BDSes in main loop */
data = g_malloc(sizeof(*data));
data->ret = ret;
- data->reached_end = sector_num == end;
block_job_defer_to_main_loop(&s->common, stream_complete, data);
}
error_setg(errp, QERR_INVALID_PARAMETER, "speed");
return;
}
- ratelimit_set_speed(&s->limit, speed / BDRV_SECTOR_SIZE, SLICE_TIME);
+ ratelimit_set_speed(&s->limit, speed, SLICE_TIME);
}
static const BlockJobDriver stream_job_driver = {
.instance_size = sizeof(StreamBlockJob),
.job_type = BLOCK_JOB_TYPE_STREAM,
.set_speed = stream_set_speed,
+ .start = stream_run,
};
void stream_start(const char *job_id, BlockDriverState *bs,
BlockDriverState *base, const char *backing_file_str,
- int64_t speed, BlockdevOnError on_error,
- BlockCompletionFunc *cb, void *opaque, Error **errp)
+ int64_t speed, BlockdevOnError on_error, Error **errp)
{
StreamBlockJob *s;
+ BlockDriverState *iter;
+ int orig_bs_flags;
+
+ /* Make sure that the image is opened in read-write mode */
+ orig_bs_flags = bdrv_get_flags(bs);
+ if (!(orig_bs_flags & BDRV_O_RDWR)) {
+ if (bdrv_reopen(bs, orig_bs_flags | BDRV_O_RDWR, errp) != 0) {
+ return;
+ }
+ }
- s = block_job_create(job_id, &stream_job_driver, bs, speed,
- cb, opaque, errp);
+ /* Prevent concurrent jobs trying to modify the graph structure here, we
+ * already have our own plans. Also don't allow resize as the image size is
+ * queried only at the job start and then cached. */
+ s = block_job_create(job_id, &stream_job_driver, NULL, bs,
+ BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE_UNCHANGED |
+ BLK_PERM_GRAPH_MOD,
+ BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE_UNCHANGED |
+ BLK_PERM_WRITE,
+ speed, BLOCK_JOB_DEFAULT, NULL, NULL, errp);
if (!s) {
- return;
+ goto fail;
+ }
+
+ /* Block all intermediate nodes between bs and base, because they will
+ * disappear from the chain after this operation. The streaming job reads
+ * every block only once, assuming that it doesn't change, so block writes
+ * and resizes. */
+ for (iter = backing_bs(bs); iter && iter != base; iter = backing_bs(iter)) {
+ block_job_add_bdrv(&s->common, "intermediate node", iter, 0,
+ BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE_UNCHANGED,
+ &error_abort);
}
s->base = base;
s->backing_file_str = g_strdup(backing_file_str);
+ s->bs_flags = orig_bs_flags;
s->on_error = on_error;
- s->common.co = qemu_coroutine_create(stream_run, s);
- trace_stream_start(bs, base, s, s->common.co, opaque);
- qemu_coroutine_enter(s->common.co);
+ trace_stream_start(bs, base, s);
+ block_job_start(&s->common);
+ return;
+
+fail:
+ if (orig_bs_flags != bdrv_get_flags(bs)) {
+ bdrv_reopen(bs, orig_bs_flags, NULL);
+ }
}
projects / qemu.git / blobdiff