bs->slice_start = 0;
bs->slice_end = 0;
- bs->slice_time = 0;
}
static void bdrv_block_timer(void *opaque)
* Removes all processed options from *options.
*/
static int bdrv_open_common(BlockDriverState *bs, BlockDriverState *file,
- const char *filename, QDict *options,
- int flags, BlockDriver *drv)
+ QDict *options, int flags, BlockDriver *drv)
{
int ret, open_flags;
+ const char *filename;
assert(drv != NULL);
assert(bs->file == NULL);
assert(options != NULL && bs->options != options);
- trace_bdrv_open_common(bs, filename, flags, drv->format_name);
+ if (file != NULL) {
+ filename = file->filename;
+ } else {
+ filename = qdict_get_try_str(options, "filename");
+ }
+
+ trace_bdrv_open_common(bs, filename ?: "", flags, drv->format_name);
if (use_bdrv_whitelist && !bdrv_is_whitelisted(drv)) {
return -ENOTSUP;
if (drv->bdrv_file_open) {
assert(file == NULL);
assert(drv->bdrv_parse_filename || filename != NULL);
- ret = drv->bdrv_file_open(bs, filename, options, open_flags);
+ ret = drv->bdrv_file_open(bs, options, open_flags);
} else {
+ if (file == NULL) {
+ qerror_report(ERROR_CLASS_GENERIC_ERROR, "Can't use '%s' as a "
+ "block driver for the protocol level",
+ drv->format_name);
+ ret = -EINVAL;
+ goto free_and_fail;
+ }
assert(file != NULL);
bs->file = file;
ret = drv->bdrv_open(bs, options, open_flags);
bs->options = options;
options = qdict_clone_shallow(options);
+ /* Fetch the file name from the options QDict if necessary */
+ if (!filename) {
+ filename = qdict_get_try_str(options, "filename");
+ } else if (filename && !qdict_haskey(options, "filename")) {
+ qdict_put(options, "filename", qstring_from_str(filename));
+ } else {
+ qerror_report(ERROR_CLASS_GENERIC_ERROR, "Can't specify 'file' and "
+ "'filename' options at the same time");
+ ret = -EINVAL;
+ goto fail;
+ }
+
/* Find the right block driver */
drvname = qdict_get_try_str(options, "driver");
if (drvname) {
ret = -EINVAL;
goto fail;
}
+ qdict_del(options, "filename");
} else if (!drv->bdrv_parse_filename && !filename) {
qerror_report(ERROR_CLASS_GENERIC_ERROR,
"The '%s' block driver requires a file name",
goto fail;
}
- ret = bdrv_open_common(bs, NULL, filename, options, flags, drv);
+ ret = bdrv_open_common(bs, NULL, options, flags, drv);
if (ret < 0) {
goto fail;
}
return ret;
}
-int bdrv_open_backing_file(BlockDriverState *bs)
+/*
+ * Opens the backing file for a BlockDriverState if not yet open
+ *
+ * options is a QDict of options to pass to the block drivers, or NULL for an
+ * empty set of options. The reference to the QDict is transferred to this
+ * function (even on failure), so if the caller intends to reuse the dictionary,
+ * it needs to use QINCREF() before calling bdrv_file_open.
+ */
+int bdrv_open_backing_file(BlockDriverState *bs, QDict *options)
{
char backing_filename[PATH_MAX];
int back_flags, ret;
BlockDriver *back_drv = NULL;
if (bs->backing_hd != NULL) {
+ QDECREF(options);
return 0;
}
+ /* NULL means an empty set of options */
+ if (options == NULL) {
+ options = qdict_new();
+ }
+
bs->open_flags &= ~BDRV_O_NO_BACKING;
- if (bs->backing_file[0] == '\0') {
+ if (qdict_haskey(options, "file.filename")) {
+ backing_filename[0] = '\0';
+ } else if (bs->backing_file[0] == '\0' && qdict_size(options) == 0) {
+ QDECREF(options);
return 0;
}
/* backing files always opened read-only */
back_flags = bs->open_flags & ~(BDRV_O_RDWR | BDRV_O_SNAPSHOT);
- ret = bdrv_open(bs->backing_hd, backing_filename, NULL,
+ ret = bdrv_open(bs->backing_hd,
+ *backing_filename ? backing_filename : NULL, options,
back_flags, back_drv);
if (ret < 0) {
bdrv_delete(bs->backing_hd);
}
/* Open the image */
- ret = bdrv_open_common(bs, file, filename, options, flags, drv);
+ ret = bdrv_open_common(bs, file, options, flags, drv);
if (ret < 0) {
goto unlink_and_fail;
}
/* If there is a backing file, use it */
if ((flags & BDRV_O_NO_BACKING) == 0) {
- ret = bdrv_open_backing_file(bs);
+ QDict *backing_options;
+
+ extract_subqdict(options, &backing_options, "backing.");
+ ret = bdrv_open_backing_file(bs, backing_options);
if (ret < 0) {
goto close_and_fail;
}
bs_dest->enable_write_cache = bs_src->enable_write_cache;
/* i/o timing parameters */
- bs_dest->slice_time = bs_src->slice_time;
bs_dest->slice_start = bs_src->slice_start;
bs_dest->slice_end = bs_src->slice_end;
bs_dest->slice_submitted = bs_src->slice_submitted;
}
/*
- * Process a synchronous request using coroutines
+ * Process a vectored synchronous request using coroutines
*/
-static int bdrv_rw_co(BlockDriverState *bs, int64_t sector_num, uint8_t *buf,
- int nb_sectors, bool is_write)
+static int bdrv_rwv_co(BlockDriverState *bs, int64_t sector_num,
+ QEMUIOVector *qiov, bool is_write)
{
- QEMUIOVector qiov;
- struct iovec iov = {
- .iov_base = (void *)buf,
- .iov_len = nb_sectors * BDRV_SECTOR_SIZE,
- };
Coroutine *co;
RwCo rwco = {
.bs = bs,
.sector_num = sector_num,
- .nb_sectors = nb_sectors,
- .qiov = &qiov,
+ .nb_sectors = qiov->size >> BDRV_SECTOR_BITS,
+ .qiov = qiov,
.is_write = is_write,
.ret = NOT_DONE,
};
-
- qemu_iovec_init_external(&qiov, &iov, 1);
+ assert((qiov->size & (BDRV_SECTOR_SIZE - 1)) == 0);
/**
* In sync call context, when the vcpu is blocked, this throttling timer
return rwco.ret;
}
+/*
+ * Process a synchronous request using coroutines
+ */
+static int bdrv_rw_co(BlockDriverState *bs, int64_t sector_num, uint8_t *buf,
+ int nb_sectors, bool is_write)
+{
+ QEMUIOVector qiov;
+ struct iovec iov = {
+ .iov_base = (void *)buf,
+ .iov_len = nb_sectors * BDRV_SECTOR_SIZE,
+ };
+
+ qemu_iovec_init_external(&qiov, &iov, 1);
+ return bdrv_rwv_co(bs, sector_num, &qiov, is_write);
+}
+
/* return < 0 if error. See bdrv_write() for the return codes */
int bdrv_read(BlockDriverState *bs, int64_t sector_num,
uint8_t *buf, int nb_sectors)
return bdrv_rw_co(bs, sector_num, (uint8_t *)buf, nb_sectors, true);
}
+int bdrv_writev(BlockDriverState *bs, int64_t sector_num, QEMUIOVector *qiov)
+{
+ return bdrv_rwv_co(bs, sector_num, qiov, true);
+}
+
int bdrv_pread(BlockDriverState *bs, int64_t offset,
void *buf, int count1)
{
return count1;
}
-int bdrv_pwrite(BlockDriverState *bs, int64_t offset,
- const void *buf, int count1)
+int bdrv_pwritev(BlockDriverState *bs, int64_t offset, QEMUIOVector *qiov)
{
uint8_t tmp_buf[BDRV_SECTOR_SIZE];
int len, nb_sectors, count;
int64_t sector_num;
int ret;
- count = count1;
+ count = qiov->size;
+
/* first write to align to sector start */
len = (BDRV_SECTOR_SIZE - offset) & (BDRV_SECTOR_SIZE - 1);
if (len > count)
if (len > 0) {
if ((ret = bdrv_read(bs, sector_num, tmp_buf, 1)) < 0)
return ret;
- memcpy(tmp_buf + (offset & (BDRV_SECTOR_SIZE - 1)), buf, len);
+ qemu_iovec_to_buf(qiov, 0, tmp_buf + (offset & (BDRV_SECTOR_SIZE - 1)),
+ len);
if ((ret = bdrv_write(bs, sector_num, tmp_buf, 1)) < 0)
return ret;
count -= len;
if (count == 0)
- return count1;
+ return qiov->size;
sector_num++;
- buf += len;
}
/* write the sectors "in place" */
nb_sectors = count >> BDRV_SECTOR_BITS;
if (nb_sectors > 0) {
- if ((ret = bdrv_write(bs, sector_num, buf, nb_sectors)) < 0)
+ QEMUIOVector qiov_inplace;
+
+ qemu_iovec_init(&qiov_inplace, qiov->niov);
+ qemu_iovec_concat(&qiov_inplace, qiov, len,
+ nb_sectors << BDRV_SECTOR_BITS);
+ ret = bdrv_writev(bs, sector_num, &qiov_inplace);
+ qemu_iovec_destroy(&qiov_inplace);
+ if (ret < 0) {
return ret;
+ }
+
sector_num += nb_sectors;
len = nb_sectors << BDRV_SECTOR_BITS;
- buf += len;
count -= len;
}
if (count > 0) {
if ((ret = bdrv_read(bs, sector_num, tmp_buf, 1)) < 0)
return ret;
- memcpy(tmp_buf, buf, count);
+ qemu_iovec_to_buf(qiov, qiov->size - count, tmp_buf, count);
if ((ret = bdrv_write(bs, sector_num, tmp_buf, 1)) < 0)
return ret;
}
- return count1;
+ return qiov->size;
+}
+
+int bdrv_pwrite(BlockDriverState *bs, int64_t offset,
+ const void *buf, int count1)
+{
+ QEMUIOVector qiov;
+ struct iovec iov = {
+ .iov_base = (void *) buf,
+ .iov_len = count1,
+ };
+
+ qemu_iovec_init_external(&qiov, &iov, 1);
+ return bdrv_pwritev(bs, offset, &qiov);
}
/*
int bdrv_save_vmstate(BlockDriverState *bs, const uint8_t *buf,
int64_t pos, int size)
+{
+ QEMUIOVector qiov;
+ struct iovec iov = {
+ .iov_base = (void *) buf,
+ .iov_len = size,
+ };
+
+ qemu_iovec_init_external(&qiov, &iov, 1);
+ return bdrv_writev_vmstate(bs, &qiov, pos);
+}
+
+int bdrv_writev_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos)
{
BlockDriver *drv = bs->drv;
- if (!drv)
+
+ if (!drv) {
return -ENOMEDIUM;
- if (drv->bdrv_save_vmstate)
- return drv->bdrv_save_vmstate(bs, buf, pos, size);
- if (bs->file)
- return bdrv_save_vmstate(bs->file, buf, pos, size);
+ } else if (drv->bdrv_save_vmstate) {
+ return drv->bdrv_save_vmstate(bs, qiov, pos);
+ } else if (bs->file) {
+ return bdrv_writev_vmstate(bs->file, qiov, pos);
+ }
+
return -ENOTSUP;
}
bool is_write, double elapsed_time, uint64_t *wait)
{
uint64_t bps_limit = 0;
+ uint64_t extension;
double bytes_limit, bytes_base, bytes_res;
double slice_time, wait_time;
* info can be kept until the timer fire, so it is increased and tuned
* based on the result of experiment.
*/
- bs->slice_time = wait_time * BLOCK_IO_SLICE_TIME * 10;
- bs->slice_end += bs->slice_time - 3 * BLOCK_IO_SLICE_TIME;
+ extension = wait_time * NANOSECONDS_PER_SECOND;
+ extension = DIV_ROUND_UP(extension, BLOCK_IO_SLICE_TIME) *
+ BLOCK_IO_SLICE_TIME;
+ bs->slice_end += extension;
if (wait) {
- *wait = wait_time * BLOCK_IO_SLICE_TIME * 10;
+ *wait = wait_time * NANOSECONDS_PER_SECOND;
}
return true;
return false;
}
- /* Calc approx time to dispatch */
+ /* Calc approx time to dispatch, in seconds */
wait_time = (ios_base + 1) / iops_limit;
if (wait_time > elapsed_time) {
wait_time = wait_time - elapsed_time;
wait_time = 0;
}
- bs->slice_time = wait_time * BLOCK_IO_SLICE_TIME * 10;
- bs->slice_end += bs->slice_time - 3 * BLOCK_IO_SLICE_TIME;
+ /* Exceeded current slice, extend it by another slice time */
+ bs->slice_end += BLOCK_IO_SLICE_TIME;
if (wait) {
- *wait = wait_time * BLOCK_IO_SLICE_TIME * 10;
+ *wait = wait_time * NANOSECONDS_PER_SECOND;
}
return true;
int bps_ret, iops_ret;
now = qemu_get_clock_ns(vm_clock);
- if ((bs->slice_start < now)
- && (bs->slice_end > now)) {
- bs->slice_end = now + bs->slice_time;
- } else {
- bs->slice_time = 5 * BLOCK_IO_SLICE_TIME;
+ if (now > bs->slice_end) {
bs->slice_start = now;
- bs->slice_end = now + bs->slice_time;
-
+ bs->slice_end = now + BLOCK_IO_SLICE_TIME;
memset(&bs->slice_submitted, 0, sizeof(bs->slice_submitted));
}
projects / qemu.git / blobdiff