#include "sysemu/block-backend.h"
#include "block/block_int.h"
#include "block/blockjob.h"
+#include "block/dirty-bitmap.h"
#include "block/qapi.h"
#include "crypto/init.h"
#include "trace/control.h"
" 'output_filename' is the destination disk image filename\n"
" 'output_fmt' is the destination format\n"
" 'options' is a comma separated list of format specific options in a\n"
- " name=value format. Use -o ? for an overview of the options supported by the\n"
- " used format\n"
+ " name=value format. Use -o help for an overview of the options supported by\n"
+ " the used format\n"
" 'snapshot_param' is param used for internal snapshot, format\n"
" is 'snapshot.id=[ID],snapshot.name=[NAME]', or\n"
" '[ID_OR_NAME]'\n"
}
/*
- * Is @optarg safe for accumulate_options()?
+ * Is @list safe for accumulate_options()?
* It is when multiple of them can be joined together separated by ','.
- * To make that work, @optarg must not start with ',' (or else a
+ * To make that work, @list must not start with ',' (or else a
* separating ',' preceding it gets escaped), and it must not end with
* an odd number of ',' (or else a separating ',' following it gets
* escaped), or be empty (or else a separating ',' preceding it can
* escape a separating ',' following it).
*
*/
-static bool is_valid_option_list(const char *optarg)
+static bool is_valid_option_list(const char *list)
{
- size_t len = strlen(optarg);
+ size_t len = strlen(list);
size_t i;
- if (!optarg[0] || optarg[0] == ',') {
+ if (!list[0] || list[0] == ',') {
return false;
}
- for (i = len; i > 0 && optarg[i - 1] == ','; i--) {
+ for (i = len; i > 0 && list[i - 1] == ','; i--) {
}
if ((len - i) % 2) {
return false;
return true;
}
-static int accumulate_options(char **options, char *optarg)
+static int accumulate_options(char **options, char *list)
{
char *new_options;
- if (!is_valid_option_list(optarg)) {
- error_report("Invalid option list: %s", optarg);
+ if (!is_valid_option_list(list)) {
+ error_report("Invalid option list: %s", list);
return -1;
}
if (!*options) {
- *options = g_strdup(optarg);
+ *options = g_strdup(list);
} else {
- new_options = g_strdup_printf("%s,%s", *options, optarg);
+ new_options = g_strdup_printf("%s,%s", *options, list);
g_free(*options);
*options = new_options;
}
blk = img_open_file(filename, NULL, fmt, flags, writethrough, quiet,
force_share);
}
+
+ if (blk) {
+ blk_set_force_allow_inactivate(blk);
+ }
+
return blk;
}
AioContext *aio_context = block_job_get_aio_context(job);
int ret = 0;
- aio_context_acquire(aio_context);
- job_ref(&job->job);
+ job_lock();
+ job_ref_locked(&job->job);
do {
float progress = 0.0f;
+ job_unlock();
aio_poll(aio_context, true);
progress_get_snapshot(&job->job.progress, &progress_current,
progress = (float)progress_current / progress_total * 100.f;
}
qemu_progress_print(progress, 0);
- } while (!job_is_ready(&job->job) && !job_is_completed(&job->job));
+ job_lock();
+ } while (!job_is_ready_locked(&job->job) &&
+ !job_is_completed_locked(&job->job));
- if (!job_is_completed(&job->job)) {
- ret = job_complete_sync(&job->job, errp);
+ if (!job_is_completed_locked(&job->job)) {
+ ret = job_complete_sync_locked(&job->job, errp);
} else {
ret = job->job.ret;
}
- job_unref(&job->job);
- aio_context_release(aio_context);
+ job_unref_locked(&job->job);
+ job_unlock();
/* publish completion progress only when success */
if (!ret) {
done:
qemu_progress_end();
+ /*
+ * Manually inactivate the image first because this way we can know whether
+ * an error occurred. blk_unref() doesn't tell us about failures.
+ */
+ ret = bdrv_inactivate_all();
+ if (ret < 0 && !local_err) {
+ error_setg_errno(&local_err, -ret, "Error while closing the image");
+ }
blk_unref(blk);
if (local_err) {
}
/*
- * Compares two buffers sector by sector. Returns 0 if the first
- * sector of each buffer matches, non-zero otherwise.
+ * Compares two buffers chunk by chunk, where @chsize is the chunk size.
+ * If @chsize is 0, default chunk size of BDRV_SECTOR_SIZE is used.
+ * Returns 0 if the first chunk of each buffer matches, non-zero otherwise.
*
- * pnum is set to the sector-aligned size of the buffer prefix that
- * has the same matching status as the first sector.
+ * @pnum is set to the size of the buffer prefix aligned to @chsize that
+ * has the same matching status as the first chunk.
*/
static int compare_buffers(const uint8_t *buf1, const uint8_t *buf2,
- int64_t bytes, int64_t *pnum)
+ int64_t bytes, uint64_t chsize, int64_t *pnum)
{
bool res;
- int64_t i = MIN(bytes, BDRV_SECTOR_SIZE);
+ int64_t i;
assert(bytes > 0);
+ if (!chsize) {
+ chsize = BDRV_SECTOR_SIZE;
+ }
+ i = MIN(bytes, chsize);
+
res = !!memcmp(buf1, buf2, i);
while (i < bytes) {
- int64_t len = MIN(bytes - i, BDRV_SECTOR_SIZE);
+ int64_t len = MIN(bytes - i, chsize);
if (!!memcmp(buf1 + i, buf2 + i, len) != res) {
break;
ret = 4;
goto out;
}
- ret = compare_buffers(buf1, buf2, chunk, &pnum);
+ ret = compare_buffers(buf1, buf2, chunk, 0, &pnum);
if (ret || pnum != chunk) {
qprintf(quiet, "Content mismatch at offset %" PRId64 "!\n",
offset + (ret ? 0 : pnum));
qemu_co_mutex_unlock(&s->lock);
break;
}
- n = convert_iteration_sectors(s, s->sector_num);
+ WITH_GRAPH_RDLOCK_GUARD() {
+ n = convert_iteration_sectors(s, s->sector_num);
+ }
if (n < 0) {
qemu_co_mutex_unlock(&s->lock);
s->ret = n;
if (s->ret == -EINPROGRESS) {
if (copy_range) {
- ret = convert_co_copy_range(s, sector_num, n);
+ WITH_GRAPH_RDLOCK_GUARD() {
+ ret = convert_co_copy_range(s, sector_num, n);
+ }
if (ret) {
s->copy_range = false;
goto retry;
g_free(sn_tab);
}
-static void dump_json_image_info_list(ImageInfoList *list)
+static void dump_json_block_graph_info_list(BlockGraphInfoList *list)
{
GString *str;
QObject *obj;
Visitor *v = qobject_output_visitor_new(&obj);
- visit_type_ImageInfoList(v, NULL, &list, &error_abort);
+ visit_type_BlockGraphInfoList(v, NULL, &list, &error_abort);
visit_complete(v, &obj);
str = qobject_to_json_pretty(obj, true);
assert(str != NULL);
g_string_free(str, true);
}
-static void dump_json_image_info(ImageInfo *info)
+static void dump_json_block_graph_info(BlockGraphInfo *info)
{
GString *str;
QObject *obj;
Visitor *v = qobject_output_visitor_new(&obj);
- visit_type_ImageInfo(v, NULL, &info, &error_abort);
+ visit_type_BlockGraphInfo(v, NULL, &info, &error_abort);
visit_complete(v, &obj);
str = qobject_to_json_pretty(obj, true);
assert(str != NULL);
g_string_free(str, true);
}
-static void dump_human_image_info_list(ImageInfoList *list)
+static void dump_human_image_info(BlockGraphInfo *info, int indentation,
+ const char *path)
+{
+ BlockChildInfoList *children_list;
+
+ bdrv_node_info_dump(qapi_BlockGraphInfo_base(info), indentation,
+ info->children == NULL);
+
+ for (children_list = info->children; children_list;
+ children_list = children_list->next)
+ {
+ BlockChildInfo *child = children_list->value;
+ g_autofree char *child_path = NULL;
+
+ printf("%*sChild node '%s%s':\n",
+ indentation * 4, "", path, child->name);
+ child_path = g_strdup_printf("%s%s/", path, child->name);
+ dump_human_image_info(child->info, indentation + 1, child_path);
+ }
+}
+
+static void dump_human_image_info_list(BlockGraphInfoList *list)
{
- ImageInfoList *elem;
+ BlockGraphInfoList *elem;
bool delim = false;
for (elem = list; elem; elem = elem->next) {
}
delim = true;
- bdrv_image_info_dump(elem->value);
+ dump_human_image_info(elem->value, 0, "/");
}
}
}
/**
- * Open an image file chain and return an ImageInfoList
+ * Open an image file chain and return an BlockGraphInfoList
*
* @filename: topmost image filename
* @fmt: topmost image format (may be NULL to autodetect)
* @chain: true - enumerate entire backing file chain
* false - only topmost image file
*
- * Returns a list of ImageInfo objects or NULL if there was an error opening an
- * image file. If there was an error a message will have been printed to
- * stderr.
+ * Returns a list of BlockNodeInfo objects or NULL if there was an error
+ * opening an image file. If there was an error a message will have been
+ * printed to stderr.
*/
-static ImageInfoList *collect_image_info_list(bool image_opts,
- const char *filename,
- const char *fmt,
- bool chain, bool force_share)
+static BlockGraphInfoList *collect_image_info_list(bool image_opts,
+ const char *filename,
+ const char *fmt,
+ bool chain, bool force_share)
{
- ImageInfoList *head = NULL;
- ImageInfoList **tail = &head;
+ BlockGraphInfoList *head = NULL;
+ BlockGraphInfoList **tail = &head;
GHashTable *filenames;
Error *err = NULL;
while (filename) {
BlockBackend *blk;
BlockDriverState *bs;
- ImageInfo *info;
+ BlockGraphInfo *info;
if (g_hash_table_lookup_extended(filenames, filename, NULL, NULL)) {
error_report("Backing file '%s' creates an infinite loop.",
}
bs = blk_bs(blk);
- bdrv_query_image_info(bs, &info, &err);
+ /*
+ * Note that the returned BlockGraphInfo object will not have
+ * information about this image's backing node, because we have opened
+ * it with BDRV_O_NO_BACKING. Printing this object will therefore not
+ * duplicate the backing chain information that we obtain by walking
+ * the chain manually here.
+ */
+ bdrv_graph_rdlock_main_loop();
+ bdrv_query_block_graph_info(bs, &info, &err);
+ bdrv_graph_rdunlock_main_loop();
+
if (err) {
error_report_err(err);
blk_unref(blk);
image_opts = false;
if (chain) {
- if (info->has_full_backing_filename) {
+ if (info->full_backing_filename) {
filename = info->full_backing_filename;
- } else if (info->has_backing_filename) {
+ } else if (info->backing_filename) {
error_report("Could not determine absolute backing filename,"
" but backing filename '%s' present",
info->backing_filename);
goto err;
}
- if (info->has_backing_filename_format) {
+ if (info->backing_filename_format) {
fmt = info->backing_filename_format;
}
}
return head;
err:
- qapi_free_ImageInfoList(head);
+ qapi_free_BlockGraphInfoList(head);
g_hash_table_destroy(filenames);
return NULL;
}
OutputFormat output_format = OFORMAT_HUMAN;
bool chain = false;
const char *filename, *fmt, *output;
- ImageInfoList *list;
+ BlockGraphInfoList *list;
bool image_opts = false;
bool force_share = false;
break;
case OFORMAT_JSON:
if (chain) {
- dump_json_image_info_list(list);
+ dump_json_block_graph_info_list(list);
} else {
- dump_json_image_info(list->value);
+ dump_json_block_graph_info(list->value);
}
break;
}
- qapi_free_ImageInfoList(list);
+ qapi_free_BlockGraphInfoList(list);
return 0;
}
printf("%#-16"PRIx64"%#-16"PRIx64"%#-16"PRIx64"%s\n",
e->start, e->length,
e->has_offset ? e->offset : 0,
- e->has_filename ? e->filename : "");
+ e->filename ?: "");
}
/* This format ignores the distinction between 0, ZERO and ZERO|DATA.
* Modify the flags here to allow more coalescing.
case OFORMAT_JSON:
printf("{ \"start\": %"PRId64", \"length\": %"PRId64","
" \"depth\": %"PRId64", \"present\": %s, \"zero\": %s,"
- " \"data\": %s", e->start, e->length, e->depth,
+ " \"data\": %s, \"compressed\": %s",
+ e->start, e->length, e->depth,
e->present ? "true" : "false",
e->zero ? "true" : "false",
- e->data ? "true" : "false");
+ e->data ? "true" : "false",
+ e->compressed ? "true" : "false");
if (e->has_offset) {
printf(", \"offset\": %"PRId64"", e->offset);
}
has_offset = !!(ret & BDRV_BLOCK_OFFSET_VALID);
if (file && has_offset) {
+ bdrv_graph_rdlock_main_loop();
bdrv_refresh_filename(file);
+ bdrv_graph_rdunlock_main_loop();
filename = file->filename;
}
.length = bytes,
.data = !!(ret & BDRV_BLOCK_DATA),
.zero = !!(ret & BDRV_BLOCK_ZERO),
+ .compressed = !!(ret & BDRV_BLOCK_COMPRESSED),
.offset = map,
.has_offset = has_offset,
.depth = depth,
.present = !!(ret & BDRV_BLOCK_ALLOCATED),
- .has_filename = filename,
.filename = filename,
};
}
if (curr->zero != next->zero ||
curr->data != next->data ||
+ curr->compressed != next->compressed ||
curr->depth != next->depth ||
curr->present != next->present ||
- curr->has_filename != next->has_filename ||
+ !curr->filename != !next->filename ||
curr->has_offset != next->has_offset) {
return false;
}
- if (curr->has_filename && strcmp(curr->filename, next->filename)) {
+ if (curr->filename && strcmp(curr->filename, next->filename)) {
return false;
}
if (curr->has_offset && curr->offset + curr->length != next->offset) {
sn.date_sec = rt / G_USEC_PER_SEC;
sn.date_nsec = (rt % G_USEC_PER_SEC) * 1000;
+ bdrv_graph_rdlock_main_loop();
ret = bdrv_snapshot_create(bs, &sn);
+ bdrv_graph_rdunlock_main_loop();
+
if (ret) {
- error_report("Could not create snapshot '%s': %d (%s)",
- snapshot_name, ret, strerror(-ret));
+ error_report("Could not create snapshot '%s': %s",
+ snapshot_name, strerror(-ret));
}
break;
break;
case SNAPSHOT_DELETE:
+ bdrv_graph_rdlock_main_loop();
ret = bdrv_snapshot_find(bs, &sn, snapshot_name);
if (ret < 0) {
error_report("Could not delete snapshot '%s': snapshot not "
ret = 1;
}
}
+ bdrv_graph_rdunlock_main_loop();
break;
}
uint8_t *buf_new = NULL;
BlockDriverState *bs = NULL, *prefix_chain_bs = NULL;
BlockDriverState *unfiltered_bs;
+ BlockDriverInfo bdi = {0};
char *filename;
const char *fmt, *cache, *src_cache, *out_basefmt, *out_baseimg;
int c, flags, src_flags, ret;
+ BdrvRequestFlags write_flags = 0;
bool writethrough, src_writethrough;
int unsafe = 0;
bool force_share = false;
int progress = 0;
bool quiet = false;
+ bool compress = false;
Error *local_err = NULL;
bool image_opts = false;
+ int64_t write_align;
/* Parse commandline parameters */
fmt = NULL;
{"object", required_argument, 0, OPTION_OBJECT},
{"image-opts", no_argument, 0, OPTION_IMAGE_OPTS},
{"force-share", no_argument, 0, 'U'},
+ {"compress", no_argument, 0, 'c'},
{0, 0, 0, 0}
};
- c = getopt_long(argc, argv, ":hf:F:b:upt:T:qU",
+ c = getopt_long(argc, argv, ":hf:F:b:upt:T:qUc",
long_options, NULL);
if (c == -1) {
break;
case 'U':
force_share = true;
break;
+ case 'c':
+ compress = true;
+ break;
}
}
unfiltered_bs = bdrv_skip_filters(bs);
+ if (compress && !block_driver_can_compress(unfiltered_bs->drv)) {
+ error_report("Compression not supported for this file format");
+ ret = -1;
+ goto out;
+ } else if (compress) {
+ write_flags |= BDRV_REQ_WRITE_COMPRESSED;
+ }
+
if (out_basefmt != NULL) {
if (bdrv_find_format(out_basefmt) == NULL) {
error_report("Invalid format name: '%s'", out_basefmt);
}
}
+ /*
+ * We need overlay subcluster size (or cluster size in case writes are
+ * compressed) to make sure write requests are aligned.
+ */
+ ret = bdrv_get_info(unfiltered_bs, &bdi);
+ if (ret < 0) {
+ error_report("could not get block driver info");
+ goto out;
+ } else if (bdi.subcluster_size == 0) {
+ bdi.cluster_size = bdi.subcluster_size = 1;
+ }
+
+ write_align = compress ? bdi.cluster_size : bdi.subcluster_size;
+
/* For safe rebasing we need to compare old and new backing file */
if (!unsafe) {
QDict *options = NULL;
qdict_put_bool(options, BDRV_OPT_FORCE_SHARE, true);
}
+ bdrv_graph_rdlock_main_loop();
bdrv_refresh_filename(bs);
+ bdrv_graph_rdunlock_main_loop();
overlay_filename = bs->exact_filename[0] ? bs->exact_filename
: bs->filename;
out_real_path =
int64_t old_backing_size = 0;
int64_t new_backing_size = 0;
uint64_t offset;
- int64_t n;
+ int64_t n, n_old = 0, n_new = 0;
float local_progress = 0;
- buf_old = blk_blockalign(blk, IO_BUF_SIZE);
- buf_new = blk_blockalign(blk, IO_BUF_SIZE);
+ if (blk_old_backing && bdrv_opt_mem_align(blk_bs(blk_old_backing)) >
+ bdrv_opt_mem_align(blk_bs(blk))) {
+ buf_old = blk_blockalign(blk_old_backing, IO_BUF_SIZE);
+ } else {
+ buf_old = blk_blockalign(blk, IO_BUF_SIZE);
+ }
+ buf_new = blk_blockalign(blk_new_backing, IO_BUF_SIZE);
size = blk_getlength(blk);
if (size < 0) {
}
for (offset = 0; offset < size; offset += n) {
- bool buf_old_is_zero = false;
+ bool old_backing_eof = false;
+ int64_t n_alloc;
/* How many bytes can we handle with the next read? */
n = MIN(IO_BUF_SIZE, size - offset);
}
if (prefix_chain_bs) {
+ uint64_t bytes = n;
+
/*
* If cluster wasn't changed since prefix_chain, we don't need
* to take action
strerror(-ret));
goto out;
}
- if (!ret) {
+ if (!ret && n) {
continue;
}
+ if (!n) {
+ /*
+ * If we've reached EOF of the old backing, it means that
+ * offsets beyond the old backing size were read as zeroes.
+ * Now we will need to explicitly zero the cluster in
+ * order to preserve that state after the rebase.
+ */
+ n = bytes;
+ }
}
+ /*
+ * At this point we know that the region [offset; offset + n)
+ * is unallocated within the target image. This region might be
+ * unaligned to the target image's (sub)cluster boundaries, as
+ * old backing may have smaller clusters (or have subclusters).
+ * We extend it to the aligned boundaries to avoid CoW on
+ * partial writes in blk_pwrite(),
+ */
+ n += offset - QEMU_ALIGN_DOWN(offset, write_align);
+ offset = QEMU_ALIGN_DOWN(offset, write_align);
+ n += QEMU_ALIGN_UP(offset + n, write_align) - (offset + n);
+ n = MIN(n, size - offset);
+ assert(!bdrv_is_allocated(unfiltered_bs, offset, n, &n_alloc) &&
+ n_alloc == n);
+
+ /*
+ * Much like with the target image, we'll try to read as much
+ * of the old and new backings as we can.
+ */
+ n_old = MIN(n, MAX(0, old_backing_size - (int64_t) offset));
+ n_new = MIN(n, MAX(0, new_backing_size - (int64_t) offset));
+
/*
* Read old and new backing file and take into consideration that
* backing files may be smaller than the COW image.
*/
- if (offset >= old_backing_size) {
- memset(buf_old, 0, n);
- buf_old_is_zero = true;
+ memset(buf_old + n_old, 0, n - n_old);
+ if (!n_old) {
+ old_backing_eof = true;
} else {
- if (offset + n > old_backing_size) {
- n = old_backing_size - offset;
- }
-
- ret = blk_pread(blk_old_backing, offset, n, buf_old, 0);
+ ret = blk_pread(blk_old_backing, offset, n_old, buf_old, 0);
if (ret < 0) {
error_report("error while reading from old backing file");
goto out;
}
}
- if (offset >= new_backing_size || !blk_new_backing) {
- memset(buf_new, 0, n);
- } else {
- if (offset + n > new_backing_size) {
- n = new_backing_size - offset;
- }
-
- ret = blk_pread(blk_new_backing, offset, n, buf_new, 0);
+ memset(buf_new + n_new, 0, n - n_new);
+ if (n_new) {
+ ret = blk_pread(blk_new_backing, offset, n_new, buf_new, 0);
if (ret < 0) {
error_report("error while reading from new backing file");
goto out;
int64_t pnum;
if (compare_buffers(buf_old + written, buf_new + written,
- n - written, &pnum))
+ n - written, write_align, &pnum))
{
- if (buf_old_is_zero) {
+ if (old_backing_eof) {
ret = blk_pwrite_zeroes(blk, offset + written, pnum, 0);
} else {
+ assert(written + pnum <= IO_BUF_SIZE);
ret = blk_pwrite(blk, offset + written, pnum,
- buf_old + written, 0);
+ buf_old + written, write_flags);
}
if (ret < 0) {
error_report("Error while writing to COW image: %s",
}
written += pnum;
+ if (offset + written >= old_backing_size) {
+ old_backing_eof = true;
+ }
}
qemu_progress_print(local_progress, 100);
}
{
BlockDriver *drv;
+ GRAPH_RDLOCK_GUARD_MAINLOOP();
+
/* Find driver and parse its options */
drv = bdrv_find_format(format);
if (!drv) {
goto out;
}
+ bdrv_graph_rdlock_main_loop();
if (!bs->drv->bdrv_amend_options) {
error_report("Format driver '%s' does not support option amendment",
fmt);
+ bdrv_graph_rdunlock_main_loop();
ret = -1;
goto out;
}
"This option is only supported for image creation\n");
}
+ bdrv_graph_rdunlock_main_loop();
error_report_err(err);
ret = -1;
goto out;
qemu_progress_print(0.f, 0);
ret = bdrv_amend_options(bs, opts, &amend_status_cb, NULL, force, &err);
qemu_progress_print(100.f, 0);
+ bdrv_graph_rdunlock_main_loop();
+
if (ret < 0) {
error_report_err(err);
goto out;
struct timeval t1, t2;
int i;
bool force_share = false;
- size_t buf_size;
+ size_t buf_size = 0;
for (;;) {
static const struct option long_options[] = {
data.buf = blk_blockalign(blk, buf_size);
memset(data.buf, pattern, data.nrreq * data.bufsize);
- blk_register_buf(blk, data.buf, buf_size);
+ blk_register_buf(blk, data.buf, buf_size, &error_fatal);
data.qiov = g_new(QEMUIOVector, data.nrreq);
for (i = 0; i < data.nrreq; i++) {
out:
if (data.buf) {
- blk_unregister_buf(blk, data.buf);
+ blk_unregister_buf(blk, data.buf, buf_size);
}
qemu_vfree(data.buf);
blk_unref(blk);
QSIMPLEQ_HEAD(, ImgBitmapAction) actions;
ImgBitmapAction *act, *act_next;
const char *op;
+ int inactivate_ret;
QSIMPLEQ_INIT(&actions);
ret = 0;
out:
+ /*
+ * Manually inactivate the images first because this way we can know whether
+ * an error occurred. blk_unref() doesn't tell us about failures.
+ */
+ inactivate_ret = bdrv_inactivate_all();
+ if (inactivate_ret < 0) {
+ error_report("Error while closing the image: %s", strerror(-inactivate_ret));
+ ret = 1;
+ }
+
blk_unref(src);
blk_unref(blk);
qemu_opts_del(opts);
const char *out_fmt = "raw";
const char *fmt = NULL;
int64_t size = 0;
- int64_t block_count = 0, out_pos, in_pos;
+ int64_t out_pos, in_pos;
bool force_share = false;
struct DdInfo dd = {
.flags = 0,
in.buf = g_new(uint8_t, in.bsz);
- for (out_pos = 0; in_pos < size; block_count++) {
+ for (out_pos = 0; in_pos < size; ) {
int bytes = (in_pos + in.bsz > size) ? size - in_pos : in.bsz;
ret = blk_pread(blk1, in_pos, bytes, in.buf, 0);