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-rw-r--r--block.c143
1 files changed, 121 insertions, 22 deletions
diff --git a/block.c b/block.c
index 0a062c9..16a92a4 100644
--- a/block.c
+++ b/block.c
@@ -676,7 +676,7 @@ static int bdrv_open_common(BlockDriverState *bs, BlockDriverState *file,
assert(drv != NULL);
assert(bs->file == NULL);
- assert(options == NULL || bs->options != options);
+ assert(options != NULL && bs->options != options);
trace_bdrv_open_common(bs, filename, flags, drv->format_name);
@@ -688,7 +688,11 @@ static int bdrv_open_common(BlockDriverState *bs, BlockDriverState *file,
bdrv_enable_copy_on_read(bs);
}
- pstrcpy(bs->filename, sizeof(bs->filename), filename);
+ if (filename != NULL) {
+ pstrcpy(bs->filename, sizeof(bs->filename), filename);
+ } else {
+ bs->filename[0] = '\0';
+ }
if (use_bdrv_whitelist && !bdrv_is_whitelisted(drv)) {
return -ENOTSUP;
@@ -708,7 +712,8 @@ static int bdrv_open_common(BlockDriverState *bs, BlockDriverState *file,
bdrv_swap(file, bs);
ret = 0;
} else {
- ret = drv->bdrv_file_open(bs, filename, open_flags);
+ assert(drv->bdrv_parse_filename || filename != NULL);
+ ret = drv->bdrv_file_open(bs, filename, options, open_flags);
}
} else {
assert(file != NULL);
@@ -727,6 +732,7 @@ static int bdrv_open_common(BlockDriverState *bs, BlockDriverState *file,
#ifndef _WIN32
if (bs->is_temporary) {
+ assert(filename != NULL);
unlink(filename);
}
#endif
@@ -742,27 +748,92 @@ free_and_fail:
/*
* Opens a file using a protocol (file, host_device, nbd, ...)
+ *
+ * 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 belongs to the block layer
+ * after the call (even on failure), so if the caller intends to reuse the
+ * dictionary, it needs to use QINCREF() before calling bdrv_file_open.
*/
-int bdrv_file_open(BlockDriverState **pbs, const char *filename, int flags)
+int bdrv_file_open(BlockDriverState **pbs, const char *filename,
+ QDict *options, int flags)
{
BlockDriverState *bs;
BlockDriver *drv;
+ const char *drvname;
int ret;
- drv = bdrv_find_protocol(filename);
- if (!drv) {
- return -ENOENT;
+ /* NULL means an empty set of options */
+ if (options == NULL) {
+ options = qdict_new();
}
bs = bdrv_new("");
- ret = bdrv_open_common(bs, NULL, filename, NULL, flags, drv);
+ bs->options = options;
+ options = qdict_clone_shallow(options);
+
+ /* Find the right block driver */
+ drvname = qdict_get_try_str(options, "driver");
+ if (drvname) {
+ drv = bdrv_find_whitelisted_format(drvname);
+ qdict_del(options, "driver");
+ } else if (filename) {
+ drv = bdrv_find_protocol(filename);
+ } else {
+ qerror_report(ERROR_CLASS_GENERIC_ERROR,
+ "Must specify either driver or file");
+ drv = NULL;
+ }
+
+ if (!drv) {
+ ret = -ENOENT;
+ goto fail;
+ }
+
+ /* Parse the filename and open it */
+ if (drv->bdrv_parse_filename && filename) {
+ Error *local_err = NULL;
+ drv->bdrv_parse_filename(filename, options, &local_err);
+ if (error_is_set(&local_err)) {
+ qerror_report_err(local_err);
+ error_free(local_err);
+ ret = -EINVAL;
+ goto fail;
+ }
+ } else if (!drv->bdrv_parse_filename && !filename) {
+ qerror_report(ERROR_CLASS_GENERIC_ERROR,
+ "The '%s' block driver requires a file name",
+ drv->format_name);
+ ret = -EINVAL;
+ goto fail;
+ }
+
+ ret = bdrv_open_common(bs, NULL, filename, options, flags, drv);
if (ret < 0) {
- bdrv_delete(bs);
- return ret;
+ goto fail;
}
+
+ /* Check if any unknown options were used */
+ if (qdict_size(options) != 0) {
+ const QDictEntry *entry = qdict_first(options);
+ qerror_report(ERROR_CLASS_GENERIC_ERROR, "Block protocol '%s' doesn't "
+ "support the option '%s'",
+ drv->format_name, entry->key);
+ ret = -EINVAL;
+ goto fail;
+ }
+ QDECREF(options);
+
bs->growable = 1;
*pbs = bs;
return 0;
+
+fail:
+ QDECREF(options);
+ if (!bs->drv) {
+ QDECREF(bs->options);
+ }
+ bdrv_delete(bs);
+ return ret;
}
int bdrv_open_backing_file(BlockDriverState *bs)
@@ -802,6 +873,25 @@ int bdrv_open_backing_file(BlockDriverState *bs)
return 0;
}
+static void extract_subqdict(QDict *src, QDict **dst, const char *start)
+{
+ const QDictEntry *entry, *next;
+ const char *p;
+
+ *dst = qdict_new();
+ entry = qdict_first(src);
+
+ while (entry != NULL) {
+ next = qdict_next(src, entry);
+ if (strstart(entry->key, start, &p)) {
+ qobject_incref(entry->value);
+ qdict_put_obj(*dst, p, entry->value);
+ qdict_del(src, entry->key);
+ }
+ entry = next;
+ }
+}
+
/*
* Opens a disk image (raw, qcow2, vmdk, ...)
*
@@ -817,6 +907,7 @@ int bdrv_open(BlockDriverState *bs, const char *filename, QDict *options,
/* TODO: extra byte is a hack to ensure MAX_PATH space on Windows. */
char tmp_filename[PATH_MAX + 1];
BlockDriverState *file = NULL;
+ QDict *file_options = NULL;
/* NULL means an empty set of options */
if (options == NULL) {
@@ -831,9 +922,16 @@ int bdrv_open(BlockDriverState *bs, const char *filename, QDict *options,
BlockDriverState *bs1;
int64_t total_size;
BlockDriver *bdrv_qcow2;
- QEMUOptionParameter *options;
+ QEMUOptionParameter *create_options;
char backing_filename[PATH_MAX];
+ if (qdict_size(options) != 0) {
+ error_report("Can't use snapshot=on with driver-specific options");
+ ret = -EINVAL;
+ goto fail;
+ }
+ assert(filename != NULL);
+
/* if snapshot, we create a temporary backing file and open it
instead of opening 'filename' directly */
@@ -863,17 +961,19 @@ int bdrv_open(BlockDriverState *bs, const char *filename, QDict *options,
}
bdrv_qcow2 = bdrv_find_format("qcow2");
- options = parse_option_parameters("", bdrv_qcow2->create_options, NULL);
+ create_options = parse_option_parameters("", bdrv_qcow2->create_options,
+ NULL);
- set_option_parameter_int(options, BLOCK_OPT_SIZE, total_size);
- set_option_parameter(options, BLOCK_OPT_BACKING_FILE, backing_filename);
+ set_option_parameter_int(create_options, BLOCK_OPT_SIZE, total_size);
+ set_option_parameter(create_options, BLOCK_OPT_BACKING_FILE,
+ backing_filename);
if (drv) {
- set_option_parameter(options, BLOCK_OPT_BACKING_FMT,
+ set_option_parameter(create_options, BLOCK_OPT_BACKING_FMT,
drv->format_name);
}
- ret = bdrv_create(bdrv_qcow2, tmp_filename, options);
- free_option_parameters(options);
+ ret = bdrv_create(bdrv_qcow2, tmp_filename, create_options);
+ free_option_parameters(create_options);
if (ret < 0) {
goto fail;
}
@@ -888,7 +988,10 @@ int bdrv_open(BlockDriverState *bs, const char *filename, QDict *options,
flags |= BDRV_O_ALLOW_RDWR;
}
- ret = bdrv_file_open(&file, filename, bdrv_open_flags(bs, flags));
+ extract_subqdict(options, &file_options, "file.");
+
+ ret = bdrv_file_open(&file, filename, file_options,
+ bdrv_open_flags(bs, flags));
if (ret < 0) {
goto fail;
}
@@ -2487,10 +2590,6 @@ int bdrv_truncate(BlockDriverState *bs, int64_t offset)
return -EACCES;
if (bdrv_in_use(bs))
return -EBUSY;
-
- /* There better not be any in-flight IOs when we truncate the device. */
- bdrv_drain_all();
-
ret = drv->bdrv_truncate(bs, offset);
if (ret == 0) {
ret = refresh_total_sectors(bs, offset >> BDRV_SECTOR_BITS);
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