diff options
Diffstat (limited to 'block.c')
| -rw-r--r-- | block.c | 143 |
1 files changed, 121 insertions, 22 deletions
@@ -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); |