@@ -1229,11 +1229,22 @@ static int raw_create(const char *filename, QEMUOptionParameter *options,
int fd;
int result = 0;
int64_t total_size = 0;
+ PreallocMode prealloc = PREALLOC_MODE_OFF;
/* Read out options */
while (options && options->name) {
if (!strcmp(options->name, BLOCK_OPT_SIZE)) {
total_size = options->value.n & BDRV_SECTOR_MASK;
+ } else if (!strcmp(options->name, BLOCK_OPT_PREALLOC)) {
+ if (!options->value.s || !strcmp(options->value.s, "off")) {
+ prealloc = PREALLOC_MODE_OFF;
+ } else if (!strcmp(options->value.s, "full")) {
+ prealloc = PREALLOC_MODE_FULL;
+ } else {
+ error_setg(errp, "Invalid preallocation mode: '%s'",
+ options->value.s);
+ return -EINVAL;
+ }
}
options++;
}
@@ -1243,16 +1254,27 @@ static int raw_create(const char *filename, QEMUOptionParameter *options,
if (fd < 0) {
result = -errno;
error_setg_errno(errp, -result, "Could not create file");
- } else {
- if (ftruncate(fd, total_size) != 0) {
- result = -errno;
- error_setg_errno(errp, -result, "Could not resize file");
- }
- if (qemu_close(fd) != 0) {
- result = -errno;
- error_setg_errno(errp, -result, "Could not close the new file");
+ goto out;
+ }
+ if (ftruncate(fd, total_size) != 0) {
+ result = -errno;
+ error_setg_errno(errp, -result, "Could not resize file");
+ goto out_close;
+ }
+ if (prealloc == PREALLOC_MODE_FULL) {
+ /* posix_fallocate() doesn't set errno. */
+ result = -posix_fallocate(fd, 0, total_size);
+ if (result != 0) {
+ error_setg_errno(errp, -result,
+ "Could not preallocate data for the new file");
}
}
+out_close:
+ if (qemu_close(fd) != 0) {
+ result = -errno;
+ error_setg_errno(errp, -result, "Could not close the new file");
+ }
+out:
return result;
}
@@ -1403,6 +1425,11 @@ static QEMUOptionParameter raw_create_options[] = {
.type = OPT_SIZE,
.help = "Virtual disk size"
},
+ {
+ .name = BLOCK_OPT_PREALLOC,
+ .type = OPT_STRING,
+ .help = "Preallocation mode (allowed values: off, full)"
+ },
{ NULL }
};