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Diffstat (limited to 'qemu-io.c')
-rw-r--r--qemu-io.c192
1 files changed, 192 insertions, 0 deletions
diff --git a/qemu-io.c b/qemu-io.c
index f39109e..72a4524 100644
--- a/qemu-io.c
+++ b/qemu-io.c
@@ -267,6 +267,47 @@ static int do_aio_writev(QEMUIOVector *qiov, int64_t offset, int *total)
return async_ret < 0 ? async_ret : 1;
}
+struct multiwrite_async_ret {
+ int num_done;
+ int error;
+};
+
+static void multiwrite_cb(void *opaque, int ret)
+{
+ struct multiwrite_async_ret *async_ret = opaque;
+
+ async_ret->num_done++;
+ if (ret < 0) {
+ async_ret->error = ret;
+ }
+}
+
+static int do_aio_multiwrite(BlockRequest* reqs, int num_reqs, int *total)
+{
+ int i, ret;
+ struct multiwrite_async_ret async_ret = {
+ .num_done = 0,
+ .error = 0,
+ };
+
+ *total = 0;
+ for (i = 0; i < num_reqs; i++) {
+ reqs[i].cb = multiwrite_cb;
+ reqs[i].opaque = &async_ret;
+ *total += reqs[i].qiov->size;
+ }
+
+ ret = bdrv_aio_multiwrite(bs, reqs, num_reqs);
+ if (ret < 0) {
+ return ret;
+ }
+
+ while (async_ret.num_done < num_reqs) {
+ qemu_aio_wait();
+ }
+
+ return async_ret.error < 0 ? async_ret.error : 1;
+}
static void
read_help(void)
@@ -811,6 +852,156 @@ out:
return 0;
}
+static void
+multiwrite_help(void)
+{
+ printf(
+"\n"
+" writes a range of bytes from the given offset source from multiple buffers,\n"
+" in a batch of requests that may be merged by qemu\n"
+"\n"
+" Example:\n"
+" 'multiwrite 512 1k 1k ; 4k 1k' \n"
+" writes 2 kB at 512 bytes and 1 kB at 4 kB into the open file\n"
+"\n"
+" Writes into a segment of the currently open file, using a buffer\n"
+" filled with a set pattern (0xcdcdcdcd). The pattern byte is increased\n"
+" by one for each request contained in the multiwrite command.\n"
+" -P, -- use different pattern to fill file\n"
+" -C, -- report statistics in a machine parsable format\n"
+" -q, -- quiet mode, do not show I/O statistics\n"
+"\n");
+}
+
+static int multiwrite_f(int argc, char **argv);
+
+static const cmdinfo_t multiwrite_cmd = {
+ .name = "multiwrite",
+ .cfunc = multiwrite_f,
+ .argmin = 2,
+ .argmax = -1,
+ .args = "[-Cq] [-P pattern ] off len [len..] [; off len [len..]..]",
+ .oneline = "issues multiple write requests at once",
+ .help = multiwrite_help,
+};
+
+static int
+multiwrite_f(int argc, char **argv)
+{
+ struct timeval t1, t2;
+ int Cflag = 0, qflag = 0;
+ int c, cnt;
+ char **buf;
+ int64_t offset, first_offset = 0;
+ /* Some compilers get confused and warn if this is not initialized. */
+ int total = 0;
+ int nr_iov;
+ int nr_reqs;
+ int pattern = 0xcd;
+ QEMUIOVector *qiovs;
+ int i;
+ BlockRequest *reqs;
+
+ while ((c = getopt(argc, argv, "CqP:")) != EOF) {
+ switch (c) {
+ case 'C':
+ Cflag = 1;
+ break;
+ case 'q':
+ qflag = 1;
+ break;
+ case 'P':
+ pattern = parse_pattern(optarg);
+ if (pattern < 0)
+ return 0;
+ break;
+ default:
+ return command_usage(&writev_cmd);
+ }
+ }
+
+ if (optind > argc - 2)
+ return command_usage(&writev_cmd);
+
+ nr_reqs = 1;
+ for (i = optind; i < argc; i++) {
+ if (!strcmp(argv[i], ";")) {
+ nr_reqs++;
+ }
+ }
+
+ reqs = qemu_malloc(nr_reqs * sizeof(*reqs));
+ buf = qemu_malloc(nr_reqs * sizeof(*buf));
+ qiovs = qemu_malloc(nr_reqs * sizeof(*qiovs));
+
+ for (i = 0; i < nr_reqs; i++) {
+ int j;
+
+ /* Read the offset of the request */
+ offset = cvtnum(argv[optind]);
+ if (offset < 0) {
+ printf("non-numeric offset argument -- %s\n", argv[optind]);
+ return 0;
+ }
+ optind++;
+
+ if (offset & 0x1ff) {
+ printf("offset %lld is not sector aligned\n",
+ (long long)offset);
+ return 0;
+ }
+
+ if (i == 0) {
+ first_offset = offset;
+ }
+
+ /* Read lengths for qiov entries */
+ for (j = optind; j < argc; j++) {
+ if (!strcmp(argv[j], ";")) {
+ break;
+ }
+ }
+
+ nr_iov = j - optind;
+
+ /* Build request */
+ reqs[i].qiov = &qiovs[i];
+ buf[i] = create_iovec(reqs[i].qiov, &argv[optind], nr_iov, pattern);
+ reqs[i].sector = offset >> 9;
+ reqs[i].nb_sectors = reqs[i].qiov->size >> 9;
+
+ optind = j + 1;
+
+ offset += reqs[i].qiov->size;
+ pattern++;
+ }
+
+ gettimeofday(&t1, NULL);
+ cnt = do_aio_multiwrite(reqs, nr_reqs, &total);
+ gettimeofday(&t2, NULL);
+
+ if (cnt < 0) {
+ printf("aio_multiwrite failed: %s\n", strerror(-cnt));
+ goto out;
+ }
+
+ if (qflag)
+ goto out;
+
+ /* Finally, report back -- -C gives a parsable format */
+ t2 = tsub(t2, t1);
+ print_report("wrote", &t2, first_offset, total, total, cnt, Cflag);
+out:
+ for (i = 0; i < nr_reqs; i++) {
+ qemu_io_free(buf[i]);
+ qemu_iovec_destroy(&qiovs[i]);
+ }
+ qemu_free(buf);
+ qemu_free(reqs);
+ qemu_free(qiovs);
+ return 0;
+}
+
struct aio_ctx {
QEMUIOVector qiov;
int64_t offset;
@@ -1483,6 +1674,7 @@ int main(int argc, char **argv)
add_command(&readv_cmd);
add_command(&write_cmd);
add_command(&writev_cmd);
+ add_command(&multiwrite_cmd);
add_command(&aio_read_cmd);
add_command(&aio_write_cmd);
add_command(&aio_flush_cmd);