Initial blktrace support
This doesn't work yet, just committing what little bits I did as not
to lose them.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/blktrace.c b/blktrace.c
new file mode 100644
index 0000000..178a2a3
--- /dev/null
+++ b/blktrace.c
@@ -0,0 +1,95 @@
+/*
+ * blktrace support code for fio
+ */
+#include <stdio.h>
+#include <stdlib.h>
+#include "list.h"
+#include "fio.h"
+#include "blktrace_api.h"
+
+static int discard_pdu(int fd, struct blk_io_trace *t)
+{
+ if (t->pdu_len == 0)
+ return 0;
+
+ if (lseek(fd, t->pdu_len, SEEK_CUR) < 0)
+ return errno;
+
+ return 0;
+}
+
+int is_blktrace(const char *filename)
+{
+ struct blk_io_trace t;
+ int fd, ret;
+
+ fd = open(filename, O_RDONLY);
+ if (fd < 0) {
+ perror("open blktrace");
+ return 0;
+ }
+
+ ret = read(fd, &t, sizeof(t));
+ close(fd);
+
+ if (ret < 0) {
+ perror("read blktrace");
+ return 0;
+ } else if (ret != sizeof(t)) {
+ log_err("fio: short read on blktrace file\n");
+ return 0;
+ }
+
+ if ((t.magic & 0xffffff00) == BLK_IO_TRACE_MAGIC)
+ return 1;
+
+ return 0;
+}
+
+static void handle_trace(struct thread_data *td, struct blk_io_trace *t)
+{
+}
+
+int load_blktrace(struct thread_data *td, const char *filename)
+{
+ struct blk_io_trace t;
+ int fd;
+
+ fd = open(filename, O_RDONLY);
+ if (fd < 0) {
+ td_verror(td, errno, "open blktrace file");
+ return 1;
+ }
+
+ do {
+ int ret = read(fd, &t, sizeof(t));
+
+ if (ret < 0) {
+ td_verror(td, errno, "read blktrace file");
+ return 1;
+ } else if (!ret) {
+ break;
+ } else if (ret != sizeof(t)) {
+ log_err("fio: short read on blktrace file\n");
+ return 1;
+ }
+
+ if ((t.magic & 0xffffff00) != BLK_IO_TRACE_MAGIC) {
+ log_err("fio: bad magic in blktrace data\n");
+ return 1;
+ }
+ if ((t.magic & 0xff) != BLK_IO_TRACE_VERSION) {
+ log_err("fio: bad blktrace version %d\n", t.magic & 0xff);
+ return 1;
+ }
+ ret = discard_pdu(fd, &t);
+ if (ret) {
+ td_verror(td, ret, "blktrace lseek");
+ return 1;
+ }
+ handle_trace(td, &t);
+ } while (1);
+
+ close(fd);
+ return 0;
+}