dataplacement: update ruh info initialization

The current way of initilization limits ruhs from 0 to 127.
Although fio supports a maximum of 128 ruhs, for the files supporting
more the 128 placement ids user has the flexibility of specifying any
128 placement id index at a time. This commit updates the way we fetch
ruhs. We now fetch the ruhs info in two steps. The first step only gets
us the number of ruhs from the ioengine. This is used by fdp backend to
allocate the correct buffer size for the second step, where we fetch
the actual ruhs info.

Signed-off-by: Ankit Kumar <[email protected]>

dataplacement.c

@@ -43,18 +43,19 @@ static int fdp_ruh_info(struct thread_data *td, struct fio_file *f,
 static int init_ruh_info(struct thread_data *td, struct fio_file *f)
 {
 	struct fio_ruhs_info *ruhs, *tmp;
+	uint32_t nr_ruhs;
 	int i, ret;
 
-	ruhs = scalloc(1, sizeof(*ruhs) + FDP_MAX_RUHS * sizeof(*ruhs->plis));
-	if (!ruhs)
-		return -ENOMEM;
-
 	/* set up the data structure used for FDP to work with the supplied stream IDs */
 	if (td->o.dp_type == FIO_DP_STREAMS) {
 		if (!td->o.dp_nr_ids) {
 			log_err("fio: stream IDs must be provided for dataplacement=streams\n");
 			return -EINVAL;
 		}
+		ruhs = scalloc(1, sizeof(*ruhs) + FDP_MAX_RUHS * sizeof(*ruhs->plis));
+		if (!ruhs)
+			return -ENOMEM;
+
 		ruhs->nr_ruhs = td->o.dp_nr_ids;
 		for (int i = 0; i < ruhs->nr_ruhs; i++)
 			ruhs->plis[i] = td->o.dp_ids[i];
@@ -63,26 +64,50 @@ static int init_ruh_info(struct thread_data *td, struct fio_file *f)
 		return 0;
 	}
 
+	/*
+	 * Since we don't know the actual number of ruhs. Only fetch the header.
+	 * We will reallocate this buffer and then fetch all the ruhs again.
+	 */
+	ruhs = calloc(1, sizeof(*ruhs));
 	ret = fdp_ruh_info(td, f, ruhs);
 	if (ret) {
 		log_info("fio: ruh info failed for %s (%d)\n",
 			 f->file_name, -ret);
 		goto out;
 	}
 
-	if (ruhs->nr_ruhs > FDP_MAX_RUHS)
-		ruhs->nr_ruhs = FDP_MAX_RUHS;
+	nr_ruhs = ruhs->nr_ruhs;
+	ruhs = realloc(ruhs, sizeof(*ruhs) + nr_ruhs * sizeof(*ruhs->plis));
+	if (!ruhs) {
+		log_info("fio: ruhs buffer realloc failed for %s\n",
+			 f->file_name);
+		ret = -ENOMEM;
+		goto out;
+	}
 
-	if (td->o.dp_nr_ids == 0) {
-		f->ruhs_info = ruhs;
-		return 0;
+	ruhs->nr_ruhs = nr_ruhs;
+	ret = fdp_ruh_info(td, f, ruhs);
+	if (ret) {
+		log_info("fio: ruh info failed for %s (%d)\n",
+			 f->file_name, -ret);
+		goto out;
 	}
 
-	for (i = 0; i < td->o.dp_nr_ids; i++) {
-		if (td->o.dp_ids[i] >= ruhs->nr_ruhs) {
+	if (td->o.dp_nr_ids == 0) {
+		if (ruhs->nr_ruhs > FDP_MAX_RUHS)
+			ruhs->nr_ruhs = FDP_MAX_RUHS;
+	} else {
+		if (td->o.dp_nr_ids > FDP_MAX_RUHS) {
 			ret = -EINVAL;
 			goto out;
 		}
+		for (i = 0; i < td->o.dp_nr_ids; i++) {
+			if (td->o.dp_ids[i] >= ruhs->nr_ruhs) {
+				ret = -EINVAL;
+				goto out;
+			}
+		}
+		ruhs->nr_ruhs = td->o.dp_nr_ids;
 	}
 
 	tmp = scalloc(1, sizeof(*tmp) + ruhs->nr_ruhs * sizeof(*tmp->plis));
@@ -91,12 +116,23 @@ static int init_ruh_info(struct thread_data *td, struct fio_file *f)
 		goto out;
 	}
 
+	if (td->o.dp_nr_ids == 0) {
+		for (i = 0; i < ruhs->nr_ruhs; i++)
+			tmp->plis[i] = ruhs->plis[i];
+
+		tmp->nr_ruhs = ruhs->nr_ruhs;
+		f->ruhs_info = tmp;
+		free(ruhs);
+
+		return 0;
+	}
+
 	tmp->nr_ruhs = td->o.dp_nr_ids;
 	for (i = 0; i < td->o.dp_nr_ids; i++)
 		tmp->plis[i] = ruhs->plis[td->o.dp_ids[i]];
 	f->ruhs_info = tmp;
 out:
-	sfree(ruhs);
+	free(ruhs);
 	return ret;
 }