From: Tomohiro Kusumi <tkusumi@tuxera.com>
Date: Mon, 9 Jan 2017 14:42:02 +0000 (+0900)
Subject: Mention sg ioengine requires filename option
X-Git-Tag: fio-2.17~12
X-Git-Url: https://git.kernel.dk/?p=fio.git;a=commitdiff_plain;h=30dac1364aaf86bc6566002d48ea010420b2a9b2

Mention sg ioengine requires filename option

similar to the way net ioengine documents filename option.

Also bring in a file type check from fio_sgio_type_check()
to avoid pointless read capacity error against regfiles.

Signed-off-by: Tomohiro Kusumi <tkusumi@tuxera.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
---

diff --git a/HOWTO b/HOWTO
index 4cc733f6..33f8718a 100644
--- a/HOWTO
+++ b/HOWTO
@@ -819,7 +819,8 @@ ioengine=str	Defines how the job issues io to the file. The following
 				synchronous using the SG_IO ioctl, or if
 				the target is an sg character device
 				we use read(2) and write(2) for asynchronous
-				io.
+				io. Requires filename option to specify either
+				block or character devices.
 
 			null	Doesn't transfer any data, just pretends
 				to. This is mainly used to exercise fio
diff --git a/engines/sg.c b/engines/sg.c
index e70803c8..3f7d9110 100644
--- a/engines/sg.c
+++ b/engines/sg.c
@@ -525,7 +525,7 @@ static int fio_sgio_type_check(struct thread_data *td, struct fio_file *f)
 		}
 	} else {
 		td_verror(td, EINVAL, "wrong file type");
-		log_err("ioengine sg only works on block devices\n");
+		log_err("ioengine sg only works on block or character devices\n");
 		return 1;
 	}
 
@@ -789,6 +789,12 @@ static int fio_sgio_get_file_size(struct thread_data *td, struct fio_file *f)
 	if (fio_file_size_known(f))
 		return 0;
 
+	if (f->filetype != FIO_TYPE_BD && f->filetype != FIO_TYPE_CHAR) {
+		td_verror(td, EINVAL, "wrong file type");
+		log_err("ioengine sg only works on block or character devices\n");
+		return 1;
+	}
+
 	ret = fio_sgio_read_capacity(td, &bs, &max_lba);
 	if (ret ) {
 		td_verror(td, td->error, "fio_sgio_read_capacity");