From 7ab32ae64d05f018c171ba1525bc337805d84391 Mon Sep 17 00:00:00 2001
From: Karel Zak <kzak@redhat.com>
Date: Fri, 11 Oct 2013 11:16:23 +0200
Subject: [PATCH] blockdev: add note about --setbsz usability
Signed-off-by: Karel Zak <kzak@redhat.com>
---
disk-utils/blockdev.8 | 4 +++-
disk-utils/blockdev.c | 2 +-
2 files changed, 4 insertions(+), 2 deletions(-)
diff --git a/disk-utils/blockdev.8 b/disk-utils/blockdev.8
index 2b3d64c..f4282da 100644
--- a/disk-utils/blockdev.8
+++ b/disk-utils/blockdev.8
@@ -68,7 +68,9 @@ Get size in 512-byte sectors.
.IP "\fB\-\-rereadpt\fP"
Reread partition table
.IP "\fB\-\-setbsz\fP \fIbytes\fP"
-Set blocksize.
+Set blocksize. Note that the block size is specific to the current file
+descriptor opening the block device, so the change of block size only persists
+for as long as blockdev has the device open, and is lost once blockdev exits.
.IP "\fB\-\-setfra\fP \fIsectors\fP"
Set filesystem readahead (same like --setra on 2.6 kernels).
.IP "\fB\-\-setra\fP \fIsectors\fP"
diff --git a/disk-utils/blockdev.c b/disk-utils/blockdev.c
index 4543818..d030217 100644
--- a/disk-utils/blockdev.c
+++ b/disk-utils/blockdev.c
@@ -127,7 +127,7 @@ static const struct bdc bdcms[] =
.argname = "<bytes>",
.argtype = ARG_INT,
.flags = FL_NORESULT,
- .help = N_("set blocksize")
+ .help = N_("set blocksize on file descriptor opening the block device")
},{
IOCTL_ENTRY(BLKGETSIZE),
.name = "--getsize",
--
1.8.3.1