[patch 1/1] drivers/scsi: fix proc_scsi_write to return "length" on success with remove-single-device case

[patch 1/1] drivers/scsi: fix proc_scsi_write to return "length" on success with remove-single-device case

[akpm]

From: Suzuki <suzuki@in.ibm.com>

proc_scsi_write doesn't return the "length" upon successfully removing a
device; instead it returns 0.  This causes commands like "echo" to redo the
write(), which ends up in something like,

$ echo "scsi remove-single-device 0 0 3 0" > /proc/scsi/scsi
"-bash: echo: write error: No such device or address"

, even though the device was removed.

Signed-off-by: Suzuki K P <suzuki@in.ibm.com>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
---

 drivers/scsi/scsi_proc.c |    2 ++
 1 files changed, 2 insertions(+)

diff -puN drivers/scsi/scsi_proc.c~drivers-scsi-fix-proc_scsi_write-to-return-length-on drivers/scsi/scsi_proc.c
--- 25/drivers/scsi/scsi_proc.c~drivers-scsi-fix-proc_scsi_write-to-return-length-on	Wed Apr 26 14:39:48 2006
+++ 25-akpm/drivers/scsi/scsi_proc.c	Wed Apr 26 14:39:48 2006
@@ -282,6 +282,8 @@ static ssize_t proc_scsi_write(struct fi
 		lun = simple_strtoul(p + 1, &p, 0);
 
 		err = scsi_remove_single_device(host, channel, id, lun);
+		if (!err)
+			err = length;
 	}
 
  out:
_

Re: [patch 1/1] drivers/scsi: fix proc_scsi_write to return "length" on success with remove-single-device case

[James Bottomley]

On Wed, 2006-04-26 at 14:41 -0700, akpm@osdl.org wrote:
> +               if (!err)
> +                       err = length;

We have more than one of these cases; we might as well accommodate them
all at the bottom of the routine, like the attached

James

diff --git a/drivers/scsi/scsi_proc.c b/drivers/scsi/scsi_proc.c
index 07be62b..55200e4 100644
--- a/drivers/scsi/scsi_proc.c
+++ b/drivers/scsi/scsi_proc.c
@@ -266,8 +266,6 @@ static ssize_t proc_scsi_write(struct fi
 		lun = simple_strtoul(p + 1, &p, 0);
 
 		err = scsi_add_single_device(host, channel, id, lun);
-		if (err >= 0)
-			err = length;
 
 	/*
 	 * Usage: echo "scsi remove-single-device 0 1 2 3" >/proc/scsi/scsi
@@ -284,6 +282,13 @@ static ssize_t proc_scsi_write(struct fi
 		err = scsi_remove_single_device(host, channel, id, lun);
 	}
 
+	/*
+	 * convert success returns so that we return the 
+	 * number of bytes consumed.
+	 */
+	if (!err)
+		err = length;
+
  out:
 	free_page((unsigned long)buffer);
 	return err;