lkml.org 
[lkml]   [2002]   [Aug]   [11]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[PATCH] cdrom sane fallback vs 2.4.20-pre1
Here is an update to cdrom.c.   SCSI-II devices are not required
to support the READ_CD packet command. Currently, the cdrom
driver assumes that _all_ READ_CD packet command failures are due
to READ_CD being unsupported. Obviously, there are a million
other reasons for a READ_CD packet command to fail. Here at my
house, the most common reason for READ_CD failures is that my
kids have, once again, scratched up my CDs resulting in bad
sectors. So the drive hits an uncorrectable error and thinks
that READ_CD is unsupported, and then trys again using READ_10
(which takes another a few seconds to fail and, of course, again
returns an L-EC Uncorrectable Error).

This patch teaches cdrom.c to only fall back to READ_10 when
the drive reports that we sent it an invalid command...

-Erik

--
Erik B. Andersen http://codepoet-consulting.com/
--This message was written using 73% post-consumer electrons--

--- drivers/cdrom/cdrom.c~ Sun Aug 11 15:37:20 2002
+++ drivers/cdrom/cdrom.c Sun Aug 11 15:37:24 2002
@@ -1916,6 +1916,7 @@
{
struct cdrom_device_ops *cdo = cdi->ops;
struct cdrom_generic_command cgc;
+ struct request_sense sense;
kdev_t dev = cdi->dev;
char buffer[32];
int ret = 0;
@@ -1951,9 +1952,11 @@
cgc.buffer = (char *) kmalloc(blocksize, GFP_KERNEL);
if (cgc.buffer == NULL)
return -ENOMEM;
+ memset(&sense, 0, sizeof(sense));
+ cgc.sense = &sense;
cgc.data_direction = CGC_DATA_READ;
ret = cdrom_read_block(cdi, &cgc, lba, 1, format, blocksize);
- if (ret) {
+ if (ret && sense.sense_key==0x05 && sense.asc==0x20 && sense.ascq==0x00) {
/*
* SCSI-II devices are not required to support
* READ_CD, so let's try switching block size
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
\
 
 \ /
  Last update: 2005-03-22 13:27    [W:0.256 / U:1.140 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site