From: Mikael Pettersson <mikpe@csd.uu.se>
To: linux-kernel@vger.kernel.org
Cc: alan@lxorguk.ukuu.org.uk, ionut@cs.columbia.edu
Subject: [PATCH,RFC] make ide-scsi more selective
Date: Wed, 22 Aug 2001 21:46:03 +0200 (MET DST) [thread overview]
Message-ID: <200108221946.VAA01879@harpo.it.uu.se> (raw)
On Mon, 20 Aug 2001 12:28:27 -0400 (EDT), Ion Badulescu wrote:
>The current IDE code doesn't allow the user to reserve a drive to be used
>only with ide-scsi emulation, if the ide-scsi layer is compiled as a
>module.
I've been rather annoyed by a dual problem in the ide-scsi setup:
during initialisation, ide-scsi will claim ALL currently unassigned
IDE devices. This is a problem in modular setups, since there's
no guarantee that currently unassigned devices actually are intended
for ide-scsi.
In my case ide-scsi would often steal my ATAPI tape drive since
my ide-tape module usually isn't loaded. Since I don't want this
to happen (for both practical and aesthetic reasons) I've used a
hack in my /etc/modules.conf to forcibly load ide-tape before
scsi_mod, but this is extremely ugly.
Seeing Ion's comment I decided to do something about this, so I
implemented a "units=" module parameter for ide-scsi, which causes
ide-scsi to skip units not explicitly listed. For symmetry one can
also specify this with a "idescsi=" kernel boot parameter.
Caveat: When listing multiple units, don't use "," to separate their
names (e.g. units=hdc,hdd). modutils insists that "," separates array
elements but the actual MODULE_PARM is a single string. I'd use "+"
instead (e.g. units=hdc+hdd), except I actually want to restrict
ide-scsi to a single unit, so I pass "units=hdc" to it.
The patch below implements this option for 2.4.8-ac9. I've also put
it in http://www.csd.uu.se/~mikpe/linux/idescsi/ together with patches
for 2.2.20pre9 with and without Andre's big IDE patch.
Comments?
/Mikael
--- linux-2.4.8-ac9/drivers/ide/ide.c.~1~ Wed Aug 22 14:13:03 2001
+++ linux-2.4.8-ac9/drivers/ide/ide.c Wed Aug 22 14:20:56 2001
@@ -3006,6 +3006,9 @@
if (strncmp(s,"hd",2) == 0 && s[2] == '=') /* hd= is for hd.c */
return 0; /* driver and not us */
+ if (!strncmp(s, "idescsi=", 8)) /* for ide-scsi.c not us */
+ return 0;
+
if (strncmp(s,"ide",3) &&
strncmp(s,"idebus",6) &&
strncmp(s,"hd",2)) /* hdx= & hdxlun= */
--- linux-2.4.8-ac9/drivers/scsi/ide-scsi.c.~1~ Thu Feb 22 15:23:46 2001
+++ linux-2.4.8-ac9/drivers/scsi/ide-scsi.c Wed Aug 22 14:20:56 2001
@@ -561,6 +561,19 @@
NULL
};
+static char *units;
+#ifdef MODULE
+MODULE_PARM(units, "s");
+#else
+/* the name "idescsi_setup" has already been taken :-( */
+static int __init setup_idescsi(char *s)
+{
+ units = s;
+ return 1;
+}
+__setup("idescsi=", setup_idescsi);
+#endif
+
/*
* idescsi_init will register the driver for each scsi.
*/
@@ -580,7 +593,8 @@
for (i = 0; media[i] != 255; i++) {
failed = 0;
while ((drive = ide_scan_devices (media[i], idescsi_driver.name, NULL, failed++)) != NULL) {
-
+ if (units && !strstr(units, drive->name))
+ continue;
if ((scsi = (idescsi_scsi_t *) kmalloc (sizeof (idescsi_scsi_t), GFP_KERNEL)) == NULL) {
printk (KERN_ERR "ide-scsi: %s: Can't allocate a scsi structure\n", drive->name);
continue;
next reply other threads:[~2001-08-22 19:47 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2001-08-22 19:46 Mikael Pettersson [this message]
2001-08-23 2:49 ` [PATCH,RFC] make ide-scsi more selective Keith Owens
[not found] <no.id>
2001-08-22 21:17 ` Alan Cox
2001-08-22 21:53 ` Nicholas Knight
2001-08-22 22:00 ` Ion Badulescu
2001-08-22 22:39 ` Nicholas Knight
2001-08-23 3:42 ` mhobgood
2001-08-23 3:54 ` Ion Badulescu
2001-08-23 4:29 ` Nicholas Knight
2001-08-23 0:12 ` Willem Riede
2001-08-25 6:56 ` Ion Badulescu
2001-08-22 22:37 Torrey Hoffman
2001-08-22 23:51 Chris Rankin
2001-08-25 12:10 Mikael Pettersson
2001-08-25 12:37 ` André Dahlqvist
2001-08-25 17:33 ` safemode
[not found] <200108251734.NAA28426@cs.columbia.edu>
2001-08-27 14:37 ` Ion Badulescu
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=200108221946.VAA01879@harpo.it.uu.se \
--to=mikpe@csd.uu.se \
--cc=alan@lxorguk.ukuu.org.uk \
--cc=ionut@cs.columbia.edu \
--cc=linux-kernel@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).