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Message-Id: <1181274015.3275.25.camel@bluegenie>
Date: Fri, 08 Jun 2007 09:10:15 +0530
From: Surya <surya.prabhakar@...ro.com>
To: jesper.juhl@...il.com, emoenke <emoenke@...g.de>
Cc: linux-kernel@...r.kernel.org,
kernel-janitors <kernel-janitors@...ts.osdl.org>
Subject: Re: [PATCH]: complete cleanup of check_region]
re-sending with a minor correction...
<snip>
> >
> > @@ -5640,6 +5645,7 @@ int __init sbpcd_init(void)
> > int i=0, j=0;
> > int addr[2]={1, CDROM_PORT};
> > int port_index;
> > + int request_region_flag;
> >
> One could argue that it would be possible to just use the 'j' variable
> for this since it's not used for anything else until the *_region()
> stuff is all done, that would save adding a new variable...
completely eliminated the variable, haven't felt the need for it.
<snip>
> > msg(DBG_INI,"check_drives done.\n");
> > + if(request_region_flag==0)
> > + release_region(addr[1],4);
>
> I know the driver in its current version just tests if the region is
> available and doesn't hang on to it, but I'm wondering if that's not a
> bug. Shouldn't we actually hold on to this region as long as the
> driver is loaded and only release the region in the sbpcd_exit()
> function, just loke we do with the "CDo_command" region?
But if any of the conditions fail after the request_region code, it is
returning an error and exiting out of init. Dont we need to cleanup
request_region's allocation before we exit. Infact I had a feeling that
CDo_command region cleanup was not perfect. Did a cleanup of both the
regions wherever we have a return out of the function.
Please have a look at the below patch.
diff --git a/drivers/cdrom/sbpcd.c b/drivers/cdrom/sbpcd.c
index a1283b1..5078211 100644
--- a/drivers/cdrom/sbpcd.c
+++ b/drivers/cdrom/sbpcd.c
@@ -358,6 +358,10 @@
* Add bio/kdev_t changes for 2.5.x required to make it work again.
* Still room for improvement in the request handling here if anyone
* actually cares. Bring your own chainsaw. Paul G. 02/2002
+ *
+ *
+ * Cleaned up the reference for deprecated check_region to
+ * request_region. - Surya Prabhakar N 08/07/2007
*/
@@ -555,6 +559,8 @@ static struct cdrom_read_audio read_audio;
static unsigned char msgnum;
static char msgbuf[80];
+static int addr[2]={1, CDROM_PORT};
+
static int max_drives = MAX_DRIVES;
module_param(max_drives, int, 0);
#ifndef MODULE
@@ -5638,7 +5644,6 @@ int __init sbpcd_init(void)
#endif
{
int i=0, j=0;
- int addr[2]={1, CDROM_PORT};
int port_index;
sti();
@@ -5670,9 +5675,9 @@ int __init sbpcd_init(void)
{
addr[1]=sbpcd[port_index];
if (addr[1]==0) break;
- if (check_region(addr[1],4))
+ if (!request_region(addr[1],4, "sbpcd driver"))
{
- msg(DBG_INF,"check_region: %03X is not free.\n",addr[1]);
+ msg(DBG_INF,"request_region: %03X is not free.\n",addr[1]);
continue;
}
if (sbpcd[port_index+1]==2) type=str_sp;
@@ -5699,6 +5704,7 @@ int __init sbpcd_init(void)
if (ndrives==0)
{
msg(DBG_INF, "No drive found.\n");
+ release_region(addr[1],4);
#ifdef MODULE
return -EIO;
#else
@@ -5775,6 +5781,7 @@ int __init sbpcd_init(void)
if (!request_region(CDo_command,4,major_name))
{
printk(KERN_WARNING "sbpcd: Unable to request region 0x%x\n", CDo_command);
+ release_region(addr[1],4);
return -EIO;
}
@@ -5788,6 +5795,8 @@ int __init sbpcd_init(void)
#endif /* SOUND_BASE */
if (register_blkdev(MAJOR_NR, major_name)) {
+ release_region(CDo_command,4);
+ release_region(addr[1],4);
#ifdef MODULE
return -EIO;
#else
@@ -5801,6 +5810,7 @@ int __init sbpcd_init(void)
sbpcd_queue = blk_init_queue(do_sbpcd_request, &sbpcd_lock);
if (!sbpcd_queue) {
release_region(CDo_command,4);
+ release_region(addr[1],4);
unregister_blkdev(MAJOR_NR, major_name);
return -ENOMEM;
}
@@ -5834,6 +5844,7 @@ int __init sbpcd_init(void)
printk("Can't unregister %s\n", major_name);
}
release_region(CDo_command,4);
+ release_region(addr[1],4);
blk_cleanup_queue(sbpcd_queue);
return -EIO;
}
@@ -5850,6 +5861,7 @@ int __init sbpcd_init(void)
if (sbpcd_infop == NULL)
{
release_region(CDo_command,4);
+ release_region(addr[1],4);
blk_cleanup_queue(sbpcd_queue);
return -ENOMEM;
}
@@ -5894,6 +5906,7 @@ static void sbpcd_exit(void)
return;
}
release_region(CDo_command,4);
+ release_region(addr[1],4);
blk_cleanup_queue(sbpcd_queue);
for (j=0;j<NR_SBPCD;j++)
{
-surya.
-
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