[ANNOUNCE] megaraid 2.00.6 patch for kernels without hostlock

[ANNOUNCE] megaraid 2.00.6 patch for kernels without hostlock

[Bagalkote, Sreenivas]

Please apply this patch to megaraid 2.00.6 driver for kernels that don't
support per host lock. This can be found at :

ftp://ftp.lsil.com/pub/linux-megaraid/drivers/version-2.00.6/

Sreenivas Bagalkote
LSI Logic

--- megaraid_2006/megaraid2.c	2003-07-30 14:43:36.000000000 -0400
+++ megaraid_2006_wo_hostlock/megaraid2.c	2003-07-30
15:05:35.000000000 -0400
@@ -394,7 +394,6 @@
 
 		adapter->flag = flag;
 		spin_lock_init(&adapter->lock);
-		host->lock = &adapter->lock;
 
 		host->cmd_per_lun = max_cmd_per_lun;
 		host->max_sectors = max_sectors_per_io;
@@ -1775,7 +1774,7 @@
 	unsigned long	flags;
 
 
-	spin_lock_irqsave(&adapter->lock, flags);
+	spin_lock_irqsave(&io_request_lock, flags);
 
 	megaraid_iombox_ack_sequence(adapter);
 
@@ -1784,7 +1783,7 @@
 		mega_runpendq(adapter);
 	}
 
-	spin_unlock_irqrestore(&adapter->lock, flags);
+	spin_unlock_irqrestore(&io_request_lock, flags);
 
 	return;
 }
@@ -1857,7 +1856,7 @@
 	unsigned long	flags;
 
 
-	spin_lock_irqsave(&adapter->lock, flags);
+	spin_lock_irqsave(&io_request_lock, flags);
 
 	megaraid_memmbox_ack_sequence(adapter);
 
@@ -1866,7 +1865,7 @@
 		mega_runpendq(adapter);
 	}
 
-	spin_unlock_irqrestore(&adapter->lock, flags);
+	spin_unlock_irqrestore(&io_request_lock, flags);
 
 	return;
 }
@@ -2618,7 +2617,7 @@
 
 	adapter = (adapter_t *)scp->host->hostdata;
 
-	ASSERT( spin_is_locked(&adapter->lock) );
+	ASSERT( spin_is_locked(&io_request_lock) );
 
 	printk("megaraid: aborting-%ld cmd=%x <c=%d t=%d l=%d>\n",
 		scp->serial_number, scp->cmnd[0], scp->channel, scp->target,
@@ -2715,7 +2714,7 @@
 
 	adapter = (adapter_t *)cmd->host->hostdata;
 
-	ASSERT( spin_is_locked(&adapter->lock) );
+	ASSERT( spin_is_locked(&io_request_lock) );
 
 	printk("megaraid: reset-%ld cmd=%x <c=%d t=%d l=%d>\n",
 		cmd->serial_number, cmd->cmnd[0], cmd->channel, cmd->target,
@@ -2726,7 +2725,7 @@
 	mc.cmd = MEGA_CLUSTER_CMD;
 	mc.opcode = MEGA_RESET_RESERVATIONS;
 
-	spin_unlock_irq(&adapter->lock);
+	spin_unlock_irq(&io_request_lock);
 	if( mega_internal_command(adapter, LOCK_INT, &mc, NULL) != 0 ) {
 		printk(KERN_WARNING
 				"megaraid: reservation reset failed.\n");
@@ -2734,7 +2733,7 @@
 	else {
 		printk(KERN_INFO "megaraid: reservation reset.\n");
 	}
-	spin_lock_irq(&adapter->lock);
+	spin_lock_irq(&io_request_lock);
 #endif
 
 	/*
@@ -4958,7 +4957,7 @@
 	scb_t *scb;
 	int rval;
 
-	ASSERT( !spin_is_locked(&adapter->lock) );
+	ASSERT( !spin_is_locked(&io_request_lock) );
 
 	/*
 	 * Stop sending commands to the controller, queue them internally.
@@ -4978,7 +4977,7 @@
 	rval = mega_do_del_logdrv(adapter, logdrv);
 
 
-	spin_lock_irqsave(&adapter->lock, flags);
+	spin_lock_irqsave(&io_request_lock, flags);
 
 	/*
 	 * If delete operation was successful, add 0x80 to the logical drive
@@ -4997,7 +4996,7 @@
 
 	mega_runpendq(adapter);
 
-	spin_unlock_irqrestore(&adapter->lock, flags);
+	spin_unlock_irqrestore(&io_request_lock, flags);
 
 	return rval;
 }
@@ -5547,11 +5546,11 @@
 	/*
 	 * Get the lock only if the caller has not acquired it already
 	 */
-	if( ls == LOCK_INT ) spin_lock_irqsave(&adapter->lock, flags);
+	if( ls == LOCK_INT ) spin_lock_irqsave(&io_request_lock, flags);
 
 	megaraid_queue(scmd, mega_internal_done);
 
-	if( ls == LOCK_INT ) spin_unlock_irqrestore(&adapter->lock, flags);
+	if( ls == LOCK_INT ) spin_unlock_irqrestore(&io_request_lock,
flags);
 
 	/*
 	 * Wait till this command finishes. Do not use

Re: [ANNOUNCE] megaraid 2.00.6 patch for kernels without hostlock

[Jens Axboe]

On Wed, Jul 30 2003, Bagalkote, Sreenivas wrote:
> Please apply this patch to megaraid 2.00.6 driver for kernels that don't
> support per host lock. This can be found at :
> 
> ftp://ftp.lsil.com/pub/linux-megaraid/drivers/version-2.00.6/

It's easily possible to keep the impact of maintaining a driver across
such kernels a lot smaller, by simply using the same lock in the
spin_lock calls and just assign that lock to adapter->lock or
io_request_lock depending on the kernel.

-- 
Jens Axboe

Re: [ANNOUNCE] megaraid 2.00.6 patch for kernels without hostlock

[Jens Axboe]

On Thu, Jul 31 2003, Mukker, Atul wrote:
> 
> Well, that's definitely a good idea. Expect a new driver with this change.
> BTW, is there a kernel version beyond which all versions would support per
> host lock, and I mean a 2.4.x kernel :-)

Unfortunately no, however it is trivial to just add host->lock pointer
and make it point to io_request_lock. Ditto for q->queue_lock. That wont
change how the code operates at all. I will probably do that once 2.4.23
opens, it would make maintaining 2.6/2.4 drivers much easier (and ditto
for vendor kernels).

-- 
Jens Axboe

Re: [ANNOUNCE] megaraid 2.00.6 patch for kernels without hostlock

[Matthew Wilcox]

On Thu, Jul 31, 2003 at 05:10:50PM -0400, Mukker, Atul wrote:
> 
> Well, that's definitely a good idea. Expect a new driver with this change.
> BTW, is there a kernel version beyond which all versions would support per
> host lock, and I mean a 2.4.x kernel :-)

that's a pretty dangerous change to make to a stable kernel.  much better
to work on stabilising 2.6.

-- 
"It's not Hollywood.  War is real, war is primarily not about defeat or
victory, it is about death.  I've seen thousands and thousands of dead bodies.
Do you think I want to have an academic debate on this subject?" -- Robert Fisk

RE: [ANNOUNCE] megaraid 2.00.6 patch for kernels without hostlock

[Mukker, Atul]

Well, that's definitely a good idea. Expect a new driver with this change.
BTW, is there a kernel version beyond which all versions would support per
host lock, and I mean a 2.4.x kernel :-)

Thanks
-Atul Mukker

> -----Original Message-----
> From: Jens Axboe [mailto:axboe@suse.de]
> Sent: Thursday, July 31, 2003 5:06 AM
> To: Bagalkote, Sreenivas
> Cc: 'linux-kernel@vger.kernel.org'; 'linux-scsi@vger.kernel.org';
> 'linux-megaraid-devel@dell.com'
> Subject: Re: [ANNOUNCE] megaraid 2.00.6 patch for kernels without
> hostlock
> 
> 
> On Wed, Jul 30 2003, Bagalkote, Sreenivas wrote:
> > Please apply this patch to megaraid 2.00.6 driver for 
> kernels that don't
> > support per host lock. This can be found at :
> > 
> > ftp://ftp.lsil.com/pub/linux-megaraid/drivers/version-2.00.6/
> 
> It's easily possible to keep the impact of maintaining a driver across
> such kernels a lot smaller, by simply using the same lock in the
> spin_lock calls and just assign that lock to adapter->lock or
> io_request_lock depending on the kernel.
> 
> -- 
> Jens Axboe
> 
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