From: Chip Coldwell <coldwell@redhat.com>
Subject: [RHEL5.1 PATCH] bz248728 PCI shutdown for cciss driver
Date: Fri, 3 Aug 2007 19:25:01 -0400 (EDT)
Bugzilla: 248728
Message-Id: <Pine.LNX.4.64.0708031923011.26752@bogart.boston.redhat.com>
Changelog: [scsi] PCI shutdown for cciss driver



This is a late critical bug fix for the cciss driver submitted by Mike
Miller of HP.  Basically, we need a shutdown callback to flush the
battery-backed cache in the adapter.  The bz has all apropriate flags
set, the patch was submitted upstream by MM, and compile-tested by me.

The patch adds support for the pci shutdown method. This is required to
ensure we flush the battery backed write cache. This patch is included
in 2.6.22.1. This is a critical fix. Without this patch it is possible to
leave data in the BBWC on reboot or shutdown. Potential for data loss. This
patch has been tested with up to 512 logical volumes.
Please include this patch.

Signed-off-by: Mike Miller <mike.miller@hp.com>

-------------------------------------------------------------------------------
 cciss.c |   65
++++++++++++++++++++++++++++++++++++++++++----------------------
 1 file changed, 43 insertions(+), 22 deletions(-)

diff -burNp linux-2.6.18.i386-p0001/drivers/block/cciss.c linux-2.6.18.i386/drivers/block/cciss.c
--- linux-2.6.18.i386-p0001/drivers/block/cciss.c	2007-07-16 10:59:12.000000000 -0500
+++ linux-2.6.18.i386/drivers/block/cciss.c	2007-07-16 12:39:10.000000000 -0500
@@ -167,6 +167,7 @@ static int sendcmd_withirq(__u8 cmd, int
 			   __u8 page_code, int cmd_type);
 
 static void fail_all_cmds(unsigned long ctlr);
+static void cciss_shutdown(struct pci_dev *);
 
 #ifdef CONFIG_PROC_FS
 static int cciss_proc_get_info(char *buffer, char **start, off_t offset,
@@ -3393,47 +3394,53 @@ static int __devinit cciss_init_one(stru
 	return -1;
 }
 
-static void __devexit cciss_remove_one(struct pci_dev *pdev)
+static void cciss_shutdown(struct pci_dev *pdev)
 {
 	ctlr_info_t *tmp_ptr;
-	int i, j;
+	int i;
 	char flush_buf[4];
 	int return_code;
 
-	if (pci_get_drvdata(pdev) == NULL) {
-		printk(KERN_ERR "cciss: Unable to remove device \n");
-		return;
-	}
 	tmp_ptr = pci_get_drvdata(pdev);
+	if (tmp_ptr == NULL)
+		return;
 	i = tmp_ptr->ctlr;
-	if (hba[i] == NULL) {
-		printk(KERN_ERR "cciss: device appears to "
-		       "already be removed \n");
+	if (hba[i] == NULL)
 		return;
-	}
+
 	/* Turn board interrupts off  and send the flush cache command */
 	/* sendcmd will turn off interrupt, and send the flush...
 	 * To write all data in the battery backed cache to disks */
 	memset(flush_buf, 0, 4);
 	return_code = sendcmd(CCISS_CACHE_FLUSH, i, flush_buf, 4, 0, 0, 0, NULL,
 			      TYPE_CMD);
-	if (return_code != IO_OK) {
-		printk(KERN_WARNING "Error Flushing cache on controller %d\n",
-		       i);
+	if (return_code == IO_OK) {
+		printk(KERN_INFO "Completed flushing cache on controller %d\n", i);
+	} else {
+		printk(KERN_WARNING "Error flushing cache on controller %d\n", i);
 	}
 	free_irq(hba[i]->intr[2], hba[i]);
+}
 
-#ifdef CONFIG_PCI_MSI
-	if (hba[i]->msix_vector)
-		pci_disable_msix(hba[i]->pdev);
-	else if (hba[i]->msi_vector)
-		pci_disable_msi(hba[i]->pdev);
-#endif				/* CONFIG_PCI_MSI */
+static void __devexit cciss_remove_one(struct pci_dev *pdev)
+{
+	ctlr_info_t *tmp_ptr;
+	int i, j;
+
+	if (pci_get_drvdata(pdev) == NULL) {
+		printk(KERN_ERR "cciss: Unable to remove device \n");
+		return;
+	}
+	tmp_ptr = pci_get_drvdata(pdev);
+	i = tmp_ptr->ctlr;
+	if (hba[i] == NULL) {
+		printk(KERN_ERR "cciss: device appears to "
+		       "already be removed \n");
+		return;
+	}
 
-	iounmap(hba[i]->vaddr);
-	cciss_unregister_scsi(i);	/* unhook from SCSI subsystem */
-	unregister_blkdev(hba[i]->major, hba[i]->devname);
 	remove_proc_entry(hba[i]->devname, proc_cciss);
+	unregister_blkdev(hba[i]->major, hba[i]->devname);
 
 	/* remove it from the disk list */
 	for (j = 0; j < CISS_MAX_LUN; j++) {
@@ -3448,6 +3455,19 @@ static void __devexit cciss_remove_one(s
 		}
 	}
 
+	cciss_unregister_scsi(i);	/* unhook from SCSI subsystem */
+
+	cciss_shutdown(pdev);
+
+#ifdef CONFIG_PCI_MSI
+	if (hba[i]->msix_vector)
+		pci_disable_msix(hba[i]->pdev);
+	else if (hba[i]->msi_vector)
+		pci_disable_msi(hba[i]->pdev);
+#endif				/* CONFIG_PCI_MSI */
+
+	iounmap(hba[i]->vaddr);
+
 	pci_free_consistent(hba[i]->pdev, hba[i]->nr_cmds * sizeof(CommandList_struct),
 			    hba[i]->cmd_pool, hba[i]->cmd_pool_dhandle);
 	pci_free_consistent(hba[i]->pdev, hba[i]->nr_cmds * sizeof(ErrorInfo_struct),
@@ -3470,6 +3490,7 @@ static struct pci_driver cciss_pci_drive
 	.probe = cciss_init_one,
 	.remove = __devexit_p(cciss_remove_one),
 	.id_table = cciss_pci_device_id,	/* id_table */
+	.shutdown = cciss_shutdown,
 };
 
 /*


-- 
Charles M. "Chip" Coldwell
Senior Software Engineer
Red Hat, Inc
978-392-2426