Merge branch 'for-3.10/drivers' of git://git.kernel.dk/linux-block

[mirror_ubuntu-artful-kernel.git] / drivers / block / cciss.c

diff --git a/drivers/block/cciss.c b/drivers/block/cciss.c
index 94b51c5e0678b0abf9c0b077e532158b7518378f..6374dc103521f451863cb988cc68921448eb2ae1 100644 (file)
--- a/drivers/block/cciss.c
+++ b/drivers/block/cciss.c
@@ -75,6 +75,12 @@ module_param(cciss_simple_mode, int, S_IRUGO|S_IWUSR);
 MODULE_PARM_DESC(cciss_simple_mode,
        "Use 'simple mode' rather than 'performant mode'");
 
+static int cciss_allow_hpsa;
+module_param(cciss_allow_hpsa, int, S_IRUGO|S_IWUSR);
+MODULE_PARM_DESC(cciss_allow_hpsa,
+       "Prevent cciss driver from accessing hardware known to be "
+       " supported by the hpsa driver");
+
 static DEFINE_MUTEX(cciss_mutex);
 static struct proc_dir_entry *proc_cciss;
 
@@ -4115,9 +4121,13 @@ static int cciss_lookup_board_id(struct pci_dev *pdev, u32 *board_id)
        *board_id = ((subsystem_device_id << 16) & 0xffff0000) |
                        subsystem_vendor_id;
 
-       for (i = 0; i < ARRAY_SIZE(products); i++)
+       for (i = 0; i < ARRAY_SIZE(products); i++) {
+               /* Stand aside for hpsa driver on request */
+               if (cciss_allow_hpsa)
+                       return -ENODEV;
                if (*board_id == products[i].board_id)
                        return i;
+       }
        dev_warn(&pdev->dev, "unrecognized board ID: 0x%08x, ignoring.\n",
                *board_id);
        return -ENODEV;
@@ -4959,6 +4969,16 @@ static int cciss_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
        ctlr_info_t *h;
        unsigned long flags;
 
+       /*
+        * By default the cciss driver is used for all older HP Smart Array
+        * controllers. There are module paramaters that allow a user to
+        * override this behavior and instead use the hpsa SCSI driver. If
+        * this is the case cciss may be loaded first from the kdump initrd
+        * image and cause a kernel panic. So if reset_devices is true and
+        * cciss_allow_hpsa is set just bail.
+        */
+       if ((reset_devices) && (cciss_allow_hpsa == 1))
+               return -ENODEV;
        rc = cciss_init_reset_devices(pdev);
        if (rc) {
                if (rc != -ENOTSUPP)