From: Stephen M. Cameron <[email protected]>
This attribute, requested by Redhat, allows kexec-tools to know
whether the controller can honor the reset_devices kernel parameter
and actually reset the controller. For kdump to work properly it
is necessary that the reset_devices parameter be honored. This
attribute enables kexec-tools to warn the user if they attempt to
designate a non-resettable controller as the dump device.
Signed-off-by: Stephen M. Cameron <[email protected]>
---
.../ABI/testing/sysfs-bus-pci-devices-cciss | 12 ++++++
drivers/block/cciss.c | 39 ++++++++++++++++++++
2 files changed, 51 insertions(+), 0 deletions(-)
diff --git a/Documentation/ABI/testing/sysfs-bus-pci-devices-cciss b/Documentation/ABI/testing/sysfs-bus-pci-devices-cciss
index 4f29e5f..f5bb0a3 100644
--- a/Documentation/ABI/testing/sysfs-bus-pci-devices-cciss
+++ b/Documentation/ABI/testing/sysfs-bus-pci-devices-cciss
@@ -59,3 +59,15 @@ Kernel Version: 2.6.31
Contact: [email protected]
Description: Displays the usage count (number of opens) of logical drive Y
of controller X.
+
+Where: /sys/bus/pci/devices/<dev>/ccissX/resettable
+Date: February 2011
+Kernel Version: 2.6.38
+Contact: [email protected]
+Description: Value of 1 indicates the controller can honor the reset_devices
+ kernel parameter. Value of 0 indicates reset_devices cannot be
+ honored. This is to allow, for example, kexec tools to be able
+ to warn the user if they designate an unresettable device as
+ a dump device, as kdump requires resetting the device in order
+ to work reliably.
+
diff --git a/drivers/block/cciss.c b/drivers/block/cciss.c
index 8e52e63..f6a9fdb 100644
--- a/drivers/block/cciss.c
+++ b/drivers/block/cciss.c
@@ -560,6 +560,44 @@ static void __devinit cciss_procinit(ctlr_info_t *h)
#define to_hba(n) container_of(n, struct ctlr_info, dev)
#define to_drv(n) container_of(n, drive_info_struct, dev)
+/* List of controllers which cannot be reset on kexec with reset_devices */
+static u32 unresettable_controller[] = {
+ 0x324a103C, /* Smart Array P712m */
+ 0x324b103C, /* SmartArray P711m */
+ 0x3223103C, /* Smart Array P800 */
+ 0x3234103C, /* Smart Array P400 */
+ 0x3235103C, /* Smart Array P400i */
+ 0x3211103C, /* Smart Array E200i */
+ 0x3212103C, /* Smart Array E200 */
+ 0x3213103C, /* Smart Array E200i */
+ 0x3214103C, /* Smart Array E200i */
+ 0x3215103C, /* Smart Array E200i */
+ 0x3237103C, /* Smart Array E500 */
+ 0x323D103C, /* Smart Array P700m */
+ 0x409C0E11, /* Smart Array 6400 */
+ 0x409D0E11, /* Smart Array 6400 EM */
+};
+
+static int ctlr_is_resettable(struct ctlr_info *h)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(unresettable_controller); i++)
+ if (unresettable_controller[i] == h->board_id)
+ return 0;
+ return 1;
+}
+
+static ssize_t host_show_resettable(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct ctlr_info *h = to_hba(dev);
+
+ return snprintf(buf, 20, "%d\n", ctlr_is_resettable(h));
+}
+static DEVICE_ATTR(resettable, S_IRUGO, host_show_resettable, NULL);
+
static ssize_t host_store_rescan(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
@@ -745,6 +783,7 @@ static DEVICE_ATTR(usage_count, S_IRUGO, cciss_show_usage_count, NULL);
static struct attribute *cciss_host_attrs[] = {
&dev_attr_rescan.attr,
+ &dev_attr_resettable.attr,
NULL
};
On 2011-03-10 21:23, Stephen M. Cameron wrote:
> From: Stephen M. Cameron <[email protected]>
>
> This attribute, requested by Redhat, allows kexec-tools to know
> whether the controller can honor the reset_devices kernel parameter
> and actually reset the controller. For kdump to work properly it
> is necessary that the reset_devices parameter be honored. This
> attribute enables kexec-tools to warn the user if they attempt to
> designate a non-resettable controller as the dump device.
Applied.
--
Jens Axboe