[SCSI] hpsa: export resettable host attribute

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 <scameron@beardog.cce.hp.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
This commit is contained in:
Stephen M. Cameron 2011-03-09 17:00:06 -06:00 committed by James Bottomley
parent 3f5eac3a04
commit 941b1cdae8
2 changed files with 53 additions and 0 deletions

View File

@ -45,6 +45,7 @@ HPSA specific entries in /sys
/sys/class/scsi_host/host*/rescan
/sys/class/scsi_host/host*/firmware_revision
/sys/class/scsi_host/host*/resettable
/sys/class/scsi_host/host*/transport_mode
the host "rescan" attribute is a write only attribute. Writing to this
@ -66,6 +67,17 @@ HPSA specific entries in /sys
or "simple" mode. This is controlled by the "hpsa_simple_mode" module
parameter.
The "resettable" read-only attribute indicates whether a particular
controller is able to honor the "reset_devices" kernel parameter. If the
device is resettable, this file will contain a "1", otherwise, a "0". This
parameter is used by kdump, for example, to reset the controller at driver
load time to eliminate any outstanding commands on the controller and get the
controller into a known state so that the kdump initiated i/o will work right
and not be disrupted in any way by stale commands or other stale state
remaining on the controller from the previous kernel. This attribute enables
kexec tools to warn the user if they attempt to designate a device which is
unable to honor the reset_devices kernel parameter as a dump device.
HPSA specific disk attributes:
------------------------------

View File

@ -273,6 +273,44 @@ static ssize_t host_show_transport_mode(struct device *dev,
"performant" : "simple");
}
/* 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;
struct Scsi_Host *shost = class_to_shost(dev);
h = shost_to_hba(shost);
return snprintf(buf, 20, "%d\n", ctlr_is_resettable(h));
}
static inline int is_logical_dev_addr_mode(unsigned char scsi3addr[])
{
return (scsi3addr[3] & 0xC0) == 0x40;
@ -379,6 +417,8 @@ static DEVICE_ATTR(commands_outstanding, S_IRUGO,
host_show_commands_outstanding, NULL);
static DEVICE_ATTR(transport_mode, S_IRUGO,
host_show_transport_mode, NULL);
static DEVICE_ATTR(resettable, S_IRUGO,
host_show_resettable, NULL);
static struct device_attribute *hpsa_sdev_attrs[] = {
&dev_attr_raid_level,
@ -392,6 +432,7 @@ static struct device_attribute *hpsa_shost_attrs[] = {
&dev_attr_firmware_revision,
&dev_attr_commands_outstanding,
&dev_attr_transport_mode,
&dev_attr_resettable,
NULL,
};