[PATCH 10/10] hpsa: update device attributes when they change

From: Stephen M. Cameron
Date: Thu Jan 19 2012 - 15:01:33 EST


From: Scott Teel <scott.teel@xxxxxx>

Certain types of changes to devices should not be interpreted as a device
change that would cause the device to be removed and re-added. These include
RAID level and Firmware revision changes. However, these attribute changes DO
need to be reflected in the controller info structure's dev structure list, so
that sysfs and /proc info files for the devices will reflect the new values.

Signed-off-by: Scott Teel <scott.stacy.teel@xxxxxx>
Acked-by: Stephen M. Cameron <scameron@xxxxxxxxxxxxxxxxxx>
---
drivers/scsi/hpsa.c | 43 ++++++++++++++++++++++++++++++++++++++++---
1 files changed, 40 insertions(+), 3 deletions(-)

diff --git a/drivers/scsi/hpsa.c b/drivers/scsi/hpsa.c
index bf75e4c..56a4e8a 100644
--- a/drivers/scsi/hpsa.c
+++ b/drivers/scsi/hpsa.c
@@ -675,6 +675,20 @@ lun_assigned:
return 0;
}

+/* Update an entry in h->dev[] array. */
+static void hpsa_scsi_update_entry(struct ctlr_info *h, int hostno,
+ int entry, struct hpsa_scsi_dev_t *new_entry)
+{
+ /* assumes h->devlock is held */
+ BUG_ON(entry < 0 || entry >= HPSA_MAX_DEVICES);
+
+ /* Raid level changed. */
+ h->dev[entry]->raid_level = new_entry->raid_level;
+ dev_info(&h->pdev->dev, "%s device c%db%dt%dl%d updated.\n",
+ scsi_device_type(new_entry->devtype), hostno, new_entry->bus,
+ new_entry->target, new_entry->lun);
+}
+
/* Replace an entry from h->dev[] array. */
static void hpsa_scsi_replace_entry(struct ctlr_info *h, int hostno,
int entry, struct hpsa_scsi_dev_t *new_entry,
@@ -781,10 +795,25 @@ static inline int device_is_the_same(struct hpsa_scsi_dev_t *dev1,
return 1;
}

+static inline int device_updated(struct hpsa_scsi_dev_t *dev1,
+ struct hpsa_scsi_dev_t *dev2)
+{
+ /* Device attributes that can change, but don't mean
+ * that the device is a different device, nor that the OS
+ * needs to be told anything about the change.
+ */
+ if (dev1->raid_level != dev2->raid_level)
+ return 1;
+ return 0;
+}
+
/* Find needle in haystack. If exact match found, return DEVICE_SAME,
* and return needle location in *index. If scsi3addr matches, but not
* vendor, model, serial num, etc. return DEVICE_CHANGED, and return needle
- * location in *index. If needle not found, return DEVICE_NOT_FOUND.
+ * location in *index.
+ * In the case of a minor device attribute change, such as RAID level, just
+ * return DEVICE_UPDATED, along with the updated device's location in index.
+ * If needle not found, return DEVICE_NOT_FOUND.
*/
static int hpsa_scsi_find_entry(struct hpsa_scsi_dev_t *needle,
struct hpsa_scsi_dev_t *haystack[], int haystack_size,
@@ -794,15 +823,19 @@ static int hpsa_scsi_find_entry(struct hpsa_scsi_dev_t *needle,
#define DEVICE_NOT_FOUND 0
#define DEVICE_CHANGED 1
#define DEVICE_SAME 2
+#define DEVICE_UPDATED 3
for (i = 0; i < haystack_size; i++) {
if (haystack[i] == NULL) /* previously removed. */
continue;
if (SCSI3ADDR_EQ(needle->scsi3addr, haystack[i]->scsi3addr)) {
*index = i;
- if (device_is_the_same(needle, haystack[i]))
+ if (device_is_the_same(needle, haystack[i])) {
+ if (device_updated(needle, haystack[i]))
+ return DEVICE_UPDATED;
return DEVICE_SAME;
- else
+ } else {
return DEVICE_CHANGED;
+ }
}
}
*index = -1;
@@ -838,6 +871,8 @@ static void adjust_hpsa_scsi_table(struct ctlr_info *h, int hostno,
* sd[] and remove them from h->dev[], and for any
* devices which have changed, remove the old device
* info and add the new device info.
+ * If minor device attributes change, just update
+ * the existing device structure.
*/
i = 0;
nremoved = 0;
@@ -858,6 +893,8 @@ static void adjust_hpsa_scsi_table(struct ctlr_info *h, int hostno,
* at the bottom of hpsa_update_scsi_devices()
*/
sd[entry] = NULL;
+ } else if (device_change == DEVICE_UPDATED) {
+ hpsa_scsi_update_entry(h, hostno, i, sd[entry]);
}
i++;
}

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