[SCSI] qla2xxx: fix to honor ignored parameters in sysfs attributes

This is a patch to fix 'segmentation fault' issue which was initiated
by Richard Lary <rlary@us.ibm.com>.  Thanks again Richard.

- on following sysfs attritute function, changes have made so that both
  count and offset input parameters are honored by the functions.
    = qla2x00_sysfs_read_nvram()
    = qla2x00_sysfs_read_vpd()
- made changes so that NVRAM data to be cached to minimize H/W accesses
  during agent querying of the driver's.

Signed-off-by: Seokmann Ju <seokmann.ju@qlogic.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

3 files changed, 38 insertions, 24 deletions

diff --git a/drivers/scsi/qla2xxx/qla_attr.c b/drivers/scsi/qla2xxx/qla_attr.c
index 1612f9200a52..0f2a9f5d801c 100644
--- a/drivers/scsi/qla2xxx/qla_attr.c
+++ b/drivers/scsi/qla2xxx/qla_attr.c
@@ -91,18 +91,20 @@ qla2x00_sysfs_read_nvram(struct kobject *kobj,
 {
         struct scsi_qla_host *ha = to_qla_host(dev_to_shost(container_of(kobj,
             struct device, kobj)));
-        unsigned long   flags;
+        int             size = ha->nvram_size;
+        char            *nvram_cache = ha->nvram;
 
-        if (!capable(CAP_SYS_ADMIN) || off != 0)
+        if (!capable(CAP_SYS_ADMIN) || off > size || count == 0)
                 return 0;
+        if (off + count > size) {
+                size -= off;
+                count = size;
+        }
 
-        /* Read NVRAM. */
-        spin_lock_irqsave(&ha->hardware_lock, flags);
-        ha->isp_ops->read_nvram(ha, (uint8_t *)buf, ha->nvram_base,
-            ha->nvram_size);
-        spin_unlock_irqrestore(&ha->hardware_lock, flags);
+        /* Read NVRAM data from cache. */
+        memcpy(buf, &nvram_cache[off], count);
 
-        return ha->nvram_size;
+        return count;
 }
 
 static ssize_t
@@ -144,6 +146,8 @@ qla2x00_sysfs_write_nvram(struct kobject *kobj,
         /* Write NVRAM. */
         spin_lock_irqsave(&ha->hardware_lock, flags);
         ha->isp_ops->write_nvram(ha, (uint8_t *)buf, ha->nvram_base, count);
+        ha->isp_ops->read_nvram(ha, (uint8_t *)&ha->nvram, ha->nvram_base,
+            count);
         spin_unlock_irqrestore(&ha->hardware_lock, flags);
 
         set_bit(ISP_ABORT_NEEDED, &ha->dpc_flags);
@@ -298,18 +302,20 @@ qla2x00_sysfs_read_vpd(struct kobject *kobj,
 {
         struct scsi_qla_host *ha = to_qla_host(dev_to_shost(container_of(kobj,
             struct device, kobj)));
-        unsigned long flags;
+        int           size = ha->vpd_size;
+        char          *vpd_cache = ha->vpd;
 
-        if (!capable(CAP_SYS_ADMIN) || off != 0)
+        if (!capable(CAP_SYS_ADMIN) || off > size || count == 0)
                 return 0;
+        if (off + count > size) {
+                size -= off;
+                count = size;
+        }
 
-        /* Read NVRAM. */
-        spin_lock_irqsave(&ha->hardware_lock, flags);
-        ha->isp_ops->read_nvram(ha, (uint8_t *)buf, ha->vpd_base,
-            ha->vpd_size);
-        spin_unlock_irqrestore(&ha->hardware_lock, flags);
+        /* Read NVRAM data from cache. */
+        memcpy(buf, &vpd_cache[off], count);
 
-        return ha->vpd_size;
+        return count;
 }
 
 static ssize_t
@@ -327,6 +333,7 @@ qla2x00_sysfs_write_vpd(struct kobject *kobj,
         /* Write NVRAM. */
         spin_lock_irqsave(&ha->hardware_lock, flags);
         ha->isp_ops->write_nvram(ha, (uint8_t *)buf, ha->vpd_base, count);
+        ha->isp_ops->read_nvram(ha, (uint8_t *)ha->vpd, ha->vpd_base, count);
         spin_unlock_irqrestore(&ha->hardware_lock, flags);
 
         return count;
diff --git a/drivers/scsi/qla2xxx/qla_def.h b/drivers/scsi/qla2xxx/qla_def.h
index 0c9f36c8a248..27ae3a532a55 100644
--- a/drivers/scsi/qla2xxx/qla_def.h
+++ b/drivers/scsi/qla2xxx/qla_def.h
@@ -2340,10 +2340,14 @@ typedef struct scsi_qla_host {
         uint8_t         serial2;
 
         /* NVRAM configuration data */
+#define MAX_NVRAM_SIZE  4096
+#define VPD_OFFSET      MAX_NVRAM_SIZE / 2
         uint16_t        nvram_size;
         uint16_t        nvram_base;
+        void            *nvram;
         uint16_t        vpd_size;
         uint16_t        vpd_base;
+        void            *vpd;
 
         uint16_t        loop_reset_delay;
         uint8_t         retry_count;
diff --git a/drivers/scsi/qla2xxx/qla_init.c b/drivers/scsi/qla2xxx/qla_init.c
index 5ec798c2bf13..374abe19b547 100644
--- a/drivers/scsi/qla2xxx/qla_init.c
+++ b/drivers/scsi/qla2xxx/qla_init.c
@@ -1461,8 +1461,8 @@ qla2x00_nvram_config(scsi_qla_host_t *ha)
         uint16_t        cnt;
         uint8_t         *dptr1, *dptr2;
         init_cb_t       *icb = ha->init_cb;
-        nvram_t         *nv = (nvram_t *)ha->request_ring;
-        uint8_t         *ptr = (uint8_t *)ha->request_ring;
+        nvram_t         *nv = ha->nvram;
+        uint8_t         *ptr = ha->nvram;
         struct device_reg_2xxx __iomem *reg = &ha->iobase->isp;
 
         rval = QLA_SUCCESS;
@@ -1480,8 +1480,7 @@ qla2x00_nvram_config(scsi_qla_host_t *ha)
                 chksum += *ptr++;
 
         DEBUG5(printk("scsi(%ld): Contents of NVRAM\n", ha->host_no));
-        DEBUG5(qla2x00_dump_buffer((uint8_t *)ha->request_ring,
-            ha->nvram_size));
+        DEBUG5(qla2x00_dump_buffer((uint8_t *)nv, ha->nvram_size));
 
         /* Bad NVRAM data, set defaults parameters. */
         if (chksum || nv->id[0] != 'I' || nv->id[1] != 'S' ||
@@ -3500,7 +3499,7 @@ qla24xx_nvram_config(scsi_qla_host_t *ha)
 
         rval = QLA_SUCCESS;
         icb = (struct init_cb_24xx *)ha->init_cb;
-        nv = (struct nvram_24xx *)ha->request_ring;
+        nv = ha->nvram;
 
         /* Determine NVRAM starting address. */
         ha->nvram_size = sizeof(struct nvram_24xx);
@@ -3512,7 +3511,12 @@ qla24xx_nvram_config(scsi_qla_host_t *ha)
                 ha->vpd_base = FA_NVRAM_VPD1_ADDR;
         }
 
-        /* Get NVRAM data and calculate checksum. */
+        /* Get VPD data into cache */
+        ha->vpd = ha->nvram + VPD_OFFSET;
+        ha->isp_ops->read_nvram(ha, (uint8_t *)ha->vpd,
+            ha->nvram_base - FA_NVRAM_FUNC0_ADDR, FA_NVRAM_VPD_SIZE * 4);
+
+        /* Get NVRAM data into cache and calculate checksum. */
         dptr = (uint32_t *)nv;
         ha->isp_ops->read_nvram(ha, (uint8_t *)dptr, ha->nvram_base,
             ha->nvram_size);
@@ -3520,8 +3524,7 @@ qla24xx_nvram_config(scsi_qla_host_t *ha)
                 chksum += le32_to_cpu(*dptr++);
 
         DEBUG5(printk("scsi(%ld): Contents of NVRAM\n", ha->host_no));
-        DEBUG5(qla2x00_dump_buffer((uint8_t *)ha->request_ring,
-            ha->nvram_size));
+        DEBUG5(qla2x00_dump_buffer((uint8_t *)nv, ha->nvram_size));
 
         /* Bad NVRAM data, set defaults parameters. */
         if (chksum || nv->id[0] != 'I' || nv->id[1] != 'S' || nv->id[2] != 'P'