[SCSI] hpsa: eliminate 8 external target limitation

Driver limits SAS external target IDs to range 1-8.
Need to increase limit and clean up overlapping concepts of targets and paths
in the code.

There are several defined constants that control this:
HPSA_MAX_TARGETS_PER_CTLR     16
MAX_MSA2XXX_ENCLOSURES        32
HPSA_MAX_PATHS                8

We can condense this to one constant:
MAX_EXT_TARGETS               32

SAS switches allow for 8 connections, and there is capacity for 4 switches per
enclosure in largest blade enclosure type.

Signed-off-by: Scott Teel <scott.teel@hp.com>
Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

2 files changed, 10 insertions, 11 deletions

diff --git a/drivers/scsi/hpsa.c b/drivers/scsi/hpsa.c
index 5a795e6e9947..c8db43e9a38a 100644
--- a/drivers/scsi/hpsa.c
+++ b/drivers/scsi/hpsa.c
@@ -1694,9 +1694,9 @@ static int add_msa2xxx_enclosure_device(struct ctlr_info *h,
         if (is_scsi_rev_5(h))
                 return 0; /* p1210m doesn't need to do this. */
 
-        if (*nmsa2xxx_enclosures >= MAX_MSA2XXX_ENCLOSURES) {
-                dev_warn(&h->pdev->dev, "Maximum number of MSA2XXX "
-                        "enclosures exceeded.  Check your hardware "
+        if (*nmsa2xxx_enclosures >= MAX_EXT_TARGETS) {
+                dev_warn(&h->pdev->dev, "Maximum number of external "
+                        "target devices exceeded.  Check your hardware "
                         "configuration.");
                 return 0;
         }
@@ -1802,7 +1802,7 @@ static void hpsa_update_scsi_devices(struct ctlr_info *h, int hostno)
         int reportlunsize = sizeof(*physdev_list) + HPSA_MAX_PHYS_LUN * 8;
         int i, nmsa2xxx_enclosures, ndevs_to_allocate;
         int raid_ctlr_position;
-        DECLARE_BITMAP(lunzerobits, HPSA_MAX_TARGETS_PER_CTLR);
+        DECLARE_BITMAP(lunzerobits, MAX_EXT_TARGETS);
 
         currentsd = kzalloc(sizeof(*currentsd) * HPSA_MAX_DEVICES, GFP_KERNEL);
         physdev_list = kzalloc(reportlunsize, GFP_KERNEL);
@@ -1819,11 +1819,11 @@ static void hpsa_update_scsi_devices(struct ctlr_info *h, int hostno)
                         logdev_list, &nlogicals))
                 goto out;
 
-        /* We might see up to 32 MSA2xxx enclosures, actually 8 of them
-         * but each of them 4 times through different paths.  The plus 1
-         * is for the RAID controller.
+        /* We might see up to the maximum number of logical and physical disks
+         * plus external target devices, and a device for the local RAID
+         * controller.
          */
-        ndevs_to_allocate = nphysicals + nlogicals + MAX_MSA2XXX_ENCLOSURES + 1;
+        ndevs_to_allocate = nphysicals + nlogicals + MAX_EXT_TARGETS + 1;
 
         /* Allocate the per device structures */
         for (i = 0; i < ndevs_to_allocate; i++) {
diff --git a/drivers/scsi/hpsa_cmd.h b/drivers/scsi/hpsa_cmd.h
index 516d6e53c7e6..8049815d8c1e 100644
--- a/drivers/scsi/hpsa_cmd.h
+++ b/drivers/scsi/hpsa_cmd.h
@@ -122,12 +122,11 @@ union u64bit {
 };
 
 /* FIXME this is a per controller value (barf!) */
-#define HPSA_MAX_TARGETS_PER_CTLR 16
 #define HPSA_MAX_LUN 1024
 #define HPSA_MAX_PHYS_LUN 1024
-#define MAX_MSA2XXX_ENCLOSURES 32
+#define MAX_EXT_TARGETS 32
 #define HPSA_MAX_DEVICES (HPSA_MAX_PHYS_LUN + HPSA_MAX_LUN + \
-        MAX_MSA2XXX_ENCLOSURES + 1) /* + 1 is for the controller itself */
+        MAX_EXT_TARGETS + 1) /* + 1 is for the controller itself */
 
 /* SCSI-3 Commands */
 #pragma pack(1)