sgi-xp: prepare xpc_rsvd_page to work on either sn2 or uv hardware

Prepare XPC's reserved page header to work for either sn2 or uv.

Signed-off-by: Dean Nelson <dcn@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 44 insertions, 105 deletions

diff --git a/drivers/misc/sgi-xp/xpc_partition.c b/drivers/misc/sgi-xp/xpc_partition.c
index 6c82f2050974..1db84cb49143 100644
--- a/drivers/misc/sgi-xp/xpc_partition.c
+++ b/drivers/misc/sgi-xp/xpc_partition.c
@@ -20,7 +20,6 @@
 #include <linux/cache.h>
 #include <linux/mmzone.h>
 #include <linux/nodemask.h>
-#include <asm/uncached.h>
 #include <asm/sn/intr.h>
 #include <asm/sn/sn_sal.h>
 #include <asm/sn/nodepda.h>
@@ -44,11 +43,10 @@ u64 xpc_prot_vec[MAX_NUMNODES];
 struct xpc_rsvd_page *xpc_rsvd_page;
 static u64 *xpc_part_nasids;
 static u64 *xpc_mach_nasids;
-struct xpc_vars *xpc_vars;
-struct xpc_vars_part *xpc_vars_part;
 
-static int xp_nasid_mask_bytes; /* actual size in bytes of nasid mask */
-static int xp_nasid_mask_words; /* actual size in words of nasid mask */
+/* >>> next two variables should be 'xpc_' if they remain here */
+static int xp_sizeof_nasid_mask;        /* actual size in bytes of nasid mask */
+int xp_nasid_mask_words;        /* actual size in words of nasid mask */
 
 struct xpc_partition *xpc_partitions;
 
@@ -150,12 +148,10 @@ xpc_get_rsvd_page_pa(int nasid)
  * communications.
  */
 struct xpc_rsvd_page *
-xpc_rsvd_page_init(void)
+xpc_setup_rsvd_page(void)
 {
         struct xpc_rsvd_page *rp;
-        AMO_t *amos_page;
-        u64 rp_pa, nasid_array = 0;
-        int i, ret;
+        u64 rp_pa;
 
         /* get the local reserved page's address */
 
@@ -168,110 +164,44 @@ xpc_rsvd_page_init(void)
         }
         rp = (struct xpc_rsvd_page *)__va(rp_pa);
 
-        if (rp->partid != sn_partition_id) {
-                dev_err(xpc_part, "the reserved page's partid of %d should be "
-                        "%d\n", rp->partid, sn_partition_id);
+        if (rp->SAL_version < 3) {
+                /* SAL_versions < 3 had a SAL_partid defined as a u8 */
+                rp->SAL_partid &= 0xff;
+        }
+        BUG_ON(rp->SAL_partid != sn_partition_id);
+
+        if (rp->SAL_partid < 0 || rp->SAL_partid >= xp_max_npartitions) {
+                dev_err(xpc_part, "the reserved page's partid of %d is outside "
+                        "supported range (< 0 || >= %d)\n", rp->SAL_partid,
+                        xp_max_npartitions);
                 return NULL;
         }
 
         rp->version = XPC_RP_VERSION;
+        rp->max_npartitions = xp_max_npartitions;
 
         /* establish the actual sizes of the nasid masks */
         if (rp->SAL_version == 1) {
                 /* SAL_version 1 didn't set the nasids_size field */
-                rp->nasids_size = 128;
+                rp->SAL_nasids_size = 128;
         }
-        xp_nasid_mask_bytes = rp->nasids_size;
-        xp_nasid_mask_words = xp_nasid_mask_bytes / 8;
+        xp_sizeof_nasid_mask = rp->SAL_nasids_size;
+        xp_nasid_mask_words = DIV_ROUND_UP(xp_sizeof_nasid_mask,
+                                           BYTES_PER_WORD);
 
         /* setup the pointers to the various items in the reserved page */
         xpc_part_nasids = XPC_RP_PART_NASIDS(rp);
         xpc_mach_nasids = XPC_RP_MACH_NASIDS(rp);
-        xpc_vars = XPC_RP_VARS(rp);
-        xpc_vars_part = XPC_RP_VARS_PART(rp);
 
-        /*
-         * Before clearing xpc_vars, see if a page of AMOs had been previously
-         * allocated. If not we'll need to allocate one and set permissions
-         * so that cross-partition AMOs are allowed.
-         *
-         * The allocated AMO page needs MCA reporting to remain disabled after
-         * XPC has unloaded.  To make this work, we keep a copy of the pointer
-         * to this page (i.e., amos_page) in the struct xpc_vars structure,
-         * which is pointed to by the reserved page, and re-use that saved copy
-         * on subsequent loads of XPC. This AMO page is never freed, and its
-         * memory protections are never restricted.
-         */
-        amos_page = xpc_vars->amos_page;
-        if (amos_page == NULL) {
-                amos_page = (AMO_t *)TO_AMO(uncached_alloc_page(0, 1));
-                if (amos_page == NULL) {
-                        dev_err(xpc_part, "can't allocate page of AMOs\n");
-                        return NULL;
-                }
-
-                /*
-                 * Open up AMO-R/W to cpu.  This is done for Shub 1.1 systems
-                 * when xpc_allow_IPI_ops() is called via xpc_hb_init().
-                 */
-                if (!enable_shub_wars_1_1()) {
-                        ret = sn_change_memprotect(ia64_tpa((u64)amos_page),
-                                                   PAGE_SIZE,
-                                                   SN_MEMPROT_ACCESS_CLASS_1,
-                                                   &nasid_array);
-                        if (ret != 0) {
-                                dev_err(xpc_part, "can't change memory "
-                                        "protections\n");
-                                uncached_free_page(__IA64_UNCACHED_OFFSET |
-                                                   TO_PHYS((u64)amos_page), 1);
-                                return NULL;
-                        }
-                }
-        } else if (!IS_AMO_ADDRESS((u64)amos_page)) {
-                /*
-                 * EFI's XPBOOT can also set amos_page in the reserved page,
-                 * but it happens to leave it as an uncached physical address
-                 * and we need it to be an uncached virtual, so we'll have to
-                 * convert it.
-                 */
-                if (!IS_AMO_PHYS_ADDRESS((u64)amos_page)) {
-                        dev_err(xpc_part, "previously used amos_page address "
-                                "is bad = 0x%p\n", (void *)amos_page);
-                        return NULL;
-                }
-                amos_page = (AMO_t *)TO_AMO((u64)amos_page);
-        }
-
-        /* clear xpc_vars */
-        memset(xpc_vars, 0, sizeof(struct xpc_vars));
-
-        xpc_vars->version = XPC_V_VERSION;
-        xpc_vars->act_nasid = cpuid_to_nasid(0);
-        xpc_vars->act_phys_cpuid = cpu_physical_id(0);
-        xpc_vars->vars_part_pa = __pa(xpc_vars_part);
-        xpc_vars->amos_page_pa = ia64_tpa((u64)amos_page);
-        xpc_vars->amos_page = amos_page;        /* save for next load of XPC */
-
-        /* clear xpc_vars_part */
-        memset((u64 *)xpc_vars_part, 0, sizeof(struct xpc_vars_part) *
-               xp_max_npartitions);
-
-        /* initialize the activate IRQ related AMO variables */
-        for (i = 0; i < xp_nasid_mask_words; i++)
-                (void)xpc_IPI_init(XPC_ACTIVATE_IRQ_AMOS + i);
-
-        /* initialize the engaged remote partitions related AMO variables */
-        (void)xpc_IPI_init(XPC_ENGAGED_PARTITIONS_AMO);
-        (void)xpc_IPI_init(XPC_DISENGAGE_REQUEST_AMO);
-
-        /* timestamp of when reserved page was setup by XPC */
-        rp->stamp = CURRENT_TIME;
+        if (xpc_rsvd_page_init(rp) != xpSuccess)
+                return NULL;
 
         /*
+         * Set timestamp of when reserved page was setup by XPC.
          * This signifies to the remote partition that our reserved
          * page is initialized.
          */
-        rp->vars_pa = __pa(xpc_vars);
+        rp->stamp = CURRENT_TIME;
 
         return rp;
 }
@@ -465,7 +395,7 @@ xpc_get_remote_rp(int nasid, u64 *discovered_nasids,
 
         /* pull over the reserved page header and part_nasids mask */
         ret = xp_remote_memcpy(remote_rp, (void *)*remote_rp_pa,
-                               XPC_RP_HEADER_SIZE + xp_nasid_mask_bytes);
+                               XPC_RP_HEADER_SIZE + xp_sizeof_nasid_mask);
         if (ret != xpSuccess)
                 return ret;
 
@@ -476,19 +406,28 @@ xpc_get_remote_rp(int nasid, u64 *discovered_nasids,
                         discovered_nasids[i] |= remote_part_nasids[i];
         }
 
-        /* check that the partid is for another partition */
+        /* check that the partid is valid and is for another partition */
 
-        if (remote_rp->partid < 0 || remote_rp->partid >= xp_max_npartitions)
+        if (remote_rp->SAL_partid < 0 ||
+            remote_rp->SAL_partid >= xp_max_npartitions) {
                 return xpInvalidPartid;
+        }
 
-        if (remote_rp->partid == sn_partition_id)
+        if (remote_rp->SAL_partid == sn_partition_id)
                 return xpLocalPartid;
 
+        /* see if the rest of the reserved page has been set up by XPC */
+        if (timespec_equal(&remote_rp->stamp, &ZERO_STAMP))
+                return xpRsvdPageNotSet;
+
         if (XPC_VERSION_MAJOR(remote_rp->version) !=
             XPC_VERSION_MAJOR(XPC_RP_VERSION)) {
                 return xpBadVersion;
         }
 
+        if (remote_rp->max_npartitions <= sn_partition_id)
+                return xpInvalidPartid;
+
         return xpSuccess;
 }
 
@@ -592,7 +531,7 @@ xpc_identify_act_IRQ_req(int nasid)
         int remote_rp_version;
         int reactivate = 0;
         int stamp_diff;
-        struct timespec remote_rp_stamp = { 0, 0 };
+        struct timespec remote_rp_stamp = { 0, 0 }; /*>>> ZERO_STAMP */
         short partid;
         struct xpc_partition *part;
         enum xp_retval ret;
@@ -608,12 +547,12 @@ xpc_identify_act_IRQ_req(int nasid)
                 return;
         }
 
-        remote_vars_pa = remote_rp->vars_pa;
+        remote_vars_pa = remote_rp->sn.vars_pa;
         remote_rp_version = remote_rp->version;
         if (XPC_SUPPORTS_RP_STAMP(remote_rp_version))
                 remote_rp_stamp = remote_rp->stamp;
 
-        partid = remote_rp->partid;
+        partid = remote_rp->SAL_partid;
         part = &xpc_partitions[partid];
 
         /* pull over the cross partition variables */
@@ -977,7 +916,7 @@ xpc_discovery(void)
         enum xp_retval ret;
 
         remote_rp = xpc_kmalloc_cacheline_aligned(XPC_RP_HEADER_SIZE +
-                                                  xp_nasid_mask_bytes,
+                                                  xp_sizeof_nasid_mask,
                                                   GFP_KERNEL, &remote_rp_base);
         if (remote_rp == NULL)
                 return;
@@ -1063,9 +1002,9 @@ xpc_discovery(void)
                                 continue;
                         }
 
-                        remote_vars_pa = remote_rp->vars_pa;
+                        remote_vars_pa = remote_rp->sn.vars_pa;
 
-                        partid = remote_rp->partid;
+                        partid = remote_rp->SAL_partid;
                         part = &xpc_partitions[partid];
 
                         /* pull over the cross partition variables */
@@ -1155,5 +1094,5 @@ xpc_initiate_partid_to_nasids(short partid, void *nasid_mask)
         part_nasid_pa = (u64)XPC_RP_PART_NASIDS(part->remote_rp_pa);
 
         return xp_remote_memcpy(nasid_mask, (void *)part_nasid_pa,
-                                xp_nasid_mask_bytes);
+                                xp_sizeof_nasid_mask);
 }