1 files changed, 254 insertions, 50 deletions

diff --git a/arch/ia64/sn/kernel/xpc_partition.c b/arch/ia64/sn/kernel/xpc_partition.c
index 578265ea9e67..79a0fc4c860c 100644
--- a/arch/ia64/sn/kernel/xpc_partition.c
+++ b/arch/ia64/sn/kernel/xpc_partition.c
@@ -76,11 +76,6 @@ char ____cacheline_aligned
                 xpc_remote_copy_buffer[XPC_RSVD_PAGE_ALIGNED_SIZE];
 
 
-/* systune related variables */
-int xpc_hb_interval = XPC_HB_DEFAULT_INTERVAL;
-int xpc_hb_check_interval = XPC_HB_CHECK_DEFAULT_TIMEOUT;
-
-
 /*
  * Given a nasid, get the physical address of the  partition's reserved page
  * for that nasid. This function returns 0 on any error.
@@ -239,16 +234,21 @@ xpc_rsvd_page_init(void)
         xpc_vars->amos_page = amos_page;  /* save for next load of XPC */
 
 
-        /*
-         * Initialize the activation related AMO variables.
-         */
-        xpc_vars->act_amos = xpc_IPI_init(XP_MAX_PARTITIONS);
-        for (i = 1; i < XP_NASID_MASK_WORDS; i++) {
-                xpc_IPI_init(i + XP_MAX_PARTITIONS);
+        /* 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);
+
         /* export AMO page's physical address to other partitions */
         xpc_vars->amos_page_pa = ia64_tpa((u64) xpc_vars->amos_page);
 
+        /* timestamp of when reserved page was initialized */
+        rp->stamp = CURRENT_TIME;
+
         /*
          * This signifies to the remote partition that our reserved
          * page is initialized.
@@ -387,6 +387,11 @@ xpc_check_remote_hb(void)
         remote_vars = (struct xpc_vars *) xpc_remote_copy_buffer;
 
         for (partid = 1; partid < XP_MAX_PARTITIONS; partid++) {
+
+                if (xpc_exiting) {
+                        break;
+                }
+
                 if (partid == sn_partition_id) {
                         continue;
                 }
@@ -417,7 +422,7 @@ xpc_check_remote_hb(void)
 
                 if (((remote_vars->heartbeat == part->last_heartbeat) &&
                         (remote_vars->kdb_status == 0)) ||
-                             !XPC_HB_ALLOWED(sn_partition_id, remote_vars)) {
+                             !xpc_hb_allowed(sn_partition_id, remote_vars)) {
 
                         XPC_DEACTIVATE_PARTITION(part, xpcNoHeartbeat);
                         continue;
@@ -436,23 +441,23 @@ xpc_check_remote_hb(void)
  */
 static enum xpc_retval
 xpc_get_remote_rp(int nasid, u64 *discovered_nasids,
-                struct xpc_rsvd_page *remote_rp, u64 *remote_rsvd_page_pa)
+                struct xpc_rsvd_page *remote_rp, u64 *remote_rp_pa)
 {
         int bres, i;
 
 
         /* get the reserved page's physical address */
 
-        *remote_rsvd_page_pa = xpc_get_rsvd_page_pa(nasid, (u64) remote_rp,
+        *remote_rp_pa = xpc_get_rsvd_page_pa(nasid, (u64) remote_rp,
                                                 XPC_RSVD_PAGE_ALIGNED_SIZE);
-        if (*remote_rsvd_page_pa == 0) {
+        if (*remote_rp_pa == 0) {
                 return xpcNoRsvdPageAddr;
         }
 
 
         /* pull over the reserved page structure */
 
-        bres = xp_bte_copy(*remote_rsvd_page_pa, ia64_tpa((u64) remote_rp),
+        bres = xp_bte_copy(*remote_rp_pa, ia64_tpa((u64) remote_rp),
                                 XPC_RSVD_PAGE_ALIGNED_SIZE,
                                 (BTE_NOTIFY | BTE_WACQUIRE), NULL);
         if (bres != BTE_SUCCESS) {
@@ -524,6 +529,55 @@ xpc_get_remote_vars(u64 remote_vars_pa, struct xpc_vars *remote_vars)
 
 
 /*
+ * Update the remote partition's info.
+ */
+static void
+xpc_update_partition_info(struct xpc_partition *part, u8 remote_rp_version,
+                struct timespec *remote_rp_stamp, u64 remote_rp_pa,
+                u64 remote_vars_pa, struct xpc_vars *remote_vars)
+{
+        part->remote_rp_version = remote_rp_version;
+        dev_dbg(xpc_part, "  remote_rp_version = 0x%016lx\n",
+                part->remote_rp_version);
+
+        part->remote_rp_stamp = *remote_rp_stamp;
+        dev_dbg(xpc_part, "  remote_rp_stamp (tv_sec = 0x%lx tv_nsec = 0x%lx\n",
+                part->remote_rp_stamp.tv_sec, part->remote_rp_stamp.tv_nsec);
+
+        part->remote_rp_pa = remote_rp_pa;
+        dev_dbg(xpc_part, "  remote_rp_pa = 0x%016lx\n", part->remote_rp_pa);
+
+        part->remote_vars_pa = remote_vars_pa;
+        dev_dbg(xpc_part, "  remote_vars_pa = 0x%016lx\n",
+                part->remote_vars_pa);
+
+        part->last_heartbeat = remote_vars->heartbeat;
+        dev_dbg(xpc_part, "  last_heartbeat = 0x%016lx\n",
+                part->last_heartbeat);
+
+        part->remote_vars_part_pa = remote_vars->vars_part_pa;
+        dev_dbg(xpc_part, "  remote_vars_part_pa = 0x%016lx\n",
+                part->remote_vars_part_pa);
+
+        part->remote_act_nasid = remote_vars->act_nasid;
+        dev_dbg(xpc_part, "  remote_act_nasid = 0x%x\n",
+                part->remote_act_nasid);
+
+        part->remote_act_phys_cpuid = remote_vars->act_phys_cpuid;
+        dev_dbg(xpc_part, "  remote_act_phys_cpuid = 0x%x\n",
+                part->remote_act_phys_cpuid);
+
+        part->remote_amos_page_pa = remote_vars->amos_page_pa;
+        dev_dbg(xpc_part, "  remote_amos_page_pa = 0x%lx\n",
+                part->remote_amos_page_pa);
+
+        part->remote_vars_version = remote_vars->version;
+        dev_dbg(xpc_part, "  remote_vars_version = 0x%x\n",
+                part->remote_vars_version);
+}
+
+
+/*
  * Prior code has determine the nasid which generated an IPI.  Inspect
  * that nasid to determine if its partition needs to be activated or
  * deactivated.
@@ -542,8 +596,12 @@ xpc_identify_act_IRQ_req(int nasid)
 {
         struct xpc_rsvd_page *remote_rp;
         struct xpc_vars *remote_vars;
-        u64 remote_rsvd_page_pa;
+        u64 remote_rp_pa;
         u64 remote_vars_pa;
+        int remote_rp_version;
+        int reactivate = 0;
+        int stamp_diff;
+        struct timespec remote_rp_stamp = { 0, 0 };
         partid_t partid;
         struct xpc_partition *part;
         enum xpc_retval ret;
@@ -553,7 +611,7 @@ xpc_identify_act_IRQ_req(int nasid)
 
         remote_rp = (struct xpc_rsvd_page *) xpc_remote_copy_buffer;
 
-        ret = xpc_get_remote_rp(nasid, NULL, remote_rp, &remote_rsvd_page_pa);
+        ret = xpc_get_remote_rp(nasid, NULL, remote_rp, &remote_rp_pa);
         if (ret != xpcSuccess) {
                 dev_warn(xpc_part, "unable to get reserved page from nasid %d, "
                         "which sent interrupt, reason=%d\n", nasid, ret);
@@ -561,6 +619,10 @@ xpc_identify_act_IRQ_req(int nasid)
         }
 
         remote_vars_pa = remote_rp->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;
         part = &xpc_partitions[partid];
 
@@ -586,44 +648,117 @@ xpc_identify_act_IRQ_req(int nasid)
                 "%ld:0x%lx\n", (int) nasid, (int) partid, part->act_IRQ_rcvd,
                 remote_vars->heartbeat, remote_vars->heartbeating_to_mask);
 
+        if (xpc_partition_disengaged(part) &&
+                                        part->act_state == XPC_P_INACTIVE) {
 
-        if (part->act_state == XPC_P_INACTIVE) {
+                xpc_update_partition_info(part, remote_rp_version,
+                                        &remote_rp_stamp, remote_rp_pa,
+                                        remote_vars_pa, remote_vars);
 
-                part->remote_rp_pa = remote_rsvd_page_pa;
-                dev_dbg(xpc_part, "  remote_rp_pa = 0x%016lx\n",
-                        part->remote_rp_pa);
+                if (XPC_SUPPORTS_DISENGAGE_REQUEST(part->remote_vars_version)) {
+                        if (xpc_partition_disengage_requested(1UL << partid)) {
+                                /*
+                                 * Other side is waiting on us to disengage,
+                                 * even though we already have.
+                                 */
+                                return;
+                        }
+                } else {
+                        /* other side doesn't support disengage requests */
+                        xpc_clear_partition_disengage_request(1UL << partid);
+                }
 
-                part->remote_vars_pa = remote_vars_pa;
-                dev_dbg(xpc_part, "  remote_vars_pa = 0x%016lx\n",
-                        part->remote_vars_pa);
+                xpc_activate_partition(part);
+                return;
+        }
 
-                part->last_heartbeat = remote_vars->heartbeat;
-                dev_dbg(xpc_part, "  last_heartbeat = 0x%016lx\n",
-                        part->last_heartbeat);
+        DBUG_ON(part->remote_rp_version == 0);
+        DBUG_ON(part->remote_vars_version == 0);
+
+        if (!XPC_SUPPORTS_RP_STAMP(part->remote_rp_version)) {
+                DBUG_ON(XPC_SUPPORTS_DISENGAGE_REQUEST(part->
+                                                        remote_vars_version));
+
+                if (!XPC_SUPPORTS_RP_STAMP(remote_rp_version)) {
+                        DBUG_ON(XPC_SUPPORTS_DISENGAGE_REQUEST(remote_vars->
+                                                                version));
+                        /* see if the other side rebooted */
+                        if (part->remote_amos_page_pa ==
+                                remote_vars->amos_page_pa &&
+                                        xpc_hb_allowed(sn_partition_id,
+                                                                remote_vars)) {
+                                /* doesn't look that way, so ignore the IPI */
+                                return;
+                        }
+                }
 
-                part->remote_vars_part_pa = remote_vars->vars_part_pa;
-                dev_dbg(xpc_part, "  remote_vars_part_pa = 0x%016lx\n",
-                        part->remote_vars_part_pa);
+                /*
+                 * Other side rebooted and previous XPC didn't support the
+                 * disengage request, so we don't need to do anything special.
+                 */
 
-                part->remote_act_nasid = remote_vars->act_nasid;
-                dev_dbg(xpc_part, "  remote_act_nasid = 0x%x\n",
-                        part->remote_act_nasid);
+                xpc_update_partition_info(part, remote_rp_version,
+                                                &remote_rp_stamp, remote_rp_pa,
+                                                remote_vars_pa, remote_vars);
+                part->reactivate_nasid = nasid;
+                XPC_DEACTIVATE_PARTITION(part, xpcReactivating);
+                return;
+        }
 
-                part->remote_act_phys_cpuid = remote_vars->act_phys_cpuid;
-                dev_dbg(xpc_part, "  remote_act_phys_cpuid = 0x%x\n",
-                        part->remote_act_phys_cpuid);
+        DBUG_ON(!XPC_SUPPORTS_DISENGAGE_REQUEST(part->remote_vars_version));
 
-                part->remote_amos_page_pa = remote_vars->amos_page_pa;
-                dev_dbg(xpc_part, "  remote_amos_page_pa = 0x%lx\n",
-                        part->remote_amos_page_pa);
+        if (!XPC_SUPPORTS_RP_STAMP(remote_rp_version)) {
+                DBUG_ON(!XPC_SUPPORTS_DISENGAGE_REQUEST(remote_vars->version));
 
-                xpc_activate_partition(part);
+                /*
+                 * Other side rebooted and previous XPC did support the
+                 * disengage request, but the new one doesn't.
+                 */
 
-        } else if (part->remote_amos_page_pa != remote_vars->amos_page_pa ||
-                        !XPC_HB_ALLOWED(sn_partition_id, remote_vars)) {
+                xpc_clear_partition_engaged(1UL << partid);
+                xpc_clear_partition_disengage_request(1UL << partid);
 
+                xpc_update_partition_info(part, remote_rp_version,
+                                                &remote_rp_stamp, remote_rp_pa,
+                                                remote_vars_pa, remote_vars);
+                reactivate = 1;
+
+        } else {
+                DBUG_ON(!XPC_SUPPORTS_DISENGAGE_REQUEST(remote_vars->version));
+
+                stamp_diff = xpc_compare_stamps(&part->remote_rp_stamp,
+                                                        &remote_rp_stamp);
+                if (stamp_diff != 0) {
+                        DBUG_ON(stamp_diff >= 0);
+
+                        /*
+                         * Other side rebooted and the previous XPC did support
+                         * the disengage request, as does the new one.
+                         */
+
+                        DBUG_ON(xpc_partition_engaged(1UL << partid));
+                        DBUG_ON(xpc_partition_disengage_requested(1UL <<
+                                                                partid));
+
+                        xpc_update_partition_info(part, remote_rp_version,
+                                                &remote_rp_stamp, remote_rp_pa,
+                                                remote_vars_pa, remote_vars);
+                        reactivate = 1;
+                }
+        }
+
+        if (!xpc_partition_disengaged(part)) {
+                /* still waiting on other side to disengage from us */
+                return;
+        }
+
+        if (reactivate) {
                 part->reactivate_nasid = nasid;
                 XPC_DEACTIVATE_PARTITION(part, xpcReactivating);
+
+        } else if (XPC_SUPPORTS_DISENGAGE_REQUEST(part->remote_vars_version) &&
+                        xpc_partition_disengage_requested(1UL << partid)) {
+                XPC_DEACTIVATE_PARTITION(part, xpcOtherGoingDown);
         }
 }
 
@@ -646,12 +781,16 @@ xpc_identify_act_IRQ_sender(void)
         struct xpc_rsvd_page *rp = (struct xpc_rsvd_page *) xpc_rsvd_page;
 
 
-        act_amos = xpc_vars->act_amos;
+        act_amos = xpc_vars->amos_page + XPC_ACTIVATE_IRQ_AMOS;
 
 
         /* scan through act AMO variable looking for non-zero entries */
         for (word = 0; word < XP_NASID_MASK_WORDS; word++) {
 
+                if (xpc_exiting) {
+                        break;
+                }
+
                 nasid_mask = xpc_IPI_receive(&act_amos[word]);
                 if (nasid_mask == 0) {
                         /* no IRQs from nasids in this variable */
@@ -688,6 +827,55 @@ xpc_identify_act_IRQ_sender(void)
 
 
 /*
+ * See if the other side has responded to a partition disengage request
+ * from us.
+ */
+int
+xpc_partition_disengaged(struct xpc_partition *part)
+{
+        partid_t partid = XPC_PARTID(part);
+        int disengaged;
+
+
+        disengaged = (xpc_partition_engaged(1UL << partid) == 0);
+        if (part->disengage_request_timeout) {
+                if (!disengaged) {
+                        if (jiffies < part->disengage_request_timeout) {
+                                /* timelimit hasn't been reached yet */
+                                return 0;
+                        }
+
+                        /*
+                         * Other side hasn't responded to our disengage
+                         * request in a timely fashion, so assume it's dead.
+                         */
+
+                        xpc_clear_partition_engaged(1UL << partid);
+                        disengaged = 1;
+                }
+                part->disengage_request_timeout = 0;
+
+                /* cancel the timer function, provided it's not us */
+                if (!in_interrupt()) {
+                        del_singleshot_timer_sync(&part->
+                                                      disengage_request_timer);
+                }
+
+                DBUG_ON(part->act_state != XPC_P_DEACTIVATING &&
+                                        part->act_state != XPC_P_INACTIVE);
+                if (part->act_state != XPC_P_INACTIVE) {
+                        xpc_wakeup_channel_mgr(part);
+                }
+
+                if (XPC_SUPPORTS_DISENGAGE_REQUEST(part->remote_vars_version)) {
+                        xpc_cancel_partition_disengage_request(part);
+                }
+        }
+        return disengaged;
+}
+
+
+/*
  * Mark specified partition as active.
  */
 enum xpc_retval
@@ -721,7 +909,6 @@ xpc_deactivate_partition(const int line, struct xpc_partition *part,
                                 enum xpc_retval reason)
 {
         unsigned long irq_flags;
-        partid_t partid = XPC_PARTID(part);
 
 
         spin_lock_irqsave(&part->act_lock, irq_flags);
@@ -749,17 +936,27 @@ xpc_deactivate_partition(const int line, struct xpc_partition *part,
 
         spin_unlock_irqrestore(&part->act_lock, irq_flags);
 
-        XPC_DISALLOW_HB(partid, xpc_vars);
+        if (XPC_SUPPORTS_DISENGAGE_REQUEST(part->remote_vars_version)) {
+                xpc_request_partition_disengage(part);
+                xpc_IPI_send_disengage(part);
+
+                /* set a timelimit on the disengage request */
+                part->disengage_request_timeout = jiffies +
+                                        (XPC_DISENGAGE_REQUEST_TIMELIMIT * HZ);
+                part->disengage_request_timer.expires =
+                                        part->disengage_request_timeout;
+                add_timer(&part->disengage_request_timer);
+        }
 
         dev_dbg(xpc_part, "bringing partition %d down, reason = %d\n", partid,
                 reason);
 
-        xpc_partition_down(part, reason);
+        xpc_partition_going_down(part, reason);
 }
 
 
 /*
- * Mark specified partition as active.
+ * Mark specified partition as inactive.
  */
 void
 xpc_mark_partition_inactive(struct xpc_partition *part)
@@ -792,7 +989,7 @@ xpc_discovery(void)
         void *remote_rp_base;
         struct xpc_rsvd_page *remote_rp;
         struct xpc_vars *remote_vars;
-        u64 remote_rsvd_page_pa;
+        u64 remote_rp_pa;
         u64 remote_vars_pa;
         int region;
         int max_regions;
@@ -877,7 +1074,7 @@ xpc_discovery(void)
                         /* pull over the reserved page structure */
 
                         ret = xpc_get_remote_rp(nasid, discovered_nasids,
-                                              remote_rp, &remote_rsvd_page_pa);
+                                              remote_rp, &remote_rp_pa);
                         if (ret != xpcSuccess) {
                                 dev_dbg(xpc_part, "unable to get reserved page "
                                         "from nasid %d, reason=%d\n", nasid,
@@ -948,6 +1145,13 @@ xpc_discovery(void)
                                 remote_vars->act_nasid,
                                 remote_vars->act_phys_cpuid);
 
+                        if (XPC_SUPPORTS_DISENGAGE_REQUEST(remote_vars->
+                                                                version)) {
+                                part->remote_amos_page_pa =
+                                                remote_vars->amos_page_pa;
+                                xpc_mark_partition_disengaged(part);
+                                xpc_cancel_partition_disengage_request(part);
+                        }
                         xpc_IPI_send_activate(remote_vars);
                 }
         }