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-rw-r--r--drivers/misc/sgi-xp/xpc_partition.c545
1 files changed, 545 insertions, 0 deletions
diff --git a/drivers/misc/sgi-xp/xpc_partition.c b/drivers/misc/sgi-xp/xpc_partition.c
new file mode 100644
index 000000000..1999d0292
--- /dev/null
+++ b/drivers/misc/sgi-xp/xpc_partition.c
@@ -0,0 +1,545 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * (C) Copyright 2020 Hewlett Packard Enterprise Development LP
+ * Copyright (c) 2004-2008 Silicon Graphics, Inc. All Rights Reserved.
+ */
+
+/*
+ * Cross Partition Communication (XPC) partition support.
+ *
+ * This is the part of XPC that detects the presence/absence of
+ * other partitions. It provides a heartbeat and monitors the
+ * heartbeats of other partitions.
+ *
+ */
+
+#include <linux/device.h>
+#include <linux/hardirq.h>
+#include <linux/slab.h>
+#include "xpc.h"
+#include <asm/uv/uv_hub.h>
+
+/* XPC is exiting flag */
+int xpc_exiting;
+
+/* this partition's reserved page pointers */
+struct xpc_rsvd_page *xpc_rsvd_page;
+static unsigned long *xpc_part_nasids;
+unsigned long *xpc_mach_nasids;
+
+static int xpc_nasid_mask_nbytes; /* #of bytes in nasid mask */
+int xpc_nasid_mask_nlongs; /* #of longs in nasid mask */
+
+struct xpc_partition *xpc_partitions;
+
+/*
+ * Guarantee that the kmalloc'd memory is cacheline aligned.
+ */
+void *
+xpc_kmalloc_cacheline_aligned(size_t size, gfp_t flags, void **base)
+{
+ /* see if kmalloc will give us cachline aligned memory by default */
+ *base = kmalloc(size, flags);
+ if (*base == NULL)
+ return NULL;
+
+ if ((u64)*base == L1_CACHE_ALIGN((u64)*base))
+ return *base;
+
+ kfree(*base);
+
+ /* nope, we'll have to do it ourselves */
+ *base = kmalloc(size + L1_CACHE_BYTES, flags);
+ if (*base == NULL)
+ return NULL;
+
+ return (void *)L1_CACHE_ALIGN((u64)*base);
+}
+
+/*
+ * Given a nasid, get the physical address of the partition's reserved page
+ * for that nasid. This function returns 0 on any error.
+ */
+static unsigned long
+xpc_get_rsvd_page_pa(int nasid)
+{
+ enum xp_retval ret;
+ u64 cookie = 0;
+ unsigned long rp_pa = nasid; /* seed with nasid */
+ size_t len = 0;
+ size_t buf_len = 0;
+ void *buf = NULL;
+ void *buf_base = NULL;
+ enum xp_retval (*get_partition_rsvd_page_pa)
+ (void *, u64 *, unsigned long *, size_t *) =
+ xpc_arch_ops.get_partition_rsvd_page_pa;
+
+ while (1) {
+
+ /* !!! rp_pa will need to be _gpa on UV.
+ * ??? So do we save it into the architecture specific parts
+ * ??? of the xpc_partition structure? Do we rename this
+ * ??? function or have two versions? Rename rp_pa for UV to
+ * ??? rp_gpa?
+ */
+ ret = get_partition_rsvd_page_pa(buf, &cookie, &rp_pa, &len);
+
+ dev_dbg(xpc_part, "SAL returned with ret=%d, cookie=0x%016lx, "
+ "address=0x%016lx, len=0x%016lx\n", ret,
+ (unsigned long)cookie, rp_pa, len);
+
+ if (ret != xpNeedMoreInfo)
+ break;
+
+ if (len > buf_len) {
+ kfree(buf_base);
+ buf_len = L1_CACHE_ALIGN(len);
+ buf = xpc_kmalloc_cacheline_aligned(buf_len, GFP_KERNEL,
+ &buf_base);
+ if (buf_base == NULL) {
+ dev_err(xpc_part, "unable to kmalloc "
+ "len=0x%016lx\n", buf_len);
+ ret = xpNoMemory;
+ break;
+ }
+ }
+
+ ret = xp_remote_memcpy(xp_pa(buf), rp_pa, len);
+ if (ret != xpSuccess) {
+ dev_dbg(xpc_part, "xp_remote_memcpy failed %d\n", ret);
+ break;
+ }
+ }
+
+ kfree(buf_base);
+
+ if (ret != xpSuccess)
+ rp_pa = 0;
+
+ dev_dbg(xpc_part, "reserved page at phys address 0x%016lx\n", rp_pa);
+ return rp_pa;
+}
+
+/*
+ * Fill the partition reserved page with the information needed by
+ * other partitions to discover we are alive and establish initial
+ * communications.
+ */
+int
+xpc_setup_rsvd_page(void)
+{
+ int ret;
+ struct xpc_rsvd_page *rp;
+ unsigned long rp_pa;
+ unsigned long new_ts_jiffies;
+
+ /* get the local reserved page's address */
+
+ preempt_disable();
+ rp_pa = xpc_get_rsvd_page_pa(xp_cpu_to_nasid(smp_processor_id()));
+ preempt_enable();
+ if (rp_pa == 0) {
+ dev_err(xpc_part, "SAL failed to locate the reserved page\n");
+ return -ESRCH;
+ }
+ rp = (struct xpc_rsvd_page *)__va(xp_socket_pa(rp_pa));
+
+ 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 != xp_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 -EINVAL;
+ }
+
+ 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->SAL_nasids_size = 128;
+ }
+ xpc_nasid_mask_nbytes = rp->SAL_nasids_size;
+ xpc_nasid_mask_nlongs = BITS_TO_LONGS(rp->SAL_nasids_size *
+ BITS_PER_BYTE);
+
+ /* 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);
+
+ ret = xpc_arch_ops.setup_rsvd_page(rp);
+ if (ret != 0)
+ return ret;
+
+ /*
+ * Set timestamp of when reserved page was setup by XPC.
+ * This signifies to the remote partition that our reserved
+ * page is initialized.
+ */
+ new_ts_jiffies = jiffies;
+ if (new_ts_jiffies == 0 || new_ts_jiffies == rp->ts_jiffies)
+ new_ts_jiffies++;
+ rp->ts_jiffies = new_ts_jiffies;
+
+ xpc_rsvd_page = rp;
+ return 0;
+}
+
+void
+xpc_teardown_rsvd_page(void)
+{
+ /* a zero timestamp indicates our rsvd page is not initialized */
+ xpc_rsvd_page->ts_jiffies = 0;
+}
+
+/*
+ * Get a copy of a portion of the remote partition's rsvd page.
+ *
+ * remote_rp points to a buffer that is cacheline aligned for BTE copies and
+ * is large enough to contain a copy of their reserved page header and
+ * part_nasids mask.
+ */
+enum xp_retval
+xpc_get_remote_rp(int nasid, unsigned long *discovered_nasids,
+ struct xpc_rsvd_page *remote_rp, unsigned long *remote_rp_pa)
+{
+ int l;
+ enum xp_retval ret;
+
+ /* get the reserved page's physical address */
+
+ *remote_rp_pa = xpc_get_rsvd_page_pa(nasid);
+ if (*remote_rp_pa == 0)
+ return xpNoRsvdPageAddr;
+
+ /* pull over the reserved page header and part_nasids mask */
+ ret = xp_remote_memcpy(xp_pa(remote_rp), *remote_rp_pa,
+ XPC_RP_HEADER_SIZE + xpc_nasid_mask_nbytes);
+ if (ret != xpSuccess)
+ return ret;
+
+ if (discovered_nasids != NULL) {
+ unsigned long *remote_part_nasids =
+ XPC_RP_PART_NASIDS(remote_rp);
+
+ for (l = 0; l < xpc_nasid_mask_nlongs; l++)
+ discovered_nasids[l] |= remote_part_nasids[l];
+ }
+
+ /* zero timestamp indicates the reserved page has not been setup */
+ if (remote_rp->ts_jiffies == 0)
+ return xpRsvdPageNotSet;
+
+ if (XPC_VERSION_MAJOR(remote_rp->version) !=
+ XPC_VERSION_MAJOR(XPC_RP_VERSION)) {
+ return xpBadVersion;
+ }
+
+ /* check that both remote and local partids are valid for each side */
+ if (remote_rp->SAL_partid < 0 ||
+ remote_rp->SAL_partid >= xp_max_npartitions ||
+ remote_rp->max_npartitions <= xp_partition_id) {
+ return xpInvalidPartid;
+ }
+
+ if (remote_rp->SAL_partid == xp_partition_id)
+ return xpLocalPartid;
+
+ return xpSuccess;
+}
+
+/*
+ * See if the other side has responded to a partition deactivate request
+ * from us. Though we requested the remote partition to deactivate with regard
+ * to us, we really only need to wait for the other side to disengage from us.
+ */
+static int __xpc_partition_disengaged(struct xpc_partition *part,
+ bool from_timer)
+{
+ short partid = XPC_PARTID(part);
+ int disengaged;
+
+ disengaged = !xpc_arch_ops.partition_engaged(partid);
+ if (part->disengage_timeout) {
+ if (!disengaged) {
+ if (time_is_after_jiffies(part->disengage_timeout)) {
+ /* timelimit hasn't been reached yet */
+ return 0;
+ }
+
+ /*
+ * Other side hasn't responded to our deactivate
+ * request in a timely fashion, so assume it's dead.
+ */
+
+ dev_info(xpc_part, "deactivate request to remote "
+ "partition %d timed out\n", partid);
+ xpc_disengage_timedout = 1;
+ xpc_arch_ops.assume_partition_disengaged(partid);
+ disengaged = 1;
+ }
+ part->disengage_timeout = 0;
+
+ /* Cancel the timer function if not called from it */
+ if (!from_timer)
+ del_timer_sync(&part->disengage_timer);
+
+ DBUG_ON(part->act_state != XPC_P_AS_DEACTIVATING &&
+ part->act_state != XPC_P_AS_INACTIVE);
+ if (part->act_state != XPC_P_AS_INACTIVE)
+ xpc_wakeup_channel_mgr(part);
+
+ xpc_arch_ops.cancel_partition_deactivation_request(part);
+ }
+ return disengaged;
+}
+
+int xpc_partition_disengaged(struct xpc_partition *part)
+{
+ return __xpc_partition_disengaged(part, false);
+}
+
+int xpc_partition_disengaged_from_timer(struct xpc_partition *part)
+{
+ return __xpc_partition_disengaged(part, true);
+}
+
+/*
+ * Mark specified partition as active.
+ */
+enum xp_retval
+xpc_mark_partition_active(struct xpc_partition *part)
+{
+ unsigned long irq_flags;
+ enum xp_retval ret;
+
+ dev_dbg(xpc_part, "setting partition %d to ACTIVE\n", XPC_PARTID(part));
+
+ spin_lock_irqsave(&part->act_lock, irq_flags);
+ if (part->act_state == XPC_P_AS_ACTIVATING) {
+ part->act_state = XPC_P_AS_ACTIVE;
+ ret = xpSuccess;
+ } else {
+ DBUG_ON(part->reason == xpSuccess);
+ ret = part->reason;
+ }
+ spin_unlock_irqrestore(&part->act_lock, irq_flags);
+
+ return ret;
+}
+
+/*
+ * Start the process of deactivating the specified partition.
+ */
+void
+xpc_deactivate_partition(const int line, struct xpc_partition *part,
+ enum xp_retval reason)
+{
+ unsigned long irq_flags;
+
+ spin_lock_irqsave(&part->act_lock, irq_flags);
+
+ if (part->act_state == XPC_P_AS_INACTIVE) {
+ XPC_SET_REASON(part, reason, line);
+ spin_unlock_irqrestore(&part->act_lock, irq_flags);
+ if (reason == xpReactivating) {
+ /* we interrupt ourselves to reactivate partition */
+ xpc_arch_ops.request_partition_reactivation(part);
+ }
+ return;
+ }
+ if (part->act_state == XPC_P_AS_DEACTIVATING) {
+ if ((part->reason == xpUnloading && reason != xpUnloading) ||
+ reason == xpReactivating) {
+ XPC_SET_REASON(part, reason, line);
+ }
+ spin_unlock_irqrestore(&part->act_lock, irq_flags);
+ return;
+ }
+
+ part->act_state = XPC_P_AS_DEACTIVATING;
+ XPC_SET_REASON(part, reason, line);
+
+ spin_unlock_irqrestore(&part->act_lock, irq_flags);
+
+ /* ask remote partition to deactivate with regard to us */
+ xpc_arch_ops.request_partition_deactivation(part);
+
+ /* set a timelimit on the disengage phase of the deactivation request */
+ part->disengage_timeout = jiffies + (xpc_disengage_timelimit * HZ);
+ part->disengage_timer.expires = part->disengage_timeout;
+ add_timer(&part->disengage_timer);
+
+ dev_dbg(xpc_part, "bringing partition %d down, reason = %d\n",
+ XPC_PARTID(part), reason);
+
+ xpc_partition_going_down(part, reason);
+}
+
+/*
+ * Mark specified partition as inactive.
+ */
+void
+xpc_mark_partition_inactive(struct xpc_partition *part)
+{
+ unsigned long irq_flags;
+
+ dev_dbg(xpc_part, "setting partition %d to INACTIVE\n",
+ XPC_PARTID(part));
+
+ spin_lock_irqsave(&part->act_lock, irq_flags);
+ part->act_state = XPC_P_AS_INACTIVE;
+ spin_unlock_irqrestore(&part->act_lock, irq_flags);
+ part->remote_rp_pa = 0;
+}
+
+/*
+ * SAL has provided a partition and machine mask. The partition mask
+ * contains a bit for each even nasid in our partition. The machine
+ * mask contains a bit for each even nasid in the entire machine.
+ *
+ * Using those two bit arrays, we can determine which nasids are
+ * known in the machine. Each should also have a reserved page
+ * initialized if they are available for partitioning.
+ */
+void
+xpc_discovery(void)
+{
+ void *remote_rp_base;
+ struct xpc_rsvd_page *remote_rp;
+ unsigned long remote_rp_pa;
+ int region;
+ int region_size;
+ int max_regions;
+ int nasid;
+ unsigned long *discovered_nasids;
+ enum xp_retval ret;
+
+ remote_rp = xpc_kmalloc_cacheline_aligned(XPC_RP_HEADER_SIZE +
+ xpc_nasid_mask_nbytes,
+ GFP_KERNEL, &remote_rp_base);
+ if (remote_rp == NULL)
+ return;
+
+ discovered_nasids = kcalloc(xpc_nasid_mask_nlongs, sizeof(long),
+ GFP_KERNEL);
+ if (discovered_nasids == NULL) {
+ kfree(remote_rp_base);
+ return;
+ }
+
+ /*
+ * The term 'region' in this context refers to the minimum number of
+ * nodes that can comprise an access protection grouping. The access
+ * protection is in regards to memory, IOI and IPI.
+ */
+ region_size = xp_region_size;
+
+ if (is_uv_system())
+ max_regions = 256;
+ else {
+ max_regions = 64;
+
+ switch (region_size) {
+ case 128:
+ max_regions *= 2;
+ fallthrough;
+ case 64:
+ max_regions *= 2;
+ fallthrough;
+ case 32:
+ max_regions *= 2;
+ region_size = 16;
+ }
+ }
+
+ for (region = 0; region < max_regions; region++) {
+
+ if (xpc_exiting)
+ break;
+
+ dev_dbg(xpc_part, "searching region %d\n", region);
+
+ for (nasid = (region * region_size * 2);
+ nasid < ((region + 1) * region_size * 2); nasid += 2) {
+
+ if (xpc_exiting)
+ break;
+
+ dev_dbg(xpc_part, "checking nasid %d\n", nasid);
+
+ if (test_bit(nasid / 2, xpc_part_nasids)) {
+ dev_dbg(xpc_part, "PROM indicates Nasid %d is "
+ "part of the local partition; skipping "
+ "region\n", nasid);
+ break;
+ }
+
+ if (!(test_bit(nasid / 2, xpc_mach_nasids))) {
+ dev_dbg(xpc_part, "PROM indicates Nasid %d was "
+ "not on Numa-Link network at reset\n",
+ nasid);
+ continue;
+ }
+
+ if (test_bit(nasid / 2, discovered_nasids)) {
+ dev_dbg(xpc_part, "Nasid %d is part of a "
+ "partition which was previously "
+ "discovered\n", nasid);
+ continue;
+ }
+
+ /* pull over the rsvd page header & part_nasids mask */
+
+ ret = xpc_get_remote_rp(nasid, discovered_nasids,
+ remote_rp, &remote_rp_pa);
+ if (ret != xpSuccess) {
+ dev_dbg(xpc_part, "unable to get reserved page "
+ "from nasid %d, reason=%d\n", nasid,
+ ret);
+
+ if (ret == xpLocalPartid)
+ break;
+
+ continue;
+ }
+
+ xpc_arch_ops.request_partition_activation(remote_rp,
+ remote_rp_pa, nasid);
+ }
+ }
+
+ kfree(discovered_nasids);
+ kfree(remote_rp_base);
+}
+
+/*
+ * Given a partid, get the nasids owned by that partition from the
+ * remote partition's reserved page.
+ */
+enum xp_retval
+xpc_initiate_partid_to_nasids(short partid, void *nasid_mask)
+{
+ struct xpc_partition *part;
+ unsigned long part_nasid_pa;
+
+ part = &xpc_partitions[partid];
+ if (part->remote_rp_pa == 0)
+ return xpPartitionDown;
+
+ memset(nasid_mask, 0, xpc_nasid_mask_nbytes);
+
+ part_nasid_pa = (unsigned long)XPC_RP_PART_NASIDS(part->remote_rp_pa);
+
+ return xp_remote_memcpy(xp_pa(nasid_mask), part_nasid_pa,
+ xpc_nasid_mask_nbytes);
+}
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