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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /drivers/misc/sgi-xp/xpc_partition.c
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.zip
Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski: "Core: - Add dedicated kmem_cache for typical/small skb->head, avoid having to access struct page at kfree time, and improve memory use. - Introduce sysctl to set default RPS configuration for new netdevs. - Define Netlink protocol specification format which can be used to describe messages used by each family and auto-generate parsers. Add tools for generating kernel data structures and uAPI headers. - Expose all net/core sysctls inside netns. - Remove 4s sleep in netpoll if carrier is instantly detected on boot. - Add configurable limit of MDB entries per port, and port-vlan. - Continue populating drop reasons throughout the stack. - Retire a handful of legacy Qdiscs and classifiers. Protocols: - Support IPv4 big TCP (TSO frames larger than 64kB). - Add IP_LOCAL_PORT_RANGE socket option, to control local port range on socket by socket basis. - Track and report in procfs number of MPTCP sockets used. - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path manager. - IPv6: don't check net.ipv6.route.max_size and rely on garbage collection to free memory (similarly to IPv4). - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986). - ICMP: add per-rate limit counters. - Add support for user scanning requests in ieee802154. - Remove static WEP support. - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate reporting. - WiFi 7 EHT channel puncturing support (client & AP). BPF: - Add a rbtree data structure following the "next-gen data structure" precedent set by recently added linked list, that is, by using kfunc + kptr instead of adding a new BPF map type. - Expose XDP hints via kfuncs with initial support for RX hash and timestamp metadata. - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better support decap on GRE tunnel devices not operating in collect metadata. - Improve x86 JIT's codegen for PROBE_MEM runtime error checks. - Remove the need for trace_printk_lock for bpf_trace_printk and bpf_trace_vprintk helpers. - Extend libbpf's bpf_tracing.h support for tracing arguments of kprobes/uprobes and syscall as a special case. - Significantly reduce the search time for module symbols by livepatch and BPF. - Enable cpumasks to be used as kptrs, which is useful for tracing programs tracking which tasks end up running on which CPUs in different time intervals. - Add support for BPF trampoline on s390x and riscv64. - Add capability to export the XDP features supported by the NIC. - Add __bpf_kfunc tag for marking kernel functions as kfuncs. - Add cgroup.memory=nobpf kernel parameter option to disable BPF memory accounting for container environments. Netfilter: - Remove the CLUSTERIP target. It has been marked as obsolete for years, and we still have WARN splats wrt races of the out-of-band /proc interface installed by this target. - Add 'destroy' commands to nf_tables. They are identical to the existing 'delete' commands, but do not return an error if the referenced object (set, chain, rule...) did not exist. Driver API: - Improve cpumask_local_spread() locality to help NICs set the right IRQ affinity on AMD platforms. - Separate C22 and C45 MDIO bus transactions more clearly. - Introduce new DCB table to control DSCP rewrite on egress. - Support configuration of Physical Layer Collision Avoidance (PLCA) Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of shared medium Ethernet. - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing preemption of low priority frames by high priority frames. - Add support for controlling MACSec offload using netlink SET. - Rework devlink instance refcounts to allow registration and de-registration under the instance lock. Split the code into multiple files, drop some of the unnecessarily granular locks and factor out common parts of netlink operation handling. - Add TX frame aggregation parameters (for USB drivers). - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning messages with notifications for debug. - Allow offloading of UDP NEW connections via act_ct. - Add support for per action HW stats in TC. - Support hardware miss to TC action (continue processing in SW from a specific point in the action chain). - Warn if old Wireless Extension user space interface is used with modern cfg80211/mac80211 drivers. Do not support Wireless Extensions for Wi-Fi 7 devices at all. Everyone should switch to using nl80211 interface instead. - Improve the CAN bit timing configuration. Use extack to return error messages directly to user space, update the SJW handling, including the definition of a new default value that will benefit CAN-FD controllers, by increasing their oscillator tolerance. New hardware / drivers: - Ethernet: - nVidia BlueField-3 support (control traffic driver) - Ethernet support for imx93 SoCs - Motorcomm yt8531 gigabit Ethernet PHY - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA) - Microchip LAN8841 PHY (incl. cable diagnostics and PTP) - Amlogic gxl MDIO mux - WiFi: - RealTek RTL8188EU (rtl8xxxu) - Qualcomm Wi-Fi 7 devices (ath12k) - CAN: - Renesas R-Car V4H Drivers: - Bluetooth: - Set Per Platform Antenna Gain (PPAG) for Intel controllers. - Ethernet NICs: - Intel (1G, igc): - support TSN / Qbv / packet scheduling features of i226 model - Intel (100G, ice): - use GNSS subsystem instead of TTY - multi-buffer XDP support - extend support for GPIO pins to E823 devices - nVidia/Mellanox: - update the shared buffer configuration on PFC commands - implement PTP adjphase function for HW offset control - TC support for Geneve and GRE with VF tunnel offload - more efficient crypto key management method - multi-port eswitch support - Netronome/Corigine: - add DCB IEEE support - support IPsec offloading for NFP3800 - Freescale/NXP (enetc): - support XDP_REDIRECT for XDP non-linear buffers - improve reconfig, avoid link flap and waiting for idle - support MAC Merge layer - Other NICs: - sfc/ef100: add basic devlink support for ef100 - ionic: rx_push mode operation (writing descriptors via MMIO) - bnxt: use the auxiliary bus abstraction for RDMA - r8169: disable ASPM and reset bus in case of tx timeout - cpsw: support QSGMII mode for J721e CPSW9G - cpts: support pulse-per-second output - ngbe: add an mdio bus driver - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing - r8152: handle devices with FW with NCM support - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation - virtio-net: support multi buffer XDP - virtio/vsock: replace virtio_vsock_pkt with sk_buff - tsnep: XDP support - Ethernet high-speed switches: - nVidia/Mellanox (mlxsw): - add support for latency TLV (in FW control messages) - Microchip (sparx5): - separate explicit and implicit traffic forwarding rules, make the implicit rules always active - add support for egress DSCP rewrite - IS0 VCAP support (Ingress Classification) - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS etc.) - ES2 VCAP support (Egress Access Control) - support for Per-Stream Filtering and Policing (802.1Q, 8.6.5.1) - Ethernet embedded switches: - Marvell (mv88e6xxx): - add MAB (port auth) offload support - enable PTP receive for mv88e6390 - NXP (ocelot): - support MAC Merge layer - support for the the vsc7512 internal copper phys - Microchip: - lan9303: convert to PHYLINK - lan966x: support TC flower filter statistics - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x - lan937x: support Credit Based Shaper configuration - ksz9477: support Energy Efficient Ethernet - other: - qca8k: convert to regmap read/write API, use bulk operations - rswitch: Improve TX timestamp accuracy - Intel WiFi (iwlwifi): - EHT (Wi-Fi 7) rate reporting - STEP equalizer support: transfer some STEP (connection to radio on platforms with integrated wifi) related parameters from the BIOS to the firmware. - Qualcomm 802.11ax WiFi (ath11k): - IPQ5018 support - Fine Timing Measurement (FTM) responder role support - channel 177 support - MediaTek WiFi (mt76): - per-PHY LED support - mt7996: EHT (Wi-Fi 7) support - Wireless Ethernet Dispatch (WED) reset support - switch to using page pool allocator - RealTek WiFi (rtw89): - support new version of Bluetooth co-existance - Mobile: - rmnet: support TX aggregation" * tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits) page_pool: add a comment explaining the fragment counter usage net: ethtool: fix __ethtool_dev_mm_supported() implementation ethtool: pse-pd: Fix double word in comments xsk: add linux/vmalloc.h to xsk.c sefltests: netdevsim: wait for devlink instance after netns removal selftest: fib_tests: Always cleanup before exit net/mlx5e: Align IPsec ASO result memory to be as required by hardware net/mlx5e: TC, Set CT miss to the specific ct action instance net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG net/mlx5: Refactor tc miss handling to a single function net/mlx5: Kconfig: Make tc offload depend on tc skb extension net/sched: flower: Support hardware miss to tc action net/sched: flower: Move filter handle initialization earlier net/sched: cls_api: Support hardware miss to tc action net/sched: Rename user cookie and act cookie sfc: fix builds without CONFIG_RTC_LIB sfc: clean up some inconsistent indentings net/mlx4_en: Introduce flexible array to silence overflow warning net: lan966x: Fix possible deadlock inside PTP net/ulp: Remove redundant ->clone() test in inet_clone_ulp(). ...
Diffstat (limited to 'drivers/misc/sgi-xp/xpc_partition.c')
-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);
+}