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-rw-r--r--drivers/acpi/numa/hmat.c878
1 files changed, 878 insertions, 0 deletions
diff --git a/drivers/acpi/numa/hmat.c b/drivers/acpi/numa/hmat.c
new file mode 100644
index 000000000..26453a945
--- /dev/null
+++ b/drivers/acpi/numa/hmat.c
@@ -0,0 +1,878 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2019, Intel Corporation.
+ *
+ * Heterogeneous Memory Attributes Table (HMAT) representation
+ *
+ * This program parses and reports the platform's HMAT tables, and registers
+ * the applicable attributes with the node's interfaces.
+ */
+
+#define pr_fmt(fmt) "acpi/hmat: " fmt
+#define dev_fmt(fmt) "acpi/hmat: " fmt
+
+#include <linux/acpi.h>
+#include <linux/bitops.h>
+#include <linux/device.h>
+#include <linux/init.h>
+#include <linux/list.h>
+#include <linux/mm.h>
+#include <linux/platform_device.h>
+#include <linux/list_sort.h>
+#include <linux/memregion.h>
+#include <linux/memory.h>
+#include <linux/mutex.h>
+#include <linux/node.h>
+#include <linux/sysfs.h>
+#include <linux/dax.h>
+
+static u8 hmat_revision;
+static int hmat_disable __initdata;
+
+void __init disable_hmat(void)
+{
+ hmat_disable = 1;
+}
+
+static LIST_HEAD(targets);
+static LIST_HEAD(initiators);
+static LIST_HEAD(localities);
+
+static DEFINE_MUTEX(target_lock);
+
+/*
+ * The defined enum order is used to prioritize attributes to break ties when
+ * selecting the best performing node.
+ */
+enum locality_types {
+ WRITE_LATENCY,
+ READ_LATENCY,
+ WRITE_BANDWIDTH,
+ READ_BANDWIDTH,
+};
+
+static struct memory_locality *localities_types[4];
+
+struct target_cache {
+ struct list_head node;
+ struct node_cache_attrs cache_attrs;
+};
+
+struct memory_target {
+ struct list_head node;
+ unsigned int memory_pxm;
+ unsigned int processor_pxm;
+ struct resource memregions;
+ struct node_hmem_attrs hmem_attrs[2];
+ struct list_head caches;
+ struct node_cache_attrs cache_attrs;
+ bool registered;
+};
+
+struct memory_initiator {
+ struct list_head node;
+ unsigned int processor_pxm;
+ bool has_cpu;
+};
+
+struct memory_locality {
+ struct list_head node;
+ struct acpi_hmat_locality *hmat_loc;
+};
+
+static struct memory_initiator *find_mem_initiator(unsigned int cpu_pxm)
+{
+ struct memory_initiator *initiator;
+
+ list_for_each_entry(initiator, &initiators, node)
+ if (initiator->processor_pxm == cpu_pxm)
+ return initiator;
+ return NULL;
+}
+
+static struct memory_target *find_mem_target(unsigned int mem_pxm)
+{
+ struct memory_target *target;
+
+ list_for_each_entry(target, &targets, node)
+ if (target->memory_pxm == mem_pxm)
+ return target;
+ return NULL;
+}
+
+static __init void alloc_memory_initiator(unsigned int cpu_pxm)
+{
+ struct memory_initiator *initiator;
+
+ if (pxm_to_node(cpu_pxm) == NUMA_NO_NODE)
+ return;
+
+ initiator = find_mem_initiator(cpu_pxm);
+ if (initiator)
+ return;
+
+ initiator = kzalloc(sizeof(*initiator), GFP_KERNEL);
+ if (!initiator)
+ return;
+
+ initiator->processor_pxm = cpu_pxm;
+ initiator->has_cpu = node_state(pxm_to_node(cpu_pxm), N_CPU);
+ list_add_tail(&initiator->node, &initiators);
+}
+
+static __init void alloc_memory_target(unsigned int mem_pxm,
+ resource_size_t start, resource_size_t len)
+{
+ struct memory_target *target;
+
+ target = find_mem_target(mem_pxm);
+ if (!target) {
+ target = kzalloc(sizeof(*target), GFP_KERNEL);
+ if (!target)
+ return;
+ target->memory_pxm = mem_pxm;
+ target->processor_pxm = PXM_INVAL;
+ target->memregions = (struct resource) {
+ .name = "ACPI mem",
+ .start = 0,
+ .end = -1,
+ .flags = IORESOURCE_MEM,
+ };
+ list_add_tail(&target->node, &targets);
+ INIT_LIST_HEAD(&target->caches);
+ }
+
+ /*
+ * There are potentially multiple ranges per PXM, so record each
+ * in the per-target memregions resource tree.
+ */
+ if (!__request_region(&target->memregions, start, len, "memory target",
+ IORESOURCE_MEM))
+ pr_warn("failed to reserve %#llx - %#llx in pxm: %d\n",
+ start, start + len, mem_pxm);
+}
+
+static __init const char *hmat_data_type(u8 type)
+{
+ switch (type) {
+ case ACPI_HMAT_ACCESS_LATENCY:
+ return "Access Latency";
+ case ACPI_HMAT_READ_LATENCY:
+ return "Read Latency";
+ case ACPI_HMAT_WRITE_LATENCY:
+ return "Write Latency";
+ case ACPI_HMAT_ACCESS_BANDWIDTH:
+ return "Access Bandwidth";
+ case ACPI_HMAT_READ_BANDWIDTH:
+ return "Read Bandwidth";
+ case ACPI_HMAT_WRITE_BANDWIDTH:
+ return "Write Bandwidth";
+ default:
+ return "Reserved";
+ }
+}
+
+static __init const char *hmat_data_type_suffix(u8 type)
+{
+ switch (type) {
+ case ACPI_HMAT_ACCESS_LATENCY:
+ case ACPI_HMAT_READ_LATENCY:
+ case ACPI_HMAT_WRITE_LATENCY:
+ return " nsec";
+ case ACPI_HMAT_ACCESS_BANDWIDTH:
+ case ACPI_HMAT_READ_BANDWIDTH:
+ case ACPI_HMAT_WRITE_BANDWIDTH:
+ return " MB/s";
+ default:
+ return "";
+ }
+}
+
+static u32 hmat_normalize(u16 entry, u64 base, u8 type)
+{
+ u32 value;
+
+ /*
+ * Check for invalid and overflow values
+ */
+ if (entry == 0xffff || !entry)
+ return 0;
+ else if (base > (UINT_MAX / (entry)))
+ return 0;
+
+ /*
+ * Divide by the base unit for version 1, convert latency from
+ * picosenonds to nanoseconds if revision 2.
+ */
+ value = entry * base;
+ if (hmat_revision == 1) {
+ if (value < 10)
+ return 0;
+ value = DIV_ROUND_UP(value, 10);
+ } else if (hmat_revision == 2) {
+ switch (type) {
+ case ACPI_HMAT_ACCESS_LATENCY:
+ case ACPI_HMAT_READ_LATENCY:
+ case ACPI_HMAT_WRITE_LATENCY:
+ value = DIV_ROUND_UP(value, 1000);
+ break;
+ default:
+ break;
+ }
+ }
+ return value;
+}
+
+static void hmat_update_target_access(struct memory_target *target,
+ u8 type, u32 value, int access)
+{
+ switch (type) {
+ case ACPI_HMAT_ACCESS_LATENCY:
+ target->hmem_attrs[access].read_latency = value;
+ target->hmem_attrs[access].write_latency = value;
+ break;
+ case ACPI_HMAT_READ_LATENCY:
+ target->hmem_attrs[access].read_latency = value;
+ break;
+ case ACPI_HMAT_WRITE_LATENCY:
+ target->hmem_attrs[access].write_latency = value;
+ break;
+ case ACPI_HMAT_ACCESS_BANDWIDTH:
+ target->hmem_attrs[access].read_bandwidth = value;
+ target->hmem_attrs[access].write_bandwidth = value;
+ break;
+ case ACPI_HMAT_READ_BANDWIDTH:
+ target->hmem_attrs[access].read_bandwidth = value;
+ break;
+ case ACPI_HMAT_WRITE_BANDWIDTH:
+ target->hmem_attrs[access].write_bandwidth = value;
+ break;
+ default:
+ break;
+ }
+}
+
+static __init void hmat_add_locality(struct acpi_hmat_locality *hmat_loc)
+{
+ struct memory_locality *loc;
+
+ loc = kzalloc(sizeof(*loc), GFP_KERNEL);
+ if (!loc) {
+ pr_notice_once("Failed to allocate HMAT locality\n");
+ return;
+ }
+
+ loc->hmat_loc = hmat_loc;
+ list_add_tail(&loc->node, &localities);
+
+ switch (hmat_loc->data_type) {
+ case ACPI_HMAT_ACCESS_LATENCY:
+ localities_types[READ_LATENCY] = loc;
+ localities_types[WRITE_LATENCY] = loc;
+ break;
+ case ACPI_HMAT_READ_LATENCY:
+ localities_types[READ_LATENCY] = loc;
+ break;
+ case ACPI_HMAT_WRITE_LATENCY:
+ localities_types[WRITE_LATENCY] = loc;
+ break;
+ case ACPI_HMAT_ACCESS_BANDWIDTH:
+ localities_types[READ_BANDWIDTH] = loc;
+ localities_types[WRITE_BANDWIDTH] = loc;
+ break;
+ case ACPI_HMAT_READ_BANDWIDTH:
+ localities_types[READ_BANDWIDTH] = loc;
+ break;
+ case ACPI_HMAT_WRITE_BANDWIDTH:
+ localities_types[WRITE_BANDWIDTH] = loc;
+ break;
+ default:
+ break;
+ }
+}
+
+static __init int hmat_parse_locality(union acpi_subtable_headers *header,
+ const unsigned long end)
+{
+ struct acpi_hmat_locality *hmat_loc = (void *)header;
+ struct memory_target *target;
+ unsigned int init, targ, total_size, ipds, tpds;
+ u32 *inits, *targs, value;
+ u16 *entries;
+ u8 type, mem_hier;
+
+ if (hmat_loc->header.length < sizeof(*hmat_loc)) {
+ pr_notice("HMAT: Unexpected locality header length: %u\n",
+ hmat_loc->header.length);
+ return -EINVAL;
+ }
+
+ type = hmat_loc->data_type;
+ mem_hier = hmat_loc->flags & ACPI_HMAT_MEMORY_HIERARCHY;
+ ipds = hmat_loc->number_of_initiator_Pds;
+ tpds = hmat_loc->number_of_target_Pds;
+ total_size = sizeof(*hmat_loc) + sizeof(*entries) * ipds * tpds +
+ sizeof(*inits) * ipds + sizeof(*targs) * tpds;
+ if (hmat_loc->header.length < total_size) {
+ pr_notice("HMAT: Unexpected locality header length:%u, minimum required:%u\n",
+ hmat_loc->header.length, total_size);
+ return -EINVAL;
+ }
+
+ pr_info("HMAT: Locality: Flags:%02x Type:%s Initiator Domains:%u Target Domains:%u Base:%lld\n",
+ hmat_loc->flags, hmat_data_type(type), ipds, tpds,
+ hmat_loc->entry_base_unit);
+
+ inits = (u32 *)(hmat_loc + 1);
+ targs = inits + ipds;
+ entries = (u16 *)(targs + tpds);
+ for (init = 0; init < ipds; init++) {
+ alloc_memory_initiator(inits[init]);
+ for (targ = 0; targ < tpds; targ++) {
+ value = hmat_normalize(entries[init * tpds + targ],
+ hmat_loc->entry_base_unit,
+ type);
+ pr_info(" Initiator-Target[%u-%u]:%u%s\n",
+ inits[init], targs[targ], value,
+ hmat_data_type_suffix(type));
+
+ if (mem_hier == ACPI_HMAT_MEMORY) {
+ target = find_mem_target(targs[targ]);
+ if (target && target->processor_pxm == inits[init]) {
+ hmat_update_target_access(target, type, value, 0);
+ /* If the node has a CPU, update access 1 */
+ if (node_state(pxm_to_node(inits[init]), N_CPU))
+ hmat_update_target_access(target, type, value, 1);
+ }
+ }
+ }
+ }
+
+ if (mem_hier == ACPI_HMAT_MEMORY)
+ hmat_add_locality(hmat_loc);
+
+ return 0;
+}
+
+static __init int hmat_parse_cache(union acpi_subtable_headers *header,
+ const unsigned long end)
+{
+ struct acpi_hmat_cache *cache = (void *)header;
+ struct memory_target *target;
+ struct target_cache *tcache;
+ u32 attrs;
+
+ if (cache->header.length < sizeof(*cache)) {
+ pr_notice("HMAT: Unexpected cache header length: %u\n",
+ cache->header.length);
+ return -EINVAL;
+ }
+
+ attrs = cache->cache_attributes;
+ pr_info("HMAT: Cache: Domain:%u Size:%llu Attrs:%08x SMBIOS Handles:%d\n",
+ cache->memory_PD, cache->cache_size, attrs,
+ cache->number_of_SMBIOShandles);
+
+ target = find_mem_target(cache->memory_PD);
+ if (!target)
+ return 0;
+
+ tcache = kzalloc(sizeof(*tcache), GFP_KERNEL);
+ if (!tcache) {
+ pr_notice_once("Failed to allocate HMAT cache info\n");
+ return 0;
+ }
+
+ tcache->cache_attrs.size = cache->cache_size;
+ tcache->cache_attrs.level = (attrs & ACPI_HMAT_CACHE_LEVEL) >> 4;
+ tcache->cache_attrs.line_size = (attrs & ACPI_HMAT_CACHE_LINE_SIZE) >> 16;
+
+ switch ((attrs & ACPI_HMAT_CACHE_ASSOCIATIVITY) >> 8) {
+ case ACPI_HMAT_CA_DIRECT_MAPPED:
+ tcache->cache_attrs.indexing = NODE_CACHE_DIRECT_MAP;
+ break;
+ case ACPI_HMAT_CA_COMPLEX_CACHE_INDEXING:
+ tcache->cache_attrs.indexing = NODE_CACHE_INDEXED;
+ break;
+ case ACPI_HMAT_CA_NONE:
+ default:
+ tcache->cache_attrs.indexing = NODE_CACHE_OTHER;
+ break;
+ }
+
+ switch ((attrs & ACPI_HMAT_WRITE_POLICY) >> 12) {
+ case ACPI_HMAT_CP_WB:
+ tcache->cache_attrs.write_policy = NODE_CACHE_WRITE_BACK;
+ break;
+ case ACPI_HMAT_CP_WT:
+ tcache->cache_attrs.write_policy = NODE_CACHE_WRITE_THROUGH;
+ break;
+ case ACPI_HMAT_CP_NONE:
+ default:
+ tcache->cache_attrs.write_policy = NODE_CACHE_WRITE_OTHER;
+ break;
+ }
+ list_add_tail(&tcache->node, &target->caches);
+
+ return 0;
+}
+
+static int __init hmat_parse_proximity_domain(union acpi_subtable_headers *header,
+ const unsigned long end)
+{
+ struct acpi_hmat_proximity_domain *p = (void *)header;
+ struct memory_target *target = NULL;
+
+ if (p->header.length != sizeof(*p)) {
+ pr_notice("HMAT: Unexpected address range header length: %u\n",
+ p->header.length);
+ return -EINVAL;
+ }
+
+ if (hmat_revision == 1)
+ pr_info("HMAT: Memory (%#llx length %#llx) Flags:%04x Processor Domain:%u Memory Domain:%u\n",
+ p->reserved3, p->reserved4, p->flags, p->processor_PD,
+ p->memory_PD);
+ else
+ pr_info("HMAT: Memory Flags:%04x Processor Domain:%u Memory Domain:%u\n",
+ p->flags, p->processor_PD, p->memory_PD);
+
+ if ((hmat_revision == 1 && p->flags & ACPI_HMAT_MEMORY_PD_VALID) ||
+ hmat_revision > 1) {
+ target = find_mem_target(p->memory_PD);
+ if (!target) {
+ pr_debug("HMAT: Memory Domain missing from SRAT\n");
+ return -EINVAL;
+ }
+ }
+ if (target && p->flags & ACPI_HMAT_PROCESSOR_PD_VALID) {
+ int p_node = pxm_to_node(p->processor_PD);
+
+ if (p_node == NUMA_NO_NODE) {
+ pr_debug("HMAT: Invalid Processor Domain\n");
+ return -EINVAL;
+ }
+ target->processor_pxm = p->processor_PD;
+ }
+
+ return 0;
+}
+
+static int __init hmat_parse_subtable(union acpi_subtable_headers *header,
+ const unsigned long end)
+{
+ struct acpi_hmat_structure *hdr = (void *)header;
+
+ if (!hdr)
+ return -EINVAL;
+
+ switch (hdr->type) {
+ case ACPI_HMAT_TYPE_PROXIMITY:
+ return hmat_parse_proximity_domain(header, end);
+ case ACPI_HMAT_TYPE_LOCALITY:
+ return hmat_parse_locality(header, end);
+ case ACPI_HMAT_TYPE_CACHE:
+ return hmat_parse_cache(header, end);
+ default:
+ return -EINVAL;
+ }
+}
+
+static __init int srat_parse_mem_affinity(union acpi_subtable_headers *header,
+ const unsigned long end)
+{
+ struct acpi_srat_mem_affinity *ma = (void *)header;
+
+ if (!ma)
+ return -EINVAL;
+ if (!(ma->flags & ACPI_SRAT_MEM_ENABLED))
+ return 0;
+ alloc_memory_target(ma->proximity_domain, ma->base_address, ma->length);
+ return 0;
+}
+
+static u32 hmat_initiator_perf(struct memory_target *target,
+ struct memory_initiator *initiator,
+ struct acpi_hmat_locality *hmat_loc)
+{
+ unsigned int ipds, tpds, i, idx = 0, tdx = 0;
+ u32 *inits, *targs;
+ u16 *entries;
+
+ ipds = hmat_loc->number_of_initiator_Pds;
+ tpds = hmat_loc->number_of_target_Pds;
+ inits = (u32 *)(hmat_loc + 1);
+ targs = inits + ipds;
+ entries = (u16 *)(targs + tpds);
+
+ for (i = 0; i < ipds; i++) {
+ if (inits[i] == initiator->processor_pxm) {
+ idx = i;
+ break;
+ }
+ }
+
+ if (i == ipds)
+ return 0;
+
+ for (i = 0; i < tpds; i++) {
+ if (targs[i] == target->memory_pxm) {
+ tdx = i;
+ break;
+ }
+ }
+ if (i == tpds)
+ return 0;
+
+ return hmat_normalize(entries[idx * tpds + tdx],
+ hmat_loc->entry_base_unit,
+ hmat_loc->data_type);
+}
+
+static bool hmat_update_best(u8 type, u32 value, u32 *best)
+{
+ bool updated = false;
+
+ if (!value)
+ return false;
+
+ switch (type) {
+ case ACPI_HMAT_ACCESS_LATENCY:
+ case ACPI_HMAT_READ_LATENCY:
+ case ACPI_HMAT_WRITE_LATENCY:
+ if (!*best || *best > value) {
+ *best = value;
+ updated = true;
+ }
+ break;
+ case ACPI_HMAT_ACCESS_BANDWIDTH:
+ case ACPI_HMAT_READ_BANDWIDTH:
+ case ACPI_HMAT_WRITE_BANDWIDTH:
+ if (!*best || *best < value) {
+ *best = value;
+ updated = true;
+ }
+ break;
+ }
+
+ return updated;
+}
+
+static int initiator_cmp(void *priv, const struct list_head *a,
+ const struct list_head *b)
+{
+ struct memory_initiator *ia;
+ struct memory_initiator *ib;
+
+ ia = list_entry(a, struct memory_initiator, node);
+ ib = list_entry(b, struct memory_initiator, node);
+
+ return ia->processor_pxm - ib->processor_pxm;
+}
+
+static int initiators_to_nodemask(unsigned long *p_nodes)
+{
+ struct memory_initiator *initiator;
+
+ if (list_empty(&initiators))
+ return -ENXIO;
+
+ list_for_each_entry(initiator, &initiators, node)
+ set_bit(initiator->processor_pxm, p_nodes);
+
+ return 0;
+}
+
+static void hmat_register_target_initiators(struct memory_target *target)
+{
+ static DECLARE_BITMAP(p_nodes, MAX_NUMNODES);
+ struct memory_initiator *initiator;
+ unsigned int mem_nid, cpu_nid;
+ struct memory_locality *loc = NULL;
+ u32 best = 0;
+ bool access0done = false;
+ int i;
+
+ mem_nid = pxm_to_node(target->memory_pxm);
+ /*
+ * If the Address Range Structure provides a local processor pxm, link
+ * only that one. Otherwise, find the best performance attributes and
+ * register all initiators that match.
+ */
+ if (target->processor_pxm != PXM_INVAL) {
+ cpu_nid = pxm_to_node(target->processor_pxm);
+ register_memory_node_under_compute_node(mem_nid, cpu_nid, 0);
+ access0done = true;
+ if (node_state(cpu_nid, N_CPU)) {
+ register_memory_node_under_compute_node(mem_nid, cpu_nid, 1);
+ return;
+ }
+ }
+
+ if (list_empty(&localities))
+ return;
+
+ /*
+ * We need the initiator list sorted so we can use bitmap_clear for
+ * previously set initiators when we find a better memory accessor.
+ * We'll also use the sorting to prime the candidate nodes with known
+ * initiators.
+ */
+ bitmap_zero(p_nodes, MAX_NUMNODES);
+ list_sort(NULL, &initiators, initiator_cmp);
+ if (initiators_to_nodemask(p_nodes) < 0)
+ return;
+
+ if (!access0done) {
+ for (i = WRITE_LATENCY; i <= READ_BANDWIDTH; i++) {
+ loc = localities_types[i];
+ if (!loc)
+ continue;
+
+ best = 0;
+ list_for_each_entry(initiator, &initiators, node) {
+ u32 value;
+
+ if (!test_bit(initiator->processor_pxm, p_nodes))
+ continue;
+
+ value = hmat_initiator_perf(target, initiator,
+ loc->hmat_loc);
+ if (hmat_update_best(loc->hmat_loc->data_type, value, &best))
+ bitmap_clear(p_nodes, 0, initiator->processor_pxm);
+ if (value != best)
+ clear_bit(initiator->processor_pxm, p_nodes);
+ }
+ if (best)
+ hmat_update_target_access(target, loc->hmat_loc->data_type,
+ best, 0);
+ }
+
+ for_each_set_bit(i, p_nodes, MAX_NUMNODES) {
+ cpu_nid = pxm_to_node(i);
+ register_memory_node_under_compute_node(mem_nid, cpu_nid, 0);
+ }
+ }
+
+ /* Access 1 ignores Generic Initiators */
+ bitmap_zero(p_nodes, MAX_NUMNODES);
+ if (initiators_to_nodemask(p_nodes) < 0)
+ return;
+
+ for (i = WRITE_LATENCY; i <= READ_BANDWIDTH; i++) {
+ loc = localities_types[i];
+ if (!loc)
+ continue;
+
+ best = 0;
+ list_for_each_entry(initiator, &initiators, node) {
+ u32 value;
+
+ if (!initiator->has_cpu) {
+ clear_bit(initiator->processor_pxm, p_nodes);
+ continue;
+ }
+ if (!test_bit(initiator->processor_pxm, p_nodes))
+ continue;
+
+ value = hmat_initiator_perf(target, initiator, loc->hmat_loc);
+ if (hmat_update_best(loc->hmat_loc->data_type, value, &best))
+ bitmap_clear(p_nodes, 0, initiator->processor_pxm);
+ if (value != best)
+ clear_bit(initiator->processor_pxm, p_nodes);
+ }
+ if (best)
+ hmat_update_target_access(target, loc->hmat_loc->data_type, best, 1);
+ }
+ for_each_set_bit(i, p_nodes, MAX_NUMNODES) {
+ cpu_nid = pxm_to_node(i);
+ register_memory_node_under_compute_node(mem_nid, cpu_nid, 1);
+ }
+}
+
+static void hmat_register_target_cache(struct memory_target *target)
+{
+ unsigned mem_nid = pxm_to_node(target->memory_pxm);
+ struct target_cache *tcache;
+
+ list_for_each_entry(tcache, &target->caches, node)
+ node_add_cache(mem_nid, &tcache->cache_attrs);
+}
+
+static void hmat_register_target_perf(struct memory_target *target, int access)
+{
+ unsigned mem_nid = pxm_to_node(target->memory_pxm);
+ node_set_perf_attrs(mem_nid, &target->hmem_attrs[access], access);
+}
+
+static void hmat_register_target_devices(struct memory_target *target)
+{
+ struct resource *res;
+
+ /*
+ * Do not bother creating devices if no driver is available to
+ * consume them.
+ */
+ if (!IS_ENABLED(CONFIG_DEV_DAX_HMEM))
+ return;
+
+ for (res = target->memregions.child; res; res = res->sibling) {
+ int target_nid = pxm_to_node(target->memory_pxm);
+
+ hmem_register_device(target_nid, res);
+ }
+}
+
+static void hmat_register_target(struct memory_target *target)
+{
+ int nid = pxm_to_node(target->memory_pxm);
+
+ /*
+ * Devices may belong to either an offline or online
+ * node, so unconditionally add them.
+ */
+ hmat_register_target_devices(target);
+
+ /*
+ * Skip offline nodes. This can happen when memory
+ * marked EFI_MEMORY_SP, "specific purpose", is applied
+ * to all the memory in a promixity domain leading to
+ * the node being marked offline / unplugged, or if
+ * memory-only "hotplug" node is offline.
+ */
+ if (nid == NUMA_NO_NODE || !node_online(nid))
+ return;
+
+ mutex_lock(&target_lock);
+ if (!target->registered) {
+ hmat_register_target_initiators(target);
+ hmat_register_target_cache(target);
+ hmat_register_target_perf(target, 0);
+ hmat_register_target_perf(target, 1);
+ target->registered = true;
+ }
+ mutex_unlock(&target_lock);
+}
+
+static void hmat_register_targets(void)
+{
+ struct memory_target *target;
+
+ list_for_each_entry(target, &targets, node)
+ hmat_register_target(target);
+}
+
+static int hmat_callback(struct notifier_block *self,
+ unsigned long action, void *arg)
+{
+ struct memory_target *target;
+ struct memory_notify *mnb = arg;
+ int pxm, nid = mnb->status_change_nid;
+
+ if (nid == NUMA_NO_NODE || action != MEM_ONLINE)
+ return NOTIFY_OK;
+
+ pxm = node_to_pxm(nid);
+ target = find_mem_target(pxm);
+ if (!target)
+ return NOTIFY_OK;
+
+ hmat_register_target(target);
+ return NOTIFY_OK;
+}
+
+static struct notifier_block hmat_callback_nb = {
+ .notifier_call = hmat_callback,
+ .priority = 2,
+};
+
+static __init void hmat_free_structures(void)
+{
+ struct memory_target *target, *tnext;
+ struct memory_locality *loc, *lnext;
+ struct memory_initiator *initiator, *inext;
+ struct target_cache *tcache, *cnext;
+
+ list_for_each_entry_safe(target, tnext, &targets, node) {
+ struct resource *res, *res_next;
+
+ list_for_each_entry_safe(tcache, cnext, &target->caches, node) {
+ list_del(&tcache->node);
+ kfree(tcache);
+ }
+
+ list_del(&target->node);
+ res = target->memregions.child;
+ while (res) {
+ res_next = res->sibling;
+ __release_region(&target->memregions, res->start,
+ resource_size(res));
+ res = res_next;
+ }
+ kfree(target);
+ }
+
+ list_for_each_entry_safe(initiator, inext, &initiators, node) {
+ list_del(&initiator->node);
+ kfree(initiator);
+ }
+
+ list_for_each_entry_safe(loc, lnext, &localities, node) {
+ list_del(&loc->node);
+ kfree(loc);
+ }
+}
+
+static __init int hmat_init(void)
+{
+ struct acpi_table_header *tbl;
+ enum acpi_hmat_type i;
+ acpi_status status;
+
+ if (srat_disabled() || hmat_disable)
+ return 0;
+
+ status = acpi_get_table(ACPI_SIG_SRAT, 0, &tbl);
+ if (ACPI_FAILURE(status))
+ return 0;
+
+ if (acpi_table_parse_entries(ACPI_SIG_SRAT,
+ sizeof(struct acpi_table_srat),
+ ACPI_SRAT_TYPE_MEMORY_AFFINITY,
+ srat_parse_mem_affinity, 0) < 0)
+ goto out_put;
+ acpi_put_table(tbl);
+
+ status = acpi_get_table(ACPI_SIG_HMAT, 0, &tbl);
+ if (ACPI_FAILURE(status))
+ goto out_put;
+
+ hmat_revision = tbl->revision;
+ switch (hmat_revision) {
+ case 1:
+ case 2:
+ break;
+ default:
+ pr_notice("Ignoring HMAT: Unknown revision:%d\n", hmat_revision);
+ goto out_put;
+ }
+
+ for (i = ACPI_HMAT_TYPE_PROXIMITY; i < ACPI_HMAT_TYPE_RESERVED; i++) {
+ if (acpi_table_parse_entries(ACPI_SIG_HMAT,
+ sizeof(struct acpi_table_hmat), i,
+ hmat_parse_subtable, 0) < 0) {
+ pr_notice("Ignoring HMAT: Invalid table");
+ goto out_put;
+ }
+ }
+ hmat_register_targets();
+
+ /* Keep the table and structures if the notifier may use them */
+ if (!register_hotmemory_notifier(&hmat_callback_nb))
+ return 0;
+out_put:
+ hmat_free_structures();
+ acpi_put_table(tbl);
+ return 0;
+}
+device_initcall(hmat_init);