Merge tag 'cxl-for-5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl

Pull CXL (Compute Express Link) updates from Dan Williams:
 "The highlight is initial support for CXL memory hotplug. The static
  NUMA node (ACPI SRAT Physical Address to Proximity Domain) information
  known to platform firmware is extended to support the potential
  performance-class / memory-target nodes dynamically created from
  available CXL memory device capacity.

  New unit test infrastructure is added for validating health
  information payloads.

  Fixes to module reload stress and stack usage from exposure in -next
  are included. A symbol rename and some other miscellaneous fixups are
  included as well.

  Summary:

   - Rework ACPI sub-table infrastructure to optionally be used outside
     of __init scenarios and use it for CEDT.CFMWS sub-table parsing.

   - Add support for extending num_possible_nodes by the potential
     hotplug CXL memory ranges

   - Extend tools/testing/cxl with mock memory device health information

   - Fix a module-reload workqueue race

   - Fix excessive stack-frame usage

   - Rename the driver context data structure from "cxl_mem" since that
     name collides with a proposed driver name

   - Use EXPORT_SYMBOL_NS_GPL instead of -DDEFAULT_SYMBOL_NAMESPACE at
     build time"

* tag 'cxl-for-5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl:
  cxl/core: Remove cxld_const_init in cxl_decoder_alloc()
  cxl/pmem: Fix module reload vs workqueue state
  ACPI: NUMA: Add a node and memblk for each CFMWS not in SRAT
  cxl/test: Mock acpi_table_parse_cedt()
  cxl/acpi: Convert CFMWS parsing to ACPI sub-table helpers
  ACPI: Add a context argument for table parsing handlers
  ACPI: Teach ACPI table parsing about the CEDT header format
  ACPI: Keep sub-table parsing infrastructure available for modules
  tools/testing/cxl: add mock output for the GET_HEALTH_INFO command
  cxl/memdev: Remove unused cxlmd field
  cxl/core: Convert to EXPORT_SYMBOL_NS_GPL
  cxl/memdev: Change cxl_mem to a more descriptive name
  cxl/mbox: Remove bad comment
  cxl/pmem: Fix reference counting for delayed work

1 files changed, 58 insertions, 1 deletions

diff --git a/drivers/acpi/numa/srat.c b/drivers/acpi/numa/srat.c
index 6c884f3e8332..3b818ab186be 100644
--- a/drivers/acpi/numa/srat.c
+++ b/drivers/acpi/numa/srat.c
@@ -297,6 +297,47 @@ out_err_bad_srat:
 out_err:
 	return -EINVAL;
 }
+
+static int __init acpi_parse_cfmws(union acpi_subtable_headers *header,
+				   void *arg, const unsigned long table_end)
+{
+	struct acpi_cedt_cfmws *cfmws;
+	int *fake_pxm = arg;
+	u64 start, end;
+	int node;
+
+	cfmws = (struct acpi_cedt_cfmws *)header;
+	start = cfmws->base_hpa;
+	end = cfmws->base_hpa + cfmws->window_size;
+
+	/* Skip if the SRAT already described the NUMA details for this HPA */
+	node = phys_to_target_node(start);
+	if (node != NUMA_NO_NODE)
+		return 0;
+
+	node = acpi_map_pxm_to_node(*fake_pxm);
+
+	if (node == NUMA_NO_NODE) {
+		pr_err("ACPI NUMA: Too many proximity domains while processing CFMWS.\n");
+		return -EINVAL;
+	}
+
+	if (numa_add_memblk(node, start, end) < 0) {
+		/* CXL driver must handle the NUMA_NO_NODE case */
+		pr_warn("ACPI NUMA: Failed to add memblk for CFMWS node %d [mem %#llx-%#llx]\n",
+			node, start, end);
+	}
+
+	/* Set the next available fake_pxm value */
+	(*fake_pxm)++;
+	return 0;
+}
+#else
+static int __init acpi_parse_cfmws(union acpi_subtable_headers *header,
+				   void *arg, const unsigned long table_end)
+{
+	return 0;
+}
 #endif /* defined(CONFIG_X86) || defined (CONFIG_ARM64) */
 
 static int __init acpi_parse_slit(struct acpi_table_header *table)
@@ -441,7 +482,7 @@ acpi_table_parse_srat(enum acpi_srat_type id,
 
 int __init acpi_numa_init(void)
 {
-	int cnt = 0;
+	int i, fake_pxm, cnt = 0;
 
 	if (acpi_disabled)
 		return -EINVAL;
@@ -477,6 +518,22 @@ int __init acpi_numa_init(void)
 	/* SLIT: System Locality Information Table */
 	acpi_table_parse(ACPI_SIG_SLIT, acpi_parse_slit);
 
+	/*
+	 * CXL Fixed Memory Window Structures (CFMWS) must be parsed
+	 * after the SRAT. Create NUMA Nodes for CXL memory ranges that
+	 * are defined in the CFMWS and not already defined in the SRAT.
+	 * Initialize a fake_pxm as the first available PXM to emulate.
+	 */
+
+	/* fake_pxm is the next unused PXM value after SRAT parsing */
+	for (i = 0, fake_pxm = -1; i < MAX_NUMNODES - 1; i++) {
+		if (node_to_pxm_map[i] > fake_pxm)
+			fake_pxm = node_to_pxm_map[i];
+	}
+	fake_pxm++;
+	acpi_table_parse_cedt(ACPI_CEDT_TYPE_CFMWS, acpi_parse_cfmws,
+			      &fake_pxm);
+
 	if (cnt < 0)
 		return cnt;
 	else if (!parsed_numa_memblks)