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, 59 insertions, 26 deletions

diff --git a/drivers/cxl/pmem.c b/drivers/cxl/pmem.c
index ceb2115981e5..b65a272a2d6d 100644
--- a/drivers/cxl/pmem.c
+++ b/drivers/cxl/pmem.c
@@ -19,9 +19,9 @@ static struct workqueue_struct *cxl_pmem_wq;
 
 static __read_mostly DECLARE_BITMAP(exclusive_cmds, CXL_MEM_COMMAND_ID_MAX);
 
-static void clear_exclusive(void *cxlm)
+static void clear_exclusive(void *cxlds)
 {
-	clear_exclusive_cxl_commands(cxlm, exclusive_cmds);
+	clear_exclusive_cxl_commands(cxlds, exclusive_cmds);
 }
 
 static void unregister_nvdimm(void *nvdimm)
@@ -34,7 +34,7 @@ static int cxl_nvdimm_probe(struct device *dev)
 	struct cxl_nvdimm *cxl_nvd = to_cxl_nvdimm(dev);
 	struct cxl_memdev *cxlmd = cxl_nvd->cxlmd;
 	unsigned long flags = 0, cmd_mask = 0;
-	struct cxl_mem *cxlm = cxlmd->cxlm;
+	struct cxl_dev_state *cxlds = cxlmd->cxlds;
 	struct cxl_nvdimm_bridge *cxl_nvb;
 	struct nvdimm *nvdimm;
 	int rc;
@@ -49,8 +49,8 @@ static int cxl_nvdimm_probe(struct device *dev)
 		goto out;
 	}
 
-	set_exclusive_cxl_commands(cxlm, exclusive_cmds);
-	rc = devm_add_action_or_reset(dev, clear_exclusive, cxlm);
+	set_exclusive_cxl_commands(cxlds, exclusive_cmds);
+	rc = devm_add_action_or_reset(dev, clear_exclusive, cxlds);
 	if (rc)
 		goto out;
 
@@ -80,7 +80,7 @@ static struct cxl_driver cxl_nvdimm_driver = {
 	.id = CXL_DEVICE_NVDIMM,
 };
 
-static int cxl_pmem_get_config_size(struct cxl_mem *cxlm,
+static int cxl_pmem_get_config_size(struct cxl_dev_state *cxlds,
 				    struct nd_cmd_get_config_size *cmd,
 				    unsigned int buf_len)
 {
@@ -88,14 +88,14 @@ static int cxl_pmem_get_config_size(struct cxl_mem *cxlm,
 		return -EINVAL;
 
 	*cmd = (struct nd_cmd_get_config_size) {
-		 .config_size = cxlm->lsa_size,
-		 .max_xfer = cxlm->payload_size,
+		 .config_size = cxlds->lsa_size,
+		 .max_xfer = cxlds->payload_size,
 	};
 
 	return 0;
 }
 
-static int cxl_pmem_get_config_data(struct cxl_mem *cxlm,
+static int cxl_pmem_get_config_data(struct cxl_dev_state *cxlds,
 				    struct nd_cmd_get_config_data_hdr *cmd,
 				    unsigned int buf_len)
 {
@@ -112,15 +112,14 @@ static int cxl_pmem_get_config_data(struct cxl_mem *cxlm,
 		.length = cmd->in_length,
 	};
 
-	rc = cxl_mem_mbox_send_cmd(cxlm, CXL_MBOX_OP_GET_LSA, &get_lsa,
-				   sizeof(get_lsa), cmd->out_buf,
-				   cmd->in_length);
+	rc = cxl_mbox_send_cmd(cxlds, CXL_MBOX_OP_GET_LSA, &get_lsa,
+			       sizeof(get_lsa), cmd->out_buf, cmd->in_length);
 	cmd->status = 0;
 
 	return rc;
 }
 
-static int cxl_pmem_set_config_data(struct cxl_mem *cxlm,
+static int cxl_pmem_set_config_data(struct cxl_dev_state *cxlds,
 				    struct nd_cmd_set_config_hdr *cmd,
 				    unsigned int buf_len)
 {
@@ -144,9 +143,9 @@ static int cxl_pmem_set_config_data(struct cxl_mem *cxlm,
 	};
 	memcpy(set_lsa->data, cmd->in_buf, cmd->in_length);
 
-	rc = cxl_mem_mbox_send_cmd(cxlm, CXL_MBOX_OP_SET_LSA, set_lsa,
-				   struct_size(set_lsa, data, cmd->in_length),
-				   NULL, 0);
+	rc = cxl_mbox_send_cmd(cxlds, CXL_MBOX_OP_SET_LSA, set_lsa,
+			       struct_size(set_lsa, data, cmd->in_length),
+			       NULL, 0);
 
 	/*
 	 * Set "firmware" status (4-packed bytes at the end of the input
@@ -164,18 +163,18 @@ static int cxl_pmem_nvdimm_ctl(struct nvdimm *nvdimm, unsigned int cmd,
 	struct cxl_nvdimm *cxl_nvd = nvdimm_provider_data(nvdimm);
 	unsigned long cmd_mask = nvdimm_cmd_mask(nvdimm);
 	struct cxl_memdev *cxlmd = cxl_nvd->cxlmd;
-	struct cxl_mem *cxlm = cxlmd->cxlm;
+	struct cxl_dev_state *cxlds = cxlmd->cxlds;
 
 	if (!test_bit(cmd, &cmd_mask))
 		return -ENOTTY;
 
 	switch (cmd) {
 	case ND_CMD_GET_CONFIG_SIZE:
-		return cxl_pmem_get_config_size(cxlm, buf, buf_len);
+		return cxl_pmem_get_config_size(cxlds, buf, buf_len);
 	case ND_CMD_GET_CONFIG_DATA:
-		return cxl_pmem_get_config_data(cxlm, buf, buf_len);
+		return cxl_pmem_get_config_data(cxlds, buf, buf_len);
 	case ND_CMD_SET_CONFIG_DATA:
-		return cxl_pmem_set_config_data(cxlm, buf, buf_len);
+		return cxl_pmem_set_config_data(cxlds, buf, buf_len);
 	default:
 		return -ENOTTY;
 	}
@@ -266,14 +265,24 @@ static void cxl_nvb_update_state(struct work_struct *work)
 	put_device(&cxl_nvb->dev);
 }
 
+static void cxl_nvdimm_bridge_state_work(struct cxl_nvdimm_bridge *cxl_nvb)
+{
+	/*
+	 * Take a reference that the workqueue will drop if new work
+	 * gets queued.
+	 */
+	get_device(&cxl_nvb->dev);
+	if (!queue_work(cxl_pmem_wq, &cxl_nvb->state_work))
+		put_device(&cxl_nvb->dev);
+}
+
 static void cxl_nvdimm_bridge_remove(struct device *dev)
 {
 	struct cxl_nvdimm_bridge *cxl_nvb = to_cxl_nvdimm_bridge(dev);
 
 	if (cxl_nvb->state == CXL_NVB_ONLINE)
 		cxl_nvb->state = CXL_NVB_OFFLINE;
-	if (queue_work(cxl_pmem_wq, &cxl_nvb->state_work))
-		get_device(&cxl_nvb->dev);
+	cxl_nvdimm_bridge_state_work(cxl_nvb);
 }
 
 static int cxl_nvdimm_bridge_probe(struct device *dev)
@@ -294,8 +303,7 @@ static int cxl_nvdimm_bridge_probe(struct device *dev)
 	}
 
 	cxl_nvb->state = CXL_NVB_ONLINE;
-	if (queue_work(cxl_pmem_wq, &cxl_nvb->state_work))
-		get_device(&cxl_nvb->dev);
+	cxl_nvdimm_bridge_state_work(cxl_nvb);
 
 	return 0;
 }
@@ -307,6 +315,31 @@ static struct cxl_driver cxl_nvdimm_bridge_driver = {
 	.id = CXL_DEVICE_NVDIMM_BRIDGE,
 };
 
+/*
+ * Return all bridges to the CXL_NVB_NEW state to invalidate any
+ * ->state_work referring to the now destroyed cxl_pmem_wq.
+ */
+static int cxl_nvdimm_bridge_reset(struct device *dev, void *data)
+{
+	struct cxl_nvdimm_bridge *cxl_nvb;
+
+	if (!is_cxl_nvdimm_bridge(dev))
+		return 0;
+
+	cxl_nvb = to_cxl_nvdimm_bridge(dev);
+	device_lock(dev);
+	cxl_nvb->state = CXL_NVB_NEW;
+	device_unlock(dev);
+
+	return 0;
+}
+
+static void destroy_cxl_pmem_wq(void)
+{
+	destroy_workqueue(cxl_pmem_wq);
+	bus_for_each_dev(&cxl_bus_type, NULL, NULL, cxl_nvdimm_bridge_reset);
+}
+
 static __init int cxl_pmem_init(void)
 {
 	int rc;
@@ -332,7 +365,7 @@ static __init int cxl_pmem_init(void)
 err_nvdimm:
 	cxl_driver_unregister(&cxl_nvdimm_bridge_driver);
 err_bridge:
-	destroy_workqueue(cxl_pmem_wq);
+	destroy_cxl_pmem_wq();
 	return rc;
 }
 
@@ -340,7 +373,7 @@ static __exit void cxl_pmem_exit(void)
 {
 	cxl_driver_unregister(&cxl_nvdimm_driver);
 	cxl_driver_unregister(&cxl_nvdimm_bridge_driver);
-	destroy_workqueue(cxl_pmem_wq);
+	destroy_cxl_pmem_wq();
 }
 
 MODULE_LICENSE("GPL v2");