Merge tag 'cxl-for-5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl

Pull cxl updates from Dan Williams:
 "More preparation and plumbing work in the CXL subsystem.

  From an end user perspective the highlight here is lighting up the CXL
  Persistent Memory related commands (label read / write) with the
  generic ioctl() front-end in LIBNVDIMM.

  Otherwise, the ability to instantiate new persistent and volatile
  memory regions is still on track for v5.17.

  Summary:

   - Fix support for platforms that do not enumerate every ACPI0016 (CXL
     Host Bridge) in the CHBS (ACPI Host Bridge Structure).

   - Introduce a common pci_find_dvsec_capability() helper, clean up
     open coded implementations in various drivers.

   - Add 'cxl_test' for regression testing CXL subsystem ABIs.
     'cxl_test' is a module built from tools/testing/cxl/ that mocks up
     a CXL topology to augment the nascent support for emulation of CXL
     devices in QEMU.

   - Convert libnvdimm to use the uuid API.

   - Complete the definition of CXL namespace labels in libnvdimm.

   - Tunnel libnvdimm label operations from nd_ioctl() back to the CXL
     mailbox driver. Enable 'ndctl {read,write}-labels' for CXL.

   - Continue to sort and refactor functionality into distinct driver
     and core-infrastructure buckets. For example, mailbox handling is
     now a generic core capability consumed by the PCI and cxl_test
     drivers"

* tag 'cxl-for-5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl: (34 commits)
  ocxl: Use pci core's DVSEC functionality
  cxl/pci: Use pci core's DVSEC functionality
  PCI: Add pci_find_dvsec_capability to find designated VSEC
  cxl/pci: Split cxl_pci_setup_regs()
  cxl/pci: Add @base to cxl_register_map
  cxl/pci: Make more use of cxl_register_map
  cxl/pci: Remove pci request/release regions
  cxl/pci: Fix NULL vs ERR_PTR confusion
  cxl/pci: Remove dev_dbg for unknown register blocks
  cxl/pci: Convert register block identifiers to an enum
  cxl/acpi: Do not fail cxl_acpi_probe() based on a missing CHBS
  cxl/pci: Disambiguate cxl_pci further from cxl_mem
  Documentation/cxl: Add bus internal docs
  cxl/core: Split decoder setup into alloc + add
  tools/testing/cxl: Introduce a mock memory device + driver
  cxl/mbox: Move command definitions to common location
  cxl/bus: Populate the target list at decoder create
  tools/testing/cxl: Introduce a mocked-up CXL port hierarchy
  cxl/pmem: Add support for multiple nvdimm-bridge objects
  cxl/pmem: Translate NVDIMM label commands to CXL label commands
  ...

1 files changed, 37 insertions, 2 deletions

diff --git a/drivers/cxl/core/pmem.c b/drivers/cxl/core/pmem.c
index d24570f5b8ba..5032f4c1c69d 100644
--- a/drivers/cxl/core/pmem.c
+++ b/drivers/cxl/core/pmem.c
@@ -2,6 +2,7 @@
 /* Copyright(c) 2020 Intel Corporation. */
 #include <linux/device.h>
 #include <linux/slab.h>
+#include <linux/idr.h>
 #include <cxlmem.h>
 #include <cxl.h>
 #include "core.h"
@@ -20,10 +21,13 @@
  * operations, for example, namespace label access commands.
  */
 
+static DEFINE_IDA(cxl_nvdimm_bridge_ida);
+
 static void cxl_nvdimm_bridge_release(struct device *dev)
 {
 	struct cxl_nvdimm_bridge *cxl_nvb = to_cxl_nvdimm_bridge(dev);
 
+	ida_free(&cxl_nvdimm_bridge_ida, cxl_nvb->id);
 	kfree(cxl_nvb);
 }
 
@@ -47,16 +51,38 @@ struct cxl_nvdimm_bridge *to_cxl_nvdimm_bridge(struct device *dev)
 }
 EXPORT_SYMBOL_GPL(to_cxl_nvdimm_bridge);
 
+__mock int match_nvdimm_bridge(struct device *dev, const void *data)
+{
+	return dev->type == &cxl_nvdimm_bridge_type;
+}
+
+struct cxl_nvdimm_bridge *cxl_find_nvdimm_bridge(struct cxl_nvdimm *cxl_nvd)
+{
+	struct device *dev;
+
+	dev = bus_find_device(&cxl_bus_type, NULL, cxl_nvd, match_nvdimm_bridge);
+	if (!dev)
+		return NULL;
+	return to_cxl_nvdimm_bridge(dev);
+}
+EXPORT_SYMBOL_GPL(cxl_find_nvdimm_bridge);
+
 static struct cxl_nvdimm_bridge *
 cxl_nvdimm_bridge_alloc(struct cxl_port *port)
 {
 	struct cxl_nvdimm_bridge *cxl_nvb;
 	struct device *dev;
+	int rc;
 
 	cxl_nvb = kzalloc(sizeof(*cxl_nvb), GFP_KERNEL);
 	if (!cxl_nvb)
 		return ERR_PTR(-ENOMEM);
 
+	rc = ida_alloc(&cxl_nvdimm_bridge_ida, GFP_KERNEL);
+	if (rc < 0)
+		goto err;
+	cxl_nvb->id = rc;
+
 	dev = &cxl_nvb->dev;
 	cxl_nvb->port = port;
 	cxl_nvb->state = CXL_NVB_NEW;
@@ -67,6 +93,10 @@ cxl_nvdimm_bridge_alloc(struct cxl_port *port)
 	dev->type = &cxl_nvdimm_bridge_type;
 
 	return cxl_nvb;
+
+err:
+	kfree(cxl_nvb);
+	return ERR_PTR(rc);
 }
 
 static void unregister_nvb(void *_cxl_nvb)
@@ -119,7 +149,7 @@ struct cxl_nvdimm_bridge *devm_cxl_add_nvdimm_bridge(struct device *host,
 		return cxl_nvb;
 
 	dev = &cxl_nvb->dev;
-	rc = dev_set_name(dev, "nvdimm-bridge");
+	rc = dev_set_name(dev, "nvdimm-bridge%d", cxl_nvb->id);
 	if (rc)
 		goto err;
 
@@ -192,6 +222,11 @@ static struct cxl_nvdimm *cxl_nvdimm_alloc(struct cxl_memdev *cxlmd)
 	return cxl_nvd;
 }
 
+static void cxl_nvd_unregister(void *dev)
+{
+	device_unregister(dev);
+}
+
 /**
  * devm_cxl_add_nvdimm() - add a bridge between a cxl_memdev and an nvdimm
  * @host: same host as @cxlmd
@@ -221,7 +256,7 @@ int devm_cxl_add_nvdimm(struct device *host, struct cxl_memdev *cxlmd)
 	dev_dbg(host, "%s: register %s\n", dev_name(dev->parent),
 		dev_name(dev));
 
-	return devm_add_action_or_reset(host, unregister_cxl_dev, dev);
+	return devm_add_action_or_reset(host, cxl_nvd_unregister, dev);
 
 err:
 	put_device(dev);