LIBNVDIMM supports the creation of regions for both persistent and volatile memory ranges. The cxl_region driver is capable of handling the CXL side of region creation but will reuse LIBVDIMM for interfacing with the rest of the kernel.
TODO: CXL regions can go away. As a result the nd_region must also be torn down. TODO2: Handle mappings. LIBNVDIMM is capable of being informed about which parts of devices contribute to a region and validating whether or not the region is configured properly. To do this properly requires tracking allocations per device. Signed-off-by: Ben Widawsky <[email protected]> --- drivers/cxl/core/pmem.c | 16 +++++++++++++ drivers/cxl/cxl.h | 1 + drivers/cxl/region.c | 52 +++++++++++++++++++++++++++++++++++++++++ 3 files changed, 69 insertions(+) diff --git a/drivers/cxl/core/pmem.c b/drivers/cxl/core/pmem.c index bfcf51fbda5d..762a08c6f073 100644 --- a/drivers/cxl/core/pmem.c +++ b/drivers/cxl/core/pmem.c @@ -213,6 +213,22 @@ struct cxl_nvdimm *to_cxl_nvdimm(struct device *dev) } EXPORT_SYMBOL_NS_GPL(to_cxl_nvdimm, CXL); +static int match_cxl_nvdimm(struct device *dev, void *data) +{ + return is_cxl_nvdimm(dev); +} + +struct cxl_nvdimm *cxl_find_nvdimm(struct cxl_memdev *cxlmd) +{ + struct device *dev; + + dev = device_find_child(&cxlmd->dev, NULL, match_cxl_nvdimm); + if (!dev) + return NULL; + return to_cxl_nvdimm(dev); +} +EXPORT_SYMBOL_NS_GPL(cxl_find_nvdimm, CXL); + static struct cxl_nvdimm *cxl_nvdimm_alloc(struct cxl_memdev *cxlmd) { struct cxl_nvdimm *cxl_nvd; diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h index 6f9cabb77c08..a7b90356914d 100644 --- a/drivers/cxl/cxl.h +++ b/drivers/cxl/cxl.h @@ -434,6 +434,7 @@ bool is_cxl_nvdimm(struct device *dev); bool is_cxl_nvdimm_bridge(struct device *dev); int devm_cxl_add_nvdimm(struct device *host, struct cxl_memdev *cxlmd); struct cxl_nvdimm_bridge *cxl_find_nvdimm_bridge(struct cxl_memdev *cxlmd); +struct cxl_nvdimm *cxl_find_nvdimm(struct cxl_memdev *cxlmd); /* * Unit test builds overrides this to __weak, find the 'strong' version diff --git a/drivers/cxl/region.c b/drivers/cxl/region.c index d00305655f5a..d4a7e8d47c11 100644 --- a/drivers/cxl/region.c +++ b/drivers/cxl/region.c @@ -623,6 +623,52 @@ static int bind_region(struct cxl_region *region) return rc; } +static int connect_to_libnvdimm(struct cxl_region *region) +{ + struct nd_region_desc ndr_desc; + struct cxl_nvdimm_bridge *nvb; + struct nd_region *ndr; + int rc = 0; + + nvb = cxl_find_nvdimm_bridge(region->config.targets[0]); + device_lock(&nvb->dev); + if (!nvb->nvdimm_bus) { + rc = -ENXIO; + goto out; + } + + memset(&ndr_desc, 0, sizeof(ndr_desc)); + + ndr_desc.res = region->res; + + ndr_desc.numa_node = memory_add_physaddr_to_nid(region->res->start); + ndr_desc.target_node = phys_to_target_node(region->res->start); + if (ndr_desc.numa_node == NUMA_NO_NODE) { + ndr_desc.numa_node = + memory_add_physaddr_to_nid(region->res->start); + dev_info(®ion->dev, + "changing numa node from %d to %d for CXL region %pR", + NUMA_NO_NODE, ndr_desc.numa_node, region->res); + } + if (ndr_desc.target_node == NUMA_NO_NODE) { + ndr_desc.target_node = ndr_desc.numa_node; + dev_info(®ion->dev, + "changing target node from %d to %d for CXL region %pR", + NUMA_NO_NODE, ndr_desc.target_node, region->res); + } + + ndr = nvdimm_pmem_region_create(nvb->nvdimm_bus, &ndr_desc); + if (IS_ERR(ndr)) + rc = PTR_ERR(ndr); + else + dev_set_drvdata(®ion->dev, ndr); + +out: + device_unlock(&nvb->dev); + put_device(&nvb->dev); + return rc; +} + static void region_unregister(void *dev) { struct cxl_region *region = to_cxl_region(dev); @@ -704,6 +750,12 @@ static int cxl_region_probe(struct device *dev) return ret; } + ret = connect_to_libnvdimm(region); + if (ret) { + region_unregister(dev); + return ret; + } + region->active = true; dev_info(dev, "Bound"); -- 2.34.1
