| Message ID | 20220624041950.559155-21-dan.j.williams@intel.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | CXL PMEM Region Provisioning | expand |
On Thu, 23 Jun 2022 21:19:50 -0700 Dan Williams <dan.j.williams@intel.com> wrote: > The LIBNVDIMM subsystem is a platform agnostic representation of system > NVDIMM / persistent memory resources. To date, the CXL subsystem's > interaction with LIBNVDIMM has been to register an nvdimm-bridge device > and cxl_nvdimm objects to proxy CXL capabilities into existing LIBNVDIMM > subsystem mechanics. > > With regions the approach is the same. Create a new cxl_pmem_region > object to proxy CXL region details into a LIBNVDIMM definition. With > this enabling LIBNVDIMM can partition CXL persistent memory regions with > legacy namespace labels. A follow-on patch will add CXL region label and > CXL namespace label support to persist region configurations across > driver reload / system-reset events. ah. Now I see why we share ID space with NVDIMMs. Fair enough, I should have read to the end ;) > > Co-developed-by: Ben Widawsky <bwidawsk@kernel.org> > Signed-off-by: Ben Widawsky <bwidawsk@kernel.org> > Signed-off-by: Dan Williams <dan.j.williams@intel.com> End of day, so a fairly superficial review on this and I'll hopefully take a second look at one or two of the earlier patches when time allows. Jonathan ... > +static struct cxl_pmem_region *cxl_pmem_region_alloc(struct cxl_region *cxlr) > +{ > + struct cxl_pmem_region *cxlr_pmem = ERR_PTR(-ENXIO); Rarely used, so better to set it where it is. > + struct cxl_region_params *p = &cxlr->params; > + struct device *dev; > + int i; > + > + down_read(&cxl_region_rwsem); > + if (p->state != CXL_CONFIG_COMMIT) > + goto out; > + cxlr_pmem = kzalloc(struct_size(cxlr_pmem, mapping, p->nr_targets), > + GFP_KERNEL); > + if (!cxlr_pmem) { > + cxlr_pmem = ERR_PTR(-ENOMEM); > + goto out; > + } > + > + cxlr_pmem->hpa_range.start = p->res->start; > + cxlr_pmem->hpa_range.end = p->res->end; > + > + /* Snapshot the region configuration underneath the cxl_region_rwsem */ > + cxlr_pmem->nr_mappings = p->nr_targets; > + for (i = 0; i < p->nr_targets; i++) { > + struct cxl_endpoint_decoder *cxled = p->targets[i]; > + struct cxl_memdev *cxlmd = cxled_to_memdev(cxled); > + struct cxl_pmem_region_mapping *m = &cxlr_pmem->mapping[i]; > + > + m->cxlmd = cxlmd; > + get_device(&cxlmd->dev); > + m->start = cxled->dpa_res->start; > + m->size = resource_size(cxled->dpa_res); > + m->position = i; > + } > + > + dev = &cxlr_pmem->dev; > + cxlr_pmem->cxlr = cxlr; > + device_initialize(dev); > + lockdep_set_class(&dev->mutex, &cxl_pmem_region_key); > + device_set_pm_not_required(dev); > + dev->parent = &cxlr->dev; > + dev->bus = &cxl_bus_type; > + dev->type = &cxl_pmem_region_type; > +out: > + up_read(&cxl_region_rwsem); > + > + return cxlr_pmem; > +} > + > +static void cxlr_pmem_unregister(void *dev) > +{ > + device_unregister(dev); > +} > + > +/** > + * devm_cxl_add_pmem_region() - add a cxl_region to nd_region bridge > + * @host: same host as @cxlmd Run kernel-doc over these and clean all the warning sup. Parameter if cxlr not host > + * > + * Return: 0 on success negative error code on failure. > + */ > /* > * Unit test builds overrides this to __weak, find the 'strong' version > diff --git a/drivers/cxl/pmem.c b/drivers/cxl/pmem.c > index b271f6e90b91..4ba7248275ac 100644 > --- a/drivers/cxl/pmem.c > +++ b/drivers/cxl/pmem.c > @@ -7,6 +7,7 @@ > > +static int match_cxl_nvdimm(struct device *dev, void *data) > +{ > + return is_cxl_nvdimm(dev); > +} > + > +static void unregister_region(void *nd_region) Better to give this a more specific name as we have several unregister_region() functions in CXL now. > +{ > + struct cxl_nvdimm_bridge *cxl_nvb; > + struct cxl_pmem_region *cxlr_pmem; > + int i; > + > + cxlr_pmem = nd_region_provider_data(nd_region); > + cxl_nvb = cxlr_pmem->bridge; > + device_lock(&cxl_nvb->dev); > + for (i = 0; i < cxlr_pmem->nr_mappings; i++) { > + struct cxl_pmem_region_mapping *m = &cxlr_pmem->mapping[i]; > + struct cxl_nvdimm *cxl_nvd = m->cxl_nvd; > + > + if (cxl_nvd->region) { > + put_device(&cxlr_pmem->dev); > + cxl_nvd->region = NULL; > + } > + } > + device_unlock(&cxl_nvb->dev); > + > + nvdimm_region_delete(nd_region); > +} > + > + > +static int cxl_pmem_region_probe(struct device *dev) > +{ > + struct nd_mapping_desc mappings[CXL_DECODER_MAX_INTERLEAVE]; > + struct cxl_pmem_region *cxlr_pmem = to_cxl_pmem_region(dev); > + struct cxl_region *cxlr = cxlr_pmem->cxlr; > + struct cxl_pmem_region_info *info = NULL; > + struct cxl_nvdimm_bridge *cxl_nvb; > + struct nd_interleave_set *nd_set; > + struct nd_region_desc ndr_desc; > + struct cxl_nvdimm *cxl_nvd; > + struct nvdimm *nvdimm; > + struct resource *res; > + int rc = 0, i; > + > + cxl_nvb = cxl_find_nvdimm_bridge(&cxlr_pmem->mapping[0].cxlmd->dev); > + if (!cxl_nvb) { > + dev_dbg(dev, "bridge not found\n"); > + return -ENXIO; > + } > + cxlr_pmem->bridge = cxl_nvb; > + > + device_lock(&cxl_nvb->dev); > + if (!cxl_nvb->nvdimm_bus) { > + dev_dbg(dev, "nvdimm bus not found\n"); > + rc = -ENXIO; > + goto out; > + } > + > + memset(&mappings, 0, sizeof(mappings)); > + memset(&ndr_desc, 0, sizeof(ndr_desc)); > + > + res = devm_kzalloc(dev, sizeof(*res), GFP_KERNEL); > + if (!res) { > + rc = -ENOMEM; > + goto out; > + } > + > + res->name = "Persistent Memory"; > + res->start = cxlr_pmem->hpa_range.start; > + res->end = cxlr_pmem->hpa_range.end; > + res->flags = IORESOURCE_MEM; > + res->desc = IORES_DESC_PERSISTENT_MEMORY; > + > + rc = insert_resource(&iomem_resource, res); > + if (rc) > + goto out; > + > + rc = devm_add_action_or_reset(dev, cxlr_pmem_remove_resource, res); > + if (rc) > + goto out; > + > + ndr_desc.res = res; > + ndr_desc.provider_data = cxlr_pmem; > + > + ndr_desc.numa_node = memory_add_physaddr_to_nid(res->start); > + ndr_desc.target_node = phys_to_target_node(res->start); > + if (ndr_desc.target_node == NUMA_NO_NODE) { > + ndr_desc.target_node = ndr_desc.numa_node; > + dev_dbg(&cxlr->dev, "changing target node from %d to %d", > + NUMA_NO_NODE, ndr_desc.target_node); > + } > + > + nd_set = devm_kzalloc(dev, sizeof(*nd_set), GFP_KERNEL); > + if (!nd_set) { > + rc = -ENOMEM; > + goto out; > + } > + > + ndr_desc.memregion = cxlr->id; > + set_bit(ND_REGION_CXL, &ndr_desc.flags); > + set_bit(ND_REGION_PERSIST_MEMCTRL, &ndr_desc.flags); > + > + info = kmalloc_array(cxlr_pmem->nr_mappings, sizeof(*info), GFP_KERNEL); > + if (!info) > + goto out; > + > + rc = -ENODEV; Personal taste, but I'd much rather see that set in the error handlers so I can quickly see where it applies. > + for (i = 0; i < cxlr_pmem->nr_mappings; i++) { > + struct cxl_pmem_region_mapping *m = &cxlr_pmem->mapping[i]; > + struct cxl_memdev *cxlmd = m->cxlmd; > + struct cxl_dev_state *cxlds = cxlmd->cxlds; > + struct device *d; > + > + d = device_find_child(&cxlmd->dev, NULL, match_cxl_nvdimm); > + if (!d) { > + dev_dbg(dev, "[%d]: %s: no cxl_nvdimm found\n", i, > + dev_name(&cxlmd->dev)); > + goto err; > + } > + > + /* safe to drop ref now with bridge lock held */ > + put_device(d); > + > + cxl_nvd = to_cxl_nvdimm(d); > + nvdimm = dev_get_drvdata(&cxl_nvd->dev); > + if (!nvdimm) { > + dev_dbg(dev, "[%d]: %s: no nvdimm found\n", i, > + dev_name(&cxlmd->dev)); > + goto err; > + } > + cxl_nvd->region = cxlr_pmem; > + get_device(&cxlr_pmem->dev); > + m->cxl_nvd = cxl_nvd; > + mappings[i] = (struct nd_mapping_desc) { > + .nvdimm = nvdimm, > + .start = m->start, > + .size = m->size, > + .position = i, > + }; > + info[i].offset = m->start; > + info[i].serial = cxlds->serial; > + } > + ndr_desc.num_mappings = cxlr_pmem->nr_mappings; > + ndr_desc.mapping = mappings; > + > + /* > + * TODO enable CXL labels which skip the need for 'interleave-set cookie' > + */ > + nd_set->cookie1 = > + nd_fletcher64(info, sizeof(*info) * cxlr_pmem->nr_mappings, 0); > + nd_set->cookie2 = nd_set->cookie1; > + ndr_desc.nd_set = nd_set; > + > + cxlr_pmem->nd_region = > + nvdimm_pmem_region_create(cxl_nvb->nvdimm_bus, &ndr_desc); > + if (IS_ERR(cxlr_pmem->nd_region)) { > + rc = PTR_ERR(cxlr_pmem->nd_region); > + goto err; > + } else no need for else as other branch has gone flying off down to err. > + rc = devm_add_action_or_reset(dev, unregister_region, > + cxlr_pmem->nd_region); > +out: Having labels out: and err: where both are used for errors is pretty confusing naming... Perhaps you are better off just not sharing the good exit path with any of the error paths. > + device_unlock(&cxl_nvb->dev); > + put_device(&cxl_nvb->dev); > + kfree(info); Ok, so safe to do this here, but would be nice to do this in reverse order of setup with multiple labels so we can avoid paths that free things that were never created. Doesn't look like it would hurt much to move kfree(info) above the device_unlock() and only do that if we have allocated info. > + > + if (rc) > + dev_dbg(dev, "failed to create nvdimm region\n"); > + return rc; > + > +err: > + for (i--; i >= 0; i--) { > + nvdimm = mappings[i].nvdimm; > + cxl_nvd = nvdimm_provider_data(nvdimm); > + put_device(&cxl_nvd->region->dev); > + cxl_nvd->region = NULL; > + } > + goto out; > +} > +
Jonathan Cameron wrote: > On Thu, 23 Jun 2022 21:19:50 -0700 > Dan Williams <dan.j.williams@intel.com> wrote: > > > The LIBNVDIMM subsystem is a platform agnostic representation of system > > NVDIMM / persistent memory resources. To date, the CXL subsystem's > > interaction with LIBNVDIMM has been to register an nvdimm-bridge device > > and cxl_nvdimm objects to proxy CXL capabilities into existing LIBNVDIMM > > subsystem mechanics. > > > > With regions the approach is the same. Create a new cxl_pmem_region > > object to proxy CXL region details into a LIBNVDIMM definition. With > > this enabling LIBNVDIMM can partition CXL persistent memory regions with > > legacy namespace labels. A follow-on patch will add CXL region label and > > CXL namespace label support to persist region configurations across > > driver reload / system-reset events. > ah. Now I see why we share ID space with NVDIMMs. Fair enough, I should > have read to the end ;) > > > > > Co-developed-by: Ben Widawsky <bwidawsk@kernel.org> > > Signed-off-by: Ben Widawsky <bwidawsk@kernel.org> > > Signed-off-by: Dan Williams <dan.j.williams@intel.com> > > End of day, so a fairly superficial review on this and I'll hopefully > take a second look at one or two of the earlier patches when time allows. > > Jonathan > > ... > > > +static struct cxl_pmem_region *cxl_pmem_region_alloc(struct cxl_region *cxlr) > > +{ > > + struct cxl_pmem_region *cxlr_pmem = ERR_PTR(-ENXIO); > > Rarely used, so better to set it where it is. Ok. > > > + struct cxl_region_params *p = &cxlr->params; > > + struct device *dev; > > + int i; > > + > > + down_read(&cxl_region_rwsem); > > + if (p->state != CXL_CONFIG_COMMIT) > > + goto out; > > + cxlr_pmem = kzalloc(struct_size(cxlr_pmem, mapping, p->nr_targets), > > + GFP_KERNEL); > > + if (!cxlr_pmem) { > > + cxlr_pmem = ERR_PTR(-ENOMEM); > > + goto out; > > + } > > + > > + cxlr_pmem->hpa_range.start = p->res->start; > > + cxlr_pmem->hpa_range.end = p->res->end; > > + > > + /* Snapshot the region configuration underneath the cxl_region_rwsem */ > > + cxlr_pmem->nr_mappings = p->nr_targets; > > + for (i = 0; i < p->nr_targets; i++) { > > + struct cxl_endpoint_decoder *cxled = p->targets[i]; > > + struct cxl_memdev *cxlmd = cxled_to_memdev(cxled); > > + struct cxl_pmem_region_mapping *m = &cxlr_pmem->mapping[i]; > > + > > + m->cxlmd = cxlmd; > > + get_device(&cxlmd->dev); > > + m->start = cxled->dpa_res->start; > > + m->size = resource_size(cxled->dpa_res); > > + m->position = i; > > + } > > + > > + dev = &cxlr_pmem->dev; > > + cxlr_pmem->cxlr = cxlr; > > + device_initialize(dev); > > + lockdep_set_class(&dev->mutex, &cxl_pmem_region_key); > > + device_set_pm_not_required(dev); > > + dev->parent = &cxlr->dev; > > + dev->bus = &cxl_bus_type; > > + dev->type = &cxl_pmem_region_type; > > +out: > > + up_read(&cxl_region_rwsem); > > + > > + return cxlr_pmem; > > +} > > + > > +static void cxlr_pmem_unregister(void *dev) > > +{ > > + device_unregister(dev); > > +} > > + > > +/** > > + * devm_cxl_add_pmem_region() - add a cxl_region to nd_region bridge > > + * @host: same host as @cxlmd > > Run kernel-doc over these and clean all the warning sup. > Parameter if cxlr not host Fixed. > > > > + * > > + * Return: 0 on success negative error code on failure. > > + */ > > > > /* > > * Unit test builds overrides this to __weak, find the 'strong' version > > diff --git a/drivers/cxl/pmem.c b/drivers/cxl/pmem.c > > index b271f6e90b91..4ba7248275ac 100644 > > --- a/drivers/cxl/pmem.c > > +++ b/drivers/cxl/pmem.c > > @@ -7,6 +7,7 @@ > > > > > > > +static int match_cxl_nvdimm(struct device *dev, void *data) > > +{ > > + return is_cxl_nvdimm(dev); > > +} > > + > > +static void unregister_region(void *nd_region) > > Better to give this a more specific name as we have several > unregister_region() functions in CXL now. Ok, unregister_nvdimm_region() it is. > > > +{ > > + struct cxl_nvdimm_bridge *cxl_nvb; > > + struct cxl_pmem_region *cxlr_pmem; > > + int i; > > + > > + cxlr_pmem = nd_region_provider_data(nd_region); > > + cxl_nvb = cxlr_pmem->bridge; > > + device_lock(&cxl_nvb->dev); > > + for (i = 0; i < cxlr_pmem->nr_mappings; i++) { > > + struct cxl_pmem_region_mapping *m = &cxlr_pmem->mapping[i]; > > + struct cxl_nvdimm *cxl_nvd = m->cxl_nvd; > > + > > + if (cxl_nvd->region) { > > + put_device(&cxlr_pmem->dev); > > + cxl_nvd->region = NULL; > > + } > > + } > > + device_unlock(&cxl_nvb->dev); > > + > > + nvdimm_region_delete(nd_region); > > +} > > + > > > + > > +static int cxl_pmem_region_probe(struct device *dev) > > +{ > > + struct nd_mapping_desc mappings[CXL_DECODER_MAX_INTERLEAVE]; > > + struct cxl_pmem_region *cxlr_pmem = to_cxl_pmem_region(dev); > > + struct cxl_region *cxlr = cxlr_pmem->cxlr; > > + struct cxl_pmem_region_info *info = NULL; > > + struct cxl_nvdimm_bridge *cxl_nvb; > > + struct nd_interleave_set *nd_set; > > + struct nd_region_desc ndr_desc; > > + struct cxl_nvdimm *cxl_nvd; > > + struct nvdimm *nvdimm; > > + struct resource *res; > > + int rc = 0, i; > > + > > + cxl_nvb = cxl_find_nvdimm_bridge(&cxlr_pmem->mapping[0].cxlmd->dev); > > + if (!cxl_nvb) { > > + dev_dbg(dev, "bridge not found\n"); > > + return -ENXIO; > > + } > > + cxlr_pmem->bridge = cxl_nvb; > > + > > + device_lock(&cxl_nvb->dev); > > + if (!cxl_nvb->nvdimm_bus) { > > + dev_dbg(dev, "nvdimm bus not found\n"); > > + rc = -ENXIO; > > + goto out; > > + } > > + > > + memset(&mappings, 0, sizeof(mappings)); > > + memset(&ndr_desc, 0, sizeof(ndr_desc)); > > + > > + res = devm_kzalloc(dev, sizeof(*res), GFP_KERNEL); > > + if (!res) { > > + rc = -ENOMEM; > > + goto out; > > + } > > + > > + res->name = "Persistent Memory"; > > + res->start = cxlr_pmem->hpa_range.start; > > + res->end = cxlr_pmem->hpa_range.end; > > + res->flags = IORESOURCE_MEM; > > + res->desc = IORES_DESC_PERSISTENT_MEMORY; > > + > > + rc = insert_resource(&iomem_resource, res); > > + if (rc) > > + goto out; > > + > > + rc = devm_add_action_or_reset(dev, cxlr_pmem_remove_resource, res); > > + if (rc) > > + goto out; > > + > > + ndr_desc.res = res; > > + ndr_desc.provider_data = cxlr_pmem; > > + > > + ndr_desc.numa_node = memory_add_physaddr_to_nid(res->start); > > + ndr_desc.target_node = phys_to_target_node(res->start); > > + if (ndr_desc.target_node == NUMA_NO_NODE) { > > + ndr_desc.target_node = ndr_desc.numa_node; > > + dev_dbg(&cxlr->dev, "changing target node from %d to %d", > > + NUMA_NO_NODE, ndr_desc.target_node); > > + } > > + > > + nd_set = devm_kzalloc(dev, sizeof(*nd_set), GFP_KERNEL); > > + if (!nd_set) { > > + rc = -ENOMEM; > > + goto out; > > + } > > + > > + ndr_desc.memregion = cxlr->id; > > + set_bit(ND_REGION_CXL, &ndr_desc.flags); > > + set_bit(ND_REGION_PERSIST_MEMCTRL, &ndr_desc.flags); > > + > > + info = kmalloc_array(cxlr_pmem->nr_mappings, sizeof(*info), GFP_KERNEL); > > + if (!info) > > + goto out; > > + > > + rc = -ENODEV; > > Personal taste, but I'd much rather see that set in the error handlers > so I can quickly see where it applies. Ok. > > > + for (i = 0; i < cxlr_pmem->nr_mappings; i++) { > > + struct cxl_pmem_region_mapping *m = &cxlr_pmem->mapping[i]; > > + struct cxl_memdev *cxlmd = m->cxlmd; > > + struct cxl_dev_state *cxlds = cxlmd->cxlds; > > + struct device *d; > > + > > + d = device_find_child(&cxlmd->dev, NULL, match_cxl_nvdimm); > > + if (!d) { > > + dev_dbg(dev, "[%d]: %s: no cxl_nvdimm found\n", i, > > + dev_name(&cxlmd->dev)); > > + goto err; > > + } > > + > > + /* safe to drop ref now with bridge lock held */ > > + put_device(d); > > + > > + cxl_nvd = to_cxl_nvdimm(d); > > + nvdimm = dev_get_drvdata(&cxl_nvd->dev); > > + if (!nvdimm) { > > + dev_dbg(dev, "[%d]: %s: no nvdimm found\n", i, > > + dev_name(&cxlmd->dev)); > > + goto err; > > + } > > + cxl_nvd->region = cxlr_pmem; > > + get_device(&cxlr_pmem->dev); > > + m->cxl_nvd = cxl_nvd; > > + mappings[i] = (struct nd_mapping_desc) { > > + .nvdimm = nvdimm, > > + .start = m->start, > > + .size = m->size, > > + .position = i, > > + }; > > + info[i].offset = m->start; > > + info[i].serial = cxlds->serial; > > + } > > + ndr_desc.num_mappings = cxlr_pmem->nr_mappings; > > + ndr_desc.mapping = mappings; > > + > > + /* > > + * TODO enable CXL labels which skip the need for 'interleave-set cookie' > > + */ > > + nd_set->cookie1 = > > + nd_fletcher64(info, sizeof(*info) * cxlr_pmem->nr_mappings, 0); > > + nd_set->cookie2 = nd_set->cookie1; > > + ndr_desc.nd_set = nd_set; > > + > > + cxlr_pmem->nd_region = > > + nvdimm_pmem_region_create(cxl_nvb->nvdimm_bus, &ndr_desc); > > + if (IS_ERR(cxlr_pmem->nd_region)) { > > + rc = PTR_ERR(cxlr_pmem->nd_region); > > + goto err; > > + } else > > no need for else as other branch has gone flying off down to > err. Yup. > > > + rc = devm_add_action_or_reset(dev, unregister_region, > > + cxlr_pmem->nd_region); > > +out: > > Having labels out: and err: where both are used for errors is pretty > confusing naming... Perhaps you are better off just not sharing the > good exit path with any of the error paths. > Ok. > > > + device_unlock(&cxl_nvb->dev); > > + put_device(&cxl_nvb->dev); > > + kfree(info); > > Ok, so safe to do this here, but would be nice to do this > in reverse order of setup with multiple labels so we can avoid > paths that free things that were never created. Doesn't look > like it would hurt much to move kfree(info) above the device_unlock() > and only do that if we have allocated info. Ok, but no need for more labels, unconditionally free'ing info and trying to unwind the mapping references can proceed if @info is initialized to NULL and @i is initialized to 0.
diff --git a/drivers/cxl/core/core.h b/drivers/cxl/core/core.h index be5198ab8f3b..f5c5b041e8a5 100644 --- a/drivers/cxl/core/core.h +++ b/drivers/cxl/core/core.h @@ -13,6 +13,7 @@ extern struct attribute_group cxl_base_attribute_group; extern struct device_attribute dev_attr_create_pmem_region; extern struct device_attribute dev_attr_delete_region; extern struct device_attribute dev_attr_region; +extern const struct device_type cxl_pmem_region_type; extern const struct device_type cxl_region_type; void cxl_decoder_kill_region(struct cxl_endpoint_decoder *cxled); int cxl_region_init(void); @@ -23,6 +24,7 @@ void cxl_region_exit(void); */ #define CXL_REGION_ATTR(x) (&dev_attr_##x.attr) #define CXL_REGION_TYPE(x) (&cxl_region_type) +#define CXL_PMEM_REGION_TYPE(x) (&cxl_pmem_region_type) #else static inline void cxl_decoder_kill_region(struct cxl_endpoint_decoder *cxled) { @@ -36,6 +38,7 @@ static inline void cxl_region_exit(void) } #define CXL_REGION_ATTR(x) NULL #define CXL_REGION_TYPE(x) NULL +#define CXL_PMEM_REGION_TYPE(x) NULL #endif struct cxl_send_command; diff --git a/drivers/cxl/core/pmem.c b/drivers/cxl/core/pmem.c index bec7cfb54ebf..1d12a8206444 100644 --- a/drivers/cxl/core/pmem.c +++ b/drivers/cxl/core/pmem.c @@ -62,9 +62,9 @@ static int match_nvdimm_bridge(struct device *dev, void *data) return is_cxl_nvdimm_bridge(dev); } -struct cxl_nvdimm_bridge *cxl_find_nvdimm_bridge(struct cxl_nvdimm *cxl_nvd) +struct cxl_nvdimm_bridge *cxl_find_nvdimm_bridge(struct device *start) { - struct cxl_port *port = find_cxl_root(&cxl_nvd->dev); + struct cxl_port *port = find_cxl_root(start); struct device *dev; if (!port) diff --git a/drivers/cxl/core/port.c b/drivers/cxl/core/port.c index 00add9e0b192..e13cd012ed22 100644 --- a/drivers/cxl/core/port.c +++ b/drivers/cxl/core/port.c @@ -44,6 +44,8 @@ static int cxl_device_id(struct device *dev) return CXL_DEVICE_NVDIMM_BRIDGE; if (dev->type == &cxl_nvdimm_type) return CXL_DEVICE_NVDIMM; + if (dev->type == CXL_PMEM_REGION_TYPE()) + return CXL_DEVICE_PMEM_REGION; if (is_cxl_port(dev)) { if (is_cxl_root(to_cxl_port(dev))) return CXL_DEVICE_ROOT; diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c index cd1848d4c8fe..70e9baef95f7 100644 --- a/drivers/cxl/core/region.c +++ b/drivers/cxl/core/region.c @@ -1614,6 +1614,136 @@ static ssize_t delete_region_store(struct device *dev, } DEVICE_ATTR_WO(delete_region); +static void cxl_pmem_region_release(struct device *dev) +{ + struct cxl_pmem_region *cxlr_pmem = to_cxl_pmem_region(dev); + int i; + + for (i = 0; i < cxlr_pmem->nr_mappings; i++) { + struct cxl_memdev *cxlmd = cxlr_pmem->mapping[i].cxlmd; + + put_device(&cxlmd->dev); + } + + kfree(cxlr_pmem); +} + +static const struct attribute_group *cxl_pmem_region_attribute_groups[] = { + &cxl_base_attribute_group, + NULL, +}; + +const struct device_type cxl_pmem_region_type = { + .name = "cxl_pmem_region", + .release = cxl_pmem_region_release, + .groups = cxl_pmem_region_attribute_groups, +}; + +bool is_cxl_pmem_region(struct device *dev) +{ + return dev->type == &cxl_pmem_region_type; +} +EXPORT_SYMBOL_NS_GPL(is_cxl_pmem_region, CXL); + +struct cxl_pmem_region *to_cxl_pmem_region(struct device *dev) +{ + if (dev_WARN_ONCE(dev, !is_cxl_pmem_region(dev), + "not a cxl_pmem_region device\n")) + return NULL; + return container_of(dev, struct cxl_pmem_region, dev); +} +EXPORT_SYMBOL_NS_GPL(to_cxl_pmem_region, CXL); + +static struct lock_class_key cxl_pmem_region_key; + +static struct cxl_pmem_region *cxl_pmem_region_alloc(struct cxl_region *cxlr) +{ + struct cxl_pmem_region *cxlr_pmem = ERR_PTR(-ENXIO); + struct cxl_region_params *p = &cxlr->params; + struct device *dev; + int i; + + down_read(&cxl_region_rwsem); + if (p->state != CXL_CONFIG_COMMIT) + goto out; + cxlr_pmem = kzalloc(struct_size(cxlr_pmem, mapping, p->nr_targets), + GFP_KERNEL); + if (!cxlr_pmem) { + cxlr_pmem = ERR_PTR(-ENOMEM); + goto out; + } + + cxlr_pmem->hpa_range.start = p->res->start; + cxlr_pmem->hpa_range.end = p->res->end; + + /* Snapshot the region configuration underneath the cxl_region_rwsem */ + cxlr_pmem->nr_mappings = p->nr_targets; + for (i = 0; i < p->nr_targets; i++) { + struct cxl_endpoint_decoder *cxled = p->targets[i]; + struct cxl_memdev *cxlmd = cxled_to_memdev(cxled); + struct cxl_pmem_region_mapping *m = &cxlr_pmem->mapping[i]; + + m->cxlmd = cxlmd; + get_device(&cxlmd->dev); + m->start = cxled->dpa_res->start; + m->size = resource_size(cxled->dpa_res); + m->position = i; + } + + dev = &cxlr_pmem->dev; + cxlr_pmem->cxlr = cxlr; + device_initialize(dev); + lockdep_set_class(&dev->mutex, &cxl_pmem_region_key); + device_set_pm_not_required(dev); + dev->parent = &cxlr->dev; + dev->bus = &cxl_bus_type; + dev->type = &cxl_pmem_region_type; +out: + up_read(&cxl_region_rwsem); + + return cxlr_pmem; +} + +static void cxlr_pmem_unregister(void *dev) +{ + device_unregister(dev); +} + +/** + * devm_cxl_add_pmem_region() - add a cxl_region to nd_region bridge + * @host: same host as @cxlmd + * + * Return: 0 on success negative error code on failure. + */ +static int devm_cxl_add_pmem_region(struct cxl_region *cxlr) +{ + struct cxl_pmem_region *cxlr_pmem; + struct device *dev; + int rc; + + cxlr_pmem = cxl_pmem_region_alloc(cxlr); + if (IS_ERR(cxlr_pmem)) + return PTR_ERR(cxlr_pmem); + + dev = &cxlr_pmem->dev; + rc = dev_set_name(dev, "pmem_region%d", cxlr->id); + if (rc) + goto err; + + rc = device_add(dev); + if (rc) + goto err; + + dev_dbg(&cxlr->dev, "%s: register %s\n", dev_name(dev->parent), + dev_name(dev)); + + return devm_add_action_or_reset(&cxlr->dev, cxlr_pmem_unregister, dev); + +err: + put_device(dev); + return rc; +} + static int cxl_region_probe(struct device *dev) { struct cxl_region *cxlr = to_cxl_region(dev); @@ -1637,7 +1767,14 @@ static int cxl_region_probe(struct device *dev) */ up_read(&cxl_region_rwsem); - return rc; + switch (cxlr->mode) { + case CXL_DECODER_PMEM: + return devm_cxl_add_pmem_region(cxlr); + default: + dev_dbg(&cxlr->dev, "unsupported region mode: %d\n", + cxlr->mode); + return -ENXIO; + } } static struct cxl_driver cxl_region_driver = { diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h index 95f486bc1b41..bf878509bed4 100644 --- a/drivers/cxl/cxl.h +++ b/drivers/cxl/cxl.h @@ -412,6 +412,25 @@ struct cxl_nvdimm { struct device dev; struct cxl_memdev *cxlmd; struct cxl_nvdimm_bridge *bridge; + struct cxl_pmem_region *region; +}; + +struct cxl_pmem_region_mapping { + struct cxl_memdev *cxlmd; + struct cxl_nvdimm *cxl_nvd; + u64 start; + u64 size; + int position; +}; + +struct cxl_pmem_region { + struct device dev; + struct cxl_region *cxlr; + struct nd_region *nd_region; + struct cxl_nvdimm_bridge *bridge; + struct range hpa_range; + int nr_mappings; + struct cxl_pmem_region_mapping mapping[]; }; /** @@ -587,6 +606,7 @@ void cxl_driver_unregister(struct cxl_driver *cxl_drv); #define CXL_DEVICE_ROOT 4 #define CXL_DEVICE_MEMORY_EXPANDER 5 #define CXL_DEVICE_REGION 6 +#define CXL_DEVICE_PMEM_REGION 7 #define MODULE_ALIAS_CXL(type) MODULE_ALIAS("cxl:t" __stringify(type) "*") #define CXL_MODALIAS_FMT "cxl:t%d" @@ -598,7 +618,21 @@ struct cxl_nvdimm *to_cxl_nvdimm(struct device *dev); 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_nvdimm *cxl_nvd); +struct cxl_nvdimm_bridge *cxl_find_nvdimm_bridge(struct device *dev); + +#ifdef CONFIG_CXL_REGION +bool is_cxl_pmem_region(struct device *dev); +struct cxl_pmem_region *to_cxl_pmem_region(struct device *dev); +#else +static inline bool is_cxl_pmem_region(struct device *dev) +{ + return false; +} +static inline struct cxl_pmem_region *to_cxl_pmem_region(struct device *dev) +{ + return NULL; +} +#endif /* * Unit test builds overrides this to __weak, find the 'strong' version diff --git a/drivers/cxl/pmem.c b/drivers/cxl/pmem.c index b271f6e90b91..4ba7248275ac 100644 --- a/drivers/cxl/pmem.c +++ b/drivers/cxl/pmem.c @@ -7,6 +7,7 @@ #include <linux/ndctl.h> #include <linux/async.h> #include <linux/slab.h> +#include <linux/nd.h> #include "cxlmem.h" #include "cxl.h" @@ -27,6 +28,19 @@ static void clear_exclusive(void *cxlds) static void unregister_nvdimm(void *nvdimm) { struct cxl_nvdimm *cxl_nvd = nvdimm_provider_data(nvdimm); + struct cxl_nvdimm_bridge *cxl_nvb = cxl_nvd->bridge; + struct cxl_pmem_region *cxlr_pmem; + + device_lock(&cxl_nvb->dev); + cxlr_pmem = cxl_nvd->region; + dev_set_drvdata(&cxl_nvd->dev, NULL); + cxl_nvd->region = NULL; + device_unlock(&cxl_nvb->dev); + + if (cxlr_pmem) { + device_release_driver(&cxlr_pmem->dev); + put_device(&cxlr_pmem->dev); + } nvdimm_delete(nvdimm); cxl_nvd->bridge = NULL; @@ -42,7 +56,7 @@ static int cxl_nvdimm_probe(struct device *dev) struct nvdimm *nvdimm; int rc; - cxl_nvb = cxl_find_nvdimm_bridge(cxl_nvd); + cxl_nvb = cxl_find_nvdimm_bridge(dev); if (!cxl_nvb) return -ENXIO; @@ -223,6 +237,21 @@ static int cxl_nvdimm_release_driver(struct device *dev, void *cxl_nvb) return 0; } +static int cxl_pmem_region_release_driver(struct device *dev, void *cxl_nvb) +{ + struct cxl_pmem_region *cxlr_pmem; + + if (!is_cxl_pmem_region(dev)) + return 0; + + cxlr_pmem = to_cxl_pmem_region(dev); + if (cxlr_pmem->bridge != cxl_nvb) + return 0; + + device_release_driver(dev); + return 0; +} + static void offline_nvdimm_bus(struct cxl_nvdimm_bridge *cxl_nvb, struct nvdimm_bus *nvdimm_bus) { @@ -234,6 +263,8 @@ static void offline_nvdimm_bus(struct cxl_nvdimm_bridge *cxl_nvb, * nvdimm_bus_unregister() rips the nvdimm objects out from * underneath them. */ + bus_for_each_dev(&cxl_bus_type, NULL, cxl_nvb, + cxl_pmem_region_release_driver); bus_for_each_dev(&cxl_bus_type, NULL, cxl_nvb, cxl_nvdimm_release_driver); nvdimm_bus_unregister(nvdimm_bus); @@ -328,6 +359,200 @@ static struct cxl_driver cxl_nvdimm_bridge_driver = { .id = CXL_DEVICE_NVDIMM_BRIDGE, }; +static int match_cxl_nvdimm(struct device *dev, void *data) +{ + return is_cxl_nvdimm(dev); +} + +static void unregister_region(void *nd_region) +{ + struct cxl_nvdimm_bridge *cxl_nvb; + struct cxl_pmem_region *cxlr_pmem; + int i; + + cxlr_pmem = nd_region_provider_data(nd_region); + cxl_nvb = cxlr_pmem->bridge; + device_lock(&cxl_nvb->dev); + for (i = 0; i < cxlr_pmem->nr_mappings; i++) { + struct cxl_pmem_region_mapping *m = &cxlr_pmem->mapping[i]; + struct cxl_nvdimm *cxl_nvd = m->cxl_nvd; + + if (cxl_nvd->region) { + put_device(&cxlr_pmem->dev); + cxl_nvd->region = NULL; + } + } + device_unlock(&cxl_nvb->dev); + + nvdimm_region_delete(nd_region); +} + +static void cxlr_pmem_remove_resource(void *res) +{ + remove_resource(res); +} + +struct cxl_pmem_region_info { + u64 offset; + u64 serial; +}; + +static int cxl_pmem_region_probe(struct device *dev) +{ + struct nd_mapping_desc mappings[CXL_DECODER_MAX_INTERLEAVE]; + struct cxl_pmem_region *cxlr_pmem = to_cxl_pmem_region(dev); + struct cxl_region *cxlr = cxlr_pmem->cxlr; + struct cxl_pmem_region_info *info = NULL; + struct cxl_nvdimm_bridge *cxl_nvb; + struct nd_interleave_set *nd_set; + struct nd_region_desc ndr_desc; + struct cxl_nvdimm *cxl_nvd; + struct nvdimm *nvdimm; + struct resource *res; + int rc = 0, i; + + cxl_nvb = cxl_find_nvdimm_bridge(&cxlr_pmem->mapping[0].cxlmd->dev); + if (!cxl_nvb) { + dev_dbg(dev, "bridge not found\n"); + return -ENXIO; + } + cxlr_pmem->bridge = cxl_nvb; + + device_lock(&cxl_nvb->dev); + if (!cxl_nvb->nvdimm_bus) { + dev_dbg(dev, "nvdimm bus not found\n"); + rc = -ENXIO; + goto out; + } + + memset(&mappings, 0, sizeof(mappings)); + memset(&ndr_desc, 0, sizeof(ndr_desc)); + + res = devm_kzalloc(dev, sizeof(*res), GFP_KERNEL); + if (!res) { + rc = -ENOMEM; + goto out; + } + + res->name = "Persistent Memory"; + res->start = cxlr_pmem->hpa_range.start; + res->end = cxlr_pmem->hpa_range.end; + res->flags = IORESOURCE_MEM; + res->desc = IORES_DESC_PERSISTENT_MEMORY; + + rc = insert_resource(&iomem_resource, res); + if (rc) + goto out; + + rc = devm_add_action_or_reset(dev, cxlr_pmem_remove_resource, res); + if (rc) + goto out; + + ndr_desc.res = res; + ndr_desc.provider_data = cxlr_pmem; + + ndr_desc.numa_node = memory_add_physaddr_to_nid(res->start); + ndr_desc.target_node = phys_to_target_node(res->start); + if (ndr_desc.target_node == NUMA_NO_NODE) { + ndr_desc.target_node = ndr_desc.numa_node; + dev_dbg(&cxlr->dev, "changing target node from %d to %d", + NUMA_NO_NODE, ndr_desc.target_node); + } + + nd_set = devm_kzalloc(dev, sizeof(*nd_set), GFP_KERNEL); + if (!nd_set) { + rc = -ENOMEM; + goto out; + } + + ndr_desc.memregion = cxlr->id; + set_bit(ND_REGION_CXL, &ndr_desc.flags); + set_bit(ND_REGION_PERSIST_MEMCTRL, &ndr_desc.flags); + + info = kmalloc_array(cxlr_pmem->nr_mappings, sizeof(*info), GFP_KERNEL); + if (!info) + goto out; + + rc = -ENODEV; + for (i = 0; i < cxlr_pmem->nr_mappings; i++) { + struct cxl_pmem_region_mapping *m = &cxlr_pmem->mapping[i]; + struct cxl_memdev *cxlmd = m->cxlmd; + struct cxl_dev_state *cxlds = cxlmd->cxlds; + struct device *d; + + d = device_find_child(&cxlmd->dev, NULL, match_cxl_nvdimm); + if (!d) { + dev_dbg(dev, "[%d]: %s: no cxl_nvdimm found\n", i, + dev_name(&cxlmd->dev)); + goto err; + } + + /* safe to drop ref now with bridge lock held */ + put_device(d); + + cxl_nvd = to_cxl_nvdimm(d); + nvdimm = dev_get_drvdata(&cxl_nvd->dev); + if (!nvdimm) { + dev_dbg(dev, "[%d]: %s: no nvdimm found\n", i, + dev_name(&cxlmd->dev)); + goto err; + } + cxl_nvd->region = cxlr_pmem; + get_device(&cxlr_pmem->dev); + m->cxl_nvd = cxl_nvd; + mappings[i] = (struct nd_mapping_desc) { + .nvdimm = nvdimm, + .start = m->start, + .size = m->size, + .position = i, + }; + info[i].offset = m->start; + info[i].serial = cxlds->serial; + } + ndr_desc.num_mappings = cxlr_pmem->nr_mappings; + ndr_desc.mapping = mappings; + + /* + * TODO enable CXL labels which skip the need for 'interleave-set cookie' + */ + nd_set->cookie1 = + nd_fletcher64(info, sizeof(*info) * cxlr_pmem->nr_mappings, 0); + nd_set->cookie2 = nd_set->cookie1; + ndr_desc.nd_set = nd_set; + + cxlr_pmem->nd_region = + nvdimm_pmem_region_create(cxl_nvb->nvdimm_bus, &ndr_desc); + if (IS_ERR(cxlr_pmem->nd_region)) { + rc = PTR_ERR(cxlr_pmem->nd_region); + goto err; + } else + rc = devm_add_action_or_reset(dev, unregister_region, + cxlr_pmem->nd_region); +out: + device_unlock(&cxl_nvb->dev); + put_device(&cxl_nvb->dev); + kfree(info); + + if (rc) + dev_dbg(dev, "failed to create nvdimm region\n"); + return rc; + +err: + for (i--; i >= 0; i--) { + nvdimm = mappings[i].nvdimm; + cxl_nvd = nvdimm_provider_data(nvdimm); + put_device(&cxl_nvd->region->dev); + cxl_nvd->region = NULL; + } + goto out; +} + +static struct cxl_driver cxl_pmem_region_driver = { + .name = "cxl_pmem_region", + .probe = cxl_pmem_region_probe, + .id = CXL_DEVICE_PMEM_REGION, +}; + /* * Return all bridges to the CXL_NVB_NEW state to invalidate any * ->state_work referring to the now destroyed cxl_pmem_wq. @@ -372,8 +597,14 @@ static __init int cxl_pmem_init(void) if (rc) goto err_nvdimm; + rc = cxl_driver_register(&cxl_pmem_region_driver); + if (rc) + goto err_region; + return 0; +err_region: + cxl_driver_unregister(&cxl_nvdimm_driver); err_nvdimm: cxl_driver_unregister(&cxl_nvdimm_bridge_driver); err_bridge: @@ -383,6 +614,7 @@ static __init int cxl_pmem_init(void) static __exit void cxl_pmem_exit(void) { + cxl_driver_unregister(&cxl_pmem_region_driver); cxl_driver_unregister(&cxl_nvdimm_driver); cxl_driver_unregister(&cxl_nvdimm_bridge_driver); destroy_cxl_pmem_wq(); @@ -394,3 +626,4 @@ module_exit(cxl_pmem_exit); MODULE_IMPORT_NS(CXL); MODULE_ALIAS_CXL(CXL_DEVICE_NVDIMM_BRIDGE); MODULE_ALIAS_CXL(CXL_DEVICE_NVDIMM); +MODULE_ALIAS_CXL(CXL_DEVICE_PMEM_REGION); diff --git a/drivers/nvdimm/region_devs.c b/drivers/nvdimm/region_devs.c index d976260eca7a..473a71bbd9c9 100644 --- a/drivers/nvdimm/region_devs.c +++ b/drivers/nvdimm/region_devs.c @@ -133,7 +133,8 @@ static void nd_region_release(struct device *dev) put_device(&nvdimm->dev); } free_percpu(nd_region->lane); - memregion_free(nd_region->id); + if (!test_bit(ND_REGION_CXL, &nd_region->flags)) + memregion_free(nd_region->id); kfree(nd_region); } @@ -982,9 +983,14 @@ static struct nd_region *nd_region_create(struct nvdimm_bus *nvdimm_bus, if (!nd_region) return NULL; - nd_region->id = memregion_alloc(GFP_KERNEL); - if (nd_region->id < 0) - goto err_id; + /* CXL pre-assigns memregion ids before creating nvdimm regions */ + if (test_bit(ND_REGION_CXL, &ndr_desc->flags)) { + nd_region->id = ndr_desc->memregion; + } else { + nd_region->id = memregion_alloc(GFP_KERNEL); + if (nd_region->id < 0) + goto err_id; + } nd_region->lane = alloc_percpu(struct nd_percpu_lane); if (!nd_region->lane) @@ -1043,9 +1049,10 @@ static struct nd_region *nd_region_create(struct nvdimm_bus *nvdimm_bus, return nd_region; - err_percpu: - memregion_free(nd_region->id); - err_id: +err_percpu: + if (!test_bit(ND_REGION_CXL, &ndr_desc->flags)) + memregion_free(nd_region->id); +err_id: kfree(nd_region); return NULL; } @@ -1068,6 +1075,13 @@ struct nd_region *nvdimm_volatile_region_create(struct nvdimm_bus *nvdimm_bus, } EXPORT_SYMBOL_GPL(nvdimm_volatile_region_create); +void nvdimm_region_delete(struct nd_region *nd_region) +{ + if (nd_region) + nd_device_unregister(&nd_region->dev, ND_SYNC); +} +EXPORT_SYMBOL_GPL(nvdimm_region_delete); + int nvdimm_flush(struct nd_region *nd_region, struct bio *bio) { int rc = 0; diff --git a/include/linux/libnvdimm.h b/include/linux/libnvdimm.h index 0d61e07b6827..c74acfa1a3fe 100644 --- a/include/linux/libnvdimm.h +++ b/include/linux/libnvdimm.h @@ -59,6 +59,9 @@ enum { /* Platform provides asynchronous flush mechanism */ ND_REGION_ASYNC = 3, + /* Region was created by CXL subsystem */ + ND_REGION_CXL = 4, + /* mark newly adjusted resources as requiring a label update */ DPA_RESOURCE_ADJUSTED = 1 << 0, }; @@ -122,6 +125,7 @@ struct nd_region_desc { int numa_node; int target_node; unsigned long flags; + int memregion; struct device_node *of_node; int (*flush)(struct nd_region *nd_region, struct bio *bio); }; @@ -259,6 +263,7 @@ static inline struct nvdimm *nvdimm_create(struct nvdimm_bus *nvdimm_bus, cmd_mask, num_flush, flush_wpq, NULL, NULL, NULL); } void nvdimm_delete(struct nvdimm *nvdimm); +void nvdimm_region_delete(struct nd_region *nd_region); const struct nd_cmd_desc *nd_cmd_dimm_desc(int cmd); const struct nd_cmd_desc *nd_cmd_bus_desc(int cmd);