From eaf961536e1622ad21247ac8d44acd48ba65566e Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Fri, 1 May 2015 13:11:27 -0400 Subject: libnvdimm, nfit: add interleave-set state-tracking infrastructure On platforms that have firmware support for reading/writing per-dimm label space, a portion of the dimm may be accessible via an interleave set PMEM mapping in addition to the dimm's BLK (block-data-window aperture(s)) interface. A label, stored in a "configuration data region" on the dimm, disambiguates which dimm addresses are accessed through which exclusive interface. Add infrastructure that allows the kernel to block modifications to a label in the set while any member dimm is active. Note that this is meant only for enforcing "no modifications of active labels" via the coarse ioctl command. Adding/deleting namespaces from an active interleave set is always possible via sysfs. Another aspect of tracking interleave sets is tracking their integrity when DIMMs in a set are physically re-ordered. For this purpose we generate an "interleave-set cookie" that can be recorded in a label and validated against the current configuration. It is the bus provider implementation's responsibility to calculate the interleave set cookie and attach it to a given region. Cc: Neil Brown Cc: Cc: Greg KH Cc: Robert Moore Cc: Rafael J. Wysocki Acked-by: Christoph Hellwig Acked-by: Rafael J. Wysocki Signed-off-by: Dan Williams --- drivers/acpi/nfit.c | 93 +++++++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 91 insertions(+), 2 deletions(-) (limited to 'drivers/acpi') diff --git a/drivers/acpi/nfit.c b/drivers/acpi/nfit.c index ce290748fe36..35af6f7f0abd 100644 --- a/drivers/acpi/nfit.c +++ b/drivers/acpi/nfit.c @@ -16,6 +16,7 @@ #include #include #include +#include #include "nfit.h" static bool force_enable_dimms; @@ -785,6 +786,91 @@ static const struct attribute_group *acpi_nfit_region_attribute_groups[] = { NULL, }; +/* enough info to uniquely specify an interleave set */ +struct nfit_set_info { + struct nfit_set_info_map { + u64 region_offset; + u32 serial_number; + u32 pad; + } mapping[0]; +}; + +static size_t sizeof_nfit_set_info(int num_mappings) +{ + return sizeof(struct nfit_set_info) + + num_mappings * sizeof(struct nfit_set_info_map); +} + +static int cmp_map(const void *m0, const void *m1) +{ + const struct nfit_set_info_map *map0 = m0; + const struct nfit_set_info_map *map1 = m1; + + return memcmp(&map0->region_offset, &map1->region_offset, + sizeof(u64)); +} + +/* Retrieve the nth entry referencing this spa */ +static struct acpi_nfit_memory_map *memdev_from_spa( + struct acpi_nfit_desc *acpi_desc, u16 range_index, int n) +{ + struct nfit_memdev *nfit_memdev; + + list_for_each_entry(nfit_memdev, &acpi_desc->memdevs, list) + if (nfit_memdev->memdev->range_index == range_index) + if (n-- == 0) + return nfit_memdev->memdev; + return NULL; +} + +static int acpi_nfit_init_interleave_set(struct acpi_nfit_desc *acpi_desc, + struct nd_region_desc *ndr_desc, + struct acpi_nfit_system_address *spa) +{ + int i, spa_type = nfit_spa_type(spa); + struct device *dev = acpi_desc->dev; + struct nd_interleave_set *nd_set; + u16 nr = ndr_desc->num_mappings; + struct nfit_set_info *info; + + if (spa_type == NFIT_SPA_PM || spa_type == NFIT_SPA_VOLATILE) + /* pass */; + else + return 0; + + nd_set = devm_kzalloc(dev, sizeof(*nd_set), GFP_KERNEL); + if (!nd_set) + return -ENOMEM; + + info = devm_kzalloc(dev, sizeof_nfit_set_info(nr), GFP_KERNEL); + if (!info) + return -ENOMEM; + for (i = 0; i < nr; i++) { + struct nd_mapping *nd_mapping = &ndr_desc->nd_mapping[i]; + struct nfit_set_info_map *map = &info->mapping[i]; + struct nvdimm *nvdimm = nd_mapping->nvdimm; + struct nfit_mem *nfit_mem = nvdimm_provider_data(nvdimm); + struct acpi_nfit_memory_map *memdev = memdev_from_spa(acpi_desc, + spa->range_index, i); + + if (!memdev || !nfit_mem->dcr) { + dev_err(dev, "%s: failed to find DCR\n", __func__); + return -ENODEV; + } + + map->region_offset = memdev->region_offset; + map->serial_number = nfit_mem->dcr->serial_number; + } + + sort(&info->mapping[0], nr, sizeof(struct nfit_set_info_map), + cmp_map, NULL); + nd_set->cookie = nd_fletcher64(info, sizeof_nfit_set_info(nr), 0); + ndr_desc->nd_set = nd_set; + devm_kfree(dev, info); + + return 0; +} + static int acpi_nfit_init_mapping(struct acpi_nfit_desc *acpi_desc, struct nd_mapping *nd_mapping, struct nd_region_desc *ndr_desc, struct acpi_nfit_memory_map *memdev, @@ -838,7 +924,7 @@ static int acpi_nfit_register_region(struct acpi_nfit_desc *acpi_desc, struct nd_region_desc ndr_desc; struct nvdimm_bus *nvdimm_bus; struct resource res; - int count = 0; + int count = 0, rc; if (spa->range_index == 0) { dev_dbg(acpi_desc->dev, "%s: detected invalid spa index\n", @@ -857,7 +943,6 @@ static int acpi_nfit_register_region(struct acpi_nfit_desc *acpi_desc, list_for_each_entry(nfit_memdev, &acpi_desc->memdevs, list) { struct acpi_nfit_memory_map *memdev = nfit_memdev->memdev; struct nd_mapping *nd_mapping; - int rc; if (memdev->range_index != spa->range_index) continue; @@ -875,6 +960,10 @@ static int acpi_nfit_register_region(struct acpi_nfit_desc *acpi_desc, ndr_desc.nd_mapping = nd_mappings; ndr_desc.num_mappings = count; + rc = acpi_nfit_init_interleave_set(acpi_desc, &ndr_desc, spa); + if (rc) + return rc; + nvdimm_bus = acpi_desc->nvdimm_bus; if (nfit_spa_type(spa) == NFIT_SPA_PM) { if (!nvdimm_pmem_region_create(nvdimm_bus, &ndr_desc)) -- cgit v1.2.3