From eaf961536e1622ad21247ac8d44acd48ba65566e Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Fri, 1 May 2015 13:11:27 -0400 Subject: [PATCH] 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 +++++++++++++++++++++++++++++++++++- drivers/nvdimm/bus.c | 59 ++++++++++++++++++++++- drivers/nvdimm/core.c | 17 +++++++ drivers/nvdimm/dimm_devs.c | 19 +++++++- drivers/nvdimm/nd-core.h | 10 +++- drivers/nvdimm/nd.h | 1 + drivers/nvdimm/region_devs.c | 69 ++++++++++++++++++++++++++ include/linux/libnvdimm.h | 6 +++ 8 files changed, 269 insertions(+), 5 deletions(-) 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)) diff --git a/drivers/nvdimm/bus.c b/drivers/nvdimm/bus.c index 4b77665a6cc8..ffb43cada625 100644 --- a/drivers/nvdimm/bus.c +++ b/drivers/nvdimm/bus.c @@ -68,6 +68,21 @@ static struct module *to_bus_provider(struct device *dev) return NULL; } +static void nvdimm_bus_probe_start(struct nvdimm_bus *nvdimm_bus) +{ + nvdimm_bus_lock(&nvdimm_bus->dev); + nvdimm_bus->probe_active++; + nvdimm_bus_unlock(&nvdimm_bus->dev); +} + +static void nvdimm_bus_probe_end(struct nvdimm_bus *nvdimm_bus) +{ + nvdimm_bus_lock(&nvdimm_bus->dev); + if (--nvdimm_bus->probe_active == 0) + wake_up(&nvdimm_bus->probe_wait); + nvdimm_bus_unlock(&nvdimm_bus->dev); +} + static int nvdimm_bus_probe(struct device *dev) { struct nd_device_driver *nd_drv = to_nd_device_driver(dev->driver); @@ -78,7 +93,12 @@ static int nvdimm_bus_probe(struct device *dev) if (!try_module_get(provider)) return -ENXIO; + nvdimm_bus_probe_start(nvdimm_bus); rc = nd_drv->probe(dev); + if (rc == 0) + nd_region_probe_success(nvdimm_bus, dev); + nvdimm_bus_probe_end(nvdimm_bus); + dev_dbg(&nvdimm_bus->dev, "%s.probe(%s) = %d\n", dev->driver->name, dev_name(dev), rc); if (rc != 0) @@ -94,6 +114,8 @@ static int nvdimm_bus_remove(struct device *dev) int rc; rc = nd_drv->remove(dev); + nd_region_disable(nvdimm_bus, dev); + dev_dbg(&nvdimm_bus->dev, "%s.remove(%s) = %d\n", dev->driver->name, dev_name(dev), rc); module_put(provider); @@ -359,6 +381,34 @@ u32 nd_cmd_out_size(struct nvdimm *nvdimm, int cmd, } EXPORT_SYMBOL_GPL(nd_cmd_out_size); +static void wait_nvdimm_bus_probe_idle(struct nvdimm_bus *nvdimm_bus) +{ + do { + if (nvdimm_bus->probe_active == 0) + break; + nvdimm_bus_unlock(&nvdimm_bus->dev); + wait_event(nvdimm_bus->probe_wait, + nvdimm_bus->probe_active == 0); + nvdimm_bus_lock(&nvdimm_bus->dev); + } while (true); +} + +/* set_config requires an idle interleave set */ +static int nd_cmd_clear_to_send(struct nvdimm *nvdimm, unsigned int cmd) +{ + struct nvdimm_bus *nvdimm_bus; + + if (!nvdimm || cmd != ND_CMD_SET_CONFIG_DATA) + return 0; + + nvdimm_bus = walk_to_nvdimm_bus(&nvdimm->dev); + wait_nvdimm_bus_probe_idle(nvdimm_bus); + + if (atomic_read(&nvdimm->busy)) + return -EBUSY; + return 0; +} + static int __nd_ioctl(struct nvdimm_bus *nvdimm_bus, struct nvdimm *nvdimm, int read_only, unsigned int ioctl_cmd, unsigned long arg) { @@ -469,11 +519,18 @@ static int __nd_ioctl(struct nvdimm_bus *nvdimm_bus, struct nvdimm *nvdimm, goto out; } + nvdimm_bus_lock(&nvdimm_bus->dev); + rc = nd_cmd_clear_to_send(nvdimm, cmd); + if (rc) + goto out_unlock; + rc = nd_desc->ndctl(nd_desc, nvdimm, cmd, buf, buf_len); if (rc < 0) - goto out; + goto out_unlock; if (copy_to_user(p, buf, buf_len)) rc = -EFAULT; + out_unlock: + nvdimm_bus_unlock(&nvdimm_bus->dev); out: vfree(buf); return rc; diff --git a/drivers/nvdimm/core.c b/drivers/nvdimm/core.c index 1b6b15d11f54..7806eaaf4707 100644 --- a/drivers/nvdimm/core.c +++ b/drivers/nvdimm/core.c @@ -54,6 +54,22 @@ bool is_nvdimm_bus_locked(struct device *dev) } EXPORT_SYMBOL(is_nvdimm_bus_locked); +u64 nd_fletcher64(void *addr, size_t len, bool le) +{ + u32 *buf = addr; + u32 lo32 = 0; + u64 hi32 = 0; + int i; + + for (i = 0; i < len / sizeof(u32); i++) { + lo32 += le ? le32_to_cpu((__le32) buf[i]) : buf[i]; + hi32 += lo32; + } + + return hi32 << 32 | lo32; +} +EXPORT_SYMBOL_GPL(nd_fletcher64); + static void nvdimm_bus_release(struct device *dev) { struct nvdimm_bus *nvdimm_bus; @@ -175,6 +191,7 @@ struct nvdimm_bus *__nvdimm_bus_register(struct device *parent, if (!nvdimm_bus) return NULL; INIT_LIST_HEAD(&nvdimm_bus->list); + init_waitqueue_head(&nvdimm_bus->probe_wait); nvdimm_bus->id = ida_simple_get(&nd_ida, 0, 0, GFP_KERNEL); mutex_init(&nvdimm_bus->reconfig_mutex); if (nvdimm_bus->id < 0) { diff --git a/drivers/nvdimm/dimm_devs.c b/drivers/nvdimm/dimm_devs.c index b3ae86f2e1da..bdf8241b6525 100644 --- a/drivers/nvdimm/dimm_devs.c +++ b/drivers/nvdimm/dimm_devs.c @@ -185,7 +185,24 @@ static ssize_t commands_show(struct device *dev, } static DEVICE_ATTR_RO(commands); +static ssize_t state_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct nvdimm *nvdimm = to_nvdimm(dev); + + /* + * The state may be in the process of changing, userspace should + * quiesce probing if it wants a static answer + */ + nvdimm_bus_lock(dev); + nvdimm_bus_unlock(dev); + return sprintf(buf, "%s\n", atomic_read(&nvdimm->busy) + ? "active" : "idle"); +} +static DEVICE_ATTR_RO(state); + static struct attribute *nvdimm_attributes[] = { + &dev_attr_state.attr, &dev_attr_commands.attr, NULL, }; @@ -213,7 +230,7 @@ struct nvdimm *nvdimm_create(struct nvdimm_bus *nvdimm_bus, void *provider_data, nvdimm->provider_data = provider_data; nvdimm->flags = flags; nvdimm->dsm_mask = dsm_mask; - + atomic_set(&nvdimm->busy, 0); dev = &nvdimm->dev; dev_set_name(dev, "nmem%d", nvdimm->id); dev->parent = &nvdimm_bus->dev; diff --git a/drivers/nvdimm/nd-core.h b/drivers/nvdimm/nd-core.h index 0e9b41fd2546..6a4b2c066ee7 100644 --- a/drivers/nvdimm/nd-core.h +++ b/drivers/nvdimm/nd-core.h @@ -14,6 +14,9 @@ #define __ND_CORE_H__ #include #include +#include +#include +#include extern struct list_head nvdimm_bus_list; extern struct mutex nvdimm_bus_list_mutex; @@ -21,10 +24,11 @@ extern int nvdimm_major; struct nvdimm_bus { struct nvdimm_bus_descriptor *nd_desc; + wait_queue_head_t probe_wait; struct module *module; struct list_head list; struct device dev; - int id; + int id, probe_active; struct mutex reconfig_mutex; }; @@ -33,6 +37,7 @@ struct nvdimm { void *provider_data; unsigned long *dsm_mask; struct device dev; + atomic_t busy; int id; }; @@ -42,10 +47,13 @@ bool is_nd_pmem(struct device *dev); struct nvdimm_bus *walk_to_nvdimm_bus(struct device *nd_dev); int __init nvdimm_bus_init(void); void nvdimm_bus_exit(void); +void nd_region_probe_success(struct nvdimm_bus *nvdimm_bus, struct device *dev); +void nd_region_disable(struct nvdimm_bus *nvdimm_bus, struct device *dev); int nvdimm_bus_create_ndctl(struct nvdimm_bus *nvdimm_bus); void nvdimm_bus_destroy_ndctl(struct nvdimm_bus *nvdimm_bus); void nd_synchronize(void); int nvdimm_bus_register_dimms(struct nvdimm_bus *nvdimm_bus); int nvdimm_bus_register_regions(struct nvdimm_bus *nvdimm_bus); +int nvdimm_bus_init_interleave_sets(struct nvdimm_bus *nvdimm_bus); int nd_match_dimm(struct device *dev, void *data); #endif /* __ND_CORE_H__ */ diff --git a/drivers/nvdimm/nd.h b/drivers/nvdimm/nd.h index bc5a08e36a25..0285e4588b03 100644 --- a/drivers/nvdimm/nd.h +++ b/drivers/nvdimm/nd.h @@ -35,6 +35,7 @@ struct nd_region { u64 ndr_start; int id; void *provider_data; + struct nd_interleave_set *nd_set; struct nd_mapping mapping[0]; }; diff --git a/drivers/nvdimm/region_devs.c b/drivers/nvdimm/region_devs.c index b5c5b9095b28..1571424578f0 100644 --- a/drivers/nvdimm/region_devs.c +++ b/drivers/nvdimm/region_devs.c @@ -10,7 +10,10 @@ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. */ +#include +#include #include +#include #include #include "nd-core.h" #include "nd.h" @@ -133,6 +136,21 @@ static ssize_t nstype_show(struct device *dev, } static DEVICE_ATTR_RO(nstype); +static ssize_t set_cookie_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct nd_region *nd_region = to_nd_region(dev); + struct nd_interleave_set *nd_set = nd_region->nd_set; + + if (is_nd_pmem(dev) && nd_set) + /* pass, should be precluded by region_visible */; + else + return -ENXIO; + + return sprintf(buf, "%#llx\n", nd_set->cookie); +} +static DEVICE_ATTR_RO(set_cookie); + static ssize_t init_namespaces_show(struct device *dev, struct device_attribute *attr, char *buf) { @@ -154,15 +172,65 @@ static struct attribute *nd_region_attributes[] = { &dev_attr_size.attr, &dev_attr_nstype.attr, &dev_attr_mappings.attr, + &dev_attr_set_cookie.attr, &dev_attr_init_namespaces.attr, NULL, }; +static umode_t region_visible(struct kobject *kobj, struct attribute *a, int n) +{ + struct device *dev = container_of(kobj, typeof(*dev), kobj); + struct nd_region *nd_region = to_nd_region(dev); + struct nd_interleave_set *nd_set = nd_region->nd_set; + + if (a != &dev_attr_set_cookie.attr) + return a->mode; + + if (is_nd_pmem(dev) && nd_set) + return a->mode; + + return 0; +} + struct attribute_group nd_region_attribute_group = { .attrs = nd_region_attributes, + .is_visible = region_visible, }; EXPORT_SYMBOL_GPL(nd_region_attribute_group); +/* + * Upon successful probe/remove, take/release a reference on the + * associated interleave set (if present) + */ +static void nd_region_notify_driver_action(struct nvdimm_bus *nvdimm_bus, + struct device *dev, bool probe) +{ + if (is_nd_pmem(dev) || is_nd_blk(dev)) { + struct nd_region *nd_region = to_nd_region(dev); + int i; + + for (i = 0; i < nd_region->ndr_mappings; i++) { + struct nd_mapping *nd_mapping = &nd_region->mapping[i]; + struct nvdimm *nvdimm = nd_mapping->nvdimm; + + if (probe) + atomic_inc(&nvdimm->busy); + else + atomic_dec(&nvdimm->busy); + } + } +} + +void nd_region_probe_success(struct nvdimm_bus *nvdimm_bus, struct device *dev) +{ + nd_region_notify_driver_action(nvdimm_bus, dev, true); +} + +void nd_region_disable(struct nvdimm_bus *nvdimm_bus, struct device *dev) +{ + nd_region_notify_driver_action(nvdimm_bus, dev, false); +} + static ssize_t mappingN(struct device *dev, char *buf, int n) { struct nd_region *nd_region = to_nd_region(dev); @@ -322,6 +390,7 @@ static struct nd_region *nd_region_create(struct nvdimm_bus *nvdimm_bus, } nd_region->ndr_mappings = ndr_desc->num_mappings; nd_region->provider_data = ndr_desc->provider_data; + nd_region->nd_set = ndr_desc->nd_set; dev = &nd_region->dev; dev_set_name(dev, "region%d", nd_region->id); dev->parent = &nvdimm_bus->dev; diff --git a/include/linux/libnvdimm.h b/include/linux/libnvdimm.h index 37f966aff386..1b627b109360 100644 --- a/include/linux/libnvdimm.h +++ b/include/linux/libnvdimm.h @@ -61,11 +61,16 @@ struct nd_cmd_desc { int out_sizes[ND_CMD_MAX_ELEM]; }; +struct nd_interleave_set { + u64 cookie; +}; + struct nd_region_desc { struct resource *res; struct nd_mapping *nd_mapping; u16 num_mappings; const struct attribute_group **attr_groups; + struct nd_interleave_set *nd_set; void *provider_data; }; @@ -101,4 +106,5 @@ struct nd_region *nvdimm_blk_region_create(struct nvdimm_bus *nvdimm_bus, struct nd_region_desc *ndr_desc); struct nd_region *nvdimm_volatile_region_create(struct nvdimm_bus *nvdimm_bus, struct nd_region_desc *ndr_desc); +u64 nd_fletcher64(void *addr, size_t len, bool le); #endif /* __LIBNVDIMM_H__ */ -- 2.20.1