diff options
Diffstat (limited to 'drivers/nvdimm/pfn_devs.c')
| -rw-r--r-- | drivers/nvdimm/pfn_devs.c | 869 |
1 files changed, 869 insertions, 0 deletions
diff --git a/drivers/nvdimm/pfn_devs.c b/drivers/nvdimm/pfn_devs.c new file mode 100644 index 0000000000..0d08e21a1c --- /dev/null +++ b/drivers/nvdimm/pfn_devs.c @@ -0,0 +1,869 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright(c) 2013-2016 Intel Corporation. All rights reserved. + */ +#include <linux/memremap.h> +#include <linux/blkdev.h> +#include <linux/device.h> +#include <linux/sizes.h> +#include <linux/slab.h> +#include <linux/fs.h> +#include <linux/mm.h> +#include "nd-core.h" +#include "pfn.h" +#include "nd.h" + +static const bool page_struct_override = IS_ENABLED(CONFIG_NVDIMM_KMSAN); + +static void nd_pfn_release(struct device *dev) +{ + struct nd_region *nd_region = to_nd_region(dev->parent); + struct nd_pfn *nd_pfn = to_nd_pfn(dev); + + dev_dbg(dev, "trace\n"); + nd_detach_ndns(&nd_pfn->dev, &nd_pfn->ndns); + ida_simple_remove(&nd_region->pfn_ida, nd_pfn->id); + kfree(nd_pfn->uuid); + kfree(nd_pfn); +} + +struct nd_pfn *to_nd_pfn(struct device *dev) +{ + struct nd_pfn *nd_pfn = container_of(dev, struct nd_pfn, dev); + + WARN_ON(!is_nd_pfn(dev)); + return nd_pfn; +} +EXPORT_SYMBOL(to_nd_pfn); + +static ssize_t mode_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev); + + switch (nd_pfn->mode) { + case PFN_MODE_RAM: + return sprintf(buf, "ram\n"); + case PFN_MODE_PMEM: + return sprintf(buf, "pmem\n"); + default: + return sprintf(buf, "none\n"); + } +} + +static ssize_t mode_store(struct device *dev, + struct device_attribute *attr, const char *buf, size_t len) +{ + struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev); + ssize_t rc = 0; + + device_lock(dev); + nvdimm_bus_lock(dev); + if (dev->driver) + rc = -EBUSY; + else { + size_t n = len - 1; + + if (strncmp(buf, "pmem\n", n) == 0 + || strncmp(buf, "pmem", n) == 0) { + nd_pfn->mode = PFN_MODE_PMEM; + } else if (strncmp(buf, "ram\n", n) == 0 + || strncmp(buf, "ram", n) == 0) + nd_pfn->mode = PFN_MODE_RAM; + else if (strncmp(buf, "none\n", n) == 0 + || strncmp(buf, "none", n) == 0) + nd_pfn->mode = PFN_MODE_NONE; + else + rc = -EINVAL; + } + dev_dbg(dev, "result: %zd wrote: %s%s", rc, buf, + buf[len - 1] == '\n' ? "" : "\n"); + nvdimm_bus_unlock(dev); + device_unlock(dev); + + return rc ? rc : len; +} +static DEVICE_ATTR_RW(mode); + +static ssize_t align_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev); + + return sprintf(buf, "%ld\n", nd_pfn->align); +} + +static unsigned long *nd_pfn_supported_alignments(unsigned long *alignments) +{ + + alignments[0] = PAGE_SIZE; + + if (has_transparent_hugepage()) { + alignments[1] = HPAGE_PMD_SIZE; + if (has_transparent_pud_hugepage()) + alignments[2] = HPAGE_PUD_SIZE; + } + + return alignments; +} + +/* + * Use pmd mapping if supported as default alignment + */ +static unsigned long nd_pfn_default_alignment(void) +{ + + if (has_transparent_hugepage()) + return HPAGE_PMD_SIZE; + return PAGE_SIZE; +} + +static ssize_t align_store(struct device *dev, + struct device_attribute *attr, const char *buf, size_t len) +{ + struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev); + unsigned long aligns[MAX_NVDIMM_ALIGN] = { [0] = 0, }; + ssize_t rc; + + device_lock(dev); + nvdimm_bus_lock(dev); + rc = nd_size_select_store(dev, buf, &nd_pfn->align, + nd_pfn_supported_alignments(aligns)); + dev_dbg(dev, "result: %zd wrote: %s%s", rc, buf, + buf[len - 1] == '\n' ? "" : "\n"); + nvdimm_bus_unlock(dev); + device_unlock(dev); + + return rc ? rc : len; +} +static DEVICE_ATTR_RW(align); + +static ssize_t uuid_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev); + + if (nd_pfn->uuid) + return sprintf(buf, "%pUb\n", nd_pfn->uuid); + return sprintf(buf, "\n"); +} + +static ssize_t uuid_store(struct device *dev, + struct device_attribute *attr, const char *buf, size_t len) +{ + struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev); + ssize_t rc; + + device_lock(dev); + rc = nd_uuid_store(dev, &nd_pfn->uuid, buf, len); + dev_dbg(dev, "result: %zd wrote: %s%s", rc, buf, + buf[len - 1] == '\n' ? "" : "\n"); + device_unlock(dev); + + return rc ? rc : len; +} +static DEVICE_ATTR_RW(uuid); + +static ssize_t namespace_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev); + ssize_t rc; + + nvdimm_bus_lock(dev); + rc = sprintf(buf, "%s\n", nd_pfn->ndns + ? dev_name(&nd_pfn->ndns->dev) : ""); + nvdimm_bus_unlock(dev); + return rc; +} + +static ssize_t namespace_store(struct device *dev, + struct device_attribute *attr, const char *buf, size_t len) +{ + struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev); + ssize_t rc; + + device_lock(dev); + nvdimm_bus_lock(dev); + rc = nd_namespace_store(dev, &nd_pfn->ndns, buf, len); + dev_dbg(dev, "result: %zd wrote: %s%s", rc, buf, + buf[len - 1] == '\n' ? "" : "\n"); + nvdimm_bus_unlock(dev); + device_unlock(dev); + + return rc; +} +static DEVICE_ATTR_RW(namespace); + +static ssize_t resource_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev); + ssize_t rc; + + device_lock(dev); + if (dev->driver) { + struct nd_pfn_sb *pfn_sb = nd_pfn->pfn_sb; + u64 offset = __le64_to_cpu(pfn_sb->dataoff); + struct nd_namespace_common *ndns = nd_pfn->ndns; + u32 start_pad = __le32_to_cpu(pfn_sb->start_pad); + struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev); + + rc = sprintf(buf, "%#llx\n", (unsigned long long) nsio->res.start + + start_pad + offset); + } else { + /* no address to convey if the pfn instance is disabled */ + rc = -ENXIO; + } + device_unlock(dev); + + return rc; +} +static DEVICE_ATTR_ADMIN_RO(resource); + +static ssize_t size_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev); + ssize_t rc; + + device_lock(dev); + if (dev->driver) { + struct nd_pfn_sb *pfn_sb = nd_pfn->pfn_sb; + u64 offset = __le64_to_cpu(pfn_sb->dataoff); + struct nd_namespace_common *ndns = nd_pfn->ndns; + u32 start_pad = __le32_to_cpu(pfn_sb->start_pad); + u32 end_trunc = __le32_to_cpu(pfn_sb->end_trunc); + struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev); + + rc = sprintf(buf, "%llu\n", (unsigned long long) + resource_size(&nsio->res) - start_pad + - end_trunc - offset); + } else { + /* no size to convey if the pfn instance is disabled */ + rc = -ENXIO; + } + device_unlock(dev); + + return rc; +} +static DEVICE_ATTR_RO(size); + +static ssize_t supported_alignments_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + unsigned long aligns[MAX_NVDIMM_ALIGN] = { [0] = 0, }; + + return nd_size_select_show(0, + nd_pfn_supported_alignments(aligns), buf); +} +static DEVICE_ATTR_RO(supported_alignments); + +static struct attribute *nd_pfn_attributes[] = { + &dev_attr_mode.attr, + &dev_attr_namespace.attr, + &dev_attr_uuid.attr, + &dev_attr_align.attr, + &dev_attr_resource.attr, + &dev_attr_size.attr, + &dev_attr_supported_alignments.attr, + NULL, +}; + +static struct attribute_group nd_pfn_attribute_group = { + .attrs = nd_pfn_attributes, +}; + +const struct attribute_group *nd_pfn_attribute_groups[] = { + &nd_pfn_attribute_group, + &nd_device_attribute_group, + &nd_numa_attribute_group, + NULL, +}; + +static const struct device_type nd_pfn_device_type = { + .name = "nd_pfn", + .release = nd_pfn_release, + .groups = nd_pfn_attribute_groups, +}; + +bool is_nd_pfn(struct device *dev) +{ + return dev ? dev->type == &nd_pfn_device_type : false; +} +EXPORT_SYMBOL(is_nd_pfn); + +static struct lock_class_key nvdimm_pfn_key; + +struct device *nd_pfn_devinit(struct nd_pfn *nd_pfn, + struct nd_namespace_common *ndns) +{ + struct device *dev; + + if (!nd_pfn) + return NULL; + + nd_pfn->mode = PFN_MODE_NONE; + nd_pfn->align = nd_pfn_default_alignment(); + dev = &nd_pfn->dev; + device_initialize(&nd_pfn->dev); + lockdep_set_class(&nd_pfn->dev.mutex, &nvdimm_pfn_key); + if (ndns && !__nd_attach_ndns(&nd_pfn->dev, ndns, &nd_pfn->ndns)) { + dev_dbg(&ndns->dev, "failed, already claimed by %s\n", + dev_name(ndns->claim)); + put_device(dev); + return NULL; + } + return dev; +} + +static struct nd_pfn *nd_pfn_alloc(struct nd_region *nd_region) +{ + struct nd_pfn *nd_pfn; + struct device *dev; + + nd_pfn = kzalloc(sizeof(*nd_pfn), GFP_KERNEL); + if (!nd_pfn) + return NULL; + + nd_pfn->id = ida_simple_get(&nd_region->pfn_ida, 0, 0, GFP_KERNEL); + if (nd_pfn->id < 0) { + kfree(nd_pfn); + return NULL; + } + + dev = &nd_pfn->dev; + dev_set_name(dev, "pfn%d.%d", nd_region->id, nd_pfn->id); + dev->type = &nd_pfn_device_type; + dev->parent = &nd_region->dev; + + return nd_pfn; +} + +struct device *nd_pfn_create(struct nd_region *nd_region) +{ + struct nd_pfn *nd_pfn; + struct device *dev; + + if (!is_memory(&nd_region->dev)) + return NULL; + + nd_pfn = nd_pfn_alloc(nd_region); + dev = nd_pfn_devinit(nd_pfn, NULL); + + nd_device_register(dev); + return dev; +} + +/* + * nd_pfn_clear_memmap_errors() clears any errors in the volatile memmap + * space associated with the namespace. If the memmap is set to DRAM, then + * this is a no-op. Since the memmap area is freshly initialized during + * probe, we have an opportunity to clear any badblocks in this area. + */ +static int nd_pfn_clear_memmap_errors(struct nd_pfn *nd_pfn) +{ + struct nd_region *nd_region = to_nd_region(nd_pfn->dev.parent); + struct nd_namespace_common *ndns = nd_pfn->ndns; + void *zero_page = page_address(ZERO_PAGE(0)); + struct nd_pfn_sb *pfn_sb = nd_pfn->pfn_sb; + int num_bad, meta_num, rc, bb_present; + sector_t first_bad, meta_start; + struct nd_namespace_io *nsio; + + if (nd_pfn->mode != PFN_MODE_PMEM) + return 0; + + nsio = to_nd_namespace_io(&ndns->dev); + meta_start = (SZ_4K + sizeof(*pfn_sb)) >> 9; + meta_num = (le64_to_cpu(pfn_sb->dataoff) >> 9) - meta_start; + + /* + * re-enable the namespace with correct size so that we can access + * the device memmap area. + */ + devm_namespace_disable(&nd_pfn->dev, ndns); + rc = devm_namespace_enable(&nd_pfn->dev, ndns, le64_to_cpu(pfn_sb->dataoff)); + if (rc) + return rc; + + do { + unsigned long zero_len; + u64 nsoff; + + bb_present = badblocks_check(&nd_region->bb, meta_start, + meta_num, &first_bad, &num_bad); + if (bb_present) { + dev_dbg(&nd_pfn->dev, "meta: %x badblocks at %llx\n", + num_bad, first_bad); + nsoff = ALIGN_DOWN((nd_region->ndr_start + + (first_bad << 9)) - nsio->res.start, + PAGE_SIZE); + zero_len = ALIGN(num_bad << 9, PAGE_SIZE); + while (zero_len) { + unsigned long chunk = min(zero_len, PAGE_SIZE); + + rc = nvdimm_write_bytes(ndns, nsoff, zero_page, + chunk, 0); + if (rc) + break; + + zero_len -= chunk; + nsoff += chunk; + } + if (rc) { + dev_err(&nd_pfn->dev, + "error clearing %x badblocks at %llx\n", + num_bad, first_bad); + return rc; + } + } + } while (bb_present); + + return 0; +} + +static bool nd_supported_alignment(unsigned long align) +{ + int i; + unsigned long supported[MAX_NVDIMM_ALIGN] = { [0] = 0, }; + + if (align == 0) + return false; + + nd_pfn_supported_alignments(supported); + for (i = 0; supported[i]; i++) + if (align == supported[i]) + return true; + return false; +} + +/** + * nd_pfn_validate - read and validate info-block + * @nd_pfn: fsdax namespace runtime state / properties + * @sig: 'devdax' or 'fsdax' signature + * + * Upon return the info-block buffer contents (->pfn_sb) are + * indeterminate when validation fails, and a coherent info-block + * otherwise. + */ +int nd_pfn_validate(struct nd_pfn *nd_pfn, const char *sig) +{ + u64 checksum, offset; + struct resource *res; + enum nd_pfn_mode mode; + resource_size_t res_size; + struct nd_namespace_io *nsio; + unsigned long align, start_pad, end_trunc; + struct nd_pfn_sb *pfn_sb = nd_pfn->pfn_sb; + struct nd_namespace_common *ndns = nd_pfn->ndns; + const uuid_t *parent_uuid = nd_dev_to_uuid(&ndns->dev); + + if (!pfn_sb || !ndns) + return -ENODEV; + + if (!is_memory(nd_pfn->dev.parent)) + return -ENODEV; + + if (nvdimm_read_bytes(ndns, SZ_4K, pfn_sb, sizeof(*pfn_sb), 0)) + return -ENXIO; + + if (memcmp(pfn_sb->signature, sig, PFN_SIG_LEN) != 0) + return -ENODEV; + + checksum = le64_to_cpu(pfn_sb->checksum); + pfn_sb->checksum = 0; + if (checksum != nd_sb_checksum((struct nd_gen_sb *) pfn_sb)) + return -ENODEV; + pfn_sb->checksum = cpu_to_le64(checksum); + + if (memcmp(pfn_sb->parent_uuid, parent_uuid, 16) != 0) + return -ENODEV; + + if (__le16_to_cpu(pfn_sb->version_minor) < 1) { + pfn_sb->start_pad = 0; + pfn_sb->end_trunc = 0; + } + + if (__le16_to_cpu(pfn_sb->version_minor) < 2) + pfn_sb->align = 0; + + if (__le16_to_cpu(pfn_sb->version_minor) < 4) { + pfn_sb->page_struct_size = cpu_to_le16(64); + pfn_sb->page_size = cpu_to_le32(PAGE_SIZE); + } + + switch (le32_to_cpu(pfn_sb->mode)) { + case PFN_MODE_RAM: + case PFN_MODE_PMEM: + break; + default: + return -ENXIO; + } + + align = le32_to_cpu(pfn_sb->align); + offset = le64_to_cpu(pfn_sb->dataoff); + start_pad = le32_to_cpu(pfn_sb->start_pad); + end_trunc = le32_to_cpu(pfn_sb->end_trunc); + if (align == 0) + align = 1UL << ilog2(offset); + mode = le32_to_cpu(pfn_sb->mode); + + if ((le32_to_cpu(pfn_sb->page_size) > PAGE_SIZE) && + (mode == PFN_MODE_PMEM)) { + dev_err(&nd_pfn->dev, + "init failed, page size mismatch %d\n", + le32_to_cpu(pfn_sb->page_size)); + return -EOPNOTSUPP; + } + + if ((le16_to_cpu(pfn_sb->page_struct_size) < sizeof(struct page)) && + (mode == PFN_MODE_PMEM)) { + dev_err(&nd_pfn->dev, + "init failed, struct page size mismatch %d\n", + le16_to_cpu(pfn_sb->page_struct_size)); + return -EOPNOTSUPP; + } + + /* + * Check whether the we support the alignment. For Dax if the + * superblock alignment is not matching, we won't initialize + * the device. + */ + if (!nd_supported_alignment(align) && + !memcmp(pfn_sb->signature, DAX_SIG, PFN_SIG_LEN)) { + dev_err(&nd_pfn->dev, "init failed, alignment mismatch: " + "%ld:%ld\n", nd_pfn->align, align); + return -EOPNOTSUPP; + } + + if (!nd_pfn->uuid) { + /* + * When probing a namepace via nd_pfn_probe() the uuid + * is NULL (see: nd_pfn_devinit()) we init settings from + * pfn_sb + */ + nd_pfn->uuid = kmemdup(pfn_sb->uuid, 16, GFP_KERNEL); + if (!nd_pfn->uuid) + return -ENOMEM; + nd_pfn->align = align; + nd_pfn->mode = mode; + } else { + /* + * When probing a pfn / dax instance we validate the + * live settings against the pfn_sb + */ + if (memcmp(nd_pfn->uuid, pfn_sb->uuid, 16) != 0) + return -ENODEV; + + /* + * If the uuid validates, but other settings mismatch + * return EINVAL because userspace has managed to change + * the configuration without specifying new + * identification. + */ + if (nd_pfn->align != align || nd_pfn->mode != mode) { + dev_err(&nd_pfn->dev, + "init failed, settings mismatch\n"); + dev_dbg(&nd_pfn->dev, "align: %lx:%lx mode: %d:%d\n", + nd_pfn->align, align, nd_pfn->mode, + mode); + return -EOPNOTSUPP; + } + } + + if (align > nvdimm_namespace_capacity(ndns)) { + dev_err(&nd_pfn->dev, "alignment: %lx exceeds capacity %llx\n", + align, nvdimm_namespace_capacity(ndns)); + return -EOPNOTSUPP; + } + + /* + * These warnings are verbose because they can only trigger in + * the case where the physical address alignment of the + * namespace has changed since the pfn superblock was + * established. + */ + nsio = to_nd_namespace_io(&ndns->dev); + res = &nsio->res; + res_size = resource_size(res); + if (offset >= res_size) { + dev_err(&nd_pfn->dev, "pfn array size exceeds capacity of %s\n", + dev_name(&ndns->dev)); + return -EOPNOTSUPP; + } + + if ((align && !IS_ALIGNED(res->start + offset + start_pad, align)) + || !IS_ALIGNED(offset, PAGE_SIZE)) { + dev_err(&nd_pfn->dev, + "bad offset: %#llx dax disabled align: %#lx\n", + offset, align); + return -EOPNOTSUPP; + } + + if (!IS_ALIGNED(res->start + start_pad, memremap_compat_align())) { + dev_err(&nd_pfn->dev, "resource start misaligned\n"); + return -EOPNOTSUPP; + } + + if (!IS_ALIGNED(res->end + 1 - end_trunc, memremap_compat_align())) { + dev_err(&nd_pfn->dev, "resource end misaligned\n"); + return -EOPNOTSUPP; + } + + if (offset >= (res_size - start_pad - end_trunc)) { + dev_err(&nd_pfn->dev, "bad offset with small namespace\n"); + return -EOPNOTSUPP; + } + return 0; +} +EXPORT_SYMBOL(nd_pfn_validate); + +int nd_pfn_probe(struct device *dev, struct nd_namespace_common *ndns) +{ + int rc; + struct nd_pfn *nd_pfn; + struct device *pfn_dev; + struct nd_pfn_sb *pfn_sb; + struct nd_region *nd_region = to_nd_region(ndns->dev.parent); + + if (ndns->force_raw) + return -ENODEV; + + switch (ndns->claim_class) { + case NVDIMM_CCLASS_NONE: + case NVDIMM_CCLASS_PFN: + break; + default: + return -ENODEV; + } + + nvdimm_bus_lock(&ndns->dev); + nd_pfn = nd_pfn_alloc(nd_region); + pfn_dev = nd_pfn_devinit(nd_pfn, ndns); + nvdimm_bus_unlock(&ndns->dev); + if (!pfn_dev) + return -ENOMEM; + pfn_sb = devm_kmalloc(dev, sizeof(*pfn_sb), GFP_KERNEL); + nd_pfn = to_nd_pfn(pfn_dev); + nd_pfn->pfn_sb = pfn_sb; + rc = nd_pfn_validate(nd_pfn, PFN_SIG); + dev_dbg(dev, "pfn: %s\n", rc == 0 ? dev_name(pfn_dev) : "<none>"); + if (rc < 0) { + nd_detach_ndns(pfn_dev, &nd_pfn->ndns); + put_device(pfn_dev); + } else + nd_device_register(pfn_dev); + + return rc; +} +EXPORT_SYMBOL(nd_pfn_probe); + +/* + * We hotplug memory at sub-section granularity, pad the reserved area + * from the previous section base to the namespace base address. + */ +static unsigned long init_altmap_base(resource_size_t base) +{ + unsigned long base_pfn = PHYS_PFN(base); + + return SUBSECTION_ALIGN_DOWN(base_pfn); +} + +static unsigned long init_altmap_reserve(resource_size_t base) +{ + unsigned long reserve = nd_info_block_reserve() >> PAGE_SHIFT; + unsigned long base_pfn = PHYS_PFN(base); + + reserve += base_pfn - SUBSECTION_ALIGN_DOWN(base_pfn); + return reserve; +} + +static int __nvdimm_setup_pfn(struct nd_pfn *nd_pfn, struct dev_pagemap *pgmap) +{ + struct range *range = &pgmap->range; + struct vmem_altmap *altmap = &pgmap->altmap; + struct nd_pfn_sb *pfn_sb = nd_pfn->pfn_sb; + u64 offset = le64_to_cpu(pfn_sb->dataoff); + u32 start_pad = __le32_to_cpu(pfn_sb->start_pad); + u32 end_trunc = __le32_to_cpu(pfn_sb->end_trunc); + u32 reserve = nd_info_block_reserve(); + struct nd_namespace_common *ndns = nd_pfn->ndns; + struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev); + resource_size_t base = nsio->res.start + start_pad; + resource_size_t end = nsio->res.end - end_trunc; + struct vmem_altmap __altmap = { + .base_pfn = init_altmap_base(base), + .reserve = init_altmap_reserve(base), + .end_pfn = PHYS_PFN(end), + }; + + *range = (struct range) { + .start = nsio->res.start + start_pad, + .end = nsio->res.end - end_trunc, + }; + pgmap->nr_range = 1; + if (nd_pfn->mode == PFN_MODE_RAM) { + if (offset < reserve) + return -EINVAL; + nd_pfn->npfns = le64_to_cpu(pfn_sb->npfns); + } else if (nd_pfn->mode == PFN_MODE_PMEM) { + nd_pfn->npfns = PHYS_PFN((range_len(range) - offset)); + if (le64_to_cpu(nd_pfn->pfn_sb->npfns) > nd_pfn->npfns) + dev_info(&nd_pfn->dev, + "number of pfns truncated from %lld to %ld\n", + le64_to_cpu(nd_pfn->pfn_sb->npfns), + nd_pfn->npfns); + memcpy(altmap, &__altmap, sizeof(*altmap)); + altmap->free = PHYS_PFN(offset - reserve); + altmap->alloc = 0; + pgmap->flags |= PGMAP_ALTMAP_VALID; + } else + return -ENXIO; + + return 0; +} + +static int nd_pfn_init(struct nd_pfn *nd_pfn) +{ + struct nd_namespace_common *ndns = nd_pfn->ndns; + struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev); + resource_size_t start, size; + struct nd_region *nd_region; + unsigned long npfns, align; + u32 end_trunc; + struct nd_pfn_sb *pfn_sb; + phys_addr_t offset; + const char *sig; + u64 checksum; + int rc; + + pfn_sb = devm_kmalloc(&nd_pfn->dev, sizeof(*pfn_sb), GFP_KERNEL); + if (!pfn_sb) + return -ENOMEM; + + nd_pfn->pfn_sb = pfn_sb; + if (is_nd_dax(&nd_pfn->dev)) + sig = DAX_SIG; + else + sig = PFN_SIG; + + rc = nd_pfn_validate(nd_pfn, sig); + if (rc == 0) + return nd_pfn_clear_memmap_errors(nd_pfn); + if (rc != -ENODEV) + return rc; + + /* no info block, do init */; + memset(pfn_sb, 0, sizeof(*pfn_sb)); + + nd_region = to_nd_region(nd_pfn->dev.parent); + if (nd_region->ro) { + dev_info(&nd_pfn->dev, + "%s is read-only, unable to init metadata\n", + dev_name(&nd_region->dev)); + return -ENXIO; + } + + start = nsio->res.start; + size = resource_size(&nsio->res); + npfns = PHYS_PFN(size - SZ_8K); + align = max(nd_pfn->align, memremap_compat_align()); + + /* + * When @start is misaligned fail namespace creation. See + * the 'struct nd_pfn_sb' commentary on why ->start_pad is not + * an option. + */ + if (!IS_ALIGNED(start, memremap_compat_align())) { + dev_err(&nd_pfn->dev, "%s: start %pa misaligned to %#lx\n", + dev_name(&ndns->dev), &start, + memremap_compat_align()); + return -EINVAL; + } + end_trunc = start + size - ALIGN_DOWN(start + size, align); + if (nd_pfn->mode == PFN_MODE_PMEM) { + unsigned long page_map_size = MAX_STRUCT_PAGE_SIZE * npfns; + + /* + * The altmap should be padded out to the block size used + * when populating the vmemmap. This *should* be equal to + * PMD_SIZE for most architectures. + * + * Also make sure size of struct page is less than + * MAX_STRUCT_PAGE_SIZE. The goal here is compatibility in the + * face of production kernel configurations that reduce the + * 'struct page' size below MAX_STRUCT_PAGE_SIZE. For debug + * kernel configurations that increase the 'struct page' size + * above MAX_STRUCT_PAGE_SIZE, the page_struct_override allows + * for continuing with the capacity that will be wasted when + * reverting to a production kernel configuration. Otherwise, + * those configurations are blocked by default. + */ + if (sizeof(struct page) > MAX_STRUCT_PAGE_SIZE) { + if (page_struct_override) + page_map_size = sizeof(struct page) * npfns; + else { + dev_err(&nd_pfn->dev, + "Memory debug options prevent using pmem for the page map\n"); + return -EINVAL; + } + } + offset = ALIGN(start + SZ_8K + page_map_size, align) - start; + } else if (nd_pfn->mode == PFN_MODE_RAM) + offset = ALIGN(start + SZ_8K, align) - start; + else + return -ENXIO; + + if (offset >= (size - end_trunc)) { + /* This results in zero size devices */ + dev_err(&nd_pfn->dev, "%s unable to satisfy requested alignment\n", + dev_name(&ndns->dev)); + return -ENXIO; + } + + npfns = PHYS_PFN(size - offset - end_trunc); + pfn_sb->mode = cpu_to_le32(nd_pfn->mode); + pfn_sb->dataoff = cpu_to_le64(offset); + pfn_sb->npfns = cpu_to_le64(npfns); + memcpy(pfn_sb->signature, sig, PFN_SIG_LEN); + memcpy(pfn_sb->uuid, nd_pfn->uuid, 16); + memcpy(pfn_sb->parent_uuid, nd_dev_to_uuid(&ndns->dev), 16); + pfn_sb->version_major = cpu_to_le16(1); + pfn_sb->version_minor = cpu_to_le16(4); + pfn_sb->end_trunc = cpu_to_le32(end_trunc); + pfn_sb->align = cpu_to_le32(nd_pfn->align); + if (sizeof(struct page) > MAX_STRUCT_PAGE_SIZE && page_struct_override) + pfn_sb->page_struct_size = cpu_to_le16(sizeof(struct page)); + else + pfn_sb->page_struct_size = cpu_to_le16(MAX_STRUCT_PAGE_SIZE); + pfn_sb->page_size = cpu_to_le32(PAGE_SIZE); + checksum = nd_sb_checksum((struct nd_gen_sb *) pfn_sb); + pfn_sb->checksum = cpu_to_le64(checksum); + + rc = nd_pfn_clear_memmap_errors(nd_pfn); + if (rc) + return rc; + + return nvdimm_write_bytes(ndns, SZ_4K, pfn_sb, sizeof(*pfn_sb), 0); +} + +/* + * Determine the effective resource range and vmem_altmap from an nd_pfn + * instance. + */ +int nvdimm_setup_pfn(struct nd_pfn *nd_pfn, struct dev_pagemap *pgmap) +{ + int rc; + + if (!nd_pfn->uuid || !nd_pfn->ndns) + return -ENODEV; + + rc = nd_pfn_init(nd_pfn); + if (rc) + return rc; + + /* we need a valid pfn_sb before we can init a dev_pagemap */ + return __nvdimm_setup_pfn(nd_pfn, pgmap); +} +EXPORT_SYMBOL_GPL(nvdimm_setup_pfn); |