// SPDX-License-Identifier: GPL-2.0-only /* * Copyright(c) 2013-2015 Intel Corporation. All rights reserved. */ #include <linux/device.h> #include <linux/sizes.h> #include "nd-core.h" #include "pmem.h" #include "pfn.h" #include "btt.h" #include "nd.h" void __nd_detach_ndns(struct device *dev, struct nd_namespace_common **_ndns) { struct nd_namespace_common *ndns = *_ndns; struct nvdimm_bus *nvdimm_bus; if (!ndns) return; nvdimm_bus = walk_to_nvdimm_bus(&ndns->dev); lockdep_assert_held(&nvdimm_bus->reconfig_mutex); dev_WARN_ONCE(dev, ndns->claim != dev, "%s: invalid claim\n", __func__); ndns->claim = NULL; *_ndns = NULL; put_device(&ndns->dev); } void nd_detach_ndns(struct device *dev, struct nd_namespace_common **_ndns) { struct nd_namespace_common *ndns = *_ndns; if (!ndns) return; get_device(&ndns->dev); nvdimm_bus_lock(&ndns->dev); __nd_detach_ndns(dev, _ndns); nvdimm_bus_unlock(&ndns->dev); put_device(&ndns->dev); } bool __nd_attach_ndns(struct device *dev, struct nd_namespace_common *attach, struct nd_namespace_common **_ndns) { struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(&attach->dev); if (attach->claim) return false; lockdep_assert_held(&nvdimm_bus->reconfig_mutex); dev_WARN_ONCE(dev, *_ndns, "%s: invalid claim\n", __func__); attach->claim = dev; *_ndns = attach; get_device(&attach->dev); return true; } bool nd_attach_ndns(struct device *dev, struct nd_namespace_common *attach, struct nd_namespace_common **_ndns) { bool claimed; nvdimm_bus_lock(&attach->dev); claimed = __nd_attach_ndns(dev, attach, _ndns); nvdimm_bus_unlock(&attach->dev); return claimed; } static int namespace_match(struct device *dev, void *data) { char *name = data; return strcmp(name, dev_name(dev)) == 0; } static bool is_idle(struct device *dev, struct nd_namespace_common *ndns) { struct nd_region *nd_region = to_nd_region(dev->parent); struct device *seed = NULL; if (is_nd_btt(dev)) seed = nd_region->btt_seed; else if (is_nd_pfn(dev)) seed = nd_region->pfn_seed; else if (is_nd_dax(dev)) seed = nd_region->dax_seed; if (seed == dev || ndns || dev->driver) return false; return true; } struct nd_pfn *to_nd_pfn_safe(struct device *dev) { /* * pfn device attributes are re-used by dax device instances, so we * need to be careful to correct device-to-nd_pfn conversion. */ if (is_nd_pfn(dev)) return to_nd_pfn(dev); if (is_nd_dax(dev)) { struct nd_dax *nd_dax = to_nd_dax(dev); return &nd_dax->nd_pfn; } WARN_ON(1); return NULL; } static void nd_detach_and_reset(struct device *dev, struct nd_namespace_common **_ndns) { /* detach the namespace and destroy / reset the device */ __nd_detach_ndns(dev, _ndns); if (is_idle(dev, *_ndns)) { nd_device_unregister(dev, ND_ASYNC); } else if (is_nd_btt(dev)) { struct nd_btt *nd_btt = to_nd_btt(dev); nd_btt->lbasize = 0; kfree(nd_btt->uuid); nd_btt->uuid = NULL; } else if (is_nd_pfn(dev) || is_nd_dax(dev)) { struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev); kfree(nd_pfn->uuid); nd_pfn->uuid = NULL; nd_pfn->mode = PFN_MODE_NONE; } } ssize_t nd_namespace_store(struct device *dev, struct nd_namespace_common **_ndns, const char *buf, size_t len) { struct nd_namespace_common *ndns; struct device *found; char *name; if (dev->driver) { dev_dbg(dev, "namespace already active\n"); return -EBUSY; } name = kstrndup(buf, len, GFP_KERNEL); if (!name) return -ENOMEM; strim(name); if (strncmp(name, "namespace", 9) == 0 || strcmp(name, "") == 0) /* pass */; else { len = -EINVAL; goto out; } ndns = *_ndns; if (strcmp(name, "") == 0) { nd_detach_and_reset(dev, _ndns); goto out; } else if (ndns) { dev_dbg(dev, "namespace already set to: %s\n", dev_name(&ndns->dev)); len = -EBUSY; goto out; } found = device_find_child(dev->parent, name, namespace_match); if (!found) { dev_dbg(dev, "'%s' not found under %s\n", name, dev_name(dev->parent)); len = -ENODEV; goto out; } ndns = to_ndns(found); switch (ndns->claim_class) { case NVDIMM_CCLASS_NONE: break; case NVDIMM_CCLASS_BTT: case NVDIMM_CCLASS_BTT2: if (!is_nd_btt(dev)) { len = -EBUSY; goto out_attach; } break; case NVDIMM_CCLASS_PFN: if (!is_nd_pfn(dev)) { len = -EBUSY; goto out_attach; } break; case NVDIMM_CCLASS_DAX: if (!is_nd_dax(dev)) { len = -EBUSY; goto out_attach; } break; default: len = -EBUSY; goto out_attach; break; } if (__nvdimm_namespace_capacity(ndns) < SZ_16M) { dev_dbg(dev, "%s too small to host\n", name); len = -ENXIO; goto out_attach; } WARN_ON_ONCE(!is_nvdimm_bus_locked(dev)); if (!__nd_attach_ndns(dev, ndns, _ndns)) { dev_dbg(dev, "%s already claimed\n", dev_name(&ndns->dev)); len = -EBUSY; } out_attach: put_device(&ndns->dev); /* from device_find_child */ out: kfree(name); return len; } /* * nd_sb_checksum: compute checksum for a generic info block * * Returns a fletcher64 checksum of everything in the given info block * except the last field (since that's where the checksum lives). */ u64 nd_sb_checksum(struct nd_gen_sb *nd_gen_sb) { u64 sum; __le64 sum_save; BUILD_BUG_ON(sizeof(struct btt_sb) != SZ_4K); BUILD_BUG_ON(sizeof(struct nd_pfn_sb) != SZ_4K); BUILD_BUG_ON(sizeof(struct nd_gen_sb) != SZ_4K); sum_save = nd_gen_sb->checksum; nd_gen_sb->checksum = 0; sum = nd_fletcher64(nd_gen_sb, sizeof(*nd_gen_sb), 1); nd_gen_sb->checksum = sum_save; return sum; } EXPORT_SYMBOL(nd_sb_checksum); static int nsio_rw_bytes(struct nd_namespace_common *ndns, resource_size_t offset, void *buf, size_t size, int rw, unsigned long flags) { struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev); unsigned int sz_align = ALIGN(size + (offset & (512 - 1)), 512); sector_t sector = offset >> 9; int rc = 0, ret = 0; if (unlikely(!size)) return 0; if (unlikely(offset + size > nsio->size)) { dev_WARN_ONCE(&ndns->dev, 1, "request out of range\n"); return -EFAULT; } if (rw == READ) { if (unlikely(is_bad_pmem(&nsio->bb, sector, sz_align))) return -EIO; if (memcpy_mcsafe(buf, nsio->addr + offset, size) != 0) return -EIO; return 0; } if (unlikely(is_bad_pmem(&nsio->bb, sector, sz_align))) { if (IS_ALIGNED(offset, 512) && IS_ALIGNED(size, 512) && !(flags & NVDIMM_IO_ATOMIC)) { long cleared; might_sleep(); cleared = nvdimm_clear_poison(&ndns->dev, nsio->res.start + offset, size); if (cleared < size) rc = -EIO; if (cleared > 0 && cleared / 512) { cleared /= 512; badblocks_clear(&nsio->bb, sector, cleared); } arch_invalidate_pmem(nsio->addr + offset, size); } else rc = -EIO; } memcpy_flushcache(nsio->addr + offset, buf, size); ret = nvdimm_flush(to_nd_region(ndns->dev.parent), NULL); if (ret) rc = ret; return rc; } int devm_nsio_enable(struct device *dev, struct nd_namespace_io *nsio, resource_size_t size) { struct resource *res = &nsio->res; struct nd_namespace_common *ndns = &nsio->common; nsio->size = size; if (!devm_request_mem_region(dev, res->start, size, dev_name(&ndns->dev))) { dev_warn(dev, "could not reserve region %pR\n", res); return -EBUSY; } ndns->rw_bytes = nsio_rw_bytes; if (devm_init_badblocks(dev, &nsio->bb)) return -ENOMEM; nvdimm_badblocks_populate(to_nd_region(ndns->dev.parent), &nsio->bb, &nsio->res); nsio->addr = devm_memremap(dev, res->start, size, ARCH_MEMREMAP_PMEM); return PTR_ERR_OR_ZERO(nsio->addr); } void devm_nsio_disable(struct device *dev, struct nd_namespace_io *nsio) { struct resource *res = &nsio->res; devm_memunmap(dev, nsio->addr); devm_exit_badblocks(dev, &nsio->bb); devm_release_mem_region(dev, res->start, nsio->size); }