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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
commit | 76cb841cb886eef6b3bee341a2266c76578724ad (patch) | |
tree | f5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /drivers/nvdimm/claim.c | |
parent | Initial commit. (diff) | |
download | linux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip |
Adding upstream version 4.19.249.upstream/4.19.249upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/nvdimm/claim.c')
-rw-r--r-- | drivers/nvdimm/claim.c | 342 |
1 files changed, 342 insertions, 0 deletions
diff --git a/drivers/nvdimm/claim.c b/drivers/nvdimm/claim.c new file mode 100644 index 000000000..fb667bf46 --- /dev/null +++ b/drivers/nvdimm/claim.c @@ -0,0 +1,342 @@ +/* + * Copyright(c) 2013-2015 Intel Corporation. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of version 2 of the GNU General Public License as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + */ +#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; + + 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); + nvdimm_flush(to_nd_region(ndns->dev.parent)); + + return rc; +} + +int devm_nsio_enable(struct device *dev, struct nd_namespace_io *nsio) +{ + struct resource *res = &nsio->res; + struct nd_namespace_common *ndns = &nsio->common; + + nsio->size = resource_size(res); + if (!devm_request_mem_region(dev, res->start, resource_size(res), + 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, resource_size(res), + ARCH_MEMREMAP_PMEM); + + return PTR_ERR_OR_ZERO(nsio->addr); +} +EXPORT_SYMBOL_GPL(devm_nsio_enable); + +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, resource_size(res)); +} +EXPORT_SYMBOL_GPL(devm_nsio_disable); |