diff options
author | Dan Williams <dan.j.williams@intel.com> | 2015-07-31 00:57:47 +0300 |
---|---|---|
committer | Dan Williams <dan.j.williams@intel.com> | 2015-08-29 06:39:36 +0300 |
commit | e1455744b27c9e6115c3508a7b2902157c2c4347 (patch) | |
tree | 6bfbc5d78269c9389f5bcfc1adc35d4f7f2e6fa4 /drivers/nvdimm/pfn_devs.c | |
parent | 96601adb745186ccbcf5b078d4756f13381ec2af (diff) |
libnvdimm, pfn: 'struct page' provider infrastructure
Implement the base infrastructure for libnvdimm PFN devices. Similar to
BTT devices they take a namespace as a backing device and layer
functionality on top. In this case the functionality is reserving space
for an array of 'struct page' entries to be handed out through
pfn_to_page(). For now this is just the basic libnvdimm-device-model for
configuring the base PFN device.
As the namespace claiming mechanism for PFN devices is mostly identical
to BTT devices drivers/nvdimm/claim.c is created to house the common
bits.
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Diffstat (limited to 'drivers/nvdimm/pfn_devs.c')
-rw-r--r-- | drivers/nvdimm/pfn_devs.c | 336 |
1 files changed, 336 insertions, 0 deletions
diff --git a/drivers/nvdimm/pfn_devs.c b/drivers/nvdimm/pfn_devs.c new file mode 100644 index 000000000000..f708d63709a5 --- /dev/null +++ b/drivers/nvdimm/pfn_devs.c @@ -0,0 +1,336 @@ +/* + * 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/blkdev.h> +#include <linux/device.h> +#include <linux/genhd.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 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, "%s\n", __func__); + 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); +} + +static struct device_type nd_pfn_device_type = { + .name = "nd_pfn", + .release = nd_pfn_release, +}; + +bool is_nd_pfn(struct device *dev) +{ + return dev ? dev->type == &nd_pfn_device_type : false; +} +EXPORT_SYMBOL(is_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(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(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) { + /* TODO: allocate from PMEM support */ + rc = -ENOTTY; + } 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, "%s: result: %zd wrote: %s%s", __func__, + 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 uuid_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct nd_pfn *nd_pfn = to_nd_pfn(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(dev); + ssize_t rc; + + device_lock(dev); + rc = nd_uuid_store(dev, &nd_pfn->uuid, buf, len); + dev_dbg(dev, "%s: result: %zd wrote: %s%s", __func__, + 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(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(dev); + ssize_t rc; + + nvdimm_bus_lock(dev); + device_lock(dev); + rc = nd_namespace_store(dev, &nd_pfn->ndns, buf, len); + dev_dbg(dev, "%s: result: %zd wrote: %s%s", __func__, + rc, buf, buf[len - 1] == '\n' ? "" : "\n"); + device_unlock(dev); + nvdimm_bus_unlock(dev); + + return rc; +} +static DEVICE_ATTR_RW(namespace); + +static struct attribute *nd_pfn_attributes[] = { + &dev_attr_mode.attr, + &dev_attr_namespace.attr, + &dev_attr_uuid.attr, + NULL, +}; + +static struct attribute_group nd_pfn_attribute_group = { + .attrs = nd_pfn_attributes, +}; + +static const struct attribute_group *nd_pfn_attribute_groups[] = { + &nd_pfn_attribute_group, + &nd_device_attribute_group, + &nd_numa_attribute_group, + NULL, +}; + +static struct device *__nd_pfn_create(struct nd_region *nd_region, + u8 *uuid, enum nd_pfn_mode mode, + struct nd_namespace_common *ndns) +{ + struct nd_pfn *nd_pfn; + struct device *dev; + + /* we can only create pages for contiguous ranged of pmem */ + if (!is_nd_pmem(&nd_region->dev)) + return NULL; + + 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; + } + + nd_pfn->mode = mode; + if (uuid) + uuid = kmemdup(uuid, 16, GFP_KERNEL); + nd_pfn->uuid = uuid; + dev = &nd_pfn->dev; + dev_set_name(dev, "pfn%d.%d", nd_region->id, nd_pfn->id); + dev->parent = &nd_region->dev; + dev->type = &nd_pfn_device_type; + dev->groups = nd_pfn_attribute_groups; + device_initialize(&nd_pfn->dev); + if (ndns && !__nd_attach_ndns(&nd_pfn->dev, ndns, &nd_pfn->ndns)) { + dev_dbg(&ndns->dev, "%s failed, already claimed by %s\n", + __func__, dev_name(ndns->claim)); + put_device(dev); + return NULL; + } + return dev; +} + +struct device *nd_pfn_create(struct nd_region *nd_region) +{ + struct device *dev = __nd_pfn_create(nd_region, NULL, PFN_MODE_NONE, + NULL); + + if (dev) + __nd_device_register(dev); + return dev; +} + +static int nd_pfn_validate(struct nd_pfn *nd_pfn) +{ + struct nd_namespace_common *ndns = nd_pfn->ndns; + struct nd_pfn_sb *pfn_sb = nd_pfn->pfn_sb; + struct nd_namespace_io *nsio; + u64 checksum, offset; + + if (!pfn_sb || !ndns) + return -ENODEV; + + if (!is_nd_pmem(nd_pfn->dev.parent)) + return -ENODEV; + + /* section alignment for simple hotplug */ + if (nvdimm_namespace_capacity(ndns) < ND_PFN_ALIGN) + return -ENODEV; + + if (nvdimm_read_bytes(ndns, SZ_4K, pfn_sb, sizeof(*pfn_sb))) + return -ENXIO; + + if (memcmp(pfn_sb->signature, PFN_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); + + switch (le32_to_cpu(pfn_sb->mode)) { + case PFN_MODE_RAM: + break; + case PFN_MODE_PMEM: + /* TODO: allocate from PMEM support */ + return -ENOTTY; + default: + return -ENXIO; + } + + if (!nd_pfn->uuid) { + /* from probe we allocate */ + nd_pfn->uuid = kmemdup(pfn_sb->uuid, 16, GFP_KERNEL); + if (!nd_pfn->uuid) + return -ENOMEM; + } else { + /* from init we validate */ + if (memcmp(nd_pfn->uuid, pfn_sb->uuid, 16) != 0) + return -EINVAL; + } + + /* + * 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. + */ + offset = le64_to_cpu(pfn_sb->dataoff); + nsio = to_nd_namespace_io(&ndns->dev); + if ((nsio->res.start + offset) & (ND_PFN_ALIGN - 1)) { + dev_err(&nd_pfn->dev, + "init failed: %s with offset %#llx not section aligned\n", + dev_name(&ndns->dev), offset); + return -EBUSY; + } else if (offset >= resource_size(&nsio->res)) { + dev_err(&nd_pfn->dev, "pfn array size exceeds capacity of %s\n", + dev_name(&ndns->dev)); + return -EBUSY; + } + + return 0; +} + +int nd_pfn_probe(struct nd_namespace_common *ndns, void *drvdata) +{ + int rc; + struct device *dev; + struct nd_pfn *nd_pfn; + struct nd_pfn_sb *pfn_sb; + struct nd_region *nd_region = to_nd_region(ndns->dev.parent); + + if (ndns->force_raw) + return -ENODEV; + + nvdimm_bus_lock(&ndns->dev); + dev = __nd_pfn_create(nd_region, NULL, PFN_MODE_NONE, ndns); + nvdimm_bus_unlock(&ndns->dev); + if (!dev) + return -ENOMEM; + dev_set_drvdata(dev, drvdata); + pfn_sb = kzalloc(sizeof(*pfn_sb), GFP_KERNEL); + nd_pfn = to_nd_pfn(dev); + nd_pfn->pfn_sb = pfn_sb; + rc = nd_pfn_validate(nd_pfn); + nd_pfn->pfn_sb = NULL; + kfree(pfn_sb); + dev_dbg(&ndns->dev, "%s: pfn: %s\n", __func__, + rc == 0 ? dev_name(dev) : "<none>"); + if (rc < 0) { + __nd_detach_ndns(dev, &nd_pfn->ndns); + put_device(dev); + } else + __nd_device_register(&nd_pfn->dev); + + return rc; +} +EXPORT_SYMBOL(nd_pfn_probe); |