diff options
Diffstat (limited to 'drivers/nvdimm/bus.c')
-rw-r--r-- | drivers/nvdimm/bus.c | 725 |
1 files changed, 725 insertions, 0 deletions
diff --git a/drivers/nvdimm/bus.c b/drivers/nvdimm/bus.c new file mode 100644 index 000000000..7e2c43f70 --- /dev/null +++ b/drivers/nvdimm/bus.c @@ -0,0 +1,725 @@ +/* + * 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. + */ +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt +#include <linux/vmalloc.h> +#include <linux/uaccess.h> +#include <linux/module.h> +#include <linux/blkdev.h> +#include <linux/fcntl.h> +#include <linux/async.h> +#include <linux/genhd.h> +#include <linux/ndctl.h> +#include <linux/sched.h> +#include <linux/slab.h> +#include <linux/fs.h> +#include <linux/io.h> +#include <linux/mm.h> +#include <linux/nd.h> +#include "nd-core.h" +#include "nd.h" + +int nvdimm_major; +static int nvdimm_bus_major; +static struct class *nd_class; + +static int to_nd_device_type(struct device *dev) +{ + if (is_nvdimm(dev)) + return ND_DEVICE_DIMM; + else if (is_nd_pmem(dev)) + return ND_DEVICE_REGION_PMEM; + else if (is_nd_blk(dev)) + return ND_DEVICE_REGION_BLK; + else if (is_nd_pmem(dev->parent) || is_nd_blk(dev->parent)) + return nd_region_to_nstype(to_nd_region(dev->parent)); + + return 0; +} + +static int nvdimm_bus_uevent(struct device *dev, struct kobj_uevent_env *env) +{ + /* + * Ensure that region devices always have their numa node set as + * early as possible. + */ + if (is_nd_pmem(dev) || is_nd_blk(dev)) + set_dev_node(dev, to_nd_region(dev)->numa_node); + return add_uevent_var(env, "MODALIAS=" ND_DEVICE_MODALIAS_FMT, + to_nd_device_type(dev)); +} + +static int nvdimm_bus_match(struct device *dev, struct device_driver *drv) +{ + struct nd_device_driver *nd_drv = to_nd_device_driver(drv); + + return test_bit(to_nd_device_type(dev), &nd_drv->type); +} + +static struct module *to_bus_provider(struct device *dev) +{ + /* pin bus providers while regions are enabled */ + if (is_nd_pmem(dev) || is_nd_blk(dev)) { + struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev); + + return nvdimm_bus->module; + } + 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); + struct module *provider = to_bus_provider(dev); + struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev); + int rc; + + 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); + else + nd_region_disable(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) + module_put(provider); + return rc; +} + +static int nvdimm_bus_remove(struct device *dev) +{ + struct nd_device_driver *nd_drv = to_nd_device_driver(dev->driver); + struct module *provider = to_bus_provider(dev); + struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(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); + return rc; +} + +static struct bus_type nvdimm_bus_type = { + .name = "nd", + .uevent = nvdimm_bus_uevent, + .match = nvdimm_bus_match, + .probe = nvdimm_bus_probe, + .remove = nvdimm_bus_remove, +}; + +static ASYNC_DOMAIN_EXCLUSIVE(nd_async_domain); + +void nd_synchronize(void) +{ + async_synchronize_full_domain(&nd_async_domain); +} +EXPORT_SYMBOL_GPL(nd_synchronize); + +static void nd_async_device_register(void *d, async_cookie_t cookie) +{ + struct device *dev = d; + + if (device_add(dev) != 0) { + dev_err(dev, "%s: failed\n", __func__); + put_device(dev); + } + put_device(dev); +} + +static void nd_async_device_unregister(void *d, async_cookie_t cookie) +{ + struct device *dev = d; + + /* flush bus operations before delete */ + nvdimm_bus_lock(dev); + nvdimm_bus_unlock(dev); + + device_unregister(dev); + put_device(dev); +} + +void __nd_device_register(struct device *dev) +{ + dev->bus = &nvdimm_bus_type; + get_device(dev); + async_schedule_domain(nd_async_device_register, dev, + &nd_async_domain); +} + +void nd_device_register(struct device *dev) +{ + device_initialize(dev); + __nd_device_register(dev); +} +EXPORT_SYMBOL(nd_device_register); + +void nd_device_unregister(struct device *dev, enum nd_async_mode mode) +{ + switch (mode) { + case ND_ASYNC: + get_device(dev); + async_schedule_domain(nd_async_device_unregister, dev, + &nd_async_domain); + break; + case ND_SYNC: + nd_synchronize(); + device_unregister(dev); + break; + } +} +EXPORT_SYMBOL(nd_device_unregister); + +/** + * __nd_driver_register() - register a region or a namespace driver + * @nd_drv: driver to register + * @owner: automatically set by nd_driver_register() macro + * @mod_name: automatically set by nd_driver_register() macro + */ +int __nd_driver_register(struct nd_device_driver *nd_drv, struct module *owner, + const char *mod_name) +{ + struct device_driver *drv = &nd_drv->drv; + + if (!nd_drv->type) { + pr_debug("driver type bitmask not set (%pf)\n", + __builtin_return_address(0)); + return -EINVAL; + } + + if (!nd_drv->probe || !nd_drv->remove) { + pr_debug("->probe() and ->remove() must be specified\n"); + return -EINVAL; + } + + drv->bus = &nvdimm_bus_type; + drv->owner = owner; + drv->mod_name = mod_name; + + return driver_register(drv); +} +EXPORT_SYMBOL(__nd_driver_register); + +int nvdimm_revalidate_disk(struct gendisk *disk) +{ + struct device *dev = disk->driverfs_dev; + struct nd_region *nd_region = to_nd_region(dev->parent); + const char *pol = nd_region->ro ? "only" : "write"; + + if (nd_region->ro == get_disk_ro(disk)) + return 0; + + dev_info(dev, "%s read-%s, marking %s read-%s\n", + dev_name(&nd_region->dev), pol, disk->disk_name, pol); + set_disk_ro(disk, nd_region->ro); + + return 0; + +} +EXPORT_SYMBOL(nvdimm_revalidate_disk); + +static ssize_t modalias_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + return sprintf(buf, ND_DEVICE_MODALIAS_FMT "\n", + to_nd_device_type(dev)); +} +static DEVICE_ATTR_RO(modalias); + +static ssize_t devtype_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + return sprintf(buf, "%s\n", dev->type->name); +} +static DEVICE_ATTR_RO(devtype); + +static struct attribute *nd_device_attributes[] = { + &dev_attr_modalias.attr, + &dev_attr_devtype.attr, + NULL, +}; + +/** + * nd_device_attribute_group - generic attributes for all devices on an nd bus + */ +struct attribute_group nd_device_attribute_group = { + .attrs = nd_device_attributes, +}; +EXPORT_SYMBOL_GPL(nd_device_attribute_group); + +static ssize_t numa_node_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return sprintf(buf, "%d\n", dev_to_node(dev)); +} +static DEVICE_ATTR_RO(numa_node); + +static struct attribute *nd_numa_attributes[] = { + &dev_attr_numa_node.attr, + NULL, +}; + +static umode_t nd_numa_attr_visible(struct kobject *kobj, struct attribute *a, + int n) +{ + if (!IS_ENABLED(CONFIG_NUMA)) + return 0; + + return a->mode; +} + +/** + * nd_numa_attribute_group - NUMA attributes for all devices on an nd bus + */ +struct attribute_group nd_numa_attribute_group = { + .attrs = nd_numa_attributes, + .is_visible = nd_numa_attr_visible, +}; +EXPORT_SYMBOL_GPL(nd_numa_attribute_group); + +int nvdimm_bus_create_ndctl(struct nvdimm_bus *nvdimm_bus) +{ + dev_t devt = MKDEV(nvdimm_bus_major, nvdimm_bus->id); + struct device *dev; + + dev = device_create(nd_class, &nvdimm_bus->dev, devt, nvdimm_bus, + "ndctl%d", nvdimm_bus->id); + + if (IS_ERR(dev)) { + dev_dbg(&nvdimm_bus->dev, "failed to register ndctl%d: %ld\n", + nvdimm_bus->id, PTR_ERR(dev)); + return PTR_ERR(dev); + } + return 0; +} + +void nvdimm_bus_destroy_ndctl(struct nvdimm_bus *nvdimm_bus) +{ + device_destroy(nd_class, MKDEV(nvdimm_bus_major, nvdimm_bus->id)); +} + +static const struct nd_cmd_desc __nd_cmd_dimm_descs[] = { + [ND_CMD_IMPLEMENTED] = { }, + [ND_CMD_SMART] = { + .out_num = 2, + .out_sizes = { 4, 8, }, + }, + [ND_CMD_SMART_THRESHOLD] = { + .out_num = 2, + .out_sizes = { 4, 8, }, + }, + [ND_CMD_DIMM_FLAGS] = { + .out_num = 2, + .out_sizes = { 4, 4 }, + }, + [ND_CMD_GET_CONFIG_SIZE] = { + .out_num = 3, + .out_sizes = { 4, 4, 4, }, + }, + [ND_CMD_GET_CONFIG_DATA] = { + .in_num = 2, + .in_sizes = { 4, 4, }, + .out_num = 2, + .out_sizes = { 4, UINT_MAX, }, + }, + [ND_CMD_SET_CONFIG_DATA] = { + .in_num = 3, + .in_sizes = { 4, 4, UINT_MAX, }, + .out_num = 1, + .out_sizes = { 4, }, + }, + [ND_CMD_VENDOR] = { + .in_num = 3, + .in_sizes = { 4, 4, UINT_MAX, }, + .out_num = 3, + .out_sizes = { 4, 4, UINT_MAX, }, + }, +}; + +const struct nd_cmd_desc *nd_cmd_dimm_desc(int cmd) +{ + if (cmd < ARRAY_SIZE(__nd_cmd_dimm_descs)) + return &__nd_cmd_dimm_descs[cmd]; + return NULL; +} +EXPORT_SYMBOL_GPL(nd_cmd_dimm_desc); + +static const struct nd_cmd_desc __nd_cmd_bus_descs[] = { + [ND_CMD_IMPLEMENTED] = { }, + [ND_CMD_ARS_CAP] = { + .in_num = 2, + .in_sizes = { 8, 8, }, + .out_num = 2, + .out_sizes = { 4, 4, }, + }, + [ND_CMD_ARS_START] = { + .in_num = 4, + .in_sizes = { 8, 8, 2, 6, }, + .out_num = 1, + .out_sizes = { 4, }, + }, + [ND_CMD_ARS_STATUS] = { + .out_num = 2, + .out_sizes = { 4, UINT_MAX, }, + }, +}; + +const struct nd_cmd_desc *nd_cmd_bus_desc(int cmd) +{ + if (cmd < ARRAY_SIZE(__nd_cmd_bus_descs)) + return &__nd_cmd_bus_descs[cmd]; + return NULL; +} +EXPORT_SYMBOL_GPL(nd_cmd_bus_desc); + +u32 nd_cmd_in_size(struct nvdimm *nvdimm, int cmd, + const struct nd_cmd_desc *desc, int idx, void *buf) +{ + if (idx >= desc->in_num) + return UINT_MAX; + + if (desc->in_sizes[idx] < UINT_MAX) + return desc->in_sizes[idx]; + + if (nvdimm && cmd == ND_CMD_SET_CONFIG_DATA && idx == 2) { + struct nd_cmd_set_config_hdr *hdr = buf; + + return hdr->in_length; + } else if (nvdimm && cmd == ND_CMD_VENDOR && idx == 2) { + struct nd_cmd_vendor_hdr *hdr = buf; + + return hdr->in_length; + } + + return UINT_MAX; +} +EXPORT_SYMBOL_GPL(nd_cmd_in_size); + +u32 nd_cmd_out_size(struct nvdimm *nvdimm, int cmd, + const struct nd_cmd_desc *desc, int idx, const u32 *in_field, + const u32 *out_field) +{ + if (idx >= desc->out_num) + return UINT_MAX; + + if (desc->out_sizes[idx] < UINT_MAX) + return desc->out_sizes[idx]; + + if (nvdimm && cmd == ND_CMD_GET_CONFIG_DATA && idx == 1) + return in_field[1]; + else if (nvdimm && cmd == ND_CMD_VENDOR && idx == 2) + return out_field[1]; + else if (!nvdimm && cmd == ND_CMD_ARS_STATUS && idx == 1) + return ND_CMD_ARS_STATUS_MAX; + + return UINT_MAX; +} +EXPORT_SYMBOL_GPL(nd_cmd_out_size); + +void wait_nvdimm_bus_probe_idle(struct device *dev) +{ + struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev); + + 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->dev); + + 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) +{ + struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc; + size_t buf_len = 0, in_len = 0, out_len = 0; + static char out_env[ND_CMD_MAX_ENVELOPE]; + static char in_env[ND_CMD_MAX_ENVELOPE]; + const struct nd_cmd_desc *desc = NULL; + unsigned int cmd = _IOC_NR(ioctl_cmd); + void __user *p = (void __user *) arg; + struct device *dev = &nvdimm_bus->dev; + const char *cmd_name, *dimm_name; + unsigned long dsm_mask; + void *buf; + int rc, i; + + if (nvdimm) { + desc = nd_cmd_dimm_desc(cmd); + cmd_name = nvdimm_cmd_name(cmd); + dsm_mask = nvdimm->dsm_mask ? *(nvdimm->dsm_mask) : 0; + dimm_name = dev_name(&nvdimm->dev); + } else { + desc = nd_cmd_bus_desc(cmd); + cmd_name = nvdimm_bus_cmd_name(cmd); + dsm_mask = nd_desc->dsm_mask; + dimm_name = "bus"; + } + + if (!desc || (desc->out_num + desc->in_num == 0) || + !test_bit(cmd, &dsm_mask)) + return -ENOTTY; + + /* fail write commands (when read-only) */ + if (read_only) + switch (ioctl_cmd) { + case ND_IOCTL_VENDOR: + case ND_IOCTL_SET_CONFIG_DATA: + case ND_IOCTL_ARS_START: + dev_dbg(&nvdimm_bus->dev, "'%s' command while read-only.\n", + nvdimm ? nvdimm_cmd_name(cmd) + : nvdimm_bus_cmd_name(cmd)); + return -EPERM; + default: + break; + } + + /* process an input envelope */ + for (i = 0; i < desc->in_num; i++) { + u32 in_size, copy; + + in_size = nd_cmd_in_size(nvdimm, cmd, desc, i, in_env); + if (in_size == UINT_MAX) { + dev_err(dev, "%s:%s unknown input size cmd: %s field: %d\n", + __func__, dimm_name, cmd_name, i); + return -ENXIO; + } + if (in_len < sizeof(in_env)) + copy = min_t(u32, sizeof(in_env) - in_len, in_size); + else + copy = 0; + if (copy && copy_from_user(&in_env[in_len], p + in_len, copy)) + return -EFAULT; + in_len += in_size; + } + + /* process an output envelope */ + for (i = 0; i < desc->out_num; i++) { + u32 out_size = nd_cmd_out_size(nvdimm, cmd, desc, i, + (u32 *) in_env, (u32 *) out_env); + u32 copy; + + if (out_size == UINT_MAX) { + dev_dbg(dev, "%s:%s unknown output size cmd: %s field: %d\n", + __func__, dimm_name, cmd_name, i); + return -EFAULT; + } + if (out_len < sizeof(out_env)) + copy = min_t(u32, sizeof(out_env) - out_len, out_size); + else + copy = 0; + if (copy && copy_from_user(&out_env[out_len], + p + in_len + out_len, copy)) + return -EFAULT; + out_len += out_size; + } + + buf_len = out_len + in_len; + if (buf_len > ND_IOCTL_MAX_BUFLEN) { + dev_dbg(dev, "%s:%s cmd: %s buf_len: %zu > %d\n", __func__, + dimm_name, cmd_name, buf_len, + ND_IOCTL_MAX_BUFLEN); + return -EINVAL; + } + + buf = vmalloc(buf_len); + if (!buf) + return -ENOMEM; + + if (copy_from_user(buf, p, buf_len)) { + rc = -EFAULT; + 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_unlock; + if (copy_to_user(p, buf, buf_len)) + rc = -EFAULT; + out_unlock: + nvdimm_bus_unlock(&nvdimm_bus->dev); + out: + vfree(buf); + return rc; +} + +static long nd_ioctl(struct file *file, unsigned int cmd, unsigned long arg) +{ + long id = (long) file->private_data; + int rc = -ENXIO, read_only; + struct nvdimm_bus *nvdimm_bus; + + read_only = (O_RDWR != (file->f_flags & O_ACCMODE)); + mutex_lock(&nvdimm_bus_list_mutex); + list_for_each_entry(nvdimm_bus, &nvdimm_bus_list, list) { + if (nvdimm_bus->id == id) { + rc = __nd_ioctl(nvdimm_bus, NULL, read_only, cmd, arg); + break; + } + } + mutex_unlock(&nvdimm_bus_list_mutex); + + return rc; +} + +static int match_dimm(struct device *dev, void *data) +{ + long id = (long) data; + + if (is_nvdimm(dev)) { + struct nvdimm *nvdimm = to_nvdimm(dev); + + return nvdimm->id == id; + } + + return 0; +} + +static long nvdimm_ioctl(struct file *file, unsigned int cmd, unsigned long arg) +{ + int rc = -ENXIO, read_only; + struct nvdimm_bus *nvdimm_bus; + + read_only = (O_RDWR != (file->f_flags & O_ACCMODE)); + mutex_lock(&nvdimm_bus_list_mutex); + list_for_each_entry(nvdimm_bus, &nvdimm_bus_list, list) { + struct device *dev = device_find_child(&nvdimm_bus->dev, + file->private_data, match_dimm); + struct nvdimm *nvdimm; + + if (!dev) + continue; + + nvdimm = to_nvdimm(dev); + rc = __nd_ioctl(nvdimm_bus, nvdimm, read_only, cmd, arg); + put_device(dev); + break; + } + mutex_unlock(&nvdimm_bus_list_mutex); + + return rc; +} + +static int nd_open(struct inode *inode, struct file *file) +{ + long minor = iminor(inode); + + file->private_data = (void *) minor; + return 0; +} + +static const struct file_operations nvdimm_bus_fops = { + .owner = THIS_MODULE, + .open = nd_open, + .unlocked_ioctl = nd_ioctl, + .compat_ioctl = nd_ioctl, + .llseek = noop_llseek, +}; + +static const struct file_operations nvdimm_fops = { + .owner = THIS_MODULE, + .open = nd_open, + .unlocked_ioctl = nvdimm_ioctl, + .compat_ioctl = nvdimm_ioctl, + .llseek = noop_llseek, +}; + +int __init nvdimm_bus_init(void) +{ + int rc; + + rc = bus_register(&nvdimm_bus_type); + if (rc) + return rc; + + rc = register_chrdev(0, "ndctl", &nvdimm_bus_fops); + if (rc < 0) + goto err_bus_chrdev; + nvdimm_bus_major = rc; + + rc = register_chrdev(0, "dimmctl", &nvdimm_fops); + if (rc < 0) + goto err_dimm_chrdev; + nvdimm_major = rc; + + nd_class = class_create(THIS_MODULE, "nd"); + if (IS_ERR(nd_class)) { + rc = PTR_ERR(nd_class); + goto err_class; + } + + return 0; + + err_class: + unregister_chrdev(nvdimm_major, "dimmctl"); + err_dimm_chrdev: + unregister_chrdev(nvdimm_bus_major, "ndctl"); + err_bus_chrdev: + bus_unregister(&nvdimm_bus_type); + + return rc; +} + +void nvdimm_bus_exit(void) +{ + class_destroy(nd_class); + unregister_chrdev(nvdimm_bus_major, "ndctl"); + unregister_chrdev(nvdimm_major, "dimmctl"); + bus_unregister(&nvdimm_bus_type); +} |