[deliverable/linux.git] / drivers / nvdimm / bus.c

/*
 * 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/fcntl.h>
#include <linux/async.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)
{
	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);
	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;

	device_unregister(dev);
	put_device(dev);
}

void nd_device_register(struct device *dev)
{
	dev->bus = &nvdimm_bus_type;
	device_initialize(dev);
	get_device(dev);
	async_schedule_domain(nd_async_device_register, dev,
			&nd_async_domain);
}
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);

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);

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);

static void wait_nvdimm_bus_probe_idle(struct nvdimm_bus *nvdimm_bus)
{
	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);

	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 (!access_ok(VERIFY_READ, p + in_len, in_size))
			return -EFAULT;
		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 (!access_ok(VERIFY_WRITE, p + in_len + out_len, out_size))
			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 (!access_ok(VERIFY_WRITE, p, sizeof(buf_len)))
		return -EFAULT;

	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))
		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);
}
Commit	Line	Data
45def22c DW	1	/*
	2	* Copyright(c) 2013-2015 Intel Corporation. All rights reserved.
	3	*
	4	* This program is free software; you can redistribute it and/or modify
	5	* it under the terms of version 2 of the GNU General Public License as
	6	* published by the Free Software Foundation.
	7	*
	8	* This program is distributed in the hope that it will be useful, but
	9	* WITHOUT ANY WARRANTY; without even the implied warranty of
	10	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	11	* General Public License for more details.
	12	*/
	13	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
62232e45	14	#include <linux/vmalloc.h>
45def22c	15	#include <linux/uaccess.h>
3d88002e	16	#include <linux/module.h>
45def22c	17	#include <linux/fcntl.h>
e6dfb2de	18	#include <linux/async.h>
62232e45	19	#include <linux/ndctl.h>
4d88a97a	20	#include <linux/sched.h>
45def22c DW	21	#include <linux/slab.h>
	22	#include <linux/fs.h>
	23	#include <linux/io.h>
62232e45	24	#include <linux/mm.h>
4d88a97a	25	#include <linux/nd.h>
45def22c	26	#include "nd-core.h"
4d88a97a	27	#include "nd.h"
45def22c	28
62232e45	29	int nvdimm_major;
45def22c DW	30	static int nvdimm_bus_major;
	31	static struct class *nd_class;
	32
4d88a97a DW	33	static int to_nd_device_type(struct device *dev)
	34	{
	35	if (is_nvdimm(dev))
	36	return ND_DEVICE_DIMM;
3d88002e DW	37	else if (is_nd_pmem(dev))
	38	return ND_DEVICE_REGION_PMEM;
	39	else if (is_nd_blk(dev))
	40	return ND_DEVICE_REGION_BLK;
	41	else if (is_nd_pmem(dev->parent) \|\| is_nd_blk(dev->parent))
	42	return nd_region_to_nstype(to_nd_region(dev->parent));
4d88a97a DW	43
	44	return 0;
	45	}
	46
	47	static int nvdimm_bus_uevent(struct device dev, struct kobj_uevent_env env)
	48	{
	49	return add_uevent_var(env, "MODALIAS=" ND_DEVICE_MODALIAS_FMT,
	50	to_nd_device_type(dev));
	51	}
	52
	53	static int nvdimm_bus_match(struct device dev, struct device_driver drv)
	54	{
	55	struct nd_device_driver *nd_drv = to_nd_device_driver(drv);
	56
	57	return test_bit(to_nd_device_type(dev), &nd_drv->type);
	58	}
	59
3d88002e DW	60	static struct module to_bus_provider(struct device dev)
	61	{
	62	/* pin bus providers while regions are enabled */
	63	if (is_nd_pmem(dev) \|\| is_nd_blk(dev)) {
	64	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
	65
	66	return nvdimm_bus->module;
	67	}
	68	return NULL;
	69	}
	70
eaf96153 DW	71	static void nvdimm_bus_probe_start(struct nvdimm_bus *nvdimm_bus)
	72	{
	73	nvdimm_bus_lock(&nvdimm_bus->dev);
	74	nvdimm_bus->probe_active++;
	75	nvdimm_bus_unlock(&nvdimm_bus->dev);
	76	}
	77
	78	static void nvdimm_bus_probe_end(struct nvdimm_bus *nvdimm_bus)
	79	{
	80	nvdimm_bus_lock(&nvdimm_bus->dev);
	81	if (--nvdimm_bus->probe_active == 0)
	82	wake_up(&nvdimm_bus->probe_wait);
	83	nvdimm_bus_unlock(&nvdimm_bus->dev);
	84	}
	85
4d88a97a DW	86	static int nvdimm_bus_probe(struct device *dev)
	87	{
	88	struct nd_device_driver *nd_drv = to_nd_device_driver(dev->driver);
3d88002e	89	struct module *provider = to_bus_provider(dev);
4d88a97a DW	90	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
	91	int rc;
	92
3d88002e DW	93	if (!try_module_get(provider))
	94	return -ENXIO;
	95
eaf96153	96	nvdimm_bus_probe_start(nvdimm_bus);
4d88a97a	97	rc = nd_drv->probe(dev);
eaf96153 DW	98	if (rc == 0)
	99	nd_region_probe_success(nvdimm_bus, dev);
	100	nvdimm_bus_probe_end(nvdimm_bus);
	101
4d88a97a DW	102	dev_dbg(&nvdimm_bus->dev, "%s.probe(%s) = %d\n", dev->driver->name,
4d88a97a DW	103	dev_name(dev), rc);
3d88002e DW	104	if (rc != 0)
3d88002e DW	105	module_put(provider);
4d88a97a DW	106	return rc;
	107	}
	108
	109	static int nvdimm_bus_remove(struct device *dev)
	110	{
	111	struct nd_device_driver *nd_drv = to_nd_device_driver(dev->driver);
3d88002e	112	struct module *provider = to_bus_provider(dev);
4d88a97a DW	113	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
	114	int rc;
	115
	116	rc = nd_drv->remove(dev);
eaf96153 DW	117	nd_region_disable(nvdimm_bus, dev);
eaf96153 DW	118
4d88a97a DW	119	dev_dbg(&nvdimm_bus->dev, "%s.remove(%s) = %d\n", dev->driver->name,
4d88a97a DW	120	dev_name(dev), rc);
3d88002e	121	module_put(provider);
4d88a97a DW	122	return rc;
	123	}
	124
	125	static struct bus_type nvdimm_bus_type = {
e6dfb2de	126	.name = "nd",
4d88a97a DW	127	.uevent = nvdimm_bus_uevent,
	128	.match = nvdimm_bus_match,
	129	.probe = nvdimm_bus_probe,
	130	.remove = nvdimm_bus_remove,
	131	};
	132
	133	static ASYNC_DOMAIN_EXCLUSIVE(nd_async_domain);
	134
	135	void nd_synchronize(void)
	136	{
	137	async_synchronize_full_domain(&nd_async_domain);
	138	}
	139	EXPORT_SYMBOL_GPL(nd_synchronize);
	140
	141	static void nd_async_device_register(void *d, async_cookie_t cookie)
	142	{
	143	struct device *dev = d;
	144
	145	if (device_add(dev) != 0) {
	146	dev_err(dev, "%s: failed\n", __func__);
	147	put_device(dev);
	148	}
	149	put_device(dev);
	150	}
	151
	152	static void nd_async_device_unregister(void *d, async_cookie_t cookie)
	153	{
	154	struct device *dev = d;
	155
	156	device_unregister(dev);
	157	put_device(dev);
	158	}
	159
	160	void nd_device_register(struct device *dev)
	161	{
	162	dev->bus = &nvdimm_bus_type;
	163	device_initialize(dev);
	164	get_device(dev);
	165	async_schedule_domain(nd_async_device_register, dev,
	166	&nd_async_domain);
	167	}
	168	EXPORT_SYMBOL(nd_device_register);
	169
	170	void nd_device_unregister(struct device *dev, enum nd_async_mode mode)
	171	{
	172	switch (mode) {
	173	case ND_ASYNC:
	174	get_device(dev);
	175	async_schedule_domain(nd_async_device_unregister, dev,
	176	&nd_async_domain);
	177	break;
	178	case ND_SYNC:
	179	nd_synchronize();
	180	device_unregister(dev);
	181	break;
	182	}
	183	}
	184	EXPORT_SYMBOL(nd_device_unregister);
	185
	186	/**
	187	* __nd_driver_register() - register a region or a namespace driver
	188	* @nd_drv: driver to register
	189	* @owner: automatically set by nd_driver_register() macro
	190	* @mod_name: automatically set by nd_driver_register() macro
191	*/
192	int __nd_driver_register(struct nd_device_driver nd_drv, struct module owner,
193	const char *mod_name)
194	{
195	struct device_driver *drv = &nd_drv->drv;
196
197	if (!nd_drv->type) {
198	pr_debug("driver type bitmask not set (%pf)\n",
199	__builtin_return_address(0));
200	return -EINVAL;
201	}
202
203	if (!nd_drv->probe \|\| !nd_drv->remove) {
204	pr_debug("->probe() and ->remove() must be specified\n");
205	return -EINVAL;
206	}
207
208	drv->bus = &nvdimm_bus_type;
209	drv->owner = owner;
210	drv->mod_name = mod_name;
211
212	return driver_register(drv);
213	}
214	EXPORT_SYMBOL(__nd_driver_register);
215
216	static ssize_t modalias_show(struct device dev, struct device_attribute attr,
217	char *buf)
218	{
219	return sprintf(buf, ND_DEVICE_MODALIAS_FMT "\n",
220	to_nd_device_type(dev));
221	}
222	static DEVICE_ATTR_RO(modalias);
223
224	static ssize_t devtype_show(struct device dev, struct device_attribute attr,
225	char *buf)
226	{
227	return sprintf(buf, "%s\n", dev->type->name);
228	}
229	static DEVICE_ATTR_RO(devtype);
230
231	static struct attribute *nd_device_attributes[] = {
232	&dev_attr_modalias.attr,
233	&dev_attr_devtype.attr,
234	NULL,
235	};
236
237	/**
238	* nd_device_attribute_group - generic attributes for all devices on an nd bus
239	*/
240	struct attribute_group nd_device_attribute_group = {
241	.attrs = nd_device_attributes,
e6dfb2de	242	};
4d88a97a	243	EXPORT_SYMBOL_GPL(nd_device_attribute_group);
e6dfb2de	244
45def22c DW	245	int nvdimm_bus_create_ndctl(struct nvdimm_bus *nvdimm_bus)
	246	{
	247	dev_t devt = MKDEV(nvdimm_bus_major, nvdimm_bus->id);
	248	struct device *dev;
	249
	250	dev = device_create(nd_class, &nvdimm_bus->dev, devt, nvdimm_bus,
	251	"ndctl%d", nvdimm_bus->id);
	252
	253	if (IS_ERR(dev)) {
	254	dev_dbg(&nvdimm_bus->dev, "failed to register ndctl%d: %ld\n",
	255	nvdimm_bus->id, PTR_ERR(dev));
	256	return PTR_ERR(dev);
	257	}
	258	return 0;
	259	}
	260
	261	void nvdimm_bus_destroy_ndctl(struct nvdimm_bus *nvdimm_bus)
	262	{
	263	device_destroy(nd_class, MKDEV(nvdimm_bus_major, nvdimm_bus->id));
	264	}
	265
62232e45 DW	266	static const struct nd_cmd_desc __nd_cmd_dimm_descs[] = {
	267	[ND_CMD_IMPLEMENTED] = { },
	268	[ND_CMD_SMART] = {
	269	.out_num = 2,
	270	.out_sizes = { 4, 8, },
	271	},
	272	[ND_CMD_SMART_THRESHOLD] = {
	273	.out_num = 2,
	274	.out_sizes = { 4, 8, },
	275	},
	276	[ND_CMD_DIMM_FLAGS] = {
	277	.out_num = 2,
	278	.out_sizes = { 4, 4 },
	279	},
	280	[ND_CMD_GET_CONFIG_SIZE] = {
	281	.out_num = 3,
	282	.out_sizes = { 4, 4, 4, },
	283	},
	284	[ND_CMD_GET_CONFIG_DATA] = {
	285	.in_num = 2,
	286	.in_sizes = { 4, 4, },
	287	.out_num = 2,
	288	.out_sizes = { 4, UINT_MAX, },
	289	},
	290	[ND_CMD_SET_CONFIG_DATA] = {
	291	.in_num = 3,
	292	.in_sizes = { 4, 4, UINT_MAX, },
	293	.out_num = 1,
	294	.out_sizes = { 4, },
	295	},
	296	[ND_CMD_VENDOR] = {
	297	.in_num = 3,
	298	.in_sizes = { 4, 4, UINT_MAX, },
	299	.out_num = 3,
	300	.out_sizes = { 4, 4, UINT_MAX, },
	301	},
	302	};
	303
	304	const struct nd_cmd_desc *nd_cmd_dimm_desc(int cmd)
	305	{
	306	if (cmd < ARRAY_SIZE(__nd_cmd_dimm_descs))
	307	return &__nd_cmd_dimm_descs[cmd];
	308	return NULL;
	309	}
	310	EXPORT_SYMBOL_GPL(nd_cmd_dimm_desc);
	311
	312	static const struct nd_cmd_desc __nd_cmd_bus_descs[] = {
	313	[ND_CMD_IMPLEMENTED] = { },
	314	[ND_CMD_ARS_CAP] = {
	315	.in_num = 2,
	316	.in_sizes = { 8, 8, },
	317	.out_num = 2,
	318	.out_sizes = { 4, 4, },
	319	},
	320	[ND_CMD_ARS_START] = {
	321	.in_num = 4,
	322	.in_sizes = { 8, 8, 2, 6, },
	323	.out_num = 1,
	324	.out_sizes = { 4, },
	325	},
	326	[ND_CMD_ARS_STATUS] = {
	327	.out_num = 2,
	328	.out_sizes = { 4, UINT_MAX, },
	329	},
330	};
331
332	const struct nd_cmd_desc *nd_cmd_bus_desc(int cmd)
333	{
334	if (cmd < ARRAY_SIZE(__nd_cmd_bus_descs))
335	return &__nd_cmd_bus_descs[cmd];
336	return NULL;
337	}
338	EXPORT_SYMBOL_GPL(nd_cmd_bus_desc);
339
340	u32 nd_cmd_in_size(struct nvdimm *nvdimm, int cmd,
341	const struct nd_cmd_desc desc, int idx, void buf)
342	{
343	if (idx >= desc->in_num)
344	return UINT_MAX;
345
346	if (desc->in_sizes[idx] < UINT_MAX)
347	return desc->in_sizes[idx];
348
349	if (nvdimm && cmd == ND_CMD_SET_CONFIG_DATA && idx == 2) {
350	struct nd_cmd_set_config_hdr *hdr = buf;
351
352	return hdr->in_length;
353	} else if (nvdimm && cmd == ND_CMD_VENDOR && idx == 2) {
354	struct nd_cmd_vendor_hdr *hdr = buf;
355
356	return hdr->in_length;
357	}
358
359	return UINT_MAX;
360	}
361	EXPORT_SYMBOL_GPL(nd_cmd_in_size);
362
363	u32 nd_cmd_out_size(struct nvdimm *nvdimm, int cmd,
364	const struct nd_cmd_desc desc, int idx, const u32 in_field,
365	const u32 *out_field)
366	{
367	if (idx >= desc->out_num)
368	return UINT_MAX;
369
370	if (desc->out_sizes[idx] < UINT_MAX)
371	return desc->out_sizes[idx];
372
373	if (nvdimm && cmd == ND_CMD_GET_CONFIG_DATA && idx == 1)
374	return in_field[1];
375	else if (nvdimm && cmd == ND_CMD_VENDOR && idx == 2)
376	return out_field[1];
377	else if (!nvdimm && cmd == ND_CMD_ARS_STATUS && idx == 1)
378	return ND_CMD_ARS_STATUS_MAX;
379
380	return UINT_MAX;
381	}
382	EXPORT_SYMBOL_GPL(nd_cmd_out_size);
383
eaf96153 DW	384	static void wait_nvdimm_bus_probe_idle(struct nvdimm_bus *nvdimm_bus)
	385	{
	386	do {
	387	if (nvdimm_bus->probe_active == 0)
	388	break;
	389	nvdimm_bus_unlock(&nvdimm_bus->dev);
	390	wait_event(nvdimm_bus->probe_wait,
	391	nvdimm_bus->probe_active == 0);
	392	nvdimm_bus_lock(&nvdimm_bus->dev);
	393	} while (true);
	394	}
	395
	396	/* set_config requires an idle interleave set */
	397	static int nd_cmd_clear_to_send(struct nvdimm *nvdimm, unsigned int cmd)
	398	{
	399	struct nvdimm_bus *nvdimm_bus;
	400
	401	if (!nvdimm \|\| cmd != ND_CMD_SET_CONFIG_DATA)
	402	return 0;
	403
	404	nvdimm_bus = walk_to_nvdimm_bus(&nvdimm->dev);
	405	wait_nvdimm_bus_probe_idle(nvdimm_bus);
	406
	407	if (atomic_read(&nvdimm->busy))
	408	return -EBUSY;
	409	return 0;
	410	}
	411
62232e45 DW	412	static int __nd_ioctl(struct nvdimm_bus nvdimm_bus, struct nvdimm nvdimm,
	413	int read_only, unsigned int ioctl_cmd, unsigned long arg)
	414	{
	415	struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc;
	416	size_t buf_len = 0, in_len = 0, out_len = 0;
	417	static char out_env[ND_CMD_MAX_ENVELOPE];
	418	static char in_env[ND_CMD_MAX_ENVELOPE];
	419	const struct nd_cmd_desc *desc = NULL;
	420	unsigned int cmd = _IOC_NR(ioctl_cmd);
	421	void __user p = (void __user ) arg;
	422	struct device *dev = &nvdimm_bus->dev;
	423	const char cmd_name, dimm_name;
	424	unsigned long dsm_mask;
	425	void *buf;
	426	int rc, i;
	427
	428	if (nvdimm) {
	429	desc = nd_cmd_dimm_desc(cmd);
	430	cmd_name = nvdimm_cmd_name(cmd);
	431	dsm_mask = nvdimm->dsm_mask ? *(nvdimm->dsm_mask) : 0;
	432	dimm_name = dev_name(&nvdimm->dev);
	433	} else {
	434	desc = nd_cmd_bus_desc(cmd);
	435	cmd_name = nvdimm_bus_cmd_name(cmd);
	436	dsm_mask = nd_desc->dsm_mask;
	437	dimm_name = "bus";
	438	}
	439
	440	if (!desc \|\| (desc->out_num + desc->in_num == 0) \|\|
	441	!test_bit(cmd, &dsm_mask))
	442	return -ENOTTY;
	443
	444	/* fail write commands (when read-only) */
	445	if (read_only)
	446	switch (ioctl_cmd) {
	447	case ND_IOCTL_VENDOR:
	448	case ND_IOCTL_SET_CONFIG_DATA:
	449	case ND_IOCTL_ARS_START:
	450	dev_dbg(&nvdimm_bus->dev, "'%s' command while read-only.\n",
	451	nvdimm ? nvdimm_cmd_name(cmd)
	452	: nvdimm_bus_cmd_name(cmd));
	453	return -EPERM;
	454	default:
	455	break;
	456	}
	457
	458	/* process an input envelope */
	459	for (i = 0; i < desc->in_num; i++) {
	460	u32 in_size, copy;
	461
	462	in_size = nd_cmd_in_size(nvdimm, cmd, desc, i, in_env);
	463	if (in_size == UINT_MAX) {
	464	dev_err(dev, "%s:%s unknown input size cmd: %s field: %d\n",
	465	__func__, dimm_name, cmd_name, i);
	466	return -ENXIO;
	467	}
	468	if (!access_ok(VERIFY_READ, p + in_len, in_size))
	469	return -EFAULT;
	470	if (in_len < sizeof(in_env))
	471	copy = min_t(u32, sizeof(in_env) - in_len, in_size);
	472	else
	473	copy = 0;
	474	if (copy && copy_from_user(&in_env[in_len], p + in_len, copy))
	475	return -EFAULT;
476	in_len += in_size;
477	}
478
479	/* process an output envelope */
480	for (i = 0; i < desc->out_num; i++) {
481	u32 out_size = nd_cmd_out_size(nvdimm, cmd, desc, i,
482	(u32 ) in_env, (u32 ) out_env);
483	u32 copy;
484
485	if (out_size == UINT_MAX) {
486	dev_dbg(dev, "%s:%s unknown output size cmd: %s field: %d\n",
487	__func__, dimm_name, cmd_name, i);
488	return -EFAULT;
489	}
490	if (!access_ok(VERIFY_WRITE, p + in_len + out_len, out_size))
491	return -EFAULT;
492	if (out_len < sizeof(out_env))
493	copy = min_t(u32, sizeof(out_env) - out_len, out_size);
494	else
495	copy = 0;
496	if (copy && copy_from_user(&out_env[out_len],
497	p + in_len + out_len, copy))
498	return -EFAULT;
499	out_len += out_size;
500	}
501
502	buf_len = out_len + in_len;
503	if (!access_ok(VERIFY_WRITE, p, sizeof(buf_len)))
504	return -EFAULT;
505
506	if (buf_len > ND_IOCTL_MAX_BUFLEN) {
507	dev_dbg(dev, "%s:%s cmd: %s buf_len: %zu > %d\n", __func__,
508	dimm_name, cmd_name, buf_len,
509	ND_IOCTL_MAX_BUFLEN);
510	return -EINVAL;
511	}
512
513	buf = vmalloc(buf_len);
514	if (!buf)
515	return -ENOMEM;
516
517	if (copy_from_user(buf, p, buf_len)) {
518	rc = -EFAULT;
519	goto out;
520	}
521
eaf96153 DW	522	nvdimm_bus_lock(&nvdimm_bus->dev);
	523	rc = nd_cmd_clear_to_send(nvdimm, cmd);
	524	if (rc)
	525	goto out_unlock;
	526
62232e45 DW	527	rc = nd_desc->ndctl(nd_desc, nvdimm, cmd, buf, buf_len);
62232e45 DW	528	if (rc < 0)
eaf96153	529	goto out_unlock;
62232e45 DW	530	if (copy_to_user(p, buf, buf_len))
62232e45 DW	531	rc = -EFAULT;
eaf96153 DW	532	out_unlock:
eaf96153 DW	533	nvdimm_bus_unlock(&nvdimm_bus->dev);
62232e45 DW	534	out:
	535	vfree(buf);
	536	return rc;
	537	}
	538
45def22c DW	539	static long nd_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
45def22c DW	540	{
62232e45 DW	541	long id = (long) file->private_data;
	542	int rc = -ENXIO, read_only;
	543	struct nvdimm_bus *nvdimm_bus;
	544
	545	read_only = (O_RDWR != (file->f_flags & O_ACCMODE));
	546	mutex_lock(&nvdimm_bus_list_mutex);
	547	list_for_each_entry(nvdimm_bus, &nvdimm_bus_list, list) {
	548	if (nvdimm_bus->id == id) {
	549	rc = __nd_ioctl(nvdimm_bus, NULL, read_only, cmd, arg);
	550	break;
	551	}
	552	}
	553	mutex_unlock(&nvdimm_bus_list_mutex);
	554
	555	return rc;
	556	}
	557
	558	static int match_dimm(struct device dev, void data)
	559	{
	560	long id = (long) data;
	561
	562	if (is_nvdimm(dev)) {
	563	struct nvdimm *nvdimm = to_nvdimm(dev);
	564
	565	return nvdimm->id == id;
	566	}
	567
	568	return 0;
	569	}
	570
	571	static long nvdimm_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
	572	{
	573	int rc = -ENXIO, read_only;
	574	struct nvdimm_bus *nvdimm_bus;
	575
	576	read_only = (O_RDWR != (file->f_flags & O_ACCMODE));
	577	mutex_lock(&nvdimm_bus_list_mutex);
	578	list_for_each_entry(nvdimm_bus, &nvdimm_bus_list, list) {
	579	struct device *dev = device_find_child(&nvdimm_bus->dev,
	580	file->private_data, match_dimm);
	581	struct nvdimm *nvdimm;
	582
	583	if (!dev)
	584	continue;
	585
	586	nvdimm = to_nvdimm(dev);
	587	rc = __nd_ioctl(nvdimm_bus, nvdimm, read_only, cmd, arg);
	588	put_device(dev);
	589	break;
	590	}
	591	mutex_unlock(&nvdimm_bus_list_mutex);
	592
	593	return rc;
	594	}
	595
	596	static int nd_open(struct inode inode, struct file file)
	597	{
	598	long minor = iminor(inode);
	599
	600	file->private_data = (void *) minor;
	601	return 0;
45def22c DW	602	}
	603
	604	static const struct file_operations nvdimm_bus_fops = {
	605	.owner = THIS_MODULE,
62232e45	606	.open = nd_open,
45def22c DW	607	.unlocked_ioctl = nd_ioctl,
	608	.compat_ioctl = nd_ioctl,
	609	.llseek = noop_llseek,
	610	};
	611
62232e45 DW	612	static const struct file_operations nvdimm_fops = {
	613	.owner = THIS_MODULE,
	614	.open = nd_open,
	615	.unlocked_ioctl = nvdimm_ioctl,
	616	.compat_ioctl = nvdimm_ioctl,
	617	.llseek = noop_llseek,
	618	};
	619
45def22c DW	620	int __init nvdimm_bus_init(void)
	621	{
	622	int rc;
	623
e6dfb2de DW	624	rc = bus_register(&nvdimm_bus_type);
	625	if (rc)
	626	return rc;
	627
45def22c DW	628	rc = register_chrdev(0, "ndctl", &nvdimm_bus_fops);
45def22c DW	629	if (rc < 0)
62232e45	630	goto err_bus_chrdev;
45def22c DW	631	nvdimm_bus_major = rc;
45def22c DW	632
62232e45 DW	633	rc = register_chrdev(0, "dimmctl", &nvdimm_fops);
	634	if (rc < 0)
	635	goto err_dimm_chrdev;
	636	nvdimm_major = rc;
	637
45def22c DW	638	nd_class = class_create(THIS_MODULE, "nd");
	639	if (IS_ERR(nd_class))
	640	goto err_class;
	641
	642	return 0;
	643
	644	err_class:
62232e45 DW	645	unregister_chrdev(nvdimm_major, "dimmctl");
62232e45 DW	646	err_dimm_chrdev:
45def22c	647	unregister_chrdev(nvdimm_bus_major, "ndctl");
62232e45	648	err_bus_chrdev:
e6dfb2de	649	bus_unregister(&nvdimm_bus_type);
45def22c DW	650
	651	return rc;
	652	}
	653
4d88a97a	654	void nvdimm_bus_exit(void)
45def22c DW	655	{
	656	class_destroy(nd_class);
	657	unregister_chrdev(nvdimm_bus_major, "ndctl");
62232e45	658	unregister_chrdev(nvdimm_major, "dimmctl");
e6dfb2de	659	bus_unregister(&nvdimm_bus_type);
45def22c	660	}