path: root/drivers/nvdimm/namespace_devs.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.
 */
#include <linux/module.h>
#include <linux/device.h>
#include <linux/slab.h>
#include <linux/nd.h>
#include "nd-core.h"
#include "nd.h"

static void namespace_io_release(struct device *dev)
{
	struct nd_namespace_io *nsio = to_nd_namespace_io(dev);

	kfree(nsio);
}

static void namespace_pmem_release(struct device *dev)
{
	struct nd_namespace_pmem *nspm = to_nd_namespace_pmem(dev);

	kfree(nspm->alt_name);
	kfree(nspm->uuid);
	kfree(nspm);
}

static void namespace_blk_release(struct device *dev)
{
	struct nd_namespace_blk *nsblk = to_nd_namespace_blk(dev);
	struct nd_region *nd_region = to_nd_region(dev->parent);

	if (nsblk->id >= 0)
		ida_simple_remove(&nd_region->ns_ida, nsblk->id);
	kfree(nsblk->alt_name);
	kfree(nsblk->uuid);
	kfree(nsblk->res);
	kfree(nsblk);
}

static struct device_type namespace_io_device_type = {
	.name = "nd_namespace_io",
	.release = namespace_io_release,
};

static struct device_type namespace_pmem_device_type = {
	.name = "nd_namespace_pmem",
	.release = namespace_pmem_release,
};

static struct device_type namespace_blk_device_type = {
	.name = "nd_namespace_blk",
	.release = namespace_blk_release,
};

static bool is_namespace_pmem(struct device *dev)
{
	return dev ? dev->type == &namespace_pmem_device_type : false;
}

static bool is_namespace_blk(struct device *dev)
{
	return dev ? dev->type == &namespace_blk_device_type : false;
}

static bool is_namespace_io(struct device *dev)
{
	return dev ? dev->type == &namespace_io_device_type : false;
}

static ssize_t nstype_show(struct device *dev,
		struct device_attribute *attr, char *buf)
{
	struct nd_region *nd_region = to_nd_region(dev->parent);

	return sprintf(buf, "%d\n", nd_region_to_nstype(nd_region));
}
static DEVICE_ATTR_RO(nstype);

static ssize_t __alt_name_store(struct device *dev, const char *buf,
		const size_t len)
{
	char *input, *pos, *alt_name, **ns_altname;
	ssize_t rc;

	if (is_namespace_pmem(dev)) {
		struct nd_namespace_pmem *nspm = to_nd_namespace_pmem(dev);

		ns_altname = &nspm->alt_name;
	} else if (is_namespace_blk(dev)) {
		struct nd_namespace_blk *nsblk = to_nd_namespace_blk(dev);

		ns_altname = &nsblk->alt_name;
	} else
		return -ENXIO;

	if (dev->driver)
		return -EBUSY;

	input = kmemdup(buf, len + 1, GFP_KERNEL);
	if (!input)
		return -ENOMEM;

	input[len] = '\0';
	pos = strim(input);
	if (strlen(pos) + 1 > NSLABEL_NAME_LEN) {
		rc = -EINVAL;
		goto out;
	}

	alt_name = kzalloc(NSLABEL_NAME_LEN, GFP_KERNEL);
	if (!alt_name) {
		rc = -ENOMEM;
		goto out;
	}
	kfree(*ns_altname);
	*ns_altname = alt_name;
	sprintf(*ns_altname, "%s", pos);
	rc = len;

out:
	kfree(input);
	return rc;
}

static resource_size_t nd_namespace_blk_size(struct nd_namespace_blk *nsblk)
{
	struct nd_region *nd_region = to_nd_region(nsblk->dev.parent);
	struct nd_mapping *nd_mapping = &nd_region->mapping[0];
	struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
	struct nd_label_id label_id;
	resource_size_t size = 0;
	struct resource *res;

	if (!nsblk->uuid)
		return 0;
	nd_label_gen_id(&label_id, nsblk->uuid, NSLABEL_FLAG_LOCAL);
	for_each_dpa_resource(ndd, res)
		if (strcmp(res->name, label_id.id) == 0)
			size += resource_size(res);
	return size;
}

static int nd_namespace_label_update(struct nd_region *nd_region,
		struct device *dev)
{
	dev_WARN_ONCE(dev, dev->driver,
			"namespace must be idle during label update\n");
	if (dev->driver)
		return 0;

	/*
	 * Only allow label writes that will result in a valid namespace
	 * or deletion of an existing namespace.
	 */
	if (is_namespace_pmem(dev)) {
		struct nd_namespace_pmem *nspm = to_nd_namespace_pmem(dev);
		struct resource *res = &nspm->nsio.res;
		resource_size_t size = resource_size(res);

		if (size == 0 && nspm->uuid)
			/* delete allocation */;
		else if (!nspm->uuid)
			return 0;

		return nd_pmem_namespace_label_update(nd_region, nspm, size);
	} else if (is_namespace_blk(dev)) {
		/* TODO: implement blk labels */
		return 0;
	} else
		return -ENXIO;
}

static ssize_t alt_name_store(struct device *dev,
		struct device_attribute *attr, const char *buf, size_t len)
{
	struct nd_region *nd_region = to_nd_region(dev->parent);
	ssize_t rc;

	device_lock(dev);
	nvdimm_bus_lock(dev);
	wait_nvdimm_bus_probe_idle(dev);
	rc = __alt_name_store(dev, buf, len);
	if (rc >= 0)
		rc = nd_namespace_label_update(nd_region, dev);
	dev_dbg(dev, "%s: %s(%zd)\n", __func__, rc < 0 ? "fail " : "", rc);
	nvdimm_bus_unlock(dev