[deliverable/linux.git] / drivers / nvdimm / region.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/cpumask.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/nd.h>
#include "nd.h"

static int nd_region_probe(struct device *dev)
{
	int err, rc;
	static unsigned long once;
	struct nd_region_data *ndrd;
	struct nd_region *nd_region = to_nd_region(dev);

	if (nd_region->num_lanes > num_online_cpus()
			&& nd_region->num_lanes < num_possible_cpus()
			&& !test_and_set_bit(0, &once)) {
		dev_info(dev, "online cpus (%d) < concurrent i/o lanes (%d) < possible cpus (%d)\n",
				num_online_cpus(), nd_region->num_lanes,
				num_possible_cpus());
		dev_info(dev, "setting nr_cpus=%d may yield better libnvdimm device performance\n",
				nd_region->num_lanes);
	}

	rc = nd_region_activate(nd_region);
	if (rc)
		return rc;

	rc = nd_blk_region_init(nd_region);
	if (rc)
		return rc;

	rc = nd_region_register_namespaces(nd_region, &err);
	if (rc < 0)
		return rc;

	ndrd = dev_get_drvdata(dev);
	ndrd->ns_active = rc;
	ndrd->ns_count = rc + err;

	if (rc && err && rc == err)
		return -ENODEV;

	nd_region->btt_seed = nd_btt_create(nd_region);
	nd_region->pfn_seed = nd_pfn_create(nd_region);
	nd_region->dax_seed = nd_dax_create(nd_region);
	if (err == 0)
		return 0;

	/*
	 * Given multiple namespaces per region, we do not want to
	 * disable all the successfully registered peer namespaces upon
	 * a single registration failure.  If userspace is missing a
	 * namespace that it expects it can disable/re-enable the region
	 * to retry discovery after correcting the failure.
	 * <regionX>/namespaces returns the current
	 * "<async-registered>/<total>" namespace count.
	 */
	dev_err(dev, "failed to register %d namespace%s, continuing...\n",
			err, err == 1 ? "" : "s");
	return 0;
}

static int child_unregister(struct device *dev, void *data)
{
	nd_device_unregister(dev, ND_SYNC);
	return 0;
}

static int nd_region_remove(struct device *dev)
{
	struct nd_region *nd_region = to_nd_region(dev);

	device_for_each_child(dev, NULL, child_unregister);

	/* flush attribute readers and disable */
	nvdimm_bus_lock(dev);
	nd_region->ns_seed = NULL;
	nd_region->btt_seed = NULL;
	nd_region->pfn_seed = NULL;
	nd_region->dax_seed = NULL;
	dev_set_drvdata(dev, NULL);
	nvdimm_bus_unlock(dev);

	return 0;
}

static int child_notify(struct device *dev, void *data)
{
	nd_device_notify(dev, *(enum nvdimm_event *) data);
	return 0;
}

static void nd_region_notify(struct device *dev, enum nvdimm_event event)
{
	device_for_each_child(dev, &event, child_notify);
}

static struct nd_device_driver nd_region_driver = {
	.probe = nd_region_probe,
	.remove = nd_region_remove,
	.notify = nd_region_notify,
	.drv = {
		.name = "nd_region",
	},
	.type = ND_DRIVER_REGION_BLK | ND_DRIVER_REGION_PMEM,
};

int __init nd_region_init(void)
{
	return nd_driver_register(&nd_region_driver);
}

void nd_region_exit(void)
{
	driver_unregister(&nd_region_driver.drv);
}

MODULE_ALIAS_ND_DEVICE(ND_DEVICE_REGION_PMEM);
MODULE_ALIAS_ND_DEVICE(ND_DEVICE_REGION_BLK);
Commit	Line	Data
3d88002e 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	*/
5212e11f	13	#include <linux/cpumask.h>
3d88002e DW	14	#include <linux/module.h>
	15	#include <linux/device.h>
	16	#include <linux/nd.h>
	17	#include "nd.h"
	18
	19	static int nd_region_probe(struct device *dev)
	20	{
047fc8a1	21	int err, rc;
5212e11f	22	static unsigned long once;
e5ae3b25	23	struct nd_region_data *ndrd;
3d88002e	24	struct nd_region *nd_region = to_nd_region(dev);
3d88002e	25
5212e11f VV	26	if (nd_region->num_lanes > num_online_cpus()
	27	&& nd_region->num_lanes < num_possible_cpus()
	28	&& !test_and_set_bit(0, &once)) {
	29	dev_info(dev, "online cpus (%d) < concurrent i/o lanes (%d) < possible cpus (%d)\n",
	30	num_online_cpus(), nd_region->num_lanes,
	31	num_possible_cpus());
	32	dev_info(dev, "setting nr_cpus=%d may yield better libnvdimm device performance\n",
	33	nd_region->num_lanes);
	34	}
	35
e5ae3b25 DW	36	rc = nd_region_activate(nd_region);
	37	if (rc)
	38	return rc;
	39
047fc8a1 RZ	40	rc = nd_blk_region_init(nd_region);
	41	if (rc)
	42	return rc;
	43
	44	rc = nd_region_register_namespaces(nd_region, &err);
3d88002e DW	45	if (rc < 0)
	46	return rc;
	47
e5ae3b25 DW	48	ndrd = dev_get_drvdata(dev);
	49	ndrd->ns_active = rc;
	50	ndrd->ns_count = rc + err;
3d88002e	51
8c2f7e86 DW	52	if (rc && err && rc == err)
	53	return -ENODEV;
	54
	55	nd_region->btt_seed = nd_btt_create(nd_region);
e1455744	56	nd_region->pfn_seed = nd_pfn_create(nd_region);
cd03412a	57	nd_region->dax_seed = nd_dax_create(nd_region);
3d88002e DW	58	if (err == 0)
	59	return 0;
	60
3d88002e DW	61	/*
	62	* Given multiple namespaces per region, we do not want to
	63	* disable all the successfully registered peer namespaces upon
	64	* a single registration failure. If userspace is missing a
	65	* namespace that it expects it can disable/re-enable the region
	66	* to retry discovery after correcting the failure.
	67	* <regionX>/namespaces returns the current
	68	* "<async-registered>/<total>" namespace count.
	69	*/
	70	dev_err(dev, "failed to register %d namespace%s, continuing...\n",
	71	err, err == 1 ? "" : "s");
	72	return 0;
	73	}
	74
	75	static int child_unregister(struct device dev, void data)
	76	{
	77	nd_device_unregister(dev, ND_SYNC);
	78	return 0;
	79	}
	80
	81	static int nd_region_remove(struct device *dev)
	82	{
bf9bccc1 DW	83	struct nd_region *nd_region = to_nd_region(dev);
bf9bccc1 DW	84
a8f72022 DW	85	device_for_each_child(dev, NULL, child_unregister);
a8f72022 DW	86
3d88002e DW	87	/* flush attribute readers and disable */
3d88002e DW	88	nvdimm_bus_lock(dev);
bf9bccc1	89	nd_region->ns_seed = NULL;
8c2f7e86	90	nd_region->btt_seed = NULL;
e1455744	91	nd_region->pfn_seed = NULL;
cd03412a	92	nd_region->dax_seed = NULL;
3d88002e DW	93	dev_set_drvdata(dev, NULL);
	94	nvdimm_bus_unlock(dev);
	95
3d88002e DW	96	return 0;
	97	}
	98
71999466 DW	99	static int child_notify(struct device dev, void data)
	100	{
	101	nd_device_notify(dev, (enum nvdimm_event ) data);
	102	return 0;
	103	}
	104
	105	static void nd_region_notify(struct device *dev, enum nvdimm_event event)
	106	{
	107	device_for_each_child(dev, &event, child_notify);
	108	}
	109
3d88002e DW	110	static struct nd_device_driver nd_region_driver = {
	111	.probe = nd_region_probe,
	112	.remove = nd_region_remove,
71999466	113	.notify = nd_region_notify,
3d88002e DW	114	.drv = {
	115	.name = "nd_region",
	116	},
	117	.type = ND_DRIVER_REGION_BLK \| ND_DRIVER_REGION_PMEM,
	118	};
	119
	120	int __init nd_region_init(void)
	121	{
	122	return nd_driver_register(&nd_region_driver);
	123	}
	124
	125	void nd_region_exit(void)
	126	{
	127	driver_unregister(&nd_region_driver.drv);
	128	}
	129
	130	MODULE_ALIAS_ND_DEVICE(ND_DEVICE_REGION_PMEM);
	131	MODULE_ALIAS_ND_DEVICE(ND_DEVICE_REGION_BLK);