[GitHub/mt8127/android_kernel_alcatel_ttab.git] / fs / pstore / ram.c

/*
 * RAM Oops/Panic logger
 *
 * Copyright (C) 2010 Marco Stornelli <marco.stornelli@gmail.com>
 * Copyright (C) 2011 Kees Cook <keescook@chromium.org>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * version 2 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.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA
 *
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/kernel.h>
#include <linux/err.h>
#include <linux/module.h>
#include <linux/pstore.h>
#include <linux/time.h>
#include <linux/io.h>
#include <linux/ioport.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/pstore_ram.h>

#define RAMOOPS_KERNMSG_HDR "===="
#define MIN_MEM_SIZE 4096UL

static ulong record_size = MIN_MEM_SIZE;
module_param(record_size, ulong, 0400);
MODULE_PARM_DESC(record_size,
		"size of each dump done on oops/panic");

static ulong mem_address;
module_param(mem_address, ulong, 0400);
MODULE_PARM_DESC(mem_address,
		"start of reserved RAM used to store oops/panic logs");

static ulong mem_size;
module_param(mem_size, ulong, 0400);
MODULE_PARM_DESC(mem_size,
		"size of reserved RAM used to store oops/panic logs");

static int dump_oops = 1;
module_param(dump_oops, int, 0600);
MODULE_PARM_DESC(dump_oops,
		"set to 1 to dump oopses, 0 to only dump panics (default 1)");

static int ramoops_ecc;
module_param_named(ecc, ramoops_ecc, int, 0600);
MODULE_PARM_DESC(ramoops_ecc,
		"set to 1 to enable ECC support");

struct ramoops_context {
	struct persistent_ram_zone **przs;
	phys_addr_t phys_addr;
	unsigned long size;
	size_t record_size;
	int dump_oops;
	bool ecc;
	unsigned int max_dump_cnt;
	unsigned int dump_write_cnt;
	unsigned int dump_read_cnt;
	struct pstore_info pstore;
};

static struct platform_device *dummy;
static struct ramoops_platform_data *dummy_data;

static int ramoops_pstore_open(struct pstore_info *psi)
{
	struct ramoops_context *cxt = psi->data;

	cxt->dump_read_cnt = 0;
	return 0;
}

static struct persistent_ram_zone *
ramoops_get_next_prz(struct persistent_ram_zone *przs[], uint *c, uint max,
		     u64 *id,
		     enum pstore_type_id *typep, enum pstore_type_id type,
		     bool update)
{
	struct persistent_ram_zone *prz;
	int i = (*c)++;

	if (i >= max)
		return NULL;

	prz = przs[i];

	if (update) {
		/* Update old/shadowed buffer. */
		persistent_ram_save_old(prz);
		if (!persistent_ram_old_size(prz))
			return NULL;
	}

	*typep = type;
	*id = i;

	return prz;
}

static ssize_t ramoops_pstore_read(u64 *id, enum pstore_type_id *type,
				   struct timespec *time,
				   char **buf,
				   struct pstore_info *psi)
{
	ssize_t size;
	struct ramoops_context *cxt = psi->data;
	struct persistent_ram_zone *prz;

	prz = ramoops_get_next_prz(cxt->przs, &cxt->dump_read_cnt,
				   cxt->max_dump_cnt, id, type,
				   PSTORE_TYPE_DMESG, 1);
	if (!prz)
		return 0;

	/* TODO(kees): Bogus time for the moment. */
	time->tv_sec = 0;
	time->tv_nsec = 0;

	size = persistent_ram_old_size(prz);
	*buf = kmalloc(size, GFP_KERNEL);
	if (*buf == NULL)
		return -ENOMEM;
	memcpy(*buf, persistent_ram_old(prz), size);

	return size;
}

static size_t ramoops_write_kmsg_hdr(struct persistent_ram_zone *prz)
{
	char *hdr;
	struct timeval timestamp;
	size_t len;

	do_gettimeofday(&timestamp);
	hdr = kasprintf(GFP_ATOMIC, RAMOOPS_KERNMSG_HDR "%lu.%lu\n",
		(long)timestamp.tv_sec, (long)timestamp.tv_usec);
	WARN_ON_ONCE(!hdr);
	len = hdr ? strlen(hdr) : 0;
	persistent_ram_write(prz, hdr, len);
	kfree(hdr);

	return len;
}

static int ramoops_pstore_write(enum pstore_type_id type,
				enum kmsg_dump_reason reason,
				u64 *id,
				unsigned int part,
				size_t size, struct pstore_info *psi)
{
	struct ramoops_context *cxt = psi->data;
	struct persistent_ram_zone *prz = cxt->przs[cxt->dump_write_cnt];
	size_t hlen;

	/* Currently ramoops is designed to only store dmesg dumps. */
	if (type != PSTORE_TYPE_DMESG)
		return -EINVAL;

	/* Out of the various dmesg dump types, ramoops is currently designed
	 * to only store crash logs, rather than storing general kernel logs.
	 */
	if (reason != KMSG_DUMP_OOPS &&
	    reason != KMSG_DUMP_PANIC)
		return -EINVAL;

	/* Skip Oopes when configured to do so. */
	if (reason == KMSG_DUMP_OOPS && !cxt->dump_oops)
		return -EINVAL;

	/* Explicitly only take the first part of any new crash.
	 * If our buffer is larger than kmsg_bytes, this can never happen,
	 * and if our buffer is smaller than kmsg_bytes, we don't want the
	 * report split across multiple records.
	 */
	if (part != 1)
		return -ENOSPC;

	hlen = ramoops_write_kmsg_hdr(prz);
	if (size + hlen > prz->buffer_size)
		size = prz->buffer_size - hlen;
	persistent_ram_write(prz, cxt->pstore.buf, size);

	cxt->dump_write_cnt = (cxt->dump_write_cnt + 1) % cxt->max_dump_cnt;

	return 0;
}

static int ramoops_pstore_erase(enum pstore_type_id type, u64 id,
				struct pstore_info *psi)
{
	struct ramoops_context *cxt = psi->data;

	if (id >= cxt->max_dump_cnt)
		return -EINVAL;

	persistent_ram_free_old(cxt->przs[id]);
	persistent_ram_zap(cxt->przs[id]);

	return 0;
}

static struct ramoops_context oops_cxt = {
	.pstore = {
		.owner	= THIS_MODULE,
		.name	= "ramoops",
		.open	= ramoops_pstore_open,
		.read	= ramoops_pstore_read,
		.write	= ramoops_pstore_write,
		.erase	= ramoops_pstore_erase,
	},
};

static void ramoops_free_przs(struct ramoops_context *cxt)
{
	int i;

	if (!cxt->przs)
		return;

	for (i = 0; cxt->przs[i]; i++)
		persistent_ram_free(cxt->przs[i]);
	kfree(cxt->przs);
}

static int ramoops_init_przs(struct device *dev, struct ramoops_context *cxt,
			      phys_addr_t *paddr, size_t dump_mem_sz)
{
	int err = -ENOMEM;
	int i;

	if (!cxt->record_size)
		return 0;

	cxt->max_dump_cnt = dump_mem_sz / cxt->record_size;
	if (!cxt->max_dump_cnt)
		return -ENOMEM;

	cxt->przs = kzalloc(sizeof(*cxt->przs) * cxt->max_dump_cnt,
			     GFP_KERNEL);
	if (!cxt->przs) {
		dev_err(dev, "failed to initialize a prz array for dumps\n");
		return -ENOMEM;
	}

	for (i = 0; i < cxt->max_dump_cnt; i++) {
		size_t sz = cxt->record_size;

		cxt->przs[i] = persistent_ram_new(*paddr, sz, cxt->ecc);
		if (IS_ERR(cxt->przs[i])) {
			err = PTR_ERR(cxt->przs[i]);
			dev_err(dev, "failed to request mem region (0x%zx@0x%llx): %d\n",
				sz, (unsigned long long)*paddr, err);
			goto fail_prz;
		}
		*paddr += sz;
	}

	return 0;
fail_prz:
	ramoops_free_przs(cxt);
	return err;
}

static int __init ramoops_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct ramoops_platform_data *pdata = pdev->dev.platform_data;
	struct ramoops_context *cxt = &oops_cxt;
	size_t dump_mem_sz;
	phys_addr_t paddr;
	int err = -EINVAL;

	/* Only a single ramoops area allowed at a time, so fail extra
	 * probes.
	 */
	if (cxt->max_dump_cnt)
		goto fail_out;

	if (!pdata->mem_size || !pdata->record_size) {
		pr_err("The memory size and the record size must be "
			"non-zero\n");
		goto fail_out;
	}

	pdata->mem_size = rounddown_pow_of_two(pdata->mem_size);
	pdata->record_size = rounddown_pow_of_two(pdata->record_size);

	cxt->dump_read_cnt = 0;
	cxt->size = pdata->mem_size;
	cxt->phys_addr = pdata->mem_address;
	cxt->record_size = pdata->record_size;
	cxt->dump_oops = pdata->dump_oops;
	cxt->ecc = pdata->ecc;

	paddr = cxt->phys_addr;

	dump_mem_sz = cxt->size;
	err = ramoops_init_przs(dev, cxt, &paddr, dump_mem_sz);
	if (err) {
		pr_err("memory size too small, minimum is %lu\n",
			cxt->record_size);
		goto fail_count;
	}

	cxt->pstore.data = cxt;
	cxt->pstore.bufsize = cxt->przs[0]->buffer_size;
	cxt->pstore.buf = kmalloc(cxt->pstore.bufsize, GFP_KERNEL);
	spin_lock_init(&cxt->pstore.buf_lock);
	if (!cxt->pstore.buf) {
		pr_err("cannot allocate pstore buffer\n");
		goto fail_clear;
	}

	err = pstore_register(&cxt->pstore);
	if (err) {
		pr_err("registering with pstore failed\n");
		goto fail_buf;
	}

	/*
	 * Update the module parameter variables as well so they are visible
	 * through /sys/module/ramoops/parameters/
	 */
	mem_size = pdata->mem_size;
	mem_address = pdata->mem_address;
	record_size = pdata->record_size;
	dump_oops = pdata->dump_oops;

	pr_info("attached 0x%lx@0x%llx (%ux0x%zx), ecc: %s\n",
		cxt->size, (unsigned long long)cxt->phys_addr,
		cxt->max_dump_cnt, cxt->record_size,
		ramoops_ecc ? "on" : "off");

	return 0;

fail_buf:
	kfree(cxt->pstore.buf);
fail_clear:
	cxt->pstore.bufsize = 0;
	cxt->max_dump_cnt = 0;
fail_count:
	ramoops_free_przs(cxt);
fail_out:
	return err;
}

static int __exit ramoops_remove(struct platform_device *pdev)
{
#if 0
	/* TODO(kees): We cannot unload ramoops since pstore doesn't support
	 * unregistering yet.
	 */
	struct ramoops_context *cxt = &oops_cxt;

	iounmap(cxt->virt_addr);
	release_mem_region(cxt->phys_addr, cxt->size);
	cxt->max_dump_cnt = 0;

	/* TODO(kees): When pstore supports unregistering, call it here. */
	kfree(cxt->pstore.buf);
	cxt->pstore.bufsize = 0;

	return 0;
#endif
	return -EBUSY;
}

static struct platform_driver ramoops_driver = {
	.remove		= __exit_p(ramoops_remove),
	.driver		= {
		.name	= "ramoops",
		.owner	= THIS_MODULE,
	},
};

static int __init ramoops_init(void)
{
	int ret;
	ret = platform_driver_probe(&ramoops_driver, ramoops_probe);
	if (ret == -ENODEV) {
		/*
		 * If we didn't find a platform device, we use module parameters
		 * building platform data on the fly.
		 */
		pr_info("platform device not found, using module parameters\n");
		dummy_data = kzalloc(sizeof(struct ramoops_platform_data),
				     GFP_KERNEL);
		if (!dummy_data)
			return -ENOMEM;
		dummy_data->mem_size = mem_size;
		dummy_data->mem_address = mem_address;
		dummy_data->record_size = record_size;
		dummy_data->dump_oops = dump_oops;
		dummy_data->ecc = ramoops_ecc;
		dummy = platform_create_bundle(&ramoops_driver, ramoops_probe,
			NULL, 0, dummy_data,
			sizeof(struct ramoops_platform_data));

		if (IS_ERR(dummy))
			ret = PTR_ERR(dummy);
		else
			ret = 0;
	}

	return ret;
}

static void __exit ramoops_exit(void)
{
	platform_driver_unregister(&ramoops_driver);
	kfree(dummy_data);
}

module_init(ramoops_init);
module_exit(ramoops_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Marco Stornelli <marco.stornelli@gmail.com>");
MODULE_DESCRIPTION("RAM Oops/Panic logger/driver");
Commit	Line	Data
56d611a0 MS	1	/*
	2	* RAM Oops/Panic logger
	3	*
	4	* Copyright (C) 2010 Marco Stornelli <marco.stornelli@gmail.com>
9ba80d99	5	* Copyright (C) 2011 Kees Cook <keescook@chromium.org>
56d611a0 MS	6	*
	7	* This program is free software; you can redistribute it and/or
	8	* modify it under the terms of the GNU General Public License
	9	* version 2 as published by the Free Software Foundation.
	10	*
	11	* This program is distributed in the hope that it will be useful, but
	12	* WITHOUT ANY WARRANTY; without even the implied warranty of
	13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	14	* General Public License for more details.
	15	*
	16	* You should have received a copy of the GNU General Public License
	17	* along with this program; if not, write to the Free Software
	18	* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
	19	* 02110-1301 USA
	20	*
	21	*/
	22
0169256e MS	23	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
0169256e MS	24
56d611a0	25	#include <linux/kernel.h>
83c1b317	26	#include <linux/err.h>
56d611a0	27	#include <linux/module.h>
9ba80d99	28	#include <linux/pstore.h>
56d611a0 MS	29	#include <linux/time.h>
	30	#include <linux/io.h>
	31	#include <linux/ioport.h>
c3b92ce9	32	#include <linux/platform_device.h>
13aefd72	33	#include <linux/slab.h>
1894a253	34	#include <linux/pstore_ram.h>
56d611a0 MS	35
56d611a0 MS	36	#define RAMOOPS_KERNMSG_HDR "===="
3e5c4fad	37	#define MIN_MEM_SIZE 4096UL
56d611a0	38
3e5c4fad SI	39	static ulong record_size = MIN_MEM_SIZE;
	40	module_param(record_size, ulong, 0400);
	41	MODULE_PARM_DESC(record_size,
	42	"size of each dump done on oops/panic");
56d611a0 MS	43
	44	static ulong mem_address;
	45	module_param(mem_address, ulong, 0400);
	46	MODULE_PARM_DESC(mem_address,
	47	"start of reserved RAM used to store oops/panic logs");
	48
	49	static ulong mem_size;
	50	module_param(mem_size, ulong, 0400);
	51	MODULE_PARM_DESC(mem_size,
	52	"size of reserved RAM used to store oops/panic logs");
	53
	54	static int dump_oops = 1;
	55	module_param(dump_oops, int, 0600);
	56	MODULE_PARM_DESC(dump_oops,
	57	"set to 1 to dump oopses, 0 to only dump panics (default 1)");
	58
39eb7e97 AV	59	static int ramoops_ecc;
	60	module_param_named(ecc, ramoops_ecc, int, 0600);
	61	MODULE_PARM_DESC(ramoops_ecc,
	62	"set to 1 to enable ECC support");
	63
9ba80d99	64	struct ramoops_context {
896fc1f0	65	struct persistent_ram_zone **przs;
56d611a0 MS	66	phys_addr_t phys_addr;
56d611a0 MS	67	unsigned long size;
9ba80d99	68	size_t record_size;
6b4d2a27	69	int dump_oops;
39eb7e97	70	bool ecc;
cac2eb7b AV	71	unsigned int max_dump_cnt;
	72	unsigned int dump_write_cnt;
	73	unsigned int dump_read_cnt;
9ba80d99 KC	74	struct pstore_info pstore;
9ba80d99 KC	75	};
56d611a0	76
13aefd72 MS	77	static struct platform_device *dummy;
	78	static struct ramoops_platform_data *dummy_data;
	79
9ba80d99 KC	80	static int ramoops_pstore_open(struct pstore_info *psi)
	81	{
	82	struct ramoops_context *cxt = psi->data;
	83
cac2eb7b	84	cxt->dump_read_cnt = 0;
9ba80d99 KC	85	return 0;
	86	}
	87
755d66b4 AV	88	static struct persistent_ram_zone *
	89	ramoops_get_next_prz(struct persistent_ram_zone przs[], uint c, uint max,
	90	u64 *id,
	91	enum pstore_type_id *typep, enum pstore_type_id type,
	92	bool update)
	93	{
	94	struct persistent_ram_zone *prz;
	95	int i = (*c)++;
	96
	97	if (i >= max)
	98	return NULL;
	99
	100	prz = przs[i];
	101
	102	if (update) {
	103	/* Update old/shadowed buffer. */
	104	persistent_ram_save_old(prz);
	105	if (!persistent_ram_old_size(prz))
	106	return NULL;
	107	}
	108
	109	*typep = type;
	110	*id = i;
	111
	112	return prz;
	113	}
	114
9ba80d99 KC	115	static ssize_t ramoops_pstore_read(u64 id, enum pstore_type_id type,
	116	struct timespec *time,
	117	char **buf,
	118	struct pstore_info *psi)
56d611a0	119	{
9ba80d99	120	ssize_t size;
9ba80d99	121	struct ramoops_context *cxt = psi->data;
896fc1f0	122	struct persistent_ram_zone *prz;
9ba80d99	123
755d66b4 AV	124	prz = ramoops_get_next_prz(cxt->przs, &cxt->dump_read_cnt,
	125	cxt->max_dump_cnt, id, type,
	126	PSTORE_TYPE_DMESG, 1);
	127	if (!prz)
	128	return 0;
896fc1f0	129
9ba80d99 KC	130	/* TODO(kees): Bogus time for the moment. */
	131	time->tv_sec = 0;
	132	time->tv_nsec = 0;
	133
896fc1f0	134	size = persistent_ram_old_size(prz);
9ba80d99 KC	135	*buf = kmalloc(size, GFP_KERNEL);
	136	if (*buf == NULL)
	137	return -ENOMEM;
896fc1f0	138	memcpy(*buf, persistent_ram_old(prz), size);
9ba80d99 KC	139
	140	return size;
	141	}
	142
896fc1f0 AV	143	static size_t ramoops_write_kmsg_hdr(struct persistent_ram_zone *prz)
	144	{
	145	char *hdr;
	146	struct timeval timestamp;
	147	size_t len;
	148
	149	do_gettimeofday(&timestamp);
	150	hdr = kasprintf(GFP_ATOMIC, RAMOOPS_KERNMSG_HDR "%lu.%lu\n",
	151	(long)timestamp.tv_sec, (long)timestamp.tv_usec);
	152	WARN_ON_ONCE(!hdr);
	153	len = hdr ? strlen(hdr) : 0;
	154	persistent_ram_write(prz, hdr, len);
	155	kfree(hdr);
	156
	157	return len;
	158	}
	159
9ba80d99 KC	160	static int ramoops_pstore_write(enum pstore_type_id type,
	161	enum kmsg_dump_reason reason,
	162	u64 *id,
	163	unsigned int part,
	164	size_t size, struct pstore_info *psi)
	165	{
9ba80d99	166	struct ramoops_context *cxt = psi->data;
cac2eb7b	167	struct persistent_ram_zone *prz = cxt->przs[cxt->dump_write_cnt];
896fc1f0	168	size_t hlen;
9ba80d99 KC	169
	170	/* Currently ramoops is designed to only store dmesg dumps. */
	171	if (type != PSTORE_TYPE_DMESG)
	172	return -EINVAL;
56d611a0	173
9ba80d99 KC	174	/* Out of the various dmesg dump types, ramoops is currently designed
	175	* to only store crash logs, rather than storing general kernel logs.
	176	*/
fc2d557c	177	if (reason != KMSG_DUMP_OOPS &&
a3dd3323	178	reason != KMSG_DUMP_PANIC)
9ba80d99	179	return -EINVAL;
fc2d557c	180
9ba80d99	181	/* Skip Oopes when configured to do so. */
6b4d2a27	182	if (reason == KMSG_DUMP_OOPS && !cxt->dump_oops)
9ba80d99 KC	183	return -EINVAL;
	184
	185	/* Explicitly only take the first part of any new crash.
	186	* If our buffer is larger than kmsg_bytes, this can never happen,
	187	* and if our buffer is smaller than kmsg_bytes, we don't want the
	188	* report split across multiple records.
	189	*/
	190	if (part != 1)
	191	return -ENOSPC;
56d611a0	192
896fc1f0 AV	193	hlen = ramoops_write_kmsg_hdr(prz);
	194	if (size + hlen > prz->buffer_size)
	195	size = prz->buffer_size - hlen;
	196	persistent_ram_write(prz, cxt->pstore.buf, size);
56d611a0	197
cac2eb7b	198	cxt->dump_write_cnt = (cxt->dump_write_cnt + 1) % cxt->max_dump_cnt;
9ba80d99 KC	199
	200	return 0;
	201	}
	202
	203	static int ramoops_pstore_erase(enum pstore_type_id type, u64 id,
	204	struct pstore_info *psi)
	205	{
9ba80d99 KC	206	struct ramoops_context *cxt = psi->data;
9ba80d99 KC	207
cac2eb7b	208	if (id >= cxt->max_dump_cnt)
9ba80d99 KC	209	return -EINVAL;
9ba80d99 KC	210
896fc1f0	211	persistent_ram_free_old(cxt->przs[id]);
93cce049	212	persistent_ram_zap(cxt->przs[id]);
9ba80d99 KC	213
9ba80d99 KC	214	return 0;
56d611a0 MS	215	}
56d611a0 MS	216
9ba80d99 KC	217	static struct ramoops_context oops_cxt = {
	218	.pstore = {
	219	.owner = THIS_MODULE,
	220	.name = "ramoops",
	221	.open = ramoops_pstore_open,
	222	.read = ramoops_pstore_read,
	223	.write = ramoops_pstore_write,
	224	.erase = ramoops_pstore_erase,
	225	},
	226	};
	227
f4c5d242 AV	228	static void ramoops_free_przs(struct ramoops_context *cxt)
	229	{
	230	int i;
	231
	232	if (!cxt->przs)
	233	return;
	234
	235	for (i = 0; cxt->przs[i]; i++)
	236	persistent_ram_free(cxt->przs[i]);
	237	kfree(cxt->przs);
	238	}
	239
	240	static int ramoops_init_przs(struct device dev, struct ramoops_context cxt,
	241	phys_addr_t *paddr, size_t dump_mem_sz)
	242	{
	243	int err = -ENOMEM;
	244	int i;
	245
	246	if (!cxt->record_size)
	247	return 0;
	248
	249	cxt->max_dump_cnt = dump_mem_sz / cxt->record_size;
	250	if (!cxt->max_dump_cnt)
	251	return -ENOMEM;
	252
	253	cxt->przs = kzalloc(sizeof(cxt->przs) cxt->max_dump_cnt,
	254	GFP_KERNEL);
	255	if (!cxt->przs) {
	256	dev_err(dev, "failed to initialize a prz array for dumps\n");
	257	return -ENOMEM;
	258	}
	259
	260	for (i = 0; i < cxt->max_dump_cnt; i++) {
	261	size_t sz = cxt->record_size;
	262
	263	cxt->przs[i] = persistent_ram_new(*paddr, sz, cxt->ecc);
	264	if (IS_ERR(cxt->przs[i])) {
	265	err = PTR_ERR(cxt->przs[i]);
	266	dev_err(dev, "failed to request mem region (0x%zx@0x%llx): %d\n",
	267	sz, (unsigned long long)*paddr, err);
	268	goto fail_prz;
	269	}
	270	*paddr += sz;
	271	}
	272
	273	return 0;
	274	fail_prz:
	275	ramoops_free_przs(cxt);
	276	return err;
	277	}
	278
c3b92ce9	279	static int __init ramoops_probe(struct platform_device *pdev)
56d611a0	280	{
896fc1f0	281	struct device *dev = &pdev->dev;
c3b92ce9	282	struct ramoops_platform_data *pdata = pdev->dev.platform_data;
56d611a0	283	struct ramoops_context *cxt = &oops_cxt;
f4c5d242 AV	284	size_t dump_mem_sz;
f4c5d242 AV	285	phys_addr_t paddr;
56d611a0 MS	286	int err = -EINVAL;
56d611a0 MS	287
9ba80d99 KC	288	/* Only a single ramoops area allowed at a time, so fail extra
	289	* probes.
	290	*/
cac2eb7b	291	if (cxt->max_dump_cnt)
9ba80d99 KC	292	goto fail_out;
9ba80d99 KC	293
3e5c4fad SI	294	if (!pdata->mem_size \|\| !pdata->record_size) {
	295	pr_err("The memory size and the record size must be "
	296	"non-zero\n");
9ba80d99	297	goto fail_out;
56d611a0 MS	298	}
56d611a0 MS	299
fdb59507 MS	300	pdata->mem_size = rounddown_pow_of_two(pdata->mem_size);
fdb59507 MS	301	pdata->record_size = rounddown_pow_of_two(pdata->record_size);
56d611a0	302
cac2eb7b	303	cxt->dump_read_cnt = 0;
13aefd72 MS	304	cxt->size = pdata->mem_size;
13aefd72 MS	305	cxt->phys_addr = pdata->mem_address;
3e5c4fad	306	cxt->record_size = pdata->record_size;
6b4d2a27	307	cxt->dump_oops = pdata->dump_oops;
39eb7e97	308	cxt->ecc = pdata->ecc;
56d611a0	309
f4c5d242	310	paddr = cxt->phys_addr;
896fc1f0	311
f4c5d242 AV	312	dump_mem_sz = cxt->size;
	313	err = ramoops_init_przs(dev, cxt, &paddr, dump_mem_sz);
	314	if (err) {
	315	pr_err("memory size too small, minimum is %lu\n",
	316	cxt->record_size);
	317	goto fail_count;
896fc1f0 AV	318	}
896fc1f0 AV	319
9ba80d99	320	cxt->pstore.data = cxt;
896fc1f0	321	cxt->pstore.bufsize = cxt->przs[0]->buffer_size;
9ba80d99 KC	322	cxt->pstore.buf = kmalloc(cxt->pstore.bufsize, GFP_KERNEL);
	323	spin_lock_init(&cxt->pstore.buf_lock);
	324	if (!cxt->pstore.buf) {
	325	pr_err("cannot allocate pstore buffer\n");
	326	goto fail_clear;
	327	}
	328
9ba80d99	329	err = pstore_register(&cxt->pstore);
56d611a0	330	if (err) {
9ba80d99	331	pr_err("registering with pstore failed\n");
896fc1f0	332	goto fail_buf;
56d611a0 MS	333	}
56d611a0 MS	334
c755201e KC	335	/*
	336	* Update the module parameter variables as well so they are visible
	337	* through /sys/module/ramoops/parameters/
	338	*/
	339	mem_size = pdata->mem_size;
	340	mem_address = pdata->mem_address;
	341	record_size = pdata->record_size;
	342	dump_oops = pdata->dump_oops;
	343
39eb7e97	344	pr_info("attached 0x%lx@0x%llx (%ux0x%zx), ecc: %s\n",
d109a674	345	cxt->size, (unsigned long long)cxt->phys_addr,
cac2eb7b	346	cxt->max_dump_cnt, cxt->record_size,
39eb7e97	347	ramoops_ecc ? "on" : "off");
9ba80d99	348
56d611a0 MS	349	return 0;
56d611a0 MS	350
9ba80d99 KC	351	fail_buf:
	352	kfree(cxt->pstore.buf);
	353	fail_clear:
	354	cxt->pstore.bufsize = 0;
cac2eb7b	355	cxt->max_dump_cnt = 0;
f4c5d242 AV	356	fail_count:
f4c5d242 AV	357	ramoops_free_przs(cxt);
9ba80d99	358	fail_out:
56d611a0 MS	359	return err;
	360	}
	361
c3b92ce9	362	static int __exit ramoops_remove(struct platform_device *pdev)
56d611a0	363	{
9ba80d99 KC	364	#if 0
	365	/* TODO(kees): We cannot unload ramoops since pstore doesn't support
	366	* unregistering yet.
	367	*/
56d611a0 MS	368	struct ramoops_context *cxt = &oops_cxt;
56d611a0 MS	369
56d611a0 MS	370	iounmap(cxt->virt_addr);
56d611a0 MS	371	release_mem_region(cxt->phys_addr, cxt->size);
cac2eb7b	372	cxt->max_dump_cnt = 0;
9ba80d99 KC	373
	374	/* TODO(kees): When pstore supports unregistering, call it here. */
	375	kfree(cxt->pstore.buf);
	376	cxt->pstore.bufsize = 0;
	377
c3b92ce9	378	return 0;
9ba80d99 KC	379	#endif
9ba80d99 KC	380	return -EBUSY;
56d611a0 MS	381	}
56d611a0 MS	382
c3b92ce9 KP	383	static struct platform_driver ramoops_driver = {
	384	.remove = __exit_p(ramoops_remove),
	385	.driver = {
	386	.name = "ramoops",
	387	.owner = THIS_MODULE,
	388	},
	389	};
	390
	391	static int __init ramoops_init(void)
	392	{
13aefd72 MS	393	int ret;
	394	ret = platform_driver_probe(&ramoops_driver, ramoops_probe);
	395	if (ret == -ENODEV) {
	396	/*
	397	* If we didn't find a platform device, we use module parameters
	398	* building platform data on the fly.
	399	*/
0169256e	400	pr_info("platform device not found, using module parameters\n");
13aefd72 MS	401	dummy_data = kzalloc(sizeof(struct ramoops_platform_data),
	402	GFP_KERNEL);
	403	if (!dummy_data)
	404	return -ENOMEM;
	405	dummy_data->mem_size = mem_size;
	406	dummy_data->mem_address = mem_address;
3e5c4fad	407	dummy_data->record_size = record_size;
6b4d2a27	408	dummy_data->dump_oops = dump_oops;
39eb7e97	409	dummy_data->ecc = ramoops_ecc;
13aefd72 MS	410	dummy = platform_create_bundle(&ramoops_driver, ramoops_probe,
	411	NULL, 0, dummy_data,
	412	sizeof(struct ramoops_platform_data));
	413
	414	if (IS_ERR(dummy))
	415	ret = PTR_ERR(dummy);
	416	else
	417	ret = 0;
	418	}
	419
	420	return ret;
c3b92ce9 KP	421	}
	422
	423	static void __exit ramoops_exit(void)
	424	{
	425	platform_driver_unregister(&ramoops_driver);
13aefd72	426	kfree(dummy_data);
c3b92ce9	427	}
56d611a0 MS	428
	429	module_init(ramoops_init);
	430	module_exit(ramoops_exit);
	431
	432	MODULE_LICENSE("GPL");
	433	MODULE_AUTHOR("Marco Stornelli <marco.stornelli@gmail.com>");
	434	MODULE_DESCRIPTION("RAM Oops/Panic logger/driver");