[deliverable/linux.git] / arch / x86 / kernel / cpu / mtrr / if.c

#include <linux/capability.h>
#include <linux/seq_file.h>
#include <linux/uaccess.h>
#include <linux/proc_fs.h>
#include <linux/module.h>
#include <linux/ctype.h>
#include <linux/string.h>
#include <linux/slab.h>
#include <linux/init.h>

#define LINE_SIZE 80

#include <asm/mtrr.h>

#include "mtrr.h"

#define FILE_FCOUNT(f) (((struct seq_file *)((f)->private_data))->private)

static const char *const mtrr_strings[MTRR_NUM_TYPES] =
{
	"uncachable",		/* 0 */
	"write-combining",	/* 1 */
	"?",			/* 2 */
	"?",			/* 3 */
	"write-through",	/* 4 */
	"write-protect",	/* 5 */
	"write-back",		/* 6 */
};

const char *mtrr_attrib_to_str(int x)
{
	return (x <= 6) ? mtrr_strings[x] : "?";
}

#ifdef CONFIG_PROC_FS

static int
mtrr_file_add(unsigned long base, unsigned long size,
	      unsigned int type, bool increment, struct file *file, int page)
{
	unsigned int *fcount = FILE_FCOUNT(file);
	int reg, max;

	max = num_var_ranges;
	if (fcount == NULL) {
		fcount = kzalloc(max * sizeof *fcount, GFP_KERNEL);
		if (!fcount)
			return -ENOMEM;
		FILE_FCOUNT(file) = fcount;
	}
	if (!page) {
		if ((base & (PAGE_SIZE - 1)) || (size & (PAGE_SIZE - 1)))
			return -EINVAL;
		base >>= PAGE_SHIFT;
		size >>= PAGE_SHIFT;
	}
	reg = mtrr_add_page(base, size, type, true);
	if (reg >= 0)
		++fcount[reg];
	return reg;
}

static int
mtrr_file_del(unsigned long base, unsigned long size,
	      struct file *file, int page)
{
	unsigned int *fcount = FILE_FCOUNT(file);
	int reg;

	if (!page) {
		if ((base & (PAGE_SIZE - 1)) || (size & (PAGE_SIZE - 1)))
			return -EINVAL;
		base >>= PAGE_SHIFT;
		size >>= PAGE_SHIFT;
	}
	reg = mtrr_del_page(-1, base, size);
	if (reg < 0)
		return reg;
	if (fcount == NULL)
		return reg;
	if (fcount[reg] < 1)
		return -EINVAL;
	--fcount[reg];
	return reg;
}

/*
 * seq_file can seek but we ignore it.
 *
 * Format of control line:
 *    "base=%Lx size=%Lx type=%s" or "disable=%d"
 */
static ssize_t
mtrr_write(struct file *file, const char __user *buf, size_t len, loff_t * ppos)
{
	int i, err;
	unsigned long reg;
	unsigned long long base, size;
	char *ptr;
	char line[LINE_SIZE];
	int length;
	size_t linelen;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

	memset(line, 0, LINE_SIZE);

	length = len;
	length--;

	if (length > LINE_SIZE - 1)
		length = LINE_SIZE - 1;

	if (length < 0)
		return -EINVAL;

	if (copy_from_user(line, buf, length))
		return -EFAULT;

	linelen = strlen(line);
	ptr = line + linelen - 1;
	if (linelen && *ptr == '\n')
		*ptr = '\0';

	if (!strncmp(line, "disable=", 8)) {
		reg = simple_strtoul(line + 8, &ptr, 0);
		err = mtrr_del_page(reg, 0, 0);
		if (err < 0)
			return err;
		return len;
	}

	if (strncmp(line, "base=", 5))
		return -EINVAL;

	base = simple_strtoull(line + 5, &ptr, 0);
	ptr = skip_spaces(ptr);

	if (strncmp(ptr, "size=", 5))
		return -EINVAL;

	size = simple_strtoull(ptr + 5, &ptr, 0);
	if ((base & 0xfff) || (size & 0xfff))
		return -EINVAL;
	ptr = skip_spaces(ptr);

	if (strncmp(ptr, "type=", 5))
		return -EINVAL;
	ptr = skip_spaces(ptr + 5);

	for (i = 0; i < MTRR_NUM_TYPES; ++i) {
		if (strcmp(ptr, mtrr_strings[i]))
			continue;
		base >>= PAGE_SHIFT;
		size >>= PAGE_SHIFT;
		err = mtrr_add_page((unsigned long)base, (unsigned long)size, i, true);
		if (err < 0)
			return err;
		return len;
	}
	return -EINVAL;
}

static long
mtrr_ioctl(struct file *file, unsigned int cmd, unsigned long __arg)
{
	int err = 0;
	mtrr_type type;
	unsigned long base;
	unsigned long size;
	struct mtrr_sentry sentry;
	struct mtrr_gentry gentry;
	void __user *arg = (void __user *) __arg;

	switch (cmd) {
	case MTRRIOC_ADD_ENTRY:
	case MTRRIOC_SET_ENTRY:
	case MTRRIOC_DEL_ENTRY:
	case MTRRIOC_KILL_ENTRY:
	case MTRRIOC_ADD_PAGE_ENTRY:
	case MTRRIOC_SET_PAGE_ENTRY:
	case MTRRIOC_DEL_PAGE_ENTRY:
	case MTRRIOC_KILL_PAGE_ENTRY:
		if (copy_from_user(&sentry, arg, sizeof sentry))
			return -EFAULT;
		break;
	case MTRRIOC_GET_ENTRY:
	case MTRRIOC_GET_PAGE_ENTRY:
		if (copy_from_user(&gentry, arg, sizeof gentry))
			return -EFAULT;
		break;
#ifdef CONFIG_COMPAT
	case MTRRIOC32_ADD_ENTRY:
	case MTRRIOC32_SET_ENTRY:
	case MTRRIOC32_DEL_ENTRY:
	case MTRRIOC32_KILL_ENTRY:
	case MTRRIOC32_ADD_PAGE_ENTRY:
	case MTRRIOC32_SET_PAGE_ENTRY:
	case MTRRIOC32_DEL_PAGE_ENTRY:
	case MTRRIOC32_KILL_PAGE_ENTRY: {
		struct mtrr_sentry32 __user *s32;

		s32 = (struct mtrr_sentry32 __user *)__arg;
		err = get_user(sentry.base, &s32->base);
		err |= get_user(sentry.size, &s32->size);
		err |= get_user(sentry.type, &s32->type);
		if (err)
			return err;
		break;
	}
	case MTRRIOC32_GET_ENTRY:
	case MTRRIOC32_GET_PAGE_ENTRY: {
		struct mtrr_gentry32 __user *g32;

		g32 = (struct mtrr_gentry32 __user *)__arg;
		err = get_user(gentry.regnum, &g32->regnum);
		err |= get_user(gentry.base, &g32->base);
		err |= get_user(gentry.size, &g32->size);
		err |= get_user(gentry.type, &g32->type);
		if (err)
			return err;
		break;
	}
#endif
	}

	switch (cmd) {
	default:
		return -ENOTTY;
	case MTRRIOC_ADD_ENTRY:
#ifdef CONFIG_COMPAT
	case MTRRIOC32_ADD_ENTRY:
#endif
		if (!capable(CAP_SYS_ADMIN))
			return -EPERM;
		err =
		    mtrr_file_add(sentry.base, sentry.size, sentry.type, true,
				  file, 0);
		break;
	case MTRRIOC_SET_ENTRY:
#ifdef CONFIG_COMPAT
	case MTRRIOC32_SET_ENTRY:
#endif
		if (!capable(CAP_SYS_ADMIN))
			return -EPERM;
		err = mtrr_add(sentry.base, sentry.size, sentry.type, false);
		break;
	case MTRRIOC_DEL_ENTRY:
#ifdef CONFIG_COMPAT
	case MTRRIOC32_DEL_ENTRY:
#endif
		if (!capable(CAP_SYS_ADMIN))
			return -EPERM;
		err = mtrr_file_del(sentry.base, sentry.size, file, 0);
		break;
	case MTRRIOC_KILL_ENTRY:
#ifdef CONFIG_COMPAT
	case MTRRIOC32_KILL_ENTRY:
#endif
		if (!capable(CAP_SYS_ADMIN))
			return -EPERM;
		err = mtrr_del(-1, sentry.base, sentry.size);
		break;
	case MTRRIOC_GET_ENTRY:
#ifdef CONFIG_COMPAT
	case MTRRIOC32_GET_ENTRY:
#endif
		if (gentry.regnum >= num_var_ranges)
			return -EINVAL;
		mtrr_if->get(gentry.regnum, &base, &size, &type);

		/* Hide entries that go above 4GB */
		if (base + size - 1 >= (1UL << (8 * sizeof(gentry.size) - PAGE_SHIFT))
		    || size >= (1UL << (8 * sizeof(gentry.size) - PAGE_SHIFT)))
			gentry.base = gentry.size = gentry.type = 0;
		else {
			gentry.base = base << PAGE_SHIFT;
			gentry.size = size << PAGE_SHIFT;
			gentry.type = type;
		}

		break;
	case MTRRIOC_ADD_PAGE_ENTRY:
#ifdef CONFIG_COMPAT
	case MTRRIOC32_ADD_PAGE_ENTRY:
#endif
		if (!capable(CAP_SYS_ADMIN))
			return -EPERM;
		err =
		    mtrr_file_add(sentry.base, sentry.size, sentry.type, true,
				  file, 1);
		break;
	case MTRRIOC_SET_PAGE_ENTRY:
#ifdef CONFIG_COMPAT
	case MTRRIOC32_SET_PAGE_ENTRY:
#endif
		if (!capable(CAP_SYS_ADMIN))
			return -EPERM;
		err =
		    mtrr_add_page(sentry.base, sentry.size, sentry.type, false);
		break;
	case MTRRIOC_DEL_PAGE_ENTRY:
#ifdef CONFIG_COMPAT
	case MTRRIOC32_DEL_PAGE_ENTRY:
#endif
		if (!capable(CAP_SYS_ADMIN))
			return -EPERM;
		err = mtrr_file_del(sentry.base, sentry.size, file, 1);
		break;
	case MTRRIOC_KILL_PAGE_ENTRY:
#ifdef CONFIG_COMPAT
	case MTRRIOC32_KILL_PAGE_ENTRY:
#endif
		if (!capable(CAP_SYS_ADMIN))
			return -EPERM;
		err = mtrr_del_page(-1, sentry.base, sentry.size);
		break;
	case MTRRIOC_GET_PAGE_ENTRY:
#ifdef CONFIG_COMPAT
	case MTRRIOC32_GET_PAGE_ENTRY:
#endif
		if (gentry.regnum >= num_var_ranges)
			return -EINVAL;
		mtrr_if->get(gentry.regnum, &base, &size, &type);
		/* Hide entries that would overflow */
		if (size != (__typeof__(gentry.size))size)
			gentry.base = gentry.size = gentry.type = 0;
		else {
			gentry.base = base;
			gentry.size = size;
			gentry.type = type;
		}
		break;
	}

	if (err)
		return err;

	switch (cmd) {
	case MTRRIOC_GET_ENTRY:
	case MTRRIOC_GET_PAGE_ENTRY:
		if (copy_to_user(arg, &gentry, sizeof gentry))
			err = -EFAULT;
		break;
#ifdef CONFIG_COMPAT
	case MTRRIOC32_GET_ENTRY:
	case MTRRIOC32_GET_PAGE_ENTRY: {
		struct mtrr_gentry32 __user *g32;

		g32 = (struct mtrr_gentry32 __user *)__arg;
		err = put_user(gentry.base, &g32->base);
		err |= put_user(gentry.size, &g32->size);
		err |= put_user(gentry.regnum, &g32->regnum);
		err |= put_user(gentry.type, &g32->type);
		break;
	}
#endif
	}
	return err;
}

static int mtrr_close(struct inode *ino, struct file *file)
{
	unsigned int *fcount = FILE_FCOUNT(file);
	int i, max;

	if (fcount != NULL) {
		max = num_var_ranges;
		for (i = 0; i < max; ++i) {
			while (fcount[i] > 0) {
				mtrr_del(i, 0, 0);
				--fcount[i];
			}
		}
		kfree(fcount);
		FILE_FCOUNT(file) = NULL;
	}
	return single_release(ino, file);
}

static int mtrr_seq_show(struct seq_file *seq, void *offset);

static int mtrr_open(struct inode *inode, struct file *file)
{
	if (!mtrr_if)
		return -EIO;
	if (!mtrr_if->get)
		return -ENXIO;
	return single_open(file, mtrr_seq_show, NULL);
}

static const struct file_operations mtrr_fops = {
	.owner			= THIS_MODULE,
	.open			= mtrr_open,
	.read			= seq_read,
	.llseek			= seq_lseek,
	.write			= mtrr_write,
	.unlocked_ioctl		= mtrr_ioctl,
	.compat_ioctl		= mtrr_ioctl,
	.release		= mtrr_close,
};

static int mtrr_seq_show(struct seq_file *seq, void *offset)
{
	char factor;
	int i, max, len;
	mtrr_type type;
	unsigned long base, size;

	len = 0;
	max = num_var_ranges;
	for (i = 0; i < max; i++) {
		mtrr_if->get(i, &base, &size, &type);
		if (size == 0) {
			mtrr_usage_table[i] = 0;
			continue;
		}
		if (size < (0x100000 >> PAGE_SHIFT)) {
			/* less than 1MB */
			factor = 'K';
			size <<= PAGE_SHIFT - 10;
		} else {
			factor = 'M';
			size >>= 20 - PAGE_SHIFT;
		}
		/* Base can be > 32bit */
		len += seq_printf(seq, "reg%02i: base=0x%06lx000 "
			"(%5luMB), size=%5lu%cB, count=%d: %s\n",
			i, base, base >> (20 - PAGE_SHIFT), size,
			factor, mtrr_usage_table[i],
			mtrr_attrib_to_str(type));
	}
	return 0;
}

static int __init mtrr_if_init(void)
{
	struct cpuinfo_x86 *c = &boot_cpu_data;

	if ((!cpu_has(c, X86_FEATURE_MTRR)) &&
	    (!cpu_has(c, X86_FEATURE_K6_MTRR)) &&
	    (!cpu_has(c, X86_FEATURE_CYRIX_ARR)) &&
	    (!cpu_has(c, X86_FEATURE_CENTAUR_MCR)))
		return -ENODEV;

	proc_create("mtrr", S_IWUSR | S_IRUGO, NULL, &mtrr_fops);
	return 0;
}
arch_initcall(mtrr_if_init);
#endif			/*  CONFIG_PROC_FS  */
Commit	Line	Data
	1	#include <linux/capability.h>
	2	#include <linux/seq_file.h>
	3	#include <linux/uaccess.h>
	4	#include <linux/proc_fs.h>
	5	#include <linux/module.h>
	6	#include <linux/ctype.h>
	7	#include <linux/string.h>
	8	#include <linux/slab.h>
	9	#include <linux/init.h>
	10
	11	#define LINE_SIZE 80
	12
	13	#include <asm/mtrr.h>
	14
	15	#include "mtrr.h"
	16
	17	#define FILE_FCOUNT(f) (((struct seq_file *)((f)->private_data))->private)
	18
	19	static const char *const mtrr_strings[MTRR_NUM_TYPES] =
	20	{
	21	"uncachable", /* 0 */
	22	"write-combining", /* 1 */
	23	"?", /* 2 */
	24	"?", /* 3 */
	25	"write-through", /* 4 */
	26	"write-protect", /* 5 */
	27	"write-back", /* 6 */
	28	};
	29
	30	const char *mtrr_attrib_to_str(int x)
	31	{
	32	return (x <= 6) ? mtrr_strings[x] : "?";
	33	}
	34
	35	#ifdef CONFIG_PROC_FS
	36
	37	static int
	38	mtrr_file_add(unsigned long base, unsigned long size,
	39	unsigned int type, bool increment, struct file *file, int page)
	40	{
	41	unsigned int *fcount = FILE_FCOUNT(file);
	42	int reg, max;
	43
	44	max = num_var_ranges;
	45	if (fcount == NULL) {
	46	fcount = kzalloc(max * sizeof *fcount, GFP_KERNEL);
	47	if (!fcount)
	48	return -ENOMEM;
	49	FILE_FCOUNT(file) = fcount;
	50	}
	51	if (!page) {
	52	if ((base & (PAGE_SIZE - 1)) \|\| (size & (PAGE_SIZE - 1)))
	53	return -EINVAL;
	54	base >>= PAGE_SHIFT;
	55	size >>= PAGE_SHIFT;
	56	}
	57	reg = mtrr_add_page(base, size, type, true);
	58	if (reg >= 0)
	59	++fcount[reg];
	60	return reg;
	61	}
	62
	63	static int
	64	mtrr_file_del(unsigned long base, unsigned long size,
	65	struct file *file, int page)
	66	{
	67	unsigned int *fcount = FILE_FCOUNT(file);
	68	int reg;
	69
	70	if (!page) {
	71	if ((base & (PAGE_SIZE - 1)) \|\| (size & (PAGE_SIZE - 1)))
	72	return -EINVAL;
	73	base >>= PAGE_SHIFT;
	74	size >>= PAGE_SHIFT;
	75	}
	76	reg = mtrr_del_page(-1, base, size);
	77	if (reg < 0)
	78	return reg;
	79	if (fcount == NULL)
	80	return reg;
	81	if (fcount[reg] < 1)
	82	return -EINVAL;
	83	--fcount[reg];
	84	return reg;
	85	}
	86
	87	/*
	88	* seq_file can seek but we ignore it.
	89	*
	90	* Format of control line:
	91	* "base=%Lx size=%Lx type=%s" or "disable=%d"
	92	*/
	93	static ssize_t
	94	mtrr_write(struct file file, const char __user buf, size_t len, loff_t * ppos)
	95	{
	96	int i, err;
	97	unsigned long reg;
	98	unsigned long long base, size;
	99	char *ptr;
	100	char line[LINE_SIZE];
	101	int length;
	102	size_t linelen;
	103
	104	if (!capable(CAP_SYS_ADMIN))
	105	return -EPERM;
	106
	107	memset(line, 0, LINE_SIZE);
	108
	109	length = len;
	110	length--;
	111
	112	if (length > LINE_SIZE - 1)
	113	length = LINE_SIZE - 1;
	114
	115	if (length < 0)
	116	return -EINVAL;
	117
	118	if (copy_from_user(line, buf, length))
	119	return -EFAULT;
	120
	121	linelen = strlen(line);
	122	ptr = line + linelen - 1;
	123	if (linelen && *ptr == '\n')
	124	*ptr = '\0';
	125
	126	if (!strncmp(line, "disable=", 8)) {
	127	reg = simple_strtoul(line + 8, &ptr, 0);
	128	err = mtrr_del_page(reg, 0, 0);
	129	if (err < 0)
	130	return err;
	131	return len;
	132	}
	133
	134	if (strncmp(line, "base=", 5))
	135	return -EINVAL;
	136
	137	base = simple_strtoull(line + 5, &ptr, 0);
	138	ptr = skip_spaces(ptr);
	139
	140	if (strncmp(ptr, "size=", 5))
	141	return -EINVAL;
	142
	143	size = simple_strtoull(ptr + 5, &ptr, 0);
	144	if ((base & 0xfff) \|\| (size & 0xfff))
	145	return -EINVAL;
	146	ptr = skip_spaces(ptr);
	147
	148	if (strncmp(ptr, "type=", 5))
	149	return -EINVAL;
	150	ptr = skip_spaces(ptr + 5);
	151
	152	for (i = 0; i < MTRR_NUM_TYPES; ++i) {
	153	if (strcmp(ptr, mtrr_strings[i]))
	154	continue;
	155	base >>= PAGE_SHIFT;
	156	size >>= PAGE_SHIFT;
	157	err = mtrr_add_page((unsigned long)base, (unsigned long)size, i, true);
	158	if (err < 0)
	159	return err;
	160	return len;
	161	}
	162	return -EINVAL;
	163	}
	164
	165	static long
	166	mtrr_ioctl(struct file *file, unsigned int cmd, unsigned long __arg)
	167	{
	168	int err = 0;
	169	mtrr_type type;
	170	unsigned long base;
	171	unsigned long size;
	172	struct mtrr_sentry sentry;
	173	struct mtrr_gentry gentry;
	174	void __user arg = (void __user ) __arg;
	175
	176	switch (cmd) {
	177	case MTRRIOC_ADD_ENTRY:
	178	case MTRRIOC_SET_ENTRY:
	179	case MTRRIOC_DEL_ENTRY:
	180	case MTRRIOC_KILL_ENTRY:
	181	case MTRRIOC_ADD_PAGE_ENTRY:
	182	case MTRRIOC_SET_PAGE_ENTRY:
	183	case MTRRIOC_DEL_PAGE_ENTRY:
	184	case MTRRIOC_KILL_PAGE_ENTRY:
	185	if (copy_from_user(&sentry, arg, sizeof sentry))
	186	return -EFAULT;
	187	break;
	188	case MTRRIOC_GET_ENTRY:
	189	case MTRRIOC_GET_PAGE_ENTRY:
	190	if (copy_from_user(&gentry, arg, sizeof gentry))
	191	return -EFAULT;
	192	break;
	193	#ifdef CONFIG_COMPAT
	194	case MTRRIOC32_ADD_ENTRY:
	195	case MTRRIOC32_SET_ENTRY:
	196	case MTRRIOC32_DEL_ENTRY:
	197	case MTRRIOC32_KILL_ENTRY:
	198	case MTRRIOC32_ADD_PAGE_ENTRY:
	199	case MTRRIOC32_SET_PAGE_ENTRY:
	200	case MTRRIOC32_DEL_PAGE_ENTRY:
	201	case MTRRIOC32_KILL_PAGE_ENTRY: {
	202	struct mtrr_sentry32 __user *s32;
	203
	204	s32 = (struct mtrr_sentry32 __user *)__arg;
	205	err = get_user(sentry.base, &s32->base);
	206	err \|= get_user(sentry.size, &s32->size);
	207	err \|= get_user(sentry.type, &s32->type);
	208	if (err)
	209	return err;
	210	break;
	211	}
	212	case MTRRIOC32_GET_ENTRY:
	213	case MTRRIOC32_GET_PAGE_ENTRY: {
	214	struct mtrr_gentry32 __user *g32;
	215
	216	g32 = (struct mtrr_gentry32 __user *)__arg;
	217	err = get_user(gentry.regnum, &g32->regnum);
	218	err \|= get_user(gentry.base, &g32->base);
	219	err \|= get_user(gentry.size, &g32->size);
	220	err \|= get_user(gentry.type, &g32->type);
	221	if (err)
	222	return err;
	223	break;
	224	}
	225	#endif
	226	}
	227
	228	switch (cmd) {
	229	default:
	230	return -ENOTTY;
	231	case MTRRIOC_ADD_ENTRY:
	232	#ifdef CONFIG_COMPAT
	233	case MTRRIOC32_ADD_ENTRY:
	234	#endif
	235	if (!capable(CAP_SYS_ADMIN))
	236	return -EPERM;
	237	err =
	238	mtrr_file_add(sentry.base, sentry.size, sentry.type, true,
	239	file, 0);
	240	break;
	241	case MTRRIOC_SET_ENTRY:
	242	#ifdef CONFIG_COMPAT
	243	case MTRRIOC32_SET_ENTRY:
	244	#endif
	245	if (!capable(CAP_SYS_ADMIN))
	246	return -EPERM;
	247	err = mtrr_add(sentry.base, sentry.size, sentry.type, false);
	248	break;
	249	case MTRRIOC_DEL_ENTRY:
	250	#ifdef CONFIG_COMPAT
	251	case MTRRIOC32_DEL_ENTRY:
	252	#endif
	253	if (!capable(CAP_SYS_ADMIN))
	254	return -EPERM;
	255	err = mtrr_file_del(sentry.base, sentry.size, file, 0);
	256	break;
	257	case MTRRIOC_KILL_ENTRY:
	258	#ifdef CONFIG_COMPAT
	259	case MTRRIOC32_KILL_ENTRY:
	260	#endif
	261	if (!capable(CAP_SYS_ADMIN))
	262	return -EPERM;
	263	err = mtrr_del(-1, sentry.base, sentry.size);
	264	break;
	265	case MTRRIOC_GET_ENTRY:
	266	#ifdef CONFIG_COMPAT
	267	case MTRRIOC32_GET_ENTRY:
	268	#endif
	269	if (gentry.regnum >= num_var_ranges)
	270	return -EINVAL;
	271	mtrr_if->get(gentry.regnum, &base, &size, &type);
	272
	273	/* Hide entries that go above 4GB */
	274	if (base + size - 1 >= (1UL << (8 * sizeof(gentry.size) - PAGE_SHIFT))
	275	\|\| size >= (1UL << (8 * sizeof(gentry.size) - PAGE_SHIFT)))
	276	gentry.base = gentry.size = gentry.type = 0;
	277	else {
	278	gentry.base = base << PAGE_SHIFT;
	279	gentry.size = size << PAGE_SHIFT;
	280	gentry.type = type;
	281	}
	282
	283	break;
	284	case MTRRIOC_ADD_PAGE_ENTRY:
	285	#ifdef CONFIG_COMPAT
	286	case MTRRIOC32_ADD_PAGE_ENTRY:
	287	#endif
	288	if (!capable(CAP_SYS_ADMIN))
	289	return -EPERM;
	290	err =
	291	mtrr_file_add(sentry.base, sentry.size, sentry.type, true,
	292	file, 1);
	293	break;
	294	case MTRRIOC_SET_PAGE_ENTRY:
	295	#ifdef CONFIG_COMPAT
	296	case MTRRIOC32_SET_PAGE_ENTRY:
	297	#endif
	298	if (!capable(CAP_SYS_ADMIN))
	299	return -EPERM;
	300	err =
	301	mtrr_add_page(sentry.base, sentry.size, sentry.type, false);
	302	break;
	303	case MTRRIOC_DEL_PAGE_ENTRY:
	304	#ifdef CONFIG_COMPAT
	305	case MTRRIOC32_DEL_PAGE_ENTRY:
	306	#endif
	307	if (!capable(CAP_SYS_ADMIN))
	308	return -EPERM;
	309	err = mtrr_file_del(sentry.base, sentry.size, file, 1);
	310	break;
	311	case MTRRIOC_KILL_PAGE_ENTRY:
	312	#ifdef CONFIG_COMPAT
	313	case MTRRIOC32_KILL_PAGE_ENTRY:
	314	#endif
	315	if (!capable(CAP_SYS_ADMIN))
	316	return -EPERM;
	317	err = mtrr_del_page(-1, sentry.base, sentry.size);
	318	break;
	319	case MTRRIOC_GET_PAGE_ENTRY:
	320	#ifdef CONFIG_COMPAT
	321	case MTRRIOC32_GET_PAGE_ENTRY:
	322	#endif
	323	if (gentry.regnum >= num_var_ranges)
	324	return -EINVAL;
	325	mtrr_if->get(gentry.regnum, &base, &size, &type);
	326	/* Hide entries that would overflow */
	327	if (size != (__typeof__(gentry.size))size)
	328	gentry.base = gentry.size = gentry.type = 0;
	329	else {
	330	gentry.base = base;
	331	gentry.size = size;
	332	gentry.type = type;
	333	}
	334	break;
	335	}
	336
	337	if (err)
	338	return err;
	339
	340	switch (cmd) {
	341	case MTRRIOC_GET_ENTRY:
	342	case MTRRIOC_GET_PAGE_ENTRY:
	343	if (copy_to_user(arg, &gentry, sizeof gentry))
	344	err = -EFAULT;
	345	break;
	346	#ifdef CONFIG_COMPAT
	347	case MTRRIOC32_GET_ENTRY:
	348	case MTRRIOC32_GET_PAGE_ENTRY: {
	349	struct mtrr_gentry32 __user *g32;
	350
	351	g32 = (struct mtrr_gentry32 __user *)__arg;
	352	err = put_user(gentry.base, &g32->base);
	353	err \|= put_user(gentry.size, &g32->size);
	354	err \|= put_user(gentry.regnum, &g32->regnum);
	355	err \|= put_user(gentry.type, &g32->type);
	356	break;
	357	}
	358	#endif
	359	}
	360	return err;
	361	}
	362
	363	static int mtrr_close(struct inode ino, struct file file)
	364	{
	365	unsigned int *fcount = FILE_FCOUNT(file);
	366	int i, max;
	367
	368	if (fcount != NULL) {
	369	max = num_var_ranges;
	370	for (i = 0; i < max; ++i) {
	371	while (fcount[i] > 0) {
	372	mtrr_del(i, 0, 0);
	373	--fcount[i];
	374	}
	375	}
	376	kfree(fcount);
	377	FILE_FCOUNT(file) = NULL;
	378	}
	379	return single_release(ino, file);
	380	}
	381
	382	static int mtrr_seq_show(struct seq_file seq, void offset);
	383
	384	static int mtrr_open(struct inode inode, struct file file)
	385	{
	386	if (!mtrr_if)
	387	return -EIO;
	388	if (!mtrr_if->get)
	389	return -ENXIO;
	390	return single_open(file, mtrr_seq_show, NULL);
	391	}
	392
	393	static const struct file_operations mtrr_fops = {
	394	.owner = THIS_MODULE,
	395	.open = mtrr_open,
	396	.read = seq_read,
	397	.llseek = seq_lseek,
	398	.write = mtrr_write,
	399	.unlocked_ioctl = mtrr_ioctl,
	400	.compat_ioctl = mtrr_ioctl,
	401	.release = mtrr_close,
	402	};
	403
	404	static int mtrr_seq_show(struct seq_file seq, void offset)
	405	{
	406	char factor;
	407	int i, max, len;
	408	mtrr_type type;
	409	unsigned long base, size;
	410
	411	len = 0;
	412	max = num_var_ranges;
	413	for (i = 0; i < max; i++) {
	414	mtrr_if->get(i, &base, &size, &type);
	415	if (size == 0) {
	416	mtrr_usage_table[i] = 0;
	417	continue;
	418	}
	419	if (size < (0x100000 >> PAGE_SHIFT)) {
	420	/* less than 1MB */
	421	factor = 'K';
	422	size <<= PAGE_SHIFT - 10;
	423	} else {
	424	factor = 'M';
	425	size >>= 20 - PAGE_SHIFT;
	426	}
	427	/* Base can be > 32bit */
	428	len += seq_printf(seq, "reg%02i: base=0x%06lx000 "
	429	"(%5luMB), size=%5lu%cB, count=%d: %s\n",
	430	i, base, base >> (20 - PAGE_SHIFT), size,
	431	factor, mtrr_usage_table[i],
	432	mtrr_attrib_to_str(type));
	433	}
	434	return 0;
	435	}
	436
	437	static int __init mtrr_if_init(void)
	438	{
	439	struct cpuinfo_x86 *c = &boot_cpu_data;
	440
	441	if ((!cpu_has(c, X86_FEATURE_MTRR)) &&
	442	(!cpu_has(c, X86_FEATURE_K6_MTRR)) &&
	443	(!cpu_has(c, X86_FEATURE_CYRIX_ARR)) &&
	444	(!cpu_has(c, X86_FEATURE_CENTAUR_MCR)))
	445	return -ENODEV;
	446
	447	proc_create("mtrr", S_IWUSR \| S_IRUGO, NULL, &mtrr_fops);
	448	return 0;
	449	}
	450	arch_initcall(mtrr_if_init);
	451	#endif /* CONFIG_PROC_FS */