summaryrefslogtreecommitdiffstats
path: root/include/linux/input-polldev.h
diff options
context:
space:
mode:
Diffstat (limited to 'include/linux/input-polldev.h')
0 files changed, 0 insertions, 0 deletions
/a> 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448
// SPDX-License-Identifier: GPL-2.0
/*
 *  Standard user space access functions based on mvcp/mvcs and doing
 *  interesting things in the secondary space mode.
 *
 *    Copyright IBM Corp. 2006,2014
 *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
 *		 Gerald Schaefer (gerald.schaefer@de.ibm.com)
 */

#include <linux/jump_label.h>
#include <linux/uaccess.h>
#include <linux/export.h>
#include <linux/errno.h>
#include <linux/mm.h>
#include <asm/mmu_context.h>
#include <asm/facility.h>

#ifndef CONFIG_HAVE_MARCH_Z10_FEATURES
static DEFINE_STATIC_KEY_FALSE(have_mvcos);

static int __init uaccess_init(void)
{
	if (test_facility(27))
		static_branch_enable(&have_mvcos);
	return 0;
}
early_initcall(uaccess_init);

static inline int copy_with_mvcos(void)
{
	if (static_branch_likely(&have_mvcos))
		return 1;
	return 0;
}
#else
static inline int copy_with_mvcos(void)
{
	return 1;
}
#endif

void set_fs(mm_segment_t fs)
{
	current->thread.mm_segment = fs;
	if (fs == USER_DS) {
		__ctl_load(S390_lowcore.user_asce, 1, 1);
		clear_cpu_flag(CIF_ASCE_PRIMARY);
	} else {
		__ctl_load(S390_lowcore.kernel_asce, 1, 1);
		set_cpu_flag(CIF_ASCE_PRIMARY);
	}
	if (fs & 1) {
		if (fs == USER_DS_SACF)
			__ctl_load(S390_lowcore.user_asce, 7, 7);
		else
			__ctl_load(S390_lowcore.kernel_asce, 7, 7);
		set_cpu_flag(CIF_ASCE_SECONDARY);
	}
}
EXPORT_SYMBOL(set_fs);

mm_segment_t enable_sacf_uaccess(void)
{
	mm_segment_t old_fs;
	unsigned long asce, cr;
	unsigned long flags;

	old_fs = current->thread.mm_segment;
	if (old_fs & 1)
		return old_fs;
	/* protect against a concurrent page table upgrade */
	local_irq_save(flags);
	current->thread.mm_segment |= 1;
	asce = S390_lowcore.kernel_asce;
	if (likely(old_fs == USER_DS)) {
		__ctl_store(cr, 1, 1);
		if (cr != S390_lowcore.kernel_asce) {
			__ctl_load(S390_lowcore.kernel_asce, 1, 1);
			set_cpu_flag(CIF_ASCE_PRIMARY);
		}
		asce = S390_lowcore.user_asce;
	}
	__ctl_store(cr, 7, 7);
	if (cr != asce) {
		__ctl_load(asce, 7, 7);
		set_cpu_flag(CIF_ASCE_SECONDARY);
	}
	local_irq_restore(flags);
	return old_fs;
}
EXPORT_SYMBOL(enable_sacf_uaccess);

void disable_sacf_uaccess(mm_segment_t old_fs)
{
	current->thread.mm_segment = old_fs;
	if (old_fs == USER_DS && test_facility(27)) {
		__ctl_load(S390_lowcore.user_asce, 1, 1);
		clear_cpu_flag(CIF_ASCE_PRIMARY);
	}
}
EXPORT_SYMBOL(disable_sacf_uaccess);

static inline unsigned long copy_from_user_mvcos(void *x, const void __user *ptr,
						 unsigned long size)
{
	register unsigned long reg0 asm("0") = 0x01UL;
	unsigned long tmp1, tmp2;

	tmp1 = -4096UL;
	asm volatile(
		"0: .insn ss,0xc80000000000,0(%0,%2),0(%1),0\n"
		"6: jz    4f\n"
		"1: algr  %0,%3\n"
		"   slgr  %1,%3\n"
		"   slgr  %2,%3\n"
		"   j     0b\n"
		"2: la    %4,4095(%1)\n"/* %4 = ptr + 4095 */
		"   nr    %4,%3\n"	/* %4 = (ptr + 4095) & -4096 */
		"   slgr  %4,%1\n"
		"   clgr  %0,%4\n"	/* copy crosses next page boundary? */
		"   jnh   5f\n"
		"3: .insn ss,0xc80000000000,0(%4,%2),0(%1),0\n"
		"7: slgr  %0,%4\n"
		"   j     5f\n"
		"4: slgr  %0,%0\n"
		"5:\n"
		EX_TABLE(0b,2b) EX_TABLE(3b,5b) EX_TABLE(6b,2b) EX_TABLE(7b,5b)
		: "+a" (size), "+a" (ptr), "+a" (x), "+a" (tmp1), "=a" (tmp2)
		: "d" (reg0) : "cc", "memory");
	return size;
}

static inline unsigned long copy_from_user_mvcp(void *x, const void __user *ptr,
						unsigned long size)
{
	unsigned long tmp1, tmp2;
	mm_segment_t old_fs;

	old_fs = enable_sacf_uaccess();
	tmp1 = -256UL;
	asm volatile(
		"   sacf  0\n"
		"0: mvcp  0(%0,%2),0(%1),%3\n"
		"7: jz    5f\n"
		"1: algr  %0,%3\n"
		"   la    %1,256(%1)\n"
		"   la    %2,256(%2)\n"
		"2: mvcp  0(%0,%2),0(%1),%3\n"
		"8: jnz   1b\n"
		"   j     5f\n"
		"3: la    %4,255(%1)\n"	/* %4 = ptr + 255 */
		"   lghi  %3,-4096\n"
		"   nr    %4,%3\n"	/* %4 = (ptr + 255) & -4096 */
		"   slgr  %4,%1\n"
		"   clgr  %0,%4\n"	/* copy crosses next page boundary? */
		"   jnh   6f\n"
		"4: mvcp  0(%4,%2),0(%1),%3\n"
		"9: slgr  %0,%4\n"
		"   j     6f\n"
		"5: slgr  %0,%0\n"
		"6: sacf  768\n"
		EX_TABLE(0b,3b) EX_TABLE(2b,3b) EX_TABLE(4b,6b)
		EX_TABLE(7b,3b) EX_TABLE(8b,3b) EX_TABLE(9b,6b)
		: "+a" (size), "+a" (ptr), "+a" (x), "+a" (tmp1), "=a" (tmp2)
		: : "cc", "memory");
	disable_sacf_uaccess(old_fs);
	return size;
}

unsigned long raw_copy_from_user(void *to, const void __user *from, unsigned long n)
{
	if (copy_with_mvcos())
		return copy_from_user_mvcos(to, from, n);
	return copy_from_user_mvcp(to, from, n);
}
EXPORT_SYMBOL(raw_copy_from_user);

static inline unsigned long copy_to_user_mvcos(void __user *ptr, const void *x,
					       unsigned long size)
{
	register unsigned long reg0 asm("0") = 0x010000UL;
	unsigned long tmp1, tmp2;

	tmp1 = -4096UL;
	asm volatile(
		"0: .insn ss,0xc80000000000,0(%0,%1),0(%2),0\n"
		"6: jz    4f\n"
		"1: algr  %0,%3\n"
		"   slgr  %1,%3\n"
		"   slgr  %2,%3\n"
		"   j     0b\n"
		"2: la    %4,4095(%1)\n"/* %4 = ptr + 4095 */
		"   nr    %4,%3\n"	/* %4 = (ptr + 4095) & -4096 */
		"   slgr  %4,%1\n"
		"   clgr  %0,%4\n"	/* copy crosses next page boundary? */
		"   jnh   5f\n"
		"3: .insn ss,0xc80000000000,0(%4,%1),0(%2),0\n"
		"7: slgr  %0,%4\n"
		"   j     5f\n"
		"4: slgr  %0,%0\n"
		"5:\n"
		EX_TABLE(0b,2b) EX_TABLE(3b,5b) EX_TABLE(6b,2b) EX_TABLE(7b,5b)
		: "+a" (size), "+a" (ptr), "+a" (x), "+a" (tmp1), "=a" (tmp2)
		: "d" (reg0) : "cc", "memory");
	return size;
}

static inline unsigned long copy_to_user_mvcs(void __user *ptr, const void *x,
					      unsigned long size)
{
	unsigned long tmp1, tmp2;
	mm_segment_t old_fs;

	old_fs = enable_sacf_uaccess();
	tmp1 = -256UL;
	asm volatile(
		"   sacf  0\n"
		"0: mvcs  0(%0,%1),0(%2),%3\n"
		"7: jz    5f\n"
		"1: algr  %0,%3\n"
		"   la    %1,256(%1)\n"
		"   la    %2,256(%2)\n"
		"2: mvcs  0(%0,%1),0(%2),%3\n"
		"8: jnz   1b\n"
		"   j     5f\n"
		"3: la    %4,255(%1)\n" /* %4 = ptr + 255 */
		"   lghi  %3,-4096\n"
		"   nr    %4,%3\n"	/* %4 = (ptr + 255) & -4096 */
		"   slgr  %4,%1\n"
		"   clgr  %0,%4\n"	/* copy crosses next page boundary? */
		"   jnh   6f\n"
		"4: mvcs  0(%4,%1),0(%2),%3\n"
		"9: slgr  %0,%4\n"
		"   j     6f\n"
		"5: slgr  %0,%0\n"
		"6: sacf  768\n"
		EX_TABLE(0b,3b) EX_TABLE(2b,3b) EX_TABLE(4b,6b)
		EX_TABLE(7b,3b) EX_TABLE(8b,3b) EX_TABLE(9b,6b)
		: "+a" (size), "+a" (ptr), "+a" (x), "+a" (tmp1), "=a" (tmp2)
		: : "cc", "memory");
	disable_sacf_uaccess(old_fs);
	return size;
}

unsigned long raw_copy_to_user(void __user *to, const void *from, unsigned long n)
{
	if (copy_with_mvcos())
		return copy_to_user_mvcos(to, from, n);
	return copy_to_user_mvcs(to, from, n);
}
EXPORT_SYMBOL(raw_copy_to_user);

static inline unsigned long copy_in_user_mvcos(void __user *to, const void __user *from,
					       unsigned long size)
{
	register unsigned long reg0 asm("0") = 0x010001UL;
	unsigned long tmp1, tmp2;

	tmp1 = -4096UL;
	/* FIXME: copy with reduced length. */
	asm volatile(
		"0: .insn ss,0xc80000000000,0(%0,%1),0(%2),0\n"
		"   jz	  2f\n"
		"1: algr  %0,%3\n"
		"   slgr  %1,%3\n"
		"   slgr  %2,%3\n"
		"   j	  0b\n"
		"2:slgr  %0,%0\n"
		"3: \n"
		EX_TABLE(0b,3b)
		: "+a" (size), "+a" (to), "+a" (from), "+a" (tmp1), "=a" (tmp2)
		: "d" (reg0) : "cc", "memory");
	return size;
}

static inline unsigned long copy_in_user_mvc(void __user *to, const void __user *from,
					     unsigned long size)
{
	mm_segment_t old_fs;
	unsigned long tmp1;

	old_fs = enable_sacf_uaccess();
	asm volatile(
		"   sacf  256\n"
		"   aghi  %0,-1\n"
		"   jo	  5f\n"
		"   bras  %3,3f\n"
		"0: aghi  %0,257\n"
		"1: mvc	  0(1,%1),0(%2)\n"
		"   la	  %1,1(%1)\n"
		"   la	  %2,1(%2)\n"
		"   aghi  %0,-1\n"
		"   jnz	  1b\n"
		"   j	  5f\n"
		"2: mvc	  0(256,%1),0(%2)\n"
		"   la	  %1,256(%1)\n"
		"   la	  %2,256(%2)\n"
		"3: aghi  %0,-256\n"
		"   jnm	  2b\n"
		"4: ex	  %0,1b-0b(%3)\n"
		"5: slgr  %0,%0\n"
		"6: sacf  768\n"
		EX_TABLE(1b,6b) EX_TABLE(2b,0b) EX_TABLE(4b,0b)
		: "+a" (size), "+a" (to), "+a" (from), "=a" (tmp1)
		: : "cc", "memory");
	disable_sacf_uaccess(old_fs);
	return size;
}

unsigned long raw_copy_in_user(void __user *to, const void __user *from, unsigned long n)
{
	if (copy_with_mvcos())
		return copy_in_user_mvcos(to, from, n);
	return copy_in_user_mvc(to, from, n);
}
EXPORT_SYMBOL(raw_copy_in_user);

static inline unsigned long clear_user_mvcos(void __user *to, unsigned long size)
{
	register unsigned long reg0 asm("0") = 0x010000UL;
	unsigned long tmp1, tmp2;

	tmp1 = -4096UL;
	asm volatile(
		"0: .insn ss,0xc80000000000,0(%0,%1),0(%4),0\n"
		"   jz	  4f\n"
		"1: algr  %0,%2\n"
		"   slgr  %1,%2\n"
		"   j	  0b\n"
		"2: la	  %3,4095(%1)\n"/* %4 = to + 4095 */
		"   nr	  %3,%2\n"	/* %4 = (to + 4095) & -4096 */
		"   slgr  %3,%1\n"
		"   clgr  %0,%3\n"	/* copy crosses next page boundary? */
		"   jnh	  5f\n"
		"3: .insn ss,0xc80000000000,0(%3,%1),0(%4),0\n"
		"   slgr  %0,%3\n"
		"   j	  5f\n"
		"4: slgr  %0,%0\n"
		"5:\n"
		EX_TABLE(0b,2b) EX_TABLE(3b,5b)
		: "+a" (size), "+a" (to), "+a" (tmp1), "=a" (tmp2)
		: "a" (empty_zero_page), "d" (reg0) : "cc", "memory");
	return size;
}

static inline unsigned long clear_user_xc(void __user *to, unsigned long size)
{
	mm_segment_t old_fs;
	unsigned long tmp1, tmp2;

	old_fs = enable_sacf_uaccess();
	asm volatile(
		"   sacf  256\n"
		"   aghi  %0,-1\n"
		"   jo    5f\n"
		"   bras  %3,3f\n"
		"   xc    0(1,%1),0(%1)\n"
		"0: aghi  %0,257\n"
		"   la    %2,255(%1)\n" /* %2 = ptr + 255 */
		"   srl   %2,12\n"
		"   sll   %2,12\n"	/* %2 = (ptr + 255) & -4096 */
		"   slgr  %2,%1\n"
		"   clgr  %0,%2\n"	/* clear crosses next page boundary? */
		"   jnh   5f\n"
		"   aghi  %2,-1\n"
		"1: ex    %2,0(%3)\n"
		"   aghi  %2,1\n"
		"   slgr  %0,%2\n"
		"   j     5f\n"
		"2: xc    0(256,%1),0(%1)\n"
		"   la    %1,256(%1)\n"
		"3: aghi  %0,-256\n"
		"   jnm   2b\n"
		"4: ex    %0,0(%3)\n"
		"5: slgr  %0,%0\n"
		"6: sacf  768\n"
		EX_TABLE(1b,6b) EX_TABLE(2b,0b) EX_TABLE(4b,0b)
		: "+a" (size), "+a" (to), "=a" (tmp1), "=a" (tmp2)
		: : "cc", "memory");
	disable_sacf_uaccess(old_fs);
	return size;
}

unsigned long __clear_user(void __user *to, unsigned long size)
{
	if (copy_with_mvcos())
			return clear_user_mvcos(to, size);
	return clear_user_xc(to, size);
}
EXPORT_SYMBOL(__clear_user);

static inline unsigned long strnlen_user_srst(const char __user *src,
					      unsigned long size)
{
	register unsigned long reg0 asm("0") = 0;
	unsigned long tmp1, tmp2;

	asm volatile(
		"   la    %2,0(%1)\n"
		"   la    %3,0(%0,%1)\n"
		"   slgr  %0,%0\n"
		"   sacf  256\n"
		"0: srst  %3,%2\n"
		"   jo    0b\n"
		"   la    %0,1(%3)\n"	/* strnlen_user results includes \0 */
		"   slgr  %0,%1\n"
		"1: sacf  768\n"
		EX_TABLE(0b,1b)
		: "+a" (size), "+a" (src), "=a" (tmp1), "=a" (tmp2)
		: "d" (reg0) : "cc", "memory");
	return size;
}

unsigned long __strnlen_user(const char __user *src, unsigned long size)
{
	mm_segment_t old_fs;
	unsigned long len;

	if (unlikely(!size))
		return 0;
	old_fs = enable_sacf_uaccess();
	len = strnlen_user_srst(src, size);
	disable_sacf_uaccess(old_fs);
	return len;
}
EXPORT_SYMBOL(__strnlen_user);

long __strncpy_from_user(char *dst, const char __user *src, long size)
{
	size_t done, len, offset, len_str;

	if (unlikely(size <= 0))
		return 0;
	done = 0;
	do {
		offset = (size_t)src & (L1_CACHE_BYTES - 1);
		len = min(size - done, L1_CACHE_BYTES - offset);
		if (copy_from_user(dst, src, len))
			return -EFAULT;
		len_str = strnlen(dst, len);
		done += len_str;
		src += len_str;
		dst += len_str;
	} while ((len_str == len) && (done < size));
	return done;
}
EXPORT_SYMBOL(__strncpy_from_user);