/* * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) * * 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. * * vineetg: June 2010 * -__clear_user( ) called multiple times during elf load was byte loop * converted to do as much word clear as possible. * * vineetg: Dec 2009 * -Hand crafted constant propagation for "constant" copy sizes * -stock kernel shrunk by 33K at -O3 * * vineetg: Sept 2009 * -Added option to (UN)inline copy_(to|from)_user to reduce code sz * -kernel shrunk by 200K even at -O3 (gcc 4.2.1) * -Enabled when doing -Os * * Amit Bhor, Sameer Dhavale: Codito Technologies 2004 */ #ifndef _ASM_ARC_UACCESS_H #define _ASM_ARC_UACCESS_H #include <linux/sched.h> #include <asm/errno.h> #include <linux/string.h> /* for generic string functions */ #define __kernel_ok (segment_eq(get_fs(), KERNEL_DS)) /* * Algorthmically, for __user_ok() we want do: * (start < TASK_SIZE) && (start+len < TASK_SIZE) * where TASK_SIZE could either be retrieved from thread_info->addr_limit or * emitted directly in code. * * This can however be rewritten as follows: * (len <= TASK_SIZE) && (start+len < TASK_SIZE) * * Because it essentially checks if buffer end is within limit and @len is * non-ngeative, which implies that buffer start will be within limit too. * * The reason for rewriting being, for majority of cases, @len is generally * compile time constant, causing first sub-expression to be compile time * subsumed. * * The second part would generate weird large LIMMs e.g. (0x6000_0000 - 0x10), * so we check for TASK_SIZE using get_fs() since the addr_limit load from mem * would already have been done at this call site for __kernel_ok() * */ #define __user_ok(addr, sz) (((sz) <= TASK_SIZE) && \ ((addr) <= (get_fs() - (sz)))) #define __access_ok(addr, sz) (unlikely(__kernel_ok) || \ likely(__user_ok((addr), (sz)))) /*********** Single byte/hword/word copies ******************/ #define __get_user_fn(sz, u, k) \ ({ \ long __ret = 0; /* success by default */ \ switch (sz) { \ case 1: __arc_get_user_one(*(k), u, "ldb", __ret); break; \ case 2: __arc_get_user_one(*(k), u, "ldw", __ret); break; \ case 4: __arc_get_user_one(*(k), u, "ld", __ret); break; \ case 8: __arc_get_user_one_64(*(k), u, __ret); break; \ } \ __ret; \ }) /* * Returns 0 on success, -EFAULT if not. * @ret already contains 0 - given that errors will be less likely * (hence +r asm constraint below). * In case of error, fixup code will make it -EFAULT */ #define __arc_get_user_one(dst, src, op, ret) \ __asm__ __volatile__( \ "1: "op" %1,[%2]\n" \ "2: ;nop\n" \ " .section .fixup, \"ax\"\n" \ " .align 4\n" \ "3: mov %0, %3\n" \ " j 2b\n" \ " .previous\n" \ " .section __ex_table, \"a\"\n" \ " .align 4\n" \ " .word 1b,3b\n" \ " .previous\n" \ \ : "+r" (ret), "=r" (dst) \ : "r" (src), "ir" (-EFAULT)) #define __arc_get_user_one_64(dst, src, ret) \ __asm__ __volatile__( \ "1: ld %1,[%2]\n" \ "4: ld %R1,[%2, 4]\n" \ "2: ;nop\n" \ " .section .fixup, \"ax\"\n" \ " .align 4\n" \ "3: mov %0, %3\n" \ " j 2b\n" \ " .previous\n" \ " .section __ex_table, \"a\"\n" \ " .align 4\n" \ " .word 1b,3b\n" \ " .word 4b,3b\n" \ " .previous\n" \ \ : "+r" (ret), "=r" (dst) \ : "r" (src), "ir" (-EFAULT)) #define __put_user_fn(sz, u, k) \ ({ \ long __ret = 0; /* success by default */ \ switch (sz) { \ case 1: __arc_put_user_one(*(k), u, "stb", __ret); break; \ case 2: __arc_put_user_one(*(k), u, "stw", __ret); break; \ case 4: __arc_put_user_one(*(k), u, "st", __ret); break; \ case 8: __arc_put_user_one_64(*(k), u, __ret); break; \ } \ __ret; \ }) #define __arc_put_user_one(src, dst, op, ret) \ __asm__ __volatile__( \ "1: "op" %1,[%2]\n" \ "2: ;nop\n" \ " .section .fixup, \"ax\"\n" \ " .align 4\n" \ "3: mov %0, %3\n" \ " j 2b\n" \ " .previous\n" \ " .section __ex_table, \"a\"\n" \ " .align 4\n" \ " .word 1b,3b\n" \ " .previous\n" \ \ : "+r" (ret) \ : "r" (src), "r" (dst), "ir" (-EFAULT)) #define __arc_put_user_one_64(src, dst, ret) \ __asm__ __volatile__( \ "1: st %1,[%2]\n" \ "4: st %R1,[%2, 4]\n" \ "2: ;nop\n" \ " .section .fixup, \"ax\"\n" \ " .align 4\n" \ "3: mov %0, %3\n" \ " j 2b\n" \ " .previous\n" \ " .section __ex_table, \"a\"\n" \ " .align 4\n" \ " .word 1b,3b\n" \ " .word 4b,3b\n" \ " .previous\n" \ \ : "+r" (ret) \ : "r" (src), "r" (dst), "ir" (-EFAULT)) static inline unsigned long __arc_copy_from_user(void *to, const void __user *from, unsigned long n) { long res = 0; char val; unsigned long tmp1, tmp2, tmp3, tmp4; unsigned long orig_n = n; if (n == 0) return 0; /* unaligned */ if (((unsigned long)to & 0x3) || ((unsigned long)from & 0x3)) { unsigned char tmp; __asm__ __volatile__ ( " mov.f lp_count, %0 \n" " lpnz 2f \n" "1: ldb.ab %1, [%3, 1] \n" " stb.ab %1, [%2, 1] \n" " sub %0,%0,1 \n" "2: ;nop \n" " .section .fixup, \"ax\" \n" " .align 4 \n" "3: j 2b \n" " .previous \n" " .section __ex_table, \"a\" \n" " .align 4 \n" " .word 1b, 3b \n" " .previous \n" : "+r" (n), /* * Note as an '&' earlyclobber operand to make sure the * temporary register inside the loop is not the same as * FROM or TO. */ "=&r" (tmp), "+r" (to), "+r" (from) : : "lp_count", "lp_start", "lp_end", "memory"); return n; } /* * Hand-crafted constant propagation to reduce code sz of the * laddered copy 16x,8,4,2,1 */ if (__builtin_constant_p(orig_n)) { res = orig_n; if (orig_n / 16) { orig_n = orig_n % 16; __asm__ __volatile__( " lsr lp_count, %7,4 \n" " lp 3f \n" "1: ld.ab %3, [%2, 4] \n" "11: ld.ab %4, [%2, 4] \n" "12: ld.ab %5, [%2, 4] \n" "13: ld.ab %6, [%2, 4] \n" " st.ab %3, [%1, 4] \n" " st.ab %4, [%1, 4] \n" " st.ab %5, [%1, 4] \n" " st.ab %6, [%1, 4] \n" " sub %0,%0,16 \n" "3: ;nop \n" " .section .fixup, \"ax\" \n" " .align 4 \n" "4: j 3b \n" " .previous \n" " .section __ex_table, \"a\" \n" " .align 4 \n" " .word 1b, 4b \n" " .word 11b,4b \n" " .word 12b,4b \n" " .word 13b,4b \n" " .previous \n" : "+r" (res), "+r"(to), "+r"(from), "=r"(tmp1), "=r"(tmp2), "=r"(tmp3), "=r"(tmp4) : "ir"(n) : "lp_count", "memory"); } if (orig_n / 8) { orig_n = orig_n % 8; __asm__ __volatile__( "14: ld.ab %3, [%2,4] \n" "15: ld.ab %4, [%2,4] \n" " st.ab %3, [%1,4] \n" " st.ab %4, [%1,4] \n" " sub %0,%0,8 \n" "31: ;nop \n" " .section .fixup, \"ax\" \n" " .align 4 \n" "4: j 31b \n" " .previous \n" " .section __ex_table, \"a\" \n" " .align 4 \n" " .word 14b,4b \n" " .word 15b,4b \n" " .previous \n" : "+r" (res), "+r"(to), "+r"(from), "=r"(tmp1), "=r"(tmp2) : : "memory"); } if (orig_n / 4) { orig_n = orig_n % 4; __asm__ __volatile__( "16: ld.ab %3, [%2,4] \n" " st.ab %3, [%1,4] \n" " sub %0,%0,4 \n" "32: ;nop \n" " .section .fixup, \"ax\" \n" " .align 4 \n" "4: j 32b \n" " .previous \n" " .section __ex_table, \"a\" \n" " .align 4 \n" " .word 16b,4b \n" " .previous \n" : "+r" (res), "+r"(to), "+r"(from), "=r"(tmp1) : : "memory"); } if (orig_n / 2) { orig_n = orig_n % 2; __asm__ __volatile__( "17: ldw.ab %3, [%2,2] \n" " stw.ab %3, [%1,2] \n" " sub %0,%0,2 \n" "33: ;nop \n" " .section .fixup, \"ax\" \n" " .align 4 \n" "4: j 33b \n" " .previous \n" " .section __ex_table, \"a\" \n" " .align 4 \n" " .word 17b,4b \n" " .previous \n" : "+r" (res), "+r"(to), "+r"(from), "=r"(tmp1) : : "memory"); } if (orig_n & 1) { __asm__ __volatile__( "18: ldb.ab %3, [%2,2] \n" " stb.ab %3, [%1,2] \n" " sub %0,%0,1 \n" "34: ; nop \n" " .section .fixup, \"ax\" \n" " .align 4 \n" "4: j 34b \n" " .previous \n" " .section __ex_table, \"a\" \n" " .align 4 \n" " .word 18b,4b \n" " .previous \n" : "+r" (res), "+r"(to), "+r"(from), "=r"(tmp1) : : "memory"); } } else { /* n is NOT constant, so laddered copy of 16x,8,4,2,1 */ __asm__ __volatile__( " mov %0,%3 \n" " lsr.f lp_count, %3,4 \n" /* 16x bytes */ " lpnz 3f \n" "1: ld.ab %5, [%2, 4] \n" "11: ld.ab %6, [%2, 4] \n" "12: ld.ab %7, [%2, 4] \n" "13: ld.ab %8, [%2, 4] \n" " st.ab %5, [%1, 4] \n" " st.ab %6, [%1, 4] \n" " st.ab %7, [%1, 4] \n" " st.ab %8, [%1, 4] \n" " sub %0,%0,16 \n" "3: and.f %3,%3,0xf \n" /* stragglers */ " bz 34f \n" " bbit0 %3,3,31f \n" /* 8 bytes left */ "14: ld.ab %5, [%2,4] \n" "15: ld.ab %6, [%2,4] \n" " st.ab %5, [%1,4] \n" " st.ab %6, [%1,4] \n" " sub.f %0,%0,8 \n" "31: bbit0 %3,2,32f \n" /* 4 bytes left */ "16: ld.ab %5, [%2,4] \n" " st.ab %5, [%1,4] \n" " sub.f %0,%0,4 \n" "32: bbit0 %3,1,33f \n" /* 2 bytes left */ "17: ldw.ab %5, [%2,2] \n" " stw.ab %5, [%1,2] \n" " sub.f %0,%0,2 \n" "33: bbit0 %3,0,34f \n" "18: ldb.ab %5, [%2,1] \n" /* 1 byte left */ " stb.ab %5, [%1,1] \n" " sub.f %0,%0,1 \n" "34: ;nop \n" " .section .fixup, \"ax\" \n" " .align 4 \n" "4: j 34b \n" " .previous \n" " .section __ex_table, \"a\" \n" " .align 4 \n" " .word 1b, 4b \n" " .word 11b,4b \n" " .word 12b,4b \n" " .word 13b,4b \n" " .word 14b,4b \n" " .word 15b,4b \n" " .word 16b,4b \n" " .word 17b,4b \n" " .word 18b,4b \n" " .previous \n" : "=r" (res), "+r"(to), "+r"(from), "+r"(n), "=r"(val), "=r"(tmp1), "=r"(tmp2), "=r"(tmp3), "=r"(tmp4) : : "lp_count", "memory"); } return res; } extern unsigned long slowpath_copy_to_user(void __user *to, const void *from, unsigned long n); static inline unsigned long __arc_copy_to_user(void __user *to, const void *from, unsigned long n) { long res = 0; char val; unsigned long tmp1, tmp2, tmp3, tmp4; unsigned long orig_n = n; if (n == 0) return 0; /* unaligned */ if (((unsigned long)to & 0x3) || ((unsigned long)from & 0x3)) { unsigned char tmp; __asm__ __volatile__( " mov.f lp_count, %0 \n" " lpnz 3f \n" " ldb.ab %1, [%3, 1] \n" "1: stb.ab %1, [%2, 1] \n" " sub %0, %0, 1 \n" "3: ;nop \n" " .section .fixup, \"ax\" \n" " .align 4 \n" "4: j 3b \n" " .previous \n" " .section __ex_table, \"a\" \n" " .align 4 \n" " .word 1b, 4b \n" " .previous \n" : "+r" (n), /* Note as an '&' earlyclobber operand to make sure the * temporary register inside the loop is not the same as * FROM or TO. */ "=&r" (tmp), "+r" (to), "+r" (from) : : "lp_count", "lp_start", "lp_end", "memory"); return n; } if (__builtin_constant_p(orig_n)) { res = orig_n; if (orig_n / 16) { orig_n = orig_n % 16; __asm__ __volatile__( " lsr lp_count, %7,4 \n" " lp 3f \n" " ld.ab %3, [%2, 4] \n" " ld.ab %4, [%2, 4] \n" " ld.ab %5, [%2, 4] \n" " ld.ab %6, [%2, 4] \n" "1: st.ab %3, [%1, 4] \n" "11: st.ab %4, [%1, 4] \n" "12: st.ab %5, [%1, 4] \n" "13: st.ab %6, [%1, 4] \n" " sub %0, %0, 16 \n" "3:;nop \n" " .section .fixup, \"ax\" \n" " .align 4 \n" "4: j 3b \n" " .previous \n" " .section __ex_table, \"a\" \n" " .align 4 \n" " .word 1b, 4b \n" " .word 11b,4b \n" " .word 12b,4b \n" " .word 13b,4b \n" " .previous \n" : "+r" (res), "+r"(to), "+r"(from), "=r"(tmp1), "=r"(tmp2), "=r"(tmp3), "=r"(tmp4) : "ir"(n) : "lp_count", "memory"); } if (orig_n / 8) { orig_n = orig_n % 8; __asm__ __volatile__( " ld.ab %3, [%2,4] \n" " ld.ab %4, [%2,4] \n" "14: st.ab %3, [%1,4] \n" "15: st.ab %4, [%1,4] \n" " sub %0, %0, 8 \n" "31:;nop \n" " .section .fixup, \"ax\" \n" " .align 4 \n" "4: j 31b \n" " .previous \n" " .section __ex_table, \"a\" \n" " .align 4 \n" " .word 14b,4b \n" " .word 15b,4b \n" " .previous \n" : "+r" (res), "+r"(to), "+r"(from), "=r"(tmp1), "=r"(tmp2) : : "memory"); } if (orig_n / 4) { orig_n = orig_n % 4; __asm__ __volatile__( " ld.ab %3, [%2,4] \n" "16: st.ab %3, [%1,4] \n" " sub %0, %0, 4 \n" "32:;nop \n" " .section .fixup, \"ax\" \n" " .align 4 \n" "4: j 32b \n" " .previous \n" " .section __ex_table, \"a\" \n" " .align 4 \n" " .word 16b,4b \n" " .previous \n" : "+r" (res), "+r"(to), "+r"(from), "=r"(tmp1) : : "memory"); } if (orig_n / 2) { orig_n = orig_n % 2; __asm__ __volatile__( " ldw.ab %3, [%2,2] \n" "17: stw.ab %3, [%1,2] \n" " sub %0, %0, 2 \n" "33:;nop \n" " .section .fixup, \"ax\" \n" " .align 4 \n" "4: j 33b \n" " .previous \n" " .section __ex_table, \"a\" \n" " .align 4 \n" " .word 17b,4b \n" " .previous \n" : "+r" (res), "+r"(to), "+r"(from), "=r"(tmp1) : : "memory"); } if (orig_n & 1) { __asm__ __volatile__( " ldb.ab %3, [%2,1] \n" "18: stb.ab %3, [%1,1] \n" " sub %0, %0, 1 \n" "34: ;nop \n" " .section .fixup, \"ax\" \n" " .align 4 \n" "4: j 34b \n" " .previous \n" " .section __ex_table, \"a\" \n" " .align 4 \n" " .word 18b,4b \n" " .previous \n" : "+r" (res), "+r"(to), "+r"(from), "=r"(tmp1) : : "memory"); } } else { /* n is NOT constant, so laddered copy of 16x,8,4,2,1 */ __asm__ __volatile__( " mov %0,%3 \n" " lsr.f lp_count, %3,4 \n" /* 16x bytes */ " lpnz 3f \n" " ld.ab %5, [%2, 4] \n" " ld.ab %6, [%2, 4] \n" " ld.ab %7, [%2, 4] \n" " ld.ab %8, [%2, 4] \n" "1: st.ab %5, [%1, 4] \n" "11: st.ab %6, [%1, 4] \n" "12: st.ab %7, [%1, 4] \n" "13: st.ab %8, [%1, 4] \n" " sub %0, %0, 16 \n" "3: and.f %3,%3,0xf \n" /* stragglers */ " bz 34f \n" " bbit0 %3,3,31f \n" /* 8 bytes left */ " ld.ab %5, [%2,4] \n" " ld.ab %6, [%2,4] \n" "14: st.ab %5, [%1,4] \n" "15: st.ab %6, [%1,4] \n" " sub.f %0, %0, 8 \n" "31: bbit0 %3,2,32f \n" /* 4 bytes left */ " ld.ab %5, [%2,4] \n" "16: st.ab %5, [%1,4] \n" " sub.f %0, %0, 4 \n" "32: bbit0 %3,1,33f \n" /* 2 bytes left */ " ldw.ab %5, [%2,2] \n" "17: stw.ab %5, [%1,2] \n" " sub.f %0, %0, 2 \n" "33: bbit0 %3,0,34f \n" " ldb.ab %5, [%2,1] \n" /* 1 byte left */ "18: stb.ab %5, [%1,1] \n" " sub.f %0, %0, 1 \n" "34: ;nop \n" " .section .fixup, \"ax\" \n" " .align 4 \n" "4: j 34b \n" " .previous \n" " .section __ex_table, \"a\" \n" " .align 4 \n" " .word 1b, 4b \n" " .word 11b,4b \n" " .word 12b,4b \n" " .word 13b,4b \n" " .word 14b,4b \n" " .word 15b,4b \n" " .word 16b,4b \n" " .word 17b,4b \n" " .word 18b,4b \n" " .previous \n" : "=r" (res), "+r"(to), "+r"(from), "+r"(n), "=r"(val), "=r"(tmp1), "=r"(tmp2), "=r"(tmp3), "=r"(tmp4) : : "lp_count", "memory"); } return res; } static inline unsigned long __arc_clear_user(void __user *to, unsigned long n) { long res = n; unsigned char *d_char = to; __asm__ __volatile__( " bbit0 %0, 0, 1f \n" "75: stb.ab %2, [%0,1] \n" " sub %1, %1, 1 \n" "1: bbit0 %0, 1, 2f \n" "76: stw.ab %2, [%0,2] \n" " sub %1, %1, 2 \n" "2: asr.f lp_count, %1, 2 \n" " lpnz 3f \n" "77: st.ab %2, [%0,4] \n" " sub %1, %1, 4 \n" "3: bbit0 %1, 1, 4f \n" "78: stw.ab %2, [%0,2] \n" " sub %1, %1, 2 \n" "4: bbit0 %1, 0, 5f \n" "79: stb.ab %2, [%0,1] \n" " sub %1, %1, 1 \n" "5: \n" " .section .fixup, \"ax\" \n" " .align 4 \n" "3: j 5b \n" " .previous \n" " .section __ex_table, \"a\" \n" " .align 4 \n" " .word 75b, 3b \n" " .word 76b, 3b \n" " .word 77b, 3b \n" " .word 78b, 3b \n" " .word 79b, 3b \n" " .previous \n" : "+r"(d_char), "+r"(res) : "i"(0) : "lp_count", "lp_start", "lp_end", "memory"); return res; } static inline long __arc_strncpy_from_user(char *dst, const char __user *src, long count) { long res = count; char val; unsigned int hw_count; if (count == 0) return 0; __asm__ __volatile__( " lp 2f \n" "1: ldb.ab %3, [%2, 1] \n" " breq.d %3, 0, 2f \n" " stb.ab %3, [%1, 1] \n" "2: sub %0, %6, %4 \n" "3: ;nop \n" " .section .fixup, \"ax\" \n" " .align 4 \n" "4: mov %0, %5 \n" " j 3b \n" " .previous \n" " .section __ex_table, \"a\" \n" " .align 4 \n" " .word 1b, 4b \n" " .previous \n" : "=r"(res), "+r"(dst), "+r"(src), "=&r"(val), "=l"(hw_count) : "g"(-EFAULT), "ir"(count), "4"(count) /* this "4" seeds lp_count */ : "memory"); return res; } static inline long __arc_strnlen_user(const char __user *s, long n) { long res, tmp1, cnt; char val; __asm__ __volatile__( " mov %2, %1 \n" "1: ldb.ab %3, [%0, 1] \n" " breq.d %3, 0, 2f \n" " sub.f %2, %2, 1 \n" " bnz 1b \n" " sub %2, %2, 1 \n" "2: sub %0, %1, %2 \n" "3: ;nop \n" " .section .fixup, \"ax\" \n" " .align 4 \n" "4: mov %0, 0 \n" " j 3b \n" " .previous \n" " .section __ex_table, \"a\" \n" " .align 4 \n" " .word 1b, 4b \n" " .previous \n" : "=r"(res), "=r"(tmp1), "=r"(cnt), "=r"(val) : "0"(s), "1"(n) : "memory"); return res; } #ifndef CONFIG_CC_OPTIMIZE_FOR_SIZE #define __copy_from_user(t, f, n) __arc_copy_from_user(t, f, n) #define __copy_to_user(t, f, n) __arc_copy_to_user(t, f, n) #define __clear_user(d, n) __arc_clear_user(d, n) #define __strncpy_from_user(d, s, n) __arc_strncpy_from_user(d, s, n) #define __strnlen_user(s, n) __arc_strnlen_user(s, n) #else extern long arc_copy_from_user_noinline(void *to, const void __user * from, unsigned long n); extern long arc_copy_to_user_noinline(void __user *to, const void *from, unsigned long n); extern unsigned long arc_clear_user_noinline(void __user *to, unsigned long n); extern long arc_strncpy_from_user_noinline (char *dst, const char __user *src, long count); extern long arc_strnlen_user_noinline(const char __user *src, long n); #define __copy_from_user(t, f, n) arc_copy_from_user_noinline(t, f, n) #define __copy_to_user(t, f, n) arc_copy_to_user_noinline(t, f, n) #define __clear_user(d, n) arc_clear_user_noinline(d, n) #define __strncpy_from_user(d, s, n) arc_strncpy_from_user_noinline(d, s, n) #define __strnlen_user(s, n) arc_strnlen_user_noinline(s, n) #endif #include <asm-generic/uaccess.h> extern int fixup_exception(struct pt_regs *regs); #endif