cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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uaccess.c (3044B)

      1/*
      2 * This file is subject to the terms and conditions of the GNU General Public
      3 * License.  See the file "COPYING" in the main directory of this archive
      4 * for more details.
      5 *
      6 * Copyright (C) 2009, Wind River Systems Inc
      7 * Implemented by fredrik.markstrom@gmail.com and ivarholmqvist@gmail.com
      8 */
      9
     10#include <linux/export.h>
     11#include <linux/uaccess.h>
     12
     13asm(".global	raw_copy_from_user\n"
     14	"   .type raw_copy_from_user, @function\n"
     15	"raw_copy_from_user:\n"
     16	"   movi  r2,7\n"
     17	"   mov   r3,r4\n"
     18	"   bge   r2,r6,1f\n"
     19	"   xor   r2,r4,r5\n"
     20	"   andi  r2,r2,3\n"
     21	"   movi  r7,3\n"
     22	"   beq   r2,zero,4f\n"
     23	"1: addi  r6,r6,-1\n"
     24	"   movi  r2,-1\n"
     25	"   beq   r6,r2,3f\n"
     26	"   mov   r7,r2\n"
     27	"2: ldbu  r2,0(r5)\n"
     28	"   addi  r6,r6,-1\n"
     29	"   addi  r5,r5,1\n"
     30	"   stb   r2,0(r3)\n"
     31	"   addi  r3,r3,1\n"
     32	"   bne   r6,r7,2b\n"
     33	"3:\n"
     34	"   addi  r2,r6,1\n"
     35	"   ret\n"
     36	"13:mov   r2,r6\n"
     37	"   ret\n"
     38	"4: andi  r2,r4,1\n"
     39	"   cmpeq r2,r2,zero\n"
     40	"   beq   r2,zero,7f\n"
     41	"5: andi  r2,r3,2\n"
     42	"   beq   r2,zero,6f\n"
     43	"9: ldhu  r2,0(r5)\n"
     44	"   addi  r6,r6,-2\n"
     45	"   addi  r5,r5,2\n"
     46	"   sth   r2,0(r3)\n"
     47	"   addi  r3,r3,2\n"
     48	"6: bge   r7,r6,1b\n"
     49	"10:ldw   r2,0(r5)\n"
     50	"   addi  r6,r6,-4\n"
     51	"   addi  r5,r5,4\n"
     52	"   stw   r2,0(r3)\n"
     53	"   addi  r3,r3,4\n"
     54	"   br    6b\n"
     55	"7: ldbu  r2,0(r5)\n"
     56	"   addi  r6,r6,-1\n"
     57	"   addi  r5,r5,1\n"
     58	"   addi  r3,r4,1\n"
     59	"   stb   r2,0(r4)\n"
     60	"   br    5b\n"
     61	".section __ex_table,\"a\"\n"
     62	".word 2b,3b\n"
     63	".word 9b,13b\n"
     64	".word 10b,13b\n"
     65	".word 7b,13b\n"
     66	".previous\n"
     67	);
     68EXPORT_SYMBOL(raw_copy_from_user);
     69
     70asm(
     71	"   .global raw_copy_to_user\n"
     72	"   .type raw_copy_to_user, @function\n"
     73	"raw_copy_to_user:\n"
     74	"   movi  r2,7\n"
     75	"   mov   r3,r4\n"
     76	"   bge   r2,r6,1f\n"
     77	"   xor   r2,r4,r5\n"
     78	"   andi  r2,r2,3\n"
     79	"   movi  r7,3\n"
     80	"   beq   r2,zero,4f\n"
     81	/* Bail if we try to copy zero bytes  */
     82	"1: addi  r6,r6,-1\n"
     83	"   movi  r2,-1\n"
     84	"   beq   r6,r2,3f\n"
     85	/* Copy byte by byte for small copies and if src^dst != 0 */
     86	"   mov   r7,r2\n"
     87	"2: ldbu  r2,0(r5)\n"
     88	"   addi  r5,r5,1\n"
     89	"9: stb   r2,0(r3)\n"
     90	"   addi  r6,r6,-1\n"
     91	"   addi  r3,r3,1\n"
     92	"   bne   r6,r7,2b\n"
     93	"3: addi  r2,r6,1\n"
     94	"   ret\n"
     95	"13:mov   r2,r6\n"
     96	"   ret\n"
     97	/*  If 'to' is an odd address byte copy */
     98	"4: andi  r2,r4,1\n"
     99	"   cmpeq r2,r2,zero\n"
    100	"   beq   r2,zero,7f\n"
    101	/* If 'to' is not divideable by four copy halfwords */
    102	"5: andi  r2,r3,2\n"
    103	"   beq   r2,zero,6f\n"
    104	"   ldhu  r2,0(r5)\n"
    105	"   addi  r5,r5,2\n"
    106	"10:sth   r2,0(r3)\n"
    107	"   addi  r6,r6,-2\n"
    108	"   addi  r3,r3,2\n"
    109	/* Copy words */
    110	"6: bge   r7,r6,1b\n"
    111	"   ldw   r2,0(r5)\n"
    112	"   addi  r5,r5,4\n"
    113	"11:stw   r2,0(r3)\n"
    114	"   addi  r6,r6,-4\n"
    115	"   addi  r3,r3,4\n"
    116	"   br    6b\n"
    117	/* Copy remaining bytes */
    118	"7: ldbu  r2,0(r5)\n"
    119	"   addi  r5,r5,1\n"
    120	"   addi  r3,r4,1\n"
    121	"12: stb  r2,0(r4)\n"
    122	"   addi  r6,r6,-1\n"
    123	"   br    5b\n"
    124	".section __ex_table,\"a\"\n"
    125	".word 9b,3b\n"
    126	".word 10b,13b\n"
    127	".word 11b,13b\n"
    128	".word 12b,13b\n"
    129	".previous\n");
    130EXPORT_SYMBOL(raw_copy_to_user);