1 /* 2 * Copyright (c) by Jaroslav Kysela <perex@suse.cz> 3 * 4 * Misc memory accessors 5 * 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License as published by 9 * the Free Software Foundation; either version 2 of the License, or 10 * (at your option) any later version. 11 * 12 * This program is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 * GNU General Public License for more details. 16 * 17 * You should have received a copy of the GNU General Public License 18 * along with this program; if not, write to the Free Software 19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 20 * 21 */ 22 23 #include <linux/config.h> 24 #include <asm/io.h> 25 #include <asm/uaccess.h> 26 27 /** 28 * copy_to_user_fromio - copy data from mmio-space to user-space 29 * @dst: the destination pointer on user-space 30 * @src: the source pointer on mmio 31 * @count: the data size to copy in bytes 32 * 33 * Copies the data from mmio-space to user-space. 34 * 35 * Returns zero if successful, or non-zero on failure. 36 */ 37 int copy_to_user_fromio(void __user *dst, const volatile void __iomem *src, size_t count) 38 { 39 #if defined(__i386__) || defined(CONFIG_SPARC32) 40 return copy_to_user(dst, (const void __force*)src, count) ? -EFAULT : 0; 41 #else 42 char buf[256]; 43 while (count) { 44 size_t c = count; 45 if (c > sizeof(buf)) 46 c = sizeof(buf); 47 memcpy_fromio(buf, (void __iomem *)src, c); 48 if (copy_to_user(dst, buf, c)) 49 return -EFAULT; 50 count -= c; 51 dst += c; 52 src += c; 53 } 54 return 0; 55 #endif 56 } 57 58 /** 59 * copy_from_user_toio - copy data from user-space to mmio-space 60 * @dst: the destination pointer on mmio-space 61 * @src: the source pointer on user-space 62 * @count: the data size to copy in bytes 63 * 64 * Copies the data from user-space to mmio-space. 65 * 66 * Returns zero if successful, or non-zero on failure. 67 */ 68 int copy_from_user_toio(volatile void __iomem *dst, const void __user *src, size_t count) 69 { 70 #if defined(__i386__) || defined(CONFIG_SPARC32) 71 return copy_from_user((void __force *)dst, src, count) ? -EFAULT : 0; 72 #else 73 char buf[256]; 74 while (count) { 75 size_t c = count; 76 if (c > sizeof(buf)) 77 c = sizeof(buf); 78 if (copy_from_user(buf, src, c)) 79 return -EFAULT; 80 memcpy_toio(dst, buf, c); 81 count -= c; 82 dst += c; 83 src += c; 84 } 85 return 0; 86 #endif 87 } 88