| /* |
| * Copyright (C) 2008-2009 Michal Simek <monstr@monstr.eu> |
| * Copyright (C) 2008-2009 PetaLogix |
| * Copyright (C) 2006 Atmark Techno, Inc. |
| * |
| * This file is subject to the terms and conditions of the GNU General Public |
| * License. See the file "COPYING" in the main directory of this archive |
| * for more details. |
| */ |
| |
| #ifndef _ASM_MICROBLAZE_UACCESS_H |
| #define _ASM_MICROBLAZE_UACCESS_H |
| |
| #ifdef __KERNEL__ |
| #ifndef __ASSEMBLY__ |
| |
| #include <linux/kernel.h> |
| #include <linux/errno.h> |
| #include <linux/sched.h> /* RLIMIT_FSIZE */ |
| #include <linux/mm.h> |
| |
| #include <asm/mmu.h> |
| #include <asm/page.h> |
| #include <asm/pgtable.h> |
| #include <linux/string.h> |
| |
| #define VERIFY_READ 0 |
| #define VERIFY_WRITE 1 |
| |
| /* |
| * On Microblaze the fs value is actually the top of the corresponding |
| * address space. |
| * |
| * The fs value determines whether argument validity checking should be |
| * performed or not. If get_fs() == USER_DS, checking is performed, with |
| * get_fs() == KERNEL_DS, checking is bypassed. |
| * |
| * For historical reasons, these macros are grossly misnamed. |
| * |
| * For non-MMU arch like Microblaze, KERNEL_DS and USER_DS is equal. |
| */ |
| # define MAKE_MM_SEG(s) ((mm_segment_t) { (s) }) |
| |
| # ifndef CONFIG_MMU |
| # define KERNEL_DS MAKE_MM_SEG(0) |
| # define USER_DS KERNEL_DS |
| # else |
| # define KERNEL_DS MAKE_MM_SEG(0xFFFFFFFF) |
| # define USER_DS MAKE_MM_SEG(TASK_SIZE - 1) |
| # endif |
| |
| # define get_ds() (KERNEL_DS) |
| # define get_fs() (current_thread_info()->addr_limit) |
| # define set_fs(val) (current_thread_info()->addr_limit = (val)) |
| |
| # define segment_eq(a, b) ((a).seg == (b).seg) |
| |
| /* |
| * The exception table consists of pairs of addresses: the first is the |
| * address of an instruction that is allowed to fault, and the second is |
| * the address at which the program should continue. No registers are |
| * modified, so it is entirely up to the continuation code to figure out |
| * what to do. |
| * |
| * All the routines below use bits of fixup code that are out of line |
| * with the main instruction path. This means when everything is well, |
| * we don't even have to jump over them. Further, they do not intrude |
| * on our cache or tlb entries. |
| */ |
| struct exception_table_entry { |
| unsigned long insn, fixup; |
| }; |
| |
| /* Returns 0 if exception not found and fixup otherwise. */ |
| extern unsigned long search_exception_table(unsigned long); |
| |
| #ifndef CONFIG_MMU |
| |
| /* Check against bounds of physical memory */ |
| static inline int ___range_ok(unsigned long addr, unsigned long size) |
| { |
| return ((addr < memory_start) || |
| ((addr + size) > memory_end)); |
| } |
| |
| #define __range_ok(addr, size) \ |
| ___range_ok((unsigned long)(addr), (unsigned long)(size)) |
| |
| #define access_ok(type, addr, size) (__range_ok((addr), (size)) == 0) |
| |
| #else |
| |
| /* |
| * Address is valid if: |
| * - "addr", "addr + size" and "size" are all below the limit |
| */ |
| #define access_ok(type, addr, size) \ |
| (get_fs().seg >= (((unsigned long)(addr)) | \ |
| (size) | ((unsigned long)(addr) + (size)))) |
| |
| /* || printk("access_ok failed for %s at 0x%08lx (size %d), seg 0x%08x\n", |
| type?"WRITE":"READ",addr,size,get_fs().seg)) */ |
| |
| #endif |
| |
| #ifdef CONFIG_MMU |
| # define __FIXUP_SECTION ".section .fixup,\"ax\"\n" |
| # define __EX_TABLE_SECTION ".section __ex_table,\"a\"\n" |
| #else |
| # define __FIXUP_SECTION ".section .discard,\"ax\"\n" |
| # define __EX_TABLE_SECTION ".section .discard,\"a\"\n" |
| #endif |
| |
| extern unsigned long __copy_tofrom_user(void __user *to, |
| const void __user *from, unsigned long size); |
| |
| /* Return: number of not copied bytes, i.e. 0 if OK or non-zero if fail. */ |
| static inline unsigned long __must_check __clear_user(void __user *to, |
| unsigned long n) |
| { |
| /* normal memset with two words to __ex_table */ |
| __asm__ __volatile__ ( \ |
| "1: sb r0, %1, r0;" \ |
| " addik %0, %0, -1;" \ |
| " bneid %0, 1b;" \ |
| " addik %1, %1, 1;" \ |
| "2: " \ |
| __EX_TABLE_SECTION \ |
| ".word 1b,2b;" \ |
| ".previous;" \ |
| : "=r"(n), "=r"(to) \ |
| : "0"(n), "1"(to) |
| ); |
| return n; |
| } |
| |
| static inline unsigned long __must_check clear_user(void __user *to, |
| unsigned long n) |
| { |
| might_sleep(); |
| if (unlikely(!access_ok(VERIFY_WRITE, to, n))) |
| return n; |
| |
| return __clear_user(to, n); |
| } |
| |
| /* put_user and get_user macros */ |
| extern long __user_bad(void); |
| |
| #define __get_user_asm(insn, __gu_ptr, __gu_val, __gu_err) \ |
| ({ \ |
| __asm__ __volatile__ ( \ |
| "1:" insn " %1, %2, r0;" \ |
| " addk %0, r0, r0;" \ |
| "2: " \ |
| __FIXUP_SECTION \ |
| "3: brid 2b;" \ |
| " addik %0, r0, %3;" \ |
| ".previous;" \ |
| __EX_TABLE_SECTION \ |
| ".word 1b,3b;" \ |
| ".previous;" \ |
| : "=&r"(__gu_err), "=r"(__gu_val) \ |
| : "r"(__gu_ptr), "i"(-EFAULT) \ |
| ); \ |
| }) |
| |
| /** |
| * get_user: - Get a simple variable from user space. |
| * @x: Variable to store result. |
| * @ptr: Source address, in user space. |
| * |
| * Context: User context only. This function may sleep. |
| * |
| * This macro copies a single simple variable from user space to kernel |
| * space. It supports simple types like char and int, but not larger |
| * data types like structures or arrays. |
| * |
| * @ptr must have pointer-to-simple-variable type, and the result of |
| * dereferencing @ptr must be assignable to @x without a cast. |
| * |
| * Returns zero on success, or -EFAULT on error. |
| * On error, the variable @x is set to zero. |
| */ |
| #define get_user(x, ptr) \ |
| __get_user_check((x), (ptr), sizeof(*(ptr))) |
| |
| #define __get_user_check(x, ptr, size) \ |
| ({ \ |
| unsigned long __gu_val = 0; \ |
| const typeof(*(ptr)) __user *__gu_addr = (ptr); \ |
| int __gu_err = 0; \ |
| \ |
| if (access_ok(VERIFY_READ, __gu_addr, size)) { \ |
| switch (size) { \ |
| case 1: \ |
| __get_user_asm("lbu", __gu_addr, __gu_val, \ |
| __gu_err); \ |
| break; \ |
| case 2: \ |
| __get_user_asm("lhu", __gu_addr, __gu_val, \ |
| __gu_err); \ |
| break; \ |
| case 4: \ |
| __get_user_asm("lw", __gu_addr, __gu_val, \ |
| __gu_err); \ |
| break; \ |
| default: \ |
| __gu_err = __user_bad(); \ |
| break; \ |
| } \ |
| } else { \ |
| __gu_err = -EFAULT; \ |
| } \ |
| x = (typeof(*(ptr)))__gu_val; \ |
| __gu_err; \ |
| }) |
| |
| #define __get_user(x, ptr) \ |
| ({ \ |
| unsigned long __gu_val = 0; \ |
| /*unsigned long __gu_ptr = (unsigned long)(ptr);*/ \ |
| long __gu_err; \ |
| switch (sizeof(*(ptr))) { \ |
| case 1: \ |
| __get_user_asm("lbu", (ptr), __gu_val, __gu_err); \ |
| break; \ |
| case 2: \ |
| __get_user_asm("lhu", (ptr), __gu_val, __gu_err); \ |
| break; \ |
| case 4: \ |
| __get_user_asm("lw", (ptr), __gu_val, __gu_err); \ |
| break; \ |
| default: \ |
| /* __gu_val = 0; __gu_err = -EINVAL;*/ __gu_err = __user_bad();\ |
| } \ |
| x = (__typeof__(*(ptr))) __gu_val; \ |
| __gu_err; \ |
| }) |
| |
| |
| #define __put_user_asm(insn, __gu_ptr, __gu_val, __gu_err) \ |
| ({ \ |
| __asm__ __volatile__ ( \ |
| "1:" insn " %1, %2, r0;" \ |
| " addk %0, r0, r0;" \ |
| "2: " \ |
| __FIXUP_SECTION \ |
| "3: brid 2b;" \ |
| " addik %0, r0, %3;" \ |
| ".previous;" \ |
| __EX_TABLE_SECTION \ |
| ".word 1b,3b;" \ |
| ".previous;" \ |
| : "=&r"(__gu_err) \ |
| : "r"(__gu_val), "r"(__gu_ptr), "i"(-EFAULT) \ |
| ); \ |
| }) |
| |
| #define __put_user_asm_8(__gu_ptr, __gu_val, __gu_err) \ |
| ({ \ |
| __asm__ __volatile__ (" lwi %0, %1, 0;" \ |
| "1: swi %0, %2, 0;" \ |
| " lwi %0, %1, 4;" \ |
| "2: swi %0, %2, 4;" \ |
| " addk %0, r0, r0;" \ |
| "3: " \ |
| __FIXUP_SECTION \ |
| "4: brid 3b;" \ |
| " addik %0, r0, %3;" \ |
| ".previous;" \ |
| __EX_TABLE_SECTION \ |
| ".word 1b,4b,2b,4b;" \ |
| ".previous;" \ |
| : "=&r"(__gu_err) \ |
| : "r"(&__gu_val), "r"(__gu_ptr), "i"(-EFAULT) \ |
| ); \ |
| }) |
| |
| /** |
| * put_user: - Write a simple value into user space. |
| * @x: Value to copy to user space. |
| * @ptr: Destination address, in user space. |
| * |
| * Context: User context only. This function may sleep. |
| * |
| * This macro copies a single simple value from kernel space to user |
| * space. It supports simple types like char and int, but not larger |
| * data types like structures or arrays. |
| * |
| * @ptr must have pointer-to-simple-variable type, and @x must be assignable |
| * to the result of dereferencing @ptr. |
| * |
| * Returns zero on success, or -EFAULT on error. |
| */ |
| #define put_user(x, ptr) \ |
| __put_user_check((x), (ptr), sizeof(*(ptr))) |
| |
| #define __put_user_check(x, ptr, size) \ |
| ({ \ |
| typeof(*(ptr)) __pu_val; \ |
| typeof(*(ptr)) __user *__pu_addr = (ptr); \ |
| int __pu_err = 0; \ |
| \ |
| __pu_val = (x); \ |
| if (access_ok(VERIFY_WRITE, __pu_addr, size)) { \ |
| switch (size) { \ |
| case 1: \ |
| __put_user_asm("sb", __pu_addr, __pu_val, \ |
| __pu_err); \ |
| break; \ |
| case 2: \ |
| __put_user_asm("sh", __pu_addr, __pu_val, \ |
| __pu_err); \ |
| break; \ |
| case 4: \ |
| __put_user_asm("sw", __pu_addr, __pu_val, \ |
| __pu_err); \ |
| break; \ |
| case 8: \ |
| __put_user_asm_8(__pu_addr, __pu_val, __pu_err);\ |
| break; \ |
| default: \ |
| __pu_err = __user_bad(); \ |
| break; \ |
| } \ |
| } else { \ |
| __pu_err = -EFAULT; \ |
| } \ |
| __pu_err; \ |
| }) |
| |
| #define __put_user(x, ptr) \ |
| ({ \ |
| __typeof__(*(ptr)) volatile __gu_val = (x); \ |
| long __gu_err = 0; \ |
| switch (sizeof(__gu_val)) { \ |
| case 1: \ |
| __put_user_asm("sb", (ptr), __gu_val, __gu_err); \ |
| break; \ |
| case 2: \ |
| __put_user_asm("sh", (ptr), __gu_val, __gu_err); \ |
| break; \ |
| case 4: \ |
| __put_user_asm("sw", (ptr), __gu_val, __gu_err); \ |
| break; \ |
| case 8: \ |
| __put_user_asm_8((ptr), __gu_val, __gu_err); \ |
| break; \ |
| default: \ |
| /*__gu_err = -EINVAL;*/ __gu_err = __user_bad(); \ |
| } \ |
| __gu_err; \ |
| }) |
| |
| |
| /* copy_to_from_user */ |
| #define __copy_from_user(to, from, n) \ |
| __copy_tofrom_user((__force void __user *)(to), \ |
| (void __user *)(from), (n)) |
| #define __copy_from_user_inatomic(to, from, n) \ |
| __copy_from_user((to), (from), (n)) |
| |
| static inline long copy_from_user(void *to, |
| const void __user *from, unsigned long n) |
| { |
| unsigned long res = n; |
| might_sleep(); |
| if (likely(access_ok(VERIFY_READ, from, n))) |
| res = __copy_from_user(to, from, n); |
| if (unlikely(res)) |
| memset(to + (n - res), 0, res); |
| return res; |
| } |
| |
| #define __copy_to_user(to, from, n) \ |
| __copy_tofrom_user((void __user *)(to), \ |
| (__force const void __user *)(from), (n)) |
| #define __copy_to_user_inatomic(to, from, n) __copy_to_user((to), (from), (n)) |
| |
| static inline long copy_to_user(void __user *to, |
| const void *from, unsigned long n) |
| { |
| might_sleep(); |
| if (access_ok(VERIFY_WRITE, to, n)) |
| return __copy_to_user(to, from, n); |
| return n; |
| } |
| |
| /* |
| * Copy a null terminated string from userspace. |
| */ |
| extern int __strncpy_user(char *to, const char __user *from, int len); |
| |
| #define __strncpy_from_user __strncpy_user |
| |
| static inline long |
| strncpy_from_user(char *dst, const char __user *src, long count) |
| { |
| if (!access_ok(VERIFY_READ, src, 1)) |
| return -EFAULT; |
| return __strncpy_from_user(dst, src, count); |
| } |
| |
| /* |
| * Return the size of a string (including the ending 0) |
| * |
| * Return 0 on exception, a value greater than N if too long |
| */ |
| extern int __strnlen_user(const char __user *sstr, int len); |
| |
| static inline long strnlen_user(const char __user *src, long n) |
| { |
| if (!access_ok(VERIFY_READ, src, 1)) |
| return 0; |
| return __strnlen_user(src, n); |
| } |
| |
| #endif /* __ASSEMBLY__ */ |
| #endif /* __KERNEL__ */ |
| |
| #endif /* _ASM_MICROBLAZE_UACCESS_H */ |