| /* |
| * Copyright 2004-2009 Analog Devices Inc. |
| * |
| * Licensed under the GPL-2 or later. |
| * |
| * Based on: include/asm-m68knommu/uaccess.h |
| */ |
| |
| #ifndef __BLACKFIN_UACCESS_H |
| #define __BLACKFIN_UACCESS_H |
| |
| /* |
| * User space memory access functions |
| */ |
| #include <linux/sched.h> |
| #include <linux/mm.h> |
| #include <linux/string.h> |
| |
| #include <asm/segment.h> |
| #include <asm/sections.h> |
| |
| #define get_ds() (KERNEL_DS) |
| #define get_fs() (current_thread_info()->addr_limit) |
| |
| static inline void set_fs(mm_segment_t fs) |
| { |
| current_thread_info()->addr_limit = fs; |
| } |
| |
| #define segment_eq(a,b) ((a) == (b)) |
| |
| #define VERIFY_READ 0 |
| #define VERIFY_WRITE 1 |
| |
| #define access_ok(type, addr, size) _access_ok((unsigned long)(addr), (size)) |
| |
| /* |
| * 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. |
| */ |
| |
| #ifndef CONFIG_ACCESS_CHECK |
| static inline int _access_ok(unsigned long addr, unsigned long size) { return 1; } |
| #else |
| extern int _access_ok(unsigned long addr, unsigned long size); |
| #endif |
| |
| /* |
| * 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; |
| }; |
| |
| /* |
| * These are the main single-value transfer routines. They automatically |
| * use the right size if we just have the right pointer type. |
| */ |
| |
| #define put_user(x,p) \ |
| ({ \ |
| int _err = 0; \ |
| typeof(*(p)) _x = (x); \ |
| typeof(*(p)) __user *_p = (p); \ |
| if (!access_ok(VERIFY_WRITE, _p, sizeof(*(_p)))) {\ |
| _err = -EFAULT; \ |
| } \ |
| else { \ |
| switch (sizeof (*(_p))) { \ |
| case 1: \ |
| __put_user_asm(_x, _p, B); \ |
| break; \ |
| case 2: \ |
| __put_user_asm(_x, _p, W); \ |
| break; \ |
| case 4: \ |
| __put_user_asm(_x, _p, ); \ |
| break; \ |
| case 8: { \ |
| long _xl, _xh; \ |
| _xl = ((long *)&_x)[0]; \ |
| _xh = ((long *)&_x)[1]; \ |
| __put_user_asm(_xl, ((long __user *)_p)+0, ); \ |
| __put_user_asm(_xh, ((long __user *)_p)+1, ); \ |
| } break; \ |
| default: \ |
| _err = __put_user_bad(); \ |
| break; \ |
| } \ |
| } \ |
| _err; \ |
| }) |
| |
| #define __put_user(x,p) put_user(x,p) |
| static inline int bad_user_access_length(void) |
| { |
| panic("bad_user_access_length"); |
| return -1; |
| } |
| |
| #define __put_user_bad() (printk(KERN_INFO "put_user_bad %s:%d %s\n",\ |
| __FILE__, __LINE__, __func__),\ |
| bad_user_access_length(), (-EFAULT)) |
| |
| /* |
| * Tell gcc we read from memory instead of writing: this is because |
| * we do not write to any memory gcc knows about, so there are no |
| * aliasing issues. |
| */ |
| |
| #define __ptr(x) ((unsigned long __force *)(x)) |
| |
| #define __put_user_asm(x,p,bhw) \ |
| __asm__ (#bhw"[%1] = %0;\n\t" \ |
| : /* no outputs */ \ |
| :"d" (x),"a" (__ptr(p)) : "memory") |
| |
| #define get_user(x, ptr) \ |
| ({ \ |
| int _err = 0; \ |
| unsigned long _val = 0; \ |
| const typeof(*(ptr)) __user *_p = (ptr); \ |
| const size_t ptr_size = sizeof(*(_p)); \ |
| if (likely(access_ok(VERIFY_READ, _p, ptr_size))) { \ |
| BUILD_BUG_ON(ptr_size >= 8); \ |
| switch (ptr_size) { \ |
| case 1: \ |
| __get_user_asm(_val, _p, B,(Z)); \ |
| break; \ |
| case 2: \ |
| __get_user_asm(_val, _p, W,(Z)); \ |
| break; \ |
| case 4: \ |
| __get_user_asm(_val, _p, , ); \ |
| break; \ |
| } \ |
| } else \ |
| _err = -EFAULT; \ |
| x = (typeof(*(ptr)))_val; \ |
| _err; \ |
| }) |
| |
| #define __get_user(x,p) get_user(x,p) |
| |
| #define __get_user_bad() (bad_user_access_length(), (-EFAULT)) |
| |
| #define __get_user_asm(x, ptr, bhw, option) \ |
| ({ \ |
| __asm__ __volatile__ ( \ |
| "%0 =" #bhw "[%1]" #option ";" \ |
| : "=d" (x) \ |
| : "a" (__ptr(ptr))); \ |
| }) |
| |
| #define __copy_from_user(to, from, n) copy_from_user(to, from, n) |
| #define __copy_to_user(to, from, n) copy_to_user(to, from, n) |
| #define __copy_to_user_inatomic __copy_to_user |
| #define __copy_from_user_inatomic __copy_from_user |
| |
| #define copy_to_user_ret(to,from,n,retval) ({ if (copy_to_user(to,from,n))\ |
| return retval; }) |
| |
| #define copy_from_user_ret(to,from,n,retval) ({ if (copy_from_user(to,from,n))\ |
| return retval; }) |
| |
| static inline unsigned long __must_check |
| copy_from_user(void *to, const void __user *from, unsigned long n) |
| { |
| if (access_ok(VERIFY_READ, from, n)) |
| memcpy(to, (const void __force *)from, n); |
| else |
| return n; |
| return 0; |
| } |
| |
| static inline unsigned long __must_check |
| copy_to_user(void __user *to, const void *from, unsigned long n) |
| { |
| if (access_ok(VERIFY_WRITE, to, n)) |
| memcpy((void __force *)to, from, n); |
| else |
| return n; |
| return 0; |
| } |
| |
| /* |
| * Copy a null terminated string from userspace. |
| */ |
| |
| static inline long __must_check |
| strncpy_from_user(char *dst, const char __user *src, long count) |
| { |
| char *tmp; |
| if (!access_ok(VERIFY_READ, src, 1)) |
| return -EFAULT; |
| strncpy(dst, (const char __force *)src, count); |
| for (tmp = dst; *tmp && count > 0; tmp++, count--) ; |
| return (tmp - dst); |
| } |
| |
| /* |
| * Get the size of a string in user space. |
| * src: The string to measure |
| * n: The maximum valid length |
| * |
| * Get the size of a NUL-terminated string in user space. |
| * |
| * Returns the size of the string INCLUDING the terminating NUL. |
| * On exception, returns 0. |
| * If the string is too long, returns a value greater than n. |
| */ |
| static inline long __must_check strnlen_user(const char __user *src, long n) |
| { |
| if (!access_ok(VERIFY_READ, src, 1)) |
| return 0; |
| return strnlen((const char __force *)src, n) + 1; |
| } |
| |
| static inline long __must_check strlen_user(const char __user *src) |
| { |
| if (!access_ok(VERIFY_READ, src, 1)) |
| return 0; |
| return strlen((const char __force *)src) + 1; |
| } |
| |
| /* |
| * Zero Userspace |
| */ |
| |
| static inline unsigned long __must_check |
| __clear_user(void __user *to, unsigned long n) |
| { |
| if (!access_ok(VERIFY_WRITE, to, n)) |
| return n; |
| memset((void __force *)to, 0, n); |
| return 0; |
| } |
| |
| #define clear_user(to, n) __clear_user(to, n) |
| |
| /* How to interpret these return values: |
| * CORE: can be accessed by core load or dma memcpy |
| * CORE_ONLY: can only be accessed by core load |
| * DMA: can only be accessed by dma memcpy |
| * IDMA: can only be accessed by interprocessor dma memcpy (BF561) |
| * ITEST: can be accessed by isram memcpy or dma memcpy |
| */ |
| enum { |
| BFIN_MEM_ACCESS_CORE = 0, |
| BFIN_MEM_ACCESS_CORE_ONLY, |
| BFIN_MEM_ACCESS_DMA, |
| BFIN_MEM_ACCESS_IDMA, |
| BFIN_MEM_ACCESS_ITEST, |
| }; |
| /** |
| * bfin_mem_access_type() - what kind of memory access is required |
| * @addr: the address to check |
| * @size: number of bytes needed |
| * @return: <0 is error, >=0 is BFIN_MEM_ACCESS_xxx enum (see above) |
| */ |
| int bfin_mem_access_type(unsigned long addr, unsigned long size); |
| |
| #endif /* _BLACKFIN_UACCESS_H */ |