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Diffstat (limited to 'arch/blackfin/include/asm/uaccess.h')
-rw-r--r-- | arch/blackfin/include/asm/uaccess.h | 271 |
1 files changed, 271 insertions, 0 deletions
diff --git a/arch/blackfin/include/asm/uaccess.h b/arch/blackfin/include/asm/uaccess.h new file mode 100644 index 0000000..d928b80 --- /dev/null +++ b/arch/blackfin/include/asm/uaccess.h @@ -0,0 +1,271 @@ +/* Changes made by Lineo Inc. May 2001 + * + * 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> +#ifdef CONFIG_ACCESS_CHECK +# include <asm/bfin-global.h> +#endif + +#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)) + +static inline int is_in_rom(unsigned long addr) +{ + /* + * What we are really trying to do is determine if addr is + * in an allocated kernel memory region. If not then assume + * we cannot free it or otherwise de-allocate it. Ideally + * we could restrict this to really being in a ROM or flash, + * but that would need to be done on a board by board basis, + * not globally. + */ + if ((addr < _ramstart) || (addr >= _ramend)) + return (1); + + /* Default case, not in ROM */ + return (0); +} + +/* + * 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 +#ifdef CONFIG_ACCESS_OK_L1 +extern int _access_ok(unsigned long addr, unsigned long size)__attribute__((l1_text)); +#else +extern int _access_ok(unsigned long addr, unsigned long size); +#endif +#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; +}; + +/* Returns 0 if exception not found and fixup otherwise. */ +extern unsigned long search_exception_table(unsigned long); + +/* + * 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)) *_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 *)_p)+0, ); \ + __put_user_asm(_xh, ((long *)_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 *)(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,p) \ + ({ \ + int _err = 0; \ + typeof(*(p)) *_p = (p); \ + if (!access_ok(VERIFY_READ, _p, sizeof(*(_p)))) { \ + _err = -EFAULT; \ + } \ + else { \ + switch (sizeof(*(_p))) { \ + case 1: \ + __get_user_asm(x, _p, B,(Z)); \ + break; \ + case 2: \ + __get_user_asm(x, _p, W,(Z)); \ + break; \ + case 4: \ + __get_user_asm(x, _p, , ); \ + break; \ + case 8: { \ + unsigned long _xl, _xh; \ + __get_user_asm(_xl, ((unsigned long *)_p)+0, , ); \ + __get_user_asm(_xh, ((unsigned long *)_p)+1, , ); \ + ((unsigned long *)&x)[0] = _xl; \ + ((unsigned long *)&x)[1] = _xh; \ + } break; \ + default: \ + x = 0; \ + printk(KERN_INFO "get_user_bad: %s:%d %s\n", \ + __FILE__, __LINE__, __func__); \ + _err = __get_user_bad(); \ + break; \ + } \ + } \ + _err; \ + }) + +#define __get_user(x,p) get_user(x,p) + +#define __get_user_bad() (bad_user_access_length(), (-EFAULT)) + +#define __get_user_asm(x,p,bhw,option) \ + { \ + unsigned long _tmp; \ + __asm__ ("%0 =" #bhw "[%1]"#option";\n\t" \ + : "=d" (_tmp) \ + : "a" (__ptr(p))); \ + (x) = (__typeof__(*(p))) _tmp; \ + } + +#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 long copy_from_user(void *to, + const void __user * from, unsigned long n) +{ + if (access_ok(VERIFY_READ, from, n)) + memcpy(to, from, n); + else + return n; + return 0; +} + +static inline long copy_to_user(void *to, + const void __user * from, unsigned long n) +{ + if (access_ok(VERIFY_WRITE, to, n)) + memcpy(to, from, n); + else + return n; + return 0; +} + +/* + * Copy a null terminated string from userspace. + */ + +static inline long strncpy_from_user(char *dst, + const char *src, long count) +{ + char *tmp; + if (!access_ok(VERIFY_READ, src, 1)) + return -EFAULT; + strncpy(dst, src, count); + for (tmp = dst; *tmp && count > 0; tmp++, count--) ; + return (tmp - dst); +} + +/* + * Return the size of a string (including the ending 0) + * + * Return 0 on exception, a value greater than N if too long + */ +static inline long strnlen_user(const char *src, long n) +{ + return (strlen(src) + 1); +} + +#define strlen_user(str) strnlen_user(str, 32767) + +/* + * Zero Userspace + */ + +static inline unsigned long __clear_user(void *to, unsigned long n) +{ + memset(to, 0, n); + return 0; +} + +#define clear_user(to, n) __clear_user(to, n) + +#endif /* _BLACKFIN_UACCESS_H */ |