diff options
Diffstat (limited to 'arch/microblaze/include/asm/uaccess.h')
| -rw-r--r-- | arch/microblaze/include/asm/uaccess.h | 30 |
1 files changed, 29 insertions, 1 deletions
diff --git a/arch/microblaze/include/asm/uaccess.h b/arch/microblaze/include/asm/uaccess.h index 371bd6e56d9..a8f794d03c5 100644 --- a/arch/microblaze/include/asm/uaccess.h +++ b/arch/microblaze/include/asm/uaccess.h @@ -22,12 +22,40 @@ #include <asm/mmu.h> #include <asm/page.h> #include <asm/pgtable.h> -#include <asm/segment.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) + + #define __clear_user(addr, n) (memset((void *)(addr), 0, (n)), 0) #ifndef CONFIG_MMU |