| #ifndef _ASM_IA64_UACCESS_H |
| #define _ASM_IA64_UACCESS_H |
| |
| /* |
| * This file defines various macros to transfer memory areas across |
| * the user/kernel boundary. This needs to be done carefully because |
| * this code is executed in kernel mode and uses user-specified |
| * addresses. Thus, we need to be careful not to let the user to |
| * trick us into accessing kernel memory that would normally be |
| * inaccessible. This code is also fairly performance sensitive, |
| * so we want to spend as little time doing safety checks as |
| * possible. |
| * |
| * To make matters a bit more interesting, these macros sometimes also |
| * called from within the kernel itself, in which case the address |
| * validity check must be skipped. The get_fs() macro tells us what |
| * to do: if get_fs()==USER_DS, checking is performed, if |
| * get_fs()==KERNEL_DS, checking is bypassed. |
| * |
| * Note that even if the memory area specified by the user is in a |
| * valid address range, it is still possible that we'll get a page |
| * fault while accessing it. This is handled by filling out an |
| * exception handler fixup entry for each instruction that has the |
| * potential to fault. When such a fault occurs, the page fault |
| * handler checks to see whether the faulting instruction has a fixup |
| * associated and, if so, sets r8 to -EFAULT and clears r9 to 0 and |
| * then resumes execution at the continuation point. |
| * |
| * Based on <asm-alpha/uaccess.h>. |
| * |
| * Copyright (C) 1998, 1999, 2001-2004 Hewlett-Packard Co |
| * David Mosberger-Tang <davidm@hpl.hp.com> |
| */ |
| |
| #include <linux/compiler.h> |
| #include <linux/errno.h> |
| #include <linux/sched.h> |
| #include <linux/page-flags.h> |
| #include <linux/mm.h> |
| |
| #include <asm/intrinsics.h> |
| #include <asm/pgtable.h> |
| #include <asm/io.h> |
| |
| /* |
| * For historical reasons, the following macros are grossly misnamed: |
| */ |
| #define KERNEL_DS ((mm_segment_t) { ~0UL }) /* cf. access_ok() */ |
| #define USER_DS ((mm_segment_t) { TASK_SIZE-1 }) /* cf. access_ok() */ |
| |
| #define VERIFY_READ 0 |
| #define VERIFY_WRITE 1 |
| |
| #define get_ds() (KERNEL_DS) |
| #define get_fs() (current_thread_info()->addr_limit) |
| #define set_fs(x) (current_thread_info()->addr_limit = (x)) |
| |
| #define segment_eq(a, b) ((a).seg == (b).seg) |
| |
| /* |
| * When accessing user memory, we need to make sure the entire area really is in |
| * user-level space. In order to do this efficiently, we make sure that the page at |
| * address TASK_SIZE is never valid. We also need to make sure that the address doesn't |
| * point inside the virtually mapped linear page table. |
| */ |
| #define __access_ok(addr, size, segment) \ |
| ({ \ |
| __chk_user_ptr(addr); \ |
| (likely((unsigned long) (addr) <= (segment).seg) \ |
| && ((segment).seg == KERNEL_DS.seg \ |
| || likely(REGION_OFFSET((unsigned long) (addr)) < RGN_MAP_LIMIT))); \ |
| }) |
| #define access_ok(type, addr, size) __access_ok((addr), (size), get_fs()) |
| |
| /* |
| * These are the main single-value transfer routines. They automatically |
| * use the right size if we just have the right pointer type. |
| * |
| * Careful to not |
| * (a) re-use the arguments for side effects (sizeof/typeof is ok) |
| * (b) require any knowledge of processes at this stage |
| */ |
| #define put_user(x, ptr) __put_user_check((__typeof__(*(ptr))) (x), (ptr), sizeof(*(ptr)), get_fs()) |
| #define get_user(x, ptr) __get_user_check((x), (ptr), sizeof(*(ptr)), get_fs()) |
| |
| /* |
| * The "__xxx" versions do not do address space checking, useful when |
| * doing multiple accesses to the same area (the programmer has to do the |
| * checks by hand with "access_ok()") |
| */ |
| #define __put_user(x, ptr) __put_user_nocheck((__typeof__(*(ptr))) (x), (ptr), sizeof(*(ptr))) |
| #define __get_user(x, ptr) __get_user_nocheck((x), (ptr), sizeof(*(ptr))) |
| |
| extern long __put_user_unaligned_unknown (void); |
| |
| #define __put_user_unaligned(x, ptr) \ |
| ({ \ |
| long __ret; \ |
| switch (sizeof(*(ptr))) { \ |
| case 1: __ret = __put_user((x), (ptr)); break; \ |
| case 2: __ret = (__put_user((x), (u8 __user *)(ptr))) \ |
| | (__put_user((x) >> 8, ((u8 __user *)(ptr) + 1))); break; \ |
| case 4: __ret = (__put_user((x), (u16 __user *)(ptr))) \ |
| | (__put_user((x) >> 16, ((u16 __user *)(ptr) + 1))); break; \ |
| case 8: __ret = (__put_user((x), (u32 __user *)(ptr))) \ |
| | (__put_user((x) >> 32, ((u32 __user *)(ptr) + 1))); break; \ |
| default: __ret = __put_user_unaligned_unknown(); \ |
| } \ |
| __ret; \ |
| }) |
| |
| extern long __get_user_unaligned_unknown (void); |
| |
| #define __get_user_unaligned(x, ptr) \ |
| ({ \ |
| long __ret; \ |
| switch (sizeof(*(ptr))) { \ |
| case 1: __ret = __get_user((x), (ptr)); break; \ |
| case 2: __ret = (__get_user((x), (u8 __user *)(ptr))) \ |
| | (__get_user((x) >> 8, ((u8 __user *)(ptr) + 1))); break; \ |
| case 4: __ret = (__get_user((x), (u16 __user *)(ptr))) \ |
| | (__get_user((x) >> 16, ((u16 __user *)(ptr) + 1))); break; \ |
| case 8: __ret = (__get_user((x), (u32 __user *)(ptr))) \ |
| | (__get_user((x) >> 32, ((u32 __user *)(ptr) + 1))); break; \ |
| default: __ret = __get_user_unaligned_unknown(); \ |
| } \ |
| __ret; \ |
| }) |
| |
| #ifdef ASM_SUPPORTED |
| struct __large_struct { unsigned long buf[100]; }; |
| # define __m(x) (*(struct __large_struct __user *)(x)) |
| |
| /* We need to declare the __ex_table section before we can use it in .xdata. */ |
| asm (".section \"__ex_table\", \"a\"\n\t.previous"); |
| |
| # define __get_user_size(val, addr, n, err) \ |
| do { \ |
| register long __gu_r8 asm ("r8") = 0; \ |
| register long __gu_r9 asm ("r9"); \ |
| asm ("\n[1:]\tld"#n" %0=%2%P2\t// %0 and %1 get overwritten by exception handler\n" \ |
| "\t.xdata4 \"__ex_table\", 1b-., 1f-.+4\n" \ |
| "[1:]" \ |
| : "=r"(__gu_r9), "=r"(__gu_r8) : "m"(__m(addr)), "1"(__gu_r8)); \ |
| (err) = __gu_r8; \ |
| (val) = __gu_r9; \ |
| } while (0) |
| |
| /* |
| * The "__put_user_size()" macro tells gcc it reads from memory instead of writing it. This |
| * is because they do not write to any memory gcc knows about, so there are no aliasing |
| * issues. |
| */ |
| # define __put_user_size(val, addr, n, err) \ |
| do { \ |
| register long __pu_r8 asm ("r8") = 0; \ |
| asm volatile ("\n[1:]\tst"#n" %1=%r2%P1\t// %0 gets overwritten by exception handler\n" \ |
| "\t.xdata4 \"__ex_table\", 1b-., 1f-.\n" \ |
| "[1:]" \ |
| : "=r"(__pu_r8) : "m"(__m(addr)), "rO"(val), "0"(__pu_r8)); \ |
| (err) = __pu_r8; \ |
| } while (0) |
| |
| #else /* !ASM_SUPPORTED */ |
| # define RELOC_TYPE 2 /* ip-rel */ |
| # define __get_user_size(val, addr, n, err) \ |
| do { \ |
| __ld_user("__ex_table", (unsigned long) addr, n, RELOC_TYPE); \ |
| (err) = ia64_getreg(_IA64_REG_R8); \ |
| (val) = ia64_getreg(_IA64_REG_R9); \ |
| } while (0) |
| # define __put_user_size(val, addr, n, err) \ |
| do { \ |
| __st_user("__ex_table", (unsigned long) addr, n, RELOC_TYPE, (unsigned long) (val)); \ |
| (err) = ia64_getreg(_IA64_REG_R8); \ |
| } while (0) |
| #endif /* !ASM_SUPPORTED */ |
| |
| extern void __get_user_unknown (void); |
| |
| /* |
| * Evaluating arguments X, PTR, SIZE, and SEGMENT may involve subroutine-calls, which |
| * could clobber r8 and r9 (among others). Thus, be careful not to evaluate it while |
| * using r8/r9. |
| */ |
| #define __do_get_user(check, x, ptr, size, segment) \ |
| ({ \ |
| const __typeof__(*(ptr)) __user *__gu_ptr = (ptr); \ |
| __typeof__ (size) __gu_size = (size); \ |
| long __gu_err = -EFAULT; \ |
| unsigned long __gu_val = 0; \ |
| if (!check || __access_ok(__gu_ptr, size, segment)) \ |
| switch (__gu_size) { \ |
| case 1: __get_user_size(__gu_val, __gu_ptr, 1, __gu_err); break; \ |
| case 2: __get_user_size(__gu_val, __gu_ptr, 2, __gu_err); break; \ |
| case 4: __get_user_size(__gu_val, __gu_ptr, 4, __gu_err); break; \ |
| case 8: __get_user_size(__gu_val, __gu_ptr, 8, __gu_err); break; \ |
| default: __get_user_unknown(); break; \ |
| } \ |
| (x) = (__typeof__(*(__gu_ptr))) __gu_val; \ |
| __gu_err; \ |
| }) |
| |
| #define __get_user_nocheck(x, ptr, size) __do_get_user(0, x, ptr, size, KERNEL_DS) |
| #define __get_user_check(x, ptr, size, segment) __do_get_user(1, x, ptr, size, segment) |
| |
| extern void __put_user_unknown (void); |
| |
| /* |
| * Evaluating arguments X, PTR, SIZE, and SEGMENT may involve subroutine-calls, which |
| * could clobber r8 (among others). Thus, be careful not to evaluate them while using r8. |
| */ |
| #define __do_put_user(check, x, ptr, size, segment) \ |
| ({ \ |
| __typeof__ (x) __pu_x = (x); \ |
| __typeof__ (*(ptr)) __user *__pu_ptr = (ptr); \ |
| __typeof__ (size) __pu_size = (size); \ |
| long __pu_err = -EFAULT; \ |
| \ |
| if (!check || __access_ok(__pu_ptr, __pu_size, segment)) \ |
| switch (__pu_size) { \ |
| case 1: __put_user_size(__pu_x, __pu_ptr, 1, __pu_err); break; \ |
| case 2: __put_user_size(__pu_x, __pu_ptr, 2, __pu_err); break; \ |
| case 4: __put_user_size(__pu_x, __pu_ptr, 4, __pu_err); break; \ |
| case 8: __put_user_size(__pu_x, __pu_ptr, 8, __pu_err); break; \ |
| default: __put_user_unknown(); break; \ |
| } \ |
| __pu_err; \ |
| }) |
| |
| #define __put_user_nocheck(x, ptr, size) __do_put_user(0, x, ptr, size, KERNEL_DS) |
| #define __put_user_check(x, ptr, size, segment) __do_put_user(1, x, ptr, size, segment) |
| |
| /* |
| * Complex access routines |
| */ |
| extern unsigned long __must_check __copy_user (void __user *to, const void __user *from, |
| unsigned long count); |
| |
| static inline unsigned long |
| __copy_to_user (void __user *to, const void *from, unsigned long count) |
| { |
| return __copy_user(to, (__force void __user *) from, count); |
| } |
| |
| static inline unsigned long |
| __copy_from_user (void *to, const void __user *from, unsigned long count) |
| { |
| return __copy_user((__force void __user *) to, from, count); |
| } |
| |
| #define __copy_to_user_inatomic __copy_to_user |
| #define __copy_from_user_inatomic __copy_from_user |
| #define copy_to_user(to, from, n) \ |
| ({ \ |
| void __user *__cu_to = (to); \ |
| const void *__cu_from = (from); \ |
| long __cu_len = (n); \ |
| \ |
| if (__access_ok(__cu_to, __cu_len, get_fs())) \ |
| __cu_len = __copy_user(__cu_to, (__force void __user *) __cu_from, __cu_len); \ |
| __cu_len; \ |
| }) |
| |
| #define copy_from_user(to, from, n) \ |
| ({ \ |
| void *__cu_to = (to); \ |
| const void __user *__cu_from = (from); \ |
| long __cu_len = (n); \ |
| \ |
| __chk_user_ptr(__cu_from); \ |
| if (__access_ok(__cu_from, __cu_len, get_fs())) \ |
| __cu_len = __copy_user((__force void __user *) __cu_to, __cu_from, __cu_len); \ |
| __cu_len; \ |
| }) |
| |
| #define __copy_in_user(to, from, size) __copy_user((to), (from), (size)) |
| |
| static inline unsigned long |
| copy_in_user (void __user *to, const void __user *from, unsigned long n) |
| { |
| if (likely(access_ok(VERIFY_READ, from, n) && access_ok(VERIFY_WRITE, to, n))) |
| n = __copy_user(to, from, n); |
| return n; |
| } |
| |
| extern unsigned long __do_clear_user (void __user *, unsigned long); |
| |
| #define __clear_user(to, n) __do_clear_user(to, n) |
| |
| #define clear_user(to, n) \ |
| ({ \ |
| unsigned long __cu_len = (n); \ |
| if (__access_ok(to, __cu_len, get_fs())) \ |
| __cu_len = __do_clear_user(to, __cu_len); \ |
| __cu_len; \ |
| }) |
| |
| |
| /* |
| * Returns: -EFAULT if exception before terminator, N if the entire buffer filled, else |
| * strlen. |
| */ |
| extern long __must_check __strncpy_from_user (char *to, const char __user *from, long to_len); |
| |
| #define strncpy_from_user(to, from, n) \ |
| ({ \ |
| const char __user * __sfu_from = (from); \ |
| long __sfu_ret = -EFAULT; \ |
| if (__access_ok(__sfu_from, 0, get_fs())) \ |
| __sfu_ret = __strncpy_from_user((to), __sfu_from, (n)); \ |
| __sfu_ret; \ |
| }) |
| |
| /* Returns: 0 if bad, string length+1 (memory size) of string if ok */ |
| extern unsigned long __strlen_user (const char __user *); |
| |
| #define strlen_user(str) \ |
| ({ \ |
| const char __user *__su_str = (str); \ |
| unsigned long __su_ret = 0; \ |
| if (__access_ok(__su_str, 0, get_fs())) \ |
| __su_ret = __strlen_user(__su_str); \ |
| __su_ret; \ |
| }) |
| |
| /* |
| * Returns: 0 if exception before NUL or reaching the supplied limit |
| * (N), a value greater than N if the limit would be exceeded, else |
| * strlen. |
| */ |
| extern unsigned long __strnlen_user (const char __user *, long); |
| |
| #define strnlen_user(str, len) \ |
| ({ \ |
| const char __user *__su_str = (str); \ |
| unsigned long __su_ret = 0; \ |
| if (__access_ok(__su_str, 0, get_fs())) \ |
| __su_ret = __strnlen_user(__su_str, len); \ |
| __su_ret; \ |
| }) |
| |
| /* Generic code can't deal with the location-relative format that we use for compactness. */ |
| #define ARCH_HAS_SORT_EXTABLE |
| #define ARCH_HAS_SEARCH_EXTABLE |
| |
| struct exception_table_entry { |
| int addr; /* location-relative address of insn this fixup is for */ |
| int cont; /* location-relative continuation addr.; if bit 2 is set, r9 is set to 0 */ |
| }; |
| |
| extern void ia64_handle_exception (struct pt_regs *regs, const struct exception_table_entry *e); |
| extern const struct exception_table_entry *search_exception_tables (unsigned long addr); |
| |
| static inline int |
| ia64_done_with_exception (struct pt_regs *regs) |
| { |
| const struct exception_table_entry *e; |
| e = search_exception_tables(regs->cr_iip + ia64_psr(regs)->ri); |
| if (e) { |
| ia64_handle_exception(regs, e); |
| return 1; |
| } |
| return 0; |
| } |
| |
| #define ARCH_HAS_TRANSLATE_MEM_PTR 1 |
| static __inline__ void * |
| xlate_dev_mem_ptr(phys_addr_t p) |
| { |
| struct page *page; |
| void *ptr; |
| |
| page = pfn_to_page(p >> PAGE_SHIFT); |
| if (PageUncached(page)) |
| ptr = (void *)p + __IA64_UNCACHED_OFFSET; |
| else |
| ptr = __va(p); |
| |
| return ptr; |
| } |
| |
| /* |
| * Convert a virtual cached kernel memory pointer to an uncached pointer |
| */ |
| static __inline__ void * |
| xlate_dev_kmem_ptr(void *p) |
| { |
| struct page *page; |
| void *ptr; |
| |
| page = virt_to_page((unsigned long)p); |
| if (PageUncached(page)) |
| ptr = (void *)__pa(p) + __IA64_UNCACHED_OFFSET; |
| else |
| ptr = p; |
| |
| return ptr; |
| } |
| |
| #endif /* _ASM_IA64_UACCESS_H */ |