diff options
author | Ralf Baechle <ralf@linux-mips.org> | 2001-01-10 05:27:25 +0000 |
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committer | Ralf Baechle <ralf@linux-mips.org> | 2001-01-10 05:27:25 +0000 |
commit | c9c06167e7933d93a6e396174c68abf242294abb (patch) | |
tree | d9a8bb30663e9a3405a1ef37ffb62bc14b9f019f /include/asm-parisc/uaccess.h | |
parent | f79e8cc3c34e4192a3e5ef4cc9c6542fdef703c0 (diff) |
Merge with Linux 2.4.0-test12.
Diffstat (limited to 'include/asm-parisc/uaccess.h')
-rw-r--r-- | include/asm-parisc/uaccess.h | 189 |
1 files changed, 189 insertions, 0 deletions
diff --git a/include/asm-parisc/uaccess.h b/include/asm-parisc/uaccess.h new file mode 100644 index 000000000..70e834f12 --- /dev/null +++ b/include/asm-parisc/uaccess.h @@ -0,0 +1,189 @@ +#ifndef __PARISC_UACCESS_H +#define __PARISC_UACCESS_H + +/* + * User space memory access functions + */ +#include <linux/sched.h> +#include <asm/page.h> +#include <asm/system.h> +#include <asm/cache.h> + +#define VERIFY_READ 0 +#define VERIFY_WRITE 1 + +#define KERNEL_DS ((mm_segment_t){0}) +#define USER_DS ((mm_segment_t){1}) + +#define segment_eq(a,b) ((a).seg == (b).seg) + +#define get_ds() (KERNEL_DS) +#define get_fs() (current->addr_limit) +#define set_fs(x) (current->addr_limit = (x)) + +/* + * Note that since kernel addresses are in a separate address space on + * parisc, we don't need to do anything for access_ok() or verify_area(). + * We just let the page fault handler do the right thing. This also means + * that put_user is the same as __put_user, etc. + */ + +#define access_ok(type,addr,size) (1) +#define verify_area(type,addr,size) (0) + +#define put_user __put_user +#define get_user __get_user + +/* + * The exception table contains two values: the first is an address + * for an instruction that is allowed to fault, and the second is + * the number of bytes to skip if a fault occurs. We also support in + * two bit flags: 0x2 tells the exception handler to clear register + * r9 and 0x1 tells the exception handler to put -EFAULT in r8. + * This allows us to handle the simple cases for put_user and + * get_user without having to have .fixup sections. + */ + +struct exception_table_entry { + unsigned long addr; /* address of insn that is allowed to fault. */ + int skip; /* pcoq skip | r9 clear flag | r8 -EFAULT flag */ +}; + +extern const struct exception_table_entry + *search_exception_table(unsigned long addr); + +#define __get_user(x,ptr) \ +({ \ + register long __gu_err __asm__ ("r8") = 0; \ + register long __gu_val __asm__ ("r9") = 0; \ + \ + if (segment_eq(get_fs(),KERNEL_DS)) { \ + switch (sizeof(*(ptr))) { \ + case 1: __get_kernel_asm("ldb",ptr); break; \ + case 2: __get_kernel_asm("ldh",ptr); break; \ + case 4: __get_kernel_asm("ldw",ptr); break; \ + case 8: __get_kernel_asm("ldd",ptr); break; \ + default: BUG(); break; \ + } \ + } \ + else { \ + switch (sizeof(*(ptr))) { \ + case 1: __get_user_asm("ldb",ptr); break; \ + case 2: __get_user_asm("ldh",ptr); break; \ + case 4: __get_user_asm("ldw",ptr); break; \ + case 8: __get_user_asm("ldd",ptr); break; \ + default: BUG(); break; \ + } \ + } \ + \ + (x) = (__typeof__(*(ptr))) __gu_val; \ + __gu_err; \ +}) + +#define __get_kernel_asm(ldx,ptr) \ + __asm__("\n1:\t" ldx "\t0(%2),%0\n" \ + "2:\n" \ + "\t.section __ex_table,\"a\"\n" \ + "\t.word\t1b\n" \ + "\t.word\t(2b-1b)+3\n" \ + "\t.previous" \ + : "=r"(__gu_val), "=r"(__gu_err) \ + : "r"(ptr), "1"(__gu_err)); + +#define __get_user_asm(ldx,ptr) \ + __asm__("\n1:\t" ldx "\t0(%%sr3,%2),%0\n" \ + "2:\n" \ + "\t.section __ex_table,\"a\"\n" \ + "\t.word\t1b\n" \ + "\t.word\t(2b-1b)+3\n" \ + "\t.previous" \ + : "=r"(__gu_val), "=r"(__gu_err) \ + : "r"(ptr), "1"(__gu_err)); + + +#define __put_user(x,ptr) \ +({ \ + register long __pu_err __asm__ ("r8") = 0; \ + \ + if (segment_eq(get_fs(),KERNEL_DS)) { \ + switch (sizeof(*(ptr))) { \ + case 1: __put_kernel_asm("stb",x,ptr); break; \ + case 2: __put_kernel_asm("sth",x,ptr); break; \ + case 4: __put_kernel_asm("stw",x,ptr); break; \ + case 8: __put_kernel_asm("std",x,ptr); break; \ + default: BUG(); break; \ + } \ + } \ + else { \ + switch (sizeof(*(ptr))) { \ + case 1: __put_user_asm("stb",x,ptr); break; \ + case 2: __put_user_asm("sth",x,ptr); break; \ + case 4: __put_user_asm("stw",x,ptr); break; \ + case 8: __put_user_asm("std",x,ptr); break; \ + default: BUG(); break; \ + } \ + } \ + \ + __pu_err; \ +}) + +/* + * The "__put_user/kernel_asm()" macros tell gcc they read from memory + * instead of writing. This is because they do not write to any memory + * gcc knows about, so there are no aliasing issues. + */ + +#define __put_kernel_asm(stx,x,ptr) \ + __asm__ __volatile__ ( \ + "\n1:\t" stx "\t%2,0(%1)\n" \ + "2:\n" \ + "\t.section __ex_table,\"a\"\n" \ + "\t.word\t1b\n" \ + "\t.word\t(2b-1b)+1\n" \ + "\t.previous" \ + : "=r"(__pu_err) \ + : "r"(ptr), "r"(x), "0"(__pu_err)) + +#define __put_user_asm(stx,x,ptr) \ + __asm__ __volatile__ ( \ + "\n1:\t" stx "\t%2,0(%%sr3,%1)\n" \ + "2:\n" \ + "\t.section __ex_table,\"a\"\n" \ + "\t.word\t1b\n" \ + "\t.word\t(2b-1b)+1\n" \ + "\t.previous" \ + : "=r"(__pu_err) \ + : "r"(ptr), "r"(x), "0"(__pu_err)) + + +/* + * Complex access routines -- external declarations + */ + +extern unsigned long lcopy_to_user(void *, const void *, unsigned long); +extern unsigned long lcopy_from_user(void *, const void *, unsigned long); +extern long lstrncpy_from_user(char *, const char *, long); +extern unsigned lclear_user(void *,unsigned long); +extern long lstrnlen_user(const char *,long); + +/* + * Complex access routines -- macros + */ + +#define strncpy_from_user lstrncpy_from_user +#define strnlen_user lstrnlen_user +#define strlen_user(str) lstrnlen_user(str, 0x7fffffffL) +#define clear_user lclear_user + +#define copy_from_user lcopy_from_user +#define __copy_from_user lcopy_from_user +#define copy_to_user lcopy_to_user +#define __copy_to_user lcopy_to_user + +#define copy_to_user_ret(to,from,n,retval) \ + ({ if (lcopy_to_user(to,from,n)) return retval; }) + +#define copy_from_user_ret(to,from,n,retval) \ + ({ if (lcopy_from_user(to,from,n)) return retval; }) + +#endif /* __PARISC_UACCESS_H */ |