linux_dsm_epyc7002/include/asm-parisc/uaccess.h
Carlos O'Donell 3fd3a74f45 [PARISC] Use FIXUP_BRANCH_CLOBBER to asm clobber list
Joel Soete noticed correctly that the fixup's clobbers must be listed
as the ASM clobbers. FIXUP_BRANCH in unaligned.c has a new macro which
lists all the clobbers in the fixup, we use this throughout the file
to simplify the process of listing clobbers in the future.

A missing "r1" clobber is added to our uaccess.h for the 64-bit
__put_kernel_asm. Interestingly this is a pretty serious bug since gcc
generates pretty good use of r1 as a temporary and the uses of
__put_kernel_asm are varied and dangerous if r1 is scratched during
an invalid write.

Signed-off-by: Joel Soete <soete.joel@tiscali.be>
Signed-off-by: Carlos O'Donell <carlos@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2006-06-27 23:28:33 +00:00

289 lines
10 KiB
C

#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>
#include <asm-generic/uaccess.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_thread_info()->addr_limit)
#define set_fs(x) (current_thread_info()->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().
* We just let the page fault handler do the right thing. This also means
* that put_user is the same as __put_user, etc.
*/
extern int __get_kernel_bad(void);
extern int __get_user_bad(void);
extern int __put_kernel_bad(void);
extern int __put_user_bad(void);
static inline long access_ok(int type, const void __user * addr,
unsigned long size)
{
return 1;
}
#define put_user __put_user
#define get_user __get_user
#if BITS_PER_LONG == 32
#define LDD_KERNEL(ptr) __get_kernel_bad();
#define LDD_USER(ptr) __get_user_bad();
#define STD_KERNEL(x, ptr) __put_kernel_asm64(x,ptr)
#define STD_USER(x, ptr) __put_user_asm64(x,ptr)
#else
#define LDD_KERNEL(ptr) __get_kernel_asm("ldd",ptr)
#define LDD_USER(ptr) __get_user_asm("ldd",ptr)
#define STD_KERNEL(x, ptr) __put_kernel_asm("std",x,ptr)
#define STD_USER(x, ptr) __put_user_asm("std",x,ptr)
#endif
/*
* The exception table contains two values: the first is an address
* for an instruction that is allowed to fault, and the second is
* the address to the fixup routine.
*/
struct exception_table_entry {
unsigned long insn; /* address of insn that is allowed to fault. */
long fixup; /* fixup routine */
};
/*
* The page fault handler stores, in a per-cpu area, the following information
* if a fixup routine is available.
*/
struct exception_data {
unsigned long fault_ip;
unsigned long fault_space;
unsigned long fault_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: LDD_KERNEL(ptr); break; \
default: __get_kernel_bad(); 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: LDD_USER(ptr); break; \
default: __get_user_bad(); break; \
} \
} \
\
(x) = (__typeof__(*(ptr))) __gu_val; \
__gu_err; \
})
#ifdef __LP64__
#define __get_kernel_asm(ldx,ptr) \
__asm__("\n1:\t" ldx "\t0(%2),%0\n" \
"\t.section __ex_table,\"aw\"\n" \
"\t.dword\t1b,fixup_get_user_skip_1\n" \
"\t.previous" \
: "=r"(__gu_val), "=r"(__gu_err) \
: "r"(ptr), "1"(__gu_err) \
: "r1");
#define __get_user_asm(ldx,ptr) \
__asm__("\n1:\t" ldx "\t0(%%sr3,%2),%0\n" \
"\t.section __ex_table,\"aw\"\n" \
"\t.dword\t1b,fixup_get_user_skip_1\n" \
"\t.previous" \
: "=r"(__gu_val), "=r"(__gu_err) \
: "r"(ptr), "1"(__gu_err) \
: "r1");
#else
#define __get_kernel_asm(ldx,ptr) \
__asm__("\n1:\t" ldx "\t0(%2),%0\n" \
"\t.section __ex_table,\"aw\"\n" \
"\t.word\t1b,fixup_get_user_skip_1\n" \
"\t.previous" \
: "=r"(__gu_val), "=r"(__gu_err) \
: "r"(ptr), "1"(__gu_err) \
: "r1");
#define __get_user_asm(ldx,ptr) \
__asm__("\n1:\t" ldx "\t0(%%sr3,%2),%0\n" \
"\t.section __ex_table,\"aw\"\n" \
"\t.word\t1b,fixup_get_user_skip_1\n" \
"\t.previous" \
: "=r"(__gu_val), "=r"(__gu_err) \
: "r"(ptr), "1"(__gu_err) \
: "r1");
#endif /* !__LP64__ */
#define __put_user(x,ptr) \
({ \
register long __pu_err __asm__ ("r8") = 0; \
__typeof__(*(ptr)) __x = (__typeof__(*(ptr)))(x); \
\
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: STD_KERNEL(__x,ptr); break; \
default: __put_kernel_bad(); 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: STD_USER(__x,ptr); break; \
default: __put_user_bad(); 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. These macros must
* also be aware that "fixup_put_user_skip_[12]" are executed in the
* context of the fault, and any registers used there must be listed
* as clobbers. In this case only "r1" is used by the current routines.
* r8/r9 are already listed as err/val.
*/
#ifdef __LP64__
#define __put_kernel_asm(stx,x,ptr) \
__asm__ __volatile__ ( \
"\n1:\t" stx "\t%2,0(%1)\n" \
"\t.section __ex_table,\"aw\"\n" \
"\t.dword\t1b,fixup_put_user_skip_1\n" \
"\t.previous" \
: "=r"(__pu_err) \
: "r"(ptr), "r"(x), "0"(__pu_err) \
: "r1")
#define __put_user_asm(stx,x,ptr) \
__asm__ __volatile__ ( \
"\n1:\t" stx "\t%2,0(%%sr3,%1)\n" \
"\t.section __ex_table,\"aw\"\n" \
"\t.dword\t1b,fixup_put_user_skip_1\n" \
"\t.previous" \
: "=r"(__pu_err) \
: "r"(ptr), "r"(x), "0"(__pu_err) \
: "r1")
#else
#define __put_kernel_asm(stx,x,ptr) \
__asm__ __volatile__ ( \
"\n1:\t" stx "\t%2,0(%1)\n" \
"\t.section __ex_table,\"aw\"\n" \
"\t.word\t1b,fixup_put_user_skip_1\n" \
"\t.previous" \
: "=r"(__pu_err) \
: "r"(ptr), "r"(x), "0"(__pu_err) \
: "r1")
#define __put_user_asm(stx,x,ptr) \
__asm__ __volatile__ ( \
"\n1:\t" stx "\t%2,0(%%sr3,%1)\n" \
"\t.section __ex_table,\"aw\"\n" \
"\t.word\t1b,fixup_put_user_skip_1\n" \
"\t.previous" \
: "=r"(__pu_err) \
: "r"(ptr), "r"(x), "0"(__pu_err) \
: "r1")
#define __put_kernel_asm64(__val,ptr) do { \
u64 __val64 = (u64)(__val); \
u32 hi = (__val64) >> 32; \
u32 lo = (__val64) & 0xffffffff; \
__asm__ __volatile__ ( \
"\n1:\tstw %2,0(%1)\n" \
"\n2:\tstw %3,4(%1)\n" \
"\t.section __ex_table,\"aw\"\n" \
"\t.word\t1b,fixup_put_user_skip_2\n" \
"\t.word\t2b,fixup_put_user_skip_1\n" \
"\t.previous" \
: "=r"(__pu_err) \
: "r"(ptr), "r"(hi), "r"(lo), "0"(__pu_err) \
: "r1"); \
} while (0)
#define __put_user_asm64(__val,ptr) do { \
u64 __val64 = (u64)__val; \
u32 hi = (__val64) >> 32; \
u32 lo = (__val64) & 0xffffffff; \
__asm__ __volatile__ ( \
"\n1:\tstw %2,0(%%sr3,%1)\n" \
"\n2:\tstw %3,4(%%sr3,%1)\n" \
"\t.section __ex_table,\"aw\"\n" \
"\t.word\t1b,fixup_get_user_skip_2\n" \
"\t.word\t2b,fixup_get_user_skip_1\n" \
"\t.previous" \
: "=r"(__pu_err) \
: "r"(ptr), "r"(hi), "r"(lo), "0"(__pu_err) \
: "r1"); \
} while (0)
#endif /* !__LP64__ */
/*
* Complex access routines -- external declarations
*/
extern unsigned long lcopy_to_user(void __user *, const void *, unsigned long);
extern unsigned long lcopy_from_user(void *, const void __user *, unsigned long);
extern unsigned long lcopy_in_user(void __user *, const void __user *, unsigned long);
extern long lstrncpy_from_user(char *, const char __user *, long);
extern unsigned lclear_user(void __user *,unsigned long);
extern long lstrnlen_user(const char __user *,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 __clear_user lclear_user
unsigned long copy_to_user(void __user *dst, const void *src, unsigned long len);
#define __copy_to_user copy_to_user
unsigned long copy_from_user(void *dst, const void __user *src, unsigned long len);
#define __copy_from_user copy_from_user
unsigned long copy_in_user(void __user *dst, const void __user *src, unsigned long len);
#define __copy_in_user copy_in_user
#define __copy_to_user_inatomic __copy_to_user
#define __copy_from_user_inatomic __copy_from_user
#endif /* __PARISC_UACCESS_H */