diff options
| author | Heiko Carstens <hca@linux.ibm.com> | 2020-09-14 13:42:25 +0200 |
|---|---|---|
| committer | Vasily Gorbik <gor@linux.ibm.com> | 2020-09-17 14:11:03 +0200 |
| commit | 110a6dbb2eca6b10bf60c61a51063d7fe1e55078 (patch) | |
| tree | 2f2468f348579c3c518baf6ff4b567f1d45a232a /arch/s390/include | |
| parent | fc3f61e1bcd5f88bfb7241bf509a3f63bab49ea8 (diff) | |
s390/uaccess: add HAVE_GET_KERNEL_NOFAULT support
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Diffstat (limited to 'arch/s390/include')
| -rw-r--r-- | arch/s390/include/asm/uaccess.h | 111 |
1 files changed, 111 insertions, 0 deletions
diff --git a/arch/s390/include/asm/uaccess.h b/arch/s390/include/asm/uaccess.h index f09444d6aeab..23c85801cf04 100644 --- a/arch/s390/include/asm/uaccess.h +++ b/arch/s390/include/asm/uaccess.h @@ -278,4 +278,115 @@ static inline unsigned long __must_check clear_user(void __user *to, unsigned lo int copy_to_user_real(void __user *dest, void *src, unsigned long count); void *s390_kernel_write(void *dst, const void *src, size_t size); +#define HAVE_GET_KERNEL_NOFAULT + +int __noreturn __put_kernel_bad(void); + +#define __put_kernel_asm(val, to, insn) \ +({ \ + int __rc; \ + \ + asm volatile( \ + "0: " insn " %2,%1\n" \ + "1: xr %0,%0\n" \ + "2:\n" \ + ".pushsection .fixup, \"ax\"\n" \ + "3: lhi %0,%3\n" \ + " jg 2b\n" \ + ".popsection\n" \ + EX_TABLE(0b,3b) EX_TABLE(1b,3b) \ + : "=d" (__rc), "+Q" (*(to)) \ + : "d" (val), "K" (-EFAULT) \ + : "cc"); \ + __rc; \ +}) + +#define __put_kernel_nofault(dst, src, type, err_label) \ +do { \ + u64 __x = (u64)(*((type *)(src))); \ + int __pk_err; \ + \ + switch (sizeof(type)) { \ + case 1: \ + __pk_err = __put_kernel_asm(__x, (type *)(dst), "stc"); \ + break; \ + case 2: \ + __pk_err = __put_kernel_asm(__x, (type *)(dst), "sth"); \ + break; \ + case 4: \ + __pk_err = __put_kernel_asm(__x, (type *)(dst), "st"); \ + break; \ + case 8: \ + __pk_err = __put_kernel_asm(__x, (type *)(dst), "stg"); \ + break; \ + default: \ + __pk_err = __put_kernel_bad(); \ + break; \ + } \ + if (unlikely(__pk_err)) \ + goto err_label; \ +} while (0) + +int __noreturn __get_kernel_bad(void); + +#define __get_kernel_asm(val, from, insn) \ +({ \ + int __rc; \ + \ + asm volatile( \ + "0: " insn " %1,%2\n" \ + "1: xr %0,%0\n" \ + "2:\n" \ + ".pushsection .fixup, \"ax\"\n" \ + "3: lhi %0,%3\n" \ + " jg 2b\n" \ + ".popsection\n" \ + EX_TABLE(0b,3b) EX_TABLE(1b,3b) \ + : "=d" (__rc), "+d" (val) \ + : "Q" (*(from)), "K" (-EFAULT) \ + : "cc"); \ + __rc; \ +}) + +#define __get_kernel_nofault(dst, src, type, err_label) \ +do { \ + int __gk_err; \ + \ + switch (sizeof(type)) { \ + case 1: { \ + u8 __x = 0; \ + \ + __gk_err = __get_kernel_asm(__x, (type *)(src), "ic"); \ + *((type *)(dst)) = (type)__x; \ + break; \ + }; \ + case 2: { \ + u16 __x = 0; \ + \ + __gk_err = __get_kernel_asm(__x, (type *)(src), "lh"); \ + *((type *)(dst)) = (type)__x; \ + break; \ + }; \ + case 4: { \ + u32 __x = 0; \ + \ + __gk_err = __get_kernel_asm(__x, (type *)(src), "l"); \ + *((type *)(dst)) = (type)__x; \ + break; \ + }; \ + case 8: { \ + u64 __x = 0; \ + \ + __gk_err = __get_kernel_asm(__x, (type *)(src), "lg"); \ + *((type *)(dst)) = (type)__x; \ + break; \ + }; \ + default: \ + __gk_err = __get_kernel_bad(); \ + break; \ + } \ + if (unlikely(__gk_err)) \ + goto err_label; \ +} while (0) + #endif /* __S390_UACCESS_H */ |