diff options
| author | Gerald Schaefer <geraldsc@de.ibm.com> | 2006-12-04 15:40:45 +0100 |
|---|---|---|
| committer | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2006-12-04 15:40:45 +0100 |
| commit | 59f35d53fde3987d071ea1c9bf1c9ba29fcb69fe (patch) | |
| tree | 50853c1bf3ad3af080707fb2e6b3722d3d86db9e /arch/s390/lib/uaccess_mvcos.c | |
| parent | d57de5a36791cb1b7285649c62f183b0d3505f7d (diff) | |
[S390] Add dynamic size check for usercopy functions.
Use a wrapper for copy_to/from_user to chose the best usercopy method.
The mvcos instruction is better for sizes greater than 256 bytes, if
mvcos is not available a page table walk is better for sizes greater
than 1024 bytes. Also removed the redundant copy_to/from_user_std_small
functions.
Signed-off-by: Gerald Schaefer <geraldsc@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'arch/s390/lib/uaccess_mvcos.c')
| -rw-r--r-- | arch/s390/lib/uaccess_mvcos.c | 27 |
1 files changed, 21 insertions, 6 deletions
diff --git a/arch/s390/lib/uaccess_mvcos.c b/arch/s390/lib/uaccess_mvcos.c index 121b2935a42..f9a23d57eb7 100644 --- a/arch/s390/lib/uaccess_mvcos.c +++ b/arch/s390/lib/uaccess_mvcos.c @@ -27,6 +27,9 @@ #define SLR "slgr" #endif +extern size_t copy_from_user_std(size_t, const void __user *, void *); +extern size_t copy_to_user_std(size_t, void __user *, const void *); + size_t copy_from_user_mvcos(size_t size, const void __user *ptr, void *x) { register unsigned long reg0 asm("0") = 0x81UL; @@ -66,6 +69,13 @@ size_t copy_from_user_mvcos(size_t size, const void __user *ptr, void *x) return size; } +size_t copy_from_user_mvcos_check(size_t size, const void __user *ptr, void *x) +{ + if (size <= 256) + return copy_from_user_std(size, ptr, x); + return copy_from_user_mvcos(size, ptr, x); +} + size_t copy_to_user_mvcos(size_t size, void __user *ptr, const void *x) { register unsigned long reg0 asm("0") = 0x810000UL; @@ -95,6 +105,13 @@ size_t copy_to_user_mvcos(size_t size, void __user *ptr, const void *x) return size; } +size_t copy_to_user_mvcos_check(size_t size, void __user *ptr, const void *x) +{ + if (size <= 256) + return copy_to_user_std(size, ptr, x); + return copy_to_user_mvcos(size, ptr, x); +} + size_t copy_in_user_mvcos(size_t size, void __user *to, const void __user *from) { register unsigned long reg0 asm("0") = 0x810081UL; @@ -145,18 +162,16 @@ size_t clear_user_mvcos(size_t size, void __user *to) return size; } -extern size_t copy_from_user_std_small(size_t, const void __user *, void *); -extern size_t copy_to_user_std_small(size_t, void __user *, const void *); extern size_t strnlen_user_std(size_t, const char __user *); extern size_t strncpy_from_user_std(size_t, const char __user *, char *); extern int futex_atomic_op(int, int __user *, int, int *); extern int futex_atomic_cmpxchg(int __user *, int, int); struct uaccess_ops uaccess_mvcos = { - .copy_from_user = copy_from_user_mvcos, - .copy_from_user_small = copy_from_user_std_small, - .copy_to_user = copy_to_user_mvcos, - .copy_to_user_small = copy_to_user_std_small, + .copy_from_user = copy_from_user_mvcos_check, + .copy_from_user_small = copy_from_user_std, + .copy_to_user = copy_to_user_mvcos_check, + .copy_to_user_small = copy_to_user_std, .copy_in_user = copy_in_user_mvcos, .clear_user = clear_user_mvcos, .strnlen_user = strnlen_user_std, |