From: Thomas Gleixner <[email protected]> Replace the open coded implementation with the new get/put_user_masked() helpers.
No functional change intended Signed-off-by: Thomas Gleixner <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Darren Hart <[email protected]> Cc: Davidlohr Bueso <[email protected]> Cc: "André Almeida" <[email protected]> --- V3: Adapt to scope changes V2: Convert to scoped variant --- kernel/futex/futex.h | 37 ++----------------------------------- 1 file changed, 2 insertions(+), 35 deletions(-) --- --- a/kernel/futex/futex.h +++ b/kernel/futex/futex.h @@ -285,48 +285,15 @@ static inline int futex_cmpxchg_value_lo * This does a plain atomic user space read, and the user pointer has * already been verified earlier by get_futex_key() to be both aligned * and actually in user space, just like futex_atomic_cmpxchg_inatomic(). - * - * We still want to avoid any speculation, and while __get_user() is - * the traditional model for this, it's actually slower than doing - * this manually these days. - * - * We could just have a per-architecture special function for it, - * the same way we do futex_atomic_cmpxchg_inatomic(), but rather - * than force everybody to do that, write it out long-hand using - * the low-level user-access infrastructure. - * - * This looks a bit overkill, but generally just results in a couple - * of instructions. */ static __always_inline int futex_get_value(u32 *dest, u32 __user *from) { - u32 val; - - if (can_do_masked_user_access()) - from = masked_user_access_begin(from); - else if (!user_read_access_begin(from, sizeof(*from))) - return -EFAULT; - unsafe_get_user(val, from, Efault); - user_read_access_end(); - *dest = val; - return 0; -Efault: - user_read_access_end(); - return -EFAULT; + return get_user_masked(*dest, from) ? 0 : -EFAULT; } static __always_inline int futex_put_value(u32 val, u32 __user *to) { - if (can_do_masked_user_access()) - to = masked_user_access_begin(to); - else if (!user_write_access_begin(to, sizeof(*to))) - return -EFAULT; - unsafe_put_user(val, to, Efault); - user_write_access_end(); - return 0; -Efault: - user_write_access_end(); - return -EFAULT; + return put_user_masked(val, to) ? 0 : -EFAULT; } static inline int futex_get_value_locked(u32 *dest, u32 __user *from)
