From 9f6c532f59b20580acf8ede9409c9b8dce6e74e1 Mon Sep 17 00:00:00 2001 From: "peterz@infradead.org" Date: Thu, 21 Sep 2023 12:45:10 +0200 Subject: futex: Add sys_futex_wake() To complement sys_futex_waitv() add sys_futex_wake(). This syscall implements what was previously known as FUTEX_WAKE_BITSET except it uses 'unsigned long' for the bitmask and takes FUTEX2 flags. The 'unsigned long' allows FUTEX2_SIZE_U64 on 64bit platforms. Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Thomas Gleixner Acked-by: Geert Uytterhoeven Link: https://lore.kernel.org/r/20230921105247.936205525@noisy.programming.kicks-ass.net --- kernel/futex/syscalls.c | 30 ++++++++++++++++++++++++++++++ 1 file changed, 30 insertions(+) (limited to 'kernel/futex') diff --git a/kernel/futex/syscalls.c b/kernel/futex/syscalls.c index 2339f9ccee7f..7049a52ef68e 100644 --- a/kernel/futex/syscalls.c +++ b/kernel/futex/syscalls.c @@ -306,6 +306,36 @@ destroy_timer: return ret; } +/* + * sys_futex_wake - Wake a number of futexes + * @uaddr: Address of the futex(es) to wake + * @mask: bitmask + * @nr: Number of the futexes to wake + * @flags: FUTEX2 flags + * + * Identical to the traditional FUTEX_WAKE_BITSET op, except it is part of the + * futex2 family of calls. + */ + +SYSCALL_DEFINE4(futex_wake, + void __user *, uaddr, + unsigned long, mask, + int, nr, + unsigned int, flags) +{ + if (flags & ~FUTEX2_VALID_MASK) + return -EINVAL; + + flags = futex2_to_flags(flags); + if (!futex_flags_valid(flags)) + return -EINVAL; + + if (!futex_validate_input(flags, mask)) + return -EINVAL; + + return futex_wake(uaddr, flags, nr, mask); +} + #ifdef CONFIG_COMPAT COMPAT_SYSCALL_DEFINE2(set_robust_list, struct compat_robust_list_head __user *, head, -- cgit