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| author |   Will Deacon <will.deacon@arm.com> | 2019-04-10 11:51:54 +0100 |
|---|---|---|
| committer | Will Deacon <will.deacon@arm.com> | 2019-04-26 13:57:55 +0100 |
| commit | 427503519739e779c0db8afe876c1b33f3ac60ae (patch) | |
| tree | adb1c420287cb4a6fe1e84b098ef51eb61d964a0 /include/asm-generic/futex.h | |
| parent | arm64: futex: Avoid copying out uninitialised stack in failed cmpxchg() (diff) | |
| download | wireguard-linux-427503519739e779c0db8afe876c1b33f3ac60ae.tar.xz wireguard-linux-427503519739e779c0db8afe876c1b33f3ac60ae.zip | |
futex: Update comments and docs about return values of arch futex code
The architecture implementations of 'arch_futex_atomic_op_inuser()' and
'futex_atomic_cmpxchg_inatomic()' are permitted to return only -EFAULT,
-EAGAIN or -ENOSYS in the case of failure.
Update the comments in the asm-generic/ implementation and also a stray
reference in the robust futex documentation.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Diffstat (limited to 'include/asm-generic/futex.h')
| -rw-r--r-- | include/asm-generic/futex.h | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/include/asm-generic/futex.h b/include/asm-generic/futex.h index fcb61b4659b3..8666fe7f35d7 100644 --- a/include/asm-generic/futex.h +++ b/include/asm-generic/futex.h @@ -23,7 +23,9 @@ * * Return: * 0 - On success - * <0 - On error + * -EFAULT - User access resulted in a page fault + * -EAGAIN - Atomic operation was unable to complete due to contention + * -ENOSYS - Operation not supported */ static inline int arch_futex_atomic_op_inuser(int op, u32 oparg, int *oval, u32 __user *uaddr) @@ -85,7 +87,9 @@ out_pagefault_enable: * * Return: * 0 - On success - * <0 - On error + * -EFAULT - User access resulted in a page fault + * -EAGAIN - Atomic operation was unable to complete due to contention + * -ENOSYS - Function not implemented (only if !HAVE_FUTEX_CMPXCHG) */ static inline int futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr, |