From b9d6ba94b875192ef5e2dab92d72beea33b83c3d Mon Sep 17 00:00:00 2001 From: Jeff Layton Date: Thu, 20 Dec 2012 14:59:40 -0500 Subject: [PATCH] vfs: add a retry_estale helper function to handle retries on ESTALE This function is expected to be called from path-based syscalls to help them decide whether to try the lookup and call again in the event that they got an -ESTALE return back on an earier try. Currently, we only retry the call once on an ESTALE error, but in the event that we decide that that's not enough in the future, we should be able to change the logic in this helper without too much effort. Signed-off-by: Jeff Layton Signed-off-by: Al Viro --- include/linux/namei.h | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/include/linux/namei.h b/include/linux/namei.h index 4bf19d8174ed..66542b644804 100644 --- a/include/linux/namei.h +++ b/include/linux/namei.h @@ -98,4 +98,20 @@ static inline void nd_terminate_link(void *name, size_t len, size_t maxlen) ((char *) name)[min(len, maxlen)] = '\0'; } +/** + * retry_estale - determine whether the caller should retry an operation + * @error: the error that would currently be returned + * @flags: flags being used for next lookup attempt + * + * Check to see if the error code was -ESTALE, and then determine whether + * to retry the call based on whether "flags" already has LOOKUP_REVAL set. + * + * Returns true if the caller should try the operation again. + */ +static inline bool +retry_estale(const long error, const unsigned int flags) +{ + return error == -ESTALE && !(flags & LOOKUP_REVAL); +} + #endif /* _LINUX_NAMEI_H */