After the fuse daemon crashes, the fuse mount point becomes inaccessible. In some production environments, a watchdog daemon is used to preserve the FUSE connection's file descriptor (fd). When the FUSE daemon crashes, a new FUSE daemon is restarted and takes over the fd from the watchdog daemon, allowing it to continue providing services. However, if any inflight requests are lost during the crash, the user process becomes stuck as it does not receive any replies. To resolve this issue, this patchset introduces two sysfs APIs that enable flushing or resending these pending requests for recovery. The flush operation ends the pending request and returns an error to the application, allowing the stuck user process to recover. While returning an error may not be suitable for all scenarios, the resend API can be used to resend the these pending requests. When using the resend API, FUSE daemon needs to ensure proper recording and avoidance of processing duplicate non-idempotent requests to prevent potential consistency issues. Ma Jie Yue (1): fuse: Introduce sysfs API for flushing pending requests Peng Tao (1): fuse: Introduce sysfs API for resend pending requests fs/fuse/control.c | 40 ++++++++++++++++++++ fs/fuse/dev.c | 94 +++++++++++++++++++++++++++++++++++++++++++++++ fs/fuse/fuse_i.h | 8 +++- 3 files changed, 141 insertions(+), 1 deletion(-) -- 2.32.0.3.g01195cf9f
