There are situations where fuse servers can become unresponsive or take too long to reply to a request. Currently there is no upper bound on how long a request may take, which may be frustrating to users who get stuck waiting for a request to complete. This patchset adds a timeout option for requests and two dynamically configurable fuse sysctls "default_request_timeout" and "max_request_timeout" for controlling/enforcing timeout behavior system-wide. Existing fuse servers will not be affected unless they explicitly opt into the timeout. v3: https://lore.kernel.org/linux-fsdevel/20240808190110.3188039-1-joannelkoong@xxxxxxxxx/ Changes from v3 -> v4: - Fix wording on some comments to make it more clear - Use simpler logic for timer (eg remove extra if checks, use mod timer API) (Josef) - Sanity-check should be on FR_FINISHING not FR_FINISHED (Jingbo) - Fix comment for "processing queue", add req->fpq = NULL safeguard (Bernd) v2: https://lore.kernel.org/linux-fsdevel/20240730002348.3431931-1-joannelkoong@xxxxxxxxx/ Changes from v2 -> v3: - Disarm / rearm timer in dev_do_read to handle race conditions (Bernrd) - Disarm timer in error handling for fatal interrupt (Yafang) - Clean up do_fuse_request_end (Jingbo) - Add timer for notify retrieve requests - Fix kernel test robot errors for #define no-op functions v1: https://lore.kernel.org/linux-fsdevel/20240717213458.1613347-1-joannelkoong@xxxxxxxxx/ Changes from v1 -> v2: - Add timeout for background requests - Handle resend race condition - Add sysctls Joanne Koong (2): fuse: add optional kernel-enforced timeout for requests fuse: add default_request_timeout and max_request_timeout sysctls Documentation/admin-guide/sysctl/fs.rst | 17 +++ fs/fuse/Makefile | 2 +- fs/fuse/dev.c | 192 +++++++++++++++++++++++- fs/fuse/fuse_i.h | 30 ++++ fs/fuse/inode.c | 24 +++ fs/fuse/sysctl.c | 42 ++++++ 6 files changed, 298 insertions(+), 9 deletions(-) create mode 100644 fs/fuse/sysctl.c -- 2.43.5
