4 Commits

Author SHA1 Message Date
Miklos Szeredi
f14348575d fuse: move request timeout code to a new source file
This marks the first step in cleanly separating the transport layer from
the filesystem layer.

Add "dev.h", which will contain the interface definition for the transport
layer.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2026-06-15 14:06:15 +02:00
Joanne Koong
9b17cb59a7 fuse: add default_request_timeout and max_request_timeout sysctls
Introduce two new sysctls, "default_request_timeout" and
"max_request_timeout". These control how long (in seconds) a server can
take to reply to a request. If the server does not reply by the timeout,
then the connection will be aborted. The upper bound on these sysctl
values is 65535.

"default_request_timeout" sets the default timeout if no timeout is
specified by the fuse server on mount. 0 (default) indicates no default
timeout should be enforced. If the server did specify a timeout, then
default_request_timeout will be ignored.

"max_request_timeout" sets the max amount of time the server may take to
reply to a request. 0 (default) indicates no maximum timeout. If
max_request_timeout is set and the fuse server attempts to set a
timeout greater than max_request_timeout, the system will use
max_request_timeout as the timeout. Similarly, if default_request_timeout
is greater than max_request_timeout, the system will use
max_request_timeout as the timeout. If the server does not request a
timeout and default_request_timeout is set to 0 but max_request_timeout
is set, then the timeout will be max_request_timeout.

Please note that these timeouts are not 100% precise. The request may
take roughly an extra FUSE_TIMEOUT_TIMER_FREQ seconds beyond the set max
timeout due to how it's internally implemented.

$ sysctl -a | grep fuse.default_request_timeout
fs.fuse.default_request_timeout = 0

$ echo 65536 | sudo tee /proc/sys/fs/fuse/default_request_timeout
tee: /proc/sys/fs/fuse/default_request_timeout: Invalid argument

$ echo 65535 | sudo tee /proc/sys/fs/fuse/default_request_timeout
65535

$ sysctl -a | grep fuse.default_request_timeout
fs.fuse.default_request_timeout = 65535

$ echo 0 | sudo tee /proc/sys/fs/fuse/default_request_timeout
0

$ sysctl -a | grep fuse.default_request_timeout
fs.fuse.default_request_timeout = 0

[Luis Henriques: Limit the timeout to the range [FUSE_TIMEOUT_TIMER_FREQ,
fuse_max_req_timeout]]

Signed-off-by: Joanne Koong <joannelkoong@gmail.com>
Reviewed-by: Bernd Schubert <bschubert@ddn.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Reviewed-by: Luis Henriques <luis@igalia.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2025-03-31 14:59:27 +02:00
Joel Granados
1751f872cc treewide: const qualify ctl_tables where applicable
Add the const qualifier to all the ctl_tables in the tree except for
watchdog_hardlockup_sysctl, memory_allocation_profiling_sysctls,
loadpin_sysctl_table and the ones calling register_net_sysctl (./net,
drivers/inifiniband dirs). These are special cases as they use a
registration function with a non-const qualified ctl_table argument or
modify the arrays before passing them on to the registration function.

Constifying ctl_table structs will prevent the modification of
proc_handler function pointers as the arrays would reside in .rodata.
This is made possible after commit 78eb4ea25c ("sysctl: treewide:
constify the ctl_table argument of proc_handlers") constified all the
proc_handlers.

Created this by running an spatch followed by a sed command:
Spatch:
    virtual patch

    @
    depends on !(file in "net")
    disable optional_qualifier
    @

    identifier table_name != {
      watchdog_hardlockup_sysctl,
      iwcm_ctl_table,
      ucma_ctl_table,
      memory_allocation_profiling_sysctls,
      loadpin_sysctl_table
    };
    @@

    + const
    struct ctl_table table_name [] = { ... };

sed:
    sed --in-place \
      -e "s/struct ctl_table .table = &uts_kern/const struct ctl_table *table = \&uts_kern/" \
      kernel/utsname_sysctl.c

Reviewed-by: Song Liu <song@kernel.org>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org> # for kernel/trace/
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> # SCSI
Reviewed-by: Darrick J. Wong <djwong@kernel.org> # xfs
Acked-by: Jani Nikula <jani.nikula@intel.com>
Acked-by: Corey Minyard <cminyard@mvista.com>
Acked-by: Wei Liu <wei.liu@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Bill O'Donnell <bodonnel@redhat.com>
Acked-by: Baoquan He <bhe@redhat.com>
Acked-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Acked-by: Anna Schumaker <anna.schumaker@oracle.com>
Signed-off-by: Joel Granados <joel.granados@kernel.org>
2025-01-28 13:48:37 +01:00
Joanne Koong
2b3933b1e0 fuse: enable dynamic configuration of fuse max pages limit (FUSE_MAX_MAX_PAGES)
Introduce the capability to dynamically configure the max pages limit
(FUSE_MAX_MAX_PAGES) through a sysctl. This allows system administrators
to dynamically set the maximum number of pages that can be used for
servicing requests in fuse.

Previously, this is gated by FUSE_MAX_MAX_PAGES which is statically set
to 256 pages. One result of this is that the buffer size for a write
request is limited to 1 MiB on a 4k-page system.

The default value for this sysctl is the original limit (256 pages).

$ sysctl -a | grep max_pages_limit
fs.fuse.max_pages_limit = 256

$ sysctl -n fs.fuse.max_pages_limit
256

$ echo 1024 | sudo tee /proc/sys/fs/fuse/max_pages_limit
1024

$ sysctl -n fs.fuse.max_pages_limit
1024

$ echo 65536 | sudo tee /proc/sys/fs/fuse/max_pages_limit
tee: /proc/sys/fs/fuse/max_pages_limit: Invalid argument

$ echo 0 | sudo tee /proc/sys/fs/fuse/max_pages_limit
tee: /proc/sys/fs/fuse/max_pages_limit: Invalid argument

$ echo 65535 | sudo tee /proc/sys/fs/fuse/max_pages_limit
65535

$ sysctl -n fs.fuse.max_pages_limit
65535

Signed-off-by: Joanne Koong <joannelkoong@gmail.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2024-10-25 17:05:49 +02:00