Currently in libfuse, the buffer size for a fuse session is
capped at 1 MiB on a 4k page system. A recent patch
upstream [1] was merged that allows the max number of pages
per fuse request to be dynamically configurable through the
/proc/sys interface (/proc/sys/fs/fuse/max_pages_limit).
This commit adds support for this on the libfuse side to set
the fuse session buffer to take into account the max pages
limit set in /proc/sys/fs/fuse/max_pages_limit. If this
sysctl does not exist (eg older kernels), it will default to
old behavior (using FUSE_MAX_MAX_PAGES (256) as the max pages
limit). This allows for things like bigger write buffers per
request.
[1] https://lore.kernel.org/linux-fsdevel/20240923171311.1561917-1-joannelkoong@gmail.com/T/#t
close_range() is much more efficient.
Also remove the lower limit of 3 and set it to 0, as 0 to 1
might have been closed by the application and might be valid.
When using the auto_unmount option, the fusermount3
watchdog process retains any inherited file descriptors.
This PR ensures they are closed.
Reason is that FDs that are kept open for a long time might
cause issues for applications using libfuse, for example
if these expect a pipe close, but the pipe is kept open
through the inherited file descriptor.
See for example: https://github.com/cvmfs/cvmfs/issues/3645
Signed-off-by: MJ Harvey <mharvey@jumptrading.com>
Signed-off-by: Bernd Schubert <bschubert@ddn.com>
sfs_open and sfs_create set fi->direct_io (FOPEN_DIRECT_IO) when
O_DIRECT is given, in order to benefit from a shared inode lock
in kernel, i.e. to get parallel DIO writes. However, kernel side
disabled passthrough when FOPEN_DIRECT_IO is set. Reads/writes
had been totally failing in this case for O_DIRECT as
sfs_write_buf() and sfs_read() have a sanity check. That sanity
check could be modified, but for performance passthrough is
better than parallel DIO, hence, we only want automatic
FOPEN_DIRECT_IO for O_DIRECT when passthrough is not enabled.
Fixes: https://github.com/libfuse/libfuse/issues/1027
This also fixes automatically switching to FOPEN_DIRECT_IO
for O_DIRECT in sfs_create().
umount2 is called with privs dropped, not raised. This
works around a clash with NFS permissions: if FUSE mounted
on NFS client directory with root_squash in effect, and
some directory in the path leading to the mount point denies
permissions to others, umount2 will fail because userid 0
cannot search it. Since drop_privs merely sets the file-
system user- and group-ID without changing the CAP_SYS_ADMIN
capability needed to unmount a file system (which fusermount
has because it is set-user-ID root), umount2 works fine.
This is an addition to commit e75d2c54a3. This example sets
FUSE_USE_VERSION = 34 but uses fuse_loop_cfg_* APIs, which is
not allowed since these APIs are not introduced in version 34.
The option to the path of the binary had been accidentally removed
in the scripts that can parse backtraces.
The dump_stack() function had left over debug messages.
This is an addition to commit a8f1ae35af, which
introduced the 312 API, but didn't set the right
API version in all examples.
Signed-off-by: Bernd Schubert <bschubert@ddn.com>
Commit 170edc6a8e added dot and dotdot (. and ..) to readdir
results, but introduced an issue when max number of entries
was reached - lookup count must not be decreased without
doing the lookup.
With ext4 as underlying file system readir seems to return . and ..
at random offsets and randomly failed xfstests for me.
This also fixes indentation, as passthrough_hp.cc does not follow
the linux indentation style (if we decide to fix this, it needs
to be done for the entire file).
Signed-off-by: Bernd Schubert <bschubert@ddn.com>
I see random ENOTCONN failures in xfstest generic/013 and generic/014
in my branch, but earliest on the 2nd run - takes ~12hours to get
the issue, but then there are no further information logged.
ENOTCONN points to a daemon crash - I need backtraces and a core dump.
This adds optional handling of fatal signals to print a core dump
and optional syslog logging with these new public functions:
fuse_set_fail_signal_handlers()
In addition to the existing fuse_set_signal_handlers(). This is not
enabled together with fuse_set_signal_handlers(), as it is change
in behavior and file systems might already have their own fatal
handlers.
fuse_log_enable_syslog
Print logs to syslog instead of stderr
fuse_log_close_syslog
Close syslog (for now just does closelog())
Code in fuse_signals.c is also updated, to be an array of signals,
and setting signal handlers is now down with a for-loop instead
of one hand coded set_one_signal_handler() per signal.
generic/401 fails currently because it checks that "." and ".." are
listed as directory entries.
Include "." and ".." as listed directory entries in passthrough_hp's
readdir implementation.
Signed-off by: Joanne Koong <joannelkoong@gmail.com>
This is to document operations and to also list
their in/out arguments.
This list was auto generated and only partly verified,
use with care. Not all operations are supported by
libfuse yet.
dmask: umask applied to directories
fmask: umask applied to non-directories
to get "typical" permission bits for regular files (0644) and directories (0755), a single
umask option is not sufficient (or well, it isn't the way fuse implements it)
there is precident for separate umask and dmask options in other
filesystems (see for example fat: https://github.com/torvalds/linux/tree/master/fs/fat)
this addition should not affect backward-compatibility; the original
umask option retains the same meaning, but non-zero fmask or
dmask will override it.
After reading the file /proc/$PID/task/$PID/status the buffer wasn't
terminated with a null character. This could theoretically lead to buffer
overrun by the subsequent strstr() call.
Since the contents of the proc file are guaranteed to contain the pattern
that strstr is looking for, this doesn't happen in normal situations.
Add null termination for robustness.
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
The code `fuse_init_intr_signal` in `_fuse_new_317` is useless
since commit 8ee553dac ("fuse_new(): don't accept options that
don't make sense for end-users") has remove the conf.intr option
for end-users. The conf.intr is always zero (i.e., disabled) here.
Move `fuse_init_intr_signal` after the user-defined `init()` function,
so that conf.intr and conf.intr_signal has been configured by the user.
generic/003 fails currently because if you specify -o relatime we will
fail to mount, but not return an error, so the test thinks that we
support relatime and then hilarity ensues. Set ret so that if we get
any failures while trying to mount we will properly error out.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
The variable is not modified exclusively with locks since commit
cef8c8b249 ("Add support for no_interrupt") anymore.
That commit is safe, but might be error prone to future updates.
Changing it to a C11 _Atomic should avoid issues.
The function fuse_session_process_buf_int() would do much things
for FUSE_INTERRUPT requests, even there are no FUSE_INTERRUPT requests:
1. check every non-FUSE_INTERRUPT request and add these requests to the
linked list(se->list) under a big lock(se->lock).
2. the function fuse_free_req() frees every request and remove them from
the linked list(se->list) under a bing lock(se->lock).
These operations are not meaningful when there are no FUSE_INTERRUPT requests,
and have a great impact on the performance of fuse filesystem because the big
lock for each request.
In some cases, FUSE_INTERRUPT requests are infrequent, even none at all.
Besides, the user-defined filesystem may do nothing for FUSE_INTERRUPT requests.
And the kernel side has the option "no_interrupt" in struct fuse_conn. This kernel option
can be enabled by return ENOSYS in libfuse for the reply of FUSE_INTERRUPT request.
But I don't find the code to enable the "no_interrupt" kernel option in libfuse.
So add the no_interrupt support, and when this operaion is enabled:
1. remove the useless locking operaions and list operations.
2. return ENOSYS for the reply of FUSE_INTERRUPT request to inform the kernel to disable
FUSE_INTERRUPT request.
