user/sven/linux.git/include/uapi/linux/fuse.h, branch v4.20.13

fuse: enable caching of symlinks

2018-10-15T13:43:07Z

FUSE file reads are cached in the page cache, but symlink reads are not. This patch enables FUSE READLINK operations to be cached which can improve performance of some FUSE workloads. In particular, I'm working on a FUSE filesystem for access to source code and discovered that about a 10% improvement to build times is achieved with this patch (there are a lot of symlinks in the source tree). Signed-off-by: Miklos Szeredi

fuse: add max_pages to init_out

2018-10-01T08:07:06Z

Replace FUSE_MAX_PAGES_PER_REQ with the configurable parameter max_pages to improve performance. Old RFC with detailed description of the problem and many fixes by Mitsuo Hayasaka (mitsuo.hayasaka.hu@hitachi.com): - https://lkml.org/lkml/2012/7/5/136 We've encountered performance degradation and fixed it on a big and complex virtual environment. Environment to reproduce degradation and improvement: 1. Add lag to user mode FUSE Add nanosleep(&(struct timespec){ 0, 1000 }, NULL); to xmp_write_buf in passthrough_fh.c 2. patch UM fuse with configurable max_pages parameter. The patch will be provided latter. 3. run test script and perform test on tmpfs fuse_test() { cd /tmp mkdir -p fusemnt passthrough_fh -o max_pages=$1 /tmp/fusemnt grep fuse /proc/self/mounts dd conv=fdatasync oflag=dsync if=/dev/zero of=fusemnt/tmp/tmp \ count=1K bs=1M 2>&1 | grep -v records rm fusemnt/tmp/tmp killall passthrough_fh } Test results: passthrough_fh /tmp/fusemnt fuse.passthrough_fh \ rw,nosuid,nodev,relatime,user_id=0,group_id=0 0 0 1073741824 bytes (1.1 GB) copied, 1.73867 s, 618 MB/s passthrough_fh /tmp/fusemnt fuse.passthrough_fh \ rw,nosuid,nodev,relatime,user_id=0,group_id=0,max_pages=256 0 0 1073741824 bytes (1.1 GB) copied, 1.15643 s, 928 MB/s Obviously with bigger lag the difference between 'before' and 'after' will be more significant. Mitsuo Hayasaka, in 2012 (https://lkml.org/lkml/2012/7/5/136), observed improvement from 400-550 to 520-740. Signed-off-by: Constantine Shulyupin Signed-off-by: Miklos Szeredi

fuse: add FOPEN_CACHE_DIR

2018-09-28T14:43:23Z

Add flag returned by OPENDIR request to allow kernel to cache directory contents in page cache. The effect of FOPEN_CACHE_DIR is twofold: a) if not already cached, it writes entries into the cache b) if already cached, it allows reading entries from the cache The FOPEN_KEEP_CACHE has the same effect as on regular files: unless this flag is given the cache is cleared upon completion of open. So FOPEN_KEEP_CACHE and FOPEN_KEEP_CACHE flags should be used together to make use of the directory caching facility introduced in the following patches. The FUSE_AUTO_INVAL_DATA flag returned in INIT reply also has the same affect on the directory cache as it has on data cache for regular files. Signed-off-by: Miklos Szeredi

fuse: add support for copy_file_range()

2018-09-28T14:43:22Z

There are several FUSE filesystems that can implement server-side copy or other efficient copy/duplication/clone methods. The copy_file_range() syscall is the standard interface that users have access to while not depending on external libraries that bypass FUSE. Signed-off-by: Niels de Vos Signed-off-by: Miklos Szeredi

fuse: return -ECONNABORTED on /dev/fuse read after abort

2018-03-20T16:11:44Z

Currently the userspace has no way of knowing whether the fuse connection ended because of umount or abort via sysfs. It makes it hard for filesystems to free the mountpoint after abort without worrying about removing some new mount. The patch fixes it by returning different errors when userspace reads from /dev/fuse (-ENODEV for umount and -ECONNABORTED for abort). Add a new capability flag FUSE_ABORT_ERROR. If set and the connection is gone because of sysfs abort, reading from the device will return -ECONNABORTED. Signed-off-by: Szymon Lukasz Signed-off-by: Miklos Szeredi

License cleanup: add SPDX license identifier to uapi header files with a license

2017-11-02T10:20:11Z

Many user space API headers have licensing information, which is either incomplete, badly formatted or just a shorthand for referring to the license under which the file is supposed to be. This makes it hard for compliance tools to determine the correct license. Update these files with an SPDX license identifier. The identifier was chosen based on the license information in the file. GPL/LGPL licensed headers get the matching GPL/LGPL SPDX license identifier with the added 'WITH Linux-syscall-note' exception, which is the officially assigned exception identifier for the kernel syscall exception: NOTE! This copyright does *not* cover user programs that use kernel services by normal system calls - this is merely considered normal use of the kernel, and does *not* fall under the heading of "derived work". This exception makes it possible to include GPL headers into non GPL code, without confusing license compliance tools. Headers which have either explicit dual licensing or are just licensed under a non GPL license are updated with the corresponding SPDX identifier and the GPLv2 with syscall exception identifier. The format is: ((GPL-2.0 WITH Linux-syscall-note) OR SPDX-ID-OF-OTHER-LICENSE) SPDX license identifiers are a legally binding shorthand, which can be used instead of the full boiler plate text. The update does not remove existing license information as this has to be done on a case by case basis and the copyright holders might have to be consulted. This will happen in a separate step. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. See the previous patch in this series for the methodology of how this patch was researched. Reviewed-by: Kate Stewart Reviewed-by: Philippe Ombredanne Reviewed-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

fuse: Add posix ACL support

2016-10-01T05:32:32Z

Add a new INIT flag, FUSE_POSIX_ACL, for negotiating ACL support with userspace. When it is set in the INIT response, ACL support will be enabled. ACL support also implies "default_permissions". When ACL support is enabled, the kernel will cache and have responsibility for enforcing ACLs. ACL xattrs will be passed to userspace, which is responsible for updating the ACLs in the filesystem, keeping the file mode in sync, and inheritance of default ACLs when new filesystem nodes are created. Signed-off-by: Seth Forshee Signed-off-by: Miklos Szeredi

fuse: handle killpriv in userspace fs

2016-10-01T05:32:32Z

Only userspace filesystem can do the killing of suid/sgid without races. So introduce an INIT flag and negotiate support for this. Signed-off-by: Miklos Szeredi

fuse: serialize dirops by default

2016-06-30T11:10:49Z

Negotiate with userspace filesystems whether they support parallel readdir and lookup. Disable parallelism by default for fear of breaking fuse filesystems. Signed-off-by: Miklos Szeredi Fixes: 9902af79c01a ("parallel lookups: actual switch to rwsem") Fixes: d9b3dbdcfd62 ("fuse: switch to ->iterate_shared()")

fuse: add support for SEEK_HOLE and SEEK_DATA in lseek

2015-11-10T09:32:37Z

A useful performance improvement for accessing virtual machine images via FUSE mount. See https://bugzilla.redhat.com/show_bug.cgi?id=1220173 for a use-case for glusterFS. Signed-off-by: Ravishankar N Signed-off-by: Miklos Szeredi