summaryrefslogtreecommitdiffstats
path: root/fs/fuse/inode.c
Commit message (Collapse)AuthorAgeFilesLines
* fuse: share lookup state between submount and its parentKrister Johansen2023-12-041-3/+72
| | | | | | | | | | | | | | | | | | | | | | | | Fuse submounts do not perform a lookup for the nodeid that they inherit from their parent. Instead, the code decrements the nlookup on the submount's fuse_inode when it is instantiated, and no forget is performed when a submount root is evicted. Trouble arises when the submount's parent is evicted despite the submount itself being in use. In this author's case, the submount was in a container and deatched from the initial mount namespace via a MNT_DEATCH operation. When memory pressure triggered the shrinker, the inode from the parent was evicted, which triggered enough forgets to render the submount's nodeid invalid. Since submounts should still function, even if their parent goes away, solve this problem by sharing refcounted state between the parent and its submount. When all of the references on this shared state reach zero, it's safe to forget the final lookup of the fuse nodeid. Signed-off-by: Krister Johansen <kjlx@templeofstupid.com> Cc: stable@vger.kernel.org Fixes: 1866d779d5d2 ("fuse: Allow fuse_fill_super_common() for submounts") Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* fuse: Rename DIRECT_IO_RELAX to DIRECT_IO_ALLOW_MMAPTyler Fanelli2023-12-041-3/+3
| | | | | | | | | | | | | | | | | | Although DIRECT_IO_RELAX's initial usage is to allow shared mmap, its description indicates a purpose of reducing memory footprint. This may imply that it could be further used to relax other DIRECT_IO operations in the future. Replace it with a flag DIRECT_IO_ALLOW_MMAP which does only one thing, allow shared mmap of DIRECT_IO files while still bypassing the cache on regular reads and writes. [Miklos] Also Keep DIRECT_IO_RELAX definition for backward compatibility. Signed-off-by: Tyler Fanelli <tfanelli@redhat.com> Fixes: e78662e818f9 ("fuse: add a new fuse init flag to relax restrictions in no cache mode") Cc: <stable@vger.kernel.org> # v6.6 Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* Merge tag 'vfs-6.7.fsid' of ↵Linus Torvalds2023-11-071-3/+4
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull vfs fanotify fsid updates from Christian Brauner: "This work is part of the plan to enable fanotify to serve as a drop-in replacement for inotify. While inotify is availabe on all filesystems, fanotify currently isn't. In order to support fanotify on all filesystems two things are needed: (1) all filesystems need to support AT_HANDLE_FID (2) all filesystems need to report a non-zero f_fsid This contains (1) and allows filesystems to encode non-decodable file handlers for fanotify without implementing any exportfs operations by encoding a file id of type FILEID_INO64_GEN from i_ino and i_generation. Filesystems that want to opt out of encoding non-decodable file ids for fanotify that don't support NFS export can do so by providing an empty export_operations struct. This also partially addresses (2) by generating f_fsid for simple filesystems as well as freevxfs. Remaining filesystems will be dealt with by separate patches. Finally, this contains the patch from the current exportfs maintainers which moves exportfs under vfs with Chuck, Jeff, and Amir as maintainers and vfs.git as tree" * tag 'vfs-6.7.fsid' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: MAINTAINERS: create an entry for exportfs fs: fix build error with CONFIG_EXPORTFS=m or not defined freevxfs: derive f_fsid from bdev->bd_dev fs: report f_fsid from s_dev for "simple" filesystems exportfs: support encoding non-decodeable file handles by default exportfs: define FILEID_INO64_GEN* file handle types exportfs: make ->encode_fh() a mandatory method for NFS export exportfs: add helpers to check if filesystem can encode/decode file handles
| * exportfs: define FILEID_INO64_GEN* file handle typesAmir Goldstein2023-10-281-3/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Similar to the common FILEID_INO32* file handle types, define common FILEID_INO64* file handle types. The type values of FILEID_INO64_GEN and FILEID_INO64_GEN_PARENT are the values returned by fuse and xfs for 64bit ino encoded file handle types. Note that these type value are filesystem specific and they do not define a universal file handle format, for example: fuse encodes FILEID_INO64_GEN as [ino-hi32,ino-lo32,gen] and xfs encodes FILEID_INO64_GEN as [hostr-order-ino64,gen] (a.k.a xfs_fid64). The FILEID_INO64_GEN fhandle type is going to be used for file ids for fanotify from filesystems that do not support NFS export. Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Amir Goldstein <amir73il@gmail.com> Link: https://lore.kernel.org/r/20231023180801.2953446-4-amir73il@gmail.com Signed-off-by: Christian Brauner <brauner@kernel.org>
* | fuse: convert to new timestamp accessorsJeff Layton2023-10-181-15/+14
|/ | | | | | | | Convert to using the new inode timestamp accessor functions. Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://lore.kernel.org/r/20231004185347.80880-37-jlayton@kernel.org Signed-off-by: Christian Brauner <brauner@kernel.org>
* Merge tag 'fuse-update-6.6' of ↵Linus Torvalds2023-09-051-5/+29
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse Pull fuse updates from Miklos Szeredi: - Revert non-waiting FLUSH due to a regression - Fix a lookup counter leak in readdirplus - Add an option to allow shared mmaps in no-cache mode - Add btime support and statx intrastructure to the protocol - Invalidate positive/negative dentry on failed create/delete * tag 'fuse-update-6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse: fuse: conditionally fill kstat in fuse_do_statx() fuse: invalidate dentry on EEXIST creates or ENOENT deletes fuse: cache btime fuse: implement statx fuse: add ATTR_TIMEOUT macro fuse: add STATX request fuse: handle empty request_mask in statx fuse: write back dirty pages before direct write in direct_io_relax mode fuse: add a new fuse init flag to relax restrictions in no cache mode fuse: invalidate page cache pages before direct write fuse: nlookup missing decrement in fuse_direntplus_link Revert "fuse: in fuse_flush only wait if someone wants the return code"
| * fuse: cache btimeMiklos Szeredi2023-08-211-2/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Not all inode attributes are supported by all filesystems, but for the basic stats (which are returned by stat(2) and friends) all of them will have some value, even if that doesn't reflect a real attribute of the file. Btime is different, in that filesystems are free to report or not report a value in statx. If the value is available, then STATX_BTIME bit is set in stx_mask. When caching the value of btime, remember the availability of the attribute as well as the value (if available). This is done by using the FUSE_I_BTIME bit in fuse_inode->state to indicate availability, while using fuse_inode->inval_mask & STATX_BTIME to indicate the state of the cache itself (i.e. set if cache is invalid, and cleared if cache is valid). Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
| * fuse: implement statxMiklos Szeredi2023-08-211-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Allow querying btime. When btime is requested in mask, then FUSE_STATX request is sent. Otherwise keep using FUSE_GETATTR. The userspace interface for statx matches that of the statx(2) API. However there are limitations on how this interface is used: - returned basic stats and btime are used, stx_attributes, etc. are ignored - always query basic stats and btime, regardless of what was requested - requested sync type is ignored, the default is passed to the server - if server returns with some attributes missing from the result_mask, then no attributes will be cached - btime is not cached yet (next patch will fix that) For new inodes initialize fi->inval_mask to "all invalid", instead of "all valid" as previously. Also only clear basic stats from inval_mask when caching attributes. This will result in the caching logic not thinking that btime is cached. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
| * fuse: add a new fuse init flag to relax restrictions in no cache modeHao Xu2023-08-161-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | FOPEN_DIRECT_IO is usually set by fuse daemon to indicate need of strong coherency, e.g. network filesystems. Thus shared mmap is disabled since it leverages page cache and may write to it, which may cause inconsistence. But FOPEN_DIRECT_IO can be used not for coherency but to reduce memory footprint as well, e.g. reduce guest memory usage with virtiofs. Therefore, add a new fuse init flag FUSE_DIRECT_IO_RELAX to relax restrictions in that mode, currently, it allows shared mmap. One thing to note is to make sure it doesn't break coherency in your use case. Signed-off-by: Hao Xu <howeyxu@tencent.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* | Merge tag 'v6.6-vfs.ctime' of ↵Linus Torvalds2023-08-281-8/+8
|\ \ | |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull vfs timestamp updates from Christian Brauner: "This adds VFS support for multi-grain timestamps and converts tmpfs, xfs, ext4, and btrfs to use them. This carries acks from all relevant filesystems. The VFS always uses coarse-grained timestamps when updating the ctime and mtime after a change. This has the benefit of allowing filesystems to optimize away a lot of metadata updates, down to around 1 per jiffy, even when a file is under heavy writes. Unfortunately, this has always been an issue when we're exporting via NFSv3, which relies on timestamps to validate caches. A lot of changes can happen in a jiffy, so timestamps aren't sufficient to help the client decide to invalidate the cache. Even with NFSv4, a lot of exported filesystems don't properly support a change attribute and are subject to the same problems with timestamp granularity. Other applications have similar issues with timestamps (e.g., backup applications). If we were to always use fine-grained timestamps, that would improve the situation, but that becomes rather expensive, as the underlying filesystem would have to log a lot more metadata updates. This introduces fine-grained timestamps that are used when they are actively queried. This uses the 31st bit of the ctime tv_nsec field to indicate that something has queried the inode for the mtime or ctime. When this flag is set, on the next mtime or ctime update, the kernel will fetch a fine-grained timestamp instead of the usual coarse-grained one. As POSIX generally mandates that when the mtime changes, the ctime must also change the kernel always stores normalized ctime values, so only the first 30 bits of the tv_nsec field are ever used. Filesytems can opt into this behavior by setting the FS_MGTIME flag in the fstype. Filesystems that don't set this flag will continue to use coarse-grained timestamps. Various preparatory changes, fixes and cleanups are included: - Fixup all relevant places where POSIX requires updating ctime together with mtime. This is a wide-range of places and all maintainers provided necessary Acks. - Add new accessors for inode->i_ctime directly and change all callers to rely on them. Plain accesses to inode->i_ctime are now gone and it is accordingly rename to inode->__i_ctime and commented as requiring accessors. - Extend generic_fillattr() to pass in a request mask mirroring in a sense the statx() uapi. This allows callers to pass in a request mask to only get a subset of attributes filled in. - Rework timestamp updates so it's possible to drop the @now parameter the update_time() inode operation and associated helpers. - Add inode_update_timestamps() and convert all filesystems to it removing a bunch of open-coding" * tag 'v6.6-vfs.ctime' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (107 commits) btrfs: convert to multigrain timestamps ext4: switch to multigrain timestamps xfs: switch to multigrain timestamps tmpfs: add support for multigrain timestamps fs: add infrastructure for multigrain timestamps fs: drop the timespec64 argument from update_time xfs: have xfs_vn_update_time gets its own timestamp fat: make fat_update_time get its own timestamp fat: remove i_version handling from fat_update_time ubifs: have ubifs_update_time use inode_update_timestamps btrfs: have it use inode_update_timestamps fs: drop the timespec64 arg from generic_update_time fs: pass the request_mask to generic_fillattr fs: remove silly warning from current_time gfs2: fix timestamp handling on quota inodes fs: rename i_ctime field to __i_ctime selinux: convert to ctime accessor functions security: convert to ctime accessor functions apparmor: convert to ctime accessor functions sunrpc: convert to ctime accessor functions ...
| * fuse: convert to ctime accessor functionsJeff Layton2023-07-241-8/+8
| | | | | | | | | | | | | | | | | | | | | | In later patches, we're going to change how the inode's ctime field is used. Switch to using accessor functions instead of raw accesses of inode->i_ctime. Signed-off-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: Jan Kara <jack@suse.cz> Message-Id: <20230705190309.579783-44-jlayton@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
* | fuse: Apply flags2 only when userspace set the FUSE_INIT_EXTBernd Schubert2023-06-071-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is just a safety precaution to avoid checking flags on memory that was initialized on the user space side. libfuse zeroes struct fuse_init_out outarg, but this is not guranteed to be done in all implementations. Better is to act on flags and to only apply flags2 when FUSE_INIT_EXT is set. There is a risk with this change, though - it might break existing user space libraries, which are already using flags2 without setting FUSE_INIT_EXT. The corresponding libfuse patch is here https://github.com/libfuse/libfuse/pull/662 Signed-off-by: Bernd Schubert <bschubert@ddn.com> Fixes: 53db28933e95 ("fuse: extend init flags") Cc: <stable@vger.kernel.org> # v5.17 Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* | fuse: add feature flag for expire-onlyMiklos Szeredi2023-06-071-1/+2
|/ | | | | | | | | | | | Add an init flag idicating whether the FUSE_EXPIRE_ONLY flag of FUSE_NOTIFY_INVAL_ENTRY is effective. This is needed for backports of this feature, otherwise the server could just check the protocol version. Fixes: 4f8d37020e1f ("fuse: add "expire only" mode to FUSE_NOTIFY_INVAL_ENTRY") Cc: <stable@vger.kernel.org> # v6.2 Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* Merge tag 'fuse-update-6.3' of ↵Linus Torvalds2023-02-271-1/+3
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse Pull fuse updates from Miklos Szeredi: - Fix regression in fileattr permission checking - Fix possible hang during PID namespace destruction - Add generic support for request extensions - Add supplementary group list extension - Add limited support for supplying supplementary groups in create requests - Documentation fixes * tag 'fuse-update-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse: fuse: add inode/permission checks to fileattr_get/fileattr_set fuse: fix all W=1 kernel-doc warnings fuse: in fuse_flush only wait if someone wants the return code fuse: optional supplementary group in create requests fuse: add request extension
| * fuse: optional supplementary group in create requestsMiklos Szeredi2023-01-261-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Permission to create an object (create, mkdir, symlink, mknod) needs to take supplementary groups into account. Add a supplementary group request extension. This can contain an arbitrary number of group IDs and can be added to any request. This extension is not added to any request by default. Add FUSE_CREATE_SUPP_GROUP init flag to enable supplementary group info in creation requests. This adds just a single supplementary group that matches the parent group in the case described above. In other cases the extension is not added. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* | fuse: fixes after adapting to new posix acl apiChristian Brauner2023-01-241-11/+10
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This cycle we ported all filesystems to the new posix acl api. While looking at further simplifications in this area to remove the last remnants of the generic dummy posix acl handlers we realized that we regressed fuse daemons that don't set FUSE_POSIX_ACL but still make use of posix acls. With the change to a dedicated posix acl api interacting with posix acls doesn't go through the old xattr codepaths anymore and instead only relies the get acl and set acl inode operations. Before this change fuse daemons that don't set FUSE_POSIX_ACL were able to get and set posix acl albeit with two caveats. First, that posix acls aren't cached. And second, that they aren't used for permission checking in the vfs. We regressed that use-case as we currently refuse to retrieve any posix acls if they aren't enabled via FUSE_POSIX_ACL. So older fuse daemons would see a change in behavior. We can restore the old behavior in multiple ways. We could change the new posix acl api and look for a dedicated xattr handler and if we find one prefer that over the dedicated posix acl api. That would break the consistency of the new posix acl api so we would very much prefer not to do that. We could introduce a new ACL_*_CACHE sentinel that would instruct the vfs permission checking codepath to not call into the filesystem and ignore acls. But a more straightforward fix for v6.2 is to do the same thing that Overlayfs does and give fuse a separate get acl method for permission checking. Overlayfs uses this to express different needs for vfs permission lookup and acl based retrieval via the regular system call path as well. Let fuse do the same for now. This way fuse can continue to refuse to retrieve posix acls for daemons that don't set FUSE_POSXI_ACL for permission checking while allowing a fuse server to retrieve it via the usual system calls. In the future, we could extend the get acl inode operation to not just pass a simple boolean to indicate rcu lookup but instead make it a flag argument. Then in addition to passing the information that this is an rcu lookup to the filesystem we could also introduce a flag that tells the filesystem that this is a request from the vfs to use these acls for permission checking. Then fuse could refuse the get acl request for permission checking when the daemon doesn't have FUSE_POSIX_ACL set in the same get acl method. This would also help Overlayfs and allow us to remove the second method for it as well. But since that change is more invasive as we need to update the get acl inode operation for multiple filesystems we should not do this as a fix for v6.2. Instead we will do this for the v6.3 merge window. Fwiw, since posix acls are now always correctly translated in the new posix acl api we could also allow them to be used for daemons without FUSE_POSIX_ACL that are not mounted on the host. But this is behavioral change and again if dones should be done for v6.3. For now, let's just restore the original behavior. A nice side-effect of this change is that for fuse daemons with and without FUSE_POSIX_ACL the same code is used for posix acls in a backwards compatible way. This also means we can remove the legacy xattr handlers completely. We've also added comments to explain the expected behavior for daemons without FUSE_POSIX_ACL into the code. Fixes: 318e66856dde ("xattr: use posix acl api") Signed-off-by: Seth Forshee (Digital Ocean) <sforshee@kernel.org> Reviewed-by: Miklos Szeredi <mszeredi@redhat.com> Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
* fuse: retire block-device-based superblock on force unmountDaniil Lunev2022-07-271-2/+8
| | | | | | | | | | | | | | | | Force unmount of FUSE severes the connection with the user space, even if there are still open files. Subsequent remount tries to re-use the superblock held by the open files, which is meaningless in the FUSE case after disconnect - reused super block doesn't have userspace counterpart attached to it and is incapable of doing any IO. This patch adds the functionality only for the block-device-based supers, since the primary use case of the feature is to gracefully handle force unmount of external devices, mounted with FUSE. This can be further extended to cover all superblocks, if the need arises. Signed-off-by: Daniil Lunev <dlunev@chromium.org> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* fuse: limit nsecMiklos Szeredi2022-07-211-0/+6
| | | | | | | | Limit nanoseconds to 0..999999999. Fixes: d8a5ba45457e ("[PATCH] FUSE - core") Cc: <stable@vger.kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* fs: allocate inode by using alloc_inode_sb()Muchun Song2022-03-221-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The inode allocation is supposed to use alloc_inode_sb(), so convert kmem_cache_alloc() of all filesystems to alloc_inode_sb(). Link: https://lkml.kernel.org/r/20220228122126.37293-5-songmuchun@bytedance.com Signed-off-by: Muchun Song <songmuchun@bytedance.com> Acked-by: Theodore Ts'o <tytso@mit.edu> [ext4] Acked-by: Roman Gushchin <roman.gushchin@linux.dev> Cc: Alex Shi <alexs@kernel.org> Cc: Anna Schumaker <Anna.Schumaker@Netapp.com> Cc: Chao Yu <chao@kernel.org> Cc: Dave Chinner <david@fromorbit.com> Cc: Fam Zheng <fam.zheng@bytedance.com> Cc: Jaegeuk Kim <jaegeuk@kernel.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kari Argillander <kari.argillander@gmail.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Qi Zheng <zhengqi.arch@bytedance.com> Cc: Shakeel Butt <shakeelb@google.com> Cc: Trond Myklebust <trond.myklebust@hammerspace.com> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Wei Yang <richard.weiyang@gmail.com> Cc: Xiongchun Duan <duanxiongchun@bytedance.com> Cc: Yang Shi <shy828301@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* fuse: move FUSE_SUPER_MAGIC definition to magic.hJeff Layton2022-02-211-2/+1
| | | | | | | ...to help userland apps that need to identify FUSE mounts. Signed-off-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* fuse: mark inode DONT_CACHE when per inode DAX hint changesJeffle Xu2021-12-141-0/+3
| | | | | | | | | | | | | | | | | | | | When the per inode DAX hint changes while the file is still *opened*, it is quite complicated and maybe fragile to dynamically change the DAX state. Hence mark the inode and corresponding dentries as DONE_CACHE once the per inode DAX hint changes, so that the inode instance will be evicted and freed as soon as possible once the file is closed and the last reference to the inode is put. And then when the file gets reopened next time, the new instantiated inode will reflect the new DAX state. In summary, when the per inode DAX hint changes for an *opened* file, the DAX state of the file won't be updated until this file is closed and reopened later. Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com> Reviewed-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* fuse: negotiate per inode DAX in FUSE_INITJeffle Xu2021-12-141-4/+9
| | | | | | | | | | | | | | Among the FUSE_INIT phase, client shall advertise per inode DAX if it's mounted with "dax=inode". Then server is aware that client is in per inode DAX mode, and will construct per-inode DAX attribute accordingly. Server shall also advertise support for per inode DAX. If server doesn't support it while client is mounted with "dax=inode", client will silently fallback to "dax=never" since "dax=inode" is advisory only. Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com> Reviewed-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* fuse: enable per inode DAXJeffle Xu2021-12-141-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | DAX may be limited in some specific situation. When the number of usable DAX windows is under watermark, the recalim routine will be triggered to reclaim some DAX windows. It may have a negative impact on the performance, since some processes may need to wait for DAX windows to be recalimed and reused then. To mitigate the performance degradation, the overall DAX window need to be expanded larger. However, simply expanding the DAX window may not be a good deal in some scenario. To maintain one DAX window chunk (i.e., 2MB in size), 32KB (512 * 64 bytes) memory footprint will be consumed for page descriptors inside guest, which is greater than the memory footprint if it uses guest page cache when DAX disabled. Thus it'd better disable DAX for those files smaller than 32KB, to reduce the demand for DAX window and thus avoid the unworthy memory overhead. Per inode DAX feature is introduced to address this issue, by offering a finer grained control for dax to users, trying to achieve a balance between performance and memory overhead. The FUSE_ATTR_DAX flag in FUSE_LOOKUP reply is used to indicate whether DAX should be enabled or not for corresponding file. Currently the state whether DAX is enabled or not for the file is initialized only when inode is instantiated. Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com> Reviewed-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* fuse: make DAX mount option a tri-stateJeffle Xu2021-12-141-3/+7
| | | | | | | | | | | | | | | | | | | | | | We add 'always', 'never', and 'inode' (default). '-o dax' continues to operate the same which is equivalent to 'always'. The following behavior is consistent with that on ext4/xfs: - The default behavior (when neither '-o dax' nor '-o dax=always|never|inode' option is specified) is equal to 'inode' mode, while 'dax=inode' won't be printed among the mount option list. - The 'inode' mode is only advisory. It will silently fallback to 'never' mode if fuse server doesn't support that. Also noted that by the time of this commit, 'inode' mode is actually equal to 'always' mode, before the per inode DAX flag is introduced in the following patch. Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com> Reviewed-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* fuse: send security context of inode on fileVivek Goyal2021-11-251-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When a new inode is created, send its security context to server along with creation request (FUSE_CREAT, FUSE_MKNOD, FUSE_MKDIR and FUSE_SYMLINK). This gives server an opportunity to create new file and set security context (possibly atomically). In all the configurations it might not be possible to set context atomically. Like nfs and ceph, use security_dentry_init_security() to dermine security context of inode and send it with create, mkdir, mknod, and symlink requests. Following is the information sent to server. fuse_sectx_header, fuse_secctx, xattr_name, security_context - struct fuse_secctx_header This contains total number of security contexts being sent and total size of all the security contexts (including size of fuse_secctx_header). - struct fuse_secctx This contains size of security context which follows this structure. There is one fuse_secctx instance per security context. - xattr name string This string represents name of xattr which should be used while setting security context. - security context This is the actual security context whose size is specified in fuse_secctx struct. Also add the FUSE_SECURITY_CTX flag for the `flags` field of the fuse_init_out struct. When this flag is set the kernel will append the security context for a newly created inode to the request (create, mkdir, mknod, and symlink). The server is responsible for ensuring that the inode appears atomically (preferrably) with the requested security context. For example, If the server is using SELinux and backed by a "real" linux file system that supports extended attributes it can write the security context value to /proc/thread-self/attr/fscreate before making the syscall to create the inode. This patch is based on patch from Chirantan Ekbote <chirantan@chromium.org> Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* fuse: extend init flagsMiklos Szeredi2021-11-251-27/+33
| | | | | | | | | | | | | | | | | | | | FUSE_INIT flags are close to running out, so add another 32bits worth of space. Add FUSE_INIT_EXT flag to the old flags field in fuse_init_in. If this flag is set, then fuse_init_in is extended by 48bytes, in which a flags_hi field is allocated to contain the high 32bits of the flags. A flags_hi field is also added to fuse_init_out, allocated out of the remaining unused fields. Known userspace implementations of the fuse protocol have been checked to accept the extended FUSE_INIT request, but this might cause problems with other implementations. If that happens to be the case, the protocol negotiation will have to be extended with an extra initialization request roundtrip. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* fuse: add cache_maskMiklos Szeredi2021-10-281-7/+24
| | | | | | | | | | | | | If writeback_cache is enabled, then the size, mtime and ctime attributes of regular files are always valid in the kernel's cache. They are retrieved from userspace only when the inode is freshly looked up. Add a more generic "cache_mask", that indicates which attributes are currently valid in cache. This patch doesn't change behavior. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* fuse: move reverting attributes to fuse_change_attributes()Miklos Szeredi2021-10-281-0/+13
| | | | | | | | | | | | | In case of writeback_cache fuse_fillattr() would revert the queried attributes to the cached version. Move this to fuse_change_attributes() in order to manage the writeback logic in a central helper. This will be necessary for patches that follow. Only fuse_do_getattr() -> fuse_fillattr() uses the attributes after calling fuse_change_attributes(), so this should not change behavior. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* fuse: simplify local variables holding writeback cache stateMiklos Szeredi2021-10-281-2/+2
| | | | | | | | | There are two instances of "bool is_wb = fc->writeback_cache" where the actual use mostly involves checking "is_wb && S_ISREG(inode->i_mode)". Clean up these cases by storing the second condition in the local variable. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* fuse: make sure reclaim doesn't write the inodeMiklos Szeredi2021-10-221-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | In writeback cache mode mtime/ctime updates are cached, and flushed to the server using the ->write_inode() callback. Closing the file will result in a dirty inode being immediately written, but in other cases the inode can remain dirty after all references are dropped. This result in the inode being written back from reclaim, which can deadlock on a regular allocation while the request is being served. The usual mechanisms (GFP_NOFS/PF_MEMALLOC*) don't work for FUSE, because serving a request involves unrelated userspace process(es). Instead do the same as for dirty pages: make sure the inode is written before the last reference is gone. - fallocate(2)/copy_file_range(2): these call file_update_time() or file_modified(), so flush the inode before returning from the call - unlink(2), link(2) and rename(2): these call fuse_update_ctime(), so flush the ctime directly from this helper Reported-by: chenguanyou <chenguanyou@xiaomi.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* fuse: clean up error exits in fuse_fill_super()Miklos Szeredi2021-10-211-6/+2
| | | | | | | Instead of "goto err", return error directly, since there's no error cleanup to do now. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* fuse: always initialize sb->s_fs_infoMiklos Szeredi2021-10-211-25/+25
| | | | | | | | | | | | | | | | | | | Syzkaller reports a null pointer dereference in fuse_test_super() that is caused by sb->s_fs_info being NULL. This is due to the fact that fuse_fill_super() is initializing s_fs_info, which is too late, it's already on the fs_supers list. The initialization needs to be done in sget_fc() with the sb_lock held. Move allocation of fuse_mount and fuse_conn from fuse_fill_super() into fuse_get_tree(). After this ->kill_sb() will always be called with non-NULL ->s_fs_info, hence fuse_mount_destroy() can drop the test for non-NULL "fm". Reported-by: syzbot+74a15f02ccb51f398601@syzkaller.appspotmail.com Fixes: 5d5b74aa9c76 ("fuse: allow sharing existing sb") Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* fuse: clean up fuse_mount destructionMiklos Szeredi2021-10-211-12/+5
| | | | | | | | | | | | 1. call fuse_mount_destroy() for open coded variants 2. before deactivate_locked_super() don't need fuse_mount destruction since that will now be done (if ->s_fs_info is not cleared) 3. rearrange fuse_mount setup in fuse_get_tree_submount() so that the regular pattern can be used Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* fuse: get rid of fuse_put_super()Miklos Szeredi2021-10-211-9/+11
| | | | | | | | | | | | | | | | The ->put_super callback is called from generic_shutdown_super() in case of a fully initialized sb. This is called from kill_***_super(), which is called from ->kill_sb instances. Fuse uses ->put_super to destroy the fs specific fuse_mount and drop the reference to the fuse_conn, while it does the same on each error case during sb setup. This patch moves the destruction from fuse_put_super() to fuse_mount_destroy(), called at the end of all ->kill_sb instances. A follup patch will clean up the error paths. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* fuse: check s_root when destroying sbMiklos Szeredi2021-10-211-1/+1
| | | | | | | | | | Checking "fm" works because currently sb->s_fs_info is cleared on error paths; however, sb->s_root is what generic_shutdown_super() checks to determine whether the sb was fully initialized or not. This change will allow cleanup of sb setup error paths. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* Merge tag 'fuse-update-5.15' of ↵Linus Torvalds2021-09-071-55/+148
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse Pull fuse updates from Miklos Szeredi: - Allow mounting an active fuse device. Previously the fuse device would always be mounted during initialization, and sharing a fuse superblock was only possible through mount or namespace cloning - Fix data flushing in syncfs (virtiofs only) - Fix data flushing in copy_file_range() - Fix a possible deadlock in atomic O_TRUNC - Misc fixes and cleanups * tag 'fuse-update-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse: fuse: remove unused arg in fuse_write_file_get() fuse: wait for writepages in syncfs fuse: flush extending writes fuse: truncate pagecache on atomic_o_trunc fuse: allow sharing existing sb fuse: move fget() to fuse_get_tree() fuse: move option checking into fuse_fill_super() fuse: name fs_context consistently fuse: fix use after free in fuse_read_interrupt()
| * fuse: wait for writepages in syncfsMiklos Szeredi2021-09-061-0/+60
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In case of fuse the MM subsystem doesn't guarantee that page writeback completes by the time ->sync_fs() is called. This is because fuse completes page writeback immediately to prevent DoS of memory reclaim by the userspace file server. This means that fuse itself must ensure that writes are synced before sending the SYNCFS request to the server. Introduce sync buckets, that hold a counter for the number of outstanding write requests. On syncfs replace the current bucket with a new one and wait until the old bucket's counter goes down to zero. It is possible to have multiple syncfs calls in parallel, in which case there could be more than one waited-on buckets. Descendant buckets must not complete until the parent completes. Add a count to the child (new) bucket until the (parent) old bucket completes. Use RCU protection to dereference the current bucket and to wake up an emptied bucket. Use fc->lock to protect against parallel assignments to the current bucket. This leaves just the counter to be a possible scalability issue. The fc->num_waiting counter has a similar issue, so both should be addressed at the same time. Reported-by: Amir Goldstein <amir73il@gmail.com> Fixes: 2d82ab251ef0 ("virtiofs: propagate sync() to file server") Cc: <stable@vger.kernel.org> # v5.14 Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
| * fuse: allow sharing existing sbMiklos Szeredi2021-08-051-1/+37
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make it possible to create a new mount from a already working server. Here's a detailed description of the problem from Jakob: "The background for this question is occasional problems we see with our fuse filesystem [1] and mount namespaces. On a usual client, we have system-wide, autofs managed mountpoints. When a new mount namespace is created (which can be done unprivileged in combination with user namespaces), it can happen that a mountpoint is used inside the new namespace but idle in the root mount namespace. So autofs unmounts the parent, system-wide mountpoint. But the fuse module stays active and still serves mountpoint in the child mount namespace. Because the fuse daemon also blocks other system wide resources corresponding to the mountpoint, this situation effectively prevents new mounts until the child mount namespaces closes. [1] https://github.com/cvmfs/cvmfs" Reported-by: Jakob Blomer <jblomer@cern.ch> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
| * fuse: move fget() to fuse_get_tree()Miklos Szeredi2021-08-051-23/+21
| | | | | | | | | | | | | | | | | | | | | | | | Affected call chains: fuse_get_tree -> get_tree_(bdev|nodev) -> fuse_fill_super Needed for following patch. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
| * fuse: move option checking into fuse_fill_super()Miklos Szeredi2021-08-041-7/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | Checking whether the "fd=", "rootmode=", "user_id=" and "group_id=" mount options are present can be moved from fuse_get_tree() into fuse_fill_super() where the value of the options are consumed. This relaxes semantics of reusing a fuse blockdev mount using the device name. Before this patch presence of these options were enforced but values ignored, after this patch these options are completely ignored in this case. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
| * fuse: name fs_context consistentlyMiklos Szeredi2021-08-041-30/+30
| | | | | | | | | | | | | | | | | | Naming convention under fs/fuse/: struct fuse_conn *fc; struct fs_context *fsc; Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* | fuse: Convert to using invalidate_lockJan Kara2021-07-131-1/+0
|/ | | | | | | | | | | Use invalidate_lock instead of fuse's private i_mmap_sem. The intended purpose is exactly the same. By this conversion we fix a long standing race between hole punching and read(2) / readahead(2) paths that can lead to stale page cache contents. CC: Miklos Szeredi <miklos@szeredi.hu> Reviewed-by: Miklos Szeredi <mszeredi@redhat.com> Signed-off-by: Jan Kara <jack@suse.cz>
* fuse: fix illegal access to inode with reused nodeidAmir Goldstein2021-06-221-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | Server responds to LOOKUP and other ops (READDIRPLUS/CREATE/MKNOD/...) with ourarg containing nodeid and generation. If a fuse inode is found in inode cache with the same nodeid but different generation, the existing fuse inode should be unhashed and marked "bad" and a new inode with the new generation should be hashed instead. This can happen, for example, with passhrough fuse filesystem that returns the real filesystem ino/generation on lookup and where real inode numbers can get recycled due to real files being unlinked not via the fuse passthrough filesystem. With current code, this situation will not be detected and an old fuse dentry that used to point to an older generation real inode, can be used to access a completely new inode, which should be accessed only via the new dentry. Note that because the FORGET message carries the nodeid w/o generation, the server should wait to get FORGET counts for the nlookup counts of the old and reused inodes combined, before it can free the resources associated to that nodeid. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* fuse: Make fuse_fill_super_submount() staticGreg Kurz2021-06-221-2/+2
| | | | | | | | | | | This function used to be called from fuse_dentry_automount(). This code was moved to fuse_get_tree_submount() in the same file since then. It is unlikely there will ever be another user. No need to be extern in this case. Signed-off-by: Greg Kurz <groug@kaod.org> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* fuse: Call vfs_get_tree() for submountsGreg Kurz2021-06-221-0/+36
| | | | | | | | | | | | | | We recently fixed an infinite loop by setting the SB_BORN flag on submounts along with the write barrier needed by super_cache_count(). This is the job of vfs_get_tree() and FUSE shouldn't have to care about the barrier at all. Split out some code from fuse_dentry_automount() to the dedicated fuse_get_tree_submount() handler for submounts and call vfs_get_tree(). Signed-off-by: Greg Kurz <groug@kaod.org> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* fuse: add dedicated filesystem context ops for submountsGreg Kurz2021-06-221-0/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | The creation of a submount is open-coded in fuse_dentry_automount(). This brings a lot of complexity and we recently had to fix bugs because we weren't setting SB_BORN or because we were unlocking sb->s_umount before sb was fully configured. Most of these could have been avoided by using the mount API instead of open-coding. Basically, this means coming up with a proper ->get_tree() implementation for submounts and call vfs_get_tree(), or better fc_mount(). The creation of the superblock for submounts is quite different from the root mount. Especially, it doesn't require to allocate a FUSE filesystem context, nor to parse parameters. Introduce a dedicated context ops for submounts to make this clear. This is just a placeholder for now, fuse_get_tree_submount() will be populated in a subsequent patch. Only visible change is that we stop allocating/freeing a useless FUSE filesystem context with submounts. Signed-off-by: Greg Kurz <groug@kaod.org> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* virtiofs: propagate sync() to file serverGreg Kurz2021-06-221-0/+40
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Even if POSIX doesn't mandate it, linux users legitimately expect sync() to flush all data and metadata to physical storage when it is located on the same system. This isn't happening with virtiofs though: sync() inside the guest returns right away even though data still needs to be flushed from the host page cache. This is easily demonstrated by doing the following in the guest: $ dd if=/dev/zero of=/mnt/foo bs=1M count=5K ; strace -T -e sync sync 5120+0 records in 5120+0 records out 5368709120 bytes (5.4 GB, 5.0 GiB) copied, 5.22224 s, 1.0 GB/s sync() = 0 <0.024068> and start the following in the host when the 'dd' command completes in the guest: $ strace -T -e fsync /usr/bin/sync virtiofs/foo fsync(3) = 0 <10.371640> There are no good reasons not to honor the expected behavior of sync() actually: it gives an unrealistic impression that virtiofs is super fast and that data has safely landed on HW, which isn't the case obviously. Implement a ->sync_fs() superblock operation that sends a new FUSE_SYNCFS request type for this purpose. Provision a 64-bit placeholder for possible future extensions. Since the file server cannot handle the wait == 0 case, we skip it to avoid a gratuitous roundtrip. Note that this is per-superblock: a FUSE_SYNCFS is send for the root mount and for each submount. Like with FUSE_FSYNC and FUSE_FSYNCDIR, lack of support for FUSE_SYNCFS in the file server is treated as permanent success. This ensures compatibility with older file servers: the client will get the current behavior of sync() not being propagated to the file server. Note that such an operation allows the file server to DoS sync(). Since a typical FUSE file server is an untrusted piece of software running in userspace, this is disabled by default. Only enable it with virtiofs for now since virtiofsd is supposedly trusted by the guest kernel. Reported-by: Robert Krawitz <rlk@redhat.com> Signed-off-by: Greg Kurz <groug@kaod.org> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* Merge branch 'work.misc' of ↵Linus Torvalds2021-05-021-2/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull misc vfs updates from Al Viro: "Assorted stuff all over the place" * 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: useful constants: struct qstr for ".." hostfs_open(): don't open-code file_dentry() whack-a-mole: kill strlen_user() (again) autofs: should_expire() argument is guaranteed to be positive apparmor:match_mn() - constify devpath argument buffer: a small optimization in grow_buffers get rid of autofs_getpath() constify dentry argument of dentry_path()/dentry_path_raw()
| * useful constants: struct qstr for ".."Al Viro2021-04-151-2/+1
| | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | Merge tag 'fuse-update-5.13' of ↵Linus Torvalds2021-04-301-2/+5
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse Pull fuse updates from Miklos Szeredi: - Fix a page locking bug in write (introduced in 2.6.26) - Allow sgid bit to be killed in setacl() - Miscellaneous fixes and cleanups * tag 'fuse-update-5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse: cuse: simplify refcount cuse: prevent clone virtiofs: fix userns virtiofs: remove useless function virtiofs: split requests that exceed virtqueue size virtiofs: fix memory leak in virtio_fs_probe() fuse: invalidate attrs when page writeback completes fuse: add a flag FUSE_SETXATTR_ACL_KILL_SGID to kill SGID fuse: extend FUSE_SETXATTR request fuse: fix matching of FUSE_DEV_IOC_CLONE command fuse: fix a typo fuse: don't zero pages twice fuse: fix typo for fuse_conn.max_pages comment fuse: fix write deadlock
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-14 09:38:36 +0000