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2019-05-21treewide: Add SPDX license identifier - Makefile/KconfigThomas Gleixner2-0/+2
Add SPDX license identifiers to all Make/Kconfig files which: - Have no license information of any form These files fall under the project license, GPL v2 only. The resulting SPDX license identifier is: GPL-2.0-only Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-14Merge tag 'fuse-update-5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuseLinus Torvalds6-29/+72
Pull fuse update from Miklos Szeredi: "Add more caching controls for userspace filesystems to use, as well as bug fixes and cleanups" * tag 'fuse-update-5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse: fuse: clean up fuse_alloc_inode fuse: Add ioctl flag for x32 compat ioctl fuse: Convert fusectl to use the new mount API fuse: fix changelog entry for protocol 7.9 fuse: fix changelog entry for protocol 7.12 fuse: document fuse_fsync_in.fsync_flags fuse: Add FOPEN_STREAM to use stream_open() fuse: require /dev/fuse reads to have enough buffer capacity fuse: retrieve: cap requested size to negotiated max_write fuse: allow filesystems to have precise control over data cache fuse: convert printk -> pr_* fuse: honor RLIMIT_FSIZE in fuse_file_fallocate fuse: fix writepages on 32bit
2019-05-08fuse: clean up fuse_alloc_inodezhangliguang1-6/+4
This patch cleans up fuse_alloc_inode function, just simply the code, no logic change. Signed-off-by: zhangliguang <zhangliguang@linux.alibaba.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-05-07Merge branch 'work.icache' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfsLinus Torvalds1-14/+10
Pull vfs inode freeing updates from Al Viro: "Introduction of separate method for RCU-delayed part of ->destroy_inode() (if any). Pretty much as posted, except that destroy_inode() stashes ->free_inode into the victim (anon-unioned with ->i_fops) before scheduling i_callback() and the last two patches (sockfs conversion and folding struct socket_wq into struct socket) are excluded - that pair should go through netdev once davem reopens his tree" * 'work.icache' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (58 commits) orangefs: make use of ->free_inode() shmem: make use of ->free_inode() hugetlb: make use of ->free_inode() overlayfs: make use of ->free_inode() jfs: switch to ->free_inode() fuse: switch to ->free_inode() ext4: make use of ->free_inode() ecryptfs: make use of ->free_inode() ceph: use ->free_inode() btrfs: use ->free_inode() afs: switch to use of ->free_inode() dax: make use of ->free_inode() ntfs: switch to ->free_inode() securityfs: switch to ->free_inode() apparmor: switch to ->free_inode() rpcpipe: switch to ->free_inode() bpf: switch to ->free_inode() mqueue: switch to ->free_inode() ufs: switch to ->free_inode() coda: switch to ->free_inode() ...
2019-05-01fuse: switch to ->free_inode()Al Viro1-14/+10
fuse_destroy_inode() is gone - sanity checks that need the stack trace of the caller get moved into ->evict_inode(), the rest joins the RCU-delayed part which becomes ->free_inode(). While we are at it, don't just pass the address of what happens to be the first member of structure to kmem_cache_free() - get_fuse_inode() is there for purpose and it gives the proper container_of() use. No behaviour change, but verifying correctness is easier that way. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-04-24fuse: Add ioctl flag for x32 compat ioctlIan Abbott1-1/+6
Currently, a CUSE server running on a 64-bit kernel can tell when an ioctl request comes from a process running a 32-bit ABI, but cannot tell whether the requesting process is using legacy IA32 emulation or x32 ABI. In particular, the server does not know the size of the client process's `time_t` type. For 64-bit kernels, the `FUSE_IOCTL_COMPAT` and `FUSE_IOCTL_32BIT` flags are currently set in the ioctl input request (`struct fuse_ioctl_in` member `flags`) for a 32-bit requesting process. This patch defines a new flag `FUSE_IOCTL_COMPAT_X32` and sets it if the 32-bit requesting process is using the x32 ABI. This allows the server process to distinguish between requests coming from client processes using IA32 emulation or the x32 ABI and so infer the size of the client process's `time_t` type and any other IA32/x32 differences. Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-04-24fuse: Convert fusectl to use the new mount APIDavid Howells1-5/+15
Convert the fusectl filesystem to the new internal mount API as the old one will be obsoleted and removed. This allows greater flexibility in communication of mount parameters between userspace, the VFS and the filesystem. See Documentation/filesystems/mount_api.txt for more information. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-04-24fuse: document fuse_fsync_in.fsync_flagsAlan Somers1-1/+1
The FUSE_FSYNC_DATASYNC flag was introduced by commit b6aeadeda22a ("[PATCH] FUSE - file operations") as a magic number. No new values have been added to fsync_flags since. Signed-off-by: Alan Somers <asomers@FreeBSD.org> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-04-24fuse: Add FOPEN_STREAM to use stream_open()Kirill Smelkov1-1/+3
Starting from commit 9c225f2655e3 ("vfs: atomic f_pos accesses as per POSIX") files opened even via nonseekable_open gate read and write via lock and do not allow them to be run simultaneously. This can create read vs write deadlock if a filesystem is trying to implement a socket-like file which is intended to be simultaneously used for both read and write from filesystem client. See commit 10dce8af3422 ("fs: stream_open - opener for stream-like files so that read and write can run simultaneously without deadlock") for details and e.g. commit 581d21a2d02a ("xenbus: fix deadlock on writes to /proc/xen/xenbus") for a similar deadlock example on /proc/xen/xenbus. To avoid such deadlock it was tempting to adjust fuse_finish_open to use stream_open instead of nonseekable_open on just FOPEN_NONSEEKABLE flags, but grepping through Debian codesearch shows users of FOPEN_NONSEEKABLE, and in particular GVFS which actually uses offset in its read and write handlers https://codesearch.debian.net/search?q=-%3Enonseekable+%3D https://gitlab.gnome.org/GNOME/gvfs/blob/1.40.0-6-gcbc54396/client/gvfsfusedaemon.c#L1080 https://gitlab.gnome.org/GNOME/gvfs/blob/1.40.0-6-gcbc54396/client/gvfsfusedaemon.c#L1247-1346 https://gitlab.gnome.org/GNOME/gvfs/blob/1.40.0-6-gcbc54396/client/gvfsfusedaemon.c#L1399-1481 so if we would do such a change it will break a real user. Add another flag (FOPEN_STREAM) for filesystem servers to indicate that the opened handler is having stream-like semantics; does not use file position and thus the kernel is free to issue simultaneous read and write request on opened file handle. This patch together with stream_open() should be added to stable kernels starting from v3.14+. This will allow to patch OSSPD and other FUSE filesystems that provide stream-like files to return FOPEN_STREAM | FOPEN_NONSEEKABLE in open handler and this way avoid the deadlock on all kernel versions. This should work because fuse_finish_open ignores unknown open flags returned from a filesystem and so passing FOPEN_STREAM to a kernel that is not aware of this flag cannot hurt. In turn the kernel that is not aware of FOPEN_STREAM will be < v3.14 where just FOPEN_NONSEEKABLE is sufficient to implement streams without read vs write deadlock. Cc: stable@vger.kernel.org # v3.14+ Signed-off-by: Kirill Smelkov <kirr@nexedi.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-04-24fuse: require /dev/fuse reads to have enough buffer capacityKirill Smelkov1-0/+10
A FUSE filesystem server queues /dev/fuse sys_read calls to get filesystem requests to handle. It does not know in advance what would be that request as it can be anything that client issues - LOOKUP, READ, WRITE, ... Many requests are short and retrieve data from the filesystem. However WRITE and NOTIFY_REPLY write data into filesystem. Before getting into operation phase, FUSE filesystem server and kernel client negotiate what should be the maximum write size the client will ever issue. After negotiation the contract in between server/client is that the filesystem server then should queue /dev/fuse sys_read calls with enough buffer capacity to receive any client request - WRITE in particular, while FUSE client should not, in particular, send WRITE requests with > negotiated max_write payload. FUSE client in kernel and libfuse historically reserve 4K for request header. This way the contract is that filesystem server should queue sys_reads with 4K+max_write buffer. If the filesystem server does not follow this contract, what can happen is that fuse_dev_do_read will see that request size is > buffer size, and then it will return EIO to client who issued the request but won't indicate in any way that there is a problem to filesystem server. This can be hard to diagnose because for some requests, e.g. for NOTIFY_REPLY which mimics WRITE, there is no client thread that is waiting for request completion and that EIO goes nowhere, while on filesystem server side things look like the kernel is not replying back after successful NOTIFY_RETRIEVE request made by the server. We can make the problem easy to diagnose if we indicate via error return to filesystem server when it is violating the contract. This should not practically cause problems because if a filesystem server is using shorter buffer, writes to it were already very likely to cause EIO, and if the filesystem is read-only it should be too following FUSE_MIN_READ_BUFFER minimum buffer size. Please see [1] for context where the problem of stuck filesystem was hit for real (because kernel client was incorrectly sending more than max_write data with NOTIFY_REPLY; see also previous patch), how the situation was traced and for more involving patch that did not make it into the tree. [1] https://marc.info/?l=linux-fsdevel&m=155057023600853&w=2 Signed-off-by: Kirill Smelkov <kirr@nexedi.com> Cc: Han-Wen Nienhuys <hanwen@google.com> Cc: Jakob Unterwurzacher <jakobunt@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-04-24fuse: retrieve: cap requested size to negotiated max_writeKirill Smelkov1-1/+1
FUSE filesystem server and kernel client negotiate during initialization phase, what should be the maximum write size the client will ever issue. Correspondingly the filesystem server then queues sys_read calls to read requests with buffer capacity large enough to carry request header + that max_write bytes. A filesystem server is free to set its max_write in anywhere in the range between [1*page, fc->max_pages*page]. In particular go-fuse[2] sets max_write by default as 64K, wheres default fc->max_pages corresponds to 128K. Libfuse also allows users to configure max_write, but by default presets it to possible maximum. If max_write is < fc->max_pages*page, and in NOTIFY_RETRIEVE handler we allow to retrieve more than max_write bytes, corresponding prepared NOTIFY_REPLY will be thrown away by fuse_dev_do_read, because the filesystem server, in full correspondence with server/client contract, will be only queuing sys_read with ~max_write buffer capacity, and fuse_dev_do_read throws away requests that cannot fit into server request buffer. In turn the filesystem server could get stuck waiting indefinitely for NOTIFY_REPLY since NOTIFY_RETRIEVE handler returned OK which is understood by clients as that NOTIFY_REPLY was queued and will be sent back. Cap requested size to negotiate max_write to avoid the problem. This aligns with the way NOTIFY_RETRIEVE handler works, which already unconditionally caps requested retrieve size to fuse_conn->max_pages. This way it should not hurt NOTIFY_RETRIEVE semantic if we return less data than was originally requested. Please see [1] for context where the problem of stuck filesystem was hit for real, how the situation was traced and for more involving patch that did not make it into the tree. [1] https://marc.info/?l=linux-fsdevel&m=155057023600853&w=2 [2] https://github.com/hanwen/go-fuse Signed-off-by: Kirill Smelkov <kirr@nexedi.com> Cc: Han-Wen Nienhuys <hanwen@google.com> Cc: Jakob Unterwurzacher <jakobunt@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-04-24fuse: allow filesystems to have precise control over data cacheKirill Smelkov2-2/+8
On networked filesystems file data can be changed externally. FUSE provides notification messages for filesystem to inform kernel that metadata or data region of a file needs to be invalidated in local page cache. That provides the basis for filesystem implementations to invalidate kernel cache explicitly based on observed filesystem-specific events. FUSE has also "automatic" invalidation mode(*) when the kernel automatically invalidates data cache of a file if it sees mtime change. It also automatically invalidates whole data cache of a file if it sees file size being changed. The automatic mode has corresponding capability - FUSE_AUTO_INVAL_DATA. However, due to probably historical reason, that capability controls only whether mtime change should be resulting in automatic invalidation or not. A change in file size always results in invalidating whole data cache of a file irregardless of whether FUSE_AUTO_INVAL_DATA was negotiated(+). The filesystem I write[1] represents data arrays stored in networked database as local files suitable for mmap. It is read-only filesystem - changes to data are committed externally via database interfaces and the filesystem only glues data into contiguous file streams suitable for mmap and traditional array processing. The files are big - starting from hundreds gigabytes and more. The files change regularly, and frequently by data being appended to their end. The size of files thus changes frequently. If a file was accessed locally and some part of its data got into page cache, we want that data to stay cached unless there is memory pressure, or unless corresponding part of the file was actually changed. However current FUSE behaviour - when it sees file size change - is to invalidate the whole file. The data cache of the file is thus completely lost even on small size change, and despite that the filesystem server is careful to accurately translate database changes into FUSE invalidation messages to kernel. Let's fix it: if a filesystem, through new FUSE_EXPLICIT_INVAL_DATA capability, indicates to kernel that it is fully responsible for data cache invalidation, then the kernel won't invalidate files data cache on size change and only truncate that cache to new size in case the size decreased. (*) see 72d0d248ca "fuse: add FUSE_AUTO_INVAL_DATA init flag", eed2179efe "fuse: invalidate inode mapping if mtime changes" (+) in writeback mode the kernel does not invalidate data cache on file size change, but neither it allows the filesystem to set the size due to external event (see 8373200b12 "fuse: Trust kernel i_size only") [1] https://lab.nexedi.com/kirr/wendelin.core/blob/a50f1d9f/wcfs/wcfs.go#L20 Signed-off-by: Kirill Smelkov <kirr@nexedi.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-04-24fuse: convert printk -> pr_*Kirill Smelkov4-11/+16
Functions, like pr_err, are a more modern variant of printing compared to printk. They could be used to denoise sources by using needed level in the print function name, and by automatically inserting per-driver / function / ... print prefix as defined by pr_fmt macro. pr_* are also said to be used in Documentation/process/coding-style.rst and more recent code - for example overlayfs - uses them instead of printk. Convert CUSE and FUSE to use the new pr_* functions. CUSE output stays completely unchanged, while FUSE output is amended a bit for "trying to steal weird page" warning - the second line now comes also with "fuse:" prefix. I hope it is ok. Suggested-by: Kirill Tkhai <ktkhai@virtuozzo.com> Signed-off-by: Kirill Smelkov <kirr@nexedi.com> Reviewed-by: Kirill Tkhai <ktkhai@virtuozzo.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-04-24fuse: honor RLIMIT_FSIZE in fuse_file_fallocateLiu Bo1-0/+7
fstests generic/228 reported this failure that fuse fallocate does not honor what 'ulimit -f' has set. This adds the necessary inode_newsize_ok() check. Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com> Fixes: 05ba1f082300 ("fuse: add FALLOCATE operation") Cc: <stable@vger.kernel.org> # v3.5 Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-04-24fuse: fix writepages on 32bitMiklos Szeredi1-1/+1
Writepage requests were cropped to i_size & 0xffffffff, which meant that mmaped writes to any file larger than 4G might be silently discarded. Fix by storing the file size in a properly sized variable (loff_t instead of size_t). Reported-by: Antonio SJ Musumeci <trapexit@spawn.link> Fixes: 6eaf4782eb09 ("fuse: writepages: crop secondary requests") Cc: <stable@vger.kernel.org> # v3.13 Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-04-14Merge branch 'page-refs' (page ref overflow)Linus Torvalds1-6/+6
Merge page ref overflow branch. Jann Horn reported that he can overflow the page ref count with sufficient memory (and a filesystem that is intentionally extremely slow). Admittedly it's not exactly easy. To have more than four billion references to a page requires a minimum of 32GB of kernel memory just for the pointers to the pages, much less any metadata to keep track of those pointers. Jann needed a total of 140GB of memory and a specially crafted filesystem that leaves all reads pending (in order to not ever free the page references and just keep adding more). Still, we have a fairly straightforward way to limit the two obvious user-controllable sources of page references: direct-IO like page references gotten through get_user_pages(), and the splice pipe page duplication. So let's just do that. * branch page-refs: fs: prevent page refcount overflow in pipe_buf_get mm: prevent get_user_pages() from overflowing page refcount mm: add 'try_get_page()' helper function mm: make page ref count overflow check tighter and more explicit
2019-04-14fs: prevent page refcount overflow in pipe_buf_getMatthew Wilcox1-6/+6
Change pipe_buf_get() to return a bool indicating whether it succeeded in raising the refcount of the page (if the thing in the pipe is a page). This removes another mechanism for overflowing the page refcount. All callers converted to handle a failure. Reported-by: Jann Horn <jannh@google.com> Signed-off-by: Matthew Wilcox <willy@infradead.org> Cc: stable@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-03-12Merge tag 'fuse-update-5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuseLinus Torvalds8-259/+321
Pull fuse updates from Miklos Szeredi: "Scalability and performance improvements, as well as minor bug fixes and cleanups" * tag 'fuse-update-5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse: (25 commits) fuse: cache readdir calls if filesystem opts out of opendir fuse: support clients that don't implement 'opendir' fuse: lift bad inode checks into callers fuse: multiplex cached/direct_io file operations fuse add copy_file_range to direct io fops fuse: use iov_iter based generic splice helpers fuse: Switch to using async direct IO for FOPEN_DIRECT_IO fuse: use atomic64_t for khctr fuse: clean up aborted fuse: Protect ff->reserved_req via corresponding fi->lock fuse: Protect fi->nlookup with fi->lock fuse: Introduce fi->lock to protect write related fields fuse: Convert fc->attr_version into atomic64_t fuse: Add fuse_inode argument to fuse_prepare_release() fuse: Verify userspace asks to requeue interrupt that we really sent fuse: Do some refactoring in fuse_dev_do_write() fuse: Wake up req->waitq of only if not background fuse: Optimize request_end() by not taking fiq->waitq.lock fuse: Kill fasync only if interrupt is queued in queue_interrupt() fuse: Remove stale comment in end_requests() ...
2019-03-12mm: refactor readahead defines in mm.hNikolay Borisov1-1/+1
All users of VM_MAX_READAHEAD actually convert it to kbytes and then to pages. Define the macro explicitly as (SZ_128K / PAGE_SIZE). This simplifies the expression in every filesystem. Also rename the macro to VM_READAHEAD_PAGES to properly convey its meaning. Finally remove unused VM_MIN_READAHEAD [akpm@linux-foundation.org: fix fs/io_uring.c, per Stephen] Link: http://lkml.kernel.org/r/20181221144053.24318-1-nborisov@suse.com Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: Matthew Wilcox <willy@infradead.org> Reviewed-by: David Hildenbrand <david@redhat.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Eric Van Hensbergen <ericvh@gmail.com> Cc: Latchesar Ionkov <lucho@ionkov.net> Cc: Dominique Martinet <asmadeus@codewreck.org> Cc: David Howells <dhowells@redhat.com> Cc: Chris Mason <clm@fb.com> Cc: Josef Bacik <josef@toxicpanda.com> Cc: David Sterba <dsterba@suse.com> Cc: Miklos Szeredi <miklos@szeredi.hu> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-02-13fuse: cache readdir calls if filesystem opts out of opendirChad Austin1-1/+2
If a filesystem returns ENOSYS from opendir and thus opts out of opendir and releasedir requests, it almost certainly would also like readdir results cached. Default open_flags to FOPEN_KEEP_CACHE and FOPEN_CACHE_DIR in that case. With this patch, I've measured recursive directory enumeration across large FUSE mounts to be faster than native mounts. Signed-off-by: Chad Austin <chadaustin@fb.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-02-13fuse: support clients that don't implement 'opendir'Chad Austin3-5/+12
Allow filesystems to return ENOSYS from opendir, preventing the kernel from sending opendir and releasedir messages in the future. This avoids userspace transitions when filesystems don't need to keep track of state per directory handle. A new capability flag, FUSE_NO_OPENDIR_SUPPORT, parallels FUSE_NO_OPEN_SUPPORT, indicating the new semantics for returning ENOSYS from opendir. Signed-off-by: Chad Austin <chadaustin@fb.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-02-13fuse: lift bad inode checks into callersMiklos Szeredi1-16/+10
Bad inode checks were done done in various places, and move them into fuse_file_{read|write}_iter(). Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-02-13fuse: multiplex cached/direct_io file operationsMiklos Szeredi1-37/+34
This is cleanup, as well as allowing switching between I/O modes while the file is open in the future. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-02-13fuse add copy_file_range to direct io fopsMiklos Szeredi1-0/+1
Nothing preventing copy_file_range to work on files opened with FOPEN_DIRECT_IO. Fixes: 88bc7d5097a1 ("fuse: add support for copy_file_range()") Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-02-13fuse: use iov_iter based generic splice helpersMiklos Szeredi1-1/+3
The default splice implementation is grossly inefficient and the iter based ones work just fine, so use those instead. I've measured an 8x speedup for splice write (with len = 128k). Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-02-13fuse: Switch to using async direct IO for FOPEN_DIRECT_IOMartin Raiber1-4/+26
Switch to using the async directo IO code path in fuse_direct_read_iter() and fuse_direct_write_iter(). This is especially important in connection with loop devices with direct IO enabled as loop assumes async direct io is actually async. Signed-off-by: Martin Raiber <martin@urbackup.org> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-02-13fuse: use atomic64_t for khctrMiklos Szeredi3-5/+3
...to get rid of one more fc->lock use. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-02-13fuse: clean up abortedMiklos Szeredi5-11/+12
The only caller that needs fc->aborted set is fuse_conn_abort_write(). Setting fc->aborted is now racy (fuse_abort_conn() may already be in progress or finished) but there's no reason to care. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-02-13fuse: Protect ff->reserved_req via corresponding fi->lockKirill Tkhai2-5/+10
This is rather natural action after previous patches, and it just decreases load of fc->lock. Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-02-13fuse: Protect fi->nlookup with fi->lockKirill Tkhai3-6/+6
This continues previous patch and introduces the same protection for nlookup field. Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-02-13fuse: Introduce fi->lock to protect write related fieldsKirill Tkhai4-62/+70
To minimize contention of fc->lock, this patch introduces a new spinlock for protection fuse_inode metadata: fuse_inode: writectr writepages write_files queued_writes attr_version inode: i_size i_nlink i_mtime i_ctime Also, it protects the fields changed in fuse_change_attributes_common() (too many to list). Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-02-13fuse: Convert fc->attr_version into atomic64_tKirill Tkhai4-26/+14
This patch makes fc->attr_version of atomic64_t type, so fc->lock won't be needed to read or modify it anymore. Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-02-13fuse: Add fuse_inode argument to fuse_prepare_release()Kirill Tkhai4-8/+13
Here is preparation for next patches, which introduce new fi->lock for protection of ff->write_entry linked into fi->write_files. This patch just passes new argument to the function. Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-02-13fuse: Verify userspace asks to requeue interrupt that we really sentKirill Tkhai1-3/+10
When queue_interrupt() is called from fuse_dev_do_write(), it came from userspace directly. Userspace may pass any request id, even the request's we have not interrupted (or even background's request). This patch adds sanity check to make kernel safe against that. Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-02-13fuse: Do some refactoring in fuse_dev_do_write()Kirill Tkhai1-25/+23
This is needed for next patch. Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-02-13fuse: Wake up req->waitq of only if not backgroundKirill Tkhai1-1/+4
Currently, we wait on req->waitq in request_wait_answer() function only, and it's never used for background requests. Since wake_up() is not a light-weight macros, instead of this, it unfolds in really called function, which makes locking operations taking some cpu cycles, let's avoid its call for the case we definitely know it's completely useless. Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-02-13fuse: Optimize request_end() by not taking fiq->waitq.lockKirill Tkhai1-8/+20
We take global fiq->waitq.lock every time, when we are in this function, but interrupted requests are just small subset of all requests. This patch optimizes request_end() and makes it to take the lock when it's really needed. queue_interrupt() needs small change for that. After req is linked to interrupt list, we do smp_mb() and check for FR_FINISHED again. In case of FR_FINISHED bit has appeared, we remove req and leave the function: Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-02-13fuse: Kill fasync only if interrupt is queued in queue_interrupt()Kirill Tkhai1-1/+1
We should sent signal only in case of interrupt is really queued. Not a real problem, but this makes the code clearer and intuitive. Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-02-13fuse: Remove stale comment in end_requests()Kirill Tkhai1-5/+1
Function end_requests() does not take fc->lock. Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-02-13fuse: Replace page without copying in fuse_writepage_in_flight()Kirill Tkhai1-1/+1
It looks like we can optimize page replacement and avoid copying by simple updating the request's page. [SzM: swap with new request's tmp page to avoid use after free.] Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-02-13fuse: fix leaked aux requestsMiklos Szeredi1-0/+10
Auxiliary requests chained on req->misc.write.next may be leaked on truncate. Free these as well if the parent request was truncated off. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-02-13fuse: only reuse auxiliary request in fuse_writepage_in_flight()Miklos Szeredi1-6/+7
Don't reuse the queued request, even if it only contains a single page. This is needed because previous locking changes (spliting out fiq->waitq.lock from fc->lock) broke the assumption that request will remain in FR_PENDING at least until the new page contents are copied. This fix removes a slight optimization for a rare corner case, so we really shoudln't care. Reported-by: Kirill Tkhai <ktkhai@virtuozzo.com> Fixes: fd22d62ed0c3 ("fuse: no fc->lock for iqueue parts") Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-02-13fuse: clean up fuse_writepage_in_flight()Miklos Szeredi1-16/+24
Restructure the function to better separate the locked and the unlocked parts. Use the "old_req" local variable to mean only the queued request, and not any auxiliary requests added onto its misc.write.next list. These changes are in preparation for the following patch. Also turn BUG_ON instances into WARN_ON and add a header comment explaining what the function does. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-02-13fuse: extract fuse_find_writeback() helperMiklos Szeredi1-27/+25
Call this from fuse_range_is_writeback() and fuse_writepage_in_flight(). Turn a BUG_ON() into a WARN_ON() in the process. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-01-16fuse: decrement NR_WRITEBACK_TEMP on the right pageMiklos Szeredi1-1/+1
NR_WRITEBACK_TEMP is accounted on the temporary page in the request, not the page cache page. Fixes: 8b284dc47291 ("fuse: writepages: handle same page rewrites") Cc: <stable@vger.kernel.org> # v3.13 Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-01-16fuse: call pipe_buf_release() under pipe lockJann Horn1-0/+2
Some of the pipe_buf_release() handlers seem to assume that the pipe is locked - in particular, anon_pipe_buf_release() accesses pipe->tmp_page without taking any extra locks. From a glance through the callers of pipe_buf_release(), it looks like FUSE is the only one that calls pipe_buf_release() without having the pipe locked. This bug should only lead to a memory leak, nothing terrible. Fixes: dd3bb14f44a6 ("fuse: support splice() writing to fuse device") Cc: stable@vger.kernel.org Signed-off-by: Jann Horn <jannh@google.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-01-16cuse: fix ioctlMiklos Szeredi1-1/+1
cuse_process_init_reply() doesn't initialize fc->max_pages and thus all cuse bases ioctls fail with ENOMEM. Reported-by: Andreas Steinmetz <ast@domdv.de> Fixes: 5da784cce430 ("fuse: add max_pages to init_out") Cc: <stable@vger.kernel.org> # v4.20 Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-01-16fuse: handle zero sized retrieve correctlyMiklos Szeredi1-1/+1
Dereferencing req->page_descs[0] will Oops if req->max_pages is zero. Reported-by: syzbot+c1e36d30ee3416289cc0@syzkaller.appspotmail.com Tested-by: syzbot+c1e36d30ee3416289cc0@syzkaller.appspotmail.com Fixes: b2430d7567a3 ("fuse: add per-page descriptor <offset, length> to fuse_req") Cc: <stable@vger.kernel.org> # v3.9 Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2018-12-28mm: convert totalram_pages and totalhigh_pages variables to atomicArun KS1-1/+1
totalram_pages and totalhigh_pages are made static inline function. Main motivation was that managed_page_count_lock handling was complicating things. It was discussed in length here, https://lore.kernel.org/patchwork/patch/995739/#1181785 So it seemes better to remove the lock and convert variables to atomic, with preventing poteintial store-to-read tearing as a bonus. [akpm@linux-foundation.org: coding style fixes] Link: http://lkml.kernel.org/r/1542090790-21750-4-git-send-email-arunks@codeaurora.org Signed-off-by: Arun KS <arunks@codeaurora.org> Suggested-by: Michal Hocko <mhocko@suse.com> Suggested-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Reviewed-by: Pavel Tatashin <pasha.tatashin@soleen.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-12-11fuse: continue to send FUSE_RELEASEDIR when FUSE_OPEN returns ENOSYSChad Austin3-12/+13
When FUSE_OPEN returns ENOSYS, the no_open bit is set on the connection. Because the FUSE_RELEASE and FUSE_RELEASEDIR paths share code, this incorrectly caused the FUSE_RELEASEDIR request to be dropped and never sent to userspace. Pass an isdir bool to distinguish between FUSE_RELEASE and FUSE_RELEASEDIR inside of fuse_file_put. Fixes: 7678ac50615d ("fuse: support clients that don't implement 'open'") Cc: <stable@vger.kernel.org> # v3.14 Signed-off-by: Chad Austin <chadaustin@fb.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>