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2020-12-10fuse: fix bad inodeMiklos Szeredi
Jan Kara's analysis of the syzbot report (edited): The reproducer opens a directory on FUSE filesystem, it then attaches dnotify mark to the open directory. After that a fuse_do_getattr() call finds that attributes returned by the server are inconsistent, and calls make_bad_inode() which, among other things does: inode->i_mode = S_IFREG; This then confuses dnotify which doesn't tear down its structures properly and eventually crashes. Avoid calling make_bad_inode() on a live inode: switch to a private flag on the fuse inode. Also add the test to ops which the bad_inode_ops would have caught. This bug goes back to the initial merge of fuse in 2.6.14... Reported-by: syzbot+f427adf9324b92652ccc@syzkaller.appspotmail.com Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Tested-by: Jan Kara <jack@suse.cz> Cc: <stable@vger.kernel.org>
2020-11-11fuse: add a flag FUSE_OPEN_KILL_SUIDGID for open() requestVivek Goyal
With FUSE_HANDLE_KILLPRIV_V2 support, server will need to kill suid/sgid/ security.capability on open(O_TRUNC), if server supports FUSE_ATOMIC_O_TRUNC. But server needs to kill suid/sgid only if caller does not have CAP_FSETID. Given server does not have this information, client needs to send this info to server. So add a flag FUSE_OPEN_KILL_SUIDGID to fuse_open_in request which tells server to kill suid/sgid (only if group execute is set). This flag is added to the FUSE_OPEN request, as well as the FUSE_CREATE request if the create was non-exclusive, since that might result in an existing file being opened/truncated. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-11-11fuse: don't send ATTR_MODE to kill suid/sgid for handle_killpriv_v2Vivek Goyal
If client does a write() on a suid/sgid file, VFS will first call fuse_setattr() with ATTR_KILL_S[UG]ID set. This requires sending setattr to file server with ATTR_MODE set to kill suid/sgid. But to do that client needs to know latest mode otherwise it is racy. To reduce the race window, current code first call fuse_do_getattr() to get latest ->i_mode and then resets suid/sgid bits and sends rest to server with setattr(ATTR_MODE). This does not reduce the race completely but narrows race window significantly. With fc->handle_killpriv_v2 enabled, it should be possible to remove this race completely. Do not kill suid/sgid with ATTR_MODE at all. It will be killed by server when WRITE request is sent to server soon. This is similar to fc->handle_killpriv logic. V2 is just more refined version of protocol. Hence this patch does not send ATTR_MODE to kill suid/sgid if fc->handle_killpriv_v2 is enabled. This creates an issue if fc->writeback_cache is enabled. In that case WRITE can be cached in guest and server might not see WRITE request and hence will not kill suid/sgid. Miklos suggested that in such cases, we should fallback to a writethrough WRITE instead and that will generate WRITE request and kill suid/sgid. This patch implements that too. But this relies on client seeing the suid/sgid set. If another client sets suid/sgid and this client does not see it immideately, then we will not fallback to writethrough WRITE. So this is one limitation with both fc->handle_killpriv_v2 and fc->writeback_cache enabled. Both the options are not fully compatible. But might be good enough for many use cases. Note: This patch is not checking whether security.capability is set or not when falling back to writethrough path. If suid/sgid is not set and only security.capability is set, that will be taken care of by file_remove_privs() call in ->writeback_cache path. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-11-11fuse: set FUSE_WRITE_KILL_SUIDGID in cached write pathVivek Goyal
With HANDLE_KILLPRIV_V2, server will need to kill suid/sgid if caller does not have CAP_FSETID. We already have a flag FUSE_WRITE_KILL_SUIDGID in WRITE request and we already set it in direct I/O path. To make it work in cached write path also, start setting FUSE_WRITE_KILL_SUIDGID in this path too. Set it only if fc->handle_killpriv_v2 is set. Otherwise client is responsible for kill suid/sgid. In case of direct I/O we set FUSE_WRITE_KILL_SUIDGID unconditionally because we don't call file_remove_privs() in that path (with cache=none option). Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-11-11fuse: rename FUSE_WRITE_KILL_PRIV to FUSE_WRITE_KILL_SUIDGIDMiklos Szeredi
Kernel has: ATTR_KILL_PRIV -> clear "security.capability" ATTR_KILL_SUID -> clear S_ISUID ATTR_KILL_SGID -> clear S_ISGID if executable Fuse has: FUSE_WRITE_KILL_PRIV -> clear S_ISUID and S_ISGID if executable So FUSE_WRITE_KILL_PRIV implies the complement of ATTR_KILL_PRIV, which is somewhat confusing. Also PRIV implies all privileges, including "security.capability". Change the name to FUSE_WRITE_KILL_SUIDGID and make FUSE_WRITE_KILL_PRIV an alias to perserve API compatibility Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-11-11fuse: launder page should wait for page writebackMiklos Szeredi
Qian Cai reports that the WARNING in tree_insert() can be triggered by a fuzzer with the following call chain: invalidate_inode_pages2_range() fuse_launder_page() fuse_writepage_locked() tree_insert() The reason is that another write for the same page is already queued. The simplest fix is to wait until the pending write is completed and only after that queue the new write. Since this case is very rare, the additional wait should not be a problem. Reported-by: Qian Cai <cai@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-10-19Merge tag 'fuse-update-5.10' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse Pull fuse updates from Miklos Szeredi: - Support directly accessing host page cache from virtiofs. This can improve I/O performance for various workloads, as well as reducing the memory requirement by eliminating double caching. Thanks to Vivek Goyal for doing most of the work on this. - Allow automatic submounting inside virtiofs. This allows unique st_dev/ st_ino values to be assigned inside the guest to files residing on different filesystems on the host. Thanks to Max Reitz for the patches. - Fix an old use after free bug found by Pradeep P V K. * tag 'fuse-update-5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse: (25 commits) virtiofs: calculate number of scatter-gather elements accurately fuse: connection remove fix fuse: implement crossmounts fuse: Allow fuse_fill_super_common() for submounts fuse: split fuse_mount off of fuse_conn fuse: drop fuse_conn parameter where possible fuse: store fuse_conn in fuse_req fuse: add submount support to <uapi/linux/fuse.h> fuse: fix page dereference after free virtiofs: add logic to free up a memory range virtiofs: maintain a list of busy elements virtiofs: serialize truncate/punch_hole and dax fault path virtiofs: define dax address space operations virtiofs: add DAX mmap support virtiofs: implement dax read/write operations virtiofs: introduce setupmapping/removemapping commands virtiofs: implement FUSE_INIT map_alignment field virtiofs: keep a list of free dax memory ranges virtiofs: add a mount option to enable dax virtiofs: set up virtio_fs dax_device ...
2020-09-18fuse: split fuse_mount off of fuse_connMax Reitz
We want to allow submounts for the same fuse_conn, but with different superblocks so that each of the submounts has its own device ID. To do so, we need to split all mount-specific information off of fuse_conn into a new fuse_mount structure, so that multiple mounts can share a single fuse_conn. We need to take care only to perform connection-level actions once (i.e. when the fuse_conn and thus the first fuse_mount are established, or when the last fuse_mount and thus the fuse_conn are destroyed). For example, fuse_sb_destroy() must invoke fuse_send_destroy() until the last superblock is released. To do so, we keep track of which fuse_mount is the root mount and perform all fuse_conn-level actions only when this fuse_mount is involved. Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-09-17fuse: fix the ->direct_IO() treatment of iov_iterAl Viro
the callers rely upon having any iov_iter_truncate() done inside ->direct_IO() countered by iov_iter_reexpand(). Reported-by: Qian Cai <cai@redhat.com> Tested-by: Qian Cai <cai@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-09-10virtiofs: serialize truncate/punch_hole and dax fault pathVivek Goyal
Currently in fuse we don't seem have any lock which can serialize fault path with truncate/punch_hole path. With dax support I need one for following reasons. 1. Dax requirement DAX fault code relies on inode size being stable for the duration of fault and want to serialize with truncate/punch_hole and they explicitly mention it. static vm_fault_t dax_iomap_pmd_fault(struct vm_fault *vmf, pfn_t *pfnp, const struct iomap_ops *ops) /* * Check whether offset isn't beyond end of file now. Caller is * supposed to hold locks serializing us with truncate / punch hole so * this is a reliable test. */ max_pgoff = DIV_ROUND_UP(i_size_read(inode), PAGE_SIZE); 2. Make sure there are no users of pages being truncated/punch_hole get_user_pages() might take references to page and then do some DMA to said pages. Filesystem might truncate those pages without knowing that a DMA is in progress or some I/O is in progress. So use dax_layout_busy_page() to make sure there are no such references and I/O is not in progress on said pages before moving ahead with truncation. 3. Limitation of kvm page fault error reporting If we are truncating file on host first and then removing mappings in guest lateter (truncate page cache etc), then this could lead to a problem with KVM. Say a mapping is in place in guest and truncation happens on host. Now if guest accesses that mapping, then host will take a fault and kvm will either exit to qemu or spin infinitely. IOW, before we do truncation on host, we need to make sure that guest inode does not have any mapping in that region or whole file. 4. virtiofs memory range reclaim Soon I will introduce the notion of being able to reclaim dax memory ranges from a fuse dax inode. There also I need to make sure that no I/O or fault is going on in the reclaimed range and nobody is using it so that range can be reclaimed without issues. Currently if we take inode lock, that serializes read/write. But it does not do anything for faults. So I add another semaphore fuse_inode->i_mmap_sem for this purpose. It can be used to serialize with faults. As of now, I am adding taking this semaphore only in dax fault path and not regular fault path because existing code does not have one. May be existing code can benefit from it as well to take care of some races, but that we can fix later if need be. For now, I am just focussing only on DAX path which is new path. Also added logic to take fuse_inode->i_mmap_sem in truncate/punch_hole/open(O_TRUNC) path to make sure file truncation and fuse dax fault are mutually exlusive and avoid all the above problems. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Cc: Dave Chinner <david@fromorbit.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-09-10virtiofs: add DAX mmap supportStefan Hajnoczi
Add DAX mmap() support. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-09-10virtiofs: implement dax read/write operationsVivek Goyal
This patch implements basic DAX support. mmap() is not implemented yet and will come in later patches. This patch looks into implemeting read/write. We make use of interval tree to keep track of per inode dax mappings. Do not use dax for file extending writes, instead just send WRITE message to daemon (like we do for direct I/O path). This will keep write and i_size change atomic w.r.t crash. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com> Signed-off-by: Peng Tao <tao.peng@linux.alibaba.com> Cc: Dave Chinner <david@fromorbit.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-08-04Merge tag 'uninit-macro-v5.9-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull uninitialized_var() macro removal from Kees Cook: "This is long overdue, and has hidden too many bugs over the years. The series has several "by hand" fixes, and then a trivial treewide replacement. - Clean up non-trivial uses of uninitialized_var() - Update documentation and checkpatch for uninitialized_var() removal - Treewide removal of uninitialized_var()" * tag 'uninit-macro-v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: compiler: Remove uninitialized_var() macro treewide: Remove uninitialized_var() usage checkpatch: Remove awareness of uninitialized_var() macro mm/debug_vm_pgtable: Remove uninitialized_var() usage f2fs: Eliminate usage of uninitialized_var() macro media: sur40: Remove uninitialized_var() usage KVM: PPC: Book3S PR: Remove uninitialized_var() usage clk: spear: Remove uninitialized_var() usage clk: st: Remove uninitialized_var() usage spi: davinci: Remove uninitialized_var() usage ide: Remove uninitialized_var() usage rtlwifi: rtl8192cu: Remove uninitialized_var() usage b43: Remove uninitialized_var() usage drbd: Remove uninitialized_var() usage x86/mm/numa: Remove uninitialized_var() usage docs: deprecated.rst: Add uninitialized_var()
2020-07-16treewide: Remove uninitialized_var() usageKees Cook
Using uninitialized_var() is dangerous as it papers over real bugs[1] (or can in the future), and suppresses unrelated compiler warnings (e.g. "unused variable"). If the compiler thinks it is uninitialized, either simply initialize the variable or make compiler changes. In preparation for removing[2] the[3] macro[4], remove all remaining needless uses with the following script: git grep '\buninitialized_var\b' | cut -d: -f1 | sort -u | \ xargs perl -pi -e \ 's/\buninitialized_var\(([^\)]+)\)/\1/g; s:\s*/\* (GCC be quiet|to make compiler happy) \*/$::g;' drivers/video/fbdev/riva/riva_hw.c was manually tweaked to avoid pathological white-space. No outstanding warnings were found building allmodconfig with GCC 9.3.0 for x86_64, i386, arm64, arm, powerpc, powerpc64le, s390x, mips, sparc64, alpha, and m68k. [1] https://lore.kernel.org/lkml/20200603174714.192027-1-glider@google.com/ [2] https://lore.kernel.org/lkml/CA+55aFw+Vbj0i=1TGqCR5vQkCzWJ0QxK6CernOU6eedsudAixw@mail.gmail.com/ [3] https://lore.kernel.org/lkml/CA+55aFwgbgqhbp1fkxvRKEpzyR5J8n1vKT1VZdz9knmPuXhOeg@mail.gmail.com/ [4] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@mail.gmail.com/ Reviewed-by: Leon Romanovsky <leonro@mellanox.com> # drivers/infiniband and mlx4/mlx5 Acked-by: Jason Gunthorpe <jgg@mellanox.com> # IB Acked-by: Kalle Valo <kvalo@codeaurora.org> # wireless drivers Reviewed-by: Chao Yu <yuchao0@huawei.com> # erofs Signed-off-by: Kees Cook <keescook@chromium.org>
2020-07-15fuse: Fix parameter for FS_IOC_{GET,SET}FLAGSChirantan Ekbote
The ioctl encoding for this parameter is a long but the documentation says it should be an int and the kernel drivers expect it to be an int. If the fuse driver treats this as a long it might end up scribbling over the stack of a userspace process that only allocated enough space for an int. This was previously discussed in [1] and a patch for fuse was proposed in [2]. From what I can tell the patch in [2] was nacked in favor of adding new, "fixed" ioctls and using those from userspace. However there is still no "fixed" version of these ioctls and the fact is that it's sometimes infeasible to change all userspace to use the new one. Handling the ioctls specially in the fuse driver seems like the most pragmatic way for fuse servers to support them without causing crashes in userspace applications that call them. [1]: https://lore.kernel.org/linux-fsdevel/20131126200559.GH20559@hall.aurel32.net/T/ [2]: https://sourceforge.net/p/fuse/mailman/message/31771759/ Signed-off-by: Chirantan Ekbote <chirantan@chromium.org> Fixes: 59efec7b9039 ("fuse: implement ioctl support") Cc: <stable@vger.kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-07-14fuse: don't ignore errors from fuse_writepages_fill()Vasily Averin
fuse_writepages() ignores some errors taken from fuse_writepages_fill() I believe it is a bug: if .writepages is called with WB_SYNC_ALL it should either guarantee that all data was successfully saved or return error. Fixes: 26d614df1da9 ("fuse: Implement writepages callback") Signed-off-by: Vasily Averin <vvs@virtuozzo.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-07-14fuse: clean up condition for writepage sendingMiklos Szeredi
fuse_writepages_fill uses following construction: if (wpa && ap->num_pages && (A || B || C)) { action; } else if (wpa && D) { if (E) { the same action; } } - ap->num_pages check is always true and can be removed - "if" and "else if" calls the same action and can be merged. Move checking A, B, C, D, E conditions to a helper, add comments. Original-patch-by: Vasily Averin <vvs@virtuozzo.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-07-14fuse: fix warning in tree_insert() and clean up writepage insertionMiklos Szeredi
fuse_writepages_fill() calls tree_insert() with ap->num_pages = 0 which triggers the following warning: WARNING: CPU: 1 PID: 17211 at fs/fuse/file.c:1728 tree_insert+0xab/0xc0 [fuse] RIP: 0010:tree_insert+0xab/0xc0 [fuse] Call Trace: fuse_writepages_fill+0x5da/0x6a0 [fuse] write_cache_pages+0x171/0x470 fuse_writepages+0x8a/0x100 [fuse] do_writepages+0x43/0xe0 Fix up the warning and clean up the code around rb-tree insertion: - Rename tree_insert() to fuse_insert_writeback() and make it return the conflicting entry in case of failure - Re-add tree_insert() as a wrapper around fuse_insert_writeback() - Rename fuse_writepage_in_flight() to fuse_writepage_add() and reverse the meaning of the return value to mean + "true" in case the writepage entry was successfully added + "false" in case it was in-fligt queued on an existing writepage entry's auxiliary list or the existing writepage entry's temporary page updated Switch from fuse_find_writeback() + tree_insert() to fuse_insert_writeback() - Move setting orig_pages to before inserting/updating the entry; this may result in the orig_pages value being discarded later in case of an in-flight request - In case of a new writepage entry use fuse_writepage_add() unconditionally, only set data->wpa if the entry was added. Fixes: 6b2fb79963fb ("fuse: optimize writepages search") Reported-by: kernel test robot <rong.a.chen@intel.com> Original-path-by: Vasily Averin <vvs@virtuozzo.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-07-14fuse: move rb_erase() before tree_insert()Miklos Szeredi
In fuse_writepage_end() the old writepages entry needs to be removed from the rbtree before inserting the new one, otherwise tree_insert() would fail. This is a very rare codepath and no reproducer exists. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-06-09Merge tag 'fuse-update-5.8' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse Pull fuse updates from Miklos Szeredi: - Fix a rare deadlock in virtiofs - Fix st_blocks in writeback cache mode - Fix wrong checks in splice move causing spurious warnings - Fix a race between a GETATTR request and a FUSE_NOTIFY_INVAL_INODE notification - Use rb-tree instead of linear search for pages currently under writeout by userspace - Fix copy_file_range() inconsistencies * tag 'fuse-update-5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse: fuse: copy_file_range should truncate cache fuse: fix copy_file_range cache issues fuse: optimize writepages search fuse: update attr_version counter on fuse_notify_inval_inode() fuse: don't check refcount after stealing page fuse: fix weird page warning fuse: use dump_page virtiofs: do not use fuse_fill_super_common() for device installation fuse: always allow query of st_dev fuse: always flush dirty data on close(2) fuse: invalidate inode attr in writeback cache mode fuse: Update stale comment in queue_interrupt() fuse: BUG_ON correction in fuse_dev_splice_write() virtiofs: Add mount option and atime behavior to the doc virtiofs: schedule blocking async replies in separate worker
2020-06-02fuse: convert from readpages to readaheadMatthew Wilcox (Oracle)
Implement the new readahead operation in fuse by using __readahead_batch() to fill the array of pages in fuse_args_pages directly. This lets us inline fuse_readpages_fill() into fuse_readahead(). [willy@infradead.org: build fix] Link: http://lkml.kernel.org/r/20200415025938.GB5820@bombadil.infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: William Kucharski <william.kucharski@oracle.com> Acked-by: Miklos Szeredi <mszeredi@redhat.com> Cc: Chao Yu <yuchao0@huawei.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Cong Wang <xiyou.wangcong@gmail.com> Cc: Darrick J. Wong <darrick.wong@oracle.com> Cc: Eric Biggers <ebiggers@google.com> Cc: Gao Xiang <gaoxiang25@huawei.com> Cc: Jaegeuk Kim <jaegeuk@kernel.org> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Joseph Qi <joseph.qi@linux.alibaba.com> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Zi Yan <ziy@nvidia.com> Cc: Johannes Thumshirn <johannes.thumshirn@wdc.com> Link: http://lkml.kernel.org/r/20200414150233.24495-25-willy@infradead.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-05-20fuse: copy_file_range should truncate cacheMiklos Szeredi
After the copy operation completes the cache is not up-to-date. Truncate all pages in the interval that has successfully been copied. Truncating completely copied dirty pages is okay, since the data has been overwritten anyway. Truncating partially copied dirty pages is not okay; add a comment for now. Fixes: 88bc7d5097a1 ("fuse: add support for copy_file_range()") Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-05-20fuse: fix copy_file_range cache issuesMiklos Szeredi
a) Dirty cache needs to be written back not just in the writeback_cache case, since the dirty pages may come from memory maps. b) The fuse_writeback_range() helper takes an inclusive interval, so the end position needs to be pos+len-1 instead of pos+len. Fixes: 88bc7d5097a1 ("fuse: add support for copy_file_range()") Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-05-19fuse: optimize writepages searchMaxim Patlasov
Re-work fi->writepages, replacing list with rb-tree. This improves performance because kernel fuse iterates through fi->writepages for each writeback page and typical number of entries is about 800 (for 100MB of fuse writeback). Before patch: 10240+0 records in 10240+0 records out 10737418240 bytes (11 GB) copied, 41.3473 s, 260 MB/s 2 1 0 57445400 40416 6323676 0 0 33 374743 8633 19210 1 8 88 3 0 29.86% [kernel] [k] _raw_spin_lock 26.62% [fuse] [k] fuse_page_is_writeback After patch: 10240+0 records in 10240+0 records out 10737418240 bytes (11 GB) copied, 21.4954 s, 500 MB/s 2 9 0 53676040 31744 10265984 0 0 64 854790 10956 48387 1 6 88 6 0 23.55% [kernel] [k] copy_user_enhanced_fast_string 9.87% [kernel] [k] __memcpy 3.10% [kernel] [k] _raw_spin_lock Signed-off-by: Maxim Patlasov <mpatlasov@virtuozzo.com> Signed-off-by: Vasily Averin <vvs@virtuozzo.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-05-19fuse: always flush dirty data on close(2)Miklos Szeredi
We want cached data to synced with the userspace filesystem on close(), for example to allow getting correct st_blocks value. Do this regardless of whether the userspace filesystem implements a FLUSH method or not. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-05-19fuse: invalidate inode attr in writeback cache modeEryu Guan
Under writeback mode, inode->i_blocks is not updated, making utils du read st.blocks as 0. For example, when using virtiofs (cache=always & nondax mode) with writeback_cache enabled, writing a new file and check its disk usage with du, du reports 0 usage. # uname -r 5.6.0-rc6+ # mount -t virtiofs virtiofs /mnt/virtiofs # rm -f /mnt/virtiofs/testfile # create new file and do extend write # xfs_io -fc "pwrite 0 4k" /mnt/virtiofs/testfile wrote 4096/4096 bytes at offset 0 4 KiB, 1 ops; 0.0001 sec (28.103 MiB/sec and 7194.2446 ops/sec) # du -k /mnt/virtiofs/testfile 0 <==== disk usage is 0 # stat -c %s,%b /mnt/virtiofs/testfile 4096,0 <==== i_size is correct, but st_blocks is 0 Fix it by invalidating attr in fuse_flush(), so we get up-to-date attr from server on next getattr. Signed-off-by: Eryu Guan <eguan@linux.alibaba.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-04-20virtiofs: schedule blocking async replies in separate workerVivek Goyal
In virtiofs (unlike in regular fuse) processing of async replies is serialized. This can result in a deadlock in rare corner cases when there's a circular dependency between the completion of two or more async replies. Such a deadlock can be reproduced with xfstests:generic/503 if TEST_DIR == SCRATCH_MNT (which is a misconfiguration): - Process A is waiting for page lock in worker thread context and blocked (virtio_fs_requests_done_work()). - Process B is holding page lock and waiting for pending writes to finish (fuse_wait_on_page_writeback()). - Write requests are waiting in virtqueue and can't complete because worker thread is blocked on page lock (process A). Fix this by creating a unique work_struct for each async reply that can block (O_DIRECT read). Fixes: a62a8ef9d97d ("virtio-fs: add virtiofs filesystem") Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-02-06fuse: use true,false for bool variablezhengbin
Fixes coccicheck warning: fs/fuse/readdir.c:335:1-19: WARNING: Assignment of 0/1 to bool variable fs/fuse/file.c:1398:2-19: WARNING: Assignment of 0/1 to bool variable fs/fuse/file.c:1400:2-20: WARNING: Assignment of 0/1 to bool variable fs/fuse/cuse.c:454:1-20: WARNING: Assignment of 0/1 to bool variable fs/fuse/cuse.c:455:1-19: WARNING: Assignment of 0/1 to bool variable fs/fuse/inode.c:497:2-17: WARNING: Assignment of 0/1 to bool variable fs/fuse/inode.c:504:2-23: WARNING: Assignment of 0/1 to bool variable fs/fuse/inode.c:511:2-22: WARNING: Assignment of 0/1 to bool variable fs/fuse/inode.c:518:2-23: WARNING: Assignment of 0/1 to bool variable fs/fuse/inode.c:522:2-26: WARNING: Assignment of 0/1 to bool variable fs/fuse/inode.c:526:2-18: WARNING: Assignment of 0/1 to bool variable fs/fuse/inode.c:1000:1-20: WARNING: Assignment of 0/1 to bool variable Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: zhengbin <zhengbin13@huawei.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-02-06fuse: don't overflow LLONG_MAX with end offsetMiklos Szeredi
Handle the special case of fuse_readpages() wanting to read the last page of a hugest file possible and overflowing the end offset in the process. This is basically to unbreak xfstests:generic/525 and prevent filesystems from doing bad things with an overflowing offset. Reported-by: Xiao Yang <ice_yangxiao@163.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-02-06fix up iter on short count in fuse_direct_io()Miklos Szeredi
fuse_direct_io() can end up advancing the iterator by more than the amount of data read or written. This case is handled by the generic code if going through ->direct_IO(), but not in the FOPEN_DIRECT_IO case. Fix by reverting the extra bytes from the iterator in case of error or a short count. To test: install lxcfs, then the following testcase int fd = open("/var/lib/lxcfs/proc/uptime", O_RDONLY); sendfile(1, fd, NULL, 16777216); sendfile(1, fd, NULL, 16777216); will spew WARN_ON() in iov_iter_pipe(). Reported-by: Peter Geis <pgwipeout@gmail.com> Reported-by: Al Viro <viro@zeniv.linux.org.uk> Fixes: 3c3db095b68c ("fuse: use iov_iter based generic splice helpers") Cc: <stable@vger.kernel.org> # v5.1 Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-01-16fuse: fix fuse_send_readpages() in the syncronous read caseMiklos Szeredi
Buffered read in fuse normally goes via: -> generic_file_buffered_read() -> fuse_readpages() -> fuse_send_readpages() ->fuse_simple_request() [called since v5.4] In the case of a read request, fuse_simple_request() will return a non-negative bytecount on success or a negative error value. A positive bytecount was taken to be an error and the PG_error flag set on the page. This resulted in generic_file_buffered_read() falling back to ->readpage(), which would repeat the read request and succeed. Because of the repeated read succeeding the bug was not detected with regression tests or other use cases. The FTP module in GVFS however fails the second read due to the non-seekable nature of FTP downloads. Fix by checking and ignoring positive return value from fuse_simple_request(). Reported-by: Ondrej Holy <oholy@redhat.com> Link: https://gitlab.gnome.org/GNOME/gvfs/issues/441 Fixes: 134831e36bbd ("fuse: convert readpages to simple api") Cc: <stable@vger.kernel.org> # v5.4 Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-11-27fuse: fix leak of fuse_io_privMiklos Szeredi
exit_aio() is sometimes stuck in wait_for_completion() after aio is issued with direct IO and the task receives a signal. The reason is failure to call ->ki_complete() due to a leaked reference to fuse_io_priv. This happens in fuse_async_req_send() if fuse_simple_background() returns an error (e.g. -EINTR). In this case the error value is propagated via io->err, so return success to not confuse callers. This issue is tracked as a virtio-fs issue: https://gitlab.com/virtio-fs/qemu/issues/14 Reported-by: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com> Fixes: 45ac96ed7c36 ("fuse: convert direct_io to simple api") Cc: <stable@vger.kernel.org> # v5.4 Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-11-12fuse: verify write returnMiklos Szeredi
Make sure filesystem is not returning a bogus number of bytes written. Fixes: ea9b9907b82a ("fuse: implement perform_write") Cc: <stable@vger.kernel.org> # v2.6.26 Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-10-23fuse: redundant get_fuse_inode() calls in fuse_writepages_fill()Vasily Averin
Currently fuse_writepages_fill() calls get_fuse_inode() few times with the same argument. Signed-off-by: Vasily Averin <vvs@virtuozzo.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-10-23fuse: truncate pending writes on O_TRUNCMiklos Szeredi
Make sure cached writes are not reordered around open(..., O_TRUNC), with the obvious wrong results. Fixes: 4d99ff8f12eb ("fuse: Turn writeback cache on") Cc: <stable@vger.kernel.org> # v3.15+ Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-09-24fuse: kmemcg account fs dataKhazhismel Kumykov
account per-file, dentry, and inode data blockdev/superblock and temporary per-request data was left alone, as this usually isn't accounted Reviewed-by: Shakeel Butt <shakeelb@google.com> Signed-off-by: Khazhismel Kumykov <khazhy@google.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-09-24fuse: fix missing unlock_page in fuse_writepage()Vasily Averin
unlock_page() was missing in case of an already in-flight write against the same page. Signed-off-by: Vasily Averin <vvs@virtuozzo.com> Fixes: ff17be086477 ("fuse: writepage: skip already in flight") Cc: <stable@vger.kernel.org> # v3.13 Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-09-10fuse: simplify request allocationMiklos Szeredi
Page arrays are not allocated together with the request anymore. Get rid of the dead code Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-09-10fuse: convert release to simple apiMiklos Szeredi
Since we cannot reserve the request structure up-front, make sure that the request allocation doesn't fail using __GFP_NOFAIL. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-09-10fuse: convert writepages to simple apiMiklos Szeredi
Derive fuse_writepage_args from fuse_io_args. Sending the request is tricky since it was done with fi->lock held, hence we must either use atomic allocation or release the lock. Both are possible so try atomic first and if it fails, release the lock and do the regular allocation with GFP_NOFS and __GFP_NOFAIL. Both flags are necessary for correct operation. Move the page realloc function from dev.c to file.c and convert to using fuse_writepage_args. The last caller of fuse_write_fill() is gone, so get rid of it. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-09-10fuse: convert readdir to simple apiMiklos Szeredi
The old fuse_read_fill() helper can be deleted, now that the last user is gone. The fuse_io_args struct is moved to fuse_i.h so it can be shared between readdir/read code. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-09-10fuse: convert readpages to simple apiMiklos Szeredi
Need to extend fuse_io_args with 'attr_ver' and 'ff' members, that take the functionality of the same named members in fuse_req. fuse_short_read() can now take struct fuse_args_pages. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-09-10fuse: convert direct_io to simple apiMiklos Szeredi
Change of semantics in fuse_async_req_send/fuse_send_(read|write): these can now return error, in which case the 'end' callback isn't called, so the fuse_io_args object needs to be freed. Added verification that the return value is sane (less than or equal to the requested read/write size). Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-09-10fuse: convert sync write to simple apiMiklos Szeredi
Extract a fuse_write_flags() helper that converts ki_flags relevant write to open flags. The other parts of fuse_send_write() aren't used in the fuse_perform_write() case. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-09-10fuse: covert readpage to simple apiMiklos Szeredi
Derive fuse_io_args from struct fuse_args_pages. This will be used for both synchronous and asynchronous read/write requests. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-09-10fuse: fuse_short_read(): don't take fuse_req as argumentMiklos Szeredi
This will allow the use of this function when converting to the simple api (which doesn't use fuse_req). Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-09-10fuse: convert ioctl to simple apiMiklos Szeredi
fuse_simple_request() is converted to return length of last (instead of single) out arg, since FUSE_IOCTL_OUT has two out args, the second of which is variable length. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-09-10fuse: move page allocMiklos Szeredi
fuse_req_pages_alloc() is moved to file.c, since its internal use by the device code will eventually be removed. Rename to fuse_pages_alloc() to signify that it's not only usable for fuse_req page array. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-09-10fuse: convert destroy to simple apiMiklos Szeredi
We can use the "force" flag to make sure the DESTROY request is always sent to userspace. So no need to keep it allocated during the lifetime of the filesystem. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-09-10fuse: convert flush to simple apiMiklos Szeredi
Add 'force' to fuse_args and use fuse_get_req_nofail_nopages() to allocate the request in that case. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>