kernel/linux.git/fs/nfs/direct.c, branch linux-7.1.y

nfs: direct: drop useless initializer in nfs_direct_write_completion()

2025-04-28T03:25:44+00:00

In nfs_direct_write_completion(), the local variable req isn't used outside the *while* loop and is assigned to right at the start of that loop's body, so its initializer appears useless -- drop it; then move the declaration to the loop body (which happens to have a pointless empty line anyway)... Found by Linux Verification Center (linuxtesting.org) with the Svace static analysis tool. Signed-off-by: Sergey Shtylyov Reviewed-by: Benjamin Coddington Link: https://lore.kernel.org/r/416219f5-7983-484b-b5a7-5fb7da9561f7@omp.ru Signed-off-by: Trond Myklebust

NFS: Adjust delegated timestamps for O_DIRECT reads and writes

2025-02-19T21:45:24+00:00

Adjust the timestamps if O_DIRECT is being combined with attribute delegations. Fixes: e12912d94137 ("NFSv4: Add support for delegated atime and mtime attributes") Signed-off-by: Trond Myklebust Signed-off-by: Anna Schumaker

NFS: O_DIRECT writes must check and adjust the file length

2025-02-19T21:45:23+00:00

While it is uncommon for delegations to be held while O_DIRECT writes are in progress, it is possible. The xfstests generic/647 and generic/729 both end up triggering that state, and end up failing due to the fact that the file size is not adjusted. Reported-by: Chuck Lever Link: https://bugzilla.kernel.org/show_bug.cgi?id=219738 Cc: stable@vger.kernel.org Signed-off-by: Trond Myklebust Signed-off-by: Anna Schumaker

nfs/localio: add direct IO enablement with sync and async IO support

2025-01-14T22:04:02+00:00

This commit simply adds the required O_DIRECT plumbing. It doesn't address the fact that NFS doesn't ensure all writes are page aligned (nor device logical block size aligned as required by O_DIRECT). Because NFS will read-modify-write for IO that isn't aligned, LOCALIO will not use O_DIRECT semantics by default if/when an application requests the use of O_DIRECT. Allow the use of O_DIRECT semantics by: 1: Adding a flag to the nfs_pgio_header struct to allow the NFS O_DIRECT layer to signal that O_DIRECT was used by the application 2: Adding a 'localio_O_DIRECT_semantics' NFS module parameter that when enabled will cause LOCALIO to use O_DIRECT semantics (this may cause IO to fail if applications do not properly align their IO). This commit is derived from code developed by Weston Andros Adamson. Signed-off-by: Mike Snitzer Reviewed-by: Jeff Layton Signed-off-by: Anna Schumaker

fs/nfs/io: make nfs_start_io_*() killable

2024-11-28T17:55:33+00:00

This allows killing processes that wait for a lock when one process is stuck waiting for the NFS server. This aims to complete the coverage of NFS operations being killable, like nfs_direct_wait() does, for example. Signed-off-by: Max Kellermann Signed-off-by: Trond Myklebust

nfs: drop the incorrect assertion in nfs_swap_rw()

2024-06-25T03:52:11+00:00

Since commit 2282679fb20b ("mm: submit multipage write for SWP_FS_OPS swap-space"), we can plug multiple pages then unplug them all together. That means iov_iter_count(iter) could be way bigger than PAGE_SIZE, it actually equals the size of iov_iter_npages(iter, INT_MAX). Note this issue has nothing to do with large folios as we don't support THP_SWPOUT to non-block devices. [v-songbaohua@oppo.com: figure out the cause and correct the commit message] Link: https://lkml.kernel.org/r/20240618065647.21791-1-21cnbao@gmail.com Fixes: 2282679fb20b ("mm: submit multipage write for SWP_FS_OPS swap-space") Signed-off-by: Christoph Hellwig Signed-off-by: Barry Song Closes: https://lore.kernel.org/linux-mm/20240617053201.GA16852@lst.de/ Reviewed-by: Martin Wege Cc: NeilBrown Cc: Anna Schumaker Cc: Steve French Cc: Trond Myklebust Cc: Chuanhua Han Cc: Ryan Roberts Cc: Chris Li Cc: "Huang, Ying" Cc: Jeff Layton Cc: Matthew Wilcox Cc: Signed-off-by: Andrew Morton

Merge tag 'nfs-for-6.9-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

2024-03-16T18:44:00+00:00

Pull NFS client updates from Trond Myklebust: "Highlights include: Bugfixes: - Fix for an Oops in the NFSv4.2 listxattr handler - Correct an incorrect buffer size in listxattr - Fix for an Oops in the pNFS flexfiles layout - Fix a refcount leak in NFS O_DIRECT writes - Fix missing locking in NFS O_DIRECT - Avoid an infinite loop in pnfs_update_layout - Fix an overflow in the RPC waitqueue queue length counter - Ensure that pNFS I/O is also protected by TLS when xprtsec is specified by the mount options - Fix a leaked folio lock in the netfs read code - Fix a potential deadlock in fscache - Allow setting the fscache uniquifier in NFSv4 - Fix an off by one in root_nfs_cat() - Fix another off by one in rpc_sockaddr2uaddr() - nfs4_do_open() can incorrectly trigger state recovery - Various fixes for connection shutdown Features and cleanups: - Ensure that containers only see their own RPC and NFS stats - Enable nconnect for RDMA - Remove dead code from nfs_writepage_locked() - Various tracepoint additions to track EXCHANGE_ID, GETDEVICEINFO, and mount options" * tag 'nfs-for-6.9-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (29 commits) nfs: fix panic when nfs4_ff_layout_prepare_ds() fails NFS: trace the uniquifier of fscache NFS: Read unlock folio on nfs_page_create_from_folio() error NFS: remove unused variable nfs_rpcstat nfs: fix UAF in direct writes nfs: properly protect nfs_direct_req fields NFS: enable nconnect for RDMA NFSv4: nfs4_do_open() is incorrectly triggering state recovery NFS: avoid infinite loop in pnfs_update_layout. NFS: remove sync_mode test from nfs_writepage_locked() NFSv4.1/pnfs: fix NFS with TLS in pnfs NFS: Fix an off by one in root_nfs_cat() nfs: make the rpc_stat per net namespace nfs: expose /proc/net/sunrpc/nfs in net namespaces sunrpc: add a struct rpc_stats arg to rpc_create_args nfs: remove unused NFS_CALL macro NFSv4.1: add tracepoint to trunked nfs4_exchange_id calls NFS: Fix nfs_netfs_issue_read() xarray locking for writeback interrupt SUNRPC: increase size of rpc_wait_queue.qlen from unsigned short to unsigned int nfs: fix regression in handling of fsc= option in NFSv4 ...

mm, slab: remove last vestiges of SLAB_MEM_SPREAD

2024-03-13T03:32:19+00:00

Yes, yes, I know the slab people were planning on going slow and letting every subsystem fight this thing on their own. But let's just rip off the band-aid and get it over and done with. I don't want to see a number of unnecessary pull requests just to get rid of a flag that no longer has any meaning. This was mainly done with a couple of 'sed' scripts and then some manual cleanup of the end result. Link: https://lore.kernel.org/all/CAHk-=wji0u+OOtmAOD-5JV3SXcRJF___k_+8XNKmak0yd5vW1Q@mail.gmail.com/ Signed-off-by: Linus Torvalds

nfs: fix UAF in direct writes

2024-03-09T14:14:51+00:00

In production we have been hitting the following warning consistently ------------[ cut here ]------------ refcount_t: underflow; use-after-free. WARNING: CPU: 17 PID: 1800359 at lib/refcount.c:28 refcount_warn_saturate+0x9c/0xe0 Workqueue: nfsiod nfs_direct_write_schedule_work [nfs] RIP: 0010:refcount_warn_saturate+0x9c/0xe0 PKRU: 55555554 Call Trace: ? __warn+0x9f/0x130 ? refcount_warn_saturate+0x9c/0xe0 ? report_bug+0xcc/0x150 ? handle_bug+0x3d/0x70 ? exc_invalid_op+0x16/0x40 ? asm_exc_invalid_op+0x16/0x20 ? refcount_warn_saturate+0x9c/0xe0 nfs_direct_write_schedule_work+0x237/0x250 [nfs] process_one_work+0x12f/0x4a0 worker_thread+0x14e/0x3b0 ? ZSTD_getCParams_internal+0x220/0x220 kthread+0xdc/0x120 ? __btf_name_valid+0xa0/0xa0 ret_from_fork+0x1f/0x30 This is because we're completing the nfs_direct_request twice in a row. The source of this is when we have our commit requests to submit, we process them and send them off, and then in the completion path for the commit requests we have if (nfs_commit_end(cinfo.mds)) nfs_direct_write_complete(dreq); However since we're submitting asynchronous requests we sometimes have one that completes before we submit the next one, so we end up calling complete on the nfs_direct_request twice. The only other place we use nfs_generic_commit_list() is in __nfs_commit_inode, which wraps this call in a nfs_commit_begin(); nfs_commit_end(); Which is a common pattern for this style of completion handling, one that is also repeated in the direct code with get_dreq()/put_dreq() calls around where we process events as well as in the completion paths. Fix this by using the same pattern for the commit requests. Before with my 200 node rocksdb stress running this warning would pop every 10ish minutes. With my patch the stress test has been running for several hours without popping. Signed-off-by: Josef Bacik Cc: stable@vger.kernel.org Signed-off-by: Trond Myklebust

nfs: properly protect nfs_direct_req fields

2024-03-09T14:14:51+00:00

We protect accesses to the nfs_direct_req fields with the dreq->lock ever where except nfs_direct_commit_complete. This isn't a huge deal, but it does lead to confusion, and we could potentially end up setting NFS_ODIRECT_RESCHED_WRITES in one thread where we've had an error in another. Clean this up to properly protect ->error and ->flags in the commit completion path. Signed-off-by: Josef Bacik Signed-off-by: Trond Myklebust