kernel/linux.git/fs/afs/file.c, branch v7.1

netfs: Fix potential for tearing in ->remote_i_size and ->zero_point

2026-05-12T12:42:30+00:00

Fix potential tearing in using ->remote_i_size and ->zero_point by copying i_size_read() and i_size_write() and using the same seqcount as for i_size. We need to make sure that netfslib and the filesystems that use it always hold i_lock whilst updating any of the sizes to prevent i_size_seqcount from getting corrupted. Fixes: 4058f742105e ("netfs: Keep track of the actual remote file size") Fixes: 100ccd18bb41 ("netfs: Optimise away reads above the point at which there can be no data") Closes: https://sashiko.dev/#/patchset/20260414082004.3756080-1-dhowells%40redhat.com Signed-off-by: David Howells Link: https://patch.msgid.link/20260512123404.719402-6-dhowells@redhat.com cc: Paulo Alcantara cc: Matthew Wilcox cc: netfs@lists.linux.dev cc: linux-fsdevel@vger.kernel.org Signed-off-by: Christian Brauner

fs: afs: restore mmap_prepare implementation

2026-04-05T20:53:43+00:00

Commit 9d5403b1036c ("fs: convert most other generic_file_*mmap() users to .mmap_prepare()") updated AFS to use the mmap_prepare callback in favour of the deprecated mmap callback. However, it did not account for the fact that mmap_prepare is called pre-merge, and may then be merged, nor that mmap_prepare can fail to map due to an out of memory error. This change was therefore since reverted. Both of those are cases in which we should not be incrementing a reference count. With the newly added vm_ops->mapped callback available, we can simply defer this operation to that callback which is only invoked once the mapping is successfully in place (but not yet visible to userspace as the mmap and VMA write locks are held). This allows us to once again reimplement the .mmap_prepare implementation for this file system. Therefore add afs_mapped() to implement this callback for AFS, and remove the code doing so in afs_mmap_prepare(). Also update afs_vm_open(), afs_vm_close() and afs_vm_map_pages() to be consistent in how the vnode is accessed. Link: https://lkml.kernel.org/r/ad9a94350a9c7d2bdab79fc397ef0f64d3412d71.1774045440.git.ljs@kernel.org Signed-off-by: Lorenzo Stoakes (Oracle) Acked-by: Vlastimil Babka (SUSE) Cc: Alexander Shishkin Cc: Alexandre Torgue Cc: Al Viro Cc: Arnd Bergmann Cc: Bodo Stroesser Cc: Christian Brauner Cc: Clemens Ladisch Cc: David Hildenbrand Cc: David Howells Cc: Dexuan Cui Cc: Greg Kroah-Hartman Cc: Haiyang Zhang Cc: Jan Kara Cc: Jann Horn Cc: Jonathan Corbet Cc: K. Y. Srinivasan Cc: Liam Howlett Cc: Long Li Cc: Marc Dionne Cc: "Martin K. Petersen" Cc: Maxime Coquelin Cc: Michal Hocko Cc: Mike Rapoport Cc: Miquel Raynal Cc: Pedro Falcato Cc: Richard Weinberger Cc: Ryan Roberts Cc: Suren Baghdasaryan Cc: Vignesh Raghavendra Cc: Wei Liu Signed-off-by: Andrew Morton

fs: afs: revert mmap_prepare() change

2026-04-05T20:53:43+00:00

Partially reverts commit 9d5403b1036c ("fs: convert most other generic_file_*mmap() users to .mmap_prepare()"). This is because the .mmap invocation establishes a refcount, but .mmap_prepare is called at a point where a merge or an allocation failure might happen after the call, which would leak the refcount increment. Functionality is being added to permit the use of .mmap_prepare in this case, but in the interim, we need to fix this. Link: https://lkml.kernel.org/r/08804c94e39d9102a3a8fbd12385e8aa079ba1d3.1774045440.git.ljs@kernel.org Fixes: 9d5403b1036c ("fs: convert most other generic_file_*mmap() users to .mmap_prepare()") Signed-off-by: Lorenzo Stoakes (Oracle) Acked-by: Vlastimil Babka (SUSE) Cc: Alexander Shishkin Cc: Alexandre Torgue Cc: Al Viro Cc: Arnd Bergmann Cc: Bodo Stroesser Cc: Christian Brauner Cc: Clemens Ladisch Cc: David Hildenbrand Cc: David Howells Cc: Dexuan Cui Cc: Greg Kroah-Hartman Cc: Haiyang Zhang Cc: Jan Kara Cc: Jann Horn Cc: Jonathan Corbet Cc: K. Y. Srinivasan Cc: Liam Howlett Cc: Long Li Cc: Marc Dionne Cc: "Martin K. Petersen" Cc: Maxime Coquelin Cc: Michal Hocko Cc: Mike Rapoport Cc: Miquel Raynal Cc: Pedro Falcato Cc: Richard Weinberger Cc: Ryan Roberts Cc: Suren Baghdasaryan Cc: Vignesh Raghavendra Cc: Vlastimil Babka (SUSE) Cc: Wei Liu Cc: Signed-off-by: Andrew Morton

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-22T01:09:51+00:00

This was done entirely with mindless brute force, using git grep -l '\

treewide: Replace kmalloc with kmalloc_obj for non-scalar types

2026-02-21T09:02:28+00:00

This is the result of running the Coccinelle script from scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to avoid scalar types (which need careful case-by-case checking), and instead replace kmalloc-family calls that allocate struct or union object instances: Single allocations: kmalloc(sizeof(TYPE), ...) are replaced with: kmalloc_obj(TYPE, ...) Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...) are replaced with: kmalloc_objs(TYPE, COUNT, ...) Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...) are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...) (where TYPE may also be *VAR) The resulting allocations no longer return "void *", instead returning "TYPE *". Signed-off-by: Kees Cook

fs: convert most other generic_file_*mmap() users to .mmap_prepare()

2025-06-19T11:56:57+00:00

Update nearly all generic_file_mmap() and generic_file_readonly_mmap() callers to use generic_file_mmap_prepare() and generic_file_readonly_mmap_prepare() respectively. We update blkdev, 9p, afs, erofs, ext2, nfs, ntfs3, smb, ubifs and vboxsf file systems this way. Remaining users we cannot yet update are ecryptfs, fuse and cramfs. The former two are nested file systems that must support any underlying file ssytem, and cramfs inserts a mixed mapping which currently requires a VMA. Once all file systems have been converted to mmap_prepare(), we can then update nested file systems. Signed-off-by: Lorenzo Stoakes Link: https://lore.kernel.org/08db85970d89b17a995d2cffae96fb4cc462377f.1750099179.git.lorenzo.stoakes@oracle.com Signed-off-by: Christian Brauner

afs: Add a tracepoint for afs_read_receive()

2024-12-20T21:34:09+00:00

Add a tracepoint for afs_read_receive() to allow potential missed wakeups to be debugged. Signed-off-by: David Howells Link: https://lore.kernel.org/r/20241216204124.3752367-32-dhowells@redhat.com cc: Marc Dionne cc: linux-afs@lists.infradead.org Signed-off-by: Christian Brauner

afs: Make {Y,}FS.FetchData an asynchronous operation

2024-12-20T21:34:08+00:00

Make FS.FetchData and YFS.FetchData an asynchronous operation in that the request is queued in AF_RXRPC and then we return to the caller rather than waiting. Processing of the returning packets is then done inline if it's a synchronous VFS/VM call (readdir, read_folio, sync DIO, prep for write) or offloaded to a workqueue if asynchronous VM calls (eg. readahead, async DIO). This reduces the chain of workqueues invoking workqueues and cuts out some of the overhead, driving rxrpc data extraction and netfslib read collection from a thread that's going to block to completion anyway if possible. The ->done() call op is also split with ->immediate_cancel() handling the cancellation on failure to begin the call and ->done() handling the rest. This means that the AFS async FetchData code doesn't try to terminate the netfs subrequest twice. Signed-off-by: David Howells Link: https://lore.kernel.org/r/20241216204124.3752367-26-dhowells@redhat.com cc: Marc Dionne cc: linux-afs@lists.infradead.org Signed-off-by: Christian Brauner

afs: Eliminate afs_read

2024-12-20T21:34:07+00:00

Now that directory and symlink reads go through netfslib, the afs_read struct is mostly redundant with almost all data duplicated in the netfs_io_request and netfs_io_subrequest structs that are also available any time we're doing a fetch. Eliminate afs_read by moving the one field we still need there to the afs_call struct (we may be given a different amount of data than what we asked for and have to track what remains of that) and using the netfs_io_subrequest directly instead. Signed-off-by: David Howells Link: https://lore.kernel.org/r/20241216204124.3752367-24-dhowells@redhat.com cc: Marc Dionne cc: linux-afs@lists.infradead.org Signed-off-by: Christian Brauner

afs: Use netfslib for symlinks, allowing them to be cached

2024-12-20T21:34:07+00:00

Use netfslib to read symlinks, thereby allowing them to be cached by fscache and cachefiles. Signed-off-by: David Howells Link: https://lore.kernel.org/r/20241216204124.3752367-23-dhowells@redhat.com cc: Marc Dionne cc: Jeff Layton cc: linux-afs@lists.infradead.org cc: netfs@lists.linux.dev cc: linux-fsdevel@vger.kernel.org Signed-off-by: Christian Brauner