kernel/linux.git/fs/afs/file.c, branch linux-7.0.y

fs: afs: revert mmap_prepare() change

2026-05-07T04:13:43+00:00

commit fbfc6578eaca12daa0c09df1e9ba7f2c657b49da upstream. 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 Signed-off-by: Greg Kroah-Hartman

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

afs: Use netfslib for directories

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

In the AFS ecosystem, directories are just a special type of file that is downloaded and parsed locally. Download is done by the same mechanism as ordinary files and the data can be cached. There is one important semantic restriction on directories over files: the client must download the entire directory in one go because, for example, the server could fabricate the contents of the blob on the fly with each download and give a different image each time. So that we can cache the directory download, switch AFS directory support over to using the netfslib single-object API, thereby allowing directory content to be stored in the local cache. To make this work, the following changes are made: (1) A directory's contents are now stored in a folio_queue chain attached to the afs_vnode (inode) struct rather than its associated pagecache, though multipage folios are still used to hold the data. The folio queue is discarded when the directory inode is evicted. This also helps with the phasing out of ITER_XARRAY. (2) Various directory operations are made to use and unuse the cache cookie. (3) The content checking, content dumping and content iteration are now performed with a standard iov_iter iterator over the contents of the folio queue. (4) Iteration and modification must be done with the vnode's validate_lock held. In conjunction with (1), this means that the iteration can be done without the need to lock pages or take extra refs on them, unlike when accessing ->i_pages. (5) Convert to using netfs_read_single() to read data. (6) Provide a ->writepages() to call netfs_writeback_single() to save the data to the cache according to the VM's scheduling whilst holding the validate_lock read-locked as (4). (7) Change local directory image editing functions: (a) Provide a function to get a specific block by number from the folio_queue as we can no longer use the i_pages xarray to locate folios by index. This uses a cursor to remember the current position as we need to iterate through the directory contents. The block is kmapped before being returned. (b) Make the function in (a) extend the directory by an extra folio if we run out of space. (c) Raise the check of the block free space counter, for those blocks that have one, higher in the function to eliminate a call to get a block. (d) Remove the page unlocking and putting done during the editing loops. This is no longer necessary as the folio_queue holds the references and the pages are no longer in the pagecache. (e) Mark the inode dirty and pin the cache usage till writeback at the end of a successful edit. (8) Don't set the large_folios flag on the inode as we do the allocation ourselves rather than the VM doing it automatically. (9) Mark the inode as being a single object that isn't uploaded to the server. (10) Enable caching on directories. (11) Only set the upload key for writeback for regular files. Notes: (*) We keep the ->release_folio(), ->invalidate_folio() and ->migrate_folio() ops as we set the mapping pointer on the folio. Signed-off-by: David Howells Link: https://lore.kernel.org/r/20241216204124.3752367-22-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

afs: Make afs_init_request() get a key if not given a file

2024-12-20T21:34:06+00:00

In a future patch, AFS directory caching will go through netfslib and this will involve, at times, running on behalf of ->lookup(), which doesn't provide us with a file from which we can get an authentication key. If a file isn't provided, make afs_init_request() get a key from the process's keyrings instead when setting up a read. Signed-off-by: David Howells Link: https://lore.kernel.org/r/20241216204124.3752367-21-dhowells@redhat.com cc: Marc Dionne cc: linux-afs@lists.infradead.org Signed-off-by: Christian Brauner