linux/fs/read_write.c, branch v6.16

fs/read_write: make default_llseek() killable

2025-05-15T10:03:12Z

Allows killing processes that are waiting for the inode lock. Signed-off-by: Max Kellermann Link: https://lore.kernel.org/20250513150327.1373061-4-max.kellermann@ionos.com Signed-off-by: Christian Brauner

fs: don't needlessly acquire f_lock

2025-02-21T09:25:32Z

Before 2011 there was no meaningful synchronization between read/readdir/write/seek. Only in commit ef3d0fd27e90 ("vfs: do (nearly) lockless generic_file_llseek") synchronization was added for SEEK_CUR by taking f_lock around vfs_setpos(). Then in 2014 full synchronization between read/readdir/write/seek was added in commit 9c225f2655e3 ("vfs: atomic f_pos accesses as per POSIX") by introducing f_pos_lock for regular files with FMODE_ATOMIC_POS and for directories. At that point taking f_lock became unnecessary for such files. So only acquire f_lock for SEEK_CUR if this isn't a file that would have acquired f_pos_lock if necessary. Link: https://lore.kernel.org/r/20250207-daten-mahlzeit-99d2079864fb@brauner Signed-off-by: Christian Brauner

Merge tag 'pull-fd' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2024-11-18T20:24:06Z

Pull 'struct fd' class updates from Al Viro: "The bulk of struct fd memory safety stuff Making sure that struct fd instances are destroyed in the same scope where they'd been created, getting rid of reassignments and passing them by reference, converting to CLASS(fd{,_pos,_raw}). We are getting very close to having the memory safety of that stuff trivial to verify" * tag 'pull-fd' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (28 commits) deal with the last remaing boolean uses of fd_file() css_set_fork(): switch to CLASS(fd_raw, ...) memcg_write_event_control(): switch to CLASS(fd) assorted variants of irqfd setup: convert to CLASS(fd) do_pollfd(): convert to CLASS(fd) convert do_select() convert vfs_dedupe_file_range(). convert cifs_ioctl_copychunk() convert media_request_get_by_fd() convert spu_run(2) switch spufs_calls_{get,put}() to CLASS() use convert cachestat(2) convert do_preadv()/do_pwritev() fdget(), more trivial conversions fdget(), trivial conversions privcmd_ioeventfd_assign(): don't open-code eventfd_ctx_fdget() o2hb_region_dev_store(): avoid goto around fdget()/fdput() introduce "fd_pos" class, convert fdget_pos() users to it. fdget_raw() users: switch to CLASS(fd_raw) convert vmsplice() to CLASS(fd) ...

fs: Export generic_atomic_write_valid()

2024-11-05T00:14:02Z

The XFS code will need this. Reviewed-by: "Darrick J. Wong" Reviewed-by: Christoph Hellwig Signed-off-by: John Garry Signed-off-by: Darrick J. Wong

convert do_preadv()/do_pwritev()

2024-11-03T06:28:06Z

fdput() can be transposed with add_{r,w}char() and inc_sysc{r,w}(); it's the same story as with do_readv()/do_writev(), only with fdput() instead of fdput_pos(). Reviewed-by: Christian Brauner Signed-off-by: Al Viro

fdget(), more trivial conversions

2024-11-03T06:28:06Z

all failure exits prior to fdget() leave the scope, all matching fdput() are immediately followed by leaving the scope. [xfs_ioc_commit_range() chunk moved here as well] Reviewed-by: Christian Brauner Signed-off-by: Al Viro

fdget(), trivial conversions

2024-11-03T06:28:06Z

fdget() is the first thing done in scope, all matching fdput() are immediately followed by leaving the scope. Reviewed-by: Christian Brauner Signed-off-by: Al Viro

introduce "fd_pos" class, convert fdget_pos() users to it.

2024-11-03T06:28:06Z

fdget_pos() for constructor, fdput_pos() for cleanup, all users of fd..._pos() converted trivially. Reviewed-by: Christian Brauner Signed-off-by: Al Viro

fs/block: Check for IOCB_DIRECT in generic_atomic_write_valid()

2024-10-19T22:48:22Z

Currently FMODE_CAN_ATOMIC_WRITE is set if the bdev can atomic write and the file is open for direct IO. This does not work if the file is not opened for direct IO, yet fcntl(O_DIRECT) is used on the fd later. Change to check for direct IO on a per-IO basis in generic_atomic_write_valid(). Since we want to report -EOPNOTSUPP for non-direct IO for an atomic write, change to return an error code. Relocate the block fops atomic write checks to the common write path, as to catch non-direct IO. Fixes: c34fc6f26ab8 ("fs: Initial atomic write support") Reviewed-by: Christoph Hellwig Reviewed-by: Darrick J. Wong Signed-off-by: John Garry Link: https://lore.kernel.org/r/20241019125113.369994-3-john.g.garry@oracle.com Signed-off-by: Jens Axboe

block/fs: Pass an iocb to generic_atomic_write_valid()

2024-10-19T22:48:21Z

Darrick and Hannes both thought it better that generic_atomic_write_valid() should be passed a struct iocb, and not just the member of that struct which is referenced; see [0] and [1]. I think that makes a more generic and clean API, so make that change. [0] https://lore.kernel.org/linux-block/680ce641-729b-4150-b875-531a98657682@suse.de/ [1] https://lore.kernel.org/linux-xfs/20240620212401.GA3058325@frogsfrogsfrogs/ Fixes: c34fc6f26ab8 ("fs: Initial atomic write support") Suggested-by: Darrick J. Wong Suggested-by: Hannes Reinecke Reviewed-by: Darrick J. Wong Reviewed-by: Christoph Hellwig Signed-off-by: John Garry Link: https://lore.kernel.org/r/20241019125113.369994-2-john.g.garry@oracle.com Signed-off-by: Jens Axboe