kernel/linux.git/fs/splice.c, branch v6.19.11

fs/splice.c: trivial fix: pipes -> pipe's

2025-11-25T09:11:16+00:00

Trivial fix. Signed-off-by: Askar Safin Link: https://patch.msgid.link/20251120211316.706725-1-safinaskar@gmail.com Signed-off-by: Christian Brauner

netfs: Fix unbuffered write error handling

2025-08-15T13:56:49+00:00

If all the subrequests in an unbuffered write stream fail, the subrequest collector doesn't update the stream->transferred value and it retains its initial LONG_MAX value. Unfortunately, if all active streams fail, then we take the smallest value of { LONG_MAX, LONG_MAX, ... } as the value to set in wreq->transferred - which is then returned from ->write_iter(). LONG_MAX was chosen as the initial value so that all the streams can be quickly assessed by taking the smallest value of all stream->transferred - but this only works if we've set any of them. Fix this by adding a flag to indicate whether the value in stream->transferred is valid and checking that when we integrate the values. stream->transferred can then be initialised to zero. This was found by running the generic/750 xfstest against cifs with cache=none. It splices data to the target file. Once (if) it has used up all the available scratch space, the writes start failing with ENOSPC. This causes ->write_iter() to fail. However, it was returning wreq->transferred, i.e. LONG_MAX, rather than an error (because it thought the amount transferred was non-zero) and iter_file_splice_write() would then try to clean up that amount of pipe bufferage - leading to an oops when it overran. The kernel log showed: CIFS: VFS: Send error in write = -28 followed by: BUG: kernel NULL pointer dereference, address: 0000000000000008 with: RIP: 0010:iter_file_splice_write+0x3a4/0x520 do_splice+0x197/0x4e0 or: RIP: 0010:pipe_buf_release (include/linux/pipe_fs_i.h:282) iter_file_splice_write (fs/splice.c:755) Also put a warning check into splice to announce if ->write_iter() returned that it had written more than it was asked to. Fixes: 288ace2f57c9 ("netfs: New writeback implementation") Reported-by: Xiaoli Feng Closes: https://bugzilla.kernel.org/show_bug.cgi?id=220445 Signed-off-by: David Howells Link: https://lore.kernel.org/915443.1755207950@warthog.procyon.org.uk cc: Paulo Alcantara cc: Steve French cc: Shyam Prasad N cc: netfs@lists.linux.dev cc: linux-cifs@vger.kernel.org cc: linux-fsdevel@vger.kernel.org cc: stable@vger.kernel.org Signed-off-by: Christian Brauner

splice: remove duplicate noinline from pipe_clear_nowait

2025-04-25T10:11:56+00:00

pipe_clear_nowait has two noinline macros, but we only need one. I checked the whole tree, and this is the only occurrence: $ grep -r "noinline .* noinline" fs/splice.c:static noinline void noinline pipe_clear_nowait(struct file *file) $ Fixes: 0f99fc513ddd ("splice: clear FMODE_NOWAIT on file if splice/vmsplice is used") Signed-off-by: "T.J. Mercier" Link: https://lore.kernel.org/20250423180025.2627670-1-tjmercier@google.com Reviewed-by: Jens Axboe Signed-off-by: Christian Brauner

fs/splice: Use pipe_buf() helper to retrieve pipe buffer

2025-03-10T07:55:05+00:00

Use pipe_buf() helper to retrieve the pipe buffer throughout the file replacing the open-coded the logic. Suggested-by: Oleg Nesterov Signed-off-by: K Prateek Nayak Link: https://lore.kernel.org/r/20250307052919.34542-5-kprateek.nayak@amd.com Signed-off-by: Christian Brauner

fs/pipe: add simpler helpers for common cases

2025-03-07T04:25:35+00:00

The fix to atomically read the pipe head and tail state when not holding the pipe mutex has caused a number of headaches due to the size change of the involved types. It turns out that we don't have _that_ many places that access these fields directly and were affected, but we have more than we strictly should have, because our low-level helper functions have been designed to have intimate knowledge of how the pipes work. And as a result, that random noise of direct 'pipe->head' and 'pipe->tail' accesses makes it harder to pinpoint any actual potential problem spots remaining. For example, we didn't have a "is the pipe full" helper function, but instead had a "given these pipe buffer indexes and this pipe size, is the pipe full". That's because some low-level pipe code does actually want that much more complicated interface. But most other places literally just want a "is the pipe full" helper, and not having it meant that those places ended up being unnecessarily much too aware of this all. It would have been much better if only the very core pipe code that cared had been the one aware of this all. So let's fix it - better late than never. This just introduces the trivial wrappers for "is this pipe full or empty" and to get how many pipe buffers are used, so that instead of writing if (pipe_full(pipe->head, pipe->tail, pipe->max_usage)) the places that literally just want to know if a pipe is full can just say if (pipe_is_full(pipe)) instead. The existing trivial cases were converted with a 'sed' script. This cuts down on the places that access pipe->head and pipe->tail directly outside of the pipe code (and core splice code) quite a lot. The splice code in particular still revels in doing the direct low-level accesses, and the fuse fuse_dev_splice_write() code also seems a bit unnecessarily eager to go very low-level, but it's at least a bit better than it used to be. Signed-off-by: Linus Torvalds

mm: alloc_pages_bulk: rename API

2025-01-26T04:22:31+00:00

The previous commit removed the page_list argument from alloc_pages_bulk_noprof() along with the alloc_pages_bulk_list() function. Now that only the *_array() flavour of the API remains, we can do the following renaming (along with the _noprof() ones): alloc_pages_bulk_array -> alloc_pages_bulk alloc_pages_bulk_array_mempolicy -> alloc_pages_bulk_mempolicy alloc_pages_bulk_array_node -> alloc_pages_bulk_node Link: https://lkml.kernel.org/r/275a3bbc0be20fbe9002297d60045e67ab3d4ada.1734991165.git.luizcap@redhat.com Signed-off-by: Luiz Capitulino Acked-by: David Hildenbrand Cc: Matthew Wilcox (Oracle) Cc: Mel Gorman Cc: Yunsheng Lin Signed-off-by: Andrew Morton

fdget(), more trivial conversions

2024-11-03T06:28:06+00:00

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

convert vmsplice() to CLASS(fd)

2024-11-03T06:28:06+00:00

Irregularity here is fdput() not in the same scope as fdget(); we could just lift it out vmsplice_type() in vmsplice(2), but there's no much point keeping vmsplice_type() separate after that... Reviewed-by: Christian Brauner Signed-off-by: Al Viro

introduce fd_file(), convert all accessors to it.

2024-08-13T02:00:43+00:00

For any changes of struct fd representation we need to turn existing accesses to fields into calls of wrappers. Accesses to struct fd::flags are very few (3 in linux/file.h, 1 in net/socket.c, 3 in fs/overlayfs/file.c and 3 more in explicit initializers). Those can be dealt with in the commit converting to new layout; accesses to struct fd::file are too many for that. This commit converts (almost) all of f.file to fd_file(f). It's not entirely mechanical ('file' is used as a member name more than just in struct fd) and it does not even attempt to distinguish the uses in pointer context from those in boolean context; the latter will be eventually turned into a separate helper (fd_empty()). NOTE: mass conversion to fd_empty(), tempting as it might be, is a bad idea; better do that piecewise in commit that convert from fdget...() to CLASS(...). [conflicts in fs/fhandle.c, kernel/bpf/syscall.c, mm/memcontrol.c caught by git; fs/stat.c one got caught by git grep] [fs/xattr.c conflict] Reviewed-by: Christian Brauner Signed-off-by: Al Viro

remove call_{read,write}_iter() functions

2024-04-15T20:03:25+00:00

These have no clear purpose. This is effectively a revert of commit bb7462b6fd64 ("vfs: use helpers for calling f_op->{read,write}_iter()"). The patch was created with the help of a coccinelle script. Fixes: bb7462b6fd64 ("vfs: use helpers for calling f_op->{read,write}_iter()") Reviewed-by: Christian Brauner Signed-off-by: Miklos Szeredi Signed-off-by: Al Viro