Commit Graph

215 Commits

Author SHA1 Message Date
Omar Sandoval
0d24852bd7
iov_iter: fix advancing slot in iter_folioq_get_pages()
iter_folioq_get_pages() decides to advance to the next folioq slot when
it has reached the end of the current folio. However, it is checking
offset, which is the beginning of the current part, instead of
iov_offset, which is adjusted to the end of the current part, so it
doesn't advance the slot when it's supposed to. As a result, on the next
iteration, we'll use the same folio with an out-of-bounds offset and
return an unrelated page.

This manifested as various crashes and other failures in 9pfs in drgn's
VM testing setup and BPF CI.

Fixes: db0aa2e956 ("mm: Define struct folio_queue and ITER_FOLIOQ to handle a sequence of folios")
Link: https://lore.kernel.org/linux-fsdevel/20240923183432.1876750-1-chantr4@gmail.com/
Tested-by: Manu Bretelle <chantr4@gmail.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Link: https://lore.kernel.org/r/cbaf141ba6c0e2e209717d02746584072844841a.1727722269.git.osandov@fb.com
Tested-by: Eduard Zingerman <eddyz87@gmail.com>
Tested-by: Leon Romanovsky <leon@kernel.org>
Tested-by: Joey Gouly <joey.gouly@arm.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-10-01 11:49:57 +02:00
David Howells
db0aa2e956
mm: Define struct folio_queue and ITER_FOLIOQ to handle a sequence of folios
Define a data structure, struct folio_queue, to represent a sequence of
folios and a kernel-internal I/O iterator type, ITER_FOLIOQ, to allow a
list of folio_queue structures to be used to provide a buffer to
iov_iter-taking functions, such as sendmsg and recvmsg.

The folio_queue structure looks like:

	struct folio_queue {
		struct folio_batch	vec;
		u8			orders[PAGEVEC_SIZE];
		struct folio_queue	*next;
		struct folio_queue	*prev;
		unsigned long		marks;
		unsigned long		marks2;
	};

It does not use a list_head so that next and/or prev can be set to NULL at
the ends of the list, allowing iov_iter-handling routines to determine that
they *are* the ends without needing to store a head pointer in the iov_iter
struct.

A folio_batch struct is used to hold the folio pointers which allows the
batch to be passed to batch handling functions.  Two mark bits are
available per slot.  The intention is to use at least one of them to mark
folios that need putting, but that might not be ultimately necessary.
Accessor functions are used to access the slots to do the masking and an
additional accessor function is used to indicate the size of the array.

The order of each folio is also stored in the structure to avoid the need
for iov_iter_advance() and iov_iter_revert() to have to query each folio to
find its size.

With careful barriering, this can be used as an extending buffer with new
folios inserted and new folio_queue structs added without the need for a
lock.  Further, provided we always keep at least one struct in the buffer,
we can also remove consumed folios and consumed structs from the head end
as we without the need for locks.

[Questions/thoughts]

 (1) To manage this, I need a head pointer, a tail pointer, a tail slot
     number (assuming insertion happens at the tail end and the next
     pointers point from head to tail).  Should I put these into a struct
     of their own, say "folio_queue_head" or "rolling_buffer"?

     I will end up with two of these in netfs_io_request eventually, one
     keeping track of the pagecache I'm dealing with for buffered I/O and
     the other to hold a bounce buffer when we need one.

 (2) Should I make the slots {folio,off,len} or bio_vec?

 (3) This is intended to replace ITER_XARRAY eventually.  Using an xarray
     in I/O iteration requires the taking of the RCU read lock, doing
     copying under the RCU read lock, walking the xarray (which may change
     under us), handling retries and dealing with special values.

     The advantage of ITER_XARRAY is that when we're dealing with the
     pagecache directly, we don't need any allocation - but if we're doing
     encrypted comms, there's a good chance we'd be using a bounce buffer
     anyway.

     This will require afs, erofs, cifs, orangefs and fscache to be
     converted to not use this.  afs still uses it for dirs and symlinks;
     some of erofs usages should be easy to change, but there's one which
     won't be so easy; ceph's use via fscache can be fixed by porting ceph
     to netfslib; cifs is using xarray as a bounce buffer - that can be
     moved to use sheaves instead; and orangefs has a similar problem to
     erofs - maybe orangefs could use netfslib?

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Matthew Wilcox <willy@infradead.org>
cc: Jeff Layton <jlayton@kernel.org>
cc: Steve French <sfrench@samba.org>
cc: Ilya Dryomov <idryomov@gmail.com>
cc: Gao Xiang <xiang@kernel.org>
cc: Mike Marshall <hubcap@omnibond.com>
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
cc: linux-mm@kvack.org
cc: linux-afs@lists.infradead.org
cc: linux-cifs@vger.kernel.org
cc: ceph-devel@vger.kernel.org
cc: linux-erofs@lists.ozlabs.org
cc: devel@lists.orangefs.org
Link: https://lore.kernel.org/r/20240814203850.2240469-13-dhowells@redhat.com/ # v2
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-09-12 12:20:21 +02:00
Linus Torvalds
7ea65c89d8 vfs-6.9.misc
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Merge tag 'vfs-6.9.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull misc vfs updates from Christian Brauner:
 "Misc features, cleanups, and fixes for vfs and individual filesystems.

  Features:

   - Support idmapped mounts for hugetlbfs.

   - Add RWF_NOAPPEND flag for pwritev2(). This allows us to fix a bug
     where the passed offset is ignored if the file is O_APPEND. The new
     flag allows a caller to enforce that the offset is honored to
     conform to posix even if the file was opened in append mode.

   - Move i_mmap_rwsem in struct address_space to avoid false sharing
     between i_mmap and i_mmap_rwsem.

   - Convert efs, qnx4, and coda to use the new mount api.

   - Add a generic is_dot_dotdot() helper that's used by various
     filesystems and the VFS code instead of open-coding it multiple
     times.

   - Recently we've added stable offsets which allows stable ordering
     when iterating directories exported through NFS on e.g., tmpfs
     filesystems. Originally an xarray was used for the offset map but
     that caused slab fragmentation issues over time. This switches the
     offset map to the maple tree which has a dense mode that handles
     this scenario a lot better. Includes tests.

   - Finally merge the case-insensitive improvement series Gabriel has
     been working on for a long time. This cleanly propagates case
     insensitive operations through ->s_d_op which in turn allows us to
     remove the quite ugly generic_set_encrypted_ci_d_ops() operations.
     It also improves performance by trying a case-sensitive comparison
     first and then fallback to case-insensitive lookup if that fails.
     This also fixes a bug where overlayfs would be able to be mounted
     over a case insensitive directory which would lead to all sort of
     odd behaviors.

  Cleanups:

   - Make file_dentry() a simple accessor now that ->d_real() is
     simplified because of the backing file work we did the last two
     cycles.

   - Use the dedicated file_mnt_idmap helper in ntfs3.

   - Use smp_load_acquire/store_release() in the i_size_read/write
     helpers and thus remove the hack to handle i_size reads in the
     filemap code.

   - The SLAB_MEM_SPREAD is a nop now. Remove it from various places in
     fs/

   - It's no longer necessary to perform a second built-in initramfs
     unpack call because we retain the contents of the previous
     extraction. Remove it.

   - Now that we have removed various allocators kfree_rcu() always
     works with kmem caches and kmalloc(). So simplify various places
     that only use an rcu callback in order to handle the kmem cache
     case.

   - Convert the pipe code to use a lockdep comparison function instead
     of open-coding the nesting making lockdep validation easier.

   - Move code into fs-writeback.c that was located in a header but can
     be made static as it's only used in that one file.

   - Rewrite the alignment checking iterators for iovec and bvec to be
     easier to read, and also significantly more compact in terms of
     generated code. This saves 270 bytes of text on x86-64 (with
     clang-18) and 224 bytes on arm64 (with gcc-13). In profiles it also
     saves a bit of time for the same workload.

   - Switch various places to use KMEM_CACHE instead of
     kmem_cache_create().

   - Use inode_set_ctime_to_ts() in inode_set_ctime_current()

   - Use kzalloc() in name_to_handle_at() to avoid kernel infoleak.

   - Various smaller cleanups for eventfds.

  Fixes:

   - Fix various comments and typos, and unneeded initializations.

   - Fix stack allocation hack for clang in the select code.

   - Improve dump_mapping() debug code on a best-effort basis.

   - Fix build errors in various selftests.

   - Avoid wrap-around instrumentation in various places.

   - Don't allow user namespaces without an idmapping to be used for
     idmapped mounts.

   - Fix sysv sb_read() call.

   - Fix fallback implementation of the get_name() export operation"

* tag 'vfs-6.9.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (70 commits)
  hugetlbfs: support idmapped mounts
  qnx4: convert qnx4 to use the new mount api
  fs: use inode_set_ctime_to_ts to set inode ctime to current time
  libfs: Drop generic_set_encrypted_ci_d_ops
  ubifs: Configure dentry operations at dentry-creation time
  f2fs: Configure dentry operations at dentry-creation time
  ext4: Configure dentry operations at dentry-creation time
  libfs: Add helper to choose dentry operations at mount-time
  libfs: Merge encrypted_ci_dentry_ops and ci_dentry_ops
  fscrypt: Drop d_revalidate once the key is added
  fscrypt: Drop d_revalidate for valid dentries during lookup
  fscrypt: Factor out a helper to configure the lookup dentry
  ovl: Always reject mounting over case-insensitive directories
  libfs: Attempt exact-match comparison first during casefolded lookup
  efs: remove SLAB_MEM_SPREAD flag usage
  jfs: remove SLAB_MEM_SPREAD flag usage
  minix: remove SLAB_MEM_SPREAD flag usage
  openpromfs: remove SLAB_MEM_SPREAD flag usage
  proc: remove SLAB_MEM_SPREAD flag usage
  qnx6: remove SLAB_MEM_SPREAD flag usage
  ...
2024-03-11 09:38:17 -07:00
Linus Torvalds
a50026bdb8
iov_iter: get rid of 'copy_mc' flag
This flag is only set by one single user: the magical core dumping code
that looks up user pages one by one, and then writes them out using
their kernel addresses (by using a BVEC_ITER).

That actually ends up being a huge problem, because while we do use
copy_mc_to_kernel() for this case and it is able to handle the possible
machine checks involved, nothing else is really ready to handle the
failures caused by the machine check.

In particular, as reported by Tong Tiangen, we don't actually support
fault_in_iov_iter_readable() on a machine check area.

As a result, the usual logic for writing things to a file under a
filesystem lock, which involves doing a copy with page faults disabled
and then if that fails trying to fault pages in without holding the
locks with fault_in_iov_iter_readable() does not work at all.

We could decide to always just make the MC copy "succeed" (and filling
the destination with zeroes), and that would then create a core dump
file that just ignores any machine checks.

But honestly, this single special case has been problematic before, and
means that all the normal iov_iter code ends up slightly more complex
and slower.

See for example commit c9eec08bac ("iov_iter: Don't deal with
iter->copy_mc in memcpy_from_iter_mc()") where David Howells
re-organized the code just to avoid having to check the 'copy_mc' flags
inside the inner iov_iter loops.

So considering that we have exactly one user, and that one user is a
non-critical special case that doesn't actually ever trigger in real
life (Tong found this with manual error injection), the sane solution is
to just decide that the onus on handling the machine check lines on that
user instead.

Ergo, do the copy_mc_to_kernel() in the core dump logic itself, copying
the user data to a stable kernel page before writing it out.

Fixes: f1982740f5 ("iov_iter: Convert iterate*() to inline funcs")
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Tong Tiangen <tongtiangen@huawei.com>
Link: https://lore.kernel.org/r/20240305133336.3804360-1-tongtiangen@huawei.com
Link: https://lore.kernel.org/all/4e80924d-9c85-f13a-722a-6a5d2b1c225a@huawei.com/
Tested-by: David Howells <dhowells@redhat.com>
Reviewed-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Reported-by: Tong Tiangen <tongtiangen@huawei.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-03-06 10:52:12 +01:00
Kees Cook
bd8c239c05 iov_iter: Avoid wrap-around instrumentation in copy_compat_iovec_from_user()
The loop counter "i" in copy_compat_iovec_from_user() is an int, but
because the nr_segs argument is unsigned long, the signed overflow
sanitizer got worried "i" could wrap around. Instead of making "i" an
unsigned long (which may enlarge the type size), switch both nr_segs
and i to u32. There is no truncation with nr_segs since it is never
larger than UIO_MAXIOV anyway. This keeps sanitizer instrumentation[1]
out of a UACCESS path:

vmlinux.o: warning: objtool: copy_compat_iovec_from_user+0xa9: call to __ubsan_handle_add_overflow() with UACCESS enabled

Link: https://github.com/KSPP/linux/issues/26 [1]
Cc: Christian Brauner <brauner@kernel.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20240129183729.work.991-kees@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-02-02 13:11:49 +01:00
Jens Axboe
2263639f96 iov_iter: streamline iovec/bvec alignment iteration
Rewrite the alignment checking iterators for iovec and bvec to be easier
to read, and also significantly more compact in terms of generated code.
This saves 270 bytes of text on x86-64 for me (with clang-18) and 224
bytes on arm64 (with gcc-13).

In profiles, also saves a bit of time as well for the same workload:

     0.81%     -0.18%  [kernel.vmlinux]  [k] iov_iter_aligned_bvec
     0.48%     -0.09%  [kernel.vmlinux]  [k] iov_iter_is_aligned

which is a nice side benefit as well.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
Link: https://lore.kernel.org/r/544b31f7-6d4b-42f5-a544-1420501f081f@kernel.dk
Reviewed-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

v2: do the other half of the iterators too, as suggested by Keith.
    This further saves some text.
2024-01-25 17:14:44 +01:00
Linus Torvalds
5db8752c3b vfs-6.8.iov_iter
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Merge tag 'vfs-6.8.iov_iter' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull vfs iov_iter cleanups from Christian Brauner:
 "This contains a minor cleanup. The patches drop an unused argument
  from import_single_range() allowing to replace import_single_range()
  with import_ubuf() and dropping import_single_range() completely"

* tag 'vfs-6.8.iov_iter' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  iov_iter: replace import_single_range() with import_ubuf()
  iov_iter: remove unused 'iov' argument from import_single_range()
2024-01-08 11:43:04 -08:00
Jens Axboe
9fd7874c0e
iov_iter: replace import_single_range() with import_ubuf()
With the removal of the 'iov' argument to import_single_range(), the two
functions are now fully identical. Convert the import_single_range()
callers to import_ubuf(), and remove the former fully.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
Link: https://lore.kernel.org/r/20231204174827.1258875-3-axboe@kernel.dk
Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-12-05 11:57:37 +01:00
Jens Axboe
6ac805d138
iov_iter: remove unused 'iov' argument from import_single_range()
It is entirely unused, just get rid of it.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
Link: https://lore.kernel.org/r/20231204174827.1258875-2-axboe@kernel.dk
Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-12-05 11:57:34 +01:00
Omar Sandoval
fe2c34bab6 iov_iter: fix copy_page_to_iter_nofault()
The recent conversion to inline functions made two mistakes:

1. It tries to copy the full amount requested (bytes), not just what's
   available in the kmap'd page (n).
2. It's not applying the offset in the first page.

Note that copy_page_to_iter_nofault() is only used by /proc/kcore. This
was detected by drgn's test suite.

Fixes: f1982740f5 ("iov_iter: Convert iterate*() to inline funcs")
Signed-off-by: Omar Sandoval <osandov@fb.com>
Link: https://lore.kernel.org/r/c1616e06b5248013cbbb1881bb4fef85a7a69ccb.1700257019.git.osandov@fb.com
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-11-18 16:42:07 +01:00
David Howells
b5f0e20f44
iov_iter, net: Move hash_and_copy_to_iter() to net/
Move hash_and_copy_to_iter() to be with its only caller in networking code.

Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/r/20230925120309.1731676-13-dhowells@redhat.com
cc: Alexander Viro <viro@zeniv.linux.org.uk>
cc: Jens Axboe <axboe@kernel.dk>
cc: Christoph Hellwig <hch@lst.de>
cc: Christian Brauner <christian@brauner.io>
cc: Matthew Wilcox <willy@infradead.org>
cc: Linus Torvalds <torvalds@linux-foundation.org>
cc: David Laight <David.Laight@ACULAB.COM>
cc: "David S. Miller" <davem@davemloft.net>
cc: Eric Dumazet <edumazet@google.com>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Paolo Abeni <pabeni@redhat.com>
cc: linux-block@vger.kernel.org
cc: linux-fsdevel@vger.kernel.org
cc: linux-mm@kvack.org
cc: netdev@vger.kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-10-09 09:35:14 +02:00
David Howells
6d0d419914
iov_iter, net: Move csum_and_copy_to/from_iter() to net/
Move csum_and_copy_to/from_iter() to net code now that the iteration
framework can be #included.

Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/r/20230925120309.1731676-10-dhowells@redhat.com
cc: Alexander Viro <viro@zeniv.linux.org.uk>
cc: Jens Axboe <axboe@kernel.dk>
cc: Christoph Hellwig <hch@lst.de>
cc: Christian Brauner <christian@brauner.io>
cc: Matthew Wilcox <willy@infradead.org>
cc: Linus Torvalds <torvalds@linux-foundation.org>
cc: David Laight <David.Laight@ACULAB.COM>
cc: "David S. Miller" <davem@davemloft.net>
cc: Eric Dumazet <edumazet@google.com>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Paolo Abeni <pabeni@redhat.com>
cc: linux-block@vger.kernel.org
cc: linux-fsdevel@vger.kernel.org
cc: linux-mm@kvack.org
cc: netdev@vger.kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-10-09 09:35:14 +02:00
David Howells
c9eec08bac
iov_iter: Don't deal with iter->copy_mc in memcpy_from_iter_mc()
iter->copy_mc is only used with a bvec iterator and only by
dump_emit_page() in fs/coredump.c so rather than handle this in
memcpy_from_iter_mc() where it is checked repeatedly by _copy_from_iter()
and copy_page_from_iter_atomic(),

Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/r/20230925120309.1731676-9-dhowells@redhat.com
cc: Alexander Viro <viro@zeniv.linux.org.uk>
cc: Jens Axboe <axboe@kernel.dk>
cc: Christoph Hellwig <hch@lst.de>
cc: Christian Brauner <christian@brauner.io>
cc: Matthew Wilcox <willy@infradead.org>
cc: Linus Torvalds <torvalds@linux-foundation.org>
cc: David Laight <David.Laight@ACULAB.COM>
cc: linux-block@vger.kernel.org
cc: linux-fsdevel@vger.kernel.org
cc: linux-mm@kvack.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-10-09 09:35:14 +02:00
David Howells
f1982740f5
iov_iter: Convert iterate*() to inline funcs
Convert the iov_iter iteration macros to inline functions to make the code
easier to follow.

The functions are marked __always_inline as we don't want to end up with
indirect calls in the code.  This, however, leaves dealing with ->copy_mc
in an awkard situation since the step function (memcpy_from_iter_mc())
needs to test the flag in the iterator, but isn't passed the iterator.
This will be dealt with in a follow-up patch.

The variable names in the per-type iterator functions have been harmonised
as much as possible and made clearer as to the variable purpose.

The iterator functions are also moved to a header file so that other
operations that need to scan over an iterator can be added.  For instance,
the rbd driver could use this to scan a buffer to see if it is all zeros
and libceph could use this to generate a crc.

Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/r/3710261.1691764329@warthog.procyon.org.uk/ # v1
Link: https://lore.kernel.org/r/855.1692047347@warthog.procyon.org.uk/ # v2
Link: https://lore.kernel.org/r/20230816120741.534415-1-dhowells@redhat.com/ # v3
Link: https://lore.kernel.org/r/20230925120309.1731676-8-dhowells@redhat.com
cc: Alexander Viro <viro@zeniv.linux.org.uk>
cc: Jens Axboe <axboe@kernel.dk>
cc: Christoph Hellwig <hch@lst.de>
cc: Christian Brauner <christian@brauner.io>
cc: Matthew Wilcox <willy@infradead.org>
cc: Linus Torvalds <torvalds@linux-foundation.org>
cc: David Laight <David.Laight@ACULAB.COM>
cc: linux-block@vger.kernel.org
cc: linux-fsdevel@vger.kernel.org
cc: linux-mm@kvack.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-09-25 14:30:28 +02:00
David Howells
f1b4cb650b
iov_iter: Derive user-backedness from the iterator type
Use the iterator type to determine whether an iterator is user-backed or
not rather than using a special flag for it.  Now that ITER_UBUF and
ITER_IOVEC are 0 and 1, they can be checked with a single comparison.

Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/r/20230925120309.1731676-7-dhowells@redhat.com
cc: Alexander Viro <viro@zeniv.linux.org.uk>
cc: Jens Axboe <axboe@kernel.dk>
cc: Christoph Hellwig <hch@lst.de>
cc: Christian Brauner <christian@brauner.io>
cc: Matthew Wilcox <willy@infradead.org>
cc: Linus Torvalds <torvalds@linux-foundation.org>
cc: David Laight <David.Laight@ACULAB.COM>
cc: linux-block@vger.kernel.org
cc: linux-fsdevel@vger.kernel.org
cc: linux-mm@kvack.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-09-25 14:30:28 +02:00
David Howells
f741bd7178 iov_iter: Fix iov_iter_extract_pages() with zero-sized entries
iov_iter_extract_pages() doesn't correctly handle skipping over initial
zero-length entries in ITER_KVEC and ITER_BVEC-type iterators.

The problem is that it accidentally reduces maxsize to 0 when it
skipping and thus runs to the end of the array and returns 0.

Fix this by sticking the calculated size-to-copy in a new variable
rather than back in maxsize.

Fixes: 7d58fe7310 ("iov_iter: Add a function to extract a page list from an iterator")
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: David Hildenbrand <david@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2023-09-09 15:11:49 -07:00
Linus Torvalds
4fb0dacb78 sound updates for 6.6-rc1
We've received a fairly wide range of changes at this time, including
 for ALSA and ASoC core, but all of them are rather small changes.
 
 Here are some highlights:
 
 ALSA / ASoC Core:
 - Fixes of inconsistent locking around control API helpers
 - A few new control API functions and cleanups
 - Workarounds for potential UAFs by delayed kobj releases
 - Unified PCM copy ops with iov_iter
 - Continued efforts for ASoC API cleanups
 
 ASoC:
 - An adaptor to allow use of IIO DACs and ADCs in ASoC which pulls in
   some IIO changes
 - Create a library function for intlog10() and use it in the NAU8825
   driver
 - Convert drivers to use the more modern maple tree register cache
 - Lots of work on the SOF framework, AMD and Intel drivers, including a
   lot of cleanup and new device support
 - Standardization of the presentation of jacks from drivers
 - Provision of some generic sound card DT properties
 - Support for AMD Van Gogh, AMD machines with MAX98388 and NAU8821,
   AWInic AW88261, Cirrus Logic CS35L36 and CS42L43, various Intel
   platforms including AVS machines with ES8336 and RT5663, Mediatek
   MT7986, NXP i.MX93, RealTek RT1017 and StarFive JH7110
 
 Others:
 - New test coverage including ASoC and topology tests in KUnit;
   this also involves enabling UML builds of ALSA since that's the
   default KUnit test environment which pulls in the addition of some
   stubs to the driver
 - More enhancement of pcmtest driver
 - A few fixes / enhancements of MIDI 2.0 UMP core
 - Using PCI definitions in allover HD-audio code
 - Support for Cirrus CS35L56 and TI TAS2781 HD-audio sub-codecs
 - CS35L41 HD-audio sub-codec improvements
 - Continued emu10k1 improvements
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Merge tag 'sound-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound

Pull sound updates from Takashi Iwai:
 "We've received a fairly wide range of changes at this time, including
  for ALSA and ASoC core, but all of them are rather small changes.

  Here are some highlights:

  ALSA / ASoC Core:
   - Fixes of inconsistent locking around control API helpers
   - A few new control API functions and cleanups
   - Workarounds for potential UAFs by delayed kobj releases
   - Unified PCM copy ops with iov_iter
   - Continued efforts for ASoC API cleanups

  ASoC:
   - An adaptor to allow use of IIO DACs and ADCs in ASoC which pulls in
     some IIO changes
   - Create a library function for intlog10() and use it in the NAU8825
     driver
   - Convert drivers to use the more modern maple tree register cache
   - Lots of work on the SOF framework, AMD and Intel drivers, including
     a lot of cleanup and new device support
   - Standardization of the presentation of jacks from drivers
   - Provision of some generic sound card DT properties
   - Support for AMD Van Gogh, AMD machines with MAX98388 and NAU8821,
     AWInic AW88261, Cirrus Logic CS35L36 and CS42L43, various Intel
     platforms including AVS machines with ES8336 and RT5663, Mediatek
     MT7986, NXP i.MX93, RealTek RT1017 and StarFive JH7110

  Others:
   - New test coverage including ASoC and topology tests in KUnit; this
     also involves enabling UML builds of ALSA since that's the default
     KUnit test environment which pulls in the addition of some stubs to
     the driver
   - More enhancement of pcmtest driver
   - A few fixes / enhancements of MIDI 2.0 UMP core
   - Using PCI definitions in allover HD-audio code
   - Support for Cirrus CS35L56 and TI TAS2781 HD-audio sub-codecs
   - CS35L41 HD-audio sub-codec improvements
   - Continued emu10k1 improvements"

* tag 'sound-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: (693 commits)
  ALSA: pcm: Fix missing fixup call in compat hw_refine ioctl
  ASoC: dwc: i2s: Fix unused functions
  ALSA: usb-audio: Don't try to submit URBs after disconnection
  ALSA: emu10k1: add separate documentation for E-MU cards
  ALSA: emu10k1: more documentation updates
  ALSA: emu10k1: de-duplicate audigy-mixer.rst vs. sb-live-mixer.rst
  ALSA: ump: Fix -Wformat-truncation warnings
  ALSA: hda: Add missing dependency on CONFIG_EFI for Cirrus/TI sub-codecs
  ALSA: doc: Fix missing backquote in midi-2.0.rst
  ALSA: hda/realtek: Add quirk for mute LEDs on HP ENVY x360 15-eu0xxx
  ALSA: hda/tas2781: Switch back to use struct i2c_driver's .probe()
  ASoC: soc-core.c: Do not error if a DAI link component is not found
  ASoC: codecs: Fix error code in aw88261_i2c_probe()
  ASoC: audio-graph-card.c: move audio_graph_parse_of()
  ASoC: cs42l43: Use new-style PM runtime macros
  ALSA: documentation: Add description for USB MIDI 2.0 gadget driver
  ALSA: ump: Don't create unused substreams for static blocks
  ALSA: ump: Fill group names for legacy rawmidi substreams
  ALSA: usb-audio: Attach legacy rawmidi after probing all UMP EPs
  ALSA: ac97: Fix possible error value of *rac97
  ...
2023-08-30 13:45:05 -07:00
Takashi Iwai
70e969eb23 iov_iter: Export import_ubuf()
Export import_ubuf() to be used in sound subsystem for generic memory
handling as Linus suggested.  It's used for constructing an iov_iter
of a single segment user-space copy for PCM data.

Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Link: https://lore.kernel.org/r/CAHk-=wh-mUL6mp4chAc6E_UjwpPLyCPRCJK+iB4ZMD2BqjwGHA@mail.gmail.com
Link: https://lore.kernel.org/r/20230815190136.8987-2-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2023-08-18 12:18:15 +02:00
Matthew Wilcox (Oracle)
1b0306981e iov_iter: Add copy_folio_from_iter_atomic()
Add a folio wrapper around copy_page_from_iter_atomic().

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2023-07-24 18:03:58 -04:00
Matthew Wilcox (Oracle)
908a1ad894 iov_iter: Handle compound highmem pages in copy_page_from_iter_atomic()
copy_page_from_iter_atomic() already handles !highmem compound
pages correctly, but if we are passed a highmem compound page,
each base page needs to be mapped & unmapped individually.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kent Overstreet <kent.overstreet@linux.dev>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Tested-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-07-24 18:03:43 -04:00
Matthew Wilcox (Oracle)
f7f9a0c873 iov_iter: Map the page later in copy_page_from_iter_atomic()
Remove a couple of calls to kunmap_atomic() in the rare error cases.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kent Overstreet <kent.overstreet@linux.dev>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
2023-07-24 18:03:43 -04:00
Peter Zijlstra
719a937b70 iov_iter: Mark copy_iovec_from_user() noclone
Extend commit 50f9a76ef1 ("iov_iter: Mark
copy_compat_iovec_from_user() noinline") to also cover
copy_iovec_from_user(). Different compiler versions cause the same
problem on different functions.

lib/iov_iter.o: warning: objtool: .altinstr_replacement+0x1f: redundant UACCESS disable
lib/iov_iter.o: warning: objtool: iovec_from_user+0x84: call to copy_iovec_from_user.part.0() with UACCESS enabled
lib/iov_iter.o: warning: objtool: __import_iovec+0x143: call to copy_iovec_from_user.part.0() with UACCESS enabled

Fixes: 50f9a76ef1 ("iov_iter: Mark copy_compat_iovec_from_user() noinline")
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lkml.kernel.org/r/20230616124354.GD4253@hirez.programming.kicks-ass.net
2023-07-10 09:52:28 +02:00
Christoph Hellwig
84bd06c632 iov_iter: remove iov_iter_get_pages and iov_iter_get_pages_alloc
Now that the direct I/O helpers have switched to use
iov_iter_extract_pages, these helpers are unused.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Reviewed-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/r/20230614140341.521331-5-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-06-16 10:08:09 -06:00
David Howells
3fc40265ae iov_iter: Kill ITER_PIPE
The ITER_PIPE-type iterator was only used by generic_file_splice_read() and
that has been replaced and removed.  This leaves ITER_PIPE unused - so
remove it too.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christian Brauner <brauner@kernel.org>
cc: Jens Axboe <axboe@kernel.dk>
cc: Al Viro <viro@zeniv.linux.org.uk>
cc: David Hildenbrand <david@redhat.com>
cc: John Hubbard <jhubbard@nvidia.com>
cc: linux-mm@kvack.org
cc: linux-block@vger.kernel.org
cc: linux-fsdevel@vger.kernel.org
Link: https://lore.kernel.org/r/20230522135018.2742245-31-dhowells@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-05-24 08:42:17 -06:00
Kefeng Wang
245f092268 mm: hwpoison: coredump: support recovery from dump_user_range()
dump_user_range() is used to copy the user page to a coredump file, but if
a hardware memory error occurred during copy, which called from
__kernel_write_iter() in dump_user_range(), it crashes,

  CPU: 112 PID: 7014 Comm: mca-recover Not tainted 6.3.0-rc2 #425

  pc : __memcpy+0x110/0x260
  lr : _copy_from_iter+0x3bc/0x4c8
  ...
  Call trace:
   __memcpy+0x110/0x260
   copy_page_from_iter+0xcc/0x130
   pipe_write+0x164/0x6d8
   __kernel_write_iter+0x9c/0x210
   dump_user_range+0xc8/0x1d8
   elf_core_dump+0x308/0x368
   do_coredump+0x2e8/0xa40
   get_signal+0x59c/0x788
   do_signal+0x118/0x1f8
   do_notify_resume+0xf0/0x280
   el0_da+0x130/0x138
   el0t_64_sync_handler+0x68/0xc0
   el0t_64_sync+0x188/0x190

Generally, the '->write_iter' of file ops will use copy_page_from_iter()
and copy_page_from_iter_atomic(), change memcpy() to copy_mc_to_kernel()
in both of them to handle #MC during source read, which stop coredump
processing and kill the task instead of kernel panic, but the source
address may not always a user address, so introduce a new copy_mc flag in
struct iov_iter{} to indicate that the iter could do a safe memory copy,
also introduce the helpers to set/cleck the flag, for now, it's only used
in coredump's dump_user_range(), but it could expand to any other
scenarios to fix the similar issue.

Link: https://lkml.kernel.org/r/20230417045323.11054-1-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: Tong Tiangen <tongtiangen@huawei.com>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-05-02 17:21:50 -07:00
Linus Torvalds
7fa8a8ee94 - Nick Piggin's "shoot lazy tlbs" series, to improve the peformance of
switching from a user process to a kernel thread.
 
 - More folio conversions from Kefeng Wang, Zhang Peng and Pankaj Raghav.
 
 - zsmalloc performance improvements from Sergey Senozhatsky.
 
 - Yue Zhao has found and fixed some data race issues around the
   alteration of memcg userspace tunables.
 
 - VFS rationalizations from Christoph Hellwig:
 
   - removal of most of the callers of write_one_page().
 
   - make __filemap_get_folio()'s return value more useful
 
 - Luis Chamberlain has changed tmpfs so it no longer requires swap
   backing.  Use `mount -o noswap'.
 
 - Qi Zheng has made the slab shrinkers operate locklessly, providing
   some scalability benefits.
 
 - Keith Busch has improved dmapool's performance, making part of its
   operations O(1) rather than O(n).
 
 - Peter Xu adds the UFFD_FEATURE_WP_UNPOPULATED feature to userfaultd,
   permitting userspace to wr-protect anon memory unpopulated ptes.
 
 - Kirill Shutemov has changed MAX_ORDER's meaning to be inclusive rather
   than exclusive, and has fixed a bunch of errors which were caused by its
   unintuitive meaning.
 
 - Axel Rasmussen give userfaultfd the UFFDIO_CONTINUE_MODE_WP feature,
   which causes minor faults to install a write-protected pte.
 
 - Vlastimil Babka has done some maintenance work on vma_merge():
   cleanups to the kernel code and improvements to our userspace test
   harness.
 
 - Cleanups to do_fault_around() by Lorenzo Stoakes.
 
 - Mike Rapoport has moved a lot of initialization code out of various
   mm/ files and into mm/mm_init.c.
 
 - Lorenzo Stoakes removd vmf_insert_mixed_prot(), which was added for
   DRM, but DRM doesn't use it any more.
 
 - Lorenzo has also coverted read_kcore() and vread() to use iterators
   and has thereby removed the use of bounce buffers in some cases.
 
 - Lorenzo has also contributed further cleanups of vma_merge().
 
 - Chaitanya Prakash provides some fixes to the mmap selftesting code.
 
 - Matthew Wilcox changes xfs and afs so they no longer take sleeping
   locks in ->map_page(), a step towards RCUification of pagefaults.
 
 - Suren Baghdasaryan has improved mmap_lock scalability by switching to
   per-VMA locking.
 
 - Frederic Weisbecker has reworked the percpu cache draining so that it
   no longer causes latency glitches on cpu isolated workloads.
 
 - Mike Rapoport cleans up and corrects the ARCH_FORCE_MAX_ORDER Kconfig
   logic.
 
 - Liu Shixin has changed zswap's initialization so we no longer waste a
   chunk of memory if zswap is not being used.
 
 - Yosry Ahmed has improved the performance of memcg statistics flushing.
 
 - David Stevens has fixed several issues involving khugepaged,
   userfaultfd and shmem.
 
 - Christoph Hellwig has provided some cleanup work to zram's IO-related
   code paths.
 
 - David Hildenbrand has fixed up some issues in the selftest code's
   testing of our pte state changing.
 
 - Pankaj Raghav has made page_endio() unneeded and has removed it.
 
 - Peter Xu contributed some rationalizations of the userfaultfd
   selftests.
 
 - Yosry Ahmed has fixed an issue around memcg's page recalim accounting.
 
 - Chaitanya Prakash has fixed some arm-related issues in the
   selftests/mm code.
 
 - Longlong Xia has improved the way in which KSM handles hwpoisoned
   pages.
 
 - Peter Xu fixes a few issues with uffd-wp at fork() time.
 
 - Stefan Roesch has changed KSM so that it may now be used on a
   per-process and per-cgroup basis.
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Merge tag 'mm-stable-2023-04-27-15-30' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull MM updates from Andrew Morton:

 - Nick Piggin's "shoot lazy tlbs" series, to improve the peformance of
   switching from a user process to a kernel thread.

 - More folio conversions from Kefeng Wang, Zhang Peng and Pankaj
   Raghav.

 - zsmalloc performance improvements from Sergey Senozhatsky.

 - Yue Zhao has found and fixed some data race issues around the
   alteration of memcg userspace tunables.

 - VFS rationalizations from Christoph Hellwig:
     - removal of most of the callers of write_one_page()
     - make __filemap_get_folio()'s return value more useful

 - Luis Chamberlain has changed tmpfs so it no longer requires swap
   backing. Use `mount -o noswap'.

 - Qi Zheng has made the slab shrinkers operate locklessly, providing
   some scalability benefits.

 - Keith Busch has improved dmapool's performance, making part of its
   operations O(1) rather than O(n).

 - Peter Xu adds the UFFD_FEATURE_WP_UNPOPULATED feature to userfaultd,
   permitting userspace to wr-protect anon memory unpopulated ptes.

 - Kirill Shutemov has changed MAX_ORDER's meaning to be inclusive
   rather than exclusive, and has fixed a bunch of errors which were
   caused by its unintuitive meaning.

 - Axel Rasmussen give userfaultfd the UFFDIO_CONTINUE_MODE_WP feature,
   which causes minor faults to install a write-protected pte.

 - Vlastimil Babka has done some maintenance work on vma_merge():
   cleanups to the kernel code and improvements to our userspace test
   harness.

 - Cleanups to do_fault_around() by Lorenzo Stoakes.

 - Mike Rapoport has moved a lot of initialization code out of various
   mm/ files and into mm/mm_init.c.

 - Lorenzo Stoakes removd vmf_insert_mixed_prot(), which was added for
   DRM, but DRM doesn't use it any more.

 - Lorenzo has also coverted read_kcore() and vread() to use iterators
   and has thereby removed the use of bounce buffers in some cases.

 - Lorenzo has also contributed further cleanups of vma_merge().

 - Chaitanya Prakash provides some fixes to the mmap selftesting code.

 - Matthew Wilcox changes xfs and afs so they no longer take sleeping
   locks in ->map_page(), a step towards RCUification of pagefaults.

 - Suren Baghdasaryan has improved mmap_lock scalability by switching to
   per-VMA locking.

 - Frederic Weisbecker has reworked the percpu cache draining so that it
   no longer causes latency glitches on cpu isolated workloads.

 - Mike Rapoport cleans up and corrects the ARCH_FORCE_MAX_ORDER Kconfig
   logic.

 - Liu Shixin has changed zswap's initialization so we no longer waste a
   chunk of memory if zswap is not being used.

 - Yosry Ahmed has improved the performance of memcg statistics
   flushing.

 - David Stevens has fixed several issues involving khugepaged,
   userfaultfd and shmem.

 - Christoph Hellwig has provided some cleanup work to zram's IO-related
   code paths.

 - David Hildenbrand has fixed up some issues in the selftest code's
   testing of our pte state changing.

 - Pankaj Raghav has made page_endio() unneeded and has removed it.

 - Peter Xu contributed some rationalizations of the userfaultfd
   selftests.

 - Yosry Ahmed has fixed an issue around memcg's page recalim
   accounting.

 - Chaitanya Prakash has fixed some arm-related issues in the
   selftests/mm code.

 - Longlong Xia has improved the way in which KSM handles hwpoisoned
   pages.

 - Peter Xu fixes a few issues with uffd-wp at fork() time.

 - Stefan Roesch has changed KSM so that it may now be used on a
   per-process and per-cgroup basis.

* tag 'mm-stable-2023-04-27-15-30' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (369 commits)
  mm,unmap: avoid flushing TLB in batch if PTE is inaccessible
  shmem: restrict noswap option to initial user namespace
  mm/khugepaged: fix conflicting mods to collapse_file()
  sparse: remove unnecessary 0 values from rc
  mm: move 'mmap_min_addr' logic from callers into vm_unmapped_area()
  hugetlb: pte_alloc_huge() to replace huge pte_alloc_map()
  maple_tree: fix allocation in mas_sparse_area()
  mm: do not increment pgfault stats when page fault handler retries
  zsmalloc: allow only one active pool compaction context
  selftests/mm: add new selftests for KSM
  mm: add new KSM process and sysfs knobs
  mm: add new api to enable ksm per process
  mm: shrinkers: fix debugfs file permissions
  mm: don't check VMA write permissions if the PTE/PMD indicates write permissions
  migrate_pages_batch: fix statistics for longterm pin retry
  userfaultfd: use helper function range_in_vma()
  lib/show_mem.c: use for_each_populated_zone() simplify code
  mm: correct arg in reclaim_pages()/reclaim_clean_pages_from_list()
  fs/buffer: convert create_page_buffers to folio_create_buffers
  fs/buffer: add folio_create_empty_buffers helper
  ...
2023-04-27 19:42:02 -07:00
Linus Torvalds
487c20b016 iov: improve copy_iovec_from_user() code generation
Use the same pattern as the compat version of this code does: instead of
copying the whole array to a kernel buffer and then having a separate
phase of verifying it, just do it one entry at a time, verifying as you
go.

On Jens' /dev/zero readv() test this improves performance by ~6%.

[ This was obviously triggered by Jens' ITER_UBUF updates series ]

Reported-and-tested-by: Jens Axboe <axboe@kernel.dk>
Link: https://lore.kernel.org/all/de35d11d-bce7-e976-7372-1f2caf417103@kernel.dk/
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2023-04-24 10:37:17 -07:00
Josh Poimboeuf
50f9a76ef1 iov_iter: Mark copy_compat_iovec_from_user() noinline
After commit 6376ce56feb6 ("iov_iter: import single vector iovecs as
ITER_UBUF"), GCC does an inter-procedural compiler optimization which
moves the user_access_begin() out of copy_compat_iovec_from_user() and
into its callers:

  lib/iov_iter.o: warning: objtool: .altinstr_replacement+0x0: redundant UACCESS disable
  lib/iov_iter.o: warning: objtool: iovec_from_user.part.0+0xc7: call to copy_compat_iovec_from_user.part.0() with UACCESS enabled
  lib/iov_iter.o: warning: objtool: __import_iovec+0x21d: call to copy_compat_iovec_from_user.part.0() with UACCESS enabled

Enforce the "no UACCESS enable across function boundaries" rule by
disabling cloning for copy_compat_iovec_from_user().

Fixes: 6376ce56feb6 ("iov_iter: import single vector iovecs as ITER_UBUF")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
https://lkml.kernel.org/lkml/20230327120017.6bb826d7@canb.auug.org.au
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Tested-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-04-12 10:46:48 -06:00
Lorenzo Stoakes
4f80818b4a iov_iter: add copy_page_to_iter_nofault()
Provide a means to copy a page to user space from an iterator, aborting if
a page fault would occur.  This supports compound pages, but may be passed
a tail page with an offset extending further into the compound page, so we
cannot pass a folio.

This allows for this function to be called from atomic context and _try_
to user pages if they are faulted in, aborting if not.

The function does not use _copy_to_iter() in order to not specify
might_fault(), this is similar to copy_page_from_iter_atomic().

This is being added in order that an iteratable form of vread() can be
implemented while holding spinlocks.

Link: https://lkml.kernel.org/r/19734729defb0f498a76bdec1bef3ac48a3af3e8.1679511146.git.lstoakes@gmail.com
Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com>
Reviewed-by: Baoquan He <bhe@redhat.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Liu Shixin <liushixin2@huawei.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-04-05 19:42:57 -07:00
Jens Axboe
3b2deb0e46 iov_iter: import single vector iovecs as ITER_UBUF
Add a special case to __import_iovec(), which imports a single segment
iovec as an ITER_UBUF rather than an ITER_IOVEC. ITER_UBUF is cheaper
to iterate than ITER_IOVEC, and for a single segment iovec, there's no
point in using a segmented iterator.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-03-30 08:12:29 -06:00
Jens Axboe
e03ad4ee27 iov_iter: convert import_single_range() to ITER_UBUF
Since we're just importing a single vector, we don't have to turn it
into an ITER_IOVEC. Instead turn it into an ITER_UBUF, which is cheaper
to iterate.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-03-30 08:12:29 -06:00
Jens Axboe
de4f5fed3f iov_iter: add iter_iovec() helper
This returns a pointer to the current iovec entry in the iterator. Only
useful with ITER_IOVEC right now, but it prepares us to treat ITER_UBUF
and ITER_IOVEC identically for the first segment.

Rename struct iov_iter->iov to iov_iter->__iov to find any potentially
troublesome spots, and also to prevent anyone from adding new code that
accesses iter->iov directly.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-03-30 08:12:29 -06:00
Linus Torvalds
307e14c039 46 fs/cifs (smb3 client) changesets, 37 in fs/cifs and 9 for related helper functions and cleanup outside from Dave Howells and Willy
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Merge tag '6.3-rc-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6

Pull cifs client updates from Steve French:
 "The largest subset of this is from David Howells et al: making the
  cifs/smb3 driver pass iov_iters down to the lowest layers, directly to
  the network transport rather than passing lists of pages around,
  helping multiple areas:

   - Pin user pages, thereby fixing the race between concurrent DIO read
     and fork, where the pages containing the DIO read buffer may end up
     belonging to the child process and not the parent - with the result
     that the parent might not see the retrieved data.

   - cifs shouldn't take refs on pages extracted from non-user-backed
     iterators (eg. KVEC). With these changes, cifs will apply the
     appropriate cleanup.

   - Making it easier to transition to using folios in cifs rather than
     pages by dealing with them through BVEC and XARRAY iterators.

   - Allowing cifs to use the new splice function

  The remainder are:

   - fixes for stable, including various fixes for uninitialized memory,
     wrong length field causing mount issue to very old servers,
     important directory lease fixes and reconnect fixes

   - cleanups (unused code removal, change one element array usage, and
     a change form strtobool to kstrtobool, and Kconfig cleanups)

   - SMBDIRECT (RDMA) fixes including iov_iter integration and UAF fixes

   - reconnect fixes

   - multichannel fixes, including improving channel allocation (to
     least used channel)

   - remove the last use of lock_page_killable by moving to
     folio_lock_killable"

* tag '6.3-rc-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6: (46 commits)
  update internal module version number for cifs.ko
  cifs: update ip_addr for ses only for primary chan setup
  cifs: use tcon allocation functions even for dummy tcon
  cifs: use the least loaded channel for sending requests
  cifs: DIO to/from KVEC-type iterators should now work
  cifs: Remove unused code
  cifs: Build the RDMA SGE list directly from an iterator
  cifs: Change the I/O paths to use an iterator rather than a page list
  cifs: Add a function to read into an iter from a socket
  cifs: Add some helper functions
  cifs: Add a function to Hash the contents of an iterator
  cifs: Add a function to build an RDMA SGE list from an iterator
  netfs: Add a function to extract an iterator into a scatterlist
  netfs: Add a function to extract a UBUF or IOVEC into a BVEC iterator
  cifs: Implement splice_read to pass down ITER_BVEC not ITER_PIPE
  splice: Export filemap/direct_splice_read()
  iov_iter: Add a function to extract a page list from an iterator
  iov_iter: Define flags to qualify page extraction.
  splice: Add a func to do a splice from an O_DIRECT file without ITER_PIPE
  splice: Add a func to do a splice from a buffered file without ITER_PIPE
  ...
2023-02-22 17:12:44 -08:00
David Howells
7d58fe7310 iov_iter: Add a function to extract a page list from an iterator
Add a function, iov_iter_extract_pages(), to extract a list of pages from
an iterator.  The pages may be returned with a pin added or nothing,
depending on the type of iterator.

Add a second function, iov_iter_extract_will_pin(), to determine how the
cleanup should be done.

There are two cases:

 (1) ITER_IOVEC or ITER_UBUF iterator.

     Extracted pages will have pins (FOLL_PIN) obtained on them so that a
     concurrent fork() will forcibly copy the page so that DMA is done
     to/from the parent's buffer and is unavailable to/unaffected by the
     child process.

     iov_iter_extract_will_pin() will return true for this case.  The
     caller should use something like unpin_user_page() to dispose of the
     page.

 (2) Any other sort of iterator.

     No refs or pins are obtained on the page, the assumption is made that
     the caller will manage page retention.

     iov_iter_extract_will_pin() will return false.  The pages don't need
     additional disposal.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
cc: Al Viro <viro@zeniv.linux.org.uk>
cc: John Hubbard <jhubbard@nvidia.com>
cc: David Hildenbrand <david@redhat.com>
cc: Matthew Wilcox <willy@infradead.org>
cc: linux-fsdevel@vger.kernel.org
cc: linux-mm@kvack.org
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-02-20 17:25:43 -06:00
David Howells
f62e52d127 iov_iter: Define flags to qualify page extraction.
Define flags to qualify page extraction to pass into iov_iter_*_pages*()
rather than passing in FOLL_* flags.

For now only a flag to allow peer-to-peer DMA is supported.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
cc: Al Viro <viro@zeniv.linux.org.uk>
cc: Logan Gunthorpe <logang@deltatee.com>
cc: linux-fsdevel@vger.kernel.org
cc: linux-block@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-02-20 17:25:43 -06:00
David Howells
07073eb01c splice: Add a func to do a splice from a buffered file without ITER_PIPE
Provide a function to do splice read from a buffered file, pulling the
folios out of the pagecache directly by calling filemap_get_pages() to do
any required reading and then pasting the returned folios into the pipe.

A helper function is provided to do the actual folio pasting and will
handle multipage folios by splicing as many of the relevant subpages as
will fit into the pipe.

The code is loosely based on filemap_read() and might belong in
mm/filemap.c with that as it needs to use filemap_get_pages().

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
cc: Christoph Hellwig <hch@lst.de>
cc: Al Viro <viro@zeniv.linux.org.uk>
cc: David Hildenbrand <david@redhat.com>
cc: John Hubbard <jhubbard@nvidia.com>
cc: linux-mm@kvack.org
cc: linux-block@vger.kernel.org
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-02-20 17:25:43 -06:00
Keith Busch
4397a17c1d iov_iter: move iter_ubuf check inside restore WARN
io_uring is using iter_ubuf types for single vector requests. We expect
state restore may happen for this type now, and it is already handled
correctly, so suppress the warning.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2023-01-08 20:59:17 -07:00
Jens Axboe
2ad9bd8332 iov: add import_ubuf()
Like import_single_range(), but for ITER_UBUF.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2023-01-08 20:59:17 -07:00
Linus Torvalds
ce8a79d560 for-6.2/block-2022-12-08
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Merge tag 'for-6.2/block-2022-12-08' of git://git.kernel.dk/linux

Pull block updates from Jens Axboe:

 - NVMe pull requests via Christoph:
      - Support some passthrough commands without CAP_SYS_ADMIN (Kanchan
        Joshi)
      - Refactor PCIe probing and reset (Christoph Hellwig)
      - Various fabrics authentication fixes and improvements (Sagi
        Grimberg)
      - Avoid fallback to sequential scan due to transient issues (Uday
        Shankar)
      - Implement support for the DEAC bit in Write Zeroes (Christoph
        Hellwig)
      - Allow overriding the IEEE OUI and firmware revision in configfs
        for nvmet (Aleksandr Miloserdov)
      - Force reconnect when number of queue changes in nvmet (Daniel
        Wagner)
      - Minor fixes and improvements (Uros Bizjak, Joel Granados, Sagi
        Grimberg, Christoph Hellwig, Christophe JAILLET)
      - Fix and cleanup nvme-fc req allocation (Chaitanya Kulkarni)
      - Use the common tagset helpers in nvme-pci driver (Christoph
        Hellwig)
      - Cleanup the nvme-pci removal path (Christoph Hellwig)
      - Use kstrtobool() instead of strtobool (Christophe JAILLET)
      - Allow unprivileged passthrough of Identify Controller (Joel
        Granados)
      - Support io stats on the mpath device (Sagi Grimberg)
      - Minor nvmet cleanup (Sagi Grimberg)

 - MD pull requests via Song:
      - Code cleanups (Christoph)
      - Various fixes

 - Floppy pull request from Denis:
      - Fix a memory leak in the init error path (Yuan)

 - Series fixing some batch wakeup issues with sbitmap (Gabriel)

 - Removal of the pktcdvd driver that was deprecated more than 5 years
   ago, and subsequent removal of the devnode callback in struct
   block_device_operations as no users are now left (Greg)

 - Fix for partition read on an exclusively opened bdev (Jan)

 - Series of elevator API cleanups (Jinlong, Christoph)

 - Series of fixes and cleanups for blk-iocost (Kemeng)

 - Series of fixes and cleanups for blk-throttle (Kemeng)

 - Series adding concurrent support for sync queues in BFQ (Yu)

 - Series bringing drbd a bit closer to the out-of-tree maintained
   version (Christian, Joel, Lars, Philipp)

 - Misc drbd fixes (Wang)

 - blk-wbt fixes and tweaks for enable/disable (Yu)

 - Fixes for mq-deadline for zoned devices (Damien)

 - Add support for read-only and offline zones for null_blk
   (Shin'ichiro)

 - Series fixing the delayed holder tracking, as used by DM (Yu,
   Christoph)

 - Series enabling bio alloc caching for IRQ based IO (Pavel)

 - Series enabling userspace peer-to-peer DMA (Logan)

 - BFQ waker fixes (Khazhismel)

 - Series fixing elevator refcount issues (Christoph, Jinlong)

 - Series cleaning up references around queue destruction (Christoph)

 - Series doing quiesce by tagset, enabling cleanups in drivers
   (Christoph, Chao)

 - Series untangling the queue kobject and queue references (Christoph)

 - Misc fixes and cleanups (Bart, David, Dawei, Jinlong, Kemeng, Ye,
   Yang, Waiman, Shin'ichiro, Randy, Pankaj, Christoph)

* tag 'for-6.2/block-2022-12-08' of git://git.kernel.dk/linux: (247 commits)
  blktrace: Fix output non-blktrace event when blk_classic option enabled
  block: sed-opal: Don't include <linux/kernel.h>
  sed-opal: allow using IOC_OPAL_SAVE for locking too
  blk-cgroup: Fix typo in comment
  block: remove bio_set_op_attrs
  nvmet: don't open-code NVME_NS_ATTR_RO enumeration
  nvme-pci: use the tagset alloc/free helpers
  nvme: add the Apple shared tag workaround to nvme_alloc_io_tag_set
  nvme: only set reserved_tags in nvme_alloc_io_tag_set for fabrics controllers
  nvme: consolidate setting the tagset flags
  nvme: pass nr_maps explicitly to nvme_alloc_io_tag_set
  block: bio_copy_data_iter
  nvme-pci: split out a nvme_pci_ctrl_is_dead helper
  nvme-pci: return early on ctrl state mismatch in nvme_reset_work
  nvme-pci: rename nvme_disable_io_queues
  nvme-pci: cleanup nvme_suspend_queue
  nvme-pci: remove nvme_pci_disable
  nvme-pci: remove nvme_disable_admin_queue
  nvme: merge nvme_shutdown_ctrl into nvme_disable_ctrl
  nvme: use nvme_wait_ready in nvme_shutdown_ctrl
  ...
2022-12-13 10:43:59 -08:00
Al Viro
a41dad905e iov_iter: saner checks for attempt to copy to/from iterator
instead of "don't do it to ITER_PIPE" check for ->data_source being
false on copying from iterator.  Check for !->data_source for
copying to iterator, while we are at it.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2022-11-25 13:01:21 -05:00
Al Viro
c67f1fd2b2 csum_and_copy_to_iter(): handle ITER_DISCARD
Not hard to implement - we are not copying anything here, so
csum_and_memcpy() is not usable, but calculating a checksum
of source directly is trivial...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2022-11-25 13:01:20 -05:00
Al Viro
40a86061a5 get rid of unlikely() on page_copy_sane() calls
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2022-11-25 13:01:20 -05:00
Logan Gunthorpe
d82076403c iov_iter: introduce iov_iter_get_pages_[alloc_]flags()
Add iov_iter_get_pages_flags() and iov_iter_get_pages_alloc_flags()
which take a flags argument that is passed to get_user_pages_fast().

This is so that FOLL_PCI_P2PDMA can be passed when appropriate.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221021174116.7200-4-logang@deltatee.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-11-09 11:29:20 -07:00
Alexander Potapenko
33b75c1d88 instrumented.h: allow instrumenting both sides of copy_from_user()
Introduce instrument_copy_from_user_before() and
instrument_copy_from_user_after() hooks to be invoked before and after the
call to copy_from_user().

KASAN and KCSAN will be only using instrument_copy_from_user_before(), but
for KMSAN we'll need to insert code after copy_from_user().

Link: https://lkml.kernel.org/r/20220915150417.722975-4-glider@google.com
Signed-off-by: Alexander Potapenko <glider@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Eric Biggers <ebiggers@google.com>
Cc: Eric Biggers <ebiggers@kernel.org>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Ilya Leoshkevich <iii@linux.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vegard Nossum <vegard.nossum@oracle.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-03 14:03:18 -07:00
Al Viro
c03f05f183 fix copy_page_from_iter() for compound destinations
had been broken for ITER_BVEC et.al. since ever (OK, v3.17 when
ITER_BVEC had first appeared)...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2022-08-08 22:37:26 -04:00
Al Viro
f0f6b614f8 copy_page_to_iter(): don't split high-order page in case of ITER_PIPE
... just shove it into one pipe_buffer.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2022-08-08 22:37:25 -04:00
Al Viro
310d9d5a50 expand those iov_iter_advance()...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2022-08-08 22:37:25 -04:00
Al Viro
746de1f86f pipe_get_pages(): switch to append_pipe()
now that we are advancing the iterator, there's no need to
treat the first page separately - just call append_pipe()
in a loop.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2022-08-08 22:37:25 -04:00
Al Viro
eba2d3d798 get rid of non-advancing variants
mechanical change; will be further massaged in subsequent commits

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2022-08-08 22:37:24 -04:00
Al Viro
3cf42da327 iov_iter: saner helper for page array allocation
All call sites of get_pages_array() are essenitally identical now.
Replace with common helper...

Returns number of slots available in resulting array or 0 on OOM;
it's up to the caller to make sure it doesn't ask to zero-entry
array (i.e. neither maxpages nor size are allowed to be zero).

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2022-08-08 22:37:22 -04:00