linux.git/fs/aio.c, branch v4.18

Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2018-07-22T19:04:51+00:00

Pull vfs fixes from Al Viro:
 "Fix several places that screw up cleanups after failures halfway
  through opening a file (one open-coding filp_clone_open() and getting
  it wrong, two misusing alloc_file()). That part is -stable fodder from
  the 'work.open' branch.

  And Christoph's regression fix for uapi breakage in aio series;
  include/uapi/linux/aio_abi.h shouldn't be pulling in the kernel
  definition of sigset_t, the reason for doing so in the first place had
  been bogus - there's no need to expose struct __aio_sigset in
  aio_abi.h at all"

* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  aio: don't expose __aio_sigset in uapi
  ocxlflash_getfile(): fix double-iput() on alloc_file() failures
  cxl_getfile(): fix double-iput() on alloc_file() failures
  drm_mode_create_lease_ioctl(): fix open-coded filp_clone_open()

aio: don't expose __aio_sigset in uapi

2018-07-18T03:26:58+00:00

glibc uses a different defintion of sigset_t than the kernel does,
and the current version would pull in both.  To fix this just do not
expose the type at all - this somewhat mirrors pselect() where we
do not even have a type for the magic sigmask argument, but just
use pointer arithmetics.

Fixes: 7a074e96 ("aio: implement io_pgetevents")
Signed-off-by: Christoph Hellwig 
Reported-by: Adrian Reber 
Signed-off-by: Al Viro

Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL

2018-06-28T17:40:47+00:00

The poll() changes were not well thought out, and completely
unexplained.  They also caused a huge performance regression, because
"->poll()" was no longer a trivial file operation that just called down
to the underlying file operations, but instead did at least two indirect
calls.

Indirect calls are sadly slow now with the Spectre mitigation, but the
performance problem could at least be largely mitigated by changing the
"->get_poll_head()" operation to just have a per-file-descriptor pointer
to the poll head instead.  That gets rid of one of the new indirections.

But that doesn't fix the new complexity that is completely unwarranted
for the regular case.  The (undocumented) reason for the poll() changes
was some alleged AIO poll race fixing, but we don't make the common case
slower and more complex for some uncommon special case, so this all
really needs way more explanations and most likely a fundamental
redesign.

[ This revert is a revert of about 30 different commits, not reverted
  individually because that would just be unnecessarily messy  - Linus ]

Cc: Al Viro 
Cc: Christoph Hellwig 
Signed-off-by: Linus Torvalds

aio: only return events requested in poll_mask() for IOCB_CMD_POLL

2018-06-15T00:08:14+00:00

The ->poll_mask() operation has a mask of events that the caller
is interested in, but not all implementations might take it into
account.  Mask the return value to only the requested events,
similar to what the poll and epoll code does.

Reported-by: Avi Kivity 
Signed-off-by: Christoph Hellwig 
Signed-off-by: Al Viro

fs: aio ioprio use ioprio_check_cap ret val

2018-06-04T18:20:39+00:00

Previously the value was ignored.

Signed-off-by: Adam Manzanares 
Signed-off-by: Al Viro

fs: Add aio iopriority support

2018-05-31T14:50:55+00:00

This is the per-I/O equivalent of the ioprio_set system call.

When IOCB_FLAG_IOPRIO is set on the iocb aio_flags field, then we set the
newly added kiocb ki_ioprio field to the value in the iocb aio_reqprio field.

This patch depends on block: add ioprio_check_cap function.

Signed-off-by: Adam Manzanares 
Reviewed-by: Jeff Moyer 
Reviewed-by: Christoph Hellwig 
Signed-off-by: Al Viro

fs: Convert kiocb rw_hint from enum to u16

2018-05-31T14:50:54+00:00

In order to avoid kiocb bloat for per command iopriority support, rw_hint
is converted from enum to a u16. Added a guard around ki_hint assignment.

Signed-off-by: Adam Manzanares 
Signed-off-by: Al Viro

aio: sanitize the limit checking in io_submit(2)

2018-05-30T03:20:17+00:00

as it is, the logics in native io_submit(2) is "if asked for
more than LONG_MAX/sizeof(pointer) iocbs to submit, don't
bother with more than LONG_MAX/sizeof(pointer)" (i.e.
512M requests on 32bit and 1E requests on 64bit) while
compat io_submit(2) goes with "stop after the first
PAGE_SIZE/sizeof(pointer) iocbs", i.e. 1K or so.  Which is
	* inconsistent
	* *way* too much in native case
	* possibly too little in compat one
and
	* wrong anyway, since the natural point where we
ought to stop bothering is ctx->nr_events

Reviewed-by: Christoph Hellwig 
Signed-off-by: Al Viro

aio: fold do_io_submit() into callers

2018-05-30T03:19:29+00:00

get rid of insane "copy array of 32bit pointers into an array of
native ones" glue.

Reviewed-by: Christoph Hellwig 
Signed-off-by: Al Viro

aio: shift copyin of iocb into io_submit_one()

2018-05-30T03:18:31+00:00

Reviewed-by: Christoph Hellwig 
Signed-off-by: Al Viro