aio: Comment use of IOCB_FLAG_IOPRIO aio flag

Comment the use of the IOCB_FLAG_IOPRIO aio flag similarly to the
IOCB_FLAG_RESFD flag.

Reviewed-by: Christoph Hellwig <[email protected]>
Reviewed-by: Johann

aio: Comment use of IOCB_FLAG_IOPRIO aio flag

Comment the use of the IOCB_FLAG_IOPRIO aio flag similarly to the
IOCB_FLAG_RESFD flag.

Reviewed-by: Christoph Hellwig <[email protected]>
Reviewed-by: Johannes Thumshirn <[email protected]>
Signed-off-by: Damien Le Moal <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>

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aio: implement IOCB_CMD_POLL

Simple one-shot poll through the io_submit() interface. To poll for
a file descriptor the application should submit an iocb of type
IOCB_CMD_POLL. It will poll the fd

aio: implement IOCB_CMD_POLL

Simple one-shot poll through the io_submit() interface. To poll for
a file descriptor the application should submit an iocb of type
IOCB_CMD_POLL. It will poll the fd for the events specified in the
the first 32 bits of the aio_buf field of the iocb.

Unlike poll or epoll without EPOLLONESHOT this interface always works
in one shot mode, that is once the iocb is completed, it will have to be
resubmitted.

Signed-off-by: Christoph Hellwig <[email protected]>
Tested-by: Avi Kivity <[email protected]>

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aio: don't expose __aio_sigset in uapi

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

aio: don't expose __aio_sigset in uapi

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 <[email protected]>
Reported-by: Adrian Reber <[email protected]>
Signed-off-by: Al Viro <[email protected]>

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aio: mark __aio_sigset::sigmask const

io_pgetevents() will not change the signal mask. Mark it const to make
it clear and to reduce the need for casts in user code.

Reviewed-by: Christoph Hellwig

aio: mark __aio_sigset::sigmask const

io_pgetevents() will not change the signal mask. Mark it const to make
it clear and to reduce the need for casts in user code.

Reviewed-by: Christoph Hellwig <[email protected]>
Signed-off-by: Avi Kivity <[email protected]>
Signed-off-by: Al Viro <[email protected]>
[hch: reapply the patch that got incorrectly reverted]
Signed-off-by: Christoph Hellwig <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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

The poll() changes were not well thought out, and completely
unexplained. They also caused a huge performance regression, because
"-

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

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 <[email protected]>
Cc: Christoph Hellwig <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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aio: mark __aio_sigset::sigmask const

io_pgetevents() will not change the signal mask. Mark it const
to make it clear and to reduce the need for casts in user code.

Reviewed-by: Christoph Hellwig <

aio: mark __aio_sigset::sigmask const

io_pgetevents() will not change the signal mask. Mark it const
to make it clear and to reduce the need for casts in user code.

Reviewed-by: Christoph Hellwig <[email protected]>
Signed-off-by: Avi Kivity <[email protected]>
Signed-off-by: Al Viro <[email protected]>

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fs: Add aio iopriority support

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 fi

fs: Add aio iopriority support

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 <[email protected]>
Reviewed-by: Jeff Moyer <[email protected]>
Reviewed-by: Christoph Hellwig <[email protected]>
Signed-off-by: Al Viro <[email protected]>

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aio: implement IOCB_CMD_POLL

Simple one-shot poll through the io_submit() interface. To poll for
a file descriptor the application should submit an iocb of type
IOCB_CMD_POLL. It will poll the fd

aio: implement IOCB_CMD_POLL

Simple one-shot poll through the io_submit() interface. To poll for
a file descriptor the application should submit an iocb of type
IOCB_CMD_POLL. It will poll the fd for the events specified in the
the first 32 bits of the aio_buf field of the iocb.

Unlike poll or epoll without EPOLLONESHOT this interface always works
in one shot mode, that is once the iocb is completed, it will have to be
resubmitted.

Signed-off-by: Christoph Hellwig <[email protected]>
Reviewed-by: Darrick J. Wong <[email protected]>

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aio: implement io_pgetevents

This is the io_getevents equivalent of ppoll/pselect and allows to
properly mix signals and aio completions (especially with IOCB_CMD_POLL)
and atomically executes the f

aio: implement io_pgetevents

This is the io_getevents equivalent of ppoll/pselect and allows to
properly mix signals and aio completions (especially with IOCB_CMD_POLL)
and atomically executes the following sequence:

sigset_t origmask;

pthread_sigmask(SIG_SETMASK, &sigmask, &origmask);
ret = io_getevents(ctx, min_nr, nr, events, timeout);
pthread_sigmask(SIG_SETMASK, &origmask, NULL);

Note that unlike many other signal related calls we do not pass a sigmask
size, as that would get us to 7 arguments, which aren't easily supported
by the syscall infrastructure. It seems a lot less painful to just add a
new syscall variant in the unlikely case we're going to increase the
sigset size.

Signed-off-by: Christoph Hellwig <[email protected]>
Reviewed-by: Greg Kroah-Hartman <[email protected]>
Reviewed-by: Darrick J. Wong <[email protected]>

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annotate RWF_... flags

[AV: added missing annotations in syscalls.h/compat.h]

Signed-off-by: Christoph Hellwig <[email protected]>
Signed-off-by: Al Viro <[email protected]>

fs: Use RWF_* flags for AIO operations

aio_rw_flags is introduced in struct iocb (using aio_reserved1) which will
carry the RWF_* flags. We cannot use aio_flags because they are not
checked for vali

fs: Use RWF_* flags for AIO operations

aio_rw_flags is introduced in struct iocb (using aio_reserved1) which will
carry the RWF_* flags. We cannot use aio_flags because they are not
checked for validity which may break existing applications.

Note, the only place RWF_HIPRI comes in effect is dio_await_one().
All the rest of the locations, aio code return -EIOCBQUEUED before the
checks for RWF_HIPRI.

Reviewed-by: Christoph Hellwig <[email protected]>
Reviewed-by: Jan Kara <[email protected]>
Signed-off-by: Goldwyn Rodrigues <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>

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UAPI: fix endianness conditionals in linux/aio_abi.h

In the UAPI header files, __BIG_ENDIAN and __LITTLE_ENDIAN must be
compared against __BYTE_ORDER in preprocessor conditionals where these are
exp

UAPI: fix endianness conditionals in linux/aio_abi.h

In the UAPI header files, __BIG_ENDIAN and __LITTLE_ENDIAN must be
compared against __BYTE_ORDER in preprocessor conditionals where these are
exposed to userspace (that is they're not inside __KERNEL__ conditionals).

However, in the main kernel the norm is to check for
"defined(__XXX_ENDIAN)" rather than comparing against __BYTE_ORDER and
this has incorrectly leaked into the userspace headers.

The definition of PADDED() in linux/aio_abi.h is wrong in this way. Note
that userspace will likely interpret this and thus the order of fields in
struct iocb incorrectly as the little-endian variant on big-endian
machines - depending on header inclusion order.

[!!!] NOTE [!!!] This patch may adversely change the userspace API. It might
be better to fix the ordering of aio_key and aio_reserved1 in struct iocb.

Signed-off-by: David Howells <[email protected]>
Acked-by: Benjamin LaHaise <[email protected]>
Acked-by: Jeff Moyer <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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UAPI: (Scripted) Disintegrate include/linux

Signed-off-by: David Howells <[email protected]>
Acked-by: Arnd Bergmann <[email protected]>
Acked-by: Thomas Gleixner <[email protected]>
Acked-by: Michae

UAPI: (Scripted) Disintegrate include/linux

Signed-off-by: David Howells <[email protected]>
Acked-by: Arnd Bergmann <[email protected]>
Acked-by: Thomas Gleixner <[email protected]>
Acked-by: Michael Kerrisk <[email protected]>
Acked-by: Paul E. McKenney <[email protected]>
Acked-by: Dave Jones <[email protected]>

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