This patch adds support of preadv2 and pwritev2 which are similar to
preadv/pwritev but with an extra flag argument. As for preadv/pwritev
both interfaces are added a non-standard GNU API.
For default 'posix' implementation trying to emulate the Linux supported
flags is troublesome:
* We can not temporary change the file state of the O_DSYNC and O_SYNC
flags to emulate RWF_{D}SYNC (attempts to change the state of using
fcntl are silently ignored).
* IOCB_HIPRI requires the file opened in O_DIRECT and uses an internal
semantic not provided by any other flag (O_NONBLOCK for instance).
So default sysdeps/posix implementations fails with EOPNOTSUPP for any non
supported flag (which are none currently) calls generic preadv/pwritev.
Basically this implementation supports only preadv2 called as preadv (with
flags sets to 0).
The Linux one uses the preadv2/pwritev2 syscall if defined, otherwise it
call preadv/writev. Instead of using the previous __ASSUME_* to
unconditionally issue the syscall (and avoid building the fallback routine),
it call pread/write if the preadv2/pwritev2 syscalls fails. The idea
is just avoid adding another __ASSUME_* and checking each architecture
on every kernel bump and simplify code conditionals.
Checked on x86_64-linux-gnu and on i686-linux-gnu and a check with
run-built-tests=no on aarch64-linux-gnu, alpha-linux-gnu, arm-linux-gnueabihf,
ia64-linux-gnu, m68k-linux-gnu, microblaze-linux-gnu, mips{64,64n32}-linux-gnu,
nios2-linux-gnu, powerpc{64,64le}-linux-gnu, s390{x}-linux-gnu,
sparc{64,v9}-linux-gnu, tile{gx,pro}-linux-gnu, and sh4-linux-gnu (all using
gcc 6.3).
* NEWS: Add note about pwritev2 and preadv2 inclusion.
* misc/Makefile (routines): Add preadv2, preadv64v2, pwritev2, and
pwritev64v2.
(tests): Add tst-preadvwritev2 and tst-preadvwritev64v2.
* misc/Versions (GLIBC_2.26): Add preadv2, preadv64v2, pwritev2, and
pwritev64v2.
* misc/preadv2.c: New file.
* misc/preadv64v2.c: Likewise.
* misc/pwritev2.c: Likewise.
* misc/pwritev64v2.c: Likewise.
* misc/tst-preadvwritev2.c: Likewise.
* misc/tst-preadvwritev64v2.c: Likewise.
* manual/llio.texi: Add preadv2 and pwritev2 documentation.
* misc/sys/uio.h [__USE_GNU && !__USE_FILE_OFFSET64] (preadv2): New
prototype.
[__USE_GNU && !__USE_FILE_OFFSET64] (pwritev2): Likewise.
[__USE_GNU && __USE_FILE_OFFSET64] (preadv64v2): Likewise.
[__USE_GNU && __USE_FILE_OFFSET64] (pwritev64v2): Likewise.
* misc/tst-preadvwritev-common.c (PREADV): Define if not defined.
(PWRITEV): Likewise.
(do_test_with_offset): Use PREADV and PWRITEV macros and check for
ENOSYS.
* nptl/tst-cancel4.c (tf_pwritev2): New test.
(tf_preadv2): Likewise.
(tf_fsync): Add tf_pwritev2 and tf_preadv2.
* sysdeps/posix/preadv2.c: Likewise.
* sysdeps/posix/preadv64v2.c: Likewise.
* sysdeps/posix/pwritev2.c: Likewise.
* sysdeps/posix/pwritev64v2.c: Likewise.
* sysdeps/unix/sysv/linux/kernel-features.h: Add comment for syscall
support in kernel.
* sysdeps/unix/sysv/linux/preadv2.c: Likewise.
* sysdeps/unix/sysv/linux/preadv64v2.c: Likewise.
* sysdeps/unix/sysv/linux/pwritev2.c: Likewise.
* sysdeps/unix/sysv/linux/pwritev64v2.c: Likewise.
* sysdeps/unix/sysv/linux/preadv.c (preadv): Add libc_hidden_def.
* sysdeps/unix/sysv/linux/preadv64.c (preadv64): Likewise.
* sysdeps/unix/sysv/linux/pwritev.c (pwritev): Likewise.
* sysdeps/unix/sysv/linux/pwritev64.c (pwritev64): Likewise.
* sysdeps/unix/sysv/linux/bits/uio.h: Add supported preadv2/pwritev2
support flags on Linux.
* sysdeps/unix/sysv/linux/aarch64/libc.abilist (GLIBC_2.26): Add
preadv2, preadv64v2, pwritev2, pwritev64v2.
* sysdeps/unix/sysv/linux/alpha/libc.abilist (GLIBC_2.26): Likewise.
* sysdeps/unix/sysv/linux/arm/libc.abilist (GLIBC_2.26): Likewise.
* sysdeps/unix/sysv/linux/hppa/libc.abilist (GLIBC_2.26): Likewise.
* sysdeps/unix/sysv/linux/i386/libc.abilist (GLIBC_2.26): Likewise.
* sysdeps/unix/sysv/linux/ia64/libc.abilist (GLIBC_2.26): Likewise.
* sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist (GLIBC_2.26):
Likewise.
* sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist (GLIBC_2.26):
Likewise.
* sysdeps/unix/sysv/linux/microblaze/libc.abilist (GLIBC_2.26):
Likewise.
* sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist (GLIBC_2.26):
Likewise.
* sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist (GLIBC_2.26):
Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist (GLIBC_2.26):
Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist (GLIBC_2.26):
Likewise.
* sysdeps/unix/sysv/linux/nios2/libc.abilist (GLIBC_2.26): Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist
(GLIBC_2.26): Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist
(GLIBC_2.26): Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/libc.abilist (GLIBC_2.26):
Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/libc-le.abilist
(GLIBC_2.26): Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist (GLIBC_2.26):
Likewise.
* sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist (GLIBC_2.26):
Likewise.
* sysdeps/unix/sysv/linux/sh/libc.abilist (GLIBC_2.26): Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist (GLIBC_2.26):
Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist (GLIBC_2.26):
Likewise.
* sysdeps/sysv/linux/tile/tilegx/tilegx32/libc.abilist (GLIBC_2.26):
Likewise.
* sysdeps/sysv/linux/tile/tilegx/tilegx64/libc.abilist (GLIBC_2.26):
Likewise.
* sysdeps/unix/sysv/linux/tile/tilepro/libc.abilist (GLIBC_2.26):
Likewise.
* sysdeps/unix/sysv/linux/x86_64/64/libc.abilist (GLIBC_2.26):
Likewise.
* sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist (GLIBC_2.26):
Likewise.
Currently all architectures but microblaze use wire-up syscall for
p{readv,write}v. Microblaze still uses the syscall emulation using
sysdep/posix/p{readv,writev}.c and it was reported in some ocasions
[1] [2] that it might have some issues with some linux specific
usage (mainly with O_DIRECT and the alignment requirement).
Although it is not an issue for virtually all the system, this
patch refactors the sysdeps/posix p{read,write}v syscall to avoid
such issue (by using posix_memalign on the buffer used on
p{read,write} call) and by refactoring it common files to avoid
the need check on defines to correct set the alias and internal
symbols.
Checked on microblaze-linux-gnu check with run-built-tests=no and
by using the sysdeps/posix implementation on x86_64-linux-gnu (just
for sanity test where it shown no regression).
* sysdeps/posix/preadv.c: Use sysdeps/posix/preadv_common.c.
* sysdeps/posix/preadv64.c: Likewise.
* sysdeps/unix/sysv/linux/preadv.c: Likewise.
* sysdeps/unix/sysv/linux/preadv64.c: Likewise.
* sysdeps/posix/pwritev.c: Use sysdeps/posix/pwritev_common.c.
* sysdeps/posix/pwritev64.c: Likewise.
* sysdeps/unix/sysv/linux/pwritev.c: Likewise.
* sysdeps/unix/sysv/linux/pwritev64.c: Likewise.
* sysdeps/posix/preadv_common.c: New file.
* sysdeps/posix/pwritev_common.c: Likewise.
[1] http://www.mail-archive.com/qemu-devel@nongnu.org/msg25282.html
[2] https://bugzilla.redhat.com/show_bug.cgi?id=563103#c8
This patch removes the __ASSUME_OFF_DIFF_OFF64 define introduced in
p{read,write} consolidation patch. This define was added based on
the idea 32 bits ports would continue to follow previous off{64}_t
definition where off_t size differs from off64_t one.
However, with recent AArch64/ILP32 patch submission and also with
discussion for RISCV kernel interface, 32 bits ports now may aim
to use off_t and off64_t with the same size as 64 bits.
So current assumption for both p{read,write} and p{read,write}v
are not compatible with new type definition. This patch now makes
the syscall wrappers to only depend on __OFF_T_MATCHES_OFF64_T to
define the default and 64-suffix variant, as follow:
<function>.c
#ifndef __OFF_T_MATCHES_OFF64_T
/* build <function> */
#endif
and
<function>64.c
/* build <function>64 */
#ifdef __OFF_T_MATCHES_OFF64_T
weak_alias (fallocate64, fallocate)
#endif
Tested on x86_64, i686, x32, and armhf.
* sysdeps/unix/sysv/linux/mips/kernel-features.h
(__ASSUME_OFF_DIFF_OFF64): Remove define.
* sysdeps/unix/sysv/linux/pread.c
[__WORDSIZE != 64 || __ASSUME_OFF_DIFF_OFF64] (pread): Replace by
__OFF_T_MATCHES_OFF64_T.
* sysdeps/unix/sysv/linux/pread64.c
[__WORDSIZE != 64 || __ASSUME_OFF_DIFF_OFF64] (pread64): Likewise.
* sysdeps/unix/sysv/linux/preadv.c
[__WORDSIZE != 64 || __ASSUME_OFF_DIFF_OFF64] (preadv): Likewise.
* sysdeps/unix/sysv/linux/preadv64.c
[__WORDSIZE != 64 || __ASSUME_OFF_DIFF_OFF64] (preadv64): Likewise.
* sysdeps/unix/sysv/linux/pwrite.c
[__WORDSIZE != 64 || __ASSUME_OFF_DIFF_OFF64] (pwrite): Likewise.
* sysdeps/unix/sysv/linux/pwrite64.c
[__WORDSIZE != 64 || __ASSUME_OFF_DIFF_OFF64] (pwrite64): Likewise.
* sysdeps/unix/sysv/linux/pwritev.c
[__WORDSIZE != 64 || __ASSUME_OFF_DIFF_OFF64] (pwritev): Likewise.
* sysdeps/unix/sysv/linux/pwritev64.c
[__WORDSIZE != 64 || __ASSUME_OFF_DIFF_OFF64] (pwritev64): Likewise.
This patch fixes the p{readv,writev}{64} consolidation implementation
from commits 4e77815 and af5fdf5. Different from pread/pwrite
implementation, preadv/pwritev implementation does not require
__ALIGNMENT_ARG because kernel syscall prototypes define
the high and low part of the off_t, if it is the case, directly
(different from pread/pwrite where the architecture ABI for passing
64-bit values must be in consideration for passsing the arguments).
It also adds some basic tests for preadv/pwritev.
Tested on x86_64, i686, and armhf.
* misc/Makefile (tests): Add tst-preadvwritev and tst-preadvwritev64.
* misc/tst-preadvwritev.c: New file.
* misc/tst-preadvwritev64.c: Likewise.
* sysdeps/unix/sysv/linux/preadv.c (preadv): Remove SYSCALL_LL{64}
usage.
* sysdeps/unix/sysv/linux/preadv64.c (preadv64): Likewise.
* sysdeps/unix/sysv/linux/pwritev.c (pwritev): Likewise.
* sysdeps/unix/sysv/linux/pwritev64.c (pwritev64): Likewise.
* sysdeps/unix/sysv/linux/sysdep.h (LO_HI_LONG): New macro.
This patch consolidates all the preadv{64} implementation for Linux
in only one (sysdeps/unix/sysv/linux/preadv{64}.c). It also removes the
syscall from the auto-generation using assembly macros.
It was based on previous pread/pread64 consolidation patch. The new macro
SYSCALL_LL{64} is used to handle the offset argument and alias is created
for __ASSUME_OFF_DIFF_OFF64 in case of pread64.
Checked on x86_64, i386, aarch64, and powerpc64le.
* misc/Makefile (CFLAGS-preadv.c): New variable: add cancellation
required flags.
(CFLAGS-preadv64.c): Likewise.
* sysdeps/unix/sysv/linux/generic/wordsize-32/preadv.c: Remove file.
* sysdeps/unix/sysv/linux/generic/wordsize-32/preadv64.c: Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/n64/preadv64.c: Likewise.
* sysdeps/unix/sysv/linux/wordsize-64/preadv.c: Likewise.
* sysdeps/unix/sysv/linux/wordsize-64/preadv64.: Likwise.
* sysdeps/unix/sysv/linux/x86_64/x32/syscalls.list (preadv): Remove
syscall from auto-generation.
* sysdeps/unix/sysv/linux/preadv.c: Rewrite implementation.
[WORDSIZE == 64] (preadv64): Remove macro.
[!PREADV] (PREADV): Likewise.
[!PREADV] (PREADV_REPLACEMENT): Likewise.
[!PREADV] (PREAD): Likewise.
[!PREADV] (OFF_T): Likewise.
[!__ASSUME_PREADV] (PREADV_REPLACEMENT): Likewise.
(LO_HI_LONG): Remove macro.
[__WORDSIZE != 64 || __ASSUME_OFF_DIFF_OFF64] (preadv): Add function.
* sysdeps/unix/sysv/linux/preadv64.c: Rewrite implementation.
(PREADV): Remove macro.
(PREADV_REPLACEMENTE): Likewise.
(PREAD): Likewise.
(OFF_T): Likewise.
(preadv64): New function.
* nptl/tst-cancel4.c (tf_preadv): Add test.
* misc/Versions: Export preadv, preadv64, pwritev, pwritev64 for
GLIBC_2.10.
* misc/sys/uio.h: Declare preadv, preadv64, pwritev, pwritev64.
* sysdeps/unix/sysv/linux/kernel-features.h: Add entries for preadv
and pwritev.
* misc/preadv.c: New file.
* misc/preadv64.c: New file.
* misc/pwritev.c: New file.
* misc/pwritev64.c: New file.
* sysdeps/posx/preadv.c: New file.
* sysdeps/posx/preadv64.c: New file.
* sysdeps/posx/pwritev.c: New file.
* sysdeps/posx/pwritev64.c: New file.
* sysdeps/unix/sysv/linux/preadv.c: New file.
* sysdeps/unix/sysv/linux/preadv64.c: New file.
* sysdeps/unix/sysv/linux/pwritev.c: New file.
* sysdeps/unix/sysv/linux/pwritev64.c: New file.
* sysdeps/unix/sysv/linux/wordsize-64/preadv64.c: New file.
* sysdeps/unix/sysv/linux/wordsize-64/pwritev64.c: New file.
Joseph Myers
Florian Weimer
Adhemerval Zanella
Ulrich Drepper