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This patch consolidates all Linux mmap implementations on default
sysdeps/unix/sysv/linux/mmap{64}.c one. To accomodate all required
architecture specific requeriments a new internal header is created
(mmap_internal.h) where each architecture add its specific code
requirements. Currently only x86_64 (to define MMAP_PREPARE to add
MAP_32BITS), s390 (which have a different kernel ABI for mmap), m68k
(which have variable minimum page sizes), and MIPS n32 (which zero
extend the offset to handle negative one correctly) redefine the new
header.
The patch also fixes BZ#21270 where default mmap64 on architectures
which uses mmap2 silent truncates large offsets value (larger than
1 << (page shift + 8 * sizeof (off_t)) or 1<<44 on architectures with
4096 bytes page size). The new consolidate implementation returns
EINVAL as allowed by POSIX.
It also adds a tests for on current tst-mmap-offset one. I have run
a full make check on x86_64, x86_64-32, i686, aarch64, armhf, powerpc,
powerpc64le, sparc64, and sparcv9 without any regressions. I also ran
some basic tests (tst-mmap-offset) on sh4, m68k, and on qemu simulated
MIPS32 and MIPS64.
[BZ #21270]
* posix/tst-mmap-offset.c (do_prepare): New function.
(do_test): Rename to do_test_bz18877 and use FAIL_RET.
(do_test_bz21270): New function.
* sysdeps/unix/sysv/linux/aarch64/mmap.c: Remove file.
* sysdeps/unix/sysv/linux/arm/mmap.c: Remove file.
* sysdeps/unix/sysv/linux/generic/wordsize-32/mmap.c: Likewise.
* sysdeps/unix/sysv/linux/hppa/mmap.c: Likewise.
* sysdeps/unix/sysv/linux/i386/mmap.c: Likewise.
* sysdeps/unix/sysv/linux/m68k/mmap.S: Likewise.
* sysdeps/unix/sysv/linux/m68k/mmap64.c: Likewise.
* sysdeps/unix/sysv/linux/microblaze/mmap.S: Likewise.
* sysdeps/unix/sysv/linux/mips/mips32/mmap.c: Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/n32/mmap.c: Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/n64/mmap64.c: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/mmap.S: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/mmap64.S: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-64/mmap.S: Likewise.
* sysdeps/unix/sysv/linux/wordsize-64/mmap.c: Likewise.
* sysdeps/unix/sysv/linux/wordsize-64/mmap64.c: Likewise.
* sysdeps/unix/sysv/linux/x86_64/64/mmap.c: Likewise.
* sysdeps/unix/sysv/linux/mmap_internal.h: New file.
* sysdeps/unix/sysv/linux/m68k/mmap_internal.h: Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/n32/mmap_internal.h: Likewise.
* sysdeps/unix/sysv/linux/s390/mmap_internal.h: Likewise.
* sysdeps/unix/sysv/linux/x86_64/64/mmap_internal.h: Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/n64/syscalls.list: Remove mmap
from auto-generation list.
* sysdeps/unix/sysv/linux/mips/mips64/n32/syscalls.list: Likewise.
* sysdeps/unix/sysv/linux/wordsize-64/syscalls.list: Likewise.
* sysdeps/unix/sysv/linux/mmap.c: New file.
* sysdeps/unix/sysv/linux/mmap64.c (__mmap64): Add check for invalid
offsets and support for mmap2 syscall.
This hierarchy supports Linux systems using the new asm-generic/unistd.h, which removes many familiar old syscalls. For example, to implement open(), newer Linux architectures require glibc to invoke the __NR_openat syscall with AT_FDCWD. This hierarchy provides all those implementations. It also provides support for 32-bit platforms using the 64-bit kernel syscall APIs, as the 32-bit ones are no longer provided. Note that newer ILP32 environments (x32 or AArch64:ILP32, for example) are converting to use more 64-bit types in kernel syscalls, so that aspect of this support is in more flux as of this writing.