This patch fixes the OFD ("file private") locks for architectures that
support non-LFS flock definition (__USE_FILE_OFFSET64 not defined). The
issue in this case is both F_OFD_{GETLK,SETLK,SETLKW} and
F_{SET,GET}L{W}K64 expects a flock64 argument and when using old
F_OFD_* flags with a non LFS flock argument the kernel might interpret
the underlying data wrongly. Kernel idea originally was to avoid using
such flags in non-LFS syscall, but since GLIBC uses fcntl with LFS
semantic as default it is possible to provide the functionality and
avoid the bogus struct kernel passing by adjusting the struct manually
for the required flags.
The idea follows other LFS interfaces that provide two symbols:
1. A new LFS fcntl64 is added on default ABI with the usual macros to
select it for FILE_OFFSET_BITS=64.
2. The Linux non-LFS fcntl use a stack allocated struct flock64 for
F_OFD_{GETLK,SETLK,SETLKW} copy the results on the user provided
struct.
3. Keep a compat symbol with old broken semantic for architectures
that do not define __OFF_T_MATCHES_OFF64_T.
So for architectures which defines __USE_FILE_OFFSET64, fcntl64 will
aliased to fcntl and no adjustment would be required. So to actually
use F_OFD_* with LFS support the source must be built with LFS support
(_FILE_OFFSET_BITS=64).
Also F_OFD_SETLKW command is handled a cancellation point, as for
F_SETLKW{64}.
Checked on x86_64-linux-gnu and i686-linux-gnu.
[BZ #20251]
* NEWS: Mention fcntl64 addition.
* csu/check_fds.c: Replace __fcntl_nocancel by __fcntl64_nocancel.
* login/utmp_file.c: Likewise.
* sysdeps/posix/fdopendir.c: Likewise.
* sysdeps/posix/opendir.c: Likewise.
* sysdeps/unix/pt-fcntl.c: Likewise.
* include/fcntl.h (__libc_fcntl64, __fcntl64,
__fcntl64_nocancel_adjusted): New prototype.
(__fcntl_nocancel_adjusted): Remove prototype.
* io/Makefile (routines): Add fcntl64.
(CFLAGS-fcntl64.c): New rule.
* io/Versions [GLIBC_2.28] (fcntl64): New symbol.
[GLIBC_PRIVATE] (__libc_fcntl): Rename to __libc_fcntl64.
* io/fcntl.h (fcntl64): Add prototype and redirect if
__USE_FILE_OFFSET64 is defined.
* io/fcntl64.c: New file.
* manual/llio.text: Add a note for which commands fcntl acts a
cancellation point.
* nptl/Makefile (CFLAGS-fcntl64.c): New rule.
* sysdeps/mach/hurd/fcntl.c: Alias fcntl to fcntl64 symbols.
* sysdeps/mach/hurd/i386/libc.abilist [GLIBC_2.28] (fcntl, fcntl64):
New symbols.
* sysdeps/unix/sysv/linux/fcntl.c (__libc_fcntl): Fix F_GETLK64,
F_OFD_GETLK, F_SETLK64, F_SETLKW64, F_OFD_SETLK, and F_OFD_SETLKW for
non-LFS case.
* sysdeps/unix/sysv/linux/fcntl64.c: New file.
* sysdeps/unix/sysv/linux/fcntl_nocancel.c (__fcntl_nocancel): Rename
to __fcntl64_nocancel.
(__fcntl_nocancel_adjusted): Rename to __fcntl64_nocancel_adjusted.
* sysdeps/unix/sysv/linux/not-cancel.h (__fcntl_nocancel): Rename
to __fcntl64_nocancel.
* sysdeps/unix/sysv/linux/tst-ofdlocks.c: New file.
* sysdeps/unix/sysv/linux/tst-ofdlocks-compat.c: Likewise.
* sysdeps/unix/sysv/linux/Makefile (tests): Add tst-ofdlocks.
(tests-internal): Add tst-ofdlocks-compat.
* sysdeps/unix/sysv/linux/aarch64/libc.abilist [GLIBC_2.28]
(fcntl64): New symbol.
* sysdeps/unix/sysv/linux/alpha/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/ia64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/libc-le.abilist: Likewise.
* sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/x86_64/64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/arm/libc.abilist [GLIBC_2.28] (fcntl,
fcntl64): Likewise.
* sysdeps/unix/sysv/linux/hppa/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/i386/libc.abilis: Likewise.
* sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/microblaze/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/nios2/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist:
Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist:
Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/sh/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist: Likewise.
Neither the <dlfcn.h> entry points, nor lazy symbol resolution, nor
initial shared library load-up, are cancellation points, so ld.so
should exclusively use I/O primitives that are not cancellable. We
currently achieve this by having the cancellation hooks compile as
no-ops when IS_IN(rtld); this patch changes to using exclusively
_nocancel primitives in the source code instead, which makes the
intent clearer and significantly reduces the amount of code compiled
under IS_IN(rtld) as well as IS_IN(libc) -- in particular,
elf/Makefile no longer thinks we require a copy of unwind.c in
rtld-libc.a. (The older mechanism is preserved as a backstop.)
The bulk of the change is splitting up the files that define the
_nocancel I/O functions, so they don't also define the variants that
*are* cancellation points; after which, the existing logic for picking
out the bits of libc that need to be recompiled as part of ld.so Just
Works. I did this for all of the _nocancel functions, not just the
ones used by ld.so, for consistency.
fcntl was a little tricky because it's only a cancellation point for
certain opcodes (F_SETLKW(64), which can block), and the existing
__fcntl_nocancel wasn't applying the FCNTL_ADJUST_CMD hook, which
strikes me as asking for trouble, especially as the only nontrivial
definition of FCNTL_ADJUST_CMD (for powerpc64) changes F_*LK* opcodes.
To fix this, fcntl_common moves to fcntl_nocancel.c along with
__fcntl_nocancel, and changes its name to the extern (but hidden)
symbol __fcntl_nocancel_adjusted, so that regular fcntl can continue
calling it. __fcntl_nocancel now applies FCNTL_ADJUST_CMD; so that
both both fcntl.c and fcntl_nocancel.c can see it, the only nontrivial
definition moves from sysdeps/u/s/l/powerpc/powerpc64/fcntl.c to
.../powerpc64/sysdep.h and becomes entirely a macro, instead of a macro
that calls an inline function.
The nptl version of libpthread also changes a little, because its
"compat-routines" formerly included files that defined all the
_nocancel functions it uses; instead of continuing to duplicate them,
I exported the relevant ones from libc.so as GLIBC_PRIVATE. Since the
Linux fcntl.c calls a function defined by fcntl_nocancel.c, it can no
longer be used from libpthread.so; instead, introduce a custom
forwarder, pt-fcntl.c, and export __libc_fcntl from libc.so as
GLIBC_PRIVATE. The nios2-linux ABI doesn't include a copy of vfork()
in libpthread, and it was handling that by manipulating
libpthread-routines in .../linux/nios2/Makefile; it is cleaner to do
what other such ports do, and have a pt-vfork.S that defines no symbols.
Right now, it appears that Hurd does not implement _nocancel I/O, so
sysdeps/generic/not-cancel.h will forward everything back to the
regular functions. This changed the names of some of the functions
that sysdeps/mach/hurd/dl-sysdep.c needs to interpose.
* elf/dl-load.c, elf/dl-misc.c, elf/dl-profile.c, elf/rtld.c
* sysdeps/unix/sysv/linux/dl-sysdep.c
Include not-cancel.h. Use __close_nocancel instead of __close,
__open64_nocancel instead of __open, __read_nocancel instead of
__libc_read, and __write_nocancel instead of __libc_write.
* csu/check_fds.c (check_one_fd)
* sysdeps/posix/fdopendir.c (__fdopendir)
* sysdeps/posix/opendir.c (__alloc_dir): Use __fcntl_nocancel
instead of __fcntl and/or __libc_fcntl.
* sysdeps/unix/sysv/linux/pthread_setname.c (pthread_setname_np)
* sysdeps/unix/sysv/linux/pthread_getname.c (pthread_getname_np)
* sysdeps/unix/sysv/linux/i386/smp.h (is_smp_system):
Use __open64_nocancel instead of __open_nocancel.
* sysdeps/unix/sysv/linux/not-cancel.h: Move all of the
hidden_proto declarations to the end and issue them if either
IS_IN(libc) or IS_IN(rtld).
* sysdeps/unix/sysv/linux/Makefile [subdir=io] (sysdep_routines):
Add close_nocancel, fcntl_nocancel, nanosleep_nocancel,
open_nocancel, open64_nocancel, openat_nocancel, pause_nocancel,
read_nocancel, waitpid_nocancel, write_nocancel.
* io/Versions [GLIBC_PRIVATE]: Add __libc_fcntl,
__fcntl_nocancel, __open64_nocancel, __write_nocancel.
* posix/Versions: Add __nanosleep_nocancel, __pause_nocancel.
* nptl/pt-fcntl.c: New file.
* nptl/Makefile (pthread-compat-wrappers): Remove fcntl.
(libpthread-routines): Add pt-fcntl.
* include/fcntl.h (__fcntl_nocancel_adjusted): New function.
(__libc_fcntl): Remove attribute_hidden.
* sysdeps/unix/sysv/linux/fcntl.c (__libc_fcntl): Call
__fcntl_nocancel_adjusted, not fcntl_common.
(__fcntl_nocancel): Move to new file fcntl_nocancel.c.
(fcntl_common): Rename to __fcntl_nocancel_adjusted; also move
to fcntl_nocancel.c.
* sysdeps/unix/sysv/linux/fcntl_nocancel.c: New file.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/fcntl.c: Remove file.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/sysdep.h:
Define FCNTL_ADJUST_CMD here, as a self-contained macro.
* sysdeps/unix/sysv/linux/close.c: Move __close_nocancel to...
* sysdeps/unix/sysv/linux/close_nocancel.c: ...this new file.
* sysdeps/unix/sysv/linux/nanosleep.c: Move __nanosleep_nocancel to...
* sysdeps/unix/sysv/linux/nanosleep_nocancel.c: ...this new file.
* sysdeps/unix/sysv/linux/open.c: Move __open_nocancel to...
* sysdeps/unix/sysv/linux/open_nocancel.c: ...this new file.
* sysdeps/unix/sysv/linux/open64.c: Move __open64_nocancel to...
* sysdeps/unix/sysv/linux/open64_nocancel.c: ...this new file.
* sysdeps/unix/sysv/linux/openat.c: Move __openat_nocancel to...
* sysdeps/unix/sysv/linux/openat_nocancel.c: ...this new file.
* sysdeps/unix/sysv/linux/openat64.c: Move __openat64_nocancel to...
* sysdeps/unix/sysv/linux/openat64_nocancel.c: ...this new file.
* sysdeps/unix/sysv/linux/pause.c: Move __pause_nocancel to...
* sysdeps/unix/sysv/linux/pause_nocancel.c: ...this new file.
* sysdeps/unix/sysv/linux/read.c: Move __read_nocancel to...
* sysdeps/unix/sysv/linux/read_nocancel.c: ...this new file.
* sysdeps/unix/sysv/linux/waitpid.c: Move __waitpid_nocancel to...
* sysdeps/unix/sysv/linux/waitpid_nocancel.c: ...this new file.
* sysdeps/unix/sysv/linux/write.c: Move __write_nocancel to...
* sysdeps/unix/sysv/linux/write_nocancel.c: ...this new file.
* sysdeps/unix/sysv/linux/nios2/Makefile: Don't override
libpthread-routines.
* sysdeps/unix/sysv/linux/nios2/pt-vfork.S: New file which
defines nothing.
* sysdeps/mach/hurd/dl-sysdep.c: Define __read instead of
__libc_read, and __write instead of __libc_write. Define
__open64 in addition to __open.
The NO_CANCELLATION macro is used currently on generic headers to
define non cancellable syscalls and on Linux fcntl to implement the non
cancellable variation. Former should be single-handled by not-cancel.h
header and former could be simplified build both cancellable and non
cancellable for default objects and alias the non-cancellable to default
one for rtld ones (since Linux already support cancellation as default).
This patch thus removes the NO_CANCELLATION macro and its usage. The
generic non cancellable fcntl is route to internal fcntl.
Checked on x86_64-linux-gnu and i686-linux-gnu. Also checked with
a build again major ABIs.
* sysdeps/generic/not-cancel.h (NO_CANCELLATION): Remove macro.
* sysdeps/unix/sysv/linux/aarch64/sysdep-cancel.h (NO_CANCELLATION):
Likewise.
* sysdeps/unix/sysv/linux/alpha/sysdep-cancel.h (NO_CANCELLATION):
Likewise.
* sysdeps/unix/sysv/linux/arm/sysdep-cancel.h (NO_CANCELLATION):
Likewise.
* sysdeps/unix/sysv/linux/hppa/sysdep-cancel.h (NO_CANCELLATION):
Likewise.
* sysdeps/unix/sysv/linux/i386/sysdep-cancel.h (NO_CANCELLATION):
Likewise.
* sysdeps/unix/sysv/linux/ia64/sysdep-cancel.h (NO_CANCELLATION):
Likewise.
* sysdeps/unix/sysv/linux/m68k/sysdep-cancel.h (NO_CANCELLATION):
Likewise.
* sysdeps/unix/sysv/linux/microblaze/sysdep-cancel.h
(NO_CANCELLATION): Likewise.
* sysdeps/unix/sysv/linux/mips/sysdep-cancel.h (NO_CANCELLATION):
Likewise.
* sysdeps/unix/sysv/linux/nios2/sysdep-cancel.h (NO_CANCELLATION):
Likewise.
* sysdeps/unix/sysv/linux/powerpc/sysdep-cancel.h (NO_CANCELLATION):
Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/sysdep-cancel.h
(NO_CANCELLATION): Likewise.
* sysdeps/unix/sysv/linux/s390/s390-64/sysdep-cancel.h
(NO_CANCELLATION): Likewise.
* sysdeps/unix/sysv/linux/sh/sysdep-cancel.h (NO_CANCELLATION):
Likewise
* sysdeps/unix/sysv/linux/sparc/sysdep-cancel.h (NO_CANCELLATION):
Likewise.
* sysdeps/unix/sysv/linux/tile/sysdep-cancel.h (NO_CANCELLATION):
Likewise.
* sysdeps/unix/sysv/linux/x86_64/sysdep-cancel.h (NO_CANCELLATION):
Likewise.
* sysdeps/unix/sysv/linux/not-cancel.h (__fcntl_nocancel): Add
hidden prototype.
* sysdeps/unix/sysv/linux/fcntl.c (__fcntl_nocancel): Define only
for !IS_IN (rtld) and remove NO_CANCELLATION usage.
This patch removes __ASSUME_F_GETOWN_EX now it can be assumed to be
true unconditionally.
Tested x86_64 that disassembly of installed shared libraries is
unchanged by this patch.
* sysdeps/unix/sysv/linux/kernel-features.h
(__ASSUME_F_GETOWN_EX): Remove macro.
* sysdeps/unix/sysv/linux/fcntl.c: Do not include
<kernel-features.h>.
(miss_F_GETOWN_EX): Remove variable or macro.
(do_fcntl): Do not check miss_F_GETOWN_EX.
(do_fcntl) [!__ASSUME_F_GETOWN_EX]: Remove conditional code.
The syscall conventions on some Linux archs prevented F_GETOWN from working
correctly in some situations. This can be rectified when using the new
F_GETOWN_EX command.
* sysdeps/unix/sysv/linux/fcntl.c (__fcntl_nocancel): Remove
static inline __attribute ((always_inline)). Don't define if
NO_CANCELLATION.
(__libc_fcntl): Use INLINE_SYSCALL directly instead of
__fcntl_nocancel.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/fcntl.c (__fcntl_nocancel):
Remove static inline __attribute ((always_inline)). Don't define
if NO_CANCELLATION.
(__libc_fcntl): Use INLINE_SYSCALL directly instead of
__fcntl_nocancel.
* sysdeps/unix/sysv/linux/i386/fcntl.c (__fcntl_nocancel): Define to
__libc_fcntl if NO_CANCELLATION and __ASSUME_FCNTL64 == 0.
Don't define at all if NO_CANCELLATION and __ASSUME_FCNTL64 > 0.
(__libc_fcntl): Don't define if __fcntl_nocancel is a macro.
2004-07-09 Ulrich Drepper <drepper@redhat.com>
* sysdeps/unix/sysv/linux/fcntl.c (__fcntl_nocancel): Move attribute
to the front for gcc 3.5+.
* sysdeps/unix/sysv/linux/i386/fcntl.c: Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/fcntl.c: Likewise.
* include/fcntl.h: Don't declare __fcntl_nocancel here if
NO_CANCELLATION is defined.
2004-07-05 Ulrich Drepper <drepper@redhat.com>
* elf/dl-init.c: Don't define and use _dl_starting_up if
HAVE_INLINED_SYSCALLS is defined and the variable is not used.
* elf/dl-support.c: Likewise.
* elf/rtld.c: Likewise.
* elf/dl-misc.c (_dl_debug_vdprintf): Use writev syscall directly
if HAVE_INLINED_SYSCALLS is defined.
* sysdeps/powerpc/powerpc64/dl-machine.h: Don't rest _dl_starting_up
here.
* sysdeps/powerpc/powerpc32/dl-start.S: Likewise.
* sysdeps/unix/sysv/linux/configure.in: Define HAVE_INLINED_SYSCALLS.
* config.h.in: Add entry for HAVE_INLINED_SYSCALLS.
* sysdeps/posix/profil.c: If compiled for ld.so, omit code which
is needed to stop profiling.
* elf/dl-open.c (dl_open_worker): If a newly opened object is to be
profile make sure it cannot be unloaded.
* sysdeps/unix/sysv/linux/dl-origin.c: Inline readlink syscall.
* sysdeps/unix/sysv/linux/fcntl.c: If compiled without cancellation
support, make sure the helper function is inlined.
* sysdeps/unix/sysv/linux/pread.c: Likewise.
* sysdeps/unix/sysv/linux/pwrite.c: Likewise.
* sysdeps/unix/sysv/linux/i386/fcntl.c: Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/fcntl.c: Likewise.
* sysdeps/generic/utmp_file.c: Use not-cancelable syscalls all
over the place. It would be allowed to have these fucntions as
cancellation points but the cleanup would be ugly and a lot of
work.
* sysdeps/generic/not-cancel.h (fcntl_not_cancel): Define.
* sysdeps/unix/sysv/linux/not-cancel.h (fcntl_not_cancel): Define.
* include/fcntl.h (__fcntl_nocancel): Declare.
* sysdeps/unix/sysv/linux/fcntl.c: New file.
* sysdeps/unix/sysv/linux/i386/fcntl.c (__libc_fcntl): Only enable
cancellation if absolutely needed.
(__fcntl_nocancel): Define.
* posix/unistd.h (gethostid): Remove __THROW. Clarify comment.
* sysdeps/unix/sysv/linux/Makefile (CFLAGS-gethostid.c): Add
-fexceptions.
* sysdeps/unix/sysv/linux/gethostid.c (gethostid): Use
extend_alloca.
* resolv/res_init.c (__res_nclose): Use close_not_cancel_no_status
instead of __close.
