Commit Graph

89 Commits

Author SHA1 Message Date
Al Viro
bd1c149aa9 Introduce [compat_]save_altstack_ex() to unbreak x86 SMAP
For performance reasons, when SMAP is in use, SMAP is left open for an
entire put_user_try { ... } put_user_catch(); block, however, calling
__put_user() in the middle of that block will close SMAP as the
STAC..CLAC constructs intentionally do not nest.

Furthermore, using __put_user() rather than put_user_ex() here is bad
for performance.

Thus, introduce new [compat_]save_altstack_ex() helpers that replace
__[compat_]save_altstack() for x86, being currently the only
architecture which supports put_user_try { ... } put_user_catch().

Reported-by: H. Peter Anvin <hpa@linux.intel.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: <stable@vger.kernel.org> # v3.8+
Link: http://lkml.kernel.org/n/tip-es5p6y64if71k8p5u08agv9n@git.kernel.org
2013-09-01 14:16:33 -07:00
Al Viro
91c2e0bcae unify compat fanotify_mark(2), switch to COMPAT_SYSCALL_DEFINE
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-05-09 13:46:38 -04:00
Linus Torvalds
08d7676083 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal
Pull compat cleanup from Al Viro:
 "Mostly about syscall wrappers this time; there will be another pile
  with patches in the same general area from various people, but I'd
  rather push those after both that and vfs.git pile are in."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal:
  syscalls.h: slightly reduce the jungles of macros
  get rid of union semop in sys_semctl(2) arguments
  make do_mremap() static
  sparc: no need to sign-extend in sync_file_range() wrapper
  ppc compat wrappers for add_key(2) and request_key(2) are pointless
  x86: trim sys_ia32.h
  x86: sys32_kill and sys32_mprotect are pointless
  get rid of compat_sys_semctl() and friends in case of ARCH_WANT_OLD_COMPAT_IPC
  merge compat sys_ipc instances
  consolidate compat lookup_dcookie()
  convert vmsplice to COMPAT_SYSCALL_DEFINE
  switch getrusage() to COMPAT_SYSCALL_DEFINE
  switch epoll_pwait to COMPAT_SYSCALL_DEFINE
  convert sendfile{,64} to COMPAT_SYSCALL_DEFINE
  switch signalfd{,4}() to COMPAT_SYSCALL_DEFINE
  make SYSCALL_DEFINE<n>-generated wrappers do asmlinkage_protect
  make HAVE_SYSCALL_WRAPPERS unconditional
  consolidate cond_syscall and SYSCALL_ALIAS declarations
  teach SYSCALL_DEFINE<n> how to deal with long long/unsigned long long
  get rid of duplicate logics in __SC_....[1-6] definitions
2013-05-01 07:21:43 -07:00
David Howells
2a1486981c Fix breakage in MIPS siginfo handling
MIPS's siginfo handling has been broken since this commit:

	commit 574c4866e3
	Author: Al Viro <viro@zeniv.linux.org.uk>
	Date:   Sun Nov 25 22:24:19 2012 -0500
	consolidate kernel-side struct sigaction declarations

for 64-bit BE MIPS CPUs.

The UAPI variant looks like this:

	struct sigaction {
		unsigned int	sa_flags;
		__sighandler_t	sa_handler;
		sigset_t	sa_mask;
	};

but the core kernel's variant looks like this:

	struct sigaction {
	#ifndef __ARCH_HAS_ODD_SIGACTION
		__sighandler_t	sa_handler;
		unsigned long	sa_flags;
	#else
		unsigned long	sa_flags;
		__sighandler_t	sa_handler;
	#endif
	#ifdef __ARCH_HAS_SA_RESTORER
		__sigrestore_t sa_restorer;
	#endif
		sigset_t	sa_mask;
	};

The problem is that sa_flags has been changed from an unsigned int to an
unsigned long.

Fix this by making sa_flags unsigned int if __ARCH_HAS_ODD_SIGACTION is
defined.

Whilst we're at it, rename __ARCH_HAS_ODD_SIGACTION to
__ARCH_HAS_IRIX_SIGACTION.

Signed-off-by: David Howells <dhowells@redhat.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Cc: stable@vger.kernel.org
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-03-19 19:15:52 +01:00
Al Viro
0e65a81b10 get rid of compat_sys_semctl() and friends in case of ARCH_WANT_OLD_COMPAT_IPC
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-03-03 23:00:27 -05:00
Al Viro
56e41d3c5a merge compat sys_ipc instances
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-03-03 23:00:27 -05:00
Al Viro
d5dc77bfee consolidate compat lookup_dcookie()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-03-03 23:00:23 -05:00
Al Viro
35280bd4a3 switch epoll_pwait to COMPAT_SYSCALL_DEFINE
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-03-03 22:58:49 -05:00
Al Viro
19f4fc3aee convert sendfile{,64} to COMPAT_SYSCALL_DEFINE
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-03-03 22:58:46 -05:00
Al Viro
22d1a35da0 make HAVE_SYSCALL_WRAPPERS unconditional
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-03-03 22:58:30 -05:00
Al Viro
07fe6e00f6 get rid of duplicate logics in __SC_....[1-6] definitions
All those guys have the same form - "take a list of type/name pairs,
apply some macro to each of them".  Abstract that part away, convert
all __SC_FOO##x(__VA_ARGS__) to __MAP(x,__SC_FOO,__VA_ARGS__).

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-03-03 22:46:21 -05:00
Al Viro
3f6d078d4a fix compat truncate/ftruncate
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-25 09:24:55 -05:00
Al Viro
561c673197 switch lseek to COMPAT_SYSCALL_DEFINE
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-24 10:52:26 -05:00
Al Viro
d64008a8f3 burying unused conditionals
__ARCH_WANT_SYS_RT_SIGACTION,
__ARCH_WANT_SYS_RT_SIGSUSPEND,
__ARCH_WANT_COMPAT_SYS_RT_SIGSUSPEND,
__ARCH_WANT_COMPAT_SYS_SCHED_RR_GET_INTERVAL - not used anymore
CONFIG_GENERIC_{SIGALTSTACK,COMPAT_RT_SIG{ACTION,QUEUEINFO,PENDING,PROCMASK}} -
can be assumed always set.
2013-02-14 09:21:15 -05:00
Al Viro
f482e1b4a4 switch compat_sys_open* to COMPAT_SYSCALL_DEFINE 2013-02-03 15:09:24 -05:00
Al Viro
495dfbf767 generic sys_sigaction() and compat_sys_sigaction()
conditional on OLD_SIGACTION/COMPAT_OLD_SIGACTION

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-03 15:09:23 -05:00
Al Viro
08d32fe504 generic sys_compat_rt_sigaction()
Again, protected by a temporary config symbol (GENERIC_COMPAT_RT_SIGACTION);
will be gone by the end of series.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-03 15:09:23 -05:00
Al Viro
75907d4d7b generic compat_sys_rt_sigqueueinfo()
conditional on GENERIC_COMPAT_RT_SIGQUEUEINFO; by the end of that series
it will become the same thing as COMPAT and conditional will die out.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-03 15:09:19 -05:00
Al Viro
fe9c1db2cf generic compat_sys_rt_sigpending()
conditional on GENERIC_COMPAT_RT_SIGPENDING; by the end of that series
it will become the same thing as COMPAT and conditional will die out.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-03 15:09:19 -05:00
Al Viro
322a56cb1f generic compat_sys_rt_sigprocmask()
conditional on GENERIC_COMPAT_RT_SIGPROCMASK; by the end of that series
it will become the same thing as COMPAT and conditional will die out.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-03 15:09:19 -05:00
Linus Torvalds
54d46ea993 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal
Pull signal handling cleanups from Al Viro:
 "sigaltstack infrastructure + conversion for x86, alpha and um,
  COMPAT_SYSCALL_DEFINE infrastructure.

  Note that there are several conflicts between "unify
  SS_ONSTACK/SS_DISABLE definitions" and UAPI patches in mainline;
  resolution is trivial - just remove definitions of SS_ONSTACK and
  SS_DISABLED from arch/*/uapi/asm/signal.h; they are all identical and
  include/uapi/linux/signal.h contains the unified variant."

Fixed up conflicts as per Al.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal:
  alpha: switch to generic sigaltstack
  new helpers: __save_altstack/__compat_save_altstack, switch x86 and um to those
  generic compat_sys_sigaltstack()
  introduce generic sys_sigaltstack(), switch x86 and um to it
  new helper: compat_user_stack_pointer()
  new helper: restore_altstack()
  unify SS_ONSTACK/SS_DISABLE definitions
  new helper: current_user_stack_pointer()
  missing user_stack_pointer() instances
  Bury the conditionals from kernel_thread/kernel_execve series
  COMPAT_SYSCALL_DEFINE: infrastructure
2012-12-20 18:05:28 -08:00
Al Viro
c40702c49f new helpers: __save_altstack/__compat_save_altstack, switch x86 and um to those
note that they are relying on access_ok() already checked by caller.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-12-19 18:07:41 -05:00
Al Viro
9026843952 generic compat_sys_sigaltstack()
Again, conditional on CONFIG_GENERIC_SIGALTSTACK

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-12-19 18:07:41 -05:00
Al Viro
9b064fc3f9 new helper: compat_user_stack_pointer()
Compat counterpart of current_user_stack_pointer(); for most of the biarch
architectures those two are identical, but e.g. arm64 and arm use different
registers for stack pointer...

Note that amd64 variants of current_user_stack_pointer/compat_user_stack_pointer
do *not* rely on pt_regs having been through FIXUP_TOP_OF_STACK.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-12-19 18:07:40 -05:00
Al Viro
4683661388 COMPAT_SYSCALL_DEFINE: infrastructure
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-12-19 18:06:58 -05:00
Catalin Marinas
0ad50c3896 compat: generic compat_sys_sched_rr_get_interval() implementation
This function is used by sparc, powerpc tile and arm64 for compat support.
 The patch adds a generic implementation with a wrapper for PowerPC to do
the u32->int sign extension.

The reason for a single patch covering powerpc, tile, sparc and arm64 is
to keep it bisectable, otherwise kernel building may fail with mismatched
function declarations.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Chris Metcalf <cmetcalf@tilera.com>  [for tile]
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-17 17:15:18 -08:00
Al Viro
d03d26e58f make compat_do_execve() static, lose pt_regs argument
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-11-28 21:53:37 -05:00
Al Viro
733deca197 Drop struct pt_regs * argument in compat_sys_execve()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-10-20 13:13:11 -04:00
Linus Torvalds
42859eea96 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal
Pull generic execve() changes from Al Viro:
 "This introduces the generic kernel_thread() and kernel_execve()
  functions, and switches x86, arm, alpha, um and s390 over to them."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: (26 commits)
  s390: convert to generic kernel_execve()
  s390: switch to generic kernel_thread()
  s390: fold kernel_thread_helper() into ret_from_fork()
  s390: fold execve_tail() into start_thread(), convert to generic sys_execve()
  um: switch to generic kernel_thread()
  x86, um/x86: switch to generic sys_execve and kernel_execve
  x86: split ret_from_fork
  alpha: introduce ret_from_kernel_execve(), switch to generic kernel_execve()
  alpha: switch to generic kernel_thread()
  alpha: switch to generic sys_execve()
  arm: get rid of execve wrapper, switch to generic execve() implementation
  arm: optimized current_pt_regs()
  arm: introduce ret_from_kernel_execve(), switch to generic kernel_execve()
  arm: split ret_from_fork, simplify kernel_thread() [based on patch by rmk]
  generic sys_execve()
  generic kernel_execve()
  new helper: current_pt_regs()
  preparation for generic kernel_thread()
  um: kill thread->forking
  um: let signal_delivered() do SIGTRAP on singlestepping into handler
  ...
2012-10-10 12:02:25 +09:00
Denys Vlasenko
751f409db6 compat: move compat_siginfo_t definition to asm/compat.h
This is a preparatory patch for the introduction of NT_SIGINFO elf note.

Make the location of compat_siginfo_t uniform across eight architectures
which have it.  Now it can be pulled in by including asm/compat.h or
linux/compat.h.

Most of the copies are verbatim.  compat_uid[32]_t had to be replaced by
__compat_uid[32]_t.  compat_uptr_t had to be moved up before
compat_siginfo_t in asm/compat.h on a several architectures (tile already
had it moved up).  compat_sigval_t had to be relocated from linux/compat.h
to asm/compat.h.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Amerigo Wang <amwang@redhat.com>
Cc: "Jonathan M. Foote" <jmfoote@cert.org>
Cc: Roland McGrath <roland@hack.frob.com>
Cc: Pedro Alves <palves@redhat.com>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-06 03:05:16 +09:00
Catalin Marinas
8f9c0119d7 compat: fs: Generic compat_sys_sendfile implementation
This function is used by sparc, powerpc and arm64 for compat support.
The patch adds a generic implementation which calls do_sendfile()
directly and avoids set_fs().

The sparc architecture has wrappers for the sign extensions while
powerpc relies on the compiler to do the this. The patch adds wrappers
for powerpc to handle the u32->int type conversion.

compat_sys_sendfile64() can be replaced by a sys_sendfile() call since
compat_loff_t has the same size as off_t on a 64-bit system.

On powerpc, the patch also changes the 64-bit sendfile call from
sys_sendile64 to sys_sendfile.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: David S. Miller <davem@davemloft.net>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-10-02 21:35:55 -04:00
Al Viro
38b983b346 generic sys_execve()
Selected by __ARCH_WANT_SYS_EXECVE in unistd.h.  Requires
	* working current_pt_regs()
	* *NOT* doing a syscall-in-kernel kind of kernel_execve()
implementation.  Using generic kernel_execve() is fine.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-09-30 22:20:51 -04:00
Will Deacon
c1d7e01d78 ipc: use Kconfig options for __ARCH_WANT_[COMPAT_]IPC_PARSE_VERSION
Rather than #define the options manually in the architecture code, add
Kconfig options for them and select them there instead.  This also allows
us to select the compat IPC version parsing automatically for platforms
using the old compat IPC interface.

Reported-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-30 17:25:21 -07:00
Will Deacon
05ba3f1aa1 ipc: compat: use signed size_t types for msgsnd and msgrcv
The msgsnd and msgrcv system calls use size_t to represent the size of the
message being transferred.  POSIX states that values of msgsz greater than
SSIZE_MAX cause the result to be implementation-defined.  On Linux, this
equates to returning -EINVAL if (long) msgsz < 0.

For compat tasks where !CONFIG_ARCH_WANT_OLD_COMPAT_IPC and compat_size_t
is smaller than size_t, negative size values passed from userspace will be
interpreted as positive values by do_msg{rcv,snd} and will fail to exit
early with -EINVAL.

This patch changes the compat prototypes for msg{rcv,snd} so that the
message size is represented as a compat_ssize_t, which we cast to the
native ssize_t type for the core IPC code.

Cc: Arnd Bergmann <arnd@arndb.de>
Acked-by: Chris Metcalf <cmetcalf@tilera.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-30 17:25:21 -07:00
Will Deacon
b610c04c66 ipc: allow compat IPC version field parsing if !ARCH_WANT_OLD_COMPAT_IPC
Commit 48b25c43e6 ("ipc: provide generic compat versions of IPC
syscalls") added a new ARCH_WANT_OLD_COMPAT_IPC config option for
architectures to select if their compat target requires the old IPC
syscall interface.

For architectures (such as AArch64) that do not require the internal
calling conventions provided by this option, but have a compat target
where the C library passes the IPC_64 flag explicitly,
compat_ipc_parse_version no longer strips out the flag before calling
the native system call implementation, resulting in unknown SHM/IPC
commands and -EINVAL being returned to userspace.

This patch separates the selection of the internal calling conventions
for the IPC syscalls from the version parsing, allowing architectures to
select __ARCH_WANT_COMPAT_IPC_PARSE_VERSION if they want to use version
parsing whilst retaining the newer syscall calling conventions.

Acked-by: Chris Metcalf <cmetcalf@tilera.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-30 17:25:21 -07:00
Christopher Yeoh
ac34ebb3a6 aio/vfs: cleanup of rw_copy_check_uvector() and compat_rw_copy_check_uvector()
A cleanup of rw_copy_check_uvector and compat_rw_copy_check_uvector after
changes made to support CMA in an earlier patch.

Rather than having an additional check_access parameter to these
functions, the first paramater type is overloaded to allow the caller to
specify CHECK_IOVEC_ONLY which means check that the contents of the iovec
are valid, but do not check the memory that they point to.  This is used
by process_vm_readv/writev where we need to validate that a iovec passed
to the syscall is valid but do not want to check the memory that it points
to at this point because it refers to an address space in another process.

Signed-off-by: Chris Yeoh <yeohc@au1.ibm.com>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-31 17:49:32 -07:00
Linus Torvalds
a591afc01d Merge branch 'x86-x32-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x32 support for x86-64 from Ingo Molnar:
 "This tree introduces the X32 binary format and execution mode for x86:
  32-bit data space binaries using 64-bit instructions and 64-bit kernel
  syscalls.

  This allows applications whose working set fits into a 32 bits address
  space to make use of 64-bit instructions while using a 32-bit address
  space with shorter pointers, more compressed data structures, etc."

Fix up trivial context conflicts in arch/x86/{Kconfig,vdso/vma.c}

* 'x86-x32-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (71 commits)
  x32: Fix alignment fail in struct compat_siginfo
  x32: Fix stupid ia32/x32 inversion in the siginfo format
  x32: Add ptrace for x32
  x32: Switch to a 64-bit clock_t
  x32: Provide separate is_ia32_task() and is_x32_task() predicates
  x86, mtrr: Use explicit sizing and padding for the 64-bit ioctls
  x86/x32: Fix the binutils auto-detect
  x32: Warn and disable rather than error if binutils too old
  x32: Only clear TIF_X32 flag once
  x32: Make sure TS_COMPAT is cleared for x32 tasks
  fs: Remove missed ->fds_bits from cessation use of fd_set structs internally
  fs: Fix close_on_exec pointer in alloc_fdtable
  x32: Drop non-__vdso weak symbols from the x32 VDSO
  x32: Fix coding style violations in the x32 VDSO code
  x32: Add x32 VDSO support
  x32: Allow x32 to be configured
  x32: If configured, add x32 system calls to system call tables
  x32: Handle process creation
  x32: Signal-related system calls
  x86: Add #ifdef CONFIG_COMPAT to <asm/sys_ia32.h>
  ...
2012-03-29 18:12:23 -07:00
Chris Metcalf
48b25c43e6 [PATCH v3] ipc: provide generic compat versions of IPC syscalls
When using the "compat" APIs, architectures will generally want to
be able to make direct syscalls to msgsnd(), shmctl(), etc., and
in the kernel we would want them to be handled directly by
compat_sys_xxx() functions, as is true for other compat syscalls.

However, for historical reasons, several of the existing compat IPC
syscalls do not do this.  semctl() expects a pointer to the fourth
argument, instead of the fourth argument itself.  msgsnd(), msgrcv()
and shmat() expect arguments in different order.

This change adds an ARCH_WANT_OLD_COMPAT_IPC config option that can be
set to preserve this behavior for ports that use it (x86, sparc, powerpc,
s390, and mips).  No actual semantics are changed for those architectures,
and there is only a minimal amount of code refactoring in ipc/compat.c.

Newer architectures like tile (and perhaps future architectures such
as arm64 and unicore64) should not select this option, and thus can
avoid having any IPC-specific code at all in their architecture-specific
compat layer.  In the same vein, if this option is not selected, IPC_64
mode is assumed, since that's what the <asm-generic> headers expect.

The workaround code in "tile" for msgsnd() and msgrcv() is removed
with this change; it also fixes the bug that shmat() and semctl() were
not being properly handled.

Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2012-03-15 13:13:38 -04:00
Linus Torvalds
3c761ea05a Fix autofs compile without CONFIG_COMPAT
The autofs compat handling fix caused a compile failure when
CONFIG_COMPAT isn't defined.

Instead of adding random #ifdef'fery in autofs, let's just make the
compat helpers earlier to use: without CONFIG_COMPAT, is_compat_task()
just hardcodes to zero.

We could probably do something similar for a number of other cases where
we have #ifdef's in code, but this is the low-hanging fruit.

Reported-and-tested-by: Andreas Schwab <schwab@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-26 09:44:55 -08:00
H. Peter Anvin
6684ba202b compat: Add helper functions to read/write struct timeval, timespec
Add helper functions to read and write struct timeval and struct
timespec from userspace.  We already had helper functions for reading
and writing struct compat_timespec; add a set of functions to do the
same with struct timeval, and add a second suite of functions which
can be sensitive to COMPAT_USE_64BIT_TIME and access either 32- or
64-bit time structures.

This also exports these helper functions to modules.

Rename the existing inlines for converting between struct
compat_timeval and native struct timespec so we can have a saner
naming convention for the exported functions.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2012-02-20 12:48:47 -08:00
H. J. Lu
45e8778129 compat: Introduce COMPAT_USE_64BIT_TIME
Allow a compatibility ABI to use a 64-bit time_t and 64-bit members in
struct timeval and struct timespec to avoid the Y2038 problem.

This will be used for the x32 ABI.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2012-02-20 12:48:47 -08:00
Al Viro
a218d0fdc5 switch open and mkdir syscalls to umode_t
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03 22:55:19 -05:00
Chris Metcalf
a67ba43d30 asm-generic/unistd.h: support new process_vm_{readv,write} syscalls
Also prototype the "compat" functions so they can be referenced
from C code.

Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2011-12-03 15:31:48 -05:00
Christopher Yeoh
fcf634098c Cross Memory Attach
The basic idea behind cross memory attach is to allow MPI programs doing
intra-node communication to do a single copy of the message rather than a
double copy of the message via shared memory.

The following patch attempts to achieve this by allowing a destination
process, given an address and size from a source process, to copy memory
directly from the source process into its own address space via a system
call.  There is also a symmetrical ability to copy from the current
process's address space into a destination process's address space.

- Use of /proc/pid/mem has been considered, but there are issues with
  using it:
  - Does not allow for specifying iovecs for both src and dest, assuming
    preadv or pwritev was implemented either the area read from or
  written to would need to be contiguous.
  - Currently mem_read allows only processes who are currently
  ptrace'ing the target and are still able to ptrace the target to read
  from the target. This check could possibly be moved to the open call,
  but its not clear exactly what race this restriction is stopping
  (reason  appears to have been lost)
  - Having to send the fd of /proc/self/mem via SCM_RIGHTS on unix
  domain socket is a bit ugly from a userspace point of view,
  especially when you may have hundreds if not (eventually) thousands
  of processes  that all need to do this with each other
  - Doesn't allow for some future use of the interface we would like to
  consider adding in the future (see below)
  - Interestingly reading from /proc/pid/mem currently actually
  involves two copies! (But this could be fixed pretty easily)

As mentioned previously use of vmsplice instead was considered, but has
problems.  Since you need the reader and writer working co-operatively if
the pipe is not drained then you block.  Which requires some wrapping to
do non blocking on the send side or polling on the receive.  In all to all
communication it requires ordering otherwise you can deadlock.  And in the
example of many MPI tasks writing to one MPI task vmsplice serialises the
copying.

There are some cases of MPI collectives where even a single copy interface
does not get us the performance gain we could.  For example in an
MPI_Reduce rather than copy the data from the source we would like to
instead use it directly in a mathops (say the reduce is doing a sum) as
this would save us doing a copy.  We don't need to keep a copy of the data
from the source.  I haven't implemented this, but I think this interface
could in the future do all this through the use of the flags - eg could
specify the math operation and type and the kernel rather than just
copying the data would apply the specified operation between the source
and destination and store it in the destination.

Although we don't have a "second user" of the interface (though I've had
some nibbles from people who may be interested in using it for intra
process messaging which is not MPI).  This interface is something which
hardware vendors are already doing for their custom drivers to implement
fast local communication.  And so in addition to this being useful for
OpenMPI it would mean the driver maintainers don't have to fix things up
when the mm changes.

There was some discussion about how much faster a true zero copy would
go. Here's a link back to the email with some testing I did on that:

http://marc.info/?l=linux-mm&m=130105930902915&w=2

There is a basic man page for the proposed interface here:

http://ozlabs.org/~cyeoh/cma/process_vm_readv.txt

This has been implemented for x86 and powerpc, other architecture should
mainly (I think) just need to add syscall numbers for the process_vm_readv
and process_vm_writev. There are 32 bit compatibility versions for
64-bit kernels.

For arch maintainers there are some simple tests to be able to quickly
verify that the syscalls are working correctly here:

http://ozlabs.org/~cyeoh/cma/cma-test-20110718.tgz

Signed-off-by: Chris Yeoh <yeohc@au1.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Howells <dhowells@redhat.com>
Cc: James Morris <jmorris@namei.org>
Cc: <linux-man@vger.kernel.org>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-10-31 17:30:44 -07:00
NeilBrown
f5b9409973 All Arch: remove linkage for sys_nfsservctl system call
The nfsservctl system call is now gone, so we should remove all
linkage for it.

Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-08-26 15:09:58 -07:00
NeilBrown
49b28684fd nfsd: Remove deprecated nfsctl system call and related code.
As promised in feature-removal-schedule.txt it is time to
remove the nfsctl system call.

Userspace has perferred to not use this call throughout 2.6 and it has been
excluded in the default configuration since 2.6.36 (9 months ago).

So this patch removes all the code that was being compiled out.

There are still references to sys_nfsctl in various arch systemcall tables
and related code.  These should be cleaned out too, probably in the next
merge window.

Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2011-07-15 18:58:42 -04:00
Chris Metcalf
507c5f1224 include/linux/compat.h: declare compat_sys_sendmmsg()
This is required for tilegx to be able to use the compat unistd.h header
where compat_sys_sendmmsg() is now mentioned.

Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-06-27 18:00:13 -07:00
Stephen Rothwell
45e9683e87 compat: include aio_abi.h for aio_context_t
fixes this build error on sparc64 (at least):

In file included from arch/sparc/include/asm/siginfo.h:19,
                 from include/linux/signal.h:5,
                 from include/linux/sched.h:73,
                 from arch/sparc/kernel/asm-offsets.c:13:
include/linux/compat.h:401: error: expected ')' before 'ctx_id'
include/linux/compat.h:406: error: expected ')' before 'ctx_id'

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2011-05-24 08:55:20 -04:00
Chris Metcalf
4800a5bb13 include/linux/compat.h: coding-style fixes
I touched this file when adding support for the "tilegx" sub-architecture,
and Andrew Morton observed "The file's a mismash of old-style, wrong-style
and right-style.  There's no point in doing mishmash preservation!
May as well fix things up when we touch them."

Accordingly, this change makes <linux/compat.h> as checkpatch-clean
as possible.  It makes no semantic changes whatsoever.

Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2011-05-19 22:54:55 -04:00
Chris Metcalf
be84cb4383 compat: fixes to allow working with tile arch
The existing <asm-generic/unistd.h> mechanism doesn't really provide
enough to create the 64-bit "compat" ABI properly in a generic way,
since the compat ABI is a mix of things were you can re-use the 64-bit
versions of syscalls and things where you need a compat wrapper.

To provide this in the most direct way possible, I added two new macros
to go along with the existing __SYSCALL and __SC_3264 macros: __SC_COMP
and SC_COMP_3264.  These macros take an additional argument, typically a
"compat_sys_xxx" function, which is passed to __SYSCALL if you define
__SYSCALL_COMPAT when including the header, resulting in a pointer to
the compat function being placed in the generated syscall table.

The change also adds some missing definitions to <linux/compat.h> so that
it actually has declarations for all the compat syscalls, since the
"[nr] = ##call" approach requires proper C declarations for all the
functions included in the syscall table.

Finally, compat.c defines compat_sys_sigpending() and
compat_sys_sigprocmask() even if the underlying architecture doesn't
request it, which tries to pull in undefined compat_old_sigset_t defines.
We need to guard those compat syscall definitions with appropriate
__ARCH_WANT_SYS_xxx ifdefs.

Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2011-05-12 15:51:36 -04:00