The behavior of these system calls is slightly different between
architectures, as determined by the CONFIG_ARCH_WANT_IPC_PARSE_VERSION
symbol. Most architectures that implement the split IPC syscalls don't set
that symbol and only get the modern version, but alpha, arm, microblaze,
mips-n32, mips-n64 and xtensa expect the caller to pass the IPC_64 flag.
For the architectures that so far only implement sys_ipc(), i.e. m68k,
mips-o32, powerpc, s390, sh, sparc, and x86-32, we want the new behavior
when adding the split syscalls, so we need to distinguish between the
two groups of architectures.
The method I picked for this distinction is to have a separate system call
entry point: sys_old_*ctl() now uses ipc_parse_version, while sys_*ctl()
does not. The system call tables of the five architectures are changed
accordingly.
As an additional benefit, we no longer need the configuration specific
definition for ipc_parse_version(), it always does the same thing now,
but simply won't get called on architectures with the modern interface.
A small downside is that on architectures that do set
ARCH_WANT_IPC_PARSE_VERSION, we now have an extra set of entry points
that are never called. They only add a few bytes of bloat, so it seems
better to keep them compared to adding yet another Kconfig symbol.
I considered adding new syscall numbers for the IPC_64 variants for
consistency, but decided against that for now.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
A couple of architectures including arm64 already implement the
kexec_file_load system call, on many others we have assigned a system
call number for it, but not implemented it yet.
Adding the number in arch/arm/ lets us use the system call on arm64
systems in compat mode, and also reduces the number of differences
between architectures. If we want to implement kexec_file_load on ARM
in the future, the number assignment means that kexec tools can already
be built with the now current set of kernel headers.
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
The migrate_pages system call has an assigned number on all architectures
except ARM. When it got added initially in commit d80ade7b32 ("ARM:
Fix warning: #warning syscall migrate_pages not implemented"), it was
intentionally left out based on the observation that there are no 32-bit
ARM NUMA systems.
However, there are now arm64 NUMA machines that can in theory run 32-bit
kernels (actually enabling NUMA there would require additional work)
as well as 32-bit user space on 64-bit kernels, so that argument is no
longer very strong.
Assigning the number lets us use the system call on 64-bit kernels as well
as providing a more consistent set of syscalls across architectures.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Wire up the new io_pgetevents syscall for ARM.
Signed-off-by: Stefan Agner <stefan@agner.ch>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Wire up the rseq system call on 32-bit ARM.
This provides an ABI improving the speed of a user-space getcpu
operation on ARM by skipping the getcpu system call on the fast path, as
well as improving the speed of user-space operations on per-cpu data
compared to using load-linked/store-conditional.
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Joel Fernandes <joelaf@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dave Watson <davejwatson@fb.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Chris Lameter <cl@linux.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Andrew Hunter <ahh@google.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: "Paul E . McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Paul Turner <pjt@google.com>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ben Maurer <bmaurer@fb.com>
Cc: linux-api@vger.kernel.org
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lkml.kernel.org/r/20180602124408.8430-6-mathieu.desnoyers@efficios.com
Wire up the new pkey syscalls for ARM. This illustrates the ease that
the generated/tabular approach gives us: adding new system calls
becomes much easier, and all the dependencies are automatically handled
for the update.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Convert ARM to use a similar mechanism to x86 to generate the unistd.h
system call numbers and the various kernel system call tables. This
means that rather than having to edit three places (asm/unistd.h for
the total number of system calls, uapi/asm/unistd.h for the system call
numbers, and arch/arm/kernel/calls.S for the call table) we have only
one place to edit, making the process much more simple.
The scripts have knowledge of the table padding requirements, so there's
no need to worry about __NR_syscalls not fitting within the immediate
constant field of ALU instructions anymore.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
