linux_dsm_epyc7002/arch/powerpc/platforms/cell/spu_callbacks.c
Michael Ellerman 454d7ef81a powerpc/syscalls: Add COMPAT_SPU_NEW() macro
Currently the select system call is wired up with the SYSX_SPU()
macro. The SYSX_SPU() is not handled by systbl_chk.c, which means the
syscall number for select is not checked.

That hides the fact that the syscall number for select is actually
__NR__newselect not __NR_select.

In a following patch we'd like to drop ppc32_select() which means
select will become a regular COMPAT_SYS_SPU() syscall. But
COMPAT_SYS_SPU() can't deal with the fact that the syscall number is
actually __NR__newselect. We also can't just redefine __NR_select
because that's still used for the old select call.

So add a new COMPAT_NEW_SPU() that does the same thing as
COMPAT_SYS_SPU() except it encodes that we're using the new number.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-10 23:25:14 +10:00

75 lines
2.1 KiB
C

/*
* System call callback functions for SPUs
*/
#undef DEBUG
#include <linux/kallsyms.h>
#include <linux/export.h>
#include <linux/syscalls.h>
#include <asm/spu.h>
#include <asm/syscalls.h>
#include <asm/unistd.h>
/*
* This table defines the system calls that an SPU can call.
* It is currently a subset of the 64 bit powerpc system calls,
* with the exact semantics.
*
* The reasons for disabling some of the system calls are:
* 1. They interact with the way SPU syscalls are handled
* and we can't let them execute ever:
* restart_syscall, exit, for, execve, ptrace, ...
* 2. They are deprecated and replaced by other means:
* uselib, pciconfig_*, sysfs, ...
* 3. They are somewhat interacting with the system in a way
* we don't want an SPU to:
* reboot, init_module, mount, kexec_load
* 4. They are optional and we can't rely on them being
* linked into the kernel. Unfortunately, the cond_syscall
* helper does not work here as it does not add the necessary
* opd symbols:
* mbind, mq_open, ipc, ...
*/
static void *spu_syscall_table[] = {
#define SYSCALL(func) sys_ni_syscall,
#define COMPAT_SYS(func) sys_ni_syscall,
#define PPC_SYS(func) sys_ni_syscall,
#define OLDSYS(func) sys_ni_syscall,
#define SYS32ONLY(func) sys_ni_syscall,
#define PPC64ONLY(func) sys_ni_syscall,
#define SYSX(f, f3264, f32) sys_ni_syscall,
#define SYSCALL_SPU(func) sys_##func,
#define COMPAT_SYS_SPU(func) sys_##func,
#define COMPAT_SPU_NEW(func) sys_##func,
#define SYSX_SPU(f, f3264, f32) f,
#include <asm/systbl.h>
};
long spu_sys_callback(struct spu_syscall_block *s)
{
long (*syscall)(u64 a1, u64 a2, u64 a3, u64 a4, u64 a5, u64 a6);
if (s->nr_ret >= ARRAY_SIZE(spu_syscall_table)) {
pr_debug("%s: invalid syscall #%lld", __func__, s->nr_ret);
return -ENOSYS;
}
syscall = spu_syscall_table[s->nr_ret];
pr_debug("SPU-syscall "
"%pSR:syscall%lld(%llx, %llx, %llx, %llx, %llx, %llx)\n",
syscall,
s->nr_ret,
s->parm[0], s->parm[1], s->parm[2],
s->parm[3], s->parm[4], s->parm[5]);
return syscall(s->parm[0], s->parm[1], s->parm[2],
s->parm[3], s->parm[4], s->parm[5]);
}
EXPORT_SYMBOL_GPL(spu_sys_callback);