/* * Based on arch/arm/kernel/sys_arm.c * * Copyright (C) People who wrote linux/arch/i386/kernel/sys_i386.c * Copyright (C) 1995, 1996 Russell King. * Copyright (C) 2012 ARM Ltd. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see <http://www.gnu.org/licenses/>. */#include <linux/compat.h>#include <linux/personality.h>#include <linux/sched.h>#include <linux/sched/signal.h>#include <linux/slab.h>#include <linux/syscalls.h>#include <linux/uaccess.h>#include <asm/cacheflush.h>#include <asm/unistd.h>static long__do_compat_cache_op(unsigned long start, unsigned long end){ long ret; do { unsigned long chunk = min(PAGE_SIZE, end - start); if (fatal_signal_pending(current)) return 0; ret = __flush_cache_user_range(start, start + chunk); if (ret) return ret; cond_resched(); start += chunk; } while (start < end); return 0;}static inline longdo_compat_cache_op(unsigned long start, unsigned long end, int flags){ if (end < start || flags) return -EINVAL; if (!access_ok(VERIFY_READ, start, end - start)) return -EFAULT; return __do_compat_cache_op(start, end);}/* * Handle all unrecognised system calls. */long compat_arm_syscall(struct pt_regs *regs){ unsigned int no = regs->regs[7]; switch (no) { /* * Flush a region from virtual address 'r0' to virtual address 'r1' * _exclusive_. There is no alignment requirement on either address; * user space does not need to know the hardware cache layout. * * r2 contains flags. It should ALWAYS be passed as ZERO until it * is defined to be something else. For now we ignore it, but may * the fires of hell burn in your belly if you break this rule. ;) * * (at a later date, we may want to allow this call to not flush * various aspects of the cache. Passing '0' will guarantee that * everything necessary gets flushed to maintain consistency in * the specified region). */ case __ARM_NR_compat_cacheflush: return do_compat_cache_op(regs->regs[0], regs->regs[1], regs->regs[2]); case __ARM_NR_compat_set_tls: current->thread.tp_value = regs->regs[0]; /* * Protect against register corruption from context switch. * See comment in tls_thread_flush. */ barrier(); write_sysreg(regs->regs[0], tpidrro_el0); return 0; default: return -ENOSYS; }}
/*
* Based on arch/arm/kernel/sys_arm.c
*
* Copyright (C) People who wrote linux/arch/i386/kernel/sys_i386.c
* Copyright (C) 1995, 1996 Russell King.
* Copyright (C) 2012 ARM Ltd.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <linux/compat.h>
#include <linux/personality.h>
#include <linux/sched.h>
#include <linux/sched/signal.h>
#include <linux/slab.h>
#include <linux/syscalls.h>
#include <linux/uaccess.h>
#include <asm/cacheflush.h>
#include <asm/unistd.h>
static long
__do_compat_cache_op(unsigned long start, unsigned long end)
{
long ret;
do {
unsigned long chunk = min(PAGE_SIZE, end - start);
if (fatal_signal_pending(current))
return 0;
ret = __flush_cache_user_range(start, start + chunk);
if (ret)
return ret;
cond_resched();
start += chunk;
} while (start < end);
return 0;
}
static inline long
do_compat_cache_op(unsigned long start, unsigned long end, int flags)
{
if (end < start || flags)
return -EINVAL;
if (!access_ok(VERIFY_READ, start, end - start))
return -EFAULT;
return __do_compat_cache_op(start, end);
}
/*
* Handle all unrecognised system calls.
*/
long compat_arm_syscall(struct pt_regs *regs)
{
unsigned int no = regs->regs[7];
switch (no) {
/*
* Flush a region from virtual address 'r0' to virtual address 'r1'
* _exclusive_. There is no alignment requirement on either address;
* user space does not need to know the hardware cache layout.
*
* r2 contains flags. It should ALWAYS be passed as ZERO until it
* is defined to be something else. For now we ignore it, but may
* the fires of hell burn in your belly if you break this rule. ;)
*
* (at a later date, we may want to allow this call to not flush
* various aspects of the cache. Passing '0' will guarantee that
* everything necessary gets flushed to maintain consistency in
* the specified region).
*/
case __ARM_NR_compat_cacheflush:
return do_compat_cache_op(regs->regs[0], regs->regs[1], regs->regs[2]);
case __ARM_NR_compat_set_tls:
current->thread.tp_value = regs->regs[0];
/*
* Protect against register corruption from context switch.
* See comment in tls_thread_flush.
*/
barrier();
write_sysreg(regs->regs[0], tpidrro_el0);
return 0;
default:
return -ENOSYS;
}
}