cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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syscall.c (2392B)

      1/*
      2 * arch/xtensa/kernel/syscall.c
      3 *
      4 * This file is subject to the terms and conditions of the GNU General Public
      5 * License.  See the file "COPYING" in the main directory of this archive
      6 * for more details.
      7 *
      8 * Copyright (C) 2001 - 2005 Tensilica Inc.
      9 * Copyright (C) 2000 Silicon Graphics, Inc.
     10 * Copyright (C) 1995 - 2000 by Ralf Baechle
     11 *
     12 * Joe Taylor <joe@tensilica.com, joetylr@yahoo.com>
     13 * Marc Gauthier <marc@tensilica.com, marc@alumni.uwaterloo.ca>
     14 * Chris Zankel <chris@zankel.net>
     15 * Kevin Chea
     16 *
     17 */
     18#include <linux/uaccess.h>
     19#include <asm/syscall.h>
     20#include <linux/linkage.h>
     21#include <linux/stringify.h>
     22#include <linux/errno.h>
     23#include <linux/syscalls.h>
     24#include <linux/file.h>
     25#include <linux/fs.h>
     26#include <linux/mman.h>
     27#include <linux/sched/mm.h>
     28#include <linux/shm.h>
     29
     30syscall_t sys_call_table[] /* FIXME __cacheline_aligned */= {
     31#define __SYSCALL(nr, entry)	(syscall_t)entry,
     32#include <asm/syscall_table.h>
     33};
     34
     35#define COLOUR_ALIGN(addr, pgoff) \
     36	((((addr) + SHMLBA - 1) & ~(SHMLBA - 1)) + \
     37	 (((pgoff) << PAGE_SHIFT) & (SHMLBA - 1)))
     38
     39asmlinkage long xtensa_shmat(int shmid, char __user *shmaddr, int shmflg)
     40{
     41	unsigned long ret;
     42	long err;
     43
     44	err = do_shmat(shmid, shmaddr, shmflg, &ret, SHMLBA);
     45	if (err)
     46		return err;
     47	return (long)ret;
     48}
     49
     50asmlinkage long xtensa_fadvise64_64(int fd, int advice,
     51		unsigned long long offset, unsigned long long len)
     52{
     53	return ksys_fadvise64_64(fd, offset, len, advice);
     54}
     55
     56#ifdef CONFIG_MMU
     57unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr,
     58		unsigned long len, unsigned long pgoff, unsigned long flags)
     59{
     60	struct vm_area_struct *vmm;
     61
     62	if (flags & MAP_FIXED) {
     63		/* We do not accept a shared mapping if it would violate
     64		 * cache aliasing constraints.
     65		 */
     66		if ((flags & MAP_SHARED) &&
     67				((addr - (pgoff << PAGE_SHIFT)) & (SHMLBA - 1)))
     68			return -EINVAL;
     69		return addr;
     70	}
     71
     72	if (len > TASK_SIZE)
     73		return -ENOMEM;
     74	if (!addr)
     75		addr = TASK_UNMAPPED_BASE;
     76
     77	if (flags & MAP_SHARED)
     78		addr = COLOUR_ALIGN(addr, pgoff);
     79	else
     80		addr = PAGE_ALIGN(addr);
     81
     82	for (vmm = find_vma(current->mm, addr); ; vmm = vmm->vm_next) {
     83		/* At this point:  (!vmm || addr < vmm->vm_end). */
     84		if (TASK_SIZE - len < addr)
     85			return -ENOMEM;
     86		if (!vmm || addr + len <= vm_start_gap(vmm))
     87			return addr;
     88		addr = vmm->vm_end;
     89		if (flags & MAP_SHARED)
     90			addr = COLOUR_ALIGN(addr, pgoff);
     91	}
     92}
     93#endif