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torvalds
GitHub Repository: torvalds/linux
 Path: blob/master/arch/xtensa/kernel/syscall.c
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/*

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 * arch/xtensa/kernel/syscall.c

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 *

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 * This file is subject to the terms and conditions of the GNU General Public

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 * License.  See the file "COPYING" in the main directory of this archive

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 * for more details.

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 *

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 * Copyright (C) 2001 - 2005 Tensilica Inc.

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 * Copyright (C) 2000 Silicon Graphics, Inc.

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 * Copyright (C) 1995 - 2000 by Ralf Baechle

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 *

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 * Joe Taylor <[email protected], [email protected]>

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 * Marc Gauthier <[email protected], [email protected]>

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 * Chris Zankel <[email protected]>

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 * Kevin Chea

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 *

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 */

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#include <linux/uaccess.h>

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#include <asm/syscall.h>

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#include <linux/linkage.h>

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#include <linux/stringify.h>

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#include <linux/errno.h>

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#include <linux/syscalls.h>

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#include <linux/file.h>

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#include <linux/fs.h>

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#include <linux/mman.h>

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#include <linux/sched/mm.h>

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#include <linux/shm.h>

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syscall_t sys_call_table[] /* FIXME __cacheline_aligned */= {

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#define __SYSCALL(nr, entry)	(syscall_t)entry,

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#include <asm/syscall_table.h>

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};

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#define COLOUR_ALIGN(addr, pgoff) \

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	((((addr) + SHMLBA - 1) & ~(SHMLBA - 1)) + \

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	 (((pgoff) << PAGE_SHIFT) & (SHMLBA - 1)))

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asmlinkage long xtensa_shmat(int shmid, char __user *shmaddr, int shmflg)

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{

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	unsigned long ret;

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	long err;

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	err = do_shmat(shmid, shmaddr, shmflg, &ret, SHMLBA);

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	if (err)

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		return err;

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	return (long)ret;

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}

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asmlinkage long xtensa_fadvise64_64(int fd, int advice,

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		unsigned long long offset, unsigned long long len)

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{

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	return ksys_fadvise64_64(fd, offset, len, advice);

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}

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#ifdef CONFIG_MMU

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unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr,

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		unsigned long len, unsigned long pgoff, unsigned long flags,

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		vm_flags_t vm_flags)

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{

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	struct vm_area_struct *vmm;

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	struct vma_iterator vmi;

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	if (flags & MAP_FIXED) {

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		/* We do not accept a shared mapping if it would violate

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		 * cache aliasing constraints.

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		 */

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		if ((flags & MAP_SHARED) &&

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				((addr - (pgoff << PAGE_SHIFT)) & (SHMLBA - 1)))

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			return -EINVAL;

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		return addr;

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	}

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	if (len > TASK_SIZE)

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		return -ENOMEM;

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	if (!addr)

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		addr = TASK_UNMAPPED_BASE;

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	if (flags & MAP_SHARED)

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		addr = COLOUR_ALIGN(addr, pgoff);

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	else

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		addr = PAGE_ALIGN(addr);

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	vma_iter_init(&vmi, current->mm, addr);

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	for_each_vma(vmi, vmm) {

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		/* At this point:  (addr < vmm->vm_end). */

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		if (addr + len <= vm_start_gap(vmm))

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			break;

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		addr = vmm->vm_end;

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		if (flags & MAP_SHARED)

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			addr = COLOUR_ALIGN(addr, pgoff);

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	}

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	if (TASK_SIZE - len < addr)

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		return -ENOMEM;

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	return addr;

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}

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#endif

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