[linux-2.6-block.git] / arch / arc / mm / mmap.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * ARC700 mmap
 *
 * (started from arm version - for VIPT alias handling)
 *
 * Copyright (C) 2013 Synopsys, Inc. (www.synopsys.com)
 */

#include <linux/fs.h>
#include <linux/mm.h>
#include <linux/mman.h>
#include <linux/sched/mm.h>

#include <asm/cacheflush.h>

/*
 * Ensure that shared mappings are correctly aligned to
 * avoid aliasing issues with VIPT caches.
 * We need to ensure that
 * a specific page of an object is always mapped at a multiple of
 * SHMLBA bytes.
 */
unsigned long
arch_get_unmapped_area(struct file *filp, unsigned long addr,
		unsigned long len, unsigned long pgoff, unsigned long flags)
{
	struct mm_struct *mm = current->mm;
	struct vm_area_struct *vma;
	struct vm_unmapped_area_info info = {};

	/*
	 * We enforce the MAP_FIXED case.
	 */
	if (flags & MAP_FIXED) {
		if (flags & MAP_SHARED &&
		    (addr - (pgoff << PAGE_SHIFT)) & (SHMLBA - 1))
			return -EINVAL;
		return addr;
	}

	if (len > TASK_SIZE)
		return -ENOMEM;

	if (addr) {
		addr = PAGE_ALIGN(addr);

		vma = find_vma(mm, addr);
		if (TASK_SIZE - len >= addr &&
		    (!vma || addr + len <= vm_start_gap(vma)))
			return addr;
	}

	info.length = len;
	info.low_limit = mm->mmap_base;
	info.high_limit = TASK_SIZE;
	info.align_offset = pgoff << PAGE_SHIFT;
	return vm_unmapped_area(&info);
}

static const pgprot_t protection_map[16] = {
	[VM_NONE]					= PAGE_U_NONE,
	[VM_READ]					= PAGE_U_R,
	[VM_WRITE]					= PAGE_U_R,
	[VM_WRITE | VM_READ]				= PAGE_U_R,
	[VM_EXEC]					= PAGE_U_X_R,
	[VM_EXEC | VM_READ]				= PAGE_U_X_R,
	[VM_EXEC | VM_WRITE]				= PAGE_U_X_R,
	[VM_EXEC | VM_WRITE | VM_READ]			= PAGE_U_X_R,
	[VM_SHARED]					= PAGE_U_NONE,
	[VM_SHARED | VM_READ]				= PAGE_U_R,
	[VM_SHARED | VM_WRITE]				= PAGE_U_W_R,
	[VM_SHARED | VM_WRITE | VM_READ]		= PAGE_U_W_R,
	[VM_SHARED | VM_EXEC]				= PAGE_U_X_R,
	[VM_SHARED | VM_EXEC | VM_READ]			= PAGE_U_X_R,
	[VM_SHARED | VM_EXEC | VM_WRITE]		= PAGE_U_X_W_R,
	[VM_SHARED | VM_EXEC | VM_WRITE | VM_READ]	= PAGE_U_X_W_R
};
DECLARE_VM_GET_PAGE_PROT
Commit	Line	Data
d2912cb1	1	// SPDX-License-Identifier: GPL-2.0-only
5bba49f5 VG	2	/*
	3	* ARC700 mmap
	4	*
	5	* (started from arm version - for VIPT alias handling)
	6	*
	7	* Copyright (C) 2013 Synopsys, Inc. (www.synopsys.com)
5bba49f5 VG	8	*/
	9
	10	#include <linux/fs.h>
	11	#include <linux/mm.h>
	12	#include <linux/mman.h>
01042607 IM	13	#include <linux/sched/mm.h>
01042607 IM	14
5bba49f5 VG	15	#include <asm/cacheflush.h>
5bba49f5 VG	16
5bba49f5 VG	17	/*
	18	* Ensure that shared mappings are correctly aligned to
	19	* avoid aliasing issues with VIPT caches.
	20	* We need to ensure that
	21	* a specific page of an object is always mapped at a multiple of
	22	* SHMLBA bytes.
	23	*/
	24	unsigned long
	25	arch_get_unmapped_area(struct file *filp, unsigned long addr,
	26	unsigned long len, unsigned long pgoff, unsigned long flags)
	27	{
	28	struct mm_struct *mm = current->mm;
	29	struct vm_area_struct *vma;
b80fa3cb	30	struct vm_unmapped_area_info info = {};
5bba49f5	31
5bba49f5 VG	32	/*
	33	* We enforce the MAP_FIXED case.
	34	*/
	35	if (flags & MAP_FIXED) {
6732c0e4	36	if (flags & MAP_SHARED &&
5bba49f5 VG	37	(addr - (pgoff << PAGE_SHIFT)) & (SHMLBA - 1))
	38	return -EINVAL;
	39	return addr;
	40	}
	41
	42	if (len > TASK_SIZE)
	43	return -ENOMEM;
	44
	45	if (addr) {
6732c0e4	46	addr = PAGE_ALIGN(addr);
5bba49f5 VG	47
	48	vma = find_vma(mm, addr);
	49	if (TASK_SIZE - len >= addr &&
1be7107f	50	(!vma \|\| addr + len <= vm_start_gap(vma)))
5bba49f5 VG	51	return addr;
	52	}
	53
5bba49f5 VG	54	info.length = len;
	55	info.low_limit = mm->mmap_base;
	56	info.high_limit = TASK_SIZE;
5bba49f5 VG	57	info.align_offset = pgoff << PAGE_SHIFT;
	58	return vm_unmapped_area(&info);
	59	}
5d260625 AK	60
	61	static const pgprot_t protection_map[16] = {
	62	[VM_NONE] = PAGE_U_NONE,
	63	[VM_READ] = PAGE_U_R,
	64	[VM_WRITE] = PAGE_U_R,
	65	[VM_WRITE \| VM_READ] = PAGE_U_R,
	66	[VM_EXEC] = PAGE_U_X_R,
	67	[VM_EXEC \| VM_READ] = PAGE_U_X_R,
	68	[VM_EXEC \| VM_WRITE] = PAGE_U_X_R,
	69	[VM_EXEC \| VM_WRITE \| VM_READ] = PAGE_U_X_R,
	70	[VM_SHARED] = PAGE_U_NONE,
	71	[VM_SHARED \| VM_READ] = PAGE_U_R,
	72	[VM_SHARED \| VM_WRITE] = PAGE_U_W_R,
	73	[VM_SHARED \| VM_WRITE \| VM_READ] = PAGE_U_W_R,
	74	[VM_SHARED \| VM_EXEC] = PAGE_U_X_R,
	75	[VM_SHARED \| VM_EXEC \| VM_READ] = PAGE_U_X_R,
	76	[VM_SHARED \| VM_EXEC \| VM_WRITE] = PAGE_U_X_W_R,
	77	[VM_SHARED \| VM_EXEC \| VM_WRITE \| VM_READ] = PAGE_U_X_W_R
	78	};
	79	DECLARE_VM_GET_PAGE_PROT