1/*
 2 * Generic page table allocator for IOMMUs.
 3 *
 4 * This program is free software; you can redistribute it and/or modify
 5 * it under the terms of the GNU General Public License version 2 as
 6 * published by the Free Software Foundation.
 7 *
 8 * This program is distributed in the hope that it will be useful,
 9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
11 * GNU General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public License
14 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
15 *
16 * Copyright (C) 2014 ARM Limited
17 *
18 * Author: Will Deacon <will.deacon@arm.com>
19 */
20
21#include <linux/bug.h>
22#include <linux/kernel.h>
23#include <linux/types.h>
24
25#include "io-pgtable.h"
26
27static const struct io_pgtable_init_fns *
28io_pgtable_init_table[IO_PGTABLE_NUM_FMTS] = {
29#ifdef CONFIG_IOMMU_IO_PGTABLE_LPAE
30	[ARM_32_LPAE_S1] = &io_pgtable_arm_32_lpae_s1_init_fns,
31	[ARM_32_LPAE_S2] = &io_pgtable_arm_32_lpae_s2_init_fns,
32	[ARM_64_LPAE_S1] = &io_pgtable_arm_64_lpae_s1_init_fns,
33	[ARM_64_LPAE_S2] = &io_pgtable_arm_64_lpae_s2_init_fns,
34#endif
35#ifdef CONFIG_IOMMU_IO_PGTABLE_ARMV7S
36	[ARM_V7S] = &io_pgtable_arm_v7s_init_fns,
37#endif
38};
39
40struct io_pgtable_ops *alloc_io_pgtable_ops(enum io_pgtable_fmt fmt,
41					    struct io_pgtable_cfg *cfg,
42					    void *cookie)
43{
44	struct io_pgtable *iop;
45	const struct io_pgtable_init_fns *fns;
46
47	if (fmt >= IO_PGTABLE_NUM_FMTS)
48		return NULL;
49
50	fns = io_pgtable_init_table[fmt];
51	if (!fns)
52		return NULL;
53
54	iop = fns->alloc(cfg, cookie);
55	if (!iop)
56		return NULL;
57
58	iop->fmt	= fmt;
59	iop->cookie	= cookie;
60	iop->cfg	= *cfg;
61
62	return &iop->ops;
63}
64
65/*
66 * It is the IOMMU driver's responsibility to ensure that the page table
67 * is no longer accessible to the walker by this point.
68 */
69void free_io_pgtable_ops(struct io_pgtable_ops *ops)
70{
71	struct io_pgtable *iop;
72
73	if (!ops)
74		return;
75
76	iop = container_of(ops, struct io_pgtable, ops);
77	io_pgtable_tlb_flush_all(iop);
78	io_pgtable_init_table[iop->fmt]->free(iop);
79}