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{
30#ifdef CONFIG_IOMMU_IO_PGTABLE_LPAE
31	[ARM_32_LPAE_S1] = &io_pgtable_arm_32_lpae_s1_init_fns,
32	[ARM_32_LPAE_S2] = &io_pgtable_arm_32_lpae_s2_init_fns,
33	[ARM_64_LPAE_S1] = &io_pgtable_arm_64_lpae_s1_init_fns,
34	[ARM_64_LPAE_S2] = &io_pgtable_arm_64_lpae_s2_init_fns,
35#endif
36};
37
38struct io_pgtable_ops *alloc_io_pgtable_ops(enum io_pgtable_fmt fmt,
39					    struct io_pgtable_cfg *cfg,
40					    void *cookie)
41{
42	struct io_pgtable *iop;
43	const struct io_pgtable_init_fns *fns;
44
45	if (fmt >= IO_PGTABLE_NUM_FMTS)
46		return NULL;
47
48	fns = io_pgtable_init_table[fmt];
49	if (!fns)
50		return NULL;
51
52	iop = fns->alloc(cfg, cookie);
53	if (!iop)
54		return NULL;
55
56	iop->fmt	= fmt;
57	iop->cookie	= cookie;
58	iop->cfg	= *cfg;
59
60	return &iop->ops;
61}
62
63/*
64 * It is the IOMMU driver's responsibility to ensure that the page table
65 * is no longer accessible to the walker by this point.
66 */
67void free_io_pgtable_ops(struct io_pgtable_ops *ops)
68{
69	struct io_pgtable *iop;
70
71	if (!ops)
72		return;
73
74	iop = container_of(ops, struct io_pgtable, ops);
75	iop->cfg.tlb->tlb_flush_all(iop->cookie);
76	io_pgtable_init_table[iop->fmt]->free(iop);
77}
78