1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Generic page table allocator for IOMMUs.
4 *
5 * Copyright (C) 2014 ARM Limited
6 *
7 * Author: Will Deacon <will.deacon@arm.com>
8 */
9
10 #include <linux/bug.h>
11 #include <linux/io-pgtable.h>
12 #include <linux/kernel.h>
13 #include <linux/types.h>
14
15 static const struct io_pgtable_init_fns *
16 io_pgtable_init_table[IO_PGTABLE_NUM_FMTS] = {
17 #ifdef CONFIG_IOMMU_IO_PGTABLE_LPAE
18 [ARM_32_LPAE_S1] = &io_pgtable_arm_32_lpae_s1_init_fns,
19 [ARM_32_LPAE_S2] = &io_pgtable_arm_32_lpae_s2_init_fns,
20 [ARM_64_LPAE_S1] = &io_pgtable_arm_64_lpae_s1_init_fns,
21 [ARM_64_LPAE_S2] = &io_pgtable_arm_64_lpae_s2_init_fns,
22 [ARM_MALI_LPAE] = &io_pgtable_arm_mali_lpae_init_fns,
23 #endif
24 #ifdef CONFIG_IOMMU_IO_PGTABLE_ARMV7S
25 [ARM_V7S] = &io_pgtable_arm_v7s_init_fns,
26 #endif
27 };
28
alloc_io_pgtable_ops(enum io_pgtable_fmt fmt,struct io_pgtable_cfg * cfg,void * cookie)29 struct io_pgtable_ops *alloc_io_pgtable_ops(enum io_pgtable_fmt fmt,
30 struct io_pgtable_cfg *cfg,
31 void *cookie)
32 {
33 struct io_pgtable *iop;
34 const struct io_pgtable_init_fns *fns;
35
36 if (fmt >= IO_PGTABLE_NUM_FMTS)
37 return NULL;
38
39 fns = io_pgtable_init_table[fmt];
40 if (!fns)
41 return NULL;
42
43 iop = fns->alloc(cfg, cookie);
44 if (!iop)
45 return NULL;
46
47 iop->fmt = fmt;
48 iop->cookie = cookie;
49 iop->cfg = *cfg;
50
51 return &iop->ops;
52 }
53 EXPORT_SYMBOL_GPL(alloc_io_pgtable_ops);
54
55 /*
56 * It is the IOMMU driver's responsibility to ensure that the page table
57 * is no longer accessible to the walker by this point.
58 */
free_io_pgtable_ops(struct io_pgtable_ops * ops)59 void free_io_pgtable_ops(struct io_pgtable_ops *ops)
60 {
61 struct io_pgtable *iop;
62
63 if (!ops)
64 return;
65
66 iop = container_of(ops, struct io_pgtable, ops);
67 io_pgtable_tlb_flush_all(iop);
68 io_pgtable_init_table[iop->fmt]->free(iop);
69 }
70 EXPORT_SYMBOL_GPL(free_io_pgtable_ops);
71
io_pgtable_alloc_pages(struct io_pgtable_cfg * cfg,void * cookie,int order,gfp_t gfp_mask)72 void *io_pgtable_alloc_pages(struct io_pgtable_cfg *cfg, void *cookie,
73 int order, gfp_t gfp_mask)
74 {
75 struct device *dev;
76 struct page *p;
77
78 if (!cfg)
79 return NULL;
80
81 if (cfg->iommu_pgtable_ops && cfg->iommu_pgtable_ops->alloc_pgtable)
82 return cfg->iommu_pgtable_ops->alloc_pgtable(cookie, order,
83 gfp_mask);
84
85 dev = cfg->iommu_dev;
86 p = alloc_pages_node(dev ? dev_to_node(dev) : NUMA_NO_NODE,
87 gfp_mask, order);
88 if (!p)
89 return NULL;
90 return page_address(p);
91 }
92
io_pgtable_free_pages(struct io_pgtable_cfg * cfg,void * cookie,void * virt,int order)93 void io_pgtable_free_pages(struct io_pgtable_cfg *cfg, void *cookie, void *virt,
94 int order)
95 {
96 if (!cfg)
97 return;
98
99 if (cfg->iommu_pgtable_ops && cfg->iommu_pgtable_ops->free_pgtable)
100 cfg->iommu_pgtable_ops->free_pgtable(cookie, virt, order);
101 else
102 free_pages((unsigned long)virt, order);
103 }
104