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_DART |
25 | [APPLE_DART] = &io_pgtable_apple_dart_init_fns, |
26 | [APPLE_DART2] = &io_pgtable_apple_dart_init_fns, |
27 | #endif |
28 | #ifdef CONFIG_IOMMU_IO_PGTABLE_ARMV7S |
29 | [ARM_V7S] = &io_pgtable_arm_v7s_init_fns, |
30 | #endif |
31 | #ifdef CONFIG_AMD_IOMMU |
32 | [AMD_IOMMU_V1] = &io_pgtable_amd_iommu_v1_init_fns, |
33 | [AMD_IOMMU_V2] = &io_pgtable_amd_iommu_v2_init_fns, |
34 | #endif |
35 | }; |
36 | |
37 | static int check_custom_allocator(enum io_pgtable_fmt fmt, |
38 | struct io_pgtable_cfg *cfg) |
39 | { |
40 | /* No custom allocator, no need to check the format. */ |
41 | if (!cfg->alloc && !cfg->free) |
42 | return 0; |
43 | |
44 | /* When passing a custom allocator, both the alloc and free |
45 | * functions should be provided. |
46 | */ |
47 | if (!cfg->alloc || !cfg->free) |
48 | return -EINVAL; |
49 | |
50 | /* Make sure the format supports custom allocators. */ |
51 | if (io_pgtable_init_table[fmt]->caps & IO_PGTABLE_CAP_CUSTOM_ALLOCATOR) |
52 | return 0; |
53 | |
54 | return -EINVAL; |
55 | } |
56 | |
57 | struct io_pgtable_ops *alloc_io_pgtable_ops(enum io_pgtable_fmt fmt, |
58 | struct io_pgtable_cfg *cfg, |
59 | void *cookie) |
60 | { |
61 | struct io_pgtable *iop; |
62 | const struct io_pgtable_init_fns *fns; |
63 | |
64 | if (fmt >= IO_PGTABLE_NUM_FMTS) |
65 | return NULL; |
66 | |
67 | if (check_custom_allocator(fmt, cfg)) |
68 | return NULL; |
69 | |
70 | fns = io_pgtable_init_table[fmt]; |
71 | if (!fns) |
72 | return NULL; |
73 | |
74 | iop = fns->alloc(cfg, cookie); |
75 | if (!iop) |
76 | return NULL; |
77 | |
78 | iop->fmt = fmt; |
79 | iop->cookie = cookie; |
80 | iop->cfg = *cfg; |
81 | |
82 | return &iop->ops; |
83 | } |
84 | EXPORT_SYMBOL_GPL(alloc_io_pgtable_ops); |
85 | |
86 | /* |
87 | * It is the IOMMU driver's responsibility to ensure that the page table |
88 | * is no longer accessible to the walker by this point. |
89 | */ |
90 | void free_io_pgtable_ops(struct io_pgtable_ops *ops) |
91 | { |
92 | struct io_pgtable *iop; |
93 | |
94 | if (!ops) |
95 | return; |
96 | |
97 | iop = io_pgtable_ops_to_pgtable(ops); |
98 | io_pgtable_tlb_flush_all(iop); |
99 | io_pgtable_init_table[iop->fmt]->free(iop); |
100 | } |
101 | EXPORT_SYMBOL_GPL(free_io_pgtable_ops); |
102 | |