drivers/iommu/io-pgtable.c

   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 struct io_pgtable_ops *alloc_io_pgtable_ops(enum io_pgtable_fmt fmt,
  38                                             struct io_pgtable_cfg *cfg,
  39                                             void *cookie)
  40 {
  41         struct io_pgtable *iop;
  42         const struct io_pgtable_init_fns *fns;
  43
  44         if (fmt >= IO_PGTABLE_NUM_FMTS)
  45                 return NULL;
  46
  47         fns = io_pgtable_init_table[fmt];
  48         if (!fns)
  49                 return NULL;
  50
  51         iop = fns->alloc(cfg, cookie);
  52         if (!iop)
  53                 return NULL;
  54
  55         iop->fmt        = fmt;
  56         iop->cookie     = cookie;
  57         iop->cfg        = *cfg;
  58
  59         return &iop->ops;
  60 }
  61 EXPORT_SYMBOL_GPL(alloc_io_pgtable_ops);
  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  */
  67 void free_io_pgtable_ops(struct io_pgtable_ops *ops)
  68 {
  69         struct io_pgtable *iop;
  70
  71         if (!ops)
  72                 return;
  73
  74         iop = io_pgtable_ops_to_pgtable(ops);
  75         io_pgtable_tlb_flush_all(iop);
  76         io_pgtable_init_table[iop->fmt]->free(iop);
  77 }
  78 EXPORT_SYMBOL_GPL(free_io_pgtable_ops);