drivers/iommu/io-pgtable.h

   1 #ifndef __IO_PGTABLE_H
   2 #define __IO_PGTABLE_H
   3
   4 /*
   5  * Public API for use by IOMMU drivers
   6  */
   7 enum io_pgtable_fmt {
   8         ARM_32_LPAE_S1,
   9         ARM_32_LPAE_S2,
  10         ARM_64_LPAE_S1,
  11         ARM_64_LPAE_S2,
  12         IO_PGTABLE_NUM_FMTS,
  13 };
  14
  15 /**
  16  * struct iommu_gather_ops - IOMMU callbacks for TLB and page table management.
  17  *
  18  * @tlb_flush_all: Synchronously invalidate the entire TLB context.
  19  * @tlb_add_flush: Queue up a TLB invalidation for a virtual address range.
  20  * @tlb_sync:      Ensure any queued TLB invalidation has taken effect, and
  21  *                 any corresponding page table updates are visible to the
  22  *                 IOMMU.
  23  *
  24  * Note that these can all be called in atomic context and must therefore
  25  * not block.
  26  */
  27 struct iommu_gather_ops {
  28         void (*tlb_flush_all)(void *cookie);
  29         void (*tlb_add_flush)(unsigned long iova, size_t size, bool leaf,
  30                               void *cookie);
  31         void (*tlb_sync)(void *cookie);
  32 };
  33
  34 /**
  35  * struct io_pgtable_cfg - Configuration data for a set of page tables.
  36  *
  37  * @quirks:        A bitmap of hardware quirks that require some special
  38  *                 action by the low-level page table allocator.
  39  * @pgsize_bitmap: A bitmap of page sizes supported by this set of page
  40  *                 tables.
  41  * @ias:           Input address (iova) size, in bits.
  42  * @oas:           Output address (paddr) size, in bits.
  43  * @tlb:           TLB management callbacks for this set of tables.
  44  * @iommu_dev:     The device representing the DMA configuration for the
  45  *                 page table walker.
  46  */
  47 struct io_pgtable_cfg {
  48         #define IO_PGTABLE_QUIRK_ARM_NS (1 << 0)        /* Set NS bit in PTEs */
  49         int                             quirks;
  50         unsigned long                   pgsize_bitmap;
  51         unsigned int                    ias;
  52         unsigned int                    oas;
  53         const struct iommu_gather_ops   *tlb;
  54         struct device                   *iommu_dev;
  55
  56         /* Low-level data specific to the table format */
  57         union {
  58                 struct {
  59                         u64     ttbr[2];
  60                         u64     tcr;
  61                         u64     mair[2];
  62                 } arm_lpae_s1_cfg;
  63
  64                 struct {
  65                         u64     vttbr;
  66                         u64     vtcr;
  67                 } arm_lpae_s2_cfg;
  68         };
  69 };
  70
  71 /**
  72  * struct io_pgtable_ops - Page table manipulation API for IOMMU drivers.
  73  *
  74  * @map:          Map a physically contiguous memory region.
  75  * @unmap:        Unmap a physically contiguous memory region.
  76  * @iova_to_phys: Translate iova to physical address.
  77  *
  78  * These functions map directly onto the iommu_ops member functions with
  79  * the same names.
  80  */
  81 struct io_pgtable_ops {
  82         int (*map)(struct io_pgtable_ops *ops, unsigned long iova,
  83                    phys_addr_t paddr, size_t size, int prot);
  84         int (*unmap)(struct io_pgtable_ops *ops, unsigned long iova,
  85                      size_t size);
  86         phys_addr_t (*iova_to_phys)(struct io_pgtable_ops *ops,
  87                                     unsigned long iova);
  88 };
  89
  90 /**
  91  * alloc_io_pgtable_ops() - Allocate a page table allocator for use by an IOMMU.
  92  *
  93  * @fmt:    The page table format.
  94  * @cfg:    The page table configuration. This will be modified to represent
  95  *          the configuration actually provided by the allocator (e.g. the
  96  *          pgsize_bitmap may be restricted).
  97  * @cookie: An opaque token provided by the IOMMU driver and passed back to
  98  *          the callback routines in cfg->tlb.
  99  */
 100 struct io_pgtable_ops *alloc_io_pgtable_ops(enum io_pgtable_fmt fmt,
 101                                             struct io_pgtable_cfg *cfg,
 102                                             void *cookie);
 103
 104 /**
 105  * free_io_pgtable_ops() - Free an io_pgtable_ops structure. The caller
 106  *                         *must* ensure that the page table is no longer
 107  *                         live, but the TLB can be dirty.
 108  *
 109  * @ops: The ops returned from alloc_io_pgtable_ops.
 110  */
 111 void free_io_pgtable_ops(struct io_pgtable_ops *ops);
 112
 113
 114 /*
 115  * Internal structures for page table allocator implementations.
 116  */
 117
 118 /**
 119  * struct io_pgtable - Internal structure describing a set of page tables.
 120  *
 121  * @fmt:    The page table format.
 122  * @cookie: An opaque token provided by the IOMMU driver and passed back to
 123  *          any callback routines.
 124  * @cfg:    A copy of the page table configuration.
 125  * @ops:    The page table operations in use for this set of page tables.
 126  */
 127 struct io_pgtable {
 128         enum io_pgtable_fmt     fmt;
 129         void                    *cookie;
 130         struct io_pgtable_cfg   cfg;
 131         struct io_pgtable_ops   ops;
 132 };
 133
 134 /**
 135  * struct io_pgtable_init_fns - Alloc/free a set of page tables for a
 136  *                              particular format.
 137  *
 138  * @alloc: Allocate a set of page tables described by cfg.
 139  * @free:  Free the page tables associated with iop.
 140  */
 141 struct io_pgtable_init_fns {
 142         struct io_pgtable *(*alloc)(struct io_pgtable_cfg *cfg, void *cookie);
 143         void (*free)(struct io_pgtable *iop);
 144 };
 145
 146 extern struct io_pgtable_init_fns io_pgtable_arm_32_lpae_s1_init_fns;
 147 extern struct io_pgtable_init_fns io_pgtable_arm_32_lpae_s2_init_fns;
 148 extern struct io_pgtable_init_fns io_pgtable_arm_64_lpae_s1_init_fns;
 149 extern struct io_pgtable_init_fns io_pgtable_arm_64_lpae_s2_init_fns;
 150
 151 #endif /* __IO_PGTABLE_H */