include/linux/io-pgtable.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef __IO_PGTABLE_H
   3 #define __IO_PGTABLE_H
   4
   5 #include <linux/bitops.h>
   6 #include <linux/iommu.h>
   7
   8 /*
   9  * Public API for use by IOMMU drivers
  10  */
  11 enum io_pgtable_fmt {
  12         ARM_32_LPAE_S1,
  13         ARM_32_LPAE_S2,
  14         ARM_64_LPAE_S1,
  15         ARM_64_LPAE_S2,
  16         ARM_V7S,
  17         ARM_MALI_LPAE,
  18         AMD_IOMMU_V1,
  19         IO_PGTABLE_NUM_FMTS,
  20 };
  21
  22 /**
  23  * struct iommu_flush_ops - IOMMU callbacks for TLB and page table management.
  24  *
  25  * @tlb_flush_all:  Synchronously invalidate the entire TLB context.
  26  * @tlb_flush_walk: Synchronously invalidate all intermediate TLB state
  27  *                  (sometimes referred to as the "walk cache") for a virtual
  28  *                  address range.
  29  * @tlb_add_page:   Optional callback to queue up leaf TLB invalidation for a
  30  *                  single page.  IOMMUs that cannot batch TLB invalidation
  31  *                  operations efficiently will typically issue them here, but
  32  *                  others may decide to update the iommu_iotlb_gather structure
  33  *                  and defer the invalidation until iommu_iotlb_sync() instead.
  34  *
  35  * Note that these can all be called in atomic context and must therefore
  36  * not block.
  37  */
  38 struct iommu_flush_ops {
  39         void (*tlb_flush_all)(void *cookie);
  40         void (*tlb_flush_walk)(unsigned long iova, size_t size, size_t granule,
  41                                void *cookie);
  42         void (*tlb_add_page)(struct iommu_iotlb_gather *gather,
  43                              unsigned long iova, size_t granule, void *cookie);
  44 };
  45
  46 /**
  47  * struct io_pgtable_cfg - Configuration data for a set of page tables.
  48  *
  49  * @quirks:        A bitmap of hardware quirks that require some special
  50  *                 action by the low-level page table allocator.
  51  * @pgsize_bitmap: A bitmap of page sizes supported by this set of page
  52  *                 tables.
  53  * @ias:           Input address (iova) size, in bits.
  54  * @oas:           Output address (paddr) size, in bits.
  55  * @coherent_walk  A flag to indicate whether or not page table walks made
  56  *                 by the IOMMU are coherent with the CPU caches.
  57  * @tlb:           TLB management callbacks for this set of tables.
  58  * @iommu_dev:     The device representing the DMA configuration for the
  59  *                 page table walker.
  60  */
  61 struct io_pgtable_cfg {
  62         /*
  63          * IO_PGTABLE_QUIRK_ARM_NS: (ARM formats) Set NS and NSTABLE bits in
  64          *      stage 1 PTEs, for hardware which insists on validating them
  65          *      even in non-secure state where they should normally be ignored.
  66          *
  67          * IO_PGTABLE_QUIRK_NO_PERMS: Ignore the IOMMU_READ, IOMMU_WRITE and
  68          *      IOMMU_NOEXEC flags and map everything with full access, for
  69          *      hardware which does not implement the permissions of a given
  70          *      format, and/or requires some format-specific default value.
  71          *
  72          * IO_PGTABLE_QUIRK_ARM_MTK_EXT: (ARM v7s format) MediaTek IOMMUs extend
  73          *      to support up to 35 bits PA where the bit32, bit33 and bit34 are
  74          *      encoded in the bit9, bit4 and bit5 of the PTE respectively.
  75          *
  76          * IO_PGTABLE_QUIRK_NON_STRICT: Skip issuing synchronous leaf TLBIs
  77          *      on unmap, for DMA domains using the flush queue mechanism for
  78          *      delayed invalidation.
  79          *
  80          * IO_PGTABLE_QUIRK_ARM_TTBR1: (ARM LPAE format) Configure the table
  81          *      for use in the upper half of a split address space.
  82          *
  83          * IO_PGTABLE_QUIRK_ARM_OUTER_WBWA: Override the outer-cacheability
  84          *      attributes set in the TCR for a non-coherent page-table walker.
  85          */
  86         #define IO_PGTABLE_QUIRK_ARM_NS         BIT(0)
  87         #define IO_PGTABLE_QUIRK_NO_PERMS       BIT(1)
  88         #define IO_PGTABLE_QUIRK_ARM_MTK_EXT    BIT(3)
  89         #define IO_PGTABLE_QUIRK_NON_STRICT     BIT(4)
  90         #define IO_PGTABLE_QUIRK_ARM_TTBR1      BIT(5)
  91         #define IO_PGTABLE_QUIRK_ARM_OUTER_WBWA BIT(6)
  92         unsigned long                   quirks;
  93         unsigned long                   pgsize_bitmap;
  94         unsigned int                    ias;
  95         unsigned int                    oas;
  96         bool                            coherent_walk;
  97         const struct iommu_flush_ops    *tlb;
  98         struct device                   *iommu_dev;
  99
 100         /* Low-level data specific to the table format */
 101         union {
 102                 struct {
 103                         u64     ttbr;
 104                         struct {
 105                                 u32     ips:3;
 106                                 u32     tg:2;
 107                                 u32     sh:2;
 108                                 u32     orgn:2;
 109                                 u32     irgn:2;
 110                                 u32     tsz:6;
 111                         }       tcr;
 112                         u64     mair;
 113                 } arm_lpae_s1_cfg;
 114
 115                 struct {
 116                         u64     vttbr;
 117                         struct {
 118                                 u32     ps:3;
 119                                 u32     tg:2;
 120                                 u32     sh:2;
 121                                 u32     orgn:2;
 122                                 u32     irgn:2;
 123                                 u32     sl:2;
 124                                 u32     tsz:6;
 125                         }       vtcr;
 126                 } arm_lpae_s2_cfg;
 127
 128                 struct {
 129                         u32     ttbr;
 130                         u32     tcr;
 131                         u32     nmrr;
 132                         u32     prrr;
 133                 } arm_v7s_cfg;
 134
 135                 struct {
 136                         u64     transtab;
 137                         u64     memattr;
 138                 } arm_mali_lpae_cfg;
 139         };
 140 };
 141
 142 /**
 143  * struct io_pgtable_ops - Page table manipulation API for IOMMU drivers.
 144  *
 145  * @map:          Map a physically contiguous memory region.
 146  * @unmap:        Unmap a physically contiguous memory region.
 147  * @iova_to_phys: Translate iova to physical address.
 148  *
 149  * These functions map directly onto the iommu_ops member functions with
 150  * the same names.
 151  */
 152 struct io_pgtable_ops {
 153         int (*map)(struct io_pgtable_ops *ops, unsigned long iova,
 154                    phys_addr_t paddr, size_t size, int prot, gfp_t gfp);
 155         size_t (*unmap)(struct io_pgtable_ops *ops, unsigned long iova,
 156                         size_t size, struct iommu_iotlb_gather *gather);
 157         phys_addr_t (*iova_to_phys)(struct io_pgtable_ops *ops,
 158                                     unsigned long iova);
 159 };
 160
 161 /**
 162  * alloc_io_pgtable_ops() - Allocate a page table allocator for use by an IOMMU.
 163  *
 164  * @fmt:    The page table format.
 165  * @cfg:    The page table configuration. This will be modified to represent
 166  *          the configuration actually provided by the allocator (e.g. the
 167  *          pgsize_bitmap may be restricted).
 168  * @cookie: An opaque token provided by the IOMMU driver and passed back to
 169  *          the callback routines in cfg->tlb.
 170  */
 171 struct io_pgtable_ops *alloc_io_pgtable_ops(enum io_pgtable_fmt fmt,
 172                                             struct io_pgtable_cfg *cfg,
 173                                             void *cookie);
 174
 175 /**
 176  * free_io_pgtable_ops() - Free an io_pgtable_ops structure. The caller
 177  *                         *must* ensure that the page table is no longer
 178  *                         live, but the TLB can be dirty.
 179  *
 180  * @ops: The ops returned from alloc_io_pgtable_ops.
 181  */
 182 void free_io_pgtable_ops(struct io_pgtable_ops *ops);
 183
 184
 185 /*
 186  * Internal structures for page table allocator implementations.
 187  */
 188
 189 /**
 190  * struct io_pgtable - Internal structure describing a set of page tables.
 191  *
 192  * @fmt:    The page table format.
 193  * @cookie: An opaque token provided by the IOMMU driver and passed back to
 194  *          any callback routines.
 195  * @cfg:    A copy of the page table configuration.
 196  * @ops:    The page table operations in use for this set of page tables.
 197  */
 198 struct io_pgtable {
 199         enum io_pgtable_fmt     fmt;
 200         void                    *cookie;
 201         struct io_pgtable_cfg   cfg;
 202         struct io_pgtable_ops   ops;
 203 };
 204
 205 #define io_pgtable_ops_to_pgtable(x) container_of((x), struct io_pgtable, ops)
 206
 207 static inline void io_pgtable_tlb_flush_all(struct io_pgtable *iop)
 208 {
 209         if (iop->cfg.tlb && iop->cfg.tlb->tlb_flush_all)
 210                 iop->cfg.tlb->tlb_flush_all(iop->cookie);
 211 }
 212
 213 static inline void
 214 io_pgtable_tlb_flush_walk(struct io_pgtable *iop, unsigned long iova,
 215                           size_t size, size_t granule)
 216 {
 217         if (iop->cfg.tlb && iop->cfg.tlb->tlb_flush_walk)
 218                 iop->cfg.tlb->tlb_flush_walk(iova, size, granule, iop->cookie);
 219 }
 220
 221 static inline void
 222 io_pgtable_tlb_add_page(struct io_pgtable *iop,
 223                         struct iommu_iotlb_gather * gather, unsigned long iova,
 224                         size_t granule)
 225 {
 226         if (iop->cfg.tlb && iop->cfg.tlb->tlb_add_page)
 227                 iop->cfg.tlb->tlb_add_page(gather, iova, granule, iop->cookie);
 228 }
 229
 230 /**
 231  * struct io_pgtable_init_fns - Alloc/free a set of page tables for a
 232  *                              particular format.
 233  *
 234  * @alloc: Allocate a set of page tables described by cfg.
 235  * @free:  Free the page tables associated with iop.
 236  */
 237 struct io_pgtable_init_fns {
 238         struct io_pgtable *(*alloc)(struct io_pgtable_cfg *cfg, void *cookie);
 239         void (*free)(struct io_pgtable *iop);
 240 };
 241
 242 extern struct io_pgtable_init_fns io_pgtable_arm_32_lpae_s1_init_fns;
 243 extern struct io_pgtable_init_fns io_pgtable_arm_32_lpae_s2_init_fns;
 244 extern struct io_pgtable_init_fns io_pgtable_arm_64_lpae_s1_init_fns;
 245 extern struct io_pgtable_init_fns io_pgtable_arm_64_lpae_s2_init_fns;
 246 extern struct io_pgtable_init_fns io_pgtable_arm_v7s_init_fns;
 247 extern struct io_pgtable_init_fns io_pgtable_arm_mali_lpae_init_fns;
 248 extern struct io_pgtable_init_fns io_pgtable_amd_iommu_v1_init_fns;
 249
 250 #endif /* __IO_PGTABLE_H */