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         AMD_IOMMU_V2,
  20         APPLE_DART,
  21         APPLE_DART2,
  22         IO_PGTABLE_NUM_FMTS,
  23 };
  24
  25 /**
  26  * struct iommu_flush_ops - IOMMU callbacks for TLB and page table management.
  27  *
  28  * @tlb_flush_all:  Synchronously invalidate the entire TLB context.
  29  * @tlb_flush_walk: Synchronously invalidate all intermediate TLB state
  30  *                  (sometimes referred to as the "walk cache") for a virtual
  31  *                  address range.
  32  * @tlb_add_page:   Optional callback to queue up leaf TLB invalidation for a
  33  *                  single page.  IOMMUs that cannot batch TLB invalidation
  34  *                  operations efficiently will typically issue them here, but
  35  *                  others may decide to update the iommu_iotlb_gather structure
  36  *                  and defer the invalidation until iommu_iotlb_sync() instead.
  37  *
  38  * Note that these can all be called in atomic context and must therefore
  39  * not block.
  40  */
  41 struct iommu_flush_ops {
  42         void (*tlb_flush_all)(void *cookie);
  43         void (*tlb_flush_walk)(unsigned long iova, size_t size, size_t granule,
  44                                void *cookie);
  45         void (*tlb_add_page)(struct iommu_iotlb_gather *gather,
  46                              unsigned long iova, size_t granule, void *cookie);
  47 };
  48
  49 /**
  50  * struct io_pgtable_cfg - Configuration data for a set of page tables.
  51  *
  52  * @quirks:        A bitmap of hardware quirks that require some special
  53  *                 action by the low-level page table allocator.
  54  * @pgsize_bitmap: A bitmap of page sizes supported by this set of page
  55  *                 tables.
  56  * @ias:           Input address (iova) size, in bits.
  57  * @oas:           Output address (paddr) size, in bits.
  58  * @coherent_walk  A flag to indicate whether or not page table walks made
  59  *                 by the IOMMU are coherent with the CPU caches.
  60  * @tlb:           TLB management callbacks for this set of tables.
  61  * @iommu_dev:     The device representing the DMA configuration for the
  62  *                 page table walker.
  63  */
  64 struct io_pgtable_cfg {
  65         /*
  66          * IO_PGTABLE_QUIRK_ARM_NS: (ARM formats) Set NS and NSTABLE bits in
  67          *      stage 1 PTEs, for hardware which insists on validating them
  68          *      even in non-secure state where they should normally be ignored.
  69          *
  70          * IO_PGTABLE_QUIRK_NO_PERMS: Ignore the IOMMU_READ, IOMMU_WRITE and
  71          *      IOMMU_NOEXEC flags and map everything with full access, for
  72          *      hardware which does not implement the permissions of a given
  73          *      format, and/or requires some format-specific default value.
  74          *
  75          * IO_PGTABLE_QUIRK_ARM_MTK_EXT: (ARM v7s format) MediaTek IOMMUs extend
  76          *      to support up to 35 bits PA where the bit32, bit33 and bit34 are
  77          *      encoded in the bit9, bit4 and bit5 of the PTE respectively.
  78          *
  79          * IO_PGTABLE_QUIRK_ARM_MTK_TTBR_EXT: (ARM v7s format) MediaTek IOMMUs
  80          *      extend the translation table base support up to 35 bits PA, the
  81          *      encoding format is same with IO_PGTABLE_QUIRK_ARM_MTK_EXT.
  82          *
  83          * IO_PGTABLE_QUIRK_ARM_TTBR1: (ARM LPAE format) Configure the table
  84          *      for use in the upper half of a split address space.
  85          *
  86          * IO_PGTABLE_QUIRK_ARM_OUTER_WBWA: Override the outer-cacheability
  87          *      attributes set in the TCR for a non-coherent page-table walker.
  88          *
  89          * IO_PGTABLE_QUIRK_ARM_HD: Enables dirty tracking in stage 1 pagetable.
  90          * IO_PGTABLE_QUIRK_ARM_S2FWB: Use the FWB format for the MemAttrs bits
  91          */
  92         #define IO_PGTABLE_QUIRK_ARM_NS                 BIT(0)
  93         #define IO_PGTABLE_QUIRK_NO_PERMS               BIT(1)
  94         #define IO_PGTABLE_QUIRK_ARM_MTK_EXT            BIT(3)
  95         #define IO_PGTABLE_QUIRK_ARM_MTK_TTBR_EXT       BIT(4)
  96         #define IO_PGTABLE_QUIRK_ARM_TTBR1              BIT(5)
  97         #define IO_PGTABLE_QUIRK_ARM_OUTER_WBWA         BIT(6)
  98         #define IO_PGTABLE_QUIRK_ARM_HD                 BIT(7)
  99         #define IO_PGTABLE_QUIRK_ARM_S2FWB              BIT(8)
 100         unsigned long                   quirks;
 101         unsigned long                   pgsize_bitmap;
 102         unsigned int                    ias;
 103         unsigned int                    oas;
 104         bool                            coherent_walk;
 105         const struct iommu_flush_ops    *tlb;
 106         struct device                   *iommu_dev;
 107
 108         /**
 109          * @alloc: Custom page allocator.
 110          *
 111          * Optional hook used to allocate page tables. If this function is NULL,
 112          * @free must be NULL too.
 113          *
 114          * Memory returned should be zeroed and suitable for dma_map_single() and
 115          * virt_to_phys().
 116          *
 117          * Not all formats support custom page allocators. Before considering
 118          * passing a non-NULL value, make sure the chosen page format supports
 119          * this feature.
 120          */
 121         void *(*alloc)(void *cookie, size_t size, gfp_t gfp);
 122
 123         /**
 124          * @free: Custom page de-allocator.
 125          *
 126          * Optional hook used to free page tables allocated with the @alloc
 127          * hook. Must be non-NULL if @alloc is not NULL, must be NULL
 128          * otherwise.
 129          */
 130         void (*free)(void *cookie, void *pages, size_t size);
 131
 132         /* Low-level data specific to the table format */
 133         union {
 134                 struct {
 135                         u64     ttbr;
 136                         struct {
 137                                 u32     ips:3;
 138                                 u32     tg:2;
 139                                 u32     sh:2;
 140                                 u32     orgn:2;
 141                                 u32     irgn:2;
 142                                 u32     tsz:6;
 143                         }       tcr;
 144                         u64     mair;
 145                 } arm_lpae_s1_cfg;
 146
 147                 struct {
 148                         u64     vttbr;
 149                         struct {
 150                                 u32     ps:3;
 151                                 u32     tg:2;
 152                                 u32     sh:2;
 153                                 u32     orgn:2;
 154                                 u32     irgn:2;
 155                                 u32     sl:2;
 156                                 u32     tsz:6;
 157                         }       vtcr;
 158                 } arm_lpae_s2_cfg;
 159
 160                 struct {
 161                         u32     ttbr;
 162                         u32     tcr;
 163                         u32     nmrr;
 164                         u32     prrr;
 165                 } arm_v7s_cfg;
 166
 167                 struct {
 168                         u64     transtab;
 169                         u64     memattr;
 170                 } arm_mali_lpae_cfg;
 171
 172                 struct {
 173                         u64 ttbr[4];
 174                         u32 n_ttbrs;
 175                 } apple_dart_cfg;
 176
 177                 struct {
 178                         int nid;
 179                 } amd;
 180         };
 181 };
 182
 183 /**
 184  * struct arm_lpae_io_pgtable_walk_data - information from a pgtable walk
 185  *
 186  * @ptes:     The recorded PTE values from the walk
 187  */
 188 struct arm_lpae_io_pgtable_walk_data {
 189         u64 ptes[4];
 190 };
 191
 192 /**
 193  * struct io_pgtable_ops - Page table manipulation API for IOMMU drivers.
 194  *
 195  * @map_pages:    Map a physically contiguous range of pages of the same size.
 196  * @unmap_pages:  Unmap a range of virtually contiguous pages of the same size.
 197  * @iova_to_phys: Translate iova to physical address.
 198  * @pgtable_walk: (optional) Perform a page table walk for a given iova.
 199  *
 200  * These functions map directly onto the iommu_ops member functions with
 201  * the same names.
 202  */
 203 struct io_pgtable_ops {
 204         int (*map_pages)(struct io_pgtable_ops *ops, unsigned long iova,
 205                          phys_addr_t paddr, size_t pgsize, size_t pgcount,
 206                          int prot, gfp_t gfp, size_t *mapped);
 207         size_t (*unmap_pages)(struct io_pgtable_ops *ops, unsigned long iova,
 208                               size_t pgsize, size_t pgcount,
 209                               struct iommu_iotlb_gather *gather);
 210         phys_addr_t (*iova_to_phys)(struct io_pgtable_ops *ops,
 211                                     unsigned long iova);
 212         int (*pgtable_walk)(struct io_pgtable_ops *ops, unsigned long iova, void *wd);
 213         int (*read_and_clear_dirty)(struct io_pgtable_ops *ops,
 214                                     unsigned long iova, size_t size,
 215                                     unsigned long flags,
 216                                     struct iommu_dirty_bitmap *dirty);
 217 };
 218
 219 /**
 220  * alloc_io_pgtable_ops() - Allocate a page table allocator for use by an IOMMU.
 221  *
 222  * @fmt:    The page table format.
 223  * @cfg:    The page table configuration. This will be modified to represent
 224  *          the configuration actually provided by the allocator (e.g. the
 225  *          pgsize_bitmap may be restricted).
 226  * @cookie: An opaque token provided by the IOMMU driver and passed back to
 227  *          the callback routines in cfg->tlb.
 228  */
 229 struct io_pgtable_ops *alloc_io_pgtable_ops(enum io_pgtable_fmt fmt,
 230                                             struct io_pgtable_cfg *cfg,
 231                                             void *cookie);
 232
 233 /**
 234  * free_io_pgtable_ops() - Free an io_pgtable_ops structure. The caller
 235  *                         *must* ensure that the page table is no longer
 236  *                         live, but the TLB can be dirty.
 237  *
 238  * @ops: The ops returned from alloc_io_pgtable_ops.
 239  */
 240 void free_io_pgtable_ops(struct io_pgtable_ops *ops);
 241
 242
 243 /*
 244  * Internal structures for page table allocator implementations.
 245  */
 246
 247 /**
 248  * struct io_pgtable - Internal structure describing a set of page tables.
 249  *
 250  * @fmt:    The page table format.
 251  * @cookie: An opaque token provided by the IOMMU driver and passed back to
 252  *          any callback routines.
 253  * @cfg:    A copy of the page table configuration.
 254  * @ops:    The page table operations in use for this set of page tables.
 255  */
 256 struct io_pgtable {
 257         enum io_pgtable_fmt     fmt;
 258         void                    *cookie;
 259         struct io_pgtable_cfg   cfg;
 260         struct io_pgtable_ops   ops;
 261 };
 262
 263 #define io_pgtable_ops_to_pgtable(x) container_of((x), struct io_pgtable, ops)
 264
 265 static inline void io_pgtable_tlb_flush_all(struct io_pgtable *iop)
 266 {
 267         if (iop->cfg.tlb && iop->cfg.tlb->tlb_flush_all)
 268                 iop->cfg.tlb->tlb_flush_all(iop->cookie);
 269 }
 270
 271 static inline void
 272 io_pgtable_tlb_flush_walk(struct io_pgtable *iop, unsigned long iova,
 273                           size_t size, size_t granule)
 274 {
 275         if (iop->cfg.tlb && iop->cfg.tlb->tlb_flush_walk)
 276                 iop->cfg.tlb->tlb_flush_walk(iova, size, granule, iop->cookie);
 277 }
 278
 279 static inline void
 280 io_pgtable_tlb_add_page(struct io_pgtable *iop,
 281                         struct iommu_iotlb_gather * gather, unsigned long iova,
 282                         size_t granule)
 283 {
 284         if (iop->cfg.tlb && iop->cfg.tlb->tlb_add_page)
 285                 iop->cfg.tlb->tlb_add_page(gather, iova, granule, iop->cookie);
 286 }
 287
 288 /**
 289  * enum io_pgtable_caps - IO page table backend capabilities.
 290  */
 291 enum io_pgtable_caps {
 292         /** @IO_PGTABLE_CAP_CUSTOM_ALLOCATOR: Backend accepts custom page table allocators. */
 293         IO_PGTABLE_CAP_CUSTOM_ALLOCATOR = BIT(0),
 294 };
 295
 296 /**
 297  * struct io_pgtable_init_fns - Alloc/free a set of page tables for a
 298  *                              particular format.
 299  *
 300  * @alloc: Allocate a set of page tables described by cfg.
 301  * @free:  Free the page tables associated with iop.
 302  * @caps:  Combination of @io_pgtable_caps flags encoding the backend capabilities.
 303  */
 304 struct io_pgtable_init_fns {
 305         struct io_pgtable *(*alloc)(struct io_pgtable_cfg *cfg, void *cookie);
 306         void (*free)(struct io_pgtable *iop);
 307         u32 caps;
 308 };
 309
 310 extern struct io_pgtable_init_fns io_pgtable_arm_32_lpae_s1_init_fns;
 311 extern struct io_pgtable_init_fns io_pgtable_arm_32_lpae_s2_init_fns;
 312 extern struct io_pgtable_init_fns io_pgtable_arm_64_lpae_s1_init_fns;
 313 extern struct io_pgtable_init_fns io_pgtable_arm_64_lpae_s2_init_fns;
 314 extern struct io_pgtable_init_fns io_pgtable_arm_v7s_init_fns;
 315 extern struct io_pgtable_init_fns io_pgtable_arm_mali_lpae_init_fns;
 316 extern struct io_pgtable_init_fns io_pgtable_amd_iommu_v1_init_fns;
 317 extern struct io_pgtable_init_fns io_pgtable_amd_iommu_v2_init_fns;
 318 extern struct io_pgtable_init_fns io_pgtable_apple_dart_init_fns;
 319
 320 #endif /* __IO_PGTABLE_H */