include/linux/tee_drv.h

   1 /*
   2  * Copyright (c) 2015-2016, Linaro Limited
   3  *
   4  * This software is licensed under the terms of the GNU General Public
   5  * License version 2, as published by the Free Software Foundation, and
   6  * may be copied, distributed, and modified under those terms.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  */
  14
  15 #ifndef __TEE_DRV_H
  16 #define __TEE_DRV_H
  17
  18 #include <linux/types.h>
  19 #include <linux/idr.h>
  20 #include <linux/list.h>
  21 #include <linux/tee.h>
  22
  23 /*
  24  * The file describes the API provided by the generic TEE driver to the
  25  * specific TEE driver.
  26  */
  27
  28 #define TEE_SHM_MAPPED          0x1     /* Memory mapped by the kernel */
  29 #define TEE_SHM_DMA_BUF         0x2     /* Memory with dma-buf handle */
  30
  31 struct tee_device;
  32 struct tee_shm;
  33 struct tee_shm_pool;
  34
  35 /**
  36  * struct tee_context - driver specific context on file pointer data
  37  * @teedev:     pointer to this drivers struct tee_device
  38  * @list_shm:   List of shared memory object owned by this context
  39  * @data:       driver specific context data, managed by the driver
  40  */
  41 struct tee_context {
  42         struct tee_device *teedev;
  43         struct list_head list_shm;
  44         void *data;
  45 };
  46
  47 struct tee_param_memref {
  48         size_t shm_offs;
  49         size_t size;
  50         struct tee_shm *shm;
  51 };
  52
  53 struct tee_param_value {
  54         u64 a;
  55         u64 b;
  56         u64 c;
  57 };
  58
  59 struct tee_param {
  60         u64 attr;
  61         union {
  62                 struct tee_param_memref memref;
  63                 struct tee_param_value value;
  64         } u;
  65 };
  66
  67 /**
  68  * struct tee_driver_ops - driver operations vtable
  69  * @get_version:        returns version of driver
  70  * @open:               called when the device file is opened
  71  * @release:            release this open file
  72  * @open_session:       open a new session
  73  * @close_session:      close a session
  74  * @invoke_func:        invoke a trusted function
  75  * @cancel_req:         request cancel of an ongoing invoke or open
  76  * @supp_revc:          called for supplicant to get a command
  77  * @supp_send:          called for supplicant to send a response
  78  */
  79 struct tee_driver_ops {
  80         void (*get_version)(struct tee_device *teedev,
  81                             struct tee_ioctl_version_data *vers);
  82         int (*open)(struct tee_context *ctx);
  83         void (*release)(struct tee_context *ctx);
  84         int (*open_session)(struct tee_context *ctx,
  85                             struct tee_ioctl_open_session_arg *arg,
  86                             struct tee_param *param);
  87         int (*close_session)(struct tee_context *ctx, u32 session);
  88         int (*invoke_func)(struct tee_context *ctx,
  89                            struct tee_ioctl_invoke_arg *arg,
  90                            struct tee_param *param);
  91         int (*cancel_req)(struct tee_context *ctx, u32 cancel_id, u32 session);
  92         int (*supp_recv)(struct tee_context *ctx, u32 *func, u32 *num_params,
  93                          struct tee_param *param);
  94         int (*supp_send)(struct tee_context *ctx, u32 ret, u32 num_params,
  95                          struct tee_param *param);
  96 };
  97
  98 /**
  99  * struct tee_desc - Describes the TEE driver to the subsystem
 100  * @name:       name of driver
 101  * @ops:        driver operations vtable
 102  * @owner:      module providing the driver
 103  * @flags:      Extra properties of driver, defined by TEE_DESC_* below
 104  */
 105 #define TEE_DESC_PRIVILEGED     0x1
 106 struct tee_desc {
 107         const char *name;
 108         const struct tee_driver_ops *ops;
 109         struct module *owner;
 110         u32 flags;
 111 };
 112
 113 /**
 114  * tee_device_alloc() - Allocate a new struct tee_device instance
 115  * @teedesc:    Descriptor for this driver
 116  * @dev:        Parent device for this device
 117  * @pool:       Shared memory pool, NULL if not used
 118  * @driver_data: Private driver data for this device
 119  *
 120  * Allocates a new struct tee_device instance. The device is
 121  * removed by tee_device_unregister().
 122  *
 123  * @returns a pointer to a 'struct tee_device' or an ERR_PTR on failure
 124  */
 125 struct tee_device *tee_device_alloc(const struct tee_desc *teedesc,
 126                                     struct device *dev,
 127                                     struct tee_shm_pool *pool,
 128                                     void *driver_data);
 129
 130 /**
 131  * tee_device_register() - Registers a TEE device
 132  * @teedev:     Device to register
 133  *
 134  * tee_device_unregister() need to be called to remove the @teedev if
 135  * this function fails.
 136  *
 137  * @returns < 0 on failure
 138  */
 139 int tee_device_register(struct tee_device *teedev);
 140
 141 /**
 142  * tee_device_unregister() - Removes a TEE device
 143  * @teedev:     Device to unregister
 144  *
 145  * This function should be called to remove the @teedev even if
 146  * tee_device_register() hasn't been called yet. Does nothing if
 147  * @teedev is NULL.
 148  */
 149 void tee_device_unregister(struct tee_device *teedev);
 150
 151 /**
 152  * struct tee_shm_pool_mem_info - holds information needed to create a shared
 153  * memory pool
 154  * @vaddr:      Virtual address of start of pool
 155  * @paddr:      Physical address of start of pool
 156  * @size:       Size in bytes of the pool
 157  */
 158 struct tee_shm_pool_mem_info {
 159         unsigned long vaddr;
 160         phys_addr_t paddr;
 161         size_t size;
 162 };
 163
 164 /**
 165  * tee_shm_pool_alloc_res_mem() - Create a shared memory pool from reserved
 166  * memory range
 167  * @priv_info:   Information for driver private shared memory pool
 168  * @dmabuf_info: Information for dma-buf shared memory pool
 169  *
 170  * Start and end of pools will must be page aligned.
 171  *
 172  * Allocation with the flag TEE_SHM_DMA_BUF set will use the range supplied
 173  * in @dmabuf, others will use the range provided by @priv.
 174  *
 175  * @returns pointer to a 'struct tee_shm_pool' or an ERR_PTR on failure.
 176  */
 177 struct tee_shm_pool *
 178 tee_shm_pool_alloc_res_mem(struct tee_shm_pool_mem_info *priv_info,
 179                            struct tee_shm_pool_mem_info *dmabuf_info);
 180
 181 /**
 182  * tee_shm_pool_free() - Free a shared memory pool
 183  * @pool:       The shared memory pool to free
 184  *
 185  * The must be no remaining shared memory allocated from this pool when
 186  * this function is called.
 187  */
 188 void tee_shm_pool_free(struct tee_shm_pool *pool);
 189
 190 /**
 191  * tee_get_drvdata() - Return driver_data pointer
 192  * @returns the driver_data pointer supplied to tee_register().
 193  */
 194 void *tee_get_drvdata(struct tee_device *teedev);
 195
 196 /**
 197  * tee_shm_alloc() - Allocate shared memory
 198  * @ctx:        Context that allocates the shared memory
 199  * @size:       Requested size of shared memory
 200  * @flags:      Flags setting properties for the requested shared memory.
 201  *
 202  * Memory allocated as global shared memory is automatically freed when the
 203  * TEE file pointer is closed. The @flags field uses the bits defined by
 204  * TEE_SHM_* above. TEE_SHM_MAPPED must currently always be set. If
 205  * TEE_SHM_DMA_BUF global shared memory will be allocated and associated
 206  * with a dma-buf handle, else driver private memory.
 207  *
 208  * @returns a pointer to 'struct tee_shm'
 209  */
 210 struct tee_shm *tee_shm_alloc(struct tee_context *ctx, size_t size, u32 flags);
 211
 212 /**
 213  * tee_shm_free() - Free shared memory
 214  * @shm:        Handle to shared memory to free
 215  */
 216 void tee_shm_free(struct tee_shm *shm);
 217
 218 /**
 219  * tee_shm_put() - Decrease reference count on a shared memory handle
 220  * @shm:        Shared memory handle
 221  */
 222 void tee_shm_put(struct tee_shm *shm);
 223
 224 /**
 225  * tee_shm_va2pa() - Get physical address of a virtual address
 226  * @shm:        Shared memory handle
 227  * @va:         Virtual address to tranlsate
 228  * @pa:         Returned physical address
 229  * @returns 0 on success and < 0 on failure
 230  */
 231 int tee_shm_va2pa(struct tee_shm *shm, void *va, phys_addr_t *pa);
 232
 233 /**
 234  * tee_shm_pa2va() - Get virtual address of a physical address
 235  * @shm:        Shared memory handle
 236  * @pa:         Physical address to tranlsate
 237  * @va:         Returned virtual address
 238  * @returns 0 on success and < 0 on failure
 239  */
 240 int tee_shm_pa2va(struct tee_shm *shm, phys_addr_t pa, void **va);
 241
 242 /**
 243  * tee_shm_get_va() - Get virtual address of a shared memory plus an offset
 244  * @shm:        Shared memory handle
 245  * @offs:       Offset from start of this shared memory
 246  * @returns virtual address of the shared memory + offs if offs is within
 247  *      the bounds of this shared memory, else an ERR_PTR
 248  */
 249 void *tee_shm_get_va(struct tee_shm *shm, size_t offs);
 250
 251 /**
 252  * tee_shm_get_pa() - Get physical address of a shared memory plus an offset
 253  * @shm:        Shared memory handle
 254  * @offs:       Offset from start of this shared memory
 255  * @pa:         Physical address to return
 256  * @returns 0 if offs is within the bounds of this shared memory, else an
 257  *      error code.
 258  */
 259 int tee_shm_get_pa(struct tee_shm *shm, size_t offs, phys_addr_t *pa);
 260
 261 /**
 262  * tee_shm_get_id() - Get id of a shared memory object
 263  * @shm:        Shared memory handle
 264  * @returns id
 265  */
 266 int tee_shm_get_id(struct tee_shm *shm);
 267
 268 /**
 269  * tee_shm_get_from_id() - Find shared memory object and increase reference
 270  * count
 271  * @ctx:        Context owning the shared memory
 272  * @id:         Id of shared memory object
 273  * @returns a pointer to 'struct tee_shm' on success or an ERR_PTR on failure
 274  */
 275 struct tee_shm *tee_shm_get_from_id(struct tee_context *ctx, int id);
 276
 277 #endif /*__TEE_DRV_H*/