lib/efi_loader/efi_disk.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  *  EFI application disk support
   4  *
   5  *  Copyright (c) 2016 Alexander Graf
   6  */
   7
   8 #include <common.h>
   9 #include <blk.h>
  10 #include <dm.h>
  11 #include <efi_loader.h>
  12 #include <part.h>
  13 #include <malloc.h>
  14
  15 const efi_guid_t efi_block_io_guid = BLOCK_IO_GUID;
  16
  17 struct efi_disk_obj {
  18         /* Generic EFI object parent class data */
  19         struct efi_object parent;
  20         /* EFI Interface callback struct for block I/O */
  21         struct efi_block_io ops;
  22         /* U-Boot ifname for block device */
  23         const char *ifname;
  24         /* U-Boot dev_index for block device */
  25         int dev_index;
  26         /* EFI Interface Media descriptor struct, referenced by ops */
  27         struct efi_block_io_media media;
  28         /* EFI device path to this block device */
  29         struct efi_device_path *dp;
  30         /* partition # */
  31         unsigned int part;
  32         /* handle to filesys proto (for partition objects) */
  33         struct efi_simple_file_system_protocol *volume;
  34         /* Offset into disk for simple partitions */
  35         lbaint_t offset;
  36         /* Internal block device */
  37         struct blk_desc *desc;
  38 };
  39
  40 static efi_status_t EFIAPI efi_disk_reset(struct efi_block_io *this,
  41                         char extended_verification)
  42 {
  43         EFI_ENTRY("%p, %x", this, extended_verification);
  44         return EFI_EXIT(EFI_DEVICE_ERROR);
  45 }
  46
  47 enum efi_disk_direction {
  48         EFI_DISK_READ,
  49         EFI_DISK_WRITE,
  50 };
  51
  52 static efi_status_t efi_disk_rw_blocks(struct efi_block_io *this,
  53                         u32 media_id, u64 lba, unsigned long buffer_size,
  54                         void *buffer, enum efi_disk_direction direction)
  55 {
  56         struct efi_disk_obj *diskobj;
  57         struct blk_desc *desc;
  58         int blksz;
  59         int blocks;
  60         unsigned long n;
  61
  62         diskobj = container_of(this, struct efi_disk_obj, ops);
  63         desc = (struct blk_desc *) diskobj->desc;
  64         blksz = desc->blksz;
  65         blocks = buffer_size / blksz;
  66         lba += diskobj->offset;
  67
  68         debug("EFI: %s:%d blocks=%x lba=%llx blksz=%x dir=%d\n", __func__,
  69               __LINE__, blocks, lba, blksz, direction);
  70
  71         /* We only support full block access */
  72         if (buffer_size & (blksz - 1))
  73                 return EFI_DEVICE_ERROR;
  74
  75         if (direction == EFI_DISK_READ)
  76                 n = blk_dread(desc, lba, blocks, buffer);
  77         else
  78                 n = blk_dwrite(desc, lba, blocks, buffer);
  79
  80         /* We don't do interrupts, so check for timers cooperatively */
  81         efi_timer_check();
  82
  83         debug("EFI: %s:%d n=%lx blocks=%x\n", __func__, __LINE__, n, blocks);
  84
  85         if (n != blocks)
  86                 return EFI_DEVICE_ERROR;
  87
  88         return EFI_SUCCESS;
  89 }
  90
  91 static efi_status_t EFIAPI efi_disk_read_blocks(struct efi_block_io *this,
  92                         u32 media_id, u64 lba, efi_uintn_t buffer_size,
  93                         void *buffer)
  94 {
  95         void *real_buffer = buffer;
  96         efi_status_t r;
  97
  98 #ifdef CONFIG_EFI_LOADER_BOUNCE_BUFFER
  99         if (buffer_size > EFI_LOADER_BOUNCE_BUFFER_SIZE) {
 100                 r = efi_disk_read_blocks(this, media_id, lba,
 101                         EFI_LOADER_BOUNCE_BUFFER_SIZE, buffer);
 102                 if (r != EFI_SUCCESS)
 103                         return r;
 104                 return efi_disk_read_blocks(this, media_id, lba +
 105                         EFI_LOADER_BOUNCE_BUFFER_SIZE / this->media->block_size,
 106                         buffer_size - EFI_LOADER_BOUNCE_BUFFER_SIZE,
 107                         buffer + EFI_LOADER_BOUNCE_BUFFER_SIZE);
 108         }
 109
 110         real_buffer = efi_bounce_buffer;
 111 #endif
 112
 113         EFI_ENTRY("%p, %x, %llx, %zx, %p", this, media_id, lba,
 114                   buffer_size, buffer);
 115
 116         r = efi_disk_rw_blocks(this, media_id, lba, buffer_size, real_buffer,
 117                                EFI_DISK_READ);
 118
 119         /* Copy from bounce buffer to real buffer if necessary */
 120         if ((r == EFI_SUCCESS) && (real_buffer != buffer))
 121                 memcpy(buffer, real_buffer, buffer_size);
 122
 123         return EFI_EXIT(r);
 124 }
 125
 126 static efi_status_t EFIAPI efi_disk_write_blocks(struct efi_block_io *this,
 127                         u32 media_id, u64 lba, efi_uintn_t buffer_size,
 128                         void *buffer)
 129 {
 130         void *real_buffer = buffer;
 131         efi_status_t r;
 132
 133 #ifdef CONFIG_EFI_LOADER_BOUNCE_BUFFER
 134         if (buffer_size > EFI_LOADER_BOUNCE_BUFFER_SIZE) {
 135                 r = efi_disk_write_blocks(this, media_id, lba,
 136                         EFI_LOADER_BOUNCE_BUFFER_SIZE, buffer);
 137                 if (r != EFI_SUCCESS)
 138                         return r;
 139                 return efi_disk_write_blocks(this, media_id, lba +
 140                         EFI_LOADER_BOUNCE_BUFFER_SIZE / this->media->block_size,
 141                         buffer_size - EFI_LOADER_BOUNCE_BUFFER_SIZE,
 142                         buffer + EFI_LOADER_BOUNCE_BUFFER_SIZE);
 143         }
 144
 145         real_buffer = efi_bounce_buffer;
 146 #endif
 147
 148         EFI_ENTRY("%p, %x, %llx, %zx, %p", this, media_id, lba,
 149                   buffer_size, buffer);
 150
 151         /* Populate bounce buffer if necessary */
 152         if (real_buffer != buffer)
 153                 memcpy(real_buffer, buffer, buffer_size);
 154
 155         r = efi_disk_rw_blocks(this, media_id, lba, buffer_size, real_buffer,
 156                                EFI_DISK_WRITE);
 157
 158         return EFI_EXIT(r);
 159 }
 160
 161 static efi_status_t EFIAPI efi_disk_flush_blocks(struct efi_block_io *this)
 162 {
 163         /* We always write synchronously */
 164         EFI_ENTRY("%p", this);
 165         return EFI_EXIT(EFI_SUCCESS);
 166 }
 167
 168 static const struct efi_block_io block_io_disk_template = {
 169         .reset = &efi_disk_reset,
 170         .read_blocks = &efi_disk_read_blocks,
 171         .write_blocks = &efi_disk_write_blocks,
 172         .flush_blocks = &efi_disk_flush_blocks,
 173 };
 174
 175 /*
 176  * Get the simple file system protocol for a file device path.
 177  *
 178  * The full path provided is split into device part and into a file
 179  * part. The device part is used to find the handle on which the
 180  * simple file system protocol is installed.
 181  *
 182  * @full_path   device path including device and file
 183  * @return      simple file system protocol
 184  */
 185 struct efi_simple_file_system_protocol *
 186 efi_fs_from_path(struct efi_device_path *full_path)
 187 {
 188         struct efi_object *efiobj;
 189         struct efi_handler *handler;
 190         struct efi_device_path *device_path;
 191         struct efi_device_path *file_path;
 192         efi_status_t ret;
 193
 194         /* Split the path into a device part and a file part */
 195         ret = efi_dp_split_file_path(full_path, &device_path, &file_path);
 196         if (ret != EFI_SUCCESS)
 197                 return NULL;
 198         efi_free_pool(file_path);
 199
 200         /* Get the EFI object for the partition */
 201         efiobj = efi_dp_find_obj(device_path, NULL);
 202         efi_free_pool(device_path);
 203         if (!efiobj)
 204                 return NULL;
 205
 206         /* Find the simple file system protocol */
 207         ret = efi_search_protocol(efiobj, &efi_simple_file_system_protocol_guid,
 208                                   &handler);
 209         if (ret != EFI_SUCCESS)
 210                 return NULL;
 211
 212         /* Return the simple file system protocol for the partition */
 213         return handler->protocol_interface;
 214 }
 215
 216 /*
 217  * Create a handle for a partition or disk
 218  *
 219  * @parent      parent handle
 220  * @dp_parent   parent device path
 221  * @if_typename interface name for block device
 222  * @desc        internal block device
 223  * @dev_index   device index for block device
 224  * @offset      offset into disk for simple partitions
 225  * @return      disk object
 226  */
 227 static efi_status_t efi_disk_add_dev(
 228                                 efi_handle_t parent,
 229                                 struct efi_device_path *dp_parent,
 230                                 const char *if_typename,
 231                                 struct blk_desc *desc,
 232                                 int dev_index,
 233                                 lbaint_t offset,
 234                                 unsigned int part,
 235                                 struct efi_disk_obj **disk)
 236 {
 237         struct efi_disk_obj *diskobj;
 238         efi_status_t ret;
 239
 240         /* Don't add empty devices */
 241         if (!desc->lba)
 242                 return EFI_NOT_READY;
 243
 244         diskobj = calloc(1, sizeof(*diskobj));
 245         if (!diskobj)
 246                 return EFI_OUT_OF_RESOURCES;
 247
 248         /* Hook up to the device list */
 249         efi_add_handle(&diskobj->parent);
 250
 251         /* Fill in object data */
 252         if (part) {
 253                 struct efi_device_path *node = efi_dp_part_node(desc, part);
 254
 255                 diskobj->dp = efi_dp_append_node(dp_parent, node);
 256                 efi_free_pool(node);
 257         } else {
 258                 diskobj->dp = efi_dp_from_part(desc, part);
 259         }
 260         diskobj->part = part;
 261         ret = efi_add_protocol(diskobj->parent.handle, &efi_block_io_guid,
 262                                &diskobj->ops);
 263         if (ret != EFI_SUCCESS)
 264                 return ret;
 265         ret = efi_add_protocol(diskobj->parent.handle, &efi_guid_device_path,
 266                                diskobj->dp);
 267         if (ret != EFI_SUCCESS)
 268                 return ret;
 269         if (part >= 1) {
 270                 diskobj->volume = efi_simple_file_system(desc, part,
 271                                                          diskobj->dp);
 272                 ret = efi_add_protocol(diskobj->parent.handle,
 273                                        &efi_simple_file_system_protocol_guid,
 274                                        diskobj->volume);
 275                 if (ret != EFI_SUCCESS)
 276                         return ret;
 277         }
 278         diskobj->ops = block_io_disk_template;
 279         diskobj->ifname = if_typename;
 280         diskobj->dev_index = dev_index;
 281         diskobj->offset = offset;
 282         diskobj->desc = desc;
 283
 284         /* Fill in EFI IO Media info (for read/write callbacks) */
 285         diskobj->media.removable_media = desc->removable;
 286         diskobj->media.media_present = 1;
 287         diskobj->media.block_size = desc->blksz;
 288         diskobj->media.io_align = desc->blksz;
 289         diskobj->media.last_block = desc->lba - offset;
 290         if (part != 0)
 291                 diskobj->media.logical_partition = 1;
 292         diskobj->ops.media = &diskobj->media;
 293         if (disk)
 294                 *disk = diskobj;
 295         return EFI_SUCCESS;
 296 }
 297
 298 /*
 299  * Create handles and protocols for the partitions of a block device
 300  *
 301  * @parent              handle of the parent disk
 302  * @blk_desc            block device
 303  * @if_typename         interface type
 304  * @diskid              device number
 305  * @pdevname            device name
 306  * @return              number of partitions created
 307  */
 308 int efi_disk_create_partitions(efi_handle_t parent, struct blk_desc *desc,
 309                                const char *if_typename, int diskid,
 310                                const char *pdevname)
 311 {
 312         int disks = 0;
 313         char devname[32] = { 0 }; /* dp->str is u16[32] long */
 314         disk_partition_t info;
 315         int part;
 316         struct efi_device_path *dp = NULL;
 317         efi_status_t ret;
 318         struct efi_handler *handler;
 319
 320         /* Get the device path of the parent */
 321         ret = efi_search_protocol(parent, &efi_guid_device_path, &handler);
 322         if (ret == EFI_SUCCESS)
 323                 dp = handler->protocol_interface;
 324
 325         /* Add devices for each partition */
 326         for (part = 1; part <= MAX_SEARCH_PARTITIONS; part++) {
 327                 if (part_get_info(desc, part, &info))
 328                         continue;
 329                 snprintf(devname, sizeof(devname), "%s:%d", pdevname,
 330                          part);
 331                 ret = efi_disk_add_dev(parent, dp, if_typename, desc, diskid,
 332                                        info.start, part, NULL);
 333                 if (ret != EFI_SUCCESS) {
 334                         printf("Adding partition %s failed\n", pdevname);
 335                         continue;
 336                 }
 337                 disks++;
 338         }
 339
 340         return disks;
 341 }
 342
 343 /*
 344  * U-Boot doesn't have a list of all online disk devices. So when running our
 345  * EFI payload, we scan through all of the potentially available ones and
 346  * store them in our object pool.
 347  *
 348  * TODO(sjg@chromium.org): Actually with CONFIG_BLK, U-Boot does have this.
 349  * Consider converting the code to look up devices as needed. The EFI device
 350  * could be a child of the UCLASS_BLK block device, perhaps.
 351  *
 352  * This gets called from do_bootefi_exec().
 353  */
 354 efi_status_t efi_disk_register(void)
 355 {
 356         struct efi_disk_obj *disk;
 357         int disks = 0;
 358         efi_status_t ret;
 359 #ifdef CONFIG_BLK
 360         struct udevice *dev;
 361
 362         for (uclass_first_device_check(UCLASS_BLK, &dev); dev;
 363              uclass_next_device_check(&dev)) {
 364                 struct blk_desc *desc = dev_get_uclass_platdata(dev);
 365                 const char *if_typename = blk_get_if_type_name(desc->if_type);
 366
 367                 /* Add block device for the full device */
 368                 printf("Scanning disk %s...\n", dev->name);
 369                 ret = efi_disk_add_dev(NULL, NULL, if_typename,
 370                                         desc, desc->devnum, 0, 0, &disk);
 371                 if (ret == EFI_NOT_READY) {
 372                         printf("Disk %s not ready\n", dev->name);
 373                         continue;
 374                 }
 375                 if (ret) {
 376                         printf("ERROR: failure to add disk device %s, r = %lu\n",
 377                                dev->name, ret & ~EFI_ERROR_MASK);
 378                         return ret;
 379                 }
 380                 disks++;
 381
 382                 /* Partitions show up as block devices in EFI */
 383                 disks += efi_disk_create_partitions(
 384                                         disk->parent.handle, desc, if_typename,
 385                                         desc->devnum, dev->name);
 386         }
 387 #else
 388         int i, if_type;
 389
 390         /* Search for all available disk devices */
 391         for (if_type = 0; if_type < IF_TYPE_COUNT; if_type++) {
 392                 const struct blk_driver *cur_drvr;
 393                 const char *if_typename;
 394
 395                 cur_drvr = blk_driver_lookup_type(if_type);
 396                 if (!cur_drvr)
 397                         continue;
 398
 399                 if_typename = cur_drvr->if_typename;
 400                 printf("Scanning disks on %s...\n", if_typename);
 401                 for (i = 0; i < 4; i++) {
 402                         struct blk_desc *desc;
 403                         char devname[32] = { 0 }; /* dp->str is u16[32] long */
 404
 405                         desc = blk_get_devnum_by_type(if_type, i);
 406                         if (!desc)
 407                                 continue;
 408                         if (desc->type == DEV_TYPE_UNKNOWN)
 409                                 continue;
 410
 411                         snprintf(devname, sizeof(devname), "%s%d",
 412                                  if_typename, i);
 413
 414                         /* Add block device for the full device */
 415                         ret = efi_disk_add_dev(NULL, NULL, if_typename, desc,
 416                                                i, 0, 0, &disk);
 417                         if (ret == EFI_NOT_READY) {
 418                                 printf("Disk %s not ready\n", devname);
 419                                 continue;
 420                         }
 421                         if (ret) {
 422                                 printf("ERROR: failure to add disk device %s, r = %lu\n",
 423                                        devname, ret & ~EFI_ERROR_MASK);
 424                                 return ret;
 425                         }
 426                         disks++;
 427
 428                         /* Partitions show up as block devices in EFI */
 429                         disks += efi_disk_create_partitions(
 430                                                 disk->parent.handle, desc,
 431                                                 if_typename, i, devname);
 432                 }
 433         }
 434 #endif
 435         printf("Found %d disks\n", disks);
 436
 437         return EFI_SUCCESS;
 438 }