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 = EFI_BLOCK_IO_PROTOCOL_GUID;
  16
  17 /**
  18  * struct efi_disk_obj - EFI disk object
  19  *
  20  * @header:     EFI object header
  21  * @ops:        EFI disk I/O protocol interface
  22  * @ifname:     interface name for block device
  23  * @dev_index:  device index of block device
  24  * @media:      block I/O media information
  25  * @dp:         device path to the block device
  26  * @part:       partition
  27  * @volume:     simple file system protocol of the partition
  28  * @offset:     offset into disk for simple partition
  29  * @desc:       internal block device descriptor
  30  */
  31 struct efi_disk_obj {
  32         struct efi_object header;
  33         struct efi_block_io ops;
  34         const char *ifname;
  35         int dev_index;
  36         struct efi_block_io_media media;
  37         struct efi_device_path *dp;
  38         unsigned int part;
  39         struct efi_simple_file_system_protocol *volume;
  40         lbaint_t offset;
  41         struct blk_desc *desc;
  42 };
  43
  44 static efi_status_t EFIAPI efi_disk_reset(struct efi_block_io *this,
  45                         char extended_verification)
  46 {
  47         EFI_ENTRY("%p, %x", this, extended_verification);
  48         return EFI_EXIT(EFI_DEVICE_ERROR);
  49 }
  50
  51 enum efi_disk_direction {
  52         EFI_DISK_READ,
  53         EFI_DISK_WRITE,
  54 };
  55
  56 static efi_status_t efi_disk_rw_blocks(struct efi_block_io *this,
  57                         u32 media_id, u64 lba, unsigned long buffer_size,
  58                         void *buffer, enum efi_disk_direction direction)
  59 {
  60         struct efi_disk_obj *diskobj;
  61         struct blk_desc *desc;
  62         int blksz;
  63         int blocks;
  64         unsigned long n;
  65
  66         diskobj = container_of(this, struct efi_disk_obj, ops);
  67         desc = (struct blk_desc *) diskobj->desc;
  68         blksz = desc->blksz;
  69         blocks = buffer_size / blksz;
  70         lba += diskobj->offset;
  71
  72         EFI_PRINT("blocks=%x lba=%llx blksz=%x dir=%d\n",
  73                   blocks, lba, blksz, direction);
  74
  75         /* We only support full block access */
  76         if (buffer_size & (blksz - 1))
  77                 return EFI_BAD_BUFFER_SIZE;
  78
  79         if (direction == EFI_DISK_READ)
  80                 n = blk_dread(desc, lba, blocks, buffer);
  81         else
  82                 n = blk_dwrite(desc, lba, blocks, buffer);
  83
  84         /* We don't do interrupts, so check for timers cooperatively */
  85         efi_timer_check();
  86
  87         EFI_PRINT("n=%lx blocks=%x\n", n, blocks);
  88
  89         if (n != blocks)
  90                 return EFI_DEVICE_ERROR;
  91
  92         return EFI_SUCCESS;
  93 }
  94
  95 static efi_status_t EFIAPI efi_disk_read_blocks(struct efi_block_io *this,
  96                         u32 media_id, u64 lba, efi_uintn_t buffer_size,
  97                         void *buffer)
  98 {
  99         void *real_buffer = buffer;
 100         efi_status_t r;
 101
 102         if (!this)
 103                 return EFI_INVALID_PARAMETER;
 104         /* TODO: check for media changes */
 105         if (media_id != this->media->media_id)
 106                 return EFI_MEDIA_CHANGED;
 107         if (!this->media->media_present)
 108                 return EFI_NO_MEDIA;
 109         /* media->io_align is a power of 2 */
 110         if ((uintptr_t)buffer & (this->media->io_align - 1))
 111                 return EFI_INVALID_PARAMETER;
 112         if (lba * this->media->block_size + buffer_size >
 113             this->media->last_block * this->media->block_size)
 114                 return EFI_INVALID_PARAMETER;
 115
 116 #ifdef CONFIG_EFI_LOADER_BOUNCE_BUFFER
 117         if (buffer_size > EFI_LOADER_BOUNCE_BUFFER_SIZE) {
 118                 r = efi_disk_read_blocks(this, media_id, lba,
 119                         EFI_LOADER_BOUNCE_BUFFER_SIZE, buffer);
 120                 if (r != EFI_SUCCESS)
 121                         return r;
 122                 return efi_disk_read_blocks(this, media_id, lba +
 123                         EFI_LOADER_BOUNCE_BUFFER_SIZE / this->media->block_size,
 124                         buffer_size - EFI_LOADER_BOUNCE_BUFFER_SIZE,
 125                         buffer + EFI_LOADER_BOUNCE_BUFFER_SIZE);
 126         }
 127
 128         real_buffer = efi_bounce_buffer;
 129 #endif
 130
 131         EFI_ENTRY("%p, %x, %llx, %zx, %p", this, media_id, lba,
 132                   buffer_size, buffer);
 133
 134         r = efi_disk_rw_blocks(this, media_id, lba, buffer_size, real_buffer,
 135                                EFI_DISK_READ);
 136
 137         /* Copy from bounce buffer to real buffer if necessary */
 138         if ((r == EFI_SUCCESS) && (real_buffer != buffer))
 139                 memcpy(buffer, real_buffer, buffer_size);
 140
 141         return EFI_EXIT(r);
 142 }
 143
 144 static efi_status_t EFIAPI efi_disk_write_blocks(struct efi_block_io *this,
 145                         u32 media_id, u64 lba, efi_uintn_t buffer_size,
 146                         void *buffer)
 147 {
 148         void *real_buffer = buffer;
 149         efi_status_t r;
 150
 151         if (!this)
 152                 return EFI_INVALID_PARAMETER;
 153         if (this->media->read_only)
 154                 return EFI_WRITE_PROTECTED;
 155         /* TODO: check for media changes */
 156         if (media_id != this->media->media_id)
 157                 return EFI_MEDIA_CHANGED;
 158         if (!this->media->media_present)
 159                 return EFI_NO_MEDIA;
 160         /* media->io_align is a power of 2 */
 161         if ((uintptr_t)buffer & (this->media->io_align - 1))
 162                 return EFI_INVALID_PARAMETER;
 163         if (lba * this->media->block_size + buffer_size >
 164             this->media->last_block * this->media->block_size)
 165                 return EFI_INVALID_PARAMETER;
 166
 167 #ifdef CONFIG_EFI_LOADER_BOUNCE_BUFFER
 168         if (buffer_size > EFI_LOADER_BOUNCE_BUFFER_SIZE) {
 169                 r = efi_disk_write_blocks(this, media_id, lba,
 170                         EFI_LOADER_BOUNCE_BUFFER_SIZE, buffer);
 171                 if (r != EFI_SUCCESS)
 172                         return r;
 173                 return efi_disk_write_blocks(this, media_id, lba +
 174                         EFI_LOADER_BOUNCE_BUFFER_SIZE / this->media->block_size,
 175                         buffer_size - EFI_LOADER_BOUNCE_BUFFER_SIZE,
 176                         buffer + EFI_LOADER_BOUNCE_BUFFER_SIZE);
 177         }
 178
 179         real_buffer = efi_bounce_buffer;
 180 #endif
 181
 182         EFI_ENTRY("%p, %x, %llx, %zx, %p", this, media_id, lba,
 183                   buffer_size, buffer);
 184
 185         /* Populate bounce buffer if necessary */
 186         if (real_buffer != buffer)
 187                 memcpy(real_buffer, buffer, buffer_size);
 188
 189         r = efi_disk_rw_blocks(this, media_id, lba, buffer_size, real_buffer,
 190                                EFI_DISK_WRITE);
 191
 192         return EFI_EXIT(r);
 193 }
 194
 195 static efi_status_t EFIAPI efi_disk_flush_blocks(struct efi_block_io *this)
 196 {
 197         /* We always write synchronously */
 198         EFI_ENTRY("%p", this);
 199         return EFI_EXIT(EFI_SUCCESS);
 200 }
 201
 202 static const struct efi_block_io block_io_disk_template = {
 203         .reset = &efi_disk_reset,
 204         .read_blocks = &efi_disk_read_blocks,
 205         .write_blocks = &efi_disk_write_blocks,
 206         .flush_blocks = &efi_disk_flush_blocks,
 207 };
 208
 209 /*
 210  * Get the simple file system protocol for a file device path.
 211  *
 212  * The full path provided is split into device part and into a file
 213  * part. The device part is used to find the handle on which the
 214  * simple file system protocol is installed.
 215  *
 216  * @full_path   device path including device and file
 217  * @return      simple file system protocol
 218  */
 219 struct efi_simple_file_system_protocol *
 220 efi_fs_from_path(struct efi_device_path *full_path)
 221 {
 222         struct efi_object *efiobj;
 223         struct efi_handler *handler;
 224         struct efi_device_path *device_path;
 225         struct efi_device_path *file_path;
 226         efi_status_t ret;
 227
 228         /* Split the path into a device part and a file part */
 229         ret = efi_dp_split_file_path(full_path, &device_path, &file_path);
 230         if (ret != EFI_SUCCESS)
 231                 return NULL;
 232         efi_free_pool(file_path);
 233
 234         /* Get the EFI object for the partition */
 235         efiobj = efi_dp_find_obj(device_path, NULL);
 236         efi_free_pool(device_path);
 237         if (!efiobj)
 238                 return NULL;
 239
 240         /* Find the simple file system protocol */
 241         ret = efi_search_protocol(efiobj, &efi_simple_file_system_protocol_guid,
 242                                   &handler);
 243         if (ret != EFI_SUCCESS)
 244                 return NULL;
 245
 246         /* Return the simple file system protocol for the partition */
 247         return handler->protocol_interface;
 248 }
 249
 250 /*
 251  * Create a handle for a partition or disk
 252  *
 253  * @parent      parent handle
 254  * @dp_parent   parent device path
 255  * @if_typename interface name for block device
 256  * @desc        internal block device
 257  * @dev_index   device index for block device
 258  * @offset      offset into disk for simple partitions
 259  * @return      disk object
 260  */
 261 static efi_status_t efi_disk_add_dev(
 262                                 efi_handle_t parent,
 263                                 struct efi_device_path *dp_parent,
 264                                 const char *if_typename,
 265                                 struct blk_desc *desc,
 266                                 int dev_index,
 267                                 lbaint_t offset,
 268                                 unsigned int part,
 269                                 struct efi_disk_obj **disk)
 270 {
 271         struct efi_disk_obj *diskobj;
 272         efi_status_t ret;
 273
 274         /* Don't add empty devices */
 275         if (!desc->lba)
 276                 return EFI_NOT_READY;
 277
 278         diskobj = calloc(1, sizeof(*diskobj));
 279         if (!diskobj)
 280                 return EFI_OUT_OF_RESOURCES;
 281
 282         /* Hook up to the device list */
 283         efi_add_handle(&diskobj->header);
 284
 285         /* Fill in object data */
 286         if (part) {
 287                 struct efi_device_path *node = efi_dp_part_node(desc, part);
 288
 289                 diskobj->dp = efi_dp_append_node(dp_parent, node);
 290                 efi_free_pool(node);
 291         } else {
 292                 diskobj->dp = efi_dp_from_part(desc, part);
 293         }
 294         diskobj->part = part;
 295         ret = efi_add_protocol(&diskobj->header, &efi_block_io_guid,
 296                                &diskobj->ops);
 297         if (ret != EFI_SUCCESS)
 298                 return ret;
 299         ret = efi_add_protocol(&diskobj->header, &efi_guid_device_path,
 300                                diskobj->dp);
 301         if (ret != EFI_SUCCESS)
 302                 return ret;
 303         if (part >= 1) {
 304                 diskobj->volume = efi_simple_file_system(desc, part,
 305                                                          diskobj->dp);
 306                 ret = efi_add_protocol(&diskobj->header,
 307                                        &efi_simple_file_system_protocol_guid,
 308                                        diskobj->volume);
 309                 if (ret != EFI_SUCCESS)
 310                         return ret;
 311         }
 312         diskobj->ops = block_io_disk_template;
 313         diskobj->ifname = if_typename;
 314         diskobj->dev_index = dev_index;
 315         diskobj->offset = offset;
 316         diskobj->desc = desc;
 317
 318         /* Fill in EFI IO Media info (for read/write callbacks) */
 319         diskobj->media.removable_media = desc->removable;
 320         diskobj->media.media_present = 1;
 321         /*
 322          * MediaID is just an arbitrary counter.
 323          * We have to change it if the medium is removed or changed.
 324          */
 325         diskobj->media.media_id = 1;
 326         diskobj->media.block_size = desc->blksz;
 327         diskobj->media.io_align = desc->blksz;
 328         diskobj->media.last_block = desc->lba - offset;
 329         if (part != 0)
 330                 diskobj->media.logical_partition = 1;
 331         diskobj->ops.media = &diskobj->media;
 332         if (disk)
 333                 *disk = diskobj;
 334         return EFI_SUCCESS;
 335 }
 336
 337 /*
 338  * Create handles and protocols for the partitions of a block device
 339  *
 340  * @parent              handle of the parent disk
 341  * @blk_desc            block device
 342  * @if_typename         interface type
 343  * @diskid              device number
 344  * @pdevname            device name
 345  * @return              number of partitions created
 346  */
 347 int efi_disk_create_partitions(efi_handle_t parent, struct blk_desc *desc,
 348                                const char *if_typename, int diskid,
 349                                const char *pdevname)
 350 {
 351         int disks = 0;
 352         char devname[32] = { 0 }; /* dp->str is u16[32] long */
 353         disk_partition_t info;
 354         int part;
 355         struct efi_device_path *dp = NULL;
 356         efi_status_t ret;
 357         struct efi_handler *handler;
 358
 359         /* Get the device path of the parent */
 360         ret = efi_search_protocol(parent, &efi_guid_device_path, &handler);
 361         if (ret == EFI_SUCCESS)
 362                 dp = handler->protocol_interface;
 363
 364         /* Add devices for each partition */
 365         for (part = 1; part <= MAX_SEARCH_PARTITIONS; part++) {
 366                 if (part_get_info(desc, part, &info))
 367                         continue;
 368                 snprintf(devname, sizeof(devname), "%s:%d", pdevname,
 369                          part);
 370                 ret = efi_disk_add_dev(parent, dp, if_typename, desc, diskid,
 371                                        info.start, part, NULL);
 372                 if (ret != EFI_SUCCESS) {
 373                         printf("Adding partition %s failed\n", pdevname);
 374                         continue;
 375                 }
 376                 disks++;
 377         }
 378
 379         return disks;
 380 }
 381
 382 /*
 383  * U-Boot doesn't have a list of all online disk devices. So when running our
 384  * EFI payload, we scan through all of the potentially available ones and
 385  * store them in our object pool.
 386  *
 387  * TODO(sjg@chromium.org): Actually with CONFIG_BLK, U-Boot does have this.
 388  * Consider converting the code to look up devices as needed. The EFI device
 389  * could be a child of the UCLASS_BLK block device, perhaps.
 390  *
 391  * This gets called from do_bootefi_exec().
 392  */
 393 efi_status_t efi_disk_register(void)
 394 {
 395         struct efi_disk_obj *disk;
 396         int disks = 0;
 397         efi_status_t ret;
 398 #ifdef CONFIG_BLK
 399         struct udevice *dev;
 400
 401         for (uclass_first_device_check(UCLASS_BLK, &dev); dev;
 402              uclass_next_device_check(&dev)) {
 403                 struct blk_desc *desc = dev_get_uclass_platdata(dev);
 404                 const char *if_typename = blk_get_if_type_name(desc->if_type);
 405
 406                 /* Add block device for the full device */
 407                 printf("Scanning disk %s...\n", dev->name);
 408                 ret = efi_disk_add_dev(NULL, NULL, if_typename,
 409                                         desc, desc->devnum, 0, 0, &disk);
 410                 if (ret == EFI_NOT_READY) {
 411                         printf("Disk %s not ready\n", dev->name);
 412                         continue;
 413                 }
 414                 if (ret) {
 415                         printf("ERROR: failure to add disk device %s, r = %lu\n",
 416                                dev->name, ret & ~EFI_ERROR_MASK);
 417                         return ret;
 418                 }
 419                 disks++;
 420
 421                 /* Partitions show up as block devices in EFI */
 422                 disks += efi_disk_create_partitions(
 423                                         &disk->header, desc, if_typename,
 424                                         desc->devnum, dev->name);
 425         }
 426 #else
 427         int i, if_type;
 428
 429         /* Search for all available disk devices */
 430         for (if_type = 0; if_type < IF_TYPE_COUNT; if_type++) {
 431                 const struct blk_driver *cur_drvr;
 432                 const char *if_typename;
 433
 434                 cur_drvr = blk_driver_lookup_type(if_type);
 435                 if (!cur_drvr)
 436                         continue;
 437
 438                 if_typename = cur_drvr->if_typename;
 439                 printf("Scanning disks on %s...\n", if_typename);
 440                 for (i = 0; i < 4; i++) {
 441                         struct blk_desc *desc;
 442                         char devname[32] = { 0 }; /* dp->str is u16[32] long */
 443
 444                         desc = blk_get_devnum_by_type(if_type, i);
 445                         if (!desc)
 446                                 continue;
 447                         if (desc->type == DEV_TYPE_UNKNOWN)
 448                                 continue;
 449
 450                         snprintf(devname, sizeof(devname), "%s%d",
 451                                  if_typename, i);
 452
 453                         /* Add block device for the full device */
 454                         ret = efi_disk_add_dev(NULL, NULL, if_typename, desc,
 455                                                i, 0, 0, &disk);
 456                         if (ret == EFI_NOT_READY) {
 457                                 printf("Disk %s not ready\n", devname);
 458                                 continue;
 459                         }
 460                         if (ret) {
 461                                 printf("ERROR: failure to add disk device %s, r = %lu\n",
 462                                        devname, ret & ~EFI_ERROR_MASK);
 463                                 return ret;
 464                         }
 465                         disks++;
 466
 467                         /* Partitions show up as block devices in EFI */
 468                         disks += efi_disk_create_partitions
 469                                                 (&disk->header, desc,
 470                                                  if_typename, i, devname);
 471                 }
 472         }
 473 #endif
 474         printf("Found %d disks\n", disks);
 475
 476         return EFI_SUCCESS;
 477 }