1 // SPDX-License-Identifier: GPL-2.0+
3 * EFI application disk support
5 * Copyright (c) 2016 Alexander Graf
11 #include <efi_loader.h>
16 const efi_guid_t efi_block_io_guid = EFI_BLOCK_IO_PROTOCOL_GUID;
19 * struct efi_disk_obj - EFI disk object
21 * @header: EFI object header
22 * @ops: EFI disk I/O protocol interface
23 * @ifname: interface name for block device
24 * @dev_index: device index of block device
25 * @media: block I/O media information
26 * @dp: device path to the block device
28 * @volume: simple file system protocol of the partition
29 * @offset: offset into disk for simple partition
30 * @desc: internal block device descriptor
33 struct efi_object header;
34 struct efi_block_io ops;
37 struct efi_block_io_media media;
38 struct efi_device_path *dp;
40 struct efi_simple_file_system_protocol *volume;
42 struct blk_desc *desc;
46 * efi_disk_reset() - reset block device
48 * This function implements the Reset service of the EFI_BLOCK_IO_PROTOCOL.
50 * As U-Boot's block devices do not have a reset function simply return
53 * See the Unified Extensible Firmware Interface (UEFI) specification for
56 * @this: pointer to the BLOCK_IO_PROTOCOL
57 * @extended_verification: extended verification
60 static efi_status_t EFIAPI efi_disk_reset(struct efi_block_io *this,
61 char extended_verification)
63 EFI_ENTRY("%p, %x", this, extended_verification);
64 return EFI_EXIT(EFI_SUCCESS);
67 enum efi_disk_direction {
72 static efi_status_t efi_disk_rw_blocks(struct efi_block_io *this,
73 u32 media_id, u64 lba, unsigned long buffer_size,
74 void *buffer, enum efi_disk_direction direction)
76 struct efi_disk_obj *diskobj;
77 struct blk_desc *desc;
82 diskobj = container_of(this, struct efi_disk_obj, ops);
83 desc = (struct blk_desc *) diskobj->desc;
85 blocks = buffer_size / blksz;
86 lba += diskobj->offset;
88 EFI_PRINT("blocks=%x lba=%llx blksz=%x dir=%d\n",
89 blocks, lba, blksz, direction);
91 /* We only support full block access */
92 if (buffer_size & (blksz - 1))
93 return EFI_BAD_BUFFER_SIZE;
95 if (direction == EFI_DISK_READ)
96 n = blk_dread(desc, lba, blocks, buffer);
98 n = blk_dwrite(desc, lba, blocks, buffer);
100 /* We don't do interrupts, so check for timers cooperatively */
103 EFI_PRINT("n=%lx blocks=%x\n", n, blocks);
106 return EFI_DEVICE_ERROR;
112 * efi_disk_read_blocks() - reads blocks from device
114 * This function implements the ReadBlocks service of the EFI_BLOCK_IO_PROTOCOL.
116 * See the Unified Extensible Firmware Interface (UEFI) specification for
119 * @this: pointer to the BLOCK_IO_PROTOCOL
120 * @media_id: id of the medium to be read from
121 * @lba: starting logical block for reading
122 * @buffer_size: size of the read buffer
123 * @buffer: pointer to the destination buffer
124 * Return: status code
126 static efi_status_t EFIAPI efi_disk_read_blocks(struct efi_block_io *this,
127 u32 media_id, u64 lba, efi_uintn_t buffer_size,
130 void *real_buffer = buffer;
134 return EFI_INVALID_PARAMETER;
135 /* TODO: check for media changes */
136 if (media_id != this->media->media_id)
137 return EFI_MEDIA_CHANGED;
138 if (!this->media->media_present)
140 /* media->io_align is a power of 2 */
141 if ((uintptr_t)buffer & (this->media->io_align - 1))
142 return EFI_INVALID_PARAMETER;
143 if (lba * this->media->block_size + buffer_size >
144 this->media->last_block * this->media->block_size)
145 return EFI_INVALID_PARAMETER;
147 #ifdef CONFIG_EFI_LOADER_BOUNCE_BUFFER
148 if (buffer_size > EFI_LOADER_BOUNCE_BUFFER_SIZE) {
149 r = efi_disk_read_blocks(this, media_id, lba,
150 EFI_LOADER_BOUNCE_BUFFER_SIZE, buffer);
151 if (r != EFI_SUCCESS)
153 return efi_disk_read_blocks(this, media_id, lba +
154 EFI_LOADER_BOUNCE_BUFFER_SIZE / this->media->block_size,
155 buffer_size - EFI_LOADER_BOUNCE_BUFFER_SIZE,
156 buffer + EFI_LOADER_BOUNCE_BUFFER_SIZE);
159 real_buffer = efi_bounce_buffer;
162 EFI_ENTRY("%p, %x, %llx, %zx, %p", this, media_id, lba,
163 buffer_size, buffer);
165 r = efi_disk_rw_blocks(this, media_id, lba, buffer_size, real_buffer,
168 /* Copy from bounce buffer to real buffer if necessary */
169 if ((r == EFI_SUCCESS) && (real_buffer != buffer))
170 memcpy(buffer, real_buffer, buffer_size);
176 * efi_disk_write_blocks() - writes blocks to device
178 * This function implements the WriteBlocks service of the
179 * EFI_BLOCK_IO_PROTOCOL.
181 * See the Unified Extensible Firmware Interface (UEFI) specification for
184 * @this: pointer to the BLOCK_IO_PROTOCOL
185 * @media_id: id of the medium to be written to
186 * @lba: starting logical block for writing
187 * @buffer_size: size of the write buffer
188 * @buffer: pointer to the source buffer
189 * Return: status code
191 static efi_status_t EFIAPI efi_disk_write_blocks(struct efi_block_io *this,
192 u32 media_id, u64 lba, efi_uintn_t buffer_size,
195 void *real_buffer = buffer;
199 return EFI_INVALID_PARAMETER;
200 if (this->media->read_only)
201 return EFI_WRITE_PROTECTED;
202 /* TODO: check for media changes */
203 if (media_id != this->media->media_id)
204 return EFI_MEDIA_CHANGED;
205 if (!this->media->media_present)
207 /* media->io_align is a power of 2 */
208 if ((uintptr_t)buffer & (this->media->io_align - 1))
209 return EFI_INVALID_PARAMETER;
210 if (lba * this->media->block_size + buffer_size >
211 this->media->last_block * this->media->block_size)
212 return EFI_INVALID_PARAMETER;
214 #ifdef CONFIG_EFI_LOADER_BOUNCE_BUFFER
215 if (buffer_size > EFI_LOADER_BOUNCE_BUFFER_SIZE) {
216 r = efi_disk_write_blocks(this, media_id, lba,
217 EFI_LOADER_BOUNCE_BUFFER_SIZE, buffer);
218 if (r != EFI_SUCCESS)
220 return efi_disk_write_blocks(this, media_id, lba +
221 EFI_LOADER_BOUNCE_BUFFER_SIZE / this->media->block_size,
222 buffer_size - EFI_LOADER_BOUNCE_BUFFER_SIZE,
223 buffer + EFI_LOADER_BOUNCE_BUFFER_SIZE);
226 real_buffer = efi_bounce_buffer;
229 EFI_ENTRY("%p, %x, %llx, %zx, %p", this, media_id, lba,
230 buffer_size, buffer);
232 /* Populate bounce buffer if necessary */
233 if (real_buffer != buffer)
234 memcpy(real_buffer, buffer, buffer_size);
236 r = efi_disk_rw_blocks(this, media_id, lba, buffer_size, real_buffer,
243 * efi_disk_flush_blocks() - flushes modified data to the device
245 * This function implements the FlushBlocks service of the
246 * EFI_BLOCK_IO_PROTOCOL.
248 * As we always write synchronously nothing is done here.
250 * See the Unified Extensible Firmware Interface (UEFI) specification for
253 * @this: pointer to the BLOCK_IO_PROTOCOL
254 * Return: status code
256 static efi_status_t EFIAPI efi_disk_flush_blocks(struct efi_block_io *this)
258 EFI_ENTRY("%p", this);
259 return EFI_EXIT(EFI_SUCCESS);
262 static const struct efi_block_io block_io_disk_template = {
263 .reset = &efi_disk_reset,
264 .read_blocks = &efi_disk_read_blocks,
265 .write_blocks = &efi_disk_write_blocks,
266 .flush_blocks = &efi_disk_flush_blocks,
270 * efi_fs_from_path() - retrieve simple file system protocol
272 * Gets the simple file system protocol for a file device path.
274 * The full path provided is split into device part and into a file
275 * part. The device part is used to find the handle on which the
276 * simple file system protocol is installed.
278 * @full_path: device path including device and file
279 * Return: simple file system protocol
281 struct efi_simple_file_system_protocol *
282 efi_fs_from_path(struct efi_device_path *full_path)
284 struct efi_object *efiobj;
285 struct efi_handler *handler;
286 struct efi_device_path *device_path;
287 struct efi_device_path *file_path;
290 /* Split the path into a device part and a file part */
291 ret = efi_dp_split_file_path(full_path, &device_path, &file_path);
292 if (ret != EFI_SUCCESS)
294 efi_free_pool(file_path);
296 /* Get the EFI object for the partition */
297 efiobj = efi_dp_find_obj(device_path, NULL);
298 efi_free_pool(device_path);
302 /* Find the simple file system protocol */
303 ret = efi_search_protocol(efiobj, &efi_simple_file_system_protocol_guid,
305 if (ret != EFI_SUCCESS)
308 /* Return the simple file system protocol for the partition */
309 return handler->protocol_interface;
313 * efi_fs_exists() - check if a partition bears a file system
315 * @desc: block device descriptor
316 * @part: partition number
317 * Return: 1 if a file system exists on the partition
320 static int efi_fs_exists(struct blk_desc *desc, int part)
322 if (fs_set_blk_dev_with_part(desc, part))
325 if (fs_get_type() == FS_TYPE_ANY)
334 * efi_disk_add_dev() - create a handle for a partition or disk
336 * @parent: parent handle
337 * @dp_parent: parent device path
338 * @if_typename: interface name for block device
339 * @desc: internal block device
340 * @dev_index: device index for block device
341 * @offset: offset into disk for simple partitions
343 * @disk: pointer to receive the created handle
344 * Return: disk object
346 static efi_status_t efi_disk_add_dev(
348 struct efi_device_path *dp_parent,
349 const char *if_typename,
350 struct blk_desc *desc,
354 struct efi_disk_obj **disk)
356 struct efi_disk_obj *diskobj;
359 /* Don't add empty devices */
361 return EFI_NOT_READY;
363 diskobj = calloc(1, sizeof(*diskobj));
365 return EFI_OUT_OF_RESOURCES;
367 /* Hook up to the device list */
368 efi_add_handle(&diskobj->header);
370 /* Fill in object data */
372 struct efi_device_path *node = efi_dp_part_node(desc, part);
374 diskobj->dp = efi_dp_append_node(dp_parent, node);
377 diskobj->dp = efi_dp_from_part(desc, part);
379 diskobj->part = part;
380 ret = efi_add_protocol(&diskobj->header, &efi_block_io_guid,
382 if (ret != EFI_SUCCESS)
384 ret = efi_add_protocol(&diskobj->header, &efi_guid_device_path,
386 if (ret != EFI_SUCCESS)
388 /* partitions or whole disk without partitions */
389 if ((part || desc->part_type == PART_TYPE_UNKNOWN) &&
390 efi_fs_exists(desc, part)) {
391 diskobj->volume = efi_simple_file_system(desc, part,
393 ret = efi_add_protocol(&diskobj->header,
394 &efi_simple_file_system_protocol_guid,
396 if (ret != EFI_SUCCESS)
399 diskobj->ops = block_io_disk_template;
400 diskobj->ifname = if_typename;
401 diskobj->dev_index = dev_index;
402 diskobj->offset = offset;
403 diskobj->desc = desc;
405 /* Fill in EFI IO Media info (for read/write callbacks) */
406 diskobj->media.removable_media = desc->removable;
407 diskobj->media.media_present = 1;
409 * MediaID is just an arbitrary counter.
410 * We have to change it if the medium is removed or changed.
412 diskobj->media.media_id = 1;
413 diskobj->media.block_size = desc->blksz;
414 diskobj->media.io_align = desc->blksz;
415 diskobj->media.last_block = desc->lba - offset;
417 diskobj->media.logical_partition = 1;
418 diskobj->ops.media = &diskobj->media;
425 * efi_disk_create_partitions() - create handles and protocols for partitions
427 * Create handles and protocols for the partitions of a block device.
429 * @parent: handle of the parent disk
430 * @desc: block device
431 * @if_typename: interface type
432 * @diskid: device number
433 * @pdevname: device name
434 * Return: number of partitions created
436 int efi_disk_create_partitions(efi_handle_t parent, struct blk_desc *desc,
437 const char *if_typename, int diskid,
438 const char *pdevname)
441 char devname[32] = { 0 }; /* dp->str is u16[32] long */
442 disk_partition_t info;
444 struct efi_device_path *dp = NULL;
446 struct efi_handler *handler;
448 /* Get the device path of the parent */
449 ret = efi_search_protocol(parent, &efi_guid_device_path, &handler);
450 if (ret == EFI_SUCCESS)
451 dp = handler->protocol_interface;
453 /* Add devices for each partition */
454 for (part = 1; part <= MAX_SEARCH_PARTITIONS; part++) {
455 if (part_get_info(desc, part, &info))
457 snprintf(devname, sizeof(devname), "%s:%d", pdevname,
459 ret = efi_disk_add_dev(parent, dp, if_typename, desc, diskid,
460 info.start, part, NULL);
461 if (ret != EFI_SUCCESS) {
462 printf("Adding partition %s failed\n", pdevname);
472 * efi_disk_register() - register block devices
474 * U-Boot doesn't have a list of all online disk devices. So when running our
475 * EFI payload, we scan through all of the potentially available ones and
476 * store them in our object pool.
478 * This function is called in efi_init_obj_list().
480 * TODO(sjg@chromium.org): Actually with CONFIG_BLK, U-Boot does have this.
481 * Consider converting the code to look up devices as needed. The EFI device
482 * could be a child of the UCLASS_BLK block device, perhaps.
484 * Return: status code
486 efi_status_t efi_disk_register(void)
488 struct efi_disk_obj *disk;
494 for (uclass_first_device_check(UCLASS_BLK, &dev); dev;
495 uclass_next_device_check(&dev)) {
496 struct blk_desc *desc = dev_get_uclass_platdata(dev);
497 const char *if_typename = blk_get_if_type_name(desc->if_type);
499 /* Add block device for the full device */
500 printf("Scanning disk %s...\n", dev->name);
501 ret = efi_disk_add_dev(NULL, NULL, if_typename,
502 desc, desc->devnum, 0, 0, &disk);
503 if (ret == EFI_NOT_READY) {
504 printf("Disk %s not ready\n", dev->name);
508 printf("ERROR: failure to add disk device %s, r = %lu\n",
509 dev->name, ret & ~EFI_ERROR_MASK);
514 /* Partitions show up as block devices in EFI */
515 disks += efi_disk_create_partitions(
516 &disk->header, desc, if_typename,
517 desc->devnum, dev->name);
522 /* Search for all available disk devices */
523 for (if_type = 0; if_type < IF_TYPE_COUNT; if_type++) {
524 const struct blk_driver *cur_drvr;
525 const char *if_typename;
527 cur_drvr = blk_driver_lookup_type(if_type);
531 if_typename = cur_drvr->if_typename;
532 printf("Scanning disks on %s...\n", if_typename);
533 for (i = 0; i < 4; i++) {
534 struct blk_desc *desc;
535 char devname[32] = { 0 }; /* dp->str is u16[32] long */
537 desc = blk_get_devnum_by_type(if_type, i);
540 if (desc->type == DEV_TYPE_UNKNOWN)
543 snprintf(devname, sizeof(devname), "%s%d",
546 /* Add block device for the full device */
547 ret = efi_disk_add_dev(NULL, NULL, if_typename, desc,
549 if (ret == EFI_NOT_READY) {
550 printf("Disk %s not ready\n", devname);
554 printf("ERROR: failure to add disk device %s, r = %lu\n",
555 devname, ret & ~EFI_ERROR_MASK);
560 /* Partitions show up as block devices in EFI */
561 disks += efi_disk_create_partitions
562 (&disk->header, desc,
563 if_typename, i, devname);
567 printf("Found %d disks\n", disks);