1 // SPDX-License-Identifier: GPL-2.0+
3 * EFI application disk support
5 * Copyright (c) 2016 Alexander Graf
11 #include <efi_loader.h>
16 struct efi_system_partition efi_system_partition;
18 const efi_guid_t efi_block_io_guid = EFI_BLOCK_IO_PROTOCOL_GUID;
21 * struct efi_disk_obj - EFI disk object
23 * @header: EFI object header
24 * @ops: EFI disk I/O protocol interface
25 * @ifname: interface name for block device
26 * @dev_index: device index of block device
27 * @media: block I/O media information
28 * @dp: device path to the block device
30 * @volume: simple file system protocol of the partition
31 * @offset: offset into disk for simple partition
32 * @desc: internal block device descriptor
35 struct efi_object header;
36 struct efi_block_io ops;
39 struct efi_block_io_media media;
40 struct efi_device_path *dp;
42 struct efi_simple_file_system_protocol *volume;
44 struct blk_desc *desc;
48 * efi_disk_reset() - reset block device
50 * This function implements the Reset service of the EFI_BLOCK_IO_PROTOCOL.
52 * As U-Boot's block devices do not have a reset function simply return
55 * See the Unified Extensible Firmware Interface (UEFI) specification for
58 * @this: pointer to the BLOCK_IO_PROTOCOL
59 * @extended_verification: extended verification
62 static efi_status_t EFIAPI efi_disk_reset(struct efi_block_io *this,
63 char extended_verification)
65 EFI_ENTRY("%p, %x", this, extended_verification);
66 return EFI_EXIT(EFI_SUCCESS);
69 enum efi_disk_direction {
74 static efi_status_t efi_disk_rw_blocks(struct efi_block_io *this,
75 u32 media_id, u64 lba, unsigned long buffer_size,
76 void *buffer, enum efi_disk_direction direction)
78 struct efi_disk_obj *diskobj;
79 struct blk_desc *desc;
84 diskobj = container_of(this, struct efi_disk_obj, ops);
85 desc = (struct blk_desc *) diskobj->desc;
87 blocks = buffer_size / blksz;
88 lba += diskobj->offset;
90 EFI_PRINT("blocks=%x lba=%llx blksz=%x dir=%d\n",
91 blocks, lba, blksz, direction);
93 /* We only support full block access */
94 if (buffer_size & (blksz - 1))
95 return EFI_BAD_BUFFER_SIZE;
97 if (direction == EFI_DISK_READ)
98 n = blk_dread(desc, lba, blocks, buffer);
100 n = blk_dwrite(desc, lba, blocks, buffer);
102 /* We don't do interrupts, so check for timers cooperatively */
105 EFI_PRINT("n=%lx blocks=%x\n", n, blocks);
108 return EFI_DEVICE_ERROR;
114 * efi_disk_read_blocks() - reads blocks from device
116 * This function implements the ReadBlocks service of the EFI_BLOCK_IO_PROTOCOL.
118 * See the Unified Extensible Firmware Interface (UEFI) specification for
121 * @this: pointer to the BLOCK_IO_PROTOCOL
122 * @media_id: id of the medium to be read from
123 * @lba: starting logical block for reading
124 * @buffer_size: size of the read buffer
125 * @buffer: pointer to the destination buffer
126 * Return: status code
128 static efi_status_t EFIAPI efi_disk_read_blocks(struct efi_block_io *this,
129 u32 media_id, u64 lba, efi_uintn_t buffer_size,
132 void *real_buffer = buffer;
136 return EFI_INVALID_PARAMETER;
137 /* TODO: check for media changes */
138 if (media_id != this->media->media_id)
139 return EFI_MEDIA_CHANGED;
140 if (!this->media->media_present)
142 /* media->io_align is a power of 2 */
143 if ((uintptr_t)buffer & (this->media->io_align - 1))
144 return EFI_INVALID_PARAMETER;
145 if (lba * this->media->block_size + buffer_size >
146 this->media->last_block * this->media->block_size)
147 return EFI_INVALID_PARAMETER;
149 #ifdef CONFIG_EFI_LOADER_BOUNCE_BUFFER
150 if (buffer_size > EFI_LOADER_BOUNCE_BUFFER_SIZE) {
151 r = efi_disk_read_blocks(this, media_id, lba,
152 EFI_LOADER_BOUNCE_BUFFER_SIZE, buffer);
153 if (r != EFI_SUCCESS)
155 return efi_disk_read_blocks(this, media_id, lba +
156 EFI_LOADER_BOUNCE_BUFFER_SIZE / this->media->block_size,
157 buffer_size - EFI_LOADER_BOUNCE_BUFFER_SIZE,
158 buffer + EFI_LOADER_BOUNCE_BUFFER_SIZE);
161 real_buffer = efi_bounce_buffer;
164 EFI_ENTRY("%p, %x, %llx, %zx, %p", this, media_id, lba,
165 buffer_size, buffer);
167 r = efi_disk_rw_blocks(this, media_id, lba, buffer_size, real_buffer,
170 /* Copy from bounce buffer to real buffer if necessary */
171 if ((r == EFI_SUCCESS) && (real_buffer != buffer))
172 memcpy(buffer, real_buffer, buffer_size);
178 * efi_disk_write_blocks() - writes blocks to device
180 * This function implements the WriteBlocks service of the
181 * EFI_BLOCK_IO_PROTOCOL.
183 * See the Unified Extensible Firmware Interface (UEFI) specification for
186 * @this: pointer to the BLOCK_IO_PROTOCOL
187 * @media_id: id of the medium to be written to
188 * @lba: starting logical block for writing
189 * @buffer_size: size of the write buffer
190 * @buffer: pointer to the source buffer
191 * Return: status code
193 static efi_status_t EFIAPI efi_disk_write_blocks(struct efi_block_io *this,
194 u32 media_id, u64 lba, efi_uintn_t buffer_size,
197 void *real_buffer = buffer;
201 return EFI_INVALID_PARAMETER;
202 if (this->media->read_only)
203 return EFI_WRITE_PROTECTED;
204 /* TODO: check for media changes */
205 if (media_id != this->media->media_id)
206 return EFI_MEDIA_CHANGED;
207 if (!this->media->media_present)
209 /* media->io_align is a power of 2 */
210 if ((uintptr_t)buffer & (this->media->io_align - 1))
211 return EFI_INVALID_PARAMETER;
212 if (lba * this->media->block_size + buffer_size >
213 this->media->last_block * this->media->block_size)
214 return EFI_INVALID_PARAMETER;
216 #ifdef CONFIG_EFI_LOADER_BOUNCE_BUFFER
217 if (buffer_size > EFI_LOADER_BOUNCE_BUFFER_SIZE) {
218 r = efi_disk_write_blocks(this, media_id, lba,
219 EFI_LOADER_BOUNCE_BUFFER_SIZE, buffer);
220 if (r != EFI_SUCCESS)
222 return efi_disk_write_blocks(this, media_id, lba +
223 EFI_LOADER_BOUNCE_BUFFER_SIZE / this->media->block_size,
224 buffer_size - EFI_LOADER_BOUNCE_BUFFER_SIZE,
225 buffer + EFI_LOADER_BOUNCE_BUFFER_SIZE);
228 real_buffer = efi_bounce_buffer;
231 EFI_ENTRY("%p, %x, %llx, %zx, %p", this, media_id, lba,
232 buffer_size, buffer);
234 /* Populate bounce buffer if necessary */
235 if (real_buffer != buffer)
236 memcpy(real_buffer, buffer, buffer_size);
238 r = efi_disk_rw_blocks(this, media_id, lba, buffer_size, real_buffer,
245 * efi_disk_flush_blocks() - flushes modified data to the device
247 * This function implements the FlushBlocks service of the
248 * EFI_BLOCK_IO_PROTOCOL.
250 * As we always write synchronously nothing is done here.
252 * See the Unified Extensible Firmware Interface (UEFI) specification for
255 * @this: pointer to the BLOCK_IO_PROTOCOL
256 * Return: status code
258 static efi_status_t EFIAPI efi_disk_flush_blocks(struct efi_block_io *this)
260 EFI_ENTRY("%p", this);
261 return EFI_EXIT(EFI_SUCCESS);
264 static const struct efi_block_io block_io_disk_template = {
265 .reset = &efi_disk_reset,
266 .read_blocks = &efi_disk_read_blocks,
267 .write_blocks = &efi_disk_write_blocks,
268 .flush_blocks = &efi_disk_flush_blocks,
272 * efi_fs_from_path() - retrieve simple file system protocol
274 * Gets the simple file system protocol for a file device path.
276 * The full path provided is split into device part and into a file
277 * part. The device part is used to find the handle on which the
278 * simple file system protocol is installed.
280 * @full_path: device path including device and file
281 * Return: simple file system protocol
283 struct efi_simple_file_system_protocol *
284 efi_fs_from_path(struct efi_device_path *full_path)
286 struct efi_object *efiobj;
287 struct efi_handler *handler;
288 struct efi_device_path *device_path;
289 struct efi_device_path *file_path;
292 /* Split the path into a device part and a file part */
293 ret = efi_dp_split_file_path(full_path, &device_path, &file_path);
294 if (ret != EFI_SUCCESS)
296 efi_free_pool(file_path);
298 /* Get the EFI object for the partition */
299 efiobj = efi_dp_find_obj(device_path, NULL);
300 efi_free_pool(device_path);
304 /* Find the simple file system protocol */
305 ret = efi_search_protocol(efiobj, &efi_simple_file_system_protocol_guid,
307 if (ret != EFI_SUCCESS)
310 /* Return the simple file system protocol for the partition */
311 return handler->protocol_interface;
315 * efi_fs_exists() - check if a partition bears a file system
317 * @desc: block device descriptor
318 * @part: partition number
319 * Return: 1 if a file system exists on the partition
322 static int efi_fs_exists(struct blk_desc *desc, int part)
324 if (fs_set_blk_dev_with_part(desc, part))
327 if (fs_get_type() == FS_TYPE_ANY)
336 * efi_disk_add_dev() - create a handle for a partition or disk
338 * @parent: parent handle
339 * @dp_parent: parent device path
340 * @if_typename: interface name for block device
341 * @desc: internal block device
342 * @dev_index: device index for block device
343 * @offset: offset into disk for simple partitions
345 * @disk: pointer to receive the created handle
346 * Return: disk object
348 static efi_status_t efi_disk_add_dev(
350 struct efi_device_path *dp_parent,
351 const char *if_typename,
352 struct blk_desc *desc,
356 struct efi_disk_obj **disk)
358 struct efi_disk_obj *diskobj;
359 struct efi_object *handle;
362 /* Don't add empty devices */
364 return EFI_NOT_READY;
366 diskobj = calloc(1, sizeof(*diskobj));
368 return EFI_OUT_OF_RESOURCES;
370 /* Hook up to the device list */
371 efi_add_handle(&diskobj->header);
373 /* Fill in object data */
375 struct efi_device_path *node = efi_dp_part_node(desc, part);
377 diskobj->dp = efi_dp_append_node(dp_parent, node);
380 diskobj->dp = efi_dp_from_part(desc, part);
382 diskobj->part = part;
385 * Install the device path and the block IO protocol.
387 * InstallMultipleProtocolInterfaces() checks if the device path is
388 * already installed on an other handle and returns EFI_ALREADY_STARTED
391 handle = &diskobj->header;
392 ret = EFI_CALL(efi_install_multiple_protocol_interfaces(
393 &handle, &efi_guid_device_path, diskobj->dp,
394 &efi_block_io_guid, &diskobj->ops, NULL));
395 if (ret != EFI_SUCCESS)
399 * On partitions or whole disks without partitions install the
400 * simple file system protocol if a file system is available.
402 if ((part || desc->part_type == PART_TYPE_UNKNOWN) &&
403 efi_fs_exists(desc, part)) {
404 diskobj->volume = efi_simple_file_system(desc, part,
406 ret = efi_add_protocol(&diskobj->header,
407 &efi_simple_file_system_protocol_guid,
409 if (ret != EFI_SUCCESS)
412 diskobj->ops = block_io_disk_template;
413 diskobj->ifname = if_typename;
414 diskobj->dev_index = dev_index;
415 diskobj->offset = offset;
416 diskobj->desc = desc;
418 /* Fill in EFI IO Media info (for read/write callbacks) */
419 diskobj->media.removable_media = desc->removable;
420 diskobj->media.media_present = 1;
422 * MediaID is just an arbitrary counter.
423 * We have to change it if the medium is removed or changed.
425 diskobj->media.media_id = 1;
426 diskobj->media.block_size = desc->blksz;
427 diskobj->media.io_align = desc->blksz;
428 diskobj->media.last_block = desc->lba - offset;
430 diskobj->media.logical_partition = 1;
431 diskobj->ops.media = &diskobj->media;
435 /* Store first EFI system partition */
436 if (part && !efi_system_partition.if_type) {
438 struct disk_partition info;
440 r = part_get_info(desc, part, &info);
442 return EFI_DEVICE_ERROR;
443 if (info.bootable & PART_EFI_SYSTEM_PARTITION) {
444 efi_system_partition.if_type = desc->if_type;
445 efi_system_partition.devnum = desc->devnum;
446 efi_system_partition.part = part;
447 EFI_PRINT("EFI system partition: %s %d:%d\n",
448 blk_get_if_type_name(desc->if_type),
456 * efi_disk_create_partitions() - create handles and protocols for partitions
458 * Create handles and protocols for the partitions of a block device.
460 * @parent: handle of the parent disk
461 * @desc: block device
462 * @if_typename: interface type
463 * @diskid: device number
464 * @pdevname: device name
465 * Return: number of partitions created
467 int efi_disk_create_partitions(efi_handle_t parent, struct blk_desc *desc,
468 const char *if_typename, int diskid,
469 const char *pdevname)
472 char devname[32] = { 0 }; /* dp->str is u16[32] long */
473 struct disk_partition info;
475 struct efi_device_path *dp = NULL;
477 struct efi_handler *handler;
479 /* Get the device path of the parent */
480 ret = efi_search_protocol(parent, &efi_guid_device_path, &handler);
481 if (ret == EFI_SUCCESS)
482 dp = handler->protocol_interface;
484 /* Add devices for each partition */
485 for (part = 1; part <= MAX_SEARCH_PARTITIONS; part++) {
486 if (part_get_info(desc, part, &info))
488 snprintf(devname, sizeof(devname), "%s:%d", pdevname,
490 ret = efi_disk_add_dev(parent, dp, if_typename, desc, diskid,
491 info.start, part, NULL);
492 if (ret != EFI_SUCCESS) {
493 printf("Adding partition %s failed\n", pdevname);
503 * efi_disk_register() - register block devices
505 * U-Boot doesn't have a list of all online disk devices. So when running our
506 * EFI payload, we scan through all of the potentially available ones and
507 * store them in our object pool.
509 * This function is called in efi_init_obj_list().
511 * TODO(sjg@chromium.org): Actually with CONFIG_BLK, U-Boot does have this.
512 * Consider converting the code to look up devices as needed. The EFI device
513 * could be a child of the UCLASS_BLK block device, perhaps.
515 * Return: status code
517 efi_status_t efi_disk_register(void)
519 struct efi_disk_obj *disk;
525 for (uclass_first_device_check(UCLASS_BLK, &dev); dev;
526 uclass_next_device_check(&dev)) {
527 struct blk_desc *desc = dev_get_uclass_platdata(dev);
528 const char *if_typename = blk_get_if_type_name(desc->if_type);
530 /* Add block device for the full device */
531 printf("Scanning disk %s...\n", dev->name);
532 ret = efi_disk_add_dev(NULL, NULL, if_typename,
533 desc, desc->devnum, 0, 0, &disk);
534 if (ret == EFI_NOT_READY) {
535 printf("Disk %s not ready\n", dev->name);
539 printf("ERROR: failure to add disk device %s, r = %lu\n",
540 dev->name, ret & ~EFI_ERROR_MASK);
545 /* Partitions show up as block devices in EFI */
546 disks += efi_disk_create_partitions(
547 &disk->header, desc, if_typename,
548 desc->devnum, dev->name);
553 /* Search for all available disk devices */
554 for (if_type = 0; if_type < IF_TYPE_COUNT; if_type++) {
555 const struct blk_driver *cur_drvr;
556 const char *if_typename;
558 cur_drvr = blk_driver_lookup_type(if_type);
562 if_typename = cur_drvr->if_typename;
563 printf("Scanning disks on %s...\n", if_typename);
564 for (i = 0; i < 4; i++) {
565 struct blk_desc *desc;
566 char devname[32] = { 0 }; /* dp->str is u16[32] long */
568 desc = blk_get_devnum_by_type(if_type, i);
571 if (desc->type == DEV_TYPE_UNKNOWN)
574 snprintf(devname, sizeof(devname), "%s%d",
577 /* Add block device for the full device */
578 ret = efi_disk_add_dev(NULL, NULL, if_typename, desc,
580 if (ret == EFI_NOT_READY) {
581 printf("Disk %s not ready\n", devname);
585 printf("ERROR: failure to add disk device %s, r = %lu\n",
586 devname, ret & ~EFI_ERROR_MASK);
591 /* Partitions show up as block devices in EFI */
592 disks += efi_disk_create_partitions
593 (&disk->header, desc,
594 if_typename, i, devname);
598 printf("Found %d disks\n", disks);
604 * efi_disk_is_system_part() - check if handle refers to an EFI system partition
606 * @handle: handle of partition
608 * Return: true if handle refers to an EFI system partition
610 bool efi_disk_is_system_part(efi_handle_t handle)
612 struct efi_handler *handler;
613 struct efi_disk_obj *diskobj;
614 struct disk_partition info;
618 /* check if this is a block device */
619 ret = efi_search_protocol(handle, &efi_block_io_guid, &handler);
620 if (ret != EFI_SUCCESS)
623 diskobj = container_of(handle, struct efi_disk_obj, header);
625 r = part_get_info(diskobj->desc, diskobj->part, &info);
629 return !!(info.bootable & PART_EFI_SYSTEM_PARTITION);