1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  *  EFI application disk support
4  *
5  *  Copyright (c) 2016 Alexander Graf
6  */
7 
8 #define LOG_CATEGORY LOGC_EFI
9 
10 #include <common.h>
11 #include <blk.h>
12 #include <dm.h>
13 #include <dm/device-internal.h>
14 #include <dm/tag.h>
15 #include <event.h>
16 #include <efi_driver.h>
17 #include <efi_loader.h>
18 #include <fs.h>
19 #include <log.h>
20 #include <part.h>
21 #include <malloc.h>
22 
23 struct efi_system_partition efi_system_partition = {
24 	.uclass_id = UCLASS_INVALID,
25 };
26 
27 const efi_guid_t efi_block_io_guid = EFI_BLOCK_IO_PROTOCOL_GUID;
28 const efi_guid_t efi_system_partition_guid = PARTITION_SYSTEM_GUID;
29 
30 /**
31  * struct efi_disk_obj - EFI disk object
32  *
33  * @header:	EFI object header
34  * @ops:	EFI disk I/O protocol interface
35  * @dev_index:	device index of block device
36  * @media:	block I/O media information
37  * @dp:		device path to the block device
38  * @part:	partition
39  * @volume:	simple file system protocol of the partition
40  * @dev:	associated DM device
41  */
42 struct efi_disk_obj {
43 	struct efi_object header;
44 	struct efi_block_io ops;
45 	int dev_index;
46 	struct efi_block_io_media media;
47 	struct efi_device_path *dp;
48 	unsigned int part;
49 	struct efi_simple_file_system_protocol *volume;
50 };
51 
52 /**
53  * efi_disk_reset() - reset block device
54  *
55  * This function implements the Reset service of the EFI_BLOCK_IO_PROTOCOL.
56  *
57  * As U-Boot's block devices do not have a reset function simply return
58  * EFI_SUCCESS.
59  *
60  * See the Unified Extensible Firmware Interface (UEFI) specification for
61  * details.
62  *
63  * @this:			pointer to the BLOCK_IO_PROTOCOL
64  * @extended_verification:	extended verification
65  * Return:			status code
66  */
efi_disk_reset(struct efi_block_io * this,char extended_verification)67 static efi_status_t EFIAPI efi_disk_reset(struct efi_block_io *this,
68 			char extended_verification)
69 {
70 	EFI_ENTRY("%p, %x", this, extended_verification);
71 	return EFI_EXIT(EFI_SUCCESS);
72 }
73 
74 /**
75  * efi_disk_is_removable() - check if the device is removable media
76  * @handle:		efi object handle;
77  *
78  * Examine the device and determine if the device is a local block device
79  * and removable media.
80  *
81  * Return:		true if removable, false otherwise
82  */
efi_disk_is_removable(efi_handle_t handle)83 bool efi_disk_is_removable(efi_handle_t handle)
84 {
85 	struct efi_handler *handler;
86 	struct efi_block_io *io;
87 	efi_status_t ret;
88 
89 	ret = efi_search_protocol(handle, &efi_block_io_guid, &handler);
90 	if (ret != EFI_SUCCESS)
91 		return false;
92 
93 	io = handler->protocol_interface;
94 
95 	if (!io || !io->media)
96 		return false;
97 
98 	return (bool)io->media->removable_media;
99 }
100 
101 enum efi_disk_direction {
102 	EFI_DISK_READ,
103 	EFI_DISK_WRITE,
104 };
105 
efi_disk_rw_blocks(struct efi_block_io * this,u32 media_id,u64 lba,unsigned long buffer_size,void * buffer,enum efi_disk_direction direction)106 static efi_status_t efi_disk_rw_blocks(struct efi_block_io *this,
107 			u32 media_id, u64 lba, unsigned long buffer_size,
108 			void *buffer, enum efi_disk_direction direction)
109 {
110 	struct efi_disk_obj *diskobj;
111 	int blksz;
112 	int blocks;
113 	unsigned long n;
114 
115 	diskobj = container_of(this, struct efi_disk_obj, ops);
116 	blksz = diskobj->media.block_size;
117 	blocks = buffer_size / blksz;
118 
119 	EFI_PRINT("blocks=%x lba=%llx blksz=%x dir=%d\n",
120 		  blocks, lba, blksz, direction);
121 
122 	/* We only support full block access */
123 	if (buffer_size & (blksz - 1))
124 		return EFI_BAD_BUFFER_SIZE;
125 
126 	if (CONFIG_IS_ENABLED(PARTITIONS) &&
127 	    device_get_uclass_id(diskobj->header.dev) == UCLASS_PARTITION) {
128 		if (direction == EFI_DISK_READ)
129 			n = disk_blk_read(diskobj->header.dev, lba, blocks,
130 					  buffer);
131 		else
132 			n = disk_blk_write(diskobj->header.dev, lba, blocks,
133 					   buffer);
134 	} else {
135 		/* dev is a block device (UCLASS_BLK) */
136 		struct blk_desc *desc;
137 
138 		desc = dev_get_uclass_plat(diskobj->header.dev);
139 		if (direction == EFI_DISK_READ)
140 			n = blk_dread(desc, lba, blocks, buffer);
141 		else
142 			n = blk_dwrite(desc, lba, blocks, buffer);
143 	}
144 
145 	/* We don't do interrupts, so check for timers cooperatively */
146 	efi_timer_check();
147 
148 	EFI_PRINT("n=%lx blocks=%x\n", n, blocks);
149 
150 	if (n != blocks)
151 		return EFI_DEVICE_ERROR;
152 
153 	return EFI_SUCCESS;
154 }
155 
156 /**
157  * efi_disk_read_blocks() - reads blocks from device
158  *
159  * This function implements the ReadBlocks service of the EFI_BLOCK_IO_PROTOCOL.
160  *
161  * See the Unified Extensible Firmware Interface (UEFI) specification for
162  * details.
163  *
164  * @this:			pointer to the BLOCK_IO_PROTOCOL
165  * @media_id:			id of the medium to be read from
166  * @lba:			starting logical block for reading
167  * @buffer_size:		size of the read buffer
168  * @buffer:			pointer to the destination buffer
169  * Return:			status code
170  */
efi_disk_read_blocks(struct efi_block_io * this,u32 media_id,u64 lba,efi_uintn_t buffer_size,void * buffer)171 static efi_status_t EFIAPI efi_disk_read_blocks(struct efi_block_io *this,
172 			u32 media_id, u64 lba, efi_uintn_t buffer_size,
173 			void *buffer)
174 {
175 	void *real_buffer = buffer;
176 	efi_status_t r;
177 
178 	if (!this)
179 		return EFI_INVALID_PARAMETER;
180 	/* TODO: check for media changes */
181 	if (media_id != this->media->media_id)
182 		return EFI_MEDIA_CHANGED;
183 	if (!this->media->media_present)
184 		return EFI_NO_MEDIA;
185 	/* media->io_align is a power of 2 or 0 */
186 	if (this->media->io_align &&
187 	    (uintptr_t)buffer & (this->media->io_align - 1))
188 		return EFI_INVALID_PARAMETER;
189 	if (lba * this->media->block_size + buffer_size >
190 	    (this->media->last_block + 1) * this->media->block_size)
191 		return EFI_INVALID_PARAMETER;
192 
193 #ifdef CONFIG_EFI_LOADER_BOUNCE_BUFFER
194 	if (buffer_size > EFI_LOADER_BOUNCE_BUFFER_SIZE) {
195 		r = efi_disk_read_blocks(this, media_id, lba,
196 			EFI_LOADER_BOUNCE_BUFFER_SIZE, buffer);
197 		if (r != EFI_SUCCESS)
198 			return r;
199 		return efi_disk_read_blocks(this, media_id, lba +
200 			EFI_LOADER_BOUNCE_BUFFER_SIZE / this->media->block_size,
201 			buffer_size - EFI_LOADER_BOUNCE_BUFFER_SIZE,
202 			buffer + EFI_LOADER_BOUNCE_BUFFER_SIZE);
203 	}
204 
205 	real_buffer = efi_bounce_buffer;
206 #endif
207 
208 	EFI_ENTRY("%p, %x, %llx, %zx, %p", this, media_id, lba,
209 		  buffer_size, buffer);
210 
211 	r = efi_disk_rw_blocks(this, media_id, lba, buffer_size, real_buffer,
212 			       EFI_DISK_READ);
213 
214 	/* Copy from bounce buffer to real buffer if necessary */
215 	if ((r == EFI_SUCCESS) && (real_buffer != buffer))
216 		memcpy(buffer, real_buffer, buffer_size);
217 
218 	return EFI_EXIT(r);
219 }
220 
221 /**
222  * efi_disk_write_blocks() - writes blocks to device
223  *
224  * This function implements the WriteBlocks service of the
225  * EFI_BLOCK_IO_PROTOCOL.
226  *
227  * See the Unified Extensible Firmware Interface (UEFI) specification for
228  * details.
229  *
230  * @this:			pointer to the BLOCK_IO_PROTOCOL
231  * @media_id:			id of the medium to be written to
232  * @lba:			starting logical block for writing
233  * @buffer_size:		size of the write buffer
234  * @buffer:			pointer to the source buffer
235  * Return:			status code
236  */
efi_disk_write_blocks(struct efi_block_io * this,u32 media_id,u64 lba,efi_uintn_t buffer_size,void * buffer)237 static efi_status_t EFIAPI efi_disk_write_blocks(struct efi_block_io *this,
238 			u32 media_id, u64 lba, efi_uintn_t buffer_size,
239 			void *buffer)
240 {
241 	void *real_buffer = buffer;
242 	efi_status_t r;
243 
244 	if (!this)
245 		return EFI_INVALID_PARAMETER;
246 	if (this->media->read_only)
247 		return EFI_WRITE_PROTECTED;
248 	/* TODO: check for media changes */
249 	if (media_id != this->media->media_id)
250 		return EFI_MEDIA_CHANGED;
251 	if (!this->media->media_present)
252 		return EFI_NO_MEDIA;
253 	/* media->io_align is a power of 2 or 0 */
254 	if (this->media->io_align &&
255 	    (uintptr_t)buffer & (this->media->io_align - 1))
256 		return EFI_INVALID_PARAMETER;
257 	if (lba * this->media->block_size + buffer_size >
258 	    (this->media->last_block + 1) * this->media->block_size)
259 		return EFI_INVALID_PARAMETER;
260 
261 #ifdef CONFIG_EFI_LOADER_BOUNCE_BUFFER
262 	if (buffer_size > EFI_LOADER_BOUNCE_BUFFER_SIZE) {
263 		r = efi_disk_write_blocks(this, media_id, lba,
264 			EFI_LOADER_BOUNCE_BUFFER_SIZE, buffer);
265 		if (r != EFI_SUCCESS)
266 			return r;
267 		return efi_disk_write_blocks(this, media_id, lba +
268 			EFI_LOADER_BOUNCE_BUFFER_SIZE / this->media->block_size,
269 			buffer_size - EFI_LOADER_BOUNCE_BUFFER_SIZE,
270 			buffer + EFI_LOADER_BOUNCE_BUFFER_SIZE);
271 	}
272 
273 	real_buffer = efi_bounce_buffer;
274 #endif
275 
276 	EFI_ENTRY("%p, %x, %llx, %zx, %p", this, media_id, lba,
277 		  buffer_size, buffer);
278 
279 	/* Populate bounce buffer if necessary */
280 	if (real_buffer != buffer)
281 		memcpy(real_buffer, buffer, buffer_size);
282 
283 	r = efi_disk_rw_blocks(this, media_id, lba, buffer_size, real_buffer,
284 			       EFI_DISK_WRITE);
285 
286 	return EFI_EXIT(r);
287 }
288 
289 /**
290  * efi_disk_flush_blocks() - flushes modified data to the device
291  *
292  * This function implements the FlushBlocks service of the
293  * EFI_BLOCK_IO_PROTOCOL.
294  *
295  * As we always write synchronously nothing is done here.
296  *
297  * See the Unified Extensible Firmware Interface (UEFI) specification for
298  * details.
299  *
300  * @this:			pointer to the BLOCK_IO_PROTOCOL
301  * Return:			status code
302  */
efi_disk_flush_blocks(struct efi_block_io * this)303 static efi_status_t EFIAPI efi_disk_flush_blocks(struct efi_block_io *this)
304 {
305 	EFI_ENTRY("%p", this);
306 	return EFI_EXIT(EFI_SUCCESS);
307 }
308 
309 static const struct efi_block_io block_io_disk_template = {
310 	.reset = &efi_disk_reset,
311 	.read_blocks = &efi_disk_read_blocks,
312 	.write_blocks = &efi_disk_write_blocks,
313 	.flush_blocks = &efi_disk_flush_blocks,
314 };
315 
316 /**
317  * efi_fs_from_path() - retrieve simple file system protocol
318  *
319  * Gets the simple file system protocol for a file device path.
320  *
321  * The full path provided is split into device part and into a file
322  * part. The device part is used to find the handle on which the
323  * simple file system protocol is installed.
324  *
325  * @full_path:	device path including device and file
326  * Return:	simple file system protocol
327  */
328 struct efi_simple_file_system_protocol *
efi_fs_from_path(struct efi_device_path * full_path)329 efi_fs_from_path(struct efi_device_path *full_path)
330 {
331 	struct efi_object *efiobj;
332 	struct efi_handler *handler;
333 	struct efi_device_path *device_path;
334 	struct efi_device_path *file_path;
335 	efi_status_t ret;
336 
337 	/* Split the path into a device part and a file part */
338 	ret = efi_dp_split_file_path(full_path, &device_path, &file_path);
339 	if (ret != EFI_SUCCESS)
340 		return NULL;
341 	efi_free_pool(file_path);
342 
343 	/* Get the EFI object for the partition */
344 	efiobj = efi_dp_find_obj(device_path, NULL, NULL);
345 	efi_free_pool(device_path);
346 	if (!efiobj)
347 		return NULL;
348 
349 	/* Find the simple file system protocol */
350 	ret = efi_search_protocol(efiobj, &efi_simple_file_system_protocol_guid,
351 				  &handler);
352 	if (ret != EFI_SUCCESS)
353 		return NULL;
354 
355 	/* Return the simple file system protocol for the partition */
356 	return handler->protocol_interface;
357 }
358 
359 /**
360  * efi_fs_exists() - check if a partition bears a file system
361  *
362  * @desc:	block device descriptor
363  * @part:	partition number
364  * Return:	1 if a file system exists on the partition
365  *		0 otherwise
366  */
efi_fs_exists(struct blk_desc * desc,int part)367 static int efi_fs_exists(struct blk_desc *desc, int part)
368 {
369 	if (fs_set_blk_dev_with_part(desc, part))
370 		return 0;
371 
372 	if (fs_get_type() == FS_TYPE_ANY)
373 		return 0;
374 
375 	fs_close();
376 
377 	return 1;
378 }
379 
380 /**
381  * efi_disk_add_dev() - create a handle for a partition or disk
382  *
383  * @parent:		parent handle
384  * @dp_parent:		parent device path
385  * @desc:		internal block device
386  * @dev_index:		device index for block device
387  * @part_info:		partition info
388  * @part:		partition
389  * @disk:		pointer to receive the created handle
390  * @agent_handle:	handle of the EFI block driver
391  * Return:		disk object
392  */
efi_disk_add_dev(efi_handle_t parent,struct efi_device_path * dp_parent,struct blk_desc * desc,int dev_index,struct disk_partition * part_info,unsigned int part,struct efi_disk_obj ** disk,efi_handle_t agent_handle)393 static efi_status_t efi_disk_add_dev(
394 				efi_handle_t parent,
395 				struct efi_device_path *dp_parent,
396 				struct blk_desc *desc,
397 				int dev_index,
398 				struct disk_partition *part_info,
399 				unsigned int part,
400 				struct efi_disk_obj **disk,
401 				efi_handle_t agent_handle)
402 {
403 	struct efi_disk_obj *diskobj;
404 	struct efi_object *handle;
405 	const efi_guid_t *esp_guid = NULL;
406 	efi_status_t ret;
407 
408 	/* Don't add empty devices */
409 	if (!desc->lba)
410 		return EFI_NOT_READY;
411 
412 	diskobj = calloc(1, sizeof(*diskobj));
413 	if (!diskobj)
414 		return EFI_OUT_OF_RESOURCES;
415 
416 	/* Hook up to the device list */
417 	efi_add_handle(&diskobj->header);
418 
419 	/* Fill in object data */
420 	if (part_info) {
421 		struct efi_device_path *node = efi_dp_part_node(desc, part);
422 		struct efi_handler *handler;
423 		void *protocol_interface;
424 
425 		if (!node) {
426 			ret = EFI_OUT_OF_RESOURCES;
427 			log_debug("no node\n");
428 			goto error;
429 		}
430 
431 		/* Parent must expose EFI_BLOCK_IO_PROTOCOL */
432 		ret = efi_search_protocol(parent, &efi_block_io_guid, &handler);
433 		if (ret != EFI_SUCCESS) {
434 			log_debug("search failed\n");
435 			goto error;
436 		}
437 
438 		/*
439 		 * Link the partition (child controller) to the block device
440 		 * (controller).
441 		 */
442 		ret = efi_protocol_open(handler, &protocol_interface, NULL,
443 					&diskobj->header,
444 					EFI_OPEN_PROTOCOL_BY_CHILD_CONTROLLER);
445 		if (ret != EFI_SUCCESS) {
446 			log_debug("prot open failed\n");
447 			goto error;
448 		}
449 
450 		diskobj->dp = efi_dp_append_node(dp_parent, node);
451 		efi_free_pool(node);
452 		diskobj->media.last_block = part_info->size - 1;
453 		if (part_info->bootable & PART_EFI_SYSTEM_PARTITION)
454 			esp_guid = &efi_system_partition_guid;
455 	} else {
456 		diskobj->dp = efi_dp_from_part(desc, part);
457 		diskobj->media.last_block = desc->lba - 1;
458 	}
459 	diskobj->part = part;
460 
461 	/*
462 	 * Install the device path and the block IO protocol.
463 	 *
464 	 * InstallMultipleProtocolInterfaces() checks if the device path is
465 	 * already installed on an other handle and returns EFI_ALREADY_STARTED
466 	 * in this case.
467 	 */
468 	handle = &diskobj->header;
469 	ret = efi_install_multiple_protocol_interfaces(
470 					&handle,
471 					&efi_guid_device_path, diskobj->dp,
472 					&efi_block_io_guid, &diskobj->ops,
473 					/*
474 					 * esp_guid must be last entry as it
475 					 * can be NULL. Its interface is NULL.
476 					 */
477 					esp_guid, NULL,
478 					NULL);
479 	if (ret != EFI_SUCCESS) {
480 		log_debug("install failed %lx\n", ret);
481 		goto error;
482 	}
483 
484 	/*
485 	 * On partitions or whole disks without partitions install the
486 	 * simple file system protocol if a file system is available.
487 	 */
488 	if ((part || desc->part_type == PART_TYPE_UNKNOWN) &&
489 	    efi_fs_exists(desc, part)) {
490 		diskobj->volume = efi_simple_file_system(desc, part,
491 							 diskobj->dp);
492 		ret = efi_add_protocol(&diskobj->header,
493 				       &efi_simple_file_system_protocol_guid,
494 				       diskobj->volume);
495 		if (ret != EFI_SUCCESS) {
496 			log_debug("simple FS failed\n");
497 			return ret;
498 		}
499 	}
500 	diskobj->ops = block_io_disk_template;
501 	diskobj->dev_index = dev_index;
502 
503 	/* Fill in EFI IO Media info (for read/write callbacks) */
504 	diskobj->media.removable_media = desc->removable;
505 	diskobj->media.media_present = 1;
506 	/*
507 	 * MediaID is just an arbitrary counter.
508 	 * We have to change it if the medium is removed or changed.
509 	 */
510 	diskobj->media.media_id = 1;
511 	diskobj->media.block_size = desc->blksz;
512 	diskobj->media.io_align = desc->blksz;
513 	if (part)
514 		diskobj->media.logical_partition = 1;
515 	diskobj->ops.media = &diskobj->media;
516 	if (disk)
517 		*disk = diskobj;
518 
519 	EFI_PRINT("BlockIO: part %u, present %d, logical %d, removable %d"
520 		  ", last_block %llu\n",
521 		  diskobj->part,
522 		  diskobj->media.media_present,
523 		  diskobj->media.logical_partition,
524 		  diskobj->media.removable_media,
525 		  diskobj->media.last_block);
526 
527 	/* Store first EFI system partition */
528 	if (part && efi_system_partition.uclass_id == UCLASS_INVALID) {
529 		if (part_info->bootable & PART_EFI_SYSTEM_PARTITION) {
530 			efi_system_partition.uclass_id = desc->uclass_id;
531 			efi_system_partition.devnum = desc->devnum;
532 			efi_system_partition.part = part;
533 			EFI_PRINT("EFI system partition: %s %x:%x\n",
534 				  blk_get_uclass_name(desc->uclass_id),
535 				  desc->devnum, part);
536 		}
537 	}
538 	return EFI_SUCCESS;
539 error:
540 	efi_delete_handle(&diskobj->header);
541 	return ret;
542 }
543 
544 /**
545  * efi_disk_create_raw() - create a handle for a whole raw disk
546  *
547  * @dev:		udevice (UCLASS_BLK)
548  * @agent_handle:	handle of the EFI block driver
549  *
550  * Create an efi_disk object which is associated with @dev.
551  * The type of @dev must be UCLASS_BLK.
552  *
553  * Return:		0 on success, -1 otherwise
554  */
efi_disk_create_raw(struct udevice * dev,efi_handle_t agent_handle)555 static int efi_disk_create_raw(struct udevice *dev, efi_handle_t agent_handle)
556 {
557 	struct efi_disk_obj *disk;
558 	struct blk_desc *desc;
559 	int diskid;
560 	efi_status_t ret;
561 
562 	desc = dev_get_uclass_plat(dev);
563 	diskid = desc->devnum;
564 
565 	ret = efi_disk_add_dev(NULL, NULL, desc,
566 			       diskid, NULL, 0, &disk, agent_handle);
567 	if (ret != EFI_SUCCESS) {
568 		if (ret == EFI_NOT_READY) {
569 			log_notice("Disk %s not ready\n", dev->name);
570 			ret = -EBUSY;
571 		} else {
572 			log_err("Adding disk for %s failed (err=%ld/%#lx)\n", dev->name, ret, ret);
573 			ret = -ENOENT;
574 		}
575 
576 		return ret;
577 	}
578 	if (efi_link_dev(&disk->header, dev)) {
579 		efi_free_pool(disk->dp);
580 		efi_delete_handle(&disk->header);
581 
582 		return -EINVAL;
583 	}
584 
585 	return 0;
586 }
587 
588 /**
589  * efi_disk_create_part() - create a handle for a disk partition
590  *
591  * @dev:		udevice (UCLASS_PARTITION)
592  * @agent_handle:	handle of the EFI block driver
593  *
594  * Create an efi_disk object which is associated with @dev.
595  * The type of @dev must be UCLASS_PARTITION.
596  *
597  * Return:		0 on success, -1 otherwise
598  */
efi_disk_create_part(struct udevice * dev,efi_handle_t agent_handle)599 static int efi_disk_create_part(struct udevice *dev, efi_handle_t agent_handle)
600 {
601 	efi_handle_t parent;
602 	struct blk_desc *desc;
603 	struct disk_part *part_data;
604 	struct disk_partition *info;
605 	unsigned int part;
606 	int diskid;
607 	struct efi_handler *handler;
608 	struct efi_device_path *dp_parent;
609 	struct efi_disk_obj *disk;
610 	efi_status_t ret;
611 
612 	if (dev_tag_get_ptr(dev_get_parent(dev), DM_TAG_EFI, (void **)&parent))
613 		return -1;
614 
615 	desc = dev_get_uclass_plat(dev_get_parent(dev));
616 	diskid = desc->devnum;
617 
618 	part_data = dev_get_uclass_plat(dev);
619 	part = part_data->partnum;
620 	info = &part_data->gpt_part_info;
621 
622 	ret = efi_search_protocol(parent, &efi_guid_device_path, &handler);
623 	if (ret != EFI_SUCCESS)
624 		return -1;
625 	dp_parent = (struct efi_device_path *)handler->protocol_interface;
626 
627 	ret = efi_disk_add_dev(parent, dp_parent, desc, diskid,
628 			       info, part, &disk, agent_handle);
629 	if (ret != EFI_SUCCESS) {
630 		log_err("Adding partition for %s failed\n", dev->name);
631 		return -1;
632 	}
633 	if (efi_link_dev(&disk->header, dev)) {
634 		efi_free_pool(disk->dp);
635 		efi_delete_handle(&disk->header);
636 
637 		return -1;
638 	}
639 
640 	return 0;
641 }
642 
643 /**
644  * efi_disk_probe() - create efi_disk objects for a block device
645  *
646  * @ctx:	event context - driver binding protocol
647  * @event:	EV_PM_POST_PROBE event
648  *
649  * Create efi_disk objects for partitions as well as a raw disk
650  * which is associated with @dev.
651  * The type of @dev must be UCLASS_BLK.
652  * This function is expected to be called at EV_PM_POST_PROBE.
653  *
654  * Return:	0 on success, -1 otherwise
655  */
efi_disk_probe(void * ctx,struct event * event)656 int efi_disk_probe(void *ctx, struct event *event)
657 {
658 	struct udevice *dev;
659 	enum uclass_id id;
660 	struct blk_desc *desc;
661 	struct udevice *child;
662 	struct efi_driver_binding_extended_protocol *db_prot = ctx;
663 	efi_handle_t agent_handle = db_prot->bp.driver_binding_handle;
664 	int ret;
665 
666 	dev = event->data.dm.dev;
667 	id = device_get_uclass_id(dev);
668 
669 	/* We won't support partitions in a partition */
670 	if (id != UCLASS_BLK)
671 		return 0;
672 
673 	/*
674 	 * Avoid creating duplicated objects now that efi_driver
675 	 * has already created an efi_disk at this moment.
676 	 */
677 	desc = dev_get_uclass_plat(dev);
678 	if (desc->uclass_id != UCLASS_EFI_LOADER) {
679 		ret = efi_disk_create_raw(dev, agent_handle);
680 		if (ret)
681 			return -1;
682 	}
683 
684 	device_foreach_child(child, dev) {
685 		ret = efi_disk_create_part(child, agent_handle);
686 		if (ret)
687 			return -1;
688 	}
689 
690 	return 0;
691 }
692 
693 /**
694  * efi_disk_remove - delete an efi_disk object for a block device or partition
695  *
696  * @ctx:	event context: driver binding protocol
697  * @event:	EV_PM_PRE_REMOVE event
698  *
699  * Delete an efi_disk object which is associated with the UCLASS_BLK or
700  * UCLASS_PARTITION device for which the EV_PM_PRE_REMOVE event is raised.
701  *
702  * Return:	0 on success, -1 otherwise
703  */
efi_disk_remove(void * ctx,struct event * event)704 int efi_disk_remove(void *ctx, struct event *event)
705 {
706 	enum uclass_id id;
707 	struct udevice *dev = event->data.dm.dev;
708 	efi_handle_t handle;
709 	struct blk_desc *desc;
710 	struct efi_disk_obj *diskobj = NULL;
711 
712 	if (dev_tag_get_ptr(dev, DM_TAG_EFI, (void **)&handle))
713 		return 0;
714 
715 	id = device_get_uclass_id(dev);
716 	switch (id) {
717 	case UCLASS_BLK:
718 		desc = dev_get_uclass_plat(dev);
719 		if (desc && desc->uclass_id != UCLASS_EFI_LOADER)
720 			diskobj = container_of(handle, struct efi_disk_obj,
721 					       header);
722 		break;
723 	case UCLASS_PARTITION:
724 		diskobj = container_of(handle, struct efi_disk_obj, header);
725 		break;
726 	default:
727 		return 0;
728 	}
729 
730 	if (diskobj)
731 		efi_free_pool(diskobj->dp);
732 
733 	efi_delete_handle(handle);
734 	dev_tag_del(dev, DM_TAG_EFI);
735 
736 	return 0;
737 }
738 
739 /**
740  * efi_disk_get_device_name() - get U-Boot device name associated with EFI handle
741  *
742  * @handle:	pointer to the EFI handle
743  * @buf:	pointer to the buffer to store the string
744  * @size:	size of buffer
745  * Return:	status code
746  */
efi_disk_get_device_name(const efi_handle_t handle,char * buf,int size)747 efi_status_t efi_disk_get_device_name(const efi_handle_t handle, char *buf, int size)
748 {
749 	int count;
750 	int diskid;
751 	enum uclass_id id;
752 	unsigned int part;
753 	struct udevice *dev;
754 	struct blk_desc *desc;
755 	const char *if_typename;
756 	bool is_partition = false;
757 	struct disk_part *part_data;
758 
759 	if (!handle || !buf || !size)
760 		return EFI_INVALID_PARAMETER;
761 
762 	dev = handle->dev;
763 	id = device_get_uclass_id(dev);
764 	if (id == UCLASS_BLK) {
765 		desc = dev_get_uclass_plat(dev);
766 	} else if (id == UCLASS_PARTITION) {
767 		desc = dev_get_uclass_plat(dev_get_parent(dev));
768 		is_partition = true;
769 	} else {
770 		return EFI_INVALID_PARAMETER;
771 	}
772 	if_typename = blk_get_uclass_name(desc->uclass_id);
773 	diskid = desc->devnum;
774 
775 	if (is_partition) {
776 		part_data = dev_get_uclass_plat(dev);
777 		part = part_data->partnum;
778 		count = snprintf(buf, size, "%s %d:%u", if_typename, diskid,
779 				 part);
780 	} else {
781 		count = snprintf(buf, size, "%s %d", if_typename, diskid);
782 	}
783 
784 	if (count < 0 || (count + 1) > size)
785 		return EFI_INVALID_PARAMETER;
786 
787 	return EFI_SUCCESS;
788 }
789 
790 /**
791  * efi_disks_register() - ensure all block devices are available in UEFI
792  *
793  * The function probes all block devices. As we store UEFI variables on the
794  * EFI system partition this function has to be called before enabling
795  * variable services.
796  */
efi_disks_register(void)797 efi_status_t efi_disks_register(void)
798 {
799 	struct udevice *dev;
800 
801 	uclass_foreach_dev_probe(UCLASS_BLK, dev) {
802 	}
803 
804 	return EFI_SUCCESS;
805 }
806