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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 <fs.h>
13 #include <part.h>
14 #include <malloc.h>
15 
16 const efi_guid_t efi_block_io_guid = EFI_BLOCK_IO_PROTOCOL_GUID;
17 
18 /**
19  * struct efi_disk_obj - EFI disk object
20  *
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
27  * @part:	partition
28  * @volume:	simple file system protocol of the partition
29  * @offset:	offset into disk for simple partition
30  * @desc:	internal block device descriptor
31  */
32 struct efi_disk_obj {
33 	struct efi_object header;
34 	struct efi_block_io ops;
35 	const char *ifname;
36 	int dev_index;
37 	struct efi_block_io_media media;
38 	struct efi_device_path *dp;
39 	unsigned int part;
40 	struct efi_simple_file_system_protocol *volume;
41 	lbaint_t offset;
42 	struct blk_desc *desc;
43 };
44 
45 /**
46  * efi_disk_reset() - reset block device
47  *
48  * This function implements the Reset service of the EFI_BLOCK_IO_PROTOCOL.
49  *
50  * As U-Boot's block devices do not have a reset function simply return
51  * EFI_SUCCESS.
52  *
53  * See the Unified Extensible Firmware Interface (UEFI) specification for
54  * details.
55  *
56  * @this:			pointer to the BLOCK_IO_PROTOCOL
57  * @extended_verification:	extended verification
58  * Return:			status code
59  */
efi_disk_reset(struct efi_block_io * this,char extended_verification)60 static efi_status_t EFIAPI efi_disk_reset(struct efi_block_io *this,
61 			char extended_verification)
62 {
63 	EFI_ENTRY("%p, %x", this, extended_verification);
64 	return EFI_EXIT(EFI_SUCCESS);
65 }
66 
67 enum efi_disk_direction {
68 	EFI_DISK_READ,
69 	EFI_DISK_WRITE,
70 };
71 
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)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)
75 {
76 	struct efi_disk_obj *diskobj;
77 	struct blk_desc *desc;
78 	int blksz;
79 	int blocks;
80 	unsigned long n;
81 
82 	diskobj = container_of(this, struct efi_disk_obj, ops);
83 	desc = (struct blk_desc *) diskobj->desc;
84 	blksz = desc->blksz;
85 	blocks = buffer_size / blksz;
86 	lba += diskobj->offset;
87 
88 	EFI_PRINT("blocks=%x lba=%llx blksz=%x dir=%d\n",
89 		  blocks, lba, blksz, direction);
90 
91 	/* We only support full block access */
92 	if (buffer_size & (blksz - 1))
93 		return EFI_BAD_BUFFER_SIZE;
94 
95 	if (direction == EFI_DISK_READ)
96 		n = blk_dread(desc, lba, blocks, buffer);
97 	else
98 		n = blk_dwrite(desc, lba, blocks, buffer);
99 
100 	/* We don't do interrupts, so check for timers cooperatively */
101 	efi_timer_check();
102 
103 	EFI_PRINT("n=%lx blocks=%x\n", n, blocks);
104 
105 	if (n != blocks)
106 		return EFI_DEVICE_ERROR;
107 
108 	return EFI_SUCCESS;
109 }
110 
efi_disk_read_blocks(struct efi_block_io * this,u32 media_id,u64 lba,efi_uintn_t buffer_size,void * buffer)111 static efi_status_t EFIAPI efi_disk_read_blocks(struct efi_block_io *this,
112 			u32 media_id, u64 lba, efi_uintn_t buffer_size,
113 			void *buffer)
114 {
115 	void *real_buffer = buffer;
116 	efi_status_t r;
117 
118 	if (!this)
119 		return EFI_INVALID_PARAMETER;
120 	/* TODO: check for media changes */
121 	if (media_id != this->media->media_id)
122 		return EFI_MEDIA_CHANGED;
123 	if (!this->media->media_present)
124 		return EFI_NO_MEDIA;
125 	/* media->io_align is a power of 2 */
126 	if ((uintptr_t)buffer & (this->media->io_align - 1))
127 		return EFI_INVALID_PARAMETER;
128 	if (lba * this->media->block_size + buffer_size >
129 	    this->media->last_block * this->media->block_size)
130 		return EFI_INVALID_PARAMETER;
131 
132 #ifdef CONFIG_EFI_LOADER_BOUNCE_BUFFER
133 	if (buffer_size > EFI_LOADER_BOUNCE_BUFFER_SIZE) {
134 		r = efi_disk_read_blocks(this, media_id, lba,
135 			EFI_LOADER_BOUNCE_BUFFER_SIZE, buffer);
136 		if (r != EFI_SUCCESS)
137 			return r;
138 		return efi_disk_read_blocks(this, media_id, lba +
139 			EFI_LOADER_BOUNCE_BUFFER_SIZE / this->media->block_size,
140 			buffer_size - EFI_LOADER_BOUNCE_BUFFER_SIZE,
141 			buffer + EFI_LOADER_BOUNCE_BUFFER_SIZE);
142 	}
143 
144 	real_buffer = efi_bounce_buffer;
145 #endif
146 
147 	EFI_ENTRY("%p, %x, %llx, %zx, %p", this, media_id, lba,
148 		  buffer_size, buffer);
149 
150 	r = efi_disk_rw_blocks(this, media_id, lba, buffer_size, real_buffer,
151 			       EFI_DISK_READ);
152 
153 	/* Copy from bounce buffer to real buffer if necessary */
154 	if ((r == EFI_SUCCESS) && (real_buffer != buffer))
155 		memcpy(buffer, real_buffer, buffer_size);
156 
157 	return EFI_EXIT(r);
158 }
159 
efi_disk_write_blocks(struct efi_block_io * this,u32 media_id,u64 lba,efi_uintn_t buffer_size,void * buffer)160 static efi_status_t EFIAPI efi_disk_write_blocks(struct efi_block_io *this,
161 			u32 media_id, u64 lba, efi_uintn_t buffer_size,
162 			void *buffer)
163 {
164 	void *real_buffer = buffer;
165 	efi_status_t r;
166 
167 	if (!this)
168 		return EFI_INVALID_PARAMETER;
169 	if (this->media->read_only)
170 		return EFI_WRITE_PROTECTED;
171 	/* TODO: check for media changes */
172 	if (media_id != this->media->media_id)
173 		return EFI_MEDIA_CHANGED;
174 	if (!this->media->media_present)
175 		return EFI_NO_MEDIA;
176 	/* media->io_align is a power of 2 */
177 	if ((uintptr_t)buffer & (this->media->io_align - 1))
178 		return EFI_INVALID_PARAMETER;
179 	if (lba * this->media->block_size + buffer_size >
180 	    this->media->last_block * this->media->block_size)
181 		return EFI_INVALID_PARAMETER;
182 
183 #ifdef CONFIG_EFI_LOADER_BOUNCE_BUFFER
184 	if (buffer_size > EFI_LOADER_BOUNCE_BUFFER_SIZE) {
185 		r = efi_disk_write_blocks(this, media_id, lba,
186 			EFI_LOADER_BOUNCE_BUFFER_SIZE, buffer);
187 		if (r != EFI_SUCCESS)
188 			return r;
189 		return efi_disk_write_blocks(this, media_id, lba +
190 			EFI_LOADER_BOUNCE_BUFFER_SIZE / this->media->block_size,
191 			buffer_size - EFI_LOADER_BOUNCE_BUFFER_SIZE,
192 			buffer + EFI_LOADER_BOUNCE_BUFFER_SIZE);
193 	}
194 
195 	real_buffer = efi_bounce_buffer;
196 #endif
197 
198 	EFI_ENTRY("%p, %x, %llx, %zx, %p", this, media_id, lba,
199 		  buffer_size, buffer);
200 
201 	/* Populate bounce buffer if necessary */
202 	if (real_buffer != buffer)
203 		memcpy(real_buffer, buffer, buffer_size);
204 
205 	r = efi_disk_rw_blocks(this, media_id, lba, buffer_size, real_buffer,
206 			       EFI_DISK_WRITE);
207 
208 	return EFI_EXIT(r);
209 }
210 
efi_disk_flush_blocks(struct efi_block_io * this)211 static efi_status_t EFIAPI efi_disk_flush_blocks(struct efi_block_io *this)
212 {
213 	/* We always write synchronously */
214 	EFI_ENTRY("%p", this);
215 	return EFI_EXIT(EFI_SUCCESS);
216 }
217 
218 static const struct efi_block_io block_io_disk_template = {
219 	.reset = &efi_disk_reset,
220 	.read_blocks = &efi_disk_read_blocks,
221 	.write_blocks = &efi_disk_write_blocks,
222 	.flush_blocks = &efi_disk_flush_blocks,
223 };
224 
225 /*
226  * Get the simple file system protocol for a file device path.
227  *
228  * The full path provided is split into device part and into a file
229  * part. The device part is used to find the handle on which the
230  * simple file system protocol is installed.
231  *
232  * @full_path	device path including device and file
233  * @return	simple file system protocol
234  */
235 struct efi_simple_file_system_protocol *
efi_fs_from_path(struct efi_device_path * full_path)236 efi_fs_from_path(struct efi_device_path *full_path)
237 {
238 	struct efi_object *efiobj;
239 	struct efi_handler *handler;
240 	struct efi_device_path *device_path;
241 	struct efi_device_path *file_path;
242 	efi_status_t ret;
243 
244 	/* Split the path into a device part and a file part */
245 	ret = efi_dp_split_file_path(full_path, &device_path, &file_path);
246 	if (ret != EFI_SUCCESS)
247 		return NULL;
248 	efi_free_pool(file_path);
249 
250 	/* Get the EFI object for the partition */
251 	efiobj = efi_dp_find_obj(device_path, NULL);
252 	efi_free_pool(device_path);
253 	if (!efiobj)
254 		return NULL;
255 
256 	/* Find the simple file system protocol */
257 	ret = efi_search_protocol(efiobj, &efi_simple_file_system_protocol_guid,
258 				  &handler);
259 	if (ret != EFI_SUCCESS)
260 		return NULL;
261 
262 	/* Return the simple file system protocol for the partition */
263 	return handler->protocol_interface;
264 }
265 
266 /**
267  * efi_fs_exists() - check if a partition bears a file system
268  *
269  * @desc:	block device descriptor
270  * @part:	partition number
271  * Return:	1 if a file system exists on the partition
272  *		0 otherwise
273  */
efi_fs_exists(struct blk_desc * desc,int part)274 static int efi_fs_exists(struct blk_desc *desc, int part)
275 {
276 	if (fs_set_blk_dev_with_part(desc, part))
277 		return 0;
278 
279 	if (fs_get_type() == FS_TYPE_ANY)
280 		return 0;
281 
282 	fs_close();
283 
284 	return 1;
285 }
286 
287 /*
288  * Create a handle for a partition or disk
289  *
290  * @parent	parent handle
291  * @dp_parent	parent device path
292  * @if_typename interface name for block device
293  * @desc	internal block device
294  * @dev_index   device index for block device
295  * @offset	offset into disk for simple partitions
296  * @return	disk object
297  */
efi_disk_add_dev(efi_handle_t parent,struct efi_device_path * dp_parent,const char * if_typename,struct blk_desc * desc,int dev_index,lbaint_t offset,unsigned int part,struct efi_disk_obj ** disk)298 static efi_status_t efi_disk_add_dev(
299 				efi_handle_t parent,
300 				struct efi_device_path *dp_parent,
301 				const char *if_typename,
302 				struct blk_desc *desc,
303 				int dev_index,
304 				lbaint_t offset,
305 				unsigned int part,
306 				struct efi_disk_obj **disk)
307 {
308 	struct efi_disk_obj *diskobj;
309 	efi_status_t ret;
310 
311 	/* Don't add empty devices */
312 	if (!desc->lba)
313 		return EFI_NOT_READY;
314 
315 	diskobj = calloc(1, sizeof(*diskobj));
316 	if (!diskobj)
317 		return EFI_OUT_OF_RESOURCES;
318 
319 	/* Hook up to the device list */
320 	efi_add_handle(&diskobj->header);
321 
322 	/* Fill in object data */
323 	if (part) {
324 		struct efi_device_path *node = efi_dp_part_node(desc, part);
325 
326 		diskobj->dp = efi_dp_append_node(dp_parent, node);
327 		efi_free_pool(node);
328 	} else {
329 		diskobj->dp = efi_dp_from_part(desc, part);
330 	}
331 	diskobj->part = part;
332 	ret = efi_add_protocol(&diskobj->header, &efi_block_io_guid,
333 			       &diskobj->ops);
334 	if (ret != EFI_SUCCESS)
335 		return ret;
336 	ret = efi_add_protocol(&diskobj->header, &efi_guid_device_path,
337 			       diskobj->dp);
338 	if (ret != EFI_SUCCESS)
339 		return ret;
340 	/* partitions or whole disk without partitions */
341 	if ((part || desc->part_type == PART_TYPE_UNKNOWN) &&
342 	    efi_fs_exists(desc, part)) {
343 		diskobj->volume = efi_simple_file_system(desc, part,
344 							 diskobj->dp);
345 		ret = efi_add_protocol(&diskobj->header,
346 				       &efi_simple_file_system_protocol_guid,
347 				       diskobj->volume);
348 		if (ret != EFI_SUCCESS)
349 			return ret;
350 	}
351 	diskobj->ops = block_io_disk_template;
352 	diskobj->ifname = if_typename;
353 	diskobj->dev_index = dev_index;
354 	diskobj->offset = offset;
355 	diskobj->desc = desc;
356 
357 	/* Fill in EFI IO Media info (for read/write callbacks) */
358 	diskobj->media.removable_media = desc->removable;
359 	diskobj->media.media_present = 1;
360 	/*
361 	 * MediaID is just an arbitrary counter.
362 	 * We have to change it if the medium is removed or changed.
363 	 */
364 	diskobj->media.media_id = 1;
365 	diskobj->media.block_size = desc->blksz;
366 	diskobj->media.io_align = desc->blksz;
367 	diskobj->media.last_block = desc->lba - offset;
368 	if (part != 0)
369 		diskobj->media.logical_partition = 1;
370 	diskobj->ops.media = &diskobj->media;
371 	if (disk)
372 		*disk = diskobj;
373 	return EFI_SUCCESS;
374 }
375 
376 /*
377  * Create handles and protocols for the partitions of a block device
378  *
379  * @parent		handle of the parent disk
380  * @blk_desc		block device
381  * @if_typename		interface type
382  * @diskid		device number
383  * @pdevname		device name
384  * @return		number of partitions created
385  */
efi_disk_create_partitions(efi_handle_t parent,struct blk_desc * desc,const char * if_typename,int diskid,const char * pdevname)386 int efi_disk_create_partitions(efi_handle_t parent, struct blk_desc *desc,
387 			       const char *if_typename, int diskid,
388 			       const char *pdevname)
389 {
390 	int disks = 0;
391 	char devname[32] = { 0 }; /* dp->str is u16[32] long */
392 	disk_partition_t info;
393 	int part;
394 	struct efi_device_path *dp = NULL;
395 	efi_status_t ret;
396 	struct efi_handler *handler;
397 
398 	/* Get the device path of the parent */
399 	ret = efi_search_protocol(parent, &efi_guid_device_path, &handler);
400 	if (ret == EFI_SUCCESS)
401 		dp = handler->protocol_interface;
402 
403 	/* Add devices for each partition */
404 	for (part = 1; part <= MAX_SEARCH_PARTITIONS; part++) {
405 		if (part_get_info(desc, part, &info))
406 			continue;
407 		snprintf(devname, sizeof(devname), "%s:%d", pdevname,
408 			 part);
409 		ret = efi_disk_add_dev(parent, dp, if_typename, desc, diskid,
410 				       info.start, part, NULL);
411 		if (ret != EFI_SUCCESS) {
412 			printf("Adding partition %s failed\n", pdevname);
413 			continue;
414 		}
415 		disks++;
416 	}
417 
418 	return disks;
419 }
420 
421 /*
422  * U-Boot doesn't have a list of all online disk devices. So when running our
423  * EFI payload, we scan through all of the potentially available ones and
424  * store them in our object pool.
425  *
426  * TODO(sjg@chromium.org): Actually with CONFIG_BLK, U-Boot does have this.
427  * Consider converting the code to look up devices as needed. The EFI device
428  * could be a child of the UCLASS_BLK block device, perhaps.
429  *
430  * This gets called from do_bootefi_exec().
431  */
efi_disk_register(void)432 efi_status_t efi_disk_register(void)
433 {
434 	struct efi_disk_obj *disk;
435 	int disks = 0;
436 	efi_status_t ret;
437 #ifdef CONFIG_BLK
438 	struct udevice *dev;
439 
440 	for (uclass_first_device_check(UCLASS_BLK, &dev); dev;
441 	     uclass_next_device_check(&dev)) {
442 		struct blk_desc *desc = dev_get_uclass_platdata(dev);
443 		const char *if_typename = blk_get_if_type_name(desc->if_type);
444 
445 		/* Add block device for the full device */
446 		printf("Scanning disk %s...\n", dev->name);
447 		ret = efi_disk_add_dev(NULL, NULL, if_typename,
448 					desc, desc->devnum, 0, 0, &disk);
449 		if (ret == EFI_NOT_READY) {
450 			printf("Disk %s not ready\n", dev->name);
451 			continue;
452 		}
453 		if (ret) {
454 			printf("ERROR: failure to add disk device %s, r = %lu\n",
455 			       dev->name, ret & ~EFI_ERROR_MASK);
456 			return ret;
457 		}
458 		disks++;
459 
460 		/* Partitions show up as block devices in EFI */
461 		disks += efi_disk_create_partitions(
462 					&disk->header, desc, if_typename,
463 					desc->devnum, dev->name);
464 	}
465 #else
466 	int i, if_type;
467 
468 	/* Search for all available disk devices */
469 	for (if_type = 0; if_type < IF_TYPE_COUNT; if_type++) {
470 		const struct blk_driver *cur_drvr;
471 		const char *if_typename;
472 
473 		cur_drvr = blk_driver_lookup_type(if_type);
474 		if (!cur_drvr)
475 			continue;
476 
477 		if_typename = cur_drvr->if_typename;
478 		printf("Scanning disks on %s...\n", if_typename);
479 		for (i = 0; i < 4; i++) {
480 			struct blk_desc *desc;
481 			char devname[32] = { 0 }; /* dp->str is u16[32] long */
482 
483 			desc = blk_get_devnum_by_type(if_type, i);
484 			if (!desc)
485 				continue;
486 			if (desc->type == DEV_TYPE_UNKNOWN)
487 				continue;
488 
489 			snprintf(devname, sizeof(devname), "%s%d",
490 				 if_typename, i);
491 
492 			/* Add block device for the full device */
493 			ret = efi_disk_add_dev(NULL, NULL, if_typename, desc,
494 					       i, 0, 0, &disk);
495 			if (ret == EFI_NOT_READY) {
496 				printf("Disk %s not ready\n", devname);
497 				continue;
498 			}
499 			if (ret) {
500 				printf("ERROR: failure to add disk device %s, r = %lu\n",
501 				       devname, ret & ~EFI_ERROR_MASK);
502 				return ret;
503 			}
504 			disks++;
505 
506 			/* Partitions show up as block devices in EFI */
507 			disks += efi_disk_create_partitions
508 						(&disk->header, desc,
509 						 if_typename, i, devname);
510 		}
511 	}
512 #endif
513 	printf("Found %d disks\n", disks);
514 
515 	return EFI_SUCCESS;
516 }
517