xref: /openbmc/u-boot/lib/efi_loader/efi_disk.c (revision 82f29fd5)
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 = BLOCK_IO_GUID;
16 
17 struct efi_disk_obj {
18 	/* Generic EFI object parent class data */
19 	struct efi_object parent;
20 	/* EFI Interface callback struct for block I/O */
21 	struct efi_block_io ops;
22 	/* U-Boot ifname for block device */
23 	const char *ifname;
24 	/* U-Boot dev_index for block device */
25 	int dev_index;
26 	/* EFI Interface Media descriptor struct, referenced by ops */
27 	struct efi_block_io_media media;
28 	/* EFI device path to this block device */
29 	struct efi_device_path *dp;
30 	/* partition # */
31 	unsigned int part;
32 	/* handle to filesys proto (for partition objects) */
33 	struct efi_simple_file_system_protocol *volume;
34 	/* Offset into disk for simple partitions */
35 	lbaint_t offset;
36 	/* Internal block device */
37 	struct blk_desc *desc;
38 };
39 
40 static efi_status_t EFIAPI efi_disk_reset(struct efi_block_io *this,
41 			char extended_verification)
42 {
43 	EFI_ENTRY("%p, %x", this, extended_verification);
44 	return EFI_EXIT(EFI_DEVICE_ERROR);
45 }
46 
47 enum efi_disk_direction {
48 	EFI_DISK_READ,
49 	EFI_DISK_WRITE,
50 };
51 
52 static efi_status_t efi_disk_rw_blocks(struct efi_block_io *this,
53 			u32 media_id, u64 lba, unsigned long buffer_size,
54 			void *buffer, enum efi_disk_direction direction)
55 {
56 	struct efi_disk_obj *diskobj;
57 	struct blk_desc *desc;
58 	int blksz;
59 	int blocks;
60 	unsigned long n;
61 
62 	diskobj = container_of(this, struct efi_disk_obj, ops);
63 	desc = (struct blk_desc *) diskobj->desc;
64 	blksz = desc->blksz;
65 	blocks = buffer_size / blksz;
66 	lba += diskobj->offset;
67 
68 	debug("EFI: %s:%d blocks=%x lba=%llx blksz=%x dir=%d\n", __func__,
69 	      __LINE__, blocks, lba, blksz, direction);
70 
71 	/* We only support full block access */
72 	if (buffer_size & (blksz - 1))
73 		return EFI_DEVICE_ERROR;
74 
75 	if (direction == EFI_DISK_READ)
76 		n = blk_dread(desc, lba, blocks, buffer);
77 	else
78 		n = blk_dwrite(desc, lba, blocks, buffer);
79 
80 	/* We don't do interrupts, so check for timers cooperatively */
81 	efi_timer_check();
82 
83 	debug("EFI: %s:%d n=%lx blocks=%x\n", __func__, __LINE__, n, blocks);
84 
85 	if (n != blocks)
86 		return EFI_DEVICE_ERROR;
87 
88 	return EFI_SUCCESS;
89 }
90 
91 static efi_status_t EFIAPI efi_disk_read_blocks(struct efi_block_io *this,
92 			u32 media_id, u64 lba, efi_uintn_t buffer_size,
93 			void *buffer)
94 {
95 	void *real_buffer = buffer;
96 	efi_status_t r;
97 
98 #ifdef CONFIG_EFI_LOADER_BOUNCE_BUFFER
99 	if (buffer_size > EFI_LOADER_BOUNCE_BUFFER_SIZE) {
100 		r = efi_disk_read_blocks(this, media_id, lba,
101 			EFI_LOADER_BOUNCE_BUFFER_SIZE, buffer);
102 		if (r != EFI_SUCCESS)
103 			return r;
104 		return efi_disk_read_blocks(this, media_id, lba +
105 			EFI_LOADER_BOUNCE_BUFFER_SIZE / this->media->block_size,
106 			buffer_size - EFI_LOADER_BOUNCE_BUFFER_SIZE,
107 			buffer + EFI_LOADER_BOUNCE_BUFFER_SIZE);
108 	}
109 
110 	real_buffer = efi_bounce_buffer;
111 #endif
112 
113 	EFI_ENTRY("%p, %x, %llx, %zx, %p", this, media_id, lba,
114 		  buffer_size, buffer);
115 
116 	r = efi_disk_rw_blocks(this, media_id, lba, buffer_size, real_buffer,
117 			       EFI_DISK_READ);
118 
119 	/* Copy from bounce buffer to real buffer if necessary */
120 	if ((r == EFI_SUCCESS) && (real_buffer != buffer))
121 		memcpy(buffer, real_buffer, buffer_size);
122 
123 	return EFI_EXIT(r);
124 }
125 
126 static efi_status_t EFIAPI efi_disk_write_blocks(struct efi_block_io *this,
127 			u32 media_id, u64 lba, efi_uintn_t buffer_size,
128 			void *buffer)
129 {
130 	void *real_buffer = buffer;
131 	efi_status_t r;
132 
133 #ifdef CONFIG_EFI_LOADER_BOUNCE_BUFFER
134 	if (buffer_size > EFI_LOADER_BOUNCE_BUFFER_SIZE) {
135 		r = efi_disk_write_blocks(this, media_id, lba,
136 			EFI_LOADER_BOUNCE_BUFFER_SIZE, buffer);
137 		if (r != EFI_SUCCESS)
138 			return r;
139 		return efi_disk_write_blocks(this, media_id, lba +
140 			EFI_LOADER_BOUNCE_BUFFER_SIZE / this->media->block_size,
141 			buffer_size - EFI_LOADER_BOUNCE_BUFFER_SIZE,
142 			buffer + EFI_LOADER_BOUNCE_BUFFER_SIZE);
143 	}
144 
145 	real_buffer = efi_bounce_buffer;
146 #endif
147 
148 	EFI_ENTRY("%p, %x, %llx, %zx, %p", this, media_id, lba,
149 		  buffer_size, buffer);
150 
151 	/* Populate bounce buffer if necessary */
152 	if (real_buffer != buffer)
153 		memcpy(real_buffer, buffer, buffer_size);
154 
155 	r = efi_disk_rw_blocks(this, media_id, lba, buffer_size, real_buffer,
156 			       EFI_DISK_WRITE);
157 
158 	return EFI_EXIT(r);
159 }
160 
161 static efi_status_t EFIAPI efi_disk_flush_blocks(struct efi_block_io *this)
162 {
163 	/* We always write synchronously */
164 	EFI_ENTRY("%p", this);
165 	return EFI_EXIT(EFI_SUCCESS);
166 }
167 
168 static const struct efi_block_io block_io_disk_template = {
169 	.reset = &efi_disk_reset,
170 	.read_blocks = &efi_disk_read_blocks,
171 	.write_blocks = &efi_disk_write_blocks,
172 	.flush_blocks = &efi_disk_flush_blocks,
173 };
174 
175 /*
176  * Get the simple file system protocol for a file device path.
177  *
178  * The full path provided is split into device part and into a file
179  * part. The device part is used to find the handle on which the
180  * simple file system protocol is installed.
181  *
182  * @full_path	device path including device and file
183  * @return	simple file system protocol
184  */
185 struct efi_simple_file_system_protocol *
186 efi_fs_from_path(struct efi_device_path *full_path)
187 {
188 	struct efi_object *efiobj;
189 	struct efi_handler *handler;
190 	struct efi_device_path *device_path;
191 	struct efi_device_path *file_path;
192 	efi_status_t ret;
193 
194 	/* Split the path into a device part and a file part */
195 	ret = efi_dp_split_file_path(full_path, &device_path, &file_path);
196 	if (ret != EFI_SUCCESS)
197 		return NULL;
198 	efi_free_pool(file_path);
199 
200 	/* Get the EFI object for the partition */
201 	efiobj = efi_dp_find_obj(device_path, NULL);
202 	efi_free_pool(device_path);
203 	if (!efiobj)
204 		return NULL;
205 
206 	/* Find the simple file system protocol */
207 	ret = efi_search_protocol(efiobj, &efi_simple_file_system_protocol_guid,
208 				  &handler);
209 	if (ret != EFI_SUCCESS)
210 		return NULL;
211 
212 	/* Return the simple file system protocol for the partition */
213 	return handler->protocol_interface;
214 }
215 
216 /*
217  * Create a handle for a partition or disk
218  *
219  * @parent	parent handle
220  * @dp_parent	parent device path
221  * @if_typename interface name for block device
222  * @desc	internal block device
223  * @dev_index   device index for block device
224  * @offset	offset into disk for simple partitions
225  * @return	disk object
226  */
227 static efi_status_t efi_disk_add_dev(
228 				efi_handle_t parent,
229 				struct efi_device_path *dp_parent,
230 				const char *if_typename,
231 				struct blk_desc *desc,
232 				int dev_index,
233 				lbaint_t offset,
234 				unsigned int part,
235 				struct efi_disk_obj **disk)
236 {
237 	struct efi_disk_obj *diskobj;
238 	efi_status_t ret;
239 
240 	/* Don't add empty devices */
241 	if (!desc->lba)
242 		return EFI_NOT_READY;
243 
244 	diskobj = calloc(1, sizeof(*diskobj));
245 	if (!diskobj)
246 		return EFI_OUT_OF_RESOURCES;
247 
248 	/* Hook up to the device list */
249 	efi_add_handle(&diskobj->parent);
250 
251 	/* Fill in object data */
252 	if (part) {
253 		struct efi_device_path *node = efi_dp_part_node(desc, part);
254 
255 		diskobj->dp = efi_dp_append_node(dp_parent, node);
256 		efi_free_pool(node);
257 	} else {
258 		diskobj->dp = efi_dp_from_part(desc, part);
259 	}
260 	diskobj->part = part;
261 	ret = efi_add_protocol(diskobj->parent.handle, &efi_block_io_guid,
262 			       &diskobj->ops);
263 	if (ret != EFI_SUCCESS)
264 		return ret;
265 	ret = efi_add_protocol(diskobj->parent.handle, &efi_guid_device_path,
266 			       diskobj->dp);
267 	if (ret != EFI_SUCCESS)
268 		return ret;
269 	if (part >= 1) {
270 		diskobj->volume = efi_simple_file_system(desc, part,
271 							 diskobj->dp);
272 		ret = efi_add_protocol(diskobj->parent.handle,
273 				       &efi_simple_file_system_protocol_guid,
274 				       diskobj->volume);
275 		if (ret != EFI_SUCCESS)
276 			return ret;
277 	}
278 	diskobj->ops = block_io_disk_template;
279 	diskobj->ifname = if_typename;
280 	diskobj->dev_index = dev_index;
281 	diskobj->offset = offset;
282 	diskobj->desc = desc;
283 
284 	/* Fill in EFI IO Media info (for read/write callbacks) */
285 	diskobj->media.removable_media = desc->removable;
286 	diskobj->media.media_present = 1;
287 	diskobj->media.block_size = desc->blksz;
288 	diskobj->media.io_align = desc->blksz;
289 	diskobj->media.last_block = desc->lba - offset;
290 	if (part != 0)
291 		diskobj->media.logical_partition = 1;
292 	diskobj->ops.media = &diskobj->media;
293 	if (disk)
294 		*disk = diskobj;
295 	return EFI_SUCCESS;
296 }
297 
298 /*
299  * Create handles and protocols for the partitions of a block device
300  *
301  * @parent		handle of the parent disk
302  * @blk_desc		block device
303  * @if_typename		interface type
304  * @diskid		device number
305  * @pdevname		device name
306  * @return		number of partitions created
307  */
308 int efi_disk_create_partitions(efi_handle_t parent, struct blk_desc *desc,
309 			       const char *if_typename, int diskid,
310 			       const char *pdevname)
311 {
312 	int disks = 0;
313 	char devname[32] = { 0 }; /* dp->str is u16[32] long */
314 	disk_partition_t info;
315 	int part;
316 	struct efi_device_path *dp = NULL;
317 	efi_status_t ret;
318 	struct efi_handler *handler;
319 
320 	/* Get the device path of the parent */
321 	ret = efi_search_protocol(parent, &efi_guid_device_path, &handler);
322 	if (ret == EFI_SUCCESS)
323 		dp = handler->protocol_interface;
324 
325 	/* Add devices for each partition */
326 	for (part = 1; part <= MAX_SEARCH_PARTITIONS; part++) {
327 		if (part_get_info(desc, part, &info))
328 			continue;
329 		snprintf(devname, sizeof(devname), "%s:%d", pdevname,
330 			 part);
331 		ret = efi_disk_add_dev(parent, dp, if_typename, desc, diskid,
332 				       info.start, part, NULL);
333 		if (ret != EFI_SUCCESS) {
334 			printf("Adding partition %s failed\n", pdevname);
335 			continue;
336 		}
337 		disks++;
338 	}
339 
340 	return disks;
341 }
342 
343 /*
344  * U-Boot doesn't have a list of all online disk devices. So when running our
345  * EFI payload, we scan through all of the potentially available ones and
346  * store them in our object pool.
347  *
348  * TODO(sjg@chromium.org): Actually with CONFIG_BLK, U-Boot does have this.
349  * Consider converting the code to look up devices as needed. The EFI device
350  * could be a child of the UCLASS_BLK block device, perhaps.
351  *
352  * This gets called from do_bootefi_exec().
353  */
354 efi_status_t efi_disk_register(void)
355 {
356 	struct efi_disk_obj *disk;
357 	int disks = 0;
358 	efi_status_t ret;
359 #ifdef CONFIG_BLK
360 	struct udevice *dev;
361 
362 	for (uclass_first_device_check(UCLASS_BLK, &dev); dev;
363 	     uclass_next_device_check(&dev)) {
364 		struct blk_desc *desc = dev_get_uclass_platdata(dev);
365 		const char *if_typename = blk_get_if_type_name(desc->if_type);
366 
367 		/* Add block device for the full device */
368 		printf("Scanning disk %s...\n", dev->name);
369 		ret = efi_disk_add_dev(NULL, NULL, if_typename,
370 					desc, desc->devnum, 0, 0, &disk);
371 		if (ret == EFI_NOT_READY) {
372 			printf("Disk %s not ready\n", dev->name);
373 			continue;
374 		}
375 		if (ret) {
376 			printf("ERROR: failure to add disk device %s, r = %lu\n",
377 			       dev->name, ret & ~EFI_ERROR_MASK);
378 			return ret;
379 		}
380 		disks++;
381 
382 		/* Partitions show up as block devices in EFI */
383 		disks += efi_disk_create_partitions(
384 					disk->parent.handle, desc, if_typename,
385 					desc->devnum, dev->name);
386 	}
387 #else
388 	int i, if_type;
389 
390 	/* Search for all available disk devices */
391 	for (if_type = 0; if_type < IF_TYPE_COUNT; if_type++) {
392 		const struct blk_driver *cur_drvr;
393 		const char *if_typename;
394 
395 		cur_drvr = blk_driver_lookup_type(if_type);
396 		if (!cur_drvr)
397 			continue;
398 
399 		if_typename = cur_drvr->if_typename;
400 		printf("Scanning disks on %s...\n", if_typename);
401 		for (i = 0; i < 4; i++) {
402 			struct blk_desc *desc;
403 			char devname[32] = { 0 }; /* dp->str is u16[32] long */
404 
405 			desc = blk_get_devnum_by_type(if_type, i);
406 			if (!desc)
407 				continue;
408 			if (desc->type == DEV_TYPE_UNKNOWN)
409 				continue;
410 
411 			snprintf(devname, sizeof(devname), "%s%d",
412 				 if_typename, i);
413 
414 			/* Add block device for the full device */
415 			ret = efi_disk_add_dev(NULL, NULL, if_typename, desc,
416 					       i, 0, 0, &disk);
417 			if (ret == EFI_NOT_READY) {
418 				printf("Disk %s not ready\n", devname);
419 				continue;
420 			}
421 			if (ret) {
422 				printf("ERROR: failure to add disk device %s, r = %lu\n",
423 				       devname, ret & ~EFI_ERROR_MASK);
424 				return ret;
425 			}
426 			disks++;
427 
428 			/* Partitions show up as block devices in EFI */
429 			disks += efi_disk_create_partitions(
430 						disk->parent.handle, desc,
431 						if_typename, i, devname);
432 		}
433 	}
434 #endif
435 	printf("Found %d disks\n", disks);
436 
437 	return EFI_SUCCESS;
438 }
439