xref: /openbmc/u-boot/lib/efi_loader/efi_disk.c (revision 4982f464)
1 /*
2  *  EFI application disk support
3  *
4  *  Copyright (c) 2016 Alexander Graf
5  *
6  *  SPDX-License-Identifier:     GPL-2.0+
7  */
8 
9 #include <common.h>
10 #include <blk.h>
11 #include <dm.h>
12 #include <efi_loader.h>
13 #include <inttypes.h>
14 #include <part.h>
15 #include <malloc.h>
16 
17 static const efi_guid_t efi_block_io_guid = BLOCK_IO_GUID;
18 
19 struct efi_disk_obj {
20 	/* Generic EFI object parent class data */
21 	struct efi_object parent;
22 	/* EFI Interface callback struct for block I/O */
23 	struct efi_block_io ops;
24 	/* U-Boot ifname for block device */
25 	const char *ifname;
26 	/* U-Boot dev_index for block device */
27 	int dev_index;
28 	/* EFI Interface Media descriptor struct, referenced by ops */
29 	struct efi_block_io_media media;
30 	/* EFI device path to this block device */
31 	struct efi_device_path_file_path *dp;
32 	/* Offset into disk for simple partitions */
33 	lbaint_t offset;
34 	/* Internal block device */
35 	const struct blk_desc *desc;
36 };
37 
38 static efi_status_t efi_disk_open_block(void *handle, efi_guid_t *protocol,
39 			void **protocol_interface, void *agent_handle,
40 			void *controller_handle, uint32_t attributes)
41 {
42 	struct efi_disk_obj *diskobj = handle;
43 
44 	*protocol_interface = &diskobj->ops;
45 
46 	return EFI_SUCCESS;
47 }
48 
49 static efi_status_t efi_disk_open_dp(void *handle, efi_guid_t *protocol,
50 			void **protocol_interface, void *agent_handle,
51 			void *controller_handle, uint32_t attributes)
52 {
53 	struct efi_disk_obj *diskobj = handle;
54 
55 	*protocol_interface = diskobj->dp;
56 
57 	return EFI_SUCCESS;
58 }
59 
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_DEVICE_ERROR);
65 }
66 
67 enum efi_disk_direction {
68 	EFI_DISK_READ,
69 	EFI_DISK_WRITE,
70 };
71 
72 static efi_status_t EFIAPI 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 	debug("EFI: %s:%d blocks=%x lba=%"PRIx64" blksz=%x dir=%d\n", __func__,
89 	      __LINE__, blocks, lba, blksz, direction);
90 
91 	/* We only support full block access */
92 	if (buffer_size & (blksz - 1))
93 		return EFI_EXIT(EFI_DEVICE_ERROR);
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 	debug("EFI: %s:%d n=%lx blocks=%x\n", __func__, __LINE__, n, blocks);
104 
105 	if (n != blocks)
106 		return EFI_EXIT(EFI_DEVICE_ERROR);
107 
108 	return EFI_EXIT(EFI_SUCCESS);
109 }
110 
111 static efi_status_t efi_disk_read_blocks(struct efi_block_io *this,
112 			u32 media_id, u64 lba, unsigned long buffer_size,
113 			void *buffer)
114 {
115 	void *real_buffer = buffer;
116 	efi_status_t r;
117 
118 #ifdef CONFIG_EFI_LOADER_BOUNCE_BUFFER
119 	if (buffer_size > EFI_LOADER_BOUNCE_BUFFER_SIZE) {
120 		r = efi_disk_read_blocks(this, media_id, lba,
121 			EFI_LOADER_BOUNCE_BUFFER_SIZE, buffer);
122 		if (r != EFI_SUCCESS)
123 			return r;
124 		return efi_disk_read_blocks(this, media_id, lba +
125 			EFI_LOADER_BOUNCE_BUFFER_SIZE / this->media->block_size,
126 			buffer_size - EFI_LOADER_BOUNCE_BUFFER_SIZE,
127 			buffer + EFI_LOADER_BOUNCE_BUFFER_SIZE);
128 	}
129 
130 	real_buffer = efi_bounce_buffer;
131 #endif
132 
133 	EFI_ENTRY("%p, %x, %"PRIx64", %lx, %p", this, media_id, lba,
134 		  buffer_size, buffer);
135 
136 	r = efi_disk_rw_blocks(this, media_id, lba, buffer_size, real_buffer,
137 			       EFI_DISK_READ);
138 
139 	/* Copy from bounce buffer to real buffer if necessary */
140 	if ((r == EFI_SUCCESS) && (real_buffer != buffer))
141 		memcpy(buffer, real_buffer, buffer_size);
142 
143 	return EFI_EXIT(r);
144 }
145 
146 static efi_status_t efi_disk_write_blocks(struct efi_block_io *this,
147 			u32 media_id, u64 lba, unsigned long buffer_size,
148 			void *buffer)
149 {
150 	void *real_buffer = buffer;
151 	efi_status_t r;
152 
153 #ifdef CONFIG_EFI_LOADER_BOUNCE_BUFFER
154 	if (buffer_size > EFI_LOADER_BOUNCE_BUFFER_SIZE) {
155 		r = efi_disk_write_blocks(this, media_id, lba,
156 			EFI_LOADER_BOUNCE_BUFFER_SIZE, buffer);
157 		if (r != EFI_SUCCESS)
158 			return r;
159 		return efi_disk_write_blocks(this, media_id, lba +
160 			EFI_LOADER_BOUNCE_BUFFER_SIZE / this->media->block_size,
161 			buffer_size - EFI_LOADER_BOUNCE_BUFFER_SIZE,
162 			buffer + EFI_LOADER_BOUNCE_BUFFER_SIZE);
163 	}
164 
165 	real_buffer = efi_bounce_buffer;
166 #endif
167 
168 	EFI_ENTRY("%p, %x, %"PRIx64", %lx, %p", this, media_id, lba,
169 		  buffer_size, buffer);
170 
171 	/* Populate bounce buffer if necessary */
172 	if (real_buffer != buffer)
173 		memcpy(real_buffer, buffer, buffer_size);
174 
175 	r = efi_disk_rw_blocks(this, media_id, lba, buffer_size, real_buffer,
176 			       EFI_DISK_WRITE);
177 
178 	return EFI_EXIT(r);
179 }
180 
181 static efi_status_t EFIAPI efi_disk_flush_blocks(struct efi_block_io *this)
182 {
183 	/* We always write synchronously */
184 	EFI_ENTRY("%p", this);
185 	return EFI_EXIT(EFI_SUCCESS);
186 }
187 
188 static const struct efi_block_io block_io_disk_template = {
189 	.reset = &efi_disk_reset,
190 	.read_blocks = &efi_disk_read_blocks,
191 	.write_blocks = &efi_disk_write_blocks,
192 	.flush_blocks = &efi_disk_flush_blocks,
193 };
194 
195 static void efi_disk_add_dev(const char *name,
196 			     const char *if_typename,
197 			     const struct blk_desc *desc,
198 			     int dev_index,
199 			     lbaint_t offset)
200 {
201 	struct efi_disk_obj *diskobj;
202 	struct efi_device_path_file_path *dp;
203 	int objlen = sizeof(*diskobj) + (sizeof(*dp) * 2);
204 
205 	/* Don't add empty devices */
206 	if (!desc->lba)
207 		return;
208 
209 	diskobj = calloc(1, objlen);
210 
211 	/* Fill in object data */
212 	diskobj->parent.protocols[0].guid = &efi_block_io_guid;
213 	diskobj->parent.protocols[0].open = efi_disk_open_block;
214 	diskobj->parent.protocols[1].guid = &efi_guid_device_path;
215 	diskobj->parent.protocols[1].open = efi_disk_open_dp;
216 	diskobj->parent.handle = diskobj;
217 	diskobj->ops = block_io_disk_template;
218 	diskobj->ifname = if_typename;
219 	diskobj->dev_index = dev_index;
220 	diskobj->offset = offset;
221 	diskobj->desc = desc;
222 
223 	/* Fill in EFI IO Media info (for read/write callbacks) */
224 	diskobj->media.removable_media = desc->removable;
225 	diskobj->media.media_present = 1;
226 	diskobj->media.block_size = desc->blksz;
227 	diskobj->media.io_align = desc->blksz;
228 	diskobj->media.last_block = desc->lba - offset;
229 	diskobj->ops.media = &diskobj->media;
230 
231 	/* Fill in device path */
232 	dp = (void*)&diskobj[1];
233 	diskobj->dp = dp;
234 	dp[0].dp.type = DEVICE_PATH_TYPE_MEDIA_DEVICE;
235 	dp[0].dp.sub_type = DEVICE_PATH_SUB_TYPE_FILE_PATH;
236 	dp[0].dp.length = sizeof(*dp);
237 	ascii2unicode(dp[0].str, name);
238 
239 	dp[1].dp.type = DEVICE_PATH_TYPE_END;
240 	dp[1].dp.sub_type = DEVICE_PATH_SUB_TYPE_END;
241 	dp[1].dp.length = sizeof(*dp);
242 
243 	/* Hook up to the device list */
244 	list_add_tail(&diskobj->parent.link, &efi_obj_list);
245 }
246 
247 static int efi_disk_create_eltorito(struct blk_desc *desc,
248 				    const char *if_typename,
249 				    int diskid,
250 				    const char *pdevname)
251 {
252 	int disks = 0;
253 #ifdef CONFIG_ISO_PARTITION
254 	char devname[32] = { 0 }; /* dp->str is u16[32] long */
255 	disk_partition_t info;
256 	int part = 1;
257 
258 	if (desc->part_type != PART_TYPE_ISO)
259 		return 0;
260 
261 	while (!part_get_info(desc, part, &info)) {
262 		snprintf(devname, sizeof(devname), "%s:%d", pdevname,
263 			 part);
264 		efi_disk_add_dev(devname, if_typename, desc, diskid,
265 				 info.start);
266 		part++;
267 		disks++;
268 	}
269 #endif
270 
271 	return disks;
272 }
273 
274 /*
275  * U-Boot doesn't have a list of all online disk devices. So when running our
276  * EFI payload, we scan through all of the potentially available ones and
277  * store them in our object pool.
278  *
279  * TODO(sjg@chromium.org): Actually with CONFIG_BLK, U-Boot does have this.
280  * Consider converting the code to look up devices as needed. The EFI device
281  * could be a child of the UCLASS_BLK block device, perhaps.
282  *
283  * This gets called from do_bootefi_exec().
284  */
285 int efi_disk_register(void)
286 {
287 	int disks = 0;
288 #ifdef CONFIG_BLK
289 	struct udevice *dev;
290 
291 	for (uclass_first_device(UCLASS_BLK, &dev);
292 	     dev;
293 	     uclass_next_device(&dev)) {
294 		struct blk_desc *desc = dev_get_uclass_platdata(dev);
295 		const char *if_typename = dev->driver->name;
296 
297 		printf("Scanning disk %s...\n", dev->name);
298 		efi_disk_add_dev(dev->name, if_typename, desc, desc->devnum, 0);
299 		disks++;
300 
301 		/*
302 		* El Torito images show up as block devices in an EFI world,
303 		* so let's create them here
304 		*/
305 		disks += efi_disk_create_eltorito(desc, if_typename,
306 						  desc->devnum, dev->name);
307 	}
308 #else
309 	int i, if_type;
310 
311 	/* Search for all available disk devices */
312 	for (if_type = 0; if_type < IF_TYPE_COUNT; if_type++) {
313 		const struct blk_driver *cur_drvr;
314 		const char *if_typename;
315 
316 		cur_drvr = blk_driver_lookup_type(if_type);
317 		if (!cur_drvr)
318 			continue;
319 
320 		if_typename = cur_drvr->if_typename;
321 		printf("Scanning disks on %s...\n", if_typename);
322 		for (i = 0; i < 4; i++) {
323 			struct blk_desc *desc;
324 			char devname[32] = { 0 }; /* dp->str is u16[32] long */
325 
326 			desc = blk_get_devnum_by_type(if_type, i);
327 			if (!desc)
328 				continue;
329 			if (desc->type == DEV_TYPE_UNKNOWN)
330 				continue;
331 
332 			snprintf(devname, sizeof(devname), "%s%d",
333 				 if_typename, i);
334 			efi_disk_add_dev(devname, if_typename, desc, i, 0);
335 			disks++;
336 
337 			/*
338 			 * El Torito images show up as block devices
339 			 * in an EFI world, so let's create them here
340 			 */
341 			disks += efi_disk_create_eltorito(desc, if_typename,
342 							  i, devname);
343 		}
344 	}
345 #endif
346 	printf("Found %d disks\n", disks);
347 
348 	return 0;
349 }
350