xref: /openbmc/u-boot/lib/efi_loader/efi_disk.c (revision ed4708aa)
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 };
35 
36 static efi_status_t efi_disk_open_block(void *handle, efi_guid_t *protocol,
37 			void **protocol_interface, void *agent_handle,
38 			void *controller_handle, uint32_t attributes)
39 {
40 	struct efi_disk_obj *diskobj = handle;
41 
42 	*protocol_interface = &diskobj->ops;
43 
44 	return EFI_SUCCESS;
45 }
46 
47 static efi_status_t efi_disk_open_dp(void *handle, efi_guid_t *protocol,
48 			void **protocol_interface, void *agent_handle,
49 			void *controller_handle, uint32_t attributes)
50 {
51 	struct efi_disk_obj *diskobj = handle;
52 
53 	*protocol_interface = diskobj->dp;
54 
55 	return EFI_SUCCESS;
56 }
57 
58 static efi_status_t EFIAPI efi_disk_reset(struct efi_block_io *this,
59 			char extended_verification)
60 {
61 	EFI_ENTRY("%p, %x", this, extended_verification);
62 	return EFI_EXIT(EFI_DEVICE_ERROR);
63 }
64 
65 enum efi_disk_direction {
66 	EFI_DISK_READ,
67 	EFI_DISK_WRITE,
68 };
69 
70 static efi_status_t EFIAPI efi_disk_rw_blocks(struct efi_block_io *this,
71 			u32 media_id, u64 lba, unsigned long buffer_size,
72 			void *buffer, enum efi_disk_direction direction)
73 {
74 	struct efi_disk_obj *diskobj;
75 	struct blk_desc *desc;
76 	int blksz;
77 	int blocks;
78 	unsigned long n;
79 
80 	diskobj = container_of(this, struct efi_disk_obj, ops);
81 	if (!(desc = blk_get_dev(diskobj->ifname, diskobj->dev_index)))
82 		return EFI_EXIT(EFI_DEVICE_ERROR);
83 	blksz = desc->blksz;
84 	blocks = buffer_size / blksz;
85 	lba += diskobj->offset;
86 
87 #ifdef DEBUG_EFI
88 	printf("EFI: %s:%d blocks=%x lba=%"PRIx64" blksz=%x dir=%d\n", __func__,
89 	       __LINE__, blocks, lba, blksz, direction);
90 #endif
91 
92 	/* We only support full block access */
93 	if (buffer_size & (blksz - 1))
94 		return EFI_EXIT(EFI_DEVICE_ERROR);
95 
96 	if (direction == EFI_DISK_READ)
97 		n = blk_dread(desc, lba, blocks, buffer);
98 	else
99 		n = blk_dwrite(desc, lba, blocks, buffer);
100 
101 	/* We don't do interrupts, so check for timers cooperatively */
102 	efi_timer_check();
103 
104 #ifdef DEBUG_EFI
105 	printf("EFI: %s:%d n=%lx blocks=%x\n", __func__, __LINE__, n, blocks);
106 #endif
107 	if (n != blocks)
108 		return EFI_EXIT(EFI_DEVICE_ERROR);
109 
110 	return EFI_EXIT(EFI_SUCCESS);
111 }
112 
113 static efi_status_t efi_disk_read_blocks(struct efi_block_io *this,
114 			u32 media_id, u64 lba, unsigned long buffer_size,
115 			void *buffer)
116 {
117 	void *real_buffer = buffer;
118 	efi_status_t r;
119 
120 #ifdef CONFIG_EFI_LOADER_BOUNCE_BUFFER
121 	if (buffer_size > EFI_LOADER_BOUNCE_BUFFER_SIZE) {
122 		r = efi_disk_read_blocks(this, media_id, lba,
123 			EFI_LOADER_BOUNCE_BUFFER_SIZE, buffer);
124 		if (r != EFI_SUCCESS)
125 			return r;
126 		return efi_disk_read_blocks(this, media_id, lba +
127 			EFI_LOADER_BOUNCE_BUFFER_SIZE / this->media->block_size,
128 			buffer_size - EFI_LOADER_BOUNCE_BUFFER_SIZE,
129 			buffer + EFI_LOADER_BOUNCE_BUFFER_SIZE);
130 	}
131 
132 	real_buffer = efi_bounce_buffer;
133 #endif
134 
135 	EFI_ENTRY("%p, %x, %"PRIx64", %lx, %p", this, media_id, lba,
136 		  buffer_size, buffer);
137 
138 	r = efi_disk_rw_blocks(this, media_id, lba, buffer_size, real_buffer,
139 			       EFI_DISK_READ);
140 
141 	/* Copy from bounce buffer to real buffer if necessary */
142 	if ((r == EFI_SUCCESS) && (real_buffer != buffer))
143 		memcpy(buffer, real_buffer, buffer_size);
144 
145 	return EFI_EXIT(r);
146 }
147 
148 static efi_status_t efi_disk_write_blocks(struct efi_block_io *this,
149 			u32 media_id, u64 lba, unsigned long buffer_size,
150 			void *buffer)
151 {
152 	void *real_buffer = buffer;
153 	efi_status_t r;
154 
155 #ifdef CONFIG_EFI_LOADER_BOUNCE_BUFFER
156 	if (buffer_size > EFI_LOADER_BOUNCE_BUFFER_SIZE) {
157 		r = efi_disk_write_blocks(this, media_id, lba,
158 			EFI_LOADER_BOUNCE_BUFFER_SIZE, buffer);
159 		if (r != EFI_SUCCESS)
160 			return r;
161 		return efi_disk_write_blocks(this, media_id, lba +
162 			EFI_LOADER_BOUNCE_BUFFER_SIZE / this->media->block_size,
163 			buffer_size - EFI_LOADER_BOUNCE_BUFFER_SIZE,
164 			buffer + EFI_LOADER_BOUNCE_BUFFER_SIZE);
165 	}
166 
167 	real_buffer = efi_bounce_buffer;
168 #endif
169 
170 	EFI_ENTRY("%p, %x, %"PRIx64", %lx, %p", this, media_id, lba,
171 		  buffer_size, buffer);
172 
173 	/* Populate bounce buffer if necessary */
174 	if (real_buffer != buffer)
175 		memcpy(real_buffer, buffer, buffer_size);
176 
177 	r = efi_disk_rw_blocks(this, media_id, lba, buffer_size, real_buffer,
178 			       EFI_DISK_WRITE);
179 
180 	return EFI_EXIT(r);
181 }
182 
183 static efi_status_t EFIAPI efi_disk_flush_blocks(struct efi_block_io *this)
184 {
185 	/* We always write synchronously */
186 	EFI_ENTRY("%p", this);
187 	return EFI_EXIT(EFI_SUCCESS);
188 }
189 
190 static const struct efi_block_io block_io_disk_template = {
191 	.reset = &efi_disk_reset,
192 	.read_blocks = &efi_disk_read_blocks,
193 	.write_blocks = &efi_disk_write_blocks,
194 	.flush_blocks = &efi_disk_flush_blocks,
195 };
196 
197 static void efi_disk_add_dev(const char *name,
198 			     const char *if_typename,
199 			     const struct blk_desc *desc,
200 			     int dev_index,
201 			     lbaint_t offset)
202 {
203 	struct efi_disk_obj *diskobj;
204 	struct efi_device_path_file_path *dp;
205 	int objlen = sizeof(*diskobj) + (sizeof(*dp) * 2);
206 
207 	diskobj = calloc(1, objlen);
208 
209 	/* Fill in object data */
210 	diskobj->parent.protocols[0].guid = &efi_block_io_guid;
211 	diskobj->parent.protocols[0].open = efi_disk_open_block;
212 	diskobj->parent.protocols[1].guid = &efi_guid_device_path;
213 	diskobj->parent.protocols[1].open = efi_disk_open_dp;
214 	diskobj->parent.handle = diskobj;
215 	diskobj->ops = block_io_disk_template;
216 	diskobj->ifname = if_typename;
217 	diskobj->dev_index = dev_index;
218 	diskobj->offset = offset;
219 
220 	/* Fill in EFI IO Media info (for read/write callbacks) */
221 	diskobj->media.removable_media = desc->removable;
222 	diskobj->media.media_present = 1;
223 	diskobj->media.block_size = desc->blksz;
224 	diskobj->media.io_align = desc->blksz;
225 	diskobj->media.last_block = desc->lba;
226 	diskobj->ops.media = &diskobj->media;
227 
228 	/* Fill in device path */
229 	dp = (void*)&diskobj[1];
230 	diskobj->dp = dp;
231 	dp[0].dp.type = DEVICE_PATH_TYPE_MEDIA_DEVICE;
232 	dp[0].dp.sub_type = DEVICE_PATH_SUB_TYPE_FILE_PATH;
233 	dp[0].dp.length = sizeof(*dp);
234 	ascii2unicode(dp[0].str, name);
235 
236 	dp[1].dp.type = DEVICE_PATH_TYPE_END;
237 	dp[1].dp.sub_type = DEVICE_PATH_SUB_TYPE_END;
238 	dp[1].dp.length = sizeof(*dp);
239 
240 	/* Hook up to the device list */
241 	list_add_tail(&diskobj->parent.link, &efi_obj_list);
242 }
243 
244 static int efi_disk_create_eltorito(struct blk_desc *desc,
245 				    const char *if_typename,
246 				    int diskid)
247 {
248 	int disks = 0;
249 #ifdef CONFIG_ISO_PARTITION
250 	char devname[32] = { 0 }; /* dp->str is u16[32] long */
251 	disk_partition_t info;
252 	int part = 1;
253 
254 	if (desc->part_type != PART_TYPE_ISO)
255 		return 0;
256 
257 	while (!part_get_info(desc, part, &info)) {
258 		snprintf(devname, sizeof(devname), "%s%d:%d", if_typename,
259 			 diskid, part);
260 		efi_disk_add_dev(devname, if_typename, desc, diskid,
261 				 info.start);
262 		part++;
263 		disks++;
264 	}
265 #endif
266 
267 	return disks;
268 }
269 
270 /*
271  * U-Boot doesn't have a list of all online disk devices. So when running our
272  * EFI payload, we scan through all of the potentially available ones and
273  * store them in our object pool.
274  *
275  * TODO(sjg@chromium.org): Actually with CONFIG_BLK, U-Boot does have this.
276  * Consider converting the code to look up devices as needed. The EFI device
277  * could be a child of the UCLASS_BLK block device, perhaps.
278  *
279  * This gets called from do_bootefi_exec().
280  */
281 int efi_disk_register(void)
282 {
283 	int disks = 0;
284 #ifdef CONFIG_BLK
285 	struct udevice *dev;
286 
287 	for (uclass_first_device(UCLASS_BLK, &dev);
288 	     dev;
289 	     uclass_next_device(&dev)) {
290 		struct blk_desc *desc = dev_get_uclass_platdata(dev);
291 		const char *if_typename = dev->driver->name;
292 
293 		printf("Scanning disk %s...\n", dev->name);
294 		efi_disk_add_dev(dev->name, if_typename, desc, desc->devnum, 0);
295 		disks++;
296 
297 		/*
298 		* El Torito images show up as block devices in an EFI world,
299 		* so let's create them here
300 		*/
301 		disks += efi_disk_create_eltorito(desc, if_typename,
302 						  desc->devnum);
303 	}
304 #else
305 	int i, if_type;
306 
307 	/* Search for all available disk devices */
308 	for (if_type = 0; if_type < IF_TYPE_COUNT; if_type++) {
309 		const struct blk_driver *cur_drvr;
310 		const char *if_typename;
311 
312 		cur_drvr = blk_driver_lookup_type(if_type);
313 		if (!cur_drvr)
314 			continue;
315 
316 		if_typename = cur_drvr->if_typename;
317 		printf("Scanning disks on %s...\n", if_typename);
318 		for (i = 0; i < 4; i++) {
319 			struct blk_desc *desc;
320 			char devname[32] = { 0 }; /* dp->str is u16[32] long */
321 
322 			desc = blk_get_devnum_by_type(if_type, i);
323 			if (!desc)
324 				continue;
325 			if (desc->type == DEV_TYPE_UNKNOWN)
326 				continue;
327 
328 			snprintf(devname, sizeof(devname), "%s%d",
329 				 if_typename, i);
330 			efi_disk_add_dev(devname, if_typename, desc, i, 0);
331 			disks++;
332 
333 			/*
334 			 * El Torito images show up as block devices
335 			 * in an EFI world, so let's create them here
336 			 */
337 			disks += efi_disk_create_eltorito(desc, if_typename, i);
338 		}
339 	}
340 #endif
341 	printf("Found %d disks\n", disks);
342 
343 	return 0;
344 }
345