xref: /openbmc/u-boot/lib/efi_loader/efi_disk.c (revision 9702ec00)
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 	debug("EFI: %s:%d blocks=%x lba=%"PRIx64" blksz=%x dir=%d\n", __func__,
88 	      __LINE__, blocks, lba, blksz, direction);
89 
90 	/* We only support full block access */
91 	if (buffer_size & (blksz - 1))
92 		return EFI_EXIT(EFI_DEVICE_ERROR);
93 
94 	if (direction == EFI_DISK_READ)
95 		n = blk_dread(desc, lba, blocks, buffer);
96 	else
97 		n = blk_dwrite(desc, lba, blocks, buffer);
98 
99 	/* We don't do interrupts, so check for timers cooperatively */
100 	efi_timer_check();
101 
102 	debug("EFI: %s:%d n=%lx blocks=%x\n", __func__, __LINE__, n, blocks);
103 
104 	if (n != blocks)
105 		return EFI_EXIT(EFI_DEVICE_ERROR);
106 
107 	return EFI_EXIT(EFI_SUCCESS);
108 }
109 
110 static efi_status_t efi_disk_read_blocks(struct efi_block_io *this,
111 			u32 media_id, u64 lba, unsigned long buffer_size,
112 			void *buffer)
113 {
114 	void *real_buffer = buffer;
115 	efi_status_t r;
116 
117 #ifdef CONFIG_EFI_LOADER_BOUNCE_BUFFER
118 	if (buffer_size > EFI_LOADER_BOUNCE_BUFFER_SIZE) {
119 		r = efi_disk_read_blocks(this, media_id, lba,
120 			EFI_LOADER_BOUNCE_BUFFER_SIZE, buffer);
121 		if (r != EFI_SUCCESS)
122 			return r;
123 		return efi_disk_read_blocks(this, media_id, lba +
124 			EFI_LOADER_BOUNCE_BUFFER_SIZE / this->media->block_size,
125 			buffer_size - EFI_LOADER_BOUNCE_BUFFER_SIZE,
126 			buffer + EFI_LOADER_BOUNCE_BUFFER_SIZE);
127 	}
128 
129 	real_buffer = efi_bounce_buffer;
130 #endif
131 
132 	EFI_ENTRY("%p, %x, %"PRIx64", %lx, %p", this, media_id, lba,
133 		  buffer_size, buffer);
134 
135 	r = efi_disk_rw_blocks(this, media_id, lba, buffer_size, real_buffer,
136 			       EFI_DISK_READ);
137 
138 	/* Copy from bounce buffer to real buffer if necessary */
139 	if ((r == EFI_SUCCESS) && (real_buffer != buffer))
140 		memcpy(buffer, real_buffer, buffer_size);
141 
142 	return EFI_EXIT(r);
143 }
144 
145 static efi_status_t efi_disk_write_blocks(struct efi_block_io *this,
146 			u32 media_id, u64 lba, unsigned long buffer_size,
147 			void *buffer)
148 {
149 	void *real_buffer = buffer;
150 	efi_status_t r;
151 
152 #ifdef CONFIG_EFI_LOADER_BOUNCE_BUFFER
153 	if (buffer_size > EFI_LOADER_BOUNCE_BUFFER_SIZE) {
154 		r = efi_disk_write_blocks(this, media_id, lba,
155 			EFI_LOADER_BOUNCE_BUFFER_SIZE, buffer);
156 		if (r != EFI_SUCCESS)
157 			return r;
158 		return efi_disk_write_blocks(this, media_id, lba +
159 			EFI_LOADER_BOUNCE_BUFFER_SIZE / this->media->block_size,
160 			buffer_size - EFI_LOADER_BOUNCE_BUFFER_SIZE,
161 			buffer + EFI_LOADER_BOUNCE_BUFFER_SIZE);
162 	}
163 
164 	real_buffer = efi_bounce_buffer;
165 #endif
166 
167 	EFI_ENTRY("%p, %x, %"PRIx64", %lx, %p", this, media_id, lba,
168 		  buffer_size, buffer);
169 
170 	/* Populate bounce buffer if necessary */
171 	if (real_buffer != buffer)
172 		memcpy(real_buffer, buffer, buffer_size);
173 
174 	r = efi_disk_rw_blocks(this, media_id, lba, buffer_size, real_buffer,
175 			       EFI_DISK_WRITE);
176 
177 	return EFI_EXIT(r);
178 }
179 
180 static efi_status_t EFIAPI efi_disk_flush_blocks(struct efi_block_io *this)
181 {
182 	/* We always write synchronously */
183 	EFI_ENTRY("%p", this);
184 	return EFI_EXIT(EFI_SUCCESS);
185 }
186 
187 static const struct efi_block_io block_io_disk_template = {
188 	.reset = &efi_disk_reset,
189 	.read_blocks = &efi_disk_read_blocks,
190 	.write_blocks = &efi_disk_write_blocks,
191 	.flush_blocks = &efi_disk_flush_blocks,
192 };
193 
194 static void efi_disk_add_dev(const char *name,
195 			     const char *if_typename,
196 			     const struct blk_desc *desc,
197 			     int dev_index,
198 			     lbaint_t offset)
199 {
200 	struct efi_disk_obj *diskobj;
201 	struct efi_device_path_file_path *dp;
202 	int objlen = sizeof(*diskobj) + (sizeof(*dp) * 2);
203 
204 	diskobj = calloc(1, objlen);
205 
206 	/* Fill in object data */
207 	diskobj->parent.protocols[0].guid = &efi_block_io_guid;
208 	diskobj->parent.protocols[0].open = efi_disk_open_block;
209 	diskobj->parent.protocols[1].guid = &efi_guid_device_path;
210 	diskobj->parent.protocols[1].open = efi_disk_open_dp;
211 	diskobj->parent.handle = diskobj;
212 	diskobj->ops = block_io_disk_template;
213 	diskobj->ifname = if_typename;
214 	diskobj->dev_index = dev_index;
215 	diskobj->offset = offset;
216 
217 	/* Fill in EFI IO Media info (for read/write callbacks) */
218 	diskobj->media.removable_media = desc->removable;
219 	diskobj->media.media_present = 1;
220 	diskobj->media.block_size = desc->blksz;
221 	diskobj->media.io_align = desc->blksz;
222 	diskobj->media.last_block = desc->lba;
223 	diskobj->ops.media = &diskobj->media;
224 
225 	/* Fill in device path */
226 	dp = (void*)&diskobj[1];
227 	diskobj->dp = dp;
228 	dp[0].dp.type = DEVICE_PATH_TYPE_MEDIA_DEVICE;
229 	dp[0].dp.sub_type = DEVICE_PATH_SUB_TYPE_FILE_PATH;
230 	dp[0].dp.length = sizeof(*dp);
231 	ascii2unicode(dp[0].str, name);
232 
233 	dp[1].dp.type = DEVICE_PATH_TYPE_END;
234 	dp[1].dp.sub_type = DEVICE_PATH_SUB_TYPE_END;
235 	dp[1].dp.length = sizeof(*dp);
236 
237 	/* Hook up to the device list */
238 	list_add_tail(&diskobj->parent.link, &efi_obj_list);
239 }
240 
241 static int efi_disk_create_eltorito(struct blk_desc *desc,
242 				    const char *if_typename,
243 				    int diskid)
244 {
245 	int disks = 0;
246 #ifdef CONFIG_ISO_PARTITION
247 	char devname[32] = { 0 }; /* dp->str is u16[32] long */
248 	disk_partition_t info;
249 	int part = 1;
250 
251 	if (desc->part_type != PART_TYPE_ISO)
252 		return 0;
253 
254 	while (!part_get_info(desc, part, &info)) {
255 		snprintf(devname, sizeof(devname), "%s%d:%d", if_typename,
256 			 diskid, part);
257 		efi_disk_add_dev(devname, if_typename, desc, diskid,
258 				 info.start);
259 		part++;
260 		disks++;
261 	}
262 #endif
263 
264 	return disks;
265 }
266 
267 /*
268  * U-Boot doesn't have a list of all online disk devices. So when running our
269  * EFI payload, we scan through all of the potentially available ones and
270  * store them in our object pool.
271  *
272  * TODO(sjg@chromium.org): Actually with CONFIG_BLK, U-Boot does have this.
273  * Consider converting the code to look up devices as needed. The EFI device
274  * could be a child of the UCLASS_BLK block device, perhaps.
275  *
276  * This gets called from do_bootefi_exec().
277  */
278 int efi_disk_register(void)
279 {
280 	int disks = 0;
281 #ifdef CONFIG_BLK
282 	struct udevice *dev;
283 
284 	for (uclass_first_device(UCLASS_BLK, &dev);
285 	     dev;
286 	     uclass_next_device(&dev)) {
287 		struct blk_desc *desc = dev_get_uclass_platdata(dev);
288 		const char *if_typename = dev->driver->name;
289 
290 		printf("Scanning disk %s...\n", dev->name);
291 		efi_disk_add_dev(dev->name, if_typename, desc, desc->devnum, 0);
292 		disks++;
293 
294 		/*
295 		* El Torito images show up as block devices in an EFI world,
296 		* so let's create them here
297 		*/
298 		disks += efi_disk_create_eltorito(desc, if_typename,
299 						  desc->devnum);
300 	}
301 #else
302 	int i, if_type;
303 
304 	/* Search for all available disk devices */
305 	for (if_type = 0; if_type < IF_TYPE_COUNT; if_type++) {
306 		const struct blk_driver *cur_drvr;
307 		const char *if_typename;
308 
309 		cur_drvr = blk_driver_lookup_type(if_type);
310 		if (!cur_drvr)
311 			continue;
312 
313 		if_typename = cur_drvr->if_typename;
314 		printf("Scanning disks on %s...\n", if_typename);
315 		for (i = 0; i < 4; i++) {
316 			struct blk_desc *desc;
317 			char devname[32] = { 0 }; /* dp->str is u16[32] long */
318 
319 			desc = blk_get_devnum_by_type(if_type, i);
320 			if (!desc)
321 				continue;
322 			if (desc->type == DEV_TYPE_UNKNOWN)
323 				continue;
324 
325 			snprintf(devname, sizeof(devname), "%s%d",
326 				 if_typename, i);
327 			efi_disk_add_dev(devname, if_typename, desc, i, 0);
328 			disks++;
329 
330 			/*
331 			 * El Torito images show up as block devices
332 			 * in an EFI world, so let's create them here
333 			 */
334 			disks += efi_disk_create_eltorito(desc, if_typename, i);
335 		}
336 	}
337 #endif
338 	printf("Found %d disks\n", disks);
339 
340 	return 0;
341 }
342