xref: /openbmc/u-boot/lib/efi_loader/efi_disk.c (revision ae4dc15d)
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 <efi_loader.h>
11 #include <inttypes.h>
12 #include <part.h>
13 #include <malloc.h>
14 
15 static 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_file_path *dp;
30 	/* Offset into disk for simple partitions */
31 	lbaint_t offset;
32 };
33 
34 static efi_status_t efi_disk_open_block(void *handle, efi_guid_t *protocol,
35 			void **protocol_interface, void *agent_handle,
36 			void *controller_handle, uint32_t attributes)
37 {
38 	struct efi_disk_obj *diskobj = handle;
39 
40 	*protocol_interface = &diskobj->ops;
41 
42 	return EFI_SUCCESS;
43 }
44 
45 static efi_status_t efi_disk_open_dp(void *handle, efi_guid_t *protocol,
46 			void **protocol_interface, void *agent_handle,
47 			void *controller_handle, uint32_t attributes)
48 {
49 	struct efi_disk_obj *diskobj = handle;
50 
51 	*protocol_interface = diskobj->dp;
52 
53 	return EFI_SUCCESS;
54 }
55 
56 static efi_status_t EFIAPI efi_disk_reset(struct efi_block_io *this,
57 			char extended_verification)
58 {
59 	EFI_ENTRY("%p, %x", this, extended_verification);
60 	return EFI_EXIT(EFI_DEVICE_ERROR);
61 }
62 
63 enum efi_disk_direction {
64 	EFI_DISK_READ,
65 	EFI_DISK_WRITE,
66 };
67 
68 static efi_status_t EFIAPI efi_disk_rw_blocks(struct efi_block_io *this,
69 			u32 media_id, u64 lba, unsigned long buffer_size,
70 			void *buffer, enum efi_disk_direction direction)
71 {
72 	struct efi_disk_obj *diskobj;
73 	struct blk_desc *desc;
74 	int blksz;
75 	int blocks;
76 	unsigned long n;
77 
78 	EFI_ENTRY("%p, %x, %"PRIx64", %lx, %p", this, media_id, lba,
79 		  buffer_size, buffer);
80 
81 	diskobj = container_of(this, struct efi_disk_obj, ops);
82 	if (!(desc = blk_get_dev(diskobj->ifname, diskobj->dev_index)))
83 		return EFI_EXIT(EFI_DEVICE_ERROR);
84 	blksz = desc->blksz;
85 	blocks = buffer_size / blksz;
86 	lba += diskobj->offset;
87 
88 #ifdef DEBUG_EFI
89 	printf("EFI: %s:%d blocks=%x lba=%"PRIx64" blksz=%x dir=%d\n", __func__,
90 	       __LINE__, blocks, lba, blksz, direction);
91 #endif
92 
93 	/* We only support full block access */
94 	if (buffer_size & (blksz - 1))
95 		return EFI_EXIT(EFI_DEVICE_ERROR);
96 
97 	if (direction == EFI_DISK_READ)
98 		n = desc->block_read(desc, lba, blocks, buffer);
99 	else
100 		n = desc->block_write(desc, lba, blocks, buffer);
101 
102 	/* We don't do interrupts, so check for timers cooperatively */
103 	efi_timer_check();
104 
105 #ifdef DEBUG_EFI
106 	printf("EFI: %s:%d n=%lx blocks=%x\n", __func__, __LINE__, n, blocks);
107 #endif
108 	if (n != blocks)
109 		return EFI_EXIT(EFI_DEVICE_ERROR);
110 
111 	return EFI_EXIT(EFI_SUCCESS);
112 }
113 
114 static efi_status_t efi_disk_read_blocks(struct efi_block_io *this,
115 			u32 media_id, u64 lba, unsigned long buffer_size,
116 			void *buffer)
117 {
118 	return efi_disk_rw_blocks(this, media_id, lba, buffer_size, buffer,
119 				  EFI_DISK_READ);
120 }
121 
122 static efi_status_t efi_disk_write_blocks(struct efi_block_io *this,
123 			u32 media_id, u64 lba, unsigned long buffer_size,
124 			void *buffer)
125 {
126 	return efi_disk_rw_blocks(this, media_id, lba, buffer_size, buffer,
127 				  EFI_DISK_WRITE);
128 }
129 
130 static efi_status_t EFIAPI efi_disk_flush_blocks(struct efi_block_io *this)
131 {
132 	/* We always write synchronously */
133 	EFI_ENTRY("%p", this);
134 	return EFI_EXIT(EFI_SUCCESS);
135 }
136 
137 static const struct efi_block_io block_io_disk_template = {
138 	.reset = &efi_disk_reset,
139 	.read_blocks = &efi_disk_read_blocks,
140 	.write_blocks = &efi_disk_write_blocks,
141 	.flush_blocks = &efi_disk_flush_blocks,
142 };
143 
144 static void efi_disk_add_dev(char *name,
145 			     const struct block_drvr *cur_drvr,
146 			     const struct blk_desc *desc,
147 			     int dev_index,
148 			     lbaint_t offset)
149 {
150 	struct efi_disk_obj *diskobj;
151 	struct efi_device_path_file_path *dp;
152 	int objlen = sizeof(*diskobj) + (sizeof(*dp) * 2);
153 
154 	diskobj = calloc(1, objlen);
155 
156 	/* Fill in object data */
157 	diskobj->parent.protocols[0].guid = &efi_block_io_guid;
158 	diskobj->parent.protocols[0].open = efi_disk_open_block;
159 	diskobj->parent.protocols[1].guid = &efi_guid_device_path;
160 	diskobj->parent.protocols[1].open = efi_disk_open_dp;
161 	diskobj->parent.handle = diskobj;
162 	diskobj->ops = block_io_disk_template;
163 	diskobj->ifname = cur_drvr->name;
164 	diskobj->dev_index = dev_index;
165 	diskobj->offset = offset;
166 
167 	/* Fill in EFI IO Media info (for read/write callbacks) */
168 	diskobj->media.removable_media = desc->removable;
169 	diskobj->media.media_present = 1;
170 	diskobj->media.block_size = desc->blksz;
171 	diskobj->media.io_align = desc->blksz;
172 	diskobj->media.last_block = desc->lba;
173 	diskobj->ops.media = &diskobj->media;
174 
175 	/* Fill in device path */
176 	dp = (void*)&diskobj[1];
177 	diskobj->dp = dp;
178 	dp[0].dp.type = DEVICE_PATH_TYPE_MEDIA_DEVICE;
179 	dp[0].dp.sub_type = DEVICE_PATH_SUB_TYPE_FILE_PATH;
180 	dp[0].dp.length = sizeof(*dp);
181 	ascii2unicode(dp[0].str, name);
182 
183 	dp[1].dp.type = DEVICE_PATH_TYPE_END;
184 	dp[1].dp.sub_type = DEVICE_PATH_SUB_TYPE_END;
185 	dp[1].dp.length = sizeof(*dp);
186 
187 	/* Hook up to the device list */
188 	list_add_tail(&diskobj->parent.link, &efi_obj_list);
189 }
190 
191 static int efi_disk_create_eltorito(struct blk_desc *desc,
192 				    const struct block_drvr *cur_drvr,
193 				    int diskid)
194 {
195 	int disks = 0;
196 #ifdef CONFIG_ISO_PARTITION
197 	char devname[32] = { 0 }; /* dp->str is u16[32] long */
198 	disk_partition_t info;
199 	int part = 1;
200 
201 	if (desc->part_type != PART_TYPE_ISO)
202 		return 0;
203 
204 	while (!part_get_info(desc, part, &info)) {
205 		snprintf(devname, sizeof(devname), "%s%d:%d", cur_drvr->name,
206 			 diskid, part);
207 		efi_disk_add_dev(devname, cur_drvr, desc, diskid, info.start);
208 		part++;
209 		disks++;
210 	}
211 #endif
212 
213 	return disks;
214 }
215 
216 /*
217  * U-Boot doesn't have a list of all online disk devices. So when running our
218  * EFI payload, we scan through all of the potentially available ones and
219  * store them in our object pool.
220  *
221  * This gets called from do_bootefi_exec().
222  */
223 int efi_disk_register(void)
224 {
225 	const struct block_drvr *cur_drvr;
226 	int i;
227 	int disks = 0;
228 
229 	/* Search for all available disk devices */
230 	for (cur_drvr = block_drvr; cur_drvr->name; cur_drvr++) {
231 		printf("Scanning disks on %s...\n", cur_drvr->name);
232 		for (i = 0; i < 4; i++) {
233 			struct blk_desc *desc;
234 			char devname[32] = { 0 }; /* dp->str is u16[32] long */
235 
236 			desc = blk_get_dev(cur_drvr->name, i);
237 			if (!desc)
238 				continue;
239 			if (desc->type == DEV_TYPE_UNKNOWN)
240 				continue;
241 
242 			snprintf(devname, sizeof(devname), "%s%d",
243 				 cur_drvr->name, i);
244 			efi_disk_add_dev(devname, cur_drvr, desc, i, 0);
245 			disks++;
246 
247 			/*
248 			 * El Torito images show up as block devices
249 			 * in an EFI world, so let's create them here
250 			 */
251 			disks += efi_disk_create_eltorito(desc, cur_drvr, i);
252 		}
253 	}
254 	printf("Found %d disks\n", disks);
255 
256 	return 0;
257 }
258