xref: /openbmc/u-boot/lib/efi_loader/efi_disk.c (revision 7b384eccc785b596f68448b155cbda26df57fb23)
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 <inttypes.h>
13  #include <part.h>
14  #include <malloc.h>
15  
16  const efi_guid_t efi_block_io_guid = BLOCK_IO_GUID;
17  
18  struct efi_disk_obj {
19  	/* Generic EFI object parent class data */
20  	struct efi_object parent;
21  	/* EFI Interface callback struct for block I/O */
22  	struct efi_block_io ops;
23  	/* U-Boot ifname for block device */
24  	const char *ifname;
25  	/* U-Boot dev_index for block device */
26  	int dev_index;
27  	/* EFI Interface Media descriptor struct, referenced by ops */
28  	struct efi_block_io_media media;
29  	/* EFI device path to this block device */
30  	struct efi_device_path *dp;
31  	/* partition # */
32  	unsigned int part;
33  	/* handle to filesys proto (for partition objects) */
34  	struct efi_simple_file_system_protocol *volume;
35  	/* Offset into disk for simple partitions */
36  	lbaint_t offset;
37  	/* Internal block device */
38  	struct blk_desc *desc;
39  };
40  
41  static efi_status_t EFIAPI efi_disk_reset(struct efi_block_io *this,
42  			char extended_verification)
43  {
44  	EFI_ENTRY("%p, %x", this, extended_verification);
45  	return EFI_EXIT(EFI_DEVICE_ERROR);
46  }
47  
48  enum efi_disk_direction {
49  	EFI_DISK_READ,
50  	EFI_DISK_WRITE,
51  };
52  
53  static efi_status_t efi_disk_rw_blocks(struct efi_block_io *this,
54  			u32 media_id, u64 lba, unsigned long buffer_size,
55  			void *buffer, enum efi_disk_direction direction)
56  {
57  	struct efi_disk_obj *diskobj;
58  	struct blk_desc *desc;
59  	int blksz;
60  	int blocks;
61  	unsigned long n;
62  
63  	diskobj = container_of(this, struct efi_disk_obj, ops);
64  	desc = (struct blk_desc *) diskobj->desc;
65  	blksz = desc->blksz;
66  	blocks = buffer_size / blksz;
67  	lba += diskobj->offset;
68  
69  	debug("EFI: %s:%d blocks=%x lba=%"PRIx64" blksz=%x dir=%d\n", __func__,
70  	      __LINE__, blocks, lba, blksz, direction);
71  
72  	/* We only support full block access */
73  	if (buffer_size & (blksz - 1))
74  		return EFI_DEVICE_ERROR;
75  
76  	if (direction == EFI_DISK_READ)
77  		n = blk_dread(desc, lba, blocks, buffer);
78  	else
79  		n = blk_dwrite(desc, lba, blocks, buffer);
80  
81  	/* We don't do interrupts, so check for timers cooperatively */
82  	efi_timer_check();
83  
84  	debug("EFI: %s:%d n=%lx blocks=%x\n", __func__, __LINE__, n, blocks);
85  
86  	if (n != blocks)
87  		return EFI_DEVICE_ERROR;
88  
89  	return EFI_SUCCESS;
90  }
91  
92  static efi_status_t EFIAPI efi_disk_read_blocks(struct efi_block_io *this,
93  			u32 media_id, u64 lba, efi_uintn_t buffer_size,
94  			void *buffer)
95  {
96  	void *real_buffer = buffer;
97  	efi_status_t r;
98  
99  #ifdef CONFIG_EFI_LOADER_BOUNCE_BUFFER
100  	if (buffer_size > EFI_LOADER_BOUNCE_BUFFER_SIZE) {
101  		r = efi_disk_read_blocks(this, media_id, lba,
102  			EFI_LOADER_BOUNCE_BUFFER_SIZE, buffer);
103  		if (r != EFI_SUCCESS)
104  			return r;
105  		return efi_disk_read_blocks(this, media_id, lba +
106  			EFI_LOADER_BOUNCE_BUFFER_SIZE / this->media->block_size,
107  			buffer_size - EFI_LOADER_BOUNCE_BUFFER_SIZE,
108  			buffer + EFI_LOADER_BOUNCE_BUFFER_SIZE);
109  	}
110  
111  	real_buffer = efi_bounce_buffer;
112  #endif
113  
114  	EFI_ENTRY("%p, %x, %" PRIx64 ", %zx, %p", this, media_id, lba,
115  		  buffer_size, buffer);
116  
117  	r = efi_disk_rw_blocks(this, media_id, lba, buffer_size, real_buffer,
118  			       EFI_DISK_READ);
119  
120  	/* Copy from bounce buffer to real buffer if necessary */
121  	if ((r == EFI_SUCCESS) && (real_buffer != buffer))
122  		memcpy(buffer, real_buffer, buffer_size);
123  
124  	return EFI_EXIT(r);
125  }
126  
127  static efi_status_t EFIAPI efi_disk_write_blocks(struct efi_block_io *this,
128  			u32 media_id, u64 lba, efi_uintn_t buffer_size,
129  			void *buffer)
130  {
131  	void *real_buffer = buffer;
132  	efi_status_t r;
133  
134  #ifdef CONFIG_EFI_LOADER_BOUNCE_BUFFER
135  	if (buffer_size > EFI_LOADER_BOUNCE_BUFFER_SIZE) {
136  		r = efi_disk_write_blocks(this, media_id, lba,
137  			EFI_LOADER_BOUNCE_BUFFER_SIZE, buffer);
138  		if (r != EFI_SUCCESS)
139  			return r;
140  		return efi_disk_write_blocks(this, media_id, lba +
141  			EFI_LOADER_BOUNCE_BUFFER_SIZE / this->media->block_size,
142  			buffer_size - EFI_LOADER_BOUNCE_BUFFER_SIZE,
143  			buffer + EFI_LOADER_BOUNCE_BUFFER_SIZE);
144  	}
145  
146  	real_buffer = efi_bounce_buffer;
147  #endif
148  
149  	EFI_ENTRY("%p, %x, %" PRIx64 ", %zx, %p", this, media_id, lba,
150  		  buffer_size, buffer);
151  
152  	/* Populate bounce buffer if necessary */
153  	if (real_buffer != buffer)
154  		memcpy(real_buffer, buffer, buffer_size);
155  
156  	r = efi_disk_rw_blocks(this, media_id, lba, buffer_size, real_buffer,
157  			       EFI_DISK_WRITE);
158  
159  	return EFI_EXIT(r);
160  }
161  
162  static efi_status_t EFIAPI efi_disk_flush_blocks(struct efi_block_io *this)
163  {
164  	/* We always write synchronously */
165  	EFI_ENTRY("%p", this);
166  	return EFI_EXIT(EFI_SUCCESS);
167  }
168  
169  static const struct efi_block_io block_io_disk_template = {
170  	.reset = &efi_disk_reset,
171  	.read_blocks = &efi_disk_read_blocks,
172  	.write_blocks = &efi_disk_write_blocks,
173  	.flush_blocks = &efi_disk_flush_blocks,
174  };
175  
176  /*
177   * Get the simple file system protocol for a file device path.
178   *
179   * The full path provided is split into device part and into a file
180   * part. The device part is used to find the handle on which the
181   * simple file system protocol is installed.
182   *
183   * @full_path	device path including device and file
184   * @return	simple file system protocol
185   */
186  struct efi_simple_file_system_protocol *
187  efi_fs_from_path(struct efi_device_path *full_path)
188  {
189  	struct efi_object *efiobj;
190  	struct efi_handler *handler;
191  	struct efi_device_path *device_path;
192  	struct efi_device_path *file_path;
193  	efi_status_t ret;
194  
195  	/* Split the path into a device part and a file part */
196  	ret = efi_dp_split_file_path(full_path, &device_path, &file_path);
197  	if (ret != EFI_SUCCESS)
198  		return NULL;
199  	efi_free_pool(file_path);
200  
201  	/* Get the EFI object for the partition */
202  	efiobj = efi_dp_find_obj(device_path, NULL);
203  	efi_free_pool(device_path);
204  	if (!efiobj)
205  		return NULL;
206  
207  	/* Find the simple file system protocol */
208  	ret = efi_search_protocol(efiobj, &efi_simple_file_system_protocol_guid,
209  				  &handler);
210  	if (ret != EFI_SUCCESS)
211  		return NULL;
212  
213  	/* Return the simple file system protocol for the partition */
214  	return handler->protocol_interface;
215  }
216  
217  /*
218   * Create a handle for a partition or disk
219   *
220   * @parent	parent handle
221   * @dp_parent	parent device path
222   * @if_typename interface name for block device
223   * @desc	internal block device
224   * @dev_index   device index for block device
225   * @offset	offset into disk for simple partitions
226   * @return	disk object
227   */
228  static efi_status_t efi_disk_add_dev(
229  				efi_handle_t parent,
230  				struct efi_device_path *dp_parent,
231  				const char *if_typename,
232  				struct blk_desc *desc,
233  				int dev_index,
234  				lbaint_t offset,
235  				unsigned int part,
236  				struct efi_disk_obj **disk)
237  {
238  	struct efi_disk_obj *diskobj;
239  	efi_status_t ret;
240  
241  	/* Don't add empty devices */
242  	if (!desc->lba)
243  		return EFI_NOT_READY;
244  
245  	diskobj = calloc(1, sizeof(*diskobj));
246  	if (!diskobj)
247  		return EFI_OUT_OF_RESOURCES;
248  
249  	/* Hook up to the device list */
250  	efi_add_handle(&diskobj->parent);
251  
252  	/* Fill in object data */
253  	if (part) {
254  		struct efi_device_path *node = efi_dp_part_node(desc, part);
255  
256  		diskobj->dp = efi_dp_append_node(dp_parent, node);
257  		efi_free_pool(node);
258  	} else {
259  		diskobj->dp = efi_dp_from_part(desc, part);
260  	}
261  	diskobj->part = part;
262  	ret = efi_add_protocol(diskobj->parent.handle, &efi_block_io_guid,
263  			       &diskobj->ops);
264  	if (ret != EFI_SUCCESS)
265  		return ret;
266  	ret = efi_add_protocol(diskobj->parent.handle, &efi_guid_device_path,
267  			       diskobj->dp);
268  	if (ret != EFI_SUCCESS)
269  		return ret;
270  	if (part >= 1) {
271  		diskobj->volume = efi_simple_file_system(desc, part,
272  							 diskobj->dp);
273  		ret = efi_add_protocol(diskobj->parent.handle,
274  				       &efi_simple_file_system_protocol_guid,
275  				       diskobj->volume);
276  		if (ret != EFI_SUCCESS)
277  			return ret;
278  	}
279  	diskobj->ops = block_io_disk_template;
280  	diskobj->ifname = if_typename;
281  	diskobj->dev_index = dev_index;
282  	diskobj->offset = offset;
283  	diskobj->desc = desc;
284  
285  	/* Fill in EFI IO Media info (for read/write callbacks) */
286  	diskobj->media.removable_media = desc->removable;
287  	diskobj->media.media_present = 1;
288  	diskobj->media.block_size = desc->blksz;
289  	diskobj->media.io_align = desc->blksz;
290  	diskobj->media.last_block = desc->lba - offset;
291  	if (part != 0)
292  		diskobj->media.logical_partition = 1;
293  	diskobj->ops.media = &diskobj->media;
294  	if (disk)
295  		*disk = diskobj;
296  	return EFI_SUCCESS;
297  }
298  
299  /*
300   * Create handles and protocols for the partitions of a block device
301   *
302   * @parent		handle of the parent disk
303   * @blk_desc		block device
304   * @if_typename		interface type
305   * @diskid		device number
306   * @pdevname		device name
307   * @return		number of partitions created
308   */
309  int efi_disk_create_partitions(efi_handle_t parent, struct blk_desc *desc,
310  			       const char *if_typename, int diskid,
311  			       const char *pdevname)
312  {
313  	int disks = 0;
314  	char devname[32] = { 0 }; /* dp->str is u16[32] long */
315  	disk_partition_t info;
316  	int part;
317  	struct efi_device_path *dp = NULL;
318  	efi_status_t ret;
319  	struct efi_handler *handler;
320  
321  	/* Get the device path of the parent */
322  	ret = efi_search_protocol(parent, &efi_guid_device_path, &handler);
323  	if (ret == EFI_SUCCESS)
324  		dp = handler->protocol_interface;
325  
326  	/* Add devices for each partition */
327  	for (part = 1; part <= MAX_SEARCH_PARTITIONS; part++) {
328  		if (part_get_info(desc, part, &info))
329  			continue;
330  		snprintf(devname, sizeof(devname), "%s:%d", pdevname,
331  			 part);
332  		ret = efi_disk_add_dev(parent, dp, if_typename, desc, diskid,
333  				       info.start, part, NULL);
334  		if (ret != EFI_SUCCESS) {
335  			printf("Adding partition %s failed\n", pdevname);
336  			continue;
337  		}
338  		disks++;
339  	}
340  
341  	return disks;
342  }
343  
344  /*
345   * U-Boot doesn't have a list of all online disk devices. So when running our
346   * EFI payload, we scan through all of the potentially available ones and
347   * store them in our object pool.
348   *
349   * TODO(sjg@chromium.org): Actually with CONFIG_BLK, U-Boot does have this.
350   * Consider converting the code to look up devices as needed. The EFI device
351   * could be a child of the UCLASS_BLK block device, perhaps.
352   *
353   * This gets called from do_bootefi_exec().
354   */
355  efi_status_t efi_disk_register(void)
356  {
357  	struct efi_disk_obj *disk;
358  	int disks = 0;
359  	efi_status_t ret;
360  #ifdef CONFIG_BLK
361  	struct udevice *dev;
362  
363  	for (uclass_first_device_check(UCLASS_BLK, &dev); dev;
364  	     uclass_next_device_check(&dev)) {
365  		struct blk_desc *desc = dev_get_uclass_platdata(dev);
366  		const char *if_typename = blk_get_if_type_name(desc->if_type);
367  
368  		/* Add block device for the full device */
369  		printf("Scanning disk %s...\n", dev->name);
370  		ret = efi_disk_add_dev(NULL, NULL, if_typename,
371  					desc, desc->devnum, 0, 0, &disk);
372  		if (ret == EFI_NOT_READY) {
373  			printf("Disk %s not ready\n", dev->name);
374  			continue;
375  		}
376  		if (ret) {
377  			printf("ERROR: failure to add disk device %s, r = %lu\n",
378  			       dev->name, ret & ~EFI_ERROR_MASK);
379  			return ret;
380  		}
381  		disks++;
382  
383  		/* Partitions show up as block devices in EFI */
384  		disks += efi_disk_create_partitions(
385  					disk->parent.handle, desc, if_typename,
386  					desc->devnum, dev->name);
387  	}
388  #else
389  	int i, if_type;
390  
391  	/* Search for all available disk devices */
392  	for (if_type = 0; if_type < IF_TYPE_COUNT; if_type++) {
393  		const struct blk_driver *cur_drvr;
394  		const char *if_typename;
395  
396  		cur_drvr = blk_driver_lookup_type(if_type);
397  		if (!cur_drvr)
398  			continue;
399  
400  		if_typename = cur_drvr->if_typename;
401  		printf("Scanning disks on %s...\n", if_typename);
402  		for (i = 0; i < 4; i++) {
403  			struct blk_desc *desc;
404  			char devname[32] = { 0 }; /* dp->str is u16[32] long */
405  
406  			desc = blk_get_devnum_by_type(if_type, i);
407  			if (!desc)
408  				continue;
409  			if (desc->type == DEV_TYPE_UNKNOWN)
410  				continue;
411  
412  			snprintf(devname, sizeof(devname), "%s%d",
413  				 if_typename, i);
414  
415  			/* Add block device for the full device */
416  			ret = efi_disk_add_dev(NULL, NULL, if_typename, desc,
417  					       i, 0, 0, &disk);
418  			if (ret == EFI_NOT_READY) {
419  				printf("Disk %s not ready\n", devname);
420  				continue;
421  			}
422  			if (ret) {
423  				printf("ERROR: failure to add disk device %s, r = %lu\n",
424  				       devname, ret & ~EFI_ERROR_MASK);
425  				return ret;
426  			}
427  			disks++;
428  
429  			/* Partitions show up as block devices in EFI */
430  			disks += efi_disk_create_partitions(
431  						disk->parent.handle, desc,
432  						if_typename, i, devname);
433  		}
434  	}
435  #endif
436  	printf("Found %d disks\n", disks);
437  
438  	return EFI_SUCCESS;
439  }
440