efipart.c revision 271135 
1/*-
2 * Copyright (c) 2010 Marcel Moolenaar
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27#include <sys/cdefs.h>
28__FBSDID("$FreeBSD: stable/10/sys/boot/efi/libefi/efipart.c 271135 2014-09-04 21:01:10Z emaste $");
29
30#include <sys/param.h>
31#include <sys/time.h>
32#include <stddef.h>
33#include <stdarg.h>
34
35#include <bootstrap.h>
36
37#include <efi.h>
38#include <efilib.h>
39#include <efiprot.h>
40
41static EFI_GUID blkio_guid = BLOCK_IO_PROTOCOL;
42static EFI_GUID devpath_guid = DEVICE_PATH_PROTOCOL;
43
44static int efipart_init(void);
45static int efipart_strategy(void *, int, daddr_t, size_t, char *, size_t *);
46static int efipart_open(struct open_file *, ...);
47static int efipart_close(struct open_file *);
48static void efipart_print(int);
49
50struct devsw efipart_dev = {
51	.dv_name = "part",
52	.dv_type = DEVT_DISK,
53	.dv_init = efipart_init,
54	.dv_strategy = efipart_strategy,
55	.dv_open = efipart_open,
56	.dv_close = efipart_close,
57	.dv_ioctl = noioctl,
58	.dv_print = efipart_print,
59	.dv_cleanup = NULL
60};
61
62static int
63efipart_init(void)
64{
65	EFI_BLOCK_IO *blkio;
66	EFI_DEVICE_PATH *devpath, *node;
67	EFI_HANDLE *hin, *hout, *aliases, handle;
68	EFI_STATUS status;
69	UINTN sz;
70	CHAR16 *path;
71	u_int n, nin, nout;
72	int err;
73
74	sz = 0;
75	hin = NULL;
76	status = BS->LocateHandle(ByProtocol, &blkio_guid, 0, &sz, 0);
77	if (status == EFI_BUFFER_TOO_SMALL) {
78		hin = (EFI_HANDLE *)malloc(sz * 3);
79		status = BS->LocateHandle(ByProtocol, &blkio_guid, 0, &sz,
80		    hin);
81		if (EFI_ERROR(status))
82			free(hin);
83	}
84	if (EFI_ERROR(status))
85		return (efi_status_to_errno(status));
86
87	/* Filter handles to only include FreeBSD partitions. */
88	nin = sz / sizeof(EFI_HANDLE);
89	hout = hin + nin;
90	aliases = hout + nin;
91	nout = 0;
92
93	bzero(aliases, nin * sizeof(EFI_HANDLE));
94
95	for (n = 0; n < nin; n++) {
96		status = BS->HandleProtocol(hin[n], &devpath_guid,
97		    (void **)&devpath);
98		if (EFI_ERROR(status)) {
99			continue;
100		}
101		node = devpath;
102		while (!IsDevicePathEnd(NextDevicePathNode(node)))
103			node = NextDevicePathNode(node);
104		status = BS->HandleProtocol(hin[n], &blkio_guid,
105		    (void**)&blkio);
106		if (EFI_ERROR(status))
107			continue;
108		if (!blkio->Media->LogicalPartition)
109			continue;
110
111		/*
112		 * If we come across a logical partition of subtype CDROM
113		 * it doesn't refer to the CD filesystem itself, but rather
114		 * to any usable El Torito boot image on it. In this case
115		 * we try to find the parent device and add that instead as
116		 * that will be the CD filesystem.
117		 */
118		if (DevicePathType(node) == MEDIA_DEVICE_PATH &&
119		    DevicePathSubType(node) == MEDIA_CDROM_DP) {
120			node->Type = END_DEVICE_PATH_TYPE;
121			node->SubType = END_ENTIRE_DEVICE_PATH_SUBTYPE;
122			status = BS->LocateDevicePath(&blkio_guid, &devpath,
123			    &handle);
124			if (EFI_ERROR(status))
125				continue;
126			hout[nout] = handle;
127			aliases[nout] = hin[n];
128		} else
129			hout[nout] = hin[n];
130		nout++;
131	}
132
133	err = efi_register_handles(&efipart_dev, hout, aliases, nout);
134	free(hin);
135	return (err);
136}
137
138static void
139efipart_print(int verbose)
140{
141	char line[80];
142	EFI_BLOCK_IO *blkio;
143	EFI_HANDLE h;
144	EFI_STATUS status;
145	u_int unit;
146
147	for (unit = 0, h = efi_find_handle(&efipart_dev, 0);
148	    h != NULL; h = efi_find_handle(&efipart_dev, ++unit)) {
149		sprintf(line, "    %s%d:", efipart_dev.dv_name, unit);
150		pager_output(line);
151
152		status = BS->HandleProtocol(h, &blkio_guid, (void **)&blkio);
153		if (!EFI_ERROR(status)) {
154			sprintf(line, "    %llu blocks",
155			    (unsigned long long)(blkio->Media->LastBlock + 1));
156			pager_output(line);
157			if (blkio->Media->RemovableMedia)
158				pager_output(" (removable)");
159		}
160		pager_output("\n");
161	}
162}
163
164static int
165efipart_open(struct open_file *f, ...)
166{
167	va_list args;
168	struct devdesc *dev;
169	EFI_BLOCK_IO *blkio;
170	EFI_HANDLE h;
171	EFI_STATUS status;
172
173	va_start(args, f);
174	dev = va_arg(args, struct devdesc*);
175	va_end(args);
176
177	h = efi_find_handle(&efipart_dev, dev->d_unit);
178	if (h == NULL)
179		return (EINVAL);
180
181	status = BS->HandleProtocol(h, &blkio_guid, (void **)&blkio);
182	if (EFI_ERROR(status))
183		return (efi_status_to_errno(status));
184
185	if (!blkio->Media->MediaPresent)
186		return (EAGAIN);
187
188	dev->d_opendata = blkio;
189	return (0);
190}
191
192static int
193efipart_close(struct open_file *f)
194{
195	struct devdesc *dev;
196
197	dev = (struct devdesc *)(f->f_devdata);
198	if (dev->d_opendata == NULL)
199		return (EINVAL);
200
201	dev->d_opendata = NULL;
202	return (0);
203}
204
205/*
206 * efipart_readwrite()
207 * Internal equivalent of efipart_strategy(), which operates on the
208 * media-native block size. This function expects all I/O requests
209 * to be within the media size and returns an error if such is not
210 * the case.
211 */
212static int
213efipart_readwrite(EFI_BLOCK_IO *blkio, int rw, daddr_t blk, daddr_t nblks,
214    char *buf)
215{
216	EFI_STATUS status;
217
218	if (blkio == NULL)
219		return (ENXIO);
220	if (blk < 0 || blk > blkio->Media->LastBlock)
221		return (EIO);
222	if ((blk + nblks - 1) > blkio->Media->LastBlock)
223		return (EIO);
224
225	switch (rw) {
226	case F_READ:
227		status = blkio->ReadBlocks(blkio, blkio->Media->MediaId, blk,
228		    nblks * blkio->Media->BlockSize, buf);
229		break;
230	case F_WRITE:
231		if (blkio->Media->ReadOnly)
232			return (EROFS);
233		status = blkio->WriteBlocks(blkio, blkio->Media->MediaId, blk,
234		    nblks * blkio->Media->BlockSize, buf);
235		break;
236	default:
237		return (ENOSYS);
238	}
239
240	if (EFI_ERROR(status))
241		printf("%s: rw=%d, status=%lu\n", __func__, rw, (u_long)status);
242	return (efi_status_to_errno(status));
243}
244
245static int
246efipart_strategy(void *devdata, int rw, daddr_t blk, size_t size, char *buf,
247    size_t *rsize)
248{
249	struct devdesc *dev = (struct devdesc *)devdata;
250	EFI_BLOCK_IO *blkio;
251	off_t off;
252	char *blkbuf;
253	size_t blkoff, blksz;
254	int error;
255
256	if (dev == NULL || blk < 0)
257		return (EINVAL);
258
259	blkio = dev->d_opendata;
260	if (blkio == NULL)
261		return (ENXIO);
262
263	if (size == 0 || (size % 512) != 0)
264		return (EIO);
265
266	if (rsize != NULL)
267		*rsize = size;
268
269	if (blkio->Media->BlockSize == 512)
270		return (efipart_readwrite(blkio, rw, blk, size / 512, buf));
271
272	/*
273	 * The block size of the media is not 512B per sector.
274	 */
275	blkbuf = malloc(blkio->Media->BlockSize);
276	if (blkbuf == NULL)
277		return (ENOMEM);
278
279	error = 0;
280	off = blk * 512;
281	blk = off / blkio->Media->BlockSize;
282	blkoff = off % blkio->Media->BlockSize;
283	blksz = blkio->Media->BlockSize - blkoff;
284	while (size > 0) {
285		error = efipart_readwrite(blkio, rw, blk, 1, blkbuf);
286		if (error)
287			break;
288		if (size < blksz)
289			blksz = size;
290		bcopy(blkbuf + blkoff, buf, blksz);
291		buf += blksz;
292		size -= blksz;
293		blk++;
294		blkoff = 0;
295		blksz = blkio->Media->BlockSize;
296	}
297
298	free(blkbuf);
299	return (error);
300}
301