efipart.c revision 294981 
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 294981 2016-01-28 12:11:42Z smh $");
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, *devpathcpy, *tmpdevpath, *node;
67	EFI_HANDLE *hin, *hout, *aliases, handle;
68	EFI_STATUS status;
69	UINTN sz;
70	u_int n, nin, nout;
71	int err;
72	size_t devpathlen;
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
102		node = devpath;
103		devpathlen = DevicePathNodeLength(node);
104		while (!IsDevicePathEnd(NextDevicePathNode(node))) {
105			node = NextDevicePathNode(node);
106			devpathlen += DevicePathNodeLength(node);
107		}
108		devpathlen += DevicePathNodeLength(NextDevicePathNode(node));
109
110		status = BS->HandleProtocol(hin[n], &blkio_guid,
111		    (void**)&blkio);
112		if (EFI_ERROR(status))
113			continue;
114		if (!blkio->Media->LogicalPartition)
115			continue;
116
117		/*
118		 * If we come across a logical partition of subtype CDROM
119		 * it doesn't refer to the CD filesystem itself, but rather
120		 * to any usable El Torito boot image on it. In this case
121		 * we try to find the parent device and add that instead as
122		 * that will be the CD filesystem.
123		 */
124		if (DevicePathType(node) == MEDIA_DEVICE_PATH &&
125		    DevicePathSubType(node) == MEDIA_CDROM_DP) {
126			devpathcpy = malloc(devpathlen);
127			memcpy(devpathcpy, devpath, devpathlen);
128			node = devpathcpy;
129			while (!IsDevicePathEnd(NextDevicePathNode(node)))
130				node = NextDevicePathNode(node);
131			SetDevicePathEndNode(node);
132			tmpdevpath = devpathcpy;
133			status = BS->LocateDevicePath(&blkio_guid, &tmpdevpath,
134			    &handle);
135			free(devpathcpy);
136			if (EFI_ERROR(status))
137				continue;
138			hout[nout] = handle;
139			aliases[nout] = hin[n];
140		} else
141			hout[nout] = hin[n];
142		nout++;
143	}
144
145	err = efi_register_handles(&efipart_dev, hout, aliases, nout);
146	free(hin);
147	return (err);
148}
149
150static void
151efipart_print(int verbose)
152{
153	char line[80];
154	EFI_BLOCK_IO *blkio;
155	EFI_HANDLE h;
156	EFI_STATUS status;
157	u_int unit;
158
159	for (unit = 0, h = efi_find_handle(&efipart_dev, 0);
160	    h != NULL; h = efi_find_handle(&efipart_dev, ++unit)) {
161		sprintf(line, "    %s%d:", efipart_dev.dv_name, unit);
162		pager_output(line);
163
164		status = BS->HandleProtocol(h, &blkio_guid, (void **)&blkio);
165		if (!EFI_ERROR(status)) {
166			sprintf(line, "    %llu blocks",
167			    (unsigned long long)(blkio->Media->LastBlock + 1));
168			pager_output(line);
169			if (blkio->Media->RemovableMedia)
170				pager_output(" (removable)");
171		}
172		pager_output("\n");
173	}
174}
175
176static int
177efipart_open(struct open_file *f, ...)
178{
179	va_list args;
180	struct devdesc *dev;
181	EFI_BLOCK_IO *blkio;
182	EFI_HANDLE h;
183	EFI_STATUS status;
184
185	va_start(args, f);
186	dev = va_arg(args, struct devdesc*);
187	va_end(args);
188
189	h = efi_find_handle(&efipart_dev, dev->d_unit);
190	if (h == NULL)
191		return (EINVAL);
192
193	status = BS->HandleProtocol(h, &blkio_guid, (void **)&blkio);
194	if (EFI_ERROR(status))
195		return (efi_status_to_errno(status));
196
197	if (!blkio->Media->MediaPresent)
198		return (EAGAIN);
199
200	dev->d_opendata = blkio;
201	return (0);
202}
203
204static int
205efipart_close(struct open_file *f)
206{
207	struct devdesc *dev;
208
209	dev = (struct devdesc *)(f->f_devdata);
210	if (dev->d_opendata == NULL)
211		return (EINVAL);
212
213	dev->d_opendata = NULL;
214	return (0);
215}
216
217/*
218 * efipart_readwrite()
219 * Internal equivalent of efipart_strategy(), which operates on the
220 * media-native block size. This function expects all I/O requests
221 * to be within the media size and returns an error if such is not
222 * the case.
223 */
224static int
225efipart_readwrite(EFI_BLOCK_IO *blkio, int rw, daddr_t blk, daddr_t nblks,
226    char *buf)
227{
228	EFI_STATUS status;
229
230	if (blkio == NULL)
231		return (ENXIO);
232	if (blk < 0 || blk > blkio->Media->LastBlock)
233		return (EIO);
234	if ((blk + nblks - 1) > blkio->Media->LastBlock)
235		return (EIO);
236
237	switch (rw) {
238	case F_READ:
239		status = blkio->ReadBlocks(blkio, blkio->Media->MediaId, blk,
240		    nblks * blkio->Media->BlockSize, buf);
241		break;
242	case F_WRITE:
243		if (blkio->Media->ReadOnly)
244			return (EROFS);
245		status = blkio->WriteBlocks(blkio, blkio->Media->MediaId, blk,
246		    nblks * blkio->Media->BlockSize, buf);
247		break;
248	default:
249		return (ENOSYS);
250	}
251
252	if (EFI_ERROR(status))
253		printf("%s: rw=%d, status=%lu\n", __func__, rw, (u_long)status);
254	return (efi_status_to_errno(status));
255}
256
257static int
258efipart_strategy(void *devdata, int rw, daddr_t blk, size_t size, char *buf,
259    size_t *rsize)
260{
261	struct devdesc *dev = (struct devdesc *)devdata;
262	EFI_BLOCK_IO *blkio;
263	off_t off;
264	char *blkbuf;
265	size_t blkoff, blksz;
266	int error;
267
268	if (dev == NULL || blk < 0)
269		return (EINVAL);
270
271	blkio = dev->d_opendata;
272	if (blkio == NULL)
273		return (ENXIO);
274
275	if (size == 0 || (size % 512) != 0)
276		return (EIO);
277
278	if (rsize != NULL)
279		*rsize = size;
280
281	if (blkio->Media->BlockSize == 512)
282		return (efipart_readwrite(blkio, rw, blk, size / 512, buf));
283
284	/*
285	 * The block size of the media is not 512B per sector.
286	 */
287	blkbuf = malloc(blkio->Media->BlockSize);
288	if (blkbuf == NULL)
289		return (ENOMEM);
290
291	error = 0;
292	off = blk * 512;
293	blk = off / blkio->Media->BlockSize;
294	blkoff = off % blkio->Media->BlockSize;
295	blksz = blkio->Media->BlockSize - blkoff;
296	while (size > 0) {
297		error = efipart_readwrite(blkio, rw, blk, 1, blkbuf);
298		if (error)
299			break;
300		if (size < blksz)
301			blksz = size;
302		bcopy(blkbuf + blkoff, buf, blksz);
303		buf += blksz;
304		size -= blksz;
305		blk++;
306		blkoff = 0;
307		blksz = blkio->Media->BlockSize;
308	}
309
310	free(blkbuf);
311	return (error);
312}
313