efipart.c revision 285951 
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 285951 2015-07-28 12:45:08Z 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, *devpathcpy, *tmpdevpath, *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	size_t devpathlen;
74
75	sz = 0;
76	hin = NULL;
77	status = BS->LocateHandle(ByProtocol, &blkio_guid, 0, &sz, 0);
78	if (status == EFI_BUFFER_TOO_SMALL) {
79		hin = (EFI_HANDLE *)malloc(sz * 3);
80		status = BS->LocateHandle(ByProtocol, &blkio_guid, 0, &sz,
81		    hin);
82		if (EFI_ERROR(status))
83			free(hin);
84	}
85	if (EFI_ERROR(status))
86		return (efi_status_to_errno(status));
87
88	/* Filter handles to only include FreeBSD partitions. */
89	nin = sz / sizeof(EFI_HANDLE);
90	hout = hin + nin;
91	aliases = hout + nin;
92	nout = 0;
93
94	bzero(aliases, nin * sizeof(EFI_HANDLE));
95
96	for (n = 0; n < nin; n++) {
97		status = BS->HandleProtocol(hin[n], &devpath_guid,
98		    (void **)&devpath);
99		if (EFI_ERROR(status)) {
100			continue;
101		}
102
103		node = devpath;
104		devpathlen = DevicePathNodeLength(node);
105		while (!IsDevicePathEnd(NextDevicePathNode(node))) {
106			node = NextDevicePathNode(node);
107			devpathlen += DevicePathNodeLength(node);
108		}
109		devpathlen += DevicePathNodeLength(NextDevicePathNode(node));
110
111		status = BS->HandleProtocol(hin[n], &blkio_guid,
112		    (void**)&blkio);
113		if (EFI_ERROR(status))
114			continue;
115		if (!blkio->Media->LogicalPartition)
116			continue;
117
118		/*
119		 * If we come across a logical partition of subtype CDROM
120		 * it doesn't refer to the CD filesystem itself, but rather
121		 * to any usable El Torito boot image on it. In this case
122		 * we try to find the parent device and add that instead as
123		 * that will be the CD filesystem.
124		 */
125		if (DevicePathType(node) == MEDIA_DEVICE_PATH &&
126		    DevicePathSubType(node) == MEDIA_CDROM_DP) {
127			devpathcpy = malloc(devpathlen);
128			memcpy(devpathcpy, devpath, devpathlen);
129			node = devpathcpy;
130			while (!IsDevicePathEnd(NextDevicePathNode(node)))
131				node = NextDevicePathNode(node);
132			SetDevicePathEndNode(node);
133			tmpdevpath = devpathcpy;
134			status = BS->LocateDevicePath(&blkio_guid, &tmpdevpath,
135			    &handle);
136			free(devpathcpy);
137			if (EFI_ERROR(status))
138				continue;
139			hout[nout] = handle;
140			aliases[nout] = hin[n];
141		} else
142			hout[nout] = hin[n];
143		nout++;
144	}
145
146	err = efi_register_handles(&efipart_dev, hout, aliases, nout);
147	free(hin);
148	return (err);
149}
150
151static void
152efipart_print(int verbose)
153{
154	char line[80];
155	EFI_BLOCK_IO *blkio;
156	EFI_HANDLE h;
157	EFI_STATUS status;
158	u_int unit;
159
160	for (unit = 0, h = efi_find_handle(&efipart_dev, 0);
161	    h != NULL; h = efi_find_handle(&efipart_dev, ++unit)) {
162		sprintf(line, "    %s%d:", efipart_dev.dv_name, unit);
163		pager_output(line);
164
165		status = BS->HandleProtocol(h, &blkio_guid, (void **)&blkio);
166		if (!EFI_ERROR(status)) {
167			sprintf(line, "    %llu blocks",
168			    (unsigned long long)(blkio->Media->LastBlock + 1));
169			pager_output(line);
170			if (blkio->Media->RemovableMedia)
171				pager_output(" (removable)");
172		}
173		pager_output("\n");
174	}
175}
176
177static int
178efipart_open(struct open_file *f, ...)
179{
180	va_list args;
181	struct devdesc *dev;
182	EFI_BLOCK_IO *blkio;
183	EFI_HANDLE h;
184	EFI_STATUS status;
185
186	va_start(args, f);
187	dev = va_arg(args, struct devdesc*);
188	va_end(args);
189
190	h = efi_find_handle(&efipart_dev, dev->d_unit);
191	if (h == NULL)
192		return (EINVAL);
193
194	status = BS->HandleProtocol(h, &blkio_guid, (void **)&blkio);
195	if (EFI_ERROR(status))
196		return (efi_status_to_errno(status));
197
198	if (!blkio->Media->MediaPresent)
199		return (EAGAIN);
200
201	dev->d_opendata = blkio;
202	return (0);
203}
204
205static int
206efipart_close(struct open_file *f)
207{
208	struct devdesc *dev;
209
210	dev = (struct devdesc *)(f->f_devdata);
211	if (dev->d_opendata == NULL)
212		return (EINVAL);
213
214	dev->d_opendata = NULL;
215	return (0);
216}
217
218/*
219 * efipart_readwrite()
220 * Internal equivalent of efipart_strategy(), which operates on the
221 * media-native block size. This function expects all I/O requests
222 * to be within the media size and returns an error if such is not
223 * the case.
224 */
225static int
226efipart_readwrite(EFI_BLOCK_IO *blkio, int rw, daddr_t blk, daddr_t nblks,
227    char *buf)
228{
229	EFI_STATUS status;
230
231	if (blkio == NULL)
232		return (ENXIO);
233	if (blk < 0 || blk > blkio->Media->LastBlock)
234		return (EIO);
235	if ((blk + nblks - 1) > blkio->Media->LastBlock)
236		return (EIO);
237
238	switch (rw) {
239	case F_READ:
240		status = blkio->ReadBlocks(blkio, blkio->Media->MediaId, blk,
241		    nblks * blkio->Media->BlockSize, buf);
242		break;
243	case F_WRITE:
244		if (blkio->Media->ReadOnly)
245			return (EROFS);
246		status = blkio->WriteBlocks(blkio, blkio->Media->MediaId, blk,
247		    nblks * blkio->Media->BlockSize, buf);
248		break;
249	default:
250		return (ENOSYS);
251	}
252
253	if (EFI_ERROR(status))
254		printf("%s: rw=%d, status=%lu\n", __func__, rw, (u_long)status);
255	return (efi_status_to_errno(status));
256}
257
258static int
259efipart_strategy(void *devdata, int rw, daddr_t blk, size_t size, char *buf,
260    size_t *rsize)
261{
262	struct devdesc *dev = (struct devdesc *)devdata;
263	EFI_BLOCK_IO *blkio;
264	off_t off;
265	char *blkbuf;
266	size_t blkoff, blksz;
267	int error;
268
269	if (dev == NULL || blk < 0)
270		return (EINVAL);
271
272	blkio = dev->d_opendata;
273	if (blkio == NULL)
274		return (ENXIO);
275
276	if (size == 0 || (size % 512) != 0)
277		return (EIO);
278
279	if (rsize != NULL)
280		*rsize = size;
281
282	if (blkio->Media->BlockSize == 512)
283		return (efipart_readwrite(blkio, rw, blk, size / 512, buf));
284
285	/*
286	 * The block size of the media is not 512B per sector.
287	 */
288	blkbuf = malloc(blkio->Media->BlockSize);
289	if (blkbuf == NULL)
290		return (ENOMEM);
291
292	error = 0;
293	off = blk * 512;
294	blk = off / blkio->Media->BlockSize;
295	blkoff = off % blkio->Media->BlockSize;
296	blksz = blkio->Media->BlockSize - blkoff;
297	while (size > 0) {
298		error = efipart_readwrite(blkio, rw, blk, 1, blkbuf);
299		if (error)
300			break;
301		if (size < blksz)
302			blksz = size;
303		bcopy(blkbuf + blkoff, buf, blksz);
304		buf += blksz;
305		size -= blksz;
306		blk++;
307		blkoff = 0;
308		blksz = blkio->Media->BlockSize;
309	}
310
311	free(blkbuf);
312	return (error);
313}
314