1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 
27 #ifndef _LIBFDISK_H_
28 #define	_LIBFDISK_H_
29 
30 #include <limits.h>
31 #include <sys/dktp/fdisk.h>
32 
33 #ifdef	__cplusplus
34 extern "C" {
35 #endif
36 
37 #define	MAX_LOGDRIVE_OFFSET 63
38 
39 #define	FDISK_ERRNO		200
40 #define	FDISK_ETOOLONG		(FDISK_ERRNO + 0)
41 #define	FDISK_EOOBOUND		(FDISK_ERRNO + 1)
42 #define	FDISK_EZERO		(FDISK_ERRNO + 2)
43 #define	FDISK_EOVERLAP		(FDISK_ERRNO + 3)
44 #define	FDISK_ENOVGEOM		(FDISK_ERRNO + 4)
45 #define	FDISK_ENOPGEOM		(FDISK_ERRNO + 5)
46 #define	FDISK_ENOLGEOM		(FDISK_ERRNO + 6)
47 #define	FDISK_ENOLOGDRIVE	(FDISK_ERRNO + 7)
48 #define	FDISK_EBADLOGDRIVE	(FDISK_ERRNO + 8)
49 #define	FDISK_ENOEXTPART	(FDISK_ERRNO + 9)
50 #define	FDISK_EBADMAGIC		(FDISK_ERRNO + 10)
51 #define	FDISK_EMOUNTED		(FDISK_ERRNO + 11)
52 
53 #define	FDISK_SUCCESS 0
54 
55 #define	FDISK_READ_DISK		0x00000001
56 
57 #define	LINUX_SWAP_MAGIC_LENGTH	10
58 enum {
59 	PHYSGEOM = 0,
60 	VIRTGEOM,
61 	NCYL,
62 	NHEADS,
63 	NSECTPT,
64 	SSIZE,
65 	ACYL
66 };
67 
68 enum {
69 	FDISK_MINOR_WRITE = 1,
70 	FDISK_MAJOR_WRITE
71 };
72 
73 #define	FDISK_SECTS_PER_CYL(epp) \
74 	(epp->disk_geom.phys_heads * epp->disk_geom.phys_sec)
75 #define	FDISK_SECT_TO_CYL(epp, x)	((x) / (FDISK_SECTS_PER_CYL(epp)))
76 #define	FDISK_CYL_TO_SECT(epp, x)	((x) * (FDISK_SECTS_PER_CYL(epp)))
77 #define	FDISK_ABS_CYL_NUM(epp, x)	(FDISK_SECT_TO_CYL(x) +\
78     epp->ext_beg_cyl)
79 
80 #define	FDISK_CYL_BNDRY_ALIGN(epp, x)	(((x) % (FDISK_SECTS_PER_CYL(epp))) ? \
81 	(((x)/(FDISK_SECTS_PER_CYL(epp))) + 1) :\
82 	((x)/(FDISK_SECTS_PER_CYL(epp))))
83 
84 /*
85  * Extended partition structure :
86  *  +--------------+
87  *  |+--+          |
88  *  ||  |----------+---> structure at the beginning of the extended partition
89  *  ||--|          |     ( Lets call it the EBR - Extended Boot Record )
90  *  ||  |      +---+--->
91  *  |+--+      |   |     Logical drive within the extended partition
92  *  |+---------+--+|     ( We will plainly call this a logical drive )
93  *  ||            ||
94  *  ||            ||
95  *  ||            ||
96  *  |+------------+|
97  *  +--------------+
98  *
99  *
100  * EBR is effectively "struct ipart parts[2]".
101  * The picture below shows what the EBR contains. The EBR has
102  * two important pieces of information. The first is the offset and the size
103  * of the logical drive in this extended partition. The second is the offset
104  * and size of the next extended partition. The offsets are relative to
105  * beginning of the first extended partition. These extended partitions are
106  * arranged like a linked list.
107  * Note that (currently) only one extended partition can exist in the MBR.
108  * The system ID of a logical drive within the extended partition cannot be
109  * that of an extended partition.
110  *
111  *                   +------+
112  *                   |      |
113  *  +--------------+ |    +-v------------+
114  *  |+--+          | |    |+--+          |
115  *  ||  |---+      | |    ||  |          |
116  *  ||--|   |      | |    ||--|          |
117  *  ||  |---|------+-+    ||  |          |
118  *  |+--+   |      |      |+--+          |
119  *  |+------v-----+|      |+------------+|
120  *  ||            ||      ||            ||
121  *  ||            ||      ||            ||
122  *  ||            ||      ||            ||
123  *  |+------------+|      |+------------+|
124  *  +--------------+      +--------------+
125  *
126  */
127 
128 /*
129  * Main structure used to record changes to the partitions made.
130  * Changes are not written to disk everytime, but maintained in this structure.
131  * This information is used when the user chooses to commit the changes.
132  * A linked list of this structure represents the ondisk partitions.
133  */
134 typedef struct logical_drive {
135 
136 	/* structure holding the EBR data */
137 	struct ipart parts[2];
138 
139 	/*
140 	 * Absolute beginning sector of the extended partition, and hence an
141 	 * indicator of where the EBR for this logical drive would go on disk.
142 	 * NOTE : In case the first logical drive in this extended partition is
143 	 * out of (disk) order, this indicates the beginning of the logical
144 	 * drive. The EBR will anyway be at the first sector of the extended
145 	 * partition, for the first logical drive.
146 	 */
147 	uint32_t abs_secnum;
148 
149 	/*
150 	 * Offset of the logical drive from the beginning of its extended
151 	 * partition
152 	 */
153 	uint32_t logdrive_offset;
154 
155 	/* Size of the logical drive in sectors */
156 	uint32_t numsect;
157 
158 	/* Beginning and ending cylinders of the extended partition */
159 	uint32_t begcyl, endcyl;
160 
161 	/*
162 	 * Flag to indicate if this record is to be sync'ed to disk.
163 	 * It takes two values : FDISK_MAJOR_WRITE and FDISK_MINOR_WRITE
164 	 * If it is a minor write, there is no need to update the information
165 	 * in the kernel structures. Example of a minor write is correction of
166 	 * a corrupt boot signature.
167 	 */
168 	int modified;
169 
170 	/*
171 	 * This pointer points to the next extended partition in the order
172 	 * found on disk.
173 	 */
174 	struct logical_drive *next;
175 
176 	/*
177 	 * This pointer points to the next extended partition in a sorted list
178 	 * sorted in the ascending order of their beginning cylinders.
179 	 */
180 	struct logical_drive *sorted_next;
181 
182 } logical_drive_t;
183 
184 typedef struct fdisk_disk_geom {
185 	ushort_t phys_cyl;
186 	ushort_t phys_sec;
187 	ushort_t phys_heads;
188 	ushort_t alt_cyl;
189 	ushort_t virt_cyl;
190 	ushort_t virt_sec;
191 	ushort_t virt_heads;
192 	ushort_t sectsize;
193 } fdisk_disk_geom_t;
194 
195 typedef struct ext_part
196 {
197 	/* Structure holding geometry information about the device */
198 	fdisk_disk_geom_t disk_geom;
199 
200 	struct ipart *mtable;
201 
202 	char device_name[PATH_MAX];
203 
204 	int dev_fd;
205 
206 	int op_flag;
207 
208 	/*
209 	 * Head of the in memory structure (singly linked list) of extended
210 	 * partition information.
211 	 */
212 	logical_drive_t *ld_head;
213 	logical_drive_t *sorted_ld_head;
214 
215 	/* Beginning cylinder of the extended partition */
216 	uint32_t ext_beg_cyl;
217 
218 	/* Ending cylinder of the extended partition */
219 	uint32_t ext_end_cyl;
220 
221 	/* Beginning sector of the extended partition */
222 	uint32_t ext_beg_sec;
223 
224 	/* Ending sector of the extended partition */
225 	uint32_t ext_end_sec;
226 
227 	/* Count of the number of logical drives in the extended partition */
228 	int logical_drive_count;
229 
230 	/*
231 	 * Flag to keep track of the update to be made to the Extended Boot
232 	 * Record (EBR) when all logical drives are deleted. The EBR is filled
233 	 * with zeroes in such a case.
234 	 */
235 	int first_ebr_is_null;
236 
237 	/*
238 	 * Flag to indicate corrupt logical drives. Can happen when a partition
239 	 * manager creates an extended partition and does not null the first EBR
240 	 * or when important ondisk structures are overwritten by a bad program
241 	 */
242 	int corrupt_logical_drives;
243 
244 	/*
245 	 * The boot block signature 0xAA55 might not be found on some of the
246 	 * EBRs. ( Even though the rest of the data might be good )
247 	 * The following array is used to store the list of such logical drive
248 	 * numbers.
249 	 */
250 	uchar_t invalid_bb_sig[MAX_EXT_PARTS];
251 
252 	/*
253 	 * Can add  a "next" pointer here in case support for multiple
254 	 * extended partitions becomes the standard someday.
255 	 *
256 	 * struct ext_part *next;
257 	 */
258 } ext_part_t;
259 
260 #define	fdisk_get_logical_drive_count(epp) ((epp)->logical_drive_count)
261 #define	fdisk_corrupt_logical_drives(epp) ((epp)->corrupt_logical_drives)
262 #define	fdisk_get_ext_beg_cyl(epp) ((epp)->ext_beg_cyl)
263 #define	fdisk_get_ext_end_cyl(epp) ((epp)->ext_end_cyl)
264 #define	fdisk_get_ext_beg_sec(epp) ((epp)->ext_beg_sec)
265 #define	fdisk_get_ext_end_sec(epp) ((epp)->ext_end_sec)
266 #define	fdisk_get_ld_head(epp) ((epp)->ld_head)
267 #define	fdisk_is_solaris_part(id) (((id) == SUNIXOS) || ((id) == SUNIXOS2))
268 #define	fdisk_is_dos_extended(id) (((id) == EXTDOS) || ((id) == FDISK_EXTLBA))
269 
270 extern int fdisk_is_linux_swap(ext_part_t *epp, uint32_t part_start,
271     uint64_t *lsm_offset);
272 extern int libfdisk_init(ext_part_t **epp, char *devstr, struct ipart *parttab,
273     int opflag);
274 extern int libfdisk_reset(ext_part_t *epp);
275 extern void libfdisk_fini(ext_part_t **epp);
276 extern int fdisk_ext_find_first_free_sec(ext_part_t *epp,
277     uint32_t *first_free_sec);
278 extern uint32_t fdisk_ext_find_last_free_sec(ext_part_t *epp, uint32_t begsec);
279 extern int fdisk_ext_part_exists(ext_part_t *epp);
280 extern int fdisk_validate_logical_drive(ext_part_t *epp, uint32_t begsec,
281     uint32_t offset, uint32_t numsec);
282 extern int fdisk_ext_validate_part_start(ext_part_t *epp, uint32_t begcyl,
283     uint32_t *begsec);
284 extern int fdisk_get_solaris_part(ext_part_t *epp, int *pnum, uint32_t *begsec,
285     uint32_t *numsec);
286 extern int fdisk_get_part_info(ext_part_t *epp, int pnum, uchar_t *sysid,
287     uint32_t *begsec, uint32_t *numsec);
288 extern int fdisk_commit_ext_part(ext_part_t *epp);
289 extern void fdisk_change_logical_drive_id(ext_part_t *epp, int pno,
290     uchar_t partid);
291 extern void fdisk_add_logical_drive(ext_part_t *epp, uint32_t begsec,
292     uint32_t endsec, uchar_t partid);
293 extern void fdisk_delete_logical_drive(ext_part_t *epp, int pno);
294 extern int fdisk_init_ext_part(ext_part_t *epp, uint32_t rsect, uint32_t nsect);
295 extern int fdisk_delete_ext_part(ext_part_t *epp);
296 extern int fdisk_get_disk_geom(ext_part_t *epp, int type, int what);
297 extern int fdisk_invalid_bb_sig(ext_part_t *epp, uchar_t **bbsig_arr);
298 extern int fdisk_mounted_logical_drives(ext_part_t *epp);
299 
300 #ifdef	__cplusplus
301 }
302 #endif
303 
304 #endif /* _LIBFDISK_H_ */
305