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 2007 Sun Microsystems, Inc. All rights reserved.
23 * Use is subject to license terms.
24 */
25
26
27 #ifndef _SYS_LOFI_H
28 #define _SYS_LOFI_H
29
30 #pragma ident "%Z%%M% %I% %E% SMI"
31
32 #include <sys/types.h>
33 #include <sys/time.h>
34 #include <sys/taskq.h>
35 #include <sys/vtoc.h>
36 #include <sys/dkio.h>
37 #include <sys/vnode.h>
38
39 #ifdef __cplusplus
40 extern "C" {
41 #endif
42
43 /*
44 * /dev names:
45 * /dev/lofictl - master control device
46 * /dev/lofi - block devices, named by minor number
47 * /dev/rlofi - character devices, named by minor number
48 */
49 #define LOFI_DRIVER_NAME "lofi"
50 #define LOFI_CTL_NODE "ctl"
51 #define LOFI_CTL_NAME LOFI_DRIVER_NAME LOFI_CTL_NODE
52 #define LOFI_BLOCK_NAME LOFI_DRIVER_NAME
53 #define LOFI_CHAR_NAME "r" LOFI_DRIVER_NAME
54
55 /*
56 *
57 * Use is:
58 * ld = open("/dev/lofictl", O_RDWR | O_EXCL);
59 *
60 * lofi must be opened exclusively. Access is controlled by permissions on
61 * the device, which is 644 by default. Write-access is required for ioctls
62 * that change state, but only read-access is required for the ioctls that
63 * return information. Basically, only root can add and remove files, but
64 * non-root can look at the current lists.
65 *
66 * ioctl usage:
67 *
68 * kernel ioctls
69 *
70 * strcpy(li.li_filename, "somefilename");
71 * ioctl(ld, LOFI_MAP_FILE, &li);
72 * newminor = li.li_minor;
73 *
74 * strcpy(li.li_filename, "somefilename");
75 * ioctl(ld, LOFI_UNMAP_FILE, &li);
76 *
77 * strcpy(li.li_filename, "somefilename");
78 * li.li_minor = minor_number;
79 * ioctl(ld, LOFI_MAP_FILE_MINOR, &li);
80 *
81 * li.li_minor = minor_number;
82 * ioctl(ld, LOFI_UNMAP_FILE_MINOR, &li);
83 *
84 * li.li_minor = minor_number;
85 * ioctl(ld, LOFI_GET_FILENAME, &li);
86 *
87 * strcpy(li.li_filename, "somefilename");
88 * ioctl(ld, LOFI_GET_MINOR, &li);
89 *
90 * li.li_minor = 0;
91 * ioctl(ld, LOFI_GET_MAXMINOR, &li);
92 * maxminor = li.li_minor;
93 *
94 * strcpy(li.li_filename, "somefilename");
95 * li.li_minor = 0;
96 * ioctl(ld, LOFI_CHECK_COMPRESSED, &li);
97 *
98 * If the 'li_force' flag is set for any of the LOFI_UNMAP_* commands, then if
99 * the device is busy, the underlying vnode will be closed, and any subsequent
100 * operations will fail. It will behave as if the device had been forcibly
101 * removed, so the DKIOCSTATE ioctl will return DKIO_DEV_GONE. When the device
102 * is last closed, it will be torn down.
103 *
104 * Oh, and last but not least: these ioctls are totally private and only
105 * for use by lofiadm(1M).
106 *
107 */
108
109 struct lofi_ioctl {
110 uint32_t li_minor;
111 boolean_t li_force;
112 char li_filename[MAXPATHLEN];
113 char li_algorithm[MAXPATHLEN];
114 };
115
116 #define LOFI_IOC_BASE (('L' << 16) | ('F' << 8))
117
118 #define LOFI_MAP_FILE (LOFI_IOC_BASE | 0x01)
119 #define LOFI_MAP_FILE_MINOR (LOFI_IOC_BASE | 0x02)
120 #define LOFI_UNMAP_FILE (LOFI_IOC_BASE | 0x03)
121 #define LOFI_UNMAP_FILE_MINOR (LOFI_IOC_BASE | 0x04)
122 #define LOFI_GET_FILENAME (LOFI_IOC_BASE | 0x05)
123 #define LOFI_GET_MINOR (LOFI_IOC_BASE | 0x06)
124 #define LOFI_GET_MAXMINOR (LOFI_IOC_BASE | 0x07)
125 #define LOFI_CHECK_COMPRESSED (LOFI_IOC_BASE | 0x08)
126
127 /*
128 * file types that might be usable with lofi, maybe. Only regular
129 * files are documented though.
130 */
131 #define S_ISLOFIABLE(mode) \
132 (S_ISREG(mode) || S_ISBLK(mode) || S_ISCHR(mode))
133
134 #define SEGHDR 1
135 #define COMPRESSED 1
136 #define UNCOMPRESSED 0
137
138 #if defined(_KERNEL)
139
140 /*
141 * We limit the maximum number of active lofi devices to 128, which seems very
142 * large. You can tune this by changing lofi_max_files in /etc/system.
143 * If you change it dynamically, which you probably shouldn't do, make sure
144 * to only _increase_ it.
145 */
146 #define LOFI_MAX_FILES 128
147 extern uint32_t lofi_max_files;
148
149 #define V_ISLOFIABLE(vtype) \
150 ((vtype == VREG) || (vtype == VBLK) || (vtype == VCHR))
151
152 struct lofi_state {
153 char *ls_filename; /* filename to open */
154 size_t ls_filename_sz;
155 struct vnode *ls_vp; /* open vnode */
156 kmutex_t ls_vp_lock; /* protects ls_vp */
157 kcondvar_t ls_vp_cv; /* signal changes to ls_vp */
158 uint32_t ls_vp_iocount; /* # pending I/O requests */
159 boolean_t ls_vp_closereq; /* force close requested */
160 u_offset_t ls_vp_size;
161 uint32_t ls_blk_open;
162 uint32_t ls_chr_open;
163 uint32_t ls_lyr_open_count;
164 int ls_openflag;
165 taskq_t *ls_taskq;
166 kstat_t *ls_kstat;
167 kmutex_t ls_kstat_lock;
168 struct dk_geom ls_dkg;
169 struct vtoc ls_vtoc;
170 struct dk_cinfo ls_ci;
171
172 /* the following fields are required for compression support */
173
174 /*
175 * index into lofi_compress_table for the compression algorithm
176 * used
177 */
178 int ls_comp_algorithm_index;
179 uint32_t ls_comp_algorithm_len;
180 /* size of an uncompressed segment */
181 uint32_t ls_uncomp_seg_sz;
182 /* number of index entries */
183 uint32_t ls_comp_index_sz;
184 /* exponent for byte shift, power of 2 */
185 uint32_t ls_comp_seg_shift;
186 /*
187 * size of the last uncompressed segment (the file may
188 * not be an exact multiple of the segment size ls_uncomp_seg_sz)
189 */
190 uint32_t ls_uncomp_last_seg_sz;
191 /*
192 * the offset in the file where the header ends and the
193 * actual compressed data begins. The segment offsets in
194 * the index do not account for the header so this value must
195 * be added
196 */
197 uint64_t ls_comp_offbase;
198 /*
199 * the array holding the segment index. This is a pointer
200 * into ls_comp_index_data
201 */
202 uint64_t *ls_comp_seg_index;
203 /*
204 * holds the index pages loaded from the file. This is aligned
205 * on a disk block boundary so lsecomp_seg_index above is used
206 * to point to the actual array
207 */
208 caddr_t ls_comp_index_data;
209 /* size of ls_comp_index_data */
210 uint32_t ls_comp_index_data_sz;
211 /*
212 * incase of compressed files, ls_vp_size above is
213 * tweaked to represent the actual uncompressed file
214 * size so that fake_disk_geometry gives the correct
215 * values. However we need the actual compressed file
216 * size while faulting in pages from the compressed
217 * file in lofi_mapped_rdwr
218 */
219 u_offset_t ls_vp_comp_size;
220 };
221
222 #endif /* _KERNEL */
223
224 /*
225 * Common signature for all lofi compress functions
226 */
227 typedef int lofi_compress_func_t(void *src, size_t srclen, void *dst,
228 size_t *destlen, int level);
229
230 /*
231 * Information about each compression function
232 */
233 typedef struct lofi_compress_info {
234 lofi_compress_func_t *l_decompress;
235 lofi_compress_func_t *l_compress;
236 int l_level;
237 char *l_name; /* algorithm name */
238 } lofi_compress_info_t;
239
240 enum lofi_compress {
241 LOFI_COMPRESS_GZIP = 0,
242 LOFI_COMPRESS_GZIP_6 = 1,
243 LOFI_COMPRESS_GZIP_9 = 2,
244 LOFI_COMPRESS_FUNCTIONS
245 };
246
247 #ifdef __cplusplus
248 }
249 #endif
250
251 #endif /* _SYS_LOFI_H */