xref: /freebsd/stand/userboot/userboot.h (revision b3e76948)
1 /*-
2  * Copyright (c) 2011 Doug Rabson
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 /*
28  * USERBOOT interface versions
29  */
30 #define	USERBOOT_VERSION_1      1
31 #define	USERBOOT_VERSION_2      2
32 #define	USERBOOT_VERSION_3      3
33 
34 /*
35  * Version 4 added more generic callbacks for setting up
36  * registers and descriptors. The callback structure is
37  * backward compatible (new callbacks have been added at
38  * the tail end).
39  */
40 #define	USERBOOT_VERSION_4      4
41 
42 /*
43  * Version 5 added a callback for indicating that the guest
44  * should be restarted with a different interpreter.  The callback
45  * structure is still backward compatible.
46  */
47 #define	USERBOOT_VERSION_5      5
48 
49 /*
50  * Exit codes from the loader
51  */
52 #define	USERBOOT_EXIT_QUIT      1
53 #define	USERBOOT_EXIT_REBOOT    2
54 
55 struct loader_callbacks {
56 	/*
57 	 * Console i/o
58 	 */
59 
60         /*
61          * Wait until a key is pressed on the console and then return it
62          */
63 	int		(*getc)(void *arg);
64 
65         /*
66          * Write the character ch to the console
67          */
68 	void		(*putc)(void *arg, int ch);
69 
70         /*
71          * Return non-zero if a key can be read from the console
72          */
73 	int		(*poll)(void *arg);
74 
75 	/*
76 	 * Host filesystem i/o
77 	 */
78 
79         /*
80          * Open a file in the host filesystem
81          */
82 	int		(*open)(void *arg, const char *filename, void **h_return);
83 
84         /*
85          * Close a file
86          */
87 	int		(*close)(void *arg, void *h);
88 
89         /*
90          * Return non-zero if the file is a directory
91          */
92 	int		(*isdir)(void *arg, void *h);
93 
94         /*
95          * Read size bytes from a file. The number of bytes remaining
96          * in dst after reading is returned in *resid_return
97          */
98 	int		(*read)(void *arg, void *h, void *dst, size_t size,
99             size_t *resid_return);
100 
101         /*
102          * Read an entry from a directory. The entry's inode number is
103          * returned in *fileno_return, its type in *type_return and
104          * the name length in *namelen_return. The name itself is
105          * copied to the buffer name which must be at least PATH_MAX
106          * in size.
107          */
108 	int		(*readdir)(void *arg, void *h, uint32_t *fileno_return,
109             uint8_t *type_return, size_t *namelen_return, char *name);
110 
111         /*
112          * Seek to a location within an open file
113          */
114 	int		(*seek)(void *arg, void *h, uint64_t offset,
115             int whence);
116 
117         /*
118          * Return some stat(2) related information about the file
119          */
120 	int		(*stat)(void *arg, void *h, struct stat *stp);
121 
122 	/*
123 	 * Disk image i/o
124 	 */
125 
126         /*
127          * Read from a disk image at the given offset
128          */
129 	int		(*diskread)(void *arg, int unit, uint64_t offset,
130             void *dst, size_t size, size_t *resid_return);
131 
132         /*
133          * Write to a disk image at the given offset
134          */
135 	int		(*diskwrite)(void *arg, int unit, uint64_t offset,
136             void *src, size_t size, size_t *resid_return);
137 
138 	/*
139 	 * Guest virtual machine i/o
140 	 */
141 
142         /*
143          * Copy to the guest address space
144          */
145 	int		(*copyin)(void *arg, const void *from,
146             uint64_t to, size_t size);
147 
148         /*
149          * Copy from the guest address space
150          */
151 	int		(*copyout)(void *arg, uint64_t from,
152             void *to, size_t size);
153 
154         /*
155          * Set a guest register value
156          */
157 	void		(*setreg)(void *arg, int, uint64_t);
158 
159         /*
160          * Set a guest MSR value
161          */
162 	void		(*setmsr)(void *arg, int, uint64_t);
163 
164         /*
165          * Set a guest CR value
166          */
167 	void		(*setcr)(void *arg, int, uint64_t);
168 
169         /*
170          * Set the guest GDT address
171          */
172         void            (*setgdt)(void *arg, uint64_t, size_t);
173 
174         /*
175          * Transfer control to the guest at the given address
176          */
177 	void		(*exec)(void *arg, uint64_t pc);
178 
179 	/*
180 	 * Misc
181 	 */
182 
183         /*
184          * Sleep for usec microseconds
185          */
186 	void		(*delay)(void *arg, int usec);
187 
188         /*
189          * Exit with the given exit code
190          */
191 	void		(*exit)(void *arg, int v);
192 
193         /*
194          * Return guest physical memory map details
195          */
196 	void		(*getmem)(void *arg, uint64_t *lowmem,
197             uint64_t *highmem);
198 
199 	/*
200 	 * ioctl interface to the disk device
201 	 */
202 	int		(*diskioctl)(void *arg, int unit, u_long cmd,
203 	    void *data);
204 
205 	/*
206 	 * Returns an environment variable in the form "name=value".
207 	 *
208 	 * If there are no more variables that need to be set in the
209 	 * loader environment then return NULL.
210 	 *
211 	 * 'num' is used as a handle for the callback to identify which
212 	 * environment variable to return next. It will begin at 0 and
213 	 * each invocation will add 1 to the previous value of 'num'.
214 	 */
215 	char *		(*getenv)(void *arg, int num);
216 
217 	/*
218 	 * Version 4 additions.
219 	 */
220 	int	(*vm_set_register)(void *arg, int vcpu, int reg, uint64_t val);
221 	int	(*vm_set_desc)(void *arg, int vcpu, int reg, uint64_t base,
222 	    u_int limit, u_int access);
223 
224 	/*
225 	 * Version 5 addition.
226 	 */
227 	void	(*swap_interpreter)(void *arg, const char *interp);
228 };
229