xref: /openbmc/linux/fs/isofs/rock.h (revision 12eb4683)
1 /*
2  * These structs are used by the system-use-sharing protocol, in which the
3  * Rock Ridge extensions are embedded.  It is quite possible that other
4  * extensions are present on the disk, and this is fine as long as they
5  * all use SUSP
6  */
7 
8 struct SU_SP_s {
9 	unsigned char magic[2];
10 	unsigned char skip;
11 } __attribute__ ((packed));
12 
13 struct SU_CE_s {
14 	char extent[8];
15 	char offset[8];
16 	char size[8];
17 };
18 
19 struct SU_ER_s {
20 	unsigned char len_id;
21 	unsigned char len_des;
22 	unsigned char len_src;
23 	unsigned char ext_ver;
24 	char data[0];
25 } __attribute__ ((packed));
26 
27 struct RR_RR_s {
28 	char flags[1];
29 } __attribute__ ((packed));
30 
31 struct RR_PX_s {
32 	char mode[8];
33 	char n_links[8];
34 	char uid[8];
35 	char gid[8];
36 };
37 
38 struct RR_PN_s {
39 	char dev_high[8];
40 	char dev_low[8];
41 };
42 
43 struct SL_component {
44 	unsigned char flags;
45 	unsigned char len;
46 	char text[0];
47 } __attribute__ ((packed));
48 
49 struct RR_SL_s {
50 	unsigned char flags;
51 	struct SL_component link;
52 } __attribute__ ((packed));
53 
54 struct RR_NM_s {
55 	unsigned char flags;
56 	char name[0];
57 } __attribute__ ((packed));
58 
59 struct RR_CL_s {
60 	char location[8];
61 };
62 
63 struct RR_PL_s {
64 	char location[8];
65 };
66 
67 struct stamp {
68 	char time[7];
69 } __attribute__ ((packed));
70 
71 struct RR_TF_s {
72 	char flags;
73 	struct stamp times[0];	/* Variable number of these beasts */
74 } __attribute__ ((packed));
75 
76 /* Linux-specific extension for transparent decompression */
77 struct RR_ZF_s {
78 	char algorithm[2];
79 	char parms[2];
80 	char real_size[8];
81 };
82 
83 /*
84  * These are the bits and their meanings for flags in the TF structure.
85  */
86 #define TF_CREATE 1
87 #define TF_MODIFY 2
88 #define TF_ACCESS 4
89 #define TF_ATTRIBUTES 8
90 #define TF_BACKUP 16
91 #define TF_EXPIRATION 32
92 #define TF_EFFECTIVE 64
93 #define TF_LONG_FORM 128
94 
95 struct rock_ridge {
96 	char signature[2];
97 	unsigned char len;
98 	unsigned char version;
99 	union {
100 		struct SU_SP_s SP;
101 		struct SU_CE_s CE;
102 		struct SU_ER_s ER;
103 		struct RR_RR_s RR;
104 		struct RR_PX_s PX;
105 		struct RR_PN_s PN;
106 		struct RR_SL_s SL;
107 		struct RR_NM_s NM;
108 		struct RR_CL_s CL;
109 		struct RR_PL_s PL;
110 		struct RR_TF_s TF;
111 		struct RR_ZF_s ZF;
112 	} u;
113 };
114 
115 #define RR_PX 1			/* POSIX attributes */
116 #define RR_PN 2			/* POSIX devices */
117 #define RR_SL 4			/* Symbolic link */
118 #define RR_NM 8			/* Alternate Name */
119 #define RR_CL 16		/* Child link */
120 #define RR_PL 32		/* Parent link */
121 #define RR_RE 64		/* Relocation directory */
122 #define RR_TF 128		/* Timestamps */
123