Commit | Line | Data |
---|---|---|
975fab17 JW |
1 | /* |
2 | * Common helper functions for kprobes and uprobes | |
3 | * | |
4 | * Copyright IBM Corp. 2014 | |
5 | */ | |
6 | ||
d6fe5be3 | 7 | #include <asm/kprobes.h> |
975fab17 JW |
8 | #include <asm/dis.h> |
9 | ||
10 | int probe_is_prohibited_opcode(u16 *insn) | |
11 | { | |
12 | if (!is_known_insn((unsigned char *)insn)) | |
13 | return -EINVAL; | |
14 | switch (insn[0] >> 8) { | |
15 | case 0x0c: /* bassm */ | |
16 | case 0x0b: /* bsm */ | |
17 | case 0x83: /* diag */ | |
18 | case 0x44: /* ex */ | |
19 | case 0xac: /* stnsm */ | |
20 | case 0xad: /* stosm */ | |
21 | return -EINVAL; | |
22 | case 0xc6: | |
23 | switch (insn[0] & 0x0f) { | |
24 | case 0x00: /* exrl */ | |
25 | return -EINVAL; | |
26 | } | |
27 | } | |
28 | switch (insn[0]) { | |
29 | case 0x0101: /* pr */ | |
30 | case 0xb25a: /* bsa */ | |
31 | case 0xb240: /* bakr */ | |
32 | case 0xb258: /* bsg */ | |
33 | case 0xb218: /* pc */ | |
34 | case 0xb228: /* pt */ | |
35 | case 0xb98d: /* epsw */ | |
36 | case 0xe560: /* tbegin */ | |
37 | case 0xe561: /* tbeginc */ | |
38 | case 0xb2f8: /* tend */ | |
39 | return -EINVAL; | |
40 | } | |
41 | return 0; | |
42 | } | |
43 | ||
44 | int probe_get_fixup_type(u16 *insn) | |
45 | { | |
46 | /* default fixup method */ | |
47 | int fixup = FIXUP_PSW_NORMAL; | |
48 | ||
49 | switch (insn[0] >> 8) { | |
50 | case 0x05: /* balr */ | |
51 | case 0x0d: /* basr */ | |
52 | fixup = FIXUP_RETURN_REGISTER; | |
53 | /* if r2 = 0, no branch will be taken */ | |
54 | if ((insn[0] & 0x0f) == 0) | |
55 | fixup |= FIXUP_BRANCH_NOT_TAKEN; | |
56 | break; | |
57 | case 0x06: /* bctr */ | |
58 | case 0x07: /* bcr */ | |
59 | fixup = FIXUP_BRANCH_NOT_TAKEN; | |
60 | break; | |
61 | case 0x45: /* bal */ | |
62 | case 0x4d: /* bas */ | |
63 | fixup = FIXUP_RETURN_REGISTER; | |
64 | break; | |
65 | case 0x47: /* bc */ | |
66 | case 0x46: /* bct */ | |
67 | case 0x86: /* bxh */ | |
68 | case 0x87: /* bxle */ | |
69 | fixup = FIXUP_BRANCH_NOT_TAKEN; | |
70 | break; | |
71 | case 0x82: /* lpsw */ | |
72 | fixup = FIXUP_NOT_REQUIRED; | |
73 | break; | |
74 | case 0xb2: /* lpswe */ | |
75 | if ((insn[0] & 0xff) == 0xb2) | |
76 | fixup = FIXUP_NOT_REQUIRED; | |
77 | break; | |
78 | case 0xa7: /* bras */ | |
79 | if ((insn[0] & 0x0f) == 0x05) | |
80 | fixup |= FIXUP_RETURN_REGISTER; | |
81 | break; | |
82 | case 0xc0: | |
83 | if ((insn[0] & 0x0f) == 0x05) /* brasl */ | |
84 | fixup |= FIXUP_RETURN_REGISTER; | |
85 | break; | |
86 | case 0xeb: | |
87 | switch (insn[2] & 0xff) { | |
88 | case 0x44: /* bxhg */ | |
89 | case 0x45: /* bxleg */ | |
90 | fixup = FIXUP_BRANCH_NOT_TAKEN; | |
91 | break; | |
92 | } | |
93 | break; | |
94 | case 0xe3: /* bctg */ | |
95 | if ((insn[2] & 0xff) == 0x46) | |
96 | fixup = FIXUP_BRANCH_NOT_TAKEN; | |
97 | break; | |
98 | case 0xec: | |
99 | switch (insn[2] & 0xff) { | |
100 | case 0xe5: /* clgrb */ | |
101 | case 0xe6: /* cgrb */ | |
102 | case 0xf6: /* crb */ | |
103 | case 0xf7: /* clrb */ | |
104 | case 0xfc: /* cgib */ | |
105 | case 0xfd: /* cglib */ | |
106 | case 0xfe: /* cib */ | |
107 | case 0xff: /* clib */ | |
108 | fixup = FIXUP_BRANCH_NOT_TAKEN; | |
109 | break; | |
110 | } | |
111 | break; | |
112 | } | |
113 | return fixup; | |
114 | } | |
115 | ||
116 | int probe_is_insn_relative_long(u16 *insn) | |
117 | { | |
118 | /* Check if we have a RIL-b or RIL-c format instruction which | |
119 | * we need to modify in order to avoid instruction emulation. */ | |
120 | switch (insn[0] >> 8) { | |
121 | case 0xc0: | |
122 | if ((insn[0] & 0x0f) == 0x00) /* larl */ | |
123 | return true; | |
124 | break; | |
125 | case 0xc4: | |
126 | switch (insn[0] & 0x0f) { | |
127 | case 0x02: /* llhrl */ | |
128 | case 0x04: /* lghrl */ | |
129 | case 0x05: /* lhrl */ | |
130 | case 0x06: /* llghrl */ | |
131 | case 0x07: /* sthrl */ | |
132 | case 0x08: /* lgrl */ | |
133 | case 0x0b: /* stgrl */ | |
134 | case 0x0c: /* lgfrl */ | |
135 | case 0x0d: /* lrl */ | |
136 | case 0x0e: /* llgfrl */ | |
137 | case 0x0f: /* strl */ | |
138 | return true; | |
139 | } | |
140 | break; | |
141 | case 0xc6: | |
142 | switch (insn[0] & 0x0f) { | |
143 | case 0x02: /* pfdrl */ | |
144 | case 0x04: /* cghrl */ | |
145 | case 0x05: /* chrl */ | |
146 | case 0x06: /* clghrl */ | |
147 | case 0x07: /* clhrl */ | |
148 | case 0x08: /* cgrl */ | |
149 | case 0x0a: /* clgrl */ | |
150 | case 0x0c: /* cgfrl */ | |
151 | case 0x0d: /* crl */ | |
152 | case 0x0e: /* clgfrl */ | |
153 | case 0x0f: /* clrl */ | |
154 | return true; | |
155 | } | |
156 | break; | |
157 | } | |
158 | return false; | |
159 | } |