xref: /titanic_41/usr/src/uts/sparc/krtld/doreloc.c (revision efd31e1d839d4665462b5c267a1c654548082663)
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 /*
23  * Copyright (c) 1995, 2010, Oracle and/or its affiliates. All rights reserved.
24  */
25 
26 #if	defined(_KERNEL)
27 #include	<sys/types.h>
28 #include	"krtld/reloc.h"
29 #else
30 #define	ELF_TARGET_SPARC
31 #if defined(DO_RELOC_LIBLD)
32 #undef DO_RELOC_LIBLD
33 #define	DO_RELOC_LIBLD_SPARC
34 #endif
35 #include	<stdio.h>
36 #include	"sgs.h"
37 #include	"machdep.h"
38 #include	"libld.h"
39 #include	"reloc.h"
40 #include	"conv.h"
41 #include	"msg.h"
42 #endif
43 
44 /*
45  * We need to build this code differently when it is used for
46  * cross linking:
47  *	- Data alignment requirements can differ from those
48  *		of the running system, so we can't access data
49  *		in units larger than a byte
50  *	- We have to include code to do byte swapping when the
51  *		target and linker host use different byte ordering,
52  *		but such code is a waste when running natively.
53  */
54 #if !defined(DO_RELOC_LIBLD) || defined(__sparc)
55 #define	DORELOC_NATIVE
56 #endif
57 
58 /*
59  * This table represents the current relocations that do_reloc() is able to
60  * process.  The relocations below that are marked SPECIAL are relocations that
61  * take special processing and shouldn't actually ever be passed to do_reloc().
62  */
63 const Rel_entry reloc_table[R_SPARC_NUM] = {
64 /* R_SPARC_NONE */	{0x0, FLG_RE_NOTREL, 0, 0, 0},
65 /* R_SPARC_8 */		{0x0, FLG_RE_VERIFY, 1, 0, 0},
66 /* R_SPARC_16 */	{0x0, FLG_RE_VERIFY, 2, 0, 0},
67 /* R_SPARC_32 */	{0x0, FLG_RE_VERIFY, 4, 0, 0},
68 /* R_SPARC_DISP8 */	{0x0, FLG_RE_PCREL | FLG_RE_VERIFY | FLG_RE_SIGN,
69 				1, 0, 0},
70 /* R_SPARC_DISP16 */	{0x0, FLG_RE_PCREL | FLG_RE_VERIFY | FLG_RE_SIGN,
71 				2, 0, 0},
72 /* R_SPARC_DISP32 */	{0x0, FLG_RE_PCREL | FLG_RE_VERIFY | FLG_RE_SIGN,
73 				4, 0, 0},
74 /* R_SPARC_WDISP30 */	{0x0, FLG_RE_PCREL | FLG_RE_VERIFY | FLG_RE_SIGN,
75 				4, 2, 30},
76 /* R_SPARC_WDISP22 */	{0x0, FLG_RE_PCREL | FLG_RE_VERIFY | FLG_RE_SIGN,
77 				4, 2, 22},
78 #if	defined(_ELF64)
79 /* R_SPARC_HI22 */	{0x0, FLG_RE_VERIFY, 4, 10, 22},
80 #else
81 /* R_SPARC_HI22 */	{0x0, FLG_RE_NOTREL, 4, 10, 22},
82 #endif
83 /* R_SPARC_22 */	{0x0, FLG_RE_VERIFY, 4, 0, 22},
84 /* R_SPARC_13 */	{0x0, FLG_RE_VERIFY | FLG_RE_SIGN, 4, 0, 13},
85 /* R_SPARC_LO10 */	{0x3ff, FLG_RE_SIGN, 4, 0, 13},
86 /* R_SPARC_GOT10 */	{0x3ff, FLG_RE_GOTADD | FLG_RE_SIGN, 4, 0, 13},
87 /* R_SPARC_GOT13 */	{0x0, FLG_RE_GOTADD | FLG_RE_VERIFY | FLG_RE_SIGN,
88 				4, 0, 13},
89 /* R_SPARC_GOT22 */	{0x0, FLG_RE_GOTADD, 4, 10, 22},
90 /* R_SPARC_PC10 */	{0x3ff, FLG_RE_PCREL | FLG_RE_SIGN | FLG_RE_LOCLBND,
91 				4, 0, 13},
92 /* R_SPARC_PC22 */	{0x0, FLG_RE_PCREL | FLG_RE_SIGN | FLG_RE_VERIFY |
93 				FLG_RE_LOCLBND, 4, 10, 22},
94 /* R_SPARC_WPLT30 */	{0x0, FLG_RE_PCREL | FLG_RE_PLTREL |
95 				FLG_RE_VERIFY | FLG_RE_SIGN,
96 				4, 2, 30},
97 /* R_SPARC_COPY */	{0x0, 0, 0, 0, 0},		/* SPECIAL */
98 #if	defined(_ELF64)
99 /* R_SPARC_GLOB_DAT */	{0x0, FLG_RE_NOTREL, 8, 0, 0},
100 #else
101 /* R_SPARC_GLOB_DAT */	{0x0, FLG_RE_NOTREL, 4, 0, 0},
102 #endif
103 /* R_SPARC_JMP_SLOT */	{0x0, 0, 0, 0, 0},		/* SPECIAL */
104 #if	defined(_ELF64)
105 /* R_SPARC_RELATIVE */	{0x0, FLG_RE_NOTREL, 8, 0, 0},
106 #else
107 /* R_SPARC_RELATIVE */	{0x0, FLG_RE_NOTREL, 4, 0, 0},
108 #endif
109 /* R_SPARC_UA32 */	{0x0, FLG_RE_UNALIGN, 4, 0, 0},
110 /* R_SPARC_PLT32 */	{0x0, FLG_RE_PLTREL | FLG_RE_VERIFY |
111 				FLG_RE_ADDRELATIVE, 4, 0, 0},
112 /* R_SPARC_HIPLT22 */	{0x0, FLG_RE_PLTREL, 4, 10, 22},
113 /* R_SPARC_LOPLT10 */	{0x3ff, FLG_RE_PLTREL, 4, 0, 13},
114 /* R_SPARC_PCPLT32 */	{0x0, FLG_RE_PLTREL | FLG_RE_PCREL | FLG_RE_VERIFY,
115 				4, 0, 0},
116 /* R_SPARC_PCPLT22 */	{0x0, FLG_RE_PLTREL | FLG_RE_PCREL | FLG_RE_VERIFY,
117 				4, 10, 22},
118 /* R_SPARC_PCPLT10 */	{0x3ff, FLG_RE_PLTREL | FLG_RE_PCREL | FLG_RE_VERIFY,
119 				4, 0, 13},
120 /* R_SPARC_10 */	{0x0, FLG_RE_VERIFY | FLG_RE_SIGN, 4, 0, 10},
121 /* R_SPARC_11 */	{0x0, FLG_RE_VERIFY | FLG_RE_SIGN, 4, 0, 11},
122 /* R_SPARC_64 */	{0x0, FLG_RE_VERIFY, 8, 0, 0},		/* V9 */
123 /* R_SPARC_OLO10 */	{0x3ff, FLG_RE_EXTOFFSET | FLG_RE_SIGN,
124 				4, 0, 13},			/* V9 */
125 /* R_SPARC_HH22 */	{0x0, FLG_RE_VERIFY, 4, 42, 22},	/* V9 */
126 /* R_SPARC_HM10 */	{0x3ff, FLG_RE_SIGN, 4, 32, 13},	/* V9 */
127 /* R_SPARC_LM22 */	{0x0, FLG_RE_NOTREL, 4, 10, 22},	/* V9 */
128 /* R_SPARC_PC_HH22 */	{0x0, FLG_RE_PCREL | FLG_RE_VERIFY,
129 				4, 42, 22},			/* V9 */
130 /* R_SPARC_PC_HM10 */	{0x3ff, FLG_RE_PCREL | FLG_RE_SIGN,
131 				4, 32, 13},			/* V9 */
132 /* R_SPARC_PC_LM22 */	{0x0, FLG_RE_PCREL,
133 				4, 10, 22},			/* V9 */
134 /* R_SPARC_WDISP16 */	{0x0, FLG_RE_PCREL | FLG_RE_WDISP16 |
135 				FLG_RE_VERIFY | FLG_RE_SIGN,
136 				4, 2, 16},
137 /* R_SPARC_WDISP19 */	{0x0, FLG_RE_PCREL | FLG_RE_VERIFY | FLG_RE_SIGN,
138 				4, 2, 19},
139 /* R_SPARC_GLOB_JMP */	{0x0, 0, 0, 0, 0},	/* V9 - not implemented */
140 						/* removed from v9 ABI */
141 /* R_SPARC_7 */		{0x0, FLG_RE_NOTREL, 4, 0, 7},
142 /* R_SPARC_5 */		{0x0, FLG_RE_NOTREL, 4, 0, 5},
143 /* R_SPARC_6 */		{0x0, FLG_RE_NOTREL, 4, 0, 6},
144 /* R_SPARC_DISP64 */	{0x0, FLG_RE_PCREL | FLG_RE_VERIFY | FLG_RE_SIGN,
145 				8, 0, 0},
146 /* R_SPARC_PLT64 */	{0x0, FLG_RE_PLTREL | FLG_RE_VERIFY |
147 				FLG_RE_ADDRELATIVE, 8, 0, 0},
148 /* R_SPARC_HIX22 */	{(Xword)(-1LL), FLG_RE_VERIFY,
149 				4, 10, 22},			/* V9 - HaL */
150 /* R_SPARC_LOX10 */	{0x3ff, FLG_RE_SIGN, 4, 0, 13},		/* V9 - HaL */
151 /* R_SPARC_H44 */	{0x0, FLG_RE_VERIFY, 4, 22, 22},	/* V9 */
152 /* R_SPARC_M44 */	{0x3ff, FLG_RE_NOTREL, 4, 12, 10},	/* V9 */
153 /* R_SPARC_L44 */	{0xfff, FLG_RE_NOTREL, 4, 0, 13},	/* V9 */
154 /* R_SPARC_REGISTER */	{0x0, FLG_RE_REGISTER, 0, 0, 0},	/* SPECIAL */
155 /* R_SPARC_UA64 */	{0x0, FLG_RE_VERIFY | FLG_RE_UNALIGN,
156 				8, 0, 0},			/* V9 */
157 /* R_SPARC_UA16 */	{0x0, FLG_RE_VERIFY | FLG_RE_UNALIGN,
158 				2, 0, 0},
159 /* R_SPARC_TLS_GD_HI22 */   {0x0, FLG_RE_GOTADD | FLG_RE_TLSGD, 4, 10, 22},
160 /* R_SPARC_TLS_GD_LO10 */   {0x3ff, FLG_RE_GOTADD | FLG_RE_TLSGD |
161 				FLG_RE_SIGN, 4, 0, 13},
162 /* R_SPARC_TLS_GD_ADD */    {0x0, FLG_RE_TLSGD, 0, 0, 0},
163 /* R_SPARC_TLS_GD_CALL */   {0x0, FLG_RE_TLSGD, 0, 0, 0},
164 /* R_SPARC_TLS_LDM_HI22 */  {0x0, FLG_RE_GOTADD | FLG_RE_TLSLD, 4, 10, 22},
165 /* R_SPARC_TLS_LDM_LO10 */  {0x3ff, FLG_RE_GOTADD | FLG_RE_TLSLD |
166 				FLG_RE_SIGN, 4, 0, 13},
167 /* R_SPARC_TLS_LDM_ADD */   {0x0, FLG_RE_TLSLD, 0, 0, 0},
168 /* R_SPARC_TLS_LDM_CALL */  {0x0, FLG_RE_TLSLD, 0, 0, 0},
169 /* R_SPARC_TLS_LDO_HIX22 */ {0x0, FLG_RE_VERIFY | FLG_RE_TLSLD, 4, 10, 22},
170 /* R_SPARC_TLS_LDO_LOX10 */ {0x3ff, FLG_RE_SIGN | FLG_RE_TLSLD, 4, 0, 13},
171 /* R_SPARC_TLS_LDO_ADD */   {0x0, FLG_RE_TLSLD, 0, 0, 0},
172 /* R_SPARC_TLS_IE_HI22 */   {0x0, FLG_RE_GOTADD | FLG_RE_TLSIE, 4, 10, 22},
173 /* R_SPARC_TLS_IE_LO10 */   {0x3ff, FLG_RE_GOTADD | FLG_RE_TLSIE |
174 				FLG_RE_SIGN, 4, 0, 13},
175 /* R_SPARC_TLS_IE_LD */	    {0x0, FLG_RE_TLSIE, 0, 0, 0},
176 /* R_SPARC_TLS_IE_LDX */    {0x0, FLG_RE_TLSIE, 0, 0, 0},
177 /* R_SPARC_TLS_IE_ADD */    {0x0, FLG_RE_TLSIE, 0, 0, 0},
178 /* R_SPARC_TLS_LE_HIX22 */  {(Xword)(-1LL),
179 				FLG_RE_VERIFY | FLG_RE_TLSLE, 4, 10, 22},
180 /* R_SPARC_TLS_LE_LOX10 */  {0x3ff, FLG_RE_SIGN | FLG_RE_TLSLE, 4, 0, 13},
181 /* R_SPARC_TLS_DTPMOD32 */  {0x0, FLG_RE_NOTREL, 4, 0, 0},
182 /* R_SPARC_TLS_DTPMOD64 */  {0x0, FLG_RE_NOTREL, 8, 0, 0},
183 /* R_SPARC_TLS_DTPOFF32 */  {0x0, FLG_RE_NOTREL, 4, 0, 0},
184 /* R_SPARC_TLS_DTPOFF64 */  {0x0, FLG_RE_NOTREL, 8, 0, 0},
185 /* R_SPARC_TLS_TPOFF32 */   {0x0, FLG_RE_NOTREL, 4, 0, 0},
186 /* R_SPARC_TLS_TPOFF64 */   {0x0, FLG_RE_NOTREL, 8, 0, 0},
187 /* R_SPARC_GOTDATA_HIX22 */	{0, FLG_RE_SIGN | FLG_RE_GOTREL |
188 					FLG_RE_VERIFY, 4, 10, 22},
189 /* R_SPARC_GOTDATA_LOX10 */	{ 0x3ff, FLG_RE_GOTREL | FLG_RE_SIGN, 4, 0, 13},
190 /* R_SPARC_GOTDATA_OP_HIX22 */	{ 0x0, FLG_RE_GOTOPINS | FLG_RE_GOTADD,
191 					4, 10, 22},
192 /* R_SPARC_GOTDATA_OP_LOX10 */	{ 0x3ff, FLG_RE_SIGN | FLG_RE_GOTOPINS |
193 					FLG_RE_GOTADD, 4, 0, 13},
194 /* R_SPARC_GOTDATA_OP */	{ 0x0, FLG_RE_GOTOPINS, 0, 0, 0},
195 /* R_SPARC_H34 */	{0x0, FLG_RE_VERIFY, 4, 12, 22},	/* V9 */
196 /* R_SPARC_SIZE32 */	{0x0, FLG_RE_SIZE | FLG_RE_VERIFY, 4, 0, 0},
197 /* R_SPARC_SIZE64 */	{0x0, FLG_RE_SIZE | FLG_RE_VERIFY, 8, 0, 0},
198 };
199 
200 
201 /*
202  * Write a single relocated value to its reference location.
203  * We assume we wish to add the relocation amount, value, to the
204  * value of the address already present in the instruction.
205  *
206  * NAME			 VALUE	FIELD		CALCULATION
207  *
208  * R_SPARC_NONE		     0	none		none
209  * R_SPARC_8		     1	V-byte8		S + A
210  * R_SPARC_16		     2	V-half16	S + A
211  * R_SPARC_32		     3	V-word32	S + A
212  * R_SPARC_DISP8	     4	V-byte8		S + A - P
213  * R_SPARC_DISP16	     5	V-half16	S + A - P
214  * R_SPARC_DISP32	     6	V-word32	S + A - P
215  * R_SPARC_WDISP30	     7	V-disp30	(S + A - P) >> 2
216  * R_SPARC_WDISP22	     8	V-disp22	(S + A - P) >> 2
217  * R_SPARC_HI22		     9	T-imm22		(S + A) >> 10
218  * R_SPARC_22		    10	V-imm22		S + A
219  * R_SPARC_13		    11	V-simm13	S + A
220  * R_SPARC_LO10		    12	T-simm13	(S + A) & 0x3ff
221  * R_SPARC_GOT10	    13	T-simm13	G & 0x3ff
222  * R_SPARC_GOT13	    14	V-simm13	G
223  * R_SPARC_GOT22	    15	T-imm22		G >> 10
224  * R_SPARC_PC10		    16	T-simm13	(S + A - P) & 0x3ff
225  * R_SPARC_PC22		    17	V-disp22	(S + A - P) >> 10
226  * R_SPARC_WPLT30	    18	V-disp30	(L + A - P) >> 2
227  * R_SPARC_COPY		    19	none		none
228  * R_SPARC_GLOB_DAT	    20	V-word32	S + A
229  * R_SPARC_JMP_SLOT	    21	V-plt22		S + A
230  * R_SPARC_RELATIVE	    22	V-word32	S + A
231  * R_SPARC_UA32		    23	V-word32	S + A
232  * R_SPARC_PLT32	    24	V-word32        L + A
233  * R_SPARC_HIPLT22	    25	T-imm22         (L + A) >> 10
234  * R_SPARC_LOPLT10	    26	T-simm13        (L + A) & 0x3ff
235  * R_SPARC_PCPLT32	    27	V-word32        L + A - P
236  * R_SPARC_PCPLT22	    28	V-disp22        (L + A - P) >> 10
237  * R_SPARC_PCPLT10	    29	V-simm13        (L + A - P) & 0x3ff
238  * R_SPARC_10		    30	V-simm10	S + A
239  * R_SPARC_11		    31	V-simm11	S + A
240  * R_SPARC_64		    32	V-xword64	S + A
241  * R_SPARC_OLO10	    33	V-simm13	((S + A) & 0x3ff) + O
242  * R_SPARC_HH22		    34	V-imm22		(S + A) >> 42
243  * R_SPARC_HM10		    35	T-simm13	((S + A) >> 32) & 0x3ff
244  * R_SPARC_LM22		    36	T-imm22		(S + A) >> 10
245  * R_SPARC_PC_HH22	    37	V-imm22		(S + A - P) >> 42
246  * R_SPARC_PC_HM10	    38	T-simm13	((S + A - P) >> 32) & 0x3ff
247  * R_SPARC_PC_LM22	    39	T-imm22		(S + A - P) >> 10
248  * R_SPARC_WDISP16	    40	V-d2/disp14	(S + A - P) >> 2
249  * R_SPARC_WDISP19	    41	V-disp19	(S + A - P) >> 2
250  * R_SPARC_GLOB_JMP	    42	V-xword64	S + A
251  * R_SPARC_7		    43	V-imm7		S + A
252  * R_SPARC_5		    44	V-imm5		S + A
253  * R_SPARC_6		    45	V-imm6		S + A
254  * R_SPARC_DISP64	    46	V-xword64	S + A - P
255  * R_SPARC_PLT64	    47	V-xword64	L + A
256  * R_SPARC_HIX22	    48	V-imm22		((S + A) ^
257  *						    0xffffffffffffffff) >> 10
258  * R_SPARC_LOX10	    49	T-simm13	((S + A) & 0x3ff) | 0x1c00
259  * R_SPARC_H44		    50	V-imm22		(S + A) >> 22
260  * R_SPARC_M44		    51	T-imm10		((S + A) >> 12) & 0x3ff
261  * R_SPARC_L44		    52	T-imm13		(S + A) & 0xfff
262  * R_SPARC_REGISTER	    53	V-xword64	S + A
263  * R_SPARC_UA64		    54	V-xword64	S + A
264  * R_SPARC_UA16		    55	V-half16	S + A
265  * R_SPARC_TLS_GD_HI22	    56	T-simm22	@dtlndx(S + A) >> 10
266  * R_SPARC_TLS_GD_LO10	    57	T-simm13	@dtlndx(S + A) & 0x3ff
267  * R_SPARC_TLS_GD_ADD	    58	none		SPECIAL
268  * R_SPARC_TLS_GD_CALL	    59	V-disp30	SPECIAL
269  * R_SPARC_TLS_LDM_HI22	    60	T-simm22	@tmndx(S + A) >> 10
270  * R_SPARC_TLS_LDM_LO10	    61	T-simm13	@tmndx(S + A) & 0x3ff
271  * R_SPARC_TLS_LDM_ADD	    62	none		SPECIAL
272  * R_SPARC_TLS_LDM_CALL	    63	V-disp30	SPECIAL
273  * R_SPARC_TLS_LDO_HIX22    64	V-simm22	@dtpoff(S + A) >> 10
274  * R_SPARC_TLS_LDO_LOX10    65	T-simm13	@dtpoff(S + A) & 0x3ff
275  * R_SPARC_TLS_LDO_ADD	    66	none		SPECIAL
276  * R_SPARC_TLS_IE_HI22	    67	T-simm22	@got(@tpoff(S + A)) >> 10
277  * R_SPARC_TLS_IE_LO10	    68	T-simm13	@got(@tpoff(S + A)) & 0x3ff
278  * R_SPARC_TLS_IE_LD	    69	none		SPECIAL
279  * R_SPARC_TLS_IE_LDX	    70	none		SPECIAL
280  * R_SPARC_TLS_IE_ADD	    71	none		SPECIAL
281  * R_SPARC_TLS_LE_HIX22	    72	V-simm22	(@tpoff(S + A) ^
282  *						    0xffffffff) >> 10
283  * R_SPARC_TLS_LE_LOX10	    73	T-simm13	(@tpoff(S + A) & 0x3ff) | 0x1c00
284  * R_SPARC_TLS_DTPMOD32	    74	V-word32	@dtmod(S + A)
285  * R_SPARC_TLS_DTPMOD64	    75	V-word64	@dtmod(S + A)
286  * R_SPARC_TLS_DTPOFF32	    76	V-word32	@dtpoff(S + A)
287  * R_SPARC_TLS_DTPOFF64	    77	V-word64	@dtpoff(S + A)
288  * R_SPARC_TLS_TPOFF32	    78	V-word32	@tpoff(S + A)
289  * R_SPARC_TLS_TPOFF64	    79	V-word64	@tpoff(S + A)
290  * R_SPARC_GOTDATA_HIX22    80	V-imm22		((S + A - GOT) >> 10) ^
291  *						  ((S + A - GOT) >> 31)
292  * R_SPARC_GOTDATA_LOX10    81	T-simm13	((S + A - GOT) & 0x3ff) |
293  *						  (((S + A - GOT) >> 31) &
294  *						  0x1c00)
295  * R_SPARC_GOTDATA_OP_HIX22 82	T-imm22		(G >> 10) & (G >> 31)
296  * R_SPARC_GOTDATA_OP_LOX10 83	T-simm13	(G & 0x3ff) |
297  *						  ((G >> 31) & 0x1c00)
298  * R_SPARC_GOTDATA_OP	    84  Word32		SPECIAL
299  * R_SPARC_H34		    85	V-imm22		(S + A) >> 12
300  * R_SPARC_SIZE32	    86	V-word32	Z + A
301  * R_SPARC_SIZE64	    87	V-xword64	Z + A
302  *
303  *	This is Figure 4-20: Relocation Types from the Draft Copy of
304  * the ABI, Printed on 11/29/88.
305  *
306  * NOTE1: relocations 24->45 are newly registered relocations to support
307  *	 C++ ABI & SPARC V8+ and SPARC V9 architectures (1/9/94), and
308  *	 64-bit relocations 46-55 were added for SPARC V9.
309  *
310  * NOTE2: relocations 56->79 are added to support Thread-Local storage
311  *	  as recorded in PSARC/2001/509
312  *
313  * NOTE3: The value to be passed for relocations R_SPARC_HIX22 and
314  *	  R_SPARC_TLS_HIX22 are negative values. So the upper 10 or 40 bits
315  *	  are 1. (So when the exclusive OR is applied, the upper bits
316  *	  will be 0.)
317  *
318  * Relocation calculations:
319  *
320  * The FIELD names indicate whether the relocation type checks for overflow.
321  * A calculated relocation value may be larger than the intended field, and
322  * the relocation type may verify (V) that the value fits, or truncate (T)
323  * the result.
324  *
325  * CALCULATION uses the following notation:
326  *      A       the addend used
327  *      B       the base address of the shared object in memory
328  *      G       the offset into the global offset table
329  *      L       the procedure linkage entry
330  *      P       the place of the storage unit being relocated
331  *      S       the value of the symbol
332  *	O	secondary addend (extra offset) in v9 r_info field
333  *	Z	the size of the symbol whose index resides in the relocation
334  *		entry
335  *
336  *	@dtlndx(x): Allocate two contiguous entries in the GOT table to hold
337  *	   a Tls_index structure (for passing to __tls_get_addr()). The
338  *	   instructions referencing this entry will be bound to the first
339  *	   of the two GOT entries.
340  *
341  *	@tmndx(x): Allocate two contiguous entries in the GOT table to hold
342  *	   a Tls_index structure (for passing to __tls_get_addr()). The
343  *	   ti_offset field of the Tls_index will be set to 0 (zero) and the
344  *	   ti_module will be filled in at run-time. The call to
345  *	   __tls_get_addr() will return the starting offset of the dynamic
346  *	   TLS block.
347  *
348  *	@dtpoff(x): calculate the tlsoffset relative to the TLS block.
349  *
350  *	@tpoff(x): calculate the negative tlsoffset relative to the static
351  *	   TLS block. This value can be added to the thread-pointer to
352  *	   calculate the tls address.
353  *
354  *	@dtpmod(x): calculate the module id of the object containing symbol x.
355  *
356  * The calculations in the CALCULATION column are assumed to have been performed
357  * before calling this function except for the addition of the addresses in the
358  * instructions.
359  *
360  * Upon successful completion of do_reloc() *value will be set to the
361  * 'bit-shifted' value that will be or'ed into memory.
362  */
363 #if defined(_KERNEL)
364 #define	lml	0		/* Needed by arglist of REL_ERR_* macros */
365 int
366 do_reloc_krtld(uchar_t rtype, uchar_t *off, Xword *value, const char *sym,
367     const char *file)
368 #elif defined(DO_RELOC_LIBLD)
369 /*ARGSUSED5*/
370 int
371 do_reloc_ld(Rel_desc *rdesc, uchar_t *off, Xword *value,
372     rel_desc_sname_func_t rel_desc_sname_func,
373     const char *file, int bswap, void *lml)
374 #else
375 int
376 do_reloc_rtld(uchar_t rtype, uchar_t *off, Xword *value, const char *sym,
377     const char *file, void *lml)
378 #endif
379 {
380 #ifdef DO_RELOC_LIBLD
381 #define	sym (* rel_desc_sname_func)(rdesc)
382 	uchar_t	rtype = rdesc->rel_rtype;
383 #endif
384 	Xword	uvalue = 0;
385 	Xword	basevalue, sigbit_mask, sigfit_mask;
386 	Xword	corevalue = *value;
387 	uchar_t	bshift;
388 	int	field_size, re_flags;
389 	const	Rel_entry	*rep;
390 
391 	rep = &reloc_table[rtype];
392 	bshift = rep->re_bshift;
393 	field_size = rep->re_fsize;
394 	re_flags = rep->re_flags;
395 	sigbit_mask = S_MASK(rep->re_sigbits);
396 
397 	if ((re_flags & FLG_RE_SIGN) && sigbit_mask) {
398 		/*
399 		 * sigfit_mask takes into account that a value
400 		 * might be signed and discards the signbit for
401 		 * comparison.
402 		 */
403 		sigfit_mask = S_MASK(rep->re_sigbits - 1);
404 	} else
405 		sigfit_mask = sigbit_mask;
406 
407 	if (field_size == 0) {
408 		REL_ERR_UNIMPL(lml, file, sym, rtype);
409 		return (0);
410 	}
411 
412 	/*
413 	 * We have two ways to retrieve the base value, a general one
414 	 * that will work with data of any alignment, and another that is
415 	 * fast, but which requires the data to be aligned according to
416 	 * sparc alignment rules.
417 	 *
418 	 * For non-native linking, we always use the general path. For
419 	 * native linking, the FLG_RE_UNALIGN determines it.
420 	 */
421 #if defined(DORELOC_NATIVE)
422 	if (re_flags & FLG_RE_UNALIGN)
423 #endif
424 	{
425 		int	i;
426 		uchar_t	*dest = (uchar_t *)&basevalue;
427 
428 		basevalue = 0;
429 #if !defined(DORELOC_NATIVE)
430 		if (bswap) {
431 			int j = field_size - 1;
432 
433 			for (i = 0; i < field_size; i++, j--)
434 				dest[i] = off[j];
435 
436 		} else
437 #endif
438 		{
439 			/*
440 			 * Adjust the offset
441 			 */
442 			/* LINTED */
443 			i = (int)(sizeof (Xword) - field_size);
444 			if (i > 0)
445 				dest += i;
446 			for (i = field_size - 1; i >= 0; i--)
447 				dest[i] = off[i];
448 		}
449 	}
450 
451 	/*
452 	 * Non-native linker: We have already fetched the value above,
453 	 *	but if the relocation does not have the FLG_RE_UNALIGN
454 	 *	flag set, we still need to do the same error checking we
455 	 *	would do on a native linker.
456 	 * Native-linker: If this is an aligned relocation, we need to
457 	 *	fetch the value and also do the error checking.
458 	 *
459 	 * The FETCH macro is used to conditionalize the fetching so that
460 	 * it only happens in the native case.
461 	 */
462 #if defined(DORELOC_NATIVE)
463 #define	FETCH(_type) basevalue = (Xword)*((_type *)off);
464 #else
465 #define	FETCH(_type)
466 #endif
467 	if ((re_flags & FLG_RE_UNALIGN) == 0) {
468 		if (((field_size == 2) && ((uintptr_t)off & 0x1)) ||
469 		    ((field_size == 4) && ((uintptr_t)off & 0x3)) ||
470 		    ((field_size == 8) && ((uintptr_t)off & 0x7))) {
471 			REL_ERR_NONALIGN(lml, file, sym, rtype, (uintptr_t)off);
472 			return (0);
473 		}
474 		switch (field_size) {
475 		case 1:
476 			/* LINTED */
477 			FETCH(uchar_t);
478 			break;
479 		case 2:
480 			/* LINTED */
481 			FETCH(Half);
482 			break;
483 		case 4:
484 			/* LINTED */
485 			FETCH(Word);
486 			break;
487 		case 8:
488 			/* LINTED */
489 			FETCH(Xword);
490 			break;
491 		default:
492 			REL_ERR_UNNOBITS(lml, file, sym, rtype,
493 			    (rep->re_fsize * 8));
494 			return (0);
495 		}
496 	}
497 #undef FETCH
498 
499 	if (sigbit_mask) {
500 		/*
501 		 * The WDISP16 relocation is an unusual one in that it's bits
502 		 * are not all contiguous.  We have to selectivly pull them out.
503 		 */
504 		if (re_flags & FLG_RE_WDISP16) {
505 			uvalue = ((basevalue & 0x300000) >> 6) |
506 			    (basevalue & 0x3fff);
507 			basevalue &= ~0x303fff;
508 		} else {
509 			uvalue = sigbit_mask & basevalue;
510 			basevalue &= ~sigbit_mask;
511 		}
512 		/*
513 		 * If value is signed make sure that we signextend the uvalue.
514 		 */
515 		if (re_flags & FLG_RE_SIGN) {
516 			if (uvalue & (~sigbit_mask & sigfit_mask))
517 				uvalue |= ~sigbit_mask;
518 		}
519 	} else
520 		uvalue = basevalue;
521 
522 	if (bshift)
523 		uvalue <<= bshift;
524 
525 	uvalue += *value;
526 
527 	if (rep->re_mask &&
528 	    ((rtype == R_SPARC_HIX22) || (rtype == R_SPARC_TLS_LE_HIX22)))
529 		uvalue ^= rep->re_mask;
530 
531 	if (bshift) {
532 		/*
533 		 * This is to check that we are not attempting to
534 		 * jump to a non-4 byte aligned address.
535 		 */
536 		if ((bshift == 2) && (uvalue & 0x3)) {
537 			REL_ERR_LOSEBITS(lml, file, sym, rtype, uvalue, 2, off);
538 			return (0);
539 		}
540 
541 		if (re_flags & FLG_RE_SIGN) {
542 			uvalue = (Sxword)uvalue >> bshift;
543 		} else {
544 			uvalue >>= bshift;
545 		}
546 		corevalue >>= bshift;
547 	}
548 
549 	if ((rtype == R_SPARC_GOTDATA_HIX22) ||
550 	    (rtype == R_SPARC_GOTDATA_OP_HIX22)) {
551 		uvalue ^= ((Sxword)(*value) >> 31);
552 		corevalue ^= ((Sxword)(*value) >> 31);
553 	}
554 
555 	if (rep->re_mask &&
556 	    (rtype != R_SPARC_HIX22) && (rtype != R_SPARC_TLS_LE_HIX22) &&
557 	    (rtype != R_SPARC_GOTDATA_HIX22))
558 		uvalue &= rep->re_mask;
559 
560 	if ((rtype == R_SPARC_LOX10) || (rtype == R_SPARC_TLS_LE_LOX10)) {
561 		uvalue |= 0x1c00;
562 		corevalue |= 0x1c00;
563 	}
564 
565 	if ((rtype == R_SPARC_GOTDATA_LOX10) ||
566 	    (rtype == R_SPARC_GOTDATA_OP_LOX10)) {
567 		uvalue |= ((Sxword)(*value) >> 31) & 0x1c00;
568 		corevalue |= ((Sxword)(*value) >> 31) & 0x1c00;
569 	}
570 
571 
572 	if ((re_flags & FLG_RE_VERIFY) && sigbit_mask) {
573 		if (((re_flags & FLG_RE_SIGN) &&
574 		    (S_INRANGE((Sxword)uvalue, rep->re_sigbits - 1) == 0)) ||
575 		    (!(re_flags & FLG_RE_SIGN) &&
576 		    ((sigbit_mask & uvalue) != uvalue))) {
577 			REL_ERR_NOFIT(lml, file, sym, rtype, uvalue);
578 			return (0);
579 		}
580 	}
581 
582 	if (sigbit_mask) {
583 		/*
584 		 * Again the R_SPARC_WDISP16 relocation takes special
585 		 * processing because of its non-continguous bits.
586 		 */
587 		if (re_flags & FLG_RE_WDISP16)
588 			uvalue = ((uvalue & 0xc000) << 6) |
589 			    (uvalue & 0x3fff);
590 		else
591 			uvalue &= sigbit_mask;
592 		/*
593 		 * Combine value back with original word
594 		 */
595 		uvalue |= basevalue;
596 	}
597 	*value = corevalue;
598 
599 	/*
600 	 * Now, we store uvalue back at the location given by off.
601 	 * This is similar to the fetch case above:
602 	 *	- We have general (unaligned) and fast (aligned) cases
603 	 *	- Cross linkers need to use the unaligned case even
604 	 *		when the relocation does not specify FLG_RE_UNALIGN.
605 	 *	- A cross linker that processes a relocation that does not
606 	 *		have FLG_RE_UNALIGN set has to do the same error
607 	 *		checking that a native linker would do, while avoiding
608 	 *		the aligned store (accomplished with the STORE macro).
609 	 */
610 #if defined(DORELOC_NATIVE)
611 	if (re_flags & FLG_RE_UNALIGN)
612 #endif
613 	{
614 		int	i;
615 		uchar_t	*src = (uchar_t *)&uvalue;
616 
617 #if !defined(DORELOC_NATIVE)
618 		if (bswap) {
619 			int j = field_size - 1;
620 
621 			for (i = 0; i < field_size; i++, j--)
622 				off[i] = src[j];
623 
624 		} else
625 #endif
626 		{
627 			/*
628 			 * Adjust the offset.
629 			 */
630 			/* LINTED */
631 			i = (int)(sizeof (Xword) - field_size);
632 			if (i > 0)
633 				src += i;
634 			for (i = field_size - 1; i >= 0; i--)
635 				off[i] = src[i];
636 		}
637 	}
638 
639 #if defined(DORELOC_NATIVE)
640 #define	STORE(_type) *((_type *)off) = (_type)uvalue
641 #else
642 #define	STORE(_type)
643 #endif
644 	if ((re_flags & FLG_RE_UNALIGN) == 0) {
645 		switch (rep->re_fsize) {
646 		case 1:
647 			/* LINTED */
648 			STORE(uchar_t);
649 			break;
650 		case 2:
651 			/* LINTED */
652 			STORE(Half);
653 			break;
654 		case 4:
655 			/* LINTED */
656 			STORE(Word);
657 			break;
658 		case 8:
659 			/* LINTED */
660 			STORE(Xword);
661 			break;
662 		default:
663 			/*
664 			 * To keep chkmsg() happy: MSG_INTL(MSG_REL_UNSUPSZ)
665 			 */
666 			REL_ERR_UNSUPSZ(lml, file, sym, rtype, rep->re_fsize);
667 			return (0);
668 		}
669 	}
670 #undef STORE
671 
672 	return (1);
673 
674 #ifdef DO_RELOC_LIBLD
675 #undef sym
676 #endif
677 }
678