xref: /titanic_41/usr/src/lib/libc/i386/crt/_rtboot.s (revision 8fd04b8338ed5093ec2d1e668fa620b7de44c177)
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 2010 Sun Microsystems, Inc.  All rights reserved.
24 * Use is subject to license terms.
25 */
26
27	.file	"_rtboot.s"
28
29/ bootstrap routine for run-time linker
30/ we get control from exec which has loaded our text and
31/ data into the process' address space and created the process
32/ stack
33/
34/ on entry, the process stack looks like this:
35/
36/			# <- %esp
37/_______________________#  high addresses
38/	strings		#
39/_______________________#
40/	0 word		#
41/_______________________#
42/	Auxiliary	#
43/	entries		#
44/	...		#
45/	(size varies)	#
46/_______________________#
47/	0 word		#
48/_______________________#
49/	Environment	#
50/	pointers	#
51/	...		#
52/	(one word each)	#
53/_______________________#
54/	0 word		#
55/_______________________#
56/	Argument	# low addresses
57/	pointers	#
58/	Argc words	#
59/_______________________#
60/	argc		#
61/_______________________# <- %ebp
62
63#include <SYS.h>
64
65	.set	EB_NULL,0
66	.set	EB_DYNAMIC,1
67	.set	EB_LDSO_BASE,2
68	.set	EB_ARGV,3
69	.set	EB_ENVP,4
70	.set	EB_AUXV,5
71	.set	EB_DEVZERO,6
72	.set	EB_PAGESIZE,7
73	.set	EB_MAX,8
74	.set	EB_MAX_SIZE32,64
75
76	.text
77	.globl	__rtboot
78	.globl	__rtld
79	.type	__rtboot,@function
80	.align	4
81__rtboot:
82	movl	%esp,%ebp
83	subl	$EB_MAX_SIZE32,%esp	/ make room for a max sized boot vector
84	movl	%esp,%esi		/ use esi as a pointer to &eb[0]
85	movl	$EB_ARGV,0(%esi)	/ set up tag for argv
86	leal	4(%ebp),%eax		/ get address of argv
87	movl	%eax,4(%esi)		/ put after tag
88	movl	$EB_ENVP,8(%esi)	/ set up tag for envp
89	movl	(%ebp),%eax		/ get # of args
90	addl	$2,%eax			/ one for the zero & one for argc
91	leal	(%ebp,%eax,4),%edi	/ now points past args & @ envp
92	movl	%edi,12(%esi)		/ set envp
93	addl	$-4,%edi		/ start loop at &env[-1]
94.L00:	addl	$4,%edi			/ next
95	cmpl	$0,(%edi)		/ search for 0 at end of env
96	jne	.L00
97	addl	$4,%edi			/ advance past 0
98	movl	$EB_AUXV,16(%esi)	/ set up tag for auxv
99	movl	%edi,20(%esi)		/ point to auxv
100	movl	$EB_NULL,24(%esi)	/ set up NULL tag
101	call	.L01		/ only way to get IP into a register
102.L01:	popl	%ebx		/ pop the IP we just "pushed"
103	leal	s.EMPTY - .L01(%ebx),%eax
104	pushl	%eax
105	leal	s.ZERO - .L01(%ebx),%eax
106	pushl	%eax
107	leal	s.LDSO - .L01(%ebx),%eax
108	pushl	%eax
109	movl	%esp,%edi	/ save pointer to strings
110	leal	f.MUNMAP - .L01(%ebx),%eax
111	pushl	%eax
112	leal	f.CLOSE - .L01(%ebx),%eax
113	pushl	%eax
114	leal	f.SYSCONFIG - .L01(%ebx),%eax
115	pushl	%eax
116	leal	f.FSTATAT - .L01(%ebx),%eax
117	pushl	%eax
118	leal	f.MMAP - .L01(%ebx),%eax
119	pushl	%eax
120	leal	f.OPENAT - .L01(%ebx),%eax
121	pushl	%eax
122	leal	f.PANIC - .L01(%ebx),%eax
123	pushl	%eax
124	movl	%esp,%ecx	/ save pointer to functions
125
126	pushl	%ecx		/ address of functions
127	pushl	%edi		/ address of strings
128	pushl	%esi		/ &eb[0]
129	call	__rtld		/ __rtld(&eb[0], strings, funcs)
130	movl	%esi,%esp	/ restore the stack (but leaving boot vector)
131	jmp	*%eax 		/ transfer control to ld.so.1
132	.size	__rtboot,.-__rtboot
133
134	.align	4
135s.LDSO:		.string	"/usr/lib/ld.so.1"
136s.ZERO:		.string	"/dev/zero"
137s.EMPTY:	.string	"(null)"
138s.ERROR:	.string	": no (or bad) /usr/lib/ld.so.1\n"
139l.ERROR:
140
141	.align	4
142f.PANIC:
143	movl	%esp,%ebp
144/ Add using of argument string
145	pushl	$l.ERROR - s.ERROR
146	call	.L02
147.L02:	popl	%ebx
148	leal	s.ERROR - .L02(%ebx),%eax
149	pushl	%eax
150	pushl	$2
151	call	f.WRITE
152	jmp	f.EXIT
153/ Not reached
154
155f.OPENAT:
156	movl	$SYS_openat,%eax
157	jmp	__syscall
158f.MMAP:
159	movl	$SYS_mmap,%eax
160	jmp	__syscall
161f.MUNMAP:
162	movl	$SYS_munmap,%eax
163	jmp	__syscall
164f.READ:
165	movl	$SYS_read,%eax
166	jmp	__syscall
167f.WRITE:
168	movl	$SYS_write,%eax
169	jmp	__syscall
170f.LSEEK:
171	movl	$SYS_lseek,%eax
172	jmp	__syscall
173f.CLOSE:
174	movl	$SYS_close,%eax
175	jmp	__syscall
176f.FSTATAT:
177	movl	$SYS_fstatat,%eax
178	jmp	__syscall
179f.SYSCONFIG:
180	movl	$SYS_sysconfig,%eax
181	jmp	__syscall
182f.EXIT:
183	movl	$SYS_exit,%eax
184/	jmp	__syscall
185__syscall:
186	int	$T_SYSCALLINT
187	jc	__err_exit
188	ret
189__err_exit:
190	movl	$-1,%eax
191	ret
192