cloudabi64_sysvec.c revision 321343 
1/*-
2 * Copyright (c) 2015 Nuxi, https://nuxi.nl/
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 *    notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 *    notice, this list of conditions and the following disclaimer in the
11 *    documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
14 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
17 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23 * SUCH DAMAGE.
24 */
25
26#include <sys/cdefs.h>
27__FBSDID("$FreeBSD: stable/11/sys/arm64/cloudabi64/cloudabi64_sysvec.c 321343 2017-07-21 18:06:57Z kib $");
28
29#include <sys/param.h>
30#include <sys/imgact.h>
31#include <sys/kernel.h>
32#include <sys/proc.h>
33#include <sys/sysent.h>
34
35#include <vm/vm.h>
36#include <vm/pmap.h>
37
38#include <machine/frame.h>
39#include <machine/pcb.h>
40#include <machine/vmparam.h>
41
42#include <compat/cloudabi/cloudabi_util.h>
43
44#include <compat/cloudabi64/cloudabi64_syscall.h>
45#include <compat/cloudabi64/cloudabi64_util.h>
46
47extern const char *cloudabi64_syscallnames[];
48extern struct sysent cloudabi64_sysent[];
49
50static void
51cloudabi64_proc_setregs(struct thread *td, struct image_params *imgp,
52    unsigned long stack)
53{
54	struct trapframe *regs;
55
56	exec_setregs(td, imgp, stack);
57
58	/*
59	 * The stack now contains a pointer to the TCB and the auxiliary
60	 * vector. Let x0 point to the auxiliary vector, and set
61	 * tpidr_el0 to the TCB.
62	 */
63	regs = td->td_frame;
64	regs->tf_x[0] = td->td_retval[0] =
65	    stack + roundup(sizeof(cloudabi64_tcb_t), sizeof(register_t));
66	(void)cpu_set_user_tls(td, (void *)stack);
67}
68
69static int
70cloudabi64_fetch_syscall_args(struct thread *td)
71{
72	struct trapframe *frame;
73	struct syscall_args *sa;
74	int i;
75
76	frame = td->td_frame;
77	sa = &td->td_sa;
78
79	/* Obtain system call number. */
80	sa->code = frame->tf_x[8];
81	if (sa->code >= CLOUDABI64_SYS_MAXSYSCALL)
82		return (ENOSYS);
83	sa->callp = &cloudabi64_sysent[sa->code];
84	sa->narg = sa->callp->sy_narg;
85
86	/* Fetch system call arguments. */
87	for (i = 0; i < MAXARGS; i++)
88		sa->args[i] = frame->tf_x[i];
89
90	/* Default system call return values. */
91	td->td_retval[0] = 0;
92	td->td_retval[1] = frame->tf_x[1];
93	return (0);
94}
95
96static void
97cloudabi64_set_syscall_retval(struct thread *td, int error)
98{
99	struct trapframe *frame = td->td_frame;
100
101	switch (error) {
102	case 0:
103		/* System call succeeded. */
104		frame->tf_x[0] = td->td_retval[0];
105		frame->tf_x[1] = td->td_retval[1];
106		frame->tf_spsr &= ~PSR_C;
107		break;
108	case ERESTART:
109		/* Restart system call. */
110		frame->tf_elr -= 4;
111		break;
112	case EJUSTRETURN:
113		break;
114	default:
115		/* System call returned an error. */
116		frame->tf_x[0] = cloudabi_convert_errno(error);
117		frame->tf_spsr |= PSR_C;
118		break;
119	}
120}
121
122static void
123cloudabi64_schedtail(struct thread *td)
124{
125	struct trapframe *frame = td->td_frame;
126
127	/*
128	 * Initial register values for processes returning from fork.
129	 * Make sure that we only set these values when forking, not
130	 * when creating a new thread.
131	 */
132	if ((td->td_pflags & TDP_FORKING) != 0) {
133		frame->tf_x[0] = CLOUDABI_PROCESS_CHILD;
134		frame->tf_x[1] = td->td_tid;
135	}
136}
137
138int
139cloudabi64_thread_setregs(struct thread *td,
140    const cloudabi64_threadattr_t *attr, uint64_t tcb)
141{
142	struct trapframe *frame;
143	stack_t stack;
144
145	/* Perform standard register initialization. */
146	stack.ss_sp = TO_PTR(attr->stack);
147	stack.ss_size = attr->stack_len;
148	cpu_set_upcall(td, TO_PTR(attr->entry_point), NULL, &stack);
149
150	/*
151	 * Pass in the thread ID of the new thread and the argument
152	 * pointer provided by the parent thread in as arguments to the
153	 * entry point.
154	 */
155	frame = td->td_frame;
156	frame->tf_x[0] = td->td_tid;
157	frame->tf_x[1] = attr->argument;
158
159	/* Set up TLS. */
160	return (cpu_set_user_tls(td, (void *)tcb));
161}
162
163static struct sysentvec cloudabi64_elf_sysvec = {
164	.sv_size		= CLOUDABI64_SYS_MAXSYSCALL,
165	.sv_table		= cloudabi64_sysent,
166	.sv_fixup		= cloudabi64_fixup,
167	.sv_name		= "CloudABI ELF64",
168	.sv_coredump		= elf64_coredump,
169	.sv_pagesize		= PAGE_SIZE,
170	.sv_minuser		= VM_MIN_ADDRESS,
171	.sv_maxuser		= VM_MAXUSER_ADDRESS,
172	.sv_stackprot		= VM_PROT_READ | VM_PROT_WRITE,
173	.sv_copyout_strings	= cloudabi64_copyout_strings,
174	.sv_setregs		= cloudabi64_proc_setregs,
175	.sv_flags		= SV_ABI_CLOUDABI | SV_CAPSICUM | SV_LP64,
176	.sv_set_syscall_retval	= cloudabi64_set_syscall_retval,
177	.sv_fetch_syscall_args	= cloudabi64_fetch_syscall_args,
178	.sv_syscallnames	= cloudabi64_syscallnames,
179	.sv_schedtail		= cloudabi64_schedtail,
180};
181
182INIT_SYSENTVEC(elf_sysvec, &cloudabi64_elf_sysvec);
183
184Elf64_Brandinfo cloudabi64_brand = {
185	.brand		= ELFOSABI_CLOUDABI,
186	.machine	= EM_AARCH64,
187	.sysvec		= &cloudabi64_elf_sysvec,
188	.flags		= BI_CAN_EXEC_DYN | BI_BRAND_ONLY_STATIC,
189};
190