1 /*-
2 * Copyright (c) 2015-2016 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 #include <sys/param.h>
28 #include <sys/imgact.h>
29 #include <sys/kernel.h>
30 #include <sys/proc.h>
31 #include <sys/sysent.h>
32
33 #include <vm/vm.h>
34 #include <vm/pmap.h>
35
36 #include <machine/frame.h>
37 #include <machine/pcb.h>
38 #include <machine/vmparam.h>
39
40 #include <compat/cloudabi/cloudabi_util.h>
41
42 #include <compat/cloudabi32/cloudabi32_syscall.h>
43 #include <compat/cloudabi32/cloudabi32_util.h>
44
45 extern const char *cloudabi32_syscallnames[];
46 extern struct sysent cloudabi32_sysent[];
47
48 static void
cloudabi32_proc_setregs(struct thread * td,struct image_params * imgp,uintptr_t stack)49 cloudabi32_proc_setregs(struct thread *td, struct image_params *imgp,
50 uintptr_t stack)
51 {
52 struct trapframe *regs;
53
54 exec_setregs(td, imgp, stack);
55
56 /*
57 * The stack now contains a pointer to the TCB and the auxiliary
58 * vector. Let r0 point to the auxiliary vector, and set
59 * tpidrurw to the TCB.
60 */
61 regs = td->td_frame;
62 regs->tf_r0 =
63 stack + roundup(sizeof(cloudabi32_tcb_t), sizeof(register_t));
64 (void)cpu_set_user_tls(td, TO_PTR(stack));
65 }
66
67 static int
cloudabi32_fetch_syscall_args(struct thread * td)68 cloudabi32_fetch_syscall_args(struct thread *td)
69 {
70 struct trapframe *frame;
71 struct syscall_args *sa;
72 int error;
73
74 frame = td->td_frame;
75 sa = &td->td_sa;
76
77 /* Obtain system call number. */
78 sa->code = frame->tf_r12;
79 if (sa->code >= CLOUDABI32_SYS_MAXSYSCALL)
80 return (ENOSYS);
81 sa->callp = &cloudabi32_sysent[sa->code];
82
83 /* Fetch system call arguments from registers and the stack. */
84 sa->args[0] = frame->tf_r0;
85 sa->args[1] = frame->tf_r1;
86 sa->args[2] = frame->tf_r2;
87 sa->args[3] = frame->tf_r3;
88 if (sa->callp->sy_narg > 4) {
89 error = copyin((void *)td->td_frame->tf_usr_sp, &sa->args[4],
90 (sa->callp->sy_narg - 4) * sizeof(register_t));
91 if (error != 0)
92 return (error);
93 }
94
95 /* Default system call return values. */
96 td->td_retval[0] = 0;
97 td->td_retval[1] = frame->tf_r1;
98 return (0);
99 }
100
101 static void
cloudabi32_set_syscall_retval(struct thread * td,int error)102 cloudabi32_set_syscall_retval(struct thread *td, int error)
103 {
104 struct trapframe *frame = td->td_frame;
105
106 switch (error) {
107 case 0:
108 /* System call succeeded. */
109 frame->tf_r0 = td->td_retval[0];
110 frame->tf_r1 = td->td_retval[1];
111 frame->tf_spsr &= ~PSR_C;
112 break;
113 case ERESTART:
114 /* Restart system call. */
115 frame->tf_pc -= 4;
116 break;
117 case EJUSTRETURN:
118 break;
119 default:
120 /* System call returned an error. */
121 frame->tf_r0 = cloudabi_convert_errno(error);
122 frame->tf_spsr |= PSR_C;
123 break;
124 }
125 }
126
127 static void
cloudabi32_schedtail(struct thread * td)128 cloudabi32_schedtail(struct thread *td)
129 {
130 struct trapframe *frame = td->td_frame;
131
132 /*
133 * Initial register values for processes returning from fork.
134 * Make sure that we only set these values when forking, not
135 * when creating a new thread.
136 */
137 if ((td->td_pflags & TDP_FORKING) != 0) {
138 frame->tf_r0 = CLOUDABI_PROCESS_CHILD;
139 frame->tf_r1 = td->td_tid;
140 }
141 }
142
143 int
cloudabi32_thread_setregs(struct thread * td,const cloudabi32_threadattr_t * attr,uint32_t tcb)144 cloudabi32_thread_setregs(struct thread *td,
145 const cloudabi32_threadattr_t *attr, uint32_t tcb)
146 {
147 struct trapframe *frame;
148 stack_t stack;
149
150 /* Perform standard register initialization. */
151 stack.ss_sp = TO_PTR(attr->stack);
152 stack.ss_size = attr->stack_len;
153 cpu_set_upcall(td, TO_PTR(attr->entry_point), NULL, &stack);
154
155 /*
156 * Pass in the thread ID of the new thread and the argument
157 * pointer provided by the parent thread in as arguments to the
158 * entry point.
159 */
160 frame = td->td_frame;
161 frame->tf_r0 = td->td_tid;
162 frame->tf_r1 = attr->argument;
163
164 /* Set up TLS. */
165 return (cpu_set_user_tls(td, TO_PTR(tcb)));
166 }
167
168 static struct sysentvec cloudabi32_elf_sysvec = {
169 .sv_size = CLOUDABI32_SYS_MAXSYSCALL,
170 .sv_table = cloudabi32_sysent,
171 .sv_fixup = cloudabi32_fixup,
172 .sv_name = "CloudABI ELF32",
173 .sv_coredump = elf32_coredump,
174 .sv_elf_core_osabi = ELFOSABI_FREEBSD,
175 .sv_elf_core_abi_vendor = FREEBSD_ABI_VENDOR,
176 .sv_elf_core_prepare_notes = elf32_prepare_notes,
177 .sv_minuser = VM_MIN_ADDRESS,
178 .sv_maxuser = VM_MAXUSER_ADDRESS,
179 .sv_stackprot = VM_PROT_READ | VM_PROT_WRITE,
180 .sv_copyout_strings = cloudabi32_copyout_strings,
181 .sv_setregs = cloudabi32_proc_setregs,
182 .sv_flags = SV_ABI_CLOUDABI | SV_CAPSICUM | SV_ILP32,
183 .sv_set_syscall_retval = cloudabi32_set_syscall_retval,
184 .sv_fetch_syscall_args = cloudabi32_fetch_syscall_args,
185 .sv_syscallnames = cloudabi32_syscallnames,
186 .sv_schedtail = cloudabi32_schedtail,
187 };
188
189 INIT_SYSENTVEC(elf_sysvec, &cloudabi32_elf_sysvec);
190
191 Elf32_Brandinfo cloudabi32_brand = {
192 .brand = ELFOSABI_CLOUDABI,
193 .machine = EM_ARM,
194 .sysvec = &cloudabi32_elf_sysvec,
195 .flags = BI_BRAND_ONLY_STATIC,
196 };
197