sys/arm64/cloudabi64/cloudabi64_sysvec.c

   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("$FreeBSD$");
  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
  47 extern const char *cloudabi64_syscallnames[];
  48 extern struct sysent cloudabi64_sysent[];
  49
  50 static void
  51 cloudabi64_proc_setregs(struct thread *td, struct image_params *imgp,
  52     uintptr_t 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] =
  65             stack + roundup(sizeof(cloudabi64_tcb_t), sizeof(register_t));
  66         (void)cpu_set_user_tls(td, TO_PTR(stack));
  67 }
  68
  69 static int
  70 cloudabi64_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
  96 static void
  97 cloudabi64_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
 122 static void
 123 cloudabi64_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
 138 int
 139 cloudabi64_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, TO_PTR(tcb)));
 161 }
 162
 163 static 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_minuser             = VM_MIN_ADDRESS,
 170         .sv_maxuser             = VM_MAXUSER_ADDRESS,
 171         .sv_stackprot           = VM_PROT_READ | VM_PROT_WRITE,
 172         .sv_copyout_strings     = cloudabi64_copyout_strings,
 173         .sv_setregs             = cloudabi64_proc_setregs,
 174         .sv_flags               = SV_ABI_CLOUDABI | SV_CAPSICUM | SV_LP64,
 175         .sv_set_syscall_retval  = cloudabi64_set_syscall_retval,
 176         .sv_fetch_syscall_args  = cloudabi64_fetch_syscall_args,
 177         .sv_syscallnames        = cloudabi64_syscallnames,
 178         .sv_schedtail           = cloudabi64_schedtail,
 179 };
 180
 181 INIT_SYSENTVEC(elf_sysvec, &cloudabi64_elf_sysvec);
 182
 183 Elf64_Brandinfo cloudabi64_brand = {
 184         .brand          = ELFOSABI_CLOUDABI,
 185         .machine        = EM_AARCH64,
 186         .sysvec         = &cloudabi64_elf_sysvec,
 187         .flags          = BI_CAN_EXEC_DYN | BI_BRAND_ONLY_STATIC,
 188 };