freebsd-nq/sys/amd64/cloudabi32/cloudabi32_sysvec.c
Edward Tomasz Napierala 1e2521ffae Get rid of sa->narg. It serves no purpose; use sa->callp->sy_narg instead.
Reviewed by:	kib
Sponsored by:	DARPA
Differential Revision:	https://reviews.freebsd.org/D26458
2020-09-27 18:47:06 +00:00

234 lines
6.8 KiB
C

/*-
* Copyright (c) 2015-2016 Nuxi, https://nuxi.nl/
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/imgact.h>
#include <sys/kernel.h>
#include <sys/proc.h>
#include <sys/sysent.h>
#include <vm/vm.h>
#include <vm/pmap.h>
#include <machine/frame.h>
#include <machine/pcb.h>
#include <machine/vmparam.h>
#include <compat/cloudabi/cloudabi_util.h>
#include <compat/cloudabi32/cloudabi32_syscall.h>
#include <compat/cloudabi32/cloudabi32_util.h>
#include <compat/ia32/ia32_signal.h>
#include <compat/ia32/ia32_util.h>
extern const char *cloudabi32_syscallnames[];
extern struct sysent cloudabi32_sysent[];
extern unsigned long ia32_maxssiz;
static int
cloudabi32_fixup_tcb(uintptr_t *stack_base, struct image_params *imgp)
{
int error;
uint32_t args[2];
/* Place auxiliary vector and TCB on the stack. */
error = cloudabi32_fixup(stack_base, imgp);
if (error != 0)
return (error);
/*
* On i386, the TCB is referred to by %gs:0. Reuse the empty
* space normally used by the return address (args[0]) to store
* a single element array, containing a pointer to the TCB. %gs
* base will point to this.
*
* Also let the first argument of the entry point (args[1])
* refer to the auxiliary vector, which is stored right after
* the TCB.
*/
args[0] = *stack_base;
args[1] = *stack_base +
roundup(sizeof(cloudabi32_tcb_t), sizeof(register_t));
*stack_base -= roundup2(sizeof(args), sizeof(register_t));
return (copyout(args, (void *)*stack_base, sizeof(args)));
}
static void
cloudabi32_proc_setregs(struct thread *td, struct image_params *imgp,
uintptr_t stack)
{
ia32_setregs(td, imgp, stack);
(void)cpu_set_user_tls(td, TO_PTR(stack));
}
static int
cloudabi32_fetch_syscall_args(struct thread *td)
{
struct trapframe *frame;
struct syscall_args *sa;
int error;
frame = td->td_frame;
sa = &td->td_sa;
/* Obtain system call number. */
sa->code = frame->tf_rax;
if (sa->code >= CLOUDABI32_SYS_MAXSYSCALL)
return (ENOSYS);
sa->callp = &cloudabi32_sysent[sa->code];
/*
* Fetch system call arguments.
*
* The vDSO has already made sure that the arguments are
* eight-byte aligned. Pointers and size_t parameters are
* zero-extended. This makes it possible to copy in the
* arguments directly. As long as the call doesn't use 32-bit
* data structures, we can just invoke the same system call
* implementation used by 64-bit processes.
*/
error = copyin((void *)frame->tf_rcx, sa->args,
sa->callp->sy_narg * sizeof(sa->args[0]));
if (error != 0)
return (error);
/* Default system call return values. */
td->td_retval[0] = 0;
td->td_retval[1] = 0;
return (0);
}
static void
cloudabi32_set_syscall_retval(struct thread *td, int error)
{
struct trapframe *frame = td->td_frame;
switch (error) {
case 0:
/*
* System call succeeded.
*
* Simply copy out the 64-bit return values into the
* same buffer provided for system call arguments. The
* vDSO will copy them to the right spot, truncating
* pointers and size_t values to 32 bits.
*/
frame->tf_rax = copyout(td->td_retval, (void *)frame->tf_rcx,
sizeof(td->td_retval)) == 0 ? 0 : CLOUDABI_EFAULT;
break;
case ERESTART:
/* Restart system call. */
frame->tf_rip -= frame->tf_err;
frame->tf_r10 = frame->tf_rcx;
set_pcb_flags(td->td_pcb, PCB_FULL_IRET);
break;
case EJUSTRETURN:
break;
default:
/* System call returned an error. */
frame->tf_rax = cloudabi_convert_errno(error);
break;
}
}
static void
cloudabi32_schedtail(struct thread *td)
{
struct trapframe *frame = td->td_frame;
register_t retval[2];
/* Return values for processes returning from fork. */
if ((td->td_pflags & TDP_FORKING) != 0) {
retval[0] = CLOUDABI_PROCESS_CHILD;
retval[1] = td->td_tid;
copyout(retval, (void *)frame->tf_rcx, sizeof(retval));
}
}
int
cloudabi32_thread_setregs(struct thread *td,
const cloudabi32_threadattr_t *attr, uint32_t tcb)
{
stack_t stack;
uint32_t args[3];
void *frameptr;
int error;
/* Perform standard register initialization. */
stack.ss_sp = TO_PTR(attr->stack);
stack.ss_size = attr->stack_len - sizeof(args);
cpu_set_upcall(td, TO_PTR(attr->entry_point), NULL, &stack);
/*
* Copy the arguments for the thread entry point onto the stack
* (args[1] and args[2]). Similar to process startup, use the
* otherwise unused return address (args[0]) for TLS.
*/
args[0] = tcb;
args[1] = td->td_tid;
args[2] = attr->argument;
frameptr = (void *)td->td_frame->tf_rsp;
error = copyout(args, frameptr, sizeof(args));
if (error != 0)
return (error);
return (cpu_set_user_tls(td, frameptr));
}
static struct sysentvec cloudabi32_elf_sysvec = {
.sv_size = CLOUDABI32_SYS_MAXSYSCALL,
.sv_table = cloudabi32_sysent,
.sv_fixup = cloudabi32_fixup_tcb,
.sv_name = "CloudABI ELF32",
.sv_coredump = elf32_coredump,
.sv_minuser = FREEBSD32_MINUSER,
.sv_maxuser = FREEBSD32_MAXUSER,
.sv_stackprot = VM_PROT_READ | VM_PROT_WRITE,
.sv_copyout_strings = cloudabi32_copyout_strings,
.sv_setregs = cloudabi32_proc_setregs,
.sv_fixlimit = ia32_fixlimit,
.sv_maxssiz = &ia32_maxssiz,
.sv_flags = SV_ABI_CLOUDABI | SV_CAPSICUM | SV_IA32 | SV_ILP32,
.sv_set_syscall_retval = cloudabi32_set_syscall_retval,
.sv_fetch_syscall_args = cloudabi32_fetch_syscall_args,
.sv_syscallnames = cloudabi32_syscallnames,
.sv_schedtail = cloudabi32_schedtail,
};
INIT_SYSENTVEC(elf_sysvec, &cloudabi32_elf_sysvec);
Elf32_Brandinfo cloudabi32_brand = {
.brand = ELFOSABI_CLOUDABI,
.machine = EM_386,
.sysvec = &cloudabi32_elf_sysvec,
.flags = BI_BRAND_ONLY_STATIC,
};