gem5/sim/syscall_emul.cc
Korey Sewell 8ddd509c7c steps toward making syscalls work
arch/mips/isa/decoder.isa:
arch/mips/isa_traits.hh:
sim/syscall_emul.cc:
    make syscall instruction functional
arch/mips/linux_process.cc:
    add all MIPS/Linux syscalls to descriptor list

--HG--
extra : convert_revision : 5455a345e76be921e9f63b248aef874b6358e465
2006-03-18 10:51:28 -05:00

454 lines
12 KiB
C++

/*
* Copyright (c) 2003-2005 The Regents of The University of Michigan
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met: redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer;
* 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;
* neither the name of the copyright holders nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 COPYRIGHT
* OWNER 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 <fcntl.h>
#include <unistd.h>
#include <string>
#include <iostream>
#include "sim/syscall_emul.hh"
#include "base/chunk_generator.hh"
#include "base/trace.hh"
#include "cpu/exec_context.hh"
#include "cpu/base.hh"
#include "mem/page_table.hh"
#include "sim/process.hh"
#include "sim/sim_events.hh"
using namespace std;
using namespace TheISA;
void
SyscallDesc::doSyscall(int callnum, Process *process, ExecContext *xc)
{
DPRINTFR(SyscallVerbose, "%s: syscall %s called\n",
xc->getCpuPtr()->name(), name);
SyscallReturn retval = (*funcPtr)(this, callnum, process, xc);
DPRINTFR(SyscallVerbose, "%s: syscall %s returns %d\n",
xc->getCpuPtr()->name(), name, retval.value());
if (!(flags & SyscallDesc::SuppressReturnValue))
xc->setSyscallReturn(retval);
}
SyscallReturn
unimplementedFunc(SyscallDesc *desc, int callnum, Process *process,
ExecContext *xc)
{
//warn("ignoring syscall %s(%d, %d, ...)", desc->name,
// xc->getSyscallArg(0), xc->getSyscallArg(1));
fatal("syscall %s (#%d) unimplemented.", desc->name, callnum);
return 1;
}
SyscallReturn
ignoreFunc(SyscallDesc *desc, int callnum, Process *process,
ExecContext *xc)
{
warn("ignoring syscall %s(%d, %d, ...)", desc->name,
xc->getSyscallArg(0), xc->getSyscallArg(1));
return 0;
}
SyscallReturn
exitFunc(SyscallDesc *desc, int callnum, Process *process,
ExecContext *xc)
{
new SimExitEvent("target called exit()", xc->getSyscallArg(0) & 0xff);
return 1;
}
SyscallReturn
getpagesizeFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc)
{
return (int)VMPageSize;
}
SyscallReturn
obreakFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc)
{
Addr junk;
// change brk addr to first arg
Addr new_brk = xc->getSyscallArg(0);
if (new_brk != 0) {
for (ChunkGenerator gen(p->brk_point, new_brk - p->brk_point,
VMPageSize); !gen.done(); gen.next()) {
if (!p->pTable->translate(gen.addr(), junk))
p->pTable->allocate(roundDown(gen.addr(), VMPageSize),
VMPageSize);
}
p->brk_point = new_brk;
}
DPRINTF(SyscallVerbose, "Break Point changed to: %#X\n", p->brk_point);
return p->brk_point;
}
SyscallReturn
closeFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc)
{
int target_fd = xc->getSyscallArg(0);
int status = close(p->sim_fd(target_fd));
if (status >= 0)
p->free_fd(target_fd);
return status;
}
SyscallReturn
readFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc)
{
int fd = p->sim_fd(xc->getSyscallArg(0));
int nbytes = xc->getSyscallArg(2);
BufferArg bufArg(xc->getSyscallArg(1), nbytes);
int bytes_read = read(fd, bufArg.bufferPtr(), nbytes);
if (bytes_read != -1)
bufArg.copyOut(xc->getMemPort());
return bytes_read;
}
SyscallReturn
writeFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc)
{
int fd = p->sim_fd(xc->getSyscallArg(0));
int nbytes = xc->getSyscallArg(2);
BufferArg bufArg(xc->getSyscallArg(1), nbytes);
bufArg.copyIn(xc->getMemPort());
int bytes_written = write(fd, bufArg.bufferPtr(), nbytes);
fsync(fd);
return bytes_written;
}
SyscallReturn
lseekFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc)
{
int fd = p->sim_fd(xc->getSyscallArg(0));
uint64_t offs = xc->getSyscallArg(1);
int whence = xc->getSyscallArg(2);
off_t result = lseek(fd, offs, whence);
return (result == (off_t)-1) ? -errno : result;
}
SyscallReturn
munmapFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc)
{
// given that we don't really implement mmap, munmap is really easy
return 0;
}
const char *hostname = "m5.eecs.umich.edu";
SyscallReturn
gethostnameFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc)
{
int name_len = xc->getSyscallArg(1);
BufferArg name(xc->getSyscallArg(0), name_len);
strncpy((char *)name.bufferPtr(), hostname, name_len);
name.copyOut(xc->getMemPort());
return 0;
}
SyscallReturn
unlinkFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc)
{
string path;
if (!xc->getMemPort()->tryReadString(path, xc->getSyscallArg(0)))
return (TheISA::IntReg)-EFAULT;
int result = unlink(path.c_str());
return (result == -1) ? -errno : result;
}
SyscallReturn
renameFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc)
{
string old_name;
if (!xc->getMemPort()->tryReadString(old_name, xc->getSyscallArg(0)))
return -EFAULT;
string new_name;
if (!xc->getMemPort()->tryReadString(new_name, xc->getSyscallArg(1)))
return -EFAULT;
int64_t result = rename(old_name.c_str(), new_name.c_str());
return (result == -1) ? -errno : result;
}
SyscallReturn
truncateFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc)
{
string path;
if (!xc->getMemPort()->tryReadString(path, xc->getSyscallArg(0)))
return -EFAULT;
off_t length = xc->getSyscallArg(1);
int result = truncate(path.c_str(), length);
return (result == -1) ? -errno : result;
}
SyscallReturn
ftruncateFunc(SyscallDesc *desc, int num, Process *process, ExecContext *xc)
{
int fd = process->sim_fd(xc->getSyscallArg(0));
if (fd < 0)
return -EBADF;
off_t length = xc->getSyscallArg(1);
int result = ftruncate(fd, length);
return (result == -1) ? -errno : result;
}
SyscallReturn
chownFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc)
{
string path;
if (!xc->getMemPort()->tryReadString(path, xc->getSyscallArg(0)))
return -EFAULT;
/* XXX endianess */
uint32_t owner = xc->getSyscallArg(1);
uid_t hostOwner = owner;
uint32_t group = xc->getSyscallArg(2);
gid_t hostGroup = group;
int result = chown(path.c_str(), hostOwner, hostGroup);
return (result == -1) ? -errno : result;
}
SyscallReturn
fchownFunc(SyscallDesc *desc, int num, Process *process, ExecContext *xc)
{
int fd = process->sim_fd(xc->getSyscallArg(0));
if (fd < 0)
return -EBADF;
/* XXX endianess */
uint32_t owner = xc->getSyscallArg(1);
uid_t hostOwner = owner;
uint32_t group = xc->getSyscallArg(2);
gid_t hostGroup = group;
int result = fchown(fd, hostOwner, hostGroup);
return (result == -1) ? -errno : result;
}
SyscallReturn
fcntlFunc(SyscallDesc *desc, int num, Process *process,
ExecContext *xc)
{
int fd = xc->getSyscallArg(0);
if (fd < 0 || process->sim_fd(fd) < 0)
return -EBADF;
int cmd = xc->getSyscallArg(1);
switch (cmd) {
case 0: // F_DUPFD
// if we really wanted to support this, we'd need to do it
// in the target fd space.
warn("fcntl(%d, F_DUPFD) not supported, error returned\n", fd);
return -EMFILE;
case 1: // F_GETFD (get close-on-exec flag)
case 2: // F_SETFD (set close-on-exec flag)
return 0;
case 3: // F_GETFL (get file flags)
case 4: // F_SETFL (set file flags)
// not sure if this is totally valid, but we'll pass it through
// to the underlying OS
warn("fcntl(%d, %d) passed through to host\n", fd, cmd);
return fcntl(process->sim_fd(fd), cmd);
// return 0;
case 7: // F_GETLK (get lock)
case 8: // F_SETLK (set lock)
case 9: // F_SETLKW (set lock and wait)
// don't mess with file locking... just act like it's OK
warn("File lock call (fcntl(%d, %d)) ignored.\n", fd, cmd);
return 0;
default:
warn("Unknown fcntl command %d\n", cmd);
return 0;
}
}
SyscallReturn
pipePseudoFunc(SyscallDesc *desc, int callnum, Process *process,
ExecContext *xc)
{
int fds[2], sim_fds[2];
int pipe_retval = pipe(fds);
if (pipe_retval < 0) {
// error
return pipe_retval;
}
sim_fds[0] = process->alloc_fd(fds[0]);
sim_fds[1] = process->alloc_fd(fds[1]);
// Alpha Linux convention for pipe() is that fd[0] is returned as
// the return value of the function, and fd[1] is returned in r20.
xc->setIntReg(SyscallPseudoReturnReg, sim_fds[1]);
return sim_fds[0];
}
SyscallReturn
getpidPseudoFunc(SyscallDesc *desc, int callnum, Process *process,
ExecContext *xc)
{
// Make up a PID. There's no interprocess communication in
// fake_syscall mode, so there's no way for a process to know it's
// not getting a unique value.
xc->setIntReg(SyscallPseudoReturnReg, 99);
return 100;
}
SyscallReturn
getuidPseudoFunc(SyscallDesc *desc, int callnum, Process *process,
ExecContext *xc)
{
// Make up a UID and EUID... it shouldn't matter, and we want the
// simulation to be deterministic.
// EUID goes in r20.
xc->setIntReg(SyscallPseudoReturnReg, 100); //EUID
return 100; // UID
}
SyscallReturn
getgidPseudoFunc(SyscallDesc *desc, int callnum, Process *process,
ExecContext *xc)
{
// Get current group ID. EGID goes in r20.
xc->setIntReg(SyscallPseudoReturnReg, 100); //EGID
return 100;
}
SyscallReturn
setuidFunc(SyscallDesc *desc, int callnum, Process *process,
ExecContext *xc)
{
// can't fathom why a benchmark would call this.
warn("Ignoring call to setuid(%d)\n", xc->getSyscallArg(0));
return 0;
}
SyscallReturn
getpidFunc(SyscallDesc *desc, int callnum, Process *process,
ExecContext *xc)
{
// Make up a PID. There's no interprocess communication in
// fake_syscall mode, so there's no way for a process to know it's
// not getting a unique value.
xc->setIntReg(SyscallPseudoReturnReg, 99); //PID
return 100;
}
SyscallReturn
getppidFunc(SyscallDesc *desc, int callnum, Process *process,
ExecContext *xc)
{
return 99;
}
SyscallReturn
getuidFunc(SyscallDesc *desc, int callnum, Process *process,
ExecContext *xc)
{
return 100; // UID
}
SyscallReturn
geteuidFunc(SyscallDesc *desc, int callnum, Process *process,
ExecContext *xc)
{
return 100; // UID
}
SyscallReturn
getgidFunc(SyscallDesc *desc, int callnum, Process *process,
ExecContext *xc)
{
return 100;
}
SyscallReturn
getegidFunc(SyscallDesc *desc, int callnum, Process *process,
ExecContext *xc)
{
return 100;
}