/*
* Copyright (C) 2005 MIPS Technologies, Inc. All rights reserved.
*
* This program is free software; you can distribute it and/or modify it
* under the terms of the GNU General Public License (Version 2) as
* published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
*
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/unistd.h>
#include <linux/file.h>
#include <linux/fs.h>
#include <linux/syscalls.h>
#include <linux/workqueue.h>
#include <linux/errno.h>
#include <linux/list.h>
#include <asm/vpe.h>
#include <asm/rtlx.h>
#include <asm/kspd.h>
static struct workqueue_struct *workqueue = NULL;
static struct work_struct work;
extern unsigned long cpu_khz;
struct mtsp_syscall {
int cmd;
unsigned char abi;
unsigned char size;
};
struct mtsp_syscall_ret {
int retval;
int errno;
};
struct mtsp_syscall_generic {
int arg0;
int arg1;
int arg2;
int arg3;
int arg4;
int arg5;
int arg6;
};
static struct list_head kspd_notifylist;
static int sp_stopping = 0;
/* these should match with those in the SDE kit */
#define MTSP_SYSCALL_BASE 0
#define MTSP_SYSCALL_EXIT (MTSP_SYSCALL_BASE + 0)
#define MTSP_SYSCALL_OPEN (MTSP_SYSCALL_BASE + 1)
#define MTSP_SYSCALL_READ (MTSP_SYSCALL_BASE + 2)
#define MTSP_SYSCALL_WRITE (MTSP_SYSCALL_BASE + 3)
#define MTSP_SYSCALL_CLOSE (MTSP_SYSCALL_BASE + 4)
#define MTSP_SYSCALL_LSEEK32 (MTSP_SYSCALL_BASE + 5)
#define MTSP_SYSCALL_ISATTY (MTSP_SYSCALL_BASE + 6)
#define MTSP_SYSCALL_GETTIME (MTSP_SYSCALL_BASE + 7)
#define MTSP_SYSCALL_PIPEFREQ (MTSP_SYSCALL_BASE + 8)
#define MTSP_SYSCALL_GETTOD (MTSP_SYSCALL_BASE + 9)
#define MTSP_O_RDONLY 0x0000
#define MTSP_O_WRONLY 0x0001
#define MTSP_O_RDWR 0x0002
#define MTSP_O_NONBLOCK 0x0004
#define MTSP_O_APPEND 0x0008
#define MTSP_O_SHLOCK 0x0010
#define MTSP_O_EXLOCK 0x0020
#define MTSP_O_ASYNC 0x0040
#define MTSP_O_FSYNC O_SYNC
#define MTSP_O_NOFOLLOW 0x0100
#define MTSP_O_SYNC 0x0080
#define MTSP_O_CREAT 0x0200
#define MTSP_O_TRUNC 0x0400
#define MTSP_O_EXCL 0x0800
#define MTSP_O_BINARY 0x8000
#define SP_VPE 1
struct apsp_table {
int sp;
int ap;
};
/* we might want to do the mode flags too */
struct apsp_table open_flags_table[] = {
{ MTSP_O_RDWR, O_RDWR },
{ MTSP_O_WRONLY, O_WRONLY },
{ MTSP_O_CREAT, O_CREAT },
{ MTSP_O_TRUNC, O_TRUNC },
{ MTSP_O_NONBLOCK, O_NONBLOCK },
{ MTSP_O_APPEND, O_APPEND },
{ MTSP_O_NOFOLLOW, O_NOFOLLOW }
};
struct apsp_table syscall_command_table[] = {
{ MTSP_SYSCALL_OPEN, __NR_open },
{ MTSP_SYSCALL_CLOSE, __NR_close },
{ MTSP_SYSCALL_READ, __NR_read },
{ MTSP_SYSCALL_WRITE, __NR_write },
{ MTSP_SYSCALL_LSEEK32, __NR_lseek }
};
static int sp_syscall(int num, int arg0, int arg1, int arg2, int arg3)
{
register long int _num __asm__ ("$2") = num;
register long int _arg0 __asm__ ("$4") = arg0;
register long int _arg1 __asm__ ("$5") = arg1;
register long int _arg2 __asm__ ("$6") = arg2;
register long int _arg3 __asm__ ("$7") = arg3;
mm_segment_t old_fs;
old_fs = get_fs();
set_fs(KERNEL_DS);
__asm__ __volatile__ (
" syscall \n"
: "=r" (_num), "=r" (_arg3)
: "r" (_num), "r" (_arg0), "r" (_arg1), "r" (_arg2), "r" (_arg3));
set_fs(old_fs);
/* $a3 is error flag */
if (_arg3)
return -_num;
return _num;
}
static int translate_syscall_command(int cmd)
{
int i;
int ret = -1;
for (i = 0; i < ARRAY_SIZE(syscall_command_table); i++) {
if ((cmd == syscall_command_table[i].sp))
return syscall_command_table[i].ap;
}
return ret;
}
static unsigned int translate_open_flags(int flags)
{
int i;
unsigned int ret = 0;
for (i = 0; i < (sizeof(open_flags_table) / sizeof(struct apsp_table));
i++) {
if( (flags & open_flags_table[i].sp) ) {
ret |= open_flags_table[i].ap;
}
}
return ret;
}
static void sp_setfsuidgid( uid_t uid, gid_t gid)
{
current->fsuid = uid;
current->fsgid = gid;
key_fsuid_changed(current);
key_fsgid_changed(current);
}
/*
* Expects a request to be on the sysio channel. Reads it. Decides whether
* its a linux syscall and runs it, or whatever. Puts the return code back
* into the request and sends the whole thing back.
*/
void sp_work_handle_request(void)
{
struct mtsp_syscall sc;
struct mtsp_syscall_generic generic;
struct mtsp_syscall_ret ret;
struct kspd_notifications *n;
struct timeval tv;
struct timezone tz;
int cmd;
char *vcwd;
mm_segment_t old_fs;
int size;
ret.retval = -1;
if (!rtlx_read(RTLX_CHANNEL_SYSIO, &sc, sizeof(struct mtsp_syscall), 0)) {
printk(KERN_ERR "Expected request but nothing to read\n");
return;
}
size = sc.size;
if (size) {
if (!rtlx_read(RTLX_CHANNEL_SYSIO, &generic, size, 0)) {
printk(KERN_ERR "Expected request but nothing to read\n");
return;
}
}
/* Run the syscall at the priviledge of the user who loaded the
SP program */
if (vpe_getuid(SP_VPE))
sp_setfsuidgid( vpe_getuid(SP_VPE), vpe_getgid(SP_VPE));
switch (sc.cmd) {
/* needs the flags argument translating from SDE kit to
linux */
case MTSP_SYSCALL_PIPEFREQ:
ret.retval = cpu_khz * 1000;
ret.errno = 0;
break;
case MTSP_SYSCALL_GETTOD:
memset(&tz, 0, sizeof(tz));
if ((ret.retval = sp_syscall(__NR_gettimeofday, (int)&tv,
(int)&tz, 0,0)) == 0)
ret.retval = tv.tv_sec;
ret.errno = errno;
break;
case MTSP_SYSCALL_EXIT:
list_for_each_entry(n, &kspd_notifylist, list)
n->kspd_sp_exit(SP_VPE);
sp_stopping = 1;
printk(KERN_DEBUG "KSPD got exit syscall from SP exitcode %d\n",
generic.arg0);
break;
case MTSP_SYSCALL_OPEN:
generic.arg1 = translate_open_flags(generic.arg1);
vcwd = vpe_getcwd(SP_VPE);
/* change to the cwd of the process that loaded the SP program */
old_fs = get_fs();
set_fs(KERNEL_DS);
sys_chdir(vcwd);
set_fs(old_fs);
sc.cmd = __NR_open;
/* fall through */
default:
if ((sc.cmd >= __NR_Linux) &&
(sc.cmd <= (__NR_Linux + __NR_Linux_syscalls)) )
cmd = sc.cmd;
else
cmd = translate_syscall_command(sc.cmd);
if (cmd >= 0) {
ret.retval = sp_syscall(cmd, generic.arg0, generic.arg1,
generic.arg2, generic.arg3);
ret.errno = errno;
} else
printk(KERN_WARNING
"KSPD: Unknown SP syscall number %d\n", sc.cmd);
break;
} /* switch */
if (vpe_getuid(SP_VPE))
sp_setfsuidgid( 0, 0);
if ((rtlx_write(RTLX_CHANNEL_SYSIO, &ret, sizeof(struct mtsp_syscall_ret), 0))
< sizeof(struct mtsp_syscall_ret))
printk("KSPD: sp_work_handle_request failed to send to SP\n");
}
static void sp_cleanup(void)
{
struct files_struct *files = current->files;
int i, j;
struct fdtable *fdt;
j = 0;
/*
* It is safe to dereference the fd table without RCU or
* ->file_lock
*/
fdt = files_fdtable(files);
for (;;) {
unsigned long set;
i = j * __NFDBITS;
if (i >= fdt->max_fds)
break;
set = fdt->open_fds->fds_bits[j++];
while (set) {
if (set & 1) {
struct file * file = xchg(&fdt->fd[i], NULL);
if (file)
filp_close(file, files);
}
i++;
set >>= 1;
}
}
}
static int channel_open = 0;
/* the work handler */
static void sp_work(struct work_struct *unused)
{
if (!channel_open) {
if( rtlx_open(RTLX_CHANNEL_SYSIO, 1) != 0) {
printk("KSPD: unable to open sp channel\n");
sp_stopping = 1;
} else {
channel_open++;
printk(KERN_DEBUG "KSPD: SP channel opened\n");
}
} else {
/* wait for some data, allow it to sleep */
rtlx_read_poll(RTLX_CHANNEL_SYSIO, 1);
/* Check we haven't been woken because we are stopping */
if (!sp_stopping)
sp_work_handle_request();
}
if (!sp_stopping)
queue_work(workqueue, &work);
else
sp_cleanup();
}
static void startwork(int vpe)
{
sp_stopping = channel_open = 0;
if (workqueue == NULL) {
if ((workqueue = create_singlethread_workqueue("kspd")) == NULL) {
printk(KERN_ERR "unable to start kspd\n");
return;
}
INIT_WORK(&work, sp_work);
queue_work(workqueue, &work);
} else
queue_work(workqueue, &work);
}
static void stopwork(int vpe)
{
sp_stopping = 1;
printk(KERN_DEBUG "KSPD: SP stopping\n");
}
void kspd_notify(struct kspd_notifications *notify)
{
list_add(¬ify->list, &kspd_notifylist);
}
static struct vpe_notifications notify;
static int kspd_module_init(void)
{
INIT_LIST_HEAD(&kspd_notifylist);
notify.start = startwork;
notify.stop = stopwork;
vpe_notify(SP_VPE, ¬ify);
return 0;
}
static void kspd_module_exit(void)
{
}
module_init(kspd_module_init);
module_exit(kspd_module_exit);
MODULE_DESCRIPTION("MIPS KSPD");
MODULE_AUTHOR("Elizabeth Oldham, MIPS Technologies, Inc.");
MODULE_LICENSE("GPL");
