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-rw-r--r--arch/mips/kernel/kspd.c423
1 files changed, 423 insertions, 0 deletions
diff --git a/arch/mips/kernel/kspd.c b/arch/mips/kernel/kspd.c
new file mode 100644
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--- /dev/null
+++ b/arch/mips/kernel/kspd.c
@@ -0,0 +1,423 @@
+/*
+ * 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/sched.h>
+#include <linux/unistd.h>
+#include <linux/file.h>
+#include <linux/fdtable.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;
+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;
+
+/* 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_SYSCALL_IOCTL (MTSP_SYSCALL_BASE + 10)
+
+#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
+/* XXX: check which of these is actually O_SYNC vs O_DSYNC */
+#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
+
+extern int tclimit;
+
+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 },
+ { MTSP_SYSCALL_IOCTL, __NR_ioctl }
+};
+
+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 < ARRAY_SIZE(open_flags_table); i++) {
+ if( (flags & open_flags_table[i].sp) ) {
+ ret |= open_flags_table[i].ap;
+ }
+ }
+
+ return ret;
+}
+
+
+static int sp_setfsuidgid(uid_t uid, gid_t gid)
+{
+ struct cred *new;
+
+ new = prepare_creds();
+ if (!new)
+ return -ENOMEM;
+
+ new->fsuid = uid;
+ new->fsgid = gid;
+
+ commit_creds(new);
+
+ return 0;
+}
+
+/*
+ * 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;
+ unsigned long written;
+ mm_segment_t old_fs;
+ struct timeval tv;
+ struct timezone tz;
+ int err, cmd;
+
+ char *vcwd;
+ int size;
+
+ ret.retval = -1;
+
+ old_fs = get_fs();
+ set_fs(KERNEL_DS);
+
+ if (!rtlx_read(RTLX_CHANNEL_SYSIO, &sc, sizeof(struct mtsp_syscall))) {
+ set_fs(old_fs);
+ printk(KERN_ERR "Expected request but nothing to read\n");
+ return;
+ }
+
+ size = sc.size;
+
+ if (size) {
+ if (!rtlx_read(RTLX_CHANNEL_SYSIO, &generic, size)) {
+ set_fs(old_fs);
+ printk(KERN_ERR "Expected request but nothing to read\n");
+ return;
+ }
+ }
+
+ /* Run the syscall at the privilege of the user who loaded the
+ SP program */
+
+ if (vpe_getuid(tclimit)) {
+ err = sp_setfsuidgid(vpe_getuid(tclimit), vpe_getgid(tclimit));
+ if (!err)
+ pr_err("Change of creds failed\n");
+ }
+
+ 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;
+ break;
+
+ case MTSP_SYSCALL_EXIT:
+ list_for_each_entry(n, &kspd_notifylist, list)
+ n->kspd_sp_exit(tclimit);
+ 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(tclimit);
+
+ /* change to 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);
+ } else
+ printk(KERN_WARNING
+ "KSPD: Unknown SP syscall number %d\n", sc.cmd);
+ break;
+ } /* switch */
+
+ if (vpe_getuid(tclimit)) {
+ err = sp_setfsuidgid(0, 0);
+ if (!err)
+ pr_err("restoring old creds failed\n");
+ }
+
+ old_fs = get_fs();
+ set_fs(KERNEL_DS);
+ written = rtlx_write(RTLX_CHANNEL_SYSIO, &ret, sizeof(ret));
+ set_fs(old_fs);
+ if (written < sizeof(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;
+ }
+ }
+
+ /* Put daemon cwd back to root to avoid umount problems */
+ sys_chdir("/");
+}
+
+static int channel_open;
+
+/* 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);
+}
+
+static void stopwork(int vpe)
+{
+ sp_stopping = 1;
+
+ printk(KERN_DEBUG "KSPD: SP stopping\n");
+}
+
+void kspd_notify(struct kspd_notifications *notify)
+{
+ list_add(&notify->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(tclimit, &notify);
+
+ 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");