diff options
Diffstat (limited to 'arch/mips/kernel/kspd.c')
-rw-r--r-- | arch/mips/kernel/kspd.c | 423 |
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 index 00000000..29811f04 --- /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(¬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(tclimit, ¬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"); |