[MIPS] kpsd and other AP/SP improvements.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/Kconfig

@@ -1476,6 +1476,16 @@ config MIPS_VPE_APSP_API
 	depends on MIPS_VPE_LOADER
 	help
 
+config MIPS_APSP_KSPD
+	bool "Enable KSPD"
+	depends on MIPS_VPE_APSP_API
+	default y
+	help
+	  KSPD is a kernel daemon that accepts syscall requests from the SP
+	  side, actions them and returns the results. It also handles the
+	  "exit" syscall notifying other kernel modules the SP program is
+	  exiting.  You probably want to say yes here.
+
 config SB1_PASS_1_WORKAROUNDS
 	bool
 	depends on CPU_SB1_PASS_1

arch/mips/kernel/Makefile

@@ -36,6 +36,7 @@ obj-$(CONFIG_SMP)		+= smp.o
 
 obj-$(CONFIG_MIPS_MT_SMP)	+= smp_mt.o
 
+obj-$(CONFIG_MIPS_APSP_KSPD)	+= kspd.o
 obj-$(CONFIG_MIPS_VPE_LOADER)	+= vpe.o
 obj-$(CONFIG_MIPS_VPE_APSP_API)	+= rtlx.o
 

arch/mips/kernel/kspd.c

+/*
+ * 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_fdset || 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(void *data)
+{
+	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, NULL);
+		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(&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(SP_VPE, &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");

arch/mips/kernel/rtlx.c

@@ -21,45 +21,44 @@
 #include <linux/module.h>
 #include <linux/fs.h>
 #include <linux/init.h>
+#include <asm/uaccess.h>
+#include <linux/slab.h>
+#include <linux/list.h>
+#include <linux/vmalloc.h>
+#include <linux/elf.h>
+#include <linux/seq_file.h>
+#include <linux/syscalls.h>
+#include <linux/moduleloader.h>
 #include <linux/interrupt.h>
-#include <linux/irq.h>
 #include <linux/poll.h>
 #include <linux/sched.h>
 #include <linux/wait.h>
-
 #include <asm/mipsmtregs.h>
-#include <asm/bitops.h>
+#include <asm/cacheflush.h>
+#include <asm/atomic.h>
 #include <asm/cpu.h>
 #include <asm/processor.h>
+#include <asm/system.h>
+#include <asm/vpe.h>
 #include <asm/rtlx.h>
-#include <asm/uaccess.h>
 
 #define RTLX_TARG_VPE 1
 
 static struct rtlx_info *rtlx;
 static int major;
 static char module_name[] = "rtlx";
-static struct irqaction irq;
-static int irq_num;
-
-static inline int spacefree(int read, int write, int size)
-{
-	if (read == write) {
-		/*
-		 * never fill the buffer completely, so indexes are always
-		 * equal if empty and only empty, or !equal if data available
-		 */
-		return size - 1;
-	}
-
-	return ((read + size - write) % size) - 1;
-}
 
 static struct chan_waitqueues {
 	wait_queue_head_t rt_queue;
 	wait_queue_head_t lx_queue;
+	int in_open;
 } channel_wqs[RTLX_CHANNELS];
 
+static struct irqaction irq;
+static int irq_num;
+static struct vpe_notifications notify;
+static int sp_stopping = 0;
+
 extern void *vpe_get_shared(int index);
 
 static void rtlx_dispatch(struct pt_regs *regs)
@@ -67,174 +66,298 @@ static void rtlx_dispatch(struct pt_regs *regs)
 	do_IRQ(MIPSCPU_INT_BASE + MIPS_CPU_RTLX_IRQ, regs);
 }
 
+
+/* Interrupt handler may be called before rtlx_init has otherwise had
+   a chance to run.
+*/
 static irqreturn_t rtlx_interrupt(int irq, void *dev_id, struct pt_regs *regs)
 {
 	int i;
 
 	for (i = 0; i < RTLX_CHANNELS; i++) {
-		struct rtlx_channel *chan = &rtlx->channel[i];
-
-		if (chan->lx_read != chan->lx_write)
-			wake_up_interruptible(&channel_wqs[i].lx_queue);
+			wake_up(&channel_wqs[i].lx_queue);
+			wake_up(&channel_wqs[i].rt_queue);
 	}
 
 	return IRQ_HANDLED;
 }
 
-/* call when we have the address of the shared structure from the SP side. */
-static int rtlx_init(struct rtlx_info *rtlxi)
+static __attribute_used__ void dump_rtlx(void)
 {
 	int i;
 
-	if (rtlxi->id != RTLX_ID) {
-		printk(KERN_WARNING "no valid RTLX id at 0x%p\n", rtlxi);
-		return -ENOEXEC;
-	}
+	printk("id 0x%lx state %d\n", rtlx->id, rtlx->state);
 
-	/* initialise the wait queues */
 	for (i = 0; i < RTLX_CHANNELS; i++) {
-		init_waitqueue_head(&channel_wqs[i].rt_queue);
-		init_waitqueue_head(&channel_wqs[i].lx_queue);
-	}
+		struct rtlx_channel *chan = &rtlx->channel[i];
 
-	/* set up for interrupt handling */
-	memset(&irq, 0, sizeof(struct irqaction));
+		printk(" rt_state %d lx_state %d buffer_size %d\n",
+		       chan->rt_state, chan->lx_state, chan->buffer_size);
 
-	if (cpu_has_vint)
-		set_vi_handler(MIPS_CPU_RTLX_IRQ, rtlx_dispatch);
+		printk(" rt_read %d rt_write %d\n",
+		       chan->rt_read, chan->rt_write);
 
-	irq_num = MIPSCPU_INT_BASE + MIPS_CPU_RTLX_IRQ;
-	irq.handler = rtlx_interrupt;
-	irq.flags = SA_INTERRUPT;
-	irq.name = "RTLX";
-	irq.dev_id = rtlx;
-	setup_irq(irq_num, &irq);
+		printk(" lx_read %d lx_write %d\n",
+		       chan->lx_read, chan->lx_write);
+
+		printk(" rt_buffer <%s>\n", chan->rt_buffer);
+		printk(" lx_buffer <%s>\n", chan->lx_buffer);
+	}
+}
+
+/* call when we have the address of the shared structure from the SP side. */
+static int rtlx_init(struct rtlx_info *rtlxi)
+{
+	if (rtlxi->id != RTLX_ID) {
+		printk(KERN_ERR "no valid RTLX id at 0x%p 0x%x\n", rtlxi, rtlxi->id);
+		return -ENOEXEC;
+	}
 
 	rtlx = rtlxi;
 
 	return 0;
 }
 
-/* only allow one open process at a time to open each channel */
-static int rtlx_open(struct inode *inode, struct file *filp)
+/* notifications */
+static void starting(int vpe)
 {
-	int minor, ret;
+	int i;
+	sp_stopping = 0;
+
+	/* force a reload of rtlx */
+	rtlx=NULL;
+
+	/* wake up any sleeping rtlx_open's */
+	for (i = 0; i < RTLX_CHANNELS; i++)
+		wake_up_interruptible(&channel_wqs[i].lx_queue);
+}
+
+static void stopping(int vpe)
+{
+	int i;
+
+	sp_stopping = 1;
+	for (i = 0; i < RTLX_CHANNELS; i++)
+		wake_up_interruptible(&channel_wqs[i].lx_queue);
+}
+
+
+int rtlx_open(int index, int can_sleep)
+{
+	int ret;
 	struct rtlx_channel *chan;
+	volatile struct rtlx_info **p;
 
-	/* assume only 1 device at the mo. */
-	minor = MINOR(inode->i_rdev);
+	if (index >= RTLX_CHANNELS) {
+		printk(KERN_DEBUG "rtlx_open index out of range\n");
+		return -ENOSYS;
+	}
+
+	if (channel_wqs[index].in_open) {
+		printk(KERN_DEBUG "rtlx_open channel %d already opened\n", index);
+		return -EBUSY;
+	}
+
+	channel_wqs[index].in_open++;
 
 	if (rtlx == NULL) {
-		struct rtlx_info **p;
 		if( (p = vpe_get_shared(RTLX_TARG_VPE)) == NULL) {
-			printk(KERN_ERR "vpe_get_shared is NULL. "
-			       "Has an SP program been loaded?\n");
-			return -EFAULT;
+			if (can_sleep) {
+				DECLARE_WAITQUEUE(wait, current);
+
+				/* go to sleep */
+				add_wait_queue(&channel_wqs[index].lx_queue, &wait);