microblaze_v8: IPC support

Reviewed-by: Ingo Molnar <mingo@elte.hu>
Acked-by: John Linn <john.linn@xilinx.com>
Acked-by: Stephen Neuendorffer <stephen.neuendorffer@xilinx.com>
Acked-by: John Williams <john.williams@petalogix.com>
Signed-off-by: Michal Simek <monstr@monstr.eu>
diff --git a/arch/microblaze/kernel/sys_microblaze.c b/arch/microblaze/kernel/sys_microblaze.c
new file mode 100644
index 0000000..d90b548
--- /dev/null
+++ b/arch/microblaze/kernel/sys_microblaze.c
@@ -0,0 +1,227 @@
+/*
+ * Copyright (C) 2007-2009 Michal Simek <monstr@monstr.eu>
+ * Copyright (C) 2007-2009 PetaLogix
+ * Copyright (C) 2007 John Williams <john.williams@petalogix.com>
+ *
+ * Copyright (C) 2006 Atmark Techno, Inc.
+ *	Yasushi SHOJI <yashi@atmark-techno.com>
+ *	Tetsuya OHKAWA <tetsuya@atmark-techno.com>
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#include <linux/errno.h>
+#include <linux/mm.h>
+#include <linux/smp.h>
+#include <linux/smp_lock.h>
+#include <linux/syscalls.h>
+#include <linux/sem.h>
+#include <linux/msg.h>
+#include <linux/shm.h>
+#include <linux/stat.h>
+#include <linux/mman.h>
+#include <linux/sys.h>
+#include <linux/ipc.h>
+#include <linux/utsname.h>
+#include <linux/file.h>
+#include <linux/module.h>
+#include <linux/err.h>
+#include <linux/fs.h>
+#include <linux/ipc.h>
+#include <linux/semaphore.h>
+#include <linux/syscalls.h>
+#include <linux/uaccess.h>
+#include <linux/unistd.h>
+
+#include <asm/syscalls.h>
+/*
+ * sys_ipc() is the de-multiplexer for the SysV IPC calls..
+ *
+ * This is really horribly ugly. This will be remove with new toolchain.
+ */
+asmlinkage int
+sys_ipc(uint call, int first, int second, int third, void *ptr, long fifth)
+{
+	int version, ret;
+
+	version = call >> 16; /* hack for backward compatibility */
+	call &= 0xffff;
+
+	ret = -EINVAL;
+	switch (call) {
+	case SEMOP:
+		ret = sys_semop(first, (struct sembuf *)ptr, second);
+		break;
+	case SEMGET:
+		ret = sys_semget(first, second, third);
+		break;
+	case SEMCTL:
+	{
+		union semun fourth;
+
+		if (!ptr)
+			break;
+		ret = (access_ok(VERIFY_READ, ptr, sizeof(long)) ? 0 : -EFAULT)
+				|| (get_user(fourth.__pad, (void **)ptr)) ;
+		if (ret)
+			break;
+		ret = sys_semctl(first, second, third, fourth);
+		break;
+	}
+	case MSGSND:
+		ret = sys_msgsnd(first, (struct msgbuf *) ptr, second, third);
+		break;
+	case MSGRCV:
+		switch (version) {
+		case 0: {
+			struct ipc_kludge tmp;
+
+			if (!ptr)
+				break;
+			ret = (access_ok(VERIFY_READ, ptr, sizeof(tmp))
+				? 0 : -EFAULT) || copy_from_user(&tmp,
+				(struct ipc_kludge *) ptr, sizeof(tmp));
+			if (ret)
+				break;
+			ret = sys_msgrcv(first, tmp.msgp, second, tmp.msgtyp,
+					third);
+			break;
+			}
+		default:
+			ret = sys_msgrcv(first, (struct msgbuf *) ptr,
+					second, fifth, third);
+			break;
+		}
+		break;
+	case MSGGET:
+		ret = sys_msgget((key_t) first, second);
+		break;
+	case MSGCTL:
+		ret = sys_msgctl(first, second, (struct msqid_ds *) ptr);
+		break;
+	case SHMAT:
+		switch (version) {
+		default: {
+			ulong raddr;
+			ret = access_ok(VERIFY_WRITE, (ulong *) third,
+					sizeof(ulong)) ? 0 : -EFAULT;
+			if (ret)
+				break;
+			ret = do_shmat(first, (char *) ptr, second, &raddr);
+			if (ret)
+				break;
+			ret = put_user(raddr, (ulong *) third);
+			break;
+			}
+		case 1:	/* iBCS2 emulator entry point */
+			if (!segment_eq(get_fs(), get_ds()))
+				break;
+			ret = do_shmat(first, (char *) ptr, second,
+					(ulong *) third);
+			break;
+		}
+		break;
+	case SHMDT:
+		ret = sys_shmdt((char *)ptr);
+		break;
+	case SHMGET:
+		ret = sys_shmget(first, second, third);
+		break;
+	case SHMCTL:
+		ret = sys_shmctl(first, second, (struct shmid_ds *) ptr);
+		break;
+	}
+	return -EINVAL;
+}
+
+asmlinkage int sys_vfork(struct pt_regs *regs)
+{
+	return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->r1,
+						regs, 0, NULL, NULL);
+}
+
+asmlinkage int sys_clone(int flags, unsigned long stack, struct pt_regs *regs)
+{
+	if (!stack)
+		stack = regs->r1;
+	return do_fork(flags, stack, regs, 0, NULL, NULL);
+}
+
+asmlinkage int sys_execve(char __user *filenamei, char __user *__user *argv,
+			char __user *__user *envp, struct pt_regs *regs)
+{
+	int error;
+	char *filename;
+
+	filename = getname(filenamei);
+	error = PTR_ERR(filename);
+	if (IS_ERR(filename))
+		goto out;
+	error = do_execve(filename, argv, envp, regs);
+	putname(filename);
+out:
+	return error;
+}
+
+asmlinkage unsigned long
+sys_mmap2(unsigned long addr, size_t len,
+	unsigned long prot, unsigned long flags,
+	unsigned long fd, unsigned long pgoff)
+{
+	struct file *file = NULL;
+	int ret = -EBADF;
+
+	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
+	if (!(flags & MAP_ANONYMOUS)) {
+		file = fget(fd);
+		if (!file) {
+			printk(KERN_INFO "no fd in mmap\r\n");
+			goto out;
+		}
+	}
+
+	down_write(&current->mm->mmap_sem);
+	ret = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
+	up_write(&current->mm->mmap_sem);
+	if (file)
+		fput(file);
+out:
+	return ret;
+}
+
+asmlinkage unsigned long sys_mmap(unsigned long addr, size_t len,
+			unsigned long prot, unsigned long flags,
+			unsigned long fd, off_t offset)
+{
+	int err = -EINVAL;
+
+	if (offset & ~PAGE_MASK) {
+		printk(KERN_INFO "no pagemask in mmap\r\n");
+		goto out;
+	}
+
+	err = sys_mmap2(addr, len, prot, flags, fd, offset >> PAGE_SHIFT);
+out:
+	return err;
+}
+
+/*
+ * Do a system call from kernel instead of calling sys_execve so we
+ * end up with proper pt_regs.
+ */
+int kernel_execve(const char *filename, char *const argv[], char *const envp[])
+{
+	register const char *__a __asm__("r5") = filename;
+	register const void *__b __asm__("r6") = argv;
+	register const void *__c __asm__("r7") = envp;
+	register unsigned long __syscall __asm__("r12") = __NR_execve;
+	register unsigned long __ret __asm__("r3");
+	__asm__ __volatile__ ("brki r14, 0x8"
+			: "=r" (__ret), "=r" (__syscall)
+			: "1" (__syscall), "r" (__a), "r" (__b), "r" (__c)
+			: "r4", "r8", "r9",
+			"r10", "r11", "r14", "cc", "memory");
+	return __ret;
+}