OpenZFS 7431 - ZFS Channel Programs

Authored by: Chris Williamson <chris.williamson@delphix.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: John Kennedy <john.kennedy@delphix.com>
Reviewed by: Dan Kimmel <dan.kimmel@delphix.com>
Approved by: Garrett D'Amore <garrett@damore.org>
Ported-by: Don Brady <don.brady@delphix.com>
Ported-by: John Kennedy <john.kennedy@delphix.com>

OpenZFS-issue: https://www.illumos.org/issues/7431
OpenZFS-commit: https://github.com/openzfs/openzfs/commit/dfc11533

Porting Notes:
* The CLI long option arguments for '-t' and '-m' don't parse on linux
* Switched from kmem_alloc to vmem_alloc in zcp_lua_alloc
* Lua implementation is built as its own module (zlua.ko)
* Lua headers consumed directly by zfs code moved to 'include/sys/lua/'
* There is no native setjmp/longjump available in stock Linux kernel.
  Brought over implementations from illumos and FreeBSD
* The get_temporary_prop() was adapted due to VFS platform differences
* Use of inline functions in lua parser to reduce stack usage per C call
* Skip some ZFS Test Suite ZCP tests on sparc64 to avoid stack overflow

module/lua/lcompat.c

@@ -0,0 +1,101 @@
+/*
+ * Copyright (c) 2016 by Delphix. All rights reserved.
+ */
+
+#include <sys/lua/lua.h>
+
+
+ssize_t
+lcompat_sprintf(char *buf, const char *fmt, ...)
+{
+	ssize_t res;
+	va_list args;
+
+	va_start(args, fmt);
+	res = vsnprintf(buf, INT_MAX, fmt, args);
+	va_end(args);
+
+	return (res);
+}
+
+int64_t
+lcompat_strtoll(const char *str, char **ptr)
+{
+	int base;
+	const char *cp;
+	int digits;
+	int64_t value;
+	boolean_t is_negative;
+
+	cp = str;
+	while (*cp == ' ' || *cp == '\t' || *cp == '\n') {
+		cp++;
+	}
+	is_negative = (*cp == '-');
+	if (is_negative) {
+		cp++;
+	}
+	base = 10;
+
+	if (*cp == '0') {
+		base = 8;
+		cp++;
+		if (*cp == 'x' || *cp == 'X') {
+			base = 16;
+			cp++;
+		}
+	}
+
+	value = 0;
+	for (; *cp != '\0'; cp++) {
+		if (*cp >= '0' && *cp <= '9') {
+			digits = *cp - '0';
+		} else if (*cp >= 'a' && *cp <= 'f') {
+			digits = *cp - 'a' + 10;
+		} else if (*cp >= 'A' && *cp <= 'F') {
+			digits = *cp - 'A' + 10;
+		} else {
+			break;
+		}
+		if (digits >= base) {
+			break;
+		}
+		value = (value * base) + digits;
+	}
+
+	if (ptr != NULL) {
+		*ptr = (char *)cp;
+	}
+	if (is_negative) {
+		value = -value;
+	}
+	return (value);
+}
+
+int64_t
+lcompat_pow(int64_t x, int64_t y)
+{
+	int64_t result = 1;
+	if (y < 0)
+		return (0);
+
+	while (y) {
+		if (y & 1)
+			result *= x;
+		y >>= 1;
+		x *= x;
+	}
+	return (result);
+}
+
+int
+lcompat_hashnum(int64_t x)
+{
+	x = (~x) + (x << 18);
+	x = x ^ (x >> 31);
+	x = x * 21;
+	x = x ^ (x >> 11);
+	x = x + (x << 6);
+	x = x ^ (x >> 22);
+	return ((int)x);
+}