xfs: introduce new logging API.

Most of the logging infrastructure in XFS is unneccessary and
designed around the infrastructure supplied by Irix rather than
Linux. To rationalise the logging interfaces, start by introducing
simple printk wrappers similar to the dev_printk() infrastructure.
Later patches will convert code to use this new interface.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Alex Elder <aelder@sgi.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>

fs/xfs/Makefile

@@ -105,6 +105,7 @@ xfs-y				+= $(addprefix $(XFS_LINUX)/, \
 				   xfs_globals.o \
 				   xfs_ioctl.o \
 				   xfs_iops.o \
+				   xfs_message.o \
 				   xfs_super.o \
 				   xfs_sync.o \
 				   xfs_xattr.o)

fs/xfs/linux-2.6/xfs_linux.h

@@ -86,6 +86,7 @@
 #include <xfs_aops.h>
 #include <xfs_super.h>
 #include <xfs_buf.h>
+#include <xfs_message.h>
 
 /*
  * Feature macros (disable/enable)

fs/xfs/linux-2.6/xfs_message.c

@@ -0,0 +1,119 @@
+/*
+ * Copyright (c) 2011 Red Hat, Inc.  All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would 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 the Free Software Foundation,
+ * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#include "xfs.h"
+#include "xfs_fs.h"
+#include "xfs_types.h"
+#include "xfs_log.h"
+#include "xfs_inum.h"
+#include "xfs_trans.h"
+#include "xfs_sb.h"
+#include "xfs_ag.h"
+#include "xfs_mount.h"
+
+/*
+ * XFS logging functions
+ */
+static int
+__xfs_printk(
+	const char		*level,
+	const struct xfs_mount	*mp,
+	struct va_format	*vaf)
+{
+	if (mp && mp->m_fsname)
+		return printk("%sXFS (%s): %pV\n", level, mp->m_fsname, vaf);
+	return printk("%sXFS: %pV\n", level, vaf);
+}
+
+int xfs_printk(
+	const char		*level,
+	const struct xfs_mount	*mp,
+	const char		*fmt, ...)
+{
+	struct va_format	vaf;
+	va_list			args;
+	int			 r;
+
+	va_start(args, fmt);
+
+	vaf.fmt = fmt;
+	vaf.va = &args;
+
+	r = __xfs_printk(level, mp, &vaf);
+	va_end(args);
+
+	return r;
+}
+
+#define define_xfs_printk_level(func, kern_level)		\
+int func(const struct xfs_mount *mp, const char *fmt, ...)	\
+{								\
+	struct va_format	vaf;				\
+	va_list			args;				\
+	int			r;				\
+								\
+	va_start(args, fmt);					\
+								\
+	vaf.fmt = fmt;						\
+	vaf.va = &args;						\
+								\
+	r = __xfs_printk(kern_level, mp, &vaf);			\
+	va_end(args);						\
+								\
+	return r;						\
+}								\
+
+define_xfs_printk_level(xfs_emerg, KERN_EMERG);
+define_xfs_printk_level(xfs_alert, KERN_ALERT);
+define_xfs_printk_level(xfs_crit, KERN_CRIT);
+define_xfs_printk_level(xfs_err, KERN_ERR);
+define_xfs_printk_level(xfs_warn, KERN_WARNING);
+define_xfs_printk_level(xfs_notice, KERN_NOTICE);
+define_xfs_printk_level(xfs_info, KERN_INFO);
+#ifdef DEBUG
+define_xfs_printk_level(xfs_debug, KERN_DEBUG);
+#endif
+
+int
+xfs_alert_tag(
+	const struct xfs_mount	*mp,
+	int			panic_tag,
+	const char		*fmt, ...)
+{
+	struct va_format	vaf;
+	va_list			args;
+	int			panic = 0;
+	int			 r;
+
+	if (xfs_panic_mask && (xfs_panic_mask & panic_tag)) {
+		xfs_printk(KERN_ALERT, mp,
+			"XFS: Transforming an alert into a BUG.");
+		panic = 1;
+	}
+
+	va_start(args, fmt);
+
+	vaf.fmt = fmt;
+	vaf.va = &args;
+
+	r = __xfs_printk(KERN_ALERT, mp, &vaf);
+	va_end(args);
+
+	BUG_ON(panic);
+
+	return r;
+}

fs/xfs/linux-2.6/xfs_message.h

@@ -0,0 +1,34 @@
+#ifndef __XFS_MESSAGE_H
+#define __XFS_MESSAGE_H 1
+
+struct xfs_mount;
+
+extern int xfs_printk(const char *level, const struct xfs_mount *mp,
+                      const char *fmt, ...)
+        __attribute__ ((format (printf, 3, 4)));
+extern int xfs_emerg(const struct xfs_mount *mp, const char *fmt, ...)
+        __attribute__ ((format (printf, 2, 3)));
+extern int xfs_alert(const struct xfs_mount *mp, const char *fmt, ...)
+        __attribute__ ((format (printf, 2, 3)));
+extern int xfs_alert_tag(const struct xfs_mount *mp, int tag,
+			 const char *fmt, ...)
+        __attribute__ ((format (printf, 3, 4)));
+extern int xfs_crit(const struct xfs_mount *mp, const char *fmt, ...)
+        __attribute__ ((format (printf, 2, 3)));
+extern int xfs_err(const struct xfs_mount *mp, const char *fmt, ...)
+        __attribute__ ((format (printf, 2, 3)));
+extern int xfs_warn(const struct xfs_mount *mp, const char *fmt, ...)
+        __attribute__ ((format (printf, 2, 3)));
+extern int xfs_notice(const struct xfs_mount *mp, const char *fmt, ...)
+        __attribute__ ((format (printf, 2, 3)));
+extern int xfs_info(const struct xfs_mount *mp, const char *fmt, ...)
+        __attribute__ ((format (printf, 2, 3)));
+
+#ifdef DEBUG
+extern int xfs_debug(const struct xfs_mount *mp, const char *fmt, ...)
+        __attribute__ ((format (printf, 2, 3)));
+#else
+#define xfs_debug(mp, fmt, ...)	(0)
+#endif
+
+#endif	/* __XFS_MESSAGE_H */