zfsd(8), the ZFS fault management daemon

Add zfsd, which deals with hard drive faults in ZFS pools. It manages
hotspares and replements in drive slots that publish physical paths.

cddl/usr.sbin/zfsd
	Add zfsd(8) and its unit tests

cddl/usr.sbin/Makefile
	Add zfsd to the build

lib/libdevdctl
	A C++ library that helps devd clients process events

lib/Makefile
share/mk/bsd.libnames.mk
share/mk/src.libnames.mk
	Add libdevdctl to the build. It's a private library, unusable by
	out-of-tree software.

etc/defaults/rc.conf
	By default, set zfsd_enable to NO

etc/mtree/BSD.include.dist
	Add a directory for libdevdctl's include files

etc/mtree/BSD.tests.dist
	Add a directory for zfsd's unit tests

etc/mtree/BSD.var.dist
	Add /var/db/zfsd/cases, where zfsd stores case files while it's shut
	down.

etc/rc.d/Makefile
etc/rc.d/zfsd
	Add zfsd's rc script

sys/cddl/contrib/opensolaris/uts/common/fs/zfs/vdev.c
	Fix the resource.fs.zfs.statechange message. It had a number of
	problems:

	It was only being emitted on a transition to the HEALTHY state.
	That made it impossible for zfsd to take actions based on drives
	getting sicker.

	It compared the new state to vdev_prevstate, which is the state that
	the vdev had the last time it was opened.  That doesn't make sense,
	because a vdev can change state multiple times without being
	reopened.

	vdev_set_state contains logic that will change the device's new
	state based on various conditions.  However, the statechange event
	was being posted _before_ that logic took effect.  Now it's being
	posted after.

Submitted by:	gibbs, asomers, mav, allanjude
Reviewed by:	mav, delphij
Relnotes:	yes
Sponsored by:	Spectra Logic Corp, iX Systems
Differential Revision:	https://reviews.freebsd.org/D6564

1 files changed, 168 insertions, 0 deletions

diff --git a/lib/libdevdctl/exception.h b/lib/libdevdctl/exception.h
new file mode 100644
index 0000000..9f4403c
--- /dev/null
+++ b/lib/libdevdctl/exception.h
@@ -0,0 +1,168 @@
+/*-
+ * Copyright (c) 2011, 2012, 2013 Spectra Logic Corporation
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions, and the following disclaimer,
+ *    without modification.
+ * 2. Redistributions in binary form must reproduce at minimum a disclaimer
+ *    substantially similar to the "NO WARRANTY" disclaimer below
+ *    ("Disclaimer") and any redistribution must be conditioned upon
+ *    including a substantially similar Disclaimer requirement for further
+ *    binary redistribution.
+ *
+ * NO WARRANTY
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGES.
+ *
+ * Authors: Justin T. Gibbs     (Spectra Logic Corporation)
+ *
+ * $FreeBSD$
+ */
+
+/**
+ * \file zfsd_exception.h
+ *
+ * Definition of the ZfsdException class hierarchy.  All exceptions
+ * explicitly thrown by Zfsd are defined here.
+ */
+#ifndef	_DEVDCTL_EXCEPTION_H_
+#define	_DEVDCTL_EXCEPTION_H_
+
+/*============================ Namespace Control =============================*/
+namespace DevdCtl
+{
+
+/*============================= Class Definitions ============================*/
+
+/*--------------------------------- Exception --------------------------------*/
+/**
+ * \brief Class allowing unified reporting/logging of exceptional events.
+ */
+class Exception
+{
+public:
+	/**
+	 * \brief Exception constructor allowing arbitrary string
+	 *        data to be reported.
+	 *
+	 * \param fmt  Printf-like string format specifier.
+	 */
+	Exception(const char *fmt, ...);
+
+	/**
+	 * \brief Augment/Modify a Exception's string data.
+	 */
+	std::string& GetString();
+
+	/**
+	 * \brief Emit exception data to syslog(3).
+	 */
+	virtual void Log() const;
+
+protected:
+	Exception();
+
+	/**
+	 * \brief Convert exception string format and arguments provided
+	 *        in event constructors into a linear string.
+	 */
+	void FormatLog(const char *fmt, va_list ap);
+
+	std::string   m_log;
+};
+
+inline std::string &
+Exception::GetString()
+{
+	return (m_log);
+}
+
+/*------------------------------ ParseException ------------------------------*/
+/**
+ * Exception thrown when an event string is not converted to an actionable
+ * Event object.
+ */
+class ParseException : public Exception
+{
+public:
+	enum Type
+	{
+		/** Improperly formatted event string encountered. */
+		INVALID_FORMAT,
+
+		/** No handlers for this event type. */
+		DISCARDED_EVENT_TYPE,
+
+		/** Unhandled event type. */
+		UNKNOWN_EVENT_TYPE
+	};
+
+	/**
+	 * Constructor
+	 *
+	 * \param type          The type of this exception.
+	 * \param parsedBuffer  The parsing buffer active at the time of
+	 *                      the exception.
+	 * \param offset        The location in the parse buffer where this
+	 *                      exception occurred.
+	 */
+	ParseException(Type type, const std::string &parsedBuffer,
+		       size_t offset = 0);
+
+	/**
+	 * Accessor
+	 *
+	 * \return  The classification for this exception.
+	 */
+	Type        GetType()   const;
+
+	/**
+	 * Accessor
+	 *
+	 * \return  The offset into the event string where this exception
+	 *          occurred.
+	 */
+	size_t      GetOffset() const;
+
+private:
+	/** The type of this exception. */
+	Type              m_type;
+
+	/** The parsing buffer that was active at the time of the exception. */
+	const std::string m_parsedBuffer;
+
+	/**
+	 * The offset into the event string buffer from where this
+	 * exception was triggered.
+	 */
+	size_t            m_offset;
+};
+
+//- ParseException Inline Const Public Methods ---------------------------------
+inline ParseException::Type
+ParseException::GetType() const
+{
+	return (m_type);
+}
+
+inline size_t
+ParseException::GetOffset() const
+{
+	return (m_offset);
+}
+
+} // namespace DevdCtl
+#endif /* _DEVDCTL_EXCEPTION_H_ */