/*-
* Copyright (c) 2011, 2012, 2013, 2014 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)
*/
/**
* \file zfsd.h
*
* Class definitions and supporting data strutures for the ZFS fault
* management daemon.
*
* Header requirements:
*
* #include <sys/fs/zfs.h>
*
* #include <libzfs.h>
*
* #include <list>
* #include <map>
* #include <string>
*
* #include <devdctl/guid.h>
* #include <devdctl/event.h>
* #include <devdctl/event_factory.h>
* #include <devdctl/consumer.h>
*
* #include "vdev_iterator.h"
*/
#ifndef _ZFSD_H_
#define _ZFSD_H_
/*=========================== Forward Declarations ===========================*/
struct pidfh;
struct zpool_handle;
typedef struct zpool_handle zpool_handle_t;
struct zfs_handle;
typedef struct libzfs_handle libzfs_handle_t;
struct nvlist;
typedef struct nvlist nvlist_t;
typedef int LeafIterFunc(zpool_handle_t *, nvlist_t *, void *);
/*================================ Global Data ===============================*/
extern int g_debug;
extern libzfs_handle_t *g_zfsHandle;
/*============================= Class Definitions ============================*/
/*--------------------------------- ZfsDaemon --------------------------------*/
/**
* Static singleton orchestrating the operations of the ZFS daemon program.
*/
class ZfsDaemon : public DevdCtl::Consumer
{
public:
/** Return the ZfsDaemon singleton. */
static ZfsDaemon &Get();
/**
* Used by signal handlers to ensure, in a race free way, that
* the event loop will perform at least one more full loop
* before sleeping again.
*/
static void WakeEventLoop();
/**
* Schedules a rescan of devices in the system for potential
* candidates to replace a missing vdev. The scan is performed
* during the next run of the event loop.
*/
static void RequestSystemRescan();
/** Daemonize and perform all functions of the ZFS daemon. */
static void Run();
private:
ZfsDaemon();
~ZfsDaemon();
static VdevCallback_t VdevAddCaseFile;
/** Purge our cache of outstanding ZFS issues in the system. */
void PurgeCaseFiles();
/** Build a cache of outstanding ZFS issues in the system. */
void BuildCaseFiles();
/**
* Iterate over all known issues and attempt to solve them
* given resources currently available in the system.
*/
void RescanSystem();
/**
* Interrogate the system looking for previously unknown
* faults that occurred either before ZFSD was started,
* or during a period of lost communication with Devd.
*/
void DetectMissedEvents();
/**
* Wait for and process event source activity.
*/
void EventLoop();
/**
* Signal handler for which our response is to
* log the current state of the daemon.
*
* \param sigNum The signal caught.
*/
static void InfoSignalHandler(int sigNum);
/**
* Signal handler for which our response is to
* request a case rescan.
*
* \param sigNum The signal caught.
*/
static void RescanSignalHandler(int sigNum);
/**
* Signal handler for which our response is to
* gracefully terminate.
*
* \param sigNum The signal caught.
*/
static void QuitSignalHandler(int sigNum);
/**
* Open and lock our PID file.
*/
static void OpenPIDFile();
/**
* Update our PID file with our PID.
*/
static void UpdatePIDFile();
/**
* Close and release the lock on our PID file.
*/
static void ClosePIDFile();
/**
* Perform syslog configuration.
*/
static void InitializeSyslog();
static ZfsDaemon *s_theZfsDaemon;
/**
* Set to true when our program is signaled to
* gracefully exit.
*/
static bool s_logCaseFiles;
/**
* Set to true when our program is signaled to
* gracefully exit.
*/
static bool s_terminateEventLoop;
/**
* The canonical path and file name of zfsd's PID file.
*/
static char s_pidFilePath[];
/**
* Control structure for PIDFILE(3) API.
*/
static pidfh *s_pidFH;
/**
* Pipe file descriptors used to close races with our
* signal handlers.
*/
static int s_signalPipeFD[2];
/**
* Flag controlling a rescan from ZFSD's event loop of all
* GEOM providers in the system to find candidates for solving
* cases.
*/
static bool s_systemRescanRequested;
/**
* Flag controlling whether events can be queued. This boolean
* is set during event replay to ensure that events for pools or
* devices no longer in the system are not retained forever.
*/
static bool s_consumingEvents;
static DevdCtl::EventFactory::Record s_registryEntries[];
};
#endif /* _ZFSD_H_ */
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