go-libzfs/common.go

// Package zfs implements basic manipulation of ZFS pools and data sets.
// Use libzfs C library instead CLI zfs tools, with goal
// to let using and manipulating OpenZFS form with in go project.
//
// TODO: Adding to the pool. (Add the given vdevs to the pool)
// TODO: Scan for pools.
//
//
package zfs

/*
#cgo CFLAGS: -I /usr/include/libzfs -I /usr/include/libspl -DHAVE_IOCTL_IN_SYS_IOCTL_H
#cgo LDFLAGS: -lzfs -lzpool -lnvpair

#include <stdlib.h>
#include <libzfs.h>
#include "zpool.h"
#include "zfs.h"
*/
import "C"

import (
	"errors"
)

// VDevType type of device in the pool
type VDevType string

var libzfsHandle *C.struct_libzfs_handle

func init() {
	libzfsHandle = C.libzfs_init()
	return
}

// Types of Virtual Devices
const (
	VDevTypeRoot      VDevType = "root"      // VDevTypeRoot root device in ZFS pool
	VDevTypeMirror             = "mirror"    // VDevTypeMirror mirror device in ZFS pool
	VDevTypeReplacing          = "replacing" // VDevTypeReplacing replacing
	VDevTypeRaidz              = "raidz"     // VDevTypeRaidz RAIDZ device
	VDevTypeDisk               = "disk"      // VDevTypeDisk device is disk
	VDevTypeFile               = "file"      // VDevTypeFile device is file
	VDevTypeMissing            = "missing"   // VDevTypeMissing missing device
	VDevTypeHole               = "hole"      // VDevTypeHole hole
	VDevTypeSpare              = "spare"     // VDevTypeSpare spare device
	VDevTypeLog                = "log"       // VDevTypeLog ZIL device
	VDevTypeL2cache            = "l2cache"   // VDevTypeL2cache cache device (disk)
)

// Prop type to enumerate all different properties suppoerted by ZFS
type Prop int

// PoolStatus type representing status of the pool
type PoolStatus int

// PoolState type representing pool state
type PoolState uint64

// VDevState - vdev states tye
type VDevState uint64

// VDevAux - vdev aux states
type VDevAux uint64

// Property ZFS pool or dataset property value
type Property struct {
	Value  string
	Source string
}

// Pool status
const (
	/*
	 * The following correspond to faults as defined in the (fault.fs.zfs.*)
	 * event namespace.  Each is associated with a corresponding message ID.
	 */
	PoolStatusCorruptCache      PoolStatus = iota /* corrupt /kernel/drv/zpool.cache */
	PoolStatusMissingDevR                         /* missing device with replicas */
	PoolStatusMissingDevNr                        /* missing device with no replicas */
	PoolStatusCorruptLabelR                       /* bad device label with replicas */
	PoolStatusCorruptLabelNr                      /* bad device label with no replicas */
	PoolStatusBadGUIDSum                          /* sum of device guids didn't match */
	PoolStatusCorruptPool                         /* pool metadata is corrupted */
	PoolStatusCorruptData                         /* data errors in user (meta)data */
	PoolStatusFailingDev                          /* device experiencing errors */
	PoolStatusVersionNewer                        /* newer on-disk version */
	PoolStatusHostidMismatch                      /* last accessed by another system */
	PoolStatusIoFailureWait                       /* failed I/O, failmode 'wait' */
	PoolStatusIoFailureContinue                   /* failed I/O, failmode 'continue' */
	PoolStatusBadLog                              /* cannot read log chain(s) */
	PoolStatusErrata                              /* informational errata available */

	/*
	 * If the pool has unsupported features but can still be opened in
	 * read-only mode, its status is ZPOOL_STATUS_UNSUP_FEAT_WRITE. If the
	 * pool has unsupported features but cannot be opened at all, its
	 * status is ZPOOL_STATUS_UNSUP_FEAT_READ.
	 */
	PoolStatusUnsupFeatRead  /* unsupported features for read */
	PoolStatusUnsupFeatWrite /* unsupported features for write */

	/*
	 * These faults have no corresponding message ID.  At the time we are
	 * checking the status, the original reason for the FMA fault (I/O or
	 * checksum errors) has been lost.
	 */
	PoolStatusFaultedDevR  /* faulted device with replicas */
	PoolStatusFaultedDevNr /* faulted device with no replicas */

	/*
	 * The following are not faults per se, but still an error possibly
	 * requiring administrative attention.  There is no corresponding
	 * message ID.
	 */
	PoolStatusVersionOlder /* older legacy on-disk version */
	PoolStatusFeatDisabled /* supported features are disabled */
	PoolStatusResilvering  /* device being resilvered */
	PoolStatusOfflineDev   /* device online */
	PoolStatusRemovedDev   /* removed device */

	/*
	 * Finally, the following indicates a healthy pool.
	 */
	PoolStatusOk
)

// Possible ZFS pool states
const (
	PoolStateActive            PoolState = iota /* In active use		*/
	PoolStateExported                           /* Explicitly exported		*/
	PoolStateDestroyed                          /* Explicitly destroyed		*/
	PoolStateSpare                              /* Reserved for hot spare use	*/
	PoolStateL2cache                            /* Level 2 ARC device		*/
	PoolStateUninitialized                      /* Internal spa_t state		*/
	PoolStateUnavail                            /* Internal libzfs state	*/
	PoolStatePotentiallyActive                  /* Internal libzfs state	*/
)

// Pool properties. Enumerates available ZFS pool properties. Use it to access
// pool properties either to read or set soecific property.
const (
	PoolPropName Prop = iota
	PoolPropSize
	PoolPropCapacity
	PoolPropAltroot
	PoolPropHealth
	PoolPropGUID
	PoolPropVersion
	PoolPropBootfs
	PoolPropDelegation
	PoolPropAutoreplace
	PoolPropCachefile
	PoolPropFailuremode
	PoolPropListsnaps
	PoolPropAutoexpand
	PoolPropDedupditto
	PoolPropDedupratio
	PoolPropFree
	PoolPropAllocated
	PoolPropReadonly
	PoolPropAshift
	PoolPropComment
	PoolPropExpandsz
	PoolPropFreeing
	PoolPropFragmentaion
	PoolPropLeaked
	PoolPropMaxBlockSize
	PoolPropTName
	PoolNumProps
)

/*
 * Dataset properties are identified by these constants and must be added to
 * the end of this list to ensure that external consumers are not affected
 * by the change. If you make any changes to this list, be sure to update
 * the property table in module/zcommon/zfs_prop.c.
 */
const (
	DatasetPropType Prop = iota
	DatasetPropCreation
	DatasetPropUsed
	DatasetPropAvailable
	DatasetPropReferenced
	DatasetPropCompressratio
	DatasetPropMounted
	DatasetPropOrigin
	DatasetPropQuota
	DatasetPropReservation
	DatasetPropVolsize
	DatasetPropVolblocksize
	DatasetPropRecordsize
	DatasetPropMountpoint
	DatasetPropSharenfs
	DatasetPropChecksum
	DatasetPropCompression
	DatasetPropAtime
	DatasetPropDevices
	DatasetPropExec
	DatasetPropSetuid
	DatasetPropReadonly
	DatasetPropZoned
	DatasetPropSnapdir
	DatasetPropPrivate /* not exposed to user, temporary */
	DatasetPropAclinherit
	DatasetPropCreatetxg /* not exposed to the user */
	DatasetPropName      /* not exposed to the user */
	DatasetPropCanmount
	DatasetPropIscsioptions /* not exposed to the user */
	DatasetPropXattr
	DatasetPropNumclones /* not exposed to the user */
	DatasetPropCopies
	DatasetPropVersion
	DatasetPropUtf8only
	DatasetPropNormalize
	DatasetPropCase
	DatasetPropVscan
	DatasetPropNbmand
	DatasetPropSharesmb
	DatasetPropRefquota
	DatasetPropRefreservation
	DatasetPropGUID
	DatasetPropPrimarycache
	DatasetPropSecondarycache
	DatasetPropUsedsnap
	DatasetPropUsedds
	DatasetPropUsedchild
	DatasetPropUsedrefreserv
	DatasetPropUseraccounting /* not exposed to the user */
	DatasetPropStmfShareinfo  /* not exposed to the user */
	DatasetPropDeferDestroy
	DatasetPropUserrefs
	DatasetPropLogbias
	DatasetPropUnique   /* not exposed to the user */
	DatasetPropObjsetid /* not exposed to the user */
	DatasetPropDedup
	DatasetPropMlslabel
	DatasetPropSync
	DatasetPropRefratio
	DatasetPropWritten
	DatasetPropClones
	DatasetPropLogicalused
	DatasetPropLogicalreferenced
	DatasetPropInconsistent /* not exposed to the user */
	DatasetPropSnapdev
	DatasetPropAcltype
	DatasetPropSelinuxContext
	DatasetPropSelinuxFsContext
	DatasetPropSelinuxDefContext
	DatasetPropSelinuxRootContext
	DatasetPropRelatime
	DatasetPropRedundantMetadata
	DatasetPropOverlay
	DatasetNumProps
)

// LastError get last underlying libzfs error description if any
func LastError() (err error) {
	errno := C.libzfs_errno(libzfsHandle)
	if errno == 0 {
		return nil
	}
	return errors.New(C.GoString(C.libzfs_error_description(libzfsHandle)))
}

// ClearLastError force clear of any last error set by undeliying libzfs
func ClearLastError() (err error) {
	err = LastError()
	C.clear_last_error(libzfsHandle)
	return
}

func booleanT(b bool) (r C.boolean_t) {
	if b {
		return 1
	}
	return 0
}

// ZFS errors
const (
	ESuccess            = 0            /* no error -- success */
	ENomem              = 2000 << iota /* out of memory */
	EBadprop                           /* invalid property value */
	EPropreadonly                      /* cannot set readonly property */
	EProptype                          /* property does not apply to dataset type */
	EPropnoninherit                    /* property is not inheritable */
	EPropspace                         /* bad quota or reservation */
	EBadtype                           /* dataset is not of appropriate type */
	EBusy                              /* pool or dataset is busy */
	EExists                            /* pool or dataset already exists */
	ENoent                             /* no such pool or dataset */
	EBadstream                         /* bad backup stream */
	EDsreadonly                        /* dataset is readonly */
	EVoltoobig                         /* volume is too large for 32-bit system */
	EInvalidname                       /* invalid dataset name */
	EBadrestore                        /* unable to restore to destination */
	EBadbackup                         /* backup failed */
	EBadtarget                         /* bad attach/detach/replace target */
	ENodevice                          /* no such device in pool */
	EBaddev                            /* invalid device to add */
	ENoreplicas                        /* no valid replicas */
	EResilvering                       /* currently resilvering */
	EBadversion                        /* unsupported version */
	EPoolunavail                       /* pool is currently unavailable */
	EDevoverflow                       /* too many devices in one vdev */
	EBadpath                           /* must be an absolute path */
	ECrosstarget                       /* rename or clone across pool or dataset */
	EZoned                             /* used improperly in local zone */
	EMountfailed                       /* failed to mount dataset */
	EUmountfailed                      /* failed to unmount dataset */
	EUnsharenfsfailed                  /* unshare(1M) failed */
	ESharenfsfailed                    /* share(1M) failed */
	EPerm                              /* permission denied */
	ENospc                             /* out of space */
	EFault                             /* bad address */
	EIo                                /* I/O error */
	EIntr                              /* signal received */
	EIsspare                           /* device is a hot spare */
	EInvalconfig                       /* invalid vdev configuration */
	ERecursive                         /* recursive dependency */
	ENohistory                         /* no history object */
	EPoolprops                         /* couldn't retrieve pool props */
	EPoolNotsup                        /* ops not supported for this type of pool */
	EPoolInvalarg                      /* invalid argument for this pool operation */
	ENametoolong                       /* dataset name is too long */
	EOpenfailed                        /* open of device failed */
	ENocap                             /* couldn't get capacity */
	ELabelfailed                       /* write of label failed */
	EBadwho                            /* invalid permission who */
	EBadperm                           /* invalid permission */
	EBadpermset                        /* invalid permission set name */
	ENodelegation                      /* delegated administration is disabled */
	EUnsharesmbfailed                  /* failed to unshare over smb */
	ESharesmbfailed                    /* failed to share over smb */
	EBadcache                          /* bad cache file */
	EIsl2CACHE                         /* device is for the level 2 ARC */
	EVdevnotsup                        /* unsupported vdev type */
	ENotsup                            /* ops not supported on this dataset */
	EActiveSpare                       /* pool has active shared spare devices */
	EUnplayedLogs                      /* log device has unplayed logs */
	EReftagRele                        /* snapshot release: tag not found */
	EReftagHold                        /* snapshot hold: tag already exists */
	ETagtoolong                        /* snapshot hold/rele: tag too long */
	EPipefailed                        /* pipe create failed */
	EThreadcreatefailed                /* thread create failed */
	EPostsplitOnline                   /* onlining a disk after splitting it */
	EScrubbing                         /* currently scrubbing */
	ENoScrub                           /* no active scrub */
	EDiff                              /* general failure of zfs diff */
	EDiffdata                          /* bad zfs diff data */
	EPoolreadonly                      /* pool is in read-only mode */
	EUnknown
)

// vdev states are ordered from least to most healthy.
// A vdev that's VDevStateCantOpen or below is considered unusable.
const (
	VDevStateUnknown  VDevState = iota // Uninitialized vdev
	VDevStateClosed                    // Not currently open
	VDevStateOffline                   // Not allowed to open
	VDevStateRemoved                   // Explicitly removed from system
	VDevStateCantOpen                  // Tried to open, but failed
	VDevStateFaulted                   // External request to fault device
	VDevStateDegraded                  // Replicated vdev with unhealthy kids
	VDevStateHealthy                   // Presumed good
)

// vdev aux states.  When a vdev is in the VDevStateCantOpen state, the aux field
// of the vdev stats structure uses these constants to distinguish why.
const (
	VDevAuxNone         VDevAux = iota // no error
	VDevAuxOpenFailed                  // ldi_open_*() or vn_open() failed
	VDevAuxCorruptData                 // bad label or disk contents
	VDevAuxNoReplicas                  // insufficient number of replicas
	VDevAuxBadGUIDSum                  // vdev guid sum doesn't match
	VDevAuxTooSmall                    // vdev size is too small
	VDevAuxBadLabel                    // the label is OK but invalid
	VDevAuxVersionNewer                // on-disk version is too new
	VDevAuxVersionOlder                // on-disk version is too old
	VDevAuxUnsupFeat                   // unsupported features
	VDevAuxSpared                      // hot spare used in another pool
	VDevAuxErrExceeded                 // too many errors
	VDevAuxIOFailure                   // experienced I/O failure
	VDevAuxBadLog                      // cannot read log chain(s)
	VDevAuxExternal                    // external diagnosis
	VDevAuxSplitPool                   // vdev was split off into another pool
)