freebsd-nq/include/sys/zfs_ioctl.h
Serapheim Dimitropoulos 8d103d8856 OpenZFS 8604 - Simplify snapshots unmounting code
Authored by: Serapheim Dimitropoulos <serapheim@delphix.com>
Reviewed by: Matt Ahrens <mahrens@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Andy Stormont <astormont@racktopsystems.com>
Approved by: Robert Mustacchi <rm@joyent.com>
Ported-by: Don Brady <don.brady@delphix.com>

Every time we want to unmount a snapshot (happens during snapshot
deletion or renaming) we unnecessarily iterate through all the
mountpoints in the VFS layer (see zfs_get_vfs).

The current patch completely gets rid of that code and changes
the approach while keeping the behavior of that code path the
same. Specifically, it puts a hold on the dataset/snapshot and
gets its vfs resource reference directly, instead of linearly
searching for it. If that reference exists we attempt to amount
it.

With the above change, it became obvious that the nvlist
manipulations that we do (add_boolean and add_nvlist) take a
significant amount of time ensuring uniqueness of every new
element even though they don't have too. Thus, we updated the
patch so those nvlists are not trying to enforce the uniqueness
of their elements.

A more complete analysis of the problem solved by this patch
can be found below:
https://sdimitro.github.io/post/snap-unmount-perf/

OpenZFS-issue: https://www.illumos.org/issues/8604
OpenZFS-commit: https://github.com/openzfs/openzfs/commit/126118fb
2018-02-08 15:29:44 -08:00

525 lines
15 KiB
C

/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
* Copyright (c) 2012, 2017 by Delphix. All rights reserved.
* Copyright 2016 RackTop Systems.
* Copyright (c) 2017, Intel Corporation.
*/
#ifndef _SYS_ZFS_IOCTL_H
#define _SYS_ZFS_IOCTL_H
#include <sys/cred.h>
#include <sys/dmu.h>
#include <sys/zio.h>
#include <sys/dsl_deleg.h>
#include <sys/spa.h>
#include <sys/zfs_stat.h>
#ifdef _KERNEL
#include <sys/nvpair.h>
#endif /* _KERNEL */
#ifdef __cplusplus
extern "C" {
#endif
/*
* The structures in this file are passed between userland and the
* kernel. Userland may be running a 32-bit process, while the kernel
* is 64-bit. Therefore, these structures need to compile the same in
* 32-bit and 64-bit. This means not using type "long", and adding
* explicit padding so that the 32-bit structure will not be packed more
* tightly than the 64-bit structure (which requires 64-bit alignment).
*/
/*
* Property values for snapdir
*/
#define ZFS_SNAPDIR_HIDDEN 0
#define ZFS_SNAPDIR_VISIBLE 1
/*
* Property values for snapdev
*/
#define ZFS_SNAPDEV_HIDDEN 0
#define ZFS_SNAPDEV_VISIBLE 1
/*
* Property values for acltype
*/
#define ZFS_ACLTYPE_OFF 0
#define ZFS_ACLTYPE_POSIXACL 1
/*
* Field manipulation macros for the drr_versioninfo field of the
* send stream header.
*/
/*
* Header types for zfs send streams.
*/
typedef enum drr_headertype {
DMU_SUBSTREAM = 0x1,
DMU_COMPOUNDSTREAM = 0x2
} drr_headertype_t;
#define DMU_GET_STREAM_HDRTYPE(vi) BF64_GET((vi), 0, 2)
#define DMU_SET_STREAM_HDRTYPE(vi, x) BF64_SET((vi), 0, 2, x)
#define DMU_GET_FEATUREFLAGS(vi) BF64_GET((vi), 2, 30)
#define DMU_SET_FEATUREFLAGS(vi, x) BF64_SET((vi), 2, 30, x)
/*
* Feature flags for zfs send streams (flags in drr_versioninfo)
*/
#define DMU_BACKUP_FEATURE_DEDUP (1 << 0)
#define DMU_BACKUP_FEATURE_DEDUPPROPS (1 << 1)
#define DMU_BACKUP_FEATURE_SA_SPILL (1 << 2)
/* flags #3 - #15 are reserved for incompatible closed-source implementations */
#define DMU_BACKUP_FEATURE_EMBED_DATA (1 << 16)
#define DMU_BACKUP_FEATURE_LZ4 (1 << 17)
/* flag #18 is reserved for a Delphix feature */
#define DMU_BACKUP_FEATURE_LARGE_BLOCKS (1 << 19)
#define DMU_BACKUP_FEATURE_RESUMING (1 << 20)
/* flag #21 is reserved for a Delphix feature */
#define DMU_BACKUP_FEATURE_COMPRESSED (1 << 22)
#define DMU_BACKUP_FEATURE_LARGE_DNODE (1 << 23)
#define DMU_BACKUP_FEATURE_RAW (1 << 24)
/*
* Mask of all supported backup features
*/
#define DMU_BACKUP_FEATURE_MASK (DMU_BACKUP_FEATURE_DEDUP | \
DMU_BACKUP_FEATURE_DEDUPPROPS | DMU_BACKUP_FEATURE_SA_SPILL | \
DMU_BACKUP_FEATURE_EMBED_DATA | DMU_BACKUP_FEATURE_LZ4 | \
DMU_BACKUP_FEATURE_RESUMING | DMU_BACKUP_FEATURE_LARGE_BLOCKS | \
DMU_BACKUP_FEATURE_COMPRESSED | DMU_BACKUP_FEATURE_LARGE_DNODE | \
DMU_BACKUP_FEATURE_RAW)
/* Are all features in the given flag word currently supported? */
#define DMU_STREAM_SUPPORTED(x) (!((x) & ~DMU_BACKUP_FEATURE_MASK))
typedef enum dmu_send_resume_token_version {
ZFS_SEND_RESUME_TOKEN_VERSION = 1
} dmu_send_resume_token_version_t;
/*
* The drr_versioninfo field of the dmu_replay_record has the
* following layout:
*
* 64 56 48 40 32 24 16 8 0
* +-------+-------+-------+-------+-------+-------+-------+-------+
* | reserved | feature-flags |C|S|
* +-------+-------+-------+-------+-------+-------+-------+-------+
*
* The low order two bits indicate the header type: SUBSTREAM (0x1)
* or COMPOUNDSTREAM (0x2). Using two bits for this is historical:
* this field used to be a version number, where the two version types
* were 1 and 2. Using two bits for this allows earlier versions of
* the code to be able to recognize send streams that don't use any
* of the features indicated by feature flags.
*/
#define DMU_BACKUP_MAGIC 0x2F5bacbacULL
/*
* Send stream flags. Bits 24-31 are reserved for vendor-specific
* implementations and should not be used.
*/
#define DRR_FLAG_CLONE (1<<0)
#define DRR_FLAG_CI_DATA (1<<1)
/*
* This send stream, if it is a full send, includes the FREE and FREEOBJECT
* records that are created by the sending process. This means that the send
* stream can be received as a clone, even though it is not an incremental.
* This is not implemented as a feature flag, because the receiving side does
* not need to have implemented it to receive this stream; it is fully backwards
* compatible. We need a flag, though, because full send streams without it
* cannot necessarily be received as a clone correctly.
*/
#define DRR_FLAG_FREERECORDS (1<<2)
/*
* flags in the drr_flags field in the DRR_WRITE, DRR_SPILL, DRR_OBJECT,
* DRR_WRITE_BYREF, and DRR_OBJECT_RANGE blocks
*/
#define DRR_CHECKSUM_DEDUP (1<<0) /* not used for DRR_SPILL blocks */
#define DRR_RAW_BYTESWAP (1<<1)
#define DRR_IS_DEDUP_CAPABLE(flags) ((flags) & DRR_CHECKSUM_DEDUP)
#define DRR_IS_RAW_BYTESWAPPED(flags) ((flags) & DRR_RAW_BYTESWAP)
/* deal with compressed drr_write replay records */
#define DRR_WRITE_COMPRESSED(drrw) ((drrw)->drr_compressiontype != 0)
#define DRR_WRITE_PAYLOAD_SIZE(drrw) \
(DRR_WRITE_COMPRESSED(drrw) ? (drrw)->drr_compressed_size : \
(drrw)->drr_logical_size)
#define DRR_SPILL_PAYLOAD_SIZE(drrs) \
((drrs)->drr_compressed_size ? \
(drrs)->drr_compressed_size : (drrs)->drr_length)
#define DRR_OBJECT_PAYLOAD_SIZE(drro) \
((drro)->drr_raw_bonuslen != 0 ? \
(drro)->drr_raw_bonuslen : P2ROUNDUP((drro)->drr_bonuslen, 8))
/*
* zfs ioctl command structure
*/
typedef struct dmu_replay_record {
enum {
DRR_BEGIN, DRR_OBJECT, DRR_FREEOBJECTS,
DRR_WRITE, DRR_FREE, DRR_END, DRR_WRITE_BYREF,
DRR_SPILL, DRR_WRITE_EMBEDDED, DRR_OBJECT_RANGE,
DRR_NUMTYPES
} drr_type;
uint32_t drr_payloadlen;
union {
struct drr_begin {
uint64_t drr_magic;
uint64_t drr_versioninfo; /* was drr_version */
uint64_t drr_creation_time;
dmu_objset_type_t drr_type;
uint32_t drr_flags;
uint64_t drr_toguid;
uint64_t drr_fromguid;
char drr_toname[MAXNAMELEN];
} drr_begin;
struct drr_end {
zio_cksum_t drr_checksum;
uint64_t drr_toguid;
} drr_end;
struct drr_object {
uint64_t drr_object;
dmu_object_type_t drr_type;
dmu_object_type_t drr_bonustype;
uint32_t drr_blksz;
uint32_t drr_bonuslen;
uint8_t drr_checksumtype;
uint8_t drr_compress;
uint8_t drr_dn_slots;
uint8_t drr_flags;
uint32_t drr_raw_bonuslen;
uint64_t drr_toguid;
/* only (possibly) nonzero for raw streams */
uint8_t drr_indblkshift;
uint8_t drr_nlevels;
uint8_t drr_nblkptr;
uint8_t drr_pad[5];
uint64_t drr_maxblkid;
/* bonus content follows */
} drr_object;
struct drr_freeobjects {
uint64_t drr_firstobj;
uint64_t drr_numobjs;
uint64_t drr_toguid;
} drr_freeobjects;
struct drr_write {
uint64_t drr_object;
dmu_object_type_t drr_type;
uint32_t drr_pad;
uint64_t drr_offset;
uint64_t drr_logical_size;
uint64_t drr_toguid;
uint8_t drr_checksumtype;
uint8_t drr_flags;
uint8_t drr_compressiontype;
uint8_t drr_pad2[5];
/* deduplication key */
ddt_key_t drr_key;
/* only nonzero if drr_compressiontype is not 0 */
uint64_t drr_compressed_size;
/* only nonzero for raw streams */
uint8_t drr_salt[ZIO_DATA_SALT_LEN];
uint8_t drr_iv[ZIO_DATA_IV_LEN];
uint8_t drr_mac[ZIO_DATA_MAC_LEN];
/* content follows */
} drr_write;
struct drr_free {
uint64_t drr_object;
uint64_t drr_offset;
uint64_t drr_length;
uint64_t drr_toguid;
} drr_free;
struct drr_write_byref {
/* where to put the data */
uint64_t drr_object;
uint64_t drr_offset;
uint64_t drr_length;
uint64_t drr_toguid;
/* where to find the prior copy of the data */
uint64_t drr_refguid;
uint64_t drr_refobject;
uint64_t drr_refoffset;
/* properties of the data */
uint8_t drr_checksumtype;
uint8_t drr_flags;
uint8_t drr_pad2[6];
ddt_key_t drr_key; /* deduplication key */
} drr_write_byref;
struct drr_spill {
uint64_t drr_object;
uint64_t drr_length;
uint64_t drr_toguid;
uint8_t drr_flags;
uint8_t drr_compressiontype;
uint8_t drr_pad[6];
/* only nonzero for raw streams */
uint64_t drr_compressed_size;
uint8_t drr_salt[ZIO_DATA_SALT_LEN];
uint8_t drr_iv[ZIO_DATA_IV_LEN];
uint8_t drr_mac[ZIO_DATA_MAC_LEN];
dmu_object_type_t drr_type;
/* spill data follows */
} drr_spill;
struct drr_write_embedded {
uint64_t drr_object;
uint64_t drr_offset;
/* logical length, should equal blocksize */
uint64_t drr_length;
uint64_t drr_toguid;
uint8_t drr_compression;
uint8_t drr_etype;
uint8_t drr_pad[6];
uint32_t drr_lsize; /* uncompressed size of payload */
uint32_t drr_psize; /* compr. (real) size of payload */
/* (possibly compressed) content follows */
} drr_write_embedded;
struct drr_object_range {
uint64_t drr_firstobj;
uint64_t drr_numslots;
uint64_t drr_toguid;
uint8_t drr_salt[ZIO_DATA_SALT_LEN];
uint8_t drr_iv[ZIO_DATA_IV_LEN];
uint8_t drr_mac[ZIO_DATA_MAC_LEN];
uint8_t drr_flags;
uint8_t drr_pad[3];
} drr_object_range;
/*
* Nore: drr_checksum is overlaid with all record types
* except DRR_BEGIN. Therefore its (non-pad) members
* must not overlap with members from the other structs.
* We accomplish this by putting its members at the very
* end of the struct.
*/
struct drr_checksum {
uint64_t drr_pad[34];
/*
* fletcher-4 checksum of everything preceding the
* checksum.
*/
zio_cksum_t drr_checksum;
} drr_checksum;
} drr_u;
} dmu_replay_record_t;
/* diff record range types */
typedef enum diff_type {
DDR_NONE = 0x1,
DDR_INUSE = 0x2,
DDR_FREE = 0x4
} diff_type_t;
/*
* The diff reports back ranges of free or in-use objects.
*/
typedef struct dmu_diff_record {
uint64_t ddr_type;
uint64_t ddr_first;
uint64_t ddr_last;
} dmu_diff_record_t;
typedef struct zinject_record {
uint64_t zi_objset;
uint64_t zi_object;
uint64_t zi_start;
uint64_t zi_end;
uint64_t zi_guid;
uint32_t zi_level;
uint32_t zi_error;
uint64_t zi_type;
uint32_t zi_freq;
uint32_t zi_failfast;
char zi_func[MAXNAMELEN];
uint32_t zi_iotype;
int32_t zi_duration;
uint64_t zi_timer;
uint64_t zi_nlanes;
uint32_t zi_cmd;
uint32_t zi_pad;
} zinject_record_t;
#define ZINJECT_NULL 0x1
#define ZINJECT_FLUSH_ARC 0x2
#define ZINJECT_UNLOAD_SPA 0x4
#define ZEVENT_NONE 0x0
#define ZEVENT_NONBLOCK 0x1
#define ZEVENT_SIZE 1024
#define ZEVENT_SEEK_START 0
#define ZEVENT_SEEK_END UINT64_MAX
/* scaled frequency ranges */
#define ZI_PERCENTAGE_MIN 4294UL
#define ZI_PERCENTAGE_MAX UINT32_MAX
typedef enum zinject_type {
ZINJECT_UNINITIALIZED,
ZINJECT_DATA_FAULT,
ZINJECT_DEVICE_FAULT,
ZINJECT_LABEL_FAULT,
ZINJECT_IGNORED_WRITES,
ZINJECT_PANIC,
ZINJECT_DELAY_IO,
} zinject_type_t;
typedef struct zfs_share {
uint64_t z_exportdata;
uint64_t z_sharedata;
uint64_t z_sharetype; /* 0 = share, 1 = unshare */
uint64_t z_sharemax; /* max length of share string */
} zfs_share_t;
/*
* ZFS file systems may behave the usual, POSIX-compliant way, where
* name lookups are case-sensitive. They may also be set up so that
* all the name lookups are case-insensitive, or so that only some
* lookups, the ones that set an FIGNORECASE flag, are case-insensitive.
*/
typedef enum zfs_case {
ZFS_CASE_SENSITIVE,
ZFS_CASE_INSENSITIVE,
ZFS_CASE_MIXED
} zfs_case_t;
/*
* Note: this struct must have the same layout in 32-bit and 64-bit, so
* that 32-bit processes (like /sbin/zfs) can pass it to the 64-bit
* kernel. Therefore, we add padding to it so that no "hidden" padding
* is automatically added on 64-bit (but not on 32-bit).
*/
typedef struct zfs_cmd {
char zc_name[MAXPATHLEN]; /* name of pool or dataset */
uint64_t zc_nvlist_src; /* really (char *) */
uint64_t zc_nvlist_src_size;
uint64_t zc_nvlist_dst; /* really (char *) */
uint64_t zc_nvlist_dst_size;
boolean_t zc_nvlist_dst_filled; /* put an nvlist in dst? */
int zc_pad2;
/*
* The following members are for legacy ioctls which haven't been
* converted to the new method.
*/
uint64_t zc_history; /* really (char *) */
char zc_value[MAXPATHLEN * 2];
char zc_string[MAXNAMELEN];
uint64_t zc_guid;
uint64_t zc_nvlist_conf; /* really (char *) */
uint64_t zc_nvlist_conf_size;
uint64_t zc_cookie;
uint64_t zc_objset_type;
uint64_t zc_perm_action;
uint64_t zc_history_len;
uint64_t zc_history_offset;
uint64_t zc_obj;
uint64_t zc_iflags; /* internal to zfs(7fs) */
zfs_share_t zc_share;
dmu_objset_stats_t zc_objset_stats;
struct drr_begin zc_begin_record;
zinject_record_t zc_inject_record;
uint32_t zc_defer_destroy;
uint32_t zc_flags;
uint64_t zc_action_handle;
int zc_cleanup_fd;
uint8_t zc_simple;
uint8_t zc_pad[3]; /* alignment */
uint64_t zc_sendobj;
uint64_t zc_fromobj;
uint64_t zc_createtxg;
zfs_stat_t zc_stat;
} zfs_cmd_t;
typedef struct zfs_useracct {
char zu_domain[256];
uid_t zu_rid;
uint32_t zu_pad;
uint64_t zu_space;
} zfs_useracct_t;
#define ZFSDEV_MAX_MINOR (1 << 16)
#define ZFS_MIN_MINOR (ZFSDEV_MAX_MINOR + 1)
#define ZPOOL_EXPORT_AFTER_SPLIT 0x1
#ifdef _KERNEL
struct objset;
struct zfsvfs;
typedef struct zfs_creat {
nvlist_t *zct_zplprops;
nvlist_t *zct_props;
} zfs_creat_t;
extern int zfs_secpolicy_snapshot_perms(const char *, cred_t *);
extern int zfs_secpolicy_rename_perms(const char *, const char *, cred_t *);
extern int zfs_secpolicy_destroy_perms(const char *, cred_t *);
extern void zfs_unmount_snap(const char *);
extern void zfs_destroy_unmount_origin(const char *);
extern boolean_t dataset_name_hidden(const char *);
extern int getzfsvfs_impl(struct objset *, struct zfsvfs **);
extern int getzfsvfs(const char *, struct zfsvfs **);
enum zfsdev_state_type {
ZST_ONEXIT,
ZST_ZEVENT,
ZST_ALL,
};
/*
* The zfsdev_state_t structure is managed as a singly-linked list
* from which items are never deleted. This allows for lock-free
* reading of the list so long as assignments to the zs_next and
* reads from zs_minor are performed atomically. Empty items are
* indicated by storing -1 into zs_minor.
*/
typedef struct zfsdev_state {
struct zfsdev_state *zs_next; /* next zfsdev_state_t link */
struct file *zs_file; /* associated file struct */
minor_t zs_minor; /* made up minor number */
void *zs_onexit; /* onexit data */
void *zs_zevent; /* zevent data */
} zfsdev_state_t;
extern void *zfsdev_get_state(minor_t minor, enum zfsdev_state_type which);
extern int zfsdev_getminor(struct file *filp, minor_t *minorp);
extern minor_t zfsdev_minor_alloc(void);
#endif /* _KERNEL */
#ifdef __cplusplus
}
#endif
#endif /* _SYS_ZFS_IOCTL_H */