freebsd-nq/include/sys/vdev_impl.h
Serapheim Dimitropoulos 93e28d661e Log Spacemap Project
= Motivation

At Delphix we've seen a lot of customer systems where fragmentation
is over 75% and random writes take a performance hit because a lot
of time is spend on I/Os that update on-disk space accounting metadata.
Specifically, we seen cases where 20% to 40% of sync time is spend
after sync pass 1 and ~30% of the I/Os on the system is spent updating
spacemaps.

The problem is that these pools have existed long enough that we've
touched almost every metaslab at least once, and random writes
scatter frees across all metaslabs every TXG, thus appending to
their spacemaps and resulting in many I/Os. To give an example,
assuming that every VDEV has 200 metaslabs and our writes fit within
a single spacemap block (generally 4K) we have 200 I/Os. Then if we
assume 2 levels of indirection, we need 400 additional I/Os and
since we are talking about metadata for which we keep 2 extra copies
for redundancy we need to triple that number, leading to a total of
1800 I/Os per VDEV every TXG.

We could try and decrease the number of metaslabs so we have less
I/Os per TXG but then each metaslab would cover a wider range on
disk and thus would take more time to be loaded in memory from disk.
In addition, after it's loaded, it's range tree would consume more
memory.

Another idea would be to just increase the spacemap block size
which would allow us to fit more entries within an I/O block
resulting in fewer I/Os per metaslab and a speedup in loading time.
The problem is still that we don't deal with the number of I/Os
going up as the number of metaslabs is increasing and the fact
is that we generally write a lot to a few metaslabs and a little
to the rest of them. Thus, just increasing the block size would
actually waste bandwidth because we won't be utilizing our bigger
block size.

= About this patch

This patch introduces the Log Spacemap project which provides the
solution to the above problem while taking into account all the
aforementioned tradeoffs. The details on how it achieves that can
be found in the references sections below and in the code (see
Big Theory Statement in spa_log_spacemap.c).

Even though the change is fairly constraint within the metaslab
and lower-level SPA codepaths, there is a side-change that is
user-facing. The change is that VDEV IDs from VDEV holes will no
longer be reused. To give some background and reasoning for this,
when a log device is removed and its VDEV structure was replaced
with a hole (or was compacted; if at the end of the vdev array),
its vdev_id could be reused by devices added after that. Now
with the pool-wide space maps recording the vdev ID, this behavior
can cause problems (e.g. is this entry referring to a segment in
the new vdev or the removed log?). Thus, to simplify things the
ID reuse behavior is gone and now vdev IDs for top-level vdevs
are truly unique within a pool.

= Testing

The illumos implementation of this feature has been used internally
for a year and has been in production for ~6 months. For this patch
specifically there don't seem to be any regressions introduced to
ZTS and I have been running zloop for a week without any related
problems.

= Performance Analysis (Linux Specific)

All performance results and analysis for illumos can be found in
the links of the references. Redoing the same experiments in Linux
gave similar results. Below are the specifics of the Linux run.

After the pool reached stable state the percentage of the time
spent in pass 1 per TXG was 64% on average for the stock bits
while the log spacemap bits stayed at 95% during the experiment
(graph: sdimitro.github.io/img/linux-lsm/PercOfSyncInPassOne.png).

Sync times per TXG were 37.6 seconds on average for the stock
bits and 22.7 seconds for the log spacemap bits (related graph:
sdimitro.github.io/img/linux-lsm/SyncTimePerTXG.png). As a result
the log spacemap bits were able to push more TXGs, which is also
the reason why all graphs quantified per TXG have more entries for
the log spacemap bits.

Another interesting aspect in terms of txg syncs is that the stock
bits had 22% of their TXGs reach sync pass 7, 55% reach sync pass 8,
and 20% reach 9. The log space map bits reached sync pass 4 in 79%
of their TXGs, sync pass 7 in 19%, and sync pass 8 at 1%. This
emphasizes the fact that not only we spend less time on metadata
but we also iterate less times to convergence in spa_sync() dirtying
objects.
[related graphs:
stock- sdimitro.github.io/img/linux-lsm/NumberOfPassesPerTXGStock.png
lsm- sdimitro.github.io/img/linux-lsm/NumberOfPassesPerTXGLSM.png]

Finally, the improvement in IOPs that the userland gains from the
change is approximately 40%. There is a consistent win in IOPS as
you can see from the graphs below but the absolute amount of
improvement that the log spacemap gives varies within each minute
interval.
sdimitro.github.io/img/linux-lsm/StockVsLog3Days.png
sdimitro.github.io/img/linux-lsm/StockVsLog10Hours.png

= Porting to Other Platforms

For people that want to port this commit to other platforms below
is a list of ZoL commits that this patch depends on:

Make zdb results for checkpoint tests consistent
db587941c5

Update vdev_is_spacemap_addressable() for new spacemap encoding
419ba59145

Simplify spa_sync by breaking it up to smaller functions
8dc2197b7b

Factor metaslab_load_wait() in metaslab_load()
b194fab0fb

Rename range_tree_verify to range_tree_verify_not_present
df72b8bebe

Change target size of metaslabs from 256GB to 16GB
c853f382db

zdb -L should skip leak detection altogether
21e7cf5da8

vs_alloc can underflow in L2ARC vdevs
7558997d2f

Simplify log vdev removal code
6c926f426a

Get rid of space_map_update() for ms_synced_length
425d3237ee

Introduce auxiliary metaslab histograms
928e8ad47d

Error path in metaslab_load_impl() forgets to drop ms_sync_lock
8eef997679

= References

Background, Motivation, and Internals of the Feature
- OpenZFS 2017 Presentation:
youtu.be/jj2IxRkl5bQ
- Slides:
slideshare.net/SerapheimNikolaosDim/zfs-log-spacemaps-project

Flushing Algorithm Internals & Performance Results
(Illumos Specific)
- Blogpost:
sdimitro.github.io/post/zfs-lsm-flushing/
- OpenZFS 2018 Presentation:
youtu.be/x6D2dHRjkxw
- Slides:
slideshare.net/SerapheimNikolaosDim/zfs-log-spacemap-flushing-algorithm

Upstream Delphix Issues:
DLPX-51539, DLPX-59659, DLPX-57783, DLPX-61438, DLPX-41227, DLPX-59320
DLPX-63385

Reviewed-by: Sean Eric Fagan <sef@ixsystems.com>
Reviewed-by: Matt Ahrens <matt@delphix.com>
Reviewed-by: George Wilson <gwilson@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Serapheim Dimitropoulos <serapheim@delphix.com>
Closes #8442
2019-07-16 10:11:49 -07:00

561 lines
19 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) 2011, 2019 by Delphix. All rights reserved.
* Copyright (c) 2017, Intel Corporation.
*/
#ifndef _SYS_VDEV_IMPL_H
#define _SYS_VDEV_IMPL_H
#include <sys/avl.h>
#include <sys/bpobj.h>
#include <sys/dmu.h>
#include <sys/metaslab.h>
#include <sys/nvpair.h>
#include <sys/space_map.h>
#include <sys/vdev.h>
#include <sys/dkio.h>
#include <sys/uberblock_impl.h>
#include <sys/vdev_indirect_mapping.h>
#include <sys/vdev_indirect_births.h>
#include <sys/vdev_removal.h>
#include <sys/zfs_ratelimit.h>
#ifdef __cplusplus
extern "C" {
#endif
/*
* Virtual device descriptors.
*
* All storage pool operations go through the virtual device framework,
* which provides data replication and I/O scheduling.
*/
/*
* Forward declarations that lots of things need.
*/
typedef struct vdev_queue vdev_queue_t;
typedef struct vdev_cache vdev_cache_t;
typedef struct vdev_cache_entry vdev_cache_entry_t;
struct abd;
extern int zfs_vdev_queue_depth_pct;
extern int zfs_vdev_def_queue_depth;
extern uint32_t zfs_vdev_async_write_max_active;
/*
* Virtual device operations
*/
typedef int vdev_open_func_t(vdev_t *vd, uint64_t *size, uint64_t *max_size,
uint64_t *ashift);
typedef void vdev_close_func_t(vdev_t *vd);
typedef uint64_t vdev_asize_func_t(vdev_t *vd, uint64_t psize);
typedef void vdev_io_start_func_t(zio_t *zio);
typedef void vdev_io_done_func_t(zio_t *zio);
typedef void vdev_state_change_func_t(vdev_t *vd, int, int);
typedef boolean_t vdev_need_resilver_func_t(vdev_t *vd, uint64_t, size_t);
typedef void vdev_hold_func_t(vdev_t *vd);
typedef void vdev_rele_func_t(vdev_t *vd);
typedef void vdev_remap_cb_t(uint64_t inner_offset, vdev_t *vd,
uint64_t offset, uint64_t size, void *arg);
typedef void vdev_remap_func_t(vdev_t *vd, uint64_t offset, uint64_t size,
vdev_remap_cb_t callback, void *arg);
/*
* Given a target vdev, translates the logical range "in" to the physical
* range "res"
*/
typedef void vdev_xlation_func_t(vdev_t *cvd, const range_seg_t *in,
range_seg_t *res);
typedef const struct vdev_ops {
vdev_open_func_t *vdev_op_open;
vdev_close_func_t *vdev_op_close;
vdev_asize_func_t *vdev_op_asize;
vdev_io_start_func_t *vdev_op_io_start;
vdev_io_done_func_t *vdev_op_io_done;
vdev_state_change_func_t *vdev_op_state_change;
vdev_need_resilver_func_t *vdev_op_need_resilver;
vdev_hold_func_t *vdev_op_hold;
vdev_rele_func_t *vdev_op_rele;
vdev_remap_func_t *vdev_op_remap;
/*
* For translating ranges from non-leaf vdevs (e.g. raidz) to leaves.
* Used when initializing vdevs. Isn't used by leaf ops.
*/
vdev_xlation_func_t *vdev_op_xlate;
char vdev_op_type[16];
boolean_t vdev_op_leaf;
} vdev_ops_t;
/*
* Virtual device properties
*/
struct vdev_cache_entry {
struct abd *ve_abd;
uint64_t ve_offset;
clock_t ve_lastused;
avl_node_t ve_offset_node;
avl_node_t ve_lastused_node;
uint32_t ve_hits;
uint16_t ve_missed_update;
zio_t *ve_fill_io;
};
struct vdev_cache {
avl_tree_t vc_offset_tree;
avl_tree_t vc_lastused_tree;
kmutex_t vc_lock;
};
typedef struct vdev_queue_class {
uint32_t vqc_active;
/*
* Sorted by offset or timestamp, depending on if the queue is
* LBA-ordered vs FIFO.
*/
avl_tree_t vqc_queued_tree;
} vdev_queue_class_t;
struct vdev_queue {
vdev_t *vq_vdev;
vdev_queue_class_t vq_class[ZIO_PRIORITY_NUM_QUEUEABLE];
avl_tree_t vq_active_tree;
avl_tree_t vq_read_offset_tree;
avl_tree_t vq_write_offset_tree;
avl_tree_t vq_trim_offset_tree;
uint64_t vq_last_offset;
hrtime_t vq_io_complete_ts; /* time last i/o completed */
hrtime_t vq_io_delta_ts;
zio_t vq_io_search; /* used as local for stack reduction */
kmutex_t vq_lock;
};
typedef enum vdev_alloc_bias {
VDEV_BIAS_NONE,
VDEV_BIAS_LOG, /* dedicated to ZIL data (SLOG) */
VDEV_BIAS_SPECIAL, /* dedicated to ddt, metadata, and small blks */
VDEV_BIAS_DEDUP /* dedicated to dedup metadata */
} vdev_alloc_bias_t;
/*
* On-disk indirect vdev state.
*
* An indirect vdev is described exclusively in the MOS config of a pool.
* The config for an indirect vdev includes several fields, which are
* accessed in memory by a vdev_indirect_config_t.
*/
typedef struct vdev_indirect_config {
/*
* Object (in MOS) which contains the indirect mapping. This object
* contains an array of vdev_indirect_mapping_entry_phys_t ordered by
* vimep_src. The bonus buffer for this object is a
* vdev_indirect_mapping_phys_t. This object is allocated when a vdev
* removal is initiated.
*
* Note that this object can be empty if none of the data on the vdev
* has been copied yet.
*/
uint64_t vic_mapping_object;
/*
* Object (in MOS) which contains the birth times for the mapping
* entries. This object contains an array of
* vdev_indirect_birth_entry_phys_t sorted by vibe_offset. The bonus
* buffer for this object is a vdev_indirect_birth_phys_t. This object
* is allocated when a vdev removal is initiated.
*
* Note that this object can be empty if none of the vdev has yet been
* copied.
*/
uint64_t vic_births_object;
/*
* This is the vdev ID which was removed previous to this vdev, or
* UINT64_MAX if there are no previously removed vdevs.
*/
uint64_t vic_prev_indirect_vdev;
} vdev_indirect_config_t;
/*
* Virtual device descriptor
*/
struct vdev {
/*
* Common to all vdev types.
*/
uint64_t vdev_id; /* child number in vdev parent */
uint64_t vdev_guid; /* unique ID for this vdev */
uint64_t vdev_guid_sum; /* self guid + all child guids */
uint64_t vdev_orig_guid; /* orig. guid prior to remove */
uint64_t vdev_asize; /* allocatable device capacity */
uint64_t vdev_min_asize; /* min acceptable asize */
uint64_t vdev_max_asize; /* max acceptable asize */
uint64_t vdev_ashift; /* block alignment shift */
uint64_t vdev_state; /* see VDEV_STATE_* #defines */
uint64_t vdev_prevstate; /* used when reopening a vdev */
vdev_ops_t *vdev_ops; /* vdev operations */
spa_t *vdev_spa; /* spa for this vdev */
void *vdev_tsd; /* type-specific data */
vnode_t *vdev_name_vp; /* vnode for pathname */
vnode_t *vdev_devid_vp; /* vnode for devid */
vdev_t *vdev_top; /* top-level vdev */
vdev_t *vdev_parent; /* parent vdev */
vdev_t **vdev_child; /* array of children */
uint64_t vdev_children; /* number of children */
vdev_stat_t vdev_stat; /* virtual device statistics */
vdev_stat_ex_t vdev_stat_ex; /* extended statistics */
boolean_t vdev_expanding; /* expand the vdev? */
boolean_t vdev_reopening; /* reopen in progress? */
boolean_t vdev_nonrot; /* true if solid state */
int vdev_open_error; /* error on last open */
kthread_t *vdev_open_thread; /* thread opening children */
uint64_t vdev_crtxg; /* txg when top-level was added */
/*
* Top-level vdev state.
*/
uint64_t vdev_ms_array; /* metaslab array object */
uint64_t vdev_ms_shift; /* metaslab size shift */
uint64_t vdev_ms_count; /* number of metaslabs */
metaslab_group_t *vdev_mg; /* metaslab group */
metaslab_t **vdev_ms; /* metaslab array */
uint64_t vdev_pending_fastwrite; /* allocated fastwrites */
txg_list_t vdev_ms_list; /* per-txg dirty metaslab lists */
txg_list_t vdev_dtl_list; /* per-txg dirty DTL lists */
txg_node_t vdev_txg_node; /* per-txg dirty vdev linkage */
boolean_t vdev_remove_wanted; /* async remove wanted? */
boolean_t vdev_probe_wanted; /* async probe wanted? */
list_node_t vdev_config_dirty_node; /* config dirty list */
list_node_t vdev_state_dirty_node; /* state dirty list */
uint64_t vdev_deflate_ratio; /* deflation ratio (x512) */
uint64_t vdev_islog; /* is an intent log device */
uint64_t vdev_removing; /* device is being removed? */
boolean_t vdev_ishole; /* is a hole in the namespace */
uint64_t vdev_top_zap;
vdev_alloc_bias_t vdev_alloc_bias; /* metaslab allocation bias */
/* pool checkpoint related */
space_map_t *vdev_checkpoint_sm; /* contains reserved blocks */
/* Initialize related */
boolean_t vdev_initialize_exit_wanted;
vdev_initializing_state_t vdev_initialize_state;
list_node_t vdev_initialize_node;
kthread_t *vdev_initialize_thread;
/* Protects vdev_initialize_thread and vdev_initialize_state. */
kmutex_t vdev_initialize_lock;
kcondvar_t vdev_initialize_cv;
uint64_t vdev_initialize_offset[TXG_SIZE];
uint64_t vdev_initialize_last_offset;
range_tree_t *vdev_initialize_tree; /* valid while initializing */
uint64_t vdev_initialize_bytes_est;
uint64_t vdev_initialize_bytes_done;
time_t vdev_initialize_action_time; /* start and end time */
/* TRIM related */
boolean_t vdev_trim_exit_wanted;
boolean_t vdev_autotrim_exit_wanted;
vdev_trim_state_t vdev_trim_state;
list_node_t vdev_trim_node;
kmutex_t vdev_autotrim_lock;
kcondvar_t vdev_autotrim_cv;
kthread_t *vdev_autotrim_thread;
/* Protects vdev_trim_thread and vdev_trim_state. */
kmutex_t vdev_trim_lock;
kcondvar_t vdev_trim_cv;
kthread_t *vdev_trim_thread;
uint64_t vdev_trim_offset[TXG_SIZE];
uint64_t vdev_trim_last_offset;
uint64_t vdev_trim_bytes_est;
uint64_t vdev_trim_bytes_done;
uint64_t vdev_trim_rate; /* requested rate (bytes/sec) */
uint64_t vdev_trim_partial; /* requested partial TRIM */
uint64_t vdev_trim_secure; /* requested secure TRIM */
time_t vdev_trim_action_time; /* start and end time */
/* for limiting outstanding I/Os (initialize and TRIM) */
kmutex_t vdev_initialize_io_lock;
kcondvar_t vdev_initialize_io_cv;
uint64_t vdev_initialize_inflight;
kmutex_t vdev_trim_io_lock;
kcondvar_t vdev_trim_io_cv;
uint64_t vdev_trim_inflight[2];
/*
* Values stored in the config for an indirect or removing vdev.
*/
vdev_indirect_config_t vdev_indirect_config;
/*
* The vdev_indirect_rwlock protects the vdev_indirect_mapping
* pointer from changing on indirect vdevs (when it is condensed).
* Note that removing (not yet indirect) vdevs have different
* access patterns (the mapping is not accessed from open context,
* e.g. from zio_read) and locking strategy (e.g. svr_lock).
*/
krwlock_t vdev_indirect_rwlock;
vdev_indirect_mapping_t *vdev_indirect_mapping;
vdev_indirect_births_t *vdev_indirect_births;
/*
* In memory data structures used to manage the obsolete sm, for
* indirect or removing vdevs.
*
* The vdev_obsolete_segments is the in-core record of the segments
* that are no longer referenced anywhere in the pool (due to
* being freed or remapped and not referenced by any snapshots).
* During a sync, segments are added to vdev_obsolete_segments
* via vdev_indirect_mark_obsolete(); at the end of each sync
* pass, this is appended to vdev_obsolete_sm via
* vdev_indirect_sync_obsolete(). The vdev_obsolete_lock
* protects against concurrent modifications of vdev_obsolete_segments
* from multiple zio threads.
*/
kmutex_t vdev_obsolete_lock;
range_tree_t *vdev_obsolete_segments;
space_map_t *vdev_obsolete_sm;
/*
* Protects the vdev_scan_io_queue field itself as well as the
* structure's contents (when present).
*/
kmutex_t vdev_scan_io_queue_lock;
struct dsl_scan_io_queue *vdev_scan_io_queue;
/*
* Leaf vdev state.
*/
range_tree_t *vdev_dtl[DTL_TYPES]; /* dirty time logs */
space_map_t *vdev_dtl_sm; /* dirty time log space map */
txg_node_t vdev_dtl_node; /* per-txg dirty DTL linkage */
uint64_t vdev_dtl_object; /* DTL object */
uint64_t vdev_psize; /* physical device capacity */
uint64_t vdev_wholedisk; /* true if this is a whole disk */
uint64_t vdev_offline; /* persistent offline state */
uint64_t vdev_faulted; /* persistent faulted state */
uint64_t vdev_degraded; /* persistent degraded state */
uint64_t vdev_removed; /* persistent removed state */
uint64_t vdev_resilver_txg; /* persistent resilvering state */
uint64_t vdev_nparity; /* number of parity devices for raidz */
char *vdev_path; /* vdev path (if any) */
char *vdev_devid; /* vdev devid (if any) */
char *vdev_physpath; /* vdev device path (if any) */
char *vdev_enc_sysfs_path; /* enclosure sysfs path */
char *vdev_fru; /* physical FRU location */
uint64_t vdev_not_present; /* not present during import */
uint64_t vdev_unspare; /* unspare when resilvering done */
boolean_t vdev_nowritecache; /* true if flushwritecache failed */
boolean_t vdev_has_trim; /* TRIM is supported */
boolean_t vdev_has_securetrim; /* secure TRIM is supported */
boolean_t vdev_checkremove; /* temporary online test */
boolean_t vdev_forcefault; /* force online fault */
boolean_t vdev_splitting; /* split or repair in progress */
boolean_t vdev_delayed_close; /* delayed device close? */
boolean_t vdev_tmpoffline; /* device taken offline temporarily? */
boolean_t vdev_detached; /* device detached? */
boolean_t vdev_cant_read; /* vdev is failing all reads */
boolean_t vdev_cant_write; /* vdev is failing all writes */
boolean_t vdev_isspare; /* was a hot spare */
boolean_t vdev_isl2cache; /* was a l2cache device */
boolean_t vdev_copy_uberblocks; /* post expand copy uberblocks */
boolean_t vdev_resilver_deferred; /* resilver deferred */
vdev_queue_t vdev_queue; /* I/O deadline schedule queue */
vdev_cache_t vdev_cache; /* physical block cache */
spa_aux_vdev_t *vdev_aux; /* for l2cache and spares vdevs */
zio_t *vdev_probe_zio; /* root of current probe */
vdev_aux_t vdev_label_aux; /* on-disk aux state */
uint64_t vdev_leaf_zap;
hrtime_t vdev_mmp_pending; /* 0 if write finished */
uint64_t vdev_mmp_kstat_id; /* to find kstat entry */
uint64_t vdev_expansion_time; /* vdev's last expansion time */
list_node_t vdev_leaf_node; /* leaf vdev list */
/*
* For DTrace to work in userland (libzpool) context, these fields must
* remain at the end of the structure. DTrace will use the kernel's
* CTF definition for 'struct vdev', and since the size of a kmutex_t is
* larger in userland, the offsets for the rest of the fields would be
* incorrect.
*/
kmutex_t vdev_dtl_lock; /* vdev_dtl_{map,resilver} */
kmutex_t vdev_stat_lock; /* vdev_stat */
kmutex_t vdev_probe_lock; /* protects vdev_probe_zio */
/*
* We rate limit ZIO delay and ZIO checksum events, since they
* can flood ZED with tons of events when a drive is acting up.
*/
zfs_ratelimit_t vdev_delay_rl;
zfs_ratelimit_t vdev_checksum_rl;
};
#define VDEV_RAIDZ_MAXPARITY 3
#define VDEV_PAD_SIZE (8 << 10)
/* 2 padding areas (vl_pad1 and vl_pad2) to skip */
#define VDEV_SKIP_SIZE VDEV_PAD_SIZE * 2
#define VDEV_PHYS_SIZE (112 << 10)
#define VDEV_UBERBLOCK_RING (128 << 10)
/*
* MMP blocks occupy the last MMP_BLOCKS_PER_LABEL slots in the uberblock
* ring when MMP is enabled.
*/
#define MMP_BLOCKS_PER_LABEL 1
/* The largest uberblock we support is 8k. */
#define MAX_UBERBLOCK_SHIFT (13)
#define VDEV_UBERBLOCK_SHIFT(vd) \
MIN(MAX((vd)->vdev_top->vdev_ashift, UBERBLOCK_SHIFT), \
MAX_UBERBLOCK_SHIFT)
#define VDEV_UBERBLOCK_COUNT(vd) \
(VDEV_UBERBLOCK_RING >> VDEV_UBERBLOCK_SHIFT(vd))
#define VDEV_UBERBLOCK_OFFSET(vd, n) \
offsetof(vdev_label_t, vl_uberblock[(n) << VDEV_UBERBLOCK_SHIFT(vd)])
#define VDEV_UBERBLOCK_SIZE(vd) (1ULL << VDEV_UBERBLOCK_SHIFT(vd))
typedef struct vdev_phys {
char vp_nvlist[VDEV_PHYS_SIZE - sizeof (zio_eck_t)];
zio_eck_t vp_zbt;
} vdev_phys_t;
typedef struct vdev_label {
char vl_pad1[VDEV_PAD_SIZE]; /* 8K */
char vl_pad2[VDEV_PAD_SIZE]; /* 8K */
vdev_phys_t vl_vdev_phys; /* 112K */
char vl_uberblock[VDEV_UBERBLOCK_RING]; /* 128K */
} vdev_label_t; /* 256K total */
/*
* vdev_dirty() flags
*/
#define VDD_METASLAB 0x01
#define VDD_DTL 0x02
/* Offset of embedded boot loader region on each label */
#define VDEV_BOOT_OFFSET (2 * sizeof (vdev_label_t))
/*
* Size of embedded boot loader region on each label.
* The total size of the first two labels plus the boot area is 4MB.
*/
#define VDEV_BOOT_SIZE (7ULL << 19) /* 3.5M */
/*
* Size of label regions at the start and end of each leaf device.
*/
#define VDEV_LABEL_START_SIZE (2 * sizeof (vdev_label_t) + VDEV_BOOT_SIZE)
#define VDEV_LABEL_END_SIZE (2 * sizeof (vdev_label_t))
#define VDEV_LABELS 4
#define VDEV_BEST_LABEL VDEV_LABELS
#define VDEV_ALLOC_LOAD 0
#define VDEV_ALLOC_ADD 1
#define VDEV_ALLOC_SPARE 2
#define VDEV_ALLOC_L2CACHE 3
#define VDEV_ALLOC_ROOTPOOL 4
#define VDEV_ALLOC_SPLIT 5
#define VDEV_ALLOC_ATTACH 6
/*
* Allocate or free a vdev
*/
extern vdev_t *vdev_alloc_common(spa_t *spa, uint_t id, uint64_t guid,
vdev_ops_t *ops);
extern int vdev_alloc(spa_t *spa, vdev_t **vdp, nvlist_t *config,
vdev_t *parent, uint_t id, int alloctype);
extern void vdev_free(vdev_t *vd);
/*
* Add or remove children and parents
*/
extern void vdev_add_child(vdev_t *pvd, vdev_t *cvd);
extern void vdev_remove_child(vdev_t *pvd, vdev_t *cvd);
extern void vdev_compact_children(vdev_t *pvd);
extern vdev_t *vdev_add_parent(vdev_t *cvd, vdev_ops_t *ops);
extern void vdev_remove_parent(vdev_t *cvd);
/*
* vdev sync load and sync
*/
extern boolean_t vdev_log_state_valid(vdev_t *vd);
extern int vdev_load(vdev_t *vd);
extern int vdev_dtl_load(vdev_t *vd);
extern void vdev_sync(vdev_t *vd, uint64_t txg);
extern void vdev_sync_done(vdev_t *vd, uint64_t txg);
extern void vdev_dirty(vdev_t *vd, int flags, void *arg, uint64_t txg);
extern void vdev_dirty_leaves(vdev_t *vd, int flags, uint64_t txg);
/*
* Available vdev types.
*/
extern vdev_ops_t vdev_root_ops;
extern vdev_ops_t vdev_mirror_ops;
extern vdev_ops_t vdev_replacing_ops;
extern vdev_ops_t vdev_raidz_ops;
extern vdev_ops_t vdev_disk_ops;
extern vdev_ops_t vdev_file_ops;
extern vdev_ops_t vdev_missing_ops;
extern vdev_ops_t vdev_hole_ops;
extern vdev_ops_t vdev_spare_ops;
extern vdev_ops_t vdev_indirect_ops;
/*
* Common size functions
*/
extern void vdev_default_xlate(vdev_t *vd, const range_seg_t *in,
range_seg_t *out);
extern uint64_t vdev_default_asize(vdev_t *vd, uint64_t psize);
extern uint64_t vdev_get_min_asize(vdev_t *vd);
extern void vdev_set_min_asize(vdev_t *vd);
/*
* Global variables
*/
extern int zfs_vdev_standard_sm_blksz;
/* zdb uses this tunable, so it must be declared here to make lint happy. */
extern int zfs_vdev_cache_size;
/*
* Functions from vdev_indirect.c
*/
extern void vdev_indirect_sync_obsolete(vdev_t *vd, dmu_tx_t *tx);
extern boolean_t vdev_indirect_should_condense(vdev_t *vd);
extern void spa_condense_indirect_start_sync(vdev_t *vd, dmu_tx_t *tx);
extern int vdev_obsolete_sm_object(vdev_t *vd, uint64_t *sm_obj);
extern int vdev_obsolete_counts_are_precise(vdev_t *vd, boolean_t *are_precise);
/*
* Other miscellaneous functions
*/
int vdev_checkpoint_sm_object(vdev_t *vd, uint64_t *sm_obj);
#ifdef __cplusplus
}
#endif
#endif /* _SYS_VDEV_IMPL_H */