freebsd-dev/sys/geom/raid/tr_raid1.c

985 lines
29 KiB
C

/*-
* Copyright (c) 2010 Alexander Motin <mav@FreeBSD.org>
* 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.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, 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 DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/bio.h>
#include <sys/endian.h>
#include <sys/kernel.h>
#include <sys/kobj.h>
#include <sys/limits.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/mutex.h>
#include <sys/sysctl.h>
#include <sys/systm.h>
#include <geom/geom.h>
#include "geom/raid/g_raid.h"
#include "g_raid_tr_if.h"
SYSCTL_DECL(_kern_geom_raid_raid1);
#define RAID1_REBUILD_SLAB (1 << 20) /* One transation in a rebuild */
static int g_raid1_rebuild_slab = RAID1_REBUILD_SLAB;
SYSCTL_UINT(_kern_geom_raid_raid1, OID_AUTO, rebuild_slab_size, CTLFLAG_RWTUN,
&g_raid1_rebuild_slab, 0,
"Amount of the disk to rebuild each read/write cycle of the rebuild.");
#define RAID1_REBUILD_FAIR_IO 20 /* use 1/x of the available I/O */
static int g_raid1_rebuild_fair_io = RAID1_REBUILD_FAIR_IO;
SYSCTL_UINT(_kern_geom_raid_raid1, OID_AUTO, rebuild_fair_io, CTLFLAG_RWTUN,
&g_raid1_rebuild_fair_io, 0,
"Fraction of the I/O bandwidth to use when disk busy for rebuild.");
#define RAID1_REBUILD_CLUSTER_IDLE 100
static int g_raid1_rebuild_cluster_idle = RAID1_REBUILD_CLUSTER_IDLE;
SYSCTL_UINT(_kern_geom_raid_raid1, OID_AUTO, rebuild_cluster_idle, CTLFLAG_RWTUN,
&g_raid1_rebuild_cluster_idle, 0,
"Number of slabs to do each time we trigger a rebuild cycle");
#define RAID1_REBUILD_META_UPDATE 1024 /* update meta data every 1GB or so */
static int g_raid1_rebuild_meta_update = RAID1_REBUILD_META_UPDATE;
SYSCTL_UINT(_kern_geom_raid_raid1, OID_AUTO, rebuild_meta_update, CTLFLAG_RWTUN,
&g_raid1_rebuild_meta_update, 0,
"When to update the meta data.");
static MALLOC_DEFINE(M_TR_RAID1, "tr_raid1_data", "GEOM_RAID RAID1 data");
#define TR_RAID1_NONE 0
#define TR_RAID1_REBUILD 1
#define TR_RAID1_RESYNC 2
#define TR_RAID1_F_DOING_SOME 0x1
#define TR_RAID1_F_LOCKED 0x2
#define TR_RAID1_F_ABORT 0x4
struct g_raid_tr_raid1_object {
struct g_raid_tr_object trso_base;
int trso_starting;
int trso_stopping;
int trso_type;
int trso_recover_slabs; /* slabs before rest */
int trso_fair_io;
int trso_meta_update;
int trso_flags;
struct g_raid_subdisk *trso_failed_sd; /* like per volume */
void *trso_buffer; /* Buffer space */
struct bio trso_bio;
};
static g_raid_tr_taste_t g_raid_tr_taste_raid1;
static g_raid_tr_event_t g_raid_tr_event_raid1;
static g_raid_tr_start_t g_raid_tr_start_raid1;
static g_raid_tr_stop_t g_raid_tr_stop_raid1;
static g_raid_tr_iostart_t g_raid_tr_iostart_raid1;
static g_raid_tr_iodone_t g_raid_tr_iodone_raid1;
static g_raid_tr_kerneldump_t g_raid_tr_kerneldump_raid1;
static g_raid_tr_locked_t g_raid_tr_locked_raid1;
static g_raid_tr_idle_t g_raid_tr_idle_raid1;
static g_raid_tr_free_t g_raid_tr_free_raid1;
static kobj_method_t g_raid_tr_raid1_methods[] = {
KOBJMETHOD(g_raid_tr_taste, g_raid_tr_taste_raid1),
KOBJMETHOD(g_raid_tr_event, g_raid_tr_event_raid1),
KOBJMETHOD(g_raid_tr_start, g_raid_tr_start_raid1),
KOBJMETHOD(g_raid_tr_stop, g_raid_tr_stop_raid1),
KOBJMETHOD(g_raid_tr_iostart, g_raid_tr_iostart_raid1),
KOBJMETHOD(g_raid_tr_iodone, g_raid_tr_iodone_raid1),
KOBJMETHOD(g_raid_tr_kerneldump, g_raid_tr_kerneldump_raid1),
KOBJMETHOD(g_raid_tr_locked, g_raid_tr_locked_raid1),
KOBJMETHOD(g_raid_tr_idle, g_raid_tr_idle_raid1),
KOBJMETHOD(g_raid_tr_free, g_raid_tr_free_raid1),
{ 0, 0 }
};
static struct g_raid_tr_class g_raid_tr_raid1_class = {
"RAID1",
g_raid_tr_raid1_methods,
sizeof(struct g_raid_tr_raid1_object),
.trc_enable = 1,
.trc_priority = 100,
.trc_accept_unmapped = 1
};
static void g_raid_tr_raid1_rebuild_abort(struct g_raid_tr_object *tr);
static void g_raid_tr_raid1_maybe_rebuild(struct g_raid_tr_object *tr,
struct g_raid_subdisk *sd);
static int
g_raid_tr_taste_raid1(struct g_raid_tr_object *tr, struct g_raid_volume *vol)
{
struct g_raid_tr_raid1_object *trs;
trs = (struct g_raid_tr_raid1_object *)tr;
if (tr->tro_volume->v_raid_level != G_RAID_VOLUME_RL_RAID1 ||
(tr->tro_volume->v_raid_level_qualifier != G_RAID_VOLUME_RLQ_R1SM &&
tr->tro_volume->v_raid_level_qualifier != G_RAID_VOLUME_RLQ_R1MM))
return (G_RAID_TR_TASTE_FAIL);
trs->trso_starting = 1;
return (G_RAID_TR_TASTE_SUCCEED);
}
static int
g_raid_tr_update_state_raid1(struct g_raid_volume *vol,
struct g_raid_subdisk *sd)
{
struct g_raid_tr_raid1_object *trs;
struct g_raid_softc *sc;
struct g_raid_subdisk *tsd, *bestsd;
u_int s;
int i, na, ns;
sc = vol->v_softc;
trs = (struct g_raid_tr_raid1_object *)vol->v_tr;
if (trs->trso_stopping &&
(trs->trso_flags & TR_RAID1_F_DOING_SOME) == 0)
s = G_RAID_VOLUME_S_STOPPED;
else if (trs->trso_starting)
s = G_RAID_VOLUME_S_STARTING;
else {
/* Make sure we have at least one ACTIVE disk. */
na = g_raid_nsubdisks(vol, G_RAID_SUBDISK_S_ACTIVE);
if (na == 0) {
/*
* Critical situation! We have no any active disk!
* Choose the best disk we have to make it active.
*/
bestsd = &vol->v_subdisks[0];
for (i = 1; i < vol->v_disks_count; i++) {
tsd = &vol->v_subdisks[i];
if (tsd->sd_state > bestsd->sd_state)
bestsd = tsd;
else if (tsd->sd_state == bestsd->sd_state &&
(tsd->sd_state == G_RAID_SUBDISK_S_REBUILD ||
tsd->sd_state == G_RAID_SUBDISK_S_RESYNC) &&
tsd->sd_rebuild_pos > bestsd->sd_rebuild_pos)
bestsd = tsd;
}
if (bestsd->sd_state >= G_RAID_SUBDISK_S_UNINITIALIZED) {
/* We found reasonable candidate. */
G_RAID_DEBUG1(1, sc,
"Promote subdisk %s:%d from %s to ACTIVE.",
vol->v_name, bestsd->sd_pos,
g_raid_subdisk_state2str(bestsd->sd_state));
g_raid_change_subdisk_state(bestsd,
G_RAID_SUBDISK_S_ACTIVE);
g_raid_write_metadata(sc,
vol, bestsd, bestsd->sd_disk);
}
}
na = g_raid_nsubdisks(vol, G_RAID_SUBDISK_S_ACTIVE);
ns = g_raid_nsubdisks(vol, G_RAID_SUBDISK_S_STALE) +
g_raid_nsubdisks(vol, G_RAID_SUBDISK_S_RESYNC);
if (na == vol->v_disks_count)
s = G_RAID_VOLUME_S_OPTIMAL;
else if (na + ns == vol->v_disks_count)
s = G_RAID_VOLUME_S_SUBOPTIMAL;
else if (na > 0)
s = G_RAID_VOLUME_S_DEGRADED;
else
s = G_RAID_VOLUME_S_BROKEN;
g_raid_tr_raid1_maybe_rebuild(vol->v_tr, sd);
}
if (s != vol->v_state) {
g_raid_event_send(vol, G_RAID_VOLUME_S_ALIVE(s) ?
G_RAID_VOLUME_E_UP : G_RAID_VOLUME_E_DOWN,
G_RAID_EVENT_VOLUME);
g_raid_change_volume_state(vol, s);
if (!trs->trso_starting && !trs->trso_stopping)
g_raid_write_metadata(sc, vol, NULL, NULL);
}
return (0);
}
static void
g_raid_tr_raid1_fail_disk(struct g_raid_softc *sc, struct g_raid_subdisk *sd,
struct g_raid_disk *disk)
{
/*
* We don't fail the last disk in the pack, since it still has decent
* data on it and that's better than failing the disk if it is the root
* file system.
*
* XXX should this be controlled via a tunable? It makes sense for
* the volume that has / on it. I can't think of a case where we'd
* want the volume to go away on this kind of event.
*/
if (g_raid_nsubdisks(sd->sd_volume, G_RAID_SUBDISK_S_ACTIVE) == 1 &&
g_raid_get_subdisk(sd->sd_volume, G_RAID_SUBDISK_S_ACTIVE) == sd)
return;
g_raid_fail_disk(sc, sd, disk);
}
static void
g_raid_tr_raid1_rebuild_some(struct g_raid_tr_object *tr)
{
struct g_raid_tr_raid1_object *trs;
struct g_raid_subdisk *sd, *good_sd;
struct bio *bp;
trs = (struct g_raid_tr_raid1_object *)tr;
if (trs->trso_flags & TR_RAID1_F_DOING_SOME)
return;
sd = trs->trso_failed_sd;
good_sd = g_raid_get_subdisk(sd->sd_volume, G_RAID_SUBDISK_S_ACTIVE);
if (good_sd == NULL) {
g_raid_tr_raid1_rebuild_abort(tr);
return;
}
bp = &trs->trso_bio;
memset(bp, 0, sizeof(*bp));
bp->bio_offset = sd->sd_rebuild_pos;
bp->bio_length = MIN(g_raid1_rebuild_slab,
sd->sd_size - sd->sd_rebuild_pos);
bp->bio_data = trs->trso_buffer;
bp->bio_cmd = BIO_READ;
bp->bio_cflags = G_RAID_BIO_FLAG_SYNC;
bp->bio_caller1 = good_sd;
trs->trso_flags |= TR_RAID1_F_DOING_SOME;
trs->trso_flags |= TR_RAID1_F_LOCKED;
g_raid_lock_range(sd->sd_volume, /* Lock callback starts I/O */
bp->bio_offset, bp->bio_length, NULL, bp);
}
static void
g_raid_tr_raid1_rebuild_done(struct g_raid_tr_raid1_object *trs)
{
struct g_raid_volume *vol;
struct g_raid_subdisk *sd;
vol = trs->trso_base.tro_volume;
sd = trs->trso_failed_sd;
g_raid_write_metadata(vol->v_softc, vol, sd, sd->sd_disk);
free(trs->trso_buffer, M_TR_RAID1);
trs->trso_buffer = NULL;
trs->trso_flags &= ~TR_RAID1_F_DOING_SOME;
trs->trso_type = TR_RAID1_NONE;
trs->trso_recover_slabs = 0;
trs->trso_failed_sd = NULL;
g_raid_tr_update_state_raid1(vol, NULL);
}
static void
g_raid_tr_raid1_rebuild_finish(struct g_raid_tr_object *tr)
{
struct g_raid_tr_raid1_object *trs;
struct g_raid_subdisk *sd;
trs = (struct g_raid_tr_raid1_object *)tr;
sd = trs->trso_failed_sd;
G_RAID_DEBUG1(0, tr->tro_volume->v_softc,
"Subdisk %s:%d-%s rebuild completed.",
sd->sd_volume->v_name, sd->sd_pos,
sd->sd_disk ? g_raid_get_diskname(sd->sd_disk) : "[none]");
g_raid_change_subdisk_state(sd, G_RAID_SUBDISK_S_ACTIVE);
sd->sd_rebuild_pos = 0;
g_raid_tr_raid1_rebuild_done(trs);
}
static void
g_raid_tr_raid1_rebuild_abort(struct g_raid_tr_object *tr)
{
struct g_raid_tr_raid1_object *trs;
struct g_raid_subdisk *sd;
struct g_raid_volume *vol;
off_t len;
vol = tr->tro_volume;
trs = (struct g_raid_tr_raid1_object *)tr;
sd = trs->trso_failed_sd;
if (trs->trso_flags & TR_RAID1_F_DOING_SOME) {
G_RAID_DEBUG1(1, vol->v_softc,
"Subdisk %s:%d-%s rebuild is aborting.",
sd->sd_volume->v_name, sd->sd_pos,
sd->sd_disk ? g_raid_get_diskname(sd->sd_disk) : "[none]");
trs->trso_flags |= TR_RAID1_F_ABORT;
} else {
G_RAID_DEBUG1(0, vol->v_softc,
"Subdisk %s:%d-%s rebuild aborted.",
sd->sd_volume->v_name, sd->sd_pos,
sd->sd_disk ? g_raid_get_diskname(sd->sd_disk) : "[none]");
trs->trso_flags &= ~TR_RAID1_F_ABORT;
if (trs->trso_flags & TR_RAID1_F_LOCKED) {
trs->trso_flags &= ~TR_RAID1_F_LOCKED;
len = MIN(g_raid1_rebuild_slab,
sd->sd_size - sd->sd_rebuild_pos);
g_raid_unlock_range(tr->tro_volume,
sd->sd_rebuild_pos, len);
}
g_raid_tr_raid1_rebuild_done(trs);
}
}
static void
g_raid_tr_raid1_rebuild_start(struct g_raid_tr_object *tr)
{
struct g_raid_volume *vol;
struct g_raid_tr_raid1_object *trs;
struct g_raid_subdisk *sd, *fsd;
vol = tr->tro_volume;
trs = (struct g_raid_tr_raid1_object *)tr;
if (trs->trso_failed_sd) {
G_RAID_DEBUG1(1, vol->v_softc,
"Already rebuild in start rebuild. pos %jd\n",
(intmax_t)trs->trso_failed_sd->sd_rebuild_pos);
return;
}
sd = g_raid_get_subdisk(vol, G_RAID_SUBDISK_S_ACTIVE);
if (sd == NULL) {
G_RAID_DEBUG1(1, vol->v_softc,
"No active disk to rebuild. night night.");
return;
}
fsd = g_raid_get_subdisk(vol, G_RAID_SUBDISK_S_RESYNC);
if (fsd == NULL)
fsd = g_raid_get_subdisk(vol, G_RAID_SUBDISK_S_REBUILD);
if (fsd == NULL) {
fsd = g_raid_get_subdisk(vol, G_RAID_SUBDISK_S_STALE);
if (fsd != NULL) {
fsd->sd_rebuild_pos = 0;
g_raid_change_subdisk_state(fsd,
G_RAID_SUBDISK_S_RESYNC);
g_raid_write_metadata(vol->v_softc, vol, fsd, NULL);
} else {
fsd = g_raid_get_subdisk(vol,
G_RAID_SUBDISK_S_UNINITIALIZED);
if (fsd == NULL)
fsd = g_raid_get_subdisk(vol,
G_RAID_SUBDISK_S_NEW);
if (fsd != NULL) {
fsd->sd_rebuild_pos = 0;
g_raid_change_subdisk_state(fsd,
G_RAID_SUBDISK_S_REBUILD);
g_raid_write_metadata(vol->v_softc,
vol, fsd, NULL);
}
}
}
if (fsd == NULL) {
G_RAID_DEBUG1(1, vol->v_softc,
"No failed disk to rebuild. night night.");
return;
}
trs->trso_failed_sd = fsd;
G_RAID_DEBUG1(0, vol->v_softc,
"Subdisk %s:%d-%s rebuild start at %jd.",
fsd->sd_volume->v_name, fsd->sd_pos,
fsd->sd_disk ? g_raid_get_diskname(fsd->sd_disk) : "[none]",
trs->trso_failed_sd->sd_rebuild_pos);
trs->trso_type = TR_RAID1_REBUILD;
trs->trso_buffer = malloc(g_raid1_rebuild_slab, M_TR_RAID1, M_WAITOK);
trs->trso_meta_update = g_raid1_rebuild_meta_update;
g_raid_tr_raid1_rebuild_some(tr);
}
static void
g_raid_tr_raid1_maybe_rebuild(struct g_raid_tr_object *tr,
struct g_raid_subdisk *sd)
{
struct g_raid_volume *vol;
struct g_raid_tr_raid1_object *trs;
int na, nr;
/*
* If we're stopping, don't do anything. If we don't have at least one
* good disk and one bad disk, we don't do anything. And if there's a
* 'good disk' stored in the trs, then we're in progress and we punt.
* If we make it past all these checks, we need to rebuild.
*/
vol = tr->tro_volume;
trs = (struct g_raid_tr_raid1_object *)tr;
if (trs->trso_stopping)
return;
na = g_raid_nsubdisks(vol, G_RAID_SUBDISK_S_ACTIVE);
nr = g_raid_nsubdisks(vol, G_RAID_SUBDISK_S_REBUILD) +
g_raid_nsubdisks(vol, G_RAID_SUBDISK_S_RESYNC);
switch(trs->trso_type) {
case TR_RAID1_NONE:
if (na == 0)
return;
if (nr == 0) {
nr = g_raid_nsubdisks(vol, G_RAID_SUBDISK_S_NEW) +
g_raid_nsubdisks(vol, G_RAID_SUBDISK_S_STALE) +
g_raid_nsubdisks(vol, G_RAID_SUBDISK_S_UNINITIALIZED);
if (nr == 0)
return;
}
g_raid_tr_raid1_rebuild_start(tr);
break;
case TR_RAID1_REBUILD:
if (na == 0 || nr == 0 || trs->trso_failed_sd == sd)
g_raid_tr_raid1_rebuild_abort(tr);
break;
case TR_RAID1_RESYNC:
break;
}
}
static int
g_raid_tr_event_raid1(struct g_raid_tr_object *tr,
struct g_raid_subdisk *sd, u_int event)
{
g_raid_tr_update_state_raid1(tr->tro_volume, sd);
return (0);
}
static int
g_raid_tr_start_raid1(struct g_raid_tr_object *tr)
{
struct g_raid_tr_raid1_object *trs;
struct g_raid_volume *vol;
trs = (struct g_raid_tr_raid1_object *)tr;
vol = tr->tro_volume;
trs->trso_starting = 0;
g_raid_tr_update_state_raid1(vol, NULL);
return (0);
}
static int
g_raid_tr_stop_raid1(struct g_raid_tr_object *tr)
{
struct g_raid_tr_raid1_object *trs;
struct g_raid_volume *vol;
trs = (struct g_raid_tr_raid1_object *)tr;
vol = tr->tro_volume;
trs->trso_starting = 0;
trs->trso_stopping = 1;
g_raid_tr_update_state_raid1(vol, NULL);
return (0);
}
/*
* Select the disk to read from. Take into account: subdisk state, running
* error recovery, average disk load, head position and possible cache hits.
*/
#define ABS(x) (((x) >= 0) ? (x) : (-(x)))
static struct g_raid_subdisk *
g_raid_tr_raid1_select_read_disk(struct g_raid_volume *vol, struct bio *bp,
u_int mask)
{
struct g_raid_subdisk *sd, *best;
int i, prio, bestprio;
best = NULL;
bestprio = INT_MAX;
for (i = 0; i < vol->v_disks_count; i++) {
sd = &vol->v_subdisks[i];
if (sd->sd_state != G_RAID_SUBDISK_S_ACTIVE &&
((sd->sd_state != G_RAID_SUBDISK_S_REBUILD &&
sd->sd_state != G_RAID_SUBDISK_S_RESYNC) ||
bp->bio_offset + bp->bio_length > sd->sd_rebuild_pos))
continue;
if ((mask & (1 << i)) != 0)
continue;
prio = G_RAID_SUBDISK_LOAD(sd);
prio += min(sd->sd_recovery, 255) << 22;
prio += (G_RAID_SUBDISK_S_ACTIVE - sd->sd_state) << 16;
/* If disk head is precisely in position - highly prefer it. */
if (G_RAID_SUBDISK_POS(sd) == bp->bio_offset)
prio -= 2 * G_RAID_SUBDISK_LOAD_SCALE;
else
/* If disk head is close to position - prefer it. */
if (ABS(G_RAID_SUBDISK_POS(sd) - bp->bio_offset) <
G_RAID_SUBDISK_TRACK_SIZE)
prio -= 1 * G_RAID_SUBDISK_LOAD_SCALE;
if (prio < bestprio) {
best = sd;
bestprio = prio;
}
}
return (best);
}
static void
g_raid_tr_iostart_raid1_read(struct g_raid_tr_object *tr, struct bio *bp)
{
struct g_raid_subdisk *sd;
struct bio *cbp;
sd = g_raid_tr_raid1_select_read_disk(tr->tro_volume, bp, 0);
KASSERT(sd != NULL, ("No active disks in volume %s.",
tr->tro_volume->v_name));
cbp = g_clone_bio(bp);
if (cbp == NULL) {
g_raid_iodone(bp, ENOMEM);
return;
}
g_raid_subdisk_iostart(sd, cbp);
}
static void
g_raid_tr_iostart_raid1_write(struct g_raid_tr_object *tr, struct bio *bp)
{
struct g_raid_volume *vol;
struct g_raid_subdisk *sd;
struct bio_queue_head queue;
struct bio *cbp;
int i;
vol = tr->tro_volume;
/*
* Allocate all bios before sending any request, so we can return
* ENOMEM in nice and clean way.
*/
bioq_init(&queue);
for (i = 0; i < vol->v_disks_count; i++) {
sd = &vol->v_subdisks[i];
switch (sd->sd_state) {
case G_RAID_SUBDISK_S_ACTIVE:
break;
case G_RAID_SUBDISK_S_REBUILD:
/*
* When rebuilding, only part of this subdisk is
* writable, the rest will be written as part of the
* that process.
*/
if (bp->bio_offset >= sd->sd_rebuild_pos)
continue;
break;
case G_RAID_SUBDISK_S_STALE:
case G_RAID_SUBDISK_S_RESYNC:
/*
* Resyncing still writes on the theory that the
* resync'd disk is very close and writing it will
* keep it that way better if we keep up while
* resyncing.
*/
break;
default:
continue;
}
cbp = g_clone_bio(bp);
if (cbp == NULL)
goto failure;
cbp->bio_caller1 = sd;
bioq_insert_tail(&queue, cbp);
}
while ((cbp = bioq_takefirst(&queue)) != NULL) {
sd = cbp->bio_caller1;
cbp->bio_caller1 = NULL;
g_raid_subdisk_iostart(sd, cbp);
}
return;
failure:
while ((cbp = bioq_takefirst(&queue)) != NULL)
g_destroy_bio(cbp);
if (bp->bio_error == 0)
bp->bio_error = ENOMEM;
g_raid_iodone(bp, bp->bio_error);
}
static void
g_raid_tr_iostart_raid1(struct g_raid_tr_object *tr, struct bio *bp)
{
struct g_raid_volume *vol;
struct g_raid_tr_raid1_object *trs;
vol = tr->tro_volume;
trs = (struct g_raid_tr_raid1_object *)tr;
if (vol->v_state != G_RAID_VOLUME_S_OPTIMAL &&
vol->v_state != G_RAID_VOLUME_S_SUBOPTIMAL &&
vol->v_state != G_RAID_VOLUME_S_DEGRADED) {
g_raid_iodone(bp, EIO);
return;
}
/*
* If we're rebuilding, squeeze in rebuild activity every so often,
* even when the disk is busy. Be sure to only count real I/O
* to the disk. All 'SPECIAL' I/O is traffic generated to the disk
* by this module.
*/
if (trs->trso_failed_sd != NULL &&
!(bp->bio_cflags & G_RAID_BIO_FLAG_SPECIAL)) {
/* Make this new or running now round short. */
trs->trso_recover_slabs = 0;
if (--trs->trso_fair_io <= 0) {
trs->trso_fair_io = g_raid1_rebuild_fair_io;
g_raid_tr_raid1_rebuild_some(tr);
}
}
switch (bp->bio_cmd) {
case BIO_READ:
g_raid_tr_iostart_raid1_read(tr, bp);
break;
case BIO_WRITE:
case BIO_DELETE:
g_raid_tr_iostart_raid1_write(tr, bp);
break;
case BIO_FLUSH:
g_raid_tr_flush_common(tr, bp);
break;
default:
KASSERT(1 == 0, ("Invalid command here: %u (volume=%s)",
bp->bio_cmd, vol->v_name));
break;
}
}
static void
g_raid_tr_iodone_raid1(struct g_raid_tr_object *tr,
struct g_raid_subdisk *sd, struct bio *bp)
{
struct bio *cbp;
struct g_raid_subdisk *nsd;
struct g_raid_volume *vol;
struct bio *pbp;
struct g_raid_tr_raid1_object *trs;
uintptr_t *mask;
int error, do_write;
trs = (struct g_raid_tr_raid1_object *)tr;
vol = tr->tro_volume;
if (bp->bio_cflags & G_RAID_BIO_FLAG_SYNC) {
/*
* This operation is part of a rebuild or resync operation.
* See what work just got done, then schedule the next bit of
* work, if any. Rebuild/resync is done a little bit at a
* time. Either when a timeout happens, or after we get a
* bunch of I/Os to the disk (to make sure an active system
* will complete in a sane amount of time).
*
* We are setup to do differing amounts of work for each of
* these cases. so long as the slabs is smallish (less than
* 50 or so, I'd guess, but that's just a WAG), we shouldn't
* have any bio starvation issues. For active disks, we do
* 5MB of data, for inactive ones, we do 50MB.
*/
if (trs->trso_type == TR_RAID1_REBUILD) {
if (bp->bio_cmd == BIO_READ) {
/* Immediately abort rebuild, if requested. */
if (trs->trso_flags & TR_RAID1_F_ABORT) {
trs->trso_flags &= ~TR_RAID1_F_DOING_SOME;
g_raid_tr_raid1_rebuild_abort(tr);
return;
}
/* On read error, skip and cross fingers. */
if (bp->bio_error != 0) {
G_RAID_LOGREQ(0, bp,
"Read error during rebuild (%d), "
"possible data loss!",
bp->bio_error);
goto rebuild_round_done;
}
/*
* The read operation finished, queue the
* write and get out.
*/
G_RAID_LOGREQ(4, bp, "rebuild read done. %d",
bp->bio_error);
bp->bio_cmd = BIO_WRITE;
bp->bio_cflags = G_RAID_BIO_FLAG_SYNC;
G_RAID_LOGREQ(4, bp, "Queueing rebuild write.");
g_raid_subdisk_iostart(trs->trso_failed_sd, bp);
} else {
/*
* The write operation just finished. Do
* another. We keep cloning the master bio
* since it has the right buffers allocated to
* it.
*/
G_RAID_LOGREQ(4, bp,
"rebuild write done. Error %d",
bp->bio_error);
nsd = trs->trso_failed_sd;
if (bp->bio_error != 0 ||
trs->trso_flags & TR_RAID1_F_ABORT) {
if ((trs->trso_flags &
TR_RAID1_F_ABORT) == 0) {
g_raid_tr_raid1_fail_disk(sd->sd_softc,
nsd, nsd->sd_disk);
}
trs->trso_flags &= ~TR_RAID1_F_DOING_SOME;
g_raid_tr_raid1_rebuild_abort(tr);
return;
}
rebuild_round_done:
nsd = trs->trso_failed_sd;
trs->trso_flags &= ~TR_RAID1_F_LOCKED;
g_raid_unlock_range(sd->sd_volume,
bp->bio_offset, bp->bio_length);
nsd->sd_rebuild_pos += bp->bio_length;
if (nsd->sd_rebuild_pos >= nsd->sd_size) {
g_raid_tr_raid1_rebuild_finish(tr);
return;
}
/* Abort rebuild if we are stopping */
if (trs->trso_stopping) {
trs->trso_flags &= ~TR_RAID1_F_DOING_SOME;
g_raid_tr_raid1_rebuild_abort(tr);
return;
}
if (--trs->trso_meta_update <= 0) {
g_raid_write_metadata(vol->v_softc,
vol, nsd, nsd->sd_disk);
trs->trso_meta_update =
g_raid1_rebuild_meta_update;
}
trs->trso_flags &= ~TR_RAID1_F_DOING_SOME;
if (--trs->trso_recover_slabs <= 0)
return;
g_raid_tr_raid1_rebuild_some(tr);
}
} else if (trs->trso_type == TR_RAID1_RESYNC) {
/*
* read good sd, read bad sd in parallel. when both
* done, compare the buffers. write good to the bad
* if different. do the next bit of work.
*/
panic("Somehow, we think we're doing a resync");
}
return;
}
pbp = bp->bio_parent;
pbp->bio_inbed++;
if (bp->bio_cmd == BIO_READ && bp->bio_error != 0) {
/*
* Read failed on first drive. Retry the read error on
* another disk drive, if available, before erroring out the
* read.
*/
sd->sd_disk->d_read_errs++;
G_RAID_LOGREQ(0, bp,
"Read error (%d), %d read errors total",
bp->bio_error, sd->sd_disk->d_read_errs);
/*
* If there are too many read errors, we move to degraded.
* XXX Do we want to FAIL the drive (eg, make the user redo
* everything to get it back in sync), or just degrade the
* drive, which kicks off a resync?
*/
do_write = 1;
if (sd->sd_disk->d_read_errs > g_raid_read_err_thresh) {
g_raid_tr_raid1_fail_disk(sd->sd_softc, sd, sd->sd_disk);
if (pbp->bio_children == 1)
do_write = 0;
}
/*
* Find the other disk, and try to do the I/O to it.
*/
mask = (uintptr_t *)(&pbp->bio_driver2);
if (pbp->bio_children == 1) {
/* Save original subdisk. */
pbp->bio_driver1 = do_write ? sd : NULL;
*mask = 0;
}
*mask |= 1 << sd->sd_pos;
nsd = g_raid_tr_raid1_select_read_disk(vol, pbp, *mask);
if (nsd != NULL && (cbp = g_clone_bio(pbp)) != NULL) {
g_destroy_bio(bp);
G_RAID_LOGREQ(2, cbp, "Retrying read from %d",
nsd->sd_pos);
if (pbp->bio_children == 2 && do_write) {
sd->sd_recovery++;
cbp->bio_caller1 = nsd;
pbp->bio_pflags = G_RAID_BIO_FLAG_LOCKED;
/* Lock callback starts I/O */
g_raid_lock_range(sd->sd_volume,
cbp->bio_offset, cbp->bio_length, pbp, cbp);
} else {
g_raid_subdisk_iostart(nsd, cbp);
}
return;
}
/*
* We can't retry. Return the original error by falling
* through. This will happen when there's only one good disk.
* We don't need to fail the raid, since its actual state is
* based on the state of the subdisks.
*/
G_RAID_LOGREQ(2, bp, "Couldn't retry read, failing it");
}
if (bp->bio_cmd == BIO_READ &&
bp->bio_error == 0 &&
pbp->bio_children > 1 &&
pbp->bio_driver1 != NULL) {
/*
* If it was a read, and bio_children is >1, then we just
* recovered the data from the second drive. We should try to
* write that data to the first drive if sector remapping is
* enabled. A write should put the data in a new place on the
* disk, remapping the bad sector. Do we need to do that by
* queueing a request to the main worker thread? It doesn't
* affect the return code of this current read, and can be
* done at our liesure. However, to make the code simpler, it
* is done syncrhonously.
*/
G_RAID_LOGREQ(3, bp, "Recovered data from other drive");
cbp = g_clone_bio(pbp);
if (cbp != NULL) {
g_destroy_bio(bp);
cbp->bio_cmd = BIO_WRITE;
cbp->bio_cflags = G_RAID_BIO_FLAG_REMAP;
G_RAID_LOGREQ(2, cbp,
"Attempting bad sector remap on failing drive.");
g_raid_subdisk_iostart(pbp->bio_driver1, cbp);
return;
}
}
if (pbp->bio_pflags & G_RAID_BIO_FLAG_LOCKED) {
/*
* We're done with a recovery, mark the range as unlocked.
* For any write errors, we agressively fail the disk since
* there was both a READ and a WRITE error at this location.
* Both types of errors generally indicates the drive is on
* the verge of total failure anyway. Better to stop trusting
* it now. However, we need to reset error to 0 in that case
* because we're not failing the original I/O which succeeded.
*/
if (bp->bio_cmd == BIO_WRITE && bp->bio_error) {
G_RAID_LOGREQ(0, bp, "Remap write failed: "
"failing subdisk.");
g_raid_tr_raid1_fail_disk(sd->sd_softc, sd, sd->sd_disk);
bp->bio_error = 0;
}
if (pbp->bio_driver1 != NULL) {
((struct g_raid_subdisk *)pbp->bio_driver1)
->sd_recovery--;
}
G_RAID_LOGREQ(2, bp, "REMAP done %d.", bp->bio_error);
g_raid_unlock_range(sd->sd_volume, bp->bio_offset,
bp->bio_length);
}
if (pbp->bio_cmd != BIO_READ) {
if (pbp->bio_inbed == 1 || pbp->bio_error != 0)
pbp->bio_error = bp->bio_error;
if (pbp->bio_cmd == BIO_WRITE && bp->bio_error != 0) {
G_RAID_LOGREQ(0, bp, "Write failed: failing subdisk.");
g_raid_tr_raid1_fail_disk(sd->sd_softc, sd, sd->sd_disk);
}
error = pbp->bio_error;
} else
error = bp->bio_error;
g_destroy_bio(bp);
if (pbp->bio_children == pbp->bio_inbed) {
pbp->bio_completed = pbp->bio_length;
g_raid_iodone(pbp, error);
}
}
static int
g_raid_tr_kerneldump_raid1(struct g_raid_tr_object *tr,
void *virtual, vm_offset_t physical, off_t offset, size_t length)
{
struct g_raid_volume *vol;
struct g_raid_subdisk *sd;
int error, i, ok;
vol = tr->tro_volume;
error = 0;
ok = 0;
for (i = 0; i < vol->v_disks_count; i++) {
sd = &vol->v_subdisks[i];
switch (sd->sd_state) {
case G_RAID_SUBDISK_S_ACTIVE:
break;
case G_RAID_SUBDISK_S_REBUILD:
/*
* When rebuilding, only part of this subdisk is
* writable, the rest will be written as part of the
* that process.
*/
if (offset >= sd->sd_rebuild_pos)
continue;
break;
case G_RAID_SUBDISK_S_STALE:
case G_RAID_SUBDISK_S_RESYNC:
/*
* Resyncing still writes on the theory that the
* resync'd disk is very close and writing it will
* keep it that way better if we keep up while
* resyncing.
*/
break;
default:
continue;
}
error = g_raid_subdisk_kerneldump(sd,
virtual, physical, offset, length);
if (error == 0)
ok++;
}
return (ok > 0 ? 0 : error);
}
static int
g_raid_tr_locked_raid1(struct g_raid_tr_object *tr, void *argp)
{
struct bio *bp;
struct g_raid_subdisk *sd;
bp = (struct bio *)argp;
sd = (struct g_raid_subdisk *)bp->bio_caller1;
g_raid_subdisk_iostart(sd, bp);
return (0);
}
static int
g_raid_tr_idle_raid1(struct g_raid_tr_object *tr)
{
struct g_raid_tr_raid1_object *trs;
trs = (struct g_raid_tr_raid1_object *)tr;
trs->trso_fair_io = g_raid1_rebuild_fair_io;
trs->trso_recover_slabs = g_raid1_rebuild_cluster_idle;
if (trs->trso_type == TR_RAID1_REBUILD)
g_raid_tr_raid1_rebuild_some(tr);
return (0);
}
static int
g_raid_tr_free_raid1(struct g_raid_tr_object *tr)
{
struct g_raid_tr_raid1_object *trs;
trs = (struct g_raid_tr_raid1_object *)tr;
if (trs->trso_buffer != NULL) {
free(trs->trso_buffer, M_TR_RAID1);
trs->trso_buffer = NULL;
}
return (0);
}
G_RAID_TR_DECLARE(raid1, "RAID1");