mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-27 03:10:12 +00:00
![Yu Zhe](/assets/img/avatar_default.png)
Pointer variables of void * type do not require type cast. Signed-off-by: Yu Zhe <yuzhe@nfschina.com> Signed-off-by: Mike Snitzer <snitzer@kernel.org>
1530 lines
36 KiB
C
1530 lines
36 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
|
|
/*
|
|
* Copyright (C) 2003 Sistina Software Limited.
|
|
* Copyright (C) 2005-2008 Red Hat, Inc. All rights reserved.
|
|
*
|
|
* This file is released under the GPL.
|
|
*/
|
|
|
|
#include "dm-bio-record.h"
|
|
|
|
#include <linux/init.h>
|
|
#include <linux/mempool.h>
|
|
#include <linux/module.h>
|
|
#include <linux/pagemap.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/workqueue.h>
|
|
#include <linux/device-mapper.h>
|
|
#include <linux/dm-io.h>
|
|
#include <linux/dm-dirty-log.h>
|
|
#include <linux/dm-kcopyd.h>
|
|
#include <linux/dm-region-hash.h>
|
|
|
|
static struct workqueue_struct *dm_raid1_wq;
|
|
|
|
#define DM_MSG_PREFIX "raid1"
|
|
|
|
#define MAX_RECOVERY 1 /* Maximum number of regions recovered in parallel. */
|
|
|
|
#define MAX_NR_MIRRORS (DM_KCOPYD_MAX_REGIONS + 1)
|
|
|
|
#define DM_RAID1_HANDLE_ERRORS 0x01
|
|
#define DM_RAID1_KEEP_LOG 0x02
|
|
#define errors_handled(p) ((p)->features & DM_RAID1_HANDLE_ERRORS)
|
|
#define keep_log(p) ((p)->features & DM_RAID1_KEEP_LOG)
|
|
|
|
static DECLARE_WAIT_QUEUE_HEAD(_kmirrord_recovery_stopped);
|
|
|
|
/*
|
|
*---------------------------------------------------------------
|
|
* Mirror set structures.
|
|
*---------------------------------------------------------------
|
|
*/
|
|
enum dm_raid1_error {
|
|
DM_RAID1_WRITE_ERROR,
|
|
DM_RAID1_FLUSH_ERROR,
|
|
DM_RAID1_SYNC_ERROR,
|
|
DM_RAID1_READ_ERROR
|
|
};
|
|
|
|
struct mirror {
|
|
struct mirror_set *ms;
|
|
atomic_t error_count;
|
|
unsigned long error_type;
|
|
struct dm_dev *dev;
|
|
sector_t offset;
|
|
};
|
|
|
|
struct mirror_set {
|
|
struct dm_target *ti;
|
|
struct list_head list;
|
|
|
|
uint64_t features;
|
|
|
|
spinlock_t lock; /* protects the lists */
|
|
struct bio_list reads;
|
|
struct bio_list writes;
|
|
struct bio_list failures;
|
|
struct bio_list holds; /* bios are waiting until suspend */
|
|
|
|
struct dm_region_hash *rh;
|
|
struct dm_kcopyd_client *kcopyd_client;
|
|
struct dm_io_client *io_client;
|
|
|
|
/* recovery */
|
|
region_t nr_regions;
|
|
int in_sync;
|
|
int log_failure;
|
|
int leg_failure;
|
|
atomic_t suspend;
|
|
|
|
atomic_t default_mirror; /* Default mirror */
|
|
|
|
struct workqueue_struct *kmirrord_wq;
|
|
struct work_struct kmirrord_work;
|
|
struct timer_list timer;
|
|
unsigned long timer_pending;
|
|
|
|
struct work_struct trigger_event;
|
|
|
|
unsigned int nr_mirrors;
|
|
struct mirror mirror[];
|
|
};
|
|
|
|
DECLARE_DM_KCOPYD_THROTTLE_WITH_MODULE_PARM(raid1_resync_throttle,
|
|
"A percentage of time allocated for raid resynchronization");
|
|
|
|
static void wakeup_mirrord(void *context)
|
|
{
|
|
struct mirror_set *ms = context;
|
|
|
|
queue_work(ms->kmirrord_wq, &ms->kmirrord_work);
|
|
}
|
|
|
|
static void delayed_wake_fn(struct timer_list *t)
|
|
{
|
|
struct mirror_set *ms = from_timer(ms, t, timer);
|
|
|
|
clear_bit(0, &ms->timer_pending);
|
|
wakeup_mirrord(ms);
|
|
}
|
|
|
|
static void delayed_wake(struct mirror_set *ms)
|
|
{
|
|
if (test_and_set_bit(0, &ms->timer_pending))
|
|
return;
|
|
|
|
ms->timer.expires = jiffies + HZ / 5;
|
|
add_timer(&ms->timer);
|
|
}
|
|
|
|
static void wakeup_all_recovery_waiters(void *context)
|
|
{
|
|
wake_up_all(&_kmirrord_recovery_stopped);
|
|
}
|
|
|
|
static void queue_bio(struct mirror_set *ms, struct bio *bio, int rw)
|
|
{
|
|
unsigned long flags;
|
|
int should_wake = 0;
|
|
struct bio_list *bl;
|
|
|
|
bl = (rw == WRITE) ? &ms->writes : &ms->reads;
|
|
spin_lock_irqsave(&ms->lock, flags);
|
|
should_wake = !(bl->head);
|
|
bio_list_add(bl, bio);
|
|
spin_unlock_irqrestore(&ms->lock, flags);
|
|
|
|
if (should_wake)
|
|
wakeup_mirrord(ms);
|
|
}
|
|
|
|
static void dispatch_bios(void *context, struct bio_list *bio_list)
|
|
{
|
|
struct mirror_set *ms = context;
|
|
struct bio *bio;
|
|
|
|
while ((bio = bio_list_pop(bio_list)))
|
|
queue_bio(ms, bio, WRITE);
|
|
}
|
|
|
|
struct dm_raid1_bio_record {
|
|
struct mirror *m;
|
|
/* if details->bi_bdev == NULL, details were not saved */
|
|
struct dm_bio_details details;
|
|
region_t write_region;
|
|
};
|
|
|
|
/*
|
|
* Every mirror should look like this one.
|
|
*/
|
|
#define DEFAULT_MIRROR 0
|
|
|
|
/*
|
|
* This is yucky. We squirrel the mirror struct away inside
|
|
* bi_next for read/write buffers. This is safe since the bh
|
|
* doesn't get submitted to the lower levels of block layer.
|
|
*/
|
|
static struct mirror *bio_get_m(struct bio *bio)
|
|
{
|
|
return (struct mirror *) bio->bi_next;
|
|
}
|
|
|
|
static void bio_set_m(struct bio *bio, struct mirror *m)
|
|
{
|
|
bio->bi_next = (struct bio *) m;
|
|
}
|
|
|
|
static struct mirror *get_default_mirror(struct mirror_set *ms)
|
|
{
|
|
return &ms->mirror[atomic_read(&ms->default_mirror)];
|
|
}
|
|
|
|
static void set_default_mirror(struct mirror *m)
|
|
{
|
|
struct mirror_set *ms = m->ms;
|
|
struct mirror *m0 = &(ms->mirror[0]);
|
|
|
|
atomic_set(&ms->default_mirror, m - m0);
|
|
}
|
|
|
|
static struct mirror *get_valid_mirror(struct mirror_set *ms)
|
|
{
|
|
struct mirror *m;
|
|
|
|
for (m = ms->mirror; m < ms->mirror + ms->nr_mirrors; m++)
|
|
if (!atomic_read(&m->error_count))
|
|
return m;
|
|
|
|
return NULL;
|
|
}
|
|
|
|
/* fail_mirror
|
|
* @m: mirror device to fail
|
|
* @error_type: one of the enum's, DM_RAID1_*_ERROR
|
|
*
|
|
* If errors are being handled, record the type of
|
|
* error encountered for this device. If this type
|
|
* of error has already been recorded, we can return;
|
|
* otherwise, we must signal userspace by triggering
|
|
* an event. Additionally, if the device is the
|
|
* primary device, we must choose a new primary, but
|
|
* only if the mirror is in-sync.
|
|
*
|
|
* This function must not block.
|
|
*/
|
|
static void fail_mirror(struct mirror *m, enum dm_raid1_error error_type)
|
|
{
|
|
struct mirror_set *ms = m->ms;
|
|
struct mirror *new;
|
|
|
|
ms->leg_failure = 1;
|
|
|
|
/*
|
|
* error_count is used for nothing more than a
|
|
* simple way to tell if a device has encountered
|
|
* errors.
|
|
*/
|
|
atomic_inc(&m->error_count);
|
|
|
|
if (test_and_set_bit(error_type, &m->error_type))
|
|
return;
|
|
|
|
if (!errors_handled(ms))
|
|
return;
|
|
|
|
if (m != get_default_mirror(ms))
|
|
goto out;
|
|
|
|
if (!ms->in_sync && !keep_log(ms)) {
|
|
/*
|
|
* Better to issue requests to same failing device
|
|
* than to risk returning corrupt data.
|
|
*/
|
|
DMERR("Primary mirror (%s) failed while out-of-sync: Reads may fail.",
|
|
m->dev->name);
|
|
goto out;
|
|
}
|
|
|
|
new = get_valid_mirror(ms);
|
|
if (new)
|
|
set_default_mirror(new);
|
|
else
|
|
DMWARN("All sides of mirror have failed.");
|
|
|
|
out:
|
|
queue_work(dm_raid1_wq, &ms->trigger_event);
|
|
}
|
|
|
|
static int mirror_flush(struct dm_target *ti)
|
|
{
|
|
struct mirror_set *ms = ti->private;
|
|
unsigned long error_bits;
|
|
|
|
unsigned int i;
|
|
struct dm_io_region io[MAX_NR_MIRRORS];
|
|
struct mirror *m;
|
|
struct dm_io_request io_req = {
|
|
.bi_opf = REQ_OP_WRITE | REQ_PREFLUSH | REQ_SYNC,
|
|
.mem.type = DM_IO_KMEM,
|
|
.mem.ptr.addr = NULL,
|
|
.client = ms->io_client,
|
|
};
|
|
|
|
for (i = 0, m = ms->mirror; i < ms->nr_mirrors; i++, m++) {
|
|
io[i].bdev = m->dev->bdev;
|
|
io[i].sector = 0;
|
|
io[i].count = 0;
|
|
}
|
|
|
|
error_bits = -1;
|
|
dm_io(&io_req, ms->nr_mirrors, io, &error_bits);
|
|
if (unlikely(error_bits != 0)) {
|
|
for (i = 0; i < ms->nr_mirrors; i++)
|
|
if (test_bit(i, &error_bits))
|
|
fail_mirror(ms->mirror + i,
|
|
DM_RAID1_FLUSH_ERROR);
|
|
return -EIO;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
*---------------------------------------------------------------
|
|
* Recovery.
|
|
*
|
|
* When a mirror is first activated we may find that some regions
|
|
* are in the no-sync state. We have to recover these by
|
|
* recopying from the default mirror to all the others.
|
|
*---------------------------------------------------------------
|
|
*/
|
|
static void recovery_complete(int read_err, unsigned long write_err,
|
|
void *context)
|
|
{
|
|
struct dm_region *reg = context;
|
|
struct mirror_set *ms = dm_rh_region_context(reg);
|
|
int m, bit = 0;
|
|
|
|
if (read_err) {
|
|
/* Read error means the failure of default mirror. */
|
|
DMERR_LIMIT("Unable to read primary mirror during recovery");
|
|
fail_mirror(get_default_mirror(ms), DM_RAID1_SYNC_ERROR);
|
|
}
|
|
|
|
if (write_err) {
|
|
DMERR_LIMIT("Write error during recovery (error = 0x%lx)",
|
|
write_err);
|
|
/*
|
|
* Bits correspond to devices (excluding default mirror).
|
|
* The default mirror cannot change during recovery.
|
|
*/
|
|
for (m = 0; m < ms->nr_mirrors; m++) {
|
|
if (&ms->mirror[m] == get_default_mirror(ms))
|
|
continue;
|
|
if (test_bit(bit, &write_err))
|
|
fail_mirror(ms->mirror + m,
|
|
DM_RAID1_SYNC_ERROR);
|
|
bit++;
|
|
}
|
|
}
|
|
|
|
dm_rh_recovery_end(reg, !(read_err || write_err));
|
|
}
|
|
|
|
static void recover(struct mirror_set *ms, struct dm_region *reg)
|
|
{
|
|
unsigned int i;
|
|
struct dm_io_region from, to[DM_KCOPYD_MAX_REGIONS], *dest;
|
|
struct mirror *m;
|
|
unsigned long flags = 0;
|
|
region_t key = dm_rh_get_region_key(reg);
|
|
sector_t region_size = dm_rh_get_region_size(ms->rh);
|
|
|
|
/* fill in the source */
|
|
m = get_default_mirror(ms);
|
|
from.bdev = m->dev->bdev;
|
|
from.sector = m->offset + dm_rh_region_to_sector(ms->rh, key);
|
|
if (key == (ms->nr_regions - 1)) {
|
|
/*
|
|
* The final region may be smaller than
|
|
* region_size.
|
|
*/
|
|
from.count = ms->ti->len & (region_size - 1);
|
|
if (!from.count)
|
|
from.count = region_size;
|
|
} else
|
|
from.count = region_size;
|
|
|
|
/* fill in the destinations */
|
|
for (i = 0, dest = to; i < ms->nr_mirrors; i++) {
|
|
if (&ms->mirror[i] == get_default_mirror(ms))
|
|
continue;
|
|
|
|
m = ms->mirror + i;
|
|
dest->bdev = m->dev->bdev;
|
|
dest->sector = m->offset + dm_rh_region_to_sector(ms->rh, key);
|
|
dest->count = from.count;
|
|
dest++;
|
|
}
|
|
|
|
/* hand to kcopyd */
|
|
if (!errors_handled(ms))
|
|
flags |= BIT(DM_KCOPYD_IGNORE_ERROR);
|
|
|
|
dm_kcopyd_copy(ms->kcopyd_client, &from, ms->nr_mirrors - 1, to,
|
|
flags, recovery_complete, reg);
|
|
}
|
|
|
|
static void reset_ms_flags(struct mirror_set *ms)
|
|
{
|
|
unsigned int m;
|
|
|
|
ms->leg_failure = 0;
|
|
for (m = 0; m < ms->nr_mirrors; m++) {
|
|
atomic_set(&(ms->mirror[m].error_count), 0);
|
|
ms->mirror[m].error_type = 0;
|
|
}
|
|
}
|
|
|
|
static void do_recovery(struct mirror_set *ms)
|
|
{
|
|
struct dm_region *reg;
|
|
struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh);
|
|
|
|
/*
|
|
* Start quiescing some regions.
|
|
*/
|
|
dm_rh_recovery_prepare(ms->rh);
|
|
|
|
/*
|
|
* Copy any already quiesced regions.
|
|
*/
|
|
while ((reg = dm_rh_recovery_start(ms->rh)))
|
|
recover(ms, reg);
|
|
|
|
/*
|
|
* Update the in sync flag.
|
|
*/
|
|
if (!ms->in_sync &&
|
|
(log->type->get_sync_count(log) == ms->nr_regions)) {
|
|
/* the sync is complete */
|
|
dm_table_event(ms->ti->table);
|
|
ms->in_sync = 1;
|
|
reset_ms_flags(ms);
|
|
}
|
|
}
|
|
|
|
/*
|
|
*---------------------------------------------------------------
|
|
* Reads
|
|
*---------------------------------------------------------------
|
|
*/
|
|
static struct mirror *choose_mirror(struct mirror_set *ms, sector_t sector)
|
|
{
|
|
struct mirror *m = get_default_mirror(ms);
|
|
|
|
do {
|
|
if (likely(!atomic_read(&m->error_count)))
|
|
return m;
|
|
|
|
if (m-- == ms->mirror)
|
|
m += ms->nr_mirrors;
|
|
} while (m != get_default_mirror(ms));
|
|
|
|
return NULL;
|
|
}
|
|
|
|
static int default_ok(struct mirror *m)
|
|
{
|
|
struct mirror *default_mirror = get_default_mirror(m->ms);
|
|
|
|
return !atomic_read(&default_mirror->error_count);
|
|
}
|
|
|
|
static int mirror_available(struct mirror_set *ms, struct bio *bio)
|
|
{
|
|
struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh);
|
|
region_t region = dm_rh_bio_to_region(ms->rh, bio);
|
|
|
|
if (log->type->in_sync(log, region, 0))
|
|
return choose_mirror(ms, bio->bi_iter.bi_sector) ? 1 : 0;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* remap a buffer to a particular mirror.
|
|
*/
|
|
static sector_t map_sector(struct mirror *m, struct bio *bio)
|
|
{
|
|
if (unlikely(!bio->bi_iter.bi_size))
|
|
return 0;
|
|
return m->offset + dm_target_offset(m->ms->ti, bio->bi_iter.bi_sector);
|
|
}
|
|
|
|
static void map_bio(struct mirror *m, struct bio *bio)
|
|
{
|
|
bio_set_dev(bio, m->dev->bdev);
|
|
bio->bi_iter.bi_sector = map_sector(m, bio);
|
|
}
|
|
|
|
static void map_region(struct dm_io_region *io, struct mirror *m,
|
|
struct bio *bio)
|
|
{
|
|
io->bdev = m->dev->bdev;
|
|
io->sector = map_sector(m, bio);
|
|
io->count = bio_sectors(bio);
|
|
}
|
|
|
|
static void hold_bio(struct mirror_set *ms, struct bio *bio)
|
|
{
|
|
/*
|
|
* Lock is required to avoid race condition during suspend
|
|
* process.
|
|
*/
|
|
spin_lock_irq(&ms->lock);
|
|
|
|
if (atomic_read(&ms->suspend)) {
|
|
spin_unlock_irq(&ms->lock);
|
|
|
|
/*
|
|
* If device is suspended, complete the bio.
|
|
*/
|
|
if (dm_noflush_suspending(ms->ti))
|
|
bio->bi_status = BLK_STS_DM_REQUEUE;
|
|
else
|
|
bio->bi_status = BLK_STS_IOERR;
|
|
|
|
bio_endio(bio);
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* Hold bio until the suspend is complete.
|
|
*/
|
|
bio_list_add(&ms->holds, bio);
|
|
spin_unlock_irq(&ms->lock);
|
|
}
|
|
|
|
/*
|
|
*---------------------------------------------------------------
|
|
* Reads
|
|
*---------------------------------------------------------------
|
|
*/
|
|
static void read_callback(unsigned long error, void *context)
|
|
{
|
|
struct bio *bio = context;
|
|
struct mirror *m;
|
|
|
|
m = bio_get_m(bio);
|
|
bio_set_m(bio, NULL);
|
|
|
|
if (likely(!error)) {
|
|
bio_endio(bio);
|
|
return;
|
|
}
|
|
|
|
fail_mirror(m, DM_RAID1_READ_ERROR);
|
|
|
|
if (likely(default_ok(m)) || mirror_available(m->ms, bio)) {
|
|
DMWARN_LIMIT("Read failure on mirror device %s. Trying alternative device.",
|
|
m->dev->name);
|
|
queue_bio(m->ms, bio, bio_data_dir(bio));
|
|
return;
|
|
}
|
|
|
|
DMERR_LIMIT("Read failure on mirror device %s. Failing I/O.",
|
|
m->dev->name);
|
|
bio_io_error(bio);
|
|
}
|
|
|
|
/* Asynchronous read. */
|
|
static void read_async_bio(struct mirror *m, struct bio *bio)
|
|
{
|
|
struct dm_io_region io;
|
|
struct dm_io_request io_req = {
|
|
.bi_opf = REQ_OP_READ,
|
|
.mem.type = DM_IO_BIO,
|
|
.mem.ptr.bio = bio,
|
|
.notify.fn = read_callback,
|
|
.notify.context = bio,
|
|
.client = m->ms->io_client,
|
|
};
|
|
|
|
map_region(&io, m, bio);
|
|
bio_set_m(bio, m);
|
|
BUG_ON(dm_io(&io_req, 1, &io, NULL));
|
|
}
|
|
|
|
static inline int region_in_sync(struct mirror_set *ms, region_t region,
|
|
int may_block)
|
|
{
|
|
int state = dm_rh_get_state(ms->rh, region, may_block);
|
|
return state == DM_RH_CLEAN || state == DM_RH_DIRTY;
|
|
}
|
|
|
|
static void do_reads(struct mirror_set *ms, struct bio_list *reads)
|
|
{
|
|
region_t region;
|
|
struct bio *bio;
|
|
struct mirror *m;
|
|
|
|
while ((bio = bio_list_pop(reads))) {
|
|
region = dm_rh_bio_to_region(ms->rh, bio);
|
|
m = get_default_mirror(ms);
|
|
|
|
/*
|
|
* We can only read balance if the region is in sync.
|
|
*/
|
|
if (likely(region_in_sync(ms, region, 1)))
|
|
m = choose_mirror(ms, bio->bi_iter.bi_sector);
|
|
else if (m && atomic_read(&m->error_count))
|
|
m = NULL;
|
|
|
|
if (likely(m))
|
|
read_async_bio(m, bio);
|
|
else
|
|
bio_io_error(bio);
|
|
}
|
|
}
|
|
|
|
/*
|
|
*---------------------------------------------------------------------
|
|
* Writes.
|
|
*
|
|
* We do different things with the write io depending on the
|
|
* state of the region that it's in:
|
|
*
|
|
* SYNC: increment pending, use kcopyd to write to *all* mirrors
|
|
* RECOVERING: delay the io until recovery completes
|
|
* NOSYNC: increment pending, just write to the default mirror
|
|
*---------------------------------------------------------------------
|
|
*/
|
|
static void write_callback(unsigned long error, void *context)
|
|
{
|
|
unsigned int i;
|
|
struct bio *bio = context;
|
|
struct mirror_set *ms;
|
|
int should_wake = 0;
|
|
unsigned long flags;
|
|
|
|
ms = bio_get_m(bio)->ms;
|
|
bio_set_m(bio, NULL);
|
|
|
|
/*
|
|
* NOTE: We don't decrement the pending count here,
|
|
* instead it is done by the targets endio function.
|
|
* This way we handle both writes to SYNC and NOSYNC
|
|
* regions with the same code.
|
|
*/
|
|
if (likely(!error)) {
|
|
bio_endio(bio);
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* If the bio is discard, return an error, but do not
|
|
* degrade the array.
|
|
*/
|
|
if (bio_op(bio) == REQ_OP_DISCARD) {
|
|
bio->bi_status = BLK_STS_NOTSUPP;
|
|
bio_endio(bio);
|
|
return;
|
|
}
|
|
|
|
for (i = 0; i < ms->nr_mirrors; i++)
|
|
if (test_bit(i, &error))
|
|
fail_mirror(ms->mirror + i, DM_RAID1_WRITE_ERROR);
|
|
|
|
/*
|
|
* Need to raise event. Since raising
|
|
* events can block, we need to do it in
|
|
* the main thread.
|
|
*/
|
|
spin_lock_irqsave(&ms->lock, flags);
|
|
if (!ms->failures.head)
|
|
should_wake = 1;
|
|
bio_list_add(&ms->failures, bio);
|
|
spin_unlock_irqrestore(&ms->lock, flags);
|
|
if (should_wake)
|
|
wakeup_mirrord(ms);
|
|
}
|
|
|
|
static void do_write(struct mirror_set *ms, struct bio *bio)
|
|
{
|
|
unsigned int i;
|
|
struct dm_io_region io[MAX_NR_MIRRORS], *dest = io;
|
|
struct mirror *m;
|
|
blk_opf_t op_flags = bio->bi_opf & (REQ_FUA | REQ_PREFLUSH);
|
|
struct dm_io_request io_req = {
|
|
.bi_opf = REQ_OP_WRITE | op_flags,
|
|
.mem.type = DM_IO_BIO,
|
|
.mem.ptr.bio = bio,
|
|
.notify.fn = write_callback,
|
|
.notify.context = bio,
|
|
.client = ms->io_client,
|
|
};
|
|
|
|
if (bio_op(bio) == REQ_OP_DISCARD) {
|
|
io_req.bi_opf = REQ_OP_DISCARD | op_flags;
|
|
io_req.mem.type = DM_IO_KMEM;
|
|
io_req.mem.ptr.addr = NULL;
|
|
}
|
|
|
|
for (i = 0, m = ms->mirror; i < ms->nr_mirrors; i++, m++)
|
|
map_region(dest++, m, bio);
|
|
|
|
/*
|
|
* Use default mirror because we only need it to retrieve the reference
|
|
* to the mirror set in write_callback().
|
|
*/
|
|
bio_set_m(bio, get_default_mirror(ms));
|
|
|
|
BUG_ON(dm_io(&io_req, ms->nr_mirrors, io, NULL));
|
|
}
|
|
|
|
static void do_writes(struct mirror_set *ms, struct bio_list *writes)
|
|
{
|
|
int state;
|
|
struct bio *bio;
|
|
struct bio_list sync, nosync, recover, *this_list = NULL;
|
|
struct bio_list requeue;
|
|
struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh);
|
|
region_t region;
|
|
|
|
if (!writes->head)
|
|
return;
|
|
|
|
/*
|
|
* Classify each write.
|
|
*/
|
|
bio_list_init(&sync);
|
|
bio_list_init(&nosync);
|
|
bio_list_init(&recover);
|
|
bio_list_init(&requeue);
|
|
|
|
while ((bio = bio_list_pop(writes))) {
|
|
if ((bio->bi_opf & REQ_PREFLUSH) ||
|
|
(bio_op(bio) == REQ_OP_DISCARD)) {
|
|
bio_list_add(&sync, bio);
|
|
continue;
|
|
}
|
|
|
|
region = dm_rh_bio_to_region(ms->rh, bio);
|
|
|
|
if (log->type->is_remote_recovering &&
|
|
log->type->is_remote_recovering(log, region)) {
|
|
bio_list_add(&requeue, bio);
|
|
continue;
|
|
}
|
|
|
|
state = dm_rh_get_state(ms->rh, region, 1);
|
|
switch (state) {
|
|
case DM_RH_CLEAN:
|
|
case DM_RH_DIRTY:
|
|
this_list = &sync;
|
|
break;
|
|
|
|
case DM_RH_NOSYNC:
|
|
this_list = &nosync;
|
|
break;
|
|
|
|
case DM_RH_RECOVERING:
|
|
this_list = &recover;
|
|
break;
|
|
}
|
|
|
|
bio_list_add(this_list, bio);
|
|
}
|
|
|
|
/*
|
|
* Add bios that are delayed due to remote recovery
|
|
* back on to the write queue
|
|
*/
|
|
if (unlikely(requeue.head)) {
|
|
spin_lock_irq(&ms->lock);
|
|
bio_list_merge(&ms->writes, &requeue);
|
|
spin_unlock_irq(&ms->lock);
|
|
delayed_wake(ms);
|
|
}
|
|
|
|
/*
|
|
* Increment the pending counts for any regions that will
|
|
* be written to (writes to recover regions are going to
|
|
* be delayed).
|
|
*/
|
|
dm_rh_inc_pending(ms->rh, &sync);
|
|
dm_rh_inc_pending(ms->rh, &nosync);
|
|
|
|
/*
|
|
* If the flush fails on a previous call and succeeds here,
|
|
* we must not reset the log_failure variable. We need
|
|
* userspace interaction to do that.
|
|
*/
|
|
ms->log_failure = dm_rh_flush(ms->rh) ? 1 : ms->log_failure;
|
|
|
|
/*
|
|
* Dispatch io.
|
|
*/
|
|
if (unlikely(ms->log_failure) && errors_handled(ms)) {
|
|
spin_lock_irq(&ms->lock);
|
|
bio_list_merge(&ms->failures, &sync);
|
|
spin_unlock_irq(&ms->lock);
|
|
wakeup_mirrord(ms);
|
|
} else
|
|
while ((bio = bio_list_pop(&sync)))
|
|
do_write(ms, bio);
|
|
|
|
while ((bio = bio_list_pop(&recover)))
|
|
dm_rh_delay(ms->rh, bio);
|
|
|
|
while ((bio = bio_list_pop(&nosync))) {
|
|
if (unlikely(ms->leg_failure) && errors_handled(ms) && !keep_log(ms)) {
|
|
spin_lock_irq(&ms->lock);
|
|
bio_list_add(&ms->failures, bio);
|
|
spin_unlock_irq(&ms->lock);
|
|
wakeup_mirrord(ms);
|
|
} else {
|
|
map_bio(get_default_mirror(ms), bio);
|
|
submit_bio_noacct(bio);
|
|
}
|
|
}
|
|
}
|
|
|
|
static void do_failures(struct mirror_set *ms, struct bio_list *failures)
|
|
{
|
|
struct bio *bio;
|
|
|
|
if (likely(!failures->head))
|
|
return;
|
|
|
|
/*
|
|
* If the log has failed, unattempted writes are being
|
|
* put on the holds list. We can't issue those writes
|
|
* until a log has been marked, so we must store them.
|
|
*
|
|
* If a 'noflush' suspend is in progress, we can requeue
|
|
* the I/O's to the core. This give userspace a chance
|
|
* to reconfigure the mirror, at which point the core
|
|
* will reissue the writes. If the 'noflush' flag is
|
|
* not set, we have no choice but to return errors.
|
|
*
|
|
* Some writes on the failures list may have been
|
|
* submitted before the log failure and represent a
|
|
* failure to write to one of the devices. It is ok
|
|
* for us to treat them the same and requeue them
|
|
* as well.
|
|
*/
|
|
while ((bio = bio_list_pop(failures))) {
|
|
if (!ms->log_failure) {
|
|
ms->in_sync = 0;
|
|
dm_rh_mark_nosync(ms->rh, bio);
|
|
}
|
|
|
|
/*
|
|
* If all the legs are dead, fail the I/O.
|
|
* If the device has failed and keep_log is enabled,
|
|
* fail the I/O.
|
|
*
|
|
* If we have been told to handle errors, and keep_log
|
|
* isn't enabled, hold the bio and wait for userspace to
|
|
* deal with the problem.
|
|
*
|
|
* Otherwise pretend that the I/O succeeded. (This would
|
|
* be wrong if the failed leg returned after reboot and
|
|
* got replicated back to the good legs.)
|
|
*/
|
|
if (unlikely(!get_valid_mirror(ms) || (keep_log(ms) && ms->log_failure)))
|
|
bio_io_error(bio);
|
|
else if (errors_handled(ms) && !keep_log(ms))
|
|
hold_bio(ms, bio);
|
|
else
|
|
bio_endio(bio);
|
|
}
|
|
}
|
|
|
|
static void trigger_event(struct work_struct *work)
|
|
{
|
|
struct mirror_set *ms =
|
|
container_of(work, struct mirror_set, trigger_event);
|
|
|
|
dm_table_event(ms->ti->table);
|
|
}
|
|
|
|
/*
|
|
*---------------------------------------------------------------
|
|
* kmirrord
|
|
*---------------------------------------------------------------
|
|
*/
|
|
static void do_mirror(struct work_struct *work)
|
|
{
|
|
struct mirror_set *ms = container_of(work, struct mirror_set,
|
|
kmirrord_work);
|
|
struct bio_list reads, writes, failures;
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&ms->lock, flags);
|
|
reads = ms->reads;
|
|
writes = ms->writes;
|
|
failures = ms->failures;
|
|
bio_list_init(&ms->reads);
|
|
bio_list_init(&ms->writes);
|
|
bio_list_init(&ms->failures);
|
|
spin_unlock_irqrestore(&ms->lock, flags);
|
|
|
|
dm_rh_update_states(ms->rh, errors_handled(ms));
|
|
do_recovery(ms);
|
|
do_reads(ms, &reads);
|
|
do_writes(ms, &writes);
|
|
do_failures(ms, &failures);
|
|
}
|
|
|
|
/*
|
|
*---------------------------------------------------------------
|
|
* Target functions
|
|
*---------------------------------------------------------------
|
|
*/
|
|
static struct mirror_set *alloc_context(unsigned int nr_mirrors,
|
|
uint32_t region_size,
|
|
struct dm_target *ti,
|
|
struct dm_dirty_log *dl)
|
|
{
|
|
struct mirror_set *ms =
|
|
kzalloc(struct_size(ms, mirror, nr_mirrors), GFP_KERNEL);
|
|
|
|
if (!ms) {
|
|
ti->error = "Cannot allocate mirror context";
|
|
return NULL;
|
|
}
|
|
|
|
spin_lock_init(&ms->lock);
|
|
bio_list_init(&ms->reads);
|
|
bio_list_init(&ms->writes);
|
|
bio_list_init(&ms->failures);
|
|
bio_list_init(&ms->holds);
|
|
|
|
ms->ti = ti;
|
|
ms->nr_mirrors = nr_mirrors;
|
|
ms->nr_regions = dm_sector_div_up(ti->len, region_size);
|
|
ms->in_sync = 0;
|
|
ms->log_failure = 0;
|
|
ms->leg_failure = 0;
|
|
atomic_set(&ms->suspend, 0);
|
|
atomic_set(&ms->default_mirror, DEFAULT_MIRROR);
|
|
|
|
ms->io_client = dm_io_client_create();
|
|
if (IS_ERR(ms->io_client)) {
|
|
ti->error = "Error creating dm_io client";
|
|
kfree(ms);
|
|
return NULL;
|
|
}
|
|
|
|
ms->rh = dm_region_hash_create(ms, dispatch_bios, wakeup_mirrord,
|
|
wakeup_all_recovery_waiters,
|
|
ms->ti->begin, MAX_RECOVERY,
|
|
dl, region_size, ms->nr_regions);
|
|
if (IS_ERR(ms->rh)) {
|
|
ti->error = "Error creating dirty region hash";
|
|
dm_io_client_destroy(ms->io_client);
|
|
kfree(ms);
|
|
return NULL;
|
|
}
|
|
|
|
return ms;
|
|
}
|
|
|
|
static void free_context(struct mirror_set *ms, struct dm_target *ti,
|
|
unsigned int m)
|
|
{
|
|
while (m--)
|
|
dm_put_device(ti, ms->mirror[m].dev);
|
|
|
|
dm_io_client_destroy(ms->io_client);
|
|
dm_region_hash_destroy(ms->rh);
|
|
kfree(ms);
|
|
}
|
|
|
|
static int get_mirror(struct mirror_set *ms, struct dm_target *ti,
|
|
unsigned int mirror, char **argv)
|
|
{
|
|
unsigned long long offset;
|
|
char dummy;
|
|
int ret;
|
|
|
|
if (sscanf(argv[1], "%llu%c", &offset, &dummy) != 1 ||
|
|
offset != (sector_t)offset) {
|
|
ti->error = "Invalid offset";
|
|
return -EINVAL;
|
|
}
|
|
|
|
ret = dm_get_device(ti, argv[0], dm_table_get_mode(ti->table),
|
|
&ms->mirror[mirror].dev);
|
|
if (ret) {
|
|
ti->error = "Device lookup failure";
|
|
return ret;
|
|
}
|
|
|
|
ms->mirror[mirror].ms = ms;
|
|
atomic_set(&(ms->mirror[mirror].error_count), 0);
|
|
ms->mirror[mirror].error_type = 0;
|
|
ms->mirror[mirror].offset = offset;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Create dirty log: log_type #log_params <log_params>
|
|
*/
|
|
static struct dm_dirty_log *create_dirty_log(struct dm_target *ti,
|
|
unsigned int argc, char **argv,
|
|
unsigned int *args_used)
|
|
{
|
|
unsigned int param_count;
|
|
struct dm_dirty_log *dl;
|
|
char dummy;
|
|
|
|
if (argc < 2) {
|
|
ti->error = "Insufficient mirror log arguments";
|
|
return NULL;
|
|
}
|
|
|
|
if (sscanf(argv[1], "%u%c", ¶m_count, &dummy) != 1) {
|
|
ti->error = "Invalid mirror log argument count";
|
|
return NULL;
|
|
}
|
|
|
|
*args_used = 2 + param_count;
|
|
|
|
if (argc < *args_used) {
|
|
ti->error = "Insufficient mirror log arguments";
|
|
return NULL;
|
|
}
|
|
|
|
dl = dm_dirty_log_create(argv[0], ti, mirror_flush, param_count,
|
|
argv + 2);
|
|
if (!dl) {
|
|
ti->error = "Error creating mirror dirty log";
|
|
return NULL;
|
|
}
|
|
|
|
return dl;
|
|
}
|
|
|
|
static int parse_features(struct mirror_set *ms, unsigned int argc, char **argv,
|
|
unsigned int *args_used)
|
|
{
|
|
unsigned int num_features;
|
|
struct dm_target *ti = ms->ti;
|
|
char dummy;
|
|
int i;
|
|
|
|
*args_used = 0;
|
|
|
|
if (!argc)
|
|
return 0;
|
|
|
|
if (sscanf(argv[0], "%u%c", &num_features, &dummy) != 1) {
|
|
ti->error = "Invalid number of features";
|
|
return -EINVAL;
|
|
}
|
|
|
|
argc--;
|
|
argv++;
|
|
(*args_used)++;
|
|
|
|
if (num_features > argc) {
|
|
ti->error = "Not enough arguments to support feature count";
|
|
return -EINVAL;
|
|
}
|
|
|
|
for (i = 0; i < num_features; i++) {
|
|
if (!strcmp("handle_errors", argv[0]))
|
|
ms->features |= DM_RAID1_HANDLE_ERRORS;
|
|
else if (!strcmp("keep_log", argv[0]))
|
|
ms->features |= DM_RAID1_KEEP_LOG;
|
|
else {
|
|
ti->error = "Unrecognised feature requested";
|
|
return -EINVAL;
|
|
}
|
|
|
|
argc--;
|
|
argv++;
|
|
(*args_used)++;
|
|
}
|
|
if (!errors_handled(ms) && keep_log(ms)) {
|
|
ti->error = "keep_log feature requires the handle_errors feature";
|
|
return -EINVAL;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Construct a mirror mapping:
|
|
*
|
|
* log_type #log_params <log_params>
|
|
* #mirrors [mirror_path offset]{2,}
|
|
* [#features <features>]
|
|
*
|
|
* log_type is "core" or "disk"
|
|
* #log_params is between 1 and 3
|
|
*
|
|
* If present, supported features are "handle_errors" and "keep_log".
|
|
*/
|
|
static int mirror_ctr(struct dm_target *ti, unsigned int argc, char **argv)
|
|
{
|
|
int r;
|
|
unsigned int nr_mirrors, m, args_used;
|
|
struct mirror_set *ms;
|
|
struct dm_dirty_log *dl;
|
|
char dummy;
|
|
|
|
dl = create_dirty_log(ti, argc, argv, &args_used);
|
|
if (!dl)
|
|
return -EINVAL;
|
|
|
|
argv += args_used;
|
|
argc -= args_used;
|
|
|
|
if (!argc || sscanf(argv[0], "%u%c", &nr_mirrors, &dummy) != 1 ||
|
|
nr_mirrors < 2 || nr_mirrors > MAX_NR_MIRRORS) {
|
|
ti->error = "Invalid number of mirrors";
|
|
dm_dirty_log_destroy(dl);
|
|
return -EINVAL;
|
|
}
|
|
|
|
argv++, argc--;
|
|
|
|
if (argc < nr_mirrors * 2) {
|
|
ti->error = "Too few mirror arguments";
|
|
dm_dirty_log_destroy(dl);
|
|
return -EINVAL;
|
|
}
|
|
|
|
ms = alloc_context(nr_mirrors, dl->type->get_region_size(dl), ti, dl);
|
|
if (!ms) {
|
|
dm_dirty_log_destroy(dl);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
/* Get the mirror parameter sets */
|
|
for (m = 0; m < nr_mirrors; m++) {
|
|
r = get_mirror(ms, ti, m, argv);
|
|
if (r) {
|
|
free_context(ms, ti, m);
|
|
return r;
|
|
}
|
|
argv += 2;
|
|
argc -= 2;
|
|
}
|
|
|
|
ti->private = ms;
|
|
|
|
r = dm_set_target_max_io_len(ti, dm_rh_get_region_size(ms->rh));
|
|
if (r)
|
|
goto err_free_context;
|
|
|
|
ti->num_flush_bios = 1;
|
|
ti->num_discard_bios = 1;
|
|
ti->per_io_data_size = sizeof(struct dm_raid1_bio_record);
|
|
|
|
ms->kmirrord_wq = alloc_workqueue("kmirrord", WQ_MEM_RECLAIM, 0);
|
|
if (!ms->kmirrord_wq) {
|
|
DMERR("couldn't start kmirrord");
|
|
r = -ENOMEM;
|
|
goto err_free_context;
|
|
}
|
|
INIT_WORK(&ms->kmirrord_work, do_mirror);
|
|
timer_setup(&ms->timer, delayed_wake_fn, 0);
|
|
ms->timer_pending = 0;
|
|
INIT_WORK(&ms->trigger_event, trigger_event);
|
|
|
|
r = parse_features(ms, argc, argv, &args_used);
|
|
if (r)
|
|
goto err_destroy_wq;
|
|
|
|
argv += args_used;
|
|
argc -= args_used;
|
|
|
|
/*
|
|
* Any read-balancing addition depends on the
|
|
* DM_RAID1_HANDLE_ERRORS flag being present.
|
|
* This is because the decision to balance depends
|
|
* on the sync state of a region. If the above
|
|
* flag is not present, we ignore errors; and
|
|
* the sync state may be inaccurate.
|
|
*/
|
|
|
|
if (argc) {
|
|
ti->error = "Too many mirror arguments";
|
|
r = -EINVAL;
|
|
goto err_destroy_wq;
|
|
}
|
|
|
|
ms->kcopyd_client = dm_kcopyd_client_create(&dm_kcopyd_throttle);
|
|
if (IS_ERR(ms->kcopyd_client)) {
|
|
r = PTR_ERR(ms->kcopyd_client);
|
|
goto err_destroy_wq;
|
|
}
|
|
|
|
wakeup_mirrord(ms);
|
|
return 0;
|
|
|
|
err_destroy_wq:
|
|
destroy_workqueue(ms->kmirrord_wq);
|
|
err_free_context:
|
|
free_context(ms, ti, ms->nr_mirrors);
|
|
return r;
|
|
}
|
|
|
|
static void mirror_dtr(struct dm_target *ti)
|
|
{
|
|
struct mirror_set *ms = ti->private;
|
|
|
|
del_timer_sync(&ms->timer);
|
|
flush_workqueue(ms->kmirrord_wq);
|
|
flush_work(&ms->trigger_event);
|
|
dm_kcopyd_client_destroy(ms->kcopyd_client);
|
|
destroy_workqueue(ms->kmirrord_wq);
|
|
free_context(ms, ti, ms->nr_mirrors);
|
|
}
|
|
|
|
/*
|
|
* Mirror mapping function
|
|
*/
|
|
static int mirror_map(struct dm_target *ti, struct bio *bio)
|
|
{
|
|
int r, rw = bio_data_dir(bio);
|
|
struct mirror *m;
|
|
struct mirror_set *ms = ti->private;
|
|
struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh);
|
|
struct dm_raid1_bio_record *bio_record =
|
|
dm_per_bio_data(bio, sizeof(struct dm_raid1_bio_record));
|
|
|
|
bio_record->details.bi_bdev = NULL;
|
|
|
|
if (rw == WRITE) {
|
|
/* Save region for mirror_end_io() handler */
|
|
bio_record->write_region = dm_rh_bio_to_region(ms->rh, bio);
|
|
queue_bio(ms, bio, rw);
|
|
return DM_MAPIO_SUBMITTED;
|
|
}
|
|
|
|
r = log->type->in_sync(log, dm_rh_bio_to_region(ms->rh, bio), 0);
|
|
if (r < 0 && r != -EWOULDBLOCK)
|
|
return DM_MAPIO_KILL;
|
|
|
|
/*
|
|
* If region is not in-sync queue the bio.
|
|
*/
|
|
if (!r || (r == -EWOULDBLOCK)) {
|
|
if (bio->bi_opf & REQ_RAHEAD)
|
|
return DM_MAPIO_KILL;
|
|
|
|
queue_bio(ms, bio, rw);
|
|
return DM_MAPIO_SUBMITTED;
|
|
}
|
|
|
|
/*
|
|
* The region is in-sync and we can perform reads directly.
|
|
* Store enough information so we can retry if it fails.
|
|
*/
|
|
m = choose_mirror(ms, bio->bi_iter.bi_sector);
|
|
if (unlikely(!m))
|
|
return DM_MAPIO_KILL;
|
|
|
|
dm_bio_record(&bio_record->details, bio);
|
|
bio_record->m = m;
|
|
|
|
map_bio(m, bio);
|
|
|
|
return DM_MAPIO_REMAPPED;
|
|
}
|
|
|
|
static int mirror_end_io(struct dm_target *ti, struct bio *bio,
|
|
blk_status_t *error)
|
|
{
|
|
int rw = bio_data_dir(bio);
|
|
struct mirror_set *ms = ti->private;
|
|
struct mirror *m = NULL;
|
|
struct dm_bio_details *bd = NULL;
|
|
struct dm_raid1_bio_record *bio_record =
|
|
dm_per_bio_data(bio, sizeof(struct dm_raid1_bio_record));
|
|
|
|
/*
|
|
* We need to dec pending if this was a write.
|
|
*/
|
|
if (rw == WRITE) {
|
|
if (!(bio->bi_opf & REQ_PREFLUSH) &&
|
|
bio_op(bio) != REQ_OP_DISCARD)
|
|
dm_rh_dec(ms->rh, bio_record->write_region);
|
|
return DM_ENDIO_DONE;
|
|
}
|
|
|
|
if (*error == BLK_STS_NOTSUPP)
|
|
goto out;
|
|
|
|
if (bio->bi_opf & REQ_RAHEAD)
|
|
goto out;
|
|
|
|
if (unlikely(*error)) {
|
|
if (!bio_record->details.bi_bdev) {
|
|
/*
|
|
* There wasn't enough memory to record necessary
|
|
* information for a retry or there was no other
|
|
* mirror in-sync.
|
|
*/
|
|
DMERR_LIMIT("Mirror read failed.");
|
|
return DM_ENDIO_DONE;
|
|
}
|
|
|
|
m = bio_record->m;
|
|
|
|
DMERR("Mirror read failed from %s. Trying alternative device.",
|
|
m->dev->name);
|
|
|
|
fail_mirror(m, DM_RAID1_READ_ERROR);
|
|
|
|
/*
|
|
* A failed read is requeued for another attempt using an intact
|
|
* mirror.
|
|
*/
|
|
if (default_ok(m) || mirror_available(ms, bio)) {
|
|
bd = &bio_record->details;
|
|
|
|
dm_bio_restore(bd, bio);
|
|
bio_record->details.bi_bdev = NULL;
|
|
bio->bi_status = 0;
|
|
|
|
queue_bio(ms, bio, rw);
|
|
return DM_ENDIO_INCOMPLETE;
|
|
}
|
|
DMERR("All replicated volumes dead, failing I/O");
|
|
}
|
|
|
|
out:
|
|
bio_record->details.bi_bdev = NULL;
|
|
|
|
return DM_ENDIO_DONE;
|
|
}
|
|
|
|
static void mirror_presuspend(struct dm_target *ti)
|
|
{
|
|
struct mirror_set *ms = ti->private;
|
|
struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh);
|
|
|
|
struct bio_list holds;
|
|
struct bio *bio;
|
|
|
|
atomic_set(&ms->suspend, 1);
|
|
|
|
/*
|
|
* Process bios in the hold list to start recovery waiting
|
|
* for bios in the hold list. After the process, no bio has
|
|
* a chance to be added in the hold list because ms->suspend
|
|
* is set.
|
|
*/
|
|
spin_lock_irq(&ms->lock);
|
|
holds = ms->holds;
|
|
bio_list_init(&ms->holds);
|
|
spin_unlock_irq(&ms->lock);
|
|
|
|
while ((bio = bio_list_pop(&holds)))
|
|
hold_bio(ms, bio);
|
|
|
|
/*
|
|
* We must finish up all the work that we've
|
|
* generated (i.e. recovery work).
|
|
*/
|
|
dm_rh_stop_recovery(ms->rh);
|
|
|
|
wait_event(_kmirrord_recovery_stopped,
|
|
!dm_rh_recovery_in_flight(ms->rh));
|
|
|
|
if (log->type->presuspend && log->type->presuspend(log))
|
|
/* FIXME: need better error handling */
|
|
DMWARN("log presuspend failed");
|
|
|
|
/*
|
|
* Now that recovery is complete/stopped and the
|
|
* delayed bios are queued, we need to wait for
|
|
* the worker thread to complete. This way,
|
|
* we know that all of our I/O has been pushed.
|
|
*/
|
|
flush_workqueue(ms->kmirrord_wq);
|
|
}
|
|
|
|
static void mirror_postsuspend(struct dm_target *ti)
|
|
{
|
|
struct mirror_set *ms = ti->private;
|
|
struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh);
|
|
|
|
if (log->type->postsuspend && log->type->postsuspend(log))
|
|
/* FIXME: need better error handling */
|
|
DMWARN("log postsuspend failed");
|
|
}
|
|
|
|
static void mirror_resume(struct dm_target *ti)
|
|
{
|
|
struct mirror_set *ms = ti->private;
|
|
struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh);
|
|
|
|
atomic_set(&ms->suspend, 0);
|
|
if (log->type->resume && log->type->resume(log))
|
|
/* FIXME: need better error handling */
|
|
DMWARN("log resume failed");
|
|
dm_rh_start_recovery(ms->rh);
|
|
}
|
|
|
|
/*
|
|
* device_status_char
|
|
* @m: mirror device/leg we want the status of
|
|
*
|
|
* We return one character representing the most severe error
|
|
* we have encountered.
|
|
* A => Alive - No failures
|
|
* D => Dead - A write failure occurred leaving mirror out-of-sync
|
|
* S => Sync - A sychronization failure occurred, mirror out-of-sync
|
|
* R => Read - A read failure occurred, mirror data unaffected
|
|
*
|
|
* Returns: <char>
|
|
*/
|
|
static char device_status_char(struct mirror *m)
|
|
{
|
|
if (!atomic_read(&(m->error_count)))
|
|
return 'A';
|
|
|
|
return (test_bit(DM_RAID1_FLUSH_ERROR, &(m->error_type))) ? 'F' :
|
|
(test_bit(DM_RAID1_WRITE_ERROR, &(m->error_type))) ? 'D' :
|
|
(test_bit(DM_RAID1_SYNC_ERROR, &(m->error_type))) ? 'S' :
|
|
(test_bit(DM_RAID1_READ_ERROR, &(m->error_type))) ? 'R' : 'U';
|
|
}
|
|
|
|
|
|
static void mirror_status(struct dm_target *ti, status_type_t type,
|
|
unsigned int status_flags, char *result, unsigned int maxlen)
|
|
{
|
|
unsigned int m, sz = 0;
|
|
int num_feature_args = 0;
|
|
struct mirror_set *ms = ti->private;
|
|
struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh);
|
|
char buffer[MAX_NR_MIRRORS + 1];
|
|
|
|
switch (type) {
|
|
case STATUSTYPE_INFO:
|
|
DMEMIT("%d ", ms->nr_mirrors);
|
|
for (m = 0; m < ms->nr_mirrors; m++) {
|
|
DMEMIT("%s ", ms->mirror[m].dev->name);
|
|
buffer[m] = device_status_char(&(ms->mirror[m]));
|
|
}
|
|
buffer[m] = '\0';
|
|
|
|
DMEMIT("%llu/%llu 1 %s ",
|
|
(unsigned long long)log->type->get_sync_count(log),
|
|
(unsigned long long)ms->nr_regions, buffer);
|
|
|
|
sz += log->type->status(log, type, result+sz, maxlen-sz);
|
|
|
|
break;
|
|
|
|
case STATUSTYPE_TABLE:
|
|
sz = log->type->status(log, type, result, maxlen);
|
|
|
|
DMEMIT("%d", ms->nr_mirrors);
|
|
for (m = 0; m < ms->nr_mirrors; m++)
|
|
DMEMIT(" %s %llu", ms->mirror[m].dev->name,
|
|
(unsigned long long)ms->mirror[m].offset);
|
|
|
|
num_feature_args += !!errors_handled(ms);
|
|
num_feature_args += !!keep_log(ms);
|
|
if (num_feature_args) {
|
|
DMEMIT(" %d", num_feature_args);
|
|
if (errors_handled(ms))
|
|
DMEMIT(" handle_errors");
|
|
if (keep_log(ms))
|
|
DMEMIT(" keep_log");
|
|
}
|
|
|
|
break;
|
|
|
|
case STATUSTYPE_IMA:
|
|
DMEMIT_TARGET_NAME_VERSION(ti->type);
|
|
DMEMIT(",nr_mirrors=%d", ms->nr_mirrors);
|
|
for (m = 0; m < ms->nr_mirrors; m++) {
|
|
DMEMIT(",mirror_device_%d=%s", m, ms->mirror[m].dev->name);
|
|
DMEMIT(",mirror_device_%d_status=%c",
|
|
m, device_status_char(&(ms->mirror[m])));
|
|
}
|
|
|
|
DMEMIT(",handle_errors=%c", errors_handled(ms) ? 'y' : 'n');
|
|
DMEMIT(",keep_log=%c", keep_log(ms) ? 'y' : 'n');
|
|
|
|
DMEMIT(",log_type_status=");
|
|
sz += log->type->status(log, type, result+sz, maxlen-sz);
|
|
DMEMIT(";");
|
|
break;
|
|
}
|
|
}
|
|
|
|
static int mirror_iterate_devices(struct dm_target *ti,
|
|
iterate_devices_callout_fn fn, void *data)
|
|
{
|
|
struct mirror_set *ms = ti->private;
|
|
int ret = 0;
|
|
unsigned int i;
|
|
|
|
for (i = 0; !ret && i < ms->nr_mirrors; i++)
|
|
ret = fn(ti, ms->mirror[i].dev,
|
|
ms->mirror[i].offset, ti->len, data);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static struct target_type mirror_target = {
|
|
.name = "mirror",
|
|
.version = {1, 14, 0},
|
|
.module = THIS_MODULE,
|
|
.ctr = mirror_ctr,
|
|
.dtr = mirror_dtr,
|
|
.map = mirror_map,
|
|
.end_io = mirror_end_io,
|
|
.presuspend = mirror_presuspend,
|
|
.postsuspend = mirror_postsuspend,
|
|
.resume = mirror_resume,
|
|
.status = mirror_status,
|
|
.iterate_devices = mirror_iterate_devices,
|
|
};
|
|
|
|
static int __init dm_mirror_init(void)
|
|
{
|
|
int r;
|
|
|
|
dm_raid1_wq = alloc_workqueue("dm_raid1_wq", 0, 0);
|
|
if (!dm_raid1_wq) {
|
|
DMERR("Failed to alloc workqueue");
|
|
return -ENOMEM;
|
|
}
|
|
|
|
r = dm_register_target(&mirror_target);
|
|
if (r < 0) {
|
|
destroy_workqueue(dm_raid1_wq);
|
|
return r;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void __exit dm_mirror_exit(void)
|
|
{
|
|
destroy_workqueue(dm_raid1_wq);
|
|
dm_unregister_target(&mirror_target);
|
|
}
|
|
|
|
/* Module hooks */
|
|
module_init(dm_mirror_init);
|
|
module_exit(dm_mirror_exit);
|
|
|
|
MODULE_DESCRIPTION(DM_NAME " mirror target");
|
|
MODULE_AUTHOR("Joe Thornber");
|
|
MODULE_LICENSE("GPL");
|