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Diffstat (limited to 'drivers/md/raid5-cache.c')
-rw-r--r--drivers/md/raid5-cache.c706
1 files changed, 552 insertions, 154 deletions
diff --git a/drivers/md/raid5-cache.c b/drivers/md/raid5-cache.c
index 302dea3296ba..bfa1e907c472 100644
--- a/drivers/md/raid5-cache.c
+++ b/drivers/md/raid5-cache.c
@@ -20,15 +20,18 @@
#include <linux/crc32c.h>
#include <linux/random.h>
#include <linux/kthread.h>
+#include <linux/types.h>
#include "md.h"
#include "raid5.h"
#include "bitmap.h"
+#include "raid5-log.h"
/*
* metadata/data stored in disk with 4k size unit (a block) regardless
* underneath hardware sector size. only works with PAGE_SIZE == 4096
*/
#define BLOCK_SECTORS (8)
+#define BLOCK_SECTOR_SHIFT (3)
/*
* log->max_free_space is min(1/4 disk size, 10G reclaimable space).
@@ -42,7 +45,7 @@
/* wake up reclaim thread periodically */
#define R5C_RECLAIM_WAKEUP_INTERVAL (30 * HZ)
/* start flush with these full stripes */
-#define R5C_FULL_STRIPE_FLUSH_BATCH 256
+#define R5C_FULL_STRIPE_FLUSH_BATCH(conf) (conf->max_nr_stripes / 4)
/* reclaim stripes in groups */
#define R5C_RECLAIM_STRIPE_GROUP (NR_STRIPE_HASH_LOCKS * 2)
@@ -52,16 +55,6 @@
*/
#define R5L_POOL_SIZE 4
-/*
- * r5c journal modes of the array: write-back or write-through.
- * write-through mode has identical behavior as existing log only
- * implementation.
- */
-enum r5c_journal_mode {
- R5C_JOURNAL_MODE_WRITE_THROUGH = 0,
- R5C_JOURNAL_MODE_WRITE_BACK = 1,
-};
-
static char *r5c_journal_mode_str[] = {"write-through",
"write-back"};
/*
@@ -164,9 +157,60 @@ struct r5l_log {
struct work_struct deferred_io_work;
/* to disable write back during in degraded mode */
struct work_struct disable_writeback_work;
+
+ /* to for chunk_aligned_read in writeback mode, details below */
+ spinlock_t tree_lock;
+ struct radix_tree_root big_stripe_tree;
};
/*
+ * Enable chunk_aligned_read() with write back cache.
+ *
+ * Each chunk may contain more than one stripe (for example, a 256kB
+ * chunk contains 64 4kB-page, so this chunk contain 64 stripes). For
+ * chunk_aligned_read, these stripes are grouped into one "big_stripe".
+ * For each big_stripe, we count how many stripes of this big_stripe
+ * are in the write back cache. These data are tracked in a radix tree
+ * (big_stripe_tree). We use radix_tree item pointer as the counter.
+ * r5c_tree_index() is used to calculate keys for the radix tree.
+ *
+ * chunk_aligned_read() calls r5c_big_stripe_cached() to look up
+ * big_stripe of each chunk in the tree. If this big_stripe is in the
+ * tree, chunk_aligned_read() aborts. This look up is protected by
+ * rcu_read_lock().
+ *
+ * It is necessary to remember whether a stripe is counted in
+ * big_stripe_tree. Instead of adding new flag, we reuses existing flags:
+ * STRIPE_R5C_PARTIAL_STRIPE and STRIPE_R5C_FULL_STRIPE. If either of these
+ * two flags are set, the stripe is counted in big_stripe_tree. This
+ * requires moving set_bit(STRIPE_R5C_PARTIAL_STRIPE) to
+ * r5c_try_caching_write(); and moving clear_bit of
+ * STRIPE_R5C_PARTIAL_STRIPE and STRIPE_R5C_FULL_STRIPE to
+ * r5c_finish_stripe_write_out().
+ */
+
+/*
+ * radix tree requests lowest 2 bits of data pointer to be 2b'00.
+ * So it is necessary to left shift the counter by 2 bits before using it
+ * as data pointer of the tree.
+ */
+#define R5C_RADIX_COUNT_SHIFT 2
+
+/*
+ * calculate key for big_stripe_tree
+ *
+ * sect: align_bi->bi_iter.bi_sector or sh->sector
+ */
+static inline sector_t r5c_tree_index(struct r5conf *conf,
+ sector_t sect)
+{
+ sector_t offset;
+
+ offset = sector_div(sect, conf->chunk_sectors);
+ return sect;
+}
+
+/*
* an IO range starts from a meta data block and end at the next meta data
* block. The io unit's the meta data block tracks data/parity followed it. io
* unit is written to log disk with normal write, as we always flush log disk
@@ -255,8 +299,7 @@ static void __r5l_set_io_unit_state(struct r5l_io_unit *io,
}
static void
-r5c_return_dev_pending_writes(struct r5conf *conf, struct r5dev *dev,
- struct bio_list *return_bi)
+r5c_return_dev_pending_writes(struct r5conf *conf, struct r5dev *dev)
{
struct bio *wbi, *wbi2;
@@ -265,24 +308,21 @@ r5c_return_dev_pending_writes(struct r5conf *conf, struct r5dev *dev,
while (wbi && wbi->bi_iter.bi_sector <
dev->sector + STRIPE_SECTORS) {
wbi2 = r5_next_bio(wbi, dev->sector);
- if (!raid5_dec_bi_active_stripes(wbi)) {
- md_write_end(conf->mddev);
- bio_list_add(return_bi, wbi);
- }
+ md_write_end(conf->mddev);
+ bio_endio(wbi);
wbi = wbi2;
}
}
void r5c_handle_cached_data_endio(struct r5conf *conf,
- struct stripe_head *sh, int disks, struct bio_list *return_bi)
+ struct stripe_head *sh, int disks)
{
int i;
for (i = sh->disks; i--; ) {
if (sh->dev[i].written) {
set_bit(R5_UPTODATE, &sh->dev[i].flags);
- r5c_return_dev_pending_writes(conf, &sh->dev[i],
- return_bi);
+ r5c_return_dev_pending_writes(conf, &sh->dev[i]);
bitmap_endwrite(conf->mddev->bitmap, sh->sector,
STRIPE_SECTORS,
!test_bit(STRIPE_DEGRADED, &sh->state),
@@ -291,6 +331,8 @@ void r5c_handle_cached_data_endio(struct r5conf *conf,
}
}
+void r5l_wake_reclaim(struct r5l_log *log, sector_t space);
+
/* Check whether we should flush some stripes to free up stripe cache */
void r5c_check_stripe_cache_usage(struct r5conf *conf)
{
@@ -329,7 +371,7 @@ void r5c_check_cached_full_stripe(struct r5conf *conf)
* or a full stripe (chunk size / 4k stripes).
*/
if (atomic_read(&conf->r5c_cached_full_stripes) >=
- min(R5C_FULL_STRIPE_FLUSH_BATCH,
+ min(R5C_FULL_STRIPE_FLUSH_BATCH(conf),
conf->chunk_sectors >> STRIPE_SHIFT))
r5l_wake_reclaim(conf->log, 0);
}
@@ -337,17 +379,30 @@ void r5c_check_cached_full_stripe(struct r5conf *conf)
/*
* Total log space (in sectors) needed to flush all data in cache
*
- * Currently, writing-out phase automatically includes all pending writes
- * to the same sector. So the reclaim of each stripe takes up to
- * (conf->raid_disks + 1) pages of log space.
+ * To avoid deadlock due to log space, it is necessary to reserve log
+ * space to flush critical stripes (stripes that occupying log space near
+ * last_checkpoint). This function helps check how much log space is
+ * required to flush all cached stripes.
+ *
+ * To reduce log space requirements, two mechanisms are used to give cache
+ * flush higher priorities:
+ * 1. In handle_stripe_dirtying() and schedule_reconstruction(),
+ * stripes ALREADY in journal can be flushed w/o pending writes;
+ * 2. In r5l_write_stripe() and r5c_cache_data(), stripes NOT in journal
+ * can be delayed (r5l_add_no_space_stripe).
*
- * To totally avoid deadlock due to log space, the code reserves
- * (conf->raid_disks + 1) pages for each stripe in cache, which is not
- * necessary in most cases.
+ * In cache flush, the stripe goes through 1 and then 2. For a stripe that
+ * already passed 1, flushing it requires at most (conf->max_degraded + 1)
+ * pages of journal space. For stripes that has not passed 1, flushing it
+ * requires (conf->raid_disks + 1) pages of journal space. There are at
+ * most (conf->group_cnt + 1) stripe that passed 1. So total journal space
+ * required to flush all cached stripes (in pages) is:
*
- * To improve this, we will need writing-out phase to be able to NOT include
- * pending writes, which will reduce the requirement to
- * (conf->max_degraded + 1) pages per stripe in cache.
+ * (stripe_in_journal_count - group_cnt - 1) * (max_degraded + 1) +
+ * (group_cnt + 1) * (raid_disks + 1)
+ * or
+ * (stripe_in_journal_count) * (max_degraded + 1) +
+ * (group_cnt + 1) * (raid_disks - max_degraded)
*/
static sector_t r5c_log_required_to_flush_cache(struct r5conf *conf)
{
@@ -356,8 +411,9 @@ static sector_t r5c_log_required_to_flush_cache(struct r5conf *conf)
if (!r5c_is_writeback(log))
return 0;
- return BLOCK_SECTORS * (conf->raid_disks + 1) *
- atomic_read(&log->stripe_in_journal_count);
+ return BLOCK_SECTORS *
+ ((conf->max_degraded + 1) * atomic_read(&log->stripe_in_journal_count) +
+ (conf->raid_disks - conf->max_degraded) * (conf->group_cnt + 1));
}
/*
@@ -412,16 +468,6 @@ void r5c_make_stripe_write_out(struct stripe_head *sh)
if (!test_and_set_bit(STRIPE_PREREAD_ACTIVE, &sh->state))
atomic_inc(&conf->preread_active_stripes);
-
- if (test_and_clear_bit(STRIPE_R5C_PARTIAL_STRIPE, &sh->state)) {
- BUG_ON(atomic_read(&conf->r5c_cached_partial_stripes) == 0);
- atomic_dec(&conf->r5c_cached_partial_stripes);
- }
-
- if (test_and_clear_bit(STRIPE_R5C_FULL_STRIPE, &sh->state)) {
- BUG_ON(atomic_read(&conf->r5c_cached_full_stripes) == 0);
- atomic_dec(&conf->r5c_cached_full_stripes);
- }
}
static void r5c_handle_data_cached(struct stripe_head *sh)
@@ -526,7 +572,7 @@ static void r5l_log_endio(struct bio *bio)
struct r5l_log *log = io->log;
unsigned long flags;
- if (bio->bi_error)
+ if (bio->bi_status)
md_error(log->rdev->mddev, log->rdev);
bio_put(bio);
@@ -534,7 +580,7 @@ static void r5l_log_endio(struct bio *bio)
spin_lock_irqsave(&log->io_list_lock, flags);
__r5l_set_io_unit_state(io, IO_UNIT_IO_END);
- if (log->need_cache_flush)
+ if (log->need_cache_flush && !list_empty(&io->stripe_list))
r5l_move_to_end_ios(log);
else
r5l_log_run_stripes(log);
@@ -562,9 +608,11 @@ static void r5l_log_endio(struct bio *bio)
bio_endio(bi);
atomic_dec(&io->pending_stripe);
}
- if (atomic_read(&io->pending_stripe) == 0)
- __r5l_stripe_write_finished(io);
}
+
+ /* finish flush only io_unit and PAYLOAD_FLUSH only io_unit */
+ if (atomic_read(&io->pending_stripe) == 0)
+ __r5l_stripe_write_finished(io);
}
static void r5l_do_submit_io(struct r5l_log *log, struct r5l_io_unit *io)
@@ -575,20 +623,30 @@ static void r5l_do_submit_io(struct r5l_log *log, struct r5l_io_unit *io)
__r5l_set_io_unit_state(io, IO_UNIT_IO_START);
spin_unlock_irqrestore(&log->io_list_lock, flags);
+ /*
+ * In case of journal device failures, submit_bio will get error
+ * and calls endio, then active stripes will continue write
+ * process. Therefore, it is not necessary to check Faulty bit
+ * of journal device here.
+ *
+ * We can't check split_bio after current_bio is submitted. If
+ * io->split_bio is null, after current_bio is submitted, current_bio
+ * might already be completed and the io_unit is freed. We submit
+ * split_bio first to avoid the issue.
+ */
+ if (io->split_bio) {
+ if (io->has_flush)
+ io->split_bio->bi_opf |= REQ_PREFLUSH;
+ if (io->has_fua)
+ io->split_bio->bi_opf |= REQ_FUA;
+ submit_bio(io->split_bio);
+ }
+
if (io->has_flush)
io->current_bio->bi_opf |= REQ_PREFLUSH;
if (io->has_fua)
io->current_bio->bi_opf |= REQ_FUA;
submit_bio(io->current_bio);
-
- if (!io->split_bio)
- return;
-
- if (io->has_flush)
- io->split_bio->bi_opf |= REQ_PREFLUSH;
- if (io->has_fua)
- io->split_bio->bi_opf |= REQ_FUA;
- submit_bio(io->split_bio);
}
/* deferred io_unit will be dispatched here */
@@ -623,6 +681,11 @@ static void r5c_disable_writeback_async(struct work_struct *work)
return;
pr_info("md/raid:%s: Disabling writeback cache for degraded array.\n",
mdname(mddev));
+
+ /* wait superblock change before suspend */
+ wait_event(mddev->sb_wait,
+ !test_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags));
+
mddev_suspend(mddev);
log->r5c_journal_mode = R5C_JOURNAL_MODE_WRITE_THROUGH;
mddev_resume(mddev);
@@ -786,6 +849,41 @@ static void r5l_append_payload_page(struct r5l_log *log, struct page *page)
r5_reserve_log_entry(log, io);
}
+static void r5l_append_flush_payload(struct r5l_log *log, sector_t sect)
+{
+ struct mddev *mddev = log->rdev->mddev;
+ struct r5conf *conf = mddev->private;
+ struct r5l_io_unit *io;
+ struct r5l_payload_flush *payload;
+ int meta_size;
+
+ /*
+ * payload_flush requires extra writes to the journal.
+ * To avoid handling the extra IO in quiesce, just skip
+ * flush_payload
+ */
+ if (conf->quiesce)
+ return;
+
+ mutex_lock(&log->io_mutex);
+ meta_size = sizeof(struct r5l_payload_flush) + sizeof(__le64);
+
+ if (r5l_get_meta(log, meta_size)) {
+ mutex_unlock(&log->io_mutex);
+ return;
+ }
+
+ /* current implementation is one stripe per flush payload */
+ io = log->current_io;
+ payload = page_address(io->meta_page) + io->meta_offset;
+ payload->header.type = cpu_to_le16(R5LOG_PAYLOAD_FLUSH);
+ payload->header.flags = cpu_to_le16(0);
+ payload->size = cpu_to_le32(sizeof(__le64));
+ payload->flush_stripes[0] = cpu_to_le64(sect);
+ io->meta_offset += meta_size;
+ mutex_unlock(&log->io_mutex);
+}
+
static int r5l_log_stripe(struct r5l_log *log, struct stripe_head *sh,
int data_pages, int parity_pages)
{
@@ -1149,7 +1247,7 @@ static void r5l_log_flush_endio(struct bio *bio)
unsigned long flags;
struct r5l_io_unit *io;
- if (bio->bi_error)
+ if (bio->bi_status)
md_error(log->rdev->mddev, log->rdev);
spin_lock_irqsave(&log->io_list_lock, flags);
@@ -1271,6 +1369,10 @@ static void r5c_flush_stripe(struct r5conf *conf, struct stripe_head *sh)
atomic_inc(&conf->active_stripes);
r5c_make_stripe_write_out(sh);
+ if (test_bit(STRIPE_R5C_PARTIAL_STRIPE, &sh->state))
+ atomic_inc(&conf->r5c_flushing_partial_stripes);
+ else
+ atomic_inc(&conf->r5c_flushing_full_stripes);
raid5_release_stripe(sh);
}
@@ -1313,12 +1415,16 @@ static void r5c_do_reclaim(struct r5conf *conf)
unsigned long flags;
int total_cached;
int stripes_to_flush;
+ int flushing_partial, flushing_full;
if (!r5c_is_writeback(log))
return;
+ flushing_partial = atomic_read(&conf->r5c_flushing_partial_stripes);
+ flushing_full = atomic_read(&conf->r5c_flushing_full_stripes);
total_cached = atomic_read(&conf->r5c_cached_partial_stripes) +
- atomic_read(&conf->r5c_cached_full_stripes);
+ atomic_read(&conf->r5c_cached_full_stripes) -
+ flushing_full - flushing_partial;
if (total_cached > conf->min_nr_stripes * 3 / 4 ||
atomic_read(&conf->empty_inactive_list_nr) > 0)
@@ -1328,8 +1434,8 @@ static void r5c_do_reclaim(struct r5conf *conf)
*/
stripes_to_flush = R5C_RECLAIM_STRIPE_GROUP;
else if (total_cached > conf->min_nr_stripes * 1 / 2 ||
- atomic_read(&conf->r5c_cached_full_stripes) >
- R5C_FULL_STRIPE_FLUSH_BATCH)
+ atomic_read(&conf->r5c_cached_full_stripes) - flushing_full >
+ R5C_FULL_STRIPE_FLUSH_BATCH(conf))
/*
* if stripe cache pressure moderate, or if there is many full
* stripes,flush all full stripes
@@ -1362,9 +1468,9 @@ static void r5c_do_reclaim(struct r5conf *conf)
!test_bit(STRIPE_HANDLE, &sh->state) &&
atomic_read(&sh->count) == 0) {
r5c_flush_stripe(conf, sh);
+ if (count++ >= R5C_RECLAIM_STRIPE_GROUP)
+ break;
}
- if (count++ >= R5C_RECLAIM_STRIPE_GROUP)
- break;
}
spin_unlock(&conf->device_lock);
spin_unlock_irqrestore(&log->stripe_in_journal_lock, flags);
@@ -1488,6 +1594,8 @@ bool r5l_log_disk_error(struct r5conf *conf)
return ret;
}
+#define R5L_RECOVERY_PAGE_POOL_SIZE 256
+
struct r5l_recovery_ctx {
struct page *meta_page; /* current meta */
sector_t meta_total_blocks; /* total size of current meta and data */
@@ -1496,18 +1604,131 @@ struct r5l_recovery_ctx {
int data_parity_stripes; /* number of data_parity stripes */
int data_only_stripes; /* number of data_only stripes */
struct list_head cached_list;
+
+ /*
+ * read ahead page pool (ra_pool)
+ * in recovery, log is read sequentially. It is not efficient to
+ * read every page with sync_page_io(). The read ahead page pool
+ * reads multiple pages with one IO, so further log read can
+ * just copy data from the pool.
+ */
+ struct page *ra_pool[R5L_RECOVERY_PAGE_POOL_SIZE];
+ sector_t pool_offset; /* offset of first page in the pool */
+ int total_pages; /* total allocated pages */
+ int valid_pages; /* pages with valid data */
+ struct bio *ra_bio; /* bio to do the read ahead */
};
+static int r5l_recovery_allocate_ra_pool(struct r5l_log *log,
+ struct r5l_recovery_ctx *ctx)
+{
+ struct page *page;
+
+ ctx->ra_bio = bio_alloc_bioset(GFP_KERNEL, BIO_MAX_PAGES, log->bs);
+ if (!ctx->ra_bio)
+ return -ENOMEM;
+
+ ctx->valid_pages = 0;
+ ctx->total_pages = 0;
+ while (ctx->total_pages < R5L_RECOVERY_PAGE_POOL_SIZE) {
+ page = alloc_page(GFP_KERNEL);
+
+ if (!page)
+ break;
+ ctx->ra_pool[ctx->total_pages] = page;
+ ctx->total_pages += 1;
+ }
+
+ if (ctx->total_pages == 0) {
+ bio_put(ctx->ra_bio);
+ return -ENOMEM;
+ }
+
+ ctx->pool_offset = 0;
+ return 0;
+}
+
+static void r5l_recovery_free_ra_pool(struct r5l_log *log,
+ struct r5l_recovery_ctx *ctx)
+{
+ int i;
+
+ for (i = 0; i < ctx->total_pages; ++i)
+ put_page(ctx->ra_pool[i]);
+ bio_put(ctx->ra_bio);
+}
+
+/*
+ * fetch ctx->valid_pages pages from offset
+ * In normal cases, ctx->valid_pages == ctx->total_pages after the call.
+ * However, if the offset is close to the end of the journal device,
+ * ctx->valid_pages could be smaller than ctx->total_pages
+ */
+static int r5l_recovery_fetch_ra_pool(struct r5l_log *log,
+ struct r5l_recovery_ctx *ctx,
+ sector_t offset)
+{
+ bio_reset(ctx->ra_bio);
+ ctx->ra_bio->bi_bdev = log->rdev->bdev;
+ bio_set_op_attrs(ctx->ra_bio, REQ_OP_READ, 0);
+ ctx->ra_bio->bi_iter.bi_sector = log->rdev->data_offset + offset;
+
+ ctx->valid_pages = 0;
+ ctx->pool_offset = offset;
+
+ while (ctx->valid_pages < ctx->total_pages) {
+ bio_add_page(ctx->ra_bio,
+ ctx->ra_pool[ctx->valid_pages], PAGE_SIZE, 0);
+ ctx->valid_pages += 1;
+
+ offset = r5l_ring_add(log, offset, BLOCK_SECTORS);
+
+ if (offset == 0) /* reached end of the device */
+ break;
+ }
+
+ return submit_bio_wait(ctx->ra_bio);
+}
+
+/*
+ * try read a page from the read ahead page pool, if the page is not in the
+ * pool, call r5l_recovery_fetch_ra_pool
+ */
+static int r5l_recovery_read_page(struct r5l_log *log,
+ struct r5l_recovery_ctx *ctx,
+ struct page *page,
+ sector_t offset)
+{
+ int ret;
+
+ if (offset < ctx->pool_offset ||
+ offset >= ctx->pool_offset + ctx->valid_pages * BLOCK_SECTORS) {
+ ret = r5l_recovery_fetch_ra_pool(log, ctx, offset);
+ if (ret)
+ return ret;
+ }
+
+ BUG_ON(offset < ctx->pool_offset ||
+ offset >= ctx->pool_offset + ctx->valid_pages * BLOCK_SECTORS);
+
+ memcpy(page_address(page),
+ page_address(ctx->ra_pool[(offset - ctx->pool_offset) >>
+ BLOCK_SECTOR_SHIFT]),
+ PAGE_SIZE);
+ return 0;
+}
+
static int r5l_recovery_read_meta_block(struct r5l_log *log,
struct r5l_recovery_ctx *ctx)
{
struct page *page = ctx->meta_page;
struct r5l_meta_block *mb;
u32 crc, stored_crc;
+ int ret;
- if (!sync_page_io(log->rdev, ctx->pos, PAGE_SIZE, page, REQ_OP_READ, 0,
- false))
- return -EIO;
+ ret = r5l_recovery_read_page(log, ctx, page, ctx->pos);
+ if (ret != 0)
+ return ret;
mb = page_address(page);
stored_crc = le32_to_cpu(mb->checksum);
@@ -1561,7 +1782,7 @@ static int r5l_log_write_empty_meta_block(struct r5l_log *log, sector_t pos,
mb->checksum = cpu_to_le32(crc32c_le(log->uuid_checksum,
mb, PAGE_SIZE));
if (!sync_page_io(log->rdev, pos, PAGE_SIZE, page, REQ_OP_WRITE,
- REQ_FUA, false)) {
+ REQ_SYNC | REQ_FUA, false)) {
__free_page(page);
return -EIO;
}
@@ -1589,8 +1810,7 @@ static void r5l_recovery_load_data(struct r5l_log *log,
raid5_compute_sector(conf,
le64_to_cpu(payload->location), 0,
&dd_idx, sh);
- sync_page_io(log->rdev, log_offset, PAGE_SIZE,
- sh->dev[dd_idx].page, REQ_OP_READ, 0, false);
+ r5l_recovery_read_page(log, ctx, sh->dev[dd_idx].page, log_offset);
sh->dev[dd_idx].log_checksum =
le32_to_cpu(payload->checksum[0]);
ctx->meta_total_blocks += BLOCK_SECTORS;
@@ -1609,17 +1829,15 @@ static void r5l_recovery_load_parity(struct r5l_log *log,
struct r5conf *conf = mddev->private;
ctx->meta_total_blocks += BLOCK_SECTORS * conf->max_degraded;
- sync_page_io(log->rdev, log_offset, PAGE_SIZE,
- sh->dev[sh->pd_idx].page, REQ_OP_READ, 0, false);
+ r5l_recovery_read_page(log, ctx, sh->dev[sh->pd_idx].page, log_offset);
sh->dev[sh->pd_idx].log_checksum =
le32_to_cpu(payload->checksum[0]);
set_bit(R5_Wantwrite, &sh->dev[sh->pd_idx].flags);
if (sh->qd_idx >= 0) {
- sync_page_io(log->rdev,
- r5l_ring_add(log, log_offset, BLOCK_SECTORS),
- PAGE_SIZE, sh->dev[sh->qd_idx].page,
- REQ_OP_READ, 0, false);
+ r5l_recovery_read_page(
+ log, ctx, sh->dev[sh->qd_idx].page,
+ r5l_ring_add(log, log_offset, BLOCK_SECTORS));
sh->dev[sh->qd_idx].log_checksum =
le32_to_cpu(payload->checksum[1]);
set_bit(R5_Wantwrite, &sh->dev[sh->qd_idx].flags);
@@ -1750,14 +1968,15 @@ r5c_recovery_replay_stripes(struct list_head *cached_stripe_list,
/* if matches return 0; otherwise return -EINVAL */
static int
-r5l_recovery_verify_data_checksum(struct r5l_log *log, struct page *page,
+r5l_recovery_verify_data_checksum(struct r5l_log *log,
+ struct r5l_recovery_ctx *ctx,
+ struct page *page,
sector_t log_offset, __le32 log_checksum)
{
void *addr;
u32 checksum;
- sync_page_io(log->rdev, log_offset, PAGE_SIZE,
- page, REQ_OP_READ, 0, false);
+ r5l_recovery_read_page(log, ctx, page, log_offset);
addr = kmap_atomic(page);
checksum = crc32c_le(log->uuid_checksum, addr, PAGE_SIZE);
kunmap_atomic(addr);
@@ -1779,6 +1998,7 @@ r5l_recovery_verify_data_checksum_for_mb(struct r5l_log *log,
sector_t log_offset = r5l_ring_add(log, ctx->pos, BLOCK_SECTORS);
struct page *page;
struct r5l_payload_data_parity *payload;
+ struct r5l_payload_flush *payload_flush;
page = alloc_page(GFP_KERNEL);
if (!page)
@@ -1786,33 +2006,42 @@ r5l_recovery_verify_data_checksum_for_mb(struct r5l_log *log,
while (mb_offset < le32_to_cpu(mb->meta_size)) {
payload = (void *)mb + mb_offset;
+ payload_flush = (void *)mb + mb_offset;
- if (payload->header.type == R5LOG_PAYLOAD_DATA) {
+ if (le16_to_cpu(payload->header.type) == R5LOG_PAYLOAD_DATA) {
if (r5l_recovery_verify_data_checksum(
- log, page, log_offset,
+ log, ctx, page, log_offset,
payload->checksum[0]) < 0)
goto mismatch;
- } else if (payload->header.type == R5LOG_PAYLOAD_PARITY) {
+ } else if (le16_to_cpu(payload->header.type) == R5LOG_PAYLOAD_PARITY) {
if (r5l_recovery_verify_data_checksum(
- log, page, log_offset,
+ log, ctx, page, log_offset,
payload->checksum[0]) < 0)
goto mismatch;
if (conf->max_degraded == 2 && /* q for RAID 6 */
r5l_recovery_verify_data_checksum(
- log, page,
+ log, ctx, page,
r5l_ring_add(log, log_offset,
BLOCK_SECTORS),
payload->checksum[1]) < 0)
goto mismatch;
- } else /* not R5LOG_PAYLOAD_DATA or R5LOG_PAYLOAD_PARITY */
+ } else if (le16_to_cpu(payload->header.type) == R5LOG_PAYLOAD_FLUSH) {
+ /* nothing to do for R5LOG_PAYLOAD_FLUSH here */
+ } else /* not R5LOG_PAYLOAD_DATA/PARITY/FLUSH */
goto mismatch;
- log_offset = r5l_ring_add(log, log_offset,
- le32_to_cpu(payload->size));
+ if (le16_to_cpu(payload->header.type) == R5LOG_PAYLOAD_FLUSH) {
+ mb_offset += sizeof(struct r5l_payload_flush) +
+ le32_to_cpu(payload_flush->size);
+ } else {
+ /* DATA or PARITY payload */
+ log_offset = r5l_ring_add(log, log_offset,
+ le32_to_cpu(payload->size));
+ mb_offset += sizeof(struct r5l_payload_data_parity) +
+ sizeof(__le32) *
+ (le32_to_cpu(payload->size) >> (PAGE_SHIFT - 9));
+ }
- mb_offset += sizeof(struct r5l_payload_data_parity) +
- sizeof(__le32) *
- (le32_to_cpu(payload->size) >> (PAGE_SHIFT - 9));
}
put_page(page);
@@ -1840,6 +2069,7 @@ r5c_recovery_analyze_meta_block(struct r5l_log *log,
struct r5conf *conf = mddev->private;
struct r5l_meta_block *mb;
struct r5l_payload_data_parity *payload;
+ struct r5l_payload_flush *payload_flush;
int mb_offset;
sector_t log_offset;
sector_t stripe_sect;
@@ -1865,7 +2095,31 @@ r5c_recovery_analyze_meta_block(struct r5l_log *log,
int dd;
payload = (void *)mb + mb_offset;
- stripe_sect = (payload->header.type == R5LOG_PAYLOAD_DATA) ?
+ payload_flush = (void *)mb + mb_offset;
+
+ if (le16_to_cpu(payload->header.type) == R5LOG_PAYLOAD_FLUSH) {
+ int i, count;
+
+ count = le32_to_cpu(payload_flush->size) / sizeof(__le64);
+ for (i = 0; i < count; ++i) {
+ stripe_sect = le64_to_cpu(payload_flush->flush_stripes[i]);
+ sh = r5c_recovery_lookup_stripe(cached_stripe_list,
+ stripe_sect);
+ if (sh) {
+ WARN_ON(test_bit(STRIPE_R5C_CACHING, &sh->state));
+ r5l_recovery_reset_stripe(sh);
+ list_del_init(&sh->lru);
+ raid5_release_stripe(sh);
+ }
+ }
+
+ mb_offset += sizeof(struct r5l_payload_flush) +
+ le32_to_cpu(payload_flush->size);
+ continue;
+ }
+
+ /* DATA or PARITY payload */
+ stripe_sect = (le16_to_cpu(payload->header.type) == R5LOG_PAYLOAD_DATA) ?
raid5_compute_sector(
conf, le64_to_cpu(payload->location), 0, &dd,
NULL)
@@ -1903,7 +2157,7 @@ r5c_recovery_analyze_meta_block(struct r5l_log *log,
list_add_tail(&sh->lru, cached_stripe_list);
}
- if (payload->header.type == R5LOG_PAYLOAD_DATA) {
+ if (le16_to_cpu(payload->header.type) == R5LOG_PAYLOAD_DATA) {
if (!test_bit(STRIPE_R5C_CACHING, &sh->state) &&
test_bit(R5_Wantwrite, &sh->dev[sh->pd_idx].flags)) {
r5l_recovery_replay_one_stripe(conf, sh, ctx);
@@ -1911,7 +2165,7 @@ r5c_recovery_analyze_meta_block(struct r5l_log *log,
}
r5l_recovery_load_data(log, sh, ctx, payload,
log_offset);
- } else if (payload->header.type == R5LOG_PAYLOAD_PARITY)
+ } else if (le16_to_cpu(payload->header.type) == R5LOG_PAYLOAD_PARITY)
r5l_recovery_load_parity(log, sh, ctx, payload,
log_offset);
else
@@ -2113,7 +2367,7 @@ r5c_recovery_rewrite_data_only_stripes(struct r5l_log *log,
payload = (void *)mb + offset;
payload->header.type = cpu_to_le16(
R5LOG_PAYLOAD_DATA);
- payload->size = BLOCK_SECTORS;
+ payload->size = cpu_to_le32(BLOCK_SECTORS);
payload->location = cpu_to_le64(
raid5_compute_blocknr(sh, i, 0));
addr = kmap_atomic(dev->page);
@@ -2134,7 +2388,7 @@ r5c_recovery_rewrite_data_only_stripes(struct r5l_log *log,
mb->checksum = cpu_to_le32(crc32c_le(log->uuid_checksum,
mb, PAGE_SIZE));
sync_page_io(log->rdev, ctx->pos, PAGE_SIZE, page,
- REQ_OP_WRITE, REQ_FUA, false);
+ REQ_OP_WRITE, REQ_SYNC | REQ_FUA, false);
sh->log_start = ctx->pos;
list_add_tail(&sh->r5c, &log->stripe_in_journal_list);
atomic_inc(&log->stripe_in_journal_count);
@@ -2177,55 +2431,70 @@ static void r5c_recovery_flush_data_only_stripes(struct r5l_log *log,
static int r5l_recovery_log(struct r5l_log *log)
{
struct mddev *mddev = log->rdev->mddev;
- struct r5l_recovery_ctx ctx;
+ struct r5l_recovery_ctx *ctx;
int ret;
sector_t pos;
- ctx.pos = log->last_checkpoint;
- ctx.seq = log->last_cp_seq;
- ctx.meta_page = alloc_page(GFP_KERNEL);
- ctx.data_only_stripes = 0;
- ctx.data_parity_stripes = 0;
- INIT_LIST_HEAD(&ctx.cached_list);
-
- if (!ctx.meta_page)
+ ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
+ if (!ctx)
return -ENOMEM;
- ret = r5c_recovery_flush_log(log, &ctx);
- __free_page(ctx.meta_page);
+ ctx->pos = log->last_checkpoint;
+ ctx->seq = log->last_cp_seq;
+ INIT_LIST_HEAD(&ctx->cached_list);
+ ctx->meta_page = alloc_page(GFP_KERNEL);
- if (ret)
- return ret;
+ if (!ctx->meta_page) {
+ ret = -ENOMEM;
+ goto meta_page;
+ }
+
+ if (r5l_recovery_allocate_ra_pool(log, ctx) != 0) {
+ ret = -ENOMEM;
+ goto ra_pool;
+ }
- pos = ctx.pos;
- ctx.seq += 10000;
+ ret = r5c_recovery_flush_log(log, ctx);
+ if (ret)
+ goto error;
- if ((ctx.data_only_stripes == 0) && (ctx.data_parity_stripes == 0))
+ pos = ctx->pos;
+ ctx->seq += 10000;
+
+ if ((ctx->data_only_stripes == 0) && (ctx->data_parity_stripes == 0))
pr_debug("md/raid:%s: starting from clean shutdown\n",
mdname(mddev));
else
pr_debug("md/raid:%s: recovering %d data-only stripes and %d data-parity stripes\n",
- mdname(mddev), ctx.data_only_stripes,
- ctx.data_parity_stripes);
-
- if (ctx.data_only_stripes == 0) {
- log->next_checkpoint = ctx.pos;
- r5l_log_write_empty_meta_block(log, ctx.pos, ctx.seq++);
- ctx.pos = r5l_ring_add(log, ctx.pos, BLOCK_SECTORS);
- } else if (r5c_recovery_rewrite_data_only_stripes(log, &ctx)) {
+ mdname(mddev), ctx->data_only_stripes,
+ ctx->data_parity_stripes);
+
+ if (ctx->data_only_stripes == 0) {
+ log->next_checkpoint = ctx->pos;
+ r5l_log_write_empty_meta_block(log, ctx->pos, ctx->seq++);
+ ctx->pos = r5l_ring_add(log, ctx->pos, BLOCK_SECTORS);
+ } else if (r5c_recovery_rewrite_data_only_stripes(log, ctx)) {
pr_err("md/raid:%s: failed to rewrite stripes to journal\n",
mdname(mddev));
- return -EIO;
+ ret = -EIO;
+ goto error;
}
- log->log_start = ctx.pos;
- log->seq = ctx.seq;
+ log->log_start = ctx->pos;
+ log->seq = ctx->seq;
log->last_checkpoint = pos;
r5l_write_super(log, pos);
- r5c_recovery_flush_data_only_stripes(log, &ctx);
- return 0;
+ r5c_recovery_flush_data_only_stripes(log, ctx);
+ ret = 0;
+error:
+ r5l_recovery_free_ra_pool(log, ctx);
+ra_pool:
+ __free_page(ctx->meta_page);
+meta_page:
+ kfree(ctx);
+ return ret;
}
static void r5l_write_super(struct r5l_log *log, sector_t cp)
@@ -2263,40 +2532,56 @@ static ssize_t r5c_journal_mode_show(struct mddev *mddev, char *page)
return ret;
}
-static ssize_t r5c_journal_mode_store(struct mddev *mddev,
- const char *page, size_t length)
+/*
+ * Set journal cache mode on @mddev (external API initially needed by dm-raid).
+ *
+ * @mode as defined in 'enum r5c_journal_mode'.
+ *
+ */
+int r5c_journal_mode_set(struct mddev *mddev, int mode)
{
struct r5conf *conf = mddev->private;
struct r5l_log *log = conf->log;
- int val = -1, i;
- int len = length;
if (!log)
return -ENODEV;
- if (len && page[len - 1] == '\n')
- len -= 1;
- for (i = 0; i < ARRAY_SIZE(r5c_journal_mode_str); i++)
- if (strlen(r5c_journal_mode_str[i]) == len &&
- strncmp(page, r5c_journal_mode_str[i], len) == 0) {
- val = i;
- break;
- }
- if (val < R5C_JOURNAL_MODE_WRITE_THROUGH ||
- val > R5C_JOURNAL_MODE_WRITE_BACK)
+ if (mode < R5C_JOURNAL_MODE_WRITE_THROUGH ||
+ mode > R5C_JOURNAL_MODE_WRITE_BACK)
return -EINVAL;
if (raid5_calc_degraded(conf) > 0 &&
- val == R5C_JOURNAL_MODE_WRITE_BACK)
+ mode == R5C_JOURNAL_MODE_WRITE_BACK)
return -EINVAL;
mddev_suspend(mddev);
- conf->log->r5c_journal_mode = val;
+ conf->log->r5c_journal_mode = mode;
mddev_resume(mddev);
pr_debug("md/raid:%s: setting r5c cache mode to %d: %s\n",
- mdname(mddev), val, r5c_journal_mode_str[val]);
- return length;
+ mdname(mddev), mode, r5c_journal_mode_str[mode]);
+ return 0;
+}
+EXPORT_SYMBOL(r5c_journal_mode_set);
+
+static ssize_t r5c_journal_mode_store(struct mddev *mddev,
+ const char *page, size_t length)
+{
+ int mode = ARRAY_SIZE(r5c_journal_mode_str);
+ size_t len = length;
+
+ if (len < 2)
+ return -EINVAL;
+
+ if (page[len - 1] == '\n')
+ len--;
+
+ while (mode--)
+ if (strlen(r5c_journal_mode_str[mode]) == len &&
+ !strncmp(page, r5c_journal_mode_str[mode], len))
+ break;
+
+ return r5c_journal_mode_set(mddev, mode) ?: length;
}
struct md_sysfs_entry
@@ -2320,6 +2605,10 @@ int r5c_try_caching_write(struct r5conf *conf,
int i;
struct r5dev *dev;
int to_cache = 0;
+ void **pslot;
+ sector_t tree_index;
+ int ret;
+ uintptr_t refcount;
BUG_ON(!r5c_is_writeback(log));
@@ -2348,8 +2637,11 @@ int r5c_try_caching_write(struct r5conf *conf,
* When run in degraded mode, array is set to write-through mode.
* This check helps drain pending write safely in the transition to
* write-through mode.
+ *
+ * When a stripe is syncing, the write is also handled in write
+ * through mode.
*/
- if (s->failed) {
+ if (s->failed || test_bit(STRIPE_SYNCING, &sh->state)) {
r5c_make_stripe_write_out(sh);
return -EAGAIN;
}
@@ -2364,6 +2656,44 @@ int r5c_try_caching_write(struct r5conf *conf,
}
}
+ /* if the stripe is not counted in big_stripe_tree, add it now */
+ if (!test_bit(STRIPE_R5C_PARTIAL_STRIPE, &sh->state) &&
+ !test_bit(STRIPE_R5C_FULL_STRIPE, &sh->state)) {
+ tree_index = r5c_tree_index(conf, sh->sector);
+ spin_lock(&log->tree_lock);
+ pslot = radix_tree_lookup_slot(&log->big_stripe_tree,
+ tree_index);
+ if (pslot) {
+ refcount = (uintptr_t)radix_tree_deref_slot_protected(
+ pslot, &log->tree_lock) >>
+ R5C_RADIX_COUNT_SHIFT;
+ radix_tree_replace_slot(
+ &log->big_stripe_tree, pslot,
+ (void *)((refcount + 1) << R5C_RADIX_COUNT_SHIFT));
+ } else {
+ /*
+ * this radix_tree_insert can fail safely, so no
+ * need to call radix_tree_preload()
+ */
+ ret = radix_tree_insert(
+ &log->big_stripe_tree, tree_index,
+ (void *)(1 << R5C_RADIX_COUNT_SHIFT));
+ if (ret) {
+ spin_unlock(&log->tree_lock);
+ r5c_make_stripe_write_out(sh);
+ return -EAGAIN;
+ }
+ }
+ spin_unlock(&log->tree_lock);
+
+ /*
+ * set STRIPE_R5C_PARTIAL_STRIPE, this shows the stripe is
+ * counted in the radix tree
+ */
+ set_bit(STRIPE_R5C_PARTIAL_STRIPE, &sh->state);
+ atomic_inc(&conf->r5c_cached_partial_stripes);
+ }
+
for (i = disks; i--; ) {
dev = &sh->dev[i];
if (dev->towrite) {
@@ -2438,17 +2768,20 @@ void r5c_finish_stripe_write_out(struct r5conf *conf,
struct stripe_head *sh,
struct stripe_head_state *s)
{
+ struct r5l_log *log = conf->log;
int i;
int do_wakeup = 0;
+ sector_t tree_index;
+ void **pslot;
+ uintptr_t refcount;
- if (!conf->log ||
- !test_bit(R5_InJournal, &sh->dev[sh->pd_idx].flags))
+ if (!log || !test_bit(R5_InJournal, &sh->dev[sh->pd_idx].flags))
return;
WARN_ON(test_bit(STRIPE_R5C_CACHING, &sh->state));
clear_bit(R5_InJournal, &sh->dev[sh->pd_idx].flags);
- if (conf->log->r5c_journal_mode == R5C_JOURNAL_MODE_WRITE_THROUGH)
+ if (log->r5c_journal_mode == R5C_JOURNAL_MODE_WRITE_THROUGH)
return;
for (i = sh->disks; i--; ) {
@@ -2470,17 +2803,53 @@ void r5c_finish_stripe_write_out(struct r5conf *conf,
if (do_wakeup)
wake_up(&conf->wait_for_overlap);
- spin_lock_irq(&conf->log->stripe_in_journal_lock);
+ spin_lock_irq(&log->stripe_in_journal_lock);
list_del_init(&sh->r5c);
- spin_unlock_irq(&conf->log->stripe_in_journal_lock);
+ spin_unlock_irq(&log->stripe_in_journal_lock);
sh->log_start = MaxSector;
- atomic_dec(&conf->log->stripe_in_journal_count);
- r5c_update_log_state(conf->log);
+
+ atomic_dec(&log->stripe_in_journal_count);
+ r5c_update_log_state(log);
+
+ /* stop counting this stripe in big_stripe_tree */
+ if (test_bit(STRIPE_R5C_PARTIAL_STRIPE, &sh->state) ||
+ test_bit(STRIPE_R5C_FULL_STRIPE, &sh->state)) {
+ tree_index = r5c_tree_index(conf, sh->sector);
+ spin_lock(&log->tree_lock);
+ pslot = radix_tree_lookup_slot(&log->big_stripe_tree,
+ tree_index);
+ BUG_ON(pslot == NULL);
+ refcount = (uintptr_t)radix_tree_deref_slot_protected(
+ pslot, &log->tree_lock) >>
+ R5C_RADIX_COUNT_SHIFT;
+ if (refcount == 1)
+ radix_tree_delete(&log->big_stripe_tree, tree_index);
+ else
+ radix_tree_replace_slot(
+ &log->big_stripe_tree, pslot,
+ (void *)((refcount - 1) << R5C_RADIX_COUNT_SHIFT));
+ spin_unlock(&log->tree_lock);
+ }
+
+ if (test_and_clear_bit(STRIPE_R5C_PARTIAL_STRIPE, &sh->state)) {
+ BUG_ON(atomic_read(&conf->r5c_cached_partial_stripes) == 0);
+ atomic_dec(&conf->r5c_flushing_partial_stripes);
+ atomic_dec(&conf->r5c_cached_partial_stripes);
+ }
+
+ if (test_and_clear_bit(STRIPE_R5C_FULL_STRIPE, &sh->state)) {
+ BUG_ON(atomic_read(&conf->r5c_cached_full_stripes) == 0);
+ atomic_dec(&conf->r5c_flushing_full_stripes);
+ atomic_dec(&conf->r5c_cached_full_stripes);
+ }
+
+ r5l_append_flush_payload(log, sh->sector);
+ /* stripe is flused to raid disks, we can do resync now */
+ if (test_bit(STRIPE_SYNC_REQUESTED, &sh->state))
+ set_bit(STRIPE_HANDLE, &sh->state);
}
-int
-r5c_cache_data(struct r5l_log *log, struct stripe_head *sh,
- struct stripe_head_state *s)
+int r5c_cache_data(struct r5l_log *log, struct stripe_head *sh)
{
struct r5conf *conf = sh->raid_conf;
int pages = 0;
@@ -2535,6 +2904,22 @@ r5c_cache_data(struct r5l_log *log, struct stripe_head *sh,
return 0;
}
+/* check whether this big stripe is in write back cache. */
+bool r5c_big_stripe_cached(struct r5conf *conf, sector_t sect)
+{
+ struct r5l_log *log = conf->log;
+ sector_t tree_index;
+ void *slot;
+
+ if (!log)
+ return false;
+
+ WARN_ON_ONCE(!rcu_read_lock_held());
+ tree_index = r5c_tree_index(conf, sect);
+ slot = radix_tree_lookup(&log->big_stripe_tree, tree_index);
+ return slot != NULL;
+}
+
static int r5l_load_log(struct r5l_log *log)
{
struct md_rdev *rdev = log->rdev;
@@ -2610,7 +2995,7 @@ ioerr:
return ret;
}
-void r5c_update_on_rdev_error(struct mddev *mddev)
+void r5c_update_on_rdev_error(struct mddev *mddev, struct md_rdev *rdev)
{
struct r5conf *conf = mddev->private;
struct r5l_log *log = conf->log;
@@ -2618,7 +3003,8 @@ void r5c_update_on_rdev_error(struct mddev *mddev)
if (!log)
return;
- if (raid5_calc_degraded(conf) > 0 &&
+ if ((raid5_calc_degraded(conf) > 0 ||
+ test_bit(Journal, &rdev->flags)) &&
conf->log->r5c_journal_mode == R5C_JOURNAL_MODE_WRITE_BACK)
schedule_work(&log->disable_writeback_work);
}
@@ -2627,6 +3013,10 @@ int r5l_init_log(struct r5conf *conf, struct md_rdev *rdev)
{
struct request_queue *q = bdev_get_queue(rdev->bdev);
struct r5l_log *log;
+ char b[BDEVNAME_SIZE];
+
+ pr_debug("md/raid:%s: using device %s as journal\n",
+ mdname(conf->mddev), bdevname(rdev->bdev, b));
if (PAGE_SIZE != 4096)
return -EINVAL;
@@ -2673,7 +3063,7 @@ int r5l_init_log(struct r5conf *conf, struct md_rdev *rdev)
if (!log->io_pool)
goto io_pool;
- log->bs = bioset_create(R5L_POOL_SIZE, 0);
+ log->bs = bioset_create(R5L_POOL_SIZE, 0, BIOSET_NEED_BVECS);
if (!log->bs)
goto io_bs;
@@ -2681,6 +3071,9 @@ int r5l_init_log(struct r5conf *conf, struct md_rdev *rdev)
if (!log->meta_pool)
goto out_mempool;
+ spin_lock_init(&log->tree_lock);
+ INIT_RADIX_TREE(&log->big_stripe_tree, GFP_NOWAIT | __GFP_NOWARN);
+
log->reclaim_thread = md_register_thread(r5l_reclaim_thread,
log->rdev->mddev, "reclaim");
if (!log->reclaim_thread)
@@ -2726,8 +3119,13 @@ io_kc:
return -EINVAL;
}
-void r5l_exit_log(struct r5l_log *log)
+void r5l_exit_log(struct r5conf *conf)
{
+ struct r5l_log *log = conf->log;
+
+ conf->log = NULL;
+ synchronize_rcu();
+
flush_work(&log->disable_writeback_work);
md_unregister_thread(&log->reclaim_thread);
mempool_destroy(log->meta_pool);