Add a struct r5l_policy and wrapper functions for non-static functions
from raid5-cache. This allows adding different policies for raid5
logging without changing the mechanism - calls from the raid5
personality stay the same.
Signed-off-by: Artur Paszkiewicz <artur.paszkiewicz@xxxxxxxxx>
---
drivers/md/raid5-cache.c | 112 +++++++++++++++++++++++++++++++++++------------
drivers/md/raid5-cache.h | 13 ++++++
2 files changed, 98 insertions(+), 27 deletions(-)
diff --git a/drivers/md/raid5-cache.c b/drivers/md/raid5-cache.c
index fc6f9fa..b10bd4c 100644
--- a/drivers/md/raid5-cache.c
+++ b/drivers/md/raid5-cache.c
@@ -727,7 +727,7 @@ static inline void r5l_add_no_space_stripe(struct r5l_log *log,
* running in raid5d, where reclaim could wait for raid5d too (when it flushes
* data from log to raid disks), so we shouldn't wait for reclaim here
*/
-int r5l_write_stripe(struct r5l_log *log, struct stripe_head *sh)
+static int __r5l_write_stripe(struct r5l_log *log, struct stripe_head *sh)
{
struct r5conf *conf = sh->raid_conf;
int write_disks = 0;
@@ -737,8 +737,6 @@ int r5l_write_stripe(struct r5l_log *log, struct stripe_head *sh)
int ret = 0;
bool wake_reclaim = false;
- if (!log)
- return -EAGAIN;
/* Don't support stripe batch */
if (sh->log_io || !test_bit(R5_Wantwrite, &sh->dev[sh->pd_idx].flags) ||
test_bit(STRIPE_SYNCING, &sh->state)) {
@@ -825,19 +823,28 @@ int r5l_write_stripe(struct r5l_log *log, struct stripe_head *sh)
return 0;
}
-void r5l_write_stripe_run(struct r5l_log *log)
+int r5l_write_stripe(struct r5l_log *log, struct stripe_head *sh)
+{
+ if (log && log->policy->write_stripe)
+ return log->policy->write_stripe(log, sh);
+ return -EAGAIN;
+}
+
+static void __r5l_write_stripe_run(struct r5l_log *log)
{
- if (!log)
- return;
mutex_lock(&log->io_mutex);
r5l_submit_current_io(log);
mutex_unlock(&log->io_mutex);
}
-int r5l_handle_flush_request(struct r5l_log *log, struct bio *bio)
+void r5l_write_stripe_run(struct r5l_log *log)
+{
+ if (log && log->policy->write_stripe_run)
+ log->policy->write_stripe_run(log);
+}
+
+static int __r5l_handle_flush_request(struct r5l_log *log, struct bio *bio)
{
- if (!log)
- return -ENODEV;
if (log->r5c_journal_mode == R5C_JOURNAL_MODE_WRITE_THROUGH) {
/*
@@ -869,6 +876,13 @@ int r5l_handle_flush_request(struct r5l_log *log, struct bio *bio)
return -EAGAIN;
}
+int r5l_handle_flush_request(struct r5l_log *log, struct bio *bio)
+{
+ if (log && log->policy->handle_flush_request)
+ return log->policy->handle_flush_request(log, bio);
+ return -ENODEV;
+}
+
/* This will run after log space is reclaimed */
static void r5l_run_no_space_stripes(struct r5l_log *log)
{
@@ -990,8 +1004,9 @@ void r5l_stripe_write_finished(struct stripe_head *sh)
io = sh->log_io;
sh->log_io = NULL;
- if (io && atomic_dec_and_test(&io->pending_stripe))
- __r5l_stripe_write_finished(io);
+ if (io && atomic_dec_and_test(&io->pending_stripe) &&
+ io->log->policy->stripe_write_finished)
+ io->log->policy->stripe_write_finished(io);
}
static void r5l_log_flush_endio(struct bio *bio)
@@ -1025,11 +1040,11 @@ static void r5l_log_flush_endio(struct bio *bio)
* only write stripes of an io_unit to raid disks till the io_unit is the first
* one whose data/parity is in log.
*/
-void r5l_flush_stripe_to_raid(struct r5l_log *log)
+static void __r5l_flush_stripe_to_raid(struct r5l_log *log)
{
bool do_flush;
- if (!log || !log->need_cache_flush)
+ if (!log->need_cache_flush)
return;
spin_lock_irq(&log->io_list_lock);
@@ -1051,6 +1066,12 @@ void r5l_flush_stripe_to_raid(struct r5l_log *log)
submit_bio(&log->flush_bio);
}
+void r5l_flush_stripe_to_raid(struct r5l_log *log)
+{
+ if (log && log->policy->flush_stripe_to_raid)
+ log->policy->flush_stripe_to_raid(log);
+}
+
static void r5l_write_super(struct r5l_log *log, sector_t cp);
static void r5l_write_super_and_discard_space(struct r5l_log *log,
sector_t end)
@@ -1307,10 +1328,10 @@ void r5l_wake_reclaim(struct r5l_log *log, sector_t space)
md_wakeup_thread(log->reclaim_thread);
}
-void r5l_quiesce(struct r5l_log *log, int state)
+static void __r5l_quiesce(struct r5l_log *log, int state)
{
struct mddev *mddev;
- if (!log || state == 2)
+ if (state == 2)
return;
if (state == 0)
kthread_unpark(log->reclaim_thread->tsk);
@@ -1324,6 +1345,12 @@ void r5l_quiesce(struct r5l_log *log, int state)
}
}
+void r5l_quiesce(struct r5l_log *log, int state)
+{
+ if (log && log->policy->quiesce)
+ log->policy->quiesce(log, state);
+}
+
bool r5l_log_disk_error(struct r5conf *conf)
{
struct r5l_log *log;
@@ -2389,11 +2416,9 @@ static int r5l_load_log(struct r5l_log *log)
return ret;
}
-int r5l_init_log(struct r5conf *conf, struct md_rdev *rdev)
+static int __r5l_init_log(struct r5l_log *log, struct r5conf *conf)
{
- struct request_queue *q = bdev_get_queue(rdev->bdev);
- struct r5l_log *log;
-
+ struct request_queue *q = bdev_get_queue(log->rdev->bdev);
if (PAGE_SIZE != 4096)
return -EINVAL;
@@ -2412,15 +2437,11 @@ int r5l_init_log(struct r5conf *conf, struct md_rdev *rdev)
return -EINVAL;
}
- log = kzalloc(sizeof(*log), GFP_KERNEL);
- if (!log)
- return -ENOMEM;
- log->rdev = rdev;
log->need_cache_flush = test_bit(QUEUE_FLAG_WC, &q->queue_flags) != 0;
- log->uuid_checksum = crc32c_le(~0, rdev->mddev->uuid,
- sizeof(rdev->mddev->uuid));
+ log->uuid_checksum = crc32c_le(~0, log->rdev->mddev->uuid,
+ sizeof(log->rdev->mddev->uuid));
mutex_init(&log->io_mutex);
@@ -2485,16 +2506,53 @@ int r5l_init_log(struct r5conf *conf, struct md_rdev *rdev)
io_pool:
kmem_cache_destroy(log->io_kc);
io_kc:
- kfree(log);
return -EINVAL;
}
-void r5l_exit_log(struct r5l_log *log)
+static void __r5l_exit_log(struct r5l_log *log)
{
md_unregister_thread(&log->reclaim_thread);
mempool_destroy(log->meta_pool);
bioset_free(log->bs);
mempool_destroy(log->io_pool);
kmem_cache_destroy(log->io_kc);
+}
+
+void r5l_exit_log(struct r5l_log *log)
+{
+ if (!log)
+ return;
+
+ if (log->policy->exit_log)
+ log->policy->exit_log(log);
+
kfree(log);
}
+
+struct r5l_policy r5l_journal = {
+ .init_log = __r5l_init_log,
+ .exit_log = __r5l_exit_log,
+ .write_stripe = __r5l_write_stripe,
+ .write_stripe_run = __r5l_write_stripe_run,
+ .flush_stripe_to_raid = __r5l_flush_stripe_to_raid,
+ .stripe_write_finished = __r5l_stripe_write_finished,
+ .handle_flush_request = __r5l_handle_flush_request,
+ .quiesce = __r5l_quiesce,
+};
+
+int r5l_init_log(struct r5conf *conf, struct md_rdev *rdev)
+{
+ int ret;
+ struct r5l_log *log = kzalloc(sizeof(*log), GFP_KERNEL);
+ if (!log)
+ return -ENOMEM;
+
+ log->rdev = rdev;
+ log->policy = &r5l_journal;
+
+ ret = log->policy->init_log(log, conf);
+ if (ret)
+ kfree(log);
+
+ return ret;
+}
diff --git a/drivers/md/raid5-cache.h b/drivers/md/raid5-cache.h
index f3d0c56..c3028a1 100644
--- a/drivers/md/raid5-cache.h
+++ b/drivers/md/raid5-cache.h
@@ -79,6 +79,8 @@ struct r5l_log {
/* to submit async io_units, to fulfill ordering of flush */
struct work_struct deferred_io_work;
+
+ struct r5l_policy *policy;
};
/*
@@ -129,6 +131,17 @@ enum r5l_io_unit_state {
IO_UNIT_STRIPE_END = 3, /* stripes data finished writing to raid */
};
+struct r5l_policy {
+ int (*init_log)(struct r5l_log *log, struct r5conf *conf);
+ void (*exit_log)(struct r5l_log *log);
+ int (*write_stripe)(struct r5l_log *log, struct stripe_head *sh);
+ void (*write_stripe_run)(struct r5l_log *log);
+ void (*flush_stripe_to_raid)(struct r5l_log *log);
+ void (*stripe_write_finished)(struct r5l_io_unit *io);
+ int (*handle_flush_request)(struct r5l_log *log, struct bio *bio);
+ void (*quiesce)(struct r5l_log *log, int state);
+};
+
extern int r5l_init_log(struct r5conf *conf, struct md_rdev *rdev);
extern void r5l_exit_log(struct r5l_log *log);
extern int r5l_write_stripe(struct r5l_log *log, struct stripe_head *sh);
--
2.10.1
--
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