From 2e9ee0955d3c2d3db56aa02ba6f948ba35d5e9c1 Mon Sep 17 00:00:00 2001 From: Pankaj Gupta Date: Fri, 5 Jul 2019 19:33:25 +0530 Subject: [PATCH] dm: enable synchronous dax This patch sets dax device 'DAXDEV_SYNC' flag if all the target devices of device mapper support synchrononous DAX. If device mapper consists of both synchronous and asynchronous dax devices, we don't set 'DAXDEV_SYNC' flag. 'dm_table_supports_dax' is refactored to pass 'iterate_devices_fn' as argument so that the callers can pass the appropriate functions. Suggested-by: Mike Snitzer Signed-off-by: Pankaj Gupta Reviewed-by: Mike Snitzer Signed-off-by: Dan Williams --- drivers/md/dm-table.c | 24 ++++++++++++++++++------ drivers/md/dm.c | 2 +- drivers/md/dm.h | 5 ++++- 3 files changed, 23 insertions(+), 8 deletions(-) diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c index 350cf0451456..81c55304c4fa 100644 --- a/drivers/md/dm-table.c +++ b/drivers/md/dm-table.c @@ -881,7 +881,7 @@ void dm_table_set_type(struct dm_table *t, enum dm_queue_mode type) EXPORT_SYMBOL_GPL(dm_table_set_type); /* validate the dax capability of the target device span */ -static int device_supports_dax(struct dm_target *ti, struct dm_dev *dev, +int device_supports_dax(struct dm_target *ti, struct dm_dev *dev, sector_t start, sector_t len, void *data) { int blocksize = *(int *) data; @@ -890,7 +890,15 @@ static int device_supports_dax(struct dm_target *ti, struct dm_dev *dev, start, len); } -bool dm_table_supports_dax(struct dm_table *t, int blocksize) +/* Check devices support synchronous DAX */ +static int device_synchronous(struct dm_target *ti, struct dm_dev *dev, + sector_t start, sector_t len, void *data) +{ + return dax_synchronous(dev->dax_dev); +} + +bool dm_table_supports_dax(struct dm_table *t, + iterate_devices_callout_fn iterate_fn, int *blocksize) { struct dm_target *ti; unsigned i; @@ -903,8 +911,7 @@ bool dm_table_supports_dax(struct dm_table *t, int blocksize) return false; if (!ti->type->iterate_devices || - !ti->type->iterate_devices(ti, device_supports_dax, - &blocksize)) + !ti->type->iterate_devices(ti, iterate_fn, blocksize)) return false; } @@ -940,6 +947,7 @@ static int dm_table_determine_type(struct dm_table *t) struct dm_target *tgt; struct list_head *devices = dm_table_get_devices(t); enum dm_queue_mode live_md_type = dm_get_md_type(t->md); + int page_size = PAGE_SIZE; if (t->type != DM_TYPE_NONE) { /* target already set the table's type */ @@ -984,7 +992,7 @@ static int dm_table_determine_type(struct dm_table *t) verify_bio_based: /* We must use this table as bio-based */ t->type = DM_TYPE_BIO_BASED; - if (dm_table_supports_dax(t, PAGE_SIZE) || + if (dm_table_supports_dax(t, device_supports_dax, &page_size) || (list_empty(devices) && live_md_type == DM_TYPE_DAX_BIO_BASED)) { t->type = DM_TYPE_DAX_BIO_BASED; } else { @@ -1883,6 +1891,7 @@ void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q, struct queue_limits *limits) { bool wc = false, fua = false; + int page_size = PAGE_SIZE; /* * Copy table's limits to the DM device's request_queue @@ -1910,8 +1919,11 @@ void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q, } blk_queue_write_cache(q, wc, fua); - if (dm_table_supports_dax(t, PAGE_SIZE)) + if (dm_table_supports_dax(t, device_supports_dax, &page_size)) { blk_queue_flag_set(QUEUE_FLAG_DAX, q); + if (dm_table_supports_dax(t, device_synchronous, NULL)) + set_dax_synchronous(t->md->dax_dev); + } else blk_queue_flag_clear(QUEUE_FLAG_DAX, q); diff --git a/drivers/md/dm.c b/drivers/md/dm.c index b1caa7188209..b92c42a72ad4 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -1119,7 +1119,7 @@ static bool dm_dax_supported(struct dax_device *dax_dev, struct block_device *bd if (!map) return false; - ret = dm_table_supports_dax(map, blocksize); + ret = dm_table_supports_dax(map, device_supports_dax, &blocksize); dm_put_live_table(md, srcu_idx); diff --git a/drivers/md/dm.h b/drivers/md/dm.h index 17e3db54404c..0475673337f3 100644 --- a/drivers/md/dm.h +++ b/drivers/md/dm.h @@ -72,7 +72,10 @@ bool dm_table_bio_based(struct dm_table *t); bool dm_table_request_based(struct dm_table *t); void dm_table_free_md_mempools(struct dm_table *t); struct dm_md_mempools *dm_table_get_md_mempools(struct dm_table *t); -bool dm_table_supports_dax(struct dm_table *t, int blocksize); +bool dm_table_supports_dax(struct dm_table *t, iterate_devices_callout_fn fn, + int *blocksize); +int device_supports_dax(struct dm_target *ti, struct dm_dev *dev, + sector_t start, sector_t len, void *data); void dm_lock_md_type(struct mapped_device *md); void dm_unlock_md_type(struct mapped_device *md); -- 2.30.2