From a73ff3231df59a4b92ccd0dd4e73897c5822489b Mon Sep 17 00:00:00 2001 From: Lars Ellenberg Date: Mon, 25 Jun 2012 19:15:38 +0200 Subject: [PATCH] drbd: announce FLUSH/FUA capability to upper layers Unconditionally announce FLUSH/FUA to upper layers. If the lower layers on either node do not actually support this, generic_make_request() will deal with it. If this causes performance regressions on your setup, make sure there are no volatile caches involved, and mount -o nobarrier or equivalent. Signed-off-by: Philipp Reisner Signed-off-by: Lars Ellenberg --- drivers/block/drbd/drbd_actlog.c | 6 +++++- drivers/block/drbd/drbd_main.c | 1 + drivers/block/drbd/drbd_receiver.c | 21 ++++++++++++++++----- drivers/block/drbd/drbd_req.c | 3 +-- 4 files changed, 23 insertions(+), 8 deletions(-) diff --git a/drivers/block/drbd/drbd_actlog.c b/drivers/block/drbd/drbd_actlog.c index 6ace11e9e5a1..3fbef018ce55 100644 --- a/drivers/block/drbd/drbd_actlog.c +++ b/drivers/block/drbd/drbd_actlog.c @@ -876,7 +876,11 @@ int __drbd_set_out_of_sync(struct drbd_conf *mdev, sector_t sector, int size, unsigned int enr, count = 0; struct lc_element *e; - if (size <= 0 || (size & 0x1ff) != 0 || size > DRBD_MAX_BIO_SIZE) { + /* this should be an empty REQ_FLUSH */ + if (size == 0) + return 0; + + if (size < 0 || (size & 0x1ff) != 0 || size > DRBD_MAX_BIO_SIZE) { dev_err(DEV, "sector: %llus, size: %d\n", (unsigned long long)sector, size); return 0; diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c index 1ee1404769c2..2e0e7fc1dbba 100644 --- a/drivers/block/drbd/drbd_main.c +++ b/drivers/block/drbd/drbd_main.c @@ -3636,6 +3636,7 @@ struct drbd_conf *drbd_new_device(unsigned int minor) q->backing_dev_info.congested_data = mdev; blk_queue_make_request(q, drbd_make_request); + blk_queue_flush(q, REQ_FLUSH | REQ_FUA); /* Setting the max_hw_sectors to an odd value of 8kibyte here This triggers a max_bio_size message upon first attach or connect */ blk_queue_max_hw_sectors(q, DRBD_MAX_BIO_SIZE_SAFE >> 8); diff --git a/drivers/block/drbd/drbd_receiver.c b/drivers/block/drbd/drbd_receiver.c index 83d99133f94b..c74ca2df7431 100644 --- a/drivers/block/drbd/drbd_receiver.c +++ b/drivers/block/drbd/drbd_receiver.c @@ -277,6 +277,9 @@ static void drbd_pp_free(struct drbd_conf *mdev, struct page *page, int is_net) atomic_t *a = is_net ? &mdev->pp_in_use_by_net : &mdev->pp_in_use; int i; + if (page == NULL) + return; + if (drbd_pp_vacant > (DRBD_MAX_BIO_SIZE/PAGE_SIZE)*minor_count) i = page_chain_free(page); else { @@ -316,7 +319,7 @@ struct drbd_epoch_entry *drbd_alloc_ee(struct drbd_conf *mdev, gfp_t gfp_mask) __must_hold(local) { struct drbd_epoch_entry *e; - struct page *page; + struct page *page = NULL; unsigned nr_pages = (data_size + PAGE_SIZE -1) >> PAGE_SHIFT; if (drbd_insert_fault(mdev, DRBD_FAULT_AL_EE)) @@ -329,9 +332,11 @@ struct drbd_epoch_entry *drbd_alloc_ee(struct drbd_conf *mdev, return NULL; } - page = drbd_pp_alloc(mdev, nr_pages, (gfp_mask & __GFP_WAIT)); - if (!page) - goto fail; + if (data_size) { + page = drbd_pp_alloc(mdev, nr_pages, (gfp_mask & __GFP_WAIT)); + if (!page) + goto fail; + } INIT_HLIST_NODE(&e->collision); e->epoch = NULL; @@ -1270,7 +1275,6 @@ read_in_block(struct drbd_conf *mdev, u64 id, sector_t sector, int data_size) __ data_size -= dgs; - ERR_IF(data_size == 0) return NULL; ERR_IF(data_size & 0x1ff) return NULL; ERR_IF(data_size > DRBD_MAX_BIO_SIZE) return NULL; @@ -1291,6 +1295,9 @@ read_in_block(struct drbd_conf *mdev, u64 id, sector_t sector, int data_size) __ if (!e) return NULL; + if (!data_size) + return e; + ds = data_size; page = e->pages; page_chain_for_each(page) { @@ -1715,6 +1722,10 @@ static int receive_Data(struct drbd_conf *mdev, enum drbd_packets cmd, unsigned dp_flags = be32_to_cpu(p->dp_flags); rw |= wire_flags_to_bio(mdev, dp_flags); + if (e->pages == NULL) { + D_ASSERT(e->size == 0); + D_ASSERT(dp_flags & DP_FLUSH); + } if (dp_flags & DP_MAY_SET_IN_SYNC) e->flags |= EE_MAY_SET_IN_SYNC; diff --git a/drivers/block/drbd/drbd_req.c b/drivers/block/drbd/drbd_req.c index 1f4b2dbb7d4a..910335c30927 100644 --- a/drivers/block/drbd/drbd_req.c +++ b/drivers/block/drbd/drbd_req.c @@ -1111,13 +1111,12 @@ void drbd_make_request(struct request_queue *q, struct bio *bio) /* * what we "blindly" assume: */ - D_ASSERT(bio->bi_size > 0); D_ASSERT((bio->bi_size & 0x1ff) == 0); /* to make some things easier, force alignment of requests within the * granularity of our hash tables */ s_enr = bio->bi_sector >> HT_SHIFT; - e_enr = (bio->bi_sector+(bio->bi_size>>9)-1) >> HT_SHIFT; + e_enr = bio->bi_size ? (bio->bi_sector+(bio->bi_size>>9)-1) >> HT_SHIFT : s_enr; if (likely(s_enr == e_enr)) { do { -- 2.20.1