From 6a35c45f890dc18c5527ac501b308058118f20e7 Mon Sep 17 00:00:00 2001 From: Philipp Reisner Date: Mon, 17 Jan 2011 20:27:30 +0100 Subject: [PATCH] drbd: Ensure that an epoch contains only requests of one kind The assert in drbd_req.c:755 forces us to have only requests of one kind in an epoch. The two kinds we distinguish here are: local-only or mirrored. Signed-off-by: Philipp Reisner Signed-off-by: Lars Ellenberg --- drivers/block/drbd/drbd_main.c | 7 ++++++- drivers/block/drbd/drbd_req.c | 29 ++++------------------------- drivers/block/drbd/drbd_req.h | 18 ++++++++++++++++++ 3 files changed, 28 insertions(+), 26 deletions(-) diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c index 1061b9fff2b0..34ee8e44a751 100644 --- a/drivers/block/drbd/drbd_main.c +++ b/drivers/block/drbd/drbd_main.c @@ -1261,9 +1261,14 @@ __drbd_set_state(struct drbd_conf *mdev, union drbd_state ns, if (os.conn < C_CONNECTED && ns.conn >= C_CONNECTED) drbd_resume_al(mdev); - if (os.conn == C_AHEAD && ns.conn != C_AHEAD) + /* Start a new epoch in case we start to mirror write requests */ + if (!drbd_should_do_remote(os) && drbd_should_do_remote(ns)) tl_forget(mdev); + /* Do not add local-only requests to an epoch with mirrored requests */ + if (drbd_should_do_remote(os) && !drbd_should_do_remote(ns)) + set_bit(CREATE_BARRIER, &mdev->flags); + ascw = kmalloc(sizeof(*ascw), GFP_ATOMIC); if (ascw) { ascw->os = os; diff --git a/drivers/block/drbd/drbd_req.c b/drivers/block/drbd/drbd_req.c index 6f9d1bfcca58..336937a14d3f 100644 --- a/drivers/block/drbd/drbd_req.c +++ b/drivers/block/drbd/drbd_req.c @@ -762,27 +762,6 @@ static int drbd_may_do_local_read(struct drbd_conf *mdev, sector_t sector, int s return 0 == drbd_bm_count_bits(mdev, sbnr, ebnr); } -static bool drbd_should_do_remote(struct drbd_conf *mdev) -{ - union drbd_state s = mdev->state; - - return s.pdsk == D_UP_TO_DATE || - (s.pdsk >= D_INCONSISTENT && - s.conn >= C_WF_BITMAP_T && - s.conn < C_AHEAD); - /* Before proto 96 that was >= CONNECTED instead of >= C_WF_BITMAP_T. - That is equivalent since before 96 IO was frozen in the C_WF_BITMAP* - states. */ -} -static bool drbd_should_send_oos(struct drbd_conf *mdev) -{ - union drbd_state s = mdev->state; - - return s.conn == C_AHEAD || s.conn == C_WF_BITMAP_S; - /* pdsk = D_INCONSISTENT as a consequence. Protocol 96 check not necessary - since we enter state C_AHEAD only if proto >= 96 */ -} - static int drbd_make_request_common(struct drbd_conf *mdev, struct bio *bio, unsigned long start_time) { const int rw = bio_rw(bio); @@ -854,8 +833,8 @@ static int drbd_make_request_common(struct drbd_conf *mdev, struct bio *bio, uns drbd_al_begin_io(mdev, sector); } - remote = remote && drbd_should_do_remote(mdev); - send_oos = rw == WRITE && drbd_should_send_oos(mdev); + remote = remote && drbd_should_do_remote(mdev->state); + send_oos = rw == WRITE && drbd_should_send_oos(mdev->state); D_ASSERT(!(remote && send_oos)); if (!(local || remote) && !is_susp(mdev->state)) { @@ -896,8 +875,8 @@ allocate_barrier: } if (remote || send_oos) { - remote = drbd_should_do_remote(mdev); - send_oos = rw == WRITE && drbd_should_send_oos(mdev); + remote = drbd_should_do_remote(mdev->state); + send_oos = rw == WRITE && drbd_should_send_oos(mdev->state); D_ASSERT(!(remote && send_oos)); if (!(remote || send_oos)) diff --git a/drivers/block/drbd/drbd_req.h b/drivers/block/drbd/drbd_req.h index 077c47b1e9d7..32c1f2a31266 100644 --- a/drivers/block/drbd/drbd_req.h +++ b/drivers/block/drbd/drbd_req.h @@ -360,4 +360,22 @@ static inline int req_mod(struct drbd_request *req, return rv; } + +static inline bool drbd_should_do_remote(union drbd_state s) +{ + return s.pdsk == D_UP_TO_DATE || + (s.pdsk >= D_INCONSISTENT && + s.conn >= C_WF_BITMAP_T && + s.conn < C_AHEAD); + /* Before proto 96 that was >= CONNECTED instead of >= C_WF_BITMAP_T. + That is equivalent since before 96 IO was frozen in the C_WF_BITMAP* + states. */ +} +static inline bool drbd_should_send_oos(union drbd_state s) +{ + return s.conn == C_AHEAD || s.conn == C_WF_BITMAP_S; + /* pdsk = D_INCONSISTENT as a consequence. Protocol 96 check not necessary + since we enter state C_AHEAD only if proto >= 96 */ +} + #endif