[PATCH 012/118] drbd: Request lookup code cleanup (4)

From: Philipp Reisner
Date: Thu Aug 25 2011 - 11:37:52 EST


From: Andreas Gruenbacher <agruen@xxxxxxxxxx>

Factor out duplicate code in got_NegAck().

Signed-off-by: Philipp Reisner <philipp.reisner@xxxxxxxxxx>
Signed-off-by: Lars Ellenberg <lars.ellenberg@xxxxxxxxxx>
---
drivers/block/drbd/drbd_receiver.c | 66 +++++++++++++++--------------------
1 files changed, 28 insertions(+), 38 deletions(-)

diff --git a/drivers/block/drbd/drbd_receiver.c b/drivers/block/drbd/drbd_receiver.c
index 84c8d94..8e7875e 100644
--- a/drivers/block/drbd/drbd_receiver.c
+++ b/drivers/block/drbd/drbd_receiver.c
@@ -1472,7 +1472,7 @@ fail:
static struct drbd_request *
find_request(struct drbd_conf *mdev,
struct hlist_head *(*hash_slot)(struct drbd_conf *, sector_t),
- u64 id, sector_t sector, const char *func)
+ u64 id, sector_t sector, bool missing_ok, const char *func)
{
struct hlist_head *slot = hash_slot(mdev, sector);
struct hlist_node *n;
@@ -1487,10 +1487,14 @@ find_request(struct drbd_conf *mdev,
func, (unsigned long)req,
(unsigned long long)req->sector,
(unsigned long long)sector);
- break;
+ return NULL;
}
return req;
}
+ if (!missing_ok) {
+ dev_err(DEV, "%s: failed to find request %lu, sector %llus\n", func,
+ (unsigned long)id, (unsigned long long)sector);
+ }
return NULL;
}

@@ -1504,12 +1508,10 @@ static int receive_DataReply(struct drbd_conf *mdev, enum drbd_packets cmd, unsi
sector = be64_to_cpu(p->sector);

spin_lock_irq(&mdev->req_lock);
- req = find_request(mdev, ar_hash_slot, p->block_id, sector, __func__);
+ req = find_request(mdev, ar_hash_slot, p->block_id, sector, false, __func__);
spin_unlock_irq(&mdev->req_lock);
- if (unlikely(!req)) {
- dev_err(DEV, "Got a corrupt block_id/sector pair(1).\n");
+ if (unlikely(!req))
return false;
- }

/* hlist_del(&req->collision) is done in _req_may_be_done, to avoid
* special casing it there for the various failure cases.
@@ -4248,18 +4250,15 @@ static int got_IsInSync(struct drbd_conf *mdev, struct p_header80 *h)
static int validate_req_change_req_state(struct drbd_conf *mdev,
u64 id, sector_t sector,
struct hlist_head *(*hash_slot)(struct drbd_conf *, sector_t),
- const char *func, enum drbd_req_event what)
+ const char *func, enum drbd_req_event what, bool missing_ok)
{
struct drbd_request *req;
struct bio_and_error m;

spin_lock_irq(&mdev->req_lock);
- req = find_request(mdev, hash_slot, id, sector, func);
+ req = find_request(mdev, hash_slot, id, sector, missing_ok, func);
if (unlikely(!req)) {
spin_unlock_irq(&mdev->req_lock);
-
- dev_err(DEV, "%s: failed to find req %p, sector %llus\n", func,
- (void *)(unsigned long)id, (unsigned long long)sector);
return false;
}
__req_mod(req, what, &m);
@@ -4307,7 +4306,8 @@ static int got_BlockAck(struct drbd_conf *mdev, struct p_header80 *h)
}

return validate_req_change_req_state(mdev, p->block_id, sector,
- tl_hash_slot, __func__, what);
+ tl_hash_slot, __func__, what,
+ false);
}

static int got_NegAck(struct drbd_conf *mdev, struct p_header80 *h)
@@ -4315,8 +4315,9 @@ static int got_NegAck(struct drbd_conf *mdev, struct p_header80 *h)
struct p_block_ack *p = (struct p_block_ack *)h;
sector_t sector = be64_to_cpu(p->sector);
int size = be32_to_cpu(p->blksize);
- struct drbd_request *req;
- struct bio_and_error m;
+ bool missing_ok = mdev->net_conf->wire_protocol == DRBD_PROT_A ||
+ mdev->net_conf->wire_protocol == DRBD_PROT_B;
+ bool found;

update_peer_seq(mdev, be32_to_cpu(p->seq_num));

@@ -4326,31 +4327,19 @@ static int got_NegAck(struct drbd_conf *mdev, struct p_header80 *h)
return true;
}

- spin_lock_irq(&mdev->req_lock);
- req = find_request(mdev, tl_hash_slot, p->block_id, sector, __func__);
- if (!req) {
- spin_unlock_irq(&mdev->req_lock);
- if (mdev->net_conf->wire_protocol == DRBD_PROT_A ||
- mdev->net_conf->wire_protocol == DRBD_PROT_B) {
- /* Protocol A has no P_WRITE_ACKs, but has P_NEG_ACKs.
- The master bio might already be completed, therefore the
- request is no longer in the collision hash.
- => Do not try to validate block_id as request. */
- /* In Protocol B we might already have got a P_RECV_ACK
- but then get a P_NEG_ACK after wards. */
- drbd_set_out_of_sync(mdev, sector, size);
- return true;
- } else {
- dev_err(DEV, "%s: failed to find req %p, sector %llus\n", __func__,
- (void *)(unsigned long)p->block_id, (unsigned long long)sector);
+ found = validate_req_change_req_state(mdev, p->block_id, sector,
+ tl_hash_slot, __func__,
+ neg_acked, missing_ok);
+ if (!found) {
+ /* Protocol A has no P_WRITE_ACKs, but has P_NEG_ACKs.
+ The master bio might already be completed, therefore the
+ request is no longer in the collision hash. */
+ /* In Protocol B we might already have got a P_RECV_ACK
+ but then get a P_NEG_ACK afterwards. */
+ if (!missing_ok)
return false;
- }
+ drbd_set_out_of_sync(mdev, sector, size);
}
- __req_mod(req, neg_acked, &m);
- spin_unlock_irq(&mdev->req_lock);
-
- if (m.bio)
- complete_master_bio(mdev, &m);
return true;
}

@@ -4364,7 +4353,8 @@ static int got_NegDReply(struct drbd_conf *mdev, struct p_header80 *h)
(unsigned long long)sector, be32_to_cpu(p->blksize));

return validate_req_change_req_state(mdev, p->block_id, sector,
- ar_hash_slot, __func__, neg_acked);
+ ar_hash_slot, __func__, neg_acked,
+ false);
}

static int got_NegRSDReply(struct drbd_conf *mdev, struct p_header80 *h)
--
1.7.4.1

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