[PATCH] drbd: Store op in drbd_peer_request

From: Christoph Böhmwalder
Date: Mon Oct 17 2022 - 05:02:42 EST

(Sort of) cherry-picked from the out-of-tree drbd9 branch. Original
commit message by Joel Colledge:

This simplifies drbd_submit_peer_request by removing most of the
arguments. It also makes the treatment of the op better aligned with
that in struct bio.

Determine fault_type dynamically using information which is already
available instead of passing it in as a parameter.

Note: The opf in receive_rs_deallocated was changed from
REQ_OP_WRITE_ZEROES to REQ_OP_DISCARD. This was required in the
out-of-tree module, and does not matter in-tree. The opf is ignored
anyway in drbd_submit_peer_request, since the discard/zero-out is
decided by the EE_TRIM flag.

Signed-off-by: Joel Colledge <joel.colledge@xxxxxxxxxx>
Signed-off-by: Christoph Böhmwalder <christoph.boehmwalder@xxxxxxxxxx>
---
drivers/block/drbd/drbd_int.h | 8 ++-
drivers/block/drbd/drbd_receiver.c | 81 +++++++++++++++++-------------
drivers/block/drbd/drbd_worker.c | 4 +-
3 files changed, 53 insertions(+), 40 deletions(-)

diff --git a/drivers/block/drbd/drbd_int.h b/drivers/block/drbd/drbd_int.h
index 4d661282ff41..0f8e3b94a635 100644
--- a/drivers/block/drbd/drbd_int.h
+++ b/drivers/block/drbd/drbd_int.h
@@ -395,6 +395,7 @@ struct drbd_peer_request {
struct drbd_peer_device *peer_device;
struct drbd_epoch *epoch; /* for writes */
struct page *pages;
+ unsigned int opf; /* to be used as bi_opf */
atomic_t pending_bios;
struct drbd_interval i;
/* see comments on ee flag bits below */
@@ -406,6 +407,10 @@ struct drbd_peer_request {
};
};

+/* Equivalent to bio_op and req_op. */
+#define peer_req_op(peer_req) \
+ ((peer_req)->opf & REQ_OP_MASK)
+
/* ee flag bits.
* While corresponding bios are in flight, the only modification will be
* set_bit WAS_ERROR, which has to be atomic.
@@ -1545,8 +1550,7 @@ extern void drbd_send_acks_wf(struct work_struct *ws);
extern bool drbd_rs_c_min_rate_throttle(struct drbd_device *device);
extern bool drbd_rs_should_slow_down(struct drbd_device *device, sector_t sector,
bool throttle_if_app_is_waiting);
-extern int drbd_submit_peer_request(struct drbd_device *,
- struct drbd_peer_request *, blk_opf_t, int);
+extern int drbd_submit_peer_request(struct drbd_peer_request *);
extern int drbd_free_peer_reqs(struct drbd_device *, struct list_head *);
extern struct drbd_peer_request *drbd_alloc_peer_req(struct drbd_peer_device *, u64,
sector_t, unsigned int,
diff --git a/drivers/block/drbd/drbd_receiver.c b/drivers/block/drbd/drbd_receiver.c
index c897c4572036..41cf706a5e7a 100644
--- a/drivers/block/drbd/drbd_receiver.c
+++ b/drivers/block/drbd/drbd_receiver.c
@@ -1603,9 +1603,19 @@ static void drbd_issue_peer_discard_or_zero_out(struct drbd_device *device, stru
drbd_endio_write_sec_final(peer_req);
}

+static int peer_request_fault_type(struct drbd_peer_request *peer_req)
+{
+ if (peer_req_op(peer_req) == REQ_OP_READ) {
+ return peer_req->flags & EE_APPLICATION ?
+ DRBD_FAULT_DT_RD : DRBD_FAULT_RS_RD;
+ } else {
+ return peer_req->flags & EE_APPLICATION ?
+ DRBD_FAULT_DT_WR : DRBD_FAULT_RS_WR;
+ }
+}
+
/**
* drbd_submit_peer_request()
- * @device: DRBD device.
* @peer_req: peer request
*
* May spread the pages to multiple bios,
@@ -1619,10 +1629,9 @@ static void drbd_issue_peer_discard_or_zero_out(struct drbd_device *device, stru
* on certain Xen deployments.
*/
/* TODO allocate from our own bio_set. */
-int drbd_submit_peer_request(struct drbd_device *device,
- struct drbd_peer_request *peer_req,
- const blk_opf_t opf, const int fault_type)
+int drbd_submit_peer_request(struct drbd_peer_request *peer_req)
{
+ struct drbd_device *device = peer_req->peer_device->device;
struct bio *bios = NULL;
struct bio *bio;
struct page *page = peer_req->pages;
@@ -1667,7 +1676,18 @@ int drbd_submit_peer_request(struct drbd_device *device,
* generated bio, but a bio allocated on behalf of the peer.
*/
next_bio:
- bio = bio_alloc(device->ldev->backing_bdev, nr_pages, opf, GFP_NOIO);
+ /* _DISCARD, _WRITE_ZEROES handled above.
+ * REQ_OP_FLUSH (empty flush) not expected,
+ * should have been mapped to a "drbd protocol barrier".
+ * REQ_OP_SECURE_ERASE: I don't see how we could ever support that.
+ */
+ if (!(peer_req_op(peer_req) == REQ_OP_WRITE ||
+ peer_req_op(peer_req) == REQ_OP_READ)) {
+ drbd_err(device, "Invalid bio op received: 0x%x\n", peer_req->opf);
+ return -EINVAL;
+ }
+
+ bio = bio_alloc(device->ldev->backing_bdev, nr_pages, peer_req->opf, GFP_NOIO);
/* > peer_req->i.sector, unless this is the first bio */
bio->bi_iter.bi_sector = sector;
bio->bi_private = peer_req;
@@ -1697,7 +1717,7 @@ int drbd_submit_peer_request(struct drbd_device *device,
bios = bios->bi_next;
bio->bi_next = NULL;

- drbd_submit_bio_noacct(device, fault_type, bio);
+ drbd_submit_bio_noacct(device, peer_request_fault_type(peer_req), bio);
} while (bios);
return 0;
}
@@ -2051,6 +2071,7 @@ static int recv_resync_read(struct drbd_peer_device *peer_device, sector_t secto
* respective _drbd_clear_done_ee */

peer_req->w.cb = e_end_resync_block;
+ peer_req->opf = REQ_OP_WRITE;
peer_req->submit_jif = jiffies;

spin_lock_irq(&device->resource->req_lock);
@@ -2058,8 +2079,7 @@ static int recv_resync_read(struct drbd_peer_device *peer_device, sector_t secto
spin_unlock_irq(&device->resource->req_lock);

atomic_add(pi->size >> 9, &device->rs_sect_ev);
- if (drbd_submit_peer_request(device, peer_req, REQ_OP_WRITE,
- DRBD_FAULT_RS_WR) == 0)
+ if (drbd_submit_peer_request(peer_req) == 0)
return 0;

/* don't care for the reason here */
@@ -2375,16 +2395,6 @@ static int wait_for_and_update_peer_seq(struct drbd_peer_device *peer_device, co
return ret;
}

-/* see also bio_flags_to_wire()
- * DRBD_REQ_*, because we need to semantically map the flags to data packet
- * flags and back. We may replicate to other kernel versions. */
-static blk_opf_t wire_flags_to_bio_flags(u32 dpf)
-{
- return (dpf & DP_RW_SYNC ? REQ_SYNC : 0) |
- (dpf & DP_FUA ? REQ_FUA : 0) |
- (dpf & DP_FLUSH ? REQ_PREFLUSH : 0);
-}
-
static enum req_op wire_flags_to_bio_op(u32 dpf)
{
if (dpf & DP_ZEROES)
@@ -2395,6 +2405,15 @@ static enum req_op wire_flags_to_bio_op(u32 dpf)
return REQ_OP_WRITE;
}

+/* see also bio_flags_to_wire() */
+static unsigned long wire_flags_to_bio(struct drbd_connection *connection, u32 dpf)
+{
+ unsigned long opf = wire_flags_to_bio_op(dpf) |
+ (dpf & DP_RW_SYNC ? REQ_SYNC : 0) |
+ (dpf & DP_FUA ? REQ_FUA : 0) |
+ (dpf & DP_FLUSH ? REQ_PREFLUSH : 0);
+}
+
static void fail_postponed_requests(struct drbd_device *device, sector_t sector,
unsigned int size)
{
@@ -2538,8 +2557,6 @@ static int receive_Data(struct drbd_connection *connection, struct packet_info *
struct drbd_peer_request *peer_req;
struct p_data *p = pi->data;
u32 peer_seq = be32_to_cpu(p->seq_num);
- enum req_op op;
- blk_opf_t op_flags;
u32 dp_flags;
int err, tp;

@@ -2578,11 +2595,10 @@ static int receive_Data(struct drbd_connection *connection, struct packet_info *
peer_req->flags |= EE_APPLICATION;

dp_flags = be32_to_cpu(p->dp_flags);
- op = wire_flags_to_bio_op(dp_flags);
- op_flags = wire_flags_to_bio_flags(dp_flags);
+ peer_req->opf = wire_flags_to_bio(connection, dp_flags);
if (pi->cmd == P_TRIM) {
D_ASSERT(peer_device, peer_req->i.size > 0);
- D_ASSERT(peer_device, op == REQ_OP_DISCARD);
+ D_ASSERT(peer_device, peer_req_op(peer_req) == REQ_OP_DISCARD);
D_ASSERT(peer_device, peer_req->pages == NULL);
/* need to play safe: an older DRBD sender
* may mean zero-out while sending P_TRIM. */
@@ -2590,7 +2606,7 @@ static int receive_Data(struct drbd_connection *connection, struct packet_info *
peer_req->flags |= EE_ZEROOUT;
} else if (pi->cmd == P_ZEROES) {
D_ASSERT(peer_device, peer_req->i.size > 0);
- D_ASSERT(peer_device, op == REQ_OP_WRITE_ZEROES);
+ D_ASSERT(peer_device, peer_req_op(peer_req) == REQ_OP_WRITE_ZEROES);
D_ASSERT(peer_device, peer_req->pages == NULL);
/* Do (not) pass down BLKDEV_ZERO_NOUNMAP? */
if (dp_flags & DP_DISCARD)
@@ -2677,8 +2693,7 @@ static int receive_Data(struct drbd_connection *connection, struct packet_info *
peer_req->flags |= EE_CALL_AL_COMPLETE_IO;
}

- err = drbd_submit_peer_request(device, peer_req, op | op_flags,
- DRBD_FAULT_DT_WR);
+ err = drbd_submit_peer_request(peer_req);
if (!err)
return 0;

@@ -2789,7 +2804,6 @@ static int receive_DataRequest(struct drbd_connection *connection, struct packet
struct drbd_peer_request *peer_req;
struct digest_info *di = NULL;
int size, verb;
- unsigned int fault_type;
struct p_block_req *p = pi->data;

peer_device = conn_peer_device(connection, pi->vnr);
@@ -2849,11 +2863,11 @@ static int receive_DataRequest(struct drbd_connection *connection, struct packet
put_ldev(device);
return -ENOMEM;
}
+ peer_req->opf = REQ_OP_READ;

switch (pi->cmd) {
case P_DATA_REQUEST:
peer_req->w.cb = w_e_end_data_req;
- fault_type = DRBD_FAULT_DT_RD;
/* application IO, don't drbd_rs_begin_io */
peer_req->flags |= EE_APPLICATION;
goto submit;
@@ -2867,14 +2881,12 @@ static int receive_DataRequest(struct drbd_connection *connection, struct packet
fallthrough;
case P_RS_DATA_REQUEST:
peer_req->w.cb = w_e_end_rsdata_req;
- fault_type = DRBD_FAULT_RS_RD;
/* used in the sector offset progress display */
device->bm_resync_fo = BM_SECT_TO_BIT(sector);
break;

case P_OV_REPLY:
case P_CSUM_RS_REQUEST:
- fault_type = DRBD_FAULT_RS_RD;
di = kmalloc(sizeof(*di) + pi->size, GFP_NOIO);
if (!di)
goto out_free_e;
@@ -2923,7 +2935,6 @@ static int receive_DataRequest(struct drbd_connection *connection, struct packet
(unsigned long long)sector);
}
peer_req->w.cb = w_e_end_ov_req;
- fault_type = DRBD_FAULT_RS_RD;
break;

default:
@@ -2975,8 +2986,7 @@ static int receive_DataRequest(struct drbd_connection *connection, struct packet
submit:
update_receiver_timing_details(connection, drbd_submit_peer_request);
inc_unacked(device);
- if (drbd_submit_peer_request(device, peer_req, REQ_OP_READ,
- fault_type) == 0)
+ if (drbd_submit_peer_request(peer_req) == 0)
return 0;

/* don't care for the reason here */
@@ -4947,7 +4957,6 @@ static int receive_rs_deallocated(struct drbd_connection *connection, struct pac

if (get_ldev(device)) {
struct drbd_peer_request *peer_req;
- const enum req_op op = REQ_OP_WRITE_ZEROES;

peer_req = drbd_alloc_peer_req(peer_device, ID_SYNCER, sector,
size, 0, GFP_NOIO);
@@ -4957,6 +4966,7 @@ static int receive_rs_deallocated(struct drbd_connection *connection, struct pac
}

peer_req->w.cb = e_end_resync_block;
+ peer_req->opf = REQ_OP_DISCARD;
peer_req->submit_jif = jiffies;
peer_req->flags |= EE_TRIM;

@@ -4965,8 +4975,7 @@ static int receive_rs_deallocated(struct drbd_connection *connection, struct pac
spin_unlock_irq(&device->resource->req_lock);

atomic_add(pi->size >> 9, &device->rs_sect_ev);
- err = drbd_submit_peer_request(device, peer_req, op,
- DRBD_FAULT_RS_WR);
+ err = drbd_submit_peer_request(peer_req);

if (err) {
spin_lock_irq(&device->resource->req_lock);
diff --git a/drivers/block/drbd/drbd_worker.c b/drivers/block/drbd/drbd_worker.c
index 0bb1a900c2d5..c69beefc9d5c 100644
--- a/drivers/block/drbd/drbd_worker.c
+++ b/drivers/block/drbd/drbd_worker.c
@@ -400,13 +400,13 @@ static int read_for_csum(struct drbd_peer_device *peer_device, sector_t sector,
goto defer;

peer_req->w.cb = w_e_send_csum;
+ peer_req->opf = REQ_OP_READ;
spin_lock_irq(&device->resource->req_lock);
list_add_tail(&peer_req->w.list, &device->read_ee);
spin_unlock_irq(&device->resource->req_lock);

atomic_add(size >> 9, &device->rs_sect_ev);
- if (drbd_submit_peer_request(device, peer_req, REQ_OP_READ,
- DRBD_FAULT_RS_RD) == 0)
+ if (drbd_submit_peer_request(peer_req) == 0)
return 0;

/* If it failed because of ENOMEM, retry should help. If it failed
--
2.37.3