libceph: make sure need_resend targets reflect latest map

Otherwise we may miss events like PG splits, pool deletions, etc when
we get multiple incremental maps at once.  Because check_pool_dne() can
now be fed an unlinked request, finish_request() needed to be taught to
handle unlinked requests.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

3 files changed, 27 insertions, 9 deletions

diff --git a/include/linux/ceph/osd_client.h b/include/linux/ceph/osd_client.h
index bca2718ac253..62c672bcbb31 100644
--- a/include/linux/ceph/osd_client.h
+++ b/include/linux/ceph/osd_client.h
@@ -149,6 +149,7 @@ struct ceph_osd_request_target {
         unsigned int flags;                /* CEPH_OSD_FLAG_* */
         bool paused;
 
+        u32 epoch;
         u32 last_force_resend;
 
         int osd;
diff --git a/net/ceph/debugfs.c b/net/ceph/debugfs.c
index 50ab1bdb16e2..c0089f8ccaeb 100644
--- a/net/ceph/debugfs.c
+++ b/net/ceph/debugfs.c
@@ -166,7 +166,7 @@ static void dump_target(struct seq_file *s, struct ceph_osd_request_target *t)
         seq_printf(s, "]/%d\t[", t->up.primary);
         for (i = 0; i < t->acting.size; i++)
                 seq_printf(s, "%s%d", (!i ? "" : ","), t->acting.osds[i]);
-        seq_printf(s, "]/%d\t", t->acting.primary);
+        seq_printf(s, "]/%d\te%u\t", t->acting.primary, t->epoch);
         if (t->target_oloc.pool_ns) {
                 seq_printf(s, "%*pE/%*pE\t0x%x",
                         (int)t->target_oloc.pool_ns->len,
diff --git a/net/ceph/osd_client.c b/net/ceph/osd_client.c
index 576101b635ef..173ab9c68eb6 100644
--- a/net/ceph/osd_client.c
+++ b/net/ceph/osd_client.c
@@ -386,6 +386,7 @@ static void target_copy(struct ceph_osd_request_target *dest,
         dest->flags = src->flags;
         dest->paused = src->paused;
 
+        dest->epoch = src->epoch;
         dest->last_force_resend = src->last_force_resend;
 
         dest->osd = src->osd;
@@ -1334,6 +1335,7 @@ static enum calc_target_result calc_target(struct ceph_osd_client *osdc,
         enum calc_target_result ct_res;
         int ret;
 
+        t->epoch = osdc->osdmap->epoch;
         pi = ceph_pg_pool_by_id(osdc->osdmap, t->base_oloc.pool);
         if (!pi) {
                 t->osd = CEPH_HOMELESS_OSD;
@@ -1720,10 +1722,11 @@ static void send_request(struct ceph_osd_request *req)
 
         encode_request_partial(req, req->r_request);
 
-        dout("%s req %p tid %llu to pgid %llu.%x spgid %llu.%xs%d osd%d flags 0x%x attempt %d\n",
+        dout("%s req %p tid %llu to pgid %llu.%x spgid %llu.%xs%d osd%d e%u flags 0x%x attempt %d\n",
              __func__, req, req->r_tid, req->r_t.pgid.pool, req->r_t.pgid.seed,
              req->r_t.spgid.pgid.pool, req->r_t.spgid.pgid.seed,
-             req->r_t.spgid.shard, osd->o_osd, req->r_flags, req->r_attempts);
+             req->r_t.spgid.shard, osd->o_osd, req->r_t.epoch, req->r_flags,
+             req->r_attempts);
 
         req->r_t.paused = false;
         req->r_stamp = jiffies;
@@ -1863,13 +1866,12 @@ static void submit_request(struct ceph_osd_request *req, bool wrlocked)
 static void finish_request(struct ceph_osd_request *req)
 {
         struct ceph_osd_client *osdc = req->r_osdc;
-        struct ceph_osd *osd = req->r_osd;
 
-        verify_osd_locked(osd);
+        WARN_ON(lookup_request_mc(&osdc->map_checks, req->r_tid));
         dout("%s req %p tid %llu\n", __func__, req, req->r_tid);
 
-        WARN_ON(lookup_request_mc(&osdc->map_checks, req->r_tid));
-        unlink_request(osd, req);
+        if (req->r_osd)
+                unlink_request(req->r_osd, req);
         atomic_dec(&osdc->num_requests);
 
         /*
@@ -3356,8 +3358,25 @@ static void kick_requests(struct ceph_osd_client *osdc,
                           struct list_head *need_resend_linger)
 {
         struct ceph_osd_linger_request *lreq, *nlreq;
+        enum calc_target_result ct_res;
         struct rb_node *n;
 
+        /* make sure need_resend targets reflect latest map */
+        for (n = rb_first(need_resend); n; ) {
+                struct ceph_osd_request *req =
+                    rb_entry(n, struct ceph_osd_request, r_node);
+
+                n = rb_next(n);
+
+                if (req->r_t.epoch < osdc->osdmap->epoch) {
+                        ct_res = calc_target(osdc, &req->r_t, NULL, false);
+                        if (ct_res == CALC_TARGET_POOL_DNE) {
+                                erase_request(need_resend, req);
+                                check_pool_dne(req);
+                        }
+                }
+        }
+
         for (n = rb_first(need_resend); n; ) {
                 struct ceph_osd_request *req =
                     rb_entry(n, struct ceph_osd_request, r_node);
@@ -3366,8 +3385,6 @@ static void kick_requests(struct ceph_osd_client *osdc,
                 n = rb_next(n);
                 erase_request(need_resend, req); /* before link_request() */
 
-                WARN_ON(req->r_osd);
-                calc_target(osdc, &req->r_t, NULL, false);
                 osd = lookup_create_osd(osdc, req->r_t.osd, true);
                 link_request(osd, req);
                 if (!req->r_linger) {