drbd: Fixed logging of old connection state

During a disconnect the oc variable in _conn_request_state()
could become outdated. Determin the common old state after
sleeping.
While at it, I implemented that for all parts of the state

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>

1 files changed, 87 insertions, 30 deletions

diff --git a/drivers/block/drbd/drbd_state.c b/drivers/block/drbd/drbd_state.c
index 85cfbeadd513..2a170bf7cc29 100644
--- a/drivers/block/drbd/drbd_state.c
+++ b/drivers/block/drbd/drbd_state.c
@@ -1377,42 +1377,100 @@ static void print_conn_state_change(struct drbd_tconn *tconn, enum drbd_conns oc
         conn_info(tconn, "%s\n", pb);
 }
 
-struct _is_valid_itr_params {
-        enum drbd_conns oc;
-        enum {
-                OC_UNINITIALIZED,
-                OC_CONSISTENT,
-                OC_INCONSISTENT,
-        } oc_state;
-};
+enum sp_state {
+        OC_UNINITIALIZED,
+        OC_CONSISTENT,
+        OC_INCONSISTENT,
+} oc_state;
+
+static void common_state_part(enum sp_state *sps, int *sp, int nsp)
+{
+        switch (*sps) {
+        case OC_UNINITIALIZED:
+                *sp = nsp;
+                *sps = OC_CONSISTENT;
+                break;
+        case OC_CONSISTENT:
+                if (*sp != nsp)
+                        *sps = OC_INCONSISTENT;
+                break;
+        case OC_INCONSISTENT:
+                break;
+        }
+}
+
+void conn_old_common_state(struct drbd_tconn *tconn, union drbd_state *pcs, union drbd_state *pmask)
+{
+        union drbd_state css = {}; /* common state state */
+        union drbd_state os, cs = {}; /* old_state, common_state */
+        union drbd_state mask = {};
+        enum sp_state sps;       /* state part state */
+        int sp;                  /* state part */
+        struct drbd_conf *mdev;
+        int vnr;
+
+        idr_for_each_entry(&tconn->volumes, mdev, vnr) {
+                os = mdev->state;
+
+                sps = css.role;
+                sp = cs.role;
+                common_state_part(&sps, &sp, os.role);
+                css.role = sps;
+                cs.role = sp;
+
+                sps = css.peer;
+                sp = cs.peer;
+                common_state_part(&sps, &sp, os.peer);
+                css.peer = sps;
+                cs.peer = sp;
+
+                sps = css.conn;
+                sp = cs.conn;
+                common_state_part(&sps, &sp, os.conn);
+                css.conn = sps;
+                cs.conn = sp;
+
+                sps = css.disk;
+                sp = cs.disk;
+                common_state_part(&sps, &sp, os.disk);
+                css.disk = sps;
+                cs.disk = sp;
+
+                sps = css.pdsk;
+                sp = cs.pdsk;
+                common_state_part(&sps, &sp, os.pdsk);
+                css.pdsk = sps;
+                cs.pdsk = sp;
+        }
+
+        if (css.role == OC_CONSISTENT)
+                mask.role = R_MASK;
+        if (css.peer == OC_CONSISTENT)
+                mask.peer = R_MASK;
+        if (css.conn == OC_CONSISTENT)
+                mask.conn = C_MASK;
+        if (css.disk == OC_CONSISTENT)
+                mask.disk = D_MASK;
+        if (css.pdsk == OC_CONSISTENT)
+                mask.pdsk = D_MASK;
+
+        *pcs = cs;
+        *pmask = mask;
+}
 
 static enum drbd_state_rv
 conn_is_valid_transition(struct drbd_tconn *tconn, union drbd_state mask, union drbd_state val,
-                         enum chg_state_flags flags, struct _is_valid_itr_params *params)
+                         enum chg_state_flags flags)
 {
         enum drbd_state_rv rv = SS_SUCCESS;
         union drbd_state ns, os;
         struct drbd_conf *mdev;
         int vnr;
 
-        params->oc_state = OC_UNINITIALIZED;
         idr_for_each_entry(&tconn->volumes, mdev, vnr) {
                 os = mdev->state;
                 ns = sanitize_state(mdev, apply_mask_val(os, mask, val), NULL);
 
-                switch (params->oc_state) {
-                case OC_UNINITIALIZED:
-                        params->oc = os.conn;
-                        params->oc_state = OC_CONSISTENT;
-                        break;
-                case OC_CONSISTENT:
-                        if (params->oc != os.conn)
-                                params->oc_state = OC_INCONSISTENT;
-                        break;
-                case OC_INCONSISTENT:
-                        break;
-                }
-
                 if (ns.i == os.i)
                         continue;
 
@@ -1471,7 +1529,6 @@ conn_set_state(struct drbd_tconn *tconn, union drbd_state mask, union drbd_state
 static enum drbd_state_rv
 _conn_rq_cond(struct drbd_tconn *tconn, union drbd_state mask, union drbd_state val)
 {
-        struct _is_valid_itr_params params;
         enum drbd_state_rv rv;
 
         if (test_and_clear_bit(CONN_WD_ST_CHG_OKAY, &tconn->flags))
@@ -1484,7 +1541,7 @@ _conn_rq_cond(struct drbd_tconn *tconn, union drbd_state mask, union drbd_state
         rv = tconn->cstate != C_WF_REPORT_PARAMS ? SS_CW_NO_NEED : SS_UNKNOWN_ERROR;
 
         if (rv == SS_UNKNOWN_ERROR)
-                rv = conn_is_valid_transition(tconn, mask, val, CS_NO_CSTATE_CHG, &params);
+                rv = conn_is_valid_transition(tconn, mask, val, CS_NO_CSTATE_CHG);
 
         if (rv == SS_SUCCESS)
                 rv = SS_UNKNOWN_ERROR; /* cont waiting, otherwise fail. */
@@ -1524,16 +1581,15 @@ _conn_request_state(struct drbd_tconn *tconn, union drbd_state mask, union drbd_
                     enum chg_state_flags flags)
 {
         enum drbd_state_rv rv = SS_SUCCESS;
-        struct _is_valid_itr_params params;
         struct after_conn_state_chg_work *acscw;
         enum drbd_conns oc = tconn->cstate;
-        union drbd_state ms;
+        union drbd_state ms, os_val, os_mask;
 
         rv = is_valid_conn_transition(oc, val.conn);
         if (rv < SS_SUCCESS)
                 goto abort;
 
-        rv = conn_is_valid_transition(tconn, mask, val, flags, &params);
+        rv = conn_is_valid_transition(tconn, mask, val, flags);
         if (rv < SS_SUCCESS)
                 goto abort;
 
@@ -1544,8 +1600,9 @@ _conn_request_state(struct drbd_tconn *tconn, union drbd_state mask, union drbd_
                         goto abort;
         }
 
-        if (params.oc_state == OC_CONSISTENT) {
-                oc = params.oc;
+        conn_old_common_state(tconn, &os_val, &os_mask);
+        if (os_mask.conn == C_MASK) {
+                oc = os_val.conn;
                 print_conn_state_change(tconn, oc, val.conn);
                 flags |= CS_NO_CSTATE_CHG;
         }