ocfs2: Better I/O error handling in heartbeat

Propagate errors received in o2hb_bio_end_io() back to the heartbeat thread
so it can skip re-arming the timer.

Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>

diff --git a/fs/ocfs2/cluster/heartbeat.c b/fs/ocfs2/cluster/heartbeat.c
index bff0f0d06867f12c282111c948274a80bfc188c2..21f38accd0399dd26f6fa1da70af16209c01469e 100644 (file)
--- a/fs/ocfs2/cluster/heartbeat.c
+++ b/fs/ocfs2/cluster/heartbeat.c
@@ -153,6 +153,7 @@ struct o2hb_region {
 struct o2hb_bio_wait_ctxt {
        atomic_t          wc_num_reqs;
        struct completion wc_io_complete;
+       int               wc_error;
 };
 
 static void o2hb_write_timeout(void *arg)
@@ -186,6 +187,7 @@ static inline void o2hb_bio_wait_init(struct o2hb_bio_wait_ctxt *wc,
 {
        atomic_set(&wc->wc_num_reqs, num_ios);
        init_completion(&wc->wc_io_complete);
+       wc->wc_error = 0;
 }
 
 /* Used in error paths too */
@@ -218,8 +220,10 @@ static int o2hb_bio_end_io(struct bio *bio,
 {
        struct o2hb_bio_wait_ctxt *wc = bio->bi_private;
 
-       if (error)
+       if (error) {
                mlog(ML_ERROR, "IO Error %d\n", error);
+               wc->wc_error = error;
+       }
 
        if (bio->bi_size)
                return 1;
@@ -390,6 +394,8 @@ static int o2hb_read_slots(struct o2hb_region *reg,
 
 bail_and_wait:
        o2hb_wait_on_io(reg, &wc);
+       if (wc.wc_error && !status)
+               status = wc.wc_error;
 
        if (bios) {
                for(i = 0; i < num_bios; i++)
@@ -790,20 +796,24 @@ static int o2hb_highest_node(unsigned long *nodes,
        return highest;
 }
 
-static void o2hb_do_disk_heartbeat(struct o2hb_region *reg)
+static int o2hb_do_disk_heartbeat(struct o2hb_region *reg)
 {
        int i, ret, highest_node, change = 0;
        unsigned long configured_nodes[BITS_TO_LONGS(O2NM_MAX_NODES)];
        struct bio *write_bio;
        struct o2hb_bio_wait_ctxt write_wc;
 
-       if (o2nm_configured_node_map(configured_nodes, sizeof(configured_nodes)))
-               return;
+       ret = o2nm_configured_node_map(configured_nodes,
+                                      sizeof(configured_nodes));
+       if (ret) {
+               mlog_errno(ret);
+               return ret;
+       }
 
        highest_node = o2hb_highest_node(configured_nodes, O2NM_MAX_NODES);
        if (highest_node >= O2NM_MAX_NODES) {
                mlog(ML_NOTICE, "ocfs2_heartbeat: no configured nodes found!\n");
-               return;
+               return -EINVAL;
        }
 
        /* No sense in reading the slots of nodes that don't exist
@@ -813,7 +823,7 @@ static void o2hb_do_disk_heartbeat(struct o2hb_region *reg)
        ret = o2hb_read_slots(reg, highest_node + 1);
        if (ret < 0) {
                mlog_errno(ret);
-               return;
+               return ret;
        }
 
        /* With an up to date view of the slots, we can check that no
@@ -831,7 +841,7 @@ static void o2hb_do_disk_heartbeat(struct o2hb_region *reg)
        ret = o2hb_issue_node_write(reg, &write_bio, &write_wc);
        if (ret < 0) {
                mlog_errno(ret);
-               return;
+               return ret;
        }
 
        i = -1;
@@ -847,6 +857,15 @@ static void o2hb_do_disk_heartbeat(struct o2hb_region *reg)
         */
        o2hb_wait_on_io(reg, &write_wc);
        bio_put(write_bio);
+       if (write_wc.wc_error) {
+               /* Do not re-arm the write timeout on I/O error - we
+                * can't be sure that the new block ever made it to
+                * disk */
+               mlog(ML_ERROR, "Write error %d on device \"%s\"\n",
+                    write_wc.wc_error, reg->hr_dev_name);
+               return write_wc.wc_error;
+       }
+
        o2hb_arm_write_timeout(reg);
 
        /* let the person who launched us know when things are steady */
@@ -854,6 +873,8 @@ static void o2hb_do_disk_heartbeat(struct o2hb_region *reg)
                if (atomic_dec_and_test(&reg->hr_steady_iterations))
                        wake_up(&o2hb_steady_queue);
        }
+
+       return 0;
 }
 
 /* Subtract b from a, storing the result in a. a *must* have a larger
@@ -913,7 +934,10 @@ static int o2hb_thread(void *data)
                 * likely to time itself out. */
                do_gettimeofday(&before_hb);
 
-               o2hb_do_disk_heartbeat(reg);
+               i = 0;
+               do {
+                       ret = o2hb_do_disk_heartbeat(reg);
+               } while (ret && ++i < 2);
 
                do_gettimeofday(&after_hb);
                elapsed_msec = o2hb_elapsed_msecs(&before_hb, &after_hb);