Fix missing 'zpool events'

[zfs.git] / module / zfs / fm.c

diff --git a/module/zfs/fm.c b/module/zfs/fm.c
index 67d0c1a..d409b29 100644 (file)
--- a/module/zfs/fm.c
+++ b/module/zfs/fm.c
@@ -568,13 +568,18 @@ zfs_zevent_fd_rele(int fd)
 }
 
 /*
- * Get the next zevent in the stream and place a copy in 'event'.
+ * Get the next zevent in the stream and place a copy in 'event'.  This
+ * may fail with ENOMEM if the encoded nvlist size exceeds the passed
+ * 'event_size'.  In this case the stream pointer is not advanced and
+ * and 'event_size' is set to the minimum required buffer size.
  */
 int
-zfs_zevent_next(zfs_zevent_t *ze, nvlist_t **event, uint64_t *dropped)
+zfs_zevent_next(zfs_zevent_t *ze, nvlist_t **event, uint64_t *event_size,
+                uint64_t *dropped)
 {
        zevent_t *ev;
-       int error;
+       size_t size;
+       int error = 0;
 
        mutex_enter(&zevent_lock);
        if (ze->ze_zevent == NULL) {
@@ -592,10 +597,18 @@ zfs_zevent_next(zfs_zevent_t *ze, nvlist_t **event, uint64_t *dropped)
                        error = ENOENT;
                        goto out;
                }
+       }
 
-               list_remove(&ze->ze_zevent->ev_ze_list, ze);
+       VERIFY(nvlist_size(ev->ev_nvl, &size, NV_ENCODE_NATIVE) == 0);
+       if (size > *event_size) {
+               *event_size = size;
+               error = ENOMEM;
+               goto out;
        }
 
+       if (ze->ze_zevent)
+               list_remove(&ze->ze_zevent->ev_ze_list, ze);
+
        ze->ze_zevent = ev;
        list_insert_head(&ev->ev_ze_list, ze);
        nvlist_dup(ev->ev_nvl, event, KM_SLEEP);