If IO submission fails, assert that the cause can be fixed by waiting

src/fellow_log.c

@@ -1732,7 +1732,7 @@ fellow_logblk_commit(struct fellow_disk_log_block *logblk)
 }
 
 // XXX error handling
-static int
+static unsigned
 fellow_io_log_submit(const struct fellow_fd *ffd, void *ioctx,
     enum fellow_aio_info_type type, struct fellow_alloc_log_block *blk)
 {
@@ -2193,14 +2193,14 @@ logbuffer_ref(struct fellow_fd *ffd, const struct fellow_logbuffer *lbuf)
 }
 
 // avoid code duplication
-static int
+static unsigned
 flush_active(struct fellow_fd *ffd, struct fellow_logbuffer *lbuf,
     unsigned opts)
 {
 	struct fellow_alloc_log_block blk;
 	struct fellow_disk_log_block *copy = NULL;
 	enum fellow_aio_info_type type;
-	int r;
+	unsigned r;
 
 	AN(lbuf->fdil.ioctx);
 	AN(lbuf->active.off);
@@ -2296,9 +2296,8 @@ logbuffer_flush(struct fellow_fd *ffd,
 	struct fellow_alloc_log_block **arr;
 	const struct stvfe_tune *tune;
 	struct buddy_ptr_extent mem;
-	unsigned u, v, n;
+	unsigned r, u, v, n;
 	size_t sz;
-	int r;
 
 	CHECK_OBJ_NOTNULL(ffd, FELLOW_FD_MAGIC);
 	tune = ffd->tune;
@@ -2593,9 +2592,11 @@ logbuffer_flush(struct fellow_fd *ffd,
 		lbuf->flush_seq = arr[u]->block->entry[0].seq;
 		u--;
 
-		v += fellow_io_log_wait_completions(
+		r = fellow_io_log_wait_completions(
 		    lbuf->membuddy,
 		    lbuf->fdil.ioctx, 1);
+		AN(r);
+		v += r;
 		FDBG(D_LOG_FLUSH, "submit full complete %u", v);
 	}