1 files changed, 18 insertions, 64 deletions

diff --git a/drivers/s390/scsi/zfcp_aux.c b/drivers/s390/scsi/zfcp_aux.c
index 94f4d8fe85e0..9cf30d124b9e 100644
--- a/drivers/s390/scsi/zfcp_aux.c
+++ b/drivers/s390/scsi/zfcp_aux.c
@@ -4,7 +4,7 @@
  *
  * Module interface and handling of zfcp data structures.
  *
- * Copyright IBM Corp. 2002, 2013
+ * Copyright IBM Corp. 2002, 2017
  */
 
 /*
@@ -124,6 +124,9 @@ static int __init zfcp_module_init(void)
 {
 	int retval = -ENOMEM;
 
+	if (zfcp_experimental_dix)
+		pr_warn("DIX is enabled. It is experimental and might cause problems\n");
+
 	zfcp_fsf_qtcb_cache = zfcp_cache_hw_align("zfcp_fsf_qtcb",
 						  sizeof(struct fsf_qtcb));
 	if (!zfcp_fsf_qtcb_cache)
@@ -248,43 +251,36 @@ static int zfcp_allocate_low_mem_buffers(struct zfcp_adapter *adapter)
 
 static void zfcp_free_low_mem_buffers(struct zfcp_adapter *adapter)
 {
-	if (adapter->pool.erp_req)
-		mempool_destroy(adapter->pool.erp_req);
-	if (adapter->pool.scsi_req)
-		mempool_destroy(adapter->pool.scsi_req);
-	if (adapter->pool.scsi_abort)
-		mempool_destroy(adapter->pool.scsi_abort);
-	if (adapter->pool.qtcb_pool)
-		mempool_destroy(adapter->pool.qtcb_pool);
-	if (adapter->pool.status_read_req)
-		mempool_destroy(adapter->pool.status_read_req);
-	if (adapter->pool.sr_data)
-		mempool_destroy(adapter->pool.sr_data);
-	if (adapter->pool.gid_pn)
-		mempool_destroy(adapter->pool.gid_pn);
+	mempool_destroy(adapter->pool.erp_req);
+	mempool_destroy(adapter->pool.scsi_req);
+	mempool_destroy(adapter->pool.scsi_abort);
+	mempool_destroy(adapter->pool.qtcb_pool);
+	mempool_destroy(adapter->pool.status_read_req);
+	mempool_destroy(adapter->pool.sr_data);
+	mempool_destroy(adapter->pool.gid_pn);
 }
 
 /**
  * zfcp_status_read_refill - refill the long running status_read_requests
  * @adapter: ptr to struct zfcp_adapter for which the buffers should be refilled
  *
- * Returns: 0 on success, 1 otherwise
- *
- * if there are 16 or more status_read requests missing an adapter_reopen
- * is triggered
+ * Return:
+ * * 0 on success meaning at least one status read is pending
+ * * 1 if posting failed and not a single status read buffer is pending,
+ *     also triggers adapter reopen recovery
  */
 int zfcp_status_read_refill(struct zfcp_adapter *adapter)
 {
-	while (atomic_read(&adapter->stat_miss) > 0)
+	while (atomic_add_unless(&adapter->stat_miss, -1, 0))
 		if (zfcp_fsf_status_read(adapter->qdio)) {
+			atomic_inc(&adapter->stat_miss); /* undo add -1 */
 			if (atomic_read(&adapter->stat_miss) >=
 			    adapter->stat_read_buf_num) {
 				zfcp_erp_adapter_reopen(adapter, 0, "axsref1");
 				return 1;
 			}
 			break;
-		} else
-			atomic_dec(&adapter->stat_miss);
+		}
 	return 0;
 }
 
@@ -542,45 +538,3 @@ err_out:
 	zfcp_ccw_adapter_put(adapter);
 	return ERR_PTR(retval);
 }
-
-/**
- * zfcp_sg_free_table - free memory used by scatterlists
- * @sg: pointer to scatterlist
- * @count: number of scatterlist which are to be free'ed
- * the scatterlist are expected to reference pages always
- */
-void zfcp_sg_free_table(struct scatterlist *sg, int count)
-{
-	int i;
-
-	for (i = 0; i < count; i++, sg++)
-		if (sg)
-			free_page((unsigned long) sg_virt(sg));
-		else
-			break;
-}
-
-/**
- * zfcp_sg_setup_table - init scatterlist and allocate, assign buffers
- * @sg: pointer to struct scatterlist
- * @count: number of scatterlists which should be assigned with buffers
- * of size page
- *
- * Returns: 0 on success, -ENOMEM otherwise
- */
-int zfcp_sg_setup_table(struct scatterlist *sg, int count)
-{
-	void *addr;
-	int i;
-
-	sg_init_table(sg, count);
-	for (i = 0; i < count; i++, sg++) {
-		addr = (void *) get_zeroed_page(GFP_KERNEL);
-		if (!addr) {
-			zfcp_sg_free_table(sg, i);
-			return -ENOMEM;
-		}
-		sg_set_buf(sg, addr, PAGE_SIZE);
-	}
-	return 0;
-}