From: John Garry <john.garry@huawei.com>
Date: Fri, 25 Jan 2019 22:22:27 +0800
Subject: scsi: hisi_sas: No need to check return value of debugfs_create
 functions
Patch-mainline: v5.1-rc1
Git-commit: c2c7e740577154e755ec373712e32e5864e88315
References: bsc#1140683

When calling debugfs functions, there is no need to ever check the return
value. The function can work or not, but the code logic should never do
something different based on this.

Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Daniel Wagner <dwagner@suse.de>
---
 drivers/scsi/hisi_sas/hisi_sas.h      |    1 
 drivers/scsi/hisi_sas/hisi_sas_main.c |   53 ++++++++++------------------------
 2 files changed, 17 insertions(+), 37 deletions(-)

--- a/drivers/scsi/hisi_sas/hisi_sas.h
+++ b/drivers/scsi/hisi_sas/hisi_sas.h
@@ -368,6 +368,7 @@ struct hisi_hba {
 
 	struct dentry *debugfs_dir;
 	struct dentry *debugfs_dump_dentry;
+	bool debugfs_snapshot;
 };
 
 /* Generic HW DMA host memory structures */
--- a/drivers/scsi/hisi_sas/hisi_sas_main.c
+++ b/drivers/scsi/hisi_sas/hisi_sas_main.c
@@ -1429,8 +1429,7 @@ static int hisi_sas_controller_reset(str
 	struct Scsi_Host *shost = hisi_hba->shost;
 	int rc;
 
-	if (hisi_sas_debugfs_enable && hisi_hba->debugfs_itct &&
-	    !hisi_hba->debugfs_dump_dentry)
+	if (hisi_sas_debugfs_enable && hisi_hba->debugfs_itct)
 		queue_work(hisi_hba->wq, &hisi_hba->debugfs_work);
 
 	if (!hisi_hba->hw->soft_reset)
@@ -2784,63 +2783,42 @@ static void hisi_sas_debugfs_create_file
 
 	/* Create dump dir inside device dir */
 	dump_dentry = debugfs_create_dir("dump", hisi_hba->debugfs_dir);
-	if (!dump_dentry)
-		goto fail;
-
 	hisi_hba->debugfs_dump_dentry = dump_dentry;
 
-	if (!debugfs_create_file("global", 0400, dump_dentry, hisi_hba,
-				 &hisi_sas_debugfs_global_fops))
-		goto fail;
+	debugfs_create_file("global", 0400, dump_dentry, hisi_hba,
+			    &hisi_sas_debugfs_global_fops);
 
 	/* Create port dir and files */
 	dentry = debugfs_create_dir("port", dump_dentry);
-	if (!dentry)
-		goto fail;
-
 	for (p = 0; p < hisi_hba->n_phy; p++) {
 		snprintf(name, 256, "%d", p);
-		if (!debugfs_create_file(name, 0400, dentry,
-					 &hisi_hba->phy[p],
-					 &hisi_sas_debugfs_port_fops))
-			goto fail;
+
+		debugfs_create_file(name, 0400, dentry, &hisi_hba->phy[p],
+				    &hisi_sas_debugfs_port_fops);
 	}
 
 	/* Create CQ dir and files */
 	dentry = debugfs_create_dir("cq", dump_dentry);
-	if (!dentry)
-		goto fail;
-
 	for (c = 0; c < hisi_hba->queue_count; c++) {
 		snprintf(name, 256, "%d", c);
 
-		if (!debugfs_create_file(name, 0400, dentry,
-					 &hisi_hba->cq[c],
-					 &hisi_sas_debugfs_cq_fops))
-			goto fail;
+		debugfs_create_file(name, 0400, dentry, &hisi_hba->cq[c],
+				    &hisi_sas_debugfs_cq_fops);
 	}
 
 	/* Create DQ dir and files */
 	dentry = debugfs_create_dir("dq", dump_dentry);
-	if (!dentry)
-		goto fail;
-
 	for (d = 0; d < hisi_hba->queue_count; d++) {
 		snprintf(name, 256, "%d", d);
 
-		if (!debugfs_create_file(name, 0400, dentry,
-					 &hisi_hba->dq[d],
-					 &hisi_sas_debugfs_dq_fops))
-			goto fail;
+		debugfs_create_file(name, 0400, dentry, &hisi_hba->dq[d],
+				    &hisi_sas_debugfs_dq_fops);
 	}
 
-	if (!debugfs_create_file("iost", 0400, dump_dentry, hisi_hba,
-				 &hisi_sas_debugfs_iost_fops))
-		goto fail;
+	debugfs_create_file("iost", 0400, dump_dentry, hisi_hba,
+			    &hisi_sas_debugfs_iost_fops);
 
 	return;
-fail:
-	debugfs_remove_recursive(hisi_hba->debugfs_dir);
 }
 
 static void hisi_sas_debugfs_snapshot_regs(struct hisi_hba *hisi_hba)
@@ -2864,6 +2842,10 @@ void hisi_sas_debugfs_work_handler(struc
 	struct hisi_hba *hisi_hba =
 		container_of(work, struct hisi_hba, debugfs_work);
 
+	if (hisi_hba->debugfs_snapshot)
+		return;
+	hisi_hba->debugfs_snapshot = true;
+
 	hisi_sas_debugfs_snapshot_regs(hisi_hba);
 }
 EXPORT_SYMBOL_GPL(hisi_sas_debugfs_work_handler);
@@ -2878,9 +2860,6 @@ void hisi_sas_debugfs_init(struct hisi_h
 	hisi_hba->debugfs_dir = debugfs_create_dir(dev_name(dev),
 						   hisi_sas_debugfs_dir);
 
-	if (!hisi_hba->debugfs_dir)
-		return;
-
 	/* Alloc buffer for global */
 	sz = hisi_hba->hw->debugfs_reg_global->count * 4;
 	hisi_hba->debugfs_global_reg =