s390/dasd: Remove unnecessary debugfs_create() return checks

The DASD driver only uses the dentry pointers when removing debugfs
entries, and debugfs_remove() can safely handle both NULL and ERR_PTR.
There is therefore no need to check debugfs_create() return values.

This simplifies the debugfs setup code without changing functionality.

Suggested-by: Heiko Carstens <hca@linux.ibm.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Reviewed-by: Jan Hoeppner <hoeppner@linux.ibm.com>
Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/drivers/s390/block/dasd.c b/drivers/s390/block/dasd.c
index 7765e40f7ceac03c22ca6f3605f5bfe12b5f16c3..496f95745adea07fb71a30acffa3b2667cd1e38e 100644 (file)
--- a/drivers/s390/block/dasd.c
+++ b/drivers/s390/block/dasd.c
@@ -207,19 +207,6 @@ static int dasd_state_known_to_new(struct dasd_device *device)
        return 0;
 }
 
-static struct dentry *dasd_debugfs_setup(const char *name,
-                                        struct dentry *base_dentry)
-{
-       struct dentry *pde;
-
-       if (!base_dentry)
-               return NULL;
-       pde = debugfs_create_dir(name, base_dentry);
-       if (!pde || IS_ERR(pde))
-               return NULL;
-       return pde;
-}
-
 /*
  * Request the irq line for the device.
  */
@@ -234,14 +221,14 @@ static int dasd_state_known_to_basic(struct dasd_device *device)
                if (rc)
                        return rc;
                block->debugfs_dentry =
-                       dasd_debugfs_setup(block->gdp->disk_name,
+                       debugfs_create_dir(block->gdp->disk_name,
                                           dasd_debugfs_root_entry);
                dasd_profile_init(&block->profile, block->debugfs_dentry);
                if (dasd_global_profile_level == DASD_PROFILE_ON)
                        dasd_profile_on(&device->block->profile);
        }
        device->debugfs_dentry =
-               dasd_debugfs_setup(dev_name(&device->cdev->dev),
+               debugfs_create_dir(dev_name(&device->cdev->dev),
                                   dasd_debugfs_root_entry);
        dasd_profile_init(&device->profile, device->debugfs_dentry);
        dasd_hosts_init(device->debugfs_dentry, device);
@@ -1058,19 +1045,9 @@ static const struct file_operations dasd_stats_raw_fops = {
 static void dasd_profile_init(struct dasd_profile *profile,
                              struct dentry *base_dentry)
 {
-       umode_t mode;
-       struct dentry *pde;
-
-       if (!base_dentry)
-               return;
-       profile->dentry = NULL;
        profile->data = NULL;
-       mode = (S_IRUSR | S_IWUSR | S_IFREG);
-       pde = debugfs_create_file("statistics", mode, base_dentry,
-                                 profile, &dasd_stats_raw_fops);
-       if (pde && !IS_ERR(pde))
-               profile->dentry = pde;
-       return;
+       profile->dentry = debugfs_create_file("statistics", 0600, base_dentry,
+                                             profile, &dasd_stats_raw_fops);
 }
 
 static void dasd_profile_exit(struct dasd_profile *profile)
@@ -1090,25 +1067,9 @@ static void dasd_statistics_removeroot(void)
 
 static void dasd_statistics_createroot(void)
 {
-       struct dentry *pde;
-
-       dasd_debugfs_root_entry = NULL;
-       pde = debugfs_create_dir("dasd", NULL);
-       if (!pde || IS_ERR(pde))
-               goto error;
-       dasd_debugfs_root_entry = pde;
-       pde = debugfs_create_dir("global", dasd_debugfs_root_entry);
-       if (!pde || IS_ERR(pde))
-               goto error;
-       dasd_debugfs_global_entry = pde;
+       dasd_debugfs_root_entry = debugfs_create_dir("dasd", NULL);
+       dasd_debugfs_global_entry = debugfs_create_dir("global", dasd_debugfs_root_entry);
        dasd_profile_init(&dasd_global_profile, dasd_debugfs_global_entry);
-       return;
-
-error:
-       DBF_EVENT(DBF_ERR, "%s",
-                 "Creation of the dasd debugfs interface failed");
-       dasd_statistics_removeroot();
-       return;
 }
 
 #else
@@ -1169,17 +1130,8 @@ static void dasd_hosts_exit(struct dasd_device *device)
 static void dasd_hosts_init(struct dentry *base_dentry,
                            struct dasd_device *device)
 {
-       struct dentry *pde;
-       umode_t mode;
-
-       if (!base_dentry)
-               return;
-
-       mode = S_IRUSR | S_IFREG;
-       pde = debugfs_create_file("host_access_list", mode, base_dentry,
-                                 device, &dasd_hosts_fops);
-       if (pde && !IS_ERR(pde))
-               device->hosts_dentry = pde;
+       device->hosts_dentry = debugfs_create_file("host_access_list", 0400, base_dentry,
+                                                  device, &dasd_hosts_fops);
 }
 
 struct dasd_ccw_req *dasd_smalloc_request(int magic, int cplength, int datasize,