Jul 19 2009

USB: storage: Drop an unneeded a NULL test 

Author: Julia Lawall <julia@diku.dk>

In each case, the NULL test is not necessary because the function is static
and at the only places where it is called, the us argument has already been
dereferenced.

The semantic patch that finds the problem is as follows:
(http://www.emn.fr/x-info/coccinelle/)

// 
@@
type T;
expression E,E1;
identifier i,fld;
statement S;
@@

- T i = E->fld;
+ T i;
  ... when != E=E1
      when != i
  if (E == NULL||...) S
+ i = E->fld;
// 

Signed-off-by: Julia Lawall 
Cc: Matthew Dharm 
Cc: Alan Stern 
Signed-off-by: Greg Kroah-Hartman 


---
 drivers/usb/storage/datafab.c  | 4 ++--
 drivers/usb/storage/jumpshot.c | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)
 
diff --git a/drivers/usb/storage/datafab.c b/drivers/usb/storage/datafab.c
index 2b6e565..ded836b 100644
--- a/drivers/usb/storage/datafab.c
+++ b/drivers/usb/storage/datafab.c
@@ -334,7 +334,7 @@ static int datafab_determine_lun(struct us_data *us,
 	unsigned char *buf;
 	int count = 0, rc;
 
-	if (!us || !info)
+	if (!info)
 		return USB_STOR_TRANSPORT_ERROR;
 
 	memcpy(command, scommand, 8);
@@ -399,7 +399,7 @@ static int datafab_id_device(struct us_data *us,
 	unsigned char *reply;
 	int rc;
 
-	if (!us || !info)
+	if (!info)
 		return USB_STOR_TRANSPORT_ERROR;
 
 	if (info->lun == -1) {
diff --git a/drivers/usb/storage/jumpshot.c b/drivers/usb/storage/jumpshot.c
index 1c69420..6168596 100644
--- a/drivers/usb/storage/jumpshot.c
+++ b/drivers/usb/storage/jumpshot.c
@@ -335,7 +335,7 @@ static int jumpshot_id_device(struct us_data *us,
 	unsigned char *reply;
 	int 	 rc;
 
-	if (!us || !info)
+	if (!info)
 		return USB_STOR_TRANSPORT_ERROR;
 
 	command[0] = 0xE0;

qlambert