[S390] drivers/s390: Eliminate NULL test and memset after alloc_bootmem

As noted by Akinobu Mita in patch b1fceac2b9e04d278316b2faddf276015fc06e3b,
alloc_bootmem and related functions never return NULL and always return a
zeroed region of memory.  Thus a NULL test or memset after calls to these
functions is unnecessary.

 drivers/s390/char/raw3270.c  |   11 +----------
 drivers/s390/char/sclp_con.c |    2 --
 2 files changed, 1 insertion(+), 12 deletions(-)

This was fixed using the following semantic patch.
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@@
expression E;
statement S;
@@

E = \(alloc_bootmem\|alloc_bootmem_low\|alloc_bootmem_pages\|alloc_bootmem_low_pages\)(...)
... when != E
(
- BUG_ON (E == NULL);
|
- if (E == NULL) S
)

@@
expression E,E1;
@@

E = \(alloc_bootmem\|alloc_bootmem_low\|alloc_bootmem_pages\|alloc_bootmem_low_pages\)(...)
... when != E
- memset(E,0,E1);
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

diff --git a/drivers/s390/char/raw3270.c b/drivers/s390/char/raw3270.c
index efce32e..e2767e3 100644 (file)
--- a/drivers/s390/char/raw3270.c
+++ b/drivers/s390/char/raw3270.c
@@ -153,19 +153,10 @@ struct raw3270_request __init *raw3270_request_alloc_bootmem(size_t size)
        struct raw3270_request *rq;
 
        rq = alloc_bootmem_low(sizeof(struct raw3270));
-       if (!rq)
-               return ERR_PTR(-ENOMEM);
-       memset(rq, 0, sizeof(struct raw3270_request));
 
        /* alloc output buffer. */
-       if (size > 0) {
+       if (size > 0)
                rq->buffer = alloc_bootmem_low(size);
-               if (!rq->buffer) {
-                       free_bootmem((unsigned long) rq,
-                                    sizeof(struct raw3270));
-                       return ERR_PTR(-ENOMEM);
-               }
-       }
        rq->size = size;
        INIT_LIST_HEAD(&rq->list);
 

diff --git a/drivers/s390/char/sclp_con.c b/drivers/s390/char/sclp_con.c
index ead1043..23bb90a 100644 (file)
--- a/drivers/s390/char/sclp_con.c
+++ b/drivers/s390/char/sclp_con.c
@@ -222,8 +222,6 @@ sclp_console_init(void)
        INIT_LIST_HEAD(&sclp_con_pages);
        for (i = 0; i < MAX_CONSOLE_PAGES; i++) {
                page = alloc_bootmem_low_pages(PAGE_SIZE);
-               if (page == NULL)
-                       return -ENOMEM;
                list_add_tail((struct list_head *) page, &sclp_con_pages);
        }
        INIT_LIST_HEAD(&sclp_con_outqueue);