Commit 3ca1c990 authored Jul 14, 2008 by Julia Lawall Committed by Heiko Carstens Jul 14, 2008

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

As noted by Akinobu Mita in patch b1fceac2,
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>

parent 402a3998

drivers/s390/char/raw3270.c

+1 −10

Original line number	Diff line number	Diff line
		@@ -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);

drivers/s390/char/sclp_con.c

+0 −2

Original line number	Diff line number	Diff line
		@@ -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);