[PATCH] fs/pstore: constify pstore_zbackend structures

[PATCH] fs/pstore: constify pstore_zbackend structures

[Bhumika Goyal]

The references of pstore_zbackend structures are stored into the
pointer zbackend of type struct pstore_zbackend. The pointer zbackend
can be made const as it is only dereferenced. After making this change
the pstore_zbackend structures whose references are stored into the
pointer zbackend can be made const too.

File size before:
   text	   data	    bss	    dec	    hex	filename
   4817	    541	    172	   5530	   159a	fs/pstore/platform.o

File size after:
   text	   data	    bss	    dec	    hex	filename
   4865	    477	    172	   5514	   158a	fs/pstore/platform.o

Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
---
 fs/pstore/platform.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c
index 729677e..92e8728 100644
--- a/fs/pstore/platform.c
+++ b/fs/pstore/platform.c
@@ -267,7 +267,7 @@ static void free_zlib(void)
 	big_oops_buf_sz = 0;
 }
 
-static struct pstore_zbackend backend_zlib = {
+static const struct pstore_zbackend backend_zlib = {
 	.compress	= compress_zlib,
 	.decompress	= decompress_zlib,
 	.allocate	= allocate_zlib,
@@ -328,7 +328,7 @@ static void free_lzo(void)
 	big_oops_buf_sz = 0;
 }
 
-static struct pstore_zbackend backend_lzo = {
+static const struct pstore_zbackend backend_lzo = {
 	.compress	= compress_lzo,
 	.decompress	= decompress_lzo,
 	.allocate	= allocate_lzo,
@@ -389,7 +389,7 @@ static void free_lz4(void)
 	big_oops_buf_sz = 0;
 }
 
-static struct pstore_zbackend backend_lz4 = {
+static const struct pstore_zbackend backend_lz4 = {
 	.compress	= compress_lz4,
 	.decompress	= decompress_lz4,
 	.allocate	= allocate_lz4,
@@ -398,7 +398,7 @@ static void free_lz4(void)
 };
 #endif
 
-static struct pstore_zbackend *zbackend =
+static const struct pstore_zbackend *zbackend =
 #if defined(CONFIG_PSTORE_ZLIB_COMPRESS)
 	&backend_zlib;
 #elif defined(CONFIG_PSTORE_LZO_COMPRESS)
-- 
1.9.1

Re: [PATCH] fs/pstore: constify pstore_zbackend structures

[Kees Cook]

On Sun, Feb 19, 2017 at 1:37 AM, Bhumika Goyal <bhumirks@gmail.com> wrote:
> The references of pstore_zbackend structures are stored into the
> pointer zbackend of type struct pstore_zbackend. The pointer zbackend
> can be made const as it is only dereferenced. After making this change
> the pstore_zbackend structures whose references are stored into the
> pointer zbackend can be made const too.
>
> File size before:
>    text    data     bss     dec     hex filename
>    4817     541     172    5530    159a fs/pstore/platform.o
>
> File size after:
>    text    data     bss     dec     hex filename
>    4865     477     172    5514    158a fs/pstore/platform.o
>
> Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>

Awesome, thanks! I've applied this to my tree; it should be visible in
-next soon.

-Kees

-- 
Kees Cook
Pixel Security