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To: linux-kernel@vger.kernel.org
From: JAILLET Christophe <jaillet.christophe@wanadoo.fr>
Subject: [PATCH 1/1] drivers/media/video/videobuf-dma-sg.c: avoid to clear
 memory twice
Date: Mon, 09 Jun 2008 00:08:00 +0200
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From: Christophe Jaillet <jaillet.christophe@wanadoo.fr>

Hi, here is a patch against linux/drivers/usb/atm/cxacru.c which :

1) Remove a useless initialisation of 'i'
2) Avoid to clear the memory allocated twice (once in 'kcalloc', once in 
'sg_init_table')
3) Remove a test that can never trigger. The function returns NULL in 
such a case, so we know that at this point 'pages[0]' != NULL


Signed-off-by: Christophe Jaillet <jaillet.christophe@wanadoo.fr>

---

diff --git a/drivers/media/video/videobuf-dma-sg.c
b/drivers/media/video/videobuf-dma-sg.c
index 03a7b94..8ed6082 100644
--- a/drivers/media/video/videobuf-dma-sg.c
+++ b/drivers/media/video/videobuf-dma-sg.c
@@ -80,17 +80,15 @@ struct scatterlist*
  videobuf_pages_to_sg(struct page **pages, int nr_pages, int offset)
  {
         struct scatterlist *sglist;
-       int i = 0;
+       int i;

         if (NULL == pages[0])
                 return NULL;
-       sglist = kcalloc(nr_pages, sizeof(*sglist), GFP_KERNEL);
+       sglist = kmalloc(nr_pages * sizeof(*sglist), GFP_KERNEL);
         if (NULL == sglist)
                 return NULL;
         sg_init_table(sglist, nr_pages);

-       if (NULL == pages[0])
-               goto nopage;
         if (PageHighMem(pages[0]))
                 /* DMA to highmem pages might not work */
                 goto highmem;