lkml.org 
[lkml]   [2011]   [Oct]   [13]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH] mm: add a "struct page_frag" type containing a page, offset and length
Date
A few network drivers currently use skb_frag_struct for this purpose but I have
patches which add additional fields and semantics there which these other uses
do not want.

A structure for reference sub-page regions seems like a generally useful thing
so do so instead of adding a network subsystem specific structure.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Jens Axboe <jaxboe@fusionio.com>
Cc: linux-mm@kvack.org
Cc: linux-kernel@vger.kernel.org
[since v1: s/struct subpage/struct page_frag/ on advice from Christoph]
---
include/linux/mm_types.h | 11 +++++++++++
1 files changed, 11 insertions(+), 0 deletions(-)

diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
index 774b895..575faaf 100644
--- a/include/linux/mm_types.h
+++ b/include/linux/mm_types.h
@@ -135,6 +135,17 @@ struct page {
#endif
;

+struct page_frag {
+ struct page *page;
+#if (BITS_PER_LONG > 32) || (PAGE_SIZE >= 65536)
+ __u32 page_offset;
+ __u32 size;
+#else
+ __u16 page_offset;
+ __u16 size;
+#endif
+};
+
typedef unsigned long __nocast vm_flags_t;

/*
--
1.7.2.5


\
 
 \ /
  Last update: 2011-10-13 12:05    [W:2.070 / U:0.972 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site