Commit d32311fe authored by Herbert Xu's avatar Herbert Xu
Browse files

[PATCH] Introduce sg_set_buf 



sg_init_one is a nice tool for the block layer.  However, users
of struct scatterlist in other subsystems don't usually need the
DMA attributes.  For them it's a waste of time and space to
initialise the whole struct scatterlist structure.

Therefore this patch adds a new function sg_set_buf to initialise
a scatterlist without zeroing the DMA attributes.

Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
parent be15cd72

include/linux/scatterlist.h

+13 −4
Original line number Diff line number Diff line 
#ifndef _LINUX_SCATTERLIST_H

#define _LINUX_SCATTERLIST_H



static inline void sg_init_one(struct scatterlist *sg,

			       u8 *buf, unsigned int buflen)

{

	memset(sg, 0, sizeof(*sg));

#include <asm/scatterlist.h>

#include <linux/mm.h>

#include <linux/string.h>



static inline void sg_set_buf(struct scatterlist *sg, void *buf,

			      unsigned int buflen)

{

	sg->page = virt_to_page(buf);

	sg->offset = offset_in_page(buf);

	sg->length = buflen;

}



static inline void sg_init_one(struct scatterlist *sg, void *buf,

			       unsigned int buflen)

{

	memset(sg, 0, sizeof(*sg));

	sg_set_buf(sg, buf, buflen);

}



#endif /* _LINUX_SCATTERLIST_H */

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