freebsd-skq/sys/sys/sglist.h
pfg 4736ccfd9c sys: further adoption of SPDX licensing ID tags.
Mainly focus on files that use BSD 3-Clause license.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

Special thanks to Wind River for providing access to "The Duke of
Highlander" tool: an older (2014) run over FreeBSD tree was useful as a
starting point.
2017-11-20 19:43:44 +00:00

114 lines
3.7 KiB
C

/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (c) 2008 Yahoo!, Inc.
* All rights reserved.
* Written by: John Baldwin <jhb@FreeBSD.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the author nor the names of any co-contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
/*
* A scatter/gather list describes a group of physical address ranges.
* Each physical address range consists of a starting address and a
* length.
*/
#ifndef __SGLIST_H__
#define __SGLIST_H__
#include <sys/refcount.h>
struct sglist_seg {
vm_paddr_t ss_paddr;
size_t ss_len;
};
struct sglist {
struct sglist_seg *sg_segs;
u_int sg_refs;
u_short sg_nseg;
u_short sg_maxseg;
};
struct bio;
struct mbuf;
struct uio;
static __inline void
sglist_init(struct sglist *sg, u_short maxsegs, struct sglist_seg *segs)
{
sg->sg_segs = segs;
sg->sg_nseg = 0;
sg->sg_maxseg = maxsegs;
refcount_init(&sg->sg_refs, 1);
}
static __inline void
sglist_reset(struct sglist *sg)
{
sg->sg_nseg = 0;
}
static __inline struct sglist *
sglist_hold(struct sglist *sg)
{
refcount_acquire(&sg->sg_refs);
return (sg);
}
struct sglist *sglist_alloc(int nsegs, int mflags);
int sglist_append(struct sglist *sg, void *buf, size_t len);
int sglist_append_bio(struct sglist *sg, struct bio *bp);
int sglist_append_mbuf(struct sglist *sg, struct mbuf *m0);
int sglist_append_phys(struct sglist *sg, vm_paddr_t paddr,
size_t len);
int sglist_append_sglist(struct sglist *sg, struct sglist *source,
size_t offset, size_t length);
int sglist_append_uio(struct sglist *sg, struct uio *uio);
int sglist_append_user(struct sglist *sg, void *buf, size_t len,
struct thread *td);
int sglist_append_vmpages(struct sglist *sg, vm_page_t *m, size_t pgoff,
size_t len);
struct sglist *sglist_build(void *buf, size_t len, int mflags);
struct sglist *sglist_clone(struct sglist *sg, int mflags);
int sglist_consume_uio(struct sglist *sg, struct uio *uio, size_t resid);
int sglist_count(void *buf, size_t len);
int sglist_count_vmpages(vm_page_t *m, size_t pgoff, size_t len);
void sglist_free(struct sglist *sg);
int sglist_join(struct sglist *first, struct sglist *second);
size_t sglist_length(struct sglist *sg);
int sglist_slice(struct sglist *original, struct sglist **slice,
size_t offset, size_t length, int mflags);
int sglist_split(struct sglist *original, struct sglist **head,
size_t length, int mflags);
#endif /* !__SGLIST_H__ */