diff options
Diffstat (limited to 'freebsd/sys/sys/sglist.h')
| -rw-r--r-- | freebsd/sys/sys/sglist.h | 113 |
1 files changed, 113 insertions, 0 deletions
diff --git a/freebsd/sys/sys/sglist.h b/freebsd/sys/sys/sglist.h new file mode 100644 index 00000000..5674416c --- /dev/null +++ b/freebsd/sys/sys/sglist.h @@ -0,0 +1,113 @@ +/*- + * 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__ */ |