From 5a7b921046216e7a029dc818ff9f0b251a0aaf12 Mon Sep 17 00:00:00 2001 From: Tim Date: Mon, 24 Jan 2011 18:42:09 -0800 Subject: [PATCH] Pull in FreeBSD's sglist --- sys/conf/files | 1 + sys/kern/subr_sglist.c | 711 ++++++++++++++++++++++++++++++++++++++++++++++++ sys/sys/sglist.h | 104 +++++++ 3 files changed, 816 insertions(+), 0 deletions(-) create mode 100644 sys/kern/subr_sglist.c create mode 100644 sys/sys/sglist.h diff --git a/sys/conf/files b/sys/conf/files index 3707744..e62dcf0 100644 --- a/sys/conf/files +++ b/sys/conf/files @@ -978,6 +978,7 @@ kern/subr_alist.c standard kern/subr_blist.c standard kern/subr_sbuf.c standard kern/subr_scanf.c standard +kern/subr_sglist.c standard kern/subr_taskqueue.c standard kern/sys_generic.c standard kern/sys_pipe.c standard diff --git a/sys/kern/subr_sglist.c b/sys/kern/subr_sglist.c new file mode 100644 index 0000000..0d1bb80 --- /dev/null +++ b/sys/kern/subr_sglist.c @@ -0,0 +1,711 @@ +/*- + * Copyright (c) 2008 Yahoo!, Inc. + * All rights reserved. + * Written by: John Baldwin + * + * 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. + */ + +#include + +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include + +#include + +static MALLOC_DEFINE(M_SGLIST, "sglist", "scatter/gather lists"); + +/* + * Convenience macros to save the state of an sglist so it can be restored + * if an append attempt fails. Since sglist's only grow we only need to + * save the current count of segments and the length of the ending segment. + * Earlier segments will not be changed by an append, and the only change + * that can occur to the ending segment is that it can be extended. + */ +struct sgsave { + u_short sg_nseg; + size_t ss_len; +}; + +#define SGLIST_SAVE(sg, sgsave) do { \ + (sgsave).sg_nseg = (sg)->sg_nseg; \ + if ((sgsave).sg_nseg > 0) \ + (sgsave).ss_len = (sg)->sg_segs[(sgsave).sg_nseg - 1].ss_len; \ + else \ + (sgsave).ss_len = 0; \ +} while (0) + +#define SGLIST_RESTORE(sg, sgsave) do { \ + (sg)->sg_nseg = (sgsave).sg_nseg; \ + if ((sgsave).sg_nseg > 0) \ + (sg)->sg_segs[(sgsave).sg_nseg - 1].ss_len = (sgsave).ss_len; \ +} while (0) + +/* + * Append a single (paddr, len) to a sglist. sg is the list and ss is + * the current segment in the list. If we run out of segments then + * EFBIG will be returned. + */ +static __inline int +_sglist_append_range(struct sglist *sg, struct sglist_seg **ssp, + vm_paddr_t paddr, size_t len) +{ + struct sglist_seg *ss; + + ss = *ssp; + if (ss->ss_paddr + ss->ss_len == paddr) + ss->ss_len += len; + else { + if (sg->sg_nseg == sg->sg_maxseg) + return (EFBIG); + ss++; + ss->ss_paddr = paddr; + ss->ss_len = len; + sg->sg_nseg++; + *ssp = ss; + } + return (0); +} + +/* + * Worker routine to append a virtual address range (either kernel or + * user) to a scatter/gather list. + */ +static __inline int +_sglist_append_buf(struct sglist *sg, void *buf, size_t len, pmap_t pmap, + size_t *donep) +{ + struct sglist_seg *ss; + vm_offset_t vaddr, offset; + vm_paddr_t paddr; + size_t seglen; + int error; + + if (donep) + *donep = 0; + if (len == 0) + return (0); + + /* Do the first page. It may have an offset. */ + vaddr = (vm_offset_t)buf; + offset = vaddr & PAGE_MASK; + if (pmap != NULL) + paddr = pmap_extract(pmap, vaddr); + else + paddr = pmap_kextract(vaddr); + seglen = MIN(len, PAGE_SIZE - offset); + if (sg->sg_nseg == 0) { + ss = sg->sg_segs; + ss->ss_paddr = paddr; + ss->ss_len = seglen; + sg->sg_nseg = 1; + } else { + ss = &sg->sg_segs[sg->sg_nseg - 1]; + error = _sglist_append_range(sg, &ss, paddr, seglen); + if (error) + return (error); + } + vaddr += seglen; + len -= seglen; + if (donep) + *donep += seglen; + + while (len > 0) { + seglen = MIN(len, PAGE_SIZE); + if (pmap != NULL) + paddr = pmap_extract(pmap, vaddr); + else + paddr = pmap_kextract(vaddr); + error = _sglist_append_range(sg, &ss, paddr, seglen); + if (error) + return (error); + vaddr += seglen; + len -= seglen; + if (donep) + *donep += seglen; + } + + return (0); +} + +/* + * Determine the number of scatter/gather list elements needed to + * describe a kernel virtual address range. + */ +int +sglist_count(void *buf, size_t len) +{ + vm_offset_t vaddr, vendaddr; + vm_paddr_t lastaddr, paddr; + int nsegs; + + if (len == 0) + return (0); + + vaddr = trunc_page((vm_offset_t)buf); + vendaddr = (vm_offset_t)buf + len; + nsegs = 1; + lastaddr = pmap_kextract(vaddr); + vaddr += PAGE_SIZE; + while (vaddr < vendaddr) { + paddr = pmap_kextract(vaddr); + if (lastaddr + PAGE_SIZE != paddr) + nsegs++; + lastaddr = paddr; + vaddr += PAGE_SIZE; + } + return (nsegs); +} + +/* + * Allocate a scatter/gather list along with 'nsegs' segments. The + * 'mflags' parameters are the same as passed to malloc(9). The caller + * should use sglist_free() to free this list. + */ +struct sglist * +sglist_alloc(int nsegs, int mflags) +{ + struct sglist *sg; + + sg = kmalloc(sizeof(struct sglist) + nsegs * sizeof(struct sglist_seg), + M_SGLIST, mflags); + if (sg == NULL) + return (NULL); + sglist_init(sg, nsegs, (struct sglist_seg *)(sg + 1)); + return (sg); +} + +/* + * Free a scatter/gather list allocated via sglist_allc(). + */ +void +sglist_free(struct sglist *sg) +{ + + if (refcount_release(&sg->sg_refs)) + kfree(sg, M_SGLIST); +} + +/* + * Append the segments to describe a single kernel virtual address + * range to a scatter/gather list. If there are insufficient + * segments, then this fails with EFBIG. + */ +int +sglist_append(struct sglist *sg, void *buf, size_t len) +{ + struct sgsave save; + int error; + + if (sg->sg_maxseg == 0) + return (EINVAL); + SGLIST_SAVE(sg, save); + error = _sglist_append_buf(sg, buf, len, NULL, NULL); + if (error) + SGLIST_RESTORE(sg, save); + return (error); +} + +/* + * Append a single physical address range to a scatter/gather list. + * If there are insufficient segments, then this fails with EFBIG. + */ +int +sglist_append_phys(struct sglist *sg, vm_paddr_t paddr, size_t len) +{ + struct sglist_seg *ss; + struct sgsave save; + int error; + + if (sg->sg_maxseg == 0) + return (EINVAL); + if (len == 0) + return (0); + + if (sg->sg_nseg == 0) { + sg->sg_segs[0].ss_paddr = paddr; + sg->sg_segs[0].ss_len = len; + sg->sg_nseg = 1; + return (0); + } + ss = &sg->sg_segs[sg->sg_nseg - 1]; + SGLIST_SAVE(sg, save); + error = _sglist_append_range(sg, &ss, paddr, len); + if (error) + SGLIST_RESTORE(sg, save); + return (error); +} + +/* + * Append the segments that describe a single mbuf chain to a + * scatter/gather list. If there are insufficient segments, then this + * fails with EFBIG. + */ +int +sglist_append_mbuf(struct sglist *sg, struct mbuf *m0) +{ + struct sgsave save; + struct mbuf *m; + int error; + + if (sg->sg_maxseg == 0) + return (EINVAL); + + error = 0; + SGLIST_SAVE(sg, save); + for (m = m0; m != NULL; m = m->m_next) { + if (m->m_len > 0) { + error = sglist_append(sg, m->m_data, m->m_len); + if (error) { + SGLIST_RESTORE(sg, save); + return (error); + } + } + } + return (0); +} + +/* + * Append the segments that describe a single user address range to a + * scatter/gather list. If there are insufficient segments, then this + * fails with EFBIG. + */ +int +sglist_append_user(struct sglist *sg, void *buf, size_t len, struct thread *td) +{ + struct sgsave save; + int error; + + if (sg->sg_maxseg == 0) + return (EINVAL); + SGLIST_SAVE(sg, save); + error = _sglist_append_buf(sg, buf, len, + vmspace_pmap(td->td_proc->p_vmspace), NULL); + if (error) + SGLIST_RESTORE(sg, save); + return (error); +} + +/* + * Append the segments that describe a single uio to a scatter/gather + * list. If there are insufficient segments, then this fails with + * EFBIG. + */ +int +sglist_append_uio(struct sglist *sg, struct uio *uio) +{ + struct iovec *iov; + struct sgsave save; + size_t resid, minlen; + pmap_t pmap; + int error, i; + + if (sg->sg_maxseg == 0) + return (EINVAL); + + resid = uio->uio_resid; + iov = uio->uio_iov; + + if (uio->uio_segflg == UIO_USERSPACE) { + KASSERT(uio->uio_td != NULL, + ("sglist_append_uio: USERSPACE but no thread")); + pmap = vmspace_pmap(uio->uio_td->td_proc->p_vmspace); + } else + pmap = NULL; + + error = 0; + SGLIST_SAVE(sg, save); + for (i = 0; i < uio->uio_iovcnt && resid != 0; i++) { + /* + * Now at the first iovec to load. Load each iovec + * until we have exhausted the residual count. + */ + minlen = MIN(resid, iov[i].iov_len); + if (minlen > 0) { + error = _sglist_append_buf(sg, iov[i].iov_base, minlen, + pmap, NULL); + if (error) { + SGLIST_RESTORE(sg, save); + return (error); + } + resid -= minlen; + } + } + return (0); +} + +/* + * Append the segments that describe at most 'resid' bytes from a + * single uio to a scatter/gather list. If there are insufficient + * segments, then only the amount that fits is appended. + */ +int +sglist_consume_uio(struct sglist *sg, struct uio *uio, size_t resid) +{ + struct iovec *iov; + size_t done; + pmap_t pmap; + int error, len; + + if (sg->sg_maxseg == 0) + return (EINVAL); + + if (uio->uio_segflg == UIO_USERSPACE) { + KASSERT(uio->uio_td != NULL, + ("sglist_consume_uio: USERSPACE but no thread")); + pmap = vmspace_pmap(uio->uio_td->td_proc->p_vmspace); + } else + pmap = NULL; + + error = 0; + while (resid > 0 && uio->uio_resid) { + iov = uio->uio_iov; + len = iov->iov_len; + if (len == 0) { + uio->uio_iov++; + uio->uio_iovcnt--; + continue; + } + if (len > resid) + len = resid; + + /* + * Try to append this iovec. If we run out of room, + * then break out of the loop. + */ + error = _sglist_append_buf(sg, iov->iov_base, len, pmap, &done); + iov->iov_base = (char *)iov->iov_base + done; + iov->iov_len -= done; + uio->uio_resid -= done; + uio->uio_offset += done; + resid -= done; + if (error) + break; + } + return (0); +} + +/* + * Allocate and populate a scatter/gather list to describe a single + * kernel virtual address range. + */ +struct sglist * +sglist_build(void *buf, size_t len, int mflags) +{ + struct sglist *sg; + int nsegs; + + if (len == 0) + return (NULL); + + nsegs = sglist_count(buf, len); + sg = sglist_alloc(nsegs, mflags); + if (sg == NULL) + return (NULL); + if (sglist_append(sg, buf, len) != 0) { + sglist_free(sg); + return (NULL); + } + return (sg); +} + +/* + * Clone a new copy of a scatter/gather list. + */ +struct sglist * +sglist_clone(struct sglist *sg, int mflags) +{ + struct sglist *new; + + if (sg == NULL) + return (NULL); + new = sglist_alloc(sg->sg_maxseg, mflags); + if (new == NULL) + return (NULL); + new->sg_nseg = sg->sg_nseg; + bcopy(sg->sg_segs, new->sg_segs, sizeof(struct sglist_seg) * + sg->sg_nseg); + return (new); +} + +/* + * Calculate the total length of the segments described in a + * scatter/gather list. + */ +size_t +sglist_length(struct sglist *sg) +{ + size_t space; + int i; + + space = 0; + for (i = 0; i < sg->sg_nseg; i++) + space += sg->sg_segs[i].ss_len; + return (space); +} + +/* + * Split a scatter/gather list into two lists. The scatter/gather + * entries for the first 'length' bytes of the 'original' list are + * stored in the '*head' list and are removed from 'original'. + * + * If '*head' is NULL, then a new list will be allocated using + * 'mflags'. If M_NOWAIT is specified and the allocation fails, + * ENOMEM will be returned. + * + * If '*head' is not NULL, it should point to an empty sglist. If it + * does not have enough room for the remaining space, then EFBIG will + * be returned. If '*head' is not empty, then EINVAL will be + * returned. + * + * If 'original' is shared (refcount > 1), then EDOOFUS will be + * returned. + */ +int +sglist_split(struct sglist *original, struct sglist **head, size_t length, + int mflags) +{ + struct sglist *sg; + size_t space, split; + int count, i; + + if (original->sg_refs > 1) + return (EDOOFUS); + + /* Figure out how big of a sglist '*head' has to hold. */ + count = 0; + space = 0; + split = 0; + for (i = 0; i < original->sg_nseg; i++) { + space += original->sg_segs[i].ss_len; + count++; + if (space >= length) { + /* + * If 'length' falls in the middle of a + * scatter/gather list entry, then 'split' + * holds how much of that entry will remain in + * 'original'. + */ + split = space - length; + break; + } + } + + /* Nothing to do, so leave head empty. */ + if (count == 0) + return (0); + + if (*head == NULL) { + sg = sglist_alloc(count, mflags); + if (sg == NULL) + return (ENOMEM); + *head = sg; + } else { + sg = *head; + if (sg->sg_maxseg < count) + return (EFBIG); + if (sg->sg_nseg != 0) + return (EINVAL); + } + + /* Copy 'count' entries to 'sg' from 'original'. */ + bcopy(original->sg_segs, sg->sg_segs, count * + sizeof(struct sglist_seg)); + sg->sg_nseg = count; + + /* + * If we had to split a list entry, fixup the last entry in + * 'sg' and the new first entry in 'original'. We also + * decrement 'count' by 1 since we will only be removing + * 'count - 1' segments from 'original' now. + */ + if (split != 0) { + count--; + sg->sg_segs[count].ss_len -= split; + original->sg_segs[count].ss_paddr = + sg->sg_segs[count].ss_paddr + split; + original->sg_segs[count].ss_len = split; + } + + /* Trim 'count' entries from the front of 'original'. */ + original->sg_nseg -= count; + bcopy(original->sg_segs + count, original->sg_segs, count * + sizeof(struct sglist_seg)); + return (0); +} + +/* + * Append the scatter/gather list elements in 'second' to the + * scatter/gather list 'first'. If there is not enough space in + * 'first', EFBIG is returned. + */ +int +sglist_join(struct sglist *first, struct sglist *second) +{ + struct sglist_seg *flast, *sfirst; + int append; + + /* If 'second' is empty, there is nothing to do. */ + if (second->sg_nseg == 0) + return (0); + + /* + * If the first entry in 'second' can be appended to the last entry + * in 'first' then set append to '1'. + */ + append = 0; + flast = &first->sg_segs[first->sg_nseg - 1]; + sfirst = &second->sg_segs[0]; + if (first->sg_nseg != 0 && + flast->ss_paddr + flast->ss_len == sfirst->ss_paddr) + append = 1; + + /* Make sure 'first' has enough room. */ + if (first->sg_nseg + second->sg_nseg - append > first->sg_maxseg) + return (EFBIG); + + /* Merge last in 'first' and first in 'second' if needed. */ + if (append) + flast->ss_len += sfirst->ss_len; + + /* Append new segments from 'second' to 'first'. */ + bcopy(first->sg_segs + first->sg_nseg, second->sg_segs + append, + (second->sg_nseg - append) * sizeof(struct sglist_seg)); + first->sg_nseg += second->sg_nseg - append; + sglist_reset(second); + return (0); +} + +/* + * Generate a new scatter/gather list from a range of an existing + * scatter/gather list. The 'offset' and 'length' parameters specify + * the logical range of the 'original' list to extract. If that range + * is not a subset of the length of 'original', then EINVAL is + * returned. The new scatter/gather list is stored in '*slice'. + * + * If '*slice' is NULL, then a new list will be allocated using + * 'mflags'. If M_NOWAIT is specified and the allocation fails, + * ENOMEM will be returned. + * + * If '*slice' is not NULL, it should point to an empty sglist. If it + * does not have enough room for the remaining space, then EFBIG will + * be returned. If '*slice' is not empty, then EINVAL will be + * returned. + */ +int +sglist_slice(struct sglist *original, struct sglist **slice, size_t offset, + size_t length, int mflags) +{ + struct sglist *sg; + size_t space, end, foffs, loffs; + int count, i, fseg; + + /* Nothing to do. */ + if (length == 0) + return (0); + + /* Figure out how many segments '*slice' needs to have. */ + end = offset + length; + space = 0; + count = 0; + fseg = 0; + foffs = loffs = 0; + for (i = 0; i < original->sg_nseg; i++) { + space += original->sg_segs[i].ss_len; + if (space > offset) { + /* + * When we hit the first segment, store its index + * in 'fseg' and the offset into the first segment + * of 'offset' in 'foffs'. + */ + if (count == 0) { + fseg = i; + foffs = offset - (space - + original->sg_segs[i].ss_len); + //CTR1(KTR_DEV, "sglist_slice: foffs = %08lx", foffs); + } + count++; + + /* + * When we hit the last segment, break out of + * the loop. Store the amount of extra space + * at the end of this segment in 'loffs'. + */ + if (space >= end) { + loffs = space - end; + //CTR1(KTR_DEV, "sglist_slice: loffs = %08lx", loffs); + break; + } + } + } + + /* If we never hit 'end', then 'length' ran off the end, so fail. */ + if (space < end) + return (EINVAL); + + if (*slice == NULL) { + sg = sglist_alloc(count, mflags); + if (sg == NULL) + return (ENOMEM); + *slice = sg; + } else { + sg = *slice; + if (sg->sg_maxseg < count) + return (EFBIG); + if (sg->sg_nseg != 0) + return (EINVAL); + } + + /* + * Copy over 'count' segments from 'original' starting at + * 'fseg' to 'sg'. + */ + bcopy(original->sg_segs + fseg, sg->sg_segs, + count * sizeof(struct sglist_seg)); + sg->sg_nseg = count; + + /* Fixup first and last segments if needed. */ + if (foffs != 0) { + sg->sg_segs[0].ss_paddr += foffs; + sg->sg_segs[0].ss_len -= foffs; + //CTR2(KTR_DEV, "sglist_slice seg[0]: %08lx:%08lx", + // (long)sg->sg_segs[0].ss_paddr, sg->sg_segs[0].ss_len); + } + if (loffs != 0) { + sg->sg_segs[count - 1].ss_len -= loffs; + //CTR2(KTR_DEV, "sglist_slice seg[%d]: len %08x", count - 1, + // sg->sg_segs[count - 1].ss_len); + } + return (0); +} diff --git a/sys/sys/sglist.h b/sys/sys/sglist.h new file mode 100644 index 0000000..95d6dfa --- /dev/null +++ b/sys/sys/sglist.h @@ -0,0 +1,104 @@ +/*- + * Copyright (c) 2008 Yahoo!, Inc. + * All rights reserved. + * Written by: John Baldwin + * + * 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: src/sys/sys/sglist.h,v 1.1.2.2.4.1 2010/06/14 02:09:06 kensmith Exp $ + */ + +/* + * 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 + +struct sglist_seg { + vm_paddr_t ss_paddr; + size_t ss_len; +}; + +struct sglist { + struct sglist_seg *sg_segs; + int sg_refs; + u_short sg_nseg; + u_short sg_maxseg; +}; + +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_mbuf(struct sglist *sg, struct mbuf *m0); +int sglist_append_phys(struct sglist *sg, vm_paddr_t paddr, + size_t len); +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); +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); +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__ */ -- 1.7.0.4