578 lines
16 KiB
C
578 lines
16 KiB
C
/* $NetBSD: lfs_subr.c,v 1.45 2003/10/14 14:02:56 dbj Exp $ */
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/*-
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* Copyright (c) 1999, 2000, 2001, 2002, 2003 The NetBSD Foundation, Inc.
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* All rights reserved.
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*
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* This code is derived from software contributed to The NetBSD Foundation
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* by Konrad E. Schroder <perseant@hhhh.org>.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. All advertising materials mentioning features or use of this software
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* must display the following acknowledgement:
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* This product includes software developed by the NetBSD
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* Foundation, Inc. and its contributors.
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* 4. Neither the name of The NetBSD Foundation nor the names of its
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* contributors may be used to endorse or promote products derived
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* from this software without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
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* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
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* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
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* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
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* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
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* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
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* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
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* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
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* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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* POSSIBILITY OF SUCH DAMAGE.
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*/
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/*
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* Copyright (c) 1991, 1993
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* The Regents of the University of California. All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. Neither the name of the University nor the names of its contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*
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* @(#)lfs_subr.c 8.4 (Berkeley) 5/8/95
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*/
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#include <sys/cdefs.h>
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__KERNEL_RCSID(0, "$NetBSD: lfs_subr.c,v 1.45 2003/10/14 14:02:56 dbj Exp $");
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#include <sys/param.h>
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#include <sys/systm.h>
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#include <sys/namei.h>
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#include <sys/vnode.h>
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#include <sys/buf.h>
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#include <sys/mount.h>
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#include <sys/malloc.h>
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#include <sys/proc.h>
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#include <ufs/ufs/inode.h>
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#include <ufs/lfs/lfs.h>
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#include <ufs/lfs/lfs_extern.h>
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#include <uvm/uvm.h>
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/*
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* Return buffer with the contents of block "offset" from the beginning of
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* directory "ip". If "res" is non-zero, fill it in with a pointer to the
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* remaining space in the directory.
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*/
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int
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lfs_blkatoff(void *v)
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{
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struct vop_blkatoff_args /* {
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struct vnode *a_vp;
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off_t a_offset;
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char **a_res;
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struct buf **a_bpp;
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} */ *ap = v;
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struct lfs *fs;
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struct inode *ip;
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struct buf *bp;
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daddr_t lbn;
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int bsize, error;
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ip = VTOI(ap->a_vp);
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fs = ip->i_lfs;
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lbn = lblkno(fs, ap->a_offset);
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bsize = blksize(fs, ip, lbn);
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*ap->a_bpp = NULL;
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if ((error = bread(ap->a_vp, lbn, bsize, NOCRED, &bp)) != 0) {
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brelse(bp);
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return (error);
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}
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if (ap->a_res)
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*ap->a_res = (char *)bp->b_data + blkoff(fs, ap->a_offset);
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*ap->a_bpp = bp;
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return (0);
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}
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#ifdef LFS_DEBUG_MALLOC
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char *lfs_res_names[LFS_NB_COUNT] = {
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"summary",
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"superblock",
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"ifile block",
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"cluster",
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"clean",
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};
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#endif
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int lfs_res_qty[LFS_NB_COUNT] = {
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LFS_N_SUMMARIES,
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LFS_N_SBLOCKS,
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LFS_N_IBLOCKS,
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LFS_N_CLUSTERS,
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LFS_N_CLEAN,
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};
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void
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lfs_setup_resblks(struct lfs *fs)
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{
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int i, j;
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int maxbpp;
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fs->lfs_resblk = (res_t *)malloc(LFS_N_TOTAL * sizeof(res_t), M_SEGMENT,
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M_WAITOK);
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for (i = 0; i < LFS_N_TOTAL; i++) {
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fs->lfs_resblk[i].inuse = 0;
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fs->lfs_resblk[i].p = NULL;
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}
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for (i = 0; i < LFS_RESHASH_WIDTH; i++)
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LIST_INIT(fs->lfs_reshash + i);
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/*
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* These types of allocations can be larger than a page,
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* so we can't use the pool subsystem for them.
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*/
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for (i = 0, j = 0; j < LFS_N_SUMMARIES; j++, i++)
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fs->lfs_resblk[i].size = fs->lfs_sumsize;
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for (j = 0; j < LFS_N_SBLOCKS; j++, i++)
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fs->lfs_resblk[i].size = LFS_SBPAD;
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for (j = 0; j < LFS_N_IBLOCKS; j++, i++)
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fs->lfs_resblk[i].size = fs->lfs_bsize;
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for (j = 0; j < LFS_N_CLUSTERS; j++, i++)
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fs->lfs_resblk[i].size = MAXPHYS;
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for (j = 0; j < LFS_N_CLEAN; j++, i++)
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fs->lfs_resblk[i].size = MAXPHYS;
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for (i = 0; i < LFS_N_TOTAL; i++) {
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fs->lfs_resblk[i].p = malloc(fs->lfs_resblk[i].size,
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M_SEGMENT, M_WAITOK);
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}
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/*
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* Initialize pools for small types (XXX is BPP small?)
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*/
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pool_init(&fs->lfs_clpool, sizeof(struct lfs_cluster), 0, 0,
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LFS_N_CL, "lfsclpl", &pool_allocator_nointr);
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pool_init(&fs->lfs_segpool, sizeof(struct segment), 0, 0,
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LFS_N_SEG, "lfssegpool", &pool_allocator_nointr);
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maxbpp = ((fs->lfs_sumsize - SEGSUM_SIZE(fs)) / sizeof(int32_t) + 2);
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maxbpp = MIN(maxbpp, fs->lfs_ssize / fs->lfs_fsize + 2);
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pool_init(&fs->lfs_bpppool, maxbpp * sizeof(struct buf *), 0, 0,
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LFS_N_BPP, "lfsbpppl", &pool_allocator_nointr);
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}
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void
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lfs_free_resblks(struct lfs *fs)
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{
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int i;
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pool_destroy(&fs->lfs_bpppool);
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pool_destroy(&fs->lfs_segpool);
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pool_destroy(&fs->lfs_clpool);
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for (i = 0; i < LFS_N_TOTAL; i++) {
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while (fs->lfs_resblk[i].inuse)
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tsleep(&fs->lfs_resblk, PRIBIO + 1, "lfs_free", 0);
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if (fs->lfs_resblk[i].p != NULL)
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free(fs->lfs_resblk[i].p, M_SEGMENT);
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}
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free(fs->lfs_resblk, M_SEGMENT);
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}
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static unsigned int
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lfs_mhash(void *vp)
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{
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return (unsigned int)(((unsigned long)vp) >> 2) % LFS_RESHASH_WIDTH;
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}
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/*
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* Return memory of the given size for the given purpose, or use one of a
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* number of spare last-resort buffers, if malloc returns NULL.
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*/
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void *
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lfs_malloc(struct lfs *fs, size_t size, int type)
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{
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struct lfs_res_blk *re;
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void *r;
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int i, s, start;
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unsigned int h;
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r = NULL;
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/* If no mem allocated for this type, it just waits */
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if (lfs_res_qty[type] == 0) {
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r = malloc(size, M_SEGMENT, M_WAITOK);
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return r;
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}
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/* Otherwise try a quick malloc, and if it works, great */
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if ((r = malloc(size, M_SEGMENT, M_NOWAIT)) != NULL) {
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return r;
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}
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/*
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* If malloc returned NULL, we are forced to use one of our
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* reserve blocks. We have on hand at least one summary block,
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* at least one cluster block, at least one superblock,
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* and several indirect blocks.
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*/
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/* skip over blocks of other types */
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for (i = 0, start = 0; i < type; i++)
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start += lfs_res_qty[i];
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while (r == NULL) {
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for (i = 0; i < lfs_res_qty[type]; i++) {
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if (fs->lfs_resblk[start + i].inuse == 0) {
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re = fs->lfs_resblk + start + i;
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re->inuse = 1;
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r = re->p;
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KASSERT(re->size >= size);
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h = lfs_mhash(r);
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s = splbio();
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LIST_INSERT_HEAD(&fs->lfs_reshash[h], re, res);
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splx(s);
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return r;
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}
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}
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#ifdef LFS_DEBUG_MALLOC
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printf("sleeping on %s (%d)\n", lfs_res_names[type], lfs_res_qty[type]);
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#endif
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tsleep(&fs->lfs_resblk, PVM, "lfs_malloc", 0);
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#ifdef LFS_DEBUG_MALLOC
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printf("done sleeping on %s\n", lfs_res_names[type]);
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#endif
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}
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/* NOTREACHED */
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return r;
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}
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void
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lfs_free(struct lfs *fs, void *p, int type)
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{
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int s;
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unsigned int h;
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res_t *re;
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#ifdef DEBUG
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int i;
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#endif
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h = lfs_mhash(p);
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s = splbio();
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LIST_FOREACH(re, &fs->lfs_reshash[h], res) {
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if (re->p == p) {
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KASSERT(re->inuse == 1);
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LIST_REMOVE(re, res);
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re->inuse = 0;
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wakeup(&fs->lfs_resblk);
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splx(s);
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return;
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}
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}
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#ifdef DEBUG
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for (i = 0; i < LFS_N_TOTAL; i++) {
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if (fs->lfs_resblk[i].p == p)
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panic("lfs_free: inconsistent reserved block");
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}
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#endif
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splx(s);
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/*
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* If we didn't find it, free it.
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*/
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free(p, M_SEGMENT);
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}
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/*
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* lfs_seglock --
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* Single thread the segment writer.
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*/
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int
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lfs_seglock(struct lfs *fs, unsigned long flags)
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{
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struct segment *sp;
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simple_lock(&fs->lfs_interlock);
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if (fs->lfs_seglock) {
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if (fs->lfs_lockpid == curproc->p_pid) {
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simple_unlock(&fs->lfs_interlock);
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++fs->lfs_seglock;
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fs->lfs_sp->seg_flags |= flags;
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return 0;
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} else if (flags & SEGM_PAGEDAEMON) {
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simple_unlock(&fs->lfs_interlock);
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return EWOULDBLOCK;
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} else while (fs->lfs_seglock)
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(void)ltsleep(&fs->lfs_seglock, PRIBIO + 1,
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"lfs seglock", 0, &fs->lfs_interlock);
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}
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fs->lfs_seglock = 1;
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fs->lfs_lockpid = curproc->p_pid;
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simple_unlock(&fs->lfs_interlock);
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fs->lfs_cleanind = 0;
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/* Drain fragment size changes out */
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lockmgr(&fs->lfs_fraglock, LK_EXCLUSIVE, 0);
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sp = fs->lfs_sp = pool_get(&fs->lfs_segpool, PR_WAITOK);
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sp->bpp = pool_get(&fs->lfs_bpppool, PR_WAITOK);
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sp->seg_flags = flags;
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sp->vp = NULL;
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sp->seg_iocount = 0;
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(void) lfs_initseg(fs);
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/*
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* Keep a cumulative count of the outstanding I/O operations. If the
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* disk drive catches up with us it could go to zero before we finish,
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* so we artificially increment it by one until we've scheduled all of
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* the writes we intend to do.
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*/
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++fs->lfs_iocount;
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return 0;
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}
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static void lfs_unmark_dirop(struct lfs *);
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static void
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lfs_unmark_dirop(struct lfs *fs)
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{
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struct inode *ip, *nip;
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struct vnode *vp;
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int doit;
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simple_lock(&fs->lfs_interlock);
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doit = !(fs->lfs_flags & LFS_UNDIROP);
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if (doit)
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fs->lfs_flags |= LFS_UNDIROP;
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simple_unlock(&fs->lfs_interlock);
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if (!doit)
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return;
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for (ip = TAILQ_FIRST(&fs->lfs_dchainhd); ip != NULL; ip = nip) {
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nip = TAILQ_NEXT(ip, i_lfs_dchain);
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vp = ITOV(ip);
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if (VOP_ISLOCKED(vp) &&
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vp->v_lock.lk_lockholder != curproc->p_pid) {
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continue;
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}
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if ((VTOI(vp)->i_flag & IN_ADIROP) == 0) {
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--lfs_dirvcount;
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vp->v_flag &= ~VDIROP;
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TAILQ_REMOVE(&fs->lfs_dchainhd, ip, i_lfs_dchain);
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wakeup(&lfs_dirvcount);
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fs->lfs_unlockvp = vp;
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vrele(vp);
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fs->lfs_unlockvp = NULL;
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}
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}
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simple_lock(&fs->lfs_interlock);
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fs->lfs_flags &= ~LFS_UNDIROP;
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simple_unlock(&fs->lfs_interlock);
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}
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static void
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lfs_auto_segclean(struct lfs *fs)
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{
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int i, error;
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/*
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* Now that we've swapped lfs_activesb, but while we still
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* hold the segment lock, run through the segment list marking
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* the empty ones clean.
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* XXX - do we really need to do them all at once?
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*/
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for (i = 0; i < fs->lfs_nseg; i++) {
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if ((fs->lfs_suflags[0][i] &
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(SEGUSE_ACTIVE | SEGUSE_DIRTY | SEGUSE_EMPTY)) ==
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(SEGUSE_DIRTY | SEGUSE_EMPTY) &&
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(fs->lfs_suflags[1][i] &
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(SEGUSE_ACTIVE | SEGUSE_DIRTY | SEGUSE_EMPTY)) ==
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(SEGUSE_DIRTY | SEGUSE_EMPTY)) {
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if ((error = lfs_do_segclean(fs, i)) != 0) {
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#ifdef DEBUG
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printf("lfs_auto_segclean: lfs_do_segclean returned %d for seg %d\n", error, i);
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#endif /* DEBUG */
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}
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}
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fs->lfs_suflags[1 - fs->lfs_activesb][i] =
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fs->lfs_suflags[fs->lfs_activesb][i];
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}
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}
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/*
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* lfs_segunlock --
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* Single thread the segment writer.
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*/
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void
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lfs_segunlock(struct lfs *fs)
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{
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struct segment *sp;
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unsigned long sync, ckp;
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struct buf *bp;
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int do_unmark_dirop = 0;
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sp = fs->lfs_sp;
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simple_lock(&fs->lfs_interlock);
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if (fs->lfs_seglock == 1) {
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if ((sp->seg_flags & SEGM_PROT) == 0)
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do_unmark_dirop = 1;
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simple_unlock(&fs->lfs_interlock);
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sync = sp->seg_flags & SEGM_SYNC;
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ckp = sp->seg_flags & SEGM_CKP;
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if (sp->bpp != sp->cbpp) {
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/* Free allocated segment summary */
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fs->lfs_offset -= btofsb(fs, fs->lfs_sumsize);
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bp = *sp->bpp;
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lfs_freebuf(fs, bp);
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} else
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printf ("unlock to 0 with no summary");
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pool_put(&fs->lfs_bpppool, sp->bpp);
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sp->bpp = NULL;
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/*
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* If we're not sync, we're done with sp, get rid of it.
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* Otherwise, we keep a local copy around but free
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* fs->lfs_sp so another process can use it (we have to
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* wait but they don't have to wait for us).
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*/
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if (!sync)
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pool_put(&fs->lfs_segpool, sp);
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fs->lfs_sp = NULL;
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/*
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* If the I/O count is non-zero, sleep until it reaches zero.
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* At the moment, the user's process hangs around so we can
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* sleep.
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*/
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if (--fs->lfs_iocount == 0)
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LFS_DEBUG_COUNTLOCKED("lfs_segunlock");
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if (fs->lfs_iocount <= 1)
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|
wakeup(&fs->lfs_iocount);
|
|
/*
|
|
* If we're not checkpointing, we don't have to block
|
|
* other processes to wait for a synchronous write
|
|
* to complete.
|
|
*/
|
|
if (!ckp) {
|
|
simple_lock(&fs->lfs_interlock);
|
|
--fs->lfs_seglock;
|
|
fs->lfs_lockpid = 0;
|
|
simple_unlock(&fs->lfs_interlock);
|
|
wakeup(&fs->lfs_seglock);
|
|
}
|
|
/*
|
|
* We let checkpoints happen asynchronously. That means
|
|
* that during recovery, we have to roll forward between
|
|
* the two segments described by the first and second
|
|
* superblocks to make sure that the checkpoint described
|
|
* by a superblock completed.
|
|
*/
|
|
while (ckp && sync && fs->lfs_iocount)
|
|
(void)tsleep(&fs->lfs_iocount, PRIBIO + 1,
|
|
"lfs_iocount", 0);
|
|
while (sync && sp->seg_iocount) {
|
|
(void)tsleep(&sp->seg_iocount, PRIBIO + 1,
|
|
"seg_iocount", 0);
|
|
/* printf("sleeping on iocount %x == %d\n", sp, sp->seg_iocount); */
|
|
}
|
|
if (sync)
|
|
pool_put(&fs->lfs_segpool, sp);
|
|
|
|
if (ckp) {
|
|
fs->lfs_nactive = 0;
|
|
/* If we *know* everything's on disk, write both sbs */
|
|
/* XXX should wait for this one */
|
|
if (sync)
|
|
lfs_writesuper(fs, fs->lfs_sboffs[fs->lfs_activesb]);
|
|
lfs_writesuper(fs, fs->lfs_sboffs[1 - fs->lfs_activesb]);
|
|
if (!(fs->lfs_ivnode->v_mount->mnt_iflag & IMNT_UNMOUNT))
|
|
lfs_auto_segclean(fs);
|
|
fs->lfs_activesb = 1 - fs->lfs_activesb;
|
|
simple_lock(&fs->lfs_interlock);
|
|
--fs->lfs_seglock;
|
|
fs->lfs_lockpid = 0;
|
|
simple_unlock(&fs->lfs_interlock);
|
|
wakeup(&fs->lfs_seglock);
|
|
}
|
|
/* Reenable fragment size changes */
|
|
lockmgr(&fs->lfs_fraglock, LK_RELEASE, 0);
|
|
if (do_unmark_dirop)
|
|
lfs_unmark_dirop(fs);
|
|
} else if (fs->lfs_seglock == 0) {
|
|
simple_unlock(&fs->lfs_interlock);
|
|
panic ("Seglock not held");
|
|
} else {
|
|
--fs->lfs_seglock;
|
|
simple_unlock(&fs->lfs_interlock);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* drain dirops and start writer.
|
|
*/
|
|
int
|
|
lfs_writer_enter(struct lfs *fs, const char *wmesg)
|
|
{
|
|
int error = 0;
|
|
|
|
simple_lock(&fs->lfs_interlock);
|
|
|
|
/* disallow dirops during flush */
|
|
fs->lfs_writer++;
|
|
|
|
while (fs->lfs_dirops > 0) {
|
|
++fs->lfs_diropwait;
|
|
error = ltsleep(&fs->lfs_writer, PRIBIO+1, wmesg, 0,
|
|
&fs->lfs_interlock);
|
|
--fs->lfs_diropwait;
|
|
}
|
|
|
|
if (error)
|
|
fs->lfs_writer--;
|
|
|
|
simple_unlock(&fs->lfs_interlock);
|
|
|
|
return error;
|
|
}
|
|
|
|
void
|
|
lfs_writer_leave(struct lfs *fs)
|
|
{
|
|
boolean_t dowakeup;
|
|
|
|
simple_lock(&fs->lfs_interlock);
|
|
dowakeup = !(--fs->lfs_writer);
|
|
simple_unlock(&fs->lfs_interlock);
|
|
if (dowakeup)
|
|
wakeup(&fs->lfs_dirops);
|
|
}
|