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lfs_alloc.c revision 1.94
      1 /*	$NetBSD: lfs_alloc.c,v 1.94 2006/05/14 21:32:45 elad Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 1999, 2000, 2001, 2002, 2003 The NetBSD Foundation, Inc.
      5  * All rights reserved.
      6  *
      7  * This code is derived from software contributed to The NetBSD Foundation
      8  * by Konrad E. Schroder <perseant (at) hhhh.org>.
      9  *
     10  * Redistribution and use in source and binary forms, with or without
     11  * modification, are permitted provided that the following conditions
     12  * are met:
     13  * 1. Redistributions of source code must retain the above copyright
     14  *    notice, this list of conditions and the following disclaimer.
     15  * 2. Redistributions in binary form must reproduce the above copyright
     16  *    notice, this list of conditions and the following disclaimer in the
     17  *    documentation and/or other materials provided with the distribution.
     18  * 3. All advertising materials mentioning features or use of this software
     19  *    must display the following acknowledgement:
     20  *	This product includes software developed by the NetBSD
     21  *	Foundation, Inc. and its contributors.
     22  * 4. Neither the name of The NetBSD Foundation nor the names of its
     23  *    contributors may be used to endorse or promote products derived
     24  *    from this software without specific prior written permission.
     25  *
     26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     36  * POSSIBILITY OF SUCH DAMAGE.
     37  */
     38 /*
     39  * Copyright (c) 1991, 1993
     40  *	The Regents of the University of California.  All rights reserved.
     41  *
     42  * Redistribution and use in source and binary forms, with or without
     43  * modification, are permitted provided that the following conditions
     44  * are met:
     45  * 1. Redistributions of source code must retain the above copyright
     46  *    notice, this list of conditions and the following disclaimer.
     47  * 2. Redistributions in binary form must reproduce the above copyright
     48  *    notice, this list of conditions and the following disclaimer in the
     49  *    documentation and/or other materials provided with the distribution.
     50  * 3. Neither the name of the University nor the names of its contributors
     51  *    may be used to endorse or promote products derived from this software
     52  *    without specific prior written permission.
     53  *
     54  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     55  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     56  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     57  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     58  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     59  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     60  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     61  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     62  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     63  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     64  * SUCH DAMAGE.
     65  *
     66  *	@(#)lfs_alloc.c	8.4 (Berkeley) 1/4/94
     67  */
     68 
     69 #include <sys/cdefs.h>
     70 __KERNEL_RCSID(0, "$NetBSD: lfs_alloc.c,v 1.94 2006/05/14 21:32:45 elad Exp $");
     71 
     72 #if defined(_KERNEL_OPT)
     73 #include "opt_quota.h"
     74 #endif
     75 
     76 #include <sys/param.h>
     77 #include <sys/systm.h>
     78 #include <sys/kernel.h>
     79 #include <sys/buf.h>
     80 #include <sys/lock.h>
     81 #include <sys/vnode.h>
     82 #include <sys/syslog.h>
     83 #include <sys/mount.h>
     84 #include <sys/malloc.h>
     85 #include <sys/pool.h>
     86 #include <sys/proc.h>
     87 #include <sys/tree.h>
     88 #include <sys/kauth.h>
     89 
     90 #include <ufs/ufs/quota.h>
     91 #include <ufs/ufs/inode.h>
     92 #include <ufs/ufs/ufsmount.h>
     93 #include <ufs/ufs/ufs_extern.h>
     94 
     95 #include <ufs/lfs/lfs.h>
     96 #include <ufs/lfs/lfs_extern.h>
     97 
     98 extern struct lock ufs_hashlock;
     99 
    100 static int extend_ifile(struct lfs *, kauth_cred_t);
    101 static int lfs_ialloc(struct lfs *, struct vnode *, ino_t, int,
    102     struct vnode **);
    103 
    104 /* Constants for inode free bitmap */
    105 #define BMSHIFT 5	/* 2 ** 5 = 32 */
    106 #define BMMASK  ((1 << BMSHIFT) - 1)
    107 #define SET_BITMAP_FREE(F, I) do { \
    108 	DLOG((DLOG_ALLOC, "lfs: ino %d wrd %d bit %d set\n", (int)(I), 	\
    109 	     (int)((I) >> BMSHIFT), (int)((I) & BMMASK)));		\
    110 	(F)->lfs_ino_bitmap[(I) >> BMSHIFT] |= (1 << ((I) & BMMASK));	\
    111 } while (0)
    112 #define CLR_BITMAP_FREE(F, I) do { \
    113 	DLOG((DLOG_ALLOC, "lfs: ino %d wrd %d bit %d clr\n", (int)(I), 	\
    114 	     (int)((I) >> BMSHIFT), (int)((I) & BMMASK)));		\
    115 	(F)->lfs_ino_bitmap[(I) >> BMSHIFT] &= ~(1 << ((I) & BMMASK));	\
    116 } while(0)
    117 
    118 #define ISSET_BITMAP_FREE(F, I) \
    119 	((F)->lfs_ino_bitmap[(I) >> BMSHIFT] & (1 << ((I) & BMMASK)))
    120 
    121 /*
    122  * Allocate a particular inode with a particular version number, freeing
    123  * any previous versions of this inode that may have gone before.
    124  * Used by the roll-forward code.
    125  *
    126  * XXX this function does not have appropriate locking to be used on a live fs;
    127  * XXX but something similar could probably be used for an "undelete" call.
    128  *
    129  * Called with the Ifile inode locked.
    130  */
    131 int
    132 lfs_rf_valloc(struct lfs *fs, ino_t ino, int vers, struct lwp *l,
    133 	      struct vnode **vpp)
    134 {
    135 	IFILE *ifp;
    136 	struct buf *bp, *cbp;
    137 	struct vnode *vp;
    138 	struct inode *ip;
    139 	ino_t tino, oldnext;
    140 	int error;
    141 	CLEANERINFO *cip;
    142 
    143 	ASSERT_SEGLOCK(fs); /* XXX it doesn't, really */
    144 
    145 	/*
    146 	 * First, just try a vget. If the version number is the one we want,
    147 	 * we don't have to do anything else.  If the version number is wrong,
    148 	 * take appropriate action.
    149 	 */
    150 	error = VFS_VGET(fs->lfs_ivnode->v_mount, ino, &vp);
    151 	if (error == 0) {
    152 		DLOG((DLOG_RF, "lfs_rf_valloc[1]: ino %d vp %p\n", ino, vp));
    153 
    154 		*vpp = vp;
    155 		ip = VTOI(vp);
    156 		if (ip->i_gen == vers)
    157 			return 0;
    158 		else if (ip->i_gen < vers) {
    159 			lfs_truncate(vp, (off_t)0, 0, NOCRED, l);
    160 			ip->i_gen = ip->i_ffs1_gen = vers;
    161 			LFS_SET_UINO(ip, IN_CHANGE | IN_UPDATE);
    162 			return 0;
    163 		} else {
    164 			DLOG((DLOG_RF, "ino %d: sought version %d, got %d\n",
    165 			       ino, vers, ip->i_ffs1_gen));
    166 			vput(vp);
    167 			*vpp = NULLVP;
    168 			return EEXIST;
    169 		}
    170 	}
    171 
    172 	/*
    173 	 * The inode is not in use.  Find it on the free list.
    174 	 */
    175 	/* If the Ifile is too short to contain this inum, extend it */
    176 	while (VTOI(fs->lfs_ivnode)->i_size <= (ino /
    177 		fs->lfs_ifpb + fs->lfs_cleansz + fs->lfs_segtabsz)
    178 		<< fs->lfs_bshift) {
    179 		extend_ifile(fs, NOCRED);
    180 	}
    181 
    182 	LFS_IENTRY(ifp, fs, ino, bp);
    183 	oldnext = ifp->if_nextfree;
    184 	ifp->if_version = vers;
    185 	brelse(bp);
    186 
    187 	LFS_GET_HEADFREE(fs, cip, cbp, &ino);
    188 	if (ino) {
    189 		LFS_PUT_HEADFREE(fs, cip, cbp, oldnext);
    190 	} else {
    191 		tino = ino;
    192 		while (1) {
    193 			LFS_IENTRY(ifp, fs, tino, bp);
    194 			if (ifp->if_nextfree == ino ||
    195 			    ifp->if_nextfree == LFS_UNUSED_INUM)
    196 				break;
    197 			tino = ifp->if_nextfree;
    198 			brelse(bp);
    199 		}
    200 		if (ifp->if_nextfree == LFS_UNUSED_INUM) {
    201 			brelse(bp);
    202 			return ENOENT;
    203 		}
    204 		ifp->if_nextfree = oldnext;
    205 		LFS_BWRITE_LOG(bp);
    206 	}
    207 
    208 	error = lfs_ialloc(fs, fs->lfs_ivnode, ino, vers, &vp);
    209 	if (error == 0) {
    210 		/*
    211 		 * Make it VREG so we can put blocks on it.  We will change
    212 		 * this later if it turns out to be some other kind of file.
    213 		 */
    214 		ip = VTOI(vp);
    215 		ip->i_mode = ip->i_ffs1_mode = IFREG;
    216 		ip->i_nlink = ip->i_ffs1_nlink = 1;
    217 		ip->i_ffs_effnlink = 1;
    218 		ufs_vinit(vp->v_mount, lfs_specop_p, lfs_fifoop_p, &vp);
    219 		ip = VTOI(vp);
    220 
    221 		DLOG((DLOG_RF, "lfs_rf_valloc: ino %d vp %p\n", ino, vp));
    222 
    223 		/* The dirop-nature of this vnode is past */
    224 		lfs_unmark_vnode(vp);
    225 		(void)lfs_vunref(vp);
    226 		vp->v_flag &= ~VDIROP;
    227 		simple_lock(&fs->lfs_interlock);
    228 		simple_lock(&lfs_subsys_lock);
    229 		--lfs_dirvcount;
    230 		simple_unlock(&lfs_subsys_lock);
    231 		--fs->lfs_dirvcount;
    232 		TAILQ_REMOVE(&fs->lfs_dchainhd, ip, i_lfs_dchain);
    233 		wakeup(&lfs_dirvcount);
    234 		wakeup(&fs->lfs_dirvcount);
    235 		simple_unlock(&fs->lfs_interlock);
    236 	}
    237 	*vpp = vp;
    238 	return error;
    239 }
    240 
    241 /*
    242  * Add a new block to the Ifile, to accommodate future file creations.
    243  * Called with the segment lock held.
    244  */
    245 static int
    246 extend_ifile(struct lfs *fs, kauth_cred_t cred)
    247 {
    248 	struct vnode *vp;
    249 	struct inode *ip;
    250 	IFILE *ifp;
    251 	IFILE_V1 *ifp_v1;
    252 	struct buf *bp, *cbp;
    253 	int error;
    254 	daddr_t i, blkno, xmax;
    255 	ino_t oldlast, maxino;
    256 	CLEANERINFO *cip;
    257 
    258 	ASSERT_SEGLOCK(fs);
    259 
    260 	vp = fs->lfs_ivnode;
    261 	ip = VTOI(vp);
    262 	blkno = lblkno(fs, ip->i_size);
    263 	if ((error = lfs_balloc(vp, ip->i_size, fs->lfs_bsize, cred, 0,
    264 				&bp)) != 0) {
    265 		return (error);
    266 	}
    267 	ip->i_size += fs->lfs_bsize;
    268 	ip->i_ffs1_size = ip->i_size;
    269 	uvm_vnp_setsize(vp, ip->i_size);
    270 
    271 	maxino = ((ip->i_size >> fs->lfs_bshift) - fs->lfs_cleansz -
    272 		  fs->lfs_segtabsz) * fs->lfs_ifpb;
    273 	fs->lfs_ino_bitmap = (lfs_bm_t *)
    274 		realloc(fs->lfs_ino_bitmap, ((maxino + BMMASK) >> BMSHIFT) *
    275 			sizeof(lfs_bm_t), M_SEGMENT, M_WAITOK);
    276 	KASSERT(fs->lfs_ino_bitmap != NULL);
    277 
    278 	i = (blkno - fs->lfs_segtabsz - fs->lfs_cleansz) *
    279 		fs->lfs_ifpb;
    280 
    281 	/*
    282 	 * We insert the new inodes at the head of the free list.
    283 	 * Under normal circumstances, the free list is empty here,
    284 	 * so we are also incidentally placing them at the end (which
    285 	 * we must do if we are to keep them in order).
    286 	 */
    287 	LFS_GET_HEADFREE(fs, cip, cbp, &oldlast);
    288 	LFS_PUT_HEADFREE(fs, cip, cbp, i);
    289 #ifdef DIAGNOSTIC
    290 	if (fs->lfs_freehd == LFS_UNUSED_INUM)
    291 		panic("inode 0 allocated [2]");
    292 #endif /* DIAGNOSTIC */
    293 	xmax = i + fs->lfs_ifpb;
    294 
    295 	if (fs->lfs_version == 1) {
    296 		for (ifp_v1 = (IFILE_V1 *)bp->b_data; i < xmax; ++ifp_v1) {
    297 			SET_BITMAP_FREE(fs, i);
    298 			ifp_v1->if_version = 1;
    299 			ifp_v1->if_daddr = LFS_UNUSED_DADDR;
    300 			ifp_v1->if_nextfree = ++i;
    301 		}
    302 		ifp_v1--;
    303 		ifp_v1->if_nextfree = oldlast;
    304 	} else {
    305 		for (ifp = (IFILE *)bp->b_data; i < xmax; ++ifp) {
    306 			SET_BITMAP_FREE(fs, i);
    307 			ifp->if_version = 1;
    308 			ifp->if_daddr = LFS_UNUSED_DADDR;
    309 			ifp->if_nextfree = ++i;
    310 		}
    311 		ifp--;
    312 		ifp->if_nextfree = oldlast;
    313 	}
    314 	LFS_PUT_TAILFREE(fs, cip, cbp, xmax - 1);
    315 
    316 	(void) LFS_BWRITE_LOG(bp); /* Ifile */
    317 
    318 	return 0;
    319 }
    320 
    321 /* Allocate a new inode. */
    322 /* ARGSUSED */
    323 /* VOP_BWRITE 2i times */
    324 int
    325 lfs_valloc(struct vnode *pvp, int mode, kauth_cred_t cred, struct vnode **vpp)
    326 {
    327 	struct lfs *fs;
    328 	struct buf *bp, *cbp;
    329 	struct ifile *ifp;
    330 	ino_t new_ino;
    331 	int error;
    332 	int new_gen;
    333 	CLEANERINFO *cip;
    334 
    335 	fs = VTOI(pvp)->i_lfs;
    336 	if (fs->lfs_ronly)
    337 		return EROFS;
    338 
    339 	ASSERT_NO_SEGLOCK(fs);
    340 
    341 	lfs_seglock(fs, SEGM_PROT);
    342 	vn_lock(fs->lfs_ivnode, LK_EXCLUSIVE);
    343 
    344 	/* Get the head of the freelist. */
    345 	LFS_GET_HEADFREE(fs, cip, cbp, &new_ino);
    346 	KASSERT(new_ino != LFS_UNUSED_INUM && new_ino != LFS_IFILE_INUM);
    347 
    348 	DLOG((DLOG_ALLOC, "lfs_valloc: allocate inode %lld\n",
    349 	     (long long)new_ino));
    350 
    351 	/*
    352 	 * Remove the inode from the free list and write the new start
    353 	 * of the free list into the superblock.
    354 	 */
    355 	CLR_BITMAP_FREE(fs, new_ino);
    356 	LFS_IENTRY(ifp, fs, new_ino, bp);
    357 	if (ifp->if_daddr != LFS_UNUSED_DADDR)
    358 		panic("lfs_valloc: inuse inode %llu on the free list",
    359 		    (unsigned long long)new_ino);
    360 	LFS_PUT_HEADFREE(fs, cip, cbp, ifp->if_nextfree);
    361 	DLOG((DLOG_ALLOC, "lfs_valloc: headfree %lld -> %lld\n",
    362 	     (long long)new_ino, (long long)ifp->if_nextfree));
    363 
    364 	new_gen = ifp->if_version; /* version was updated by vfree */
    365 	brelse(bp);
    366 
    367 	/* Extend IFILE so that the next lfs_valloc will succeed. */
    368 	if (fs->lfs_freehd == LFS_UNUSED_INUM) {
    369 		if ((error = extend_ifile(fs, cred)) != 0) {
    370 			LFS_PUT_HEADFREE(fs, cip, cbp, new_ino);
    371 			VOP_UNLOCK(fs->lfs_ivnode, 0);
    372 			lfs_segunlock(fs);
    373 			return error;
    374 		}
    375 	}
    376 #ifdef DIAGNOSTIC
    377 	if (fs->lfs_freehd == LFS_UNUSED_INUM)
    378 		panic("inode 0 allocated [3]");
    379 #endif /* DIAGNOSTIC */
    380 
    381 	/* Set superblock modified bit and increment file count. */
    382 	simple_lock(&fs->lfs_interlock);
    383 	fs->lfs_fmod = 1;
    384 	simple_unlock(&fs->lfs_interlock);
    385 	++fs->lfs_nfiles;
    386 
    387 	VOP_UNLOCK(fs->lfs_ivnode, 0);
    388 	lfs_segunlock(fs);
    389 
    390 	return lfs_ialloc(fs, pvp, new_ino, new_gen, vpp);
    391 }
    392 
    393 /*
    394  * Finish allocating a new inode, given an inode and generation number.
    395  */
    396 static int
    397 lfs_ialloc(struct lfs *fs, struct vnode *pvp, ino_t new_ino, int new_gen,
    398 	   struct vnode **vpp)
    399 {
    400 	struct inode *ip;
    401 	struct vnode *vp;
    402 
    403 	ASSERT_NO_SEGLOCK(fs);
    404 
    405 	vp = *vpp;
    406 	lockmgr(&ufs_hashlock, LK_EXCLUSIVE, 0);
    407 	/* Create an inode to associate with the vnode. */
    408 	lfs_vcreate(pvp->v_mount, new_ino, vp);
    409 
    410 	ip = VTOI(vp);
    411 	LFS_SET_UINO(ip, IN_CHANGE);
    412 	/* on-disk structure has been zeroed out by lfs_vcreate */
    413 	ip->i_din.ffs1_din->di_inumber = new_ino;
    414 
    415 	/* Note no blocks yet */
    416 	ip->i_lfs_hiblk = -1;
    417 
    418 	/* Set a new generation number for this inode. */
    419 	if (new_gen) {
    420 		ip->i_gen = new_gen;
    421 		ip->i_ffs1_gen = new_gen;
    422 	}
    423 
    424 	/* Insert into the inode hash table. */
    425 	ufs_ihashins(ip);
    426 	lockmgr(&ufs_hashlock, LK_RELEASE, 0);
    427 
    428 	ufs_vinit(vp->v_mount, lfs_specop_p, lfs_fifoop_p, vpp);
    429 	vp = *vpp;
    430 	ip = VTOI(vp);
    431 
    432 	memset(ip->i_lfs_fragsize, 0, NDADDR * sizeof(*ip->i_lfs_fragsize));
    433 
    434 	uvm_vnp_setsize(vp, 0);
    435 	lfs_mark_vnode(vp);
    436 	genfs_node_init(vp, &lfs_genfsops);
    437 	VREF(ip->i_devvp);
    438 	return (0);
    439 }
    440 
    441 /* Create a new vnode/inode pair and initialize what fields we can. */
    442 void
    443 lfs_vcreate(struct mount *mp, ino_t ino, struct vnode *vp)
    444 {
    445 	struct inode *ip;
    446 	struct ufs1_dinode *dp;
    447 	struct ufsmount *ump;
    448 #ifdef QUOTA
    449 	int i;
    450 #endif
    451 
    452 	/* Get a pointer to the private mount structure. */
    453 	ump = VFSTOUFS(mp);
    454 
    455 	ASSERT_NO_SEGLOCK(ump->um_lfs);
    456 
    457 	/* Initialize the inode. */
    458 	ip = pool_get(&lfs_inode_pool, PR_WAITOK);
    459 	memset(ip, 0, sizeof(*ip));
    460 	dp = pool_get(&lfs_dinode_pool, PR_WAITOK);
    461 	memset(dp, 0, sizeof(*dp));
    462 	ip->inode_ext.lfs = pool_get(&lfs_inoext_pool, PR_WAITOK);
    463 	memset(ip->inode_ext.lfs, 0, sizeof(*ip->inode_ext.lfs));
    464 	vp->v_data = ip;
    465 	ip->i_din.ffs1_din = dp;
    466 	ip->i_ump = ump;
    467 	ip->i_vnode = vp;
    468 	ip->i_devvp = ump->um_devvp;
    469 	ip->i_dev = ump->um_dev;
    470 	ip->i_number = dp->di_inumber = ino;
    471 	ip->i_lfs = ump->um_lfs;
    472 	ip->i_lfs_effnblks = 0;
    473 	SPLAY_INIT(&ip->i_lfs_lbtree);
    474 	ip->i_lfs_nbtree = 0;
    475 	LIST_INIT(&ip->i_lfs_segdhd);
    476 #ifdef QUOTA
    477 	for (i = 0; i < MAXQUOTAS; i++)
    478 		ip->i_dquot[i] = NODQUOT;
    479 #endif
    480 #ifdef DEBUG
    481 	if (ino == LFS_IFILE_INUM)
    482 		vp->v_vnlock->lk_wmesg = "inlock";
    483 #endif
    484 }
    485 
    486 #if 0
    487 /*
    488  * Find the highest-numbered allocated inode.
    489  * This will be used to shrink the Ifile.
    490  */
    491 static inline ino_t
    492 lfs_last_alloc_ino(struct lfs *fs)
    493 {
    494 	ino_t ino, maxino;
    495 
    496 	maxino = ((fs->lfs_ivnode->v_size >> fs->lfs_bshift) -
    497 		  fs->lfs_cleansz - fs->lfs_segtabsz) * fs->lfs_ifpb;
    498 	for (ino = maxino - 1; ino > LFS_UNUSED_INUM; --ino) {
    499 		if (ISSET_BITMAP_FREE(fs, ino) == 0)
    500 			break;
    501 	}
    502 	return ino;
    503 }
    504 #endif
    505 
    506 /*
    507  * Find the previous (next lowest numbered) free inode, if any.
    508  * If there is none, return LFS_UNUSED_INUM.
    509  */
    510 static inline ino_t
    511 lfs_freelist_prev(struct lfs *fs, ino_t ino)
    512 {
    513 	ino_t tino, bound, bb, freehdbb;
    514 
    515 	if (fs->lfs_freehd == LFS_UNUSED_INUM)	 /* No free inodes at all */
    516 		return LFS_UNUSED_INUM;
    517 
    518 	/* Search our own word first */
    519 	bound = ino & ~BMMASK;
    520 	for (tino = ino - 1; tino >= bound && tino > LFS_UNUSED_INUM; tino--)
    521 		if (ISSET_BITMAP_FREE(fs, tino))
    522 			return tino;
    523 	/* If there are no lower words to search, just return */
    524 	if (ino >> BMSHIFT == 0)
    525 		return LFS_UNUSED_INUM;
    526 
    527 	/*
    528 	 * Find a word with a free inode in it.  We have to be a bit
    529 	 * careful here since ino_t is unsigned.
    530 	 */
    531 	freehdbb = (fs->lfs_freehd >> BMSHIFT);
    532 	for (bb = (ino >> BMSHIFT) - 1; bb >= freehdbb && bb > 0; --bb)
    533 		if (fs->lfs_ino_bitmap[bb])
    534 			break;
    535 	if (fs->lfs_ino_bitmap[bb] == 0)
    536 		return LFS_UNUSED_INUM;
    537 
    538 	/* Search the word we found */
    539 	for (tino = (bb << BMSHIFT) | BMMASK; tino >= (bb << BMSHIFT) &&
    540 	     tino > LFS_UNUSED_INUM; tino--)
    541 		if (ISSET_BITMAP_FREE(fs, tino))
    542 			break;
    543 
    544 	if (tino <= LFS_IFILE_INUM)
    545 		tino = LFS_UNUSED_INUM;
    546 
    547 	return tino;
    548 }
    549 
    550 /* Free an inode. */
    551 /* ARGUSED */
    552 /* VOP_BWRITE 2i times */
    553 int
    554 lfs_vfree(struct vnode *vp, ino_t ino, int mode)
    555 {
    556 	SEGUSE *sup;
    557 	CLEANERINFO *cip;
    558 	struct buf *cbp, *bp;
    559 	struct ifile *ifp;
    560 	struct inode *ip;
    561 	struct lfs *fs;
    562 	daddr_t old_iaddr;
    563 	ino_t otail;
    564 	int s;
    565 
    566 	/* Get the inode number and file system. */
    567 	ip = VTOI(vp);
    568 	fs = ip->i_lfs;
    569 	ino = ip->i_number;
    570 
    571 	ASSERT_NO_SEGLOCK(fs);
    572 	DLOG((DLOG_ALLOC, "lfs_vfree: free ino %lld\n", (long long)ino));
    573 
    574 	/* Drain of pending writes */
    575 	simple_lock(&vp->v_interlock);
    576 	s = splbio();
    577 	if (fs->lfs_version > 1 && WRITEINPROG(vp))
    578 		ltsleep(vp, (PRIBIO+1), "lfs_vfree", 0, &vp->v_interlock);
    579 	splx(s);
    580 	simple_unlock(&vp->v_interlock);
    581 
    582 	lfs_seglock(fs, SEGM_PROT);
    583 	vn_lock(fs->lfs_ivnode, LK_EXCLUSIVE);
    584 
    585 	lfs_unmark_vnode(vp);
    586 	if (vp->v_flag & VDIROP) {
    587 		vp->v_flag &= ~VDIROP;
    588 		simple_lock(&fs->lfs_interlock);
    589 		simple_lock(&lfs_subsys_lock);
    590 		--lfs_dirvcount;
    591 		simple_unlock(&lfs_subsys_lock);
    592 		--fs->lfs_dirvcount;
    593 		TAILQ_REMOVE(&fs->lfs_dchainhd, ip, i_lfs_dchain);
    594 		simple_unlock(&fs->lfs_interlock);
    595 		wakeup(&fs->lfs_dirvcount);
    596 		wakeup(&lfs_dirvcount);
    597 		lfs_vunref(vp);
    598 
    599 		/*
    600 		 * If this inode is not going to be written any more, any
    601 		 * segment accounting left over from its truncation needs
    602 		 * to occur at the end of the next dirops flush.  Attach
    603 		 * them to the fs-wide list for that purpose.
    604 		 */
    605 		if (LIST_FIRST(&ip->i_lfs_segdhd) != NULL) {
    606 			struct segdelta *sd;
    607 
    608 			while((sd = LIST_FIRST(&ip->i_lfs_segdhd)) != NULL) {
    609 				LIST_REMOVE(sd, list);
    610 				LIST_INSERT_HEAD(&fs->lfs_segdhd, sd, list);
    611 			}
    612 		}
    613 	} else {
    614 		/*
    615 		 * If it's not a dirop, we can finalize right away.
    616 		 */
    617 		lfs_finalize_ino_seguse(fs, ip);
    618 	}
    619 
    620 	LFS_CLR_UINO(ip, IN_ACCESSED|IN_CLEANING|IN_MODIFIED);
    621 	ip->i_flag &= ~IN_ALLMOD;
    622 	ip->i_lfs_iflags |= LFSI_DELETED;
    623 
    624 	/*
    625 	 * Set the ifile's inode entry to unused, increment its version number
    626 	 * and link it onto the free chain.
    627 	 */
    628 	SET_BITMAP_FREE(fs, ino);
    629 	LFS_IENTRY(ifp, fs, ino, bp);
    630 	old_iaddr = ifp->if_daddr;
    631 	ifp->if_daddr = LFS_UNUSED_DADDR;
    632 	++ifp->if_version;
    633 	if (fs->lfs_version == 1) {
    634 		LFS_GET_HEADFREE(fs, cip, cbp, &(ifp->if_nextfree));
    635 		LFS_PUT_HEADFREE(fs, cip, cbp, ino);
    636 		(void) LFS_BWRITE_LOG(bp); /* Ifile */
    637 	} else {
    638 		ino_t tino, onf;
    639 
    640 		ifp->if_nextfree = LFS_UNUSED_INUM;
    641 		(void) LFS_BWRITE_LOG(bp); /* Ifile */
    642 
    643 		tino = lfs_freelist_prev(fs, ino);
    644 		if (tino == LFS_UNUSED_INUM) {
    645 			/* Nothing free below us, put us on the head */
    646 			LFS_IENTRY(ifp, fs, ino, bp);
    647 			LFS_GET_HEADFREE(fs, cip, cbp, &(ifp->if_nextfree));
    648 			LFS_PUT_HEADFREE(fs, cip, cbp, ino);
    649 			DLOG((DLOG_ALLOC, "lfs_vfree: headfree %lld -> %lld\n",
    650 			     (long long)ifp->if_nextfree, (long long)ino));
    651 			LFS_BWRITE_LOG(bp); /* Ifile */
    652 
    653 			/* If the list was empty, set tail too */
    654 			LFS_GET_TAILFREE(fs, cip, cbp, &otail);
    655 			if (otail == LFS_UNUSED_INUM) {
    656 				LFS_PUT_TAILFREE(fs, cip, cbp, ino);
    657 				DLOG((DLOG_ALLOC, "lfs_vfree: tailfree %lld "
    658 				      "-> %lld\n", (long long)otail,
    659 				      (long long)ino));
    660 			}
    661 		} else {
    662 			/*
    663 			 * Insert this inode into the list after tino.
    664 			 * We hold the segment lock so we don't have to
    665 			 * worry about blocks being written out of order.
    666 			 */
    667 			DLOG((DLOG_ALLOC, "lfs_vfree: insert ino %lld "
    668 			      " after %lld\n", ino, tino));
    669 
    670 			LFS_IENTRY(ifp, fs, tino, bp);
    671 			onf = ifp->if_nextfree;
    672 			ifp->if_nextfree = ino;
    673 			LFS_BWRITE_LOG(bp);	/* Ifile */
    674 
    675 			LFS_IENTRY(ifp, fs, ino, bp);
    676 			ifp->if_nextfree = onf;
    677 			LFS_BWRITE_LOG(bp);	/* Ifile */
    678 
    679 			/* If we're last, put us on the tail */
    680 			if (onf == LFS_UNUSED_INUM) {
    681 				LFS_GET_TAILFREE(fs, cip, cbp, &otail);
    682 				LFS_PUT_TAILFREE(fs, cip, cbp, ino);
    683 				DLOG((DLOG_ALLOC, "lfs_vfree: tailfree %lld "
    684 				      "-> %lld\n", (long long)otail,
    685 				      (long long)ino));
    686 			}
    687 		}
    688 	}
    689 #ifdef DIAGNOSTIC
    690 	if (ino == LFS_UNUSED_INUM) {
    691 		panic("inode 0 freed");
    692 	}
    693 #endif /* DIAGNOSTIC */
    694 	if (old_iaddr != LFS_UNUSED_DADDR) {
    695 		LFS_SEGENTRY(sup, fs, dtosn(fs, old_iaddr), bp);
    696 #ifdef DIAGNOSTIC
    697 		if (sup->su_nbytes < sizeof (struct ufs1_dinode)) {
    698 			printf("lfs_vfree: negative byte count"
    699 			       " (segment %" PRIu32 " short by %d)\n",
    700 			       dtosn(fs, old_iaddr),
    701 			       (int)sizeof (struct ufs1_dinode) -
    702 				    sup->su_nbytes);
    703 			panic("lfs_vfree: negative byte count");
    704 			sup->su_nbytes = sizeof (struct ufs1_dinode);
    705 		}
    706 #endif
    707 		sup->su_nbytes -= sizeof (struct ufs1_dinode);
    708 		LFS_WRITESEGENTRY(sup, fs, dtosn(fs, old_iaddr), bp); /* Ifile */
    709 	}
    710 
    711 	/* Set superblock modified bit and decrement file count. */
    712 	simple_lock(&fs->lfs_interlock);
    713 	fs->lfs_fmod = 1;
    714 	simple_unlock(&fs->lfs_interlock);
    715 	--fs->lfs_nfiles;
    716 
    717 	VOP_UNLOCK(fs->lfs_ivnode, 0);
    718 	lfs_segunlock(fs);
    719 
    720 	return (0);
    721 }
    722 
    723 /*
    724  * Sort the freelist and set up the free-inode bitmap.
    725  * To be called by lfs_mountfs().
    726  */
    727 void
    728 lfs_order_freelist(struct lfs *fs)
    729 {
    730 	CLEANERINFO *cip;
    731 	IFILE *ifp = NULL;
    732 	struct buf *bp;
    733 	ino_t ino, firstino, lastino, maxino;
    734 
    735 	maxino = ((fs->lfs_ivnode->v_size >> fs->lfs_bshift) -
    736 		  fs->lfs_cleansz - fs->lfs_segtabsz) * fs->lfs_ifpb;
    737 	fs->lfs_ino_bitmap = (lfs_bm_t *)
    738 		malloc(((maxino + BMMASK) >> BMSHIFT) * sizeof(lfs_bm_t),
    739 		       M_SEGMENT, M_WAITOK | M_ZERO);
    740 	KASSERT(fs->lfs_ino_bitmap != NULL);
    741 
    742 	firstino = lastino = LFS_UNUSED_INUM;
    743 	for (ino = 0; ino < maxino; ino++) {
    744 		if (ino % fs->lfs_ifpb == 0)
    745 			LFS_IENTRY(ifp, fs, ino, bp);
    746 		else
    747 			++ifp;
    748 
    749 		/* Don't put zero or ifile on the free list */
    750 		if (ino == LFS_UNUSED_INUM || ino == LFS_IFILE_INUM)
    751 			continue;
    752 
    753 		if (ifp->if_daddr == LFS_UNUSED_DADDR) {
    754 			if (firstino == LFS_UNUSED_INUM)
    755 				firstino = ino;
    756 			else {
    757 				brelse(bp);
    758 
    759 				LFS_IENTRY(ifp, fs, lastino, bp);
    760 				ifp->if_nextfree = ino;
    761 				LFS_BWRITE_LOG(bp);
    762 
    763 				LFS_IENTRY(ifp, fs, ino, bp);
    764 			}
    765 			lastino = ino;
    766 
    767 			SET_BITMAP_FREE(fs, ino);
    768 		}
    769 
    770 		if ((ino + 1) % fs->lfs_ifpb == 0)
    771 			brelse(bp);
    772 	}
    773 
    774 	LFS_PUT_HEADFREE(fs, cip, bp, firstino);
    775 	LFS_PUT_TAILFREE(fs, cip, bp, lastino);
    776 }
    777