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lfs_vfsops.c revision 1.307
      1 /*	$NetBSD: lfs_vfsops.c,v 1.307 2013/06/18 18:18:58 christos Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 1999, 2000, 2001, 2002, 2003, 2007, 2007
      5  *     The NetBSD Foundation, Inc.
      6  * All rights reserved.
      7  *
      8  * This code is derived from software contributed to The NetBSD Foundation
      9  * by Konrad E. Schroder <perseant (at) hhhh.org>.
     10  *
     11  * Redistribution and use in source and binary forms, with or without
     12  * modification, are permitted provided that the following conditions
     13  * are met:
     14  * 1. Redistributions of source code must retain the above copyright
     15  *    notice, this list of conditions and the following disclaimer.
     16  * 2. Redistributions in binary form must reproduce the above copyright
     17  *    notice, this list of conditions and the following disclaimer in the
     18  *    documentation and/or other materials provided with the distribution.
     19  *
     20  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     22  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     23  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     24  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     25  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     26  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     27  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     28  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     29  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     30  * POSSIBILITY OF SUCH DAMAGE.
     31  */
     32 /*-
     33  * Copyright (c) 1989, 1991, 1993, 1994
     34  *	The Regents of the University of California.  All rights reserved.
     35  *
     36  * Redistribution and use in source and binary forms, with or without
     37  * modification, are permitted provided that the following conditions
     38  * are met:
     39  * 1. Redistributions of source code must retain the above copyright
     40  *    notice, this list of conditions and the following disclaimer.
     41  * 2. Redistributions in binary form must reproduce the above copyright
     42  *    notice, this list of conditions and the following disclaimer in the
     43  *    documentation and/or other materials provided with the distribution.
     44  * 3. Neither the name of the University nor the names of its contributors
     45  *    may be used to endorse or promote products derived from this software
     46  *    without specific prior written permission.
     47  *
     48  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     49  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     50  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     51  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     52  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     53  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     54  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     55  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     56  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     57  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     58  * SUCH DAMAGE.
     59  *
     60  *	@(#)lfs_vfsops.c	8.20 (Berkeley) 6/10/95
     61  */
     62 
     63 #include <sys/cdefs.h>
     64 __KERNEL_RCSID(0, "$NetBSD: lfs_vfsops.c,v 1.307 2013/06/18 18:18:58 christos Exp $");
     65 
     66 #if defined(_KERNEL_OPT)
     67 #include "opt_lfs.h"
     68 #include "opt_quota.h"
     69 #endif
     70 
     71 #include <sys/param.h>
     72 #include <sys/systm.h>
     73 #include <sys/namei.h>
     74 #include <sys/proc.h>
     75 #include <sys/kernel.h>
     76 #include <sys/vnode.h>
     77 #include <sys/mount.h>
     78 #include <sys/kthread.h>
     79 #include <sys/buf.h>
     80 #include <sys/device.h>
     81 #include <sys/mbuf.h>
     82 #include <sys/file.h>
     83 #include <sys/disklabel.h>
     84 #include <sys/ioctl.h>
     85 #include <sys/errno.h>
     86 #include <sys/malloc.h>
     87 #include <sys/pool.h>
     88 #include <sys/socket.h>
     89 #include <sys/syslog.h>
     90 #include <uvm/uvm_extern.h>
     91 #include <sys/sysctl.h>
     92 #include <sys/conf.h>
     93 #include <sys/kauth.h>
     94 #include <sys/module.h>
     95 #include <sys/syscallvar.h>
     96 #include <sys/syscall.h>
     97 #include <sys/syscallargs.h>
     98 
     99 #include <miscfs/specfs/specdev.h>
    100 
    101 #include <ufs/lfs/ulfs_quotacommon.h>
    102 #include <ufs/lfs/ulfs_inode.h>
    103 #include <ufs/lfs/ulfsmount.h>
    104 #include <ufs/lfs/ulfs_extern.h>
    105 
    106 #include <uvm/uvm.h>
    107 #include <uvm/uvm_stat.h>
    108 #include <uvm/uvm_pager.h>
    109 #include <uvm/uvm_pdaemon.h>
    110 
    111 #include <ufs/lfs/lfs.h>
    112 #include <ufs/lfs/lfs_extern.h>
    113 
    114 #include <miscfs/genfs/genfs.h>
    115 #include <miscfs/genfs/genfs_node.h>
    116 
    117 MODULE(MODULE_CLASS_VFS, lfs, NULL);
    118 
    119 static int lfs_gop_write(struct vnode *, struct vm_page **, int, int);
    120 static bool lfs_issequential_hole(const struct ulfsmount *,
    121     daddr_t, daddr_t);
    122 
    123 static int lfs_mountfs(struct vnode *, struct mount *, struct lwp *);
    124 
    125 static struct sysctllog *lfs_sysctl_log;
    126 
    127 extern const struct vnodeopv_desc lfs_vnodeop_opv_desc;
    128 extern const struct vnodeopv_desc lfs_specop_opv_desc;
    129 extern const struct vnodeopv_desc lfs_fifoop_opv_desc;
    130 
    131 pid_t lfs_writer_daemon = 0;
    132 lwpid_t lfs_writer_lid = 0;
    133 int lfs_do_flush = 0;
    134 #ifdef LFS_KERNEL_RFW
    135 int lfs_do_rfw = 0;
    136 #endif
    137 
    138 const struct vnodeopv_desc * const lfs_vnodeopv_descs[] = {
    139 	&lfs_vnodeop_opv_desc,
    140 	&lfs_specop_opv_desc,
    141 	&lfs_fifoop_opv_desc,
    142 	NULL,
    143 };
    144 
    145 struct vfsops lfs_vfsops = {
    146 	MOUNT_LFS,
    147 	sizeof (struct ulfs_args),
    148 	lfs_mount,
    149 	ulfs_start,
    150 	lfs_unmount,
    151 	ulfs_root,
    152 	ulfs_quotactl,
    153 	lfs_statvfs,
    154 	lfs_sync,
    155 	lfs_vget,
    156 	lfs_fhtovp,
    157 	lfs_vptofh,
    158 	lfs_init,
    159 	lfs_reinit,
    160 	lfs_done,
    161 	lfs_mountroot,
    162 	(int (*)(struct mount *, struct vnode *, struct timespec *)) eopnotsupp,
    163 	vfs_stdextattrctl,
    164 	(void *)eopnotsupp,	/* vfs_suspendctl */
    165 	genfs_renamelock_enter,
    166 	genfs_renamelock_exit,
    167 	(void *)eopnotsupp,
    168 	lfs_vnodeopv_descs,
    169 	0,
    170 	{ NULL, NULL },
    171 };
    172 
    173 const struct genfs_ops lfs_genfsops = {
    174 	.gop_size = lfs_gop_size,
    175 	.gop_alloc = ulfs_gop_alloc,
    176 	.gop_write = lfs_gop_write,
    177 	.gop_markupdate = ulfs_gop_markupdate,
    178 };
    179 
    180 static const struct ulfs_ops lfs_ulfsops = {
    181 	.uo_itimes = NULL,
    182 	.uo_update = lfs_update,
    183 	.uo_truncate = lfs_truncate,
    184 	.uo_valloc = lfs_valloc,
    185 	.uo_vfree = lfs_vfree,
    186 	.uo_balloc = lfs_balloc,
    187 	.uo_unmark_vnode = lfs_unmark_vnode,
    188 };
    189 
    190 struct shortlong {
    191 	const char *sname;
    192 	const char *lname;
    193 };
    194 
    195 static int
    196 sysctl_lfs_dostats(SYSCTLFN_ARGS)
    197 {
    198 	extern struct lfs_stats lfs_stats;
    199 	extern int lfs_dostats;
    200 	int error;
    201 
    202 	error = sysctl_lookup(SYSCTLFN_CALL(rnode));
    203 	if (error || newp == NULL)
    204 		return (error);
    205 
    206 	if (lfs_dostats == 0)
    207 		memset(&lfs_stats, 0, sizeof(lfs_stats));
    208 
    209 	return (0);
    210 }
    211 
    212 static void
    213 lfs_sysctl_setup(struct sysctllog **clog)
    214 {
    215 	int i;
    216 	extern int lfs_writeindir, lfs_dostats, lfs_clean_vnhead,
    217 		   lfs_fs_pagetrip, lfs_ignore_lazy_sync;
    218 #ifdef DEBUG
    219 	extern int lfs_debug_log_subsys[DLOG_MAX];
    220 	struct shortlong dlog_names[DLOG_MAX] = { /* Must match lfs.h ! */
    221 		{ "rollforward", "Debug roll-forward code" },
    222 		{ "alloc",	"Debug inode allocation and free list" },
    223 		{ "avail",	"Debug space-available-now accounting" },
    224 		{ "flush",	"Debug flush triggers" },
    225 		{ "lockedlist",	"Debug locked list accounting" },
    226 		{ "vnode_verbose", "Verbose per-vnode-written debugging" },
    227 		{ "vnode",	"Debug vnode use during segment write" },
    228 		{ "segment",	"Debug segment writing" },
    229 		{ "seguse",	"Debug segment used-bytes accounting" },
    230 		{ "cleaner",	"Debug cleaning routines" },
    231 		{ "mount",	"Debug mount/unmount routines" },
    232 		{ "pagecache",	"Debug UBC interactions" },
    233 		{ "dirop",	"Debug directory-operation accounting" },
    234 		{ "malloc",	"Debug private malloc accounting" },
    235 	};
    236 #endif /* DEBUG */
    237 	struct shortlong stat_names[] = { /* Must match lfs.h! */
    238 		{ "segsused",	    "Number of new segments allocated" },
    239 		{ "psegwrites",	    "Number of partial-segment writes" },
    240 		{ "psyncwrites",    "Number of synchronous partial-segment"
    241 				    " writes" },
    242 		{ "pcleanwrites",   "Number of partial-segment writes by the"
    243 				    " cleaner" },
    244 		{ "blocktot",       "Number of blocks written" },
    245 		{ "cleanblocks",    "Number of blocks written by the cleaner" },
    246 		{ "ncheckpoints",   "Number of checkpoints made" },
    247 		{ "nwrites",        "Number of whole writes" },
    248 		{ "nsync_writes",   "Number of synchronous writes" },
    249 		{ "wait_exceeded",  "Number of times writer waited for"
    250 				    " cleaner" },
    251 		{ "write_exceeded", "Number of times writer invoked flush" },
    252 		{ "flush_invoked",  "Number of times flush was invoked" },
    253 		{ "vflush_invoked", "Number of time vflush was called" },
    254 		{ "clean_inlocked", "Number of vnodes skipped for VI_XLOCK" },
    255 		{ "clean_vnlocked", "Number of vnodes skipped for vget failure" },
    256 		{ "segs_reclaimed", "Number of segments reclaimed" },
    257 	};
    258 
    259 	sysctl_createv(clog, 0, NULL, NULL,
    260 		       CTLFLAG_PERMANENT,
    261 		       CTLTYPE_NODE, "vfs", NULL,
    262 		       NULL, 0, NULL, 0,
    263 		       CTL_VFS, CTL_EOL);
    264 	sysctl_createv(clog, 0, NULL, NULL,
    265 		       CTLFLAG_PERMANENT,
    266 		       CTLTYPE_NODE, "lfs",
    267 		       SYSCTL_DESCR("Log-structured file system"),
    268 		       NULL, 0, NULL, 0,
    269 		       CTL_VFS, 5, CTL_EOL);
    270 	/*
    271 	 * XXX the "5" above could be dynamic, thereby eliminating one
    272 	 * more instance of the "number to vfs" mapping problem, but
    273 	 * "5" is the order as taken from sys/mount.h
    274 	 */
    275 
    276 	sysctl_createv(clog, 0, NULL, NULL,
    277 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
    278 		       CTLTYPE_INT, "flushindir", NULL,
    279 		       NULL, 0, &lfs_writeindir, 0,
    280 		       CTL_VFS, 5, LFS_WRITEINDIR, CTL_EOL);
    281 	sysctl_createv(clog, 0, NULL, NULL,
    282 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
    283 		       CTLTYPE_INT, "clean_vnhead", NULL,
    284 		       NULL, 0, &lfs_clean_vnhead, 0,
    285 		       CTL_VFS, 5, LFS_CLEAN_VNHEAD, CTL_EOL);
    286 	sysctl_createv(clog, 0, NULL, NULL,
    287 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
    288 		       CTLTYPE_INT, "dostats",
    289 		       SYSCTL_DESCR("Maintain statistics on LFS operations"),
    290 		       sysctl_lfs_dostats, 0, &lfs_dostats, 0,
    291 		       CTL_VFS, 5, LFS_DOSTATS, CTL_EOL);
    292 	sysctl_createv(clog, 0, NULL, NULL,
    293 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
    294 		       CTLTYPE_INT, "pagetrip",
    295 		       SYSCTL_DESCR("How many dirty pages in fs triggers"
    296 				    " a flush"),
    297 		       NULL, 0, &lfs_fs_pagetrip, 0,
    298 		       CTL_VFS, 5, LFS_FS_PAGETRIP, CTL_EOL);
    299 	sysctl_createv(clog, 0, NULL, NULL,
    300 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
    301 		       CTLTYPE_INT, "ignore_lazy_sync",
    302 		       SYSCTL_DESCR("Lazy Sync is ignored entirely"),
    303 		       NULL, 0, &lfs_ignore_lazy_sync, 0,
    304 		       CTL_VFS, 5, LFS_IGNORE_LAZY_SYNC, CTL_EOL);
    305 #ifdef LFS_KERNEL_RFW
    306 	sysctl_createv(clog, 0, NULL, NULL,
    307 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
    308 		       CTLTYPE_INT, "rfw",
    309 		       SYSCTL_DESCR("Use in-kernel roll-forward on mount"),
    310 		       NULL, 0, &lfs_do_rfw, 0,
    311 		       CTL_VFS, 5, LFS_DO_RFW, CTL_EOL);
    312 #endif
    313 
    314 	sysctl_createv(clog, 0, NULL, NULL,
    315 		       CTLFLAG_PERMANENT,
    316 		       CTLTYPE_NODE, "stats",
    317 		       SYSCTL_DESCR("Debugging options"),
    318 		       NULL, 0, NULL, 0,
    319 		       CTL_VFS, 5, LFS_STATS, CTL_EOL);
    320 	for (i = 0; i < sizeof(struct lfs_stats) / sizeof(u_int); i++) {
    321 		sysctl_createv(clog, 0, NULL, NULL,
    322 			       CTLFLAG_PERMANENT|CTLFLAG_READONLY,
    323 			       CTLTYPE_INT, stat_names[i].sname,
    324 			       SYSCTL_DESCR(stat_names[i].lname),
    325 			       NULL, 0, &(((u_int *)&lfs_stats.segsused)[i]),
    326 			       0, CTL_VFS, 5, LFS_STATS, i, CTL_EOL);
    327 	}
    328 
    329 #ifdef DEBUG
    330 	sysctl_createv(clog, 0, NULL, NULL,
    331 		       CTLFLAG_PERMANENT,
    332 		       CTLTYPE_NODE, "debug",
    333 		       SYSCTL_DESCR("Debugging options"),
    334 		       NULL, 0, NULL, 0,
    335 		       CTL_VFS, 5, LFS_DEBUGLOG, CTL_EOL);
    336 	for (i = 0; i < DLOG_MAX; i++) {
    337 		sysctl_createv(clog, 0, NULL, NULL,
    338 			       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
    339 			       CTLTYPE_INT, dlog_names[i].sname,
    340 			       SYSCTL_DESCR(dlog_names[i].lname),
    341 			       NULL, 0, &(lfs_debug_log_subsys[i]), 0,
    342 			       CTL_VFS, 5, LFS_DEBUGLOG, i, CTL_EOL);
    343 	}
    344 #endif
    345 }
    346 
    347 /* old cleaner syscall interface.  see VOP_FCNTL() */
    348 static const struct syscall_package lfs_syscalls[] = {
    349 	{ SYS_lfs_bmapv,	0, (sy_call_t *)sys_lfs_bmapv		},
    350 	{ SYS_lfs_markv,	0, (sy_call_t *)sys_lfs_markv		},
    351 	{ SYS_lfs_segclean,	0, (sy_call_t *)sys___lfs_segwait50	},
    352 	{ 0, 0, NULL },
    353 };
    354 
    355 static int
    356 lfs_modcmd(modcmd_t cmd, void *arg)
    357 {
    358 	int error;
    359 
    360 	switch (cmd) {
    361 	case MODULE_CMD_INIT:
    362 		error = syscall_establish(NULL, lfs_syscalls);
    363 		if (error)
    364 			return error;
    365 		error = vfs_attach(&lfs_vfsops);
    366 		if (error != 0) {
    367 			syscall_disestablish(NULL, lfs_syscalls);
    368 			break;
    369 		}
    370 		lfs_sysctl_setup(&lfs_sysctl_log);
    371 		break;
    372 	case MODULE_CMD_FINI:
    373 		error = vfs_detach(&lfs_vfsops);
    374 		if (error != 0)
    375 			break;
    376 		syscall_disestablish(NULL, lfs_syscalls);
    377 		sysctl_teardown(&lfs_sysctl_log);
    378 		break;
    379 	default:
    380 		error = ENOTTY;
    381 		break;
    382 	}
    383 
    384 	return (error);
    385 }
    386 
    387 /*
    388  * XXX Same structure as FFS inodes?  Should we share a common pool?
    389  */
    390 struct pool lfs_inode_pool;
    391 struct pool lfs_dinode_pool;
    392 struct pool lfs_inoext_pool;
    393 struct pool lfs_lbnentry_pool;
    394 
    395 /*
    396  * The writer daemon.  UVM keeps track of how many dirty pages we are holding
    397  * in lfs_subsys_pages; the daemon flushes the filesystem when this value
    398  * crosses the (user-defined) threshhold LFS_MAX_PAGES.
    399  */
    400 static void
    401 lfs_writerd(void *arg)
    402 {
    403  	struct mount *mp, *nmp;
    404  	struct lfs *fs;
    405 	struct vfsops *vfs = NULL;
    406  	int fsflags;
    407  	int loopcount;
    408 	int skipc;
    409 	int lfsc;
    410 	int wrote_something = 0;
    411 
    412 	mutex_enter(&lfs_lock);
    413  	lfs_writer_daemon = curproc->p_pid;
    414 	lfs_writer_lid = curlwp->l_lid;
    415 	mutex_exit(&lfs_lock);
    416 
    417 	/* Take an extra reference to the LFS vfsops. */
    418 	vfs = vfs_getopsbyname(MOUNT_LFS);
    419 
    420  	mutex_enter(&lfs_lock);
    421  	for (;;) {
    422 		KASSERT(mutex_owned(&lfs_lock));
    423 		if (wrote_something == 0)
    424 			mtsleep(&lfs_writer_daemon, PVM, "lfswriter", hz/10 + 1,
    425 				&lfs_lock);
    426 
    427 		KASSERT(mutex_owned(&lfs_lock));
    428 		loopcount = 0;
    429 		wrote_something = 0;
    430 
    431 		/*
    432 		 * If global state wants a flush, flush everything.
    433 		 */
    434 		if (lfs_do_flush || locked_queue_count > LFS_MAX_BUFS ||
    435 			locked_queue_bytes > LFS_MAX_BYTES ||
    436 			lfs_subsys_pages > LFS_MAX_PAGES) {
    437 
    438 			if (lfs_do_flush) {
    439 				DLOG((DLOG_FLUSH, "lfs_writerd: lfs_do_flush\n"));
    440 			}
    441 			if (locked_queue_count > LFS_MAX_BUFS) {
    442 				DLOG((DLOG_FLUSH, "lfs_writerd: lqc = %d, max %d\n",
    443 				      locked_queue_count, LFS_MAX_BUFS));
    444 			}
    445 			if (locked_queue_bytes > LFS_MAX_BYTES) {
    446 				DLOG((DLOG_FLUSH, "lfs_writerd: lqb = %ld, max %ld\n",
    447 				      locked_queue_bytes, LFS_MAX_BYTES));
    448 			}
    449 			if (lfs_subsys_pages > LFS_MAX_PAGES) {
    450 				DLOG((DLOG_FLUSH, "lfs_writerd: lssp = %d, max %d\n",
    451 				      lfs_subsys_pages, LFS_MAX_PAGES));
    452 			}
    453 
    454 			lfs_flush(NULL, SEGM_WRITERD, 0);
    455 			lfs_do_flush = 0;
    456 			KASSERT(mutex_owned(&lfs_lock));
    457 			continue;
    458 		}
    459 		KASSERT(mutex_owned(&lfs_lock));
    460 		mutex_exit(&lfs_lock);
    461 
    462  		/*
    463  		 * Look through the list of LFSs to see if any of them
    464  		 * have requested pageouts.
    465  		 */
    466  		mutex_enter(&mountlist_lock);
    467 		lfsc = 0;
    468 		skipc = 0;
    469  		for (mp = CIRCLEQ_FIRST(&mountlist); mp != (void *)&mountlist;
    470  		     mp = nmp) {
    471  			if (vfs_busy(mp, &nmp)) {
    472 				++skipc;
    473  				continue;
    474  			}
    475 			KASSERT(!mutex_owned(&lfs_lock));
    476  			if (strncmp(mp->mnt_stat.f_fstypename, MOUNT_LFS,
    477  			    sizeof(mp->mnt_stat.f_fstypename)) == 0) {
    478 				++lfsc;
    479  				fs = VFSTOULFS(mp)->um_lfs;
    480 				int32_t ooffset = 0;
    481 				fsflags = SEGM_SINGLE;
    482 
    483  				mutex_enter(&lfs_lock);
    484 				ooffset = fs->lfs_offset;
    485 
    486 				if (fs->lfs_nextseg < fs->lfs_curseg && fs->lfs_nowrap) {
    487 					/* Don't try to write if we're suspended */
    488 					mutex_exit(&lfs_lock);
    489 					vfs_unbusy(mp, false, &nmp);
    490 					continue;
    491 				}
    492 				if (LFS_STARVED_FOR_SEGS(fs)) {
    493 					mutex_exit(&lfs_lock);
    494 
    495 					DLOG((DLOG_FLUSH, "lfs_writerd: need cleaning before writing possible\n"));
    496 					lfs_wakeup_cleaner(fs);
    497 					vfs_unbusy(mp, false, &nmp);
    498 					continue;
    499 				}
    500 
    501  				if ((fs->lfs_dirvcount > LFS_MAX_FSDIROP(fs) ||
    502  				     lfs_dirvcount > LFS_MAX_DIROP) &&
    503 				    fs->lfs_dirops == 0) {
    504 					fsflags &= ~SEGM_SINGLE;
    505  					fsflags |= SEGM_CKP;
    506 					DLOG((DLOG_FLUSH, "lfs_writerd: checkpoint\n"));
    507 					lfs_flush_fs(fs, fsflags);
    508 				} else if (fs->lfs_pdflush) {
    509  					DLOG((DLOG_FLUSH, "lfs_writerd: pdflush set\n"));
    510  					lfs_flush_fs(fs, fsflags);
    511  				} else if (!TAILQ_EMPTY(&fs->lfs_pchainhd)) {
    512  					DLOG((DLOG_FLUSH, "lfs_writerd: pchain non-empty\n"));
    513  					mutex_exit(&lfs_lock);
    514  					lfs_writer_enter(fs, "wrdirop");
    515  					lfs_flush_pchain(fs);
    516  					lfs_writer_leave(fs);
    517 					mutex_enter(&lfs_lock);
    518 				}
    519 				if (fs->lfs_offset != ooffset)
    520 					++wrote_something;
    521 				mutex_exit(&lfs_lock);
    522  			}
    523 			KASSERT(!mutex_owned(&lfs_lock));
    524  			vfs_unbusy(mp, false, &nmp);
    525  		}
    526 		if (lfsc + skipc == 0) {
    527 			mutex_enter(&lfs_lock);
    528 			lfs_writer_daemon = 0;
    529 			lfs_writer_lid = 0;
    530 			mutex_exit(&lfs_lock);
    531 			mutex_exit(&mountlist_lock);
    532 			break;
    533 		}
    534  		mutex_exit(&mountlist_lock);
    535 
    536  		mutex_enter(&lfs_lock);
    537  	}
    538 	KASSERT(!mutex_owned(&lfs_lock));
    539 	KASSERT(!mutex_owned(&mountlist_lock));
    540 
    541 	/* Give up our extra reference so the module can be unloaded. */
    542 	mutex_enter(&vfs_list_lock);
    543 	if (vfs != NULL)
    544 		vfs->vfs_refcount--;
    545 	mutex_exit(&vfs_list_lock);
    546 
    547 	/* Done! */
    548 	kthread_exit(0);
    549 }
    550 
    551 /*
    552  * Initialize the filesystem, most work done by ulfs_init.
    553  */
    554 void
    555 lfs_init(void)
    556 {
    557 
    558 	malloc_type_attach(M_SEGMENT);
    559 	pool_init(&lfs_inode_pool, sizeof(struct inode), 0, 0, 0,
    560 	    "lfsinopl", &pool_allocator_nointr, IPL_NONE);
    561 	pool_init(&lfs_dinode_pool, sizeof(struct ulfs1_dinode), 0, 0, 0,
    562 	    "lfsdinopl", &pool_allocator_nointr, IPL_NONE);
    563 	pool_init(&lfs_inoext_pool, sizeof(struct lfs_inode_ext), 8, 0, 0,
    564 	    "lfsinoextpl", &pool_allocator_nointr, IPL_NONE);
    565 	pool_init(&lfs_lbnentry_pool, sizeof(struct lbnentry), 0, 0, 0,
    566 	    "lfslbnpool", &pool_allocator_nointr, IPL_NONE);
    567 	ulfs_init();
    568 
    569 #ifdef DEBUG
    570 	memset(lfs_log, 0, sizeof(lfs_log));
    571 #endif
    572 	mutex_init(&lfs_lock, MUTEX_DEFAULT, IPL_NONE);
    573 	cv_init(&locked_queue_cv, "lfsbuf");
    574 	cv_init(&lfs_writing_cv, "lfsflush");
    575 }
    576 
    577 void
    578 lfs_reinit(void)
    579 {
    580 	ulfs_reinit();
    581 }
    582 
    583 void
    584 lfs_done(void)
    585 {
    586 	ulfs_done();
    587 	mutex_destroy(&lfs_lock);
    588 	cv_destroy(&locked_queue_cv);
    589 	cv_destroy(&lfs_writing_cv);
    590 	pool_destroy(&lfs_inode_pool);
    591 	pool_destroy(&lfs_dinode_pool);
    592 	pool_destroy(&lfs_inoext_pool);
    593 	pool_destroy(&lfs_lbnentry_pool);
    594 	malloc_type_detach(M_SEGMENT);
    595 }
    596 
    597 /*
    598  * Called by main() when ulfs is going to be mounted as root.
    599  */
    600 int
    601 lfs_mountroot(void)
    602 {
    603 	extern struct vnode *rootvp;
    604 	struct lfs *fs = NULL;				/* LFS */
    605 	struct mount *mp;
    606 	struct lwp *l = curlwp;
    607 	struct ulfsmount *ump;
    608 	int error;
    609 
    610 	if (device_class(root_device) != DV_DISK)
    611 		return (ENODEV);
    612 
    613 	if (rootdev == NODEV)
    614 		return (ENODEV);
    615 	if ((error = vfs_rootmountalloc(MOUNT_LFS, "root_device", &mp))) {
    616 		vrele(rootvp);
    617 		return (error);
    618 	}
    619 	if ((error = lfs_mountfs(rootvp, mp, l))) {
    620 		vfs_unbusy(mp, false, NULL);
    621 		vfs_destroy(mp);
    622 		return (error);
    623 	}
    624 	mutex_enter(&mountlist_lock);
    625 	CIRCLEQ_INSERT_TAIL(&mountlist, mp, mnt_list);
    626 	mutex_exit(&mountlist_lock);
    627 	ump = VFSTOULFS(mp);
    628 	fs = ump->um_lfs;
    629 	memset(fs->lfs_fsmnt, 0, sizeof(fs->lfs_fsmnt));
    630 	(void)copystr(mp->mnt_stat.f_mntonname, fs->lfs_fsmnt, MNAMELEN - 1, 0);
    631 	(void)lfs_statvfs(mp, &mp->mnt_stat);
    632 	vfs_unbusy(mp, false, NULL);
    633 	setrootfstime((time_t)(VFSTOULFS(mp)->um_lfs->lfs_tstamp));
    634 	return (0);
    635 }
    636 
    637 /*
    638  * VFS Operations.
    639  *
    640  * mount system call
    641  */
    642 int
    643 lfs_mount(struct mount *mp, const char *path, void *data, size_t *data_len)
    644 {
    645 	struct lwp *l = curlwp;
    646 	struct vnode *devvp;
    647 	struct ulfs_args *args = data;
    648 	struct ulfsmount *ump = NULL;
    649 	struct lfs *fs = NULL;				/* LFS */
    650 	int error = 0, update;
    651 	mode_t accessmode;
    652 
    653 	if (*data_len < sizeof *args)
    654 		return EINVAL;
    655 
    656 	if (mp->mnt_flag & MNT_GETARGS) {
    657 		ump = VFSTOULFS(mp);
    658 		if (ump == NULL)
    659 			return EIO;
    660 		args->fspec = NULL;
    661 		*data_len = sizeof *args;
    662 		return 0;
    663 	}
    664 
    665 	update = mp->mnt_flag & MNT_UPDATE;
    666 
    667 	/* Check arguments */
    668 	if (args->fspec != NULL) {
    669 		/*
    670 		 * Look up the name and verify that it's sane.
    671 		 */
    672 		error = namei_simple_user(args->fspec,
    673 					NSM_FOLLOW_NOEMULROOT, &devvp);
    674 		if (error != 0)
    675 			return (error);
    676 
    677 		if (!update) {
    678 			/*
    679 			 * Be sure this is a valid block device
    680 			 */
    681 			if (devvp->v_type != VBLK)
    682 				error = ENOTBLK;
    683 			else if (bdevsw_lookup(devvp->v_rdev) == NULL)
    684 				error = ENXIO;
    685 		} else {
    686 			/*
    687 			 * Be sure we're still naming the same device
    688 			 * used for our initial mount
    689 			 */
    690 			ump = VFSTOULFS(mp);
    691 			if (devvp != ump->um_devvp) {
    692 				if (devvp->v_rdev != ump->um_devvp->v_rdev)
    693 					error = EINVAL;
    694 				else {
    695 					vrele(devvp);
    696 					devvp = ump->um_devvp;
    697 					vref(devvp);
    698 				}
    699 			}
    700 		}
    701 	} else {
    702 		if (!update) {
    703 			/* New mounts must have a filename for the device */
    704 			return (EINVAL);
    705 		} else {
    706 			/* Use the extant mount */
    707 			ump = VFSTOULFS(mp);
    708 			devvp = ump->um_devvp;
    709 			vref(devvp);
    710 		}
    711 	}
    712 
    713 
    714 	/*
    715 	 * If mount by non-root, then verify that user has necessary
    716 	 * permissions on the device.
    717 	 */
    718 	if (error == 0) {
    719 		accessmode = VREAD;
    720 		if (update ?
    721 		    (mp->mnt_iflag & IMNT_WANTRDWR) != 0 :
    722 		    (mp->mnt_flag & MNT_RDONLY) == 0)
    723 			accessmode |= VWRITE;
    724 		vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY);
    725 		error = kauth_authorize_system(l->l_cred, KAUTH_SYSTEM_MOUNT,
    726 		    KAUTH_REQ_SYSTEM_MOUNT_DEVICE, mp, devvp,
    727 		    KAUTH_ARG(accessmode));
    728 		VOP_UNLOCK(devvp);
    729 	}
    730 
    731 	if (error) {
    732 		vrele(devvp);
    733 		return (error);
    734 	}
    735 
    736 	if (!update) {
    737 		int flags;
    738 
    739 		if (mp->mnt_flag & MNT_RDONLY)
    740 			flags = FREAD;
    741 		else
    742 			flags = FREAD|FWRITE;
    743 		vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY);
    744 		error = VOP_OPEN(devvp, flags, FSCRED);
    745 		VOP_UNLOCK(devvp);
    746 		if (error)
    747 			goto fail;
    748 		error = lfs_mountfs(devvp, mp, l);		/* LFS */
    749 		if (error) {
    750 			vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY);
    751 			(void)VOP_CLOSE(devvp, flags, NOCRED);
    752 			VOP_UNLOCK(devvp);
    753 			goto fail;
    754 		}
    755 
    756 		ump = VFSTOULFS(mp);
    757 		fs = ump->um_lfs;
    758 	} else {
    759 		/*
    760 		 * Update the mount.
    761 		 */
    762 
    763 		/*
    764 		 * The initial mount got a reference on this
    765 		 * device, so drop the one obtained via
    766 		 * namei(), above.
    767 		 */
    768 		vrele(devvp);
    769 
    770 		ump = VFSTOULFS(mp);
    771 		fs = ump->um_lfs;
    772 		if (fs->lfs_ronly && (mp->mnt_iflag & IMNT_WANTRDWR)) {
    773 			/*
    774 			 * Changing from read-only to read/write.
    775 			 * Note in the superblocks that we're writing.
    776 			 */
    777 			fs->lfs_ronly = 0;
    778 			if (fs->lfs_pflags & LFS_PF_CLEAN) {
    779 				fs->lfs_pflags &= ~LFS_PF_CLEAN;
    780 				lfs_writesuper(fs, fs->lfs_sboffs[0]);
    781 				lfs_writesuper(fs, fs->lfs_sboffs[1]);
    782 			}
    783 		}
    784 		if (args->fspec == NULL)
    785 			return EINVAL;
    786 	}
    787 
    788 	error = set_statvfs_info(path, UIO_USERSPACE, args->fspec,
    789 	    UIO_USERSPACE, mp->mnt_op->vfs_name, mp, l);
    790 	if (error == 0)
    791 		(void)strncpy(fs->lfs_fsmnt, mp->mnt_stat.f_mntonname,
    792 			      sizeof(fs->lfs_fsmnt));
    793 	return error;
    794 
    795 fail:
    796 	vrele(devvp);
    797 	return (error);
    798 }
    799 
    800 
    801 /*
    802  * Common code for mount and mountroot
    803  * LFS specific
    804  */
    805 int
    806 lfs_mountfs(struct vnode *devvp, struct mount *mp, struct lwp *l)
    807 {
    808 	struct dlfs *tdfs, *dfs, *adfs;
    809 	struct lfs *fs;
    810 	struct ulfsmount *ump;
    811 	struct vnode *vp;
    812 	struct buf *bp, *abp;
    813 	dev_t dev;
    814 	int error, i, ronly, fsbsize;
    815 	kauth_cred_t cred;
    816 	CLEANERINFO *cip;
    817 	SEGUSE *sup;
    818 	daddr_t sb_addr;
    819 
    820 	cred = l ? l->l_cred : NOCRED;
    821 
    822 	/*
    823 	 * Flush out any old buffers remaining from a previous use.
    824 	 */
    825 	vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY);
    826 	error = vinvalbuf(devvp, V_SAVE, cred, l, 0, 0);
    827 	VOP_UNLOCK(devvp);
    828 	if (error)
    829 		return (error);
    830 
    831 	ronly = (mp->mnt_flag & MNT_RDONLY) != 0;
    832 
    833 	/* Don't free random space on error. */
    834 	bp = NULL;
    835 	abp = NULL;
    836 	ump = NULL;
    837 
    838 	sb_addr = LFS_LABELPAD / DEV_BSIZE;
    839 	while (1) {
    840 		/* Read in the superblock. */
    841 		error = bread(devvp, sb_addr, LFS_SBPAD, cred, 0, &bp);
    842 		if (error)
    843 			goto out;
    844 		dfs = (struct dlfs *)bp->b_data;
    845 
    846 		/* Check the basics. */
    847 		if (dfs->dlfs_magic != LFS_MAGIC || dfs->dlfs_bsize > MAXBSIZE ||
    848 		    dfs->dlfs_version > LFS_VERSION ||
    849 		    dfs->dlfs_bsize < sizeof(struct dlfs)) {
    850 			DLOG((DLOG_MOUNT, "lfs_mountfs: primary superblock sanity failed\n"));
    851 			error = EINVAL;		/* XXX needs translation */
    852 			goto out;
    853 		}
    854 		if (dfs->dlfs_inodefmt > LFS_MAXINODEFMT) {
    855 			DLOG((DLOG_MOUNT, "lfs_mountfs: unknown inode format %d\n",
    856 			       dfs->dlfs_inodefmt));
    857 			error = EINVAL;
    858 			goto out;
    859 		}
    860 
    861 		if (dfs->dlfs_version == 1)
    862 			fsbsize = DEV_BSIZE;
    863 		else {
    864 			fsbsize = 1 << dfs->dlfs_ffshift;
    865 			/*
    866 			 * Could be, if the frag size is large enough, that we
    867 			 * don't have the "real" primary superblock.  If that's
    868 			 * the case, get the real one, and try again.
    869 			 */
    870 			if (sb_addr != (dfs->dlfs_sboffs[0] << (dfs->dlfs_ffshift - DEV_BSHIFT))) {
    871 				DLOG((DLOG_MOUNT, "lfs_mountfs: sb daddr"
    872 				      " 0x%llx is not right, trying 0x%llx\n",
    873 				      (long long)sb_addr,
    874 				      (long long)(dfs->dlfs_sboffs[0] << (dfs->dlfs_ffshift - DEV_BSHIFT))));
    875 				sb_addr = dfs->dlfs_sboffs[0] << (dfs->dlfs_ffshift - DEV_BSHIFT);
    876 				brelse(bp, 0);
    877 				continue;
    878 			}
    879 		}
    880 		break;
    881 	}
    882 
    883 	/*
    884 	 * Check the second superblock to see which is newer; then mount
    885 	 * using the older of the two.	This is necessary to ensure that
    886 	 * the filesystem is valid if it was not unmounted cleanly.
    887 	 */
    888 
    889 	if (dfs->dlfs_sboffs[1] &&
    890 	    dfs->dlfs_sboffs[1] - LFS_LABELPAD / fsbsize > LFS_SBPAD / fsbsize)
    891 	{
    892 		error = bread(devvp, dfs->dlfs_sboffs[1] * (fsbsize / DEV_BSIZE),
    893 			LFS_SBPAD, cred, 0, &abp);
    894 		if (error)
    895 			goto out;
    896 		adfs = (struct dlfs *)abp->b_data;
    897 
    898 		if (dfs->dlfs_version == 1) {
    899 			/* 1s resolution comparison */
    900 			if (adfs->dlfs_tstamp < dfs->dlfs_tstamp)
    901 				tdfs = adfs;
    902 			else
    903 				tdfs = dfs;
    904 		} else {
    905 			/* monotonic infinite-resolution comparison */
    906 			if (adfs->dlfs_serial < dfs->dlfs_serial)
    907 				tdfs = adfs;
    908 			else
    909 				tdfs = dfs;
    910 		}
    911 
    912 		/* Check the basics. */
    913 		if (tdfs->dlfs_magic != LFS_MAGIC ||
    914 		    tdfs->dlfs_bsize > MAXBSIZE ||
    915 		    tdfs->dlfs_version > LFS_VERSION ||
    916 		    tdfs->dlfs_bsize < sizeof(struct dlfs)) {
    917 			DLOG((DLOG_MOUNT, "lfs_mountfs: alt superblock"
    918 			      " sanity failed\n"));
    919 			error = EINVAL;		/* XXX needs translation */
    920 			goto out;
    921 		}
    922 	} else {
    923 		DLOG((DLOG_MOUNT, "lfs_mountfs: invalid alt superblock"
    924 		      " daddr=0x%x\n", dfs->dlfs_sboffs[1]));
    925 		error = EINVAL;
    926 		goto out;
    927 	}
    928 
    929 	/* Allocate the mount structure, copy the superblock into it. */
    930 	fs = kmem_zalloc(sizeof(struct lfs), KM_SLEEP);
    931 	memcpy(&fs->lfs_dlfs, tdfs, sizeof(struct dlfs));
    932 
    933 	/* Compatibility */
    934 	if (fs->lfs_version < 2) {
    935 		fs->lfs_sumsize = LFS_V1_SUMMARY_SIZE;
    936 		fs->lfs_ibsize = fs->lfs_bsize;
    937 		fs->lfs_start = fs->lfs_sboffs[0];
    938 		fs->lfs_tstamp = fs->lfs_otstamp;
    939 		fs->lfs_fsbtodb = 0;
    940 	}
    941 	if (fs->lfs_resvseg == 0)
    942 		fs->lfs_resvseg = MIN(fs->lfs_minfreeseg - 1, \
    943 			MAX(MIN_RESV_SEGS, fs->lfs_minfreeseg / 2 + 1));
    944 
    945 	/*
    946 	 * If we aren't going to be able to write meaningfully to this
    947 	 * filesystem, and were not mounted readonly, bomb out now.
    948 	 */
    949 	if (lfs_fsbtob(fs, LFS_NRESERVE(fs)) > LFS_MAX_BYTES && !ronly) {
    950 		DLOG((DLOG_MOUNT, "lfs_mount: to mount this filesystem read/write,"
    951 		      " we need BUFPAGES >= %lld\n",
    952 		      (long long)((bufmem_hiwater / bufmem_lowater) *
    953 				  LFS_INVERSE_MAX_BYTES(
    954 					  lfs_fsbtob(fs, LFS_NRESERVE(fs))) >> PAGE_SHIFT)));
    955 		kmem_free(fs, sizeof(struct lfs));
    956 		error = EFBIG; /* XXX needs translation */
    957 		goto out;
    958 	}
    959 
    960 	/* Before rolling forward, lock so vget will sleep for other procs */
    961 	if (l != NULL) {
    962 		fs->lfs_flags = LFS_NOTYET;
    963 		fs->lfs_rfpid = l->l_proc->p_pid;
    964 	}
    965 
    966 	ump = kmem_zalloc(sizeof(*ump), KM_SLEEP);
    967 	ump->um_lfs = fs;
    968 	ump->um_ops = &lfs_ulfsops;
    969 	ump->um_fstype = ULFS1;
    970 	if (sizeof(struct lfs) < LFS_SBPAD) {			/* XXX why? */
    971 		brelse(bp, BC_INVAL);
    972 		brelse(abp, BC_INVAL);
    973 	} else {
    974 		brelse(bp, 0);
    975 		brelse(abp, 0);
    976 	}
    977 	bp = NULL;
    978 	abp = NULL;
    979 
    980 
    981 	/* Set up the I/O information */
    982 	fs->lfs_devbsize = DEV_BSIZE;
    983 	fs->lfs_iocount = 0;
    984 	fs->lfs_diropwait = 0;
    985 	fs->lfs_activesb = 0;
    986 	fs->lfs_uinodes = 0;
    987 	fs->lfs_ravail = 0;
    988 	fs->lfs_favail = 0;
    989 	fs->lfs_sbactive = 0;
    990 
    991 	/* Set up the ifile and lock aflags */
    992 	fs->lfs_doifile = 0;
    993 	fs->lfs_writer = 0;
    994 	fs->lfs_dirops = 0;
    995 	fs->lfs_nadirop = 0;
    996 	fs->lfs_seglock = 0;
    997 	fs->lfs_pdflush = 0;
    998 	fs->lfs_sleepers = 0;
    999 	fs->lfs_pages = 0;
   1000 	rw_init(&fs->lfs_fraglock);
   1001 	rw_init(&fs->lfs_iflock);
   1002 	cv_init(&fs->lfs_stopcv, "lfsstop");
   1003 
   1004 	/* Set the file system readonly/modify bits. */
   1005 	fs->lfs_ronly = ronly;
   1006 	if (ronly == 0)
   1007 		fs->lfs_fmod = 1;
   1008 
   1009 	/* Initialize the mount structure. */
   1010 	dev = devvp->v_rdev;
   1011 	mp->mnt_data = ump;
   1012 	mp->mnt_stat.f_fsidx.__fsid_val[0] = (long)dev;
   1013 	mp->mnt_stat.f_fsidx.__fsid_val[1] = makefstype(MOUNT_LFS);
   1014 	mp->mnt_stat.f_fsid = mp->mnt_stat.f_fsidx.__fsid_val[0];
   1015 	mp->mnt_stat.f_namemax = LFS_MAXNAMLEN;
   1016 	mp->mnt_stat.f_iosize = fs->lfs_bsize;
   1017 	mp->mnt_flag |= MNT_LOCAL;
   1018 	mp->mnt_fs_bshift = fs->lfs_bshift;
   1019 	ump->um_flags = 0;
   1020 	ump->um_mountp = mp;
   1021 	ump->um_dev = dev;
   1022 	ump->um_devvp = devvp;
   1023 	ump->um_bptrtodb = fs->lfs_ffshift - DEV_BSHIFT;
   1024 	ump->um_seqinc = fs->lfs_frag;
   1025 	ump->um_nindir = fs->lfs_nindir;
   1026 	ump->um_lognindir = ffs(fs->lfs_nindir) - 1;
   1027 	for (i = 0; i < ULFS_MAXQUOTAS; i++)
   1028 		ump->um_quotas[i] = NULLVP;
   1029 	ump->um_maxsymlinklen = fs->lfs_maxsymlinklen;
   1030 	ump->um_dirblksiz = LFS_DIRBLKSIZ;
   1031 	ump->um_maxfilesize = fs->lfs_maxfilesize;
   1032 	if (ump->um_maxsymlinklen > 0)
   1033 		mp->mnt_iflag |= IMNT_DTYPE;
   1034 	devvp->v_specmountpoint = mp;
   1035 
   1036 	/* Set up reserved memory for pageout */
   1037 	lfs_setup_resblks(fs);
   1038 	/* Set up vdirop tailq */
   1039 	TAILQ_INIT(&fs->lfs_dchainhd);
   1040 	/* and paging tailq */
   1041 	TAILQ_INIT(&fs->lfs_pchainhd);
   1042 	/* and delayed segment accounting for truncation list */
   1043 	LIST_INIT(&fs->lfs_segdhd);
   1044 
   1045 	/*
   1046 	 * We use the ifile vnode for almost every operation.  Instead of
   1047 	 * retrieving it from the hash table each time we retrieve it here,
   1048 	 * artificially increment the reference count and keep a pointer
   1049 	 * to it in the incore copy of the superblock.
   1050 	 */
   1051 	if ((error = VFS_VGET(mp, LFS_IFILE_INUM, &vp)) != 0) {
   1052 		DLOG((DLOG_MOUNT, "lfs_mountfs: ifile vget failed, error=%d\n", error));
   1053 		goto out;
   1054 	}
   1055 	fs->lfs_ivnode = vp;
   1056 	vref(vp);
   1057 
   1058 	/* Set up inode bitmap and order free list */
   1059 	lfs_order_freelist(fs);
   1060 
   1061 	/* Set up segment usage flags for the autocleaner. */
   1062 	fs->lfs_nactive = 0;
   1063 	fs->lfs_suflags = (u_int32_t **)malloc(2 * sizeof(u_int32_t *),
   1064 						M_SEGMENT, M_WAITOK);
   1065 	fs->lfs_suflags[0] = (u_int32_t *)malloc(fs->lfs_nseg * sizeof(u_int32_t),
   1066 						 M_SEGMENT, M_WAITOK);
   1067 	fs->lfs_suflags[1] = (u_int32_t *)malloc(fs->lfs_nseg * sizeof(u_int32_t),
   1068 						 M_SEGMENT, M_WAITOK);
   1069 	memset(fs->lfs_suflags[1], 0, fs->lfs_nseg * sizeof(u_int32_t));
   1070 	for (i = 0; i < fs->lfs_nseg; i++) {
   1071 		int changed;
   1072 
   1073 		LFS_SEGENTRY(sup, fs, i, bp);
   1074 		changed = 0;
   1075 		if (!ronly) {
   1076 			if (sup->su_nbytes == 0 &&
   1077 			    !(sup->su_flags & SEGUSE_EMPTY)) {
   1078 				sup->su_flags |= SEGUSE_EMPTY;
   1079 				++changed;
   1080 			} else if (!(sup->su_nbytes == 0) &&
   1081 				   (sup->su_flags & SEGUSE_EMPTY)) {
   1082 				sup->su_flags &= ~SEGUSE_EMPTY;
   1083 				++changed;
   1084 			}
   1085 			if (sup->su_flags & (SEGUSE_ACTIVE|SEGUSE_INVAL)) {
   1086 				sup->su_flags &= ~(SEGUSE_ACTIVE|SEGUSE_INVAL);
   1087 				++changed;
   1088 			}
   1089 		}
   1090 		fs->lfs_suflags[0][i] = sup->su_flags;
   1091 		if (changed)
   1092 			LFS_WRITESEGENTRY(sup, fs, i, bp);
   1093 		else
   1094 			brelse(bp, 0);
   1095 	}
   1096 
   1097 #ifdef LFS_KERNEL_RFW
   1098 	lfs_roll_forward(fs, mp, l);
   1099 #endif
   1100 
   1101 	/* If writing, sb is not clean; record in case of immediate crash */
   1102 	if (!fs->lfs_ronly) {
   1103 		fs->lfs_pflags &= ~LFS_PF_CLEAN;
   1104 		lfs_writesuper(fs, fs->lfs_sboffs[0]);
   1105 		lfs_writesuper(fs, fs->lfs_sboffs[1]);
   1106 	}
   1107 
   1108 	/* Allow vget now that roll-forward is complete */
   1109 	fs->lfs_flags &= ~(LFS_NOTYET);
   1110 	wakeup(&fs->lfs_flags);
   1111 
   1112 	/*
   1113 	 * Initialize the ifile cleaner info with information from
   1114 	 * the superblock.
   1115 	 */
   1116 	LFS_CLEANERINFO(cip, fs, bp);
   1117 	cip->clean = fs->lfs_nclean;
   1118 	cip->dirty = fs->lfs_nseg - fs->lfs_nclean;
   1119 	cip->avail = fs->lfs_avail;
   1120 	cip->bfree = fs->lfs_bfree;
   1121 	(void) LFS_BWRITE_LOG(bp); /* Ifile */
   1122 
   1123 	/*
   1124 	 * Mark the current segment as ACTIVE, since we're going to
   1125 	 * be writing to it.
   1126 	 */
   1127 	LFS_SEGENTRY(sup, fs, lfs_dtosn(fs, fs->lfs_offset), bp);
   1128 	sup->su_flags |= SEGUSE_DIRTY | SEGUSE_ACTIVE;
   1129 	fs->lfs_nactive++;
   1130 	LFS_WRITESEGENTRY(sup, fs, lfs_dtosn(fs, fs->lfs_offset), bp);  /* Ifile */
   1131 
   1132 	/* Now that roll-forward is done, unlock the Ifile */
   1133 	vput(vp);
   1134 
   1135 	/* Start the pagedaemon-anticipating daemon */
   1136 	mutex_enter(&lfs_lock);
   1137 	if (lfs_writer_daemon == 0 && lfs_writer_lid == 0 &&
   1138 	    kthread_create(PRI_BIO, 0, NULL,
   1139 	    lfs_writerd, NULL, NULL, "lfs_writer") != 0)
   1140 		panic("fork lfs_writer");
   1141 	mutex_exit(&lfs_lock);
   1142 
   1143 	printf("WARNING: the log-structured file system is experimental\n"
   1144 	    "WARNING: it may cause system crashes and/or corrupt data\n");
   1145 
   1146 	return (0);
   1147 
   1148 out:
   1149 	if (bp)
   1150 		brelse(bp, 0);
   1151 	if (abp)
   1152 		brelse(abp, 0);
   1153 	if (ump) {
   1154 		kmem_free(ump->um_lfs, sizeof(struct lfs));
   1155 		kmem_free(ump, sizeof(*ump));
   1156 		mp->mnt_data = NULL;
   1157 	}
   1158 
   1159 	return (error);
   1160 }
   1161 
   1162 /*
   1163  * unmount system call
   1164  */
   1165 int
   1166 lfs_unmount(struct mount *mp, int mntflags)
   1167 {
   1168 	struct lwp *l = curlwp;
   1169 	struct ulfsmount *ump;
   1170 	struct lfs *fs;
   1171 	int error, flags, ronly;
   1172 	vnode_t *vp;
   1173 
   1174 	flags = 0;
   1175 	if (mntflags & MNT_FORCE)
   1176 		flags |= FORCECLOSE;
   1177 
   1178 	ump = VFSTOULFS(mp);
   1179 	fs = ump->um_lfs;
   1180 
   1181 	/* Two checkpoints */
   1182 	lfs_segwrite(mp, SEGM_CKP | SEGM_SYNC);
   1183 	lfs_segwrite(mp, SEGM_CKP | SEGM_SYNC);
   1184 
   1185 	/* wake up the cleaner so it can die */
   1186 	lfs_wakeup_cleaner(fs);
   1187 	mutex_enter(&lfs_lock);
   1188 	while (fs->lfs_sleepers)
   1189 		mtsleep(&fs->lfs_sleepers, PRIBIO + 1, "lfs_sleepers", 0,
   1190 			&lfs_lock);
   1191 	mutex_exit(&lfs_lock);
   1192 
   1193 #ifdef LFS_QUOTA
   1194         if ((error = lfsquota1_umount(mp, flags)) != 0)
   1195 		return (error);
   1196 #endif
   1197 	if ((error = vflush(mp, fs->lfs_ivnode, flags)) != 0)
   1198 		return (error);
   1199 	if ((error = VFS_SYNC(mp, 1, l->l_cred)) != 0)
   1200 		return (error);
   1201 	vp = fs->lfs_ivnode;
   1202 	mutex_enter(vp->v_interlock);
   1203 	if (LIST_FIRST(&vp->v_dirtyblkhd))
   1204 		panic("lfs_unmount: still dirty blocks on ifile vnode");
   1205 	mutex_exit(vp->v_interlock);
   1206 
   1207 	/* Explicitly write the superblock, to update serial and pflags */
   1208 	fs->lfs_pflags |= LFS_PF_CLEAN;
   1209 	lfs_writesuper(fs, fs->lfs_sboffs[0]);
   1210 	lfs_writesuper(fs, fs->lfs_sboffs[1]);
   1211 	mutex_enter(&lfs_lock);
   1212 	while (fs->lfs_iocount)
   1213 		mtsleep(&fs->lfs_iocount, PRIBIO + 1, "lfs_umount", 0,
   1214 			&lfs_lock);
   1215 	mutex_exit(&lfs_lock);
   1216 
   1217 	/* Finish with the Ifile, now that we're done with it */
   1218 	vgone(fs->lfs_ivnode);
   1219 
   1220 	ronly = !fs->lfs_ronly;
   1221 	if (ump->um_devvp->v_type != VBAD)
   1222 		ump->um_devvp->v_specmountpoint = NULL;
   1223 	vn_lock(ump->um_devvp, LK_EXCLUSIVE | LK_RETRY);
   1224 	error = VOP_CLOSE(ump->um_devvp,
   1225 	    ronly ? FREAD : FREAD|FWRITE, NOCRED);
   1226 	vput(ump->um_devvp);
   1227 
   1228 	/* Complain about page leakage */
   1229 	if (fs->lfs_pages > 0)
   1230 		printf("lfs_unmount: still claim %d pages (%d in subsystem)\n",
   1231 			fs->lfs_pages, lfs_subsys_pages);
   1232 
   1233 	/* Free per-mount data structures */
   1234 	free(fs->lfs_ino_bitmap, M_SEGMENT);
   1235 	free(fs->lfs_suflags[0], M_SEGMENT);
   1236 	free(fs->lfs_suflags[1], M_SEGMENT);
   1237 	free(fs->lfs_suflags, M_SEGMENT);
   1238 	lfs_free_resblks(fs);
   1239 	cv_destroy(&fs->lfs_stopcv);
   1240 	rw_destroy(&fs->lfs_fraglock);
   1241 	rw_destroy(&fs->lfs_iflock);
   1242 
   1243 	kmem_free(fs, sizeof(struct lfs));
   1244 	kmem_free(ump, sizeof(*ump));
   1245 
   1246 	mp->mnt_data = NULL;
   1247 	mp->mnt_flag &= ~MNT_LOCAL;
   1248 	return (error);
   1249 }
   1250 
   1251 /*
   1252  * Get file system statistics.
   1253  *
   1254  * NB: We don't lock to access the superblock here, because it's not
   1255  * really that important if we get it wrong.
   1256  */
   1257 int
   1258 lfs_statvfs(struct mount *mp, struct statvfs *sbp)
   1259 {
   1260 	struct lfs *fs;
   1261 	struct ulfsmount *ump;
   1262 
   1263 	ump = VFSTOULFS(mp);
   1264 	fs = ump->um_lfs;
   1265 	if (fs->lfs_magic != LFS_MAGIC)
   1266 		panic("lfs_statvfs: magic");
   1267 
   1268 	sbp->f_bsize = fs->lfs_bsize;
   1269 	sbp->f_frsize = fs->lfs_fsize;
   1270 	sbp->f_iosize = fs->lfs_bsize;
   1271 	sbp->f_blocks = LFS_EST_NONMETA(fs) - VTOI(fs->lfs_ivnode)->i_lfs_effnblks;
   1272 
   1273 	sbp->f_bfree = LFS_EST_BFREE(fs);
   1274 	KASSERT(sbp->f_bfree <= fs->lfs_dsize);
   1275 #if 0
   1276 	if (sbp->f_bfree < 0)
   1277 		sbp->f_bfree = 0;
   1278 #endif
   1279 
   1280 	sbp->f_bresvd = LFS_EST_RSVD(fs);
   1281 	if (sbp->f_bfree > sbp->f_bresvd)
   1282 		sbp->f_bavail = sbp->f_bfree - sbp->f_bresvd;
   1283 	else
   1284 		sbp->f_bavail = 0;
   1285 
   1286 	sbp->f_files = fs->lfs_bfree / lfs_btofsb(fs, fs->lfs_ibsize)
   1287 	    * LFS_INOPB(fs);
   1288 	sbp->f_ffree = sbp->f_files - fs->lfs_nfiles;
   1289 	sbp->f_favail = sbp->f_ffree;
   1290 	sbp->f_fresvd = 0;
   1291 	copy_statvfs_info(sbp, mp);
   1292 	return (0);
   1293 }
   1294 
   1295 /*
   1296  * Go through the disk queues to initiate sandbagged IO;
   1297  * go through the inodes to write those that have been modified;
   1298  * initiate the writing of the super block if it has been modified.
   1299  *
   1300  * Note: we are always called with the filesystem marked `MPBUSY'.
   1301  */
   1302 int
   1303 lfs_sync(struct mount *mp, int waitfor, kauth_cred_t cred)
   1304 {
   1305 	int error;
   1306 	struct lfs *fs;
   1307 
   1308 	fs = VFSTOULFS(mp)->um_lfs;
   1309 	if (fs->lfs_ronly)
   1310 		return 0;
   1311 
   1312 	/* Snapshots should not hose the syncer */
   1313 	/*
   1314 	 * XXX Sync can block here anyway, since we don't have a very
   1315 	 * XXX good idea of how much data is pending.  If it's more
   1316 	 * XXX than a segment and lfs_nextseg is close to the end of
   1317 	 * XXX the log, we'll likely block.
   1318 	 */
   1319 	mutex_enter(&lfs_lock);
   1320 	if (fs->lfs_nowrap && fs->lfs_nextseg < fs->lfs_curseg) {
   1321 		mutex_exit(&lfs_lock);
   1322 		return 0;
   1323 	}
   1324 	mutex_exit(&lfs_lock);
   1325 
   1326 	lfs_writer_enter(fs, "lfs_dirops");
   1327 
   1328 	/* All syncs must be checkpoints until roll-forward is implemented. */
   1329 	DLOG((DLOG_FLUSH, "lfs_sync at 0x%x\n", fs->lfs_offset));
   1330 	error = lfs_segwrite(mp, SEGM_CKP | (waitfor ? SEGM_SYNC : 0));
   1331 	lfs_writer_leave(fs);
   1332 #ifdef LFS_QUOTA
   1333 	lfs_qsync(mp);
   1334 #endif
   1335 	return (error);
   1336 }
   1337 
   1338 /*
   1339  * Look up an LFS dinode number to find its incore vnode.  If not already
   1340  * in core, read it in from the specified device.  Return the inode locked.
   1341  * Detection and handling of mount points must be done by the calling routine.
   1342  */
   1343 int
   1344 lfs_vget(struct mount *mp, ino_t ino, struct vnode **vpp)
   1345 {
   1346 	struct lfs *fs;
   1347 	struct ulfs1_dinode *dip;
   1348 	struct inode *ip;
   1349 	struct buf *bp;
   1350 	struct ifile *ifp;
   1351 	struct vnode *vp;
   1352 	struct ulfsmount *ump;
   1353 	daddr_t daddr;
   1354 	dev_t dev;
   1355 	int error, retries;
   1356 	struct timespec ts;
   1357 
   1358 	memset(&ts, 0, sizeof ts);	/* XXX gcc */
   1359 
   1360 	ump = VFSTOULFS(mp);
   1361 	dev = ump->um_dev;
   1362 	fs = ump->um_lfs;
   1363 
   1364 	/*
   1365 	 * If the filesystem is not completely mounted yet, suspend
   1366 	 * any access requests (wait for roll-forward to complete).
   1367 	 */
   1368 	mutex_enter(&lfs_lock);
   1369 	while ((fs->lfs_flags & LFS_NOTYET) && curproc->p_pid != fs->lfs_rfpid)
   1370 		mtsleep(&fs->lfs_flags, PRIBIO+1, "lfs_notyet", 0,
   1371 			&lfs_lock);
   1372 	mutex_exit(&lfs_lock);
   1373 
   1374 retry:
   1375 	if ((*vpp = ulfs_ihashget(dev, ino, LK_EXCLUSIVE)) != NULL)
   1376 		return (0);
   1377 
   1378 	error = getnewvnode(VT_LFS, mp, lfs_vnodeop_p, NULL, &vp);
   1379 	if (error) {
   1380 		*vpp = NULL;
   1381 		 return (error);
   1382 	}
   1383 
   1384 	mutex_enter(&ulfs_hashlock);
   1385 	if (ulfs_ihashget(dev, ino, 0) != NULL) {
   1386 		mutex_exit(&ulfs_hashlock);
   1387 		ungetnewvnode(vp);
   1388 		goto retry;
   1389 	}
   1390 
   1391 	/* Translate the inode number to a disk address. */
   1392 	if (ino == LFS_IFILE_INUM)
   1393 		daddr = fs->lfs_idaddr;
   1394 	else {
   1395 		/* XXX bounds-check this too */
   1396 		LFS_IENTRY(ifp, fs, ino, bp);
   1397 		daddr = ifp->if_daddr;
   1398 		if (fs->lfs_version > 1) {
   1399 			ts.tv_sec = ifp->if_atime_sec;
   1400 			ts.tv_nsec = ifp->if_atime_nsec;
   1401 		}
   1402 
   1403 		brelse(bp, 0);
   1404 		if (daddr == LFS_UNUSED_DADDR) {
   1405 			*vpp = NULLVP;
   1406 			mutex_exit(&ulfs_hashlock);
   1407 			ungetnewvnode(vp);
   1408 			return (ENOENT);
   1409 		}
   1410 	}
   1411 
   1412 	/* Allocate/init new vnode/inode. */
   1413 	lfs_vcreate(mp, ino, vp);
   1414 
   1415 	/*
   1416 	 * Put it onto its hash chain and lock it so that other requests for
   1417 	 * this inode will block if they arrive while we are sleeping waiting
   1418 	 * for old data structures to be purged or for the contents of the
   1419 	 * disk portion of this inode to be read.
   1420 	 */
   1421 	ip = VTOI(vp);
   1422 	ulfs_ihashins(ip);
   1423 	mutex_exit(&ulfs_hashlock);
   1424 
   1425 	/*
   1426 	 * XXX
   1427 	 * This may not need to be here, logically it should go down with
   1428 	 * the i_devvp initialization.
   1429 	 * Ask Kirk.
   1430 	 */
   1431 	ip->i_lfs = ump->um_lfs;
   1432 
   1433 	/* Read in the disk contents for the inode, copy into the inode. */
   1434 	retries = 0;
   1435     again:
   1436 	error = bread(ump->um_devvp, LFS_FSBTODB(fs, daddr),
   1437 		(fs->lfs_version == 1 ? fs->lfs_bsize : fs->lfs_ibsize),
   1438 		NOCRED, 0, &bp);
   1439 	if (error) {
   1440 		/*
   1441 		 * The inode does not contain anything useful, so it would
   1442 		 * be misleading to leave it on its hash chain. With mode
   1443 		 * still zero, it will be unlinked and returned to the free
   1444 		 * list by vput().
   1445 		 */
   1446 		vput(vp);
   1447 		*vpp = NULL;
   1448 		return (error);
   1449 	}
   1450 
   1451 	dip = lfs_ifind(fs, ino, bp);
   1452 	if (dip == NULL) {
   1453 		/* Assume write has not completed yet; try again */
   1454 		brelse(bp, BC_INVAL);
   1455 		++retries;
   1456 		if (retries > LFS_IFIND_RETRIES) {
   1457 #ifdef DEBUG
   1458 			/* If the seglock is held look at the bpp to see
   1459 			   what is there anyway */
   1460 			mutex_enter(&lfs_lock);
   1461 			if (fs->lfs_seglock > 0) {
   1462 				struct buf **bpp;
   1463 				struct ulfs1_dinode *dp;
   1464 				int i;
   1465 
   1466 				for (bpp = fs->lfs_sp->bpp;
   1467 				     bpp != fs->lfs_sp->cbpp; ++bpp) {
   1468 					if ((*bpp)->b_vp == fs->lfs_ivnode &&
   1469 					    bpp != fs->lfs_sp->bpp) {
   1470 						/* Inode block */
   1471 						printf("lfs_vget: block 0x%" PRIx64 ": ",
   1472 						       (*bpp)->b_blkno);
   1473 						dp = (struct ulfs1_dinode *)(*bpp)->b_data;
   1474 						for (i = 0; i < LFS_INOPB(fs); i++)
   1475 							if (dp[i].di_inumber)
   1476 								printf("%d ", dp[i].di_inumber);
   1477 						printf("\n");
   1478 					}
   1479 				}
   1480 			}
   1481 			mutex_exit(&lfs_lock);
   1482 #endif /* DEBUG */
   1483 			panic("lfs_vget: dinode not found");
   1484 		}
   1485 		mutex_enter(&lfs_lock);
   1486 		if (fs->lfs_iocount) {
   1487 			DLOG((DLOG_VNODE, "lfs_vget: dinode %d not found, retrying...\n", ino));
   1488 			(void)mtsleep(&fs->lfs_iocount, PRIBIO + 1,
   1489 				      "lfs ifind", 1, &lfs_lock);
   1490 		} else
   1491 			retries = LFS_IFIND_RETRIES;
   1492 		mutex_exit(&lfs_lock);
   1493 		goto again;
   1494 	}
   1495 	*ip->i_din.ffs1_din = *dip;
   1496 	brelse(bp, 0);
   1497 
   1498 	if (fs->lfs_version > 1) {
   1499 		ip->i_ffs1_atime = ts.tv_sec;
   1500 		ip->i_ffs1_atimensec = ts.tv_nsec;
   1501 	}
   1502 
   1503 	lfs_vinit(mp, &vp);
   1504 
   1505 	*vpp = vp;
   1506 
   1507 	KASSERT(VOP_ISLOCKED(vp));
   1508 
   1509 	return (0);
   1510 }
   1511 
   1512 /*
   1513  * File handle to vnode
   1514  */
   1515 int
   1516 lfs_fhtovp(struct mount *mp, struct fid *fhp, struct vnode **vpp)
   1517 {
   1518 	struct lfid lfh;
   1519 	struct buf *bp;
   1520 	IFILE *ifp;
   1521 	int32_t daddr;
   1522 	struct lfs *fs;
   1523 	vnode_t *vp;
   1524 
   1525 	if (fhp->fid_len != sizeof(struct lfid))
   1526 		return EINVAL;
   1527 
   1528 	memcpy(&lfh, fhp, sizeof(lfh));
   1529 	if (lfh.lfid_ino < LFS_IFILE_INUM)
   1530 		return ESTALE;
   1531 
   1532 	fs = VFSTOULFS(mp)->um_lfs;
   1533 	if (lfh.lfid_ident != fs->lfs_ident)
   1534 		return ESTALE;
   1535 
   1536 	if (lfh.lfid_ino >
   1537 	    ((VTOI(fs->lfs_ivnode)->i_ffs1_size >> fs->lfs_bshift) -
   1538 	     fs->lfs_cleansz - fs->lfs_segtabsz) * fs->lfs_ifpb)
   1539 		return ESTALE;
   1540 
   1541 	mutex_enter(&ulfs_ihash_lock);
   1542 	vp = ulfs_ihashlookup(VFSTOULFS(mp)->um_dev, lfh.lfid_ino);
   1543 	mutex_exit(&ulfs_ihash_lock);
   1544 	if (vp == NULL) {
   1545 		LFS_IENTRY(ifp, fs, lfh.lfid_ino, bp);
   1546 		daddr = ifp->if_daddr;
   1547 		brelse(bp, 0);
   1548 		if (daddr == LFS_UNUSED_DADDR)
   1549 			return ESTALE;
   1550 	}
   1551 
   1552 	return (ulfs_fhtovp(mp, &lfh.lfid_ufid, vpp));
   1553 }
   1554 
   1555 /*
   1556  * Vnode pointer to File handle
   1557  */
   1558 /* ARGSUSED */
   1559 int
   1560 lfs_vptofh(struct vnode *vp, struct fid *fhp, size_t *fh_size)
   1561 {
   1562 	struct inode *ip;
   1563 	struct lfid lfh;
   1564 
   1565 	if (*fh_size < sizeof(struct lfid)) {
   1566 		*fh_size = sizeof(struct lfid);
   1567 		return E2BIG;
   1568 	}
   1569 	*fh_size = sizeof(struct lfid);
   1570 	ip = VTOI(vp);
   1571 	memset(&lfh, 0, sizeof(lfh));
   1572 	lfh.lfid_len = sizeof(struct lfid);
   1573 	lfh.lfid_ino = ip->i_number;
   1574 	lfh.lfid_gen = ip->i_gen;
   1575 	lfh.lfid_ident = ip->i_lfs->lfs_ident;
   1576 	memcpy(fhp, &lfh, sizeof(lfh));
   1577 	return (0);
   1578 }
   1579 
   1580 /*
   1581  * ulfs_bmaparray callback function for writing.
   1582  *
   1583  * Since blocks will be written to the new segment anyway,
   1584  * we don't care about current daddr of them.
   1585  */
   1586 static bool
   1587 lfs_issequential_hole(const struct ulfsmount *ump,
   1588     daddr_t daddr0, daddr_t daddr1)
   1589 {
   1590 	daddr0 = (daddr_t)((int32_t)daddr0); /* XXX ondisk32 */
   1591 	daddr1 = (daddr_t)((int32_t)daddr1); /* XXX ondisk32 */
   1592 
   1593 	KASSERT(daddr0 == UNWRITTEN ||
   1594 	    (0 <= daddr0 && daddr0 <= LFS_MAX_DADDR));
   1595 	KASSERT(daddr1 == UNWRITTEN ||
   1596 	    (0 <= daddr1 && daddr1 <= LFS_MAX_DADDR));
   1597 
   1598 	/* NOTE: all we want to know here is 'hole or not'. */
   1599 	/* NOTE: UNASSIGNED is converted to 0 by ulfs_bmaparray. */
   1600 
   1601 	/*
   1602 	 * treat UNWRITTENs and all resident blocks as 'contiguous'
   1603 	 */
   1604 	if (daddr0 != 0 && daddr1 != 0)
   1605 		return true;
   1606 
   1607 	/*
   1608 	 * both are in hole?
   1609 	 */
   1610 	if (daddr0 == 0 && daddr1 == 0)
   1611 		return true; /* all holes are 'contiguous' for us. */
   1612 
   1613 	return false;
   1614 }
   1615 
   1616 /*
   1617  * lfs_gop_write functions exactly like genfs_gop_write, except that
   1618  * (1) it requires the seglock to be held by its caller, and sp->fip
   1619  *     to be properly initialized (it will return without re-initializing
   1620  *     sp->fip, and without calling lfs_writeseg).
   1621  * (2) it uses the remaining space in the segment, rather than VOP_BMAP,
   1622  *     to determine how large a block it can write at once (though it does
   1623  *     still use VOP_BMAP to find holes in the file);
   1624  * (3) it calls lfs_gatherblock instead of VOP_STRATEGY on its blocks
   1625  *     (leaving lfs_writeseg to deal with the cluster blocks, so we might
   1626  *     now have clusters of clusters, ick.)
   1627  */
   1628 static int
   1629 lfs_gop_write(struct vnode *vp, struct vm_page **pgs, int npages,
   1630     int flags)
   1631 {
   1632 	int i, error, run, haveeof = 0;
   1633 	int fs_bshift;
   1634 	vaddr_t kva;
   1635 	off_t eof, offset, startoffset = 0;
   1636 	size_t bytes, iobytes, skipbytes;
   1637 	bool async = (flags & PGO_SYNCIO) == 0;
   1638 	daddr_t lbn, blkno;
   1639 	struct vm_page *pg;
   1640 	struct buf *mbp, *bp;
   1641 	struct vnode *devvp = VTOI(vp)->i_devvp;
   1642 	struct inode *ip = VTOI(vp);
   1643 	struct lfs *fs = ip->i_lfs;
   1644 	struct segment *sp = fs->lfs_sp;
   1645 	UVMHIST_FUNC("lfs_gop_write"); UVMHIST_CALLED(ubchist);
   1646 	const char * failreason = NULL;
   1647 
   1648 	ASSERT_SEGLOCK(fs);
   1649 
   1650 	/* The Ifile lives in the buffer cache */
   1651 	KASSERT(vp != fs->lfs_ivnode);
   1652 
   1653 	/*
   1654 	 * We don't want to fill the disk before the cleaner has a chance
   1655 	 * to make room for us.  If we're in danger of doing that, fail
   1656 	 * with EAGAIN.  The caller will have to notice this, unlock
   1657 	 * so the cleaner can run, relock and try again.
   1658 	 *
   1659 	 * We must write everything, however, if our vnode is being
   1660 	 * reclaimed.
   1661 	 */
   1662 	if (LFS_STARVED_FOR_SEGS(fs) && !(vp->v_iflag & VI_XLOCK)) {
   1663 		failreason = "Starved for segs and not flushing vp";
   1664  		goto tryagain;
   1665 	}
   1666 
   1667 	/*
   1668 	 * Sometimes things slip past the filters in lfs_putpages,
   1669 	 * and the pagedaemon tries to write pages---problem is
   1670 	 * that the pagedaemon never acquires the segment lock.
   1671 	 *
   1672 	 * Alternatively, pages that were clean when we called
   1673 	 * genfs_putpages may have become dirty in the meantime.  In this
   1674 	 * case the segment header is not properly set up for blocks
   1675 	 * to be added to it.
   1676 	 *
   1677 	 * Unbusy and unclean the pages, and put them on the ACTIVE
   1678 	 * queue under the hypothesis that they couldn't have got here
   1679 	 * unless they were modified *quite* recently.
   1680 	 *
   1681 	 * XXXUBC that last statement is an oversimplification of course.
   1682 	 */
   1683 	if (!LFS_SEGLOCK_HELD(fs)) {
   1684 		failreason = "Seglock not held";
   1685 		goto tryagain;
   1686 	}
   1687 	if (ip->i_lfs_iflags & LFSI_NO_GOP_WRITE) {
   1688 		failreason = "Inode with no_gop_write";
   1689 		goto tryagain;
   1690 	}
   1691 	if ((pgs[0]->offset & fs->lfs_bmask) != 0) {
   1692 		failreason = "Bad page offset";
   1693 		goto tryagain;
   1694 	}
   1695 
   1696 	UVMHIST_LOG(ubchist, "vp %p pgs %p npages %d flags 0x%x",
   1697 	    vp, pgs, npages, flags);
   1698 
   1699 	GOP_SIZE(vp, vp->v_size, &eof, 0);
   1700 	haveeof = 1;
   1701 
   1702 	if (vp->v_type == VREG)
   1703 		fs_bshift = vp->v_mount->mnt_fs_bshift;
   1704 	else
   1705 		fs_bshift = DEV_BSHIFT;
   1706 	error = 0;
   1707 	pg = pgs[0];
   1708 	startoffset = pg->offset;
   1709 	KASSERT(eof >= 0);
   1710 
   1711 	if (startoffset >= eof) {
   1712 		failreason = "Offset beyond EOF";
   1713 		goto tryagain;
   1714 	} else
   1715 		bytes = MIN(npages << PAGE_SHIFT, eof - startoffset);
   1716 	skipbytes = 0;
   1717 
   1718 	KASSERT(bytes != 0);
   1719 
   1720 	/* Swap PG_DELWRI for PG_PAGEOUT */
   1721 	for (i = 0; i < npages; i++) {
   1722 		if (pgs[i]->flags & PG_DELWRI) {
   1723 			KASSERT(!(pgs[i]->flags & PG_PAGEOUT));
   1724 			pgs[i]->flags &= ~PG_DELWRI;
   1725 			pgs[i]->flags |= PG_PAGEOUT;
   1726 			uvm_pageout_start(1);
   1727 			mutex_enter(vp->v_interlock);
   1728 			mutex_enter(&uvm_pageqlock);
   1729 			uvm_pageunwire(pgs[i]);
   1730 			mutex_exit(&uvm_pageqlock);
   1731 			mutex_exit(vp->v_interlock);
   1732 		}
   1733 	}
   1734 
   1735 	/*
   1736 	 * Check to make sure we're starting on a block boundary.
   1737 	 * We'll check later to make sure we always write entire
   1738 	 * blocks (or fragments).
   1739 	 */
   1740 	if (startoffset & fs->lfs_bmask)
   1741 		printf("%" PRId64 " & %" PRId64 " = %" PRId64 "\n",
   1742 		       startoffset, fs->lfs_bmask,
   1743 		       startoffset & fs->lfs_bmask);
   1744 	KASSERT((startoffset & fs->lfs_bmask) == 0);
   1745 	if (bytes & fs->lfs_ffmask) {
   1746 		printf("lfs_gop_write: asked to write %ld bytes\n", (long)bytes);
   1747 		panic("lfs_gop_write: non-integer blocks");
   1748 	}
   1749 
   1750 	/*
   1751 	 * We could deadlock here on pager_map with UVMPAGER_MAPIN_WAITOK.
   1752 	 * If we would, write what we have and try again.  If we don't
   1753 	 * have anything to write, we'll have to sleep.
   1754 	 */
   1755 	if ((kva = uvm_pagermapin(pgs, npages, UVMPAGER_MAPIN_WRITE |
   1756 				      (((SEGSUM *)(sp->segsum))->ss_nfinfo < 1 ?
   1757 				       UVMPAGER_MAPIN_WAITOK : 0))) == 0x0) {
   1758 		DLOG((DLOG_PAGE, "lfs_gop_write: forcing write\n"));
   1759 #if 0
   1760 		      " with nfinfo=%d at offset 0x%x\n",
   1761 		      (int)((SEGSUM *)(sp->segsum))->ss_nfinfo,
   1762 		      (unsigned)fs->lfs_offset));
   1763 #endif
   1764 		lfs_updatemeta(sp);
   1765 		lfs_release_finfo(fs);
   1766 		(void) lfs_writeseg(fs, sp);
   1767 
   1768 		lfs_acquire_finfo(fs, ip->i_number, ip->i_gen);
   1769 
   1770 		/*
   1771 		 * Having given up all of the pager_map we were holding,
   1772 		 * we can now wait for aiodoned to reclaim it for us
   1773 		 * without fear of deadlock.
   1774 		 */
   1775 		kva = uvm_pagermapin(pgs, npages, UVMPAGER_MAPIN_WRITE |
   1776 				     UVMPAGER_MAPIN_WAITOK);
   1777 	}
   1778 
   1779 	mbp = getiobuf(NULL, true);
   1780 	UVMHIST_LOG(ubchist, "vp %p mbp %p num now %d bytes 0x%x",
   1781 	    vp, mbp, vp->v_numoutput, bytes);
   1782 	mbp->b_bufsize = npages << PAGE_SHIFT;
   1783 	mbp->b_data = (void *)kva;
   1784 	mbp->b_resid = mbp->b_bcount = bytes;
   1785 	mbp->b_cflags = BC_BUSY|BC_AGE;
   1786 	mbp->b_iodone = uvm_aio_biodone;
   1787 
   1788 	bp = NULL;
   1789 	for (offset = startoffset;
   1790 	    bytes > 0;
   1791 	    offset += iobytes, bytes -= iobytes) {
   1792 		lbn = offset >> fs_bshift;
   1793 		error = ulfs_bmaparray(vp, lbn, &blkno, NULL, NULL, &run,
   1794 		    lfs_issequential_hole);
   1795 		if (error) {
   1796 			UVMHIST_LOG(ubchist, "ulfs_bmaparray() -> %d",
   1797 			    error,0,0,0);
   1798 			skipbytes += bytes;
   1799 			bytes = 0;
   1800 			break;
   1801 		}
   1802 
   1803 		iobytes = MIN((((off_t)lbn + 1 + run) << fs_bshift) - offset,
   1804 		    bytes);
   1805 		if (blkno == (daddr_t)-1) {
   1806 			skipbytes += iobytes;
   1807 			continue;
   1808 		}
   1809 
   1810 		/*
   1811 		 * Discover how much we can really pack into this buffer.
   1812 		 */
   1813 		/* If no room in the current segment, finish it up */
   1814 		if (sp->sum_bytes_left < sizeof(int32_t) ||
   1815 		    sp->seg_bytes_left < (1 << fs->lfs_bshift)) {
   1816 			int vers;
   1817 
   1818 			lfs_updatemeta(sp);
   1819 			vers = sp->fip->fi_version;
   1820 			lfs_release_finfo(fs);
   1821 			(void) lfs_writeseg(fs, sp);
   1822 
   1823 			lfs_acquire_finfo(fs, ip->i_number, vers);
   1824 		}
   1825 		/* Check both for space in segment and space in segsum */
   1826 		iobytes = MIN(iobytes, (sp->seg_bytes_left >> fs_bshift)
   1827 					<< fs_bshift);
   1828 		iobytes = MIN(iobytes, (sp->sum_bytes_left / sizeof(int32_t))
   1829 				       << fs_bshift);
   1830 		KASSERT(iobytes > 0);
   1831 
   1832 		/* if it's really one i/o, don't make a second buf */
   1833 		if (offset == startoffset && iobytes == bytes) {
   1834 			bp = mbp;
   1835 			/*
   1836 			 * All the LFS output is done by the segwriter.  It
   1837 			 * will increment numoutput by one for all the bufs it
   1838 			 * recieves.  However this buffer needs one extra to
   1839 			 * account for aiodone.
   1840 			 */
   1841 			mutex_enter(vp->v_interlock);
   1842 			vp->v_numoutput++;
   1843 			mutex_exit(vp->v_interlock);
   1844 		} else {
   1845 			bp = getiobuf(NULL, true);
   1846 			UVMHIST_LOG(ubchist, "vp %p bp %p num now %d",
   1847 			    vp, bp, vp->v_numoutput, 0);
   1848 			nestiobuf_setup(mbp, bp, offset - pg->offset, iobytes);
   1849 			/*
   1850 			 * LFS doesn't like async I/O here, dies with
   1851 			 * an assert in lfs_bwrite().  Is that assert
   1852 			 * valid?  I retained non-async behaviour when
   1853 			 * converted this to use nestiobuf --pooka
   1854 			 */
   1855 			bp->b_flags &= ~B_ASYNC;
   1856 		}
   1857 
   1858 		/* XXX This is silly ... is this necessary? */
   1859 		mutex_enter(&bufcache_lock);
   1860 		mutex_enter(vp->v_interlock);
   1861 		bgetvp(vp, bp);
   1862 		mutex_exit(vp->v_interlock);
   1863 		mutex_exit(&bufcache_lock);
   1864 
   1865 		bp->b_lblkno = lfs_lblkno(fs, offset);
   1866 		bp->b_private = mbp;
   1867 		if (devvp->v_type == VBLK) {
   1868 			bp->b_dev = devvp->v_rdev;
   1869 		}
   1870 		VOP_BWRITE(bp->b_vp, bp);
   1871 		while (lfs_gatherblock(sp, bp, NULL))
   1872 			continue;
   1873 	}
   1874 
   1875 	nestiobuf_done(mbp, skipbytes, error);
   1876 	if (skipbytes) {
   1877 		UVMHIST_LOG(ubchist, "skipbytes %d", skipbytes, 0,0,0);
   1878 	}
   1879 	UVMHIST_LOG(ubchist, "returning 0", 0,0,0,0);
   1880 
   1881 	if (!async) {
   1882 		/* Start a segment write. */
   1883 		UVMHIST_LOG(ubchist, "flushing", 0,0,0,0);
   1884 		mutex_enter(&lfs_lock);
   1885 		lfs_flush(fs, 0, 1);
   1886 		mutex_exit(&lfs_lock);
   1887 	}
   1888 
   1889 	if ((sp->seg_flags & SEGM_SINGLE) && fs->lfs_curseg != fs->lfs_startseg)
   1890 		return EAGAIN;
   1891 
   1892 	return (0);
   1893 
   1894     tryagain:
   1895 	/*
   1896 	 * We can't write the pages, for whatever reason.
   1897 	 * Clean up after ourselves, and make the caller try again.
   1898 	 */
   1899 	mutex_enter(vp->v_interlock);
   1900 
   1901 	/* Tell why we're here, if we know */
   1902 	if (failreason != NULL) {
   1903 		DLOG((DLOG_PAGE, "lfs_gop_write: %s\n", failreason));
   1904 	}
   1905 	if (haveeof && startoffset >= eof) {
   1906  		DLOG((DLOG_PAGE, "lfs_gop_write: ino %d start 0x%" PRIx64
   1907  		      " eof 0x%" PRIx64 " npages=%d\n", VTOI(vp)->i_number,
   1908  		      pgs[0]->offset, eof, npages));
   1909 	}
   1910 
   1911 	mutex_enter(&uvm_pageqlock);
   1912 	for (i = 0; i < npages; i++) {
   1913 		pg = pgs[i];
   1914 
   1915 		if (pg->flags & PG_PAGEOUT)
   1916 			uvm_pageout_done(1);
   1917 		if (pg->flags & PG_DELWRI) {
   1918 			uvm_pageunwire(pg);
   1919 		}
   1920 		uvm_pageactivate(pg);
   1921 		pg->flags &= ~(PG_CLEAN|PG_DELWRI|PG_PAGEOUT|PG_RELEASED);
   1922 		DLOG((DLOG_PAGE, "pg[%d] = %p (vp %p off %" PRIx64 ")\n", i, pg,
   1923 			vp, pg->offset));
   1924 		DLOG((DLOG_PAGE, "pg[%d]->flags = %x\n", i, pg->flags));
   1925 		DLOG((DLOG_PAGE, "pg[%d]->pqflags = %x\n", i, pg->pqflags));
   1926 		DLOG((DLOG_PAGE, "pg[%d]->uanon = %p\n", i, pg->uanon));
   1927 		DLOG((DLOG_PAGE, "pg[%d]->uobject = %p\n", i, pg->uobject));
   1928 		DLOG((DLOG_PAGE, "pg[%d]->wire_count = %d\n", i,
   1929 		      pg->wire_count));
   1930 		DLOG((DLOG_PAGE, "pg[%d]->loan_count = %d\n", i,
   1931 		      pg->loan_count));
   1932 	}
   1933 	/* uvm_pageunbusy takes care of PG_BUSY, PG_WANTED */
   1934 	uvm_page_unbusy(pgs, npages);
   1935 	mutex_exit(&uvm_pageqlock);
   1936 	mutex_exit(vp->v_interlock);
   1937 	return EAGAIN;
   1938 }
   1939 
   1940 /*
   1941  * finish vnode/inode initialization.
   1942  * used by lfs_vget and lfs_fastvget.
   1943  */
   1944 void
   1945 lfs_vinit(struct mount *mp, struct vnode **vpp)
   1946 {
   1947 	struct vnode *vp = *vpp;
   1948 	struct inode *ip = VTOI(vp);
   1949 	struct ulfsmount *ump = VFSTOULFS(mp);
   1950 	struct lfs *fs = ump->um_lfs;
   1951 	int i;
   1952 
   1953 	ip->i_mode = ip->i_ffs1_mode;
   1954 	ip->i_nlink = ip->i_ffs1_nlink;
   1955 	ip->i_lfs_osize = ip->i_size = ip->i_ffs1_size;
   1956 	ip->i_flags = ip->i_ffs1_flags;
   1957 	ip->i_gen = ip->i_ffs1_gen;
   1958 	ip->i_uid = ip->i_ffs1_uid;
   1959 	ip->i_gid = ip->i_ffs1_gid;
   1960 
   1961 	ip->i_lfs_effnblks = ip->i_ffs1_blocks;
   1962 	ip->i_lfs_odnlink = ip->i_ffs1_nlink;
   1963 
   1964 	/*
   1965 	 * Initialize the vnode from the inode, check for aliases.  In all
   1966 	 * cases re-init ip, the underlying vnode/inode may have changed.
   1967 	 */
   1968 	ulfs_vinit(mp, lfs_specop_p, lfs_fifoop_p, &vp);
   1969 	ip = VTOI(vp);
   1970 
   1971 	memset(ip->i_lfs_fragsize, 0, ULFS_NDADDR * sizeof(*ip->i_lfs_fragsize));
   1972 	if (vp->v_type != VLNK || ip->i_size >= ip->i_ump->um_maxsymlinklen) {
   1973 #ifdef DEBUG
   1974 		for (i = (ip->i_size + fs->lfs_bsize - 1) >> fs->lfs_bshift;
   1975 		    i < ULFS_NDADDR; i++) {
   1976 			if ((vp->v_type == VBLK || vp->v_type == VCHR) &&
   1977 			    i == 0)
   1978 				continue;
   1979 			if (ip->i_ffs1_db[i] != 0) {
   1980 				lfs_dump_dinode(ip->i_din.ffs1_din);
   1981 				panic("inconsistent inode (direct)");
   1982 			}
   1983 		}
   1984 		for ( ; i < ULFS_NDADDR + ULFS_NIADDR; i++) {
   1985 			if (ip->i_ffs1_ib[i - ULFS_NDADDR] != 0) {
   1986 				lfs_dump_dinode(ip->i_din.ffs1_din);
   1987 				panic("inconsistent inode (indirect)");
   1988 			}
   1989 		}
   1990 #endif /* DEBUG */
   1991 		for (i = 0; i < ULFS_NDADDR; i++)
   1992 			if (ip->i_ffs1_db[i] != 0)
   1993 				ip->i_lfs_fragsize[i] = lfs_blksize(fs, ip, i);
   1994 	}
   1995 
   1996 #ifdef DIAGNOSTIC
   1997 	if (vp->v_type == VNON) {
   1998 # ifdef DEBUG
   1999 		lfs_dump_dinode(ip->i_din.ffs1_din);
   2000 # endif
   2001 		panic("lfs_vinit: ino %llu is type VNON! (ifmt=%o)\n",
   2002 		      (unsigned long long)ip->i_number,
   2003 		      (ip->i_mode & LFS_IFMT) >> 12);
   2004 	}
   2005 #endif /* DIAGNOSTIC */
   2006 
   2007 	/*
   2008 	 * Finish inode initialization now that aliasing has been resolved.
   2009 	 */
   2010 
   2011 	ip->i_devvp = ump->um_devvp;
   2012 	vref(ip->i_devvp);
   2013 	genfs_node_init(vp, &lfs_genfsops);
   2014 	uvm_vnp_setsize(vp, ip->i_size);
   2015 
   2016 	/* Initialize hiblk from file size */
   2017 	ip->i_lfs_hiblk = lfs_lblkno(ip->i_lfs, ip->i_size + ip->i_lfs->lfs_bsize - 1) - 1;
   2018 
   2019 	*vpp = vp;
   2020 }
   2021 
   2022 /*
   2023  * Resize the filesystem to contain the specified number of segments.
   2024  */
   2025 int
   2026 lfs_resize_fs(struct lfs *fs, int newnsegs)
   2027 {
   2028 	SEGUSE *sup;
   2029 	struct buf *bp, *obp;
   2030 	daddr_t olast, nlast, ilast, noff, start, end;
   2031 	struct vnode *ivp;
   2032 	struct inode *ip;
   2033 	int error, badnews, inc, oldnsegs;
   2034 	int sbbytes, csbbytes, gain, cgain;
   2035 	int i;
   2036 
   2037 	/* Only support v2 and up */
   2038 	if (fs->lfs_version < 2)
   2039 		return EOPNOTSUPP;
   2040 
   2041 	/* If we're doing nothing, do it fast */
   2042 	oldnsegs = fs->lfs_nseg;
   2043 	if (newnsegs == oldnsegs)
   2044 		return 0;
   2045 
   2046 	/* We always have to have two superblocks */
   2047 	if (newnsegs <= lfs_dtosn(fs, fs->lfs_sboffs[1]))
   2048 		return EFBIG;
   2049 
   2050 	ivp = fs->lfs_ivnode;
   2051 	ip = VTOI(ivp);
   2052 	error = 0;
   2053 
   2054 	/* Take the segment lock so no one else calls lfs_newseg() */
   2055 	lfs_seglock(fs, SEGM_PROT);
   2056 
   2057 	/*
   2058 	 * Make sure the segments we're going to be losing, if any,
   2059 	 * are in fact empty.  We hold the seglock, so their status
   2060 	 * cannot change underneath us.  Count the superblocks we lose,
   2061 	 * while we're at it.
   2062 	 */
   2063 	sbbytes = csbbytes = 0;
   2064 	cgain = 0;
   2065 	for (i = newnsegs; i < oldnsegs; i++) {
   2066 		LFS_SEGENTRY(sup, fs, i, bp);
   2067 		badnews = sup->su_nbytes || !(sup->su_flags & SEGUSE_INVAL);
   2068 		if (sup->su_flags & SEGUSE_SUPERBLOCK)
   2069 			sbbytes += LFS_SBPAD;
   2070 		if (!(sup->su_flags & SEGUSE_DIRTY)) {
   2071 			++cgain;
   2072 			if (sup->su_flags & SEGUSE_SUPERBLOCK)
   2073 				csbbytes += LFS_SBPAD;
   2074 		}
   2075 		brelse(bp, 0);
   2076 		if (badnews) {
   2077 			error = EBUSY;
   2078 			goto out;
   2079 		}
   2080 	}
   2081 
   2082 	/* Note old and new segment table endpoints, and old ifile size */
   2083 	olast = fs->lfs_cleansz + fs->lfs_segtabsz;
   2084 	nlast = howmany(newnsegs, fs->lfs_sepb) + fs->lfs_cleansz;
   2085 	ilast = ivp->v_size >> fs->lfs_bshift;
   2086 	noff = nlast - olast;
   2087 
   2088 	/*
   2089 	 * Make sure no one can use the Ifile while we change it around.
   2090 	 * Even after taking the iflock we need to make sure no one still
   2091 	 * is holding Ifile buffers, so we get each one, to drain them.
   2092 	 * (XXX this could be done better.)
   2093 	 */
   2094 	rw_enter(&fs->lfs_iflock, RW_WRITER);
   2095 	for (i = 0; i < ilast; i++) {
   2096 		/* XXX what to do if bread fails? */
   2097 		bread(ivp, i, fs->lfs_bsize, NOCRED, 0, &bp);
   2098 		brelse(bp, 0);
   2099 	}
   2100 
   2101 	/* Allocate new Ifile blocks */
   2102 	for (i = ilast; i < ilast + noff; i++) {
   2103 		if (lfs_balloc(ivp, i * fs->lfs_bsize, fs->lfs_bsize, NOCRED, 0,
   2104 			       &bp) != 0)
   2105 			panic("balloc extending ifile");
   2106 		memset(bp->b_data, 0, fs->lfs_bsize);
   2107 		VOP_BWRITE(bp->b_vp, bp);
   2108 	}
   2109 
   2110 	/* Register new ifile size */
   2111 	ip->i_size += noff * fs->lfs_bsize;
   2112 	ip->i_ffs1_size = ip->i_size;
   2113 	uvm_vnp_setsize(ivp, ip->i_size);
   2114 
   2115 	/* Copy the inode table to its new position */
   2116 	if (noff != 0) {
   2117 		if (noff < 0) {
   2118 			start = nlast;
   2119 			end = ilast + noff;
   2120 			inc = 1;
   2121 		} else {
   2122 			start = ilast + noff - 1;
   2123 			end = nlast - 1;
   2124 			inc = -1;
   2125 		}
   2126 		for (i = start; i != end; i += inc) {
   2127 			if (bread(ivp, i, fs->lfs_bsize, NOCRED,
   2128 			    B_MODIFY, &bp) != 0)
   2129 				panic("resize: bread dst blk failed");
   2130 			if (bread(ivp, i - noff, fs->lfs_bsize,
   2131 			    NOCRED, 0, &obp))
   2132 				panic("resize: bread src blk failed");
   2133 			memcpy(bp->b_data, obp->b_data, fs->lfs_bsize);
   2134 			VOP_BWRITE(bp->b_vp, bp);
   2135 			brelse(obp, 0);
   2136 		}
   2137 	}
   2138 
   2139 	/* If we are expanding, write the new empty SEGUSE entries */
   2140 	if (newnsegs > oldnsegs) {
   2141 		for (i = oldnsegs; i < newnsegs; i++) {
   2142 			if ((error = bread(ivp, i / fs->lfs_sepb +
   2143 					   fs->lfs_cleansz, fs->lfs_bsize,
   2144 					   NOCRED, B_MODIFY, &bp)) != 0)
   2145 				panic("lfs: ifile read: %d", error);
   2146 			while ((i + 1) % fs->lfs_sepb && i < newnsegs) {
   2147 				sup = &((SEGUSE *)bp->b_data)[i % fs->lfs_sepb];
   2148 				memset(sup, 0, sizeof(*sup));
   2149 				i++;
   2150 			}
   2151 			VOP_BWRITE(bp->b_vp, bp);
   2152 		}
   2153 	}
   2154 
   2155 	/* Zero out unused superblock offsets */
   2156 	for (i = 2; i < LFS_MAXNUMSB; i++)
   2157 		if (lfs_dtosn(fs, fs->lfs_sboffs[i]) >= newnsegs)
   2158 			fs->lfs_sboffs[i] = 0x0;
   2159 
   2160 	/*
   2161 	 * Correct superblock entries that depend on fs size.
   2162 	 * The computations of these are as follows:
   2163 	 *
   2164 	 * size  = lfs_segtod(fs, nseg)
   2165 	 * dsize = lfs_segtod(fs, nseg - minfreeseg) - lfs_btofsb(#super * LFS_SBPAD)
   2166 	 * bfree = dsize - lfs_btofsb(fs, bsize * nseg / 2) - blocks_actually_used
   2167 	 * avail = lfs_segtod(fs, nclean) - lfs_btofsb(#clean_super * LFS_SBPAD)
   2168 	 *         + (lfs_segtod(fs, 1) - (offset - curseg))
   2169 	 *	   - lfs_segtod(fs, minfreeseg - (minfreeseg / 2))
   2170 	 *
   2171 	 * XXX - we should probably adjust minfreeseg as well.
   2172 	 */
   2173 	gain = (newnsegs - oldnsegs);
   2174 	fs->lfs_nseg = newnsegs;
   2175 	fs->lfs_segtabsz = nlast - fs->lfs_cleansz;
   2176 	fs->lfs_size += gain * lfs_btofsb(fs, fs->lfs_ssize);
   2177 	fs->lfs_dsize += gain * lfs_btofsb(fs, fs->lfs_ssize) - lfs_btofsb(fs, sbbytes);
   2178 	fs->lfs_bfree += gain * lfs_btofsb(fs, fs->lfs_ssize) - lfs_btofsb(fs, sbbytes)
   2179 		       - gain * lfs_btofsb(fs, fs->lfs_bsize / 2);
   2180 	if (gain > 0) {
   2181 		fs->lfs_nclean += gain;
   2182 		fs->lfs_avail += gain * lfs_btofsb(fs, fs->lfs_ssize);
   2183 	} else {
   2184 		fs->lfs_nclean -= cgain;
   2185 		fs->lfs_avail -= cgain * lfs_btofsb(fs, fs->lfs_ssize) -
   2186 				 lfs_btofsb(fs, csbbytes);
   2187 	}
   2188 
   2189 	/* Resize segment flag cache */
   2190 	fs->lfs_suflags[0] = realloc(fs->lfs_suflags[0],
   2191 	    fs->lfs_nseg * sizeof(u_int32_t), M_SEGMENT, M_WAITOK);
   2192 	fs->lfs_suflags[1] = realloc(fs->lfs_suflags[1],
   2193 	    fs->lfs_nseg * sizeof(u_int32_t), M_SEGMENT, M_WAITOK);
   2194 	for (i = oldnsegs; i < newnsegs; i++)
   2195 		fs->lfs_suflags[0][i] = fs->lfs_suflags[1][i] = 0x0;
   2196 
   2197 	/* Truncate Ifile if necessary */
   2198 	if (noff < 0)
   2199 		lfs_truncate(ivp, ivp->v_size + (noff << fs->lfs_bshift), 0,
   2200 		    NOCRED);
   2201 
   2202 	/* Update cleaner info so the cleaner can die */
   2203 	/* XXX what to do if bread fails? */
   2204 	bread(ivp, 0, fs->lfs_bsize, NOCRED, B_MODIFY, &bp);
   2205 	((CLEANERINFO *)bp->b_data)->clean = fs->lfs_nclean;
   2206 	((CLEANERINFO *)bp->b_data)->dirty = fs->lfs_nseg - fs->lfs_nclean;
   2207 	VOP_BWRITE(bp->b_vp, bp);
   2208 
   2209 	/* Let Ifile accesses proceed */
   2210 	rw_exit(&fs->lfs_iflock);
   2211 
   2212     out:
   2213 	lfs_segunlock(fs);
   2214 	return error;
   2215 }
   2216