BSD 4.4 Lite Kernel Sources

1 files changed, 359 insertions, 0 deletions

diff --git a/sys/ufs/lfs/lfs_inode.c b/sys/ufs/lfs/lfs_inode.c
new file mode 100644
index 0000000..1a06aa2
--- /dev/null
+++ b/sys/ufs/lfs/lfs_inode.c
@@ -0,0 +1,359 @@
+/*
+ * Copyright (c) 1986, 1989, 1991, 1993
+ *	The Regents of the University of California.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *	@(#)lfs_inode.c	8.5 (Berkeley) 12/30/93
+ */
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/mount.h>
+#include <sys/proc.h>
+#include <sys/file.h>
+#include <sys/buf.h>
+#include <sys/vnode.h>
+#include <sys/kernel.h>
+#include <sys/malloc.h>
+
+#include <vm/vm.h>
+
+#include <ufs/ufs/quota.h>
+#include <ufs/ufs/inode.h>
+#include <ufs/ufs/ufsmount.h>
+#include <ufs/ufs/ufs_extern.h>
+
+#include <ufs/lfs/lfs.h>
+#include <ufs/lfs/lfs_extern.h>
+
+int
+lfs_init()
+{
+	return (ufs_init());
+}
+
+/* Search a block for a specific dinode. */
+struct dinode *
+lfs_ifind(fs, ino, dip)
+	struct lfs *fs;
+	ino_t ino;
+	register struct dinode *dip;
+{
+	register int cnt;
+	register struct dinode *ldip;
+
+	for (cnt = INOPB(fs), ldip = dip + (cnt - 1); cnt--; --ldip)
+		if (ldip->di_inumber == ino)
+			return (ldip);
+
+	panic("lfs_ifind: dinode %u not found", ino);
+	/* NOTREACHED */
+}
+
+int
+lfs_update(ap)
+	struct vop_update_args /* {
+		struct vnode *a_vp;
+		struct timeval *a_access;
+		struct timeval *a_modify;
+		int a_waitfor;
+	} */ *ap;
+{
+	struct vnode *vp = ap->a_vp;
+	struct inode *ip;
+
+	if (vp->v_mount->mnt_flag & MNT_RDONLY)
+		return (0);
+	ip = VTOI(vp);
+	if ((ip->i_flag &
+	    (IN_ACCESS | IN_CHANGE | IN_MODIFIED | IN_UPDATE)) == 0)
+		return (0);
+	if (ip->i_flag & IN_ACCESS)
+		ip->i_atime.ts_sec = ap->a_access->tv_sec;
+	if (ip->i_flag & IN_UPDATE) {
+		ip->i_mtime.ts_sec = ap->a_modify->tv_sec;
+		(ip)->i_modrev++;
+	}
+	if (ip->i_flag & IN_CHANGE)
+		ip->i_ctime.ts_sec = time.tv_sec;
+	ip->i_flag &= ~(IN_ACCESS | IN_CHANGE | IN_UPDATE);
+
+	if (!(ip->i_flag & IN_MODIFIED))
+		++(VFSTOUFS(vp->v_mount)->um_lfs->lfs_uinodes);
+	ip->i_flag |= IN_MODIFIED;
+
+	/* If sync, push back the vnode and any dirty blocks it may have. */
+	return (ap->a_waitfor & LFS_SYNC ? lfs_vflush(vp) : 0);
+}
+
+/* Update segment usage information when removing a block. */
+#define UPDATE_SEGUSE \
+	if (lastseg != -1) { \
+		LFS_SEGENTRY(sup, fs, lastseg, sup_bp); \
+		if ((num << fs->lfs_bshift) > sup->su_nbytes) \
+			panic("lfs_truncate: negative bytes in segment %d\n", \
+			    lastseg); \
+		sup->su_nbytes -= num << fs->lfs_bshift; \
+		e1 = VOP_BWRITE(sup_bp); \
+		blocksreleased += num; \
+	}
+
+#define SEGDEC { \
+	if (daddr != 0) { \
+		if (lastseg != (seg = datosn(fs, daddr))) { \
+			UPDATE_SEGUSE; \
+			num = 1; \
+			lastseg = seg; \
+		} else \
+			++num; \
+	} \
+}
+
+/*
+ * Truncate the inode ip to at most length size.  Update segment usage
+ * table information.
+ */
+/* ARGSUSED */
+int
+lfs_truncate(ap)
+	struct vop_truncate_args /* {
+		struct vnode *a_vp;
+		off_t a_length;
+		int a_flags;
+		struct ucred *a_cred;
+		struct proc *a_p;
+	} */ *ap;
+{
+	register struct indir *inp;
+	register int i;
+	register daddr_t *daddrp;
+	register struct vnode *vp = ap->a_vp;
+	off_t length = ap->a_length;
+	struct buf *bp, *sup_bp;
+	struct timeval tv;
+	struct ifile *ifp;
+	struct inode *ip;
+	struct lfs *fs;
+	struct indir a[NIADDR + 2], a_end[NIADDR + 2];
+	SEGUSE *sup;
+	daddr_t daddr, lastblock, lbn, olastblock;
+	long off, a_released, blocksreleased, i_released;
+	int e1, e2, depth, lastseg, num, offset, seg, size;
+
+	ip = VTOI(vp);
+	tv = time;
+	if (vp->v_type == VLNK && vp->v_mount->mnt_maxsymlinklen > 0) {
+#ifdef DIAGNOSTIC
+		if (length != 0)
+			panic("lfs_truncate: partial truncate of symlink");
+#endif
+		bzero((char *)&ip->i_shortlink, (u_int)ip->i_size);
+		ip->i_size = 0;
+		ip->i_flag |= IN_CHANGE | IN_UPDATE;
+		return (VOP_UPDATE(vp, &tv, &tv, 0));
+	}
+	vnode_pager_setsize(vp, (u_long)length);
+
+	fs = ip->i_lfs;
+
+	/* If length is larger than the file, just update the times. */
+	if (ip->i_size <= length) {
+		ip->i_flag |= IN_CHANGE | IN_UPDATE;
+		return (VOP_UPDATE(vp, &tv, &tv, 0));
+	}
+
+	/*
+	 * Calculate index into inode's block list of last direct and indirect
+	 * blocks (if any) which we want to keep.  Lastblock is 0 when the
+	 * file is truncated to 0.
+	 */
+	lastblock = lblkno(fs, length + fs->lfs_bsize - 1);
+	olastblock = lblkno(fs, ip->i_size + fs->lfs_bsize - 1) - 1;
+
+	/*
+	 * Update the size of the file. If the file is not being truncated to
+	 * a block boundry, the contents of the partial block following the end
+	 * of the file must be zero'ed in case it ever become accessable again
+	 * because of subsequent file growth.
+	 */
+	offset = blkoff(fs, length);
+	if (offset == 0)
+		ip->i_size = length;
+	else {
+		lbn = lblkno(fs, length);
+#ifdef QUOTA
+		if (e1 = getinoquota(ip))
+			return (e1);
+#endif	
+		if (e1 = bread(vp, lbn, fs->lfs_bsize, NOCRED, &bp))
+			return (e1);
+		ip->i_size = length;
+		size = blksize(fs);
+		(void)vnode_pager_uncache(vp);
+		bzero((char *)bp->b_data + offset, (u_int)(size - offset));
+		allocbuf(bp, size);
+		if (e1 = VOP_BWRITE(bp))
+			return (e1);
+	}
+	/*
+	 * Modify sup->su_nbyte counters for each deleted block; keep track
+	 * of number of blocks removed for ip->i_blocks.
+	 */
+	blocksreleased = 0;
+	num = 0;
+	lastseg = -1;
+
+	for (lbn = olastblock; lbn >= lastblock;) {
+		/* XXX use run length from bmap array to make this faster */
+		ufs_bmaparray(vp, lbn, &daddr, a, &depth, NULL);
+		if (lbn == olastblock)
+			for (i = NIADDR + 2; i--;)
+				a_end[i] = a[i];
+		switch (depth) {
+		case 0:				/* Direct block. */
+			daddr = ip->i_db[lbn];
+			SEGDEC;
+			ip->i_db[lbn] = 0;
+			--lbn;
+			break;
+#ifdef DIAGNOSTIC
+		case 1:				/* An indirect block. */
+			panic("lfs_truncate: ufs_bmaparray returned depth 1");
+			/* NOTREACHED */
+#endif
+		default:			/* Chain of indirect blocks. */
+			inp = a + --depth;
+			if (inp->in_off > 0 && lbn != lastblock) {
+				lbn -= inp->in_off < lbn - lastblock ?
+				    inp->in_off : lbn - lastblock;
+				break;
+			}
+			for (; depth && (inp->in_off == 0 || lbn == lastblock);
+			    --inp, --depth) {
+				if (bread(vp,
+				    inp->in_lbn, fs->lfs_bsize, NOCRED, &bp))
+					panic("lfs_truncate: bread bno %d",
+					    inp->in_lbn);
+				daddrp = (daddr_t *)bp->b_data + inp->in_off;
+				for (i = inp->in_off;
+				    i++ <= a_end[depth].in_off;) {
+					daddr = *daddrp++;
+					SEGDEC;
+				}
+				a_end[depth].in_off = NINDIR(fs) - 1;
+				if (inp->in_off == 0)
+					brelse (bp);
+				else {
+					bzero((daddr_t *)bp->b_data +
+					    inp->in_off, fs->lfs_bsize - 
+					    inp->in_off * sizeof(daddr_t));
+					if (e1 = VOP_BWRITE(bp)) 
+						return (e1);
+				}
+			}
+			if (depth == 0 && a[1].in_off == 0) {
+				off = a[0].in_off;
+				daddr = ip->i_ib[off];
+				SEGDEC;
+				ip->i_ib[off] = 0;
+			}
+			if (lbn == lastblock || lbn <= NDADDR)
+				--lbn;
+			else {
+				lbn -= NINDIR(fs);
+				if (lbn < lastblock)
+					lbn = lastblock;
+			}
+		}
+	}
+	UPDATE_SEGUSE;
+
+	/* If truncating the file to 0, update the version number. */
+	if (length == 0) {
+		LFS_IENTRY(ifp, fs, ip->i_number, bp);
+		++ifp->if_version;
+		(void) VOP_BWRITE(bp);
+	}
+
+#ifdef DIAGNOSTIC
+	if (ip->i_blocks < fsbtodb(fs, blocksreleased)) {
+		printf("lfs_truncate: block count < 0\n");
+		blocksreleased = ip->i_blocks;
+	}
+#endif
+	ip->i_blocks -= fsbtodb(fs, blocksreleased);
+	fs->lfs_bfree +=  fsbtodb(fs, blocksreleased);
+	ip->i_flag |= IN_CHANGE | IN_UPDATE;
+	/*
+	 * Traverse dirty block list counting number of dirty buffers
+	 * that are being deleted out of the cache, so that the lfs_avail
+	 * field can be updated.
+	 */
+	a_released = 0;
+	i_released = 0;
+	for (bp = vp->v_dirtyblkhd.lh_first; bp; bp = bp->b_vnbufs.le_next)
+		if (bp->b_flags & B_LOCKED) {
+			++a_released;
+			/*
+			 * XXX
+			 * When buffers are created in the cache, their block
+			 * number is set equal to their logical block number.
+			 * If that is still true, we are assuming that the
+			 * blocks are new (not yet on disk) and weren't
+			 * counted above.  However, there is a slight chance
+			 * that a block's disk address is equal to its logical
+			 * block number in which case, we'll get an overcounting
+			 * here.
+			 */
+			if (bp->b_blkno == bp->b_lblkno)
+				++i_released;
+		}
+	blocksreleased = fsbtodb(fs, i_released);
+#ifdef DIAGNOSTIC
+	if (blocksreleased > ip->i_blocks) {
+		printf("lfs_inode: Warning! %s\n",
+		    "more blocks released from inode than are in inode");
+		blocksreleased = ip->i_blocks;
+	}
+#endif
+	fs->lfs_bfree += blocksreleased;
+	ip->i_blocks -= blocksreleased;
+#ifdef DIAGNOSTIC
+	if (length == 0 && ip->i_blocks != 0)
+		printf("lfs_inode: Warning! %s%d%s\n",
+		    "Truncation to zero, but ", ip->i_blocks,
+		    " blocks left on inode");
+#endif
+	fs->lfs_avail += fsbtodb(fs, a_released);
+	e1 = vinvalbuf(vp, (length > 0) ? V_SAVE : 0, ap->a_cred, ap->a_p,
+	    0, 0); 
+	e2 = VOP_UPDATE(vp, &tv, &tv, 0);
+	return (e1 ? e1 : e2 ? e2 : 0);
+}