Teach fsck about snapshot files. These changes should have no

effect on operation of fsck on filesystems without snapshots.
If you get compilation errors, be sure that you have copies of
/usr/include/sys/mount.h (1.94), /usr/include/sys/stat.h (1.21),
and /usr/include/ufs/ffs/fs.h (1.16) as of July 4, 2000 or later.

sbin/fsck/dir.c

@@ -241,7 +241,7 @@ dircheck(idesc, dp)
 	if (dp->d_reclen == 0 ||
 	    dp->d_reclen > spaceleft ||
 	    (dp->d_reclen & 0x3) != 0)
-		return (0);
+		goto bad;
 	if (dp->d_ino == 0)
 		return (1);
 	size = DIRSIZ(!newinofmt, dp);
@@ -261,13 +261,19 @@ dircheck(idesc, dp)
 	    idesc->id_filesize < size ||
 	    namlen > MAXNAMLEN ||
 	    type > 15)
-		return (0);
+		goto bad;
 	for (cp = dp->d_name, size = 0; size < namlen; size++)
 		if (*cp == '\0' || (*cp++ == '/'))
-			return (0);
+			goto bad;
 	if (*cp != '\0')
-		return (0);
+		goto bad;
 	return (1);
+bad:
+	if (debug)
+		printf("Bad dir: ino %d reclen %d namlen %d type %d name %s\n",
+		    dp->d_ino, dp->d_reclen, dp->d_namlen, dp->d_type,
+		    dp->d_name);
+	return (0);
 }
 
 void

sbin/fsck/fsck.h

@@ -114,12 +114,14 @@ struct bufarea *pbp;		/* current inode block */
 #define	cgrp		(*cgblk.b_un.b_cg)
 
 enum fixstate {DONTKNOW, NOFIX, FIX, IGNORE};
+ino_t cursnapshot;
 
 struct inodesc {
 	enum fixstate id_fix;	/* policy on fixing errors */
 	int (*id_func)();	/* function to be applied to blocks of inode */
 	ino_t id_number;	/* inode number described */
 	ino_t id_parent;	/* for DATA nodes, their parent */
+	int id_lbn;		/* logical block number of current block */
 	ufs_daddr_t id_blkno;	/* current block number being examined */
 	int id_numfrags;	/* number of frags contained in block */
 	quad_t id_filesize;	/* for DATA nodes, the size of the directory */
@@ -130,8 +132,9 @@ struct inodesc {
 	char id_type;		/* type of descriptor, DATA or ADDR */
 };
 /* file types */
-#define	DATA	1
+#define	DATA	1	/* a directory */
-#define	ADDR	2
+#define	SNAP	2	/* a snapshot */
+#define	ADDR	3	/* anything but a directory or a snapshot */
 
 /*
  * Linked list of duplicate blocks.

sbin/fsck/inode.c

@@ -71,6 +71,7 @@ ckinode(dp, idesc)
 
 	if (idesc->id_fix != IGNORE)
 		idesc->id_fix = DONTKNOW;
+	idesc->id_lbn = -1;
 	idesc->id_entryno = 0;
 	idesc->id_filesize = dp->di_size;
 	mode = dp->di_mode & IFMT;
@@ -80,6 +81,7 @@ ckinode(dp, idesc)
 	dino = *dp;
 	ndb = howmany(dino.di_size, sblock.fs_bsize);
 	for (ap = &dino.di_db[0]; ap < &dino.di_db[NDADDR]; ap++) {
+		idesc->id_lbn++;
 		if (--ndb == 0 && (offset = blkoff(&sblock, dino.di_size)) != 0)
 			idesc->id_numfrags =
 				numfrags(&sblock, fragroundup(&sblock, offset));
@@ -106,7 +108,7 @@ ckinode(dp, idesc)
 			continue;
 		}
 		idesc->id_blkno = *ap;
-		if (idesc->id_type == ADDR)
+		if (idesc->id_type != DATA)
 			ret = (*idesc->id_func)(idesc);
 		else
 			ret = dirscan(idesc);
@@ -117,12 +119,14 @@ ckinode(dp, idesc)
 	remsize = dino.di_size - sblock.fs_bsize * NDADDR;
 	sizepb = sblock.fs_bsize;
 	for (ap = &dino.di_ib[0], n = 1; n <= NIADDR; ap++, n++) {
+		sizepb *= NINDIR(&sblock);
 		if (*ap) {
 			idesc->id_blkno = *ap;
 			ret = iblock(idesc, n, remsize);
 			if (ret & STOP)
 				return (ret);
 		} else {
+			idesc->id_lbn += sizepb / sblock.fs_bsize;
 			if (idesc->id_type == DATA && remsize > 0) {
 				/* An empty block in a directory XXX */
 				getpathname(pathbuf, idesc->id_number,
@@ -141,7 +145,6 @@ ckinode(dp, idesc)
                         	}
 			}
 		}
-		sizepb *= NINDIR(&sblock);
 		remsize -= sizepb;
 	}
 	return (KEEPON);
@@ -162,7 +165,7 @@ iblock(idesc, ilevel, isize)
 	char pathbuf[MAXPATHLEN + 1];
 	struct dinode *dp;
 
-	if (idesc->id_type == ADDR) {
+	if (idesc->id_type != DATA) {
 		func = idesc->id_func;
 		if (((n = (*func)(idesc)) & KEEPON) == 0)
 			return (n);
@@ -193,6 +196,8 @@ iblock(idesc, ilevel, isize)
 	}
 	aplim = &bp->b_un.b_indir[nif];
 	for (ap = bp->b_un.b_indir; ap < aplim; ap++) {
+		if (ilevel == 0)
+			idesc->id_lbn++;
 		if (*ap) {
 			idesc->id_blkno = *ap;
 			if (ilevel == 0)

sbin/fsck/pass1.c

@@ -40,6 +40,7 @@ static const char rcsid[] =
 #endif /* not lint */
 
 #include <sys/param.h>
+#include <sys/stat.h>
 
 #include <ufs/ufs/dinode.h>
 #include <ufs/ufs/dir.h>
@@ -82,7 +83,6 @@ pass1()
 	 * Find all allocated blocks.
 	 */
 	memset(&idesc, 0, sizeof(struct inodesc));
-	idesc.id_type = ADDR;
 	idesc.id_func = pass1check;
 	n_files = n_blks = 0;
 	for (c = 0; c < sblock.fs_ncg; c++) {
@@ -306,6 +306,10 @@ checkinode(inumber, idesc)
 	}
 	badblk = dupblk = 0;
 	idesc->id_number = inumber;
+	if (dp->di_flags & SF_SNAPSHOT)
+		idesc->id_type = SNAP;
+	else
+		idesc->id_type = ADDR;
 	(void)ckinode(dp, idesc);
 	idesc->id_entryno *= btodb(sblock.fs_fsize);
 	if (dp->di_blocks != idesc->id_entryno) {
@@ -341,6 +345,21 @@ pass1check(idesc)
 	register struct dups *dlp;
 	struct dups *new;
 
+	if (idesc->id_type == SNAP) {
+		if (blkno == BLK_NOCOPY)
+			return (KEEPON);
+		if (idesc->id_number == cursnapshot) {
+			if (blkno == blkstofrags(&sblock, idesc->id_lbn))
+				return (KEEPON);
+			if (blkno == BLK_SNAP) {
+				blkno = blkstofrags(&sblock, idesc->id_lbn);
+				idesc->id_entryno -= idesc->id_numfrags;
+			}
+		} else {
+			if (blkno == BLK_SNAP)
+				return (KEEPON);
+		}
+	}
 	if ((anyout = chkrange(blkno, idesc->id_numfrags)) != 0) {
 		blkerror(idesc->id_number, "BAD", blkno);
 		if (badblk++ >= MAXBAD) {

sbin/fsck/pass5.c

@@ -53,12 +53,12 @@ void
 pass5()
 {
 	int c, blk, frags, basesize, sumsize, mapsize, savednrpos = 0;
-	int inomapsize, blkmapsize;
+	int inomapsize, blkmapsize, astart, aend, ustart, uend;
 	struct fs *fs = &sblock;
 	struct cg *cg = &cgrp;
 	ufs_daddr_t dbase, dmax;
 	ufs_daddr_t d;
-	long i, j, k;
+	long i, j, k, l, m, n;
 	struct csum *cs;
 	struct csum cstotal;
 	struct inodesc idesc[3];
@@ -314,6 +314,72 @@ pass5()
 			       &cg_blktot(newcg)[0], (size_t)sumsize);
 			cgdirty();
 		}
+		if (debug) {
+			for (i = 0; i < inomapsize; i++) {
+				j = cg_inosused(newcg)[i];
+				k = cg_inosused(cg)[i];
+				if (j == k)
+					continue;
+				for (m = 0, l = 1; m < NBBY; m++, l <<= 1) {
+					if ((j & l) == (k & l))
+						continue;
+					n = c * fs->fs_ipg + i * NBBY + m;
+					if ((j & l) != 0)
+						pwarn("%s INODE %d MARKED %s\n",
+						    "ALLOCATED", n, "FREE");
+					else
+						pwarn("%s INODE %d MARKED %s\n",
+						    "UNALLOCATED", n, "USED");
+				}
+			}
+			astart = ustart = -1;
+			for (i = 0; i < blkmapsize; i++) {
+				j = cg_blksfree(cg)[i];
+				k = cg_blksfree(newcg)[i];
+				if (j == k)
+					continue;
+				for (m = 0, l = 1; m < NBBY; m++, l <<= 1) {
+					if ((j & l) == (k & l))
+						continue;
+					n = c * fs->fs_fpg + i * NBBY + m;
+					if ((j & l) != 0) {
+						if (astart == -1) {
+							astart = aend = n;
+							continue;
+						}
+						if (aend + 1 == n) {
+							aend = n;
+							continue;
+						}
+						pwarn("%s FRAGS %d-%d %s\n",
+						    "ALLOCATED", astart, aend,
+						    "MARKED FREE");
+						astart = aend = n;
+					} else {
+						if (ustart == -1) {
+							ustart = uend = n;
+							continue;
+						}
+						if (uend + 1 == n) {
+							uend = n;
+							continue;
+						}
+						pwarn("%s FRAGS %d-%d %s\n",
+						    "UNALLOCATED", ustart, uend,
+						    "MARKED USED");
+						ustart = uend = n;
+					}
+				}
+			}
+			if (astart != -1)
+				pwarn("%s FRAGS %d-%d %s\n",
+				    "ALLOCATED", astart, aend,
+				    "MARKED FREE");
+			if (ustart != -1)
+				pwarn("%s FRAGS %d-%d %s\n",
+				    "UNALLOCATED", ustart, uend,
+				    "MARKED USED");
+		}
 		if (usedsoftdep) {
 			for (i = 0; i < inomapsize; i++) {
 				j = cg_inosused(newcg)[i];

sbin/fsck/setup.c

@@ -82,6 +82,7 @@ setup(dev)
 
 	havesb = 0;
 	fswritefd = -1;
+	cursnapshot = 0;
 	skipclean = fflag ? 0 : preen;
 	if (stat(dev, &statb) < 0) {
 		printf("Can't stat %s: %s\n", dev, strerror(errno));
@@ -89,9 +90,13 @@ setup(dev)
 	}
 	if ((statb.st_mode & S_IFMT) != S_IFCHR &&
 	    (statb.st_mode & S_IFMT) != S_IFBLK) {
-		pfatal("%s is not a disk device", dev);
+		if ((statb.st_flags & SF_SNAPSHOT) != 0) {
-		if (reply("CONTINUE") == 0)
+			cursnapshot = statb.st_ino;
-			return (0);
+		} else {
+			pfatal("%s is not a disk device", dev);
+			if (reply("CONTINUE") == 0)
+				return (0);
+		}
 	}
 	if ((fsreadfd = open(dev, O_RDONLY)) < 0) {
 		printf("Can't open %s: %s\n", dev, strerror(errno));
@@ -378,6 +383,8 @@ readsb(listerr)
 	memmove(altsblock.fs_csp, sblock.fs_csp, sizeof sblock.fs_csp);
 	altsblock.fs_maxcluster = sblock.fs_maxcluster;
 	memmove(altsblock.fs_fsmnt, sblock.fs_fsmnt, sizeof sblock.fs_fsmnt);
+	memmove(altsblock.fs_snapinum, sblock.fs_snapinum,
+		sizeof sblock.fs_snapinum);
 	memmove(altsblock.fs_sparecon,
 		sblock.fs_sparecon, sizeof sblock.fs_sparecon);
 	/*

sbin/fsck_ffs/dir.c

@@ -241,7 +241,7 @@ dircheck(idesc, dp)
 	if (dp->d_reclen == 0 ||
 	    dp->d_reclen > spaceleft ||
 	    (dp->d_reclen & 0x3) != 0)
-		return (0);
+		goto bad;
 	if (dp->d_ino == 0)
 		return (1);
 	size = DIRSIZ(!newinofmt, dp);
@@ -261,13 +261,19 @@ dircheck(idesc, dp)
 	    idesc->id_filesize < size ||
 	    namlen > MAXNAMLEN ||
 	    type > 15)
-		return (0);
+		goto bad;
 	for (cp = dp->d_name, size = 0; size < namlen; size++)
 		if (*cp == '\0' || (*cp++ == '/'))
-			return (0);
+			goto bad;
 	if (*cp != '\0')
-		return (0);
+		goto bad;
 	return (1);
+bad:
+	if (debug)
+		printf("Bad dir: ino %d reclen %d namlen %d type %d name %s\n",
+		    dp->d_ino, dp->d_reclen, dp->d_namlen, dp->d_type,
+		    dp->d_name);
+	return (0);
 }
 
 void

sbin/fsck_ffs/fsck.h

@@ -114,12 +114,14 @@ struct bufarea *pbp;		/* current inode block */
 #define	cgrp		(*cgblk.b_un.b_cg)
 
 enum fixstate {DONTKNOW, NOFIX, FIX, IGNORE};
+ino_t cursnapshot;
 
 struct inodesc {
 	enum fixstate id_fix;	/* policy on fixing errors */
 	int (*id_func)();	/* function to be applied to blocks of inode */
 	ino_t id_number;	/* inode number described */
 	ino_t id_parent;	/* for DATA nodes, their parent */
+	int id_lbn;		/* logical block number of current block */
 	ufs_daddr_t id_blkno;	/* current block number being examined */
 	int id_numfrags;	/* number of frags contained in block */
 	quad_t id_filesize;	/* for DATA nodes, the size of the directory */
@@ -130,8 +132,9 @@ struct inodesc {
 	char id_type;		/* type of descriptor, DATA or ADDR */
 };
 /* file types */
-#define	DATA	1
+#define	DATA	1	/* a directory */
-#define	ADDR	2
+#define	SNAP	2	/* a snapshot */
+#define	ADDR	3	/* anything but a directory or a snapshot */
 
 /*
  * Linked list of duplicate blocks.

sbin/fsck_ffs/inode.c

@@ -71,6 +71,7 @@ ckinode(dp, idesc)
 
 	if (idesc->id_fix != IGNORE)
 		idesc->id_fix = DONTKNOW;
+	idesc->id_lbn = -1;
 	idesc->id_entryno = 0;
 	idesc->id_filesize = dp->di_size;
 	mode = dp->di_mode & IFMT;
@@ -80,6 +81,7 @@ ckinode(dp, idesc)
 	dino = *dp;
 	ndb = howmany(dino.di_size, sblock.fs_bsize);
 	for (ap = &dino.di_db[0]; ap < &dino.di_db[NDADDR]; ap++) {
+		idesc->id_lbn++;
 		if (--ndb == 0 && (offset = blkoff(&sblock, dino.di_size)) != 0)
 			idesc->id_numfrags =
 				numfrags(&sblock, fragroundup(&sblock, offset));
@@ -106,7 +108,7 @@ ckinode(dp, idesc)
 			continue;
 		}
 		idesc->id_blkno = *ap;
-		if (idesc->id_type == ADDR)
+		if (idesc->id_type != DATA)
 			ret = (*idesc->id_func)(idesc);
 		else
 			ret = dirscan(idesc);
@@ -117,12 +119,14 @@ ckinode(dp, idesc)
 	remsize = dino.di_size - sblock.fs_bsize * NDADDR;
 	sizepb = sblock.fs_bsize;
 	for (ap = &dino.di_ib[0], n = 1; n <= NIADDR; ap++, n++) {
+		sizepb *= NINDIR(&sblock);
 		if (*ap) {
 			idesc->id_blkno = *ap;
 			ret = iblock(idesc, n, remsize);
 			if (ret & STOP)
 				return (ret);
 		} else {
+			idesc->id_lbn += sizepb / sblock.fs_bsize;
 			if (idesc->id_type == DATA && remsize > 0) {
 				/* An empty block in a directory XXX */
 				getpathname(pathbuf, idesc->id_number,
@@ -141,7 +145,6 @@ ckinode(dp, idesc)
                         	}
 			}
 		}
-		sizepb *= NINDIR(&sblock);
 		remsize -= sizepb;
 	}
 	return (KEEPON);
@@ -162,7 +165,7 @@ iblock(idesc, ilevel, isize)
 	char pathbuf[MAXPATHLEN + 1];
 	struct dinode *dp;
 
-	if (idesc->id_type == ADDR) {
+	if (idesc->id_type != DATA) {
 		func = idesc->id_func;
 		if (((n = (*func)(idesc)) & KEEPON) == 0)
 			return (n);
@@ -193,6 +196,8 @@ iblock(idesc, ilevel, isize)
 	}
 	aplim = &bp->b_un.b_indir[nif];
 	for (ap = bp->b_un.b_indir; ap < aplim; ap++) {
+		if (ilevel == 0)
+			idesc->id_lbn++;
 		if (*ap) {
 			idesc->id_blkno = *ap;
 			if (ilevel == 0)

sbin/fsck_ffs/pass1.c

@@ -40,6 +40,7 @@ static const char rcsid[] =
 #endif /* not lint */
 
 #include <sys/param.h>
+#include <sys/stat.h>
 
 #include <ufs/ufs/dinode.h>
 #include <ufs/ufs/dir.h>
@@ -82,7 +83,6 @@ pass1()
 	 * Find all allocated blocks.
 	 */
 	memset(&idesc, 0, sizeof(struct inodesc));
-	idesc.id_type = ADDR;
 	idesc.id_func = pass1check;
 	n_files = n_blks = 0;
 	for (c = 0; c < sblock.fs_ncg; c++) {
@@ -306,6 +306,10 @@ checkinode(inumber, idesc)
 	}
 	badblk = dupblk = 0;
 	idesc->id_number = inumber;
+	if (dp->di_flags & SF_SNAPSHOT)
+		idesc->id_type = SNAP;
+	else
+		idesc->id_type = ADDR;
 	(void)ckinode(dp, idesc);
 	idesc->id_entryno *= btodb(sblock.fs_fsize);
 	if (dp->di_blocks != idesc->id_entryno) {
@@ -341,6 +345,21 @@ pass1check(idesc)
 	register struct dups *dlp;
 	struct dups *new;
 
+	if (idesc->id_type == SNAP) {
+		if (blkno == BLK_NOCOPY)
+			return (KEEPON);
+		if (idesc->id_number == cursnapshot) {
+			if (blkno == blkstofrags(&sblock, idesc->id_lbn))
+				return (KEEPON);
+			if (blkno == BLK_SNAP) {
+				blkno = blkstofrags(&sblock, idesc->id_lbn);
+				idesc->id_entryno -= idesc->id_numfrags;
+			}
+		} else {
+			if (blkno == BLK_SNAP)
+				return (KEEPON);
+		}
+	}
 	if ((anyout = chkrange(blkno, idesc->id_numfrags)) != 0) {
 		blkerror(idesc->id_number, "BAD", blkno);
 		if (badblk++ >= MAXBAD) {

sbin/fsck_ffs/pass5.c

@@ -53,12 +53,12 @@ void
 pass5()
 {
 	int c, blk, frags, basesize, sumsize, mapsize, savednrpos = 0;
-	int inomapsize, blkmapsize;
+	int inomapsize, blkmapsize, astart, aend, ustart, uend;
 	struct fs *fs = &sblock;
 	struct cg *cg = &cgrp;
 	ufs_daddr_t dbase, dmax;
 	ufs_daddr_t d;
-	long i, j, k;
+	long i, j, k, l, m, n;
 	struct csum *cs;
 	struct csum cstotal;
 	struct inodesc idesc[3];
@@ -314,6 +314,72 @@ pass5()
 			       &cg_blktot(newcg)[0], (size_t)sumsize);
 			cgdirty();
 		}
+		if (debug) {
+			for (i = 0; i < inomapsize; i++) {
+				j = cg_inosused(newcg)[i];
+				k = cg_inosused(cg)[i];
+				if (j == k)
+					continue;
+				for (m = 0, l = 1; m < NBBY; m++, l <<= 1) {
+					if ((j & l) == (k & l))
+						continue;
+					n = c * fs->fs_ipg + i * NBBY + m;
+					if ((j & l) != 0)
+						pwarn("%s INODE %d MARKED %s\n",
+						    "ALLOCATED", n, "FREE");
+					else
+						pwarn("%s INODE %d MARKED %s\n",
+						    "UNALLOCATED", n, "USED");
+				}
+			}
+			astart = ustart = -1;
+			for (i = 0; i < blkmapsize; i++) {
+				j = cg_blksfree(cg)[i];
+				k = cg_blksfree(newcg)[i];
+				if (j == k)
+					continue;
+				for (m = 0, l = 1; m < NBBY; m++, l <<= 1) {
+					if ((j & l) == (k & l))
+						continue;
+					n = c * fs->fs_fpg + i * NBBY + m;
+					if ((j & l) != 0) {
+						if (astart == -1) {
+							astart = aend = n;
+							continue;
+						}
+						if (aend + 1 == n) {
+							aend = n;
+							continue;
+						}
+						pwarn("%s FRAGS %d-%d %s\n",
+						    "ALLOCATED", astart, aend,
+						    "MARKED FREE");
+						astart = aend = n;
+					} else {
+						if (ustart == -1) {
+							ustart = uend = n;
+							continue;
+						}
+						if (uend + 1 == n) {
+							uend = n;
+							continue;
+						}
+						pwarn("%s FRAGS %d-%d %s\n",
+						    "UNALLOCATED", ustart, uend,
+						    "MARKED USED");
+						ustart = uend = n;
+					}
+				}
+			}
+			if (astart != -1)
+				pwarn("%s FRAGS %d-%d %s\n",
+				    "ALLOCATED", astart, aend,
+				    "MARKED FREE");
+			if (ustart != -1)
+				pwarn("%s FRAGS %d-%d %s\n",
+				    "UNALLOCATED", ustart, uend,
+				    "MARKED USED");
+		}
 		if (usedsoftdep) {
 			for (i = 0; i < inomapsize; i++) {
 				j = cg_inosused(newcg)[i];

sbin/fsck_ffs/setup.c

@@ -82,6 +82,7 @@ setup(dev)
 
 	havesb = 0;
 	fswritefd = -1;
+	cursnapshot = 0;
 	skipclean = fflag ? 0 : preen;
 	if (stat(dev, &statb) < 0) {
 		printf("Can't stat %s: %s\n", dev, strerror(errno));
@@ -89,9 +90,13 @@ setup(dev)
 	}
 	if ((statb.st_mode & S_IFMT) != S_IFCHR &&
 	    (statb.st_mode & S_IFMT) != S_IFBLK) {
-		pfatal("%s is not a disk device", dev);
+		if ((statb.st_flags & SF_SNAPSHOT) != 0) {
-		if (reply("CONTINUE") == 0)
+			cursnapshot = statb.st_ino;
-			return (0);
+		} else {
+			pfatal("%s is not a disk device", dev);
+			if (reply("CONTINUE") == 0)
+				return (0);
+		}
 	}
 	if ((fsreadfd = open(dev, O_RDONLY)) < 0) {
 		printf("Can't open %s: %s\n", dev, strerror(errno));
@@ -378,6 +383,8 @@ readsb(listerr)
 	memmove(altsblock.fs_csp, sblock.fs_csp, sizeof sblock.fs_csp);
 	altsblock.fs_maxcluster = sblock.fs_maxcluster;
 	memmove(altsblock.fs_fsmnt, sblock.fs_fsmnt, sizeof sblock.fs_fsmnt);
+	memmove(altsblock.fs_snapinum, sblock.fs_snapinum,
+		sizeof sblock.fs_snapinum);
 	memmove(altsblock.fs_sparecon,
 		sblock.fs_sparecon, sizeof sblock.fs_sparecon);
 	/*

sbin/fsck_ifs/dir.c

@@ -241,7 +241,7 @@ dircheck(idesc, dp)
 	if (dp->d_reclen == 0 ||
 	    dp->d_reclen > spaceleft ||
 	    (dp->d_reclen & 0x3) != 0)
-		return (0);
+		goto bad;
 	if (dp->d_ino == 0)
 		return (1);
 	size = DIRSIZ(!newinofmt, dp);
@@ -261,13 +261,19 @@ dircheck(idesc, dp)
 	    idesc->id_filesize < size ||
 	    namlen > MAXNAMLEN ||
 	    type > 15)
-		return (0);
+		goto bad;
 	for (cp = dp->d_name, size = 0; size < namlen; size++)
 		if (*cp == '\0' || (*cp++ == '/'))
-			return (0);
+			goto bad;
 	if (*cp != '\0')
-		return (0);
+		goto bad;
 	return (1);
+bad:
+	if (debug)
+		printf("Bad dir: ino %d reclen %d namlen %d type %d name %s\n",
+		    dp->d_ino, dp->d_reclen, dp->d_namlen, dp->d_type,
+		    dp->d_name);
+	return (0);
 }
 
 void

sbin/fsck_ifs/fsck.h

@@ -114,12 +114,14 @@ struct bufarea *pbp;		/* current inode block */
 #define	cgrp		(*cgblk.b_un.b_cg)
 
 enum fixstate {DONTKNOW, NOFIX, FIX, IGNORE};
+ino_t cursnapshot;
 
 struct inodesc {
 	enum fixstate id_fix;	/* policy on fixing errors */
 	int (*id_func)();	/* function to be applied to blocks of inode */
 	ino_t id_number;	/* inode number described */
 	ino_t id_parent;	/* for DATA nodes, their parent */
+	int id_lbn;		/* logical block number of current block */
 	ufs_daddr_t id_blkno;	/* current block number being examined */
 	int id_numfrags;	/* number of frags contained in block */
 	quad_t id_filesize;	/* for DATA nodes, the size of the directory */
@@ -130,8 +132,9 @@ struct inodesc {
 	char id_type;		/* type of descriptor, DATA or ADDR */
 };
 /* file types */
-#define	DATA	1
+#define	DATA	1	/* a directory */
-#define	ADDR	2
+#define	SNAP	2	/* a snapshot */
+#define	ADDR	3	/* anything but a directory or a snapshot */
 
 /*
  * Linked list of duplicate blocks.

sbin/fsck_ifs/inode.c

@@ -71,6 +71,7 @@ ckinode(dp, idesc)
 
 	if (idesc->id_fix != IGNORE)
 		idesc->id_fix = DONTKNOW;
+	idesc->id_lbn = -1;
 	idesc->id_entryno = 0;
 	idesc->id_filesize = dp->di_size;
 	mode = dp->di_mode & IFMT;
@@ -80,6 +81,7 @@ ckinode(dp, idesc)
 	dino = *dp;
 	ndb = howmany(dino.di_size, sblock.fs_bsize);
 	for (ap = &dino.di_db[0]; ap < &dino.di_db[NDADDR]; ap++) {
+		idesc->id_lbn++;
 		if (--ndb == 0 && (offset = blkoff(&sblock, dino.di_size)) != 0)
 			idesc->id_numfrags =
 				numfrags(&sblock, fragroundup(&sblock, offset));
@@ -106,7 +108,7 @@ ckinode(dp, idesc)
 			continue;
 		}
 		idesc->id_blkno = *ap;
-		if (idesc->id_type == ADDR)
+		if (idesc->id_type != DATA)
 			ret = (*idesc->id_func)(idesc);
 		else
 			ret = dirscan(idesc);
@@ -117,12 +119,14 @@ ckinode(dp, idesc)
 	remsize = dino.di_size - sblock.fs_bsize * NDADDR;
 	sizepb = sblock.fs_bsize;
 	for (ap = &dino.di_ib[0], n = 1; n <= NIADDR; ap++, n++) {
+		sizepb *= NINDIR(&sblock);
 		if (*ap) {
 			idesc->id_blkno = *ap;
 			ret = iblock(idesc, n, remsize);
 			if (ret & STOP)
 				return (ret);
 		} else {
+			idesc->id_lbn += sizepb / sblock.fs_bsize;
 			if (idesc->id_type == DATA && remsize > 0) {
 				/* An empty block in a directory XXX */
 				getpathname(pathbuf, idesc->id_number,
@@ -141,7 +145,6 @@ ckinode(dp, idesc)
                         	}
 			}
 		}
-		sizepb *= NINDIR(&sblock);
 		remsize -= sizepb;
 	}
 	return (KEEPON);
@@ -162,7 +165,7 @@ iblock(idesc, ilevel, isize)
 	char pathbuf[MAXPATHLEN + 1];
 	struct dinode *dp;
 
-	if (idesc->id_type == ADDR) {
+	if (idesc->id_type != DATA) {
 		func = idesc->id_func;
 		if (((n = (*func)(idesc)) & KEEPON) == 0)
 			return (n);
@@ -193,6 +196,8 @@ iblock(idesc, ilevel, isize)
 	}
 	aplim = &bp->b_un.b_indir[nif];
 	for (ap = bp->b_un.b_indir; ap < aplim; ap++) {
+		if (ilevel == 0)
+			idesc->id_lbn++;
 		if (*ap) {
 			idesc->id_blkno = *ap;
 			if (ilevel == 0)

sbin/fsck_ifs/pass1.c

@@ -40,6 +40,7 @@ static const char rcsid[] =
 #endif /* not lint */
 
 #include <sys/param.h>
+#include <sys/stat.h>
 
 #include <ufs/ufs/dinode.h>
 #include <ufs/ufs/dir.h>
@@ -82,7 +83,6 @@ pass1()
 	 * Find all allocated blocks.
 	 */
 	memset(&idesc, 0, sizeof(struct inodesc));
-	idesc.id_type = ADDR;
 	idesc.id_func = pass1check;
 	n_files = n_blks = 0;
 	for (c = 0; c < sblock.fs_ncg; c++) {
@@ -306,6 +306,10 @@ checkinode(inumber, idesc)
 	}
 	badblk = dupblk = 0;
 	idesc->id_number = inumber;
+	if (dp->di_flags & SF_SNAPSHOT)
+		idesc->id_type = SNAP;
+	else
+		idesc->id_type = ADDR;
 	(void)ckinode(dp, idesc);
 	idesc->id_entryno *= btodb(sblock.fs_fsize);
 	if (dp->di_blocks != idesc->id_entryno) {
@@ -341,6 +345,21 @@ pass1check(idesc)
 	register struct dups *dlp;
 	struct dups *new;
 
+	if (idesc->id_type == SNAP) {
+		if (blkno == BLK_NOCOPY)
+			return (KEEPON);
+		if (idesc->id_number == cursnapshot) {
+			if (blkno == blkstofrags(&sblock, idesc->id_lbn))
+				return (KEEPON);
+			if (blkno == BLK_SNAP) {
+				blkno = blkstofrags(&sblock, idesc->id_lbn);
+				idesc->id_entryno -= idesc->id_numfrags;
+			}
+		} else {
+			if (blkno == BLK_SNAP)
+				return (KEEPON);
+		}
+	}
 	if ((anyout = chkrange(blkno, idesc->id_numfrags)) != 0) {
 		blkerror(idesc->id_number, "BAD", blkno);
 		if (badblk++ >= MAXBAD) {

sbin/fsck_ifs/pass5.c

@@ -53,12 +53,12 @@ void
 pass5()
 {
 	int c, blk, frags, basesize, sumsize, mapsize, savednrpos = 0;
-	int inomapsize, blkmapsize;
+	int inomapsize, blkmapsize, astart, aend, ustart, uend;
 	struct fs *fs = &sblock;
 	struct cg *cg = &cgrp;
 	ufs_daddr_t dbase, dmax;
 	ufs_daddr_t d;
-	long i, j, k;
+	long i, j, k, l, m, n;
 	struct csum *cs;
 	struct csum cstotal;
 	struct inodesc idesc[3];
@@ -314,6 +314,72 @@ pass5()
 			       &cg_blktot(newcg)[0], (size_t)sumsize);
 			cgdirty();
 		}
+		if (debug) {
+			for (i = 0; i < inomapsize; i++) {
+				j = cg_inosused(newcg)[i];
+				k = cg_inosused(cg)[i];
+				if (j == k)
+					continue;
+				for (m = 0, l = 1; m < NBBY; m++, l <<= 1) {
+					if ((j & l) == (k & l))
+						continue;
+					n = c * fs->fs_ipg + i * NBBY + m;
+					if ((j & l) != 0)
+						pwarn("%s INODE %d MARKED %s\n",
+						    "ALLOCATED", n, "FREE");
+					else
+						pwarn("%s INODE %d MARKED %s\n",
+						    "UNALLOCATED", n, "USED");
+				}
+			}
+			astart = ustart = -1;
+			for (i = 0; i < blkmapsize; i++) {
+				j = cg_blksfree(cg)[i];
+				k = cg_blksfree(newcg)[i];
+				if (j == k)
+					continue;
+				for (m = 0, l = 1; m < NBBY; m++, l <<= 1) {
+					if ((j & l) == (k & l))
+						continue;
+					n = c * fs->fs_fpg + i * NBBY + m;
+					if ((j & l) != 0) {
+						if (astart == -1) {
+							astart = aend = n;
+							continue;
+						}
+						if (aend + 1 == n) {
+							aend = n;
+							continue;
+						}
+						pwarn("%s FRAGS %d-%d %s\n",
+						    "ALLOCATED", astart, aend,
+						    "MARKED FREE");
+						astart = aend = n;
+					} else {
+						if (ustart == -1) {
+							ustart = uend = n;
+							continue;
+						}
+						if (uend + 1 == n) {
+							uend = n;
+							continue;
+						}
+						pwarn("%s FRAGS %d-%d %s\n",
+						    "UNALLOCATED", ustart, uend,
+						    "MARKED USED");
+						ustart = uend = n;
+					}
+				}
+			}
+			if (astart != -1)
+				pwarn("%s FRAGS %d-%d %s\n",
+				    "ALLOCATED", astart, aend,
+				    "MARKED FREE");
+			if (ustart != -1)
+				pwarn("%s FRAGS %d-%d %s\n",
+				    "UNALLOCATED", ustart, uend,
+				    "MARKED USED");
+		}
 		if (usedsoftdep) {
 			for (i = 0; i < inomapsize; i++) {
 				j = cg_inosused(newcg)[i];

sbin/fsck_ifs/setup.c

@@ -82,6 +82,7 @@ setup(dev)
 
 	havesb = 0;
 	fswritefd = -1;
+	cursnapshot = 0;
 	skipclean = fflag ? 0 : preen;
 	if (stat(dev, &statb) < 0) {
 		printf("Can't stat %s: %s\n", dev, strerror(errno));
@@ -89,9 +90,13 @@ setup(dev)
 	}
 	if ((statb.st_mode & S_IFMT) != S_IFCHR &&
 	    (statb.st_mode & S_IFMT) != S_IFBLK) {
-		pfatal("%s is not a disk device", dev);
+		if ((statb.st_flags & SF_SNAPSHOT) != 0) {
-		if (reply("CONTINUE") == 0)
+			cursnapshot = statb.st_ino;
-			return (0);
+		} else {
+			pfatal("%s is not a disk device", dev);
+			if (reply("CONTINUE") == 0)
+				return (0);
+		}
 	}
 	if ((fsreadfd = open(dev, O_RDONLY)) < 0) {
 		printf("Can't open %s: %s\n", dev, strerror(errno));
@@ -378,6 +383,8 @@ readsb(listerr)
 	memmove(altsblock.fs_csp, sblock.fs_csp, sizeof sblock.fs_csp);
 	altsblock.fs_maxcluster = sblock.fs_maxcluster;
 	memmove(altsblock.fs_fsmnt, sblock.fs_fsmnt, sizeof sblock.fs_fsmnt);
+	memmove(altsblock.fs_snapinum, sblock.fs_snapinum,
+		sizeof sblock.fs_snapinum);
 	memmove(altsblock.fs_sparecon,
 		sblock.fs_sparecon, sizeof sblock.fs_sparecon);
 	/*