Properly handle UFS2 sparsely allocated inodes. The UFS2 filesystem

only preallocates a small number of inodes. The dump program tries
to scan through all the allocated inodes on a filesystem which
causes bad behavior if they have never been allocated. Thus dump
must calculate the set of inodes that have actually been allocated
and scan only those inodes.

Sponsored by:   DARPA & NAI Labs.

1 files changed, 66 insertions, 25 deletions

diff --git a/sbin/dump/traverse.c b/sbin/dump/traverse.c
index b618cdf..9882283 100644
--- a/sbin/dump/traverse.c
+++ b/sbin/dump/traverse.c
@@ -139,36 +139,77 @@ blockest(union dinode *dp)
 int
 mapfiles(ino_t maxino, long *tapesize)
 {
-	int mode;
-	ino_t ino;
-	union dinode *dp;
+	int i, cg, mode, inosused;
 	int anydirskipped = 0;
+	union dinode *dp;
+	struct cg *cgp;
+	ino_t ino;
+	char *cp;
 
-	for (ino = ROOTINO; ino < maxino; ino++) {
-		dp = getino(ino, &mode);
-		if (mode == 0)
-			continue;
+	if ((cgp = malloc(sblock->fs_cgsize)) == NULL)
+		quit("mapfiles: cannot allocate memory.\n");
+	for (cg = 0; cg < sblock->fs_ncg; cg++) {
+		ino = cg * sblock->fs_ipg;
+		bread(fsbtodb(sblock, cgtod(sblock, cg)), (char *)cgp,
+		    sblock->fs_cgsize);
+		if (sblock->fs_magic == FS_UFS2_MAGIC)
+			inosused = cgp->cg_initediblk;
+		else
+			inosused = sblock->fs_ipg;
 		/*
-		 * Everything must go in usedinomap so that a check
-		 * for "in dumpdirmap but not in usedinomap" to detect
-		 * dirs with nodump set has a chance of succeeding
-		 * (this is used in mapdirs()).
+		 * If we are using soft updates, then we can trust the
+		 * cylinder group inode allocation maps to tell us which
+		 * inodes are allocated. We will scan the used inode map
+		 * to find the inodes that are really in use, and then
+		 * read only those inodes in from disk.
 		 */
-		SETINO(ino, usedinomap);
-		if (mode == IFDIR)
-			SETINO(ino, dumpdirmap);
-		if (WANTTODUMP(dp)) {
-			SETINO(ino, dumpinomap);
-			if (mode != IFREG && mode != IFDIR && mode != IFLNK)
-				*tapesize += 1;
-			else
-				*tapesize += blockest(dp);
-			continue;
+		if (sblock->fs_flags & FS_DOSOFTDEP) {
+			if (!cg_chkmagic(cgp))
+				quit("mapfiles: cg %d: bad magic number\n", cg);
+			cp = &cg_inosused(cgp)[(inosused - 1) / CHAR_BIT];
+			for ( ; inosused > 0; inosused -= CHAR_BIT, cp--) {
+				if (*cp == 0)
+					continue;
+				for (i = 1 << (CHAR_BIT - 1); i > 0; i >>= 1) {
+					if (*cp & i)
+						break;
+					inosused--;
+				}
+				break;
+			}
+			if (inosused <= 0)
+				continue;
 		}
-		if (mode == IFDIR) {
-			if (!nonodump && (DIP(dp, di_flags) & UF_NODUMP))
-				CLRINO(ino, usedinomap);
-			anydirskipped = 1;
+		for (i = 0; i < inosused; i++, ino++) {
+			if (ino < ROOTINO ||
+			    (dp = getino(ino, &mode)) == NULL ||
+			    (mode & IFMT) == 0)
+				continue;
+			/*
+			 * Everything must go in usedinomap so that a check
+			 * for "in dumpdirmap but not in usedinomap" to detect
+			 * dirs with nodump set has a chance of succeeding
+			 * (this is used in mapdirs()).
+			 */
+			SETINO(ino, usedinomap);
+			if (mode == IFDIR)
+				SETINO(ino, dumpdirmap);
+			if (WANTTODUMP(dp)) {
+				SETINO(ino, dumpinomap);
+				if (mode != IFREG &&
+				    mode != IFDIR &&
+				    mode != IFLNK)
+					*tapesize += 1;
+				else
+					*tapesize += blockest(dp);
+				continue;
+			}
+			if (mode == IFDIR) {
+				if (!nonodump &&
+				    (DIP(dp, di_flags) & UF_NODUMP))
+					CLRINO(ino, usedinomap);
+				anydirskipped = 1;
+			}
 		}
 	}
 	/*