fs/jfs: Remove dead code

Since the JFS code was first added to Linux, there has been code hidden
in ifdefs  for some potential future features such as defragmentation
and supporting block sizes other than 4KB. There has been no ongoing
development on JFS for many years, so it's past time to remove this dead
code from the source.

Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>

fs/jfs/Makefile

@@ -13,5 +13,3 @@ jfs-y    := super.o file.o inode.o namei.o jfs_mount.o jfs_umount.o \
 	    resize.o xattr.o ioctl.o
 
 jfs-$(CONFIG_JFS_POSIX_ACL) += acl.o
-
-ccflags-y := -D_JFS_4K

fs/jfs/inode.c

@@ -224,18 +224,9 @@ int jfs_get_block(struct inode *ip, sector_t lblock,
 				 * this as a hole
 				 */
 				goto unlock;
-#ifdef _JFS_4K
 			XADoffset(&xad, lblock64);
 			XADlength(&xad, xlen);
 			XADaddress(&xad, xaddr);
-#else				/* _JFS_4K */
-			/*
-			 * As long as block size = 4K, this isn't a problem.
-			 * We should mark the whole page not ABNR, but how
-			 * will we know to mark the other blocks BH_New?
-			 */
-			BUG();
-#endif				/* _JFS_4K */
 			rc = extRecord(ip, &xad);
 			if (rc)
 				goto unlock;
@@ -252,7 +243,6 @@ int jfs_get_block(struct inode *ip, sector_t lblock,
 	/*
 	 * Allocate a new block
 	 */
-#ifdef _JFS_4K
 	if ((rc = extHint(ip, lblock64 << ip->i_sb->s_blocksize_bits, &xad)))
 		goto unlock;
 	rc = extAlloc(ip, xlen, lblock64, &xad, false);
@@ -263,14 +253,6 @@ int jfs_get_block(struct inode *ip, sector_t lblock,
 	map_bh(bh_result, ip->i_sb, addressXAD(&xad));
 	bh_result->b_size = lengthXAD(&xad) << ip->i_blkbits;
 
-#else				/* _JFS_4K */
-	/*
-	 * We need to do whatever it takes to keep all but the last buffers
-	 * in 4K pages - see jfs_write.c
-	 */
-	BUG();
-#endif				/* _JFS_4K */
-
       unlock:
 	/*
 	 * Release lock on inode

fs/jfs/jfs_dmap.c

@@ -869,74 +869,6 @@ int dbAlloc(struct inode *ip, s64 hint, s64 nblocks, s64 * results)
 	return (rc);
 }
 
-#ifdef _NOTYET
-/*
- * NAME:	dbAllocExact()
- *
- * FUNCTION:	try to allocate the requested extent;
- *
- * PARAMETERS:
- *	ip	- pointer to in-core inode;
- *	blkno	- extent address;
- *	nblocks	- extent length;
- *
- * RETURN VALUES:
- *	0	- success
- *	-ENOSPC	- insufficient disk resources
- *	-EIO	- i/o error
- */
-int dbAllocExact(struct inode *ip, s64 blkno, int nblocks)
-{
-	int rc;
-	struct inode *ipbmap = JFS_SBI(ip->i_sb)->ipbmap;
-	struct bmap *bmp = JFS_SBI(ip->i_sb)->bmap;
-	struct dmap *dp;
-	s64 lblkno;
-	struct metapage *mp;
-
-	IREAD_LOCK(ipbmap, RDWRLOCK_DMAP);
-
-	/*
-	 * validate extent request:
-	 *
-	 * note: defragfs policy:
-	 *  max 64 blocks will be moved.
-	 *  allocation request size must be satisfied from a single dmap.
-	 */
-	if (nblocks <= 0 || nblocks > BPERDMAP || blkno >= bmp->db_mapsize) {
-		IREAD_UNLOCK(ipbmap);
-		return -EINVAL;
-	}
-
-	if (nblocks > ((s64) 1 << bmp->db_maxfreebud)) {
-		/* the free space is no longer available */
-		IREAD_UNLOCK(ipbmap);
-		return -ENOSPC;
-	}
-
-	/* read in the dmap covering the extent */
-	lblkno = BLKTODMAP(blkno, bmp->db_l2nbperpage);
-	mp = read_metapage(ipbmap, lblkno, PSIZE, 0);
-	if (mp == NULL) {
-		IREAD_UNLOCK(ipbmap);
-		return -EIO;
-	}
-	dp = (struct dmap *) mp->data;
-
-	/* try to allocate the requested extent */
-	rc = dbAllocNext(bmp, dp, blkno, nblocks);
-
-	IREAD_UNLOCK(ipbmap);
-
-	if (rc == 0)
-		mark_metapage_dirty(mp);
-
-	release_metapage(mp);
-
-	return (rc);
-}
-#endif /* _NOTYET */
-
 /*
  * NAME:	dbReAlloc()
  *