- *
- * The root inode is the root of the file system.
- * Inode 0 can't be used for normal purposes and
- * historically bad blocks were linked to inode 1,
- * thus the root inode is 2. (inode 1 is no longer used for
- * this purpose, however numerous dump tapes make this
- * assumption, so we are stuck with it)
- * The lost+found directory is given the next available
- * inode when it is created by ``mkfs''.
- */
-#define ROOTINO ((ino_t)2) /* i number of all roots */
-#define LOSTFOUNDINO (ROOTINO + 1)
-
-/*
- * MINFREE gives the minimum acceptable percentage of file system
- * blocks which may be free. If the freelist drops below this level
- * only the superuser may continue to allocate blocks. This may
- * be set to 0 if no reserve of free blocks is deemed necessary,
- * however severe performance degredations will be observed if the
- * file system is run at greater than 90% full; thus the default
- * value of fs_minfree is 10%.
- *
- * Empirically the best trade-off between block fragmentation and
- * overall disk utilization at a loading of 90% comes with a
- * fragmentation of 4, thus the default fragment size is a fourth
- * of the block size.
- */
-#define MINFREE 10
-#define DESFRAG 4
-
-/*
- * Under current technology, most 300MB disks have 32 sectors and
- * 16 tracks, thus these are the defaults used for fs_nsect and
- * fs_ntrak respectively.
- */
-#define DFLNSECT 32
-#define DFLNTRAK 16
-
-/*
- * Cylinder group related limits.
- *
- * For each cylinder we keep track of the availability of blocks at different
- * rotational positions, so that we can lay out the data to be picked
- * up with minimum rotational latency. NRPOS is the number of rotational
- * positions which we distinguish. With NRPOS 8 the resolution of our
- * summary information is 2ms for a typical 3600 rpm drive.
- *
- * ROTDELAY gives the minimum number of milliseconds to initiate
- * another disk transfer on the same cylinder. It is used in
- * determining the rotationally optimal layout for disk blocks
- * within a file; the default of fs_rotdelay is 2ms.
- */
-#define NRPOS 8 /* number distinct rotational positions */
-#define ROTDELAY 2
-
-/*
- * Each file system has a number of inodes statically allocated.
- * We allocate one inode slot per NBPI bytes, expecting this
- * to be far more than we will ever need.
- *
- * MAXIPG bounds the number of inodes per cylinder group, and
- * is needed only to keep the structure simpler by having the
- * only a single variable size element (the free bit map).
- *
- * N.B.: MAXIPG must be a multiple of INOPB(fs).