BSD 4.4 Lite Kernel Sources

1 files changed, 238 insertions, 0 deletions

diff --git a/sys/ufs/ffs/ffs_subr.c b/sys/ufs/ffs/ffs_subr.c
new file mode 100644
index 0000000..c251b16
--- /dev/null
+++ b/sys/ufs/ffs/ffs_subr.c
@@ -0,0 +1,238 @@
+/*
+ * Copyright (c) 1982, 1986, 1989, 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.
+ *
+ *	@(#)ffs_subr.c	8.2 (Berkeley) 9/21/93
+ */
+
+#include <sys/param.h>
+#include <ufs/ffs/fs.h>
+
+#ifdef KERNEL
+#include <sys/systm.h>
+#include <sys/vnode.h>
+#include <ufs/ffs/ffs_extern.h>
+#include <sys/buf.h>
+#include <ufs/ufs/quota.h>
+#include <ufs/ufs/inode.h>
+
+/*
+ * Return buffer with the contents of block "offset" from the beginning of
+ * directory "ip".  If "res" is non-zero, fill it in with a pointer to the
+ * remaining space in the directory.
+ */
+int
+ffs_blkatoff(ap)
+	struct vop_blkatoff_args /* {
+		struct vnode *a_vp;
+		off_t a_offset;
+		char **a_res;
+		struct buf **a_bpp;
+	} */ *ap;
+{
+	struct inode *ip;
+	register struct fs *fs;
+	struct buf *bp;
+	daddr_t lbn;
+	int bsize, error;
+
+	ip = VTOI(ap->a_vp);
+	fs = ip->i_fs;
+	lbn = lblkno(fs, ap->a_offset);
+	bsize = blksize(fs, ip, lbn);
+
+	*ap->a_bpp = NULL;
+	if (error = bread(ap->a_vp, lbn, bsize, NOCRED, &bp)) {
+		brelse(bp);
+		return (error);
+	}
+	if (ap->a_res)
+		*ap->a_res = (char *)bp->b_data + blkoff(fs, ap->a_offset);
+	*ap->a_bpp = bp;
+	return (0);
+}
+#endif
+
+/*
+ * Update the frsum fields to reflect addition or deletion 
+ * of some frags.
+ */
+void
+ffs_fragacct(fs, fragmap, fraglist, cnt)
+	struct fs *fs;
+	int fragmap;
+	long fraglist[];
+	int cnt;
+{
+	int inblk;
+	register int field, subfield;
+	register int siz, pos;
+
+	inblk = (int)(fragtbl[fs->fs_frag][fragmap]) << 1;
+	fragmap <<= 1;
+	for (siz = 1; siz < fs->fs_frag; siz++) {
+		if ((inblk & (1 << (siz + (fs->fs_frag % NBBY)))) == 0)
+			continue;
+		field = around[siz];
+		subfield = inside[siz];
+		for (pos = siz; pos <= fs->fs_frag; pos++) {
+			if ((fragmap & field) == subfield) {
+				fraglist[siz] += cnt;
+				pos += siz;
+				field <<= siz;
+				subfield <<= siz;
+			}
+			field <<= 1;
+			subfield <<= 1;
+		}
+	}
+}
+
+#if defined(KERNEL) && defined(DIAGNOSTIC)
+void
+ffs_checkoverlap(bp, ip)
+	struct buf *bp;
+	struct inode *ip;
+{
+	register struct buf *ebp, *ep;
+	register daddr_t start, last;
+	struct vnode *vp;
+
+	ebp = &buf[nbuf];
+	start = bp->b_blkno;
+	last = start + btodb(bp->b_bcount) - 1;
+	for (ep = buf; ep < ebp; ep++) {
+		if (ep == bp || (ep->b_flags & B_INVAL) ||
+		    ep->b_vp == NULLVP)
+			continue;
+		if (VOP_BMAP(ep->b_vp, (daddr_t)0, &vp, (daddr_t)0, NULL))
+			continue;
+		if (vp != ip->i_devvp)
+			continue;
+		/* look for overlap */
+		if (ep->b_bcount == 0 || ep->b_blkno > last ||
+		    ep->b_blkno + btodb(ep->b_bcount) <= start)
+			continue;
+		vprint("Disk overlap", vp);
+		(void)printf("\tstart %d, end %d overlap start %d, end %d\n",
+			start, last, ep->b_blkno,
+			ep->b_blkno + btodb(ep->b_bcount) - 1);
+		panic("Disk buffer overlap");
+	}
+}
+#endif /* DIAGNOSTIC */
+
+/*
+ * block operations
+ *
+ * check if a block is available
+ */
+int
+ffs_isblock(fs, cp, h)
+	struct fs *fs;
+	unsigned char *cp;
+	daddr_t h;
+{
+	unsigned char mask;
+
+	switch ((int)fs->fs_frag) {
+	case 8:
+		return (cp[h] == 0xff);
+	case 4:
+		mask = 0x0f << ((h & 0x1) << 2);
+		return ((cp[h >> 1] & mask) == mask);
+	case 2:
+		mask = 0x03 << ((h & 0x3) << 1);
+		return ((cp[h >> 2] & mask) == mask);
+	case 1:
+		mask = 0x01 << (h & 0x7);
+		return ((cp[h >> 3] & mask) == mask);
+	default:
+		panic("ffs_isblock");
+	}
+}
+
+/*
+ * take a block out of the map
+ */
+void
+ffs_clrblock(fs, cp, h)
+	struct fs *fs;
+	u_char *cp;
+	daddr_t h;
+{
+
+	switch ((int)fs->fs_frag) {
+	case 8:
+		cp[h] = 0;
+		return;
+	case 4:
+		cp[h >> 1] &= ~(0x0f << ((h & 0x1) << 2));
+		return;
+	case 2:
+		cp[h >> 2] &= ~(0x03 << ((h & 0x3) << 1));
+		return;
+	case 1:
+		cp[h >> 3] &= ~(0x01 << (h & 0x7));
+		return;
+	default:
+		panic("ffs_clrblock");
+	}
+}
+
+/*
+ * put a block into the map
+ */
+void
+ffs_setblock(fs, cp, h)
+	struct fs *fs;
+	unsigned char *cp;
+	daddr_t h;
+{
+
+	switch ((int)fs->fs_frag) {
+
+	case 8:
+		cp[h] = 0xff;
+		return;
+	case 4:
+		cp[h >> 1] |= (0x0f << ((h & 0x1) << 2));
+		return;
+	case 2:
+		cp[h >> 2] |= (0x03 << ((h & 0x3) << 1));
+		return;
+	case 1:
+		cp[h >> 3] |= (0x01 << (h & 0x7));
+		return;
+	default:
+		panic("ffs_setblock");
+	}
+}