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-rw-r--r--fs/freevxfs/vxfs_bmap.c281
1 files changed, 281 insertions, 0 deletions
diff --git a/fs/freevxfs/vxfs_bmap.c b/fs/freevxfs/vxfs_bmap.c
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+++ b/fs/freevxfs/vxfs_bmap.c
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+/*
+ * Copyright (c) 2000-2001 Christoph Hellwig.
+ * 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,
+ * without modification.
+ * 2. The name of the author may not be used to endorse or promote products
+ * derived from this software without specific prior written permission.
+ *
+ * Alternatively, this software may be distributed under the terms of the
+ * GNU General Public License ("GPL").
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
+ */
+
+/*
+ * Veritas filesystem driver - filesystem to disk block mapping.
+ */
+#include <linux/fs.h>
+#include <linux/buffer_head.h>
+#include <linux/kernel.h>
+
+#include "vxfs.h"
+#include "vxfs_inode.h"
+#include "vxfs_extern.h"
+
+
+#ifdef DIAGNOSTIC
+static void
+vxfs_typdump(struct vxfs_typed *typ)
+{
+ printk(KERN_DEBUG "type=%Lu ", typ->vt_hdr >> VXFS_TYPED_TYPESHIFT);
+ printk("offset=%Lx ", typ->vt_hdr & VXFS_TYPED_OFFSETMASK);
+ printk("block=%x ", typ->vt_block);
+ printk("size=%x\n", typ->vt_size);
+}
+#endif
+
+/**
+ * vxfs_bmap_ext4 - do bmap for ext4 extents
+ * @ip: pointer to the inode we do bmap for
+ * @iblock: logical block.
+ *
+ * Description:
+ * vxfs_bmap_ext4 performs the bmap operation for inodes with
+ * ext4-style extents (which are much like the traditional UNIX
+ * inode organisation).
+ *
+ * Returns:
+ * The physical block number on success, else Zero.
+ */
+static daddr_t
+vxfs_bmap_ext4(struct inode *ip, long bn)
+{
+ struct super_block *sb = ip->i_sb;
+ struct vxfs_inode_info *vip = VXFS_INO(ip);
+ unsigned long bsize = sb->s_blocksize;
+ u32 indsize = vip->vii_ext4.ve4_indsize;
+ int i;
+
+ if (indsize > sb->s_blocksize)
+ goto fail_size;
+
+ for (i = 0; i < VXFS_NDADDR; i++) {
+ struct direct *d = vip->vii_ext4.ve4_direct + i;
+ if (bn >= 0 && bn < d->size)
+ return (bn + d->extent);
+ bn -= d->size;
+ }
+
+ if ((bn / (indsize * indsize * bsize / 4)) == 0) {
+ struct buffer_head *buf;
+ daddr_t bno;
+ u32 *indir;
+
+ buf = sb_bread(sb, vip->vii_ext4.ve4_indir[0]);
+ if (!buf || !buffer_mapped(buf))
+ goto fail_buf;
+
+ indir = (u32 *)buf->b_data;
+ bno = indir[(bn/indsize) % (indsize*bn)] + (bn%indsize);
+
+ brelse(buf);
+ return bno;
+ } else
+ printk(KERN_WARNING "no matching indir?");
+
+ return 0;
+
+fail_size:
+ printk("vxfs: indirect extent too big!\n");
+fail_buf:
+ return 0;
+}
+
+/**
+ * vxfs_bmap_indir - recursion for vxfs_bmap_typed
+ * @ip: pointer to the inode we do bmap for
+ * @indir: indirect block we start reading at
+ * @size: size of the typed area to search
+ * @block: partially result from further searches
+ *
+ * Description:
+ * vxfs_bmap_indir reads a &struct vxfs_typed at @indir
+ * and performs the type-defined action.
+ *
+ * Return Value:
+ * The physical block number on success, else Zero.
+ *
+ * Note:
+ * Kernelstack is rare. Unrecurse?
+ */
+static daddr_t
+vxfs_bmap_indir(struct inode *ip, long indir, int size, long block)
+{
+ struct buffer_head *bp = NULL;
+ daddr_t pblock = 0;
+ int i;
+
+ for (i = 0; i < size * VXFS_TYPED_PER_BLOCK(ip->i_sb); i++) {
+ struct vxfs_typed *typ;
+ int64_t off;
+
+ bp = sb_bread(ip->i_sb,
+ indir + (i / VXFS_TYPED_PER_BLOCK(ip->i_sb)));
+ if (!bp || !buffer_mapped(bp))
+ return 0;
+
+ typ = ((struct vxfs_typed *)bp->b_data) +
+ (i % VXFS_TYPED_PER_BLOCK(ip->i_sb));
+ off = (typ->vt_hdr & VXFS_TYPED_OFFSETMASK);
+
+ if (block < off) {
+ brelse(bp);
+ continue;
+ }
+
+ switch ((u_int32_t)(typ->vt_hdr >> VXFS_TYPED_TYPESHIFT)) {
+ case VXFS_TYPED_INDIRECT:
+ pblock = vxfs_bmap_indir(ip, typ->vt_block,
+ typ->vt_size, block - off);
+ if (pblock == -2)
+ break;
+ goto out;
+ case VXFS_TYPED_DATA:
+ if ((block - off) >= typ->vt_size)
+ break;
+ pblock = (typ->vt_block + block - off);
+ goto out;
+ case VXFS_TYPED_INDIRECT_DEV4:
+ case VXFS_TYPED_DATA_DEV4: {
+ struct vxfs_typed_dev4 *typ4 =
+ (struct vxfs_typed_dev4 *)typ;
+
+ printk(KERN_INFO "\n\nTYPED_DEV4 detected!\n");
+ printk(KERN_INFO "block: %Lu\tsize: %Ld\tdev: %d\n",
+ (unsigned long long) typ4->vd4_block,
+ (unsigned long long) typ4->vd4_size,
+ typ4->vd4_dev);
+ goto fail;
+ }
+ default:
+ BUG();
+ }
+ brelse(bp);
+ }
+
+fail:
+ pblock = 0;
+out:
+ brelse(bp);
+ return (pblock);
+}
+
+/**
+ * vxfs_bmap_typed - bmap for typed extents
+ * @ip: pointer to the inode we do bmap for
+ * @iblock: logical block
+ *
+ * Description:
+ * Performs the bmap operation for typed extents.
+ *
+ * Return Value:
+ * The physical block number on success, else Zero.
+ */
+static daddr_t
+vxfs_bmap_typed(struct inode *ip, long iblock)
+{
+ struct vxfs_inode_info *vip = VXFS_INO(ip);
+ daddr_t pblock = 0;
+ int i;
+
+ for (i = 0; i < VXFS_NTYPED; i++) {
+ struct vxfs_typed *typ = vip->vii_org.typed + i;
+ int64_t off = (typ->vt_hdr & VXFS_TYPED_OFFSETMASK);
+
+#ifdef DIAGNOSTIC
+ vxfs_typdump(typ);
+#endif
+ if (iblock < off)
+ continue;
+ switch ((u_int32_t)(typ->vt_hdr >> VXFS_TYPED_TYPESHIFT)) {
+ case VXFS_TYPED_INDIRECT:
+ pblock = vxfs_bmap_indir(ip, typ->vt_block,
+ typ->vt_size, iblock - off);
+ if (pblock == -2)
+ break;
+ return (pblock);
+ case VXFS_TYPED_DATA:
+ if ((iblock - off) < typ->vt_size)
+ return (typ->vt_block + iblock - off);
+ break;
+ case VXFS_TYPED_INDIRECT_DEV4:
+ case VXFS_TYPED_DATA_DEV4: {
+ struct vxfs_typed_dev4 *typ4 =
+ (struct vxfs_typed_dev4 *)typ;
+
+ printk(KERN_INFO "\n\nTYPED_DEV4 detected!\n");
+ printk(KERN_INFO "block: %Lu\tsize: %Ld\tdev: %d\n",
+ (unsigned long long) typ4->vd4_block,
+ (unsigned long long) typ4->vd4_size,
+ typ4->vd4_dev);
+ return 0;
+ }
+ default:
+ BUG();
+ }
+ }
+
+ return 0;
+}
+
+/**
+ * vxfs_bmap1 - vxfs-internal bmap operation
+ * @ip: pointer to the inode we do bmap for
+ * @iblock: logical block
+ *
+ * Description:
+ * vxfs_bmap1 perfoms a logical to physical block mapping
+ * for vxfs-internal purposes.
+ *
+ * Return Value:
+ * The physical block number on success, else Zero.
+ */
+daddr_t
+vxfs_bmap1(struct inode *ip, long iblock)
+{
+ struct vxfs_inode_info *vip = VXFS_INO(ip);
+
+ if (VXFS_ISEXT4(vip))
+ return vxfs_bmap_ext4(ip, iblock);
+ if (VXFS_ISTYPED(vip))
+ return vxfs_bmap_typed(ip, iblock);
+ if (VXFS_ISNONE(vip))
+ goto unsupp;
+ if (VXFS_ISIMMED(vip))
+ goto unsupp;
+
+ printk(KERN_WARNING "vxfs: inode %ld has no valid orgtype (%x)\n",
+ ip->i_ino, vip->vii_orgtype);
+ BUG();
+
+unsupp:
+ printk(KERN_WARNING "vxfs: inode %ld has an unsupported orgtype (%x)\n",
+ ip->i_ino, vip->vii_orgtype);
+ return 0;
+}