Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / fs / freevxfs / vxfs_bmap.c
diff --git a/kernel/fs/freevxfs/vxfs_bmap.c b/kernel/fs/freevxfs/vxfs_bmap.c
new file mode 100644 (file)
index 0000000..f86fd3c
--- /dev/null
@@ -0,0 +1,281 @@
+/*
+ * 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;
+}