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author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /fs/freevxfs/vxfs_bmap.c | |
download | lwn-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz lwn-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.zip |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'fs/freevxfs/vxfs_bmap.c')
-rw-r--r-- | fs/freevxfs/vxfs_bmap.c | 280 |
1 files changed, 280 insertions, 0 deletions
diff --git a/fs/freevxfs/vxfs_bmap.c b/fs/freevxfs/vxfs_bmap.c new file mode 100644 index 000000000000..bc4b57da306a --- /dev/null +++ b/fs/freevxfs/vxfs_bmap.c @@ -0,0 +1,280 @@ +/* + * 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" + + +#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 to 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 (!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; +} |