| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (c) 2000-2001 Christoph Hellwig. |
| 3 | * All rights reserved. |
| 4 | * |
| 5 | * Redistribution and use in source and binary forms, with or without |
| 6 | * modification, are permitted provided that the following conditions |
| 7 | * are met: |
| 8 | * 1. Redistributions of source code must retain the above copyright |
| 9 | * notice, this list of conditions, and the following disclaimer, |
| 10 | * without modification. |
| 11 | * 2. The name of the author may not be used to endorse or promote products |
| 12 | * derived from this software without specific prior written permission. |
| 13 | * |
| 14 | * Alternatively, this software may be distributed under the terms of the |
| 15 | * GNU General Public License ("GPL"). |
| 16 | * |
| 17 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND |
| 18 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| 19 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| 20 | * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR |
| 21 | * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| 22 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| 23 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| 24 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| 25 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| 26 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| 27 | * SUCH DAMAGE. |
| 28 | */ |
| 29 | |
| 30 | /* |
| 31 | * Veritas filesystem driver - object location table support. |
| 32 | */ |
| 33 | #include <linux/fs.h> |
| 34 | #include <linux/buffer_head.h> |
| 35 | #include <linux/kernel.h> |
| 36 | |
| 37 | #include "vxfs.h" |
| 38 | #include "vxfs_olt.h" |
| 39 | |
| 40 | |
| 41 | static __inline__ void |
| 42 | vxfs_get_fshead(struct vxfs_oltfshead *fshp, struct vxfs_sb_info *infp) |
| 43 | { |
| 44 | if (infp->vsi_fshino) |
| 45 | BUG(); |
| 46 | infp->vsi_fshino = fshp->olt_fsino[0]; |
| 47 | } |
| 48 | |
| 49 | static __inline__ void |
| 50 | vxfs_get_ilist(struct vxfs_oltilist *ilistp, struct vxfs_sb_info *infp) |
| 51 | { |
| 52 | if (infp->vsi_iext) |
| 53 | BUG(); |
| 54 | infp->vsi_iext = ilistp->olt_iext[0]; |
| 55 | } |
| 56 | |
| 57 | static __inline__ u_long |
| 58 | vxfs_oblock(struct super_block *sbp, daddr_t block, u_long bsize) |
| 59 | { |
| 60 | if (sbp->s_blocksize % bsize) |
| 61 | BUG(); |
| 62 | return (block * (sbp->s_blocksize / bsize)); |
| 63 | } |
| 64 | |
| 65 | |
| 66 | /** |
| 67 | * vxfs_read_olt - read olt |
| 68 | * @sbp: superblock of the filesystem |
| 69 | * @bsize: blocksize of the filesystem |
| 70 | * |
| 71 | * Description: |
| 72 | * vxfs_read_olt reads the olt of the filesystem described by @sbp |
| 73 | * into main memory and does some basic setup. |
| 74 | * |
| 75 | * Returns: |
| 76 | * Zero on success, else a negative error code. |
| 77 | */ |
| 78 | int |
| 79 | vxfs_read_olt(struct super_block *sbp, u_long bsize) |
| 80 | { |
| 81 | struct vxfs_sb_info *infp = VXFS_SBI(sbp); |
| 82 | struct buffer_head *bp; |
| 83 | struct vxfs_olt *op; |
| 84 | char *oaddr, *eaddr; |
| 85 | |
| 86 | |
| 87 | bp = sb_bread(sbp, vxfs_oblock(sbp, infp->vsi_oltext, bsize)); |
| 88 | if (!bp || !bp->b_data) |
| 89 | goto fail; |
| 90 | |
| 91 | op = (struct vxfs_olt *)bp->b_data; |
| 92 | if (op->olt_magic != VXFS_OLT_MAGIC) { |
| 93 | printk(KERN_NOTICE "vxfs: ivalid olt magic number\n"); |
| 94 | goto fail; |
| 95 | } |
| 96 | |
| 97 | /* |
| 98 | * It is in theory possible that vsi_oltsize is > 1. |
| 99 | * I've not seen any such filesystem yet and I'm lazy.. --hch |
| 100 | */ |
| 101 | if (infp->vsi_oltsize > 1) { |
| 102 | printk(KERN_NOTICE "vxfs: oltsize > 1 detected.\n"); |
| 103 | printk(KERN_NOTICE "vxfs: please notify hch@infradead.org\n"); |
| 104 | goto fail; |
| 105 | } |
| 106 | |
| 107 | oaddr = (char *)bp->b_data + op->olt_size; |
| 108 | eaddr = (char *)bp->b_data + (infp->vsi_oltsize * sbp->s_blocksize); |
| 109 | |
| 110 | while (oaddr < eaddr) { |
| 111 | struct vxfs_oltcommon *ocp = |
| 112 | (struct vxfs_oltcommon *)oaddr; |
| 113 | |
| 114 | switch (ocp->olt_type) { |
| 115 | case VXFS_OLT_FSHEAD: |
| 116 | vxfs_get_fshead((struct vxfs_oltfshead *)oaddr, infp); |
| 117 | break; |
| 118 | case VXFS_OLT_ILIST: |
| 119 | vxfs_get_ilist((struct vxfs_oltilist *)oaddr, infp); |
| 120 | break; |
| 121 | } |
| 122 | |
| 123 | oaddr += ocp->olt_size; |
| 124 | } |
| 125 | |
| 126 | brelse(bp); |
| 127 | return 0; |
| 128 | |
| 129 | fail: |
| 130 | brelse(bp); |
| 131 | return -EINVAL; |
| 132 | } |