fs/freevxfs/vxfs_super.c

   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 - superblock related routines.
  32  */
  33 #include <linux/init.h>
  34 #include <linux/module.h>
  35
  36 #include <linux/blkdev.h>
  37 #include <linux/fs.h>
  38 #include <linux/buffer_head.h>
  39 #include <linux/kernel.h>
  40 #include <linux/slab.h>
  41 #include <linux/stat.h>
  42 #include <linux/vfs.h>
  43
  44 #include "vxfs.h"
  45 #include "vxfs_extern.h"
  46 #include "vxfs_dir.h"
  47 #include "vxfs_inode.h"
  48
  49
  50 MODULE_AUTHOR("Christoph Hellwig");
  51 MODULE_DESCRIPTION("Veritas Filesystem (VxFS) driver");
  52 MODULE_LICENSE("Dual BSD/GPL");
  53
  54 MODULE_ALIAS("vxfs"); /* makes mount -t vxfs autoload the module */
  55
  56
  57 static void             vxfs_put_super(struct super_block *);
  58 static int              vxfs_statfs(struct super_block *, struct kstatfs *);
  59 static int              vxfs_remount(struct super_block *, int *, char *);
  60
  61 static struct super_operations vxfs_super_ops = {
  62         .read_inode =           vxfs_read_inode,
  63         .clear_inode =          vxfs_clear_inode,
  64         .put_super =            vxfs_put_super,
  65         .statfs =               vxfs_statfs,
  66         .remount_fs =           vxfs_remount,
  67 };
  68
  69 /**
  70  * vxfs_put_super - free superblock resources
  71  * @sbp:        VFS superblock.
  72  *
  73  * Description:
  74  *   vxfs_put_super frees all resources allocated for @sbp
  75  *   after the last instance of the filesystem is unmounted.
  76  */
  77
  78 static void
  79 vxfs_put_super(struct super_block *sbp)
  80 {
  81         struct vxfs_sb_info     *infp = VXFS_SBI(sbp);
  82
  83         vxfs_put_fake_inode(infp->vsi_fship);
  84         vxfs_put_fake_inode(infp->vsi_ilist);
  85         vxfs_put_fake_inode(infp->vsi_stilist);
  86
  87         brelse(infp->vsi_bp);
  88         kfree(infp);
  89 }
  90
  91 /**
  92  * vxfs_statfs - get filesystem information
  93  * @sbp:        VFS superblock
  94  * @bufp:       output buffer
  95  *
  96  * Description:
  97  *   vxfs_statfs fills the statfs buffer @bufp with information
  98  *   about the filesystem described by @sbp.
  99  *
 100  * Returns:
 101  *   Zero.
 102  *
 103  * Locking:
 104  *   No locks held.
 105  *
 106  * Notes:
 107  *   This is everything but complete...
 108  */
 109 static int
 110 vxfs_statfs(struct super_block *sbp, struct kstatfs *bufp)
 111 {
 112         struct vxfs_sb_info             *infp = VXFS_SBI(sbp);
 113
 114         bufp->f_type = VXFS_SUPER_MAGIC;
 115         bufp->f_bsize = sbp->s_blocksize;
 116         bufp->f_blocks = infp->vsi_raw->vs_dsize;
 117         bufp->f_bfree = infp->vsi_raw->vs_free;
 118         bufp->f_bavail = 0;
 119         bufp->f_files = 0;
 120         bufp->f_ffree = infp->vsi_raw->vs_ifree;
 121         bufp->f_namelen = VXFS_NAMELEN;
 122
 123         return 0;
 124 }
 125
 126 static int vxfs_remount(struct super_block *sb, int *flags, char *data)
 127 {
 128         *flags |= MS_RDONLY;
 129         return 0;
 130 }
 131
 132 /**
 133  * vxfs_read_super - read superblock into memory and initalize filesystem
 134  * @sbp:                VFS superblock (to fill)
 135  * @dp:                 fs private mount data
 136  * @silent:             do not complain loudly when sth is wrong
 137  *
 138  * Description:
 139  *   We are called on the first mount of a filesystem to read the
 140  *   superblock into memory and do some basic setup.
 141  *
 142  * Returns:
 143  *   The superblock on success, else %NULL.
 144  *
 145  * Locking:
 146  *   We are under the bkl and @sbp->s_lock.
 147  */
 148 static int vxfs_fill_super(struct super_block *sbp, void *dp, int silent)
 149 {
 150         struct vxfs_sb_info     *infp;
 151         struct vxfs_sb          *rsbp;
 152         struct buffer_head      *bp = NULL;
 153         u_long                  bsize;
 154         struct inode *root;
 155
 156         sbp->s_flags |= MS_RDONLY;
 157
 158         infp = kzalloc(sizeof(*infp), GFP_KERNEL);
 159         if (!infp) {
 160                 printk(KERN_WARNING "vxfs: unable to allocate incore superblock\n");
 161                 return -ENOMEM;
 162         }
 163
 164         bsize = sb_min_blocksize(sbp, BLOCK_SIZE);
 165         if (!bsize) {
 166                 printk(KERN_WARNING "vxfs: unable to set blocksize\n");
 167                 goto out;
 168         }
 169
 170         bp = sb_bread(sbp, 1);
 171         if (!bp || !buffer_mapped(bp)) {
 172                 if (!silent) {
 173                         printk(KERN_WARNING
 174                                 "vxfs: unable to read disk superblock\n");
 175                 }
 176                 goto out;
 177         }
 178
 179         rsbp = (struct vxfs_sb *)bp->b_data;
 180         if (rsbp->vs_magic != VXFS_SUPER_MAGIC) {
 181                 if (!silent)
 182                         printk(KERN_NOTICE "vxfs: WRONG superblock magic\n");
 183                 goto out;
 184         }
 185
 186         if ((rsbp->vs_version < 2 || rsbp->vs_version > 4) && !silent) {
 187                 printk(KERN_NOTICE "vxfs: unsupported VxFS version (%d)\n",
 188                        rsbp->vs_version);
 189                 goto out;
 190         }
 191
 192 #ifdef DIAGNOSTIC
 193         printk(KERN_DEBUG "vxfs: supported VxFS version (%d)\n", rsbp->vs_version);
 194         printk(KERN_DEBUG "vxfs: blocksize: %d\n", rsbp->vs_bsize);
 195 #endif
 196
 197         sbp->s_magic = rsbp->vs_magic;
 198         sbp->s_fs_info = infp;
 199
 200         infp->vsi_raw = rsbp;
 201         infp->vsi_bp = bp;
 202         infp->vsi_oltext = rsbp->vs_oltext[0];
 203         infp->vsi_oltsize = rsbp->vs_oltsize;
 204
 205         if (!sb_set_blocksize(sbp, rsbp->vs_bsize)) {
 206                 printk(KERN_WARNING "vxfs: unable to set final block size\n");
 207                 goto out;
 208         }
 209
 210         if (vxfs_read_olt(sbp, bsize)) {
 211                 printk(KERN_WARNING "vxfs: unable to read olt\n");
 212                 goto out;
 213         }
 214
 215         if (vxfs_read_fshead(sbp)) {
 216                 printk(KERN_WARNING "vxfs: unable to read fshead\n");
 217                 goto out;
 218         }
 219
 220         sbp->s_op = &vxfs_super_ops;
 221         root = iget(sbp, VXFS_ROOT_INO);
 222         sbp->s_root = d_alloc_root(root);
 223         if (!sbp->s_root) {
 224                 iput(root);
 225                 printk(KERN_WARNING "vxfs: unable to get root dentry.\n");
 226                 goto out_free_ilist;
 227         }
 228
 229         return 0;
 230
 231 out_free_ilist:
 232         vxfs_put_fake_inode(infp->vsi_fship);
 233         vxfs_put_fake_inode(infp->vsi_ilist);
 234         vxfs_put_fake_inode(infp->vsi_stilist);
 235 out:
 236         brelse(bp);
 237         kfree(infp);
 238         return -EINVAL;
 239 }
 240
 241 /*
 242  * The usual module blurb.
 243  */
 244 static struct super_block *vxfs_get_sb(struct file_system_type *fs_type,
 245         int flags, const char *dev_name, void *data)
 246 {
 247         return get_sb_bdev(fs_type, flags, dev_name, data, vxfs_fill_super);
 248 }
 249
 250 static struct file_system_type vxfs_fs_type = {
 251         .owner          = THIS_MODULE,
 252         .name           = "vxfs",
 253         .get_sb         = vxfs_get_sb,
 254         .kill_sb        = kill_block_super,
 255         .fs_flags       = FS_REQUIRES_DEV,
 256 };
 257
 258 static int __init
 259 vxfs_init(void)
 260 {
 261         vxfs_inode_cachep = kmem_cache_create("vxfs_inode",
 262                         sizeof(struct vxfs_inode_info), 0,
 263                         SLAB_RECLAIM_ACCOUNT, NULL, NULL);
 264         if (vxfs_inode_cachep)
 265                 return register_filesystem(&vxfs_fs_type);
 266         return -ENOMEM;
 267 }
 268
 269 static void __exit
 270 vxfs_cleanup(void)
 271 {
 272         unregister_filesystem(&vxfs_fs_type);
 273         kmem_cache_destroy(vxfs_inode_cachep);
 274 }
 275
 276 module_init(vxfs_init);
 277 module_exit(vxfs_cleanup);