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 #include <linux/mount.h>
  44
  45 #include "vxfs.h"
  46 #include "vxfs_extern.h"
  47 #include "vxfs_dir.h"
  48 #include "vxfs_inode.h"
  49
  50
  51 MODULE_AUTHOR("Christoph Hellwig");
  52 MODULE_DESCRIPTION("Veritas Filesystem (VxFS) driver");
  53 MODULE_LICENSE("Dual BSD/GPL");
  54
  55 MODULE_ALIAS("vxfs"); /* makes mount -t vxfs autoload the module */
  56
  57
  58 static void             vxfs_put_super(struct super_block *);
  59 static int              vxfs_statfs(struct dentry *, struct kstatfs *);
  60 static int              vxfs_remount(struct super_block *, int *, char *);
  61
  62 static const struct super_operations vxfs_super_ops = {
  63         .read_inode =           vxfs_read_inode,
  64         .clear_inode =          vxfs_clear_inode,
  65         .put_super =            vxfs_put_super,
  66         .statfs =               vxfs_statfs,
  67         .remount_fs =           vxfs_remount,
  68 };
  69
  70 /**
  71  * vxfs_put_super - free superblock resources
  72  * @sbp:        VFS superblock.
  73  *
  74  * Description:
  75  *   vxfs_put_super frees all resources allocated for @sbp
  76  *   after the last instance of the filesystem is unmounted.
  77  */
  78
  79 static void
  80 vxfs_put_super(struct super_block *sbp)
  81 {
  82         struct vxfs_sb_info     *infp = VXFS_SBI(sbp);
  83
  84         vxfs_put_fake_inode(infp->vsi_fship);
  85         vxfs_put_fake_inode(infp->vsi_ilist);
  86         vxfs_put_fake_inode(infp->vsi_stilist);
  87
  88         brelse(infp->vsi_bp);
  89         kfree(infp);
  90 }
  91
  92 /**
  93  * vxfs_statfs - get filesystem information
  94  * @dentry:     VFS dentry to locate superblock
  95  * @bufp:       output buffer
  96  *
  97  * Description:
  98  *   vxfs_statfs fills the statfs buffer @bufp with information
  99  *   about the filesystem described by @dentry.
 100  *
 101  * Returns:
 102  *   Zero.
 103  *
 104  * Locking:
 105  *   No locks held.
 106  *
 107  * Notes:
 108  *   This is everything but complete...
 109  */
 110 static int
 111 vxfs_statfs(struct dentry *dentry, struct kstatfs *bufp)
 112 {
 113         struct vxfs_sb_info             *infp = VXFS_SBI(dentry->d_sb);
 114
 115         bufp->f_type = VXFS_SUPER_MAGIC;
 116         bufp->f_bsize = dentry->d_sb->s_blocksize;
 117         bufp->f_blocks = infp->vsi_raw->vs_dsize;
 118         bufp->f_bfree = infp->vsi_raw->vs_free;
 119         bufp->f_bavail = 0;
 120         bufp->f_files = 0;
 121         bufp->f_ffree = infp->vsi_raw->vs_ifree;
 122         bufp->f_namelen = VXFS_NAMELEN;
 123
 124         return 0;
 125 }
 126
 127 static int vxfs_remount(struct super_block *sb, int *flags, char *data)
 128 {
 129         *flags |= MS_RDONLY;
 130         return 0;
 131 }
 132
 133 /**
 134  * vxfs_read_super - read superblock into memory and initalize filesystem
 135  * @sbp:                VFS superblock (to fill)
 136  * @dp:                 fs private mount data
 137  * @silent:             do not complain loudly when sth is wrong
 138  *
 139  * Description:
 140  *   We are called on the first mount of a filesystem to read the
 141  *   superblock into memory and do some basic setup.
 142  *
 143  * Returns:
 144  *   The superblock on success, else %NULL.
 145  *
 146  * Locking:
 147  *   We are under the bkl and @sbp->s_lock.
 148  */
 149 static int vxfs_fill_super(struct super_block *sbp, void *dp, int silent)
 150 {
 151         struct vxfs_sb_info     *infp;
 152         struct vxfs_sb          *rsbp;
 153         struct buffer_head      *bp = NULL;
 154         u_long                  bsize;
 155         struct inode *root;
 156
 157         sbp->s_flags |= MS_RDONLY;
 158
 159         infp = kzalloc(sizeof(*infp), GFP_KERNEL);
 160         if (!infp) {
 161                 printk(KERN_WARNING "vxfs: unable to allocate incore superblock\n");
 162                 return -ENOMEM;
 163         }
 164
 165         bsize = sb_min_blocksize(sbp, BLOCK_SIZE);
 166         if (!bsize) {
 167                 printk(KERN_WARNING "vxfs: unable to set blocksize\n");
 168                 goto out;
 169         }
 170
 171         bp = sb_bread(sbp, 1);
 172         if (!bp || !buffer_mapped(bp)) {
 173                 if (!silent) {
 174                         printk(KERN_WARNING
 175                                 "vxfs: unable to read disk superblock\n");
 176                 }
 177                 goto out;
 178         }
 179
 180         rsbp = (struct vxfs_sb *)bp->b_data;
 181         if (rsbp->vs_magic != VXFS_SUPER_MAGIC) {
 182                 if (!silent)
 183                         printk(KERN_NOTICE "vxfs: WRONG superblock magic\n");
 184                 goto out;
 185         }
 186
 187         if ((rsbp->vs_version < 2 || rsbp->vs_version > 4) && !silent) {
 188                 printk(KERN_NOTICE "vxfs: unsupported VxFS version (%d)\n",
 189                        rsbp->vs_version);
 190                 goto out;
 191         }
 192
 193 #ifdef DIAGNOSTIC
 194         printk(KERN_DEBUG "vxfs: supported VxFS version (%d)\n", rsbp->vs_version);
 195         printk(KERN_DEBUG "vxfs: blocksize: %d\n", rsbp->vs_bsize);
 196 #endif
 197
 198         sbp->s_magic = rsbp->vs_magic;
 199         sbp->s_fs_info = infp;
 200
 201         infp->vsi_raw = rsbp;
 202         infp->vsi_bp = bp;
 203         infp->vsi_oltext = rsbp->vs_oltext[0];
 204         infp->vsi_oltsize = rsbp->vs_oltsize;
 205
 206         if (!sb_set_blocksize(sbp, rsbp->vs_bsize)) {
 207                 printk(KERN_WARNING "vxfs: unable to set final block size\n");
 208                 goto out;
 209         }
 210
 211         if (vxfs_read_olt(sbp, bsize)) {
 212                 printk(KERN_WARNING "vxfs: unable to read olt\n");
 213                 goto out;
 214         }
 215
 216         if (vxfs_read_fshead(sbp)) {
 217                 printk(KERN_WARNING "vxfs: unable to read fshead\n");
 218                 goto out;
 219         }
 220
 221         sbp->s_op = &vxfs_super_ops;
 222         root = iget(sbp, VXFS_ROOT_INO);
 223         sbp->s_root = d_alloc_root(root);
 224         if (!sbp->s_root) {
 225                 iput(root);
 226                 printk(KERN_WARNING "vxfs: unable to get root dentry.\n");
 227                 goto out_free_ilist;
 228         }
 229
 230         return 0;
 231
 232 out_free_ilist:
 233         vxfs_put_fake_inode(infp->vsi_fship);
 234         vxfs_put_fake_inode(infp->vsi_ilist);
 235         vxfs_put_fake_inode(infp->vsi_stilist);
 236 out:
 237         brelse(bp);
 238         kfree(infp);
 239         return -EINVAL;
 240 }
 241
 242 /*
 243  * The usual module blurb.
 244  */
 245 static int vxfs_get_sb(struct file_system_type *fs_type,
 246         int flags, const char *dev_name, void *data, struct vfsmount *mnt)
 247 {
 248         return get_sb_bdev(fs_type, flags, dev_name, data, vxfs_fill_super,
 249                            mnt);
 250 }
 251
 252 static struct file_system_type vxfs_fs_type = {
 253         .owner          = THIS_MODULE,
 254         .name           = "vxfs",
 255         .get_sb         = vxfs_get_sb,
 256         .kill_sb        = kill_block_super,
 257         .fs_flags       = FS_REQUIRES_DEV,
 258 };
 259
 260 static int __init
 261 vxfs_init(void)
 262 {
 263         int rv;
 264
 265         vxfs_inode_cachep = kmem_cache_create("vxfs_inode",
 266                         sizeof(struct vxfs_inode_info), 0,
 267                         SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD, NULL, NULL);
 268         if (!vxfs_inode_cachep)
 269                 return -ENOMEM;
 270         rv = register_filesystem(&vxfs_fs_type);
 271         if (rv < 0)
 272                 kmem_cache_destroy(vxfs_inode_cachep);
 273         return rv;
 274 }
 275
 276 static void __exit
 277 vxfs_cleanup(void)
 278 {
 279         unregister_filesystem(&vxfs_fs_type);
 280         kmem_cache_destroy(vxfs_inode_cachep);
 281 }
 282
 283 module_init(vxfs_init);
 284 module_exit(vxfs_cleanup);