linux/fs/freevxfs/vxfs_super.c
<<
>>
Prefs
   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
  51MODULE_AUTHOR("Christoph Hellwig");
  52MODULE_DESCRIPTION("Veritas Filesystem (VxFS) driver");
  53MODULE_LICENSE("Dual BSD/GPL");
  54
  55MODULE_ALIAS("vxfs"); /* makes mount -t vxfs autoload the module */
  56
  57
  58static void             vxfs_put_super(struct super_block *);
  59static int              vxfs_statfs(struct dentry *, struct kstatfs *);
  60static int              vxfs_remount(struct super_block *, int *, char *);
  61
  62static const struct super_operations vxfs_super_ops = {
  63        .evict_inode =          vxfs_evict_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
  78static void
  79vxfs_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 * @dentry:     VFS dentry to locate superblock
  94 * @bufp:       output buffer
  95 *
  96 * Description:
  97 *   vxfs_statfs fills the statfs buffer @bufp with information
  98 *   about the filesystem described by @dentry.
  99 *
 100 * Returns:
 101 *   Zero.
 102 *
 103 * Locking:
 104 *   No locks held.
 105 *
 106 * Notes:
 107 *   This is everything but complete...
 108 */
 109static int
 110vxfs_statfs(struct dentry *dentry, struct kstatfs *bufp)
 111{
 112        struct vxfs_sb_info             *infp = VXFS_SBI(dentry->d_sb);
 113
 114        bufp->f_type = VXFS_SUPER_MAGIC;
 115        bufp->f_bsize = dentry->d_sb->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
 126static 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 initialize 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 @sbp->s_lock.
 147 */
 148static 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        int ret = -EINVAL;
 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 = vxfs_iget(sbp, VXFS_ROOT_INO);
 223        if (IS_ERR(root)) {
 224                ret = PTR_ERR(root);
 225                goto out;
 226        }
 227        sbp->s_root = d_make_root(root);
 228        if (!sbp->s_root) {
 229                printk(KERN_WARNING "vxfs: unable to get root dentry.\n");
 230                goto out_free_ilist;
 231        }
 232
 233        return 0;
 234        
 235out_free_ilist:
 236        vxfs_put_fake_inode(infp->vsi_fship);
 237        vxfs_put_fake_inode(infp->vsi_ilist);
 238        vxfs_put_fake_inode(infp->vsi_stilist);
 239out:
 240        brelse(bp);
 241        kfree(infp);
 242        return ret;
 243}
 244
 245/*
 246 * The usual module blurb.
 247 */
 248static struct dentry *vxfs_mount(struct file_system_type *fs_type,
 249        int flags, const char *dev_name, void *data)
 250{
 251        return mount_bdev(fs_type, flags, dev_name, data, vxfs_fill_super);
 252}
 253
 254static struct file_system_type vxfs_fs_type = {
 255        .owner          = THIS_MODULE,
 256        .name           = "vxfs",
 257        .mount          = vxfs_mount,
 258        .kill_sb        = kill_block_super,
 259        .fs_flags       = FS_REQUIRES_DEV,
 260};
 261
 262static int __init
 263vxfs_init(void)
 264{
 265        int rv;
 266
 267        vxfs_inode_cachep = kmem_cache_create("vxfs_inode",
 268                        sizeof(struct vxfs_inode_info), 0,
 269                        SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD, NULL);
 270        if (!vxfs_inode_cachep)
 271                return -ENOMEM;
 272        rv = register_filesystem(&vxfs_fs_type);
 273        if (rv < 0)
 274                kmem_cache_destroy(vxfs_inode_cachep);
 275        return rv;
 276}
 277
 278static void __exit
 279vxfs_cleanup(void)
 280{
 281        unregister_filesystem(&vxfs_fs_type);
 282        /*
 283         * Make sure all delayed rcu free inodes are flushed before we
 284         * destroy cache.
 285         */
 286        rcu_barrier();
 287        kmem_cache_destroy(vxfs_inode_cachep);
 288}
 289
 290module_init(vxfs_init);
 291module_exit(vxfs_cleanup);
 292
lxr.linux.no kindly hosted by Redpill Linpro AS, provider of Linux consulting and operations services since 1995.