linux/fs/freevxfs/vxfs_super.c

364 lines
8.8 KiB
C

/*
* Copyright (c) 2000-2001 Christoph Hellwig.
* Copyright (c) 2016 Krzysztof Blaszkowski
* 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 - superblock related routines.
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/blkdev.h>
#include <linux/fs.h>
#include <linux/buffer_head.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/stat.h>
#include <linux/vfs.h>
#include <linux/mount.h>
#include "vxfs.h"
#include "vxfs_extern.h"
#include "vxfs_dir.h"
#include "vxfs_inode.h"
MODULE_AUTHOR("Christoph Hellwig, Krzysztof Blaszkowski");
MODULE_DESCRIPTION("Veritas Filesystem (VxFS) driver");
MODULE_LICENSE("Dual BSD/GPL");
static struct kmem_cache *vxfs_inode_cachep;
/**
* vxfs_put_super - free superblock resources
* @sbp: VFS superblock.
*
* Description:
* vxfs_put_super frees all resources allocated for @sbp
* after the last instance of the filesystem is unmounted.
*/
static void
vxfs_put_super(struct super_block *sbp)
{
struct vxfs_sb_info *infp = VXFS_SBI(sbp);
iput(infp->vsi_fship);
iput(infp->vsi_ilist);
iput(infp->vsi_stilist);
brelse(infp->vsi_bp);
kfree(infp);
}
/**
* vxfs_statfs - get filesystem information
* @dentry: VFS dentry to locate superblock
* @bufp: output buffer
*
* Description:
* vxfs_statfs fills the statfs buffer @bufp with information
* about the filesystem described by @dentry.
*
* Returns:
* Zero.
*
* Locking:
* No locks held.
*
* Notes:
* This is everything but complete...
*/
static int
vxfs_statfs(struct dentry *dentry, struct kstatfs *bufp)
{
struct vxfs_sb_info *infp = VXFS_SBI(dentry->d_sb);
struct vxfs_sb *raw_sb = infp->vsi_raw;
bufp->f_type = VXFS_SUPER_MAGIC;
bufp->f_bsize = dentry->d_sb->s_blocksize;
bufp->f_blocks = fs32_to_cpu(infp, raw_sb->vs_dsize);
bufp->f_bfree = fs32_to_cpu(infp, raw_sb->vs_free);
bufp->f_bavail = 0;
bufp->f_files = 0;
bufp->f_ffree = fs32_to_cpu(infp, raw_sb->vs_ifree);
bufp->f_namelen = VXFS_NAMELEN;
return 0;
}
static int vxfs_remount(struct super_block *sb, int *flags, char *data)
{
sync_filesystem(sb);
*flags |= SB_RDONLY;
return 0;
}
static struct inode *vxfs_alloc_inode(struct super_block *sb)
{
struct vxfs_inode_info *vi;
vi = kmem_cache_alloc(vxfs_inode_cachep, GFP_KERNEL);
if (!vi)
return NULL;
inode_init_once(&vi->vfs_inode);
return &vi->vfs_inode;
}
static void vxfs_i_callback(struct rcu_head *head)
{
struct inode *inode = container_of(head, struct inode, i_rcu);
kmem_cache_free(vxfs_inode_cachep, VXFS_INO(inode));
}
static void vxfs_destroy_inode(struct inode *inode)
{
call_rcu(&inode->i_rcu, vxfs_i_callback);
}
static const struct super_operations vxfs_super_ops = {
.alloc_inode = vxfs_alloc_inode,
.destroy_inode = vxfs_destroy_inode,
.evict_inode = vxfs_evict_inode,
.put_super = vxfs_put_super,
.statfs = vxfs_statfs,
.remount_fs = vxfs_remount,
};
static int vxfs_try_sb_magic(struct super_block *sbp, int silent,
unsigned blk, __fs32 magic)
{
struct buffer_head *bp;
struct vxfs_sb *rsbp;
struct vxfs_sb_info *infp = VXFS_SBI(sbp);
int rc = -ENOMEM;
bp = sb_bread(sbp, blk);
do {
if (!bp || !buffer_mapped(bp)) {
if (!silent) {
printk(KERN_WARNING
"vxfs: unable to read disk superblock at %u\n",
blk);
}
break;
}
rc = -EINVAL;
rsbp = (struct vxfs_sb *)bp->b_data;
if (rsbp->vs_magic != magic) {
if (!silent)
printk(KERN_NOTICE
"vxfs: WRONG superblock magic %08x at %u\n",
rsbp->vs_magic, blk);
break;
}
rc = 0;
infp->vsi_raw = rsbp;
infp->vsi_bp = bp;
} while (0);
if (rc) {
infp->vsi_raw = NULL;
infp->vsi_bp = NULL;
brelse(bp);
}
return rc;
}
/**
* vxfs_read_super - read superblock into memory and initialize filesystem
* @sbp: VFS superblock (to fill)
* @dp: fs private mount data
* @silent: do not complain loudly when sth is wrong
*
* Description:
* We are called on the first mount of a filesystem to read the
* superblock into memory and do some basic setup.
*
* Returns:
* The superblock on success, else %NULL.
*
* Locking:
* We are under @sbp->s_lock.
*/
static int vxfs_fill_super(struct super_block *sbp, void *dp, int silent)
{
struct vxfs_sb_info *infp;
struct vxfs_sb *rsbp;
u_long bsize;
struct inode *root;
int ret = -EINVAL;
u32 j;
sbp->s_flags |= SB_RDONLY;
infp = kzalloc(sizeof(*infp), GFP_KERNEL);
if (!infp) {
printk(KERN_WARNING "vxfs: unable to allocate incore superblock\n");
return -ENOMEM;
}
bsize = sb_min_blocksize(sbp, BLOCK_SIZE);
if (!bsize) {
printk(KERN_WARNING "vxfs: unable to set blocksize\n");
goto out;
}
sbp->s_op = &vxfs_super_ops;
sbp->s_fs_info = infp;
if (!vxfs_try_sb_magic(sbp, silent, 1,
(__force __fs32)cpu_to_le32(VXFS_SUPER_MAGIC))) {
/* Unixware, x86 */
infp->byte_order = VXFS_BO_LE;
} else if (!vxfs_try_sb_magic(sbp, silent, 8,
(__force __fs32)cpu_to_be32(VXFS_SUPER_MAGIC))) {
/* HP-UX, parisc */
infp->byte_order = VXFS_BO_BE;
} else {
if (!silent)
printk(KERN_NOTICE "vxfs: can't find superblock.\n");
goto out;
}
rsbp = infp->vsi_raw;
j = fs32_to_cpu(infp, rsbp->vs_version);
if ((j < 2 || j > 4) && !silent) {
printk(KERN_NOTICE "vxfs: unsupported VxFS version (%d)\n", j);
goto out;
}
#ifdef DIAGNOSTIC
printk(KERN_DEBUG "vxfs: supported VxFS version (%d)\n", j);
printk(KERN_DEBUG "vxfs: blocksize: %d\n",
fs32_to_cpu(infp, rsbp->vs_bsize));
#endif
sbp->s_magic = fs32_to_cpu(infp, rsbp->vs_magic);
infp->vsi_oltext = fs32_to_cpu(infp, rsbp->vs_oltext[0]);
infp->vsi_oltsize = fs32_to_cpu(infp, rsbp->vs_oltsize);
j = fs32_to_cpu(infp, rsbp->vs_bsize);
if (!sb_set_blocksize(sbp, j)) {
printk(KERN_WARNING "vxfs: unable to set final block size\n");
goto out;
}
if (vxfs_read_olt(sbp, bsize)) {
printk(KERN_WARNING "vxfs: unable to read olt\n");
goto out;
}
if (vxfs_read_fshead(sbp)) {
printk(KERN_WARNING "vxfs: unable to read fshead\n");
goto out;
}
root = vxfs_iget(sbp, VXFS_ROOT_INO);
if (IS_ERR(root)) {
ret = PTR_ERR(root);
goto out;
}
sbp->s_root = d_make_root(root);
if (!sbp->s_root) {
printk(KERN_WARNING "vxfs: unable to get root dentry.\n");
goto out_free_ilist;
}
return 0;
out_free_ilist:
iput(infp->vsi_fship);
iput(infp->vsi_ilist);
iput(infp->vsi_stilist);
out:
brelse(infp->vsi_bp);
kfree(infp);
return ret;
}
/*
* The usual module blurb.
*/
static struct dentry *vxfs_mount(struct file_system_type *fs_type,
int flags, const char *dev_name, void *data)
{
return mount_bdev(fs_type, flags, dev_name, data, vxfs_fill_super);
}
static struct file_system_type vxfs_fs_type = {
.owner = THIS_MODULE,
.name = "vxfs",
.mount = vxfs_mount,
.kill_sb = kill_block_super,
.fs_flags = FS_REQUIRES_DEV,
};
MODULE_ALIAS_FS("vxfs"); /* makes mount -t vxfs autoload the module */
MODULE_ALIAS("vxfs");
static int __init
vxfs_init(void)
{
int rv;
vxfs_inode_cachep = kmem_cache_create_usercopy("vxfs_inode",
sizeof(struct vxfs_inode_info), 0,
SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD,
offsetof(struct vxfs_inode_info, vii_immed.vi_immed),
sizeof_field(struct vxfs_inode_info,
vii_immed.vi_immed),
NULL);
if (!vxfs_inode_cachep)
return -ENOMEM;
rv = register_filesystem(&vxfs_fs_type);
if (rv < 0)
kmem_cache_destroy(vxfs_inode_cachep);
return rv;
}
static void __exit
vxfs_cleanup(void)
{
unregister_filesystem(&vxfs_fs_type);
/*
* Make sure all delayed rcu free inodes are flushed before we
* destroy cache.
*/
rcu_barrier();
kmem_cache_destroy(vxfs_inode_cachep);
}
module_init(vxfs_init);
module_exit(vxfs_cleanup);