/*
* JFFS2 -- Journalling Flash File System, Version 2.
*
* Copyright (C) 2001-2003 Red Hat, Inc.
*
* Created by David Woodhouse <dwmw2@infradead.org>
*
* For licensing information, see the file 'LICENCE' in this directory.
*
* $Id: super.c,v 1.106 2005/05/18 11:37:25 dedekind Exp $
*
*/
#include <linux/config.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/list.h>
#include <linux/fs.h>
#include <linux/mount.h>
#include <linux/jffs2.h>
#include <linux/pagemap.h>
#include <linux/mtd/mtd.h>
#include <linux/ctype.h>
#include <linux/namei.h>
#include "compr.h"
#include "nodelist.h"
static void jffs2_put_super(struct super_block *);
static kmem_cache_t *jffs2_inode_cachep;
static struct inode *jffs2_alloc_inode(struct super_block *sb)
{
struct jffs2_inode_info *ei;
ei = (struct jffs2_inode_info *)kmem_cache_alloc(jffs2_inode_cachep, SLAB_KERNEL);
if (!ei)
return NULL;
return &ei->vfs_inode;
}
static void jffs2_destroy_inode(struct inode *inode)
{
kmem_cache_free(jffs2_inode_cachep, JFFS2_INODE_INFO(inode));
}
static void jffs2_i_init_once(void * foo, kmem_cache_t * cachep, unsigned long flags)
{
struct jffs2_inode_info *ei = (struct jffs2_inode_info *) foo;
if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) ==
SLAB_CTOR_CONSTRUCTOR) {
init_MUTEX_LOCKED(&ei->sem);
inode_init_once(&ei->vfs_inode);
}
}
static int jffs2_sync_fs(struct super_block *sb, int wait)
{
struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);
down(&c->alloc_sem);
jffs2_flush_wbuf_pad(c);
up(&c->alloc_sem);
return 0;
}
static struct super_operations jffs2_super_operations =
{
.alloc_inode = jffs2_alloc_inode,
.destroy_inode =jffs2_destroy_inode,
.read_inode = jffs2_read_inode,
.put_super = jffs2_put_super,
.write_super = jffs2_write_super,
.statfs = jffs2_statfs,
.remount_fs = jffs2_remount_fs,
.clear_inode = jffs2_clear_inode,
.dirty_inode = jffs2_dirty_inode,
.sync_fs = jffs2_sync_fs,
};
static int jffs2_sb_compare(struct super_block *sb, void *data)
{
struct jffs2_sb_info *p = data;
struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);
/* The superblocks are considered to be equivalent if the underlying MTD
device is the same one */
if (c->mtd == p->mtd) {
D1(printk(KERN_DEBUG "jffs2_sb_compare: match on device %d (\"%s\")\n", p->mtd->index, p->mtd->name));
return 1;
} else {
D1(printk(KERN_DEBUG "jffs2_sb_compare: No match, device %d (\"%s\"), device %d (\"%s\")\n",
c->mtd->index, c->mtd->name, p->mtd->index, p->mtd->name));
return 0;
}
}
static int jffs2_sb_set(struct super_block *sb, void *data)
{
struct jffs2_sb_info *p = data;
/* For persistence of NFS exports etc. we use the same s_dev
each time we mount the device, don't just use an anonymous
device */
sb->s_fs_info = p;
p->os_priv = sb;
sb->s_dev = MKDEV(MTD_BLOCK_MAJOR, p->mtd->index);
return 0;
}
static struct super_block *jffs2_get_sb_mtd(struct file_system_type *fs_type,
int flags, const char *dev_name,
void *data, struct mtd_info *mtd)
{
struct super_block *sb;
struct jffs2_sb_info *c;
int ret;
c = kmalloc(sizeof(*c), GFP_KERNEL);
if (!c)
return ERR_PTR(-ENOMEM);
memset(c, 0, sizeof(*c));
c->mtd = mtd;
sb = sget(fs_type, jffs2_sb_compare, jffs2_sb_set, c);
if (IS_ERR(sb))
goto out_put;
if (sb->s_root) {
/* New mountpoint for JFFS2 which is already mounted */
D1(printk(KERN_DEBUG "jffs2_get_sb_mtd(): Device %d (\"%s\") is already mounted\n",
mtd->index, mtd->name));
goto out_put;
}
D1(printk(KERN_DEBUG "jffs2_get_sb_mtd(): New superblock for device %d (\"%s\")\n",
mtd->index, mtd->name));
sb->s_op = &jffs2_super_operations;
sb->s_flags = flags | MS_NOATIME;
ret = jffs2_do_fill_super(sb, data, (flags&MS_VERBOSE)?1:0);
if (ret) {
/* Failure case... */
up_write(&sb->s_umount);
deactivate_super(sb);
return ERR_PTR(ret);
}
sb->s_flags |= MS_ACTIVE;
return sb;
out_put:
kfree(c);
put_mtd_device(mtd);
return sb;
}
static struct super_block *jffs2_get_sb_mtdnr(struct file_system_type *fs_type,
int flags, const char *dev_name,
void *data, int mtdnr)
{
struct mtd_info *mtd;
mtd = get_mtd_device(NULL, mtdnr);
if (!mtd) {
D1(printk(KERN_DEBUG "jffs2: MTD device #%u doesn't appear to exist\n", mtdnr));
return ERR_PTR(-EINVAL);
}
return jffs2_get_sb_mtd(fs_type, flags, dev_name, data, mtd);
}
static struct super_block *jffs2_get_sb(struct file_system_type *fs_type,
int flags, const char *dev_name,
void *data)
{
int err;
struct nameidata nd;
int mtdnr;
if (!dev_name)
return ERR_PTR(-EINVAL);
D1(printk(KERN_DEBUG "jffs2_get_sb(): dev_name \"%s\"\n", dev_name));
/* The preferred way of mounting in future; especially when
CONFIG_BLK_DEV is implemented - we specify the underlying
MTD device by number or by name, so that we don't require
block device support to be present in the kernel. */
/* FIXME: How to do the root fs this way? */
if (dev_name[0] == 'm' && dev_name[1] == 't' && dev_name[2] == 'd') {
/* Probably mounting without the blkdev crap */
if (dev_name[3] == ':') {
struct mtd_info *mtd;
/* Mount by MTD device name */
D1(printk(KERN_DEBUG "jffs2_get_sb(): mtd:%%s, name \"%s\"\n", dev_name+4));
for (mtdnr = 0; mtdnr < MAX_MTD_DEVICES; mtdnr++) {
mtd = get_mtd_device(NULL, mtdnr);
if (mtd) {
if (!strcmp(mtd->name, dev_name+4))
return jffs2_get_sb_mtd(fs_type, flags, dev_name, data, mtd);
put_mtd_device(mtd);
}
}
printk(KERN_NOTICE "jffs2_get_sb(): MTD device with name \"%s\" not found.\n", dev_name+4);
} else if (isdigit(dev_name[3])) {
/* Mount by MTD device number name */
char *endptr;
mtdnr = simple_strtoul(dev_name+3, &endptr, 0);
if (!*endptr) {
/* It was a valid number */
D1(printk(KERN_DEBUG "jffs2_get_sb(): mtd%%d, mtdnr %d\n", mtdnr));
return jffs2_get_sb_mtdnr(fs_type, flags, dev_name, data, mtdnr);
}
}
}
/* Try the old way - the hack where we allowed users to mount
/dev/mtdblock$(n) but didn't actually _use_ the blkdev */
err = path_lookup(dev_name, LOOKUP_FOLLOW, &nd);
D1(printk(KERN_DEBUG "jffs2_get_sb(): path_lookup() returned %d, inode %p\n",
err, nd.dentry->d_inode));
if (err)
return ERR_PTR(err);
err = -EINVAL;
if (!S_ISBLK(nd.dentry->d_inode->i_mode))
goto out;
if (nd.mnt->mnt_flags & MNT_NODEV) {
err = -EACCES;
goto out;
}
if (imajor(nd.dentry->d_inode) != MTD_BLOCK_MAJOR) {
if (!(flags & MS_VERBOSE)) /* Yes I mean this. Strangely */
printk(KERN_NOTICE "Attempt to mount non-MTD device \"%s\" as JFFS2\n",
dev_name);
goto out;
}
mtdnr = iminor(nd.dentry->d_inode);
path_release(&nd);
return jffs2_get_sb_mtdnr(fs_type, flags, dev_name, data, mtdnr);
out:
path_release(&nd);
return ERR_PTR(err);
}
static void jffs2_put_super (struct super_block *sb)
{
struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);
D2(printk(KERN_DEBUG "jffs2: jffs2_put_super()\n"));
down(&c->alloc_sem);
jffs2_flush_wbuf_pad(c);
up(&c->alloc_sem);
jffs2_free_ino_caches(c);
jffs2_free_raw_node_refs(c);
if (c->mtd->flags & MTD_NO_VIRTBLOCKS)
vfree(c->blocks);
else
kfree(c->blocks);
jffs2_flash_cleanup(c);
kfree(c->inocache_list);
if (c->mtd->sync)
c->mtd->sync(c->mtd);
D1(printk(KERN_DEBUG "jffs2_put_super returning\n"));
}
static void jffs2_kill_sb(struct super_block *sb)
{
struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);
if (!(sb->s_flags & MS_RDONLY))
jffs2_stop_garbage_collect_thread(c);
generic_shutdown_super(sb);
put_mtd_device(c->mtd);
kfree(c);
}
static struct file_system_type jffs2_fs_type = {
.owner = THIS_MODULE,
.name = "jffs2",
.get_sb = jffs2_get_sb,
.kill_sb = jffs2_kill_sb,
};
static int __init init_jffs2_fs(void)
{
int ret;
printk(KERN_INFO "JFFS2 version 2.2."
#ifdef CONFIG_JFFS2_FS_WRITEBUFFER
" (NAND)"
#endif
" (C) 2001-2003 Red Hat, Inc.\n");
jffs2_inode_cachep = kmem_cache_create("jffs2_i",
sizeof(struct jffs2_inode_info),
0, SLAB_RECLAIM_ACCOUNT,
jffs2_i_init_once, NULL);
if (!jffs2_inode_cachep) {
printk(KERN_ERR "JFFS2 error: Failed to initialise inode cache\n");
return -ENOMEM;
}
ret = jffs2_compressors_init();
if (ret) {
printk(KERN_ERR "JFFS2 error: Failed to initialise compressors\n");
goto out;
}
ret = jffs2_create_slab_caches();
if (ret) {
printk(KERN_ERR "JFFS2 error: Failed to initialise slab caches\n");
goto out_compressors;
}
ret = register_filesystem(&jffs2_fs_type);
if (ret) {
printk(KERN_ERR "JFFS2 error: Failed to register filesystem\n");
goto out_slab;
}
return 0;
out_slab:
jffs2_destroy_slab_caches();
out_compressors:
jffs2_compressors_exit();
out:
kmem_cache_destroy(jffs2_inode_cachep);
return ret;
}
static void __exit exit_jffs2_fs(void)
{
unregister_filesystem(&jffs2_fs_type);
jffs2_destroy_slab_caches();
jffs2_compressors_exit();
kmem_cache_destroy(jffs2_inode_cachep);
}
module_init(init_jffs2_fs);
module_exit(exit_jffs2_fs);
MODULE_DESCRIPTION("The Journalling Flash File System, v2");
MODULE_AUTHOR("Red Hat, Inc.");
MODULE_LICENSE("GPL"); // Actually dual-licensed, but it doesn't matter for
// the sake of this tag. It's Free Software.
