/* * JFFS2 -- Journalling Flash File System, Version 2. * * Copyright (C) 2001-2003 Red Hat, Inc. * * Created by David Woodhouse <dwmw2@redhat.com> * * For licensing information, see the file 'LICENCE' in this directory. * * $Id: super.c,v 1.99 2004/08/24 07:59:57 dwmw2 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 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,};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"));	if (!(sb->s_flags & MS_RDONLY))		jffs2_stop_garbage_collect_thread(c);	down(&c->alloc_sem);	jffs2_flush_wbuf_pad(c);	up(&c->alloc_sem);	jffs2_free_ino_caches(c);	jffs2_free_raw_node_refs(c);	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);	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_NAND	       " (NAND)"#endif	       " (C) 2001-2003 Red Hat, Inc.\n");	jffs2_inode_cachep = kmem_cache_create("jffs2_i",					     sizeof(struct jffs2_inode_info),					     0, SLAB_HWCACHE_ALIGN|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.