root/fs/jffs2/super.c

DEFINITIONS

1. jffs2_alloc_inode
2. jffs2_destroy_inode
3. jffs2_i_init_once
4. jffs2_sync_fs
5. jffs2_fill_super
6. jffs2_get_sb
7. jffs2_put_super
8. jffs2_kill_sb
9. init_jffs2_fs
10. exit_jffs2_fs

/*
 * JFFS2 -- Journalling Flash File System, Version 2.
 *
 * Copyright © 2001-2007 Red Hat, Inc.
 *
 * Created by David Woodhouse <dwmw2@infradead.org>
 *
 * For licensing information, see the file 'LICENCE' in this directory.
 *
 */

#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/err.h>
#include <linux/mount.h>
#include <linux/jffs2.h>
#include <linux/pagemap.h>
#include <linux/mtd/super.h>
#include <linux/ctype.h>
#include <linux/namei.h>
#include "compr.h"
#include "nodelist.h"

static void jffs2_put_super(struct super_block *);

static struct kmem_cache *jffs2_inode_cachep;

static struct inode *jffs2_alloc_inode(struct super_block *sb)
{
        struct jffs2_inode_info *f;

        f = kmem_cache_alloc(jffs2_inode_cachep, GFP_KERNEL);
        if (!f)
                return NULL;
        return &f->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)
{
        struct jffs2_inode_info *f = foo;

        mutex_init(&f->sem);
        inode_init_once(&f->vfs_inode);
}

static int jffs2_sync_fs(struct super_block *sb, int wait)
{
        struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);

        mutex_lock(&c->alloc_sem);
        jffs2_flush_wbuf_pad(c);
        mutex_unlock(&c->alloc_sem);
        return 0;
}

static const struct super_operations jffs2_super_operations =
{
        .alloc_inode =  jffs2_alloc_inode,
        .destroy_inode =jffs2_destroy_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,
};

/*
 * fill in the superblock
 */
static int jffs2_fill_super(struct super_block *sb, void *data, int silent)
{
        struct jffs2_sb_info *c;

        D1(printk(KERN_DEBUG "jffs2_get_sb_mtd():"
                  " New superblock for device %d (\"%s\")\n",
                  sb->s_mtd->index, sb->s_mtd->name));

        c = kzalloc(sizeof(*c), GFP_KERNEL);
        if (!c)
                return -ENOMEM;

        c->mtd = sb->s_mtd;
        c->os_priv = sb;
        sb->s_fs_info = c;

        /* Initialize JFFS2 superblock locks, the further initialization will
         * be done later */
        mutex_init(&c->alloc_sem);
        mutex_init(&c->erase_free_sem);
        init_waitqueue_head(&c->erase_wait);
        init_waitqueue_head(&c->inocache_wq);
        spin_lock_init(&c->erase_completion_lock);
        spin_lock_init(&c->inocache_lock);

        sb->s_op = &jffs2_super_operations;
        sb->s_flags = sb->s_flags | MS_NOATIME;
        sb->s_xattr = jffs2_xattr_handlers;
#ifdef CONFIG_JFFS2_FS_POSIX_ACL
        sb->s_flags |= MS_POSIXACL;
#endif
        return jffs2_do_fill_super(sb, data, silent);
}

static int jffs2_get_sb(struct file_system_type *fs_type,
                        int flags, const char *dev_name,
                        void *data, struct vfsmount *mnt)
{
        return get_sb_mtd(fs_type, flags, dev_name, data, jffs2_fill_super,
                          mnt);
}

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"));

        mutex_lock(&c->alloc_sem);
        jffs2_flush_wbuf_pad(c);
        mutex_unlock(&c->alloc_sem);

        jffs2_sum_exit(c);

        jffs2_free_ino_caches(c);
        jffs2_free_raw_node_refs(c);
        if (jffs2_blocks_use_vmalloc(c))
                vfree(c->blocks);
        else
                kfree(c->blocks);
        jffs2_flash_cleanup(c);
        kfree(c->inocache_list);
        jffs2_clear_xattr_subsystem(c);
        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);
        kill_mtd_super(sb);
        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;

        /* Paranoia checks for on-medium structures. If we ask GCC
           to pack them with __attribute__((packed)) then it _also_
           assumes that they're not aligned -- so it emits crappy
           code on some architectures. Ideally we want an attribute
           which means just 'no padding', without the alignment
           thing. But GCC doesn't have that -- we have to just
           hope the structs are the right sizes, instead. */
        BUILD_BUG_ON(sizeof(struct jffs2_unknown_node) != 12);
        BUILD_BUG_ON(sizeof(struct jffs2_raw_dirent) != 40);
        BUILD_BUG_ON(sizeof(struct jffs2_raw_inode) != 68);
        BUILD_BUG_ON(sizeof(struct jffs2_raw_summary) != 32);

        printk(KERN_INFO "JFFS2 version 2.2."
#ifdef CONFIG_JFFS2_FS_WRITEBUFFER
               " (NAND)"
#endif
#ifdef CONFIG_JFFS2_SUMMARY
               " (SUMMARY) "
#endif
               " © 2001-2006 Red Hat, Inc.\n");

        jffs2_inode_cachep = kmem_cache_create("jffs2_i",
                                             sizeof(struct jffs2_inode_info),
                                             0, (SLAB_RECLAIM_ACCOUNT|
                                                SLAB_MEM_SPREAD),
                                             jffs2_i_init_once);
        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.