aboutsummaryrefslogtreecommitdiffstats
path: root/fs/jffs2/super.c
diff options
context:
space:
mode:
Diffstat (limited to 'fs/jffs2/super.c')
-rw-r--r--fs/jffs2/super.c365
1 files changed, 365 insertions, 0 deletions
diff --git a/fs/jffs2/super.c b/fs/jffs2/super.c
new file mode 100644
index 000000000000..6b2a441d2766
--- /dev/null
+++ b/fs/jffs2/super.c
@@ -0,0 +1,365 @@
+/*
+ * 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 1.104 2004/11/23 15:37:31 gleixner 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"));
+
+ 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);
+ 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);
+ 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_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.