text: /*
   * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
   *
   * Copyright (C) 2002-2010 Aleph One Ltd.
   *   for Toby Churchill Ltd and Brightstar Engineering
   *
   * Created by Charles Manning <charles@aleph1.co.uk>
   * Acknowledgements:
   * Luc van OostenRyck for numerous patches.
   * Nick Bane for numerous patches.
   * Nick Bane for 2.5/2.6 integration.
   * Andras Toth for mknod rdev issue.
   * Michael Fischer for finding the problem with inode inconsistency.
   * Some code bodily lifted from JFFS
   *
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License version 2 as
   * published by the Free Software Foundation.
   */
  
  /*
   *
   * This is the file system front-end to YAFFS that hooks it up to
   * the VFS.
   *
   * Special notes:
   * >> 2.4: sb->u.generic_sbp points to the yaffs_dev_t associated with
   *         this superblock
   * >> 2.6: sb->s_fs_info  points to the yaffs_dev_t associated with this
   *         superblock
   * >> inode->u.generic_ip points to the associated yaffs_obj_t.
   */
  
  /*
   * There are two variants of the VFS glue code. This variant should compile
   * for any version of Linux.
   */
  #include <linux/version.h>
  
  #if (LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 10))
  #define YAFFS_COMPILE_BACKGROUND
  #if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,6, 23))
  #define YAFFS_COMPILE_FREEZER
  #endif
  #endif
  
  #if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,28))
  #define YAFFS_COMPILE_EXPORTFS
  #endif
  
  #if (LINUX_VERSION_CODE > KERNEL_VERSION(2,6,35))
  #define YAFFS_USE_SETATTR_COPY
  #define YAFFS_USE_TRUNCATE_SETSIZE
  #endif
  #if (LINUX_VERSION_CODE > KERNEL_VERSION(2,6,35))
  #define YAFFS_HAS_EVICT_INODE
  #endif
  
  #if (LINUX_VERSION_CODE > KERNEL_VERSION(2,6,13))
  #define YAFFS_NEW_FOLLOW_LINK 1
  #else
  #define YAFFS_NEW_FOLLOW_LINK 0
  #endif
  
  #if (LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 19))
  #include <linux/config.h>
  #endif
  
  #include <linux/kernel.h>
  #include <linux/module.h>
  #include <linux/slab.h>
  #include <linux/init.h>
  #include <linux/fs.h>
  #include <linux/proc_fs.h>
  #include <linux/smp_lock.h>
  #include <linux/pagemap.h>
  #include <linux/mtd/mtd.h>
  #include <linux/interrupt.h>
  #include <linux/string.h>
  #include <linux/ctype.h>
  
  #if (YAFFS_NEW_FOLLOW_LINK == 1)
  #include <linux/namei.h>
  #endif
  
  #ifdef YAFFS_COMPILE_EXPORTFS
  #include <linux/exportfs.h>
  #endif
  
  #ifdef YAFFS_COMPILE_BACKGROUND
  #include <linux/kthread.h>
  #include <linux/delay.h>
  #endif
  #ifdef YAFFS_COMPILE_FREEZER
  #include <linux/freezer.h>
  #endif
  
  #include <asm/div64.h>
  
  #if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 5, 0))
  
  #include <linux/statfs.h>
  
  #define UnlockPage(p) unlock_page(p)
  #define Page_Uptodate(page)	test_bit(PG_uptodate, &(page)->flags)
  
  /* FIXME: use sb->s_id instead ? */
  #define yaffs_devname(sb, buf)	bdevname(sb->s_bdev, buf)
  
  #else
  
  #include <linux/locks.h>
  #define	BDEVNAME_SIZE		0
  #define	yaffs_devname(sb, buf)	kdevname(sb->s_dev)
  
  #if (LINUX_VERSION_CODE < KERNEL_VERSION(2, 5, 0))
  /* added NCB 26/5/2006 for 2.4.25-vrs2-tcl1 kernel */
  #define __user
  #endif
  
  #endif
  
  #if (LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 26))
  #define YPROC_ROOT  (&proc_root)
  #else
  #define YPROC_ROOT  NULL
  #endif
  
  #if (LINUX_VERSION_CODE < KERNEL_VERSION(2,6,26))
  #define Y_INIT_TIMER(a)	init_timer(a)
  #else
  #define Y_INIT_TIMER(a)	init_timer_on_stack(a)
  #endif
  
  #if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 17))
  #define WRITE_SIZE_STR "writesize"
  #define WRITE_SIZE(mtd) ((mtd)->writesize)
  #else
  #define WRITE_SIZE_STR "oobblock"
  #define WRITE_SIZE(mtd) ((mtd)->oobblock)
  #endif
  
  #if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 27))
  #define YAFFS_USE_WRITE_BEGIN_END 1
  #else
  #define YAFFS_USE_WRITE_BEGIN_END 0
  #endif
  
  #if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 28))
  static uint32_t YCALCBLOCKS(uint64_t partition_size, uint32_t block_size)
  {
  	uint64_t result = partition_size;
  	do_div(result, block_size);
  	return (uint32_t)result;
  }
  #else
  #define YCALCBLOCKS(s, b) ((s)/(b))
  #endif
  
  #include <linux/uaccess.h>
  #include <linux/mtd/mtd.h>
  
  #include "yportenv.h"
  #include "yaffs_trace.h"
  #include "yaffs_guts.h"
  
  #include "yaffs_linux.h"
  
  #include "yaffs_mtdif.h"
  #include "yaffs_mtdif1.h"
  #include "yaffs_mtdif2.h"
  
  unsigned int yaffs_trace_mask = YAFFS_TRACE_BAD_BLOCKS | YAFFS_TRACE_ALWAYS;
  unsigned int yaffs_wr_attempts = YAFFS_WR_ATTEMPTS;
  unsigned int yaffs_auto_checkpoint = 1;
  unsigned int yaffs_gc_control = 1;
  unsigned int yaffs_bg_enable = 1;
  
  /* Module Parameters */
  #if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 5, 0))
  module_param(yaffs_trace_mask, uint, 0644);
  module_param(yaffs_wr_attempts, uint, 0644);
  module_param(yaffs_auto_checkpoint, uint, 0644);
  module_param(yaffs_gc_control, uint, 0644);
  module_param(yaffs_bg_enable, uint, 0644);
  #else
  MODULE_PARM(yaffs_trace_mask, "i");
  MODULE_PARM(yaffs_wr_attempts, "i");
  MODULE_PARM(yaffs_auto_checkpoint, "i");
  MODULE_PARM(yaffs_gc_control, "i");
  #endif
  
  #if (LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 25))
  /* use iget and read_inode */
  #define Y_IGET(sb, inum) iget((sb), (inum))
  static void yaffs_read_inode(struct inode *inode);
  
  #else
  /* Call local equivalent */
  #define YAFFS_USE_OWN_IGET
  #define Y_IGET(sb, inum) yaffs_iget((sb), (inum))
  
  static struct inode *yaffs_iget(struct super_block *sb, unsigned long ino);
  #endif
  
  #if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 18))
  #define yaffs_InodeToObjectLV(iptr) ((iptr)->i_private)
  #else
  #define yaffs_InodeToObjectLV(iptr) ((iptr)->u.generic_ip)
  #endif
  
  #define yaffs_InodeToObject(iptr) ((yaffs_obj_t *)(yaffs_InodeToObjectLV(iptr)))
  #define yaffs_dentry_to_obj(dptr) yaffs_InodeToObject((dptr)->d_inode)
  
  #if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 5, 0))
  #define yaffs_SuperToDevice(sb)	((yaffs_dev_t *)sb->s_fs_info)
  #else
  #define yaffs_SuperToDevice(sb)	((yaffs_dev_t *)sb->u.generic_sbp)
  #endif
  
  
  #define update_dir_time(dir) do {\
  			(dir)->i_ctime = (dir)->i_mtime = CURRENT_TIME; \
  		} while(0)
  		
  static void yaffs_put_super(struct super_block *sb);
  
  static ssize_t yaffs_file_write(struct file *f, const char *buf, size_t n,
  				loff_t *pos);
  static ssize_t yaffs_hold_space(struct file *f);
  static void yaffs_release_space(struct file *f);
  
  #if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 17))
  static int yaffs_file_flush(struct file *file, fl_owner_t id);
  #else
  static int yaffs_file_flush(struct file *file);
  #endif
  
  #if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 34))
  static int yaffs_sync_object(struct file *file, int datasync);
  #else
  static int yaffs_sync_object(struct file *file, struct dentry *dentry,
  				int datasync);
  #endif
  
  static int yaffs_readdir(struct file *f, void *dirent, filldir_t filldir);
  
  #if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 5, 0))
  static int yaffs_create(struct inode *dir, struct dentry *dentry, int mode,
  			struct nameidata *n);
  static struct dentry *yaffs_lookup(struct inode *dir, struct dentry *dentry,
  					struct nameidata *n);
  #else
  static int yaffs_create(struct inode *dir, struct dentry *dentry, int mode);
  static struct dentry *yaffs_lookup(struct inode *dir, struct dentry *dentry);
  #endif
  static int yaffs_link(struct dentry *old_dentry, struct inode *dir,
  			struct dentry *dentry);
  static int yaffs_unlink(struct inode *dir, struct dentry *dentry);
  static int yaffs_symlink(struct inode *dir, struct dentry *dentry,
  			const char *symname);
  static int yaffs_mkdir(struct inode *dir, struct dentry *dentry, int mode);
  
  #if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 5, 0))
  static int yaffs_mknod(struct inode *dir, struct dentry *dentry, int mode,
  			dev_t dev);
  #else
  static int yaffs_mknod(struct inode *dir, struct dentry *dentry, int mode,
  			int dev);
  #endif
  static int yaffs_rename(struct inode *old_dir, struct dentry *old_dentry,
  			struct inode *new_dir, struct dentry *new_dentry);
  static int yaffs_setattr(struct dentry *dentry, struct iattr *attr);
  
  #if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 17))
  static int yaffs_sync_fs(struct super_block *sb, int wait);
  static void yaffs_write_super(struct super_block *sb);
  #else
  static int yaffs_sync_fs(struct super_block *sb);
  static int yaffs_write_super(struct super_block *sb);
  #endif
  
  #if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 17))
  static int yaffs_statfs(struct dentry *dentry, struct kstatfs *buf);
  #elif (LINUX_VERSION_CODE > KERNEL_VERSION(2, 5, 0))
  static int yaffs_statfs(struct super_block *sb, struct kstatfs *buf);
  #else
  static int yaffs_statfs(struct super_block *sb, struct statfs *buf);
  #endif
  
  #ifdef YAFFS_HAS_PUT_INODE
  static void yaffs_put_inode(struct inode *inode);
  #endif
  
  #ifdef YAFFS_HAS_EVICT_INODE
  static void yaffs_evict_inode(struct inode *);
  #else
  static void yaffs_delete_inode(struct inode *);
  static void yaffs_clear_inode(struct inode *);
  #endif
  
  static int yaffs_readpage(struct file *file, struct page *page);
  #if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 5, 0))
  static int yaffs_writepage(struct page *page, struct writeback_control *wbc);
  #else
  static int yaffs_writepage(struct page *page);
  #endif
  
  #ifdef CONFIG_YAFFS_XATTR
  int yaffs_setxattr(struct dentry *dentry, const char *name,
  			const void *value, size_t size, int flags);
  ssize_t yaffs_getxattr(struct dentry *dentry, const char *name, void *buff,
  			size_t size);
  int yaffs_removexattr(struct dentry *dentry, const char *name);
  ssize_t yaffs_listxattr(struct dentry *dentry, char *buff, size_t size);
  #endif
  
  
  #if (YAFFS_USE_WRITE_BEGIN_END != 0)
  static int yaffs_write_begin(struct file *filp, struct address_space *mapping,
  				loff_t pos, unsigned len, unsigned flags,
  				struct page **pagep, void **fsdata);
  static int yaffs_write_end(struct file *filp, struct address_space *mapping,
  				loff_t pos, unsigned len, unsigned copied,
  				struct page *pg, void *fsdadata);
  #else
  static int yaffs_prepare_write(struct file *f, struct page *pg,
  				unsigned offset, unsigned to);
  static int yaffs_commit_write(struct file *f, struct page *pg, unsigned offset,
  				unsigned to);
  
  #endif
  
  static int yaffs_readlink(struct dentry *dentry, char __user *buffer,
  				int buflen);
  #if (YAFFS_NEW_FOLLOW_LINK == 1)
  void yaffs_put_link(struct dentry *dentry, struct nameidata *nd, void *alias);
  static void *yaffs_follow_link(struct dentry *dentry, struct nameidata *nd);
  #else
  static int yaffs_follow_link(struct dentry *dentry, struct nameidata *nd);
  #endif
  
  static void yaffs_touch_super(yaffs_dev_t *dev);
  
  static loff_t yaffs_dir_llseek(struct file *file, loff_t offset, int origin);
  
  static int yaffs_vfs_setattr(struct inode *, struct iattr *);
  
  
  static struct address_space_operations yaffs_file_address_operations = {
  	.readpage = yaffs_readpage,
  	.writepage = yaffs_writepage,
  #if (YAFFS_USE_WRITE_BEGIN_END > 0)
  	.write_begin = yaffs_write_begin,
  	.write_end = yaffs_write_end,
  #else
  	.prepare_write = yaffs_prepare_write,
  	.commit_write = yaffs_commit_write,
  #endif
  };
  
  
  #if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 22))
  static const struct file_operations yaffs_file_operations = {
  	.read = do_sync_read,
  	.write = do_sync_write,
  	.aio_read = generic_file_aio_read,
  	.aio_write = generic_file_aio_write,
  	.mmap = generic_file_mmap,
  	.flush = yaffs_file_flush,
  	.fsync = yaffs_sync_object,
  	.splice_read = generic_file_splice_read,
  	.splice_write = generic_file_splice_write,
  	.llseek = generic_file_llseek,
  };
  
  #elif (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 18))
  
  static const struct file_operations yaffs_file_operations = {
  	.read = do_sync_read,
  	.write = do_sync_write,
  	.aio_read = generic_file_aio_read,
  	.aio_write = generic_file_aio_write,
  	.mmap = generic_file_mmap,
  	.flush = yaffs_file_flush,
  	.fsync = yaffs_sync_object,
  	.sendfile = generic_file_sendfile,
  };
  
  #else
  
  static const struct file_operations yaffs_file_operations = {
  	.read = generic_file_read,
  	.write = generic_file_write,
  	.mmap = generic_file_mmap,
  	.flush = yaffs_file_flush,
  	.fsync = yaffs_sync_object,
  #if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 5, 0))
  	.sendfile = generic_file_sendfile,
  #endif
  };
  #endif
  
  #if (LINUX_VERSION_CODE < KERNEL_VERSION(2,6,25))
  static void zero_user_segment(struct page *page, unsigned start, unsigned end)
  {
  	void * kaddr = kmap_atomic(page, KM_USER0);
  	memset(kaddr + start, 0, end - start);
  	kunmap_atomic(kaddr, KM_USER0);
  	flush_dcache_page(page);
  }
  #endif
  
  
  static const struct inode_operations yaffs_file_inode_operations = {
  	.setattr = yaffs_setattr,
  #ifdef CONFIG_YAFFS_XATTR
  	.setxattr = yaffs_setxattr,
  	.getxattr = yaffs_getxattr,
  	.listxattr = yaffs_listxattr,
  	.removexattr = yaffs_removexattr,
  #endif
  };
  
  static const struct inode_operations yaffs_symlink_inode_operations = {
  	.readlink = yaffs_readlink,
  	.follow_link = yaffs_follow_link,
  #if (YAFFS_NEW_FOLLOW_LINK == 1)
  	.put_link = yaffs_put_link,
  #endif
  	.setattr = yaffs_setattr,
  #ifdef CONFIG_YAFFS_XATTR
  	.setxattr = yaffs_setxattr,
  	.getxattr = yaffs_getxattr,
  	.listxattr = yaffs_listxattr,
  	.removexattr = yaffs_removexattr,
  #endif
  };
  
  static const struct inode_operations yaffs_dir_inode_operations = {
  	.create = yaffs_create,
  	.lookup = yaffs_lookup,
  	.link = yaffs_link,
  	.unlink = yaffs_unlink,
  	.symlink = yaffs_symlink,
  	.mkdir = yaffs_mkdir,
  	.rmdir = yaffs_unlink,
  	.mknod = yaffs_mknod,
  	.rename = yaffs_rename,
  	.setattr = yaffs_setattr,
  #ifdef CONFIG_YAFFS_XATTR
  	.setxattr = yaffs_setxattr,
  	.getxattr = yaffs_getxattr,
  	.listxattr = yaffs_listxattr,
  	.removexattr = yaffs_removexattr,
  #endif
  };
  
  static const struct file_operations yaffs_dir_operations = {
  	.read = generic_read_dir,
  	.readdir = yaffs_readdir,
  	.fsync = yaffs_sync_object,
  	.llseek = yaffs_dir_llseek,
  };
  
  static const struct super_operations yaffs_super_ops = {
  	.statfs = yaffs_statfs,
  
  #ifndef YAFFS_USE_OWN_IGET
  	.read_inode = yaffs_read_inode,
  #endif
  #ifdef YAFFS_HAS_PUT_INODE
  	.put_inode = yaffs_put_inode,
  #endif
  	.put_super = yaffs_put_super,
  #ifdef YAFFS_HAS_EVICT_INODE
  	.evict_inode = yaffs_evict_inode,
  #else
  	.delete_inode = yaffs_delete_inode,
  	.clear_inode = yaffs_clear_inode,
  #endif
  	.sync_fs = yaffs_sync_fs,
  	.write_super = yaffs_write_super,
  };
  
  
  static  int yaffs_vfs_setattr(struct inode *inode, struct iattr *attr)
  {
  #ifdef  YAFFS_USE_SETATTR_COPY
  	setattr_copy(inode,attr);
  	return 0;
  #else
  	return inode_setattr(inode, attr);
  #endif
  
  }
  
  static  int yaffs_vfs_setsize(struct inode *inode, loff_t newsize)
  {
  #ifdef  YAFFS_USE_TRUNCATE_SETSIZE
  	truncate_setsize(inode,newsize);
  	return 0;
  #else
  	truncate_inode_pages(&inode->i_data,newsize);
  	return 0;
  #endif
  
  }
  
  static unsigned yaffs_gc_control_callback(yaffs_dev_t *dev)
  {
  	return yaffs_gc_control;
  }
                  	                                                                                          	
  static void yaffs_gross_lock(yaffs_dev_t *dev)
  {
  	T(YAFFS_TRACE_LOCK, (TSTR("yaffs locking %p\n"), current));
  	down(&(yaffs_dev_to_lc(dev)->grossLock));
  	T(YAFFS_TRACE_LOCK, (TSTR("yaffs locked %p\n"), current));
  }
  
  static void yaffs_gross_unlock(yaffs_dev_t *dev)
  {
  	T(YAFFS_TRACE_LOCK, (TSTR("yaffs unlocking %p\n"), current));
  	up(&(yaffs_dev_to_lc(dev)->grossLock));
  }
  
  #ifdef YAFFS_COMPILE_EXPORTFS
  
  static struct inode *
  yaffs2_nfs_get_inode(struct super_block *sb, uint64_t ino, uint32_t generation)
  {
  	return Y_IGET(sb, ino);
  }
  
  static struct dentry *
  yaffs2_fh_to_dentry(struct super_block *sb, struct fid *fid, int fh_len, int fh_type)
  {
  	return generic_fh_to_dentry(sb, fid, fh_len, fh_type, yaffs2_nfs_get_inode) ;
  }
  
  static struct dentry *
   yaffs2_fh_to_parent(struct super_block *sb, struct fid *fid, int fh_len, int fh_type)
  {
  	return generic_fh_to_parent(sb, fid, fh_len, fh_type, yaffs2_nfs_get_inode);
  }
  
  struct dentry *yaffs2_get_parent(struct dentry *dentry)
  {
  
  	struct super_block *sb = dentry->d_inode->i_sb;
  	struct dentry *parent = ERR_PTR(-ENOENT);
  	struct inode *inode;
  	unsigned long parent_ino;
  	yaffs_obj_t *d_obj;
  	yaffs_obj_t *parent_obj;
  
  	d_obj = yaffs_InodeToObject(dentry->d_inode);
  
  	if (d_obj) {
  		parent_obj = d_obj->parent;
  		if (parent_obj) {
  			parent_ino = yaffs_get_obj_inode(parent_obj);
  			inode = Y_IGET(sb, parent_ino);
  
  			if (IS_ERR(inode)) {
  				parent = ERR_CAST(inode);
  			} else {
  				parent = d_obtain_alias(inode);
  				if (!IS_ERR(parent)) {
  					parent = ERR_PTR(-ENOMEM);
  					iput(inode);
  				}
  			}
  		}
  	}
  
  	return parent;
  }
  
  /* Just declare a zero structure as a NULL value implies
   * using the default functions of exportfs.
   */
  
  static struct export_operations yaffs_export_ops =
  {
  	.fh_to_dentry = yaffs2_fh_to_dentry,
  	.fh_to_parent = yaffs2_fh_to_parent,
  	.get_parent = yaffs2_get_parent,
  } ;
  
  #endif
  
  /*-----------------------------------------------------------------*/
  /* Directory search context allows us to unlock access to yaffs during
   * filldir without causing problems with the directory being modified.
   * This is similar to the tried and tested mechanism used in yaffs direct.
   *
   * A search context iterates along a doubly linked list of siblings in the
   * directory. If the iterating object is deleted then this would corrupt
   * the list iteration, likely causing a crash. The search context avoids
   * this by using the remove_obj_fn to move the search context to the
   * next object before the object is deleted.
   *
   * Many readdirs (and thus seach conexts) may be alive simulateously so
   * each yaffs_dev_t has a list of these.
   *
   * A seach context lives for the duration of a readdir.
   *
   * All these functions must be called while yaffs is locked.
   */
  
  struct yaffs_SearchContext {
  	yaffs_dev_t *dev;
  	yaffs_obj_t *dirObj;
  	yaffs_obj_t *nextReturn;
  	struct ylist_head others;
  };
  
  /*
   * yaffs_NewSearch() creates a new search context, initialises it and
   * adds it to the device's search context list.
   *
   * Called at start of readdir.
   */
  static struct yaffs_SearchContext * yaffs_NewSearch(yaffs_obj_t *dir)
  {
  	yaffs_dev_t *dev = dir->my_dev;
  	struct yaffs_SearchContext *sc = YMALLOC(sizeof(struct yaffs_SearchContext));
  	if(sc){
  		sc->dirObj = dir;
  		sc->dev = dev;
  		if( ylist_empty(&sc->dirObj->variant.dir_variant.children))
  			sc->nextReturn = NULL;
  		else
  			sc->nextReturn = ylist_entry(
                                  dir->variant.dir_variant.children.next,
  				yaffs_obj_t,siblings);
  		YINIT_LIST_HEAD(&sc->others);
  		ylist_add(&sc->others,&(yaffs_dev_to_lc(dev)->searchContexts));
  	}
  	return sc;
  }
  
  /*
   * yaffs_search_end() disposes of a search context and cleans up.
   */
  static void yaffs_search_end(struct yaffs_SearchContext * sc)
  {
  	if(sc){
  		ylist_del(&sc->others);
  		YFREE(sc);
  	}
  }
  
  /*
   * yaffs_search_advance() moves a search context to the next object.
   * Called when the search iterates or when an object removal causes
   * the search context to be moved to the next object.
   */
  static void yaffs_search_advance(struct yaffs_SearchContext *sc)
  {
          if(!sc)
                  return;
  
          if( sc->nextReturn == NULL ||
                  ylist_empty(&sc->dirObj->variant.dir_variant.children))
                  sc->nextReturn = NULL;
          else {
                  struct ylist_head *next = sc->nextReturn->siblings.next;
  
                  if( next == &sc->dirObj->variant.dir_variant.children)
                          sc->nextReturn = NULL; /* end of list */
                  else
                          sc->nextReturn = ylist_entry(next,yaffs_obj_t,siblings);
          }
  }
  
  /*
   * yaffs_remove_obj_callback() is called when an object is unlinked.
   * We check open search contexts and advance any which are currently
   * on the object being iterated.
   */
  static void yaffs_remove_obj_callback(yaffs_obj_t *obj)
  {
  
          struct ylist_head *i;
          struct yaffs_SearchContext *sc;
          struct ylist_head *search_contexts = &(yaffs_dev_to_lc(obj->my_dev)->searchContexts);
  
  
          /* Iterate through the directory search contexts.
           * If any are currently on the object being removed, then advance
           * the search context to the next object to prevent a hanging pointer.
           */
           ylist_for_each(i, search_contexts) {
                  if (i) {
                          sc = ylist_entry(i, struct yaffs_SearchContext,others);
                          if(sc->nextReturn == obj)
                                  yaffs_search_advance(sc);
                  }
  	}
  
  }
  
  
  /*-----------------------------------------------------------------*/
  
  static int yaffs_readlink(struct dentry *dentry, char __user *buffer,
  			int buflen)
  {
  	unsigned char *alias;
  	int ret;
  
  	yaffs_dev_t *dev = yaffs_dentry_to_obj(dentry)->my_dev;
  
  	yaffs_gross_lock(dev);
  
  	alias = yaffs_get_symlink_alias(yaffs_dentry_to_obj(dentry));
  
  	yaffs_gross_unlock(dev);
  
  	if (!alias)
  		return -ENOMEM;
  
  	ret = vfs_readlink(dentry, buffer, buflen, alias);
  	kfree(alias);
  	return ret;
  }
  
  #if (YAFFS_NEW_FOLLOW_LINK == 1)
  static void *yaffs_follow_link(struct dentry *dentry, struct nameidata *nd)
  #else
  static int yaffs_follow_link(struct dentry *dentry, struct nameidata *nd)
  #endif
  {
  	unsigned char *alias;
  	int ret;
  	yaffs_dev_t *dev = yaffs_dentry_to_obj(dentry)->my_dev;
  
  	yaffs_gross_lock(dev);
  
  	alias = yaffs_get_symlink_alias(yaffs_dentry_to_obj(dentry));
  	yaffs_gross_unlock(dev);
  
  	if (!alias) {
  		ret = -ENOMEM;
  		goto out;
  	}
  
  #if (YAFFS_NEW_FOLLOW_LINK == 1)
  	nd_set_link(nd, alias);
  	ret = (int)alias;
  out:
  	return ERR_PTR(ret);
  #else
  	ret = vfs_follow_link(nd, alias);
  	kfree(alias);
  out:
  	return ret;
  #endif
  }
  
  #if (YAFFS_NEW_FOLLOW_LINK == 1)
  void yaffs_put_link(struct dentry *dentry, struct nameidata *nd, void *alias) {
  	kfree(alias);
  }
  #endif
  
  struct inode *yaffs_get_inode(struct super_block *sb, int mode, int dev,
  				yaffs_obj_t *obj);
  
  /*
   * Lookup is used to find objects in the fs
   */
  #if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 5, 0))
  
  static struct dentry *yaffs_lookup(struct inode *dir, struct dentry *dentry,
  				struct nameidata *n)
  #else
  static struct dentry *yaffs_lookup(struct inode *dir, struct dentry *dentry)
  #endif
  {
  	yaffs_obj_t *obj;
  	struct inode *inode = NULL;	/* NCB 2.5/2.6 needs NULL here */
  
  	yaffs_dev_t *dev = yaffs_InodeToObject(dir)->my_dev;
  
  	if(current != yaffs_dev_to_lc(dev)->readdirProcess)
  		yaffs_gross_lock(dev);
  
  	T(YAFFS_TRACE_OS,
  		(TSTR("yaffs_lookup for %d:%s\n"),
  		yaffs_InodeToObject(dir)->obj_id, dentry->d_name.name));
  
  	obj = yaffs_find_by_name(yaffs_InodeToObject(dir),
  					dentry->d_name.name);
  
  	obj = yaffs_get_equivalent_obj(obj);	/* in case it was a hardlink */
  
  	/* Can't hold gross lock when calling yaffs_get_inode() */
  	if(current != yaffs_dev_to_lc(dev)->readdirProcess)
  		yaffs_gross_unlock(dev);
  
  	if (obj) {
  		T(YAFFS_TRACE_OS,
  			(TSTR("yaffs_lookup found %d\n"), obj->obj_id));
  
  		inode = yaffs_get_inode(dir->i_sb, obj->yst_mode, 0, obj);
  
  		if (inode) {
  			T(YAFFS_TRACE_OS,
  				(TSTR("yaffs_loookup dentry \n")));
  /* #if 0 asserted by NCB for 2.5/6 compatability - falls through to
   * d_add even if NULL inode */
  #if 0
  			/*dget(dentry); // try to solve directory bug */
  			d_add(dentry, inode);
  
  			/* return dentry; */
  			return NULL;
  #endif
  		}
  
  	} else {
  		T(YAFFS_TRACE_OS,(TSTR("yaffs_lookup not found\n")));
  
  	}
  
  /* added NCB for 2.5/6 compatability - forces add even if inode is
   * NULL which creates dentry hash */
  	d_add(dentry, inode);
  
  	return NULL;
  }
  
  
  #ifdef YAFFS_HAS_PUT_INODE
  
  /* For now put inode is just for debugging
   * Put inode is called when the inode **structure** is put.
   */
  static void yaffs_put_inode(struct inode *inode)
  {
  	T(YAFFS_TRACE_OS,
  		(TSTR("yaffs_put_inode: ino %d, count %d\n"), (int)inode->i_ino,
  		atomic_read(&inode->i_count)));
  
  }
  #endif
  
  
  static void yaffs_unstitch_obj(struct inode *inode, yaffs_obj_t *obj)
  {
  	/* Clear the association between the inode and
  	 * the yaffs_obj_t.
  	 */
  	obj->my_inode = NULL;
  	yaffs_InodeToObjectLV(inode) = NULL;
  
  	/* If the object freeing was deferred, then the real
  	 * free happens now.
  	 * This should fix the inode inconsistency problem.
  	 */
  	yaffs_handle_defered_free(obj);
  }
  
  #ifdef YAFFS_HAS_EVICT_INODE
  /* yaffs_evict_inode combines into one operation what was previously done in
   * yaffs_clear_inode() and yaffs_delete_inode()
   *
   */
  static void yaffs_evict_inode( struct inode *inode)
  {
  	yaffs_obj_t *obj;
  	yaffs_dev_t *dev;
  	int deleteme = 0;
  
  	obj = yaffs_InodeToObject(inode);
  
  	T(YAFFS_TRACE_OS,
  		(TSTR("yaffs_evict_inode: ino %d, count %d %s\n"), (int)inode->i_ino,
  		atomic_read(&inode->i_count),
  		obj ? "object exists" : "null object"));
  
  	if (!inode->i_nlink && !is_bad_inode(inode))
  		deleteme = 1;
  	truncate_inode_pages(&inode->i_data,0);
  	end_writeback(inode);
  
  	if(deleteme && obj){
  		dev = obj->my_dev;
  		yaffs_gross_lock(dev);
  		yaffs_del_obj(obj);
  		yaffs_gross_unlock(dev);
  	}
  	if (obj) {
  		dev = obj->my_dev;
  		yaffs_gross_lock(dev);
  		yaffs_unstitch_obj(inode,obj);
  		yaffs_gross_unlock(dev);
  	}
  
  
  }
  #else
  
  /* clear is called to tell the fs to release any per-inode data it holds.
   * The object might still exist on disk and is just being thrown out of the cache
   * or else the object has actually been deleted and we're being called via
   * the chain
   *   yaffs_delete_inode() -> clear_inode()->yaffs_clear_inode()
   */
  
  static void yaffs_clear_inode(struct inode *inode)
  {
  	yaffs_obj_t *obj;
  	yaffs_dev_t *dev;
  
  	obj = yaffs_InodeToObject(inode);
  
  	T(YAFFS_TRACE_OS,
  		(TSTR("yaffs_clear_inode: ino %d, count %d %s\n"), (int)inode->i_ino,
  		atomic_read(&inode->i_count),
  		obj ? "object exists" : "null object"));
  
  	if (obj) {
  		dev = obj->my_dev;
  		yaffs_gross_lock(dev);
  		yaffs_unstitch_obj(inode,obj);
  		yaffs_gross_unlock(dev);
  	}
  
  }
  
  /* delete is called when the link count is zero and the inode
   * is put (ie. nobody wants to know about it anymore, time to
   * delete the file).
   * NB Must call clear_inode()
   */
  static void yaffs_delete_inode(struct inode *inode)
  {
  	yaffs_obj_t *obj = yaffs_InodeToObject(inode);
  	yaffs_dev_t *dev;
  
  	T(YAFFS_TRACE_OS,
  		(TSTR("yaffs_delete_inode: ino %d, count %d %s\n"), (int)inode->i_ino,
  		atomic_read(&inode->i_count),
  		obj ? "object exists" : "null object"));
  
  	if (obj) {
  		dev = obj->my_dev;
  		yaffs_gross_lock(dev);
  		yaffs_del_obj(obj);
  		yaffs_gross_unlock(dev);
  	}
  #if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 13))
  	truncate_inode_pages(&inode->i_data, 0);
  #endif
  	clear_inode(inode);
  }
  #endif
  
  
  #if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 17))
  static int yaffs_file_flush(struct file *file, fl_owner_t id)
  #else
  static int yaffs_file_flush(struct file *file)
  #endif
  {
  	yaffs_obj_t *obj = yaffs_dentry_to_obj(file->f_dentry);
  
  	yaffs_dev_t *dev = obj->my_dev;
  
  	T(YAFFS_TRACE_OS,
  		(TSTR("yaffs_file_flush object %d (%s)\n"), obj->obj_id,
  		obj->dirty ? "dirty" : "clean"));
  
  	yaffs_gross_lock(dev);
  
  	yaffs_flush_file(obj, 1, 0);
  
  	yaffs_gross_unlock(dev);
  
  	return 0;
  }
  
  static int yaffs_readpage_nolock(struct file *f, struct page *pg)
  {
  	/* Lifted from jffs2 */
  
  	yaffs_obj_t *obj;
  	unsigned char *pg_buf;
  	int ret;
  
  	yaffs_dev_t *dev;
  
  	T(YAFFS_TRACE_OS,
  		(TSTR("yaffs_readpage_nolock at %08x, size %08x\n"),
  		(unsigned)(pg->index << PAGE_CACHE_SHIFT),
  		(unsigned)PAGE_CACHE_SIZE));
  
  	obj = yaffs_dentry_to_obj(f->f_dentry);
  
  	dev = obj->my_dev;
  
  #if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 5, 0))
  	BUG_ON(!PageLocked(pg));
  #else
  	if (!PageLocked(pg))
  		PAGE_BUG(pg);
  #endif
  
  	pg_buf = kmap(pg);
  	/* FIXME: Can kmap fail? */
  
  	yaffs_gross_lock(dev);
  
  	ret = yaffs_file_rd(obj, pg_buf,
  				pg->index << PAGE_CACHE_SHIFT,
  				PAGE_CACHE_SIZE);
  
  	yaffs_gross_unlock(dev);
  
  	if (ret >= 0)
  		ret = 0;
  
  	if (ret) {
  		ClearPageUptodate(pg);
  		SetPageError(pg);
  	} else {
  		SetPageUptodate(pg);
  		ClearPageError(pg);
  	}
  
  	flush_dcache_page(pg);
  	kunmap(pg);
  
  	T(YAFFS_TRACE_OS, (TSTR("yaffs_readpage_nolock done\n")));
  	return ret;
  }
  
  static int yaffs_readpage_unlock(struct file *f, struct page *pg)
  {
  	int ret = yaffs_readpage_nolock(f, pg);
  	UnlockPage(pg);
  	return ret;
  }
  
  static int yaffs_readpage(struct file *f, struct page *pg)
  {
  	int ret;
  
  	T(YAFFS_TRACE_OS, (TSTR("yaffs_readpage\n")));
  	ret=yaffs_readpage_unlock(f, pg);
  	T(YAFFS_TRACE_OS, (TSTR("yaffs_readpage done\n")));
  	return ret;
  }
  
  /* writepage inspired by/stolen from smbfs */
  
  #if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 5, 0))
  static int yaffs_writepage(struct page *page, struct writeback_control *wbc)
  #else
  static int yaffs_writepage(struct page *page)
  #endif
  {
  	yaffs_dev_t *dev;
  	struct address_space *mapping = page->mapping;
  	struct inode *inode;
  	unsigned long end_index;
  	char *buffer;
  	yaffs_obj_t *obj;
  	int nWritten = 0;
  	unsigned n_bytes;
  	loff_t i_size;
  
  	if (!mapping)
  		BUG();
  	inode = mapping->host;
  	if (!inode)
  		BUG();
  	i_size = i_size_read(inode);
  
  	end_index = i_size >> PAGE_CACHE_SHIFT;
  
  	if(page->index < end_index)
  		n_bytes = PAGE_CACHE_SIZE;
  	else {
  		n_bytes = i_size & (PAGE_CACHE_SIZE -1);
  
  		if (page->index > end_index || !n_bytes) {
  			T(YAFFS_TRACE_OS,
  				(TSTR("yaffs_writepage at %08x, inode size = %08x!!!\n"),
  				(unsigned)(page->index << PAGE_CACHE_SHIFT),
  				(unsigned)inode->i_size));
  			T(YAFFS_TRACE_OS,
  				(TSTR("                -> don't care!!\n")));
  
  			zero_user_segment(page,0,PAGE_CACHE_SIZE);
  			set_page_writeback(page);
  			unlock_page(page);
  			end_page_writeback(page);
  			return 0;
  		}
  	}
  
  	if(n_bytes != PAGE_CACHE_SIZE)
  		zero_user_segment(page,n_bytes,PAGE_CACHE_SIZE);
  
  	get_page(page);
  
  	buffer = kmap(page);
  
  	obj = yaffs_InodeToObject(inode);
  	dev = obj->my_dev;
  	yaffs_gross_lock(dev);
  
  	T(YAFFS_TRACE_OS,
  		(TSTR("yaffs_writepage at %08x, size %08x\n"),
  		(unsigned)(page->index << PAGE_CACHE_SHIFT), n_bytes));
  	T(YAFFS_TRACE_OS,
  		(TSTR("writepag0: obj = %05x, ino = %05x\n"),
  		(int)obj->variant.file_variant.file_size, (int)inode->i_size));
  
  	nWritten = yaffs_wr_file(obj, buffer,
  			page->index << PAGE_CACHE_SHIFT, n_bytes, 0);
  
  	yaffs_touch_super(dev);
  
  	T(YAFFS_TRACE_OS,
  		(TSTR("writepag1: obj = %05x, ino = %05x\n"),
  		(int)obj->variant.file_variant.file_size, (int)inode->i_size));
  
  	yaffs_gross_unlock(dev);
  
  	kunmap(page);
  	set_page_writeback(page);
  	unlock_page(page);
  	end_page_writeback(page);
  	put_page(page);
  
  	return (nWritten == n_bytes) ? 0 : -ENOSPC;
  }
  
  
  #if (YAFFS_USE_WRITE_BEGIN_END > 0)
  static int yaffs_write_begin(struct file *filp, struct address_space *mapping,
  				loff_t pos, unsigned len, unsigned flags,
  				struct page **pagep, void **fsdata)
  {
  	struct page *pg = NULL;
  	pgoff_t index = pos >> PAGE_CACHE_SHIFT;
  
  	int ret = 0;
  	int space_held = 0;
  
  	/* Get a page */
  #if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 28)
  	pg = grab_cache_page_write_begin(mapping, index, flags);
  #else
  	pg = __grab_cache_page(mapping, index);
  #endif
  
  	*pagep = pg;
  	if (!pg) {
  		ret =  -ENOMEM;
  		goto out;
  	}
  	T(YAFFS_TRACE_OS,
  		(TSTR("start yaffs_write_begin index %d(%x) uptodate %d\n"),
  		(int)index,(int)index,Page_Uptodate(pg) ? 1 : 0));
  
  	/* Get fs space */
  	space_held = yaffs_hold_space(filp);
  
  	if (!space_held) {
  		ret = -ENOSPC;
  		goto out;
  	}
  
  	/* Update page if required */
  
  	if (!Page_Uptodate(pg))
  		ret = yaffs_readpage_nolock(filp, pg);
  
  	if (ret)
  		goto out;
  
  	/* Happy path return */
  	T(YAFFS_TRACE_OS, (TSTR("end yaffs_write_begin - ok\n")));
  
  	return 0;
  
  out:
  	T(YAFFS_TRACE_OS,
  		(TSTR("end yaffs_write_begin fail returning %d\n"), ret));
  	if (space_held)
  		yaffs_release_space(filp);
  	if (pg) {
  		unlock_page(pg);
  		page_cache_release(pg);
  	}
  	return ret;
  }
  
  #else
  
  static int yaffs_prepare_write(struct file *f, struct page *pg,
  				unsigned offset, unsigned to)
  {
  	T(YAFFS_TRACE_OS, (TSTR("yaffs_prepair_write\n")));
  
  	if (!Page_Uptodate(pg))
  		return yaffs_readpage_nolock(f, pg);
  	return 0;
  }
  #endif
  
  #if (YAFFS_USE_WRITE_BEGIN_END > 0)
  static int yaffs_write_end(struct file *filp, struct address_space *mapping,
  				loff_t pos, unsigned len, unsigned copied,
  				struct page *pg, void *fsdadata)
  {
  	int ret = 0;
  	void *addr, *kva;
  	uint32_t offset_into_page = pos & (PAGE_CACHE_SIZE - 1);
  
  	kva = kmap(pg);
  	addr = kva + offset_into_page;
  
  	T(YAFFS_TRACE_OS,
  		("yaffs_write_end addr %p pos %x n_bytes %d\n",
  		addr,(unsigned)pos, copied));
  
  	ret = yaffs_file_write(filp, addr, copied, &pos);
  
  	if (ret != copied) {
  		T(YAFFS_TRACE_OS,
  			(TSTR("yaffs_write_end not same size ret %d  copied %d\n"),
  			ret, copied));
  		SetPageError(pg);
  	} else {
  		/* Nothing */
  	}
  
  	kunmap(pg);
  
  	yaffs_release_space(filp);
  	unlock_page(pg);
  	page_cache_release(pg);
  	return ret;
  }
  #else
  
  static int yaffs_commit_write(struct file *f, struct page *pg, unsigned offset,
  				unsigned to)
  {
  	void *addr, *kva;
  
  	loff_t pos = (((loff_t) pg->index) << PAGE_CACHE_SHIFT) + offset;
  	int n_bytes = to - offset;
  	int nWritten;
  
  	unsigned spos = pos;
  	unsigned saddr;
  
  	kva = kmap(pg);
  	addr = kva + offset;
  
  	saddr = (unsigned) addr;
  
  	T(YAFFS_TRACE_OS,
  		(TSTR("yaffs_commit_write addr %x pos %x n_bytes %d\n"),
  		saddr, spos, n_bytes));
  
  	nWritten = yaffs_file_write(f, addr, n_bytes, &pos);
  
  	if (nWritten != n_bytes) {
  		T(YAFFS_TRACE_OS,
  			(TSTR("yaffs_commit_write not same size nWritten %d  n_bytes %d\n"),
  			nWritten, n_bytes));
  		SetPageError(pg);
  	} else {
  		/* Nothing */
  	}
  
  	kunmap(pg);
  
  	T(YAFFS_TRACE_OS,
  		(TSTR("yaffs_commit_write returning %d\n"),
  		nWritten == n_bytes ? 0 : nWritten));
  
  	return nWritten == n_bytes ? 0 : nWritten;
  }
  #endif
  
  
  static void yaffs_fill_inode_from_obj(struct inode *inode, yaffs_obj_t *obj)
  {
  	if (inode && obj) {
  
  
  		/* Check mode against the variant type and attempt to repair if broken. */
  		__u32 mode = obj->yst_mode;
  		switch (obj->variant_type) {
  		case YAFFS_OBJECT_TYPE_FILE:
  			if (!S_ISREG(mode)) {
  				obj->yst_mode &= ~S_IFMT;
  				obj->yst_mode |= S_IFREG;
  			}
  
  			break;
  		case YAFFS_OBJECT_TYPE_SYMLINK:
  			if (!S_ISLNK(mode)) {
  				obj->yst_mode &= ~S_IFMT;
  				obj->yst_mode |= S_IFLNK;
  			}
  
  			break;
  		case YAFFS_OBJECT_TYPE_DIRECTORY:
  			if (!S_ISDIR(mode)) {
  				obj->yst_mode &= ~S_IFMT;
  				obj->yst_mode |= S_IFDIR;
  			}
  
  			break;
  		case YAFFS_OBJECT_TYPE_UNKNOWN:
  		case YAFFS_OBJECT_TYPE_HARDLINK:
  		case YAFFS_OBJECT_TYPE_SPECIAL:
  		default:
  			/* TODO? */
  			break;
  		}
  
  		inode->i_flags |= S_NOATIME;
  
  		inode->i_ino = obj->obj_id;
  		inode->i_mode = obj->yst_mode;
  		inode->i_uid = obj->yst_uid;
  		inode->i_gid = obj->yst_gid;
  #if (LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 19))
  		inode->i_blksize = inode->i_sb->s_blocksize;
  #endif
  #if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 5, 0))
  
  		inode->i_rdev = old_decode_dev(obj->yst_rdev);
  		inode->i_atime.tv_sec = (time_t) (obj->yst_atime);
  		inode->i_atime.tv_nsec = 0;
  		inode->i_mtime.tv_sec = (time_t) obj->yst_mtime;
  		inode->i_mtime.tv_nsec = 0;
  		inode->i_ctime.tv_sec = (time_t) obj->yst_ctime;
  		inode->i_ctime.tv_nsec = 0;
  #else
  		inode->i_rdev = obj->yst_rdev;
  		inode->i_atime = obj->yst_atime;
  		inode->i_mtime = obj->yst_mtime;
  		inode->i_ctime = obj->yst_ctime;
  #endif
  		inode->i_size = yaffs_get_obj_length(obj);
  		inode->i_blocks = (inode->i_size + 511) >> 9;
  
  		inode->i_nlink = yaffs_get_obj_link_count(obj);
  
  		T(YAFFS_TRACE_OS,
  			(TSTR("yaffs_fill_inode mode %x uid %d gid %d size %d count %d\n"),
  			inode->i_mode, inode->i_uid, inode->i_gid,
  			(int)inode->i_size, atomic_read(&inode->i_count)));
  
  		switch (obj->yst_mode & S_IFMT) {
  		default:	/* fifo, device or socket */
  #if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 5, 0))
  			init_special_inode(inode, obj->yst_mode,
  					old_decode_dev(obj->yst_rdev));
  #else
  			init_special_inode(inode, obj->yst_mode,
  					(dev_t) (obj->yst_rdev));
  #endif
  			break;
  		case S_IFREG:	/* file */
  			inode->i_op = &yaffs_file_inode_operations;
  			inode->i_fop = &yaffs_file_operations;
  			inode->i_mapping->a_ops =
  				&yaffs_file_address_operations;
  			break;
  		case S_IFDIR:	/* directory */
  			inode->i_op = &yaffs_dir_inode_operations;
  			inode->i_fop = &yaffs_dir_operations;
  			break;
  		case S_IFLNK:	/* symlink */
  			inode->i_op = &yaffs_symlink_inode_operations;
  			break;
  		}
  
  		yaffs_InodeToObjectLV(inode) = obj;
  
  		obj->my_inode = inode;
  
  	} else {
  		T(YAFFS_TRACE_OS,
  			(TSTR("yaffs_FileInode invalid parameters\n")));
  	}
  
  }
  
  struct inode *yaffs_get_inode(struct super_block *sb, int mode, int dev,
  				yaffs_obj_t *obj)
  {
  	struct inode *inode;
  
  	if (!sb) {
  		T(YAFFS_TRACE_OS,
  			(TSTR("yaffs_get_inode for NULL super_block!!\n")));
  		return NULL;
  
  	}
  
  	if (!obj) {
  		T(YAFFS_TRACE_OS,
  			(TSTR("yaffs_get_inode for NULL object!!\n")));
  		return NULL;
  
  	}
  
  	T(YAFFS_TRACE_OS,
  		(TSTR("yaffs_get_inode for object %d\n"), obj->obj_id));
  
  	inode = Y_IGET(sb, obj->obj_id);
  	if (IS_ERR(inode))
  		return NULL;
  
  	/* NB Side effect: iget calls back to yaffs_read_inode(). */
  	/* iget also increments the inode's i_count */
  	/* NB You can't be holding grossLock or deadlock will happen! */
  
  	return inode;
  }
  
  static ssize_t yaffs_file_write(struct file *f, const char *buf, size_t n,
  				loff_t *pos)
  {
  	yaffs_obj_t *obj;
  	int nWritten, ipos;
  	struct inode *inode;
  	yaffs_dev_t *dev;
  
  	obj = yaffs_dentry_to_obj(f->f_dentry);
  
  	dev = obj->my_dev;
  
  	yaffs_gross_lock(dev);
  
  	inode = f->f_dentry->d_inode;
  
  	if (!S_ISBLK(inode->i_mode) && f->f_flags & O_APPEND)
  		ipos = inode->i_size;
  	else
  		ipos = *pos;
  
  	if (!obj)
  		T(YAFFS_TRACE_OS,
  			(TSTR("yaffs_file_write: hey obj is null!\n")));
  	else
  		T(YAFFS_TRACE_OS,
  			(TSTR("yaffs_file_write about to write writing %u(%x) bytes"
  			"to object %d at %d(%x)\n"),
  			(unsigned) n, (unsigned) n, obj->obj_id, ipos,ipos));
  
  	nWritten = yaffs_wr_file(obj, buf, ipos, n, 0);
  
  	yaffs_touch_super(dev);
  
  	T(YAFFS_TRACE_OS,
  		(TSTR("yaffs_file_write: %d(%x) bytes written\n"),
  		(unsigned )n,(unsigned)n));
  
  	if (nWritten > 0) {
  		ipos += nWritten;
  		*pos = ipos;
  		if (ipos > inode->i_size) {
  			inode->i_size = ipos;
  			inode->i_blocks = (ipos + 511) >> 9;
  
  			T(YAFFS_TRACE_OS,
  				(TSTR("yaffs_file_write size updated to %d bytes, "
  				"%d blocks\n"),
  				ipos, (int)(inode->i_blocks)));
  		}
  
  	}
  	yaffs_gross_unlock(dev);
  	return (nWritten == 0) && (n > 0) ? -ENOSPC : nWritten;
  }
  
  /* Space holding and freeing is done to ensure we have space available for write_begin/end */
  /* For now we just assume few parallel writes and check against a small number. */
  /* Todo: need to do this with a counter to handle parallel reads better */
  
  static ssize_t yaffs_hold_space(struct file *f)
  {
  	yaffs_obj_t *obj;
  	yaffs_dev_t *dev;
  
  	int n_free_chunks;
  
  
  	obj = yaffs_dentry_to_obj(f->f_dentry);
  
  	dev = obj->my_dev;
  
  	yaffs_gross_lock(dev);
  
  	n_free_chunks = yaffs_get_n_free_chunks(dev);
  
  	yaffs_gross_unlock(dev);
  
  	return (n_free_chunks > 20) ? 1 : 0;
  }
  
  static void yaffs_release_space(struct file *f)
  {
  	yaffs_obj_t *obj;
  	yaffs_dev_t *dev;
  
  
  	obj = yaffs_dentry_to_obj(f->f_dentry);
  
  	dev = obj->my_dev;
  
  	yaffs_gross_lock(dev);
  
  
  	yaffs_gross_unlock(dev);
  }
  
  
  static loff_t yaffs_dir_llseek(struct file *file, loff_t offset, int origin)
  {
  	long long retval;
  
  	lock_kernel();
  
  	switch (origin){
  	case 2:
  		offset += i_size_read(file->f_path.dentry->d_inode);
  		break;
  	case 1:
  		offset += file->f_pos;
  	}
  	retval = -EINVAL;
  
  	if (offset >= 0){
  		if (offset != file->f_pos)
  			file->f_pos = offset;
  
  		retval = offset;
  	}
  	unlock_kernel();
  	return retval;
  }
  
  
  static int yaffs_readdir(struct file *f, void *dirent, filldir_t filldir)
  {
  	yaffs_obj_t *obj;
  	yaffs_dev_t *dev;
          struct yaffs_SearchContext *sc;
  	struct inode *inode = f->f_dentry->d_inode;
  	unsigned long offset, curoffs;
  	yaffs_obj_t *l;
          int retVal = 0;
  
  	char name[YAFFS_MAX_NAME_LENGTH + 1];
  
  	obj = yaffs_dentry_to_obj(f->f_dentry);
  	dev = obj->my_dev;
  
  	yaffs_gross_lock(dev);
  
  	yaffs_dev_to_lc(dev)->readdirProcess = current;
  
  	offset = f->f_pos;
  
          sc = yaffs_NewSearch(obj);
          if(!sc){
                  retVal = -ENOMEM;
                  goto out;
          }
  
  	T(YAFFS_TRACE_OS, (TSTR("yaffs_readdir: starting at %d\n"), (int)offset));
  
  	if (offset == 0) {
  		T(YAFFS_TRACE_OS,
  			(TSTR("yaffs_readdir: entry . ino %d \n"),
  			(int)inode->i_ino));
  		yaffs_gross_unlock(dev);
  		if (filldir(dirent, ".", 1, offset, inode->i_ino, DT_DIR) < 0){
  			yaffs_gross_lock(dev);
  			goto out;
  		}
  		yaffs_gross_lock(dev);
  		offset++;
  		f->f_pos++;
  	}
  	if (offset == 1) {
  		T(YAFFS_TRACE_OS,
  			(TSTR("yaffs_readdir: entry .. ino %d \n"),
  			(int)f->f_dentry->d_parent->d_inode->i_ino));
  		yaffs_gross_unlock(dev);
  		if (filldir(dirent, "..", 2, offset,
  			f->f_dentry->d_parent->d_inode->i_ino, DT_DIR) < 0){
  			yaffs_gross_lock(dev);
  			goto out;
  		}
  		yaffs_gross_lock(dev);
  		offset++;
  		f->f_pos++;
  	}
  
  	curoffs = 1;
  
  	/* If the directory has changed since the open or last call to
  	   readdir, rewind to after the 2 canned entries. */
  	if (f->f_version != inode->i_version) {
  		offset = 2;
  		f->f_pos = offset;
  		f->f_version = inode->i_version;
  	}
  
  	while(sc->nextReturn){
  		curoffs++;
                  l = sc->nextReturn;
  		if (curoffs >= offset) {
                          int this_inode = yaffs_get_obj_inode(l);
                          int this_type = yaffs_get_obj_type(l);
  
  			yaffs_get_obj_name(l, name,
  					    YAFFS_MAX_NAME_LENGTH + 1);
  			T(YAFFS_TRACE_OS,
  			  (TSTR("yaffs_readdir: %s inode %d\n"),
  			  name, yaffs_get_obj_inode(l)));
  
                          yaffs_gross_unlock(dev);
  
  			if (filldir(dirent,
  					name,
  					strlen(name),
  					offset,
  					this_inode,
  					this_type) < 0){
  				yaffs_gross_lock(dev);
  				goto out;
  			}
  
                          yaffs_gross_lock(dev);
  
  			offset++;
  			f->f_pos++;
  		}
                  yaffs_search_advance(sc);
  	}
  
  out:
  	yaffs_search_end(sc);
  	yaffs_dev_to_lc(dev)->readdirProcess = NULL;
  	yaffs_gross_unlock(dev);
  
  	return retVal;
  }
  
  
  
  /*
   * File creation. Allocate an inode, and we're done..
   */
  
  #if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 29)
  #define YCRED(x) x
  #else
  #define YCRED(x) (x->cred)
  #endif
  
  #if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 5, 0))
  static int yaffs_mknod(struct inode *dir, struct dentry *dentry, int mode,
  			dev_t rdev)
  #else
  static int yaffs_mknod(struct inode *dir, struct dentry *dentry, int mode,
  			int rdev)
  #endif
  {
  	struct inode *inode;
  
  	yaffs_obj_t *obj = NULL;
  	yaffs_dev_t *dev;
  
  	yaffs_obj_t *parent = yaffs_InodeToObject(dir);
  
  	int error = -ENOSPC;
  	uid_t uid = YCRED(current)->fsuid;
  	gid_t gid = (dir->i_mode & S_ISGID) ? dir->i_gid : YCRED(current)->fsgid;
  
  	if ((dir->i_mode & S_ISGID) && S_ISDIR(mode))
  		mode |= S_ISGID;
  
  	if (parent) {
  		T(YAFFS_TRACE_OS,
  			(TSTR("yaffs_mknod: parent object %d type %d\n"),
  			parent->obj_id, parent->variant_type));
  	} else {
  		T(YAFFS_TRACE_OS,
  			(TSTR("yaffs_mknod: could not get parent object\n")));
  		return -EPERM;
  	}
  
  	T(YAFFS_TRACE_OS, (TSTR("yaffs_mknod: making oject for %s, "
  			"mode %x dev %x\n"),
  			dentry->d_name.name, mode, rdev));
  
  	dev = parent->my_dev;
  
  	yaffs_gross_lock(dev);
  
  	switch (mode & S_IFMT) {
  	default:
  		/* Special (socket, fifo, device...) */
  		T(YAFFS_TRACE_OS, (TSTR("yaffs_mknod: making special\n")));
  #if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 5, 0))
  		obj = yaffs_create_special(parent, dentry->d_name.name, mode, uid,
  				gid, old_encode_dev(rdev));
  #else
  		obj = yaffs_create_special(parent, dentry->d_name.name, mode, uid,
  				gid, rdev);
  #endif
  		break;
  	case S_IFREG:		/* file          */
  		T(YAFFS_TRACE_OS, (TSTR("yaffs_mknod: making file\n")));
  		obj = yaffs_create_file(parent, dentry->d_name.name, mode, uid,
  				gid);
  		break;
  	case S_IFDIR:		/* directory */
  		T(YAFFS_TRACE_OS,
  			(TSTR("yaffs_mknod: making directory\n")));
  		obj = yaffs_create_dir(parent, dentry->d_name.name, mode,
  					uid, gid);
  		break;
  	case S_IFLNK:		/* symlink */
  		T(YAFFS_TRACE_OS, (TSTR("yaffs_mknod: making symlink\n")));
  		obj = NULL;	/* Do we ever get here? */
  		break;
  	}
  
  	/* Can not call yaffs_get_inode() with gross lock held */
  	yaffs_gross_unlock(dev);
  
  	if (obj) {
  		inode = yaffs_get_inode(dir->i_sb, mode, rdev, obj);
  		d_instantiate(dentry, inode);
  		update_dir_time(dir);
  		T(YAFFS_TRACE_OS,
  			(TSTR("yaffs_mknod created object %d count = %d\n"),
  			obj->obj_id, atomic_read(&inode->i_count)));
  		error = 0;
  		yaffs_fill_inode_from_obj(dir,parent);
  	} else {
  		T(YAFFS_TRACE_OS,
  			(TSTR("yaffs_mknod failed making object\n")));
  		error = -ENOMEM;
  	}
  
  	return error;
  }
  
  static int yaffs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
  {
  	int retVal;
  	T(YAFFS_TRACE_OS, (TSTR("yaffs_mkdir\n")));
  	retVal = yaffs_mknod(dir, dentry, mode | S_IFDIR, 0);
  	return retVal;
  }
  
  #if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 5, 0))
  static int yaffs_create(struct inode *dir, struct dentry *dentry, int mode,
  			struct nameidata *n)
  #else
  static int yaffs_create(struct inode *dir, struct dentry *dentry, int mode)
  #endif
  {
  	T(YAFFS_TRACE_OS,(TSTR("yaffs_create\n")));
  	return yaffs_mknod(dir, dentry, mode | S_IFREG, 0);
  }
  
  static int yaffs_unlink(struct inode *dir, struct dentry *dentry)
  {
  	int retVal;
  
  	yaffs_dev_t *dev;
  	yaffs_obj_t *obj;
  
  	T(YAFFS_TRACE_OS,
  		(TSTR("yaffs_unlink %d:%s\n"),
  		(int)(dir->i_ino),
  		dentry->d_name.name));
  	obj = yaffs_InodeToObject(dir);
  	dev = obj->my_dev;
  
  	yaffs_gross_lock(dev);
  
  	retVal = yaffs_unlinker(obj, dentry->d_name.name);
  
  	if (retVal == YAFFS_OK) {
  		dentry->d_inode->i_nlink--;
  		dir->i_version++;
  		yaffs_gross_unlock(dev);
  		mark_inode_dirty(dentry->d_inode);
  		update_dir_time(dir);
  		return 0;
  	}
  	yaffs_gross_unlock(dev);
  	return -ENOTEMPTY;
  }
  
  /*
   * Create a link...
   */
  static int yaffs_link(struct dentry *old_dentry, struct inode *dir,
  			struct dentry *dentry)
  {
  	struct inode *inode = old_dentry->d_inode;
  	yaffs_obj_t *obj = NULL;
  	yaffs_obj_t *link = NULL;
  	yaffs_dev_t *dev;
  
  	T(YAFFS_TRACE_OS, (TSTR("yaffs_link\n")));
  
  	obj = yaffs_InodeToObject(inode);
  	dev = obj->my_dev;
  
  	yaffs_gross_lock(dev);
  
  	if (!S_ISDIR(inode->i_mode))		/* Don't link directories */
  		link = yaffs_link_obj(yaffs_InodeToObject(dir), dentry->d_name.name,
  			obj);
  
  	if (link) {
  		old_dentry->d_inode->i_nlink = yaffs_get_obj_link_count(obj);
  		d_instantiate(dentry, old_dentry->d_inode);
  		atomic_inc(&old_dentry->d_inode->i_count);
  		T(YAFFS_TRACE_OS,
  			(TSTR("yaffs_link link count %d i_count %d\n"),
  			old_dentry->d_inode->i_nlink,
  			atomic_read(&old_dentry->d_inode->i_count)));
  	}
  
  	yaffs_gross_unlock(dev);
  
  	if (link){
  		update_dir_time(dir);
  		return 0;
  	}
  
  	return -EPERM;
  }
  
  static int yaffs_symlink(struct inode *dir, struct dentry *dentry,
  				const char *symname)
  {
  	yaffs_obj_t *obj;
  	yaffs_dev_t *dev;
  	uid_t uid = YCRED(current)->fsuid;
  	gid_t gid = (dir->i_mode & S_ISGID) ? dir->i_gid : YCRED(current)->fsgid;
  
  	T(YAFFS_TRACE_OS, (TSTR("yaffs_symlink\n")));
  
  	dev = yaffs_InodeToObject(dir)->my_dev;
  	yaffs_gross_lock(dev);
  	obj = yaffs_create_symlink(yaffs_InodeToObject(dir), dentry->d_name.name,
  				S_IFLNK | S_IRWXUGO, uid, gid, symname);
  	yaffs_gross_unlock(dev);
  
  	if (obj) {
  		struct inode *inode;
  
  		inode = yaffs_get_inode(dir->i_sb, obj->yst_mode, 0, obj);
  		d_instantiate(dentry, inode);
  		update_dir_time(dir);
  		T(YAFFS_TRACE_OS, (TSTR("symlink created OK\n")));
  		return 0;
  	} else {
  		T(YAFFS_TRACE_OS, (TSTR("symlink not created\n")));
  	}
  
  	return -ENOMEM;
  }
  
  #if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 34))
  static int yaffs_sync_object(struct file *file, int datasync)
  #else
  static int yaffs_sync_object(struct file *file, struct dentry *dentry,
  				int datasync)
  #endif
  {
  
  	yaffs_obj_t *obj;
  	yaffs_dev_t *dev;
  #if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 34))
  	struct dentry *dentry = file->f_path.dentry;
  #endif
  
  	obj = yaffs_dentry_to_obj(dentry);
  
  	dev = obj->my_dev;
  
  	T(YAFFS_TRACE_OS | YAFFS_TRACE_SYNC,
  		(TSTR("yaffs_sync_object\n")));
  	yaffs_gross_lock(dev);
  	yaffs_flush_file(obj, 1, datasync);
  	yaffs_gross_unlock(dev);
  	return 0;
  }
  
  /*
   * The VFS layer already does all the dentry stuff for rename.
   *
   * NB: POSIX says you can rename an object over an old object of the same name
   */
  static int yaffs_rename(struct inode *old_dir, struct dentry *old_dentry,
  			struct inode *new_dir, struct dentry *new_dentry)
  {
  	yaffs_dev_t *dev;
  	int retVal = YAFFS_FAIL;
  	yaffs_obj_t *target;
  
  	T(YAFFS_TRACE_OS, (TSTR("yaffs_rename\n")));
  	dev = yaffs_InodeToObject(old_dir)->my_dev;
  
  	yaffs_gross_lock(dev);
  
  	/* Check if the target is an existing directory that is not empty. */
  	target = yaffs_find_by_name(yaffs_InodeToObject(new_dir),
  				new_dentry->d_name.name);
  
  
  
  	if (target && target->variant_type == YAFFS_OBJECT_TYPE_DIRECTORY &&
  		!ylist_empty(&target->variant.dir_variant.children)) {
  
  		T(YAFFS_TRACE_OS, (TSTR("target is non-empty dir\n")));
  
  		retVal = YAFFS_FAIL;
  	} else {
  		/* Now does unlinking internally using shadowing mechanism */
  		T(YAFFS_TRACE_OS, (TSTR("calling yaffs_rename_obj\n")));
  
  		retVal = yaffs_rename_obj(yaffs_InodeToObject(old_dir),
  				old_dentry->d_name.name,
  				yaffs_InodeToObject(new_dir),
  				new_dentry->d_name.name);
  	}
  	yaffs_gross_unlock(dev);
  
  	if (retVal == YAFFS_OK) {
  		if (target) {
  			new_dentry->d_inode->i_nlink--;
  			mark_inode_dirty(new_dentry->d_inode);
  		}
  		
  		update_dir_time(old_dir);
  		if(old_dir != new_dir)
  			update_dir_time(new_dir);
  		return 0;
  	} else {
  		return -ENOTEMPTY;
  	}
  }
  
  static int yaffs_setattr(struct dentry *dentry, struct iattr *attr)
  {
  	struct inode *inode = dentry->d_inode;
  	int error = 0;
  	yaffs_dev_t *dev;
  
  	T(YAFFS_TRACE_OS,
  		(TSTR("yaffs_setattr of object %d\n"),
  		yaffs_InodeToObject(inode)->obj_id));
  
  	/* Fail if a requested resize >= 2GB */		
  	if (attr->ia_valid & ATTR_SIZE &&
  		(attr->ia_size >> 31))
  		error = -EINVAL;
  
  	if (error == 0)
  		error = inode_change_ok(inode, attr);
  	if (error == 0) {
  		int result;
  		if (!error){
  			error = yaffs_vfs_setattr(inode, attr);
  			T(YAFFS_TRACE_OS,(TSTR("inode_setattr called\n")));
  			if (attr->ia_valid & ATTR_SIZE){
                          	yaffs_vfs_setsize(inode,attr->ia_size);
                          	inode->i_blocks = (inode->i_size + 511) >> 9;
  			}
  		}
  		dev = yaffs_InodeToObject(inode)->my_dev;
  		if (attr->ia_valid & ATTR_SIZE){
  			T(YAFFS_TRACE_OS,(TSTR("resize to %d(%x)\n"),
  				(int)(attr->ia_size),(int)(attr->ia_size)));
  		}
  		yaffs_gross_lock(dev);
  		result = yaffs_set_attribs(yaffs_InodeToObject(inode), attr);
  		if(result == YAFFS_OK) {
  			error = 0;
  		} else {
  			error = -EPERM;
  		}
  		yaffs_gross_unlock(dev);
  
  	}
  
  	T(YAFFS_TRACE_OS,
  		(TSTR("yaffs_setattr done returning %d\n"),error));
  
  	return error;
  }
  
  #ifdef CONFIG_YAFFS_XATTR
  int yaffs_setxattr(struct dentry *dentry, const char *name,
  			const void *value, size_t size, int flags)
  {
  	struct inode *inode = dentry->d_inode;
  	int error = 0;
  	yaffs_dev_t *dev;
  	yaffs_obj_t *obj = yaffs_InodeToObject(inode);
  
  	T(YAFFS_TRACE_OS,
  		(TSTR("yaffs_setxattr of object %d\n"),
  		obj->obj_id));
  
  
  	if (error == 0) {
  		int result;
  		dev = obj->my_dev;
  		yaffs_gross_lock(dev);
  		result = yaffs_set_xattrib(obj, name, value, size, flags);
  		if(result == YAFFS_OK)
  			error = 0;
  		else if(result < 0)
  			error = result;
  		yaffs_gross_unlock(dev);
  
  	}
  	T(YAFFS_TRACE_OS,
  		(TSTR("yaffs_setxattr done returning %d\n"),error));
  
  	return error;
  }
  
  
  ssize_t yaffs_getxattr(struct dentry *dentry, const char *name, void *buff,
  			size_t size)
  {
  	struct inode *inode = dentry->d_inode;
  	int error = 0;
  	yaffs_dev_t *dev;
  	yaffs_obj_t *obj = yaffs_InodeToObject(inode);
  
  	T(YAFFS_TRACE_OS,
  		(TSTR("yaffs_getxattr \"%s\" from object %d\n"),
  		name, obj->obj_id));
  
  	if (error == 0) {
  		dev = obj->my_dev;
  		yaffs_gross_lock(dev);
  		error = yaffs_get_xattrib(obj, name, buff, size);
  		yaffs_gross_unlock(dev);
  
  	}
  	T(YAFFS_TRACE_OS,
  		(TSTR("yaffs_getxattr done returning %d\n"),error));
  
  	return error;
  }
  
  int yaffs_removexattr(struct dentry *dentry, const char *name)
  {
  	struct inode *inode = dentry->d_inode;
  	int error = 0;
  	yaffs_dev_t *dev;
  	yaffs_obj_t *obj = yaffs_InodeToObject(inode);
  
  	T(YAFFS_TRACE_OS,
  		(TSTR("yaffs_removexattr of object %d\n"),
  		obj->obj_id));
  
  
  	if (error == 0) {
  		int result;
  		dev = obj->my_dev;
  		yaffs_gross_lock(dev);
  		result = yaffs_remove_xattrib(obj, name);
  		if(result == YAFFS_OK)
  			error = 0;
  		else if(result < 0)
  			error = result;
  		yaffs_gross_unlock(dev);
  
  	}
  	T(YAFFS_TRACE_OS,
  		(TSTR("yaffs_removexattr done returning %d\n"),error));
  
  	return error;
  }
  
  ssize_t yaffs_listxattr(struct dentry *dentry, char *buff, size_t size)
  {
  	struct inode *inode = dentry->d_inode;
  	int error = 0;
  	yaffs_dev_t *dev;
  	yaffs_obj_t *obj = yaffs_InodeToObject(inode);
  
  	T(YAFFS_TRACE_OS,
  		(TSTR("yaffs_listxattr of object %d\n"),
  		obj->obj_id));
  
  
  	if (error == 0) {
  		dev = obj->my_dev;
  		yaffs_gross_lock(dev);
  		error = yaffs_list_xattrib(obj, buff, size);
  		yaffs_gross_unlock(dev);
  
  	}
  	T(YAFFS_TRACE_OS,
  		(TSTR("yaffs_listxattr done returning %d\n"),error));
  
  	return error;
  }
  
  #endif
  
  
  #if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 17))
  static int yaffs_statfs(struct dentry *dentry, struct kstatfs *buf)
  {
  	yaffs_dev_t *dev = yaffs_dentry_to_obj(dentry)->my_dev;
  	struct super_block *sb = dentry->d_sb;
  #elif (LINUX_VERSION_CODE > KERNEL_VERSION(2, 5, 0))
  static int yaffs_statfs(struct super_block *sb, struct kstatfs *buf)
  {
  	yaffs_dev_t *dev = yaffs_SuperToDevice(sb);
  #else
  static int yaffs_statfs(struct super_block *sb, struct statfs *buf)
  {
  	yaffs_dev_t *dev = yaffs_SuperToDevice(sb);
  #endif
  
  	T(YAFFS_TRACE_OS, (TSTR("yaffs_statfs\n")));
  
  	yaffs_gross_lock(dev);
  
  	buf->f_type = YAFFS_MAGIC;
  	buf->f_bsize = sb->s_blocksize;
  	buf->f_namelen = 255;
  
  	if (dev->data_bytes_per_chunk & (dev->data_bytes_per_chunk - 1)) {
  		/* Do this if chunk size is not a power of 2 */
  
  		uint64_t bytesInDev;
  		uint64_t bytesFree;
  
  		bytesInDev = ((uint64_t)((dev->param.end_block - dev->param.start_block + 1))) *
  			((uint64_t)(dev->param.chunks_per_block * dev->data_bytes_per_chunk));
  
  		do_div(bytesInDev, sb->s_blocksize); /* bytesInDev becomes the number of blocks */
  		buf->f_blocks = bytesInDev;
  
  		bytesFree  = ((uint64_t)(yaffs_get_n_free_chunks(dev))) *
  			((uint64_t)(dev->data_bytes_per_chunk));
  
  		do_div(bytesFree, sb->s_blocksize);
  
  		buf->f_bfree = bytesFree;
  
  	} else if (sb->s_blocksize > dev->data_bytes_per_chunk) {
  
  		buf->f_blocks =
  			(dev->param.end_block - dev->param.start_block + 1) *
  			dev->param.chunks_per_block /
  			(sb->s_blocksize / dev->data_bytes_per_chunk);
  		buf->f_bfree =
  			yaffs_get_n_free_chunks(dev) /
  			(sb->s_blocksize / dev->data_bytes_per_chunk);
  	} else {
  		buf->f_blocks =
  			(dev->param.end_block - dev->param.start_block + 1) *
  			dev->param.chunks_per_block *
  			(dev->data_bytes_per_chunk / sb->s_blocksize);
  
  		buf->f_bfree =
  			yaffs_get_n_free_chunks(dev) *
  			(dev->data_bytes_per_chunk / sb->s_blocksize);
  	}
  
  	buf->f_files = 0;
  	buf->f_ffree = 0;
  	buf->f_bavail = buf->f_bfree;
  
  	yaffs_gross_unlock(dev);
  	return 0;
  }
  
  
  
  static void yaffs_flush_inodes(struct super_block *sb)
  {
  	struct inode *iptr;
  	yaffs_obj_t *obj;
  	
  	list_for_each_entry(iptr,&sb->s_inodes, i_sb_list){
  		obj = yaffs_InodeToObject(iptr);
  		if(obj){
  			T(YAFFS_TRACE_OS, (TSTR("flushing obj %d\n"),
  				obj->obj_id));
  			yaffs_flush_file(obj,1,0);
  		}
  	}
  }
  
  
  static void yaffs_flush_super(struct super_block *sb, int do_checkpoint)
  {
  	yaffs_dev_t *dev = yaffs_SuperToDevice(sb);	
  	if(!dev)
  		return;
  	
  	yaffs_flush_inodes(sb);
  	yaffs_update_dirty_dirs(dev);
  	yaffs_flush_whole_cache(dev);
  	if(do_checkpoint)
  		yaffs_checkpoint_save(dev);
  }
  
  
  static unsigned yaffs_bg_gc_urgency(yaffs_dev_t *dev)
  {
  	unsigned erasedChunks = dev->n_erased_blocks * dev->param.chunks_per_block;
  	struct yaffs_LinuxContext *context = yaffs_dev_to_lc(dev);
  	unsigned scatteredFree = 0; /* Free chunks not in an erased block */
  
  	if(erasedChunks < dev->n_free_chunks)
  		scatteredFree = (dev->n_free_chunks - erasedChunks);
  
  	if(!context->bgRunning)
  		return 0;
  	else if(scatteredFree < (dev->param.chunks_per_block * 2))
  		return 0;
  	else if(erasedChunks > dev->n_free_chunks/2)
  		return 0;
  	else if(erasedChunks > dev->n_free_chunks/4)
  		return 1;
  	else
  		return 2;
  }
  
  static int yaffs_do_sync_fs(struct super_block *sb,
  				int request_checkpoint)
  {
  
  	yaffs_dev_t *dev = yaffs_SuperToDevice(sb);
  	unsigned int oneshot_checkpoint = (yaffs_auto_checkpoint & 4);
  	unsigned gc_urgent = yaffs_bg_gc_urgency(dev);
  	int do_checkpoint;
  
  	T(YAFFS_TRACE_OS | YAFFS_TRACE_SYNC | YAFFS_TRACE_BACKGROUND,
  		(TSTR("yaffs_do_sync_fs: gc-urgency %d %s %s%s\n"),
  		gc_urgent,
  		sb->s_dirt ? "dirty" : "clean",
  		request_checkpoint ? "checkpoint requested" : "no checkpoint",
  		oneshot_checkpoint ? " one-shot" : "" ));
  
  	yaffs_gross_lock(dev);
  	do_checkpoint = ((request_checkpoint && !gc_urgent) ||
  			oneshot_checkpoint) &&
  			!dev->is_checkpointed;
  
  	if (sb->s_dirt || do_checkpoint) {
  		yaffs_flush_super(sb, !dev->is_checkpointed && do_checkpoint);
  		sb->s_dirt = 0;
  		if(oneshot_checkpoint)
  			yaffs_auto_checkpoint &= ~4;
  	}
  	yaffs_gross_unlock(dev);
  
  	return 0;
  }
  
  /*
   * yaffs background thread functions .
   * yaffs_bg_thread_fn() the thread function
   * yaffs_bg_start() launches the background thread.
   * yaffs_bg_stop() cleans up the background thread.
   *
   * NB: 
   * The thread should only run after the yaffs is initialised
   * The thread should be stopped before yaffs is unmounted.
   * The thread should not do any writing while the fs is in read only.
   */
  
  #ifdef YAFFS_COMPILE_BACKGROUND
  
  void yaffs_background_waker(unsigned long data)
  {
  	wake_up_process((struct task_struct *)data);
  }
  
  static int yaffs_bg_thread_fn(void *data)
  {
  	yaffs_dev_t *dev = (yaffs_dev_t *)data;
  	struct yaffs_LinuxContext *context = yaffs_dev_to_lc(dev);
  	unsigned long now = jiffies;
  	unsigned long next_dir_update = now;
  	unsigned long next_gc = now;
  	unsigned long expires;
  	unsigned int urgency;
  
  	int gcResult;
  	struct timer_list timer;
  
  	T(YAFFS_TRACE_BACKGROUND,
  		(TSTR("yaffs_background starting for dev %p\n"),
  		(void *)dev));
  
  #ifdef YAFFS_COMPILE_FREEZER
  	set_freezable();
  #endif
  	while(context->bgRunning){
  		T(YAFFS_TRACE_BACKGROUND,
  			(TSTR("yaffs_background\n")));
  
  		if(kthread_should_stop())
  			break;
  
  #ifdef YAFFS_COMPILE_FREEZER
  		if(try_to_freeze())
  			continue;
  #endif
  		yaffs_gross_lock(dev);
  
  		now = jiffies;
  
  		if(time_after(now, next_dir_update) && yaffs_bg_enable){
  			yaffs_update_dirty_dirs(dev);
  			next_dir_update = now + HZ;
  		}
  
  		if(time_after(now,next_gc) && yaffs_bg_enable){
  			if(!dev->is_checkpointed){
  				urgency = yaffs_bg_gc_urgency(dev);
  				gcResult = yaffs_bg_gc(dev, urgency);
  				if(urgency > 1)
  					next_gc = now + HZ/20+1;
  				else if(urgency > 0)
  					next_gc = now + HZ/10+1;
  				else
  					next_gc = now + HZ * 2;
  			} else /*
  				* gc not running so set to next_dir_update
  				* to cut down on wake ups
  				*/
  				next_gc = next_dir_update;
  		}
  		yaffs_gross_unlock(dev);
  #if 1
  		expires = next_dir_update;
  		if (time_before(next_gc,expires))
  			expires = next_gc;
  		if(time_before(expires,now))
  			expires = now + HZ;
  
  		Y_INIT_TIMER(&timer);
  		timer.expires = expires+1;
  		timer.data = (unsigned long) current;
  		timer.function = yaffs_background_waker;
  
                  set_current_state(TASK_INTERRUPTIBLE);
  		add_timer(&timer);
  		schedule();
  		del_timer_sync(&timer);
  #else
  		msleep(10);
  #endif
  	}
  
  	return 0;
  }
  
  static int yaffs_bg_start(yaffs_dev_t *dev)
  {
  	int retval = 0;
  	struct yaffs_LinuxContext *context = yaffs_dev_to_lc(dev);
  
  	if(dev->read_only)
  		return -1;
  
  	context->bgRunning = 1;
  
  	context->bgThread = kthread_run(yaffs_bg_thread_fn,
  	                        (void *)dev,"yaffs-bg-%d",context->mount_id);
  
  	if(IS_ERR(context->bgThread)){
  		retval = PTR_ERR(context->bgThread);
  		context->bgThread = NULL;
  		context->bgRunning = 0;
  	}
  	return retval;
  }
  
  static void yaffs_bg_stop(yaffs_dev_t *dev)
  {
  	struct yaffs_LinuxContext *ctxt = yaffs_dev_to_lc(dev);
  
  	ctxt->bgRunning = 0;
  
  	if( ctxt->bgThread){
  		kthread_stop(ctxt->bgThread);
  		ctxt->bgThread = NULL;
  	}
  }
  #else
  static int yaffs_bg_thread_fn(void *data)
  {
  	return 0;
  }
  
  static int yaffs_bg_start(yaffs_dev_t *dev)
  {
  	return 0;
  }
  
  static void yaffs_bg_stop(yaffs_dev_t *dev)
  {
  }
  #endif
  
  
  #if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 17))
  static void yaffs_write_super(struct super_block *sb)
  #else
  static int yaffs_write_super(struct super_block *sb)
  #endif
  {
  	unsigned request_checkpoint = (yaffs_auto_checkpoint >= 2);
  
  	T(YAFFS_TRACE_OS | YAFFS_TRACE_SYNC | YAFFS_TRACE_BACKGROUND,
  		(TSTR("yaffs_write_super%s\n"),
  		request_checkpoint ? " checkpt" : ""));
  
  	yaffs_do_sync_fs(sb, request_checkpoint);
  
  #if (LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 18))
  	return 0;
  #endif
  }
  
  
  #if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 17))
  static int yaffs_sync_fs(struct super_block *sb, int wait)
  #else
  static int yaffs_sync_fs(struct super_block *sb)
  #endif
  {
  	unsigned request_checkpoint = (yaffs_auto_checkpoint >= 1);
  
  	T(YAFFS_TRACE_OS | YAFFS_TRACE_SYNC,
  		(TSTR("yaffs_sync_fs%s\n"),
  		request_checkpoint ? " checkpt" : ""));
  
  	yaffs_do_sync_fs(sb, request_checkpoint);
  
  	return 0;
  }
  
  #ifdef YAFFS_USE_OWN_IGET
  
  static struct inode *yaffs_iget(struct super_block *sb, unsigned long ino)
  {
  	struct inode *inode;
  	yaffs_obj_t *obj;
  	yaffs_dev_t *dev = yaffs_SuperToDevice(sb);
  
  	T(YAFFS_TRACE_OS,
  		(TSTR("yaffs_iget for %lu\n"), ino));
  
  	inode = iget_locked(sb, ino);
  	if (!inode)
  		return ERR_PTR(-ENOMEM);
  	if (!(inode->i_state & I_NEW))
  		return inode;
  
  	/* NB This is called as a side effect of other functions, but
  	 * we had to release the lock to prevent deadlocks, so
  	 * need to lock again.
  	 */
  
  	yaffs_gross_lock(dev);
  
  	obj = yaffs_find_by_number(dev, inode->i_ino);
  
  	yaffs_fill_inode_from_obj(inode, obj);
  
  	yaffs_gross_unlock(dev);
  
  	unlock_new_inode(inode);
  	return inode;
  }
  
  #else
  
  static void yaffs_read_inode(struct inode *inode)
  {
  	/* NB This is called as a side effect of other functions, but
  	 * we had to release the lock to prevent deadlocks, so
  	 * need to lock again.
  	 */
  
  	yaffs_obj_t *obj;
  	yaffs_dev_t *dev = yaffs_SuperToDevice(inode->i_sb);
  
  	T(YAFFS_TRACE_OS,
  		(TSTR("yaffs_read_inode for %d\n"), (int)inode->i_ino));
  
  	if(current != yaffs_dev_to_lc(dev)->readdirProcess)
  		yaffs_gross_lock(dev);
  
  	obj = yaffs_find_by_number(dev, inode->i_ino);
  
  	yaffs_fill_inode_from_obj(inode, obj);
  
  	if(current != yaffs_dev_to_lc(dev)->readdirProcess)
  		yaffs_gross_unlock(dev);
  }
  
  #endif
  
  static YLIST_HEAD(yaffs_context_list);
  struct semaphore yaffs_context_lock;
  
  static void yaffs_put_super(struct super_block *sb)
  {
  	yaffs_dev_t *dev = yaffs_SuperToDevice(sb);
  
  	T(YAFFS_TRACE_OS, (TSTR("yaffs_put_super\n")));
  
  	T(YAFFS_TRACE_OS | YAFFS_TRACE_BACKGROUND,
  		(TSTR("Shutting down yaffs background thread\n")));
  	yaffs_bg_stop(dev);
  	T(YAFFS_TRACE_OS | YAFFS_TRACE_BACKGROUND,
  		(TSTR("yaffs background thread shut down\n")));
  
  	yaffs_gross_lock(dev);
  
  	yaffs_flush_super(sb,1);
  
  	if (yaffs_dev_to_lc(dev)->putSuperFunc)
  		yaffs_dev_to_lc(dev)->putSuperFunc(sb);
  
  
  	yaffs_deinitialise(dev);
  
  	yaffs_gross_unlock(dev);
  
  	down(&yaffs_context_lock);
  	ylist_del_init(&(yaffs_dev_to_lc(dev)->contextList));
  	up(&yaffs_context_lock);
  
  	if (yaffs_dev_to_lc(dev)->spareBuffer) {
  		YFREE(yaffs_dev_to_lc(dev)->spareBuffer);
  		yaffs_dev_to_lc(dev)->spareBuffer = NULL;
  	}
  
  	kfree(dev);
  }
  
  
  static void yaffs_MTDPutSuper(struct super_block *sb)
  {
  	struct mtd_info *mtd = yaffs_dev_to_mtd(yaffs_SuperToDevice(sb));
  
  	if (mtd->sync)
  		mtd->sync(mtd);
  
  	put_mtd_device(mtd);
  }
  
  
  static void yaffs_touch_super(yaffs_dev_t *dev)
  {
  	struct super_block *sb = yaffs_dev_to_lc(dev)->superBlock;
  
  	T(YAFFS_TRACE_OS, (TSTR("yaffs_touch_super() sb = %p\n"), sb));
  	if (sb)
  		sb->s_dirt = 1;
  }
  
  typedef struct {
  	int inband_tags;
  	int skip_checkpoint_read;
  	int skip_checkpoint_write;
  	int no_cache;
  	int tags_ecc_on;
  	int tags_ecc_overridden;
  	int lazy_loading_enabled;
  	int lazy_loading_overridden;
  	int empty_lost_and_found;
  	int empty_lost_and_found_overridden;
  } yaffs_options;
  
  #define MAX_OPT_LEN 30
  static int yaffs_parse_options(yaffs_options *options, const char *options_str)
  {
  	char cur_opt[MAX_OPT_LEN + 1];
  	int p;
  	int error = 0;
  
  	/* Parse through the options which is a comma seperated list */
  
  	while (options_str && *options_str && !error) {
  		memset(cur_opt, 0, MAX_OPT_LEN + 1);
  		p = 0;
  
  		while(*options_str == ',')
  			options_str++;
  
  		while (*options_str && *options_str != ',') {
  			if (p < MAX_OPT_LEN) {
  				cur_opt[p] = *options_str;
  				p++;
  			}
  			options_str++;
  		}
  
  		if (!strcmp(cur_opt, "inband-tags"))
  			options->inband_tags = 1;
  		else if (!strcmp(cur_opt, "tags-ecc-off")){
  			options->tags_ecc_on = 0;
  			options->tags_ecc_overridden=1;
  		} else if (!strcmp(cur_opt, "tags-ecc-on")){
  			options->tags_ecc_on = 1;
  			options->tags_ecc_overridden = 1;
  		} else if (!strcmp(cur_opt, "lazy-loading-off")){
  			options->lazy_loading_enabled = 0;
  			options->lazy_loading_overridden=1;
  		} else if (!strcmp(cur_opt, "lazy-loading-on")){
  			options->lazy_loading_enabled = 1;
  			options->lazy_loading_overridden = 1;
  		} else if (!strcmp(cur_opt, "empty-lost-and-found-off")){
  			options->empty_lost_and_found = 0;
  			options->empty_lost_and_found_overridden=1;
  		} else if (!strcmp(cur_opt, "empty-lost-and-found-on")){
  			options->empty_lost_and_found = 1;
  			options->empty_lost_and_found_overridden=1;
  		} else if (!strcmp(cur_opt, "no-cache"))
  			options->no_cache = 1;
  		else if (!strcmp(cur_opt, "no-checkpoint-read"))
  			options->skip_checkpoint_read = 1;
  		else if (!strcmp(cur_opt, "no-checkpoint-write"))
  			options->skip_checkpoint_write = 1;
  		else if (!strcmp(cur_opt, "no-checkpoint")) {
  			options->skip_checkpoint_read = 1;
  			options->skip_checkpoint_write = 1;
  		} else {
  			printk(KERN_INFO "yaffs: Bad mount option \"%s\"\n",
  					cur_opt);
  			error = 1;
  		}
  	}
  
  	return error;
  }
  
  static struct super_block *yaffs_internal_read_super(int yaffs_version,
  						struct super_block *sb,
  						void *data, int silent)
  {
  	int nBlocks;
  	struct inode *inode = NULL;
  	struct dentry *root;
  	yaffs_dev_t *dev = 0;
  	char devname_buf[BDEVNAME_SIZE + 1];
  	struct mtd_info *mtd;
  	int err;
  	char *data_str = (char *)data;
  	struct yaffs_LinuxContext *context = NULL;
  	yaffs_param_t *param;
  
  	int read_only = 0;
  
  	yaffs_options options;
  
  	unsigned mount_id;
  	int found;
  	struct yaffs_LinuxContext *context_iterator;
  	struct ylist_head *l;
  
  	sb->s_magic = YAFFS_MAGIC;
  	sb->s_op = &yaffs_super_ops;
  	sb->s_flags |= MS_NOATIME;
  
  	read_only =((sb->s_flags & MS_RDONLY) != 0);
  
  
  #ifdef YAFFS_COMPILE_EXPORTFS
  	sb->s_export_op = &yaffs_export_ops;
  #endif
  
  	if (!sb)
  		printk(KERN_INFO "yaffs: sb is NULL\n");
  	else if (!sb->s_dev)
  		printk(KERN_INFO "yaffs: sb->s_dev is NULL\n");
  	else if (!yaffs_devname(sb, devname_buf))
  		printk(KERN_INFO "yaffs: devname is NULL\n");
  	else
  		printk(KERN_INFO "yaffs: dev is %d name is \"%s\" %s\n",
  		       sb->s_dev,
  		       yaffs_devname(sb, devname_buf),
  		       read_only ? "ro" : "rw");
  
  	if (!data_str)
  		data_str = "";
  
  	printk(KERN_INFO "yaffs: passed flags \"%s\"\n", data_str);
  
  	memset(&options, 0, sizeof(options));
  
  	if (yaffs_parse_options(&options, data_str)) {
  		/* Option parsing failed */
  		return NULL;
  	}
  
  
  	sb->s_blocksize = PAGE_CACHE_SIZE;
  	sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
  
  	T(YAFFS_TRACE_OS,
  		(TSTR("yaffs_read_super: Using yaffs%d\n"), yaffs_version));
  	T(YAFFS_TRACE_OS,
  		(TSTR("yaffs_read_super: block size %d\n"),
  		(int)(sb->s_blocksize)));
  
  	T(YAFFS_TRACE_ALWAYS,
  		(TSTR("yaffs: Attempting MTD mount of %u.%u,\"%s\"\n"),
  	       MAJOR(sb->s_dev), MINOR(sb->s_dev),
  	       yaffs_devname(sb, devname_buf)));
  
  	/* Check it's an mtd device..... */
  	if (MAJOR(sb->s_dev) != MTD_BLOCK_MAJOR)
  		return NULL;	/* This isn't an mtd device */
  
  	/* Get the device */
  	mtd = get_mtd_device(NULL, MINOR(sb->s_dev));
  	if (!mtd) {
  		T(YAFFS_TRACE_ALWAYS,
  			(TSTR("yaffs: MTD device #%u doesn't appear to exist\n"),
  			MINOR(sb->s_dev)));
  		return NULL;
  	}
  	/* Check it's NAND */
  	if (mtd->type != MTD_NANDFLASH) {
  		T(YAFFS_TRACE_ALWAYS,
  			(TSTR("yaffs: MTD device is not NAND it's type %d\n"),
  			mtd->type));
  		return NULL;
  	}
  
  	T(YAFFS_TRACE_OS, (TSTR(" erase %p\n"), mtd->erase));
  	T(YAFFS_TRACE_OS, (TSTR(" read %p\n"), mtd->read));
  	T(YAFFS_TRACE_OS, (TSTR(" write %p\n"), mtd->write));
  	T(YAFFS_TRACE_OS, (TSTR(" readoob %p\n"), mtd->read_oob));
  	T(YAFFS_TRACE_OS, (TSTR(" writeoob %p\n"), mtd->write_oob));
  	T(YAFFS_TRACE_OS, (TSTR(" block_isbad %p\n"), mtd->block_isbad));
  	T(YAFFS_TRACE_OS, (TSTR(" block_markbad %p\n"), mtd->block_markbad));
  	T(YAFFS_TRACE_OS, (TSTR(" %s %d\n"), WRITE_SIZE_STR, WRITE_SIZE(mtd)));
  	T(YAFFS_TRACE_OS, (TSTR(" oobsize %d\n"), mtd->oobsize));
  	T(YAFFS_TRACE_OS, (TSTR(" erasesize %d\n"), mtd->erasesize));
  #if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 29)
  	T(YAFFS_TRACE_OS, (TSTR(" size %u\n"), mtd->size));
  #else
  	T(YAFFS_TRACE_OS, (TSTR(" size %lld\n"), mtd->size));
  #endif
  
  #ifdef CONFIG_YAFFS_AUTO_YAFFS2
  
  	if (yaffs_version == 1 && WRITE_SIZE(mtd) >= 2048) {
  		T(YAFFS_TRACE_ALWAYS,
  			(TSTR("yaffs: auto selecting yaffs2\n")));
  		yaffs_version = 2;
  	}
  
  	/* Added NCB 26/5/2006 for completeness */
  	if (yaffs_version == 2 && !options.inband_tags && WRITE_SIZE(mtd) == 512) {
  		T(YAFFS_TRACE_ALWAYS,
  			(TSTR("yaffs: auto selecting yaffs1\n")));
  		yaffs_version = 1;
  	}
  
  #endif
  
  	if (yaffs_version == 2) {
  		/* Check for version 2 style functions */
  		if (!mtd->erase ||
  		    !mtd->block_isbad ||
  		    !mtd->block_markbad ||
  		    !mtd->read ||
  		    !mtd->write ||
  #if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 17))
  		    !mtd->read_oob || !mtd->write_oob) {
  #else
  		    !mtd->write_ecc ||
  		    !mtd->read_ecc || !mtd->read_oob || !mtd->write_oob) {
  #endif
  			T(YAFFS_TRACE_ALWAYS,
  			  (TSTR("yaffs: MTD device does not support required "
  			   "functions\n")));
  			return NULL;
  		}
  
  		if ((WRITE_SIZE(mtd) < YAFFS_MIN_YAFFS2_CHUNK_SIZE ||
  		    mtd->oobsize < YAFFS_MIN_YAFFS2_SPARE_SIZE) &&
  		    !options.inband_tags) {
  			T(YAFFS_TRACE_ALWAYS,
  			  (TSTR("yaffs: MTD device does not have the "
  			   "right page sizes\n")));
  			return NULL;
  		}
  	} else {
  		/* Check for V1 style functions */
  		if (!mtd->erase ||
  		    !mtd->read ||
  		    !mtd->write ||
  #if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 17))
  		    !mtd->read_oob || !mtd->write_oob) {
  #else
  		    !mtd->write_ecc ||
  		    !mtd->read_ecc || !mtd->read_oob || !mtd->write_oob) {
  #endif
  			T(YAFFS_TRACE_ALWAYS,
  			  (TSTR("yaffs: MTD device does not support required "
  			   "functions\n")));
  			return NULL;
  		}
  
  		if (WRITE_SIZE(mtd) < YAFFS_BYTES_PER_CHUNK ||
  		    mtd->oobsize != YAFFS_BYTES_PER_SPARE) {
  			T(YAFFS_TRACE_ALWAYS,
  			  (TSTR("yaffs: MTD device does not support have the "
  			   "right page sizes\n")));
  			return NULL;
  		}
  	}
  
  	/* OK, so if we got here, we have an MTD that's NAND and looks
  	 * like it has the right capabilities
  	 * Set the yaffs_dev_t up for mtd
  	 */
  
  	if (!read_only && !(mtd->flags & MTD_WRITEABLE)){
  		read_only = 1;
  		printk(KERN_INFO "yaffs: mtd is read only, setting superblock read only");
  		sb->s_flags |= MS_RDONLY;
  	}
  
  	dev = kmalloc(sizeof(yaffs_dev_t), GFP_KERNEL);
  	context = kmalloc(sizeof(struct yaffs_LinuxContext),GFP_KERNEL);
  	
  	if(!dev || !context ){
  		if(dev)
  			kfree(dev);
  		if(context)
  			kfree(context);
  		dev = NULL;
  		context = NULL;
  	}
  
  	if (!dev) {
  		/* Deep shit could not allocate device structure */
  		T(YAFFS_TRACE_ALWAYS,
  		  (TSTR("yaffs_read_super: Failed trying to allocate "
  		   "yaffs_dev_t. \n")));
  		return NULL;
  	}
  	memset(dev, 0, sizeof(yaffs_dev_t));
  	param = &(dev->param);
  
  	memset(context,0,sizeof(struct yaffs_LinuxContext));
  	dev->os_context = context;
  	YINIT_LIST_HEAD(&(context->contextList));
  	context->dev = dev;
  	context->superBlock = sb;
  
  	dev->read_only = read_only;
  
  #if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 5, 0))
  	sb->s_fs_info = dev;
  #else
  	sb->u.generic_sbp = dev;
  #endif
  	
  	dev->driver_context = mtd;
  	param->name = mtd->name;
  
  	/* Set up the memory size parameters.... */
  
  	nBlocks = YCALCBLOCKS(mtd->size, (YAFFS_CHUNKS_PER_BLOCK * YAFFS_BYTES_PER_CHUNK));
  
  	param->start_block = 0;
  	param->end_block = nBlocks - 1;
  	param->chunks_per_block = YAFFS_CHUNKS_PER_BLOCK;
  	param->total_bytes_per_chunk = YAFFS_BYTES_PER_CHUNK;
  	param->n_reserved_blocks = 5;
  	param->n_caches = (options.no_cache) ? 0 : 10;
  	param->inband_tags = options.inband_tags;
  
  #ifdef CONFIG_YAFFS_DISABLE_LAZY_LOAD
  	param->disable_lazy_load = 1;
  #endif
  #ifdef CONFIG_YAFFS_XATTR
  	param->enable_xattr = 1;
  #endif
  	if(options.lazy_loading_overridden)
  		param->disable_lazy_load = !options.lazy_loading_enabled;
  
  #ifdef CONFIG_YAFFS_DISABLE_TAGS_ECC
  	param->no_tags_ecc = 1;
  #endif
  
  #ifdef CONFIG_YAFFS_DISABLE_BACKGROUND
  #else
  	param->defered_dir_update = 1;
  #endif
  
  	if(options.tags_ecc_overridden)
  		param->no_tags_ecc = !options.tags_ecc_on;
  
  #ifdef CONFIG_YAFFS_EMPTY_LOST_AND_FOUND
  	param->empty_lost_n_found = 1;
  #endif
  
  #ifdef CONFIG_YAFFS_DISABLE_BLOCK_REFRESHING
  	param->refresh_period = 0;
  #else
  	param->refresh_period = 500;
  #endif
  
  #ifdef CONFIG_YAFFS__ALWAYS_CHECK_CHUNK_ERASED
  	param->always_check_erased = 1;
  #endif
  
  	if(options.empty_lost_and_found_overridden)
  		param->empty_lost_n_found = options.empty_lost_and_found;
  
  	/* ... and the functions. */
  	if (yaffs_version == 2) {
  		param->write_chunk_tags_fn =
  		    nandmtd2_WriteChunkWithTagsToNAND;
  		param->read_chunk_tags_fn =
  		    nandmtd2_ReadChunkWithTagsFromNAND;
  		param->bad_block_fn = nandmtd2_MarkNANDBlockBad;
  		param->query_block_fn = nandmtd2_QueryNANDBlock;
  		yaffs_dev_to_lc(dev)->spareBuffer = YMALLOC(mtd->oobsize);
  		param->is_yaffs2 = 1;
  #if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 17))
  		param->total_bytes_per_chunk = mtd->writesize;
  		param->chunks_per_block = mtd->erasesize / mtd->writesize;
  #else
  		param->total_bytes_per_chunk = mtd->oobblock;
  		param->chunks_per_block = mtd->erasesize / mtd->oobblock;
  #endif
  		nBlocks = YCALCBLOCKS(mtd->size, mtd->erasesize);
  
  		param->start_block = 0;
  		param->end_block = nBlocks - 1;
  	} else {
  #if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 17))
  		/* use the MTD interface in yaffs_mtdif1.c */
  		param->write_chunk_tags_fn =
  			nandmtd1_WriteChunkWithTagsToNAND;
  		param->read_chunk_tags_fn =
  			nandmtd1_ReadChunkWithTagsFromNAND;
  		param->bad_block_fn = nandmtd1_MarkNANDBlockBad;
  		param->query_block_fn = nandmtd1_QueryNANDBlock;
  #else
  		param->write_chunk_fn = nandmtd_WriteChunkToNAND;
  		param->read_chunk_fn = nandmtd_ReadChunkFromNAND;
  #endif
  		param->is_yaffs2 = 0;
  	}
  	/* ... and common functions */
  	param->erase_fn = nandmtd_EraseBlockInNAND;
  	param->initialise_flash_fn = nandmtd_InitialiseNAND;
  
  	yaffs_dev_to_lc(dev)->putSuperFunc = yaffs_MTDPutSuper;
  
  	param->sb_dirty_fn = yaffs_touch_super;
  	param->gc_control = yaffs_gc_control_callback;
  
  	yaffs_dev_to_lc(dev)->superBlock= sb;
  	
  
  #ifndef CONFIG_YAFFS_DOES_ECC
  	param->use_nand_ecc = 1;
  #endif
  
  #ifdef CONFIG_YAFFS_DISABLE_WIDE_TNODES
  	param->wide_tnodes_disabled = 1;
  #endif
  
  	param->skip_checkpt_rd = options.skip_checkpoint_read;
  	param->skip_checkpt_wr = options.skip_checkpoint_write;
  
  	down(&yaffs_context_lock);
  	/* Get a mount id */
  	found = 0;
  	for(mount_id=0; ! found; mount_id++){
  		found = 1;
  		ylist_for_each(l,&yaffs_context_list){
  			context_iterator = ylist_entry(l,struct yaffs_LinuxContext,contextList);
  			if(context_iterator->mount_id == mount_id)
  				found = 0;
  		}
  	}
  	context->mount_id = mount_id;
  
  	ylist_add_tail(&(yaffs_dev_to_lc(dev)->contextList), &yaffs_context_list);
  	up(&yaffs_context_lock);
  
          /* Directory search handling...*/
          YINIT_LIST_HEAD(&(yaffs_dev_to_lc(dev)->searchContexts));
          param->remove_obj_fn = yaffs_remove_obj_callback;
  
  	init_MUTEX(&(yaffs_dev_to_lc(dev)->grossLock));
  
  	yaffs_gross_lock(dev);
  
  	err = yaffs_guts_initialise(dev);
  
  	T(YAFFS_TRACE_OS,
  	  (TSTR("yaffs_read_super: guts initialised %s\n"),
  	   (err == YAFFS_OK) ? "OK" : "FAILED"));
  	   
  	if(err == YAFFS_OK)
  		yaffs_bg_start(dev);
  		
  	if(!context->bgThread)
  		param->defered_dir_update = 0;
  
  
  	/* Release lock before yaffs_get_inode() */
  	yaffs_gross_unlock(dev);
  
  	/* Create root inode */
  	if (err == YAFFS_OK)
  		inode = yaffs_get_inode(sb, S_IFDIR | 0755, 0,
  					yaffs_root(dev));
  
  	if (!inode)
  		return NULL;
  
  	inode->i_op = &yaffs_dir_inode_operations;
  	inode->i_fop = &yaffs_dir_operations;
  
  	T(YAFFS_TRACE_OS, (TSTR("yaffs_read_super: got root inode\n")));
  
  	root = d_alloc_root(inode);
  
  	T(YAFFS_TRACE_OS, (TSTR("yaffs_read_super: d_alloc_root done\n")));
  
  	if (!root) {
  		iput(inode);
  		return NULL;
  	}
  	sb->s_root = root;
  	sb->s_dirt = !dev->is_checkpointed;
  	T(YAFFS_TRACE_ALWAYS,
  		(TSTR("yaffs_read_super: is_checkpointed %d\n"),
  		dev->is_checkpointed));
  
  	T(YAFFS_TRACE_OS, (TSTR("yaffs_read_super: done\n")));
  	return sb;
  }
  
  
  #if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 5, 0))
  static int yaffs_internal_read_super_mtd(struct super_block *sb, void *data,
  					 int silent)
  {
  	return yaffs_internal_read_super(1, sb, data, silent) ? 0 : -EINVAL;
  }
  
  #if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 17))
  static int yaffs_read_super(struct file_system_type *fs,
  			    int flags, const char *dev_name,
  			    void *data, struct vfsmount *mnt)
  {
  
  	return get_sb_bdev(fs, flags, dev_name, data,
  			   yaffs_internal_read_super_mtd, mnt);
  }
  #else
  static struct super_block *yaffs_read_super(struct file_system_type *fs,
  					    int flags, const char *dev_name,
  					    void *data)
  {
  
  	return get_sb_bdev(fs, flags, dev_name, data,
  			   yaffs_internal_read_super_mtd);
  }
  #endif
  
  static struct file_system_type yaffs_fs_type = {
  	.owner = THIS_MODULE,
  	.name = "yaffs",
  	.get_sb = yaffs_read_super,
  	.kill_sb = kill_block_super,
  	.fs_flags = FS_REQUIRES_DEV,
  };
  #else
  static struct super_block *yaffs_read_super(struct super_block *sb, void *data,
  					    int silent)
  {
  	return yaffs_internal_read_super(1, sb, data, silent);
  }
  
  static DECLARE_FSTYPE(yaffs_fs_type, "yaffs", yaffs_read_super,
  		      FS_REQUIRES_DEV);
  #endif
  
  
  #ifdef CONFIG_YAFFS_YAFFS2
  
  #if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 5, 0))
  static int yaffs2_internal_read_super_mtd(struct super_block *sb, void *data,
  					  int silent)
  {
  	return yaffs_internal_read_super(2, sb, data, silent) ? 0 : -EINVAL;
  }
  
  #if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 17))
  static int yaffs2_read_super(struct file_system_type *fs,
  			int flags, const char *dev_name, void *data,
  			struct vfsmount *mnt)
  {
  	return get_sb_bdev(fs, flags, dev_name, data,
  			yaffs2_internal_read_super_mtd, mnt);
  }
  #else
  static struct super_block *yaffs2_read_super(struct file_system_type *fs,
  					     int flags, const char *dev_name,
  					     void *data)
  {
  
  	return get_sb_bdev(fs, flags, dev_name, data,
  			   yaffs2_internal_read_super_mtd);
  }
  #endif
  
  static struct file_system_type yaffs2_fs_type = {
  	.owner = THIS_MODULE,
  	.name = "yaffs2",
  	.get_sb = yaffs2_read_super,
  	.kill_sb = kill_block_super,
  	.fs_flags = FS_REQUIRES_DEV,
  };
  #else
  static struct super_block *yaffs2_read_super(struct super_block *sb,
  					     void *data, int silent)
  {
  	return yaffs_internal_read_super(2, sb, data, silent);
  }
  
  static DECLARE_FSTYPE(yaffs2_fs_type, "yaffs2", yaffs2_read_super,
  		      FS_REQUIRES_DEV);
  #endif
  
  #endif				/* CONFIG_YAFFS_YAFFS2 */
  
  static struct proc_dir_entry *my_proc_entry;
  static struct proc_dir_entry *debug_proc_entry;
  
  static char *yaffs_dump_dev_part0(char *buf, yaffs_dev_t * dev)
  {
  	buf += sprintf(buf, "start_block.......... %d\n", dev->param.start_block);
  	buf += sprintf(buf, "end_block............ %d\n", dev->param.end_block);
  	buf += sprintf(buf, "total_bytes_per_chunk %d\n", dev->param.total_bytes_per_chunk);
  	buf += sprintf(buf, "use_nand_ecc......... %d\n", dev->param.use_nand_ecc);
  	buf += sprintf(buf, "no_tags_ecc.......... %d\n", dev->param.no_tags_ecc);
  	buf += sprintf(buf, "is_yaffs2............ %d\n", dev->param.is_yaffs2);
  	buf += sprintf(buf, "inband_tags.......... %d\n", dev->param.inband_tags);
  	buf += sprintf(buf, "empty_lost_n_found... %d\n", dev->param.empty_lost_n_found);
  	buf += sprintf(buf, "disable_lazy_load.... %d\n", dev->param.disable_lazy_load);
  	buf += sprintf(buf, "refresh_period....... %d\n", dev->param.refresh_period);
  	buf += sprintf(buf, "n_caches............. %d\n", dev->param.n_caches);
  	buf += sprintf(buf, "n_reserved_blocks.... %d\n", dev->param.n_reserved_blocks);
  	buf += sprintf(buf, "always_check_erased.. %d\n", dev->param.always_check_erased);
  
  	buf += sprintf(buf, "\n");
  
  	return buf;
  }
  
  
  static char *yaffs_dump_dev_part1(char *buf, yaffs_dev_t * dev)
  {
  	buf += sprintf(buf, "data_bytes_per_chunk. %d\n", dev->data_bytes_per_chunk);
  	buf += sprintf(buf, "chunk_grp_bits....... %d\n", dev->chunk_grp_bits);
  	buf += sprintf(buf, "chunk_grp_size....... %d\n", dev->chunk_grp_size);
  	buf += sprintf(buf, "n_erased_blocks...... %d\n", dev->n_erased_blocks);
  	buf += sprintf(buf, "blocks_in_checkpt.... %d\n", dev->blocks_in_checkpt);
  	buf += sprintf(buf, "\n");
  	buf += sprintf(buf, "n_tnodes............. %d\n", dev->n_tnodes);
  	buf += sprintf(buf, "n_obj................ %d\n", dev->n_obj);
  	buf += sprintf(buf, "n_free_chunks........ %d\n", dev->n_free_chunks);
  	buf += sprintf(buf, "\n");
  	buf += sprintf(buf, "n_page_writes........ %u\n", dev->n_page_writes);
  	buf += sprintf(buf, "n_page_reads......... %u\n", dev->n_page_reads);
  	buf += sprintf(buf, "n_erasures........... %u\n", dev->n_erasures);
  	buf += sprintf(buf, "n_gc_copies.......... %u\n", dev->n_gc_copies);
  	buf += sprintf(buf, "all_gcs.............. %u\n", dev->all_gcs);
  	buf += sprintf(buf, "passive_gc_count..... %u\n", dev->passive_gc_count);
  	buf += sprintf(buf, "oldest_dirty_gc_count %u\n", dev->oldest_dirty_gc_count);
  	buf += sprintf(buf, "n_gc_blocks.......... %u\n", dev->n_gc_blocks);
  	buf += sprintf(buf, "bg_gcs............... %u\n", dev->bg_gcs);
  	buf += sprintf(buf, "n_retired_writes..... %u\n", dev->n_retired_writes);
  	buf += sprintf(buf, "nRetireBlocks........ %u\n", dev->n_retired_blocks);
  	buf += sprintf(buf, "n_ecc_fixed.......... %u\n", dev->n_ecc_fixed);
  	buf += sprintf(buf, "n_ecc_unfixed........ %u\n", dev->n_ecc_unfixed);
  	buf += sprintf(buf, "n_tags_ecc_fixed..... %u\n", dev->n_tags_ecc_fixed);
  	buf += sprintf(buf, "n_tags_ecc_unfixed... %u\n", dev->n_tags_ecc_unfixed);
  	buf += sprintf(buf, "cache_hits........... %u\n", dev->cache_hits);
  	buf += sprintf(buf, "n_deleted_files...... %u\n", dev->n_deleted_files);
  	buf += sprintf(buf, "n_unlinked_files..... %u\n", dev->n_unlinked_files);
  	buf += sprintf(buf, "refresh_count........ %u\n", dev->refresh_count);
  	buf += sprintf(buf, "n_bg_deletions....... %u\n", dev->n_bg_deletions);
  
  	return buf;
  }
  
  static int yaffs_proc_read(char *page,
  			   char **start,
  			   off_t offset, int count, int *eof, void *data)
  {
  	struct ylist_head *item;
  	char *buf = page;
  	int step = offset;
  	int n = 0;
  
  	/* Get proc_file_read() to step 'offset' by one on each sucessive call.
  	 * We use 'offset' (*ppos) to indicate where we are in dev_list.
  	 * This also assumes the user has posted a read buffer large
  	 * enough to hold the complete output; but that's life in /proc.
  	 */
  
  	*(int *)start = 1;
  
  	/* Print header first */
  	if (step == 0)
  		buf += sprintf(buf, "Multi-version YAFFS built:" __DATE__ " " __TIME__"\n");
  	else if (step == 1)
  		buf += sprintf(buf,"\n");
  	else {
  		step-=2;
  		
  		down(&yaffs_context_lock);
  
  		/* Locate and print the Nth entry.  Order N-squared but N is small. */
  		ylist_for_each(item, &yaffs_context_list) {
  			struct yaffs_LinuxContext *dc = ylist_entry(item, struct yaffs_LinuxContext, contextList);
  			yaffs_dev_t *dev = dc->dev;
  
  			if (n < (step & ~1)) {
  				n+=2;
  				continue;
  			}
  			if((step & 1)==0){
  				buf += sprintf(buf, "\nDevice %d \"%s\"\n", n, dev->param.name);
  				buf = yaffs_dump_dev_part0(buf, dev);
  			} else
  				buf = yaffs_dump_dev_part1(buf, dev);
  			
  			break;
  		}
  		up(&yaffs_context_lock);
  	}
  
  	return buf - page < count ? buf - page : count;
  }
  
  static int yaffs_stats_proc_read(char *page,
  				char **start,
  				off_t offset, int count, int *eof, void *data)
  {
  	struct ylist_head *item;
  	char *buf = page;
  	int n = 0;
  
  	down(&yaffs_context_lock);
  
  	/* Locate and print the Nth entry.  Order N-squared but N is small. */
  	ylist_for_each(item, &yaffs_context_list) {
  		struct yaffs_LinuxContext *dc = ylist_entry(item, struct yaffs_LinuxContext, contextList);
  		yaffs_dev_t *dev = dc->dev;
  
  		int erasedChunks;
  
  		erasedChunks = dev->n_erased_blocks * dev->param.chunks_per_block;
  		
  		buf += sprintf(buf,"%d, %d, %d, %u, %u, %u, %u\n",
  				n, dev->n_free_chunks, erasedChunks,
  				dev->bg_gcs, dev->oldest_dirty_gc_count,
  				dev->n_obj, dev->n_tnodes);
  	}
  	up(&yaffs_context_lock);
  
  
  	return buf - page < count ? buf - page : count;
  }
  
  /**
   * Set the verbosity of the warnings and error messages.
   *
   * Note that the names can only be a..z or _ with the current code.
   */
  
  static struct {
  	char *mask_name;
  	unsigned mask_bitfield;
  } mask_flags[] = {
  	{"allocate", YAFFS_TRACE_ALLOCATE},
  	{"always", YAFFS_TRACE_ALWAYS},
  	{"background", YAFFS_TRACE_BACKGROUND},
  	{"bad_blocks", YAFFS_TRACE_BAD_BLOCKS},
  	{"buffers", YAFFS_TRACE_BUFFERS},
  	{"bug", YAFFS_TRACE_BUG},
  	{"checkpt", YAFFS_TRACE_CHECKPOINT},
  	{"deletion", YAFFS_TRACE_DELETION},
  	{"erase", YAFFS_TRACE_ERASE},
  	{"error", YAFFS_TRACE_ERROR},
  	{"gc_detail", YAFFS_TRACE_GC_DETAIL},
  	{"gc", YAFFS_TRACE_GC},
  	{"lock", YAFFS_TRACE_LOCK},
  	{"mtd", YAFFS_TRACE_MTD},
  	{"nandaccess", YAFFS_TRACE_NANDACCESS},
  	{"os", YAFFS_TRACE_OS},
  	{"scan_debug", YAFFS_TRACE_SCAN_DEBUG},
  	{"scan", YAFFS_TRACE_SCAN},
  	{"tracing", YAFFS_TRACE_TRACING},
  	{"sync", YAFFS_TRACE_SYNC},
  	{"write", YAFFS_TRACE_WRITE},
  
  	{"verify", YAFFS_TRACE_VERIFY},
  	{"verify_nand", YAFFS_TRACE_VERIFY_NAND},
  	{"verify_full", YAFFS_TRACE_VERIFY_FULL},
  	{"verify_all", YAFFS_TRACE_VERIFY_ALL},
  
  	{"all", 0xffffffff},
  	{"none", 0},
  	{NULL, 0},
  };
  
  #define MAX_MASK_NAME_LENGTH 40
  static int yaffs_proc_write_trace_options(struct file *file, const char *buf,
  					 unsigned long count, void *data)
  {
  	unsigned rg = 0, mask_bitfield;
  	char *end;
  	char *mask_name;
  	const char *x;
  	char substring[MAX_MASK_NAME_LENGTH + 1];
  	int i;
  	int done = 0;
  	int add, len = 0;
  	int pos = 0;
  
  	rg = yaffs_trace_mask;
  
  	while (!done && (pos < count)) {
  		done = 1;
  		while ((pos < count) && isspace(buf[pos]))
  			pos++;
  
  		switch (buf[pos]) {
  		case '+':
  		case '-':
  		case '=':
  			add = buf[pos];
  			pos++;
  			break;
  
  		default:
  			add = ' ';
  			break;
  		}
  		mask_name = NULL;
  
  		mask_bitfield = simple_strtoul(buf + pos, &end, 0);
  
  		if (end > buf + pos) {
  			mask_name = "numeral";
  			len = end - (buf + pos);
  			pos += len;
  			done = 0;
  		} else {
  			for (x = buf + pos, i = 0;
  			    (*x == '_' || (*x >= 'a' && *x <= 'z')) &&
  			    i < MAX_MASK_NAME_LENGTH; x++, i++, pos++)
  				substring[i] = *x;
  			substring[i] = '\0';
  
  			for (i = 0; mask_flags[i].mask_name != NULL; i++) {
  				if (strcmp(substring, mask_flags[i].mask_name) == 0) {
  					mask_name = mask_flags[i].mask_name;
  					mask_bitfield = mask_flags[i].mask_bitfield;
  					done = 0;
  					break;
  				}
  			}
  		}
  
  		if (mask_name != NULL) {
  			done = 0;
  			switch (add) {
  			case '-':
  				rg &= ~mask_bitfield;
  				break;
  			case '+':
  				rg |= mask_bitfield;
  				break;
  			case '=':
  				rg = mask_bitfield;
  				break;
  			default:
  				rg |= mask_bitfield;
  				break;
  			}
  		}
  	}
  
  	yaffs_trace_mask = rg | YAFFS_TRACE_ALWAYS;
  
  	printk(KERN_DEBUG "new trace = 0x%08X\n", yaffs_trace_mask);
  
  	if (rg & YAFFS_TRACE_ALWAYS) {
  		for (i = 0; mask_flags[i].mask_name != NULL; i++) {
  			char flag;
  			flag = ((rg & mask_flags[i].mask_bitfield) ==
  				mask_flags[i].mask_bitfield) ? '+' : '-';
  			printk(KERN_DEBUG "%c%s\n", flag, mask_flags[i].mask_name);
  		}
  	}
  
  	return count;
  }
  
  
  static int yaffs_proc_write(struct file *file, const char *buf,
  					 unsigned long count, void *data)
  {
          return yaffs_proc_write_trace_options(file, buf, count, data);
  }
  
  /* Stuff to handle installation of file systems */
  struct file_system_to_install {
  	struct file_system_type *fst;
  	int installed;
  };
  
  static struct file_system_to_install fs_to_install[] = {
  	{&yaffs_fs_type, 0},
  	{&yaffs2_fs_type, 0},
  	{NULL, 0}
  };
  
  static int __init init_yaffs_fs(void)
  {
  	int error = 0;
  	struct file_system_to_install *fsinst;
  
  	T(YAFFS_TRACE_ALWAYS,
  	  (TSTR("yaffs built " __DATE__ " " __TIME__ " Installing. \n")));
  
  #ifdef CONFIG_YAFFS_ALWAYS_CHECK_CHUNK_ERASED
  	T(YAFFS_TRACE_ALWAYS,
  	  (TSTR(" \n\n\n\nYAFFS-WARNING CONFIG_YAFFS_ALWAYS_CHECK_CHUNK_ERASED selected.\n\n\n\n")));
  #endif
  
  
  
  
  	init_MUTEX(&yaffs_context_lock);
  
  	/* Install the proc_fs entries */
  	my_proc_entry = create_proc_entry("yaffs",
  					       S_IRUGO | S_IFREG,
  					       YPROC_ROOT);
  
  	if (my_proc_entry) {
  		my_proc_entry->write_proc = yaffs_proc_write;
  		my_proc_entry->read_proc = yaffs_proc_read;
  		my_proc_entry->data = NULL;
  	} else
  		return -ENOMEM;
  
  	debug_proc_entry = create_proc_entry("yaffs_stats",
  					       S_IRUGO | S_IFREG,
  					       YPROC_ROOT);
  
  	if (debug_proc_entry) {
  		debug_proc_entry->write_proc = NULL;
  		debug_proc_entry->read_proc = yaffs_stats_proc_read;
  		debug_proc_entry->data = NULL;
  	} else
  		return -ENOMEM;
  
  	/* Now add the file system entries */
  
  	fsinst = fs_to_install;
  
  	while (fsinst->fst && !error) {
  		error = register_filesystem(fsinst->fst);
  		if (!error)
  			fsinst->installed = 1;
  		fsinst++;
  	}
  
  	/* Any errors? uninstall  */
  	if (error) {
  		fsinst = fs_to_install;
  
  		while (fsinst->fst) {
  			if (fsinst->installed) {
  				unregister_filesystem(fsinst->fst);
  				fsinst->installed = 0;
  			}
  			fsinst++;
  		}
  	}
  
  	return error;
  }
  
  static void __exit exit_yaffs_fs(void)
  {
  
  	struct file_system_to_install *fsinst;
  
  	T(YAFFS_TRACE_ALWAYS,
  		(TSTR("yaffs built " __DATE__ " " __TIME__ " removing. \n")));
  
  	remove_proc_entry("yaffs", YPROC_ROOT);
  	remove_proc_entry("yaffs_stats", YPROC_ROOT);
  
  	fsinst = fs_to_install;
  
  	while (fsinst->fst) {
  		if (fsinst->installed) {
  			unregister_filesystem(fsinst->fst);
  			fsinst->installed = 0;
  		}
  		fsinst++;
  	}
  }
  
  module_init(init_yaffs_fs)
  module_exit(exit_yaffs_fs)
  
  MODULE_DESCRIPTION("YAFFS2 - a NAND specific flash file system");
  MODULE_AUTHOR("Charles Manning, Aleph One Ltd., 2002-2010");
  MODULE_LICENSE("GPL");
  