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yaffs_vfs_glue.c
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yaffs_vfs_glue.c
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/*
* 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 <[email protected]>
* 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_Device associated with
* this superblock
* >> 2.6: sb->s_fs_info points to the yaffs_Device associated with this
* superblock
* >> inode->u.generic_ip points to the associated yaffs_Object.
*/
/*
* 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"
#include "yaffs_crypto.h"
#include "yaffs_pbkdf2.h"
#include "yaffs_packedtags2.h"
unsigned int yaffs_traceMask = 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_traceMask, 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_traceMask, "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_Object *)(yaffs_InodeToObjectLV(iptr)))
#define yaffs_DentryToObject(dptr) yaffs_InodeToObject((dptr)->d_inode)
#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 5, 0))
#define yaffs_SuperToDevice(sb) ((yaffs_Device *)sb->s_fs_info)
#else
#define yaffs_SuperToDevice(sb) ((yaffs_Device *)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_MarkSuperBlockDirty(yaffs_Device *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_Device *dev)
{
return yaffs_gc_control;
}
static void yaffs_GrossLock(yaffs_Device *dev)
{
T(YAFFS_TRACE_LOCK, (TSTR("yaffs locking %p\n"), current));
down(&(yaffs_DeviceToLC(dev)->grossLock));
T(YAFFS_TRACE_LOCK, (TSTR("yaffs locked %p\n"), current));
}
static void yaffs_GrossUnlock(yaffs_Device *dev)
{
T(YAFFS_TRACE_LOCK, (TSTR("yaffs unlocking %p\n"), current));
up(&(yaffs_DeviceToLC(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_Object *d_obj;
yaffs_Object *parent_obj;
d_obj = yaffs_InodeToObject(dentry->d_inode);
if (d_obj) {
parent_obj = d_obj->parent;
if (parent_obj) {
parent_ino = yaffs_GetObjectInode(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 removeObjectCallback 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_Device 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_Device *dev;
yaffs_Object *dirObj;
yaffs_Object *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_Object *dir)
{
yaffs_Device *dev = dir->myDev;
struct yaffs_SearchContext *sc = YMALLOC(sizeof(struct yaffs_SearchContext));
if(sc){
sc->dirObj = dir;
sc->dev = dev;
if( ylist_empty(&sc->dirObj->variant.directoryVariant.children))
sc->nextReturn = NULL;
else
sc->nextReturn = ylist_entry(
dir->variant.directoryVariant.children.next,
yaffs_Object,siblings);
YINIT_LIST_HEAD(&sc->others);
ylist_add(&sc->others,&(yaffs_DeviceToLC(dev)->searchContexts));
}
return sc;
}
/*
* yaffs_EndSearch() disposes of a search context and cleans up.
*/
static void yaffs_EndSearch(struct yaffs_SearchContext * sc)
{
if(sc){
ylist_del(&sc->others);
YFREE(sc);
}
}
/*
* yaffs_SearchAdvance() 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_SearchAdvance(struct yaffs_SearchContext *sc)
{
if(!sc)
return;
if( sc->nextReturn == NULL ||
ylist_empty(&sc->dirObj->variant.directoryVariant.children))
sc->nextReturn = NULL;
else {
struct ylist_head *next = sc->nextReturn->siblings.next;
if( next == &sc->dirObj->variant.directoryVariant.children)
sc->nextReturn = NULL; /* end of list */
else
sc->nextReturn = ylist_entry(next,yaffs_Object,siblings);
}
}
/*
* yaffs_RemoveObjectCallback() 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_RemoveObjectCallback(yaffs_Object *obj)
{
struct ylist_head *i;
struct yaffs_SearchContext *sc;
struct ylist_head *search_contexts = &(yaffs_DeviceToLC(obj->myDev)->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_SearchAdvance(sc);
}
}
}
/*-----------------------------------------------------------------*/
static int yaffs_readlink(struct dentry *dentry, char __user *buffer,
int buflen)
{
unsigned char *alias;
int ret;
yaffs_Device *dev = yaffs_DentryToObject(dentry)->myDev;
yaffs_GrossLock(dev);
alias = yaffs_GetSymlinkAlias(yaffs_DentryToObject(dentry));
yaffs_GrossUnlock(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_Device *dev = yaffs_DentryToObject(dentry)->myDev;
yaffs_GrossLock(dev);
alias = yaffs_GetSymlinkAlias(yaffs_DentryToObject(dentry));
yaffs_GrossUnlock(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_Object *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_Object *obj;
struct inode *inode = NULL; /* NCB 2.5/2.6 needs NULL here */
yaffs_Device *dev = yaffs_InodeToObject(dir)->myDev;
if(current != yaffs_DeviceToLC(dev)->readdirProcess)
yaffs_GrossLock(dev);
T(YAFFS_TRACE_OS,
(TSTR("yaffs_lookup for %d:%s\n"),
yaffs_InodeToObject(dir)->objectId, dentry->d_name.name));
obj = yaffs_FindObjectByName(yaffs_InodeToObject(dir),
dentry->d_name.name);
obj = yaffs_GetEquivalentObject(obj); /* in case it was a hardlink */
/* Can't hold gross lock when calling yaffs_get_inode() */
if(current != yaffs_DeviceToLC(dev)->readdirProcess)
yaffs_GrossUnlock(dev);
if (obj) {
T(YAFFS_TRACE_OS,
(TSTR("yaffs_lookup found %d\n"), obj->objectId));
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_UnstitchObject(struct inode *inode, yaffs_Object *obj)
{
/* Clear the association between the inode and
* the yaffs_Object.
*/
obj->myInode = 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_HandleDeferedFree(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_Object *obj;
yaffs_Device *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->myDev;
yaffs_GrossLock(dev);
yaffs_DeleteObject(obj);
yaffs_GrossUnlock(dev);
}
if (obj) {
dev = obj->myDev;
yaffs_GrossLock(dev);
yaffs_UnstitchObject(inode,obj);
yaffs_GrossUnlock(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_Object *obj;
yaffs_Device *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->myDev;
yaffs_GrossLock(dev);
yaffs_UnstitchObject(inode,obj);
yaffs_GrossUnlock(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_Object *obj = yaffs_InodeToObject(inode);
yaffs_Device *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->myDev;
yaffs_GrossLock(dev);
yaffs_DeleteObject(obj);
yaffs_GrossUnlock(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_Object *obj = yaffs_DentryToObject(file->f_dentry);
yaffs_Device *dev = obj->myDev;
T(YAFFS_TRACE_OS,
(TSTR("yaffs_file_flush object %d (%s)\n"), obj->objectId,
obj->dirty ? "dirty" : "clean"));
yaffs_GrossLock(dev);
yaffs_FlushFile(obj, 1, 0);
yaffs_GrossUnlock(dev);
return 0;
}
static int yaffs_readpage_nolock(struct file *f, struct page *pg)
{
/* Lifted from jffs2 */
yaffs_Object *obj;
unsigned char *pg_buf;
int ret;