yaffs_fs.c

linux 镜像文件制作 用于压制yaffs2类型的文件镜像啊啊啊啊啊啊

	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_Device *dev = yaffs_SuperToDevice(sb);
#else
static int yaffs_statfs(struct super_block *sb, struct statfs *buf)
{
	yaffs_Device *dev = yaffs_SuperToDevice(sb);
#endif

	T(YAFFS_TRACE_OS, ("yaffs_statfs\n"));

	yaffs_GrossLock(dev);

	buf->f_type = YAFFS_MAGIC;
	buf->f_bsize = sb->s_blocksize;
	buf->f_namelen = 255;

	if (dev->nDataBytesPerChunk & (dev->nDataBytesPerChunk - 1)) {
		/* Do this if chunk size is not a power of 2 */

		uint64_t bytesInDev;
		uint64_t bytesFree;

		bytesInDev = ((uint64_t)((dev->endBlock - dev->startBlock + 1))) *
			((uint64_t)(dev->nChunksPerBlock * dev->nDataBytesPerChunk));

		do_div(bytesInDev, sb->s_blocksize); /* bytesInDev becomes the number of blocks */
		buf->f_blocks = bytesInDev;

		bytesFree  = ((uint64_t)(yaffs_GetNumberOfFreeChunks(dev))) *
			((uint64_t)(dev->nDataBytesPerChunk));

		do_div(bytesFree, sb->s_blocksize);

		buf->f_bfree = bytesFree;

	} else if (sb->s_blocksize > dev->nDataBytesPerChunk) {

		buf->f_blocks =
			(dev->endBlock - dev->startBlock + 1) *
			dev->nChunksPerBlock /
			(sb->s_blocksize / dev->nDataBytesPerChunk);
		buf->f_bfree =
			yaffs_GetNumberOfFreeChunks(dev) /
			(sb->s_blocksize / dev->nDataBytesPerChunk);
	} else {
		buf->f_blocks =
			(dev->endBlock - dev->startBlock + 1) *
			dev->nChunksPerBlock *
			(dev->nDataBytesPerChunk / sb->s_blocksize);

		buf->f_bfree =
			yaffs_GetNumberOfFreeChunks(dev) *
			(dev->nDataBytesPerChunk / sb->s_blocksize);
	}

	buf->f_files = 0;
	buf->f_ffree = 0;
	buf->f_bavail = buf->f_bfree;

	yaffs_GrossUnlock(dev);
	return 0;
}


static int yaffs_do_sync_fs(struct super_block *sb)
{

	yaffs_Device *dev = yaffs_SuperToDevice(sb);
	T(YAFFS_TRACE_OS, ("yaffs_do_sync_fs\n"));

	if (sb->s_dirt) {
		yaffs_GrossLock(dev);

		if (dev) {
			yaffs_FlushEntireDeviceCache(dev);
			yaffs_CheckpointSave(dev);
		}

		yaffs_GrossUnlock(dev);

		sb->s_dirt = 0;
	}
	return 0;
}


#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
{

	T(YAFFS_TRACE_OS, ("yaffs_write_super\n"));
	if (yaffs_auto_checkpoint >= 2)
		yaffs_do_sync_fs(sb);
#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
{
	T(YAFFS_TRACE_OS, ("yaffs_sync_fs\n"));

	if (yaffs_auto_checkpoint >= 1)
		yaffs_do_sync_fs(sb);

	return 0;
}

#ifdef YAFFS_USE_OWN_IGET

static struct inode *yaffs_iget(struct super_block *sb, unsigned long ino)
{
	struct inode *inode;
	yaffs_Object *obj;
	yaffs_Device *dev = yaffs_SuperToDevice(sb);

	T(YAFFS_TRACE_OS,
		("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_GrossLock(dev);

	obj = yaffs_FindObjectByNumber(dev, inode->i_ino);

	yaffs_FillInodeFromObject(inode, obj);

	yaffs_GrossUnlock(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_Object *obj;
	yaffs_Device *dev = yaffs_SuperToDevice(inode->i_sb);

	T(YAFFS_TRACE_OS,
		("yaffs_read_inode for %d\n", (int)inode->i_ino));

	yaffs_GrossLock(dev);

	obj = yaffs_FindObjectByNumber(dev, inode->i_ino);

	yaffs_FillInodeFromObject(inode, obj);

	yaffs_GrossUnlock(dev);
}

#endif

static YLIST_HEAD(yaffs_dev_list);

#if 0 /* not used */
static int yaffs_remount_fs(struct super_block *sb, int *flags, char *data)
{
	yaffs_Device    *dev = yaffs_SuperToDevice(sb);

	if (*flags & MS_RDONLY) {
		struct mtd_info *mtd = yaffs_SuperToDevice(sb)->genericDevice;

		T(YAFFS_TRACE_OS,
			("yaffs_remount_fs: %s: RO\n", dev->name));

		yaffs_GrossLock(dev);

		yaffs_FlushEntireDeviceCache(dev);

		yaffs_CheckpointSave(dev);

		if (mtd->sync)
			mtd->sync(mtd);

		yaffs_GrossUnlock(dev);
	} else {
		T(YAFFS_TRACE_OS,
			("yaffs_remount_fs: %s: RW\n", dev->name));
	}

	return 0;
}
#endif

static void yaffs_put_super(struct super_block *sb)
{
	yaffs_Device *dev = yaffs_SuperToDevice(sb);

	T(YAFFS_TRACE_OS, ("yaffs_put_super\n"));

	yaffs_GrossLock(dev);

	yaffs_FlushEntireDeviceCache(dev);

	yaffs_CheckpointSave(dev);

	if (dev->putSuperFunc)
		dev->putSuperFunc(sb);

	yaffs_Deinitialise(dev);

	yaffs_GrossUnlock(dev);

	/* we assume this is protected by lock_kernel() in mount/umount */
	ylist_del(&dev->devList);

	if (dev->spareBuffer) {
		YFREE(dev->spareBuffer);
		dev->spareBuffer = NULL;
	}

	kfree(dev);
}


static void yaffs_MTDPutSuper(struct super_block *sb)
{
	struct mtd_info *mtd = yaffs_SuperToDevice(sb)->genericDevice;

	if (mtd->sync)
		mtd->sync(mtd);

	put_mtd_device(mtd);
}


static void yaffs_MarkSuperBlockDirty(void *vsb)
{
	struct super_block *sb = (struct super_block *)vsb;

	T(YAFFS_TRACE_OS, ("yaffs_MarkSuperBlockDirty() 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;
} yaffs_options;

#define MAX_OPT_LEN 20
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 != ',') {
			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, "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 yaffsVersion,
						struct super_block *sb,
						void *data, int silent)
{
	int nBlocks;
	struct inode *inode = NULL;
	struct dentry *root;
	yaffs_Device *dev = 0;
	char devname_buf[BDEVNAME_SIZE + 1];
	struct mtd_info *mtd;
	int err;
	char *data_str = (char *)data;

	yaffs_options options;

	sb->s_magic = YAFFS_MAGIC;
	sb->s_op = &yaffs_super_ops;
	sb->s_flags |= MS_NOATIME;

	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\"\n",
		       sb->s_dev,
		       yaffs_devname(sb, devname_buf));

	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, ("yaffs_read_super: Using yaffs%d\n", yaffsVersion));
	T(YAFFS_TRACE_OS,
	  ("yaffs_read_super: block size %d\n", (int)(sb->s_blocksize)));

#ifdef CONFIG_YAFFS_DISABLE_WRITE_VERIFY
	T(YAFFS_TRACE_OS,
	  ("yaffs: Write verification disabled. All guarantees "
	   "null and void\n"));
#endif

	T(YAFFS_TRACE_ALWAYS, ("yaffs: Attempting MTD mount on %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,
		  ("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,
		  ("yaffs: MTD device is not NAND it's type %d\n", mtd->type));
		return NULL;
	}

	T(YAFFS_TRACE_OS, (" erase %p\n", mtd->erase));
	T(YAFFS_TRACE_OS, (" read %p\n", mtd->read));
	T(YAFFS_TRACE_OS, (" write %p\n", mtd->write));
	T(YAFFS_TRACE_OS, (" readoob %p\n", mtd->read_oob));
	T(YAFFS_TRACE_OS, (" writeoob %p\n", mtd->write_oob));
	T(YAFFS_TRACE_OS, (" block_isbad %p\n", mtd->block_isbad));
	T(YAFFS_TRACE_OS, (" block_markbad %p\n", mtd->block_markbad));
	T(YAFFS_TRACE_OS, (" %s %d\n", WRITE_SIZE_STR, WRITE_SIZE(mtd)));
	T(YAFFS_TRACE_OS, (" oobsize %d\n", mtd->oobsize));
	T(YAFFS_TRACE_OS, (" erasesize %d\n", mtd->erasesize));
#if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 29)
	T(YAFFS_TRACE_OS, (" size %u\n", mtd->size));
#else
	T(YAFFS_TRACE_OS, (" size %lld\n", mtd->size));
#endif

#ifdef CONFIG_YAFFS_AUTO_YAFFS2

	if (yaffsVersion == 1 && WRITE_SIZE(mtd) >= 2048) {
		T(YAFFS_TRACE_ALWAYS, ("yaffs: auto selecting yaffs2\n"));
		yaffsVersion = 2;
	}

	/* Added NCB 26/5/2006 for completeness */
	if (yaffsVersion == 2 && !options.inband_tags && WRITE_SIZE(mtd) == 512) {
		T(YAFFS_TRACE_ALWAYS, ("yaffs: auto selecting yaffs1\n"));
		yaffsVersion = 1;
	}

#endif

	if (yaffsVersion == 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,
			  ("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,
			  ("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,
			  ("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,
			  ("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_Device up for mtd
	 */

#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 5, 0))
	sb->s_fs_info = dev = kmalloc(sizeof(yaffs_Device), GFP_KERNEL);
#else
	sb->u.generic_sbp = dev = kmalloc(sizeof(yaffs_Device), GFP_KERNEL);
#endif
	if (!dev) {
		/* Deep shit could not allocate device structure */
		T(YAFFS_TRACE_ALWAYS,
		  ("yaffs_read_super: Failed trying to allocate "
		   "yaffs_Device. \n"));
		return NULL;
	}

	memset(dev, 0, sizeof(yaffs_Device));
	dev->genericDevice = mtd;
	dev->name = mtd->name;

	/* Set up the memory size parameters.... */

	nBlocks = YCALCBLOCKS(mtd->size, (YAFFS_CHUNKS_PER_BLOCK * YAFFS_BYTES_PER_CHUNK));

	dev->startBlock = 0;
	dev->endBlock = nBlocks - 1;
	dev->nChunksPerBlock = YAFFS_CHUNKS_PER_BLOCK;
	dev->totalBytesPerChunk = YAFFS_BYTES_PER_CHUNK;
	dev->nReservedBlocks = 5;
	dev->nShortOpCaches = (options.no_cache) ? 0 : 10;