2  * block2mtd.c - create an mtd from a block device
5  * Copyright (C) 2004-2006	Joern Engel <joern@wh.fh-wedel.de>
23 #include <linux/backing-dev.h>
34 /* Maximum number of comma-separated items in the 'block2mtd=' parameter */
58 	struct address_space *mapping = dev->blkdev->bd_inode->i_mapping;  in _block2mtd_erase()
72 			if (*p != -1UL) {  in _block2mtd_erase()
82 		pages--;  in _block2mtd_erase()
89 	struct block2mtd_dev *dev = mtd->priv;  in block2mtd_erase()
90 	size_t from = instr->addr;  in block2mtd_erase()
91 	size_t len = instr->len;  in block2mtd_erase()
94 	mutex_lock(&dev->write_mutex);  in block2mtd_erase()
96 	mutex_unlock(&dev->write_mutex);  in block2mtd_erase()
107 	struct block2mtd_dev *dev = mtd->priv;  in block2mtd_read()
110 	int offset = from & (PAGE_SIZE-1);  in block2mtd_read()
115 			cpylen = PAGE_SIZE - offset;	// multiple pages  in block2mtd_read()
118 		len = len - cpylen;  in block2mtd_read()
120 		page = page_read(dev->blkdev->bd_inode->i_mapping, index);  in block2mtd_read()
142 	struct address_space *mapping = dev->blkdev->bd_inode->i_mapping;  in _block2mtd_write()
149 			cpylen = PAGE_SIZE - offset;	// multiple pages  in _block2mtd_write()
152 		len = len - cpylen;  in _block2mtd_write()
181 	struct block2mtd_dev *dev = mtd->priv;  in block2mtd_write()
184 	mutex_lock(&dev->write_mutex);  in block2mtd_write()
186 	mutex_unlock(&dev->write_mutex);  in block2mtd_write()
193 /* sync the device - wait until the write queue is empty */
196 	struct block2mtd_dev *dev = mtd->priv;  in block2mtd_sync()
197 	sync_blockdev(dev->blkdev);  in block2mtd_sync()
207 	kfree(dev->mtd.name);  in block2mtd_free_device()
209 	if (dev->blkdev) {  in block2mtd_free_device()
210 		invalidate_mapping_pages(dev->blkdev->bd_inode->i_mapping,  in block2mtd_free_device()
211 					0, -1);  in block2mtd_free_device()
212 		blkdev_put(dev->blkdev, NULL);  in block2mtd_free_device()
225 	struct block_device *bdev = ERR_PTR(-ENODEV);  in mdtblock_early_get_bdev()
246 			 * go-arounds.  in mdtblock_early_get_bdev()
284 	dev->blkdev = bdev;  in add_device()
286 	if (MAJOR(bdev->bd_dev) == MTD_BLOCK_MAJOR) {  in add_device()
291 	if ((long)dev->blkdev->bd_inode->i_size % erase_size) {  in add_device()
296 	mutex_init(&dev->write_mutex);  in add_device()
307 	dev->mtd.name = name;  in add_device()
309 	dev->mtd.size = dev->blkdev->bd_inode->i_size & PAGE_MASK;  in add_device()
310 	dev->mtd.erasesize = erase_size;  in add_device()
311 	dev->mtd.writesize = 1;  in add_device()
312 	dev->mtd.writebufsize = PAGE_SIZE;  in add_device()
313 	dev->mtd.type = MTD_RAM;  in add_device()
314 	dev->mtd.flags = MTD_CAP_RAM;  in add_device()
315 	dev->mtd._erase = block2mtd_erase;  in add_device()
316 	dev->mtd._write = block2mtd_write;  in add_device()
317 	dev->mtd._sync = block2mtd_sync;  in add_device()
318 	dev->mtd._read = block2mtd_read;  in add_device()
319 	dev->mtd.priv = dev;  in add_device()
320 	dev->mtd.owner = THIS_MODULE;  in add_device()
322 	if (mtd_device_register(&dev->mtd, NULL, 0)) {  in add_device()
327 	list_add(&dev->list, &blkmtd_device_list);  in add_device()
329 		dev->mtd.index,  in add_device()
330 		label ? label : dev->mtd.name + strlen("block2mtd: "),  in add_device()
331 		dev->mtd.erasesize >> 10, dev->mtd.erasesize);  in add_device()
335 	mutex_destroy(&dev->write_mutex);  in add_device()
343  * allows some suffixes for a more human-readable number format:
344  * ki, Ki, kiB, KiB	- multiply result with 1024
345  * Mi, MiB		- multiply result with 1024^2
346  * Gi, GiB		- multiply result with 1024^3
373 static int parse_num(size_t *num, const char *token)  in parse_num()  argument
378 	n = (size_t) ustrtoul(token, &endp, 0);  in parse_num()
380 		return -EINVAL;  in parse_num()
406 	char *token[BLOCK2MTD_PARAM_MAX_COUNT];  in block2mtd_setup2()  local
422 		token[i] = strsep(&str, ",");  in block2mtd_setup2()
429 	if (!token[0]) {  in block2mtd_setup2()
434 	name = token[0];  in block2mtd_setup2()
441 	if (token[1] && strlen(token[1])) {  in block2mtd_setup2()
442 		ret = parse_num(&erase_size, token[1]);  in block2mtd_setup2()
449 	if (token[2]) {  in block2mtd_setup2()
450 		label = token[2];  in block2mtd_setup2()
511 		block2mtd_sync(&dev->mtd);  in block2mtd_exit()
512 		mtd_device_unregister(&dev->mtd);  in block2mtd_exit()
513 		mutex_destroy(&dev->write_mutex);  in block2mtd_exit()
515 			dev->mtd.index,  in block2mtd_exit()
516 			dev->mtd.name + strlen("block2mtd: "));  in block2mtd_exit()
517 		list_del(&dev->list);  in block2mtd_exit()