1 files changed, 80 insertions, 148 deletions

diff --git a/drivers/mtd/devices/block2mtd.c b/drivers/mtd/devices/block2mtd.c
index 401c6a294ba..66f0405f7e5 100644
--- a/drivers/mtd/devices/block2mtd.c
+++ b/drivers/mtd/devices/block2mtd.c
@@ -1,13 +1,14 @@
 /*
- * $Id: block2mtd.c,v 1.30 2005/11/29 14:48:32 gleixner Exp $
- *
  * block2mtd.c - create an mtd from a block device
  *
  * Copyright (C) 2001,2002	Simon Evans <spse@secret.org.uk>
- * Copyright (C) 2004-2006	Jörn Engel <joern@wh.fh-wedel.de>
+ * Copyright (C) 2004-2006	Joern Engel <joern@wh.fh-wedel.de>
  *
  * Licence: GPL
  */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
 #include <linux/module.h>
 #include <linux/fs.h>
 #include <linux/blkdev.h>
@@ -16,16 +17,10 @@
 #include <linux/list.h>
 #include <linux/init.h>
 #include <linux/mtd/mtd.h>
-#include <linux/buffer_head.h>
 #include <linux/mutex.h>
 #include <linux/mount.h>
-
-#define VERSION "$Revision: 1.30 $"
-
-
-#define ERROR(fmt, args...) printk(KERN_ERR "block2mtd: " fmt "\n" , ## args)
-#define INFO(fmt, args...) printk(KERN_INFO "block2mtd: " fmt "\n" , ## args)
-
+#include <linux/slab.h>
+#include <linux/major.h>
 
 /* Info for the block device */
 struct block2mtd_dev {
@@ -40,60 +35,11 @@ struct block2mtd_dev {
 static LIST_HEAD(blkmtd_device_list);
 
 
-#define PAGE_READAHEAD 64
-static void cache_readahead(struct address_space *mapping, int index)
-{
-	filler_t *filler = (filler_t*)mapping->a_ops->readpage;
-	int i, pagei;
-	unsigned ret = 0;
-	unsigned long end_index;
-	struct page *page;
-	LIST_HEAD(page_pool);
-	struct inode *inode = mapping->host;
-	loff_t isize = i_size_read(inode);
-
-	if (!isize) {
-		INFO("iSize=0 in cache_readahead\n");
-		return;
-	}
-
-	end_index = ((isize - 1) >> PAGE_CACHE_SHIFT);
-
-	read_lock_irq(&mapping->tree_lock);
-	for (i = 0; i < PAGE_READAHEAD; i++) {
-		pagei = index + i;
-		if (pagei > end_index) {
-			INFO("Overrun end of disk in cache readahead\n");
-			break;
-		}
-		page = radix_tree_lookup(&mapping->page_tree, pagei);
-		if (page && (!i))
-			break;
-		if (page)
-			continue;
-		read_unlock_irq(&mapping->tree_lock);
-		page = page_cache_alloc_cold(mapping);
-		read_lock_irq(&mapping->tree_lock);
-		if (!page)
-			break;
-		page->index = pagei;
-		list_add(&page->lru, &page_pool);
-		ret++;
-	}
-	read_unlock_irq(&mapping->tree_lock);
-	if (ret)
-		read_cache_pages(mapping, &page_pool, filler, NULL);
-}
-
-
-static struct page* page_readahead(struct address_space *mapping, int index)
+static struct page *page_read(struct address_space *mapping, int index)
 {
-	filler_t *filler = (filler_t*)mapping->a_ops->readpage;
-	cache_readahead(mapping, index);
-	return read_cache_page(mapping, index, filler, NULL);
+	return read_mapping_page(mapping, index, NULL);
 }
 
-
 /* erase a specified part of the device */
 static int _block2mtd_erase(struct block2mtd_dev *dev, loff_t to, size_t len)
 {
@@ -105,19 +51,18 @@ static int _block2mtd_erase(struct block2mtd_dev *dev, loff_t to, size_t len)
 	u_long *max;
 
 	while (pages) {
-		page = page_readahead(mapping, index);
-		if (!page)
-			return -ENOMEM;
+		page = page_read(mapping, index);
 		if (IS_ERR(page))
 			return PTR_ERR(page);
 
-		max = (u_long*)page_address(page) + PAGE_SIZE;
-		for (p=(u_long*)page_address(page); p<max; p++)
+		max = page_address(page) + PAGE_SIZE;
+		for (p=page_address(page); p<max; p++)
 			if (*p != -1UL) {
 				lock_page(page);
 				memset(page_address(page), 0xff, PAGE_SIZE);
 				set_page_dirty(page);
 				unlock_page(page);
+				balance_dirty_pages_ratelimited(mapping);
 				break;
 			}
 
@@ -139,12 +84,11 @@ static int block2mtd_erase(struct mtd_info *mtd, struct erase_info *instr)
 	err = _block2mtd_erase(dev, from, len);
 	mutex_unlock(&dev->write_mutex);
 	if (err) {
-		ERROR("erase failed err = %d", err);
+		pr_err("erase failed err = %d\n", err);
 		instr->state = MTD_ERASE_FAILED;
 	} else
 		instr->state = MTD_ERASE_DONE;
 
-	instr->state = MTD_ERASE_DONE;
 	mtd_erase_callback(instr);
 	return err;
 }
@@ -159,14 +103,6 @@ static int block2mtd_read(struct mtd_info *mtd, loff_t from, size_t len,
 	int offset = from & (PAGE_SIZE-1);
 	int cpylen;
 
-	if (from > mtd->size)
-		return -EINVAL;
-	if (from + len > mtd->size)
-		len = mtd->size - from;
-
-	if (retlen)
-		*retlen = 0;
-
 	while (len) {
 		if ((offset + len) > PAGE_SIZE)
 			cpylen = PAGE_SIZE - offset;	// multiple pages
@@ -174,10 +110,7 @@ static int block2mtd_read(struct mtd_info *mtd, loff_t from, size_t len,
 			cpylen = len;	// this page
 		len = len - cpylen;
 
-		//      Get page
-		page = page_readahead(dev->blkdev->bd_inode->i_mapping, index);
-		if (!page)
-			return -ENOMEM;
+		page = page_read(dev->blkdev->bd_inode->i_mapping, index);
 		if (IS_ERR(page))
 			return PTR_ERR(page);
 
@@ -204,8 +137,6 @@ static int _block2mtd_write(struct block2mtd_dev *dev, const u_char *buf,
 	int offset = to & ~PAGE_MASK;	// page offset
 	int cpylen;
 
-	if (retlen)
-		*retlen = 0;
 	while (len) {
 		if ((offset+len) > PAGE_SIZE)
 			cpylen = PAGE_SIZE - offset;	// multiple pages
@@ -213,10 +144,7 @@ static int _block2mtd_write(struct block2mtd_dev *dev, const u_char *buf,
 			cpylen = len;			// this page
 		len = len - cpylen;
 
-		//	Get page
-		page = page_readahead(mapping, index);
-		if (!page)
-			return -ENOMEM;
+		page = page_read(mapping, index);
 		if (IS_ERR(page))
 			return PTR_ERR(page);
 
@@ -225,6 +153,7 @@ static int _block2mtd_write(struct block2mtd_dev *dev, const u_char *buf,
 			memcpy(page_address(page) + offset, buf, cpylen);
 			set_page_dirty(page);
 			unlock_page(page);
+			balance_dirty_pages_ratelimited(mapping);
 		}
 		page_cache_release(page);
 
@@ -245,13 +174,6 @@ static int block2mtd_write(struct mtd_info *mtd, loff_t to, size_t len,
 	struct block2mtd_dev *dev = mtd->priv;
 	int err;
 
-	if (!len)
-		return 0;
-	if (to >= mtd->size)
-		return -ENOSPC;
-	if (to + len > mtd->size)
-		len = mtd->size - to;
-
 	mutex_lock(&dev->write_mutex);
 	err = _block2mtd_write(dev, buf, to, len, retlen);
 	mutex_unlock(&dev->write_mutex);
@@ -278,89 +200,96 @@ static void block2mtd_free_device(struct block2mtd_dev *dev)
 	kfree(dev->mtd.name);
 
 	if (dev->blkdev) {
-		invalidate_inode_pages(dev->blkdev->bd_inode->i_mapping);
-		close_bdev_excl(dev->blkdev);
+		invalidate_mapping_pages(dev->blkdev->bd_inode->i_mapping,
+					0, -1);
+		blkdev_put(dev->blkdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
 	}
 
 	kfree(dev);
 }
 
 
-/* FIXME: ensure that mtd->size % erase_size == 0 */
 static struct block2mtd_dev *add_device(char *devname, int erase_size)
 {
+	const fmode_t mode = FMODE_READ | FMODE_WRITE | FMODE_EXCL;
 	struct block_device *bdev;
 	struct block2mtd_dev *dev;
+	char *name;
 
 	if (!devname)
 		return NULL;
 
-	dev = kmalloc(sizeof(struct block2mtd_dev), GFP_KERNEL);
+	dev = kzalloc(sizeof(struct block2mtd_dev), GFP_KERNEL);
 	if (!dev)
 		return NULL;
-	memset(dev, 0, sizeof(*dev));
 
 	/* Get a handle on the device */
-	bdev = open_bdev_excl(devname, O_RDWR, NULL);
+	bdev = blkdev_get_by_path(devname, mode, dev);
 #ifndef MODULE
 	if (IS_ERR(bdev)) {
 
 		/* We might not have rootfs mounted at this point. Try
 		   to resolve the device name by other means. */
 
-		dev_t dev = name_to_dev_t(devname);
-		if (dev != 0) {
-			bdev = open_by_devnum(dev, FMODE_WRITE | FMODE_READ);
-		}
+		dev_t devt = name_to_dev_t(devname);
+		if (devt)
+			bdev = blkdev_get_by_dev(devt, mode, dev);
 	}
 #endif
 
 	if (IS_ERR(bdev)) {
-		ERROR("error: cannot open device %s", devname);
-		goto devinit_err;
+		pr_err("error: cannot open device %s\n", devname);
+		goto err_free_block2mtd;
 	}
 	dev->blkdev = bdev;
 
 	if (MAJOR(bdev->bd_dev) == MTD_BLOCK_MAJOR) {
-		ERROR("attempting to use an MTD device as a block device");
-		goto devinit_err;
+		pr_err("attempting to use an MTD device as a block device\n");
+		goto err_free_block2mtd;
+	}
+
+	if ((long)dev->blkdev->bd_inode->i_size % erase_size) {
+		pr_err("erasesize must be a divisor of device size\n");
+		goto err_free_block2mtd;
 	}
 
 	mutex_init(&dev->write_mutex);
 
 	/* Setup the MTD structure */
 	/* make the name contain the block device in */
-	dev->mtd.name = kmalloc(sizeof("block2mtd: ") + strlen(devname),
-			GFP_KERNEL);
-	if (!dev->mtd.name)
-		goto devinit_err;
+	name = kasprintf(GFP_KERNEL, "block2mtd: %s", devname);
+	if (!name)
+		goto err_destroy_mutex;
 
-	sprintf(dev->mtd.name, "block2mtd: %s", devname);
+	dev->mtd.name = name;
 
 	dev->mtd.size = dev->blkdev->bd_inode->i_size & PAGE_MASK;
 	dev->mtd.erasesize = erase_size;
 	dev->mtd.writesize = 1;
+	dev->mtd.writebufsize = PAGE_SIZE;
 	dev->mtd.type = MTD_RAM;
 	dev->mtd.flags = MTD_CAP_RAM;
-	dev->mtd.erase = block2mtd_erase;
-	dev->mtd.write = block2mtd_write;
-	dev->mtd.writev = default_mtd_writev;
-	dev->mtd.sync = block2mtd_sync;
-	dev->mtd.read = block2mtd_read;
+	dev->mtd._erase = block2mtd_erase;
+	dev->mtd._write = block2mtd_write;
+	dev->mtd._sync = block2mtd_sync;
+	dev->mtd._read = block2mtd_read;
 	dev->mtd.priv = dev;
 	dev->mtd.owner = THIS_MODULE;
 
-	if (add_mtd_device(&dev->mtd)) {
-		/* Device didnt get added, so free the entry */
-		goto devinit_err;
+	if (mtd_device_register(&dev->mtd, NULL, 0)) {
+		/* Device didn't get added, so free the entry */
+		goto err_destroy_mutex;
 	}
 	list_add(&dev->list, &blkmtd_device_list);
-	INFO("mtd%d: [%s] erase_size = %dKiB [%d]", dev->mtd.index,
-			dev->mtd.name + strlen("blkmtd: "),
-			dev->mtd.erasesize >> 10, dev->mtd.erasesize);
+	pr_info("mtd%d: [%s] erase_size = %dKiB [%d]\n",
+		dev->mtd.index,
+		dev->mtd.name + strlen("block2mtd: "),
+		dev->mtd.erasesize >> 10, dev->mtd.erasesize);
 	return dev;
 
-devinit_err:
+err_destroy_mutex:
+	mutex_destroy(&dev->write_mutex);
+err_free_block2mtd:
 	block2mtd_free_device(dev);
 	return NULL;
 }
@@ -417,17 +346,11 @@ static inline void kill_final_newline(char *str)
 }
 
 
-#define parse_err(fmt, args...) do {		\
-	ERROR("block2mtd: " fmt "\n", ## args);	\
-	return 0;				\
-} while (0)
-
 #ifndef MODULE
 static int block2mtd_init_called = 0;
-static __initdata char block2mtd_paramline[80 + 12]; /* 80 for device, 12 for erase size */
+static char block2mtd_paramline[80 + 12]; /* 80 for device, 12 for erase size */
 #endif
 
-
 static int block2mtd_setup2(const char *val)
 {
 	char buf[80 + 12]; /* 80 for device, 12 for erase size */
@@ -437,8 +360,10 @@ static int block2mtd_setup2(const char *val)
 	size_t erase_size = PAGE_SIZE;
 	int i, ret;
 
-	if (strnlen(val, sizeof(buf)) >= sizeof(buf))
-		parse_err("parameter too long");
+	if (strnlen(val, sizeof(buf)) >= sizeof(buf)) {
+		pr_err("parameter too long\n");
+		return 0;
+	}
 
 	strcpy(str, val);
 	kill_final_newline(str);
@@ -446,21 +371,27 @@ static int block2mtd_setup2(const char *val)
 	for (i = 0; i < 2; i++)
 		token[i] = strsep(&str, ",");
 
-	if (str)
-		parse_err("too many arguments");
+	if (str) {
+		pr_err("too many arguments\n");
+		return 0;
+	}
 
-	if (!token[0])
-		parse_err("no argument");
+	if (!token[0]) {
+		pr_err("no argument\n");
+		return 0;
+	}
 
 	name = token[0];
-	if (strlen(name) + 1 > 80)
-		parse_err("device name too long");
+	if (strlen(name) + 1 > 80) {
+		pr_err("device name too long\n");
+		return 0;
+	}
 
 	if (token[1]) {
 		ret = parse_num(&erase_size, token[1]);
 		if (ret) {
-			kfree(name);
-			parse_err("illegal erase size");
+			pr_err("illegal erase size\n");
+			return 0;
 		}
 	}
 
@@ -503,7 +434,6 @@ MODULE_PARM_DESC(block2mtd, "Device to use. \"block2mtd=<dev>[,<erasesize>]\"");
 static int __init block2mtd_init(void)
 {
 	int ret = 0;
-	INFO("version " VERSION);
 
 #ifndef MODULE
 	if (strlen(block2mtd_paramline))
@@ -515,7 +445,7 @@ static int __init block2mtd_init(void)
 }
 
 
-static void __devexit block2mtd_exit(void)
+static void block2mtd_exit(void)
 {
 	struct list_head *pos, *next;
 
@@ -523,9 +453,11 @@ static void __devexit block2mtd_exit(void)
 	list_for_each_safe(pos, next, &blkmtd_device_list) {
 		struct block2mtd_dev *dev = list_entry(pos, typeof(*dev), list);
 		block2mtd_sync(&dev->mtd);
-		del_mtd_device(&dev->mtd);
-		INFO("mtd%d: [%s] removed", dev->mtd.index,
-				dev->mtd.name + strlen("blkmtd: "));
+		mtd_device_unregister(&dev->mtd);
+		mutex_destroy(&dev->write_mutex);
+		pr_info("mtd%d: [%s] removed\n",
+			dev->mtd.index,
+			dev->mtd.name + strlen("block2mtd: "));
 		list_del(&dev->list);
 		block2mtd_free_device(dev);
 	}
@@ -536,5 +468,5 @@ module_init(block2mtd_init);
 module_exit(block2mtd_exit);
 
 MODULE_LICENSE("GPL");
-MODULE_AUTHOR("Simon Evans <spse@secret.org.uk> and others");
+MODULE_AUTHOR("Joern Engel <joern@lazybastard.org>");
 MODULE_DESCRIPTION("Emulate an MTD using a block device");