patch-2.4.21 linux-2.4.21/drivers/mtd/devices/blkmtd.c

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diff -urN linux-2.4.20/drivers/mtd/devices/blkmtd.c linux-2.4.21/drivers/mtd/devices/blkmtd.c
@@ -1,57 +1,36 @@
-/* 
- * $Id: blkmtd.c,v 1.7 2001/11/10 17:06:30 spse Exp $
+/*
+ * $Id: blkmtd.c,v 1.17 2003/01/24 13:00:24 dwmw2 Exp $
  *
  * blkmtd.c - use a block device as a fake MTD
  *
  * Author: Simon Evans <spse@secret.org.uk>
  *
- * Copyright (C) 2001 Simon Evans
- * 
+ * Copyright (C) 2001,2002 Simon Evans
+ *
  * Licence: GPL
  *
  * How it works:
- *       The driver uses raw/io to read/write the device and the page
- *       cache to cache access. Writes update the page cache with the
- *       new data but make a copy of the new page(s) and then a kernel
- *       thread writes pages out to the device in the background. This
- *       ensures that writes are order even if a page is updated twice.
- *       Also, since pages in the page cache are never marked as dirty,
- *       we dont have to worry about writepage() being called on some 
- *       random page which may not be in the write order.
- * 
- *       Erases are handled like writes, so the callback is called after
- *       the page cache has been updated. Sync()ing will wait until it is 
- *       all done.
+ *	The driver uses raw/io to read/write the device and the page
+ *	cache to cache access. Writes update the page cache with the
+ *	new data and mark it dirty and add the page into a kiobuf.
+ *	When the kiobuf becomes full or the next extry is to an earlier
+ *	block in the kiobuf then it is flushed to disk. This allows
+ *	writes to remained ordered and gives a small and simple outgoing
+ *	write cache.
  *
- *       It can be loaded Read-Only to prevent erases and writes to the 
- *       medium.
+ *	It can be loaded Read-Only to prevent erases and writes to the
+ *	medium.
  *
- * Todo:
- *       Make the write queue size dynamic so this it is not too big on
- *       small memory systems and too small on large memory systems.
- * 
- *       Page cache usage may still be a bit wrong. Check we are doing
- *       everything properly.
- * 
- *       Somehow allow writes to dirty the page cache so we dont use too
- *       much memory making copies of outgoing pages. Need to handle case
- *       where page x is written to, then page y, then page x again before
- *       any of them have been committed to disk.
- * 
- *       Reading should read multiple pages at once rather than using 
- *       readpage() for each one. This is easy and will be fixed asap.
  */
 
-
 #include <linux/config.h>
 #include <linux/module.h>
-
 #include <linux/fs.h>
-#include <linux/pagemap.h>
+#include <linux/blkdev.h>
 #include <linux/iobuf.h>
 #include <linux/slab.h>
 #include <linux/pagemap.h>
-#include <linux/mtd/compatmac.h>
+#include <linux/list.h>
 #include <linux/mtd/mtd.h>
 
 #ifdef CONFIG_MTD_DEBUG
@@ -63,918 +42,918 @@
 #endif
 
 
-/* Default erase size in K, always make it a multiple of PAGE_SIZE */
-#define CONFIG_MTD_BLKDEV_ERASESIZE 128
-#define VERSION "1.7"
-extern int *blk_size[];
-extern int *blksize_size[];
+#define err(format, arg...) printk(KERN_ERR "blkmtd: " format "\n" , ## arg)
+#define info(format, arg...) printk(KERN_INFO "blkmtd: " format "\n" , ## arg)
+#define warn(format, arg...) printk(KERN_WARNING "blkmtd: " format "\n" , ## arg)
+#define crit(format, arg...) printk(KERN_CRIT "blkmtd: " format "\n" , ## arg)
 
-/* Info for the block device */
-typedef struct mtd_raw_dev_data_s {
-  struct block_device *binding;
-  int sector_size, sector_bits;
-  int partial_last_page;   // 0 if device ends on page boundary, else page no of last page
-  int last_page_sectors;   // Number of sectors in last page if partial_last_page != 0
-  size_t totalsize;
-  int readonly;
-  struct address_space as;
-  struct mtd_info mtd_info;
-} mtd_raw_dev_data_t;
-
-/* Info for each queue item in the write queue */
-typedef struct mtdblkdev_write_queue_s {
-  mtd_raw_dev_data_t *rawdevice;
-  struct page **pages;
-  int pagenr;
-  int pagecnt;
-  int iserase;
-} mtdblkdev_write_queue_t;
 
+/* Default erase size in KiB, always make it a multiple of PAGE_SIZE */
+#define CONFIG_MTD_BLKDEV_ERASESIZE (128 << 10)	/* 128KiB */
+#define VERSION "1.10"
+
+/* Info for the block device */
+struct blkmtd_dev {
+	struct list_head list;
+	struct block_device *binding;
+	struct mtd_info mtd_info;
+	struct kiobuf *rd_buf, *wr_buf;
+	long iobuf_locks;
+	struct semaphore wrbuf_mutex;
+};
 
-/* Our erase page - always remains locked. */
-static struct page *erase_page;
 
 /* Static info about the MTD, used in cleanup_module */
-static mtd_raw_dev_data_t *mtd_rawdevice;
+static LIST_HEAD(blkmtd_device_list);
 
-/* Write queue fixed size */
-#define WRITE_QUEUE_SZ 512
 
-/* Storage for the write queue */
-static mtdblkdev_write_queue_t *write_queue;
-static int write_queue_sz = WRITE_QUEUE_SZ;
-static int volatile write_queue_head;
-static int volatile write_queue_tail;
-static int volatile write_queue_cnt;
-static spinlock_t mbd_writeq_lock = SPIN_LOCK_UNLOCKED;
-
-/* Tell the write thread to finish */
-static volatile int write_task_finish;
-
-/* ipc with the write thread */
-#if LINUX_VERSION_CODE > KERNEL_VERSION(2,3,0)
-static DECLARE_MUTEX_LOCKED(thread_sem);
-static DECLARE_WAIT_QUEUE_HEAD(thr_wq);
-static DECLARE_WAIT_QUEUE_HEAD(mtbd_sync_wq);
-#else
-static struct semaphore thread_sem = MUTEX_LOCKED;
-DECLARE_WAIT_QUEUE_HEAD(thr_wq);
-DECLARE_WAIT_QUEUE_HEAD(mtbd_sync_wq);
-#endif
+static void blkmtd_sync(struct mtd_info *mtd);
 
+#define MAX_DEVICES 4
 
 /* Module parameters passed by insmod/modprobe */
-char *device;    /* the block device to use */
-int erasesz;     /* optional default erase size */
-int ro;          /* optional read only flag */
-int bs;          /* optionally force the block size (avoid using) */
-int count;       /* optionally force the block count (avoid using) */
-int wqs;         /* optionally set the write queue size */
+char *device[MAX_DEVICES];    /* the block device to use */
+int erasesz[MAX_DEVICES];     /* optional default erase size */
+int ro[MAX_DEVICES];          /* optional read only flag */
+int sync;
 
 
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,2,0)
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Simon Evans <spse@secret.org.uk>");
 MODULE_DESCRIPTION("Emulate an MTD using a block device");
-MODULE_PARM(device, "s");
+MODULE_PARM(device, "1-4s");
 MODULE_PARM_DESC(device, "block device to use");
-MODULE_PARM(erasesz, "i");
-MODULE_PARM_DESC(erasesz, "optional erase size to use in KB. eg 4=4K.");
-MODULE_PARM(ro, "i");
+MODULE_PARM(erasesz, "1-4i");
+MODULE_PARM_DESC(erasesz, "optional erase size to use in KiB. eg 4=4KiB.");
+MODULE_PARM(ro, "1-4i");
 MODULE_PARM_DESC(ro, "1=Read only, writes and erases cause errors");
-MODULE_PARM(bs, "i");
-MODULE_PARM_DESC(bs, "force the block size in bytes");
-MODULE_PARM(count, "i");
-MODULE_PARM_DESC(count, "force the block count");
-MODULE_PARM(wqs, "i");
-#endif
-
+MODULE_PARM(sync, "i");
+MODULE_PARM_DESC(sync, "1=Synchronous writes");
 
-/* Page cache stuff */
 
-/* writepage() - should never be called - catch it anyway */
-static int blkmtd_writepage(struct page *page)
+/**
+ * read_pages - read in pages via the page cache
+ * @dev: device to read from
+ * @pagenrs: list of page numbers wanted
+ * @pagelst: storage for struce page * pointers
+ * @pages: count of pages wanted
+ *
+ * Read pages, getting them from the page cache if available
+ * else reading them in from disk if not. pagelst must be preallocated
+ * to hold the page count.
+ */
+static int read_pages(struct blkmtd_dev *dev, int pagenrs[], struct page **pagelst, int pages)
 {
-  printk("blkmtd: writepage called!!!\n");
-  return -EIO;
-}
-
-
-/* readpage() - reads one page from the block device */                 
-static int blkmtd_readpage(mtd_raw_dev_data_t *rawdevice, struct page *page)
-{  
-  int err;
-  int sectornr, sectors, i;
-  struct kiobuf *iobuf;
-  kdev_t dev;
-  unsigned long *blocks;
-
-  if(!rawdevice) {
-    printk("blkmtd: readpage: PANIC file->private_data == NULL\n");
-    return -EIO;
-  }
-  dev = to_kdev_t(rawdevice->binding->bd_dev);
-
-  DEBUG(2, "blkmtd: readpage called, dev = `%s' page = %p index = %ld\n",
-	bdevname(dev), page, page->index);
-
-  if(Page_Uptodate(page)) {
-    DEBUG(2, "blkmtd: readpage page %ld is already upto date\n", page->index);
-    UnlockPage(page);
-    return 0;
-  }
-
-  ClearPageUptodate(page);
-  ClearPageError(page);
-
-  /* see if page is in the outgoing write queue */
-  spin_lock(&mbd_writeq_lock);
-  if(write_queue_cnt) {
-    int i = write_queue_tail;
-    while(i != write_queue_head) {
-      mtdblkdev_write_queue_t *item = &write_queue[i];
-      if(page->index >= item->pagenr && page->index < item->pagenr+item->pagecnt) {
-	/* yes it is */
-	int index = page->index - item->pagenr;
-		
-	DEBUG(2, "blkmtd: readpage: found page %ld in outgoing write queue\n",
-	      page->index);
-	if(item->iserase) {
-	  memset(page_address(page), 0xff, PAGE_SIZE);
-	} else {
-	  memcpy(page_address(page), page_address(item->pages[index]), PAGE_SIZE);
+	kdev_t kdev;
+	struct page *page;
+	int cnt = 0;
+	struct kiobuf *iobuf;
+	int err = 0;
+
+	if(!dev) {
+		err("read_pages: PANIC dev == NULL");
+		return -EIO;
 	}
-	SetPageUptodate(page);
-	flush_dcache_page(page);
-	UnlockPage(page);
-	spin_unlock(&mbd_writeq_lock);
-	return 0;
-      }
-      i++;
-      i %= write_queue_sz;
-    }
-  }
-  spin_unlock(&mbd_writeq_lock);
-
-
-  DEBUG(3, "blkmtd: readpage: getting kiovec\n");
-  err = alloc_kiovec(1, &iobuf);
-  if (err) {
-    printk("blkmtd: cant allocate kiobuf\n");
-    SetPageError(page);
-    return err;
-  }
+	kdev = to_kdev_t(dev->binding->bd_dev);
 
-  /* Pre 2.4.4 doesn't have space for the block list in the kiobuf */ 
+	DEBUG(2, "read_pages: reading %d pages\n", pages);
+	if(test_and_set_bit(0, &dev->iobuf_locks)) {
+		err = alloc_kiovec(1, &iobuf);
+		if (err) {
+			crit("cant allocate kiobuf");
+			return -ENOMEM;
+		}
 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,4,4)
-  blocks = kmalloc(KIO_MAX_SECTORS * sizeof(unsigned long));
-  if(blocks == NULL) {
-    printk("blkmtd: cant allocate iobuf blocks\n");
-    free_kiovec(1, &iobuf);
-    SetPageError(page);
-    return -ENOMEM;
-  }
-#else 
-  blocks = iobuf->blocks;
+		iobuf->blocks = kmalloc(KIO_MAX_SECTORS * sizeof(unsigned long), GFP_KERNEL);
+		if(iobuf->blocks == NULL) {
+			crit("cant allocate iobuf blocks");
+			free_kiovec(1, &iobuf);
+			return -ENOMEM;
+		}
 #endif
+	} else {
+		iobuf = dev->rd_buf;
+	}
+
+	iobuf->nr_pages = 0;
+	iobuf->length = 0;
+	iobuf->offset = 0;
+	iobuf->locked = 1;
+	
+	for(cnt = 0; cnt < pages; cnt++) {
+		page = grab_cache_page(dev->binding->bd_inode->i_mapping, pagenrs[cnt]);
+		pagelst[cnt] = page;
+		if(!PageUptodate(page)) {
+				iobuf->blocks[iobuf->nr_pages] = pagenrs[cnt];
+				iobuf->maplist[iobuf->nr_pages++] = page;
+		}
+	}
+
+	if(iobuf->nr_pages) {
+		iobuf->length = iobuf->nr_pages << PAGE_SHIFT;
+		err = brw_kiovec(READ, 1, &iobuf, kdev, iobuf->blocks, PAGE_SIZE);
+		DEBUG(3, "blkmtd: read_pages: finished, err = %d\n", err);
+		if(err < 0) {
+			while(pages--) {
+				ClearPageUptodate(pagelst[pages]);
+				unlock_page(pagelst[pages]);
+				page_cache_release(pagelst[pages]);
+			}
+		} else {
+			while(iobuf->nr_pages--) {
+				SetPageUptodate(iobuf->maplist[iobuf->nr_pages]);
+			}
+			err = 0;
+		}
+	}
 
-  iobuf->offset = 0;
-  iobuf->nr_pages = 1;
-  iobuf->length = PAGE_SIZE;
-  iobuf->locked = 1;
-  iobuf->maplist[0] = page;
-  sectornr = page->index << (PAGE_SHIFT - rawdevice->sector_bits);
-  sectors = 1 << (PAGE_SHIFT - rawdevice->sector_bits);
-  if(rawdevice->partial_last_page && page->index == rawdevice->partial_last_page) {
-    DEBUG(3, "blkmtd: handling partial last page\n");
-    sectors = rawdevice->last_page_sectors;
-  }
-  DEBUG(3, "blkmtd: readpage: sectornr = %d sectors = %d\n", sectornr, sectors);
-  for(i = 0; i < sectors; i++) {
-    blocks[i] = sectornr++;
-  }
-  /* If only a partial page read in, clear the rest of the page */
-  if(rawdevice->partial_last_page && page->index == rawdevice->partial_last_page) {
-    int offset = rawdevice->last_page_sectors << rawdevice->sector_bits;
-    int count = PAGE_SIZE-offset;
-    DEBUG(3, "blkmtd: clear last partial page: offset = %d count = %d\n", offset, count);
-    memset(page_address(page)+offset, 0, count);
-    sectors = rawdevice->last_page_sectors;
-  }
-
-
-  DEBUG(3, "bklmtd: readpage: starting brw_kiovec\n");
-  err = brw_kiovec(READ, 1, &iobuf, dev, blocks, rawdevice->sector_size);
-  DEBUG(3, "blkmtd: readpage: finished, err = %d\n", err);
-  iobuf->locked = 0;
-  free_kiovec(1, &iobuf);
 
+	if(iobuf != dev->rd_buf) {
 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,4,4)
-  kfree(blocks);
+		kfree(iobuf->blocks);
 #endif
-
-  if(err != PAGE_SIZE) {
-    printk("blkmtd: readpage: error reading page %ld\n", page->index);
-    memset(page_address(page), 0, PAGE_SIZE);
-    SetPageError(page);
-    err = -EIO;
-  } else {
-    DEBUG(3, "blkmtd: readpage: setting page upto date\n");
-    SetPageUptodate(page);
-    err = 0;
-  }
-  flush_dcache_page(page);
-  UnlockPage(page);
-  DEBUG(2, "blkmtd: readpage: finished, err = %d\n", err);
-  return 0;
+		free_kiovec(1, &iobuf);
+	} else {
+		clear_bit(0, &dev->iobuf_locks);
+	}
+	DEBUG(2, "read_pages: done, err = %d\n", err);
+	return err;
 }
 
-                    
-static struct address_space_operations blkmtd_aops = {
-  writepage:     blkmtd_writepage,
-  readpage:      NULL,
-}; 
+
+/**
+ * commit_pages - commit pages in the writeout kiobuf to disk
+ * @dev: device to write to
+ *
+ * If the current dev has pages in the dev->wr_buf kiobuf,
+ * they are written to disk using brw_kiovec()
+ */
+static int commit_pages(struct blkmtd_dev *dev)
+{
+	struct kiobuf *iobuf = dev->wr_buf;
+	kdev_t kdev = to_kdev_t(dev->binding->bd_dev);
+	int err = 0;
+
+	iobuf->length = iobuf->nr_pages << PAGE_SHIFT;
+	iobuf->locked = 1;
+	if(iobuf->length) {
+		int i;
+		DEBUG(2, "blkmtd: commit_pages: nrpages = %d\n", iobuf->nr_pages);
+		/* Check all the pages are dirty and lock them */
+		for(i = 0; i < iobuf->nr_pages; i++) {
+			struct page *page = iobuf->maplist[i];
+			BUG_ON(!PageDirty(page));
+			lock_page(page);
+		}
+		err = brw_kiovec(WRITE, 1, &iobuf, kdev, iobuf->blocks, PAGE_SIZE);
+		DEBUG(3, "commit_write: committed %d pages err = %d\n", iobuf->nr_pages, err);
+		while(iobuf->nr_pages) {
+			struct page *page = iobuf->maplist[--iobuf->nr_pages];
+			ClearPageDirty(page);
+			SetPageUptodate(page);
+			unlock_page(page);
+			page_cache_release(page);
+		}
+	}
+
+	DEBUG(2, "blkmtd: sync: end, err = %d\n", err);
+	iobuf->offset = 0;
+	iobuf->nr_pages = 0;
+	iobuf->length = 0;
+	return err;
+}
 
 
-/* This is the kernel thread that empties the write queue to disk */
-static int write_queue_task(void *data)
+/**
+ * write_pages - write block of data to device via the page cache
+ * @dev: device to write to
+ * @buf: data source or NULL if erase (output is set to 0xff)
+ * @to: offset into output device
+ * @len: amount to data to write
+ * @retlen: amount of data written
+ *
+ * Grab pages from the page cache and fill them with the source data.
+ * Non page aligned start and end result in a readin of the page and
+ * part of the page being modified. Pages are added to the wr_buf kiobuf
+ * until this becomes full or the next page written to has a lower pagenr
+ * then the current max pagenr in the kiobuf.
+ */
+static int write_pages(struct blkmtd_dev *dev, const u_char *buf, loff_t to,
+		    size_t len, int *retlen)
 {
-  int err;
-  struct task_struct *tsk = current;
-  struct kiobuf *iobuf;
-  unsigned long *blocks;
-
-  DECLARE_WAITQUEUE(wait, tsk);
-  DEBUG(1, "blkmtd: writetask: starting (pid = %d)\n", tsk->pid);
-  daemonize();
-  strcpy(tsk->comm, "blkmtdd");
-  tsk->tty = NULL;
-  spin_lock_irq(&tsk->sigmask_lock);
-  sigfillset(&tsk->blocked);
-  recalc_sigpending(tsk);
-  spin_unlock_irq(&tsk->sigmask_lock);
-  exit_sighand(tsk);
-
-  if(alloc_kiovec(1, &iobuf)) {
-    printk("blkmtd: write_queue_task cant allocate kiobuf\n");
-    return 0;
-  }
+	int pagenr, offset;
+	size_t start_len = 0, end_len;
+	int pagecnt = 0;
+	struct kiobuf *iobuf = dev->wr_buf;
+	int err = 0;
+	struct page *pagelst[2];
+	int pagenrs[2];
+	int readpages = 0;
+	int ignorepage = -1;
+
+	pagenr = to >> PAGE_SHIFT;
+	offset = to & ~PAGE_MASK;
+
+	DEBUG(2, "blkmtd: write_pages: buf = %p to = %ld len = %d pagenr = %d offset = %d\n",
+	      buf, (long)to, len, pagenr, offset);
+
+	*retlen = 0;
+	/* see if we have to do a partial write at the start */
+	if(offset) {
+		start_len = ((offset + len) > PAGE_SIZE) ? PAGE_SIZE - offset : len;
+		len -= start_len;
+	}
 
-  /* Pre 2.4.4 doesn't have space for the block list in the kiobuf */ 
-#if LINUX_VERSION_CODE < KERNEL_VERSION(2,4,4)
-  blocks = kmalloc(KIO_MAX_SECTORS * sizeof(unsigned long));
-  if(blocks == NULL) {
-    printk("blkmtd: write_queue_task cant allocate iobuf blocks\n");
-    free_kiovec(1, &iobuf);
-    return 0;
-  }
-#else 
-  blocks = iobuf->blocks;
-#endif
+	/* calculate the length of the other two regions */
+	end_len = len & ~PAGE_MASK;
+	len -= end_len;
+
+	if(start_len) {
+		pagenrs[0] = pagenr;
+		readpages++;
+		pagecnt++;
+	}
+	if(len)
+		pagecnt += len >> PAGE_SHIFT;
+	if(end_len) {
+		pagenrs[readpages] = pagenr + pagecnt;
+		readpages++;
+		pagecnt++;
+	}
 
-  DEBUG(2, "blkmtd: writetask: entering main loop\n");
-  add_wait_queue(&thr_wq, &wait);
+	DEBUG(3, "blkmtd: write: start_len = %d len = %d end_len = %d pagecnt = %d\n",
+	      start_len, len, end_len, pagecnt);
 
-  while(1) {
-    spin_lock(&mbd_writeq_lock);
+	down(&dev->wrbuf_mutex);
 
-    if(!write_queue_cnt) {
-      /* If nothing in the queue, wake up anyone wanting to know when there
-	 is space in the queue then sleep for 2*HZ */
-      spin_unlock(&mbd_writeq_lock);
-      DEBUG(4, "blkmtd: writetask: queue empty\n");
-      if(waitqueue_active(&mtbd_sync_wq))
-	 wake_up(&mtbd_sync_wq);
-      interruptible_sleep_on_timeout(&thr_wq, 2*HZ);
-      DEBUG(4, "blkmtd: writetask: woken up\n");
-      if(write_task_finish)
-	break;
-    } else {
-      /* we have stuff to write */
-      mtdblkdev_write_queue_t *item = &write_queue[write_queue_tail];
-      struct page **pages = item->pages;
-
-      int i;
-      int sectornr = item->pagenr << (PAGE_SHIFT - item->rawdevice->sector_bits);
-      int sectorcnt = item->pagecnt << (PAGE_SHIFT - item->rawdevice->sector_bits);
-      int max_sectors = KIO_MAX_SECTORS >> (item->rawdevice->sector_bits - 9);
-      kdev_t dev = to_kdev_t(item->rawdevice->binding->bd_dev);
-
-      /* If we are writing to the last page on the device and it doesn't end
-       * on a page boundary, subtract the number of sectors that dont exist.
-       */
-      if(item->rawdevice->partial_last_page && 
-	 (item->pagenr + item->pagecnt -1) == item->rawdevice->partial_last_page) {
-	sectorcnt -= (1 << (PAGE_SHIFT - item->rawdevice->sector_bits));
-	sectorcnt += item->rawdevice->last_page_sectors;
-      }
-
-      DEBUG(3, "blkmtd: writetask: got %d queue items\n", write_queue_cnt);
-      set_current_state(TASK_RUNNING);
-      spin_unlock(&mbd_writeq_lock);
-
-      DEBUG(2, "blkmtd: writetask: writing pagenr = %d pagecnt = %d sectornr = %d sectorcnt = %d\n", 
-	    item->pagenr, item->pagecnt, sectornr, sectorcnt);
-
-      iobuf->offset = 0;
-      iobuf->locked = 1;
-
-      /* Loop through all the pages to be written in the queue item, remembering
-	 we can only write KIO_MAX_SECTORS at a time */
-	 
-      while(sectorcnt) {
-	int cursectors = (sectorcnt < max_sectors) ? sectorcnt : max_sectors;
-	int cpagecnt = (cursectors << item->rawdevice->sector_bits) + PAGE_SIZE-1;
-	cpagecnt >>= PAGE_SHIFT;
-	
-	for(i = 0; i < cpagecnt; i++) {
-	  if(item->iserase) {
-	    iobuf->maplist[i] = erase_page;
-	  } else {
-	    iobuf->maplist[i] = *(pages++);
-	  }
+	if(iobuf->nr_pages && ((pagenr <= iobuf->blocks[iobuf->nr_pages-1])
+			       || (iobuf->nr_pages + pagecnt) >= KIO_STATIC_PAGES)) {
+
+		if((pagenr == iobuf->blocks[iobuf->nr_pages-1])
+		   && ((iobuf->nr_pages + pagecnt) < KIO_STATIC_PAGES)) {
+			iobuf->nr_pages--;
+			ignorepage = pagenr;
+		} else {
+			DEBUG(3, "blkmtd: doing writeout pagenr = %d max_pagenr = %ld pagecnt = %d idx = %d\n",
+			      pagenr, iobuf->blocks[iobuf->nr_pages-1],
+			      pagecnt, iobuf->nr_pages);
+			commit_pages(dev);
+		}
 	}
 	
-	for(i = 0; i < cursectors; i++) {
-	  blocks[i] = sectornr++;
+	if(readpages) {
+		err = read_pages(dev, pagenrs, pagelst, readpages);
+		if(err < 0)
+			goto readin_err;
 	}
-	
-	iobuf->nr_pages = cpagecnt;
-	iobuf->length = cursectors << item->rawdevice->sector_bits;
-	DEBUG(3, "blkmtd: write_task: about to kiovec\n");
-	err = brw_kiovec(WRITE, 1, &iobuf, dev, blocks, item->rawdevice->sector_size);
-	DEBUG(3, "bklmtd: write_task: done, err = %d\n", err);
-	if(err != (cursectors << item->rawdevice->sector_bits)) {
-	  /* if an error occured - set this to exit the loop */
-	  sectorcnt = 0;
-	} else {
-	  sectorcnt -= cursectors;
+
+	if(start_len) {
+		/* do partial start region */
+		struct page *page;
+
+		DEBUG(3, "blkmtd: write: doing partial start, page = %d len = %d offset = %d\n",
+		      pagenr, start_len, offset);
+		page = pagelst[0];
+		BUG_ON(!buf);
+		if(PageDirty(page) && pagenr != ignorepage) {
+			err("to = %lld start_len = %d len = %d end_len = %d pagenr = %d ignorepage = %d\n",
+			    to, start_len, len, end_len, pagenr, ignorepage);
+			BUG();
+		}
+		memcpy(page_address(page)+offset, buf, start_len);
+		SetPageDirty(page);
+		SetPageUptodate(page);
+		unlock_page(page);
+		buf += start_len;
+		*retlen = start_len;
+		err = 0;
+		iobuf->blocks[iobuf->nr_pages] = pagenr++;
+		iobuf->maplist[iobuf->nr_pages] = page;
+		iobuf->nr_pages++;
 	}
-      }
 
-      /* free up the pages used in the write and list of pages used in the write
-	 queue item */
-      iobuf->locked = 0;
-      spin_lock(&mbd_writeq_lock);
-      write_queue_cnt--;
-      write_queue_tail++;
-      write_queue_tail %= write_queue_sz;
-      if(!item->iserase) {
-	for(i = 0 ; i < item->pagecnt; i++) {
-	  UnlockPage(item->pages[i]);
-	  __free_pages(item->pages[i], 0);
-	}
-	kfree(item->pages);
-      }
-      item->pages = NULL;
-      spin_unlock(&mbd_writeq_lock);
-      /* Tell others there is some space in the write queue */
-      if(waitqueue_active(&mtbd_sync_wq))
-	wake_up(&mtbd_sync_wq);
-    }
-  }
-  remove_wait_queue(&thr_wq, &wait);
-  DEBUG(1, "blkmtd: writetask: exiting\n");
-  free_kiovec(1, &iobuf);
+	/* Now do the main loop to a page aligned, n page sized output */
+	if(len) {
+		int pagesc = len >> PAGE_SHIFT;
+		DEBUG(3, "blkmtd: write: whole pages start = %d, count = %d\n",
+		      pagenr, pagesc);
+		while(pagesc) {
+			struct page *page;
+
+			/* see if page is in the page cache */
+			DEBUG(3, "blkmtd: write: grabbing page %d from page cache\n", pagenr);
+			page = grab_cache_page(dev->binding->bd_inode->i_mapping, pagenr);
+			if(PageDirty(page) && pagenr != ignorepage) {
+				BUG();
+			}
+			if(!page) {
+				warn("write: cant grab cache page %d", pagenr);
+				err = -ENOMEM;
+				goto write_err;
+			}
+			if(!buf) {
+				memset(page_address(page), 0xff, PAGE_SIZE);
+			} else {
+				memcpy(page_address(page), buf, PAGE_SIZE);
+				buf += PAGE_SIZE;
+			}
+			iobuf->blocks[iobuf->nr_pages] = pagenr++;
+			iobuf->maplist[iobuf->nr_pages] = page;
+			iobuf->nr_pages++;
+			SetPageDirty(page);
+			SetPageUptodate(page);
+			unlock_page(page);
+			pagesc--;
+			*retlen += PAGE_SIZE;
+		}
+	}
 
-#if LINUX_VERSION_CODE < KERNEL_VERSION(2,4,4)
-  kfree(blocks);
-#endif
+	if(end_len) {
+		/* do the third region */
+		struct page *page;
+		DEBUG(3, "blkmtd: write: doing partial end, page = %d len = %d\n",
+		      pagenr, end_len);
+		page = pagelst[readpages-1];
+		BUG_ON(!buf);
+		if(PageDirty(page) && pagenr != ignorepage) {
+			err("to = %lld start_len = %d len = %d end_len = %d pagenr = %d ignorepage = %d\n",
+			    to, start_len, len, end_len, pagenr, ignorepage);
+			BUG();
+		}
+		memcpy(page_address(page), buf, end_len);
+		SetPageDirty(page);
+		SetPageUptodate(page);
+		unlock_page(page);
+		DEBUG(3, "blkmtd: write: writing out partial end\n");
+		*retlen += end_len;
+		err = 0;
+		iobuf->blocks[iobuf->nr_pages] = pagenr;
+		iobuf->maplist[iobuf->nr_pages] = page;
+		iobuf->nr_pages++;
+	}
 
-  /* Tell people we have exitd */
-  up(&thread_sem);
-  return 0;
-}
+	DEBUG(2, "blkmtd: write: end, retlen = %d, err = %d\n", *retlen, err);
 
+	if(sync) {
+write_err:
+		commit_pages(dev);
+	}
 
-/* Add a range of pages into the outgoing write queue, making copies of them */
-static int queue_page_write(mtd_raw_dev_data_t *rawdevice, struct page **pages,
-			    int pagenr, int pagecnt, int iserase)
-{
-  struct page *outpage;
-  struct page **new_pages = NULL;
-  mtdblkdev_write_queue_t *item;
-  int i;
-  DECLARE_WAITQUEUE(wait, current);
-  DEBUG(2, "blkmtd: queue_page_write: adding pagenr = %d pagecnt = %d\n", pagenr, pagecnt);
-
-  if(!pagecnt)
-    return 0;
-
-  if(pages == NULL && !iserase)
-    return -EINVAL;
-
-  /* create a array for the list of pages */
-  if(!iserase) {
-    new_pages = kmalloc(pagecnt * sizeof(struct page *), GFP_KERNEL);
-    if(new_pages == NULL)
-      return -ENOMEM;
-
-    /* make copies of the pages in the page cache */
-    for(i = 0; i < pagecnt; i++) {
-      outpage = alloc_pages(GFP_KERNEL, 0);
-      if(!outpage) {
-	while(i--) {
-	  UnlockPage(new_pages[i]);
-	  __free_pages(new_pages[i], 0);
-	}
-	kfree(new_pages);
-	return -ENOMEM;
-      }
-      lock_page(outpage);
-      memcpy(page_address(outpage), page_address(pages[i]), PAGE_SIZE);
-      new_pages[i] = outpage;
-    }
-  }
-
-  /* wait until there is some space in the write queue */
- test_lock:
-  spin_lock(&mbd_writeq_lock);
-  if(write_queue_cnt == write_queue_sz) {
-    spin_unlock(&mbd_writeq_lock);
-    DEBUG(3, "blkmtd: queue_page: Queue full\n");
-    current->state = TASK_UNINTERRUPTIBLE;
-    add_wait_queue(&mtbd_sync_wq, &wait);
-    wake_up_interruptible(&thr_wq);
-    schedule();
-    current->state = TASK_RUNNING;
-    remove_wait_queue(&mtbd_sync_wq, &wait);
-    DEBUG(3, "blkmtd: queue_page_write: Queue has %d items in it\n", write_queue_cnt);
-    goto test_lock;
-  }
-
-  DEBUG(3, "blkmtd: queue_page_write: qhead: %d qtail: %d qcnt: %d\n", 
-	write_queue_head, write_queue_tail, write_queue_cnt);
-
-  /* fix up the queue item */
-  item = &write_queue[write_queue_head];
-  item->pages = new_pages;
-  item->pagenr = pagenr;
-  item->pagecnt = pagecnt;
-  item->rawdevice = rawdevice;
-  item->iserase = iserase;
-
-  write_queue_head++;
-  write_queue_head %= write_queue_sz;
-  write_queue_cnt++;
-  DEBUG(3, "blkmtd: queue_page_write: qhead: %d qtail: %d qcnt: %d\n", 
-	write_queue_head, write_queue_tail, write_queue_cnt);
-  spin_unlock(&mbd_writeq_lock);
-  DEBUG(2, "blkmtd: queue_page_write: finished\n");
-  return 0;
+readin_err:
+	up(&dev->wrbuf_mutex);
+	return err;
 }
 
 
 /* erase a specified part of the device */
 static int blkmtd_erase(struct mtd_info *mtd, struct erase_info *instr)
 {
-  mtd_raw_dev_data_t *rawdevice = mtd->priv;
-  struct mtd_erase_region_info *einfo = mtd->eraseregions;
-  int numregions = mtd->numeraseregions;
-  size_t from;
-  u_long len;
-  int err = 0;
-
-  /* check readonly */
-  if(rawdevice->readonly) {
-    printk("blkmtd: error: trying to erase readonly device %s\n", device);
-    instr->state = MTD_ERASE_FAILED;
-    goto erase_callback;
-  }
-
-  instr->state = MTD_ERASING;
-  from = instr->addr;
-  len = instr->len;
-
-  /* check erase region has valid start and length */
-  DEBUG(2, "blkmtd: erase: dev = `%s' from = 0x%x len = 0x%lx\n",
-	bdevname(rawdevice->binding->bd_dev), from, len);
-  while(numregions) {
-    DEBUG(3, "blkmtd: checking erase region = 0x%08X size = 0x%X num = 0x%x\n",
-	  einfo->offset, einfo->erasesize, einfo->numblocks);
-    if(from >= einfo->offset && from < einfo->offset + (einfo->erasesize * einfo->numblocks)) {
-      if(len == einfo->erasesize && ( (from - einfo->offset) % einfo->erasesize == 0))
-	break;
-    }
-    numregions--;
-    einfo++;
-  }
-
-  if(!numregions) {
-    /* Not a valid erase block */
-    printk("blkmtd: erase: invalid erase request 0x%lX @ 0x%08X\n", len, from);
-    instr->state = MTD_ERASE_FAILED;
-    err = -EIO;
-  }
-  
-  if(instr->state != MTD_ERASE_FAILED) {
-    /* start the erase */
-    int pagenr, pagecnt;
-    struct page *page, **pages;
-    int i = 0;
-
-    /* Handle the last page of the device not being whole */
-    if(len < PAGE_SIZE)
-      len = PAGE_SIZE;
-
-    pagenr = from >> PAGE_SHIFT;
-    pagecnt = len >> PAGE_SHIFT;
-    DEBUG(3, "blkmtd: erase: pagenr = %d pagecnt = %d\n", pagenr, pagecnt);
-
-    pages = kmalloc(pagecnt * sizeof(struct page *), GFP_KERNEL);
-    if(pages == NULL) {
-      err = -ENOMEM;
-      instr->state = MTD_ERASE_FAILED;
-      goto erase_out;
-    }
-
-
-    while(pagecnt) {
-      /* get the page via the page cache */
-      DEBUG(3, "blkmtd: erase: doing grab_cache_page() for page %d\n", pagenr);
-      page = grab_cache_page(&rawdevice->as, pagenr);
-      if(!page) {
-	DEBUG(3, "blkmtd: erase: grab_cache_page() failed for page %d\n", pagenr);
-	kfree(pages);
-	err = -EIO;
-	instr->state = MTD_ERASE_FAILED;
-	goto erase_out;
-      }
-      memset(page_address(page), 0xff, PAGE_SIZE);
-      pages[i] = page;
-      pagecnt--;
-      pagenr++;
-      i++;
-    }
-    DEBUG(3, "blkmtd: erase: queuing page write\n");
-    err = queue_page_write(rawdevice, NULL, from >> PAGE_SHIFT, len >> PAGE_SHIFT, 1);
-    pagecnt = len >> PAGE_SHIFT;
-    if(!err) {
-      while(pagecnt--) {
-	SetPageUptodate(pages[pagecnt]);
-	UnlockPage(pages[pagecnt]);
-	page_cache_release(pages[pagecnt]);
-	flush_dcache_page(pages[pagecnt]);
-      }
-      kfree(pages);
-      instr->state = MTD_ERASE_DONE;
-    } else {
-      while(pagecnt--) {
-	SetPageError(pages[pagecnt]);
-	page_cache_release(pages[pagecnt]);
-      }
-      kfree(pages);
-      instr->state = MTD_ERASE_FAILED;
-    }
-  }
- erase_out:
-  DEBUG(3, "blkmtd: erase: checking callback\n");
+	struct blkmtd_dev *dev = mtd->priv;
+	struct mtd_erase_region_info *einfo = mtd->eraseregions;
+	int numregions = mtd->numeraseregions;
+	size_t from;
+	u_long len;
+	int err = -EIO;
+	int retlen;
+
+	/* check readonly */
+	if(!dev->wr_buf) {
+		err("error: mtd%d trying to erase readonly device %s",
+		    mtd->index, mtd->name);
+		instr->state = MTD_ERASE_FAILED;
+		goto erase_callback;
+	}
+
+	instr->state = MTD_ERASING;
+	from = instr->addr;
+	len = instr->len;
+
+	/* check erase region has valid start and length */
+	DEBUG(2, "blkmtd: erase: dev = `%s' from = 0x%x len = 0x%lx\n",
+	      bdevname(dev->binding->bd_dev), from, len);
+	while(numregions) {
+		DEBUG(3, "blkmtd: checking erase region = 0x%08X size = 0x%X num = 0x%x\n",
+		      einfo->offset, einfo->erasesize, einfo->numblocks);
+		if(from >= einfo->offset
+		   && from < einfo->offset + (einfo->erasesize * einfo->numblocks)) {
+			if(len == einfo->erasesize
+			   && ( (from - einfo->offset) % einfo->erasesize == 0))
+				break;
+		}
+		numregions--;
+		einfo++;
+	}
+
+	if(!numregions) {
+		/* Not a valid erase block */
+		err("erase: invalid erase request 0x%lX @ 0x%08X", len, from);
+		instr->state = MTD_ERASE_FAILED;
+		err = -EIO;
+	}
+
+	if(instr->state != MTD_ERASE_FAILED) {
+		/* do the erase */
+		DEBUG(3, "Doing erase from = %d len = %ld\n", from, len);
+		err = write_pages(dev, NULL, from, len, &retlen);
+		if(err < 0) {
+			err("erase failed err = %d", err);
+			instr->state = MTD_ERASE_FAILED;
+		} else {
+			instr->state = MTD_ERASE_DONE;
+			err = 0;
+		}
+	}
+
+	DEBUG(3, "blkmtd: erase: checking callback\n");
  erase_callback:
-  if (instr->callback) {
-    (*(instr->callback))(instr);
-  }
-  DEBUG(2, "blkmtd: erase: finished (err = %d)\n", err);
-  return err;
+	if (instr->callback) {
+		(*(instr->callback))(instr);
+	}
+	DEBUG(2, "blkmtd: erase: finished (err = %d)\n", err);
+	return err;
 }
 
 
 /* read a range of the data via the page cache */
 static int blkmtd_read(struct mtd_info *mtd, loff_t from, size_t len,
-	     size_t *retlen, u_char *buf)
+		       size_t *retlen, u_char *buf)
 {
-  mtd_raw_dev_data_t *rawdevice = mtd->priv;
-  int err = 0;
-  int offset;
-  int pagenr, pages;
-
-  *retlen = 0;
-
-  DEBUG(2, "blkmtd: read: dev = `%s' from = %ld len = %d buf = %p\n",
-	bdevname(rawdevice->binding->bd_dev), (long int)from, len, buf);
-
-  pagenr = from >> PAGE_SHIFT;
-  offset = from - (pagenr << PAGE_SHIFT);
-  
-  pages = (offset+len+PAGE_SIZE-1) >> PAGE_SHIFT;
-  DEBUG(3, "blkmtd: read: pagenr = %d offset = %d, pages = %d\n", pagenr, offset, pages);
-
-  /* just loop through each page, getting it via readpage() - slow but easy */
-  while(pages) {
-    struct page *page;
-    int cpylen;
-    DEBUG(3, "blkmtd: read: looking for page: %d\n", pagenr);
-    page = read_cache_page(&rawdevice->as, pagenr, (filler_t *)blkmtd_readpage, rawdevice);
-    if(IS_ERR(page)) {
-      return PTR_ERR(page);
-    }
-    wait_on_page(page);
-    if(!Page_Uptodate(page)) {
-      /* error reading page */
-      printk("blkmtd: read: page not uptodate\n");
-      page_cache_release(page);
-      return -EIO;
-    }
-
-    cpylen = (PAGE_SIZE > len) ? len : PAGE_SIZE;
-    if(offset+cpylen > PAGE_SIZE)
-      cpylen = PAGE_SIZE-offset;
-    
-    memcpy(buf + *retlen, page_address(page) + offset, cpylen);
-    offset = 0;
-    len -= cpylen;
-    *retlen += cpylen;
-    pagenr++;
-    pages--;
-    page_cache_release(page);
-  }
-  
-  DEBUG(2, "blkmtd: end read: retlen = %d, err = %d\n", *retlen, err);
-  return err;
+	struct blkmtd_dev *dev = mtd->priv;
+	int err = 0;
+	int offset;
+	int pagenr, pages;
+	struct page **pagelst;
+	int *pagenrs;
+	int i;
+
+	*retlen = 0;
+
+	DEBUG(2, "blkmtd: read: dev = `%s' from = %ld len = %d buf = %p\n",
+	      bdevname(dev->binding->bd_dev), (long int)from, len, buf);
+
+	pagenr = from >> PAGE_SHIFT;
+	offset = from - (pagenr << PAGE_SHIFT);
+
+	pages = (offset+len+PAGE_SIZE-1) >> PAGE_SHIFT;
+	DEBUG(3, "blkmtd: read: pagenr = %d offset = %d, pages = %d\n",
+	      pagenr, offset, pages);
+
+	pagelst = kmalloc(sizeof(struct page *) * pages, GFP_KERNEL);
+	if(!pagelst)
+		return -ENOMEM;
+	pagenrs = kmalloc(sizeof(int) * pages, GFP_KERNEL);
+	if(!pagenrs) {
+		kfree(pagelst);
+		return -ENOMEM;
+	}
+	for(i = 0; i < pages; i++)
+		pagenrs[i] = pagenr+i;
+
+	err = read_pages(dev, pagenrs, pagelst, pages);
+	if(err)
+		goto readerr;
+
+	pagenr = 0;
+	while(pages) {
+		struct page *page;
+		int cpylen;
+
+		DEBUG(3, "blkmtd: read: looking for page: %d\n", pagenr);
+		page = pagelst[pagenr];
+
+		cpylen = (PAGE_SIZE > len) ? len : PAGE_SIZE;
+		if(offset+cpylen > PAGE_SIZE)
+			cpylen = PAGE_SIZE-offset;
+
+		memcpy(buf + *retlen, page_address(page) + offset, cpylen);
+		offset = 0;
+		len -= cpylen;
+		*retlen += cpylen;
+		pagenr++;
+		pages--;
+		unlock_page(page);
+		if(!PageDirty(page))
+			page_cache_release(page);
+	}
+
+ readerr:
+	kfree(pagelst);
+	kfree(pagenrs);
+	DEBUG(2, "blkmtd: end read: retlen = %d, err = %d\n", *retlen, err);
+	return err;
 }
 
-    
-/* write a range of the data via the page cache.
- *
- * Basic operation. break the write into three parts. 
- *
- * 1. From a page unaligned start up until the next page boundary
- * 2. Page sized, page aligned blocks
- * 3. From end of last aligned block to end of range
- *
- * 1,3 are read via the page cache and readpage() since these are partial
- * pages, 2 we just grab pages from the page cache, not caring if they are
- * already in memory or not since they will be completly overwritten.
- *
- */
- 
+
+/* write data to the underlying device */
 static int blkmtd_write(struct mtd_info *mtd, loff_t to, size_t len,
-	      size_t *retlen, const u_char *buf)
+			size_t *retlen, const u_char *buf)
 {
-  mtd_raw_dev_data_t *rawdevice = mtd->priv;
-  int err = 0;
-  int offset;
-  int pagenr;
-  size_t len1 = 0, len2 = 0, len3 = 0;
-  struct page **pages;
-  int pagecnt = 0;
-
-  *retlen = 0;
-  DEBUG(2, "blkmtd: write: dev = `%s' to = %ld len = %d buf = %p\n",
-	bdevname(rawdevice->binding->bd_dev), (long int)to, len, buf);
-
-  /* handle readonly and out of range numbers */
-
-  if(rawdevice->readonly) {
-    printk("blkmtd: error: trying to write to a readonly device %s\n", device);
-    return -EROFS;
-  }
-
-  if(to >= rawdevice->totalsize) {
-    return -ENOSPC;
-  }
-
-  if(to + len > rawdevice->totalsize) {
-    len = (rawdevice->totalsize - to);
-  }
-
-
-  pagenr = to >> PAGE_SHIFT;
-  offset = to - (pagenr << PAGE_SHIFT);
-
-  /* see if we have to do a partial write at the start */
-  if(offset) {
-    if((offset + len) > PAGE_SIZE) {
-      len1 = PAGE_SIZE - offset;
-      len -= len1;
-    } else {
-      len1 = len;
-      len = 0;
-    }
-  }
-
-  /* calculate the length of the other two regions */
-  len3 = len & ~PAGE_MASK;
-  len -= len3;
-  len2 = len;
-
-
-  if(len1)
-    pagecnt++;
-  if(len2)
-    pagecnt += len2 >> PAGE_SHIFT;
-  if(len3)
-    pagecnt++;
-
-  DEBUG(3, "blkmtd: write: len1 = %d len2 = %d len3 = %d pagecnt = %d\n", len1, len2, len3, pagecnt);
-  
-  /* get space for list of pages */
-  pages = kmalloc(pagecnt * sizeof(struct page *), GFP_KERNEL);
-  if(pages == NULL) {
-    return -ENOMEM;
-  }
-  pagecnt = 0;
-
-  if(len1) {
-    /* do partial start region */
-    struct page *page;
-    
-    DEBUG(3, "blkmtd: write: doing partial start, page = %d len = %d offset = %d\n", pagenr, len1, offset);
-    page = read_cache_page(&rawdevice->as, pagenr, (filler_t *)blkmtd_readpage, rawdevice);
-
-    if(IS_ERR(page)) {
-      kfree(pages);
-      return PTR_ERR(page);
-    }
-    memcpy(page_address(page)+offset, buf, len1);
-    pages[pagecnt++] = page;
-    buf += len1;
-    *retlen = len1;
-    err = 0;
-    pagenr++;
-  }
-
-  /* Now do the main loop to a page aligned, n page sized output */
-  if(len2) {
-    int pagesc = len2 >> PAGE_SHIFT;
-    DEBUG(3, "blkmtd: write: whole pages start = %d, count = %d\n", pagenr, pagesc);
-    while(pagesc) {
-      struct page *page;
-
-      /* see if page is in the page cache */
-      DEBUG(3, "blkmtd: write: grabbing page %d from page cache\n", pagenr);
-      page = grab_cache_page(&rawdevice->as, pagenr);
-      DEBUG(3, "blkmtd: write: got page %d from page cache\n", pagenr);
-      if(!page) {
-	printk("blkmtd: write: cant grab cache page %d\n", pagenr);
-	err = -EIO;
-	goto write_err;
-      }
-      memcpy(page_address(page), buf, PAGE_SIZE);
-      pages[pagecnt++] = page;
-      UnlockPage(page);
-      SetPageUptodate(page);
-      pagenr++;
-      pagesc--;
-      buf += PAGE_SIZE;
-      *retlen += PAGE_SIZE;
-    }
-  }
-
-
-  if(len3) {
-    /* do the third region */
-    struct page *page;
-    DEBUG(3, "blkmtd: write: doing partial end, page = %d len = %d\n", pagenr, len3);
-    page = read_cache_page(&rawdevice->as, pagenr, (filler_t *)blkmtd_readpage, rawdevice);
-    if(IS_ERR(page)) {
-      err = PTR_ERR(page);
-      goto write_err;
-    }
-    memcpy(page_address(page), buf, len3);
-    DEBUG(3, "blkmtd: write: writing out partial end\n");
-    pages[pagecnt++] = page;
-    *retlen += len3;
-    err = 0;
-  }
-  DEBUG(2, "blkmtd: write: end, retlen = %d, err = %d\n", *retlen, err);
-  /* submit it to the write task */
-  err = queue_page_write(rawdevice, pages, to >> PAGE_SHIFT, pagecnt, 0);
-  if(!err) {
-    while(pagecnt--) {
-      SetPageUptodate(pages[pagecnt]);
-      flush_dcache_page(pages[pagecnt]);
-      page_cache_release(pages[pagecnt]);
-    }
-    kfree(pages);
-    return 0;
-  }
-
- write_err:
-  while(--pagecnt) {
-    SetPageError(pages[pagecnt]);
-    page_cache_release(pages[pagecnt]);
-  }
-  kfree(pages);
-  return err;
+	struct blkmtd_dev *dev = mtd->priv;
+	int err;
+
+	*retlen = 0;
+	if(!len)
+		return 0;
+
+	DEBUG(2, "blkmtd: write: dev = `%s' to = %ld len = %d buf = %p\n",
+	      bdevname(dev->binding->bd_dev), (long int)to, len, buf);
+
+	/* handle readonly and out of range numbers */
+
+	if(!dev->wr_buf) {
+		err("error: trying to write to a readonly device %s", mtd->name);
+		return -EROFS;
+	}
+
+	if(to >= mtd->size) {
+		return -ENOSPC;
+	}
+
+	if(to + len > mtd->size) {
+		len = (mtd->size - to);
+	}
+
+	err = write_pages(dev, buf, to, len, retlen);
+	if(err < 0)
+		*retlen = 0;
+	else
+		err = 0;
+	DEBUG(2, "blkmtd: write: end, err = %d\n", err);
+	return err;
 }
 
 
 /* sync the device - wait until the write queue is empty */
 static void blkmtd_sync(struct mtd_info *mtd)
 {
-  DECLARE_WAITQUEUE(wait, current);
-  mtd_raw_dev_data_t *rawdevice = mtd->priv;
-  if(rawdevice->readonly)
-    return;
-
-  DEBUG(2, "blkmtd: sync: called\n");
-
- stuff_inq:
-  spin_lock(&mbd_writeq_lock);
-  if(write_queue_cnt) {
-    spin_unlock(&mbd_writeq_lock);
-    current->state = TASK_UNINTERRUPTIBLE;
-    add_wait_queue(&mtbd_sync_wq, &wait);
-    DEBUG(3, "blkmtd: sync: waking up task\n");
-    wake_up_interruptible(&thr_wq);
-    schedule();
-    current->state = TASK_RUNNING;
-    remove_wait_queue(&mtbd_sync_wq, &wait);
-    DEBUG(3, "blkmtd: sync: waking up after write task\n");
-    goto stuff_inq;
-  }
-  spin_unlock(&mbd_writeq_lock);
+	struct blkmtd_dev *dev = mtd->priv;
+	struct kiobuf *iobuf = dev->wr_buf;
 
-  DEBUG(2, "blkmtd: sync: finished\n");
+	DEBUG(2, "blkmtd: sync: called\n");
+	if(iobuf == NULL)
+		return;
+
+	DEBUG(3, "blkmtd: kiovec: length = %d nr_pages = %d\n",
+	      iobuf->length, iobuf->nr_pages);
+	down(&dev->wrbuf_mutex);
+	if(iobuf->nr_pages)
+		commit_pages(dev);
+	up(&dev->wrbuf_mutex);
 }
 
 
 #ifdef BLKMTD_PROC_DEBUG
 /* procfs stuff */
-static int blkmtd_proc_read(char *page, char **start, off_t off, int count, int *eof, void *data)
+static int blkmtd_proc_read(char *page, char **start, off_t off,
+			    int count, int *eof, void *data)
+{
+	int len;
+	struct list_head *temp1, *temp2;
+
+	MOD_INC_USE_COUNT;
+
+	/* Count the size of the page lists */
+
+	len = sprintf(page, "dev\twr_idx\tmax_idx\tnrpages\tclean\tdirty\tlocked\tlru\n");
+	list_for_each_safe(temp1, temp2, &blkmtd_device_list) {
+		struct blkmtd_dev *dev = list_entry(temp1,  struct blkmtd_dev,
+						    list);
+		struct list_head *temp;
+		struct page *pagei;
+
+		int clean = 0, dirty = 0, locked = 0, lru = 0;
+		/* Count the size of the page lists */
+		list_for_each(temp, &dev->binding->bd_inode->i_mapping->clean_pages) {
+			pagei = list_entry(temp, struct page, list);
+			clean++;
+			if(PageLocked(pagei))
+				locked++;
+			if(PageDirty(pagei))
+				dirty++;
+			if(PageLRU(pagei))
+				lru++;
+		}
+		list_for_each(temp, &dev->binding->bd_inode->i_mapping->dirty_pages) {
+			pagei = list_entry(temp, struct page, list);
+			if(PageLocked(pagei))
+				locked++;
+			if(PageDirty(pagei))
+				dirty++;
+			if(PageLRU(pagei))
+				lru++;
+		}
+		list_for_each(temp, &dev->binding->bd_inode->i_mapping->locked_pages) {
+			pagei = list_entry(temp, struct page, list);
+			if(PageLocked(pagei))
+				locked++;
+			if(PageDirty(pagei))
+				dirty++;
+			if(PageLRU(pagei))
+				lru++;
+		}
+
+		len += sprintf(page+len, "mtd%d:\t%ld\t%d\t%ld\t%d\t%d\t%d\t%d\n",
+			       dev->mtd_info.index,
+			       (dev->wr_buf && dev->wr_buf->nr_pages) ?
+			       dev->wr_buf->blocks[dev->wr_buf->nr_pages-1] : 0,
+			       (dev->wr_buf) ? dev->wr_buf->nr_pages : 0,
+			       dev->binding->bd_inode->i_mapping->nrpages,
+			       clean, dirty, locked, lru);
+	}
+
+	if(len <= count)
+		*eof = 1;
+
+	MOD_DEC_USE_COUNT;
+	return len;
+}
+#endif
+
+
+static void free_device(struct blkmtd_dev *dev)
 {
-  int clean = 0, dirty = 0, locked = 0;
-  struct list_head *temp;
-  int i, len, pages = 0, cnt;
-  MOD_INC_USE_COUNT;
-  spin_lock(&mbd_writeq_lock);
-  cnt = write_queue_cnt;
-  i = write_queue_tail;
-  while(cnt) {
-    if(!write_queue[i].iserase)
-      pages += write_queue[i].pagecnt;
-    i++;
-    i %= write_queue_sz;
-    cnt--;
-  }
-
-  /* Count the size of the page lists */
-  list_for_each(temp, &mtd_rawdevice->as.clean_pages) {
-    clean++;
-  }
-  list_for_each(temp, &mtd_rawdevice->as.dirty_pages) {
-    dirty++;
-  }
-  list_for_each(temp, &mtd_rawdevice->as.locked_pages) {
-    locked++;
-  }
-
-  len = sprintf(page, "Write queue head: %d\nWrite queue tail: %d\n"
-		"Write queue count: %d\nPages in queue: %d (%dK)\n"
-		"Clean Pages: %d\nDirty Pages: %d\nLocked Pages: %d\n"
-		"nrpages: %ld\n",
-		write_queue_head, write_queue_tail, write_queue_cnt,
-		pages, pages << (PAGE_SHIFT-10), clean, dirty, locked,
-		mtd_rawdevice->as.nrpages);
-  if(len <= count)
-    *eof = 1;
-  spin_unlock(&mbd_writeq_lock);
-  MOD_DEC_USE_COUNT;
-  return len;
+	DEBUG(2, "blkmtd: free_device() dev = %p\n", dev);
+	if(dev) {
+		del_mtd_device(&dev->mtd_info);
+		info("mtd%d: [%s] removed", dev->mtd_info.index,
+		     dev->mtd_info.name + strlen("blkmtd: "));
+		if(dev->mtd_info.eraseregions)
+			kfree(dev->mtd_info.eraseregions);
+		if(dev->mtd_info.name)
+			kfree(dev->mtd_info.name);
+
+		if(dev->rd_buf) {
+			dev->rd_buf->locked = 0;
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2,4,4)
+			if(dev->rd_buf->blocks)
+				kfree(dev->rd_buf->blocks);
+#endif
+			free_kiovec(1, &dev->rd_buf);
+		}
+		if(dev->wr_buf) {
+			dev->wr_buf->locked = 0;
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2,4,4)			
+			if(dev->wr_buf->blocks)
+				kfree(dev->rw_buf->blocks);
+#endif
+			free_kiovec(1, &dev->wr_buf);
+		}
+
+		if(dev->binding) {
+			kdev_t kdev = to_kdev_t(dev->binding->bd_dev);
+			invalidate_inode_pages(dev->binding->bd_inode);
+			set_blocksize(kdev, 1 << 10);
+			blkdev_put(dev->binding, BDEV_RAW);
+		}
+		kfree(dev);
+	}
 }
+
+
+/* For a given size and initial erase size, calculate the number
+ * and size of each erase region. Goes round the loop twice,
+ * once to find out how many regions, then allocates space,
+ * then round the loop again to fill it in.
+ */
+static struct mtd_erase_region_info *calc_erase_regions(
+	size_t erase_size, size_t total_size, int *regions)
+{
+	struct mtd_erase_region_info *info = NULL;
+
+	DEBUG(2, "calc_erase_regions, es = %d size = %d regions = %d\n",
+	      erase_size, total_size, *regions);
+	/* Make any user specified erasesize be a power of 2
+	   and at least PAGE_SIZE */
+	if(erase_size) {
+		int es = erase_size;
+		erase_size = 1;
+		while(es != 1) {
+			es >>= 1;
+			erase_size <<= 1;
+		}
+		if(erase_size < PAGE_SIZE)
+			erase_size = PAGE_SIZE;
+	} else {
+		erase_size = CONFIG_MTD_BLKDEV_ERASESIZE;
+	}
+
+	*regions = 0;
+
+	do {
+		int tot_size = total_size;
+		int er_size = erase_size;
+		int count = 0, offset = 0, regcnt = 0;
+
+		while(tot_size) {
+			count = tot_size / er_size;
+			if(count) {
+				tot_size = tot_size % er_size;
+				if(info) {
+					DEBUG(2, "adding to erase info off=%d er=%d cnt=%d\n",
+					      offset, er_size, count);
+					(info+regcnt)->offset = offset;
+					(info+regcnt)->erasesize = er_size;
+					(info+regcnt)->numblocks = count;
+					(*regions)++;
+				}
+				regcnt++;
+				offset += (count * er_size);
+			}
+			while(er_size > tot_size)
+				er_size >>= 1;
+		}
+		if(info == NULL) {
+			info = kmalloc(regcnt * sizeof(struct mtd_erase_region_info), GFP_KERNEL);
+			if(!info)
+				break;
+		}
+	} while(!(*regions));
+	DEBUG(2, "calc_erase_regions done, es = %d size = %d regions = %d\n",
+	      erase_size, total_size, *regions);
+	return info;
+}
+
+
+extern kdev_t name_to_kdev_t(char *line) __init;
+
+
+static struct blkmtd_dev *add_device(char *devname, int readonly, int erase_size)
+{
+	int maj, min;
+	kdev_t kdev;
+	int mode;
+	struct blkmtd_dev *dev;
+
+#ifdef MODULE
+	struct file *file = NULL;
+	struct inode *inode;
 #endif
 
+	if(!devname)
+		return NULL;
+
+	/* Get a handle on the device */
+	mode = (readonly) ? O_RDONLY : O_RDWR;
+
+#ifdef MODULE
+
+	file = filp_open(devname, mode, 0);
+	if(IS_ERR(file)) {
+		err("error: cant open device %s", devname);
+		DEBUG(2, "blkmtd: filp_open returned %ld\n", PTR_ERR(file));
+		return NULL;
+	}
+
+	/* determine is this is a block device and
+	 * if so get its major and minor numbers
+	 */
+	inode = file->f_dentry->d_inode;
+	if(!S_ISBLK(inode->i_mode)) {
+		err("%s not a block device", devname);
+		filp_close(file, NULL);
+		return NULL;
+	}
+	kdev = inode->i_rdev;
+	filp_close(file, NULL);
+#else
+	kdev = name_to_kdev_t(devname);
+#endif	/* MODULE */
+
+	if(!kdev) {
+		err("bad block device: `%s'", devname);
+		return NULL;
+	}
+
+	maj = MAJOR(kdev);
+	min = MINOR(kdev);
+	DEBUG(1, "blkmtd: found a block device major = %d, minor = %d\n",
+	      maj, min);
+
+	if(maj == MTD_BLOCK_MAJOR) {
+		err("attempting to use an MTD device as a block device");
+		return NULL;
+	}
+
+	DEBUG(1, "blkmtd: devname = %s\n", bdevname(kdev));
+
+	dev = kmalloc(sizeof(struct blkmtd_dev), GFP_KERNEL);
+	if(dev == NULL)
+		return NULL;
+
+	memset(dev, 0, sizeof(struct blkmtd_dev));
+	if(alloc_kiovec(1, &dev->rd_buf)) {
+		err("cant allocate read iobuf");
+		goto devinit_err;
+	}
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2,4,4)
+	dev->rd_buf->blocks = kmalloc(KIO_MAX_SECTORS * sizeof(unsigned long), GFP_KERNEL);
+	if(dev->rd_buf->blocks == NULL) {
+		crit("cant allocate rd_buf blocks");
+		goto devinit_err;
+	}
+#endif
+	
+	if(!readonly) {
+		if(alloc_kiovec(1, &dev->wr_buf)) {
+			err("cant allocate kiobuf - readonly enabled");
+
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2,4,4)
+		} else {
+			dev->wr_buf->blocks = kmalloc(KIO_MAX_SECTORS * sizeof(unsigned long), GFP_KERNEL);
+			if(dev->wr_buf->blocks == NULL) {
+				crit("cant allocate wr_buf blocks - readonly enabled");
+				free_kiovec(1, &iobuf);
+			}
+#endif
+		}
+		if(dev->wr_buf)
+			init_MUTEX(&dev->wrbuf_mutex);
+	}
+
+	/* get the block device */
+	dev->binding = bdget(kdev_t_to_nr(MKDEV(maj, min)));
+	if(blkdev_get(dev->binding, mode, 0, BDEV_RAW))
+		goto devinit_err;
+
+	if(set_blocksize(kdev, PAGE_SIZE)) {
+		err("cant set block size to PAGE_SIZE on %s", bdevname(kdev));
+		goto devinit_err;
+	}
+
+	dev->mtd_info.size = dev->binding->bd_inode->i_size & PAGE_MASK;
+
+	/* Setup the MTD structure */
+	/* make the name contain the block device in */
+	dev->mtd_info.name = kmalloc(sizeof("blkmtd: ") + strlen(devname), GFP_KERNEL);
+	if(dev->mtd_info.name == NULL)
+		goto devinit_err;
+
+	sprintf(dev->mtd_info.name, "blkmtd: %s", devname);
+	dev->mtd_info.eraseregions = calc_erase_regions(erase_size, dev->mtd_info.size,
+							&dev->mtd_info.numeraseregions);
+	if(dev->mtd_info.eraseregions == NULL)
+		goto devinit_err;
+
+	dev->mtd_info.erasesize = dev->mtd_info.eraseregions->erasesize;
+	DEBUG(1, "blkmtd: init: found %d erase regions\n",
+	      dev->mtd_info.numeraseregions);
+
+	if(readonly) {
+		dev->mtd_info.type = MTD_ROM;
+		dev->mtd_info.flags = MTD_CAP_ROM;
+	} else {
+		dev->mtd_info.type = MTD_RAM;
+		dev->mtd_info.flags = MTD_CAP_RAM;
+	}
+	dev->mtd_info.erase = blkmtd_erase;
+	dev->mtd_info.read = blkmtd_read;
+	dev->mtd_info.write = blkmtd_write;
+	dev->mtd_info.sync = blkmtd_sync;
+	dev->mtd_info.point = 0;
+	dev->mtd_info.unpoint = 0;
+	dev->mtd_info.priv = dev;
+	dev->mtd_info.module = THIS_MODULE;
+
+	list_add(&dev->list, &blkmtd_device_list);
+	if (add_mtd_device(&dev->mtd_info)) {
+		/* Device didnt get added, so free the entry */
+		list_del(&dev->list);
+		free_device(dev);
+		return NULL;
+	} else {
+		info("mtd%d: [%s] erase_size = %dKiB %s",
+		     dev->mtd_info.index, dev->mtd_info.name + strlen("blkmtd: "),
+		     dev->mtd_info.erasesize >> 10,
+		     (dev->wr_buf) ? "" : "(read-only)");
+	}
+	
+	return dev;
+
+ devinit_err:
+	free_device(dev);
+	return NULL;
+}
+
 
 /* Cleanup and exit - sync the device and kill of the kernel thread */
-static void __exit cleanup_blkmtd(void)
+static void __devexit cleanup_blkmtd(void)
 {
+	struct list_head *temp1, *temp2;
 #ifdef BLKMTD_PROC_DEBUG
-  if(blkmtd_proc) {
-    remove_proc_entry("blkmtd_debug", NULL);
-  }
+	if(blkmtd_proc) {
+		remove_proc_entry("blkmtd_debug", NULL);
+	}
 #endif
 
-  if (mtd_rawdevice) {
-    /* sync the device */
-    if (!mtd_rawdevice->readonly) {
-      blkmtd_sync(&mtd_rawdevice->mtd_info);
-      write_task_finish = 1;
-      wake_up_interruptible(&thr_wq);
-      down(&thread_sem);
-    }
-    del_mtd_device(&mtd_rawdevice->mtd_info);
-    if(mtd_rawdevice->binding != NULL)
-      blkdev_put(mtd_rawdevice->binding, BDEV_RAW);
-
-    if(mtd_rawdevice->mtd_info.eraseregions)
-      kfree(mtd_rawdevice->mtd_info.eraseregions);
-    if(mtd_rawdevice->mtd_info.name)
-      kfree(mtd_rawdevice->mtd_info.name);
-
-    kfree(mtd_rawdevice);
-  }
-  if(write_queue)
-    kfree(write_queue);
-
-  if(erase_page) {
-    UnlockPage(erase_page);
-    __free_pages(erase_page, 0);
-  }
-  printk("blkmtd: unloaded for %s\n", device);
+	/* Remove the MTD devices */
+	list_for_each_safe(temp1, temp2, &blkmtd_device_list) {
+		struct blkmtd_dev *dev = list_entry(temp1, struct blkmtd_dev,
+						    list);
+		blkmtd_sync(&dev->mtd_info);
+		free_device(dev);
+	}
 }
 
-extern struct module __this_module;
-
 #ifndef MODULE
 
 /* Handle kernel boot params */
@@ -982,335 +961,97 @@
 
 static int __init param_blkmtd_device(char *str)
 {
-  device = str;
-  return 1;
+	int i;
+
+	for(i = 0; i < MAX_DEVICES; i++) {
+		device[i] = str;
+		DEBUG(2, "blkmtd: device setup: %d = %s\n", i, device[i]);
+		strsep(&str, ",");
+	}
+	return 1;
 }
 
 
 static int __init param_blkmtd_erasesz(char *str)
 {
-  erasesz = simple_strtol(str, NULL, 0);
-  return 1;
+	int i;
+	for(i = 0; i < MAX_DEVICES; i++) {
+		char *val = strsep(&str, ",");
+		if(val)
+			erasesz[i] = simple_strtoul(val, NULL, 0);
+		DEBUG(2, "blkmtd: erasesz setup: %d = %d\n", i, erasesz[i]);
+	}
+
+	return 1;
 }
 
 
 static int __init param_blkmtd_ro(char *str)
 {
-  ro = simple_strtol(str, NULL, 0);
-  return 1;
-}
-
+	int i;
+	for(i = 0; i < MAX_DEVICES; i++) {
+		char *val = strsep(&str, ",");
+		if(val)
+			ro[i] = simple_strtoul(val, NULL, 0);
+		DEBUG(2, "blkmtd: ro setup: %d = %d\n", i, ro[i]);
+	}
 
-static int __init param_blkmtd_bs(char *str)
-{
-  bs = simple_strtol(str, NULL, 0);
-  return 1;
+	return 1;
 }
 
 
-static int __init param_blkmtd_count(char *str)
+static int __init param_blkmtd_sync(char *str)
 {
-  count = simple_strtol(str, NULL, 0);
-  return 1;
+	if(str[0] == '1')
+		sync = 1;
+	return 1;
 }
 
 __setup("blkmtd_device=", param_blkmtd_device);
 __setup("blkmtd_erasesz=", param_blkmtd_erasesz);
 __setup("blkmtd_ro=", param_blkmtd_ro);
-__setup("blkmtd_bs=", param_blkmtd_bs);
-__setup("blkmtd_count=", param_blkmtd_count);
+__setup("blkmtd_sync=", param_blkmtd_sync);
 
 #endif
 
 
-/* for a given size and initial erase size, calculate the number and size of each
-   erase region */
-static int __init calc_erase_regions(struct mtd_erase_region_info *info, size_t erase_size, size_t total_size)
-{
-  int count = 0;
-  int offset = 0;
-  int regions = 0;
-
-   while(total_size) {
-     count = total_size / erase_size;
-     if(count) {
-       total_size = total_size % erase_size;
-       if(info) {
-	 info->offset = offset;
-	 info->erasesize = erase_size;
-	 info->numblocks = count;
-	 info++;
-       }
-       offset += (count * erase_size);
-       regions++;
-     }
-     while(erase_size > total_size)
-       erase_size >>= 1;
-   }
-   return regions;
-}
-
-
-extern kdev_t name_to_kdev_t(char *line) __init;
-
 /* Startup */
 static int __init init_blkmtd(void)
 {
-#ifdef MODULE
-  struct file *file = NULL;
-  struct inode *inode;
-#endif
+	int i;
 
-  int maj, min;
-  int i, blocksize, blocksize_bits;
-  loff_t size = 0;
-  int readonly = 0;
-  int erase_size = CONFIG_MTD_BLKDEV_ERASESIZE;
-  kdev_t rdev;
-  int err;
-  int mode;
-  int regions;
-
-  /* Check args */
-  if(device == 0) {
-    printk("blkmtd: error, missing `device' name\n");
-    return -EINVAL;
-  }
-
-  if(ro)
-    readonly = 1;
-
-  if(erasesz)
-    erase_size = erasesz;
-
-  if(wqs) {
-    if(wqs < 16) 
-      wqs = 16;
-    if(wqs > 4*WRITE_QUEUE_SZ)
-      wqs = 4*WRITE_QUEUE_SZ;
-    write_queue_sz = wqs;
-  }
-
-  DEBUG(1, "blkmtd: device = `%s' erase size = %dK readonly = %s queue size = %d\n",
-	device, erase_size, readonly ? "yes" : "no", write_queue_sz);
-  /* Get a handle on the device */
-  mode = (readonly) ? O_RDONLY : O_RDWR;
-
-#ifdef MODULE
+	/* Check args - device[0] is the bare minimum*/
+	if(!device[0]) {
+		err("error: missing `device' name\n");
+		return -EINVAL;
+	}
 
-  file = filp_open(device, mode, 0);
-  if(IS_ERR(file)) {
-    printk("blkmtd: error, cant open device %s\n", device);
-    DEBUG(2, "blkmtd: filp_open returned %ld\n", PTR_ERR(file));
-    return 1;
-  }
-  
-  /* determine is this is a block device and if so get its major and minor
-     numbers */
-  inode = file->f_dentry->d_inode;
-  if(!S_ISBLK(inode->i_mode)) {
-    printk("blkmtd: %s not a block device\n", device);
-    filp_close(file, NULL);
-    return 1;
-  }
-  rdev = inode->i_rdev;
-  filp_close(file, NULL);
-#else
-  rdev = name_to_kdev_t(device);
-#endif
+	for(i = 0; i < MAX_DEVICES; i++)
+		add_device(device[i], ro[i], erasesz[i] << 10);
 
-  maj = MAJOR(rdev);
-  min = MINOR(rdev);
-  DEBUG(1, "blkmtd: found a block device major = %d, minor = %d\n", maj, min);
-
-  if(!rdev) {
-    printk("blkmtd: bad block device: `%s'\n", device);
-    return 1;
-  }
-
-  if(maj == MTD_BLOCK_MAJOR) {
-    printk("blkmtd: attempting to use an MTD device as a block device\n");
-    return 1;
-  }
-
-  DEBUG(1, "blkmtd: devname = %s\n", bdevname(rdev));
-  blocksize = BLOCK_SIZE;
-
-  if(bs) {
-    blocksize = bs;
-  } else {
-    if (blksize_size[maj] && blksize_size[maj][min]) {
-      DEBUG(2, "blkmtd: blksize_size = %d\n", blksize_size[maj][min]);
-      blocksize = blksize_size[maj][min];
-    }
-  }
-  i = blocksize;
-  blocksize_bits = 0;
-  while(i != 1) {
-    blocksize_bits++;
-    i >>= 1;
-  }
-
-  if(count) {
-    size = count;
-  } else {
-    if (blk_size[maj]) {
-      size = ((loff_t) blk_size[maj][min] << BLOCK_SIZE_BITS) >> blocksize_bits;
-    }
-  }
-  size *= blocksize;
-  DEBUG(1, "blkmtd: size = %ld\n", (long int)size);
-
-  if(size == 0) {
-    printk("blkmtd: cant determine size\n");
-    return 1;
-  }
-
-  mtd_rawdevice = (mtd_raw_dev_data_t *)kmalloc(sizeof(mtd_raw_dev_data_t), GFP_KERNEL);
-  if(mtd_rawdevice == NULL) {
-    err = -ENOMEM;
-    goto init_err;
-  }
-  memset(mtd_rawdevice, 0, sizeof(mtd_raw_dev_data_t));
-  /* get the block device */
-  mtd_rawdevice->binding = bdget(kdev_t_to_nr(MKDEV(maj, min)));
-  err = blkdev_get(mtd_rawdevice->binding, mode, 0, BDEV_RAW);
-  if (err) {
-    goto init_err;
-  }
-  mtd_rawdevice->totalsize = size;
-  mtd_rawdevice->sector_size = blocksize;
-  mtd_rawdevice->sector_bits = blocksize_bits;
-  mtd_rawdevice->readonly = readonly;
-
-  /* See if device ends on page boundary */
-  if(size % PAGE_SIZE) {
-    mtd_rawdevice->partial_last_page = size >> PAGE_SHIFT;
-    mtd_rawdevice->last_page_sectors = (size & (PAGE_SIZE-1)) >> blocksize_bits;
-  }
-
-  DEBUG(2, "sector_size = %d, sector_bits = %d, partial_last_page = %d last_page_sectors = %d\n", 
-	mtd_rawdevice->sector_size, mtd_rawdevice->sector_bits,
-	mtd_rawdevice->partial_last_page, mtd_rawdevice->last_page_sectors);
-
-  /* Setup the MTD structure */
-  /* make the name contain the block device in */
-  mtd_rawdevice->mtd_info.name = kmalloc(9 + strlen(device), GFP_KERNEL);
-  if(mtd_rawdevice->mtd_info.name == NULL)
-    goto init_err;
-
-  sprintf(mtd_rawdevice->mtd_info.name, "blkmtd: %s", device);
-  if(readonly) {
-    mtd_rawdevice->mtd_info.type = MTD_ROM;
-    mtd_rawdevice->mtd_info.flags = MTD_CAP_ROM;
-    mtd_rawdevice->mtd_info.erasesize = erase_size << 10;
-  } else {
-    mtd_rawdevice->mtd_info.type = MTD_RAM;
-    mtd_rawdevice->mtd_info.flags = MTD_CAP_RAM;
-    mtd_rawdevice->mtd_info.erasesize = erase_size << 10;
-  }
-  mtd_rawdevice->mtd_info.size = size;
-  mtd_rawdevice->mtd_info.erase = blkmtd_erase;
-  mtd_rawdevice->mtd_info.read = blkmtd_read;
-  mtd_rawdevice->mtd_info.write = blkmtd_write;
-  mtd_rawdevice->mtd_info.sync = blkmtd_sync;
-  mtd_rawdevice->mtd_info.point = 0;
-  mtd_rawdevice->mtd_info.unpoint = 0;
-
-  mtd_rawdevice->mtd_info.priv = mtd_rawdevice;
-  regions = calc_erase_regions(NULL, erase_size << 10, size);
-  DEBUG(1, "blkmtd: init: found %d erase regions\n", regions);
-  mtd_rawdevice->mtd_info.eraseregions = kmalloc(regions * sizeof(struct mtd_erase_region_info), GFP_KERNEL);
-  if(mtd_rawdevice->mtd_info.eraseregions == NULL) {
-    err = -ENOMEM;
-    goto init_err;
-  }
-  mtd_rawdevice->mtd_info.numeraseregions = regions;
-  calc_erase_regions(mtd_rawdevice->mtd_info.eraseregions, erase_size << 10, size);
-
-  /* setup the page cache info */
-  
-  mtd_rawdevice->as.nrpages = 0;
-  INIT_LIST_HEAD(&mtd_rawdevice->as.clean_pages);
-  INIT_LIST_HEAD(&mtd_rawdevice->as.dirty_pages);
-  INIT_LIST_HEAD(&mtd_rawdevice->as.locked_pages);
-  mtd_rawdevice->as.host = NULL;
-  spin_lock_init(&(mtd_rawdevice->as.i_shared_lock));
-
-  mtd_rawdevice->as.a_ops = &blkmtd_aops;
-  mtd_rawdevice->as.i_mmap = NULL;
-  mtd_rawdevice->as.i_mmap_shared = NULL;
-  mtd_rawdevice->as.gfp_mask = GFP_KERNEL;
+	if(list_empty(&blkmtd_device_list))
+		goto init_err;
 
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,2,0)
-  mtd_rawdevice->mtd_info.module = THIS_MODULE;			
-#endif
-  if (add_mtd_device(&mtd_rawdevice->mtd_info)) {
-    err = -EIO;
-    goto init_err;
-  }
-
-  if(!mtd_rawdevice->readonly) {
-    /* Allocate the write queue */
-    write_queue = kmalloc(write_queue_sz * sizeof(mtdblkdev_write_queue_t), GFP_KERNEL);
-    if(!write_queue) {
-      err = -ENOMEM;
-      goto init_err;
-    }
-    /* Set up the erase page */
-    erase_page = alloc_pages(GFP_KERNEL, 0);
-    if(erase_page == NULL) {
-      err = -ENOMEM;
-      goto init_err;
-    }
-    memset(page_address(erase_page), 0xff, PAGE_SIZE);
-    lock_page(erase_page);
-
-    init_waitqueue_head(&thr_wq);
-    init_waitqueue_head(&mtbd_sync_wq);
-    DEBUG(3, "blkmtd: init: kernel task @ %p\n", write_queue_task);
-    DEBUG(2, "blkmtd: init: starting kernel task\n");
-    kernel_thread(write_queue_task, NULL, CLONE_FS | CLONE_FILES | CLONE_SIGHAND);
-    DEBUG(2, "blkmtd: init: started\n");
-    printk("blkmtd loaded: version = %s using %s erase_size = %dK %s\n",
-	   VERSION, device, erase_size, (readonly) ? "(read-only)" : "");
-  }
+	info("version " VERSION);
 
 #ifdef BLKMTD_PROC_DEBUG
-  /* create proc entry */
-  DEBUG(2, "Creating /proc/blkmtd_debug\n");
-  blkmtd_proc = create_proc_read_entry("blkmtd_debug", 0444,
-				       NULL, blkmtd_proc_read, NULL);
-  if(blkmtd_proc == NULL) {
-    printk("Cant create /proc/blkmtd_debug\n");
-  } else {
-    blkmtd_proc->owner = THIS_MODULE;
-  }
+	/* create proc entry */
+	DEBUG(2, "Creating /proc/blkmtd_debug\n");
+	blkmtd_proc = create_proc_read_entry("blkmtd_debug", 0444,
+					     NULL, blkmtd_proc_read, NULL);
+	if(blkmtd_proc == NULL) {
+		err("Cant create /proc/blkmtd_debug");
+	} else {
+		blkmtd_proc->owner = THIS_MODULE;
+	}
 #endif
-  
-  /* Everything is ok if we got here */
-  return 0;
-  
- init_err:
 
-  if(mtd_rawdevice) {
-    if(mtd_rawdevice->mtd_info.eraseregions)
-      kfree(mtd_rawdevice->mtd_info.eraseregions);
-    if(mtd_rawdevice->mtd_info.name)
-      kfree(mtd_rawdevice->mtd_info.name);
-    if(mtd_rawdevice->binding) 
-      blkdev_put(mtd_rawdevice->binding, BDEV_RAW);
-    kfree(mtd_rawdevice);
-  }
-
-  if(write_queue) {
-    kfree(write_queue);
-    write_queue = NULL;
-  }
-
-  if(erase_page) 
-    __free_pages(erase_page, 0);
-  return err;
+	if(!list_empty(&blkmtd_device_list))
+		/* Everything is ok if we got here */
+		return 0;
+
+ init_err:
+	return -EINVAL;
 }
 
 module_init(init_blkmtd);

FUNET's LINUX-ADM group, linux-adm@nic.funet.fi
TCL-scripts by Sam Shen (who was at: slshen@lbl.gov)