Linux v2.6.15-rc7

[pohmelfs.git] / drivers / mtd / devices / blkmtd.c

/*
 * $Id: blkmtd.c,v 1.27 2005/11/07 11:14:24 gleixner Exp $
 *
 * blkmtd.c - use a block device as a fake MTD
 *
 * Author: Simon Evans <spse@secret.org.uk>
 *
 * 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 and mark it dirty and add the page into a BIO which
 *      is then written out.
 *
 *      It can be loaded Read-Only to prevent erases and writes to the
 *      medium.
 *
 */

#include <linux/config.h>
#include <linux/module.h>
#include <linux/fs.h>
#include <linux/blkdev.h>
#include <linux/bio.h>
#include <linux/pagemap.h>
#include <linux/list.h>
#include <linux/init.h>
#include <linux/mtd/mtd.h>


#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)


/* Default erase size in K, always make it a multiple of PAGE_SIZE */
#define CONFIG_MTD_BLKDEV_ERASESIZE (128 << 10) /* 128KiB */
#define VERSION "$Revision: 1.27 $"

/* Info for the block device */
struct blkmtd_dev {
        struct list_head list;
        struct block_device *blkdev;
        struct mtd_info mtd_info;
        struct semaphore wrbuf_mutex;
};


/* Static info about the MTD, used in cleanup_module */
static LIST_HEAD(blkmtd_device_list);


static void blkmtd_sync(struct mtd_info *mtd);

#define MAX_DEVICES 4

/* Module parameters passed by insmod/modprobe */
static char *device[MAX_DEVICES];    /* the block device to use */
static int erasesz[MAX_DEVICES];     /* optional default erase size */
static int ro[MAX_DEVICES];          /* optional read only flag */
static int sync;


MODULE_LICENSE("GPL");
MODULE_AUTHOR("Simon Evans <spse@secret.org.uk>");
MODULE_DESCRIPTION("Emulate an MTD using a block device");
module_param_array(device, charp, NULL, 0);
MODULE_PARM_DESC(device, "block device to use");
module_param_array(erasesz, int, NULL, 0);
MODULE_PARM_DESC(erasesz, "optional erase size to use in KiB. eg 4=4KiB.");
module_param_array(ro, bool, NULL, 0);
MODULE_PARM_DESC(ro, "1=Read only, writes and erases cause errors");
module_param(sync, bool, 0);
MODULE_PARM_DESC(sync, "1=Synchronous writes");


/* completion handler for BIO reads */
static int bi_read_complete(struct bio *bio, unsigned int bytes_done, int error)
{
        if (bio->bi_size)
                return 1;

        complete((struct completion*)bio->bi_private);
        return 0;
}


/* completion handler for BIO writes */
static int bi_write_complete(struct bio *bio, unsigned int bytes_done, int error)
{
        const int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags);
        struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1;

        if (bio->bi_size)
                return 1;

        if(!uptodate)
                err("bi_write_complete: not uptodate\n");

        do {
                struct page *page = bvec->bv_page;
                DEBUG(3, "Cleaning up page %ld\n", page->index);
                if (--bvec >= bio->bi_io_vec)
                        prefetchw(&bvec->bv_page->flags);

                if (uptodate) {
                        SetPageUptodate(page);
                } else {
                        ClearPageUptodate(page);
                        SetPageError(page);
                }
                clear_page_dirty(page);
                unlock_page(page);
                page_cache_release(page);
        } while (bvec >= bio->bi_io_vec);

        complete((struct completion*)bio->bi_private);
        return 0;
}


/* read one page from the block device */
static int blkmtd_readpage(struct blkmtd_dev *dev, struct page *page)
{
        struct bio *bio;
        struct completion event;
        int err = -ENOMEM;

        if(PageUptodate(page)) {
                DEBUG(2, "blkmtd: readpage page %ld is already upto date\n", page->index);
                unlock_page(page);
                return 0;
        }

        ClearPageUptodate(page);
        ClearPageError(page);

        bio = bio_alloc(GFP_KERNEL, 1);
        if(bio) {
                init_completion(&event);
                bio->bi_bdev = dev->blkdev;
                bio->bi_sector = page->index << (PAGE_SHIFT-9);
                bio->bi_private = &event;
                bio->bi_end_io = bi_read_complete;
                if(bio_add_page(bio, page, PAGE_SIZE, 0) == PAGE_SIZE) {
                        submit_bio(READ_SYNC, bio);
                        wait_for_completion(&event);
                        err = test_bit(BIO_UPTODATE, &bio->bi_flags) ? 0 : -EIO;
                        bio_put(bio);
                }
        }

        if(err)
                SetPageError(page);
        else
                SetPageUptodate(page);
        flush_dcache_page(page);
        unlock_page(page);
        return err;
}


/* write out the current BIO and wait for it to finish */
static int blkmtd_write_out(struct bio *bio)
{
        struct completion event;
        int err;

        if(!bio->bi_vcnt) {
                bio_put(bio);
                return 0;
        }

        init_completion(&event);
        bio->bi_private = &event;
        bio->bi_end_io = bi_write_complete;
        submit_bio(WRITE_SYNC, bio);
        wait_for_completion(&event);
        DEBUG(3, "submit_bio completed, bi_vcnt = %d\n", bio->bi_vcnt);
        err = test_bit(BIO_UPTODATE, &bio->bi_flags) ? 0 : -EIO;
        bio_put(bio);
        return err;
}


/**
 * blkmtd_add_page - add a page to the current BIO
 * @bio: bio to add to (NULL to alloc initial bio)
 * @blkdev: block device
 * @page: page to add
 * @pagecnt: pages left to add
 *
 * Adds a page to the current bio, allocating it if necessary. If it cannot be
 * added, the current bio is written out and a new one is allocated. Returns
 * the new bio to add or NULL on error
 */
static struct bio *blkmtd_add_page(struct bio *bio, struct block_device *blkdev,
                                   struct page *page, int pagecnt)
{

 retry:
        if(!bio) {
                bio = bio_alloc(GFP_KERNEL, pagecnt);
                if(!bio)
                        return NULL;
                bio->bi_sector = page->index << (PAGE_SHIFT-9);
                bio->bi_bdev = blkdev;
        }

        if(bio_add_page(bio, page, PAGE_SIZE, 0) != PAGE_SIZE) {
                blkmtd_write_out(bio);
                bio = NULL;
                goto retry;
        }
        return bio;
}


/**
 * 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 bio and then written
 * out.
 */
static int write_pages(struct blkmtd_dev *dev, const u_char *buf, loff_t to,
                    size_t len, size_t *retlen)
{
        int pagenr, offset;
        size_t start_len = 0, end_len;
        int pagecnt = 0;
        int err = 0;
        struct bio *bio = NULL;
        size_t thislen = 0;

        pagenr = to >> PAGE_SHIFT;
        offset = to & ~PAGE_MASK;

        DEBUG(2, "blkmtd: write_pages: buf = %p to = %ld len = %zd pagenr = %d offset = %d\n",
              buf, (long)to, len, pagenr, offset);

        /* 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;
        }

        /* calculate the length of the other two regions */
        end_len = len & ~PAGE_MASK;
        len -= end_len;

        if(start_len)
                pagecnt++;

        if(len)
                pagecnt += len >> PAGE_SHIFT;

        if(end_len)
                pagecnt++;

        down(&dev->wrbuf_mutex);

        DEBUG(3, "blkmtd: write: start_len = %zd len = %zd end_len = %zd pagecnt = %d\n",
              start_len, len, end_len, pagecnt);

        if(start_len) {
                /* do partial start region */
                struct page *page;

                DEBUG(3, "blkmtd: write: doing partial start, page = %d len = %zd offset = %d\n",
                      pagenr, start_len, offset);

                BUG_ON(!buf);
                page = read_cache_page(dev->blkdev->bd_inode->i_mapping, pagenr, (filler_t *)blkmtd_readpage, dev);
                lock_page(page);
                if(PageDirty(page)) {
                        err("to = %lld start_len = %zd len = %zd end_len = %zd pagenr = %d\n",
                            to, start_len, len, end_len, pagenr);
                        BUG();
                }
                memcpy(page_address(page)+offset, buf, start_len);
                set_page_dirty(page);
                SetPageUptodate(page);
                buf += start_len;
                thislen = start_len;
                bio = blkmtd_add_page(bio, dev->blkdev, page, pagecnt);
                if(!bio) {
                        err = -ENOMEM;
                        err("bio_add_page failed\n");
                        goto write_err;
                }
                pagecnt--;
                pagenr++;
        }

        /* 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->blkdev->bd_inode->i_mapping, pagenr);
                        if(PageDirty(page)) {
                                BUG();
                        }
                        if(!page) {
                                warn("write: cannot 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;
                        }
                        bio = blkmtd_add_page(bio, dev->blkdev, page, pagecnt);
                        if(!bio) {
                                err = -ENOMEM;
                                err("bio_add_page failed\n");
                                goto write_err;
                        }
                        pagenr++;
                        pagecnt--;
                        set_page_dirty(page);
                        SetPageUptodate(page);
                        pagesc--;
                        thislen += PAGE_SIZE;
                }
        }

        if(end_len) {
                /* do the third region */
                struct page *page;
                DEBUG(3, "blkmtd: write: doing partial end, page = %d len = %zd\n",
                      pagenr, end_len);
                BUG_ON(!buf);
                page = read_cache_page(dev->blkdev->bd_inode->i_mapping, pagenr, (filler_t *)blkmtd_readpage, dev);
                lock_page(page);
                if(PageDirty(page)) {
                        err("to = %lld start_len = %zd len = %zd end_len = %zd pagenr = %d\n",
                            to, start_len, len, end_len, pagenr);
                        BUG();
                }
                memcpy(page_address(page), buf, end_len);
                set_page_dirty(page);
                SetPageUptodate(page);
                DEBUG(3, "blkmtd: write: writing out partial end\n");
                thislen += end_len;
                bio = blkmtd_add_page(bio, dev->blkdev, page, pagecnt);
                if(!bio) {
                        err = -ENOMEM;
                        err("bio_add_page failed\n");
                        goto write_err;
                }
                pagenr++;
        }

        DEBUG(3, "blkmtd: write: got %d vectors to write\n", bio->bi_vcnt);
 write_err:
        if(bio)
                blkmtd_write_out(bio);

        DEBUG(2, "blkmtd: write: end, retlen = %zd, err = %d\n", *retlen, err);
        up(&dev->wrbuf_mutex);

        if(retlen)
                *retlen = thislen;
        return err;
}


/* erase a specified part of the device */
static int blkmtd_erase(struct mtd_info *mtd, struct erase_info *instr)
{
        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;
        size_t retlen;

        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%zx len = 0x%lx\n",
              mtd->name+9, 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%08zX", len, from);
                instr->state = MTD_ERASE_FAILED;
                err = -EIO;
        }

        if(instr->state != MTD_ERASE_FAILED) {
                /* do the erase */
                DEBUG(3, "Doing erase from = %zd len = %ld\n", from, len);
                err = write_pages(dev, NULL, from, len, &retlen);
                if(err || retlen != len) {
                        err("erase failed err = %d", err);
                        instr->state = MTD_ERASE_FAILED;
                } else {
                        instr->state = MTD_ERASE_DONE;
                }
        }

        DEBUG(3, "blkmtd: erase: checking callback\n");
        mtd_erase_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)
{
        struct blkmtd_dev *dev = mtd->priv;
        int err = 0;
        int offset;
        int pagenr, pages;
        size_t thislen = 0;

        DEBUG(2, "blkmtd: read: dev = `%s' from = %lld len = %zd buf = %p\n",
              mtd->name+9, from, len, buf);

        if(from > mtd->size)
                return -EINVAL;
        if(from + len > mtd->size)
                len = mtd->size - from;

        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);

        while(pages) {
                struct page *page;
                int cpylen;

                DEBUG(3, "blkmtd: read: looking for page: %d\n", pagenr);
                page = read_cache_page(dev->blkdev->bd_inode->i_mapping, pagenr, (filler_t *)blkmtd_readpage, dev);
                if(IS_ERR(page)) {
                        err = -EIO;
                        goto readerr;
                }

                cpylen = (PAGE_SIZE > len) ? len : PAGE_SIZE;
                if(offset+cpylen > PAGE_SIZE)
                        cpylen = PAGE_SIZE-offset;

                memcpy(buf + thislen, page_address(page) + offset, cpylen);
                offset = 0;
                len -= cpylen;
                thislen += cpylen;
                pagenr++;
                pages--;
                if(!PageDirty(page))
                        page_cache_release(page);
        }

 readerr:
        if(retlen)
                *retlen = thislen;
        DEBUG(2, "blkmtd: end read: retlen = %zd, err = %d\n", thislen, err);
        return err;
}


/* 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)
{
        struct blkmtd_dev *dev = mtd->priv;
        int err;

        if(!len)
                return 0;

        DEBUG(2, "blkmtd: write: dev = `%s' to = %lld len = %zd buf = %p\n",
              mtd->name+9, to, len, buf);

        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)
                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)
{
        /* Currently all writes are synchronous */
}


static void free_device(struct blkmtd_dev *dev)
{
        DEBUG(2, "blkmtd: free_device() dev = %p\n", dev);
        if(dev) {
                kfree(dev->mtd_info.eraseregions);
                kfree(dev->mtd_info.name);
                if(dev->blkdev) {
                        invalidate_inode_pages(dev->blkdev->bd_inode->i_mapping);
                        close_bdev_excl(dev->blkdev);
                }
                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 = %zd size = %zd 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 = %zd size = %zd regions = %d\n",
              erase_size, total_size, *regions);
        return info;
}


extern dev_t __init name_to_dev_t(const char *line);

static struct blkmtd_dev *add_device(char *devname, int readonly, int erase_size)
{
        struct block_device *bdev;
        int mode;
        struct blkmtd_dev *dev;

        if(!devname)
                return NULL;

        /* Get a handle on the device */


#ifdef MODULE
        mode = (readonly) ? O_RDONLY : O_RDWR;
        bdev = open_bdev_excl(devname, mode, NULL);
#else
        mode = (readonly) ? FMODE_READ : FMODE_WRITE;
        bdev = open_by_devnum(name_to_dev_t(devname), mode);
#endif
        if(IS_ERR(bdev)) {
                err("error: cannot open device %s", devname);
                DEBUG(2, "blkmtd: opening bdev returned %ld\n", PTR_ERR(bdev));
                return NULL;
        }

        DEBUG(1, "blkmtd: found a block device major = %d, minor = %d\n",
              MAJOR(bdev->bd_dev), MINOR(bdev->bd_dev));

        if(MAJOR(bdev->bd_dev) == MTD_BLOCK_MAJOR) {
                err("attempting to use an MTD device as a block device");
                blkdev_put(bdev);
                return NULL;
        }

        dev = kmalloc(sizeof(struct blkmtd_dev), GFP_KERNEL);
        if(dev == NULL) {
                blkdev_put(bdev);
                return NULL;
        }

        memset(dev, 0, sizeof(struct blkmtd_dev));
        dev->blkdev = bdev;
        if(!readonly) {
                init_MUTEX(&dev->wrbuf_mutex);
        }

        dev->mtd_info.size = dev->blkdev->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.write = blkmtd_write;
                dev->mtd_info.writev = default_mtd_writev;
                dev->mtd_info.sync = blkmtd_sync;
        }
        dev->mtd_info.read = blkmtd_read;
        dev->mtd_info.readv = default_mtd_readv;
        dev->mtd_info.priv = dev;
        dev->mtd_info.owner = 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);
                goto devinit_err;
        } else {
                info("mtd%d: [%s] erase_size = %dKiB %s",
                     dev->mtd_info.index, dev->mtd_info.name + strlen("blkmtd: "),
                     dev->mtd_info.erasesize >> 10,
                     readonly ? "(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 __devexit cleanup_blkmtd(void)
{
        struct list_head *temp1, *temp2;

        /* 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);
                del_mtd_device(&dev->mtd_info);
                info("mtd%d: [%s] removed", dev->mtd_info.index,
                     dev->mtd_info.name + strlen("blkmtd: "));
                list_del(&dev->list);
                free_device(dev);
        }
}

#ifndef MODULE

/* Handle kernel boot params */


static int __init param_blkmtd_device(char *str)
{
        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)
{
        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)
{
        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]);
        }

        return 1;
}


static int __init param_blkmtd_sync(char *str)
{
        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_sync=", param_blkmtd_sync);

#endif


/* Startup */
static int __init init_blkmtd(void)
{
        int i;

        info("version " VERSION);
        /* Check args - device[0] is the bare minimum*/
        if(!device[0]) {
                err("error: missing `device' name\n");
                return -EINVAL;
        }

        for(i = 0; i < MAX_DEVICES; i++)
                add_device(device[i], ro[i], erasesz[i] << 10);

        if(list_empty(&blkmtd_device_list))
                return -EINVAL;

        return 0;
}

module_init(init_blkmtd);
module_exit(cleanup_blkmtd);