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Diffstat (limited to 'drivers/mtd/devices/blkmtd.c')
-rw-r--r--drivers/mtd/devices/blkmtd.c823
1 files changed, 823 insertions, 0 deletions
diff --git a/drivers/mtd/devices/blkmtd.c b/drivers/mtd/devices/blkmtd.c
new file mode 100644
index 000000000000..662e807801ed
--- /dev/null
+++ b/drivers/mtd/devices/blkmtd.c
@@ -0,0 +1,823 @@
+/*
+ * $Id: blkmtd.c,v 1.24 2004/11/16 18:29:01 dwmw2 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: 1.24 $"
+
+/* 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);
+ }
+ ClearPageDirty(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);
+ SetPageDirty(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--;
+ SetPageDirty(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);
+ SetPageDirty(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) {
+ if(dev->mtd_info.eraseregions)
+ kfree(dev->mtd_info.eraseregions);
+ if(dev->mtd_info.name)
+ 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);