--- /dev/null
+--- a/drivers/mtd/devices/block2mtd.c
++++ b/drivers/mtd/devices/block2mtd.c
+@@ -30,6 +30,8 @@ struct block2mtd_dev {
+ struct block_device *blkdev;
+ struct mtd_info mtd;
+ struct mutex write_mutex;
++ rwlock_t bdev_mutex;
++ char devname[0];
+ };
+
+
+@@ -82,6 +84,12 @@ static int block2mtd_erase(struct mtd_in
+ size_t len = instr->len;
+ int err;
+
++ read_lock(&dev->bdev_mutex);
++ if (!dev->blkdev) {
++ err = -EINVAL;
++ goto done;
++ }
++
+ instr->state = MTD_ERASING;
+ mutex_lock(&dev->write_mutex);
+ err = _block2mtd_erase(dev, from, len);
+@@ -93,6 +101,10 @@ static int block2mtd_erase(struct mtd_in
+ instr->state = MTD_ERASE_DONE;
+
+ mtd_erase_callback(instr);
++
++done:
++ read_unlock(&dev->bdev_mutex);
++
+ return err;
+ }
+
+@@ -104,10 +116,14 @@ static int block2mtd_read(struct mtd_inf
+ struct page *page;
+ int index = from >> PAGE_SHIFT;
+ int offset = from & (PAGE_SIZE-1);
+- int cpylen;
++ int cpylen, err = 0;
++
++ read_lock(&dev->bdev_mutex);
++ if (!dev->blkdev || (from > mtd->size)) {
++ err = -EINVAL;
++ goto done;
++ }
+
+- if (from > mtd->size)
+- return -EINVAL;
+ if (from + len > mtd->size)
+ len = mtd->size - from;
+
+@@ -122,10 +138,14 @@ static int block2mtd_read(struct mtd_inf
+ len = len - cpylen;
+
+ page = page_read(dev->blkdev->bd_inode->i_mapping, index);
+- if (!page)
+- return -ENOMEM;
+- if (IS_ERR(page))
+- return PTR_ERR(page);
++ if (!page) {
++ err = -ENOMEM;
++ goto done;
++ }
++ if (IS_ERR(page)) {
++ err = PTR_ERR(page);
++ goto done;
++ }
+
+ memcpy(buf, page_address(page) + offset, cpylen);
+ page_cache_release(page);
+@@ -136,7 +156,10 @@ static int block2mtd_read(struct mtd_inf
+ offset = 0;
+ index++;
+ }
+- return 0;
++
++done:
++ read_unlock(&dev->bdev_mutex);
++ return err;
+ }
+
+
+@@ -188,12 +211,22 @@ static int block2mtd_write(struct mtd_in
+ size_t *retlen, const u_char *buf)
+ {
+ struct block2mtd_dev *dev = mtd->priv;
+- int err;
++ int err = 0;
++
++ read_lock(&dev->bdev_mutex);
++ if (!dev->blkdev) {
++ err = -EINVAL;
++ goto done;
++ }
+
+ if (!len)
+- return 0;
+- if (to >= mtd->size)
+- return -ENOSPC;
++ goto done;
++
++ if (to >= mtd->size) {
++ err = -ENOSPC;
++ goto done;
++ }
++
+ if (to + len > mtd->size)
+ len = mtd->size - to;
+
+@@ -202,6 +235,9 @@ static int block2mtd_write(struct mtd_in
+ mutex_unlock(&dev->write_mutex);
+ if (err > 0)
+ err = 0;
++
++done:
++ read_unlock(&dev->bdev_mutex);
+ return err;
+ }
+
+@@ -210,52 +246,29 @@ static int block2mtd_write(struct mtd_in
+ static void block2mtd_sync(struct mtd_info *mtd)
+ {
+ struct block2mtd_dev *dev = mtd->priv;
+- sync_blockdev(dev->blkdev);
+- return;
+-}
+-
+-
+-static void block2mtd_free_device(struct block2mtd_dev *dev)
+-{
+- if (!dev)
+- return;
+-
+- kfree(dev->mtd.name);
+
+- if (dev->blkdev) {
+- invalidate_mapping_pages(dev->blkdev->bd_inode->i_mapping,
+- 0, -1);
+- close_bdev_exclusive(dev->blkdev, FMODE_READ|FMODE_WRITE);
+- }
++ read_lock(&dev->bdev_mutex);
++ if (dev->blkdev)
++ sync_blockdev(dev->blkdev);
++ read_unlock(&dev->bdev_mutex);
+
+- kfree(dev);
++ return;
+ }
+
+
+-/* FIXME: ensure that mtd->size % erase_size == 0 */
+-static struct block2mtd_dev *add_device(char *devname, int erase_size, const char *mtdname)
++static int _open_bdev(struct block2mtd_dev *dev)
+ {
+ struct block_device *bdev;
+- struct block2mtd_dev *dev;
+- struct mtd_partition *part;
+- char *name;
+-
+- if (!devname)
+- return NULL;
+-
+- dev = kzalloc(sizeof(struct block2mtd_dev), GFP_KERNEL);
+- if (!dev)
+- return NULL;
+
+ /* Get a handle on the device */
+- bdev = open_bdev_exclusive(devname, FMODE_READ|FMODE_WRITE, NULL);
++ bdev = open_bdev_exclusive(dev->devname, FMODE_READ|FMODE_WRITE, NULL);
+ #ifndef MODULE
+ if (IS_ERR(bdev)) {
+
+ /* We might not have rootfs mounted at this point. Try
+ to resolve the device name by other means. */
+
+- dev_t devt = name_to_dev_t(devname);
++ dev_t devt = name_to_dev_t(dev->devname);
+ if (devt) {
+ bdev = open_by_devnum(devt, FMODE_WRITE | FMODE_READ);
+ }
+@@ -263,17 +276,98 @@ static struct block2mtd_dev *add_device(
+ #endif
+
+ if (IS_ERR(bdev)) {
+- ERROR("error: cannot open device %s", devname);
+- goto devinit_err;
++ ERROR("error: cannot open device %s", dev->devname);
++ return 1;
+ }
+ dev->blkdev = bdev;
+
+ if (MAJOR(bdev->bd_dev) == MTD_BLOCK_MAJOR) {
+ ERROR("attempting to use an MTD device as a block device");
+- goto devinit_err;
++ return 1;
+ }
+
++ return 0;
++}
++
++static void _close_bdev(struct block2mtd_dev *dev)
++{
++ struct block_device *bdev;
++
++ if (!dev->blkdev)
++ return;
++
++ bdev = dev->blkdev;
++ invalidate_mapping_pages(dev->blkdev->bd_inode->i_mapping, 0, -1);
++ close_bdev_exclusive(dev->blkdev, FMODE_READ|FMODE_WRITE);
++ dev->blkdev = NULL;
++}
++
++static void block2mtd_free_device(struct block2mtd_dev *dev)
++{
++ if (!dev)
++ return;
++
++ kfree(dev->mtd.name);
++ _close_bdev(dev);
++ kfree(dev);
++}
++
++
++static int block2mtd_refresh(struct mtd_info *mtd)
++{
++ struct block2mtd_dev *dev = mtd->priv;
++ struct block_device *bdev;
++ dev_t devt;
++ int err = 0;
++
++ /* no other mtd function can run at this point */
++ write_lock(&dev->bdev_mutex);
++
++ /* get the device number for the whole disk */
++ devt = MKDEV(MAJOR(dev->blkdev->bd_dev), 0);
++
++ /* close the old block device */
++ _close_bdev(dev);
++
++ /* open the whole disk, issue a partition rescan, then */
++ bdev = open_by_devnum(devt, FMODE_WRITE | FMODE_READ);
++ if (!bdev || !bdev->bd_disk)
++ err = -EINVAL;
++#ifndef CONFIG_MTD_BLOCK2MTD_MODULE
++ else
++ err = rescan_partitions(bdev->bd_disk, bdev);
++#endif
++ if (bdev)
++ close_bdev_exclusive(bdev, FMODE_READ|FMODE_WRITE);
++
++ /* try to open the partition block device again */
++ _open_bdev(dev);
++ write_unlock(&dev->bdev_mutex);
++
++ return err;
++}
++
++/* FIXME: ensure that mtd->size % erase_size == 0 */
++static struct block2mtd_dev *add_device(char *devname, int erase_size, char *mtdname)
++{
++ struct block2mtd_dev *dev;
++ struct mtd_partition *part;
++ char *name;
++
++ if (!devname)
++ return NULL;
++
++ dev = kzalloc(sizeof(struct block2mtd_dev) + strlen(devname) + 1, GFP_KERNEL);
++ if (!dev)
++ return NULL;
++
++ strcpy(dev->devname, devname);
++
++ if (_open_bdev(dev))
++ goto devinit_err;
++
+ mutex_init(&dev->write_mutex);
++ rwlock_init(&dev->bdev_mutex);
+
+ /* Setup the MTD structure */
+ /* make the name contain the block device in */
+@@ -298,6 +392,7 @@ static struct block2mtd_dev *add_device(
+ dev->mtd.read = block2mtd_read;
+ dev->mtd.priv = dev;
+ dev->mtd.owner = THIS_MODULE;
++ dev->mtd.refresh_device = block2mtd_refresh;
+
+ part = kzalloc(sizeof(struct mtd_partition), GFP_KERNEL);
+ part->name = dev->mtd.name;
projects / openwrt.git / blobdiff