--- 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;