--- zzzz-none-000/linux-2.6.32.61/drivers/mtd/devices/block2mtd.c 2013-06-10 09:43:48.000000000 +0000 +++ ar9-7330-650/linux-2.6.32.61/drivers/mtd/devices/block2mtd.c 2011-07-20 07:23:51.000000000 +0000 @@ -14,6 +14,7 @@ #include #include #include +#include #include #include #include @@ -28,6 +29,8 @@ struct block_device *blkdev; struct mtd_info mtd; struct mutex write_mutex; + rwlock_t bdev_mutex; + char devname[0]; }; @@ -80,6 +83,12 @@ 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); @@ -92,6 +101,10 @@ instr->state = MTD_ERASE_DONE; mtd_erase_callback(instr); + +done: + read_unlock(&dev->bdev_mutex); + return err; } @@ -103,10 +116,14 @@ 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; @@ -121,10 +138,14 @@ 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); @@ -135,7 +156,10 @@ offset = 0; index++; } - return 0; + +done: + read_unlock(&dev->bdev_mutex); + return err; } @@ -187,12 +211,22 @@ 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; @@ -201,6 +235,9 @@ mutex_unlock(&dev->write_mutex); if (err > 0) err = 0; + +done: + read_unlock(&dev->bdev_mutex); return err; } @@ -209,51 +246,30 @@ 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) +static int _open_bdev(struct block2mtd_dev *dev) { struct block_device *bdev; - struct block2mtd_dev *dev; - 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)) { + dev_t devt = name_to_dev_t(dev->devname); /* 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); + wait_for_device_probe(); if (devt) { bdev = open_by_devnum(devt, FMODE_WRITE | FMODE_READ); } @@ -261,29 +277,110 @@ #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); + + if (!mtdname) + mtdname = devname; - /* Setup the MTD structure */ - /* make the name contain the block device in */ - name = kmalloc(sizeof("block2mtd: ") + strlen(devname) + 1, - GFP_KERNEL); + name = kmalloc(strlen(mtdname) + 1, GFP_KERNEL); if (!name) goto devinit_err; - sprintf(name, "block2mtd: %s", devname); + strcpy(name, mtdname); dev->mtd.name = name; - dev->mtd.size = dev->blkdev->bd_inode->i_size & PAGE_MASK; + dev->mtd.size = dev->blkdev->bd_inode->i_size & PAGE_MASK & ~(erase_size - 1); dev->mtd.erasesize = erase_size; dev->mtd.writesize = 1; dev->mtd.type = MTD_RAM; @@ -295,15 +392,19 @@ dev->mtd.read = block2mtd_read; dev->mtd.priv = dev; dev->mtd.owner = THIS_MODULE; + dev->mtd.refresh_device = block2mtd_refresh; - if (add_mtd_device(&dev->mtd)) { + part = kzalloc(sizeof(struct mtd_partition), GFP_KERNEL); + part->name = dev->mtd.name; + part->offset = 0; + part->size = dev->mtd.size; + if (add_mtd_partitions(&dev->mtd, part, 1)) { /* Device didnt get added, so free the entry */ goto devinit_err; } list_add(&dev->list, &blkmtd_device_list); INFO("mtd%d: [%s] erase_size = %dKiB [%d]", dev->mtd.index, - dev->mtd.name + strlen("block2mtd: "), - dev->mtd.erasesize >> 10, dev->mtd.erasesize); + mtdname, dev->mtd.erasesize >> 10, dev->mtd.erasesize); return dev; devinit_err: @@ -376,9 +477,9 @@ static int block2mtd_setup2(const char *val) { - char buf[80 + 12]; /* 80 for device, 12 for erase size */ + char buf[80 + 12 + 80]; /* 80 for device, 12 for erase size, 80 for name */ char *str = buf; - char *token[2]; + char *token[3]; char *name; size_t erase_size = PAGE_SIZE; int i, ret; @@ -389,7 +490,7 @@ strcpy(str, val); kill_final_newline(str); - for (i = 0; i < 2; i++) + for (i = 0; i < 3; i++) token[i] = strsep(&str, ","); if (str) @@ -408,8 +509,10 @@ parse_err("illegal erase size"); } } + if (token[2] && (strlen(token[2]) + 1 > 80)) + parse_err("mtd device name too long"); - add_device(name, erase_size); + add_device(name, erase_size, token[2]); return 0; } @@ -443,7 +546,7 @@ module_param_call(block2mtd, block2mtd_setup, NULL, NULL, 0200); -MODULE_PARM_DESC(block2mtd, "Device to use. \"block2mtd=[,]\""); +MODULE_PARM_DESC(block2mtd, "Device to use. \"block2mtd=[,[,]]\""); static int __init block2mtd_init(void) {