diff options
| -rw-r--r-- | drivers/block/zram/zram_drv.c | 53 | ||||
| -rw-r--r-- | drivers/block/zram/zram_drv.h | 4 |
2 files changed, 38 insertions, 19 deletions
diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c index a52a8191bb91..6a3b36d5bad6 100644 --- a/drivers/block/zram/zram_drv.c +++ b/drivers/block/zram/zram_drv.c @@ -1070,45 +1070,60 @@ static ssize_t reset_store(struct device *dev, struct zram *zram; struct block_device *bdev; + ret = kstrtou16(buf, 10, &do_reset); + if (ret) + return ret; + + if (!do_reset) + return -EINVAL; + zram = dev_to_zram(dev); bdev = bdget_disk(zram->disk, 0); - if (!bdev) return -ENOMEM; mutex_lock(&bdev->bd_mutex); - /* Do not reset an active device! */ - if (bdev->bd_openers) { - ret = -EBUSY; - goto out; + /* Do not reset an active device or claimed device */ + if (bdev->bd_openers || zram->claim) { + mutex_unlock(&bdev->bd_mutex); + bdput(bdev); + return -EBUSY; } - ret = kstrtou16(buf, 10, &do_reset); - if (ret) - goto out; - - if (!do_reset) { - ret = -EINVAL; - goto out; - } + /* From now on, anyone can't open /dev/zram[0-9] */ + zram->claim = true; + mutex_unlock(&bdev->bd_mutex); - /* Make sure all pending I/O is finished */ + /* Make sure all the pending I/O are finished */ fsync_bdev(bdev); zram_reset_device(zram); - - mutex_unlock(&bdev->bd_mutex); revalidate_disk(zram->disk); bdput(bdev); + mutex_lock(&bdev->bd_mutex); + zram->claim = false; + mutex_unlock(&bdev->bd_mutex); + return len; +} + +static int zram_open(struct block_device *bdev, fmode_t mode) +{ + int ret = 0; + struct zram *zram; + + WARN_ON(!mutex_is_locked(&bdev->bd_mutex)); + + zram = bdev->bd_disk->private_data; + /* zram was claimed to reset so open request fails */ + if (zram->claim) + ret = -EBUSY; -out: - mutex_unlock(&bdev->bd_mutex); - bdput(bdev); return ret; } static const struct block_device_operations zram_devops = { + .open = zram_open, .swap_slot_free_notify = zram_slot_free_notify, .rw_page = zram_rw_page, .owner = THIS_MODULE diff --git a/drivers/block/zram/zram_drv.h b/drivers/block/zram/zram_drv.h index 042994e807cf..6dbe2df506bf 100644 --- a/drivers/block/zram/zram_drv.h +++ b/drivers/block/zram/zram_drv.h @@ -115,5 +115,9 @@ struct zram { */ u64 disksize; /* bytes */ char compressor[10]; + /* + * zram is claimed so open request will be failed + */ + bool claim; /* Protected by bdev->bd_mutex */ }; #endif |