zram: support compaction

[karo-tx-linux.git] / drivers / block / zram / zram_drv.c

diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index 871bd3550cb0e0842296771412e749225542ffac..1626961fdb2f1306b1c47d7e7cd88a3df3ab3b57 100644 (file)
--- a/drivers/block/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -63,6 +63,27 @@ static inline struct zram *dev_to_zram(struct device *dev)
        return (struct zram *)dev_to_disk(dev)->private_data;
 }
 
+static ssize_t compact_store(struct device *dev,
+               struct device_attribute *attr, const char *buf, size_t len)
+{
+       unsigned long nr_migrated;
+       struct zram *zram = dev_to_zram(dev);
+       struct zram_meta *meta;
+
+       down_read(&zram->init_lock);
+       if (!init_done(zram)) {
+               up_read(&zram->init_lock);
+               return -EINVAL;
+       }
+
+       meta = zram->meta;
+       nr_migrated = zs_compact(meta->mem_pool);
+       atomic64_add(nr_migrated, &zram->stats.num_migrated);
+       up_read(&zram->init_lock);
+
+       return len;
+}
+
 static ssize_t disksize_show(struct device *dev,
                struct device_attribute *attr, char *buf)
 {
@@ -1017,6 +1038,7 @@ static const struct block_device_operations zram_devops = {
        .owner = THIS_MODULE
 };
 
+static DEVICE_ATTR_WO(compact);
 static DEVICE_ATTR_RW(disksize);
 static DEVICE_ATTR_RO(initstate);
 static DEVICE_ATTR_WO(reset);
@@ -1035,6 +1057,7 @@ ZRAM_ATTR_RO(invalid_io);
 ZRAM_ATTR_RO(notify_free);
 ZRAM_ATTR_RO(zero_pages);
 ZRAM_ATTR_RO(compr_data_size);
+ZRAM_ATTR_RO(num_migrated);
 
 static struct attribute *zram_disk_attrs[] = {
        &dev_attr_disksize.attr,
@@ -1044,6 +1067,8 @@ static struct attribute *zram_disk_attrs[] = {
        &dev_attr_num_writes.attr,
        &dev_attr_failed_reads.attr,
        &dev_attr_failed_writes.attr,
+       &dev_attr_num_migrated.attr,
+       &dev_attr_compact.attr,
        &dev_attr_invalid_io.attr,
        &dev_attr_notify_free.attr,
        &dev_attr_zero_pages.attr,