1 files changed, 20 insertions, 4 deletions

diff --git a/Documentation/blockdev/zram.txt b/Documentation/blockdev/zram.txt
index 0595c3f56ccf..82c6a41116db 100644
--- a/Documentation/blockdev/zram.txt
+++ b/Documentation/blockdev/zram.txt
@@ -74,14 +74,30 @@ There is little point creating a zram of greater than twice the size of memory
 since we expect a 2:1 compression ratio. Note that zram uses about 0.1% of the
 size of the disk when not in use so a huge zram is wasteful.
 
-5) Activate:
+5) Set memory limit: Optional
+        Set memory limit by writing the value to sysfs node 'mem_limit'.
+        The value can be either in bytes or you can use mem suffixes.
+        In addition, you could change the value in runtime.
+        Examples:
+            # limit /dev/zram0 with 50MB memory
+            echo $((50*1024*1024)) > /sys/block/zram0/mem_limit
+
+            # Using mem suffixes
+            echo 256K > /sys/block/zram0/mem_limit
+            echo 512M > /sys/block/zram0/mem_limit
+            echo 1G > /sys/block/zram0/mem_limit
+
+            # To disable memory limit
+            echo 0 > /sys/block/zram0/mem_limit
+
+6) Activate:
         mkswap /dev/zram0
         swapon /dev/zram0
 
         mkfs.ext4 /dev/zram1
         mount /dev/zram1 /tmp
 
-6) Stats:
+7) Stats:
         Per-device statistics are exported as various nodes under
         /sys/block/zram<id>/
                 disksize
@@ -96,11 +112,11 @@ size of the disk when not in use so a huge zram is wasteful.
                 compr_data_size
                 mem_used_total
 
-7) Deactivate:
+8) Deactivate:
         swapoff /dev/zram0
         umount /dev/zram1
 
-8) Reset:
+9) Reset:
         Write any positive value to 'reset' sysfs node
         echo 1 > /sys/block/zram0/reset
         echo 1 > /sys/block/zram1/reset