zram: document failed_reads, failed_writes stats

Document `failed_reads' and `failed_writes' device attributes.
Remove info about `discard' - there is no such zram attr.

Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Jerome Marchand <jmarchan@redhat.com>
Cc: Nitin Gupta <ngupta@vflare.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 2 insertions, 1 deletions

diff --git a/Documentation/blockdev/zram.txt b/Documentation/blockdev/zram.txt
index 393541be1ec0..b31ac5e5d4b9 100644
--- a/Documentation/blockdev/zram.txt
+++ b/Documentation/blockdev/zram.txt
@@ -51,9 +51,10 @@ size of the disk when not in use so a huge zram is wasteful.
                 disksize
                 num_reads
                 num_writes
+                failed_reads
+                failed_writes
                 invalid_io
                 notify_free
-                discard
                 zero_pages
                 orig_data_size
                 compr_data_size