From 803521b149c8c71a712445a32bd9316e074df76a Mon Sep 17 00:00:00 2001
From: Mikhail Zaslonko <zaslonko@linux.ibm.com>
Date: Thu, 30 Jan 2020 22:16:30 -0800
Subject: lib/zlib: add zlib_deflate_dfltcc_enabled() function

Add a new function to zlib.h checking if s390 Deflate-Conversion
facility is installed and enabled.

Link: http://lkml.kernel.org/r/20200103223334.20669-6-zaslonko@linux.ibm.com
Signed-off-by: Mikhail Zaslonko <zaslonko@linux.ibm.com>
Cc: Chris Mason <clm@fb.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: David Sterba <dsterba@suse.com>
Cc: Eduard Shishkin <edward6@linux.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ilya Leoshkevich <iii@linux.ibm.com>
Cc: Josef Bacik <josef@toxicpanda.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
 lib/zlib_dfltcc/dfltcc.h | 11 +++++++++++
 1 file changed, 11 insertions(+)

(limited to 'lib/zlib_dfltcc/dfltcc.h')

diff --git a/lib/zlib_dfltcc/dfltcc.h b/lib/zlib_dfltcc/dfltcc.h
index be70c807b62f..2a2fac1d050a 100644
--- a/lib/zlib_dfltcc/dfltcc.h
+++ b/lib/zlib_dfltcc/dfltcc.h
@@ -3,6 +3,8 @@
 #define DFLTCC_H
 
 #include "../zlib_deflate/defutil.h"
+#include <asm/facility.h>
+#include <asm/setup.h>
 
 /*
  * Tuning parameters.
@@ -14,6 +16,8 @@
 #define DFLTCC_DHT_MIN_SAMPLE_SIZE 4096
 #define DFLTCC_RIBM 0
 
+#define DFLTCC_FACILITY 151
+
 /*
  * Parameter Block for Query Available Functions.
  */
@@ -113,6 +117,11 @@ typedef enum {
 } dfltcc_inflate_action;
 dfltcc_inflate_action dfltcc_inflate(z_streamp strm,
                                      int flush, int *ret);
+static inline int is_dfltcc_enabled(void)
+{
+return (zlib_dfltcc_support != ZLIB_DFLTCC_DISABLED &&
+        test_facility(DFLTCC_FACILITY));
+}
 
 #define DEFLATE_RESET_HOOK(strm) \
     dfltcc_reset((strm), sizeof(deflate_state))
@@ -121,6 +130,8 @@ dfltcc_inflate_action dfltcc_inflate(z_streamp strm,
 
 #define DEFLATE_NEED_CHECKSUM(strm) (!dfltcc_can_deflate((strm)))
 
+#define DEFLATE_DFLTCC_ENABLED() is_dfltcc_enabled()
+
 #define INFLATE_RESET_HOOK(strm) \
     dfltcc_reset((strm), sizeof(struct inflate_state))
 
-- 
cgit v1.2.3