[dm-devel] [PATCH 4/6] libmpathpersist: fix byte swapping for big endian systems

[Martin Wilck]

This code was obviously intended to convert big-endian data
from PRIN to CPU endianness. It doesn't work on big endian systems.

Signed-off-by: Martin Wilck <mwilck at suse.com>
---
 libmpathpersist/mpath_persist.c  |  7 +------
 libmpathpersist/mpath_pr_ioctl.c | 16 ++--------------
 2 files changed, 3 insertions(+), 20 deletions(-)

diff --git a/libmpathpersist/mpath_persist.c b/libmpathpersist/mpath_persist.c
index 907a17c9..12dad7a7 100644
--- a/libmpathpersist/mpath_persist.c
+++ b/libmpathpersist/mpath_persist.c
@@ -543,12 +543,7 @@ int mpath_prout_reg(struct multipath *mpp,int rq_servact, int rq_scope,
 		}
 		if (!rollback && (thread[i].param.status == MPATH_PR_RESERV_CONFLICT)){
 			rollback = 1;
-			sa_key = 0;
-			for (i = 0; i < 8; ++i){
-				if (i > 0)
-					sa_key <<= 8;
-				sa_key |= paramp->sa_key[i];
-			}
+			sa_key = be64_to_cpu(*(uint64_t *)&paramp->sa_key[0]);
 			status = MPATH_PR_RESERV_CONFLICT ;
 		}
 		if (!rollback && (status == MPATH_PR_SUCCESS)){
diff --git a/libmpathpersist/mpath_pr_ioctl.c b/libmpathpersist/mpath_pr_ioctl.c
index 347f21b2..76271ff1 100644
--- a/libmpathpersist/mpath_pr_ioctl.c
+++ b/libmpathpersist/mpath_pr_ioctl.c
@@ -485,24 +485,12 @@ int mpath_isLittleEndian(void)
 
 void mpath_reverse_uint16_byteorder(uint16_t *num)
 {
-	uint16_t byte0, byte1;
-
-	byte0 = (*num & 0x000000FF) >>  0 ;
-	byte1 = (*num & 0x0000FF00) >>  8 ;
-
-	*num = ((byte0 << 8) | (byte1 << 0));
+	*num = get_unaligned_be16(num);
 }
 
 void mpath_reverse_uint32_byteorder(uint32_t *num)
 {
-	uint32_t byte0, byte1, byte2, byte3;
-
-	byte0 = (*num & 0x000000FF) >>  0 ;
-	byte1 = (*num & 0x0000FF00) >>  8 ;
-	byte2 = (*num & 0x00FF0000) >> 16 ;
-	byte3 = (*num & 0xFF000000) >> 24 ;
-
-	*num = ((byte0 << 24) | (byte1 << 16) | (byte2 << 8) | (byte3 << 0));
+	*num = get_unaligned_be32(num);
 }
 
 void
-- 
2.17.1