s390/crypto: simplify return code handling

The CPACF instructions can complete with three different condition codes:
CC=0 for successful completion, CC=1 if the protected key verification
failed, and CC=3 for partial completion.

The inline functions will restart the CPACF instruction for partial
completion, this removes the CC=3 case. The CC=1 case is only relevant
for the protected key functions of the KM, KMC, KMAC and KMCTR
instructions. As the protected key functions are not used by the
current code, there is no need for any kind of return code handling.

Reviewed-by: Harald Freudenberger <freude@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 8 insertions, 25 deletions

diff --git a/arch/s390/include/asm/cpacf.h b/arch/s390/include/asm/cpacf.h
index ca884198805c..c226c9ba24ac 100644
--- a/arch/s390/include/asm/cpacf.h
+++ b/arch/s390/include/asm/cpacf.h
@@ -234,11 +234,9 @@ static inline int cpacf_kmc(unsigned long func, void *param,
  * @param: address of parameter block; see POP for details on each func
  * @src: address of source memory area
  * @src_len: length of src operand in bytes
- *
- * Returns 0 for the query func, number of processed bytes for digest funcs
  */
-static inline int cpacf_kimd(unsigned long func, void *param,
-			     const u8 *src, long src_len)
+static inline void cpacf_kimd(unsigned long func, void *param,
+			      const u8 *src, long src_len)
 {
 	register unsigned long r0 asm("0") = (unsigned long) func;
 	register unsigned long r1 asm("1") = (unsigned long) param;
@@ -251,8 +249,6 @@ static inline int cpacf_kimd(unsigned long func, void *param,
 		: [src] "+a" (r2), [len] "+d" (r3)
 		: [fc] "d" (r0), [pba] "a" (r1), [opc] "i" (CPACF_KIMD)
 		: "cc", "memory");
-
-	return src_len - r3;
 }
 
 /**
@@ -261,11 +257,9 @@ static inline int cpacf_kimd(unsigned long func, void *param,
  * @param: address of parameter block; see POP for details on each func
  * @src: address of source memory area
  * @src_len: length of src operand in bytes
- *
- * Returns 0 for the query func, number of processed bytes for digest funcs
  */
-static inline int cpacf_klmd(unsigned long func, void *param,
-			     const u8 *src, long src_len)
+static inline void cpacf_klmd(unsigned long func, void *param,
+			      const u8 *src, long src_len)
 {
 	register unsigned long r0 asm("0") = (unsigned long) func;
 	register unsigned long r1 asm("1") = (unsigned long) param;
@@ -278,8 +272,6 @@ static inline int cpacf_klmd(unsigned long func, void *param,
 		: [src] "+a" (r2), [len] "+d" (r3)
 		: [fc] "d" (r0), [pba] "a" (r1), [opc] "i" (CPACF_KLMD)
 		: "cc", "memory");
-
-	return src_len - r3;
 }
 
 /**
@@ -352,13 +344,10 @@ static inline int cpacf_kmctr(unsigned long func, void *param, u8 *dest,
  * @dest_len: size of destination memory area in bytes
  * @seed: address of seed data
  * @seed_len: size of seed data in bytes
- *
- * Returns 0 for the query func, number of random bytes stored in
- * dest buffer for generate function
  */
-static inline int cpacf_ppno(unsigned long func, void *param,
-			     u8 *dest, long dest_len,
-			     const u8 *seed, long seed_len)
+static inline void cpacf_ppno(unsigned long func, void *param,
+			      u8 *dest, long dest_len,
+			      const u8 *seed, long seed_len)
 {
 	register unsigned long r0 asm("0") = (unsigned long) func;
 	register unsigned long r1 asm("1") = (unsigned long) param;
@@ -374,8 +363,6 @@ static inline int cpacf_ppno(unsigned long func, void *param,
 		: [fc] "d" (r0), [pba] "a" (r1),
 		  [seed] "a" (r4), [slen] "d" (r5), [opc] "i" (CPACF_PPNO)
 		: "cc", "memory");
-
-	return dest_len - r3;
 }
 
 /**
@@ -383,10 +370,8 @@ static inline int cpacf_ppno(unsigned long func, void *param,
  *		 instruction
  * @func: the function code passed to PCC; see CPACF_KM_xxx defines
  * @param: address of parameter block; see POP for details on each func
- *
- * Returns 0.
  */
-static inline int cpacf_pcc(unsigned long func, void *param)
+static inline void cpacf_pcc(unsigned long func, void *param)
 {
 	register unsigned long r0 asm("0") = (unsigned long) func;
 	register unsigned long r1 asm("1") = (unsigned long) param;
@@ -397,8 +382,6 @@ static inline int cpacf_pcc(unsigned long func, void *param)
 		:
 		: [fc] "d" (r0), [pba] "a" (r1), [opc] "i" (CPACF_PCC)
 		: "cc", "memory");
-
-	return 0;
 }
 
 #endif	/* _ASM_S390_CPACF_H */