s390/cpufeature: rework to allow more than only hwcap bits

Rework cpufeature implementation to allow for various cpu feature
indications, which is not only limited to hwcap bits. This is achieved
by adding a sequential list of cpu feature numbers, where each of them
is mapped to an entry which indicates what this number is about.

Each entry contains a type member, which indicates what feature
name space to look into (e.g. hwcap, or cpu facility). If wanted this
allows also to automatically load modules only in e.g. z/VM
configurations.

Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Steffen Eiden <seiden@linux.ibm.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Reviewed-by: Hendrik Brueckner <brueckner@linux.ibm.com>
Link: https://lore.kernel.org/r/20220713125644.16121-2-seiden@linux.ibm.com
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>

diff --git a/arch/s390/crypto/aes_s390.c b/arch/s390/crypto/aes_s390.c
index 1023e9d..526c3f4 100644 (file)
--- a/arch/s390/crypto/aes_s390.c
+++ b/arch/s390/crypto/aes_s390.c
@@ -1049,7 +1049,7 @@ out_err:
        return ret;
 }
 
-module_cpu_feature_match(MSA, aes_s390_init);
+module_cpu_feature_match(S390_CPU_FEATURE_MSA, aes_s390_init);
 module_exit(aes_s390_fini);
 
 MODULE_ALIAS_CRYPTO("aes-all");

diff --git a/arch/s390/crypto/chacha-glue.c b/arch/s390/crypto/chacha-glue.c
index 2ec51f3..7752bd3 100644 (file)
--- a/arch/s390/crypto/chacha-glue.c
+++ b/arch/s390/crypto/chacha-glue.c
@@ -121,7 +121,7 @@ static void __exit chacha_mod_fini(void)
                crypto_unregister_skciphers(chacha_algs, ARRAY_SIZE(chacha_algs));
 }
 
-module_cpu_feature_match(VXRS, chacha_mod_init);
+module_cpu_feature_match(S390_CPU_FEATURE_VXRS, chacha_mod_init);
 module_exit(chacha_mod_fini);
 
 MODULE_DESCRIPTION("ChaCha20 stream cipher");

diff --git a/arch/s390/crypto/crc32-vx.c b/arch/s390/crypto/crc32-vx.c
index fafecad..017143e 100644 (file)
--- a/arch/s390/crypto/crc32-vx.c
+++ b/arch/s390/crypto/crc32-vx.c
@@ -298,7 +298,7 @@ static void __exit crc_vx_mod_exit(void)
        crypto_unregister_shashes(crc32_vx_algs, ARRAY_SIZE(crc32_vx_algs));
 }
 
-module_cpu_feature_match(VXRS, crc_vx_mod_init);
+module_cpu_feature_match(S390_CPU_FEATURE_VXRS, crc_vx_mod_init);
 module_exit(crc_vx_mod_exit);
 
 MODULE_AUTHOR("Hendrik Brueckner <brueckner@linux.vnet.ibm.com>");

diff --git a/arch/s390/crypto/des_s390.c b/arch/s390/crypto/des_s390.c
index e013088..8e75b83 100644 (file)
--- a/arch/s390/crypto/des_s390.c
+++ b/arch/s390/crypto/des_s390.c
@@ -492,7 +492,7 @@ out_err:
        return ret;
 }
 
-module_cpu_feature_match(MSA, des_s390_init);
+module_cpu_feature_match(S390_CPU_FEATURE_MSA, des_s390_init);
 module_exit(des_s390_exit);
 
 MODULE_ALIAS_CRYPTO("des");

diff --git a/arch/s390/crypto/ghash_s390.c b/arch/s390/crypto/ghash_s390.c
index 6b07a2f..0800a2a 100644 (file)
--- a/arch/s390/crypto/ghash_s390.c
+++ b/arch/s390/crypto/ghash_s390.c
@@ -145,7 +145,7 @@ static void __exit ghash_mod_exit(void)
        crypto_unregister_shash(&ghash_alg);
 }
 
-module_cpu_feature_match(MSA, ghash_mod_init);
+module_cpu_feature_match(S390_CPU_FEATURE_MSA, ghash_mod_init);
 module_exit(ghash_mod_exit);
 
 MODULE_ALIAS_CRYPTO("ghash");

diff --git a/arch/s390/crypto/prng.c b/arch/s390/crypto/prng.c
index ae382ba..a077087 100644 (file)
--- a/arch/s390/crypto/prng.c
+++ b/arch/s390/crypto/prng.c
@@ -907,5 +907,5 @@ static void __exit prng_exit(void)
        }
 }
 
-module_cpu_feature_match(MSA, prng_init);
+module_cpu_feature_match(S390_CPU_FEATURE_MSA, prng_init);
 module_exit(prng_exit);

diff --git a/arch/s390/crypto/sha1_s390.c b/arch/s390/crypto/sha1_s390.c
index a3fabf3..bc3a227 100644 (file)
--- a/arch/s390/crypto/sha1_s390.c
+++ b/arch/s390/crypto/sha1_s390.c
@@ -95,7 +95,7 @@ static void __exit sha1_s390_fini(void)
        crypto_unregister_shash(&alg);
 }
 
-module_cpu_feature_match(MSA, sha1_s390_init);
+module_cpu_feature_match(S390_CPU_FEATURE_MSA, sha1_s390_init);
 module_exit(sha1_s390_fini);
 
 MODULE_ALIAS_CRYPTO("sha1");

diff --git a/arch/s390/crypto/sha256_s390.c b/arch/s390/crypto/sha256_s390.c
index 24983f1..6f1ccdf 100644 (file)
--- a/arch/s390/crypto/sha256_s390.c
+++ b/arch/s390/crypto/sha256_s390.c
@@ -134,7 +134,7 @@ static void __exit sha256_s390_fini(void)
        crypto_unregister_shash(&sha256_alg);
 }
 
-module_cpu_feature_match(MSA, sha256_s390_init);
+module_cpu_feature_match(S390_CPU_FEATURE_MSA, sha256_s390_init);
 module_exit(sha256_s390_fini);
 
 MODULE_ALIAS_CRYPTO("sha256");

diff --git a/arch/s390/crypto/sha3_256_s390.c b/arch/s390/crypto/sha3_256_s390.c
index 30ac49b..e1350e0 100644 (file)
--- a/arch/s390/crypto/sha3_256_s390.c
+++ b/arch/s390/crypto/sha3_256_s390.c
@@ -137,7 +137,7 @@ static void __exit sha3_256_s390_fini(void)
        crypto_unregister_shash(&sha3_256_alg);
 }
 
-module_cpu_feature_match(MSA, sha3_256_s390_init);
+module_cpu_feature_match(S390_CPU_FEATURE_MSA, sha3_256_s390_init);
 module_exit(sha3_256_s390_fini);
 
 MODULE_ALIAS_CRYPTO("sha3-256");

diff --git a/arch/s390/crypto/sha3_512_s390.c b/arch/s390/crypto/sha3_512_s390.c
index e70d50f..06c142e 100644 (file)
--- a/arch/s390/crypto/sha3_512_s390.c
+++ b/arch/s390/crypto/sha3_512_s390.c
@@ -147,7 +147,7 @@ static void __exit fini(void)
        crypto_unregister_shash(&sha3_384_alg);
 }
 
-module_cpu_feature_match(MSA, init);
+module_cpu_feature_match(S390_CPU_FEATURE_MSA, init);
 module_exit(fini);
 
 MODULE_LICENSE("GPL");

diff --git a/arch/s390/crypto/sha512_s390.c b/arch/s390/crypto/sha512_s390.c
index 43ce495..04f11c4 100644 (file)
--- a/arch/s390/crypto/sha512_s390.c
+++ b/arch/s390/crypto/sha512_s390.c
@@ -142,7 +142,7 @@ static void __exit fini(void)
        crypto_unregister_shash(&sha384_alg);
 }
 
-module_cpu_feature_match(MSA, init);
+module_cpu_feature_match(S390_CPU_FEATURE_MSA, init);
 module_exit(fini);
 
 MODULE_LICENSE("GPL");

diff --git a/arch/s390/include/asm/cpufeature.h b/arch/s390/include/asm/cpufeature.h
index 14cfd48..771caf5 100644 (file)
--- a/arch/s390/include/asm/cpufeature.h
+++ b/arch/s390/include/asm/cpufeature.h
@@ -2,28 +2,20 @@
 /*
  * Module interface for CPU features
  *
- * Copyright IBM Corp. 2015
+ * Copyright IBM Corp. 2015, 2022
  * Author(s): Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
  */
 
 #ifndef __ASM_S390_CPUFEATURE_H
 #define __ASM_S390_CPUFEATURE_H
 
-#include <asm/elf.h>
+enum {
+       S390_CPU_FEATURE_MSA,
+       S390_CPU_FEATURE_VXRS,
+       MAX_CPU_FEATURES
+};
 
-/* Hardware features on Linux on z Systems are indicated by facility bits that
- * are mapped to the so-called machine flags.  Particular machine flags are
- * then used to define ELF hardware capabilities; most notably hardware flags
- * that are essential for user space / glibc.
- *
- * Restrict the set of exposed CPU features to ELF hardware capabilities for
- * now.  Additional machine flags can be indicated by values larger than
- * MAX_ELF_HWCAP_FEATURES.
- */
-#define MAX_ELF_HWCAP_FEATURES (8 * sizeof(elf_hwcap))
-#define MAX_CPU_FEATURES       MAX_ELF_HWCAP_FEATURES
-
-#define cpu_feature(feat)      ilog2(HWCAP_ ## feat)
+#define cpu_feature(feature)   (feature)
 
 int cpu_have_feature(unsigned int nr);
 

diff --git a/arch/s390/kernel/Makefile b/arch/s390/kernel/Makefile
index 27d6b3c..3cbfa9f 100644 (file)
--- a/arch/s390/kernel/Makefile
+++ b/arch/s390/kernel/Makefile
@@ -35,7 +35,7 @@ CFLAGS_unwind_bc.o    += -fno-optimize-sibling-calls
 
 obj-y  := traps.o time.o process.o earlypgm.o early.o setup.o idle.o vtime.o
 obj-y  += processor.o syscall.o ptrace.o signal.o cpcmd.o ebcdic.o nmi.o
-obj-y  += debug.o irq.o ipl.o dis.o diag.o vdso.o
+obj-y  += debug.o irq.o ipl.o dis.o diag.o vdso.o cpufeature.o
 obj-y  += sysinfo.o lgr.o os_info.o machine_kexec.o
 obj-y  += runtime_instr.o cache.o fpu.o dumpstack.o guarded_storage.o sthyi.o
 obj-y  += entry.o reipl.o relocate_kernel.o kdebugfs.o alternative.o

diff --git a/arch/s390/kernel/cpufeature.c b/arch/s390/kernel/cpufeature.c
new file mode 100644 (file)
index 0000000..89c4183
--- /dev/null
+++ b/arch/s390/kernel/cpufeature.c
@@ -0,0 +1,42 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright IBM Corp. 2022
+ */
+
+#include <linux/cpufeature.h>
+#include <linux/bug.h>
+#include <asm/elf.h>
+
+enum {
+       TYPE_HWCAP,
+};
+
+struct s390_cpu_feature {
+       unsigned int type       : 4;
+       unsigned int num        : 28;
+};
+
+static struct s390_cpu_feature s390_cpu_features[MAX_CPU_FEATURES] = {
+       [S390_CPU_FEATURE_MSA]  = {.type = TYPE_HWCAP, .num = HWCAP_NR_MSA},
+       [S390_CPU_FEATURE_VXRS] = {.type = TYPE_HWCAP, .num = HWCAP_NR_VXRS},
+};
+
+/*
+ * cpu_have_feature - Test CPU features on module initialization
+ */
+int cpu_have_feature(unsigned int num)
+{
+       struct s390_cpu_feature *feature;
+
+       if (WARN_ON_ONCE(num >= MAX_CPU_FEATURES))
+               return 0;
+       feature = &s390_cpu_features[num];
+       switch (feature->type) {
+       case TYPE_HWCAP:
+               return !!(elf_hwcap & BIT(feature->num));
+       default:
+               WARN_ON_ONCE(1);
+               return 0;
+       }
+}
+EXPORT_SYMBOL(cpu_have_feature);

diff --git a/arch/s390/kernel/processor.c b/arch/s390/kernel/processor.c
index aa0e0e7..a194611 100644 (file)
--- a/arch/s390/kernel/processor.c
+++ b/arch/s390/kernel/processor.c
@@ -8,7 +8,6 @@
 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
 
 #include <linux/stop_machine.h>
-#include <linux/cpufeature.h>
 #include <linux/bitops.h>
 #include <linux/kernel.h>
 #include <linux/random.h>
@@ -96,15 +95,6 @@ void cpu_init(void)
        enter_lazy_tlb(&init_mm, current);
 }
 
-/*
- * cpu_have_feature - Test CPU features on module initialization
- */
-int cpu_have_feature(unsigned int num)
-{
-       return elf_hwcap & (1UL << num);
-}
-EXPORT_SYMBOL(cpu_have_feature);
-
 static void show_facilities(struct seq_file *m)
 {
        unsigned int bit;

diff --git a/drivers/char/hw_random/s390-trng.c b/drivers/char/hw_random/s390-trng.c
index 2beaa35..12fbac0 100644 (file)
--- a/drivers/char/hw_random/s390-trng.c
+++ b/drivers/char/hw_random/s390-trng.c
@@ -261,5 +261,5 @@ static void __exit trng_exit(void)
        trng_debug_exit();
 }
 
-module_cpu_feature_match(MSA, trng_init);
+module_cpu_feature_match(S390_CPU_FEATURE_MSA, trng_init);
 module_exit(trng_exit);

diff --git a/drivers/s390/crypto/pkey_api.c b/drivers/s390/crypto/pkey_api.c
index 7329caa..5a05d1c 100644 (file)
--- a/drivers/s390/crypto/pkey_api.c
+++ b/drivers/s390/crypto/pkey_api.c
@@ -2115,5 +2115,5 @@ static void __exit pkey_exit(void)
        pkey_debug_exit();
 }
 
-module_cpu_feature_match(MSA, pkey_init);
+module_cpu_feature_match(S390_CPU_FEATURE_MSA, pkey_init);
 module_exit(pkey_exit);