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Diffstat (limited to 'arch/s390/include/asm/pai.h')
-rw-r--r--arch/s390/include/asm/pai.h74
1 files changed, 74 insertions, 0 deletions
diff --git a/arch/s390/include/asm/pai.h b/arch/s390/include/asm/pai.h
new file mode 100644
index 000000000000..5b7e33ac6f0b
--- /dev/null
+++ b/arch/s390/include/asm/pai.h
@@ -0,0 +1,74 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Processor Activity Instrumentation support for cryptography counters
+ *
+ * Copyright IBM Corp. 2022
+ * Author(s): Thomas Richter <tmricht@linux.ibm.com>
+ */
+#ifndef _ASM_S390_PAI_H
+#define _ASM_S390_PAI_H
+
+#include <linux/jump_label.h>
+#include <asm/lowcore.h>
+#include <asm/ptrace.h>
+
+struct qpaci_info_block {
+ u64 header;
+ struct {
+ u64 : 8;
+ u64 num_cc : 8; /* # of supported crypto counters */
+ u64 : 48;
+ };
+};
+
+static inline int qpaci(struct qpaci_info_block *info)
+{
+ /* Size of info (in double words minus one) */
+ size_t size = sizeof(*info) / sizeof(u64) - 1;
+ int cc;
+
+ asm volatile(
+ " lgr 0,%[size]\n"
+ " .insn s,0xb28f0000,%[info]\n"
+ " lgr %[size],0\n"
+ " ipm %[cc]\n"
+ " srl %[cc],28\n"
+ : [cc] "=d" (cc), [info] "=Q" (*info), [size] "+&d" (size)
+ :
+ : "0", "cc", "memory");
+ return cc ? (size + 1) * sizeof(u64) : 0;
+}
+
+#define PAI_CRYPTO_BASE 0x1000 /* First event number */
+#define PAI_CRYPTO_MAXCTR 256 /* Max # of event counters */
+#define PAI_CRYPTO_KERNEL_OFFSET 2048
+
+DECLARE_STATIC_KEY_FALSE(pai_key);
+
+static __always_inline void pai_kernel_enter(struct pt_regs *regs)
+{
+ if (!IS_ENABLED(CONFIG_PERF_EVENTS))
+ return;
+ if (!static_branch_unlikely(&pai_key))
+ return;
+ if (!S390_lowcore.ccd)
+ return;
+ if (!user_mode(regs))
+ return;
+ WRITE_ONCE(S390_lowcore.ccd, S390_lowcore.ccd | PAI_CRYPTO_KERNEL_OFFSET);
+}
+
+static __always_inline void pai_kernel_exit(struct pt_regs *regs)
+{
+ if (!IS_ENABLED(CONFIG_PERF_EVENTS))
+ return;
+ if (!static_branch_unlikely(&pai_key))
+ return;
+ if (!S390_lowcore.ccd)
+ return;
+ if (!user_mode(regs))
+ return;
+ WRITE_ONCE(S390_lowcore.ccd, S390_lowcore.ccd & ~PAI_CRYPTO_KERNEL_OFFSET);
+}
+
+#endif