Merge tag 'csky-for-linus-5.7-rc1' of git://github.com/c-sky/csky-linux

Pull csky updates from Guo Ren:

 - Add kproobes/uprobes support

 - Add lockdep, rseq, gcov support

 - Fixup init_fpu

 - Fixup ftrace_modify deadlock

 - Fixup speculative execution on IO area

* tag 'csky-for-linus-5.7-rc1' of git://github.com/c-sky/csky-linux:
  csky: Fixup cpu speculative execution to IO area
  csky: Add uprobes support
  csky: Add kprobes supported
  csky: Enable LOCKDEP_SUPPORT
  csky: Enable the gcov function
  csky: Fixup get wrong psr value from phyical reg
  csky/ftrace: Fixup ftrace_modify_code deadlock without CPU_HAS_ICACHE_INS
  csky: Implement ftrace with regs
  csky: Add support for restartable sequence
  csky: Implement ptrace regs and stack API
  csky: Fixup init_fpu compile warning with __init

arch/csky/include/asm/ftrace.h

@@ -10,6 +10,8 @@
 
 #define HAVE_FUNCTION_GRAPH_RET_ADDR_PTR
 
+#define ARCH_SUPPORTS_FTRACE_OPS 1
+
 #define MCOUNT_ADDR	((unsigned long)_mcount)
 
 #ifndef __ASSEMBLY__

arch/csky/include/asm/kprobes.h

@@ -0,0 +1,48 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#ifndef __ASM_CSKY_KPROBES_H
+#define __ASM_CSKY_KPROBES_H
+
+#include <asm-generic/kprobes.h>
+
+#ifdef CONFIG_KPROBES
+#include <linux/types.h>
+#include <linux/ptrace.h>
+#include <linux/percpu.h>
+
+#define __ARCH_WANT_KPROBES_INSN_SLOT
+#define MAX_INSN_SIZE			1
+
+#define flush_insn_slot(p)		do { } while (0)
+#define kretprobe_blacklist_size	0
+
+#include <asm/probes.h>
+
+struct prev_kprobe {
+	struct kprobe *kp;
+	unsigned int status;
+};
+
+/* Single step context for kprobe */
+struct kprobe_step_ctx {
+	unsigned long ss_pending;
+	unsigned long match_addr;
+};
+
+/* per-cpu kprobe control block */
+struct kprobe_ctlblk {
+	unsigned int kprobe_status;
+	unsigned long saved_sr;
+	struct prev_kprobe prev_kprobe;
+	struct kprobe_step_ctx ss_ctx;
+};
+
+void arch_remove_kprobe(struct kprobe *p);
+int kprobe_fault_handler(struct pt_regs *regs, unsigned int trapnr);
+int kprobe_breakpoint_handler(struct pt_regs *regs);
+int kprobe_single_step_handler(struct pt_regs *regs);
+void kretprobe_trampoline(void);
+void __kprobes *trampoline_probe_handler(struct pt_regs *regs);
+
+#endif /* CONFIG_KPROBES */
+#endif /* __ASM_CSKY_KPROBES_H */

arch/csky/include/asm/probes.h

@@ -0,0 +1,24 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef __ASM_CSKY_PROBES_H
+#define __ASM_CSKY_PROBES_H
+
+typedef u32 probe_opcode_t;
+typedef void (probes_handler_t) (u32 opcode, long addr, struct pt_regs *);
+
+/* architecture specific copy of original instruction */
+struct arch_probe_insn {
+	probe_opcode_t *insn;
+	probes_handler_t *handler;
+	/* restore address after simulation */
+	unsigned long restore;
+};
+
+#ifdef CONFIG_KPROBES
+typedef u32 kprobe_opcode_t;
+struct arch_specific_insn {
+	struct arch_probe_insn api;
+};
+#endif
+
+#endif /* __ASM_CSKY_PROBES_H */

arch/csky/include/asm/processor.h

@@ -43,6 +43,7 @@ extern struct cpuinfo_csky cpu_data[];
 struct thread_struct {
 	unsigned long  ksp;       /* kernel stack pointer */
 	unsigned long  sr;        /* saved status register */
+	unsigned long  trap_no;   /* saved status register */
 
 	/* FPU regs */
 	struct user_fp __aligned(16) user_fp;

arch/csky/include/asm/ptrace.h

@@ -7,11 +7,14 @@
 #include <uapi/asm/ptrace.h>
 #include <asm/traps.h>
 #include <linux/types.h>
+#include <linux/compiler.h>
 
 #ifndef __ASSEMBLY__
 
 #define PS_S	0x80000000 /* Supervisor Mode */
 
+#define USR_BKPT	0x1464
+
 #define arch_has_single_step() (1)
 #define current_pt_regs() \
 ({ (struct pt_regs *)((char *)current_thread_info() + THREAD_SIZE) - 1; })
@@ -22,6 +25,18 @@
 #define instruction_pointer(regs) ((regs)->pc)
 #define profile_pc(regs) instruction_pointer(regs)
 
+static inline void instruction_pointer_set(struct pt_regs *regs,
+					   unsigned long val)
+{
+	regs->pc = val;
+}
+
+#if defined(__CSKYABIV2__)
+#define MAX_REG_OFFSET offsetof(struct pt_regs, dcsr)
+#else
+#define MAX_REG_OFFSET offsetof(struct pt_regs, regs[9])
+#endif
+
 static inline bool in_syscall(struct pt_regs const *regs)
 {
 	return ((regs->sr >> 16) & 0xff) == VEC_TRAP0;
@@ -37,5 +52,33 @@ static inline unsigned long regs_return_value(struct pt_regs *regs)
 	return regs->a0;
 }
 
+/* Valid only for Kernel mode traps. */
+static inline unsigned long kernel_stack_pointer(struct pt_regs *regs)
+{
+	return regs->usp;
+}
+
+extern int regs_query_register_offset(const char *name);
+extern unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs,
+						unsigned int n);
+
+/*
+ * regs_get_register() - get register value from its offset
+ * @regs:      pt_regs from which register value is gotten
+ * @offset:    offset of the register.
+ *
+ * regs_get_register returns the value of a register whose offset from @regs.
+ * The @offset is the offset of the register in struct pt_regs.
+ * If @offset is bigger than MAX_REG_OFFSET, this returns 0.
+ */
+static inline unsigned long regs_get_register(struct pt_regs *regs,
+						unsigned int offset)
+{
+	if (unlikely(offset > MAX_REG_OFFSET))
+		return 0;
+
+	return *(unsigned long *)((unsigned long)regs + offset);
+}
+
 #endif /* __ASSEMBLY__ */
 #endif /* __ASM_CSKY_PTRACE_H */

arch/csky/include/asm/thread_info.h

@@ -57,6 +57,7 @@ static inline struct thread_info *current_thread_info(void)
 #define TIF_SYSCALL_TRACE	3	/* syscall trace active */
 #define TIF_SYSCALL_TRACEPOINT	4       /* syscall tracepoint instrumentation */
 #define TIF_SYSCALL_AUDIT	5	/* syscall auditing */
+#define TIF_UPROBE		6	/* uprobe breakpoint or singlestep */
 #define TIF_POLLING_NRFLAG	16	/* poll_idle() is TIF_NEED_RESCHED */
 #define TIF_MEMDIE		18      /* is terminating due to OOM killer */
 #define TIF_RESTORE_SIGMASK	20	/* restore signal mask in do_signal() */
@@ -68,6 +69,7 @@ static inline struct thread_info *current_thread_info(void)
 #define _TIF_SYSCALL_TRACE	(1 << TIF_SYSCALL_TRACE)
 #define _TIF_SYSCALL_TRACEPOINT	(1 << TIF_SYSCALL_TRACEPOINT)
 #define _TIF_SYSCALL_AUDIT	(1 << TIF_SYSCALL_AUDIT)
+#define _TIF_UPROBE		(1 << TIF_UPROBE)
 #define _TIF_POLLING_NRFLAG	(1 << TIF_POLLING_NRFLAG)
 #define _TIF_MEMDIE		(1 << TIF_MEMDIE)
 #define _TIF_RESTORE_SIGMASK	(1 << TIF_RESTORE_SIGMASK)

arch/csky/include/asm/uprobes.h

@@ -0,0 +1,33 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#ifndef __ASM_CSKY_UPROBES_H
+#define __ASM_CSKY_UPROBES_H
+
+#include <asm/probes.h>
+
+#define MAX_UINSN_BYTES		4
+
+#define UPROBE_SWBP_INSN	USR_BKPT
+#define UPROBE_SWBP_INSN_SIZE	2
+#define UPROBE_XOL_SLOT_BYTES	MAX_UINSN_BYTES
+
+typedef u32 uprobe_opcode_t;
+
+struct arch_uprobe_task {
+	unsigned long   saved_trap_no;
+};
+
+struct arch_uprobe {
+	union {
+		u8 insn[MAX_UINSN_BYTES];
+		u8 ixol[MAX_UINSN_BYTES];
+	};
+	struct arch_probe_insn api;
+	unsigned long insn_size;
+	bool simulate;
+};
+
+int uprobe_breakpoint_handler(struct pt_regs *regs);
+int uprobe_single_step_handler(struct pt_regs *regs);
+
+#endif /* __ASM_CSKY_UPROBES_H */