[PATCH v4 07/12] s390/ptrace: Convert function macros to inline functions
From: Jens Remus <hidden>
Date: 2026-01-27 15:20:00
Also in:
bpf, linux-s390, lkml
Subsystem:
ptrace support, s390 architecture, the rest · Maintainers:
Oleg Nesterov, Heiko Carstens, Vasily Gorbik, Alexander Gordeev, Linus Torvalds
Convert the function macros user_mode(), instruction_pointer(), and
user_stack_pointer() to inline functions, to align their definition
with x86 and arm64.
Use const qualifier on struct pt_regs pointer parameters to prevent
compiler warnings:
arch/s390/kernel/stacktrace.c: In function ‘arch_stack_walk_user_common’:
arch/s390/kernel/stacktrace.c:114:34: warning: passing argument 1 of
‘instruction_pointer’ discards ‘const’ qualifier from pointer target
type [-Wdiscarded-qualifiers]
...
arch/s390/kernel/stacktrace.c:117:48: warning: passing argument 1 of
‘user_stack_pointer’ discards ‘const’ qualifier from pointer target
type [-Wdiscarded-qualifiers]
...
While at it add const qualifier to all struct pt_regs pointer parameters
that are accessed read-only and use __always_inline instead of inline to
harmonize the helper functions.
[hca@linux.ibm.com: Use psw_bits() helper]
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Jens Remus <redacted>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
---
Notes (jremus):
Changes in v4:
- New patch. Split out "while at it" changes from patch "s390/ptrace:
Provide frame_pointer()" to go upstream separately. (Heiko)
arch/s390/include/asm/ptrace.h | 37 ++++++++++++++++++++++++----------
1 file changed, 26 insertions(+), 11 deletions(-)
diff --git a/arch/s390/include/asm/ptrace.h b/arch/s390/include/asm/ptrace.h
index 962cf042c66d..e6ec0ccf3d73 100644
--- a/arch/s390/include/asm/ptrace.h
+++ b/arch/s390/include/asm/ptrace.h@@ -214,16 +214,23 @@ void update_cr_regs(struct task_struct *task); #define arch_has_single_step() (1) #define arch_has_block_step() (1) -#define user_mode(regs) (((regs)->psw.mask & PSW_MASK_PSTATE) != 0) -#define instruction_pointer(regs) ((regs)->psw.addr) -#define user_stack_pointer(regs)((regs)->gprs[15]) #define profile_pc(regs) instruction_pointer(regs) -static inline long regs_return_value(struct pt_regs *regs) +static __always_inline bool user_mode(const struct pt_regs *regs) +{ + return psw_bits(regs->psw).pstate; +} + +static inline long regs_return_value(const struct pt_regs *regs) { return regs->gprs[2]; } +static __always_inline unsigned long instruction_pointer(const struct pt_regs *regs) +{ + return regs->psw.addr; +} + static inline void instruction_pointer_set(struct pt_regs *regs, unsigned long val) {
@@ -233,19 +240,26 @@ static inline void instruction_pointer_set(struct pt_regs *regs, int regs_query_register_offset(const char *name); const char *regs_query_register_name(unsigned int offset); -static __always_inline unsigned long kernel_stack_pointer(struct pt_regs *regs) +static __always_inline unsigned long kernel_stack_pointer(const struct pt_regs *regs) +{ + return regs->gprs[15]; +} + +static __always_inline unsigned long user_stack_pointer(const struct pt_regs *regs) { return regs->gprs[15]; } -static __always_inline unsigned long regs_get_register(struct pt_regs *regs, unsigned int offset) +static __always_inline unsigned long regs_get_register(const struct pt_regs *regs, + unsigned int offset) { if (offset >= NUM_GPRS) return 0; return regs->gprs[offset]; } -static __always_inline int regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr) +static __always_inline int regs_within_kernel_stack(const struct pt_regs *regs, + unsigned long addr) { unsigned long ksp = kernel_stack_pointer(regs);
@@ -261,7 +275,8 @@ static __always_inline int regs_within_kernel_stack(struct pt_regs *regs, unsign * is specifined by @regs. If the @n th entry is NOT in the kernel stack, * this returns 0. */ -static __always_inline unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n) +static __always_inline unsigned long regs_get_kernel_stack_nth(const struct pt_regs *regs, + unsigned int n) { unsigned long addr;
@@ -278,8 +293,8 @@ static __always_inline unsigned long regs_get_kernel_stack_nth(struct pt_regs *r * * regs_get_kernel_argument() returns @n th argument of the function call. */ -static inline unsigned long regs_get_kernel_argument(struct pt_regs *regs, - unsigned int n) +static __always_inline unsigned long regs_get_kernel_argument(const struct pt_regs *regs, + unsigned int n) { unsigned int argoffset = STACK_FRAME_OVERHEAD / sizeof(long);
@@ -290,7 +305,7 @@ static inline unsigned long regs_get_kernel_argument(struct pt_regs *regs, return regs_get_kernel_stack_nth(regs, argoffset + n); } -static inline void regs_set_return_value(struct pt_regs *regs, unsigned long rc) +static __always_inline void regs_set_return_value(struct pt_regs *regs, unsigned long rc) { regs->gprs[2] = rc; }
--
2.51.0