[PATCH 03/12] x86: Implement hw_breakpoint_arch_parse()
From: Frederic Weisbecker
Date: Fri May 18 2018 - 21:50:17 EST
Migrate to the new API in order to remove arch_validate_hwbkpt_settings()
that clumsily mixes up architecture validation and commit.
Original-patch-by: Andy Lutomirski <luto@xxxxxxxxxx>
Signed-off-by: Frederic Weisbecker <frederic@xxxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Andy Lutomirski <luto@xxxxxxxxxx>
Cc: Yoshinori Sato <ysato@xxxxxxxxxxxxxxxxxxxx>
Cc: Rich Felker <dalias@xxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Will Deacon <will.deacon@xxxxxxx>
Cc: Mark Rutland <mark.rutland@xxxxxxx>
Cc: Max Filippov <jcmvbkbc@xxxxxxxxx>
Cc: Chris Zankel <chris@xxxxxxxxxx>
Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Joel Fernandes <joel.opensrc@xxxxxxxxx>
---
arch/x86/include/asm/hw_breakpoint.h | 6 +++-
arch/x86/kernel/hw_breakpoint.c | 60 ++++++++++++++++++------------------
2 files changed, 35 insertions(+), 31 deletions(-)
diff --git a/arch/x86/include/asm/hw_breakpoint.h b/arch/x86/include/asm/hw_breakpoint.h
index 7892459..8cc161f 100644
--- a/arch/x86/include/asm/hw_breakpoint.h
+++ b/arch/x86/include/asm/hw_breakpoint.h
@@ -49,11 +49,15 @@ static inline int hw_breakpoint_slots(int type)
return HBP_NUM;
}
+struct perf_event_attr;
struct perf_event;
struct pmu;
extern int arch_check_bp_in_kernelspace(struct arch_hw_breakpoint *hw);
-extern int arch_validate_hwbkpt_settings(struct perf_event *bp);
+extern int hw_breakpoint_arch_parse(struct perf_event *bp,
+ struct perf_event_attr *attr,
+ struct arch_hw_breakpoint *hw);
+#define hw_breakpoint_arch_parse hw_breakpoint_arch_parse
extern int hw_breakpoint_exceptions_notify(struct notifier_block *unused,
unsigned long val, void *data);
diff --git a/arch/x86/kernel/hw_breakpoint.c b/arch/x86/kernel/hw_breakpoint.c
index c433791..a8bceb0 100644
--- a/arch/x86/kernel/hw_breakpoint.c
+++ b/arch/x86/kernel/hw_breakpoint.c
@@ -239,19 +239,20 @@ int arch_check_bp_in_kernelspace(struct arch_hw_breakpoint *hw)
return (va >= TASK_SIZE_MAX) || ((va + len - 1) >= TASK_SIZE_MAX);
}
-static int arch_build_bp_info(struct perf_event *bp)
+static int arch_build_bp_info(struct perf_event *bp,
+ struct perf_event_attr *attr,
+ struct arch_hw_breakpoint *hw)
{
- struct arch_hw_breakpoint *info = counter_arch_bp(bp);
-
- info->address = bp->attr.bp_addr;
+ hw->address = attr->bp_addr;
+ hw->mask = 0;
/* Type */
- switch (bp->attr.bp_type) {
+ switch (attr->bp_type) {
case HW_BREAKPOINT_W:
- info->type = X86_BREAKPOINT_WRITE;
+ hw->type = X86_BREAKPOINT_WRITE;
break;
case HW_BREAKPOINT_W | HW_BREAKPOINT_R:
- info->type = X86_BREAKPOINT_RW;
+ hw->type = X86_BREAKPOINT_RW;
break;
case HW_BREAKPOINT_X:
/*
@@ -259,23 +260,23 @@ static int arch_build_bp_info(struct perf_event *bp)
* acceptable for kprobes. On non-kprobes kernels, we don't
* allow kernel breakpoints at all.
*/
- if (bp->attr.bp_addr >= TASK_SIZE_MAX) {
+ if (attr->bp_addr >= TASK_SIZE_MAX) {
#ifdef CONFIG_KPROBES
- if (within_kprobe_blacklist(bp->attr.bp_addr))
+ if (within_kprobe_blacklist(attr->bp_addr))
return -EINVAL;
#else
return -EINVAL;
#endif
}
- info->type = X86_BREAKPOINT_EXECUTE;
+ hw->type = X86_BREAKPOINT_EXECUTE;
/*
* x86 inst breakpoints need to have a specific undefined len.
* But we still need to check userspace is not trying to setup
* an unsupported length, to get a range breakpoint for example.
*/
- if (bp->attr.bp_len == sizeof(long)) {
- info->len = X86_BREAKPOINT_LEN_X;
+ if (attr->bp_len == sizeof(long)) {
+ hw->len = X86_BREAKPOINT_LEN_X;
return 0;
}
default:
@@ -283,28 +284,26 @@ static int arch_build_bp_info(struct perf_event *bp)
}
/* Len */
- info->mask = 0;
-
- switch (bp->attr.bp_len) {
+ switch (attr->bp_len) {
case HW_BREAKPOINT_LEN_1:
- info->len = X86_BREAKPOINT_LEN_1;
+ hw->len = X86_BREAKPOINT_LEN_1;
break;
case HW_BREAKPOINT_LEN_2:
- info->len = X86_BREAKPOINT_LEN_2;
+ hw->len = X86_BREAKPOINT_LEN_2;
break;
case HW_BREAKPOINT_LEN_4:
- info->len = X86_BREAKPOINT_LEN_4;
+ hw->len = X86_BREAKPOINT_LEN_4;
break;
#ifdef CONFIG_X86_64
case HW_BREAKPOINT_LEN_8:
- info->len = X86_BREAKPOINT_LEN_8;
+ hw->len = X86_BREAKPOINT_LEN_8;
break;
#endif
default:
/* AMD range breakpoint */
- if (!is_power_of_2(bp->attr.bp_len))
+ if (!is_power_of_2(attr->bp_len))
return -EINVAL;
- if (bp->attr.bp_addr & (bp->attr.bp_len - 1))
+ if (attr->bp_addr & (attr->bp_len - 1))
return -EINVAL;
if (!boot_cpu_has(X86_FEATURE_BPEXT))
@@ -317,8 +316,8 @@ static int arch_build_bp_info(struct perf_event *bp)
* breakpoints, then we'll have to check for kprobe-blacklisted
* addresses anywhere in the range.
*/
- info->mask = bp->attr.bp_len - 1;
- info->len = X86_BREAKPOINT_LEN_1;
+ hw->mask = attr->bp_len - 1;
+ hw->len = X86_BREAKPOINT_LEN_1;
}
return 0;
@@ -327,22 +326,23 @@ static int arch_build_bp_info(struct perf_event *bp)
/*
* Validate the arch-specific HW Breakpoint register settings
*/
-int arch_validate_hwbkpt_settings(struct perf_event *bp)
+int hw_breakpoint_arch_parse(struct perf_event *bp,
+ struct perf_event_attr *attr,
+ struct arch_hw_breakpoint *hw)
{
- struct arch_hw_breakpoint *info = counter_arch_bp(bp);
unsigned int align;
int ret;
- ret = arch_build_bp_info(bp);
+ ret = arch_build_bp_info(bp, attr, hw);
if (ret)
return ret;
- switch (info->len) {
+ switch (hw->len) {
case X86_BREAKPOINT_LEN_1:
align = 0;
- if (info->mask)
- align = info->mask;
+ if (hw->mask)
+ align = hw->mask;
break;
case X86_BREAKPOINT_LEN_2:
align = 1;
@@ -363,7 +363,7 @@ int arch_validate_hwbkpt_settings(struct perf_event *bp)
* Check that the low-order bits of the address are appropriate
* for the alignment implied by len.
*/
- if (info->address & align)
+ if (hw->address & align)
return -EINVAL;
return 0;
--
2.7.4