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Diffstat (limited to 'arch/s390/kernel/kprobes.c')
-rw-r--r--arch/s390/kernel/kprobes.c71
1 files changed, 12 insertions, 59 deletions
diff --git a/arch/s390/kernel/kprobes.c b/arch/s390/kernel/kprobes.c
index f0cf20d4b3..05c83505e9 100644
--- a/arch/s390/kernel/kprobes.c
+++ b/arch/s390/kernel/kprobes.c
@@ -9,7 +9,6 @@
#define pr_fmt(fmt) "kprobes: " fmt
-#include <linux/moduleloader.h>
#include <linux/kprobes.h>
#include <linux/ptrace.h>
#include <linux/preempt.h>
@@ -21,10 +20,10 @@
#include <linux/slab.h>
#include <linux/hardirq.h>
#include <linux/ftrace.h>
+#include <linux/execmem.h>
#include <asm/set_memory.h>
#include <asm/sections.h>
#include <asm/dis.h>
-#include "kprobes.h"
#include "entry.h"
DEFINE_PER_CPU(struct kprobe *, current_kprobe);
@@ -32,39 +31,17 @@ DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk);
struct kretprobe_blackpoint kretprobe_blacklist[] = { };
-static int insn_page_in_use;
-
void *alloc_insn_page(void)
{
void *page;
- page = module_alloc(PAGE_SIZE);
+ page = execmem_alloc(EXECMEM_KPROBES, PAGE_SIZE);
if (!page)
return NULL;
set_memory_rox((unsigned long)page, 1);
return page;
}
-static void *alloc_s390_insn_page(void)
-{
- if (xchg(&insn_page_in_use, 1) == 1)
- return NULL;
- return &kprobes_insn_page;
-}
-
-static void free_s390_insn_page(void *page)
-{
- xchg(&insn_page_in_use, 0);
-}
-
-struct kprobe_insn_cache kprobe_s390_insn_slots = {
- .mutex = __MUTEX_INITIALIZER(kprobe_s390_insn_slots.mutex),
- .alloc = alloc_s390_insn_page,
- .free = free_s390_insn_page,
- .pages = LIST_HEAD_INIT(kprobe_s390_insn_slots.pages),
- .insn_size = MAX_INSN_SIZE,
-};
-
static void copy_instruction(struct kprobe *p)
{
kprobe_opcode_t insn[MAX_INSN_SIZE];
@@ -78,10 +55,10 @@ static void copy_instruction(struct kprobe *p)
if (probe_is_insn_relative_long(&insn[0])) {
/*
* For pc-relative instructions in RIL-b or RIL-c format patch
- * the RI2 displacement field. We have already made sure that
- * the insn slot for the patched instruction is within the same
- * 2GB area as the original instruction (either kernel image or
- * module area). Therefore the new displacement will always fit.
+ * the RI2 displacement field. The insn slot for the to be
+ * patched instruction is within the same 4GB area like the
+ * original instruction. Therefore the new displacement will
+ * always fit.
*/
disp = *(s32 *)&insn[1];
addr = (u64)(unsigned long)p->addr;
@@ -93,34 +70,6 @@ static void copy_instruction(struct kprobe *p)
}
NOKPROBE_SYMBOL(copy_instruction);
-static int s390_get_insn_slot(struct kprobe *p)
-{
- /*
- * Get an insn slot that is within the same 2GB area like the original
- * instruction. That way instructions with a 32bit signed displacement
- * field can be patched and executed within the insn slot.
- */
- p->ainsn.insn = NULL;
- if (is_kernel((unsigned long)p->addr))
- p->ainsn.insn = get_s390_insn_slot();
- else if (is_module_addr(p->addr))
- p->ainsn.insn = get_insn_slot();
- return p->ainsn.insn ? 0 : -ENOMEM;
-}
-NOKPROBE_SYMBOL(s390_get_insn_slot);
-
-static void s390_free_insn_slot(struct kprobe *p)
-{
- if (!p->ainsn.insn)
- return;
- if (is_kernel((unsigned long)p->addr))
- free_s390_insn_slot(p->ainsn.insn, 0);
- else
- free_insn_slot(p->ainsn.insn, 0);
- p->ainsn.insn = NULL;
-}
-NOKPROBE_SYMBOL(s390_free_insn_slot);
-
/* Check if paddr is at an instruction boundary */
static bool can_probe(unsigned long paddr)
{
@@ -174,7 +123,8 @@ int arch_prepare_kprobe(struct kprobe *p)
/* Make sure the probe isn't going on a difficult instruction */
if (probe_is_prohibited_opcode(p->addr))
return -EINVAL;
- if (s390_get_insn_slot(p))
+ p->ainsn.insn = get_insn_slot();
+ if (!p->ainsn.insn)
return -ENOMEM;
copy_instruction(p);
return 0;
@@ -216,7 +166,10 @@ NOKPROBE_SYMBOL(arch_disarm_kprobe);
void arch_remove_kprobe(struct kprobe *p)
{
- s390_free_insn_slot(p);
+ if (!p->ainsn.insn)
+ return;
+ free_insn_slot(p->ainsn.insn, 0);
+ p->ainsn.insn = NULL;
}
NOKPROBE_SYMBOL(arch_remove_kprobe);