diff options
Diffstat (limited to 'arch/s390/kernel/kprobes.c')
-rw-r--r-- | arch/s390/kernel/kprobes.c | 71 |
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); |