From 975fab17399a2b29985166181ad80e5f50fa42e9 Mon Sep 17 00:00:00 2001 From: Jan Willeke Date: Mon, 22 Sep 2014 16:37:27 +0200 Subject: [PATCH] s390/uprobes: common library for kprobes and uprobes This patch moves common functions from kprobes.c to probes.c. Thus its possible for uprobes to use them without enabling kprobes. Signed-off-by: Jan Willeke Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky --- arch/s390/include/asm/kprobes.h | 4 + arch/s390/kernel/kprobes.c | 154 +------------------------------ arch/s390/lib/Makefile | 2 + arch/s390/lib/probes.c | 159 ++++++++++++++++++++++++++++++++ 4 files changed, 168 insertions(+), 151 deletions(-) create mode 100644 arch/s390/lib/probes.c diff --git a/arch/s390/include/asm/kprobes.h b/arch/s390/include/asm/kprobes.h index 4176dfe0fba1..98629173ce3b 100644 --- a/arch/s390/include/asm/kprobes.h +++ b/arch/s390/include/asm/kprobes.h @@ -84,6 +84,10 @@ int kprobe_fault_handler(struct pt_regs *regs, int trapnr); int kprobe_exceptions_notify(struct notifier_block *self, unsigned long val, void *data); +int probe_is_prohibited_opcode(u16 *insn); +int probe_get_fixup_type(u16 *insn); +int probe_is_insn_relative_long(u16 *insn); + #define flush_insn_slot(p) do { } while (0) #endif /* _ASM_S390_KPROBES_H */ diff --git a/arch/s390/kernel/kprobes.c b/arch/s390/kernel/kprobes.c index c48a00c9f351..27ae5433fe4d 100644 --- a/arch/s390/kernel/kprobes.c +++ b/arch/s390/kernel/kprobes.c @@ -58,161 +58,13 @@ struct kprobe_insn_cache kprobe_dmainsn_slots = { .insn_size = MAX_INSN_SIZE, }; -static int __kprobes is_prohibited_opcode(kprobe_opcode_t *insn) -{ - if (!is_known_insn((unsigned char *)insn)) - return -EINVAL; - switch (insn[0] >> 8) { - case 0x0c: /* bassm */ - case 0x0b: /* bsm */ - case 0x83: /* diag */ - case 0x44: /* ex */ - case 0xac: /* stnsm */ - case 0xad: /* stosm */ - return -EINVAL; - case 0xc6: - switch (insn[0] & 0x0f) { - case 0x00: /* exrl */ - return -EINVAL; - } - } - switch (insn[0]) { - case 0x0101: /* pr */ - case 0xb25a: /* bsa */ - case 0xb240: /* bakr */ - case 0xb258: /* bsg */ - case 0xb218: /* pc */ - case 0xb228: /* pt */ - case 0xb98d: /* epsw */ - return -EINVAL; - } - return 0; -} - -static int __kprobes get_fixup_type(kprobe_opcode_t *insn) -{ - /* default fixup method */ - int fixup = FIXUP_PSW_NORMAL; - - switch (insn[0] >> 8) { - case 0x05: /* balr */ - case 0x0d: /* basr */ - fixup = FIXUP_RETURN_REGISTER; - /* if r2 = 0, no branch will be taken */ - if ((insn[0] & 0x0f) == 0) - fixup |= FIXUP_BRANCH_NOT_TAKEN; - break; - case 0x06: /* bctr */ - case 0x07: /* bcr */ - fixup = FIXUP_BRANCH_NOT_TAKEN; - break; - case 0x45: /* bal */ - case 0x4d: /* bas */ - fixup = FIXUP_RETURN_REGISTER; - break; - case 0x47: /* bc */ - case 0x46: /* bct */ - case 0x86: /* bxh */ - case 0x87: /* bxle */ - fixup = FIXUP_BRANCH_NOT_TAKEN; - break; - case 0x82: /* lpsw */ - fixup = FIXUP_NOT_REQUIRED; - break; - case 0xb2: /* lpswe */ - if ((insn[0] & 0xff) == 0xb2) - fixup = FIXUP_NOT_REQUIRED; - break; - case 0xa7: /* bras */ - if ((insn[0] & 0x0f) == 0x05) - fixup |= FIXUP_RETURN_REGISTER; - break; - case 0xc0: - if ((insn[0] & 0x0f) == 0x05) /* brasl */ - fixup |= FIXUP_RETURN_REGISTER; - break; - case 0xeb: - switch (insn[2] & 0xff) { - case 0x44: /* bxhg */ - case 0x45: /* bxleg */ - fixup = FIXUP_BRANCH_NOT_TAKEN; - break; - } - break; - case 0xe3: /* bctg */ - if ((insn[2] & 0xff) == 0x46) - fixup = FIXUP_BRANCH_NOT_TAKEN; - break; - case 0xec: - switch (insn[2] & 0xff) { - case 0xe5: /* clgrb */ - case 0xe6: /* cgrb */ - case 0xf6: /* crb */ - case 0xf7: /* clrb */ - case 0xfc: /* cgib */ - case 0xfd: /* cglib */ - case 0xfe: /* cib */ - case 0xff: /* clib */ - fixup = FIXUP_BRANCH_NOT_TAKEN; - break; - } - break; - } - return fixup; -} - -static int __kprobes is_insn_relative_long(kprobe_opcode_t *insn) -{ - /* Check if we have a RIL-b or RIL-c format instruction which - * we need to modify in order to avoid instruction emulation. */ - switch (insn[0] >> 8) { - case 0xc0: - if ((insn[0] & 0x0f) == 0x00) /* larl */ - return true; - break; - case 0xc4: - switch (insn[0] & 0x0f) { - case 0x02: /* llhrl */ - case 0x04: /* lghrl */ - case 0x05: /* lhrl */ - case 0x06: /* llghrl */ - case 0x07: /* sthrl */ - case 0x08: /* lgrl */ - case 0x0b: /* stgrl */ - case 0x0c: /* lgfrl */ - case 0x0d: /* lrl */ - case 0x0e: /* llgfrl */ - case 0x0f: /* strl */ - return true; - } - break; - case 0xc6: - switch (insn[0] & 0x0f) { - case 0x02: /* pfdrl */ - case 0x04: /* cghrl */ - case 0x05: /* chrl */ - case 0x06: /* clghrl */ - case 0x07: /* clhrl */ - case 0x08: /* cgrl */ - case 0x0a: /* clgrl */ - case 0x0c: /* cgfrl */ - case 0x0d: /* crl */ - case 0x0e: /* clgfrl */ - case 0x0f: /* clrl */ - return true; - } - break; - } - return false; -} - static void __kprobes copy_instruction(struct kprobe *p) { s64 disp, new_disp; u64 addr, new_addr; memcpy(p->ainsn.insn, p->addr, insn_length(p->opcode >> 8)); - if (!is_insn_relative_long(p->ainsn.insn)) + if (!probe_is_insn_relative_long(p->ainsn.insn)) return; /* * For pc-relative instructions in RIL-b or RIL-c format patch the @@ -276,7 +128,7 @@ int __kprobes arch_prepare_kprobe(struct kprobe *p) if ((unsigned long) p->addr & 0x01) return -EINVAL; /* Make sure the probe isn't going on a difficult instruction */ - if (is_prohibited_opcode(p->addr)) + if (probe_is_prohibited_opcode(p->addr)) return -EINVAL; if (s390_get_insn_slot(p)) return -ENOMEM; @@ -605,7 +457,7 @@ static void __kprobes resume_execution(struct kprobe *p, struct pt_regs *regs) { struct kprobe_ctlblk *kcb = get_kprobe_ctlblk(); unsigned long ip = regs->psw.addr & PSW_ADDR_INSN; - int fixup = get_fixup_type(p->ainsn.insn); + int fixup = probe_get_fixup_type(p->ainsn.insn); if (fixup & FIXUP_PSW_NORMAL) ip += (unsigned long) p->addr - (unsigned long) p->ainsn.insn; diff --git a/arch/s390/lib/Makefile b/arch/s390/lib/Makefile index c6d752e8bf28..a01df233856f 100644 --- a/arch/s390/lib/Makefile +++ b/arch/s390/lib/Makefile @@ -6,3 +6,5 @@ lib-y += delay.o string.o uaccess.o find.o obj-$(CONFIG_32BIT) += div64.o qrnnd.o ucmpdi2.o mem32.o obj-$(CONFIG_64BIT) += mem64.o lib-$(CONFIG_SMP) += spinlock.o +lib-$(CONFIG_KPROBES) += probes.o +lib-$(CONFIG_UPROBES) += probes.o diff --git a/arch/s390/lib/probes.c b/arch/s390/lib/probes.c new file mode 100644 index 000000000000..c5d64a099719 --- /dev/null +++ b/arch/s390/lib/probes.c @@ -0,0 +1,159 @@ +/* + * Common helper functions for kprobes and uprobes + * + * Copyright IBM Corp. 2014 + */ + +#include +#include + +int probe_is_prohibited_opcode(u16 *insn) +{ + if (!is_known_insn((unsigned char *)insn)) + return -EINVAL; + switch (insn[0] >> 8) { + case 0x0c: /* bassm */ + case 0x0b: /* bsm */ + case 0x83: /* diag */ + case 0x44: /* ex */ + case 0xac: /* stnsm */ + case 0xad: /* stosm */ + return -EINVAL; + case 0xc6: + switch (insn[0] & 0x0f) { + case 0x00: /* exrl */ + return -EINVAL; + } + } + switch (insn[0]) { + case 0x0101: /* pr */ + case 0xb25a: /* bsa */ + case 0xb240: /* bakr */ + case 0xb258: /* bsg */ + case 0xb218: /* pc */ + case 0xb228: /* pt */ + case 0xb98d: /* epsw */ + case 0xe560: /* tbegin */ + case 0xe561: /* tbeginc */ + case 0xb2f8: /* tend */ + return -EINVAL; + } + return 0; +} + +int probe_get_fixup_type(u16 *insn) +{ + /* default fixup method */ + int fixup = FIXUP_PSW_NORMAL; + + switch (insn[0] >> 8) { + case 0x05: /* balr */ + case 0x0d: /* basr */ + fixup = FIXUP_RETURN_REGISTER; + /* if r2 = 0, no branch will be taken */ + if ((insn[0] & 0x0f) == 0) + fixup |= FIXUP_BRANCH_NOT_TAKEN; + break; + case 0x06: /* bctr */ + case 0x07: /* bcr */ + fixup = FIXUP_BRANCH_NOT_TAKEN; + break; + case 0x45: /* bal */ + case 0x4d: /* bas */ + fixup = FIXUP_RETURN_REGISTER; + break; + case 0x47: /* bc */ + case 0x46: /* bct */ + case 0x86: /* bxh */ + case 0x87: /* bxle */ + fixup = FIXUP_BRANCH_NOT_TAKEN; + break; + case 0x82: /* lpsw */ + fixup = FIXUP_NOT_REQUIRED; + break; + case 0xb2: /* lpswe */ + if ((insn[0] & 0xff) == 0xb2) + fixup = FIXUP_NOT_REQUIRED; + break; + case 0xa7: /* bras */ + if ((insn[0] & 0x0f) == 0x05) + fixup |= FIXUP_RETURN_REGISTER; + break; + case 0xc0: + if ((insn[0] & 0x0f) == 0x05) /* brasl */ + fixup |= FIXUP_RETURN_REGISTER; + break; + case 0xeb: + switch (insn[2] & 0xff) { + case 0x44: /* bxhg */ + case 0x45: /* bxleg */ + fixup = FIXUP_BRANCH_NOT_TAKEN; + break; + } + break; + case 0xe3: /* bctg */ + if ((insn[2] & 0xff) == 0x46) + fixup = FIXUP_BRANCH_NOT_TAKEN; + break; + case 0xec: + switch (insn[2] & 0xff) { + case 0xe5: /* clgrb */ + case 0xe6: /* cgrb */ + case 0xf6: /* crb */ + case 0xf7: /* clrb */ + case 0xfc: /* cgib */ + case 0xfd: /* cglib */ + case 0xfe: /* cib */ + case 0xff: /* clib */ + fixup = FIXUP_BRANCH_NOT_TAKEN; + break; + } + break; + } + return fixup; +} + +int probe_is_insn_relative_long(u16 *insn) +{ + /* Check if we have a RIL-b or RIL-c format instruction which + * we need to modify in order to avoid instruction emulation. */ + switch (insn[0] >> 8) { + case 0xc0: + if ((insn[0] & 0x0f) == 0x00) /* larl */ + return true; + break; + case 0xc4: + switch (insn[0] & 0x0f) { + case 0x02: /* llhrl */ + case 0x04: /* lghrl */ + case 0x05: /* lhrl */ + case 0x06: /* llghrl */ + case 0x07: /* sthrl */ + case 0x08: /* lgrl */ + case 0x0b: /* stgrl */ + case 0x0c: /* lgfrl */ + case 0x0d: /* lrl */ + case 0x0e: /* llgfrl */ + case 0x0f: /* strl */ + return true; + } + break; + case 0xc6: + switch (insn[0] & 0x0f) { + case 0x02: /* pfdrl */ + case 0x04: /* cghrl */ + case 0x05: /* chrl */ + case 0x06: /* clghrl */ + case 0x07: /* clhrl */ + case 0x08: /* cgrl */ + case 0x0a: /* clgrl */ + case 0x0c: /* cgfrl */ + case 0x0d: /* crl */ + case 0x0e: /* clgfrl */ + case 0x0f: /* clrl */ + return true; + } + break; + } + return false; +} -- 2.34.1