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Fri, 15 Jan 2021 08:50:35 -0800 (PST) Received: from bobo.ibm.com ([124.170.13.62]) by smtp.gmail.com with ESMTPSA id u1sm8455477pjr.51.2021.01.15.08.50.32 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 15 Jan 2021 08:50:34 -0800 (PST) From: Nicholas Piggin To: linuxppc-dev@lists.ozlabs.org Subject: [PATCH v6 05/39] powerpc: remove arguments from fault handler functions Date: Sat, 16 Jan 2021 02:49:38 +1000 Message-Id: <20210115165012.1260253-6-npiggin@gmail.com> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20210115165012.1260253-1-npiggin@gmail.com> References: <20210115165012.1260253-1-npiggin@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Nicholas Piggin Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" Make mm fault handlers all just take the pt_regs * argument and load DAR/DSISR from that. Make those that return a value return long. This is done to make the function signatures match other handlers, which will help with a future patch to add wrappers. Explicit arguments could be added for performance but that would require more wrapper macro variants. Signed-off-by: Nicholas Piggin --- arch/powerpc/include/asm/asm-prototypes.h | 4 ++-- arch/powerpc/include/asm/book3s/64/mmu-hash.h | 2 +- arch/powerpc/include/asm/bug.h | 2 +- arch/powerpc/kernel/entry_32.S | 7 +------ arch/powerpc/kernel/exceptions-64e.S | 2 -- arch/powerpc/kernel/exceptions-64s.S | 17 ++++------------- arch/powerpc/kernel/head_40x.S | 10 +++++----- arch/powerpc/kernel/head_8xx.S | 6 +++--- arch/powerpc/kernel/head_book3s_32.S | 5 ++--- arch/powerpc/kernel/head_booke.h | 4 +--- arch/powerpc/mm/book3s64/hash_utils.c | 8 +++++--- arch/powerpc/mm/book3s64/slb.c | 11 +++++++---- arch/powerpc/mm/fault.c | 5 ++--- 13 files changed, 34 insertions(+), 49 deletions(-) diff --git a/arch/powerpc/include/asm/asm-prototypes.h b/arch/powerpc/include/asm/asm-prototypes.h index d0b832cbbec8..22c9d08fa3a4 100644 --- a/arch/powerpc/include/asm/asm-prototypes.h +++ b/arch/powerpc/include/asm/asm-prototypes.h @@ -82,8 +82,8 @@ void kernel_bad_stack(struct pt_regs *regs); void system_reset_exception(struct pt_regs *regs); void machine_check_exception(struct pt_regs *regs); void emulation_assist_interrupt(struct pt_regs *regs); -long do_slb_fault(struct pt_regs *regs, unsigned long ea); -void do_bad_slb_fault(struct pt_regs *regs, unsigned long ea, long err); +long do_slb_fault(struct pt_regs *regs); +void do_bad_slb_fault(struct pt_regs *regs); /* signals, syscalls and interrupts */ long sys_swapcontext(struct ucontext __user *old_ctx, diff --git a/arch/powerpc/include/asm/book3s/64/mmu-hash.h b/arch/powerpc/include/asm/book3s/64/mmu-hash.h index 60a669379aa0..b9968e297da2 100644 --- a/arch/powerpc/include/asm/book3s/64/mmu-hash.h +++ b/arch/powerpc/include/asm/book3s/64/mmu-hash.h @@ -454,7 +454,7 @@ static inline unsigned long hpt_hash(unsigned long vpn, #define HPTE_NOHPTE_UPDATE 0x2 #define HPTE_USE_KERNEL_KEY 0x4 -int do_hash_fault(struct pt_regs *regs, unsigned long ea, unsigned long dsisr); +long do_hash_fault(struct pt_regs *regs); extern int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid, pte_t *ptep, unsigned long trap, unsigned long flags, int ssize, int subpage_prot); diff --git a/arch/powerpc/include/asm/bug.h b/arch/powerpc/include/asm/bug.h index 464f8ca8a5c9..f7827e993196 100644 --- a/arch/powerpc/include/asm/bug.h +++ b/arch/powerpc/include/asm/bug.h @@ -111,7 +111,7 @@ #ifndef __ASSEMBLY__ struct pt_regs; -extern int do_page_fault(struct pt_regs *, unsigned long, unsigned long); +long do_page_fault(struct pt_regs *); extern void bad_page_fault(struct pt_regs *, unsigned long, int); void __bad_page_fault(struct pt_regs *regs, unsigned long address, int sig); extern void _exception(int, struct pt_regs *, int, unsigned long); diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S index 238eacfda7b0..d6ea3f2d6cc0 100644 --- a/arch/powerpc/kernel/entry_32.S +++ b/arch/powerpc/kernel/entry_32.S @@ -276,8 +276,7 @@ reenable_mmu: * We save a bunch of GPRs, * r3 can be different from GPR3(r1) at this point, r9 and r11 * contains the old MSR and handler address respectively, - * r4 & r5 can contain page fault arguments that need to be passed - * along as well. r0, r6-r8, r12, CCR, CTR, XER etc... are left + * r0, r4-r8, r12, CCR, CTR, XER etc... are left * clobbered as they aren't useful past this point. */ @@ -285,15 +284,11 @@ reenable_mmu: stw r9,8(r1) stw r11,12(r1) stw r3,16(r1) - stw r4,20(r1) - stw r5,24(r1) /* If we are disabling interrupts (normal case), simply log it with * lockdep */ 1: bl trace_hardirqs_off - lwz r5,24(r1) - lwz r4,20(r1) lwz r3,16(r1) lwz r11,12(r1) lwz r9,8(r1) diff --git a/arch/powerpc/kernel/exceptions-64e.S b/arch/powerpc/kernel/exceptions-64e.S index 74d07dc0bb48..43e71d86dcbf 100644 --- a/arch/powerpc/kernel/exceptions-64e.S +++ b/arch/powerpc/kernel/exceptions-64e.S @@ -1011,8 +1011,6 @@ storage_fault_common: std r14,_DAR(r1) std r15,_DSISR(r1) addi r3,r1,STACK_FRAME_OVERHEAD - mr r4,r14 - mr r5,r15 ld r14,PACA_EXGEN+EX_R14(r13) ld r15,PACA_EXGEN+EX_R15(r13) bl do_page_fault diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S index 07aba8af99d3..839dcb94eea7 100644 --- a/arch/powerpc/kernel/exceptions-64s.S +++ b/arch/powerpc/kernel/exceptions-64s.S @@ -1438,10 +1438,9 @@ EXC_VIRT_BEGIN(data_access, 0x4300, 0x80) EXC_VIRT_END(data_access, 0x4300, 0x80) EXC_COMMON_BEGIN(data_access_common) GEN_COMMON data_access - ld r4,_DAR(r1) - ld r5,_DSISR(r1) + ld r4,_DSISR(r1) addi r3,r1,STACK_FRAME_OVERHEAD - andis. r0,r5,DSISR_DABRMATCH@h + andis. r0,r4,DSISR_DABRMATCH@h bne- 1f BEGIN_MMU_FTR_SECTION bl do_hash_fault @@ -1504,10 +1503,9 @@ EXC_VIRT_BEGIN(data_access_slb, 0x4380, 0x80) EXC_VIRT_END(data_access_slb, 0x4380, 0x80) EXC_COMMON_BEGIN(data_access_slb_common) GEN_COMMON data_access_slb - ld r4,_DAR(r1) - addi r3,r1,STACK_FRAME_OVERHEAD BEGIN_MMU_FTR_SECTION /* HPT case, do SLB fault */ + addi r3,r1,STACK_FRAME_OVERHEAD bl do_slb_fault cmpdi r3,0 bne- 1f @@ -1519,8 +1517,6 @@ MMU_FTR_SECTION_ELSE ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_TYPE_RADIX) std r3,RESULT(r1) RECONCILE_IRQ_STATE(r10, r11) - ld r4,_DAR(r1) - ld r5,RESULT(r1) addi r3,r1,STACK_FRAME_OVERHEAD bl do_bad_slb_fault b interrupt_return @@ -1555,8 +1551,6 @@ EXC_VIRT_BEGIN(instruction_access, 0x4400, 0x80) EXC_VIRT_END(instruction_access, 0x4400, 0x80) EXC_COMMON_BEGIN(instruction_access_common) GEN_COMMON instruction_access - ld r4,_DAR(r1) - ld r5,_DSISR(r1) addi r3,r1,STACK_FRAME_OVERHEAD BEGIN_MMU_FTR_SECTION bl do_hash_fault @@ -1602,10 +1596,9 @@ EXC_VIRT_BEGIN(instruction_access_slb, 0x4480, 0x80) EXC_VIRT_END(instruction_access_slb, 0x4480, 0x80) EXC_COMMON_BEGIN(instruction_access_slb_common) GEN_COMMON instruction_access_slb - ld r4,_DAR(r1) - addi r3,r1,STACK_FRAME_OVERHEAD BEGIN_MMU_FTR_SECTION /* HPT case, do SLB fault */ + addi r3,r1,STACK_FRAME_OVERHEAD bl do_slb_fault cmpdi r3,0 bne- 1f @@ -1617,8 +1610,6 @@ MMU_FTR_SECTION_ELSE ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_TYPE_RADIX) std r3,RESULT(r1) RECONCILE_IRQ_STATE(r10, r11) - ld r4,_DAR(r1) - ld r5,RESULT(r1) addi r3,r1,STACK_FRAME_OVERHEAD bl do_bad_slb_fault b interrupt_return diff --git a/arch/powerpc/kernel/head_40x.S b/arch/powerpc/kernel/head_40x.S index a1ae00689e0f..3c5577ac4dc8 100644 --- a/arch/powerpc/kernel/head_40x.S +++ b/arch/powerpc/kernel/head_40x.S @@ -179,9 +179,9 @@ _ENTRY(saved_ksp_limit) */ START_EXCEPTION(0x0300, DataStorage) EXCEPTION_PROLOG - mfspr r5, SPRN_ESR /* Grab the ESR, save it, pass arg3 */ + mfspr r5, SPRN_ESR /* Grab the ESR, save it */ stw r5, _ESR(r11) - mfspr r4, SPRN_DEAR /* Grab the DEAR, save it, pass arg2 */ + mfspr r4, SPRN_DEAR /* Grab the DEAR, save it */ stw r4, _DEAR(r11) EXC_XFER_LITE(0x300, handle_page_fault) @@ -191,9 +191,9 @@ _ENTRY(saved_ksp_limit) */ START_EXCEPTION(0x0400, InstructionAccess) EXCEPTION_PROLOG - mr r4,r12 /* Pass SRR0 as arg2 */ - stw r4, _DEAR(r11) - li r5,0 /* Pass zero as arg3 */ + li r5,0 + stw r5, _ESR(r11) /* Zero ESR */ + stw r12, _DEAR(r11) /* SRR0 as DEAR */ EXC_XFER_LITE(0x400, handle_page_fault) /* 0x0500 - External Interrupt Exception */ diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S index 52702f3db6df..0b2c247cfdff 100644 --- a/arch/powerpc/kernel/head_8xx.S +++ b/arch/powerpc/kernel/head_8xx.S @@ -312,14 +312,14 @@ DataStoreTLBMiss: . = 0x1300 InstructionTLBError: EXCEPTION_PROLOG - mr r4,r12 andis. r5,r9,DSISR_SRR1_MATCH_32S@h /* Filter relevant SRR1 bits */ andis. r10,r9,SRR1_ISI_NOPT@h beq+ .Litlbie - tlbie r4 + tlbie r12 /* 0x400 is InstructionAccess exception, needed by bad_page_fault() */ .Litlbie: - stw r4, _DAR(r11) + stw r12, _DAR(r11) + stw r5, _DSISR(r11) EXC_XFER_LITE(0x400, handle_page_fault) /* This is the data TLB error on the MPC8xx. This could be due to diff --git a/arch/powerpc/kernel/head_book3s_32.S b/arch/powerpc/kernel/head_book3s_32.S index fc9a12768a14..94ad1372c490 100644 --- a/arch/powerpc/kernel/head_book3s_32.S +++ b/arch/powerpc/kernel/head_book3s_32.S @@ -352,9 +352,9 @@ BEGIN_MMU_FTR_SECTION bl hash_page END_MMU_FTR_SECTION_IFSET(MMU_FTR_HPTE_TABLE) #endif /* CONFIG_VMAP_STACK */ -1: mr r4,r12 andis. r5,r9,DSISR_SRR1_MATCH_32S@h /* Filter relevant SRR1 bits */ - stw r4, _DAR(r11) + stw r5, _DSISR(r11) + stw r12, _DAR(r11) EXC_XFER_LITE(0x400, handle_page_fault) /* External interrupt */ @@ -676,7 +676,6 @@ handle_page_fault_tramp_1: #ifdef CONFIG_VMAP_STACK EXCEPTION_PROLOG_2 handle_dar_dsisr=1 #endif - lwz r4, _DAR(r11) lwz r5, _DSISR(r11) /* fall through */ handle_page_fault_tramp_2: diff --git a/arch/powerpc/kernel/head_booke.h b/arch/powerpc/kernel/head_booke.h index 74e230c200fb..0fbdacc7fab7 100644 --- a/arch/powerpc/kernel/head_booke.h +++ b/arch/powerpc/kernel/head_booke.h @@ -476,9 +476,7 @@ ALT_FTR_SECTION_END_IFSET(CPU_FTR_EMB_HV) NORMAL_EXCEPTION_PROLOG(INST_STORAGE); \ mfspr r5,SPRN_ESR; /* Grab the ESR and save it */ \ stw r5,_ESR(r11); \ - mr r4,r12; /* Pass SRR0 as arg2 */ \ - stw r4, _DEAR(r11); \ - li r5,0; /* Pass zero as arg3 */ \ + stw r12, _DEAR(r11); /* Pass SRR0 as arg2 */ \ EXC_XFER_LITE(0x0400, handle_page_fault) #define ALIGNMENT_EXCEPTION \ diff --git a/arch/powerpc/mm/book3s64/hash_utils.c b/arch/powerpc/mm/book3s64/hash_utils.c index e866cae57e2f..9a499af3eebf 100644 --- a/arch/powerpc/mm/book3s64/hash_utils.c +++ b/arch/powerpc/mm/book3s64/hash_utils.c @@ -1512,13 +1512,15 @@ int hash_page(unsigned long ea, unsigned long access, unsigned long trap, } EXPORT_SYMBOL_GPL(hash_page); -int do_hash_fault(struct pt_regs *regs, unsigned long ea, unsigned long dsisr) +long do_hash_fault(struct pt_regs *regs) { + unsigned long ea = regs->dar; + unsigned long dsisr = regs->dsisr; unsigned long access = _PAGE_PRESENT | _PAGE_READ; unsigned long flags = 0; struct mm_struct *mm; unsigned int region_id; - int err; + long err; if (unlikely(dsisr & (DSISR_BAD_FAULT_64S | DSISR_KEYFAULT))) goto page_fault; @@ -1582,7 +1584,7 @@ int do_hash_fault(struct pt_regs *regs, unsigned long ea, unsigned long dsisr) } else if (err) { page_fault: - err = do_page_fault(regs, ea, dsisr); + err = do_page_fault(regs); } return err; diff --git a/arch/powerpc/mm/book3s64/slb.c b/arch/powerpc/mm/book3s64/slb.c index 584567970c11..985902ce0272 100644 --- a/arch/powerpc/mm/book3s64/slb.c +++ b/arch/powerpc/mm/book3s64/slb.c @@ -813,8 +813,9 @@ static long slb_allocate_user(struct mm_struct *mm, unsigned long ea) return slb_insert_entry(ea, context, flags, ssize, false); } -long do_slb_fault(struct pt_regs *regs, unsigned long ea) +long do_slb_fault(struct pt_regs *regs) { + unsigned long ea = regs->dar; unsigned long id = get_region_id(ea); /* IRQs are not reconciled here, so can't check irqs_disabled */ @@ -865,13 +866,15 @@ long do_slb_fault(struct pt_regs *regs, unsigned long ea) } } -void do_bad_slb_fault(struct pt_regs *regs, unsigned long ea, long err) +void do_bad_slb_fault(struct pt_regs *regs) { + int err = regs->result; + if (err == -EFAULT) { if (user_mode(regs)) - _exception(SIGSEGV, regs, SEGV_BNDERR, ea); + _exception(SIGSEGV, regs, SEGV_BNDERR, regs->dar); else - bad_page_fault(regs, ea, SIGSEGV); + bad_page_fault(regs, regs->dar, SIGSEGV); } else if (err == -EINVAL) { unrecoverable_exception(regs); } else { diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c index 8961b44f350c..273ff845eccf 100644 --- a/arch/powerpc/mm/fault.c +++ b/arch/powerpc/mm/fault.c @@ -542,12 +542,11 @@ static int __do_page_fault(struct pt_regs *regs, unsigned long address, } NOKPROBE_SYMBOL(__do_page_fault); -int do_page_fault(struct pt_regs *regs, unsigned long address, - unsigned long error_code) +long do_page_fault(struct pt_regs *regs) { const struct exception_table_entry *entry; enum ctx_state prev_state = exception_enter(); - int rc = __do_page_fault(regs, address, error_code); + int rc = __do_page_fault(regs, regs->dar, regs->dsisr); exception_exit(prev_state); if (likely(!rc)) return 0; -- 2.23.0