powerpc: remove arguments from fault handler functions

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 <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210130130852.2952424-7-npiggin@gmail.com

diff --git a/arch/powerpc/include/asm/asm-prototypes.h b/arch/powerpc/include/asm/asm-prototypes.h
index d0b832c..22c9d08 100644 (file)
--- 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 1aa6809..36884bc 100644 (file)
--- a/arch/powerpc/include/asm/book3s/64/mmu-hash.h
+++ b/arch/powerpc/include/asm/book3s/64/mmu-hash.h
@@ -456,7 +456,7 @@ static inline unsigned long hpt_hash(unsigned long vpn,
 
 long hpte_insert_repeating(unsigned long hash, unsigned long vpn, unsigned long pa,
                           unsigned long rlags, unsigned long vflags, int psize, int ssize);
-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 464f8ca..f7827e9 100644 (file)
--- 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/exceptions-64e.S b/arch/powerpc/kernel/exceptions-64e.S
index 74d07dc..43e71d8 100644 (file)
--- 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 91381fb..33f88a1 100644 (file)
--- 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 a1ae006..3c5577a 100644 (file)
--- 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 52702f3..0b2c247 100644 (file)
--- 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 0c4fcb6..61f862f 100644 (file)
--- a/arch/powerpc/kernel/head_book3s_32.S
+++ b/arch/powerpc/kernel/head_book3s_32.S
@@ -362,9 +362,9 @@ BEGIN_MMU_FTR_SECTION
 END_MMU_FTR_SECTION_IFSET(MMU_FTR_HPTE_TABLE)
 #endif
 #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 */
@@ -686,7 +686,6 @@ 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 74e230c..0fbdacc 100644 (file)
--- a/arch/powerpc/kernel/head_booke.h
+++ b/arch/powerpc/kernel/head_booke.h
@@ -476,9 +476,7 @@ label:
        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 e866cae..9a499af 100644 (file)
--- 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 5845679..985902c 100644 (file)
--- 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 8961b44..273ff84 100644 (file)
--- a/arch/powerpc/mm/fault.c
+++ b/arch/powerpc/mm/fault.c
@@ -542,12 +542,11 @@ retry:
 }
 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;