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powerpc/603: don't handle PAGE_ACCESSED in TLB miss handlers. 

PAGE_ACCESSED is only needed for CONFIG_SWAP. When CONFIG_SWAP
is not set, just ignore it. If CONFIG_SWAP is set and PAGE_ACCESSED
is not, let's take a minor fault.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
hifive-unleashed-5.1
Christophe Leroy 2019-02-21 10:38:02 +00:00 committed by Michael Ellerman
parent 451b3ec082
commit 84de6ab0e9
1 changed files with 13 additions and 11 deletions
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24
arch/powerpc/kernel/head_32.S
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@ -503,7 +503,11 @@ InstructionTLBMiss:
cmplw 0,r1,r3
#endif
mfspr r2, SPRN_SPRG_PGDIR
#ifdef CONFIG_SWAP
li r1,_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_EXEC
#else
li r1,_PAGE_PRESENT | _PAGE_EXEC
#endif
#if defined(CONFIG_MODULES) || defined(CONFIG_DEBUG_PAGEALLOC)
bge- 112f
lis r2, (swapper_pg_dir - PAGE_OFFSET)@ha /* if kernel address, use */
@ -517,12 +521,6 @@ InstructionTLBMiss:
lwz r0,0(r2) /* get linux-style pte */
andc. r1,r1,r0 /* check access & ~permission */
bne- InstructionAddressInvalid /* return if access not permitted */
ori r0,r0,_PAGE_ACCESSED /* set _PAGE_ACCESSED in pte */
/*
* NOTE! We are assuming this is not an SMP system, otherwise
* we would need to update the pte atomically with lwarx/stwcx.
*/
stw r0,0(r2) /* update PTE (accessed bit) */
/* Convert linux-style PTE to low word of PPC-style PTE */
rlwimi r0,r0,32-1,30,30 /* _PAGE_USER -> PP msb */
ori r1, r1, 0xe05 /* clear out reserved bits */
@ -571,7 +569,11 @@ DataLoadTLBMiss:
lis r1,PAGE_OFFSET@h /* check if kernel address */
cmplw 0,r1,r3
mfspr r2, SPRN_SPRG_PGDIR
#ifdef CONFIG_SWAP
li r1, _PAGE_PRESENT | _PAGE_ACCESSED
#else
li r1, _PAGE_PRESENT
#endif
bge- 112f
lis r2, (swapper_pg_dir - PAGE_OFFSET)@ha /* if kernel address, use */
addi r2, r2, (swapper_pg_dir - PAGE_OFFSET)@l /* kernel page table */
@ -583,12 +585,10 @@ DataLoadTLBMiss:
lwz r0,0(r2) /* get linux-style pte */
andc. r1,r1,r0 /* check access & ~permission */
bne- DataAddressInvalid /* return if access not permitted */
ori r0,r0,_PAGE_ACCESSED /* set _PAGE_ACCESSED in pte */
/*
* NOTE! We are assuming this is not an SMP system, otherwise
* we would need to update the pte atomically with lwarx/stwcx.
*/
stw r0,0(r2) /* update PTE (accessed bit) */
/* Convert linux-style PTE to low word of PPC-style PTE */
rlwinm r1,r0,32-10,31,31 /* _PAGE_RW -> PP lsb */
rlwimi r0,r0,32-1,30,30 /* _PAGE_USER -> PP msb */
@ -649,7 +649,11 @@ DataStoreTLBMiss:
lis r1,PAGE_OFFSET@h /* check if kernel address */
cmplw 0,r1,r3
mfspr r2, SPRN_SPRG_PGDIR
li r1, _PAGE_RW | _PAGE_PRESENT /* access flags */
#ifdef CONFIG_SWAP
li r1, _PAGE_RW | _PAGE_PRESENT | _PAGE_ACCESSED
#else
li r1, _PAGE_RW | _PAGE_PRESENT
#endif
bge- 112f
lis r2, (swapper_pg_dir - PAGE_OFFSET)@ha /* if kernel address, use */
addi r2, r2, (swapper_pg_dir - PAGE_OFFSET)@l /* kernel page table */
@ -661,12 +665,10 @@ DataStoreTLBMiss:
lwz r0,0(r2) /* get linux-style pte */
andc. r1,r1,r0 /* check access & ~permission */
bne- DataAddressInvalid /* return if access not permitted */
ori r0,r0,_PAGE_ACCESSED
/*
* NOTE! We are assuming this is not an SMP system, otherwise
* we would need to update the pte atomically with lwarx/stwcx.
*/
stw r0,0(r2) /* update PTE (accessed/dirty bits) */
/* Convert linux-style PTE to low word of PPC-style PTE */
rlwimi r0,r0,32-1,30,30 /* _PAGE_USER -> PP msb */
li r1,0xe05 /* clear out reserved bits & PP lsb */