| Message ID | 20201027171944.13933-5-alexandru.elisei@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | arm64: Statistical Profiling Extension Tests | expand |
Hi Alexandru, On 10/27/20 6:19 PM, Alexandru Elisei wrote: > Being able to cause a stage 1 data abort might be useful for future tests. > Add a function that unmaps a page from the translation tables. > > Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com> > --- > lib/arm/asm/mmu-api.h | 1 + > lib/arm/mmu.c | 32 ++++++++++++++++++++++++++++++++ > 2 files changed, 33 insertions(+) > > diff --git a/lib/arm/asm/mmu-api.h b/lib/arm/asm/mmu-api.h > index 2bbe1faea900..305f77c6501f 100644 > --- a/lib/arm/asm/mmu-api.h > +++ b/lib/arm/asm/mmu-api.h > @@ -23,4 +23,5 @@ extern void mmu_set_range_ptes(pgd_t *pgtable, uintptr_t virt_offset, > phys_addr_t phys_start, phys_addr_t phys_end, > pgprot_t prot); > extern void mmu_clear_user(pgd_t *pgtable, unsigned long vaddr); > +extern void mmu_unmap_page(pgd_t *pgtable, unsigned long vaddr); > #endif > diff --git a/lib/arm/mmu.c b/lib/arm/mmu.c > index 540a1e842d5b..72ac0be8d146 100644 > --- a/lib/arm/mmu.c > +++ b/lib/arm/mmu.c > @@ -232,3 +232,35 @@ void mmu_clear_user(pgd_t *pgtable, unsigned long vaddr) > out_flush_tlb: > flush_tlb_page(vaddr); > } > + > +void mmu_unmap_page(pgd_t *pgtable, unsigned long vaddr) > +{ > + pgd_t *pgd; > + pmd_t *pmd; > + pte_t *pte; > + > + if (!mmu_enabled()) > + return; > + > + pgd = pgd_offset(pgtable, vaddr); > + if (!pgd_valid(*pgd)) > + return; > + > + pmd = pmd_offset(pgd, vaddr); > + if (!pmd_valid(*pmd)) > + return; > + > + if (pmd_huge(*pmd)) { > + WRITE_ONCE(*pmd, 0); > + goto out_flush_tlb; > + } else { is the else needed? > + pte = pte_offset(pmd, vaddr); > + if (!pte_valid(*pte)) > + return; > + WRITE_ONCE(*pte, 0); > + goto out_flush_tlb; > + } > + > +out_flush_tlb: > + flush_tlb_page(vaddr); > +} > This code is very similar to mmu_clear_user() besides the bit to invalidate Just wondering if we couldn't use the same code and pass a bit offset. It seems the offsets in PMD and PTE are same for USER bit and valid bit. But maybe this is far-fetched and not worth the sharing. I see Drew is not in CC, + Drew Besides Reviewed-by: Eric Auger <eric.auger@redhat.com> Thanks Eric
Hi Eric, On 10/30/20 3:46 PM, Auger Eric wrote: > Hi Alexandru, > > On 10/27/20 6:19 PM, Alexandru Elisei wrote: >> Being able to cause a stage 1 data abort might be useful for future tests. >> Add a function that unmaps a page from the translation tables. >> >> Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com> >> --- >> lib/arm/asm/mmu-api.h | 1 + >> lib/arm/mmu.c | 32 ++++++++++++++++++++++++++++++++ >> 2 files changed, 33 insertions(+) >> >> diff --git a/lib/arm/asm/mmu-api.h b/lib/arm/asm/mmu-api.h >> index 2bbe1faea900..305f77c6501f 100644 >> --- a/lib/arm/asm/mmu-api.h >> +++ b/lib/arm/asm/mmu-api.h >> @@ -23,4 +23,5 @@ extern void mmu_set_range_ptes(pgd_t *pgtable, uintptr_t virt_offset, >> phys_addr_t phys_start, phys_addr_t phys_end, >> pgprot_t prot); >> extern void mmu_clear_user(pgd_t *pgtable, unsigned long vaddr); >> +extern void mmu_unmap_page(pgd_t *pgtable, unsigned long vaddr); >> #endif >> diff --git a/lib/arm/mmu.c b/lib/arm/mmu.c >> index 540a1e842d5b..72ac0be8d146 100644 >> --- a/lib/arm/mmu.c >> +++ b/lib/arm/mmu.c >> @@ -232,3 +232,35 @@ void mmu_clear_user(pgd_t *pgtable, unsigned long vaddr) >> out_flush_tlb: >> flush_tlb_page(vaddr); >> } >> + >> +void mmu_unmap_page(pgd_t *pgtable, unsigned long vaddr) >> +{ >> + pgd_t *pgd; >> + pmd_t *pmd; >> + pte_t *pte; >> + >> + if (!mmu_enabled()) >> + return; >> + >> + pgd = pgd_offset(pgtable, vaddr); >> + if (!pgd_valid(*pgd)) >> + return; >> + >> + pmd = pmd_offset(pgd, vaddr); >> + if (!pmd_valid(*pmd)) >> + return; >> + >> + if (pmd_huge(*pmd)) { >> + WRITE_ONCE(*pmd, 0); >> + goto out_flush_tlb; >> + } else { > is the else needed? No, not needed. Will remove. >> + pte = pte_offset(pmd, vaddr); >> + if (!pte_valid(*pte)) >> + return; >> + WRITE_ONCE(*pte, 0); >> + goto out_flush_tlb; >> + } >> + >> +out_flush_tlb: >> + flush_tlb_page(vaddr); >> +} >> > This code is very similar to mmu_clear_user() besides the bit to invalidate > Just wondering if we couldn't use the same code and pass a bit offset. > It seems the offsets in PMD and PTE are same for USER bit and valid bit. Yes, I will look into it and see what I can come up with. > > But maybe this is far-fetched and not worth the sharing. > I see Drew is not in CC, + Drew Yeah... I somehow missed adding Drew to CC for the entire series. > > Besides > Reviewed-by: Eric Auger <eric.auger@redhat.com> Thanks, Alex > > Thanks > > Eric >
diff --git a/lib/arm/asm/mmu-api.h b/lib/arm/asm/mmu-api.h index 2bbe1faea900..305f77c6501f 100644 --- a/lib/arm/asm/mmu-api.h +++ b/lib/arm/asm/mmu-api.h @@ -23,4 +23,5 @@ extern void mmu_set_range_ptes(pgd_t *pgtable, uintptr_t virt_offset, phys_addr_t phys_start, phys_addr_t phys_end, pgprot_t prot); extern void mmu_clear_user(pgd_t *pgtable, unsigned long vaddr); +extern void mmu_unmap_page(pgd_t *pgtable, unsigned long vaddr); #endif diff --git a/lib/arm/mmu.c b/lib/arm/mmu.c index 540a1e842d5b..72ac0be8d146 100644 --- a/lib/arm/mmu.c +++ b/lib/arm/mmu.c @@ -232,3 +232,35 @@ void mmu_clear_user(pgd_t *pgtable, unsigned long vaddr) out_flush_tlb: flush_tlb_page(vaddr); } + +void mmu_unmap_page(pgd_t *pgtable, unsigned long vaddr) +{ + pgd_t *pgd; + pmd_t *pmd; + pte_t *pte; + + if (!mmu_enabled()) + return; + + pgd = pgd_offset(pgtable, vaddr); + if (!pgd_valid(*pgd)) + return; + + pmd = pmd_offset(pgd, vaddr); + if (!pmd_valid(*pmd)) + return; + + if (pmd_huge(*pmd)) { + WRITE_ONCE(*pmd, 0); + goto out_flush_tlb; + } else { + pte = pte_offset(pmd, vaddr); + if (!pte_valid(*pte)) + return; + WRITE_ONCE(*pte, 0); + goto out_flush_tlb; + } + +out_flush_tlb: + flush_tlb_page(vaddr); +}
Being able to cause a stage 1 data abort might be useful for future tests. Add a function that unmaps a page from the translation tables. Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com> --- lib/arm/asm/mmu-api.h | 1 + lib/arm/mmu.c | 32 ++++++++++++++++++++++++++++++++ 2 files changed, 33 insertions(+)