[PATCH 13/7] loongson: Implement the new page table range API

Matthew Wilcox (Oracle)
2023-02-15T00:05:28Z

Add set_ptes() and update_mmu_cache_range().

THIS PATCH IS INCOMPLETE. I DO NOT KNOW WHAT TO DO IN __update_tlb()

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
---
arch/loongarch/include/asm/cacheflush.h | 2 ++
arch/loongarch/include/asm/pgtable.h | 30 ++++++++++++++++---------
arch/loongarch/mm/tlb.c | 4 +++-
3 files changed, 25 insertions(+), 11 deletions(-)

diff --git a/arch/loongarch/include/asm/cacheflush.h b/arch/loongarch/include/asm/cacheflush.h
index 0681788eb474..7907eb42bfbd 100644
--- a/arch/loongarch/include/asm/cacheflush.h
+++ b/arch/loongarch/include/asm/cacheflush.h
@@ -47,8 +47,10 @@ void local_flush_icache_range(unsigned long start, unsigned long end);
#define flush_cache_vmap(start, end) do { } while (0)
#define flush_cache_vunmap(start, end) do { } while (0)
#define flush_icache_page(vma, page) do { } while (0)
+#define flush_icache_pages(vma, page) do { } while (0)
#define flush_icache_user_page(vma, page, addr, len) do { } while (0)
#define flush_dcache_page(page) do { } while (0)
+#define flush_dcache_folio(folio) do { } while (0)
#define flush_dcache_mmap_lock(mapping) do { } while (0)
#define flush_dcache_mmap_unlock(mapping) do { } while (0)

diff --git a/arch/loongarch/include/asm/pgtable.h b/arch/loongarch/include/asm/pgtable.h
index d28fb9dbec59..0f5fa7c40c52 100644
--- a/arch/loongarch/include/asm/pgtable.h
+++ b/arch/loongarch/include/asm/pgtable.h
@@ -334,12 +334,20 @@ static inline void set_pte(pte_t *ptep, pte_t pteval)
}
}

-static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
- pte_t *ptep, pte_t pteval)
-{
- set_pte(ptep, pteval);
+static inline void set_ptes(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep, pte_t pte, unsigned int nr)
+{
+ for (;;) {
+ set_pte(ptep, pte);
+ if (--nr == 0)
+ break;
+ ptep++;
+ pte_val(pte) += 1 << _PFN_SHIFT;
+ }
}

+#define set_pte_at(mm, addr, ptep, pte) set_ptes(mm, addr, ptep, pte, 1)
+
static inline void pte_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
{
/* Preserve global status for the pair */
@@ -442,14 +450,16 @@ static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
(pgprot_val(newprot) & ~_PAGE_CHG_MASK));
}

-extern void __update_tlb(struct vm_area_struct *vma,
- unsigned long address, pte_t *ptep);
+extern void __update_tlb(struct vm_area_struct *vma, unsigned long address,
+ pte_t *ptep, unsigned int nr);

-static inline void update_mmu_cache(struct vm_area_struct *vma,
- unsigned long address, pte_t *ptep)
+static inline void update_mmu_cache_range(struct vm_area_struct *vma,
+ unsigned long address, pte_t *ptep, unsigned int nr)
{
- __update_tlb(vma, address, ptep);
+ __update_tlb(vma, address, ptep, nr);
}
+#define update_mmu_cache(vma, addr, ptep) \
+ update_mmu_cache_range(vma, addr, ptep, 1)

#define __HAVE_ARCH_UPDATE_MMU_TLB
#define update_mmu_tlb update_mmu_cache
@@ -457,7 +467,7 @@ static inline void update_mmu_cache(struct vm_area_struct *vma,
static inline void update_mmu_cache_pmd(struct vm_area_struct *vma,
unsigned long address, pmd_t *pmdp)
{
- __update_tlb(vma, address, (pte_t *)pmdp);
+ __update_tlb(vma, address, (pte_t *)pmdp, 1);
}

static inline unsigned long pmd_pfn(pmd_t pmd)
diff --git a/arch/loongarch/mm/tlb.c b/arch/loongarch/mm/tlb.c
index 8bad6b0cff59..ac0b19dbd1dc 100644
--- a/arch/loongarch/mm/tlb.c
+++ b/arch/loongarch/mm/tlb.c
@@ -162,7 +162,8 @@ static void __update_hugetlb(struct vm_area_struct *vma, unsigned long address,
#endif
}

-void __update_tlb(struct vm_area_struct *vma, unsigned long address, pte_t *ptep)
+void __update_tlb(struct vm_area_struct *vma, unsigned long address,
+ pte_t *ptep, unsigned int nr)
{
int idx;
unsigned long flags;
@@ -187,6 +188,7 @@ void __update_tlb(struct vm_area_struct *vma, unsigned long address, pte_t *ptep
write_csr_entryhi(address);
tlb_probe();
idx = read_csr_tlbidx();
+// I have no idea what to do here
write_csr_pagesize(PS_DEFAULT_SIZE);
write_csr_entrylo0(pte_val(*ptep++));
write_csr_entrylo1(pte_val(*ptep));
--
2.39.1