[PATCH 1/3] powerpc/nohash: remove hash related code from nohash headers.

From: Christophe Leroy
Date: Tue Apr 24 2018 - 12:31:38 EST


When nohash and book3s header were split, some hash related stuff
remained in the nohash header. This patch removes them.

Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxx>
---
arch/powerpc/include/asm/nohash/32/pgtable.h | 29 +++------------------
arch/powerpc/include/asm/nohash/64/pgtable.h | 16 ++----------
arch/powerpc/include/asm/nohash/pgtable.h | 38 +++-------------------------
arch/powerpc/include/asm/nohash/pte-book3e.h | 1 -
4 files changed, 10 insertions(+), 74 deletions(-)

diff --git a/arch/powerpc/include/asm/nohash/32/pgtable.h b/arch/powerpc/include/asm/nohash/32/pgtable.h
index a717b5c39b9c..b413abcd5a09 100644
--- a/arch/powerpc/include/asm/nohash/32/pgtable.h
+++ b/arch/powerpc/include/asm/nohash/32/pgtable.h
@@ -129,7 +129,7 @@ extern int icache_44x_need_flush;
#ifndef __ASSEMBLY__

#define pte_clear(mm, addr, ptep) \
- do { pte_update(ptep, ~_PAGE_HASHPTE, 0); } while (0)
+ do { pte_update(ptep, ~0, 0); } while (0)

#define pmd_none(pmd) (!pmd_val(pmd))
#define pmd_bad(pmd) (pmd_val(pmd) & _PMD_BAD)
@@ -142,21 +142,6 @@ static inline void pmd_clear(pmd_t *pmdp)


/*
- * When flushing the tlb entry for a page, we also need to flush the hash
- * table entry. flush_hash_pages is assembler (for speed) in hashtable.S.
- */
-extern int flush_hash_pages(unsigned context, unsigned long va,
- unsigned long pmdval, int count);
-
-/* Add an HPTE to the hash table */
-extern void add_hash_page(unsigned context, unsigned long va,
- unsigned long pmdval);
-
-/* Flush an entry from the TLB/hash table */
-extern void flush_hash_entry(struct mm_struct *mm, pte_t *ptep,
- unsigned long address);
-
-/*
* PTE updates. This function is called whenever an existing
* valid PTE is updated. This does -not- include set_pte_at()
* which nowadays only sets a new PTE.
@@ -242,12 +227,6 @@ static inline int __ptep_test_and_clear_young(unsigned int context, unsigned lon
{
unsigned long old;
old = pte_update(ptep, _PAGE_ACCESSED, 0);
-#if _PAGE_HASHPTE != 0
- if (old & _PAGE_HASHPTE) {
- unsigned long ptephys = __pa(ptep) & PAGE_MASK;
- flush_hash_pages(context, addr, ptephys, 1);
- }
-#endif
return (old & _PAGE_ACCESSED) != 0;
}
#define ptep_test_and_clear_young(__vma, __addr, __ptep) \
@@ -257,7 +236,7 @@ static inline int __ptep_test_and_clear_young(unsigned int context, unsigned lon
static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
pte_t *ptep)
{
- return __pte(pte_update(ptep, ~_PAGE_HASHPTE, 0));
+ return __pte(pte_update(ptep, ~0, 0));
}

#define __HAVE_ARCH_PTEP_SET_WRPROTECT
@@ -285,7 +264,7 @@ static inline void __ptep_set_access_flags(struct mm_struct *mm,
}

#define __HAVE_ARCH_PTE_SAME
-#define pte_same(A,B) (((pte_val(A) ^ pte_val(B)) & ~_PAGE_HASHPTE) == 0)
+#define pte_same(A,B) ((pte_val(A) ^ pte_val(B)) == 0)

/*
* Note that on Book E processors, the pmd contains the kernel virtual
@@ -326,7 +305,7 @@ static inline void __ptep_set_access_flags(struct mm_struct *mm,
/*
* Encode and decode a swap entry.
* Note that the bits we use in a PTE for representing a swap entry
- * must not include the _PAGE_PRESENT bit or the _PAGE_HASHPTE bit (if used).
+ * must not include the _PAGE_PRESENT bit.
* -- paulus
*/
#define __swp_type(entry) ((entry).val & 0x1f)
diff --git a/arch/powerpc/include/asm/nohash/64/pgtable.h b/arch/powerpc/include/asm/nohash/64/pgtable.h
index 5c5f75d005ad..251d74c9013e 100644
--- a/arch/powerpc/include/asm/nohash/64/pgtable.h
+++ b/arch/powerpc/include/asm/nohash/64/pgtable.h
@@ -173,8 +173,6 @@ static inline void pgd_set(pgd_t *pgdp, unsigned long val)
/* to find an entry in a kernel page-table-directory */
/* This now only contains the vmalloc pages */
#define pgd_offset_k(address) pgd_offset(&init_mm, address)
-extern void hpte_need_flush(struct mm_struct *mm, unsigned long addr,
- pte_t *ptep, unsigned long pte, int huge);

/* Atomic PTE updates */
static inline unsigned long pte_update(struct mm_struct *mm,
@@ -205,11 +203,6 @@ static inline unsigned long pte_update(struct mm_struct *mm,
if (!huge)
assert_pte_locked(mm, addr);

-#ifdef CONFIG_PPC_BOOK3S_64
- if (old & _PAGE_HASHPTE)
- hpte_need_flush(mm, addr, ptep, old, huge);
-#endif
-
return old;
}

@@ -218,7 +211,7 @@ static inline int __ptep_test_and_clear_young(struct mm_struct *mm,
{
unsigned long old;

- if ((pte_val(*ptep) & (_PAGE_ACCESSED | _PAGE_HASHPTE)) == 0)
+ if (pte_young(*ptep))
return 0;
old = pte_update(mm, addr, ptep, _PAGE_ACCESSED, 0, 0);
return (old & _PAGE_ACCESSED) != 0;
@@ -312,7 +305,7 @@ static inline void __ptep_set_access_flags(struct mm_struct *mm,
}

#define __HAVE_ARCH_PTE_SAME
-#define pte_same(A,B) (((pte_val(A) ^ pte_val(B)) & ~_PAGE_HPTEFLAGS) == 0)
+#define pte_same(A,B) ((pte_val(A) ^ pte_val(B)) == 0)

#define pte_ERROR(e) \
pr_err("%s:%d: bad pte %08lx.\n", __FILE__, __LINE__, pte_val(e))
@@ -324,11 +317,6 @@ static inline void __ptep_set_access_flags(struct mm_struct *mm,
/* Encode and de-code a swap entry */
#define MAX_SWAPFILES_CHECK() do { \
BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > SWP_TYPE_BITS); \
- /* \
- * Don't have overlapping bits with _PAGE_HPTEFLAGS \
- * We filter HPTEFLAGS on set_pte. \
- */ \
- BUILD_BUG_ON(_PAGE_HPTEFLAGS & (0x1f << _PAGE_BIT_SWAP_TYPE)); \
} while (0)
/*
* on pte we don't need handle RADIX_TREE_EXCEPTIONAL_SHIFT;
diff --git a/arch/powerpc/include/asm/nohash/pgtable.h b/arch/powerpc/include/asm/nohash/pgtable.h
index c56de1e8026f..f2fe3cbe90af 100644
--- a/arch/powerpc/include/asm/nohash/pgtable.h
+++ b/arch/powerpc/include/asm/nohash/pgtable.h
@@ -148,37 +148,16 @@ extern void set_pte_at(struct mm_struct *mm, unsigned long addr, pte_t *ptep,
static inline void __set_pte_at(struct mm_struct *mm, unsigned long addr,
pte_t *ptep, pte_t pte, int percpu)
{
-#if defined(CONFIG_PPC_STD_MMU_32) && defined(CONFIG_SMP) && !defined(CONFIG_PTE_64BIT)
- /* First case is 32-bit Hash MMU in SMP mode with 32-bit PTEs. We use the
- * helper pte_update() which does an atomic update. We need to do that
- * because a concurrent invalidation can clear _PAGE_HASHPTE. If it's a
- * per-CPU PTE such as a kmap_atomic, we do a simple update preserving
- * the hash bits instead (ie, same as the non-SMP case)
- */
- if (percpu)
- *ptep = __pte((pte_val(*ptep) & _PAGE_HASHPTE)
- | (pte_val(pte) & ~_PAGE_HASHPTE));
- else
- pte_update(ptep, ~_PAGE_HASHPTE, pte_val(pte));
-
-#elif defined(CONFIG_PPC32) && defined(CONFIG_PTE_64BIT)
+#if defined(CONFIG_PPC32) && defined(CONFIG_PTE_64BIT)
/* Second case is 32-bit with 64-bit PTE. In this case, we
* can just store as long as we do the two halves in the right order
- * with a barrier in between. This is possible because we take care,
- * in the hash code, to pre-invalidate if the PTE was already hashed,
- * which synchronizes us with any concurrent invalidation.
- * In the percpu case, we also fallback to the simple update preserving
- * the hash bits
+ * with a barrier in between.
+ * In the percpu case, we also fallback to the simple update
*/
if (percpu) {
- *ptep = __pte((pte_val(*ptep) & _PAGE_HASHPTE)
- | (pte_val(pte) & ~_PAGE_HASHPTE));
+ *ptep = pte;
return;
}
-#if _PAGE_HASHPTE != 0
- if (pte_val(*ptep) & _PAGE_HASHPTE)
- flush_hash_entry(mm, ptep, addr);
-#endif
__asm__ __volatile__("\
stw%U0%X0 %2,%0\n\
eieio\n\
@@ -186,15 +165,6 @@ static inline void __set_pte_at(struct mm_struct *mm, unsigned long addr,
: "=m" (*ptep), "=m" (*((unsigned char *)ptep+4))
: "r" (pte) : "memory");

-#elif defined(CONFIG_PPC_STD_MMU_32)
- /* Third case is 32-bit hash table in UP mode, we need to preserve
- * the _PAGE_HASHPTE bit since we may not have invalidated the previous
- * translation in the hash yet (done in a subsequent flush_tlb_xxx())
- * and see we need to keep track that this PTE needs invalidating
- */
- *ptep = __pte((pte_val(*ptep) & _PAGE_HASHPTE)
- | (pte_val(pte) & ~_PAGE_HASHPTE));
-
#else
/* Anything else just stores the PTE normally. That covers all 64-bit
* cases, and 32-bit non-hash with 32-bit PTEs.
diff --git a/arch/powerpc/include/asm/nohash/pte-book3e.h b/arch/powerpc/include/asm/nohash/pte-book3e.h
index ccee8eb509bb..9ff51b4c0cac 100644
--- a/arch/powerpc/include/asm/nohash/pte-book3e.h
+++ b/arch/powerpc/include/asm/nohash/pte-book3e.h
@@ -57,7 +57,6 @@
#define _PAGE_USER (_PAGE_BAP_UR | _PAGE_BAP_SR) /* Can be read */
#define _PAGE_PRIVILEGED (_PAGE_BAP_SR)

-#define _PAGE_HASHPTE 0
#define _PAGE_BUSY 0

#define _PAGE_SPECIAL _PAGE_SW0
--
2.13.3