powerpc/64s/hash: remove user SLB data from the paca

User SLB mappig data is copied into the PACA from the mm->context so
it can be accessed by the SLB miss handlers.

After the C conversion, SLB miss handlers now run with relocation on,
and user SLB misses are able to take recursive kernel SLB misses, so
the user SLB mapping data can be removed from the paca and accessed
directly.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

1 files changed, 11 insertions, 35 deletions

diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c
index f23a89d8e4ce6..88c95dc8b141f 100644
--- a/arch/powerpc/mm/hash_utils_64.c
+++ b/arch/powerpc/mm/hash_utils_64.c
@@ -1088,16 +1088,16 @@ unsigned int hash_page_do_lazy_icache(unsigned int pp, pte_t pte, int trap)
 }
 
 #ifdef CONFIG_PPC_MM_SLICES
-static unsigned int get_paca_psize(unsigned long addr)
+static unsigned int get_psize(struct mm_struct *mm, unsigned long addr)
 {
 	unsigned char *psizes;
 	unsigned long index, mask_index;
 
 	if (addr < SLICE_LOW_TOP) {
-		psizes = get_paca()->mm_ctx_low_slices_psize;
+		psizes = mm->context.low_slices_psize;
 		index = GET_LOW_SLICE_INDEX(addr);
 	} else {
-		psizes = get_paca()->mm_ctx_high_slices_psize;
+		psizes = mm->context.high_slices_psize;
 		index = GET_HIGH_SLICE_INDEX(addr);
 	}
 	mask_index = index & 0x1;
@@ -1105,9 +1105,9 @@ static unsigned int get_paca_psize(unsigned long addr)
 }
 
 #else
-unsigned int get_paca_psize(unsigned long addr)
+unsigned int get_psize(struct mm_struct *mm, unsigned long addr)
 {
-	return get_paca()->mm_ctx_user_psize;
+	return mm->context.user_psize;
 }
 #endif
 
@@ -1118,15 +1118,11 @@ unsigned int get_paca_psize(unsigned long addr)
 #ifdef CONFIG_PPC_64K_PAGES
 void demote_segment_4k(struct mm_struct *mm, unsigned long addr)
 {
-	if (get_slice_psize(mm, addr) == MMU_PAGE_4K)
+	if (get_psize(mm, addr) == MMU_PAGE_4K)
 		return;
 	slice_set_range_psize(mm, addr, 1, MMU_PAGE_4K);
 	copro_flush_all_slbs(mm);
-	if ((get_paca_psize(addr) != MMU_PAGE_4K) && (current->mm == mm)) {
-
-		copy_mm_to_paca(mm);
-		slb_flush_and_rebolt();
-	}
+	core_flush_all_slbs(mm);
 }
 #endif /* CONFIG_PPC_64K_PAGES */
 
@@ -1191,22 +1187,6 @@ void hash_failure_debug(unsigned long ea, unsigned long access,
 		trap, vsid, ssize, psize, lpsize, pte);
 }
 
-static void check_paca_psize(unsigned long ea, struct mm_struct *mm,
-			     int psize, bool user_region)
-{
-	if (user_region) {
-		if (psize != get_paca_psize(ea)) {
-			copy_mm_to_paca(mm);
-			slb_flush_and_rebolt();
-		}
-	} else if (get_paca()->vmalloc_sllp !=
-		   mmu_psize_defs[mmu_vmalloc_psize].sllp) {
-		get_paca()->vmalloc_sllp =
-			mmu_psize_defs[mmu_vmalloc_psize].sllp;
-		slb_vmalloc_update();
-	}
-}
-
 /* Result code is:
  *  0 - handled
  *  1 - normal page fault
@@ -1239,7 +1219,7 @@ int hash_page_mm(struct mm_struct *mm, unsigned long ea,
 			rc = 1;
 			goto bail;
 		}
-		psize = get_slice_psize(mm, ea);
+		psize = get_psize(mm, ea);
 		ssize = user_segment_size(ea);
 		vsid = get_user_vsid(&mm->context, ea, ssize);
 		break;
@@ -1327,9 +1307,6 @@ int hash_page_mm(struct mm_struct *mm, unsigned long ea,
 			WARN_ON(1);
 		}
 #endif
-		if (current->mm == mm)
-			check_paca_psize(ea, mm, psize, user_region);
-
 		goto bail;
 	}
 
@@ -1364,15 +1341,14 @@ int hash_page_mm(struct mm_struct *mm, unsigned long ea,
 			       "to 4kB pages because of "
 			       "non-cacheable mapping\n");
 			psize = mmu_vmalloc_psize = MMU_PAGE_4K;
+			slb_vmalloc_update();
 			copro_flush_all_slbs(mm);
+			core_flush_all_slbs(mm);
 		}
 	}
 
 #endif /* CONFIG_PPC_64K_PAGES */
 
-	if (current->mm == mm)
-		check_paca_psize(ea, mm, psize, user_region);
-
 #ifdef CONFIG_PPC_64K_PAGES
 	if (psize == MMU_PAGE_64K)
 		rc = __hash_page_64K(ea, access, vsid, ptep, trap,
@@ -1460,7 +1436,7 @@ int __hash_page(unsigned long ea, unsigned long msr, unsigned long trap,
 #ifdef CONFIG_PPC_MM_SLICES
 static bool should_hash_preload(struct mm_struct *mm, unsigned long ea)
 {
-	int psize = get_slice_psize(mm, ea);
+	int psize = get_psize(mm, ea);
 
 	/* We only prefault standard pages for now */
 	if (unlikely(psize != mm->context.user_psize))