1 files changed, 114 insertions, 181 deletions

diff --git a/arch/powerpc/mm/nohash/8xx.c b/arch/powerpc/mm/nohash/8xx.c
index 090af2d2d3e4..6be6421086ed 100644
--- a/arch/powerpc/mm/nohash/8xx.c
+++ b/arch/powerpc/mm/nohash/8xx.c
@@ -8,28 +8,24 @@
  */
 
 #include <linux/memblock.h>
-#include <linux/mmu_context.h>
+#include <linux/hugetlb.h>
+
 #include <asm/fixmap.h>
-#include <asm/code-patching.h>
 
 #include <mm/mmu_decl.h>
 
 #define IMMR_SIZE (FIX_IMMR_SIZE << PAGE_SHIFT)
 
-extern int __map_without_ltlbs;
-
 static unsigned long block_mapped_ram;
 
 /*
- * Return PA for this VA if it is in an area mapped with LTLBs.
+ * Return PA for this VA if it is in an area mapped with LTLBs or fixmap.
  * Otherwise, returns 0
  */
 phys_addr_t v_block_mapped(unsigned long va)
 {
 	unsigned long p = PHYS_IMMR_BASE;
 
-	if (__map_without_ltlbs)
-		return 0;
 	if (va >= VIRT_IMMR_BASE && va < VIRT_IMMR_BASE + IMMR_SIZE)
 		return p + va - VIRT_IMMR_BASE;
 	if (va >= PAGE_OFFSET && va < PAGE_OFFSET + block_mapped_ram)
@@ -38,14 +34,13 @@ phys_addr_t v_block_mapped(unsigned long va)
 }
 
 /*
- * Return VA for a given PA mapped with LTLBs or 0 if not mapped
+ * Return VA for a given PA mapped with LTLBs or fixmap
+ * Return 0 if not mapped
  */
 unsigned long p_block_mapped(phys_addr_t pa)
 {
 	unsigned long p = PHYS_IMMR_BASE;
 
-	if (__map_without_ltlbs)
-		return 0;
 	if (pa >= p && pa < p + IMMR_SIZE)
 		return VIRT_IMMR_BASE + pa - p;
 	if (pa < block_mapped_ram)
@@ -53,155 +48,145 @@ unsigned long p_block_mapped(phys_addr_t pa)
 	return 0;
 }
 
-#define LARGE_PAGE_SIZE_8M	(1<<23)
-
-/*
- * MMU_init_hw does the chip-specific initialization of the MMU hardware.
- */
-void __init MMU_init_hw(void)
+static pte_t __init *early_hugepd_alloc_kernel(hugepd_t *pmdp, unsigned long va)
 {
-	/* PIN up to the 3 first 8Mb after IMMR in DTLB table */
-	if (IS_ENABLED(CONFIG_PIN_TLB_DATA)) {
-		unsigned long ctr = mfspr(SPRN_MD_CTR) & 0xfe000000;
-		unsigned long flags = 0xf0 | MD_SPS16K | _PAGE_SH | _PAGE_DIRTY;
-		int i = IS_ENABLED(CONFIG_PIN_TLB_IMMR) ? 29 : 28;
-		unsigned long addr = 0;
-		unsigned long mem = total_lowmem;
-
-		for (; i < 32 && mem >= LARGE_PAGE_SIZE_8M; i++) {
-			mtspr(SPRN_MD_CTR, ctr | (i << 8));
-			mtspr(SPRN_MD_EPN, (unsigned long)__va(addr) | MD_EVALID);
-			mtspr(SPRN_MD_TWC, MD_PS8MEG | MD_SVALID);
-			mtspr(SPRN_MD_RPN, addr | flags | _PAGE_PRESENT);
-			addr += LARGE_PAGE_SIZE_8M;
-			mem -= LARGE_PAGE_SIZE_8M;
-		}
+	if (hpd_val(*pmdp) == 0) {
+		pte_t *ptep = memblock_alloc(sizeof(pte_basic_t), SZ_4K);
+
+		if (!ptep)
+			return NULL;
+
+		hugepd_populate_kernel((hugepd_t *)pmdp, ptep, PAGE_SHIFT_8M);
+		hugepd_populate_kernel((hugepd_t *)pmdp + 1, ptep, PAGE_SHIFT_8M);
 	}
+	return hugepte_offset(*(hugepd_t *)pmdp, va, PGDIR_SHIFT);
 }
 
-static void __init mmu_mapin_immr(void)
+static int __ref __early_map_kernel_hugepage(unsigned long va, phys_addr_t pa,
+					     pgprot_t prot, int psize, bool new)
 {
-	unsigned long p = PHYS_IMMR_BASE;
-	unsigned long v = VIRT_IMMR_BASE;
-	int offset;
+	pmd_t *pmdp = pmd_off_k(va);
+	pte_t *ptep;
+
+	if (WARN_ON(psize != MMU_PAGE_512K && psize != MMU_PAGE_8M))
+		return -EINVAL;
+
+	if (new) {
+		if (WARN_ON(slab_is_available()))
+			return -EINVAL;
+
+		if (psize == MMU_PAGE_512K)
+			ptep = early_pte_alloc_kernel(pmdp, va);
+		else
+			ptep = early_hugepd_alloc_kernel((hugepd_t *)pmdp, va);
+	} else {
+		if (psize == MMU_PAGE_512K)
+			ptep = pte_offset_kernel(pmdp, va);
+		else
+			ptep = hugepte_offset(*(hugepd_t *)pmdp, va, PGDIR_SHIFT);
+	}
+
+	if (WARN_ON(!ptep))
+		return -ENOMEM;
 
-	for (offset = 0; offset < IMMR_SIZE; offset += PAGE_SIZE)
-		map_kernel_page(v + offset, p + offset, PAGE_KERNEL_NCG);
+	/* The PTE should never be already present */
+	if (new && WARN_ON(pte_present(*ptep) && pgprot_val(prot)))
+		return -EINVAL;
+
+	set_huge_pte_at(&init_mm, va, ptep,
+			pte_mkhuge(pfn_pte(pa >> PAGE_SHIFT, prot)), psize);
+
+	return 0;
 }
 
-static void mmu_patch_cmp_limit(s32 *site, unsigned long mapped)
+/*
+ * MMU_init_hw does the chip-specific initialization of the MMU hardware.
+ */
+void __init MMU_init_hw(void)
 {
-	modify_instruction_site(site, 0xffff, (unsigned long)__va(mapped) >> 16);
 }
 
-static void mmu_patch_addis(s32 *site, long simm)
+static bool immr_is_mapped __initdata;
+
+void __init mmu_mapin_immr(void)
 {
-	unsigned int instr = *(unsigned int *)patch_site_addr(site);
+	if (immr_is_mapped)
+		return;
+
+	immr_is_mapped = true;
 
-	instr &= 0xffff0000;
-	instr |= ((unsigned long)simm) >> 16;
-	patch_instruction_site(site, instr);
+	__early_map_kernel_hugepage(VIRT_IMMR_BASE, PHYS_IMMR_BASE,
+				    PAGE_KERNEL_NCG, MMU_PAGE_512K, true);
 }
 
-void __init mmu_mapin_ram_chunk(unsigned long offset, unsigned long top, pgprot_t prot)
+static void mmu_mapin_ram_chunk(unsigned long offset, unsigned long top,
+				pgprot_t prot, bool new)
 {
-	unsigned long s = offset;
-	unsigned long v = PAGE_OFFSET + s;
-	phys_addr_t p = memstart_addr + s;
-
-	for (; s < top; s += PAGE_SIZE) {
-		map_kernel_page(v, p, prot);
-		v += PAGE_SIZE;
-		p += PAGE_SIZE;
-	}
+	unsigned long v = PAGE_OFFSET + offset;
+	unsigned long p = offset;
+
+	WARN_ON(!IS_ALIGNED(offset, SZ_512K) || !IS_ALIGNED(top, SZ_512K));
+
+	for (; p < ALIGN(p, SZ_8M) && p < top; p += SZ_512K, v += SZ_512K)
+		__early_map_kernel_hugepage(v, p, prot, MMU_PAGE_512K, new);
+	for (; p < ALIGN_DOWN(top, SZ_8M) && p < top; p += SZ_8M, v += SZ_8M)
+		__early_map_kernel_hugepage(v, p, prot, MMU_PAGE_8M, new);
+	for (; p < ALIGN_DOWN(top, SZ_512K) && p < top; p += SZ_512K, v += SZ_512K)
+		__early_map_kernel_hugepage(v, p, prot, MMU_PAGE_512K, new);
+
+	if (!new)
+		flush_tlb_kernel_range(PAGE_OFFSET + v, PAGE_OFFSET + top);
 }
 
 unsigned long __init mmu_mapin_ram(unsigned long base, unsigned long top)
 {
-	unsigned long mapped;
-
-	if (__map_without_ltlbs) {
-		mapped = 0;
-		mmu_mapin_immr();
-		if (!IS_ENABLED(CONFIG_PIN_TLB_IMMR))
-			patch_instruction_site(&patch__dtlbmiss_immr_jmp, PPC_INST_NOP);
-		if (!IS_ENABLED(CONFIG_PIN_TLB_TEXT))
-			mmu_patch_cmp_limit(&patch__itlbmiss_linmem_top, 0);
+	unsigned long etext8 = ALIGN(__pa(_etext), SZ_8M);
+	unsigned long sinittext = __pa(_sinittext);
+	bool strict_boundary = strict_kernel_rwx_enabled() || debug_pagealloc_enabled_or_kfence();
+	unsigned long boundary = strict_boundary ? sinittext : etext8;
+	unsigned long einittext8 = ALIGN(__pa(_einittext), SZ_8M);
+
+	WARN_ON(top < einittext8);
+
+	mmu_mapin_immr();
+
+	mmu_mapin_ram_chunk(0, boundary, PAGE_KERNEL_TEXT, true);
+	if (debug_pagealloc_enabled_or_kfence()) {
+		top = boundary;
 	} else {
-		unsigned long einittext8 = ALIGN(__pa(_einittext), SZ_8M);
-
-		mapped = top & ~(LARGE_PAGE_SIZE_8M - 1);
-		if (!IS_ENABLED(CONFIG_PIN_TLB_TEXT))
-			mmu_patch_cmp_limit(&patch__itlbmiss_linmem_top, einittext8);
-
-		/*
-		 * Populate page tables to:
-		 * - have them appear in /sys/kernel/debug/kernel_page_tables
-		 * - allow the BDI to find the pages when they are not PINNED
-		 */
-		mmu_mapin_ram_chunk(0, einittext8, PAGE_KERNEL_X);
-		mmu_mapin_ram_chunk(einittext8, mapped, PAGE_KERNEL);
-		mmu_mapin_immr();
+		mmu_mapin_ram_chunk(boundary, einittext8, PAGE_KERNEL_TEXT, true);
+		mmu_mapin_ram_chunk(einittext8, top, PAGE_KERNEL, true);
 	}
 
-	mmu_patch_cmp_limit(&patch__dtlbmiss_linmem_top, mapped);
-	mmu_patch_cmp_limit(&patch__fixupdar_linmem_top, mapped);
-
-	/* If the size of RAM is not an exact power of two, we may not
-	 * have covered RAM in its entirety with 8 MiB
-	 * pages. Consequently, restrict the top end of RAM currently
-	 * allocable so that calls to the MEMBLOCK to allocate PTEs for "tail"
-	 * coverage with normal-sized pages (or other reasons) do not
-	 * attempt to allocate outside the allowed range.
-	 */
-	if (mapped)
-		memblock_set_current_limit(mapped);
+	if (top > SZ_32M)
+		memblock_set_current_limit(top);
 
-	block_mapped_ram = mapped;
+	block_mapped_ram = top;
 
-	return mapped;
+	return top;
 }
 
 void mmu_mark_initmem_nx(void)
 {
-	if (IS_ENABLED(CONFIG_STRICT_KERNEL_RWX) && CONFIG_ETEXT_SHIFT < 23)
-		mmu_patch_addis(&patch__itlbmiss_linmem_top8,
-				-((long)_etext & ~(LARGE_PAGE_SIZE_8M - 1)));
-	if (!IS_ENABLED(CONFIG_PIN_TLB_TEXT)) {
-		unsigned long einittext8 = ALIGN(__pa(_einittext), SZ_8M);
-		unsigned long etext8 = ALIGN(__pa(_etext), SZ_8M);
-		unsigned long etext = __pa(_etext);
-
-		mmu_patch_cmp_limit(&patch__itlbmiss_linmem_top, __pa(_etext));
-
-		/* Update page tables for PTDUMP and BDI */
-		mmu_mapin_ram_chunk(0, einittext8, __pgprot(0));
-		if (IS_ENABLED(CONFIG_STRICT_KERNEL_RWX)) {
-			mmu_mapin_ram_chunk(0, etext, PAGE_KERNEL_TEXT);
-			mmu_mapin_ram_chunk(etext, einittext8, PAGE_KERNEL);
-		} else {
-			mmu_mapin_ram_chunk(0, etext8, PAGE_KERNEL_TEXT);
-			mmu_mapin_ram_chunk(etext8, einittext8, PAGE_KERNEL);
-		}
-	}
+	unsigned long etext8 = ALIGN(__pa(_etext), SZ_8M);
+	unsigned long sinittext = __pa(_sinittext);
+	unsigned long boundary = strict_kernel_rwx_enabled() ? sinittext : etext8;
+	unsigned long einittext8 = ALIGN(__pa(_einittext), SZ_8M);
+
+	if (!debug_pagealloc_enabled_or_kfence())
+		mmu_mapin_ram_chunk(boundary, einittext8, PAGE_KERNEL, false);
+
+	mmu_pin_tlb(block_mapped_ram, false);
 }
 
 #ifdef CONFIG_STRICT_KERNEL_RWX
 void mmu_mark_rodata_ro(void)
 {
 	unsigned long sinittext = __pa(_sinittext);
-	unsigned long etext = __pa(_etext);
-
-	if (CONFIG_DATA_SHIFT < 23)
-		mmu_patch_addis(&patch__dtlbmiss_romem_top8,
-				-__pa(((unsigned long)_sinittext) &
-				      ~(LARGE_PAGE_SIZE_8M - 1)));
-	mmu_patch_addis(&patch__dtlbmiss_romem_top, -__pa(_sinittext));
-
-	/* Update page tables for PTDUMP and BDI */
-	mmu_mapin_ram_chunk(0, sinittext, __pgprot(0));
-	mmu_mapin_ram_chunk(0, etext, PAGE_KERNEL_ROX);
-	mmu_mapin_ram_chunk(etext, sinittext, PAGE_KERNEL_RO);
+
+	mmu_mapin_ram_chunk(0, sinittext, PAGE_KERNEL_ROX, false);
+	if (IS_ENABLED(CONFIG_PIN_TLB_DATA))
+		mmu_pin_tlb(block_mapped_ram, true);
 }
 #endif
 
@@ -214,67 +199,15 @@ void __init setup_initial_memory_limit(phys_addr_t first_memblock_base,
 	BUG_ON(first_memblock_base != 0);
 
 	/* 8xx can only access 32MB at the moment */
-	memblock_set_current_limit(min_t(u64, first_memblock_size, 0x02000000));
+	memblock_set_current_limit(min_t(u64, first_memblock_size, SZ_32M));
 }
 
-/*
- * Set up to use a given MMU context.
- * id is context number, pgd is PGD pointer.
- *
- * We place the physical address of the new task page directory loaded
- * into the MMU base register, and set the ASID compare register with
- * the new "context."
- */
-void set_context(unsigned long id, pgd_t *pgd)
+int pud_clear_huge(pud_t *pud)
 {
-	s16 offset = (s16)(__pa(swapper_pg_dir));
-
-	/* Context switch the PTE pointer for the Abatron BDI2000.
-	 * The PGDIR is passed as second argument.
-	 */
-	if (IS_ENABLED(CONFIG_BDI_SWITCH))
-		abatron_pteptrs[1] = pgd;
-
-	/* Register M_TWB will contain base address of level 1 table minus the
-	 * lower part of the kernel PGDIR base address, so that all accesses to
-	 * level 1 table are done relative to lower part of kernel PGDIR base
-	 * address.
-	 */
-	mtspr(SPRN_M_TWB, __pa(pgd) - offset);
-
-	/* Update context */
-	mtspr(SPRN_M_CASID, id - 1);
-	/* sync */
-	mb();
-}
-
-void flush_instruction_cache(void)
-{
-	isync();
-	mtspr(SPRN_IC_CST, IDC_INVALL);
-	isync();
+	 return 0;
 }
 
-#ifdef CONFIG_PPC_KUEP
-void __init setup_kuep(bool disabled)
+int pmd_clear_huge(pmd_t *pmd)
 {
-	if (disabled)
-		return;
-
-	pr_info("Activating Kernel Userspace Execution Prevention\n");
-
-	mtspr(SPRN_MI_AP, MI_APG_KUEP);
+	 return 0;
 }
-#endif
-
-#ifdef CONFIG_PPC_KUAP
-void __init setup_kuap(bool disabled)
-{
-	pr_info("Activating Kernel Userspace Access Protection\n");
-
-	if (disabled)
-		pr_warn("KUAP cannot be disabled yet on 8xx when compiled in\n");
-
-	mtspr(SPRN_MD_AP, MD_APG_KUAP);
-}
-#endif