1 files changed, 89 insertions, 906 deletions

diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c
index e1bf5ca397fe..d3c1b749dcfc 100644
--- a/arch/powerpc/mm/hugetlbpage.c
+++ b/arch/powerpc/mm/hugetlbpage.c
@@ -15,340 +15,84 @@
 #include <linux/export.h>
 #include <linux/of_fdt.h>
 #include <linux/memblock.h>
-#include <linux/bootmem.h>
 #include <linux/moduleparam.h>
 #include <linux/swap.h>
 #include <linux/swapops.h>
-#include <asm/pgtable.h>
+#include <linux/kmemleak.h>
 #include <asm/pgalloc.h>
 #include <asm/tlb.h>
 #include <asm/setup.h>
 #include <asm/hugetlb.h>
+#include <asm/pte-walk.h>
+#include <asm/firmware.h>
 
-#ifdef CONFIG_HUGETLB_PAGE
+bool hugetlb_disabled = false;
 
-#define PAGE_SHIFT_64K	16
-#define PAGE_SHIFT_512K	19
-#define PAGE_SHIFT_8M	23
-#define PAGE_SHIFT_16M	24
-#define PAGE_SHIFT_16G	34
-
-unsigned int HPAGE_SHIFT;
-EXPORT_SYMBOL(HPAGE_SHIFT);
-
-/*
- * Tracks gpages after the device tree is scanned and before the
- * huge_boot_pages list is ready.  On non-Freescale implementations, this is
- * just used to track 16G pages and so is a single array.  FSL-based
- * implementations may have more than one gpage size, so we need multiple
- * arrays
- */
-#if defined(CONFIG_PPC_FSL_BOOK3E) || defined(CONFIG_PPC_8xx)
-#define MAX_NUMBER_GPAGES	128
-struct psize_gpages {
-	u64 gpage_list[MAX_NUMBER_GPAGES];
-	unsigned int nr_gpages;
-};
-static struct psize_gpages gpage_freearray[MMU_PAGE_COUNT];
-#else
-#define MAX_NUMBER_GPAGES	1024
-static u64 gpage_freearray[MAX_NUMBER_GPAGES];
-static unsigned nr_gpages;
-#endif
-
-#define hugepd_none(hpd)	(hpd_val(hpd) == 0)
+#define PTE_T_ORDER	(__builtin_ffs(sizeof(pte_basic_t)) - \
+			 __builtin_ffs(sizeof(void *)))
 
 pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr, unsigned long sz)
 {
-	/* Only called for hugetlbfs pages, hence can ignore THP */
-	return __find_linux_pte_or_hugepte(mm->pgd, addr, NULL, NULL);
-}
-
-static int __hugepte_alloc(struct mm_struct *mm, hugepd_t *hpdp,
-			   unsigned long address, unsigned pdshift, unsigned pshift)
-{
-	struct kmem_cache *cachep;
-	pte_t *new;
-	int i;
-	int num_hugepd;
-
-	if (pshift >= pdshift) {
-		cachep = hugepte_cache;
-		num_hugepd = 1 << (pshift - pdshift);
-	} else {
-		cachep = PGT_CACHE(pdshift - pshift);
-		num_hugepd = 1;
-	}
-
-	new = kmem_cache_zalloc(cachep, pgtable_gfp_flags(mm, GFP_KERNEL));
-
-	BUG_ON(pshift > HUGEPD_SHIFT_MASK);
-	BUG_ON((unsigned long)new & HUGEPD_SHIFT_MASK);
-
-	if (! new)
-		return -ENOMEM;
-
 	/*
-	 * Make sure other cpus find the hugepd set only after a
-	 * properly initialized page table is visible to them.
-	 * For more details look for comment in __pte_alloc().
+	 * Only called for hugetlbfs pages, hence can ignore THP and the
+	 * irq disabled walk.
 	 */
-	smp_wmb();
-
-	spin_lock(&mm->page_table_lock);
-
-	/*
-	 * We have multiple higher-level entries that point to the same
-	 * actual pte location.  Fill in each as we go and backtrack on error.
-	 * We need all of these so the DTLB pgtable walk code can find the
-	 * right higher-level entry without knowing if it's a hugepage or not.
-	 */
-	for (i = 0; i < num_hugepd; i++, hpdp++) {
-		if (unlikely(!hugepd_none(*hpdp)))
-			break;
-		else {
-#ifdef CONFIG_PPC_BOOK3S_64
-			*hpdp = __hugepd(__pa(new) |
-					 (shift_to_mmu_psize(pshift) << 2));
-#elif defined(CONFIG_PPC_8xx)
-			*hpdp = __hugepd(__pa(new) |
-					 (pshift == PAGE_SHIFT_8M ? _PMD_PAGE_8M :
-					  _PMD_PAGE_512K) | _PMD_PRESENT);
-#else
-			/* We use the old format for PPC_FSL_BOOK3E */
-			*hpdp = __hugepd(((unsigned long)new & ~PD_HUGE) | pshift);
-#endif
-		}
-	}
-	/* If we bailed from the for loop early, an error occurred, clean up */
-	if (i < num_hugepd) {
-		for (i = i - 1 ; i >= 0; i--, hpdp--)
-			*hpdp = __hugepd(0);
-		kmem_cache_free(cachep, new);
-	}
-	spin_unlock(&mm->page_table_lock);
-	return 0;
+	return __find_linux_pte(mm->pgd, addr, NULL, NULL);
 }
 
-/*
- * These macros define how to determine which level of the page table holds
- * the hpdp.
- */
-#if defined(CONFIG_PPC_FSL_BOOK3E) || defined(CONFIG_PPC_8xx)
-#define HUGEPD_PGD_SHIFT PGDIR_SHIFT
-#define HUGEPD_PUD_SHIFT PUD_SHIFT
-#else
-#define HUGEPD_PGD_SHIFT PUD_SHIFT
-#define HUGEPD_PUD_SHIFT PMD_SHIFT
-#endif
-
-/*
- * At this point we do the placement change only for BOOK3S 64. This would
- * possibly work on other subarchs.
- */
-pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned long addr, unsigned long sz)
+pte_t *huge_pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma,
+		      unsigned long addr, unsigned long sz)
 {
-	pgd_t *pg;
-	pud_t *pu;
-	pmd_t *pm;
-	hugepd_t *hpdp = NULL;
-	unsigned pshift = __ffs(sz);
-	unsigned pdshift = PGDIR_SHIFT;
-
-	addr &= ~(sz-1);
-	pg = pgd_offset(mm, addr);
+	p4d_t *p4d;
+	pud_t *pud;
+	pmd_t *pmd;
 
-#ifdef CONFIG_PPC_BOOK3S_64
-	if (pshift == PGDIR_SHIFT)
-		/* 16GB huge page */
-		return (pte_t *) pg;
-	else if (pshift > PUD_SHIFT)
-		/*
-		 * We need to use hugepd table
-		 */
-		hpdp = (hugepd_t *)pg;
-	else {
-		pdshift = PUD_SHIFT;
-		pu = pud_alloc(mm, pg, addr);
-		if (pshift == PUD_SHIFT)
-			return (pte_t *)pu;
-		else if (pshift > PMD_SHIFT)
-			hpdp = (hugepd_t *)pu;
-		else {
-			pdshift = PMD_SHIFT;
-			pm = pmd_alloc(mm, pu, addr);
-			if (pshift == PMD_SHIFT)
-				/* 16MB hugepage */
-				return (pte_t *)pm;
-			else
-				hpdp = (hugepd_t *)pm;
-		}
-	}
-#else
-	if (pshift >= HUGEPD_PGD_SHIFT) {
-		hpdp = (hugepd_t *)pg;
-	} else {
-		pdshift = PUD_SHIFT;
-		pu = pud_alloc(mm, pg, addr);
-		if (pshift >= HUGEPD_PUD_SHIFT) {
-			hpdp = (hugepd_t *)pu;
-		} else {
-			pdshift = PMD_SHIFT;
-			pm = pmd_alloc(mm, pu, addr);
-			hpdp = (hugepd_t *)pm;
-		}
-	}
-#endif
-	if (!hpdp)
-		return NULL;
+	addr &= ~(sz - 1);
 
-	BUG_ON(!hugepd_none(*hpdp) && !hugepd_ok(*hpdp));
+	p4d = p4d_offset(pgd_offset(mm, addr), addr);
+	if (!mm_pud_folded(mm) && sz >= P4D_SIZE)
+		return (pte_t *)p4d;
 
-	if (hugepd_none(*hpdp) && __hugepte_alloc(mm, hpdp, addr, pdshift, pshift))
+	pud = pud_alloc(mm, p4d, addr);
+	if (!pud)
 		return NULL;
+	if (!mm_pmd_folded(mm) && sz >= PUD_SIZE)
+		return (pte_t *)pud;
 
-	return hugepte_offset(*hpdp, addr, pdshift);
-}
-
-#if defined(CONFIG_PPC_FSL_BOOK3E) || defined(CONFIG_PPC_8xx)
-/* Build list of addresses of gigantic pages.  This function is used in early
- * boot before the buddy allocator is setup.
- */
-void add_gpage(u64 addr, u64 page_size, unsigned long number_of_pages)
-{
-	unsigned int idx = shift_to_mmu_psize(__ffs(page_size));
-	int i;
-
-	if (addr == 0)
-		return;
-
-	gpage_freearray[idx].nr_gpages = number_of_pages;
-
-	for (i = 0; i < number_of_pages; i++) {
-		gpage_freearray[idx].gpage_list[i] = addr;
-		addr += page_size;
-	}
-}
-
-/*
- * Moves the gigantic page addresses from the temporary list to the
- * huge_boot_pages list.
- */
-int alloc_bootmem_huge_page(struct hstate *hstate)
-{
-	struct huge_bootmem_page *m;
-	int idx = shift_to_mmu_psize(huge_page_shift(hstate));
-	int nr_gpages = gpage_freearray[idx].nr_gpages;
-
-	if (nr_gpages == 0)
-		return 0;
-
-#ifdef CONFIG_HIGHMEM
-	/*
-	 * If gpages can be in highmem we can't use the trick of storing the
-	 * data structure in the page; allocate space for this
-	 */
-	m = memblock_virt_alloc(sizeof(struct huge_bootmem_page), 0);
-	m->phys = gpage_freearray[idx].gpage_list[--nr_gpages];
-#else
-	m = phys_to_virt(gpage_freearray[idx].gpage_list[--nr_gpages]);
-#endif
-
-	list_add(&m->list, &huge_boot_pages);
-	gpage_freearray[idx].nr_gpages = nr_gpages;
-	gpage_freearray[idx].gpage_list[nr_gpages] = 0;
-	m->hstate = hstate;
-
-	return 1;
-}
-/*
- * Scan the command line hugepagesz= options for gigantic pages; store those in
- * a list that we use to allocate the memory once all options are parsed.
- */
-
-unsigned long gpage_npages[MMU_PAGE_COUNT];
+	pmd = pmd_alloc(mm, pud, addr);
+	if (!pmd)
+		return NULL;
 
-static int __init do_gpage_early_setup(char *param, char *val,
-				       const char *unused, void *arg)
-{
-	static phys_addr_t size;
-	unsigned long npages;
+	if (sz >= PMD_SIZE) {
+		/* On 8xx, all hugepages are handled as contiguous PTEs */
+		if (IS_ENABLED(CONFIG_PPC_8xx)) {
+			int i;
 
-	/*
-	 * The hugepagesz and hugepages cmdline options are interleaved.  We
-	 * use the size variable to keep track of whether or not this was done
-	 * properly and skip over instances where it is incorrect.  Other
-	 * command-line parsing code will issue warnings, so we don't need to.
-	 *
-	 */
-	if ((strcmp(param, "default_hugepagesz") == 0) ||
-	    (strcmp(param, "hugepagesz") == 0)) {
-		size = memparse(val, NULL);
-	} else if (strcmp(param, "hugepages") == 0) {
-		if (size != 0) {
-			if (sscanf(val, "%lu", &npages) <= 0)
-				npages = 0;
-			if (npages > MAX_NUMBER_GPAGES) {
-				pr_warn("MMU: %lu pages requested for page "
-#ifdef CONFIG_PHYS_ADDR_T_64BIT
-					"size %llu KB, limiting to "
-#else
-					"size %u KB, limiting to "
-#endif
-					__stringify(MAX_NUMBER_GPAGES) "\n",
-					npages, size / 1024);
-				npages = MAX_NUMBER_GPAGES;
+			for (i = 0; i < sz / PMD_SIZE; i++) {
+				if (!pte_alloc_huge(mm, pmd + i, addr))
+					return NULL;
 			}
-			gpage_npages[shift_to_mmu_psize(__ffs(size))] = npages;
-			size = 0;
 		}
+		return (pte_t *)pmd;
 	}
-	return 0;
-}
 
+	return pte_alloc_huge(mm, pmd, addr);
+}
 
+#ifdef CONFIG_PPC_BOOK3S_64
 /*
- * This function allocates physical space for pages that are larger than the
- * buddy allocator can handle.  We want to allocate these in highmem because
- * the amount of lowmem is limited.  This means that this function MUST be
- * called before lowmem_end_addr is set up in MMU_init() in order for the lmb
- * allocate to grab highmem.
+ * Tracks gpages after the device tree is scanned and before the
+ * huge_boot_pages list is ready on pseries.
  */
-void __init reserve_hugetlb_gpages(void)
-{
-	static __initdata char cmdline[COMMAND_LINE_SIZE];
-	phys_addr_t size, base;
-	int i;
-
-	strlcpy(cmdline, boot_command_line, COMMAND_LINE_SIZE);
-	parse_args("hugetlb gpages", cmdline, NULL, 0, 0, 0,
-			NULL, &do_gpage_early_setup);
-
-	/*
-	 * Walk gpage list in reverse, allocating larger page sizes first.
-	 * Skip over unsupported sizes, or sizes that have 0 gpages allocated.
-	 * When we reach the point in the list where pages are no longer
-	 * considered gpages, we're done.
-	 */
-	for (i = MMU_PAGE_COUNT-1; i >= 0; i--) {
-		if (mmu_psize_defs[i].shift == 0 || gpage_npages[i] == 0)
-			continue;
-		else if (mmu_psize_to_shift(i) < (MAX_ORDER + PAGE_SHIFT))
-			break;
-
-		size = (phys_addr_t)(1ULL << mmu_psize_to_shift(i));
-		base = memblock_alloc_base(size * gpage_npages[i], size,
-					   MEMBLOCK_ALLOC_ANYWHERE);
-		add_gpage(base, size, gpage_npages[i]);
-	}
-}
-
-#else /* !PPC_FSL_BOOK3E */
+#define MAX_NUMBER_GPAGES	1024
+__initdata static u64 gpage_freearray[MAX_NUMBER_GPAGES];
+__initdata static unsigned nr_gpages;
 
-/* Build list of addresses of gigantic pages.  This function is used in early
+/*
+ * Build list of addresses of gigantic pages.  This function is used in early
  * boot before the buddy allocator is setup.
  */
-void add_gpage(u64 addr, u64 page_size, unsigned long number_of_pages)
+void __init pseries_add_gpage(u64 addr, u64 page_size, unsigned long number_of_pages)
 {
 	if (!addr)
 		return;
@@ -360,438 +104,82 @@ void add_gpage(u64 addr, u64 page_size, unsigned long number_of_pages)
 	}
 }
 
-/* Moves the gigantic page addresses from the temporary list to the
- * huge_boot_pages list.
- */
-int alloc_bootmem_huge_page(struct hstate *hstate)
+static int __init pseries_alloc_bootmem_huge_page(struct hstate *hstate)
 {
 	struct huge_bootmem_page *m;
 	if (nr_gpages == 0)
 		return 0;
 	m = phys_to_virt(gpage_freearray[--nr_gpages]);
 	gpage_freearray[nr_gpages] = 0;
-	list_add(&m->list, &huge_boot_pages);
+	list_add(&m->list, &huge_boot_pages[0]);
 	m->hstate = hstate;
+	m->flags = 0;
 	return 1;
 }
-#endif
-
-#if defined(CONFIG_PPC_FSL_BOOK3E) || defined(CONFIG_PPC_8xx)
-#define HUGEPD_FREELIST_SIZE \
-	((PAGE_SIZE - sizeof(struct hugepd_freelist)) / sizeof(pte_t))
-
-struct hugepd_freelist {
-	struct rcu_head	rcu;
-	unsigned int index;
-	void *ptes[0];
-};
-
-static DEFINE_PER_CPU(struct hugepd_freelist *, hugepd_freelist_cur);
-
-static void hugepd_free_rcu_callback(struct rcu_head *head)
-{
-	struct hugepd_freelist *batch =
-		container_of(head, struct hugepd_freelist, rcu);
-	unsigned int i;
-
-	for (i = 0; i < batch->index; i++)
-		kmem_cache_free(hugepte_cache, batch->ptes[i]);
-
-	free_page((unsigned long)batch);
-}
 
-static void hugepd_free(struct mmu_gather *tlb, void *hugepte)
+bool __init hugetlb_node_alloc_supported(void)
 {
-	struct hugepd_freelist **batchp;
-
-	batchp = &get_cpu_var(hugepd_freelist_cur);
-
-	if (atomic_read(&tlb->mm->mm_users) < 2 ||
-	    cpumask_equal(mm_cpumask(tlb->mm),
-			  cpumask_of(smp_processor_id()))) {
-		kmem_cache_free(hugepte_cache, hugepte);
-		put_cpu_var(hugepd_freelist_cur);
-		return;
-	}
-
-	if (*batchp == NULL) {
-		*batchp = (struct hugepd_freelist *)__get_free_page(GFP_ATOMIC);
-		(*batchp)->index = 0;
-	}
-
-	(*batchp)->ptes[(*batchp)->index++] = hugepte;
-	if ((*batchp)->index == HUGEPD_FREELIST_SIZE) {
-		call_rcu_sched(&(*batchp)->rcu, hugepd_free_rcu_callback);
-		*batchp = NULL;
-	}
-	put_cpu_var(hugepd_freelist_cur);
+	return false;
 }
-#else
-static inline void hugepd_free(struct mmu_gather *tlb, void *hugepte) {}
 #endif
 
-static void free_hugepd_range(struct mmu_gather *tlb, hugepd_t *hpdp, int pdshift,
-			      unsigned long start, unsigned long end,
-			      unsigned long floor, unsigned long ceiling)
-{
-	pte_t *hugepte = hugepd_page(*hpdp);
-	int i;
 
-	unsigned long pdmask = ~((1UL << pdshift) - 1);
-	unsigned int num_hugepd = 1;
-	unsigned int shift = hugepd_shift(*hpdp);
-
-	/* Note: On fsl the hpdp may be the first of several */
-	if (shift > pdshift)
-		num_hugepd = 1 << (shift - pdshift);
-
-	start &= pdmask;
-	if (start < floor)
-		return;
-	if (ceiling) {
-		ceiling &= pdmask;
-		if (! ceiling)
-			return;
-	}
-	if (end - 1 > ceiling - 1)
-		return;
-
-	for (i = 0; i < num_hugepd; i++, hpdp++)
-		*hpdp = __hugepd(0);
-
-	if (shift >= pdshift)
-		hugepd_free(tlb, hugepte);
-	else
-		pgtable_free_tlb(tlb, hugepte, pdshift - shift);
-}
-
-static void hugetlb_free_pmd_range(struct mmu_gather *tlb, pud_t *pud,
-				   unsigned long addr, unsigned long end,
-				   unsigned long floor, unsigned long ceiling)
+int __init alloc_bootmem_huge_page(struct hstate *h, int nid)
 {
-	pmd_t *pmd;
-	unsigned long next;
-	unsigned long start;
-
-	start = addr;
-	do {
-		unsigned long more;
-
-		pmd = pmd_offset(pud, addr);
-		next = pmd_addr_end(addr, end);
-		if (!is_hugepd(__hugepd(pmd_val(*pmd)))) {
-			/*
-			 * if it is not hugepd pointer, we should already find
-			 * it cleared.
-			 */
-			WARN_ON(!pmd_none_or_clear_bad(pmd));
-			continue;
-		}
-		/*
-		 * Increment next by the size of the huge mapping since
-		 * there may be more than one entry at this level for a
-		 * single hugepage, but all of them point to
-		 * the same kmem cache that holds the hugepte.
-		 */
-		more = addr + (1 << hugepd_shift(*(hugepd_t *)pmd));
-		if (more > next)
-			next = more;
-
-		free_hugepd_range(tlb, (hugepd_t *)pmd, PMD_SHIFT,
-				  addr, next, floor, ceiling);
-	} while (addr = next, addr != end);
-
-	start &= PUD_MASK;
-	if (start < floor)
-		return;
-	if (ceiling) {
-		ceiling &= PUD_MASK;
-		if (!ceiling)
-			return;
-	}
-	if (end - 1 > ceiling - 1)
-		return;
 
-	pmd = pmd_offset(pud, start);
-	pud_clear(pud);
-	pmd_free_tlb(tlb, pmd, start);
-	mm_dec_nr_pmds(tlb->mm);
-}
-
-static void hugetlb_free_pud_range(struct mmu_gather *tlb, pgd_t *pgd,
-				   unsigned long addr, unsigned long end,
-				   unsigned long floor, unsigned long ceiling)
-{
-	pud_t *pud;
-	unsigned long next;
-	unsigned long start;
-
-	start = addr;
-	do {
-		pud = pud_offset(pgd, addr);
-		next = pud_addr_end(addr, end);
-		if (!is_hugepd(__hugepd(pud_val(*pud)))) {
-			if (pud_none_or_clear_bad(pud))
-				continue;
-			hugetlb_free_pmd_range(tlb, pud, addr, next, floor,
-					       ceiling);
-		} else {
-			unsigned long more;
-			/*
-			 * Increment next by the size of the huge mapping since
-			 * there may be more than one entry at this level for a
-			 * single hugepage, but all of them point to
-			 * the same kmem cache that holds the hugepte.
-			 */
-			more = addr + (1 << hugepd_shift(*(hugepd_t *)pud));
-			if (more > next)
-				next = more;
-
-			free_hugepd_range(tlb, (hugepd_t *)pud, PUD_SHIFT,
-					  addr, next, floor, ceiling);
-		}
-	} while (addr = next, addr != end);
-
-	start &= PGDIR_MASK;
-	if (start < floor)
-		return;
-	if (ceiling) {
-		ceiling &= PGDIR_MASK;
-		if (!ceiling)
-			return;
-	}
-	if (end - 1 > ceiling - 1)
-		return;
-
-	pud = pud_offset(pgd, start);
-	pgd_clear(pgd);
-	pud_free_tlb(tlb, pud, start);
-}
-
-/*
- * This function frees user-level page tables of a process.
- */
-void hugetlb_free_pgd_range(struct mmu_gather *tlb,
-			    unsigned long addr, unsigned long end,
-			    unsigned long floor, unsigned long ceiling)
-{
-	pgd_t *pgd;
-	unsigned long next;
-
-	/*
-	 * Because there are a number of different possible pagetable
-	 * layouts for hugepage ranges, we limit knowledge of how
-	 * things should be laid out to the allocation path
-	 * (huge_pte_alloc(), above).  Everything else works out the
-	 * structure as it goes from information in the hugepd
-	 * pointers.  That means that we can't here use the
-	 * optimization used in the normal page free_pgd_range(), of
-	 * checking whether we're actually covering a large enough
-	 * range to have to do anything at the top level of the walk
-	 * instead of at the bottom.
-	 *
-	 * To make sense of this, you should probably go read the big
-	 * block comment at the top of the normal free_pgd_range(),
-	 * too.
-	 */
-
-	do {
-		next = pgd_addr_end(addr, end);
-		pgd = pgd_offset(tlb->mm, addr);
-		if (!is_hugepd(__hugepd(pgd_val(*pgd)))) {
-			if (pgd_none_or_clear_bad(pgd))
-				continue;
-			hugetlb_free_pud_range(tlb, pgd, addr, next, floor, ceiling);
-		} else {
-			unsigned long more;
-			/*
-			 * Increment next by the size of the huge mapping since
-			 * there may be more than one entry at the pgd level
-			 * for a single hugepage, but all of them point to the
-			 * same kmem cache that holds the hugepte.
-			 */
-			more = addr + (1 << hugepd_shift(*(hugepd_t *)pgd));
-			if (more > next)
-				next = more;
-
-			free_hugepd_range(tlb, (hugepd_t *)pgd, PGDIR_SHIFT,
-					  addr, next, floor, ceiling);
-		}
-	} while (addr = next, addr != end);
-}
-
-struct page *follow_huge_pd(struct vm_area_struct *vma,
-			    unsigned long address, hugepd_t hpd,
-			    int flags, int pdshift)
-{
-	pte_t *ptep;
-	spinlock_t *ptl;
-	struct page *page = NULL;
-	unsigned long mask;
-	int shift = hugepd_shift(hpd);
-	struct mm_struct *mm = vma->vm_mm;
-
-retry:
-	ptl = &mm->page_table_lock;
-	spin_lock(ptl);
-
-	ptep = hugepte_offset(hpd, address, pdshift);
-	if (pte_present(*ptep)) {
-		mask = (1UL << shift) - 1;
-		page = pte_page(*ptep);
-		page += ((address & mask) >> PAGE_SHIFT);
-		if (flags & FOLL_GET)
-			get_page(page);
-	} else {
-		if (is_hugetlb_entry_migration(*ptep)) {
-			spin_unlock(ptl);
-			__migration_entry_wait(mm, ptep, ptl);
-			goto retry;
-		}
-	}
-	spin_unlock(ptl);
-	return page;
-}
-
-static unsigned long hugepte_addr_end(unsigned long addr, unsigned long end,
-				      unsigned long sz)
-{
-	unsigned long __boundary = (addr + sz) & ~(sz-1);
-	return (__boundary - 1 < end - 1) ? __boundary : end;
-}
-
-int gup_huge_pd(hugepd_t hugepd, unsigned long addr, unsigned pdshift,
-		unsigned long end, int write, struct page **pages, int *nr)
-{
-	pte_t *ptep;
-	unsigned long sz = 1UL << hugepd_shift(hugepd);
-	unsigned long next;
-
-	ptep = hugepte_offset(hugepd, addr, pdshift);
-	do {
-		next = hugepte_addr_end(addr, end, sz);
-		if (!gup_hugepte(ptep, sz, addr, end, write, pages, nr))
-			return 0;
-	} while (ptep++, addr = next, addr != end);
-
-	return 1;
-}
-
-#ifdef CONFIG_PPC_MM_SLICES
-unsigned long hugetlb_get_unmapped_area(struct file *file, unsigned long addr,
-					unsigned long len, unsigned long pgoff,
-					unsigned long flags)
-{
-	struct hstate *hstate = hstate_file(file);
-	int mmu_psize = shift_to_mmu_psize(huge_page_shift(hstate));
-
-	if (radix_enabled())
-		return radix__hugetlb_get_unmapped_area(file, addr, len,
-						       pgoff, flags);
-	return slice_get_unmapped_area(addr, len, flags, mmu_psize, 1);
-}
-#endif
-
-unsigned long vma_mmu_pagesize(struct vm_area_struct *vma)
-{
-#ifdef CONFIG_PPC_MM_SLICES
-	unsigned int psize = get_slice_psize(vma->vm_mm, vma->vm_start);
-	/* With radix we don't use slice, so derive it from vma*/
-	if (!radix_enabled())
-		return 1UL << mmu_psize_to_shift(psize);
+#ifdef CONFIG_PPC_BOOK3S_64
+	if (firmware_has_feature(FW_FEATURE_LPAR) && !radix_enabled())
+		return pseries_alloc_bootmem_huge_page(h);
 #endif
-	if (!is_vm_hugetlb_page(vma))
-		return PAGE_SIZE;
-
-	return huge_page_size(hstate_vma(vma));
+	return __alloc_bootmem_huge_page(h, nid);
 }
 
-static inline bool is_power_of_4(unsigned long x)
-{
-	if (is_power_of_2(x))
-		return (__ilog2(x) % 2) ? false : true;
-	return false;
-}
-
-static int __init add_huge_page_size(unsigned long long size)
+bool __init arch_hugetlb_valid_size(unsigned long size)
 {
 	int shift = __ffs(size);
 	int mmu_psize;
 
 	/* Check that it is a page size supported by the hardware and
 	 * that it fits within pagetable and slice limits. */
-	if (size <= PAGE_SIZE)
-		return -EINVAL;
-#if defined(CONFIG_PPC_FSL_BOOK3E)
-	if (!is_power_of_4(size))
-		return -EINVAL;
-#elif !defined(CONFIG_PPC_8xx)
-	if (!is_power_of_2(size) || (shift > SLICE_HIGH_SHIFT))
-		return -EINVAL;
-#endif
+	if (size <= PAGE_SIZE || !is_power_of_2(size))
+		return false;
 
-	if ((mmu_psize = shift_to_mmu_psize(shift)) < 0)
-		return -EINVAL;
-
-#ifdef CONFIG_PPC_BOOK3S_64
-	/*
-	 * We need to make sure that for different page sizes reported by
-	 * firmware we only add hugetlb support for page sizes that can be
-	 * supported by linux page table layout.
-	 * For now we have
-	 * Radix: 2M
-	 * Hash: 16M and 16G
-	 */
-	if (radix_enabled()) {
-		if (mmu_psize != MMU_PAGE_2M) {
-			if (cpu_has_feature(CPU_FTR_POWER9_DD1) ||
-			    (mmu_psize != MMU_PAGE_1G))
-				return -EINVAL;
-		}
-	} else {
-		if (mmu_psize != MMU_PAGE_16M && mmu_psize != MMU_PAGE_16G)
-			return -EINVAL;
-	}
-#endif
+	mmu_psize = check_and_get_huge_psize(shift);
+	if (mmu_psize < 0)
+		return false;
 
 	BUG_ON(mmu_psize_defs[mmu_psize].shift != shift);
 
-	/* Return if huge page size has already been setup */
-	if (size_to_hstate(size))
-		return 0;
-
-	hugetlb_add_hstate(shift - PAGE_SHIFT);
-
-	return 0;
+	return true;
 }
 
-static int __init hugepage_setup_sz(char *str)
+static int __init add_huge_page_size(unsigned long long size)
 {
-	unsigned long long size;
-
-	size = memparse(str, &str);
+	int shift = __ffs(size);
 
-	if (add_huge_page_size(size) != 0) {
-		hugetlb_bad_size();
-		pr_err("Invalid huge page size specified(%llu)\n", size);
-	}
+	if (!arch_hugetlb_valid_size((unsigned long)size))
+		return -EINVAL;
 
-	return 1;
+	hugetlb_add_hstate(shift - PAGE_SHIFT);
+	return 0;
 }
-__setup("hugepagesz=", hugepage_setup_sz);
 
-struct kmem_cache *hugepte_cache;
 static int __init hugetlbpage_init(void)
 {
+	bool configured = false;
 	int psize;
 
-#if !defined(CONFIG_PPC_FSL_BOOK3E) && !defined(CONFIG_PPC_8xx)
-	if (!radix_enabled() && !mmu_has_feature(MMU_FTR_16M_PAGE))
+	if (hugetlb_disabled) {
+		pr_info("HugeTLB support is disabled!\n");
+		return 0;
+	}
+
+	if (IS_ENABLED(CONFIG_PPC_BOOK3S_64) && !radix_enabled() &&
+	    !mmu_has_feature(MMU_FTR_16M_PAGE))
 		return -ENODEV;
-#endif
+
 	for (psize = 0; psize < MMU_PAGE_COUNT; ++psize) {
 		unsigned shift;
-		unsigned pdshift;
 
 		if (!mmu_psize_defs[psize].shift)
 			continue;
@@ -801,234 +189,29 @@ static int __init hugetlbpage_init(void)
 		if (add_huge_page_size(1ULL << shift) < 0)
 			continue;
 
-		if (shift < HUGEPD_PUD_SHIFT)
-			pdshift = PMD_SHIFT;
-		else if (shift < HUGEPD_PGD_SHIFT)
-			pdshift = PUD_SHIFT;
-		else
-			pdshift = PGDIR_SHIFT;
-		/*
-		 * if we have pdshift and shift value same, we don't
-		 * use pgt cache for hugepd.
-		 */
-		if (pdshift > shift)
-			pgtable_cache_add(pdshift - shift, NULL);
-#if defined(CONFIG_PPC_FSL_BOOK3E) || defined(CONFIG_PPC_8xx)
-		else if (!hugepte_cache) {
-			/*
-			 * Create a kmem cache for hugeptes.  The bottom bits in
-			 * the pte have size information encoded in them, so
-			 * align them to allow this
-			 */
-			hugepte_cache = kmem_cache_create("hugepte-cache",
-							  sizeof(pte_t),
-							  HUGEPD_SHIFT_MASK + 1,
-							  0, NULL);
-			if (hugepte_cache == NULL)
-				panic("%s: Unable to create kmem cache "
-				      "for hugeptes\n", __func__);
-
-		}
-#endif
+		configured = true;
 	}
 
-#if defined(CONFIG_PPC_FSL_BOOK3E) || defined(CONFIG_PPC_8xx)
-	/* Default hpage size = 4M on FSL_BOOK3E and 512k on 8xx */
-	if (mmu_psize_defs[MMU_PAGE_4M].shift)
-		HPAGE_SHIFT = mmu_psize_defs[MMU_PAGE_4M].shift;
-	else if (mmu_psize_defs[MMU_PAGE_512K].shift)
-		HPAGE_SHIFT = mmu_psize_defs[MMU_PAGE_512K].shift;
-#else
-	/* Set default large page size. Currently, we pick 16M or 1M
-	 * depending on what is available
-	 */
-	if (mmu_psize_defs[MMU_PAGE_16M].shift)
-		HPAGE_SHIFT = mmu_psize_defs[MMU_PAGE_16M].shift;
-	else if (mmu_psize_defs[MMU_PAGE_1M].shift)
-		HPAGE_SHIFT = mmu_psize_defs[MMU_PAGE_1M].shift;
-	else if (mmu_psize_defs[MMU_PAGE_2M].shift)
-		HPAGE_SHIFT = mmu_psize_defs[MMU_PAGE_2M].shift;
-#endif
+	if (!configured)
+		pr_info("Failed to initialize. Disabling HugeTLB");
+
 	return 0;
 }
 
 arch_initcall(hugetlbpage_init);
 
-void flush_dcache_icache_hugepage(struct page *page)
-{
-	int i;
-	void *start;
-
-	BUG_ON(!PageCompound(page));
-
-	for (i = 0; i < (1UL << compound_order(page)); i++) {
-		if (!PageHighMem(page)) {
-			__flush_dcache_icache(page_address(page+i));
-		} else {
-			start = kmap_atomic(page+i);
-			__flush_dcache_icache(start);
-			kunmap_atomic(start);
-		}
-	}
-}
-
-#endif /* CONFIG_HUGETLB_PAGE */
-
-/*
- * We have 4 cases for pgds and pmds:
- * (1) invalid (all zeroes)
- * (2) pointer to next table, as normal; bottom 6 bits == 0
- * (3) leaf pte for huge page _PAGE_PTE set
- * (4) hugepd pointer, _PAGE_PTE = 0 and bits [2..6] indicate size of table
- *
- * So long as we atomically load page table pointers we are safe against teardown,
- * we can follow the address down to the the page and take a ref on it.
- * This function need to be called with interrupts disabled. We use this variant
- * when we have MSR[EE] = 0 but the paca->soft_enabled = 1
- */
-
-pte_t *__find_linux_pte_or_hugepte(pgd_t *pgdir, unsigned long ea,
-				   bool *is_thp, unsigned *shift)
+void __init gigantic_hugetlb_cma_reserve(void)
 {
-	pgd_t pgd, *pgdp;
-	pud_t pud, *pudp;
-	pmd_t pmd, *pmdp;
-	pte_t *ret_pte;
-	hugepd_t *hpdp = NULL;
-	unsigned pdshift = PGDIR_SHIFT;
+	unsigned long order = 0;
 
-	if (shift)
-		*shift = 0;
-
-	if (is_thp)
-		*is_thp = false;
-
-	pgdp = pgdir + pgd_index(ea);
-	pgd  = READ_ONCE(*pgdp);
-	/*
-	 * Always operate on the local stack value. This make sure the
-	 * value don't get updated by a parallel THP split/collapse,
-	 * page fault or a page unmap. The return pte_t * is still not
-	 * stable. So should be checked there for above conditions.
-	 */
-	if (pgd_none(pgd))
-		return NULL;
-	else if (pgd_huge(pgd)) {
-		ret_pte = (pte_t *) pgdp;
-		goto out;
-	} else if (is_hugepd(__hugepd(pgd_val(pgd))))
-		hpdp = (hugepd_t *)&pgd;
-	else {
+	if (radix_enabled())
+		order = PUD_SHIFT - PAGE_SHIFT;
+	else if (!firmware_has_feature(FW_FEATURE_LPAR) && mmu_psize_defs[MMU_PAGE_16G].shift)
 		/*
-		 * Even if we end up with an unmap, the pgtable will not
-		 * be freed, because we do an rcu free and here we are
-		 * irq disabled
+		 * For pseries we do use ibm,expected#pages for reserving 16G pages.
 		 */
-		pdshift = PUD_SHIFT;
-		pudp = pud_offset(&pgd, ea);
-		pud  = READ_ONCE(*pudp);
-
-		if (pud_none(pud))
-			return NULL;
-		else if (pud_huge(pud)) {
-			ret_pte = (pte_t *) pudp;
-			goto out;
-		} else if (is_hugepd(__hugepd(pud_val(pud))))
-			hpdp = (hugepd_t *)&pud;
-		else {
-			pdshift = PMD_SHIFT;
-			pmdp = pmd_offset(&pud, ea);
-			pmd  = READ_ONCE(*pmdp);
-			/*
-			 * A hugepage collapse is captured by pmd_none, because
-			 * it mark the pmd none and do a hpte invalidate.
-			 */
-			if (pmd_none(pmd))
-				return NULL;
-
-			if (pmd_trans_huge(pmd) || pmd_devmap(pmd)) {
-				if (is_thp)
-					*is_thp = true;
-				ret_pte = (pte_t *) pmdp;
-				goto out;
-			}
-
-			if (pmd_huge(pmd)) {
-				ret_pte = (pte_t *) pmdp;
-				goto out;
-			} else if (is_hugepd(__hugepd(pmd_val(pmd))))
-				hpdp = (hugepd_t *)&pmd;
-			else
-				return pte_offset_kernel(&pmd, ea);
-		}
-	}
-	if (!hpdp)
-		return NULL;
-
-	ret_pte = hugepte_offset(*hpdp, ea, pdshift);
-	pdshift = hugepd_shift(*hpdp);
-out:
-	if (shift)
-		*shift = pdshift;
-	return ret_pte;
-}
-EXPORT_SYMBOL_GPL(__find_linux_pte_or_hugepte);
-
-int gup_hugepte(pte_t *ptep, unsigned long sz, unsigned long addr,
-		unsigned long end, int write, struct page **pages, int *nr)
-{
-	unsigned long mask;
-	unsigned long pte_end;
-	struct page *head, *page;
-	pte_t pte;
-	int refs;
+		order = mmu_psize_to_shift(MMU_PAGE_16G) - PAGE_SHIFT;
 
-	pte_end = (addr + sz) & ~(sz-1);
-	if (pte_end < end)
-		end = pte_end;
-
-	pte = READ_ONCE(*ptep);
-	mask = _PAGE_PRESENT | _PAGE_READ;
-
-	/*
-	 * On some CPUs like the 8xx, _PAGE_RW hence _PAGE_WRITE is defined
-	 * as 0 and _PAGE_RO has to be set when a page is not writable
-	 */
-	if (write)
-		mask |= _PAGE_WRITE;
-	else
-		mask |= _PAGE_RO;
-
-	if ((pte_val(pte) & mask) != mask)
-		return 0;
-
-	/* hugepages are never "special" */
-	VM_BUG_ON(!pfn_valid(pte_pfn(pte)));
-
-	refs = 0;
-	head = pte_page(pte);
-
-	page = head + ((addr & (sz-1)) >> PAGE_SHIFT);
-	do {
-		VM_BUG_ON(compound_head(page) != head);
-		pages[*nr] = page;
-		(*nr)++;
-		page++;
-		refs++;
-	} while (addr += PAGE_SIZE, addr != end);
-
-	if (!page_cache_add_speculative(head, refs)) {
-		*nr -= refs;
-		return 0;
-	}
-
-	if (unlikely(pte_val(pte) != pte_val(*ptep))) {
-		/* Could be optimized better */
-		*nr -= refs;
-		while (refs--)
-			put_page(head);
-		return 0;
-	}
-
-	return 1;
+	if (order)
+		hugetlb_cma_reserve(order);
 }