From 04dd17822334871b23ea2862f7798fb0e0007777 Mon Sep 17 00:00:00 2001
From: hc <hc@nodka.com>
Date: Sat, 11 May 2024 08:53:19 +0000
Subject: [PATCH] change otg to host mode

---
 kernel/arch/powerpc/mm/hugetlbpage.c |  426 ++++++++++++++---------------------------------------
 1 files changed, 113 insertions(+), 313 deletions(-)

diff --git a/kernel/arch/powerpc/mm/hugetlbpage.c b/kernel/arch/powerpc/mm/hugetlbpage.c
index cef0b7e..2514884 100644
--- a/kernel/arch/powerpc/mm/hugetlbpage.c
+++ b/kernel/arch/powerpc/mm/hugetlbpage.c
@@ -15,33 +15,22 @@
 #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 <linux/kmemleak.h>
-#include <asm/pgtable.h>
 #include <asm/pgalloc.h>
 #include <asm/tlb.h>
 #include <asm/setup.h>
 #include <asm/hugetlb.h>
 #include <asm/pte-walk.h>
 
-
-#ifdef CONFIG_HUGETLB_PAGE
-
-#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
-
 bool hugetlb_disabled = false;
 
-unsigned int HPAGE_SHIFT;
-EXPORT_SYMBOL(HPAGE_SHIFT);
-
 #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)
 {
@@ -62,19 +51,24 @@
 	int num_hugepd;
 
 	if (pshift >= pdshift) {
-		cachep = hugepte_cache;
+		cachep = PGT_CACHE(PTE_T_ORDER);
 		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));
+	if (!cachep) {
+		WARN_ONCE(1, "No page table cache created for hugetlb tables");
+		return -ENOMEM;
+	}
+
+	new = kmem_cache_alloc(cachep, pgtable_gfp_flags(mm, GFP_KERNEL));
 
 	BUG_ON(pshift > HUGEPD_SHIFT_MASK);
 	BUG_ON((unsigned long)new & HUGEPD_SHIFT_MASK);
 
-	if (! new)
+	if (!new)
 		return -ENOMEM;
 
 	/*
@@ -94,19 +88,7 @@
 	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) | _PMD_USER |
-					 (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
-		}
+		hugepd_populate(hpdp, new, pshift);
 	}
 	/* If we bailed from the for loop early, an error occurred, clean up */
 	if (i < num_hugepd) {
@@ -124,9 +106,11 @@
  * 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;
+	p4d_t *p4;
 	pud_t *pu;
 	pmd_t *pm;
 	hugepd_t *hpdp = NULL;
@@ -136,20 +120,21 @@
 
 	addr &= ~(sz-1);
 	pg = pgd_offset(mm, addr);
+	p4 = p4d_offset(pg, addr);
 
 #ifdef CONFIG_PPC_BOOK3S_64
 	if (pshift == PGDIR_SHIFT)
 		/* 16GB huge page */
-		return (pte_t *) pg;
+		return (pte_t *) p4;
 	else if (pshift > PUD_SHIFT) {
 		/*
 		 * We need to use hugepd table
 		 */
 		ptl = &mm->page_table_lock;
-		hpdp = (hugepd_t *)pg;
+		hpdp = (hugepd_t *)p4;
 	} else {
 		pdshift = PUD_SHIFT;
-		pu = pud_alloc(mm, pg, addr);
+		pu = pud_alloc(mm, p4, addr);
 		if (!pu)
 			return NULL;
 		if (pshift == PUD_SHIFT)
@@ -174,10 +159,10 @@
 #else
 	if (pshift >= PGDIR_SHIFT) {
 		ptl = &mm->page_table_lock;
-		hpdp = (hugepd_t *)pg;
+		hpdp = (hugepd_t *)p4;
 	} else {
 		pdshift = PUD_SHIFT;
-		pu = pud_alloc(mm, pg, addr);
+		pu = pud_alloc(mm, p4, addr);
 		if (!pu)
 			return NULL;
 		if (pshift >= PUD_SHIFT) {
@@ -195,6 +180,9 @@
 #endif
 	if (!hpdp)
 		return NULL;
+
+	if (IS_ENABLED(CONFIG_PPC_8xx) && pshift < PMD_SHIFT)
+		return pte_alloc_map(mm, (pmd_t *)hpdp, addr);
 
 	BUG_ON(!hugepd_none(*hpdp) && !hugepd_ok(*hpdp));
 
@@ -254,14 +242,14 @@
 	return __alloc_bootmem_huge_page(h);
 }
 
-#if defined(CONFIG_PPC_FSL_BOOK3E) || defined(CONFIG_PPC_8xx)
+#ifndef CONFIG_PPC_BOOK3S_64
 #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];
+	void *ptes[];
 };
 
 static DEFINE_PER_CPU(struct hugepd_freelist *, hugepd_freelist_cur);
@@ -273,7 +261,7 @@
 	unsigned int i;
 
 	for (i = 0; i < batch->index; i++)
-		kmem_cache_free(hugepte_cache, batch->ptes[i]);
+		kmem_cache_free(PGT_CACHE(PTE_T_ORDER), batch->ptes[i]);
 
 	free_page((unsigned long)batch);
 }
@@ -286,7 +274,7 @@
 
 	if (atomic_read(&tlb->mm->mm_users) < 2 ||
 	    mm_is_thread_local(tlb->mm)) {
-		kmem_cache_free(hugepte_cache, hugepte);
+		kmem_cache_free(PGT_CACHE(PTE_T_ORDER), hugepte);
 		put_cpu_var(hugepd_freelist_cur);
 		return;
 	}
@@ -298,7 +286,7 @@
 
 	(*batchp)->ptes[(*batchp)->index++] = hugepte;
 	if ((*batchp)->index == HUGEPD_FREELIST_SIZE) {
-		call_rcu_sched(&(*batchp)->rcu, hugepd_free_rcu_callback);
+		call_rcu(&(*batchp)->rcu, hugepd_free_rcu_callback);
 		*batchp = NULL;
 	}
 	put_cpu_var(hugepd_freelist_cur);
@@ -343,6 +331,29 @@
 				 get_hugepd_cache_index(pdshift - shift));
 }
 
+static void hugetlb_free_pte_range(struct mmu_gather *tlb, pmd_t *pmd,
+				   unsigned long addr, unsigned long end,
+				   unsigned long floor, unsigned long ceiling)
+{
+	unsigned long start = addr;
+	pgtable_t token = pmd_pgtable(*pmd);
+
+	start &= PMD_MASK;
+	if (start < floor)
+		return;
+	if (ceiling) {
+		ceiling &= PMD_MASK;
+		if (!ceiling)
+			return;
+	}
+	if (end - 1 > ceiling - 1)
+		return;
+
+	pmd_clear(pmd);
+	pte_free_tlb(tlb, token, addr);
+	mm_dec_nr_ptes(tlb->mm);
+}
+
 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)
@@ -358,11 +369,17 @@
 		pmd = pmd_offset(pud, addr);
 		next = pmd_addr_end(addr, end);
 		if (!is_hugepd(__hugepd(pmd_val(*pmd)))) {
+			if (pmd_none_or_clear_bad(pmd))
+				continue;
+
 			/*
 			 * if it is not hugepd pointer, we should already find
 			 * it cleared.
 			 */
-			WARN_ON(!pmd_none_or_clear_bad(pmd));
+			WARN_ON(!IS_ENABLED(CONFIG_PPC_8xx));
+
+			hugetlb_free_pte_range(tlb, pmd, addr, end, floor, ceiling);
+
 			continue;
 		}
 		/*
@@ -396,7 +413,7 @@
 	mm_dec_nr_pmds(tlb->mm);
 }
 
-static void hugetlb_free_pud_range(struct mmu_gather *tlb, pgd_t *pgd,
+static void hugetlb_free_pud_range(struct mmu_gather *tlb, p4d_t *p4d,
 				   unsigned long addr, unsigned long end,
 				   unsigned long floor, unsigned long ceiling)
 {
@@ -406,7 +423,7 @@
 
 	start = addr;
 	do {
-		pud = pud_offset(pgd, addr);
+		pud = pud_offset(p4d, addr);
 		next = pud_addr_end(addr, end);
 		if (!is_hugepd(__hugepd(pud_val(*pud)))) {
 			if (pud_none_or_clear_bad(pud))
@@ -441,8 +458,8 @@
 	if (end - 1 > ceiling - 1)
 		return;
 
-	pud = pud_offset(pgd, start);
-	pgd_clear(pgd);
+	pud = pud_offset(p4d, start);
+	p4d_clear(p4d);
 	pud_free_tlb(tlb, pud, start);
 	mm_dec_nr_puds(tlb->mm);
 }
@@ -455,6 +472,7 @@
 			    unsigned long floor, unsigned long ceiling)
 {
 	pgd_t *pgd;
+	p4d_t *p4d;
 	unsigned long next;
 
 	/*
@@ -477,10 +495,11 @@
 	do {
 		next = pgd_addr_end(addr, end);
 		pgd = pgd_offset(tlb->mm, addr);
+		p4d = p4d_offset(pgd, addr);
 		if (!is_hugepd(__hugepd(pgd_val(*pgd)))) {
-			if (pgd_none_or_clear_bad(pgd))
+			if (p4d_none_or_clear_bad(p4d))
 				continue;
-			hugetlb_free_pud_range(tlb, pgd, addr, next, floor, ceiling);
+			hugetlb_free_pud_range(tlb, p4d, addr, next, floor, ceiling);
 		} else {
 			unsigned long more;
 			/*
@@ -493,7 +512,7 @@
 			if (more > next)
 				next = more;
 
-			free_hugepd_range(tlb, (hugepd_t *)pgd, PGDIR_SHIFT,
+			free_hugepd_range(tlb, (hugepd_t *)p4d, PGDIR_SHIFT,
 					  addr, next, floor, ceiling);
 		}
 	} while (addr = next, addr != end);
@@ -536,30 +555,6 @@
 	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,
@@ -579,91 +574,48 @@
 
 unsigned long vma_mmu_pagesize(struct vm_area_struct *vma)
 {
-#ifdef CONFIG_PPC_MM_SLICES
 	/* With radix we don't use slice, so derive it from vma*/
-	if (!radix_enabled()) {
+	if (IS_ENABLED(CONFIG_PPC_MM_SLICES) && !radix_enabled()) {
 		unsigned int psize = get_slice_psize(vma->vm_mm, vma->vm_start);
 
 		return 1UL << mmu_psize_to_shift(psize);
 	}
-#endif
 	return vma_kernel_pagesize(vma);
 }
 
-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 and 1G
-	 * Hash: 16M and 16G
-	 */
-	if (radix_enabled()) {
-		if (mmu_psize != MMU_PAGE_2M && 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;
+	return true;
+}
+
+static int __init add_huge_page_size(unsigned long long size)
+{
+	int shift = __ffs(size);
+
+	if (!arch_hugetlb_valid_size((unsigned long)size))
+		return -EINVAL;
 
 	hugetlb_add_hstate(shift - PAGE_SHIFT);
-
 	return 0;
 }
 
-static int __init hugepage_setup_sz(char *str)
-{
-	unsigned long long size;
-
-	size = memparse(str, &str);
-
-	if (add_huge_page_size(size) != 0) {
-		hugetlb_bad_size();
-		pr_err("Invalid huge page size specified(%llu)\n", size);
-	}
-
-	return 1;
-}
-__setup("hugepagesz=", hugepage_setup_sz);
-
-struct kmem_cache *hugepte_cache;
 static int __init hugetlbpage_init(void)
 {
+	bool configured = false;
 	int psize;
 
 	if (hugetlb_disabled) {
@@ -671,10 +623,10 @@
 		return 0;
 	}
 
-#if !defined(CONFIG_PPC_FSL_BOOK3E) && !defined(CONFIG_PPC_8xx)
-	if (!radix_enabled() && !mmu_has_feature(MMU_FTR_16M_PAGE))
+	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;
@@ -708,44 +660,23 @@
 		 * 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__);
-
+		if (pdshift > shift) {
+			if (!IS_ENABLED(CONFIG_PPC_8xx))
+				pgtable_cache_add(pdshift - shift);
+		} else if (IS_ENABLED(CONFIG_PPC_FSL_BOOK3E) ||
+			   IS_ENABLED(CONFIG_PPC_8xx)) {
+			pgtable_cache_add(PTE_T_ORDER);
 		}
-#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) {
+		if (IS_ENABLED(CONFIG_HUGETLB_PAGE_SIZE_VARIABLE))
+			hugetlbpage_init_default();
+	} else
+		pr_info("Failed to initialize. Disabling HugeTLB");
+
 	return 0;
 }
 
@@ -758,7 +689,7 @@
 
 	BUG_ON(!PageCompound(page));
 
-	for (i = 0; i < (1UL << compound_order(page)); i++) {
+	for (i = 0; i < compound_nr(page); i++) {
 		if (!PageHighMem(page)) {
 			__flush_dcache_icache(page_address(page+i));
 		} else {
@@ -769,151 +700,20 @@
 	}
 }
 
-#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->irq_soft_mask = IRQS_ENABLED
- */
-pte_t *__find_linux_pte(pgd_t *pgdir, unsigned long ea,
-			bool *is_thp, unsigned *hpage_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 (hpage_shift)
-		*hpage_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);
+		order = mmu_psize_to_shift(MMU_PAGE_16G) - PAGE_SHIFT;
 
-		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 (order) {
+		VM_WARN_ON(order < MAX_ORDER);
+		hugetlb_cma_reserve(order);
 	}
-	if (!hpdp)
-		return NULL;
-
-	ret_pte = hugepte_offset(*hpdp, ea, pdshift);
-	pdshift = hugepd_shift(*hpdp);
-out:
-	if (hpage_shift)
-		*hpage_shift = pdshift;
-	return ret_pte;
-}
-EXPORT_SYMBOL_GPL(__find_linux_pte);
-
-int gup_hugepte(pte_t *ptep, unsigned long sz, unsigned long addr,
-		unsigned long end, int write, struct page **pages, int *nr)
-{
-	unsigned long pte_end;
-	struct page *head, *page;
-	pte_t pte;
-	int refs;
-
-	pte_end = (addr + sz) & ~(sz-1);
-	if (pte_end < end)
-		end = pte_end;
-
-	pte = READ_ONCE(*ptep);
-
-	if (!pte_access_permitted(pte, write))
-		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;
 }

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