hugetlb: pass vma into huge_pte_alloc() and huge_pmd_share()

Patch series "hugetlb: Disable huge pmd unshare for uffd-wp", v4.

This series tries to disable huge pmd unshare of hugetlbfs backed memory
for uffd-wp. Although uffd-wp of hugetlbfs is still during rfc stage,
the idea of this series may be needed for multiple tasks (Axel's uffd
minor fault series, and Mike's soft dirty series), so I picked it out
from the larger series.

This patch (of 4):

It is a preparation work to be able to behave differently in the per
architecture huge_pte_alloc() according to different VMA attributes.

Pass it deeper into huge_pmd_share() so that we can avoid the find_vma() call.

[[e-mail]: build fix]
Link: https://lkml.kernel.org/r/20210304164653.GB397383@xz-x1Link: https://lkml.kernel.org/r/[e-mail]

Link: https://lkml.kernel.org/r/[e-mail]
Signed-off-by: Peter Xu <[e-mail]>
Suggested-by: Mike Kravetz <[e-mail]>
Cc: Adam Ruprecht <[e-mail]>
Cc: Alexander Viro <[e-mail]>
Cc: Alexey Dobriyan <[e-mail]>
Cc: Andrea Arcangeli <[e-mail]>
Cc: Anshuman Khandual <[e-mail]>
Cc: Axel Rasmussen <[e-mail]>
Cc: Cannon Matthews <[e-mail]>
Cc: Catalin Marinas <[e-mail]>
Cc: Chinwen Chang <[e-mail]>
Cc: David Rientjes <[e-mail]>
Cc: "Dr . David Alan Gilbert" <[e-mail]>
Cc: Huang Ying <[e-mail]>
Cc: Ingo Molnar <[e-mail]>
Cc: Jann Horn <[e-mail]>
Cc: Jerome Glisse <[e-mail]>
Cc: Kirill A. Shutemov <[e-mail]>
Cc: Lokesh Gidra <[e-mail]>
Cc: "Matthew Wilcox (Oracle)" <[e-mail]>
Cc: Michael Ellerman <[e-mail]>
Cc: "Michal Koutn" <[e-mail]>
Cc: Michel Lespinasse <[e-mail]>
Cc: Mike Rapoport <[e-mail]>
Cc: Mina Almasry <[e-mail]>
Cc: Nicholas Piggin <[e-mail]>
Cc: Oliver Upton <[e-mail]>
Cc: Shaohua Li <[e-mail]>
Cc: Shawn Anastasio <[e-mail]>
Cc: Steven Price <[e-mail]>
Cc: Steven Rostedt <[e-mail]>
Cc: Vlastimil Babka <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

arch/arm64/mm/hugetlbpage.c

···
 		set_pte(ptep, pte);
 }
 
-pte_t *huge_pte_alloc(struct mm_struct *mm,
+pte_t *huge_pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma,
 		      unsigned long addr, unsigned long sz)
 {
 	pgd_t *pgdp;
···
 	} else if (sz == PMD_SIZE) {
 		if (IS_ENABLED(CONFIG_ARCH_WANT_HUGE_PMD_SHARE) &&
 		    pud_none(READ_ONCE(*pudp)))
-			ptep = huge_pmd_share(mm, addr, pudp);
+			ptep = huge_pmd_share(mm, vma, addr, pudp);
 		else
 			ptep = (pte_t *)pmd_alloc(mm, pudp, addr);
 	} else if (sz == (CONT_PMD_SIZE)) {

arch/ia64/mm/hugetlbpage.c

···
 EXPORT_SYMBOL(hpage_shift);
 
 pte_t *
-huge_pte_alloc(struct mm_struct *mm, unsigned long addr, unsigned long sz)
+huge_pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma,
+	       unsigned long addr, unsigned long sz)
 {
 	unsigned long taddr = htlbpage_to_page(addr);
 	pgd_t *pgd;

arch/mips/mm/hugetlbpage.c

···
 #include <asm/tlb.h>
 #include <asm/tlbflush.h>
 
-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 *pgd;
 	p4d_t *p4d;

arch/parisc/mm/hugetlbpage.c

···
 }
 
 
-pte_t *huge_pte_alloc(struct mm_struct *mm,
+pte_t *huge_pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma,
 			unsigned long addr, unsigned long sz)
 {
 	pgd_t *pgd;

arch/powerpc/mm/hugetlbpage.c

···
  * 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;

arch/s390/mm/hugetlbpage.c

···
 	return pte;
 }
 
-pte_t *huge_pte_alloc(struct mm_struct *mm,
+pte_t *huge_pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma,
 			unsigned long addr, unsigned long sz)
 {
 	pgd_t *pgdp;

arch/sh/mm/hugetlbpage.c

···
 #include <asm/tlbflush.h>
 #include <asm/cacheflush.h>
 
-pte_t *huge_pte_alloc(struct mm_struct *mm,
+pte_t *huge_pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma,
 			unsigned long addr, unsigned long sz)
 {
 	pgd_t *pgd;

arch/sparc/mm/hugetlbpage.c

···
 unsigned long pmd_leaf_size(pmd_t pmd) { return 1UL << tte_to_shift(*(pte_t *)&pmd); }
 unsigned long pte_leaf_size(pte_t pte) { return 1UL << tte_to_shift(pte); }
 
-pte_t *huge_pte_alloc(struct mm_struct *mm,
+pte_t *huge_pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma,
 			unsigned long addr, unsigned long sz)
 {
 	pgd_t *pgd;

include/linux/hugetlb.h

···
 extern struct mutex *hugetlb_fault_mutex_table;
 u32 hugetlb_fault_mutex_hash(struct address_space *mapping, pgoff_t idx);
 
-pte_t *huge_pmd_share(struct mm_struct *mm, unsigned long addr, pud_t *pud);
+pte_t *huge_pmd_share(struct mm_struct *mm, struct vm_area_struct *vma,
+		      unsigned long addr, pud_t *pud);
 
 struct address_space *hugetlb_page_mapping_lock_write(struct page *hpage);
 
···
 
 /* arch callbacks */
 
-pte_t *huge_pte_alloc(struct mm_struct *mm,
+pte_t *huge_pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma,
 			unsigned long addr, unsigned long sz);
 pte_t *huge_pte_offset(struct mm_struct *mm,
 		       unsigned long addr, unsigned long sz);

mm/hugetlb.c

···
 		src_pte = huge_pte_offset(src, addr, sz);
 		if (!src_pte)
 			continue;
-		dst_pte = huge_pte_alloc(dst, addr, sz);
+		dst_pte = huge_pte_alloc(dst, vma, addr, sz);
 		if (!dst_pte) {
 			ret = -ENOMEM;
 			break;
···
 	 */
 	mapping = vma->vm_file->f_mapping;
 	i_mmap_lock_read(mapping);
-	ptep = huge_pte_alloc(mm, haddr, huge_page_size(h));
+	ptep = huge_pte_alloc(mm, vma, haddr, huge_page_size(h));
 	if (!ptep) {
 		i_mmap_unlock_read(mapping);
 		return VM_FAULT_OOM;
···
  * if !vma_shareable check at the beginning of the routine. i_mmap_rwsem is
  * only required for subsequent processing.
  */
-pte_t *huge_pmd_share(struct mm_struct *mm, unsigned long addr, pud_t *pud)
+pte_t *huge_pmd_share(struct mm_struct *mm, struct vm_area_struct *vma,
+		      unsigned long addr, pud_t *pud)
 {
-	struct vm_area_struct *vma = find_vma(mm, addr);
 	struct address_space *mapping = vma->vm_file->f_mapping;
 	pgoff_t idx = ((addr - vma->vm_start) >> PAGE_SHIFT) +
 			vma->vm_pgoff;
···
 }
 #define want_pmd_share()	(1)
 #else /* !CONFIG_ARCH_WANT_HUGE_PMD_SHARE */
-pte_t *huge_pmd_share(struct mm_struct *mm, unsigned long addr, pud_t *pud)
+pte_t *huge_pmd_share(struct mm_struct *mm, struct vm_area_struct *vma,
+		      unsigned long addr, pud_t *pud)
 {
 	return NULL;
 }
···
 #endif /* CONFIG_ARCH_WANT_HUGE_PMD_SHARE */
 
 #ifdef CONFIG_ARCH_WANT_GENERAL_HUGETLB
-pte_t *huge_pte_alloc(struct mm_struct *mm,
+pte_t *huge_pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma,
 			unsigned long addr, unsigned long sz)
 {
 	pgd_t *pgd;
···
 		} else {
 			BUG_ON(sz != PMD_SIZE);
 			if (want_pmd_share() && pud_none(*pud))
-				pte = huge_pmd_share(mm, addr, pud);
+				pte = huge_pmd_share(mm, vma, addr, pud);
 			else
 				pte = (pte_t *)pmd_alloc(mm, pud, addr);
 		}

mm/userfaultfd.c

···
 		mutex_lock(&hugetlb_fault_mutex_table[hash]);
 
 		err = -ENOMEM;
-		dst_pte = huge_pte_alloc(dst_mm, dst_addr, vma_hpagesize);
+		dst_pte = huge_pte_alloc(dst_mm, dst_vma, dst_addr, vma_hpagesize);
 		if (!dst_pte) {
 			mutex_unlock(&hugetlb_fault_mutex_table[hash]);
 			i_mmap_unlock_read(mapping);