[PATCH v11 00/13] huge vmalloc mappings

[PATCH v11 00/13] huge vmalloc mappings

[Nicholas Piggin]

I think I ended up implementing all Christoph's comments because
they turned out better in the end. Cleanups coming in another
series though.

Thanks,
Nick

Since v10:
- Fixed code style, most > 80 colums, tweak patch titles, etc [thanks Christoph]
- Made huge vmalloc code and data structure compile away if unselected
  [Christoph]
- Archs only have to provide arch_vmap_p?d_supported for levels they
  implement [Christoph]

Since v9:
- Fixed intermediate build breakage on x86-32 !PAE [thanks Ding]
- Fixed small page fallback case vm_struct double-free [thanks Ding]

Since v8:
- Fixed nommu compile.
- Added Kconfig option help text
- Added VM_NOHUGE which should help archs implement it [suggested by Rick]

Since v7:
- Rebase, added some acks, compile fix
- Removed "order=" from vmallocinfo, it's a bit confusing (nr_pages
  is in small page size for compatibility).
- Added arch_vmap_pmd_supported() test before starting to allocate
  the large page, rather than only testing it when doing the map, to
  avoid unsupported configs trying to allocate huge pages for no
  reason.

Since v6:
- Fixed a false positive warning introduced in patch 2, found by
  kbuild test robot.

Since v5:
- Split arch changes out better and make the constant folding work
- Avoid most of the 80 column wrap, fix a reference to lib/ioremap.c
- Fix compile error on some archs

Since v4:
- Fixed an off-by-page-order bug in v4
- Several minor cleanups.
- Added page order to /proc/vmallocinfo
- Added hugepage to alloc_large_system_hage output.
- Made an architecture config option, powerpc only for now.

Since v3:
- Fixed an off-by-one bug in a loop
- Fix !CONFIG_HAVE_ARCH_HUGE_VMAP build fail

Nicholas Piggin (13):
  mm/vmalloc: fix HUGE_VMAP regression by enabling huge pages in
    vmalloc_to_page
  mm: apply_to_pte_range warn and fail if a large pte is encountered
  mm/vmalloc: rename vmap_*_range vmap_pages_*_range
  mm/ioremap: rename ioremap_*_range to vmap_*_range
  mm: HUGE_VMAP arch support cleanup
  powerpc: inline huge vmap supported functions
  arm64: inline huge vmap supported functions
  x86: inline huge vmap supported functions
  mm/vmalloc: provide fallback arch huge vmap support functions
  mm: Move vmap_range from mm/ioremap.c to mm/vmalloc.c
  mm/vmalloc: add vmap_range_noflush variant
  mm/vmalloc: Hugepage vmalloc mappings
  powerpc/64s/radix: Enable huge vmalloc mappings

 .../admin-guide/kernel-parameters.txt         |   2 +
 arch/Kconfig                                  |  11 +
 arch/arm64/include/asm/vmalloc.h              |  24 +
 arch/arm64/mm/mmu.c                           |  26 -
 arch/powerpc/Kconfig                          |   1 +
 arch/powerpc/include/asm/vmalloc.h            |  20 +
 arch/powerpc/kernel/module.c                  |  21 +-
 arch/powerpc/mm/book3s64/radix_pgtable.c      |  21 -
 arch/x86/include/asm/vmalloc.h                |  20 +
 arch/x86/mm/ioremap.c                         |  19 -
 arch/x86/mm/pgtable.c                         |  13 -
 include/linux/io.h                            |   9 -
 include/linux/vmalloc.h                       |  46 ++
 init/main.c                                   |   1 -
 mm/ioremap.c                                  | 225 +-------
 mm/memory.c                                   |  66 ++-
 mm/page_alloc.c                               |   5 +-
 mm/vmalloc.c                                  | 484 +++++++++++++++---
 18 files changed, 614 insertions(+), 400 deletions(-)

-- 
2.23.0

[PATCH v11 01/13] mm/vmalloc: fix HUGE_VMAP regression by enabling huge pages in vmalloc_to_page

[Nicholas Piggin]

vmalloc_to_page returns NULL for addresses mapped by larger pages[*].
Whether or not a vmap is huge depends on the architecture details,
alignments, boot options, etc., which the caller can not be expected
to know. Therefore HUGE_VMAP is a regression for vmalloc_to_page.

This change teaches vmalloc_to_page about larger pages, and returns
the struct page that corresponds to the offset within the large page.
This makes the API agnostic to mapping implementation details.

[*] As explained by commit 029c54b095995 ("mm/vmalloc.c: huge-vmap:
    fail gracefully on unexpected huge vmap mappings")

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 mm/vmalloc.c | 41 ++++++++++++++++++++++++++---------------
 1 file changed, 26 insertions(+), 15 deletions(-)

diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index e6f352bf0498..62372f9e0167 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -34,7 +34,7 @@
 #include <linux/bitops.h>
 #include <linux/rbtree_augmented.h>
 #include <linux/overflow.h>
-
+#include <linux/pgtable.h>
 #include <linux/uaccess.h>
 #include <asm/tlbflush.h>
 #include <asm/shmparam.h>
@@ -343,7 +343,9 @@ int is_vmalloc_or_module_addr(const void *x)
 }
 
 /*
- * Walk a vmap address to the struct page it maps.
+ * Walk a vmap address to the struct page it maps. Huge vmap mappings will
+ * return the tail page that corresponds to the base page address, which
+ * matches small vmap mappings.
  */
 struct page *vmalloc_to_page(const void *vmalloc_addr)
 {
@@ -363,25 +365,33 @@ struct page *vmalloc_to_page(const void *vmalloc_addr)
 
 	if (pgd_none(*pgd))
 		return NULL;
+	if (WARN_ON_ONCE(pgd_leaf(*pgd)))
+		return NULL; /* XXX: no allowance for huge pgd */
+	if (WARN_ON_ONCE(pgd_bad(*pgd)))
+		return NULL;
+
 	p4d = p4d_offset(pgd, addr);
 	if (p4d_none(*p4d))
 		return NULL;
-	pud = pud_offset(p4d, addr);
+	if (p4d_leaf(*p4d))
+		return p4d_page(*p4d) + ((addr & ~P4D_MASK) >> PAGE_SHIFT);
+	if (WARN_ON_ONCE(p4d_bad(*p4d)))
+		return NULL;
 
-	/*
-	 * Don't dereference bad PUD or PMD (below) entries. This will also
-	 * identify huge mappings, which we may encounter on architectures
-	 * that define CONFIG_HAVE_ARCH_HUGE_VMAP=y. Such regions will be
-	 * identified as vmalloc addresses by is_vmalloc_addr(), but are
-	 * not [unambiguously] associated with a struct page, so there is
-	 * no correct value to return for them.
-	 */
-	WARN_ON_ONCE(pud_bad(*pud));
-	if (pud_none(*pud) || pud_bad(*pud))
+	pud = pud_offset(p4d, addr);
+	if (pud_none(*pud))
+		return NULL;
+	if (pud_leaf(*pud))
+		return pud_page(*pud) + ((addr & ~PUD_MASK) >> PAGE_SHIFT);
+	if (WARN_ON_ONCE(pud_bad(*pud)))
 		return NULL;
+
 	pmd = pmd_offset(pud, addr);
-	WARN_ON_ONCE(pmd_bad(*pmd));
-	if (pmd_none(*pmd) || pmd_bad(*pmd))
+	if (pmd_none(*pmd))
+		return NULL;
+	if (pmd_leaf(*pmd))
+		return pmd_page(*pmd) + ((addr & ~PMD_MASK) >> PAGE_SHIFT);
+	if (WARN_ON_ONCE(pmd_bad(*pmd)))
 		return NULL;
 
 	ptep = pte_offset_map(pmd, addr);
@@ -389,6 +399,7 @@ struct page *vmalloc_to_page(const void *vmalloc_addr)
 	if (pte_present(pte))
 		page = pte_page(pte);
 	pte_unmap(ptep);
+
 	return page;
 }
 EXPORT_SYMBOL(vmalloc_to_page);
-- 
2.23.0

[PATCH v11 02/13] mm: apply_to_pte_range warn and fail if a large pte is encountered

[Nicholas Piggin]

apply_to_pte_range might mistake a large pte for bad, or treat it as a
page table, resulting in a crash or corruption. Add a test to warn and
return error if large entries are found.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 mm/memory.c | 66 +++++++++++++++++++++++++++++++++++++++--------------
 1 file changed, 49 insertions(+), 17 deletions(-)

diff --git a/mm/memory.c b/mm/memory.c
index feff48e1465a..672e39a72788 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -2440,13 +2440,21 @@ static int apply_to_pmd_range(struct mm_struct *mm, pud_t *pud,
 	}
 	do {
 		next = pmd_addr_end(addr, end);
-		if (create || !pmd_none_or_clear_bad(pmd)) {
-			err = apply_to_pte_range(mm, pmd, addr, next, fn, data,
-						 create, mask);
-			if (err)
-				break;
+		if (pmd_none(*pmd) && !create)
+			continue;
+		if (WARN_ON_ONCE(pmd_leaf(*pmd)))
+			return -EINVAL;
+		if (!pmd_none(*pmd) && WARN_ON_ONCE(pmd_bad(*pmd))) {
+			if (!create)
+				continue;
+			pmd_clear_bad(pmd);
 		}
+		err = apply_to_pte_range(mm, pmd, addr, next,
+					 fn, data, create, mask);
+		if (err)
+			break;
 	} while (pmd++, addr = next, addr != end);
+
 	return err;
 }
 
@@ -2468,13 +2476,21 @@ static int apply_to_pud_range(struct mm_struct *mm, p4d_t *p4d,
 	}
 	do {
 		next = pud_addr_end(addr, end);
-		if (create || !pud_none_or_clear_bad(pud)) {
-			err = apply_to_pmd_range(mm, pud, addr, next, fn, data,
-						 create, mask);
-			if (err)
-				break;
+		if (pud_none(*pud) && !create)
+			continue;
+		if (WARN_ON_ONCE(pud_leaf(*pud)))
+			return -EINVAL;
+		if (!pud_none(*pud) && WARN_ON_ONCE(pud_bad(*pud))) {
+			if (!create)
+				continue;
+			pud_clear_bad(pud);
 		}
+		err = apply_to_pmd_range(mm, pud, addr, next,
+					 fn, data, create, mask);
+		if (err)
+			break;
 	} while (pud++, addr = next, addr != end);
+
 	return err;
 }
 
@@ -2496,13 +2512,21 @@ static int apply_to_p4d_range(struct mm_struct *mm, pgd_t *pgd,
 	}
 	do {
 		next = p4d_addr_end(addr, end);
-		if (create || !p4d_none_or_clear_bad(p4d)) {
-			err = apply_to_pud_range(mm, p4d, addr, next, fn, data,
-						 create, mask);
-			if (err)
-				break;
+		if (p4d_none(*p4d) && !create)
+			continue;
+		if (WARN_ON_ONCE(p4d_leaf(*p4d)))
+			return -EINVAL;
+		if (!p4d_none(*p4d) && WARN_ON_ONCE(p4d_bad(*p4d))) {
+			if (!create)
+				continue;
+			p4d_clear_bad(p4d);
 		}
+		err = apply_to_pud_range(mm, p4d, addr, next,
+					 fn, data, create, mask);
+		if (err)
+			break;
 	} while (p4d++, addr = next, addr != end);
+
 	return err;
 }
 
@@ -2522,9 +2546,17 @@ static int __apply_to_page_range(struct mm_struct *mm, unsigned long addr,
 	pgd = pgd_offset(mm, addr);
 	do {
 		next = pgd_addr_end(addr, end);
-		if (!create && pgd_none_or_clear_bad(pgd))
+		if (pgd_none(*pgd) && !create)
 			continue;
-		err = apply_to_p4d_range(mm, pgd, addr, next, fn, data, create, &mask);
+		if (WARN_ON_ONCE(pgd_leaf(*pgd)))
+			return -EINVAL;
+		if (!pgd_none(*pgd) && WARN_ON_ONCE(pgd_bad(*pgd))) {
+			if (!create)
+				continue;
+			pgd_clear_bad(pgd);
+		}
+		err = apply_to_p4d_range(mm, pgd, addr, next,
+					 fn, data, create, &mask);
 		if (err)
 			break;
 	} while (pgd++, addr = next, addr != end);
-- 
2.23.0

[PATCH v11 03/13] mm/vmalloc: rename vmap_*_range vmap_pages_*_range

[Nicholas Piggin]

The vmalloc mapper operates on a struct page * array rather than a
linear physical address, re-name it to make this distinction clear.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 mm/vmalloc.c | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index 62372f9e0167..7f2f36116980 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -189,7 +189,7 @@ void unmap_kernel_range_noflush(unsigned long start, unsigned long size)
 		arch_sync_kernel_mappings(start, end);
 }
 
-static int vmap_pte_range(pmd_t *pmd, unsigned long addr,
+static int vmap_pages_pte_range(pmd_t *pmd, unsigned long addr,
 		unsigned long end, pgprot_t prot, struct page **pages, int *nr,
 		pgtbl_mod_mask *mask)
 {
@@ -217,7 +217,7 @@ static int vmap_pte_range(pmd_t *pmd, unsigned long addr,
 	return 0;
 }
 
-static int vmap_pmd_range(pud_t *pud, unsigned long addr,
+static int vmap_pages_pmd_range(pud_t *pud, unsigned long addr,
 		unsigned long end, pgprot_t prot, struct page **pages, int *nr,
 		pgtbl_mod_mask *mask)
 {
@@ -229,13 +229,13 @@ static int vmap_pmd_range(pud_t *pud, unsigned long addr,
 		return -ENOMEM;
 	do {
 		next = pmd_addr_end(addr, end);
-		if (vmap_pte_range(pmd, addr, next, prot, pages, nr, mask))
+		if (vmap_pages_pte_range(pmd, addr, next, prot, pages, nr, mask))
 			return -ENOMEM;
 	} while (pmd++, addr = next, addr != end);
 	return 0;
 }
 
-static int vmap_pud_range(p4d_t *p4d, unsigned long addr,
+static int vmap_pages_pud_range(p4d_t *p4d, unsigned long addr,
 		unsigned long end, pgprot_t prot, struct page **pages, int *nr,
 		pgtbl_mod_mask *mask)
 {
@@ -247,13 +247,13 @@ static int vmap_pud_range(p4d_t *p4d, unsigned long addr,
 		return -ENOMEM;
 	do {
 		next = pud_addr_end(addr, end);
-		if (vmap_pmd_range(pud, addr, next, prot, pages, nr, mask))
+		if (vmap_pages_pmd_range(pud, addr, next, prot, pages, nr, mask))
 			return -ENOMEM;
 	} while (pud++, addr = next, addr != end);
 	return 0;
 }
 
-static int vmap_p4d_range(pgd_t *pgd, unsigned long addr,
+static int vmap_pages_p4d_range(pgd_t *pgd, unsigned long addr,
 		unsigned long end, pgprot_t prot, struct page **pages, int *nr,
 		pgtbl_mod_mask *mask)
 {
@@ -265,7 +265,7 @@ static int vmap_p4d_range(pgd_t *pgd, unsigned long addr,
 		return -ENOMEM;
 	do {
 		next = p4d_addr_end(addr, end);
-		if (vmap_pud_range(p4d, addr, next, prot, pages, nr, mask))
+		if (vmap_pages_pud_range(p4d, addr, next, prot, pages, nr, mask))
 			return -ENOMEM;
 	} while (p4d++, addr = next, addr != end);
 	return 0;
@@ -306,7 +306,7 @@ int map_kernel_range_noflush(unsigned long addr, unsigned long size,
 		next = pgd_addr_end(addr, end);
 		if (pgd_bad(*pgd))
 			mask |= PGTBL_PGD_MODIFIED;
-		err = vmap_p4d_range(pgd, addr, next, prot, pages, &nr, &mask);
+		err = vmap_pages_p4d_range(pgd, addr, next, prot, pages, &nr, &mask);
 		if (err)
 			return err;
 	} while (pgd++, addr = next, addr != end);
-- 
2.23.0

[PATCH v11 04/13] mm/ioremap: rename ioremap_*_range to vmap_*_range

[Nicholas Piggin]

This will be used as a generic kernel virtual mapping function, so
re-name it in preparation.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 mm/ioremap.c | 64 +++++++++++++++++++++++++++-------------------------
 1 file changed, 33 insertions(+), 31 deletions(-)

diff --git a/mm/ioremap.c b/mm/ioremap.c
index 5fa1ab41d152..3f4d36f9745a 100644
--- a/mm/ioremap.c
+++ b/mm/ioremap.c
@@ -61,9 +61,9 @@ static inline int ioremap_pud_enabled(void) { return 0; }
 static inline int ioremap_pmd_enabled(void) { return 0; }
 #endif	/* CONFIG_HAVE_ARCH_HUGE_VMAP */
 
-static int ioremap_pte_range(pmd_t *pmd, unsigned long addr,
-		unsigned long end, phys_addr_t phys_addr, pgprot_t prot,
-		pgtbl_mod_mask *mask)
+static int vmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
+			phys_addr_t phys_addr, pgprot_t prot,
+			pgtbl_mod_mask *mask)
 {
 	pte_t *pte;
 	u64 pfn;
@@ -81,9 +81,8 @@ static int ioremap_pte_range(pmd_t *pmd, unsigned long addr,
 	return 0;
 }
 
-static int ioremap_try_huge_pmd(pmd_t *pmd, unsigned long addr,
-				unsigned long end, phys_addr_t phys_addr,
-				pgprot_t prot)
+static int vmap_try_huge_pmd(pmd_t *pmd, unsigned long addr, unsigned long end,
+			phys_addr_t phys_addr, pgprot_t prot)
 {
 	if (!ioremap_pmd_enabled())
 		return 0;
@@ -103,9 +102,9 @@ static int ioremap_try_huge_pmd(pmd_t *pmd, unsigned long addr,
 	return pmd_set_huge(pmd, phys_addr, prot);
 }
 
-static inline int ioremap_pmd_range(pud_t *pud, unsigned long addr,
-		unsigned long end, phys_addr_t phys_addr, pgprot_t prot,
-		pgtbl_mod_mask *mask)
+static int vmap_pmd_range(pud_t *pud, unsigned long addr, unsigned long end,
+			phys_addr_t phys_addr, pgprot_t prot,
+			pgtbl_mod_mask *mask)
 {
 	pmd_t *pmd;
 	unsigned long next;
@@ -116,20 +115,19 @@ static inline int ioremap_pmd_range(pud_t *pud, unsigned long addr,
 	do {
 		next = pmd_addr_end(addr, end);
 
-		if (ioremap_try_huge_pmd(pmd, addr, next, phys_addr, prot)) {
+		if (vmap_try_huge_pmd(pmd, addr, next, phys_addr, prot)) {
 			*mask |= PGTBL_PMD_MODIFIED;
 			continue;
 		}
 
-		if (ioremap_pte_range(pmd, addr, next, phys_addr, prot, mask))
+		if (vmap_pte_range(pmd, addr, next, phys_addr, prot, mask))
 			return -ENOMEM;
 	} while (pmd++, phys_addr += (next - addr), addr = next, addr != end);
 	return 0;
 }
 
-static int ioremap_try_huge_pud(pud_t *pud, unsigned long addr,
-				unsigned long end, phys_addr_t phys_addr,
-				pgprot_t prot)
+static int vmap_try_huge_pud(pud_t *pud, unsigned long addr, unsigned long end,
+			phys_addr_t phys_addr, pgprot_t prot)
 {
 	if (!ioremap_pud_enabled())
 		return 0;
@@ -149,9 +147,9 @@ static int ioremap_try_huge_pud(pud_t *pud, unsigned long addr,
 	return pud_set_huge(pud, phys_addr, prot);
 }
 
-static inline int ioremap_pud_range(p4d_t *p4d, unsigned long addr,
-		unsigned long end, phys_addr_t phys_addr, pgprot_t prot,
-		pgtbl_mod_mask *mask)
+static int vmap_pud_range(p4d_t *p4d, unsigned long addr, unsigned long end,
+			phys_addr_t phys_addr, pgprot_t prot,
+			pgtbl_mod_mask *mask)
 {
 	pud_t *pud;
 	unsigned long next;
@@ -162,20 +160,19 @@ static inline int ioremap_pud_range(p4d_t *p4d, unsigned long addr,
 	do {
 		next = pud_addr_end(addr, end);
 
-		if (ioremap_try_huge_pud(pud, addr, next, phys_addr, prot)) {
+		if (vmap_try_huge_pud(pud, addr, next, phys_addr, prot)) {
 			*mask |= PGTBL_PUD_MODIFIED;
 			continue;
 		}
 
-		if (ioremap_pmd_range(pud, addr, next, phys_addr, prot, mask))
+		if (vmap_pmd_range(pud, addr, next, phys_addr, prot, mask))
 			return -ENOMEM;
 	} while (pud++, phys_addr += (next - addr), addr = next, addr != end);
 	return 0;
 }
 
-static int ioremap_try_huge_p4d(p4d_t *p4d, unsigned long addr,
-				unsigned long end, phys_addr_t phys_addr,
-				pgprot_t prot)
+static int vmap_try_huge_p4d(p4d_t *p4d, unsigned long addr, unsigned long end,
+			phys_addr_t phys_addr, pgprot_t prot)
 {
 	if (!ioremap_p4d_enabled())
 		return 0;
@@ -195,9 +192,9 @@ static int ioremap_try_huge_p4d(p4d_t *p4d, unsigned long addr,
 	return p4d_set_huge(p4d, phys_addr, prot);
 }
 
-static inline int ioremap_p4d_range(pgd_t *pgd, unsigned long addr,
-		unsigned long end, phys_addr_t phys_addr, pgprot_t prot,
-		pgtbl_mod_mask *mask)
+static int vmap_p4d_range(pgd_t *pgd, unsigned long addr, unsigned long end,
+			phys_addr_t phys_addr, pgprot_t prot,
+			pgtbl_mod_mask *mask)
 {
 	p4d_t *p4d;
 	unsigned long next;
@@ -208,19 +205,19 @@ static inline int ioremap_p4d_range(pgd_t *pgd, unsigned long addr,
 	do {
 		next = p4d_addr_end(addr, end);
 
-		if (ioremap_try_huge_p4d(p4d, addr, next, phys_addr, prot)) {
+		if (vmap_try_huge_p4d(p4d, addr, next, phys_addr, prot)) {
 			*mask |= PGTBL_P4D_MODIFIED;
 			continue;
 		}
 
-		if (ioremap_pud_range(p4d, addr, next, phys_addr, prot, mask))
+		if (vmap_pud_range(p4d, addr, next, phys_addr, prot, mask))
 			return -ENOMEM;
 	} while (p4d++, phys_addr += (next - addr), addr = next, addr != end);
 	return 0;
 }
 
-int ioremap_page_range(unsigned long addr,
-		       unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
+static int vmap_range(unsigned long addr, unsigned long end,
+			phys_addr_t phys_addr, pgprot_t prot)
 {
 	pgd_t *pgd;
 	unsigned long start;
@@ -235,8 +232,7 @@ int ioremap_page_range(unsigned long addr,
 	pgd = pgd_offset_k(addr);
 	do {
 		next = pgd_addr_end(addr, end);
-		err = ioremap_p4d_range(pgd, addr, next, phys_addr, prot,
-					&mask);
+		err = vmap_p4d_range(pgd, addr, next, phys_addr, prot, &mask);
 		if (err)
 			break;
 	} while (pgd++, phys_addr += (next - addr), addr = next, addr != end);
@@ -249,6 +245,12 @@ int ioremap_page_range(unsigned long addr,
 	return err;
 }
 
+int ioremap_page_range(unsigned long addr,
+		       unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
+{
+	return vmap_range(addr, end, phys_addr, prot);
+}
+
 #ifdef CONFIG_GENERIC_IOREMAP
 void __iomem *ioremap_prot(phys_addr_t addr, size_t size, unsigned long prot)
 {
-- 
2.23.0

[PATCH v11 05/13] mm: HUGE_VMAP arch support cleanup

[Nicholas Piggin]

This changes the awkward approach where architectures provide init
functions to determine which levels they can provide large mappings for,
to one where the arch is queried for each call.

This removes code and indirection, and allows constant-folding of dead
code for unsupported levels.

This also adds a prot argument to the arch query. This is unused
currently but could help with some architectures (e.g., some powerpc
processors can't map uncacheable memory with large pages).

Cc: linuxppc-dev@lists.ozlabs.org
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: x86@kernel.org
Cc: "H. Peter Anvin" <hpa@zytor.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com> [arm64]
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 arch/arm64/include/asm/vmalloc.h         |  8 ++
 arch/arm64/mm/mmu.c                      | 10 +--
 arch/powerpc/include/asm/vmalloc.h       |  8 ++
 arch/powerpc/mm/book3s64/radix_pgtable.c |  8 +-
 arch/x86/include/asm/vmalloc.h           |  7 ++
 arch/x86/mm/ioremap.c                    | 12 +--
 include/linux/io.h                       |  9 ---
 include/linux/vmalloc.h                  |  6 ++
 init/main.c                              |  1 -
 mm/ioremap.c                             | 94 ++++++++++--------------
 10 files changed, 85 insertions(+), 78 deletions(-)

diff --git a/arch/arm64/include/asm/vmalloc.h b/arch/arm64/include/asm/vmalloc.h
index 2ca708ab9b20..597b40405319 100644
--- a/arch/arm64/include/asm/vmalloc.h
+++ b/arch/arm64/include/asm/vmalloc.h
@@ -1,4 +1,12 @@
 #ifndef _ASM_ARM64_VMALLOC_H
 #define _ASM_ARM64_VMALLOC_H
 
+#include <asm/page.h>
+
+#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
+bool arch_vmap_p4d_supported(pgprot_t prot);
+bool arch_vmap_pud_supported(pgprot_t prot);
+bool arch_vmap_pmd_supported(pgprot_t prot);
+#endif
+
 #endif /* _ASM_ARM64_VMALLOC_H */
diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
index ae0c3d023824..1613d290cbd1 100644
--- a/arch/arm64/mm/mmu.c
+++ b/arch/arm64/mm/mmu.c
@@ -1313,12 +1313,12 @@ void *__init fixmap_remap_fdt(phys_addr_t dt_phys, int *size, pgprot_t prot)
 	return dt_virt;
 }
 
-int __init arch_ioremap_p4d_supported(void)
+bool arch_vmap_p4d_supported(pgprot_t prot)
 {
-	return 0;
+	return false;
 }
 
-int __init arch_ioremap_pud_supported(void)
+bool arch_vmap_pud_supported(pgprot_t prot)
 {
 	/*
 	 * Only 4k granule supports level 1 block mappings.
@@ -1328,9 +1328,9 @@ int __init arch_ioremap_pud_supported(void)
 	       !IS_ENABLED(CONFIG_PTDUMP_DEBUGFS);
 }
 
-int __init arch_ioremap_pmd_supported(void)
+bool arch_vmap_pmd_supported(pgprot_t prot)
 {
-	/* See arch_ioremap_pud_supported() */
+	/* See arch_vmap_pud_supported() */
 	return !IS_ENABLED(CONFIG_PTDUMP_DEBUGFS);
 }
 
diff --git a/arch/powerpc/include/asm/vmalloc.h b/arch/powerpc/include/asm/vmalloc.h
index b992dfaaa161..105abb73f075 100644
--- a/arch/powerpc/include/asm/vmalloc.h
+++ b/arch/powerpc/include/asm/vmalloc.h
@@ -1,4 +1,12 @@
 #ifndef _ASM_POWERPC_VMALLOC_H
 #define _ASM_POWERPC_VMALLOC_H
 
+#include <asm/page.h>
+
+#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
+bool arch_vmap_p4d_supported(pgprot_t prot);
+bool arch_vmap_pud_supported(pgprot_t prot);
+bool arch_vmap_pmd_supported(pgprot_t prot);
+#endif
+
 #endif /* _ASM_POWERPC_VMALLOC_H */
diff --git a/arch/powerpc/mm/book3s64/radix_pgtable.c b/arch/powerpc/mm/book3s64/radix_pgtable.c
index 98f0b243c1ab..743807fc210f 100644
--- a/arch/powerpc/mm/book3s64/radix_pgtable.c
+++ b/arch/powerpc/mm/book3s64/radix_pgtable.c
@@ -1082,13 +1082,13 @@ void radix__ptep_modify_prot_commit(struct vm_area_struct *vma,
 	set_pte_at(mm, addr, ptep, pte);
 }
 
-int __init arch_ioremap_pud_supported(void)
+bool arch_vmap_pud_supported(pgprot_t prot)
 {
 	/* HPT does not cope with large pages in the vmalloc area */
 	return radix_enabled();
 }
 
-int __init arch_ioremap_pmd_supported(void)
+bool arch_vmap_pmd_supported(pgprot_t prot)
 {
 	return radix_enabled();
 }
@@ -1182,7 +1182,7 @@ int pmd_free_pte_page(pmd_t *pmd, unsigned long addr)
 	return 1;
 }
 
-int __init arch_ioremap_p4d_supported(void)
+bool arch_vmap_p4d_supported(pgprot_t prot)
 {
-	return 0;
+	return false;
 }
diff --git a/arch/x86/include/asm/vmalloc.h b/arch/x86/include/asm/vmalloc.h
index 29837740b520..094ea2b565f3 100644
--- a/arch/x86/include/asm/vmalloc.h
+++ b/arch/x86/include/asm/vmalloc.h
@@ -1,6 +1,13 @@
 #ifndef _ASM_X86_VMALLOC_H
 #define _ASM_X86_VMALLOC_H
 
+#include <asm/page.h>
 #include <asm/pgtable_areas.h>
 
+#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
+bool arch_vmap_p4d_supported(pgprot_t prot);
+bool arch_vmap_pud_supported(pgprot_t prot);
+bool arch_vmap_pmd_supported(pgprot_t prot);
+#endif
+
 #endif /* _ASM_X86_VMALLOC_H */
diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c
index 9e5ccc56f8e0..fbaf0c447986 100644
--- a/arch/x86/mm/ioremap.c
+++ b/arch/x86/mm/ioremap.c
@@ -481,24 +481,26 @@ void iounmap(volatile void __iomem *addr)
 }
 EXPORT_SYMBOL(iounmap);
 
-int __init arch_ioremap_p4d_supported(void)
+#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
+bool arch_vmap_p4d_supported(pgprot_t prot)
 {
-	return 0;
+	return false;
 }
 
-int __init arch_ioremap_pud_supported(void)
+bool arch_vmap_pud_supported(pgprot_t prot)
 {
 #ifdef CONFIG_X86_64
 	return boot_cpu_has(X86_FEATURE_GBPAGES);
 #else
-	return 0;
+	return false;
 #endif
 }
 
-int __init arch_ioremap_pmd_supported(void)
+bool arch_vmap_pmd_supported(pgprot_t prot)
 {
 	return boot_cpu_has(X86_FEATURE_PSE);
 }
+#endif
 
 /*
  * Convert a physical pointer to a virtual kernel pointer for /dev/mem
diff --git a/include/linux/io.h b/include/linux/io.h
index 8394c56babc2..f1effd4d7a3c 100644
--- a/include/linux/io.h
+++ b/include/linux/io.h
@@ -31,15 +31,6 @@ static inline int ioremap_page_range(unsigned long addr, unsigned long end,
 }
 #endif
 
-#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
-void __init ioremap_huge_init(void);
-int arch_ioremap_p4d_supported(void);
-int arch_ioremap_pud_supported(void);
-int arch_ioremap_pmd_supported(void);
-#else
-static inline void ioremap_huge_init(void) { }
-#endif
-
 /*
  * Managed iomap interface
  */
diff --git a/include/linux/vmalloc.h b/include/linux/vmalloc.h
index 80c0181c411d..00bd62bd701e 100644
--- a/include/linux/vmalloc.h
+++ b/include/linux/vmalloc.h
@@ -83,6 +83,12 @@ struct vmap_area {
 	};
 };
 
+#ifndef CONFIG_HAVE_ARCH_HUGE_VMAP
+static inline bool arch_vmap_p4d_supported(pgprot_t prot) { return false; }
+static inline bool arch_vmap_pud_supported(pgprot_t prot) { return false; }
+static inline bool arch_vmap_pmd_supported(pgprot_t prot) { return false; }
+#endif
+
 /*
  *	Highlevel APIs for driver use
  */
diff --git a/init/main.c b/init/main.c
index c68d784376ca..bf9389e5b2e4 100644
--- a/init/main.c
+++ b/init/main.c
@@ -834,7 +834,6 @@ static void __init mm_init(void)
 	pgtable_init();
 	debug_objects_mem_init();
 	vmalloc_init();
-	ioremap_huge_init();
 	/* Should be run before the first non-init thread is created */
 	init_espfix_bsp();
 	/* Should be run after espfix64 is set up. */
diff --git a/mm/ioremap.c b/mm/ioremap.c
index 3f4d36f9745a..3264d0203785 100644
--- a/mm/ioremap.c
+++ b/mm/ioremap.c
@@ -16,49 +16,16 @@
 #include "pgalloc-track.h"
 
 #ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
-static int __read_mostly ioremap_p4d_capable;
-static int __read_mostly ioremap_pud_capable;
-static int __read_mostly ioremap_pmd_capable;
-static int __read_mostly ioremap_huge_disabled;
+static bool __ro_after_init iomap_max_page_shift = PAGE_SHIFT;
 
 static int __init set_nohugeiomap(char *str)
 {
-	ioremap_huge_disabled = 1;
+	iomap_max_page_shift = P4D_SHIFT;
 	return 0;
 }
 early_param("nohugeiomap", set_nohugeiomap);
-
-void __init ioremap_huge_init(void)
-{
-	if (!ioremap_huge_disabled) {
-		if (arch_ioremap_p4d_supported())
-			ioremap_p4d_capable = 1;
-		if (arch_ioremap_pud_supported())
-			ioremap_pud_capable = 1;
-		if (arch_ioremap_pmd_supported())
-			ioremap_pmd_capable = 1;
-	}
-}
-
-static inline int ioremap_p4d_enabled(void)
-{
-	return ioremap_p4d_capable;
-}
-
-static inline int ioremap_pud_enabled(void)
-{
-	return ioremap_pud_capable;
-}
-
-static inline int ioremap_pmd_enabled(void)
-{
-	return ioremap_pmd_capable;
-}
-
-#else	/* !CONFIG_HAVE_ARCH_HUGE_VMAP */
-static inline int ioremap_p4d_enabled(void) { return 0; }
-static inline int ioremap_pud_enabled(void) { return 0; }
-static inline int ioremap_pmd_enabled(void) { return 0; }
+#else /* CONFIG_HAVE_ARCH_HUGE_VMAP */
+static const bool iomap_max_page_shift = PAGE_SHIFT;
 #endif	/* CONFIG_HAVE_ARCH_HUGE_VMAP */
 
 static int vmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
@@ -82,9 +49,13 @@ static int vmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
 }
 
 static int vmap_try_huge_pmd(pmd_t *pmd, unsigned long addr, unsigned long end,
-			phys_addr_t phys_addr, pgprot_t prot)
+			phys_addr_t phys_addr, pgprot_t prot,
+			unsigned int max_page_shift)
 {
-	if (!ioremap_pmd_enabled())
+	if (max_page_shift < PMD_SHIFT)
+		return 0;
+
+	if (!arch_vmap_pmd_supported(prot))
 		return 0;
 
 	if ((end - addr) != PMD_SIZE)
@@ -104,7 +75,7 @@ static int vmap_try_huge_pmd(pmd_t *pmd, unsigned long addr, unsigned long end,
 
 static int vmap_pmd_range(pud_t *pud, unsigned long addr, unsigned long end,
 			phys_addr_t phys_addr, pgprot_t prot,
-			pgtbl_mod_mask *mask)
+			unsigned int max_page_shift, pgtbl_mod_mask *mask)
 {
 	pmd_t *pmd;
 	unsigned long next;
@@ -115,7 +86,8 @@ static int vmap_pmd_range(pud_t *pud, unsigned long addr, unsigned long end,
 	do {
 		next = pmd_addr_end(addr, end);
 
-		if (vmap_try_huge_pmd(pmd, addr, next, phys_addr, prot)) {
+		if (vmap_try_huge_pmd(pmd, addr, next, phys_addr, prot,
+					max_page_shift)) {
 			*mask |= PGTBL_PMD_MODIFIED;
 			continue;
 		}
@@ -127,9 +99,13 @@ static int vmap_pmd_range(pud_t *pud, unsigned long addr, unsigned long end,
 }
 
 static int vmap_try_huge_pud(pud_t *pud, unsigned long addr, unsigned long end,
-			phys_addr_t phys_addr, pgprot_t prot)
+			phys_addr_t phys_addr, pgprot_t prot,
+			unsigned int max_page_shift)
 {
-	if (!ioremap_pud_enabled())
+	if (max_page_shift < PUD_SHIFT)
+		return 0;
+
+	if (!arch_vmap_pud_supported(prot))
 		return 0;
 
 	if ((end - addr) != PUD_SIZE)
@@ -149,7 +125,7 @@ static int vmap_try_huge_pud(pud_t *pud, unsigned long addr, unsigned long end,
 
 static int vmap_pud_range(p4d_t *p4d, unsigned long addr, unsigned long end,
 			phys_addr_t phys_addr, pgprot_t prot,
-			pgtbl_mod_mask *mask)
+			unsigned int max_page_shift, pgtbl_mod_mask *mask)
 {
 	pud_t *pud;
 	unsigned long next;
@@ -160,21 +136,27 @@ static int vmap_pud_range(p4d_t *p4d, unsigned long addr, unsigned long end,
 	do {
 		next = pud_addr_end(addr, end);
 
-		if (vmap_try_huge_pud(pud, addr, next, phys_addr, prot)) {
+		if (vmap_try_huge_pud(pud, addr, next, phys_addr, prot,
+					max_page_shift)) {
 			*mask |= PGTBL_PUD_MODIFIED;
 			continue;
 		}
 
-		if (vmap_pmd_range(pud, addr, next, phys_addr, prot, mask))
+		if (vmap_pmd_range(pud, addr, next, phys_addr, prot,
+					max_page_shift, mask))
 			return -ENOMEM;
 	} while (pud++, phys_addr += (next - addr), addr = next, addr != end);
 	return 0;
 }
 
 static int vmap_try_huge_p4d(p4d_t *p4d, unsigned long addr, unsigned long end,
-			phys_addr_t phys_addr, pgprot_t prot)
+			phys_addr_t phys_addr, pgprot_t prot,
+			unsigned int max_page_shift)
 {
-	if (!ioremap_p4d_enabled())
+	if (max_page_shift < P4D_SHIFT)
+		return 0;
+
+	if (!arch_vmap_p4d_supported(prot))
 		return 0;
 
 	if ((end - addr) != P4D_SIZE)
@@ -194,7 +176,7 @@ static int vmap_try_huge_p4d(p4d_t *p4d, unsigned long addr, unsigned long end,
 
 static int vmap_p4d_range(pgd_t *pgd, unsigned long addr, unsigned long end,
 			phys_addr_t phys_addr, pgprot_t prot,
-			pgtbl_mod_mask *mask)
+			unsigned int max_page_shift, pgtbl_mod_mask *mask)
 {
 	p4d_t *p4d;
 	unsigned long next;
@@ -205,19 +187,22 @@ static int vmap_p4d_range(pgd_t *pgd, unsigned long addr, unsigned long end,
 	do {
 		next = p4d_addr_end(addr, end);
 
-		if (vmap_try_huge_p4d(p4d, addr, next, phys_addr, prot)) {
+		if (vmap_try_huge_p4d(p4d, addr, next, phys_addr, prot,
+					max_page_shift)) {
 			*mask |= PGTBL_P4D_MODIFIED;
 			continue;
 		}
 
-		if (vmap_pud_range(p4d, addr, next, phys_addr, prot, mask))
+		if (vmap_pud_range(p4d, addr, next, phys_addr, prot,
+					max_page_shift, mask))
 			return -ENOMEM;
 	} while (p4d++, phys_addr += (next - addr), addr = next, addr != end);
 	return 0;
 }
 
 static int vmap_range(unsigned long addr, unsigned long end,
-			phys_addr_t phys_addr, pgprot_t prot)
+			phys_addr_t phys_addr, pgprot_t prot,
+			unsigned int max_page_shift)
 {
 	pgd_t *pgd;
 	unsigned long start;
@@ -232,7 +217,8 @@ static int vmap_range(unsigned long addr, unsigned long end,
 	pgd = pgd_offset_k(addr);
 	do {
 		next = pgd_addr_end(addr, end);
-		err = vmap_p4d_range(pgd, addr, next, phys_addr, prot, &mask);
+		err = vmap_p4d_range(pgd, addr, next, phys_addr, prot,
+					max_page_shift, &mask);
 		if (err)
 			break;
 	} while (pgd++, phys_addr += (next - addr), addr = next, addr != end);
@@ -248,7 +234,7 @@ static int vmap_range(unsigned long addr, unsigned long end,
 int ioremap_page_range(unsigned long addr,
 		       unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
 {
-	return vmap_range(addr, end, phys_addr, prot);
+	return vmap_range(addr, end, phys_addr, prot, iomap_max_page_shift);
 }
 
 #ifdef CONFIG_GENERIC_IOREMAP
-- 
2.23.0

[PATCH v11 06/13] powerpc: inline huge vmap supported functions

[Nicholas Piggin]

This allows unsupported levels to be constant folded away, and so
p4d_free_pud_page can be removed because it's no longer linked to.

Cc: linuxppc-dev@lists.ozlabs.org
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 arch/powerpc/include/asm/vmalloc.h       | 19 ++++++++++++++++---
 arch/powerpc/mm/book3s64/radix_pgtable.c | 21 ---------------------
 2 files changed, 16 insertions(+), 24 deletions(-)

diff --git a/arch/powerpc/include/asm/vmalloc.h b/arch/powerpc/include/asm/vmalloc.h
index 105abb73f075..3f0c153befb0 100644
--- a/arch/powerpc/include/asm/vmalloc.h
+++ b/arch/powerpc/include/asm/vmalloc.h
@@ -1,12 +1,25 @@
 #ifndef _ASM_POWERPC_VMALLOC_H
 #define _ASM_POWERPC_VMALLOC_H
 
+#include <asm/mmu.h>
 #include <asm/page.h>
 
 #ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
-bool arch_vmap_p4d_supported(pgprot_t prot);
-bool arch_vmap_pud_supported(pgprot_t prot);
-bool arch_vmap_pmd_supported(pgprot_t prot);
+static inline bool arch_vmap_p4d_supported(pgprot_t prot)
+{
+	return false;
+}
+
+static inline bool arch_vmap_pud_supported(pgprot_t prot)
+{
+	/* HPT does not cope with large pages in the vmalloc area */
+	return radix_enabled();
+}
+
+static inline bool arch_vmap_pmd_supported(pgprot_t prot)
+{
+	return radix_enabled();
+}
 #endif
 
 #endif /* _ASM_POWERPC_VMALLOC_H */
diff --git a/arch/powerpc/mm/book3s64/radix_pgtable.c b/arch/powerpc/mm/book3s64/radix_pgtable.c
index 743807fc210f..8da62afccee5 100644
--- a/arch/powerpc/mm/book3s64/radix_pgtable.c
+++ b/arch/powerpc/mm/book3s64/radix_pgtable.c
@@ -1082,22 +1082,6 @@ void radix__ptep_modify_prot_commit(struct vm_area_struct *vma,
 	set_pte_at(mm, addr, ptep, pte);
 }
 
-bool arch_vmap_pud_supported(pgprot_t prot)
-{
-	/* HPT does not cope with large pages in the vmalloc area */
-	return radix_enabled();
-}
-
-bool arch_vmap_pmd_supported(pgprot_t prot)
-{
-	return radix_enabled();
-}
-
-int p4d_free_pud_page(p4d_t *p4d, unsigned long addr)
-{
-	return 0;
-}
-
 int pud_set_huge(pud_t *pud, phys_addr_t addr, pgprot_t prot)
 {
 	pte_t *ptep = (pte_t *)pud;
@@ -1181,8 +1165,3 @@ int pmd_free_pte_page(pmd_t *pmd, unsigned long addr)
 
 	return 1;
 }
-
-bool arch_vmap_p4d_supported(pgprot_t prot)
-{
-	return false;
-}
-- 
2.23.0

[PATCH v11 07/13] arm64: inline huge vmap supported functions

[Nicholas Piggin]

This allows unsupported levels to be constant folded away, and so
p4d_free_pud_page can be removed because it's no longer linked to.

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: linux-arm-kernel@lists.infradead.org
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 arch/arm64/include/asm/vmalloc.h | 23 ++++++++++++++++++++---
 arch/arm64/mm/mmu.c              | 26 --------------------------
 2 files changed, 20 insertions(+), 29 deletions(-)

diff --git a/arch/arm64/include/asm/vmalloc.h b/arch/arm64/include/asm/vmalloc.h
index 597b40405319..fc9a12d6cc1a 100644
--- a/arch/arm64/include/asm/vmalloc.h
+++ b/arch/arm64/include/asm/vmalloc.h
@@ -4,9 +4,26 @@
 #include <asm/page.h>
 
 #ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
-bool arch_vmap_p4d_supported(pgprot_t prot);
-bool arch_vmap_pud_supported(pgprot_t prot);
-bool arch_vmap_pmd_supported(pgprot_t prot);
+static inline bool arch_vmap_p4d_supported(pgprot_t prot)
+{
+	return false;
+}
+
+static inline bool arch_vmap_pud_supported(pgprot_t prot)
+{
+	/*
+	 * Only 4k granule supports level 1 block mappings.
+	 * SW table walks can't handle removal of intermediate entries.
+	 */
+	return IS_ENABLED(CONFIG_ARM64_4K_PAGES) &&
+	       !IS_ENABLED(CONFIG_PTDUMP_DEBUGFS);
+}
+
+static inline bool arch_vmap_pmd_supported(pgprot_t prot)
+{
+	/* See arch_vmap_pud_supported() */
+	return !IS_ENABLED(CONFIG_PTDUMP_DEBUGFS);
+}
 #endif
 
 #endif /* _ASM_ARM64_VMALLOC_H */
diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
index 1613d290cbd1..ab9ba7c36dae 100644
--- a/arch/arm64/mm/mmu.c
+++ b/arch/arm64/mm/mmu.c
@@ -1313,27 +1313,6 @@ void *__init fixmap_remap_fdt(phys_addr_t dt_phys, int *size, pgprot_t prot)
 	return dt_virt;
 }
 
-bool arch_vmap_p4d_supported(pgprot_t prot)
-{
-	return false;
-}
-
-bool arch_vmap_pud_supported(pgprot_t prot)
-{
-	/*
-	 * Only 4k granule supports level 1 block mappings.
-	 * SW table walks can't handle removal of intermediate entries.
-	 */
-	return IS_ENABLED(CONFIG_ARM64_4K_PAGES) &&
-	       !IS_ENABLED(CONFIG_PTDUMP_DEBUGFS);
-}
-
-bool arch_vmap_pmd_supported(pgprot_t prot)
-{
-	/* See arch_vmap_pud_supported() */
-	return !IS_ENABLED(CONFIG_PTDUMP_DEBUGFS);
-}
-
 int pud_set_huge(pud_t *pudp, phys_addr_t phys, pgprot_t prot)
 {
 	pud_t new_pud = pfn_pud(__phys_to_pfn(phys), mk_pud_sect_prot(prot));
@@ -1425,11 +1404,6 @@ int pud_free_pmd_page(pud_t *pudp, unsigned long addr)
 	return 1;
 }
 
-int p4d_free_pud_page(p4d_t *p4d, unsigned long addr)
-{
-	return 0;	/* Don't attempt a block mapping */
-}
-
 #ifdef CONFIG_MEMORY_HOTPLUG
 static void __remove_pgd_mapping(pgd_t *pgdir, unsigned long start, u64 size)
 {
-- 
2.23.0

[PATCH v11 08/13] x86: inline huge vmap supported functions

[Nicholas Piggin]

This allows unsupported levels to be constant folded away, and so
p4d_free_pud_page can be removed because it's no longer linked to.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: x86@kernel.org
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 arch/x86/include/asm/vmalloc.h | 22 +++++++++++++++++++---
 arch/x86/mm/ioremap.c          | 21 ---------------------
 arch/x86/mm/pgtable.c          | 13 -------------
 3 files changed, 19 insertions(+), 37 deletions(-)

diff --git a/arch/x86/include/asm/vmalloc.h b/arch/x86/include/asm/vmalloc.h
index 094ea2b565f3..e714b00fc0ca 100644
--- a/arch/x86/include/asm/vmalloc.h
+++ b/arch/x86/include/asm/vmalloc.h
@@ -1,13 +1,29 @@
 #ifndef _ASM_X86_VMALLOC_H
 #define _ASM_X86_VMALLOC_H
 
+#include <asm/cpufeature.h>
 #include <asm/page.h>
 #include <asm/pgtable_areas.h>
 
 #ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
-bool arch_vmap_p4d_supported(pgprot_t prot);
-bool arch_vmap_pud_supported(pgprot_t prot);
-bool arch_vmap_pmd_supported(pgprot_t prot);
+static inline bool arch_vmap_p4d_supported(pgprot_t prot)
+{
+	return false;
+}
+
+static inline bool arch_vmap_pud_supported(pgprot_t prot)
+{
+#ifdef CONFIG_X86_64
+	return boot_cpu_has(X86_FEATURE_GBPAGES);
+#else
+	return false;
+#endif
+}
+
+static inline bool arch_vmap_pmd_supported(pgprot_t prot)
+{
+	return boot_cpu_has(X86_FEATURE_PSE);
+}
 #endif
 
 #endif /* _ASM_X86_VMALLOC_H */
diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c
index fbaf0c447986..12c686c65ea9 100644
--- a/arch/x86/mm/ioremap.c
+++ b/arch/x86/mm/ioremap.c
@@ -481,27 +481,6 @@ void iounmap(volatile void __iomem *addr)
 }
 EXPORT_SYMBOL(iounmap);
 
-#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
-bool arch_vmap_p4d_supported(pgprot_t prot)
-{
-	return false;
-}
-
-bool arch_vmap_pud_supported(pgprot_t prot)
-{
-#ifdef CONFIG_X86_64
-	return boot_cpu_has(X86_FEATURE_GBPAGES);
-#else
-	return false;
-#endif
-}
-
-bool arch_vmap_pmd_supported(pgprot_t prot)
-{
-	return boot_cpu_has(X86_FEATURE_PSE);
-}
-#endif
-
 /*
  * Convert a physical pointer to a virtual kernel pointer for /dev/mem
  * access
diff --git a/arch/x86/mm/pgtable.c b/arch/x86/mm/pgtable.c
index f6a9e2e36642..d27cf69e811d 100644
--- a/arch/x86/mm/pgtable.c
+++ b/arch/x86/mm/pgtable.c
@@ -780,14 +780,6 @@ int pmd_clear_huge(pmd_t *pmd)
 	return 0;
 }
 
-/*
- * Until we support 512GB pages, skip them in the vmap area.
- */
-int p4d_free_pud_page(p4d_t *p4d, unsigned long addr)
-{
-	return 0;
-}
-
 #ifdef CONFIG_X86_64
 /**
  * pud_free_pmd_page - Clear pud entry and free pmd page.
@@ -861,11 +853,6 @@ int pmd_free_pte_page(pmd_t *pmd, unsigned long addr)
 
 #else /* !CONFIG_X86_64 */
 
-int pud_free_pmd_page(pud_t *pud, unsigned long addr)
-{
-	return pud_none(*pud);
-}
-
 /*
  * Disable free page handling on x86-PAE. This assures that ioremap()
  * does not update sync'd pmd entries. See vmalloc_sync_one().
-- 
2.23.0

[PATCH v11 09/13] mm/vmalloc: provide fallback arch huge vmap support functions

[Nicholas Piggin]

If an architecture doesn't support a particular page table level as
a huge vmap page size then allow it to skip defining the support
query function.

Suggested-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 arch/arm64/include/asm/vmalloc.h   |  7 +++----
 arch/powerpc/include/asm/vmalloc.h |  7 +++----
 arch/x86/include/asm/vmalloc.h     | 13 +++++--------
 include/linux/vmalloc.h            | 24 ++++++++++++++++++++----
 4 files changed, 31 insertions(+), 20 deletions(-)

diff --git a/arch/arm64/include/asm/vmalloc.h b/arch/arm64/include/asm/vmalloc.h
index fc9a12d6cc1a..7a22aeea9bb5 100644
--- a/arch/arm64/include/asm/vmalloc.h
+++ b/arch/arm64/include/asm/vmalloc.h
@@ -4,11 +4,8 @@
 #include <asm/page.h>
 
 #ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
-static inline bool arch_vmap_p4d_supported(pgprot_t prot)
-{
-	return false;
-}
 
+#define arch_vmap_pud_supported arch_vmap_pud_supported
 static inline bool arch_vmap_pud_supported(pgprot_t prot)
 {
 	/*
@@ -19,11 +16,13 @@ static inline bool arch_vmap_pud_supported(pgprot_t prot)
 	       !IS_ENABLED(CONFIG_PTDUMP_DEBUGFS);
 }
 
+#define arch_vmap_pmd_supported arch_vmap_pmd_supported
 static inline bool arch_vmap_pmd_supported(pgprot_t prot)
 {
 	/* See arch_vmap_pud_supported() */
 	return !IS_ENABLED(CONFIG_PTDUMP_DEBUGFS);
 }
+
 #endif
 
 #endif /* _ASM_ARM64_VMALLOC_H */
diff --git a/arch/powerpc/include/asm/vmalloc.h b/arch/powerpc/include/asm/vmalloc.h
index 3f0c153befb0..4c69ece52a31 100644
--- a/arch/powerpc/include/asm/vmalloc.h
+++ b/arch/powerpc/include/asm/vmalloc.h
@@ -5,21 +5,20 @@
 #include <asm/page.h>
 
 #ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
-static inline bool arch_vmap_p4d_supported(pgprot_t prot)
-{
-	return false;
-}
 
+#define arch_vmap_pud_supported arch_vmap_pud_supported
 static inline bool arch_vmap_pud_supported(pgprot_t prot)
 {
 	/* HPT does not cope with large pages in the vmalloc area */
 	return radix_enabled();
 }
 
+#define arch_vmap_pmd_supported arch_vmap_pmd_supported
 static inline bool arch_vmap_pmd_supported(pgprot_t prot)
 {
 	return radix_enabled();
 }
+
 #endif
 
 #endif /* _ASM_POWERPC_VMALLOC_H */
diff --git a/arch/x86/include/asm/vmalloc.h b/arch/x86/include/asm/vmalloc.h
index e714b00fc0ca..49ce331f3ac6 100644
--- a/arch/x86/include/asm/vmalloc.h
+++ b/arch/x86/include/asm/vmalloc.h
@@ -6,24 +6,21 @@
 #include <asm/pgtable_areas.h>
 
 #ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
-static inline bool arch_vmap_p4d_supported(pgprot_t prot)
-{
-	return false;
-}
 
+#ifdef CONFIG_X86_64
+#define arch_vmap_pud_supported arch_vmap_pud_supported
 static inline bool arch_vmap_pud_supported(pgprot_t prot)
 {
-#ifdef CONFIG_X86_64
 	return boot_cpu_has(X86_FEATURE_GBPAGES);
-#else
-	return false;
-#endif
 }
+#endif
 
+#define arch_vmap_pmd_supported arch_vmap_pmd_supported
 static inline bool arch_vmap_pmd_supported(pgprot_t prot)
 {
 	return boot_cpu_has(X86_FEATURE_PSE);
 }
+
 #endif
 
 #endif /* _ASM_X86_VMALLOC_H */
diff --git a/include/linux/vmalloc.h b/include/linux/vmalloc.h
index 00bd62bd701e..9f7b8b00101b 100644
--- a/include/linux/vmalloc.h
+++ b/include/linux/vmalloc.h
@@ -83,10 +83,26 @@ struct vmap_area {
 	};
 };
 
-#ifndef CONFIG_HAVE_ARCH_HUGE_VMAP
-static inline bool arch_vmap_p4d_supported(pgprot_t prot) { return false; }
-static inline bool arch_vmap_pud_supported(pgprot_t prot) { return false; }
-static inline bool arch_vmap_pmd_supported(pgprot_t prot) { return false; }
+/* archs that select HAVE_ARCH_HUGE_VMAP should override one or more of these */
+#ifndef arch_vmap_p4d_supported
+static inline bool arch_vmap_p4d_supported(pgprot_t prot)
+{
+	return false;
+}
+#endif
+
+#ifndef arch_vmap_pud_supported
+static inline bool arch_vmap_pud_supported(pgprot_t prot)
+{
+	return false;
+}
+#endif
+
+#ifndef arch_vmap_pmd_supported
+static inline bool arch_vmap_pmd_supported(pgprot_t prot)
+{
+	return false;
+}
 #endif
 
 /*
-- 
2.23.0

[PATCH v11 10/13] mm: Move vmap_range from mm/ioremap.c to mm/vmalloc.c

[Nicholas Piggin]

This is a generic kernel virtual memory mapper, not specific to ioremap.

Code is unchanged other than making vmap_range non-static.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 include/linux/vmalloc.h |   3 +
 mm/ioremap.c            | 203 ----------------------------------------
 mm/vmalloc.c            | 202 +++++++++++++++++++++++++++++++++++++++
 3 files changed, 205 insertions(+), 203 deletions(-)

diff --git a/include/linux/vmalloc.h b/include/linux/vmalloc.h
index 9f7b8b00101b..99ea72d547dc 100644
--- a/include/linux/vmalloc.h
+++ b/include/linux/vmalloc.h
@@ -194,6 +194,9 @@ extern struct vm_struct *remove_vm_area(const void *addr);
 extern struct vm_struct *find_vm_area(const void *addr);
 
 #ifdef CONFIG_MMU
+int vmap_range(unsigned long addr, unsigned long end,
+			phys_addr_t phys_addr, pgprot_t prot,
+			unsigned int max_page_shift);
 extern int map_kernel_range_noflush(unsigned long start, unsigned long size,
 				    pgprot_t prot, struct page **pages);
 int map_kernel_range(unsigned long start, unsigned long size, pgprot_t prot,
diff --git a/mm/ioremap.c b/mm/ioremap.c
index 3264d0203785..d1dcc7e744ac 100644
--- a/mm/ioremap.c
+++ b/mm/ioremap.c
@@ -28,209 +28,6 @@ early_param("nohugeiomap", set_nohugeiomap);
 static const bool iomap_max_page_shift = PAGE_SHIFT;
 #endif	/* CONFIG_HAVE_ARCH_HUGE_VMAP */
 
-static int vmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
-			phys_addr_t phys_addr, pgprot_t prot,
-			pgtbl_mod_mask *mask)
-{
-	pte_t *pte;
-	u64 pfn;
-
-	pfn = phys_addr >> PAGE_SHIFT;
-	pte = pte_alloc_kernel_track(pmd, addr, mask);
-	if (!pte)
-		return -ENOMEM;
-	do {
-		BUG_ON(!pte_none(*pte));
-		set_pte_at(&init_mm, addr, pte, pfn_pte(pfn, prot));
-		pfn++;
-	} while (pte++, addr += PAGE_SIZE, addr != end);
-	*mask |= PGTBL_PTE_MODIFIED;
-	return 0;
-}
-
-static int vmap_try_huge_pmd(pmd_t *pmd, unsigned long addr, unsigned long end,
-			phys_addr_t phys_addr, pgprot_t prot,
-			unsigned int max_page_shift)
-{
-	if (max_page_shift < PMD_SHIFT)
-		return 0;
-
-	if (!arch_vmap_pmd_supported(prot))
-		return 0;
-
-	if ((end - addr) != PMD_SIZE)
-		return 0;
-
-	if (!IS_ALIGNED(addr, PMD_SIZE))
-		return 0;
-
-	if (!IS_ALIGNED(phys_addr, PMD_SIZE))
-		return 0;
-
-	if (pmd_present(*pmd) && !pmd_free_pte_page(pmd, addr))
-		return 0;
-
-	return pmd_set_huge(pmd, phys_addr, prot);
-}
-
-static int vmap_pmd_range(pud_t *pud, unsigned long addr, unsigned long end,
-			phys_addr_t phys_addr, pgprot_t prot,
-			unsigned int max_page_shift, pgtbl_mod_mask *mask)
-{
-	pmd_t *pmd;
-	unsigned long next;
-
-	pmd = pmd_alloc_track(&init_mm, pud, addr, mask);
-	if (!pmd)
-		return -ENOMEM;
-	do {
-		next = pmd_addr_end(addr, end);
-
-		if (vmap_try_huge_pmd(pmd, addr, next, phys_addr, prot,
-					max_page_shift)) {
-			*mask |= PGTBL_PMD_MODIFIED;
-			continue;
-		}
-
-		if (vmap_pte_range(pmd, addr, next, phys_addr, prot, mask))
-			return -ENOMEM;
-	} while (pmd++, phys_addr += (next - addr), addr = next, addr != end);
-	return 0;
-}
-
-static int vmap_try_huge_pud(pud_t *pud, unsigned long addr, unsigned long end,
-			phys_addr_t phys_addr, pgprot_t prot,
-			unsigned int max_page_shift)
-{
-	if (max_page_shift < PUD_SHIFT)
-		return 0;
-
-	if (!arch_vmap_pud_supported(prot))
-		return 0;
-
-	if ((end - addr) != PUD_SIZE)
-		return 0;
-
-	if (!IS_ALIGNED(addr, PUD_SIZE))
-		return 0;
-
-	if (!IS_ALIGNED(phys_addr, PUD_SIZE))
-		return 0;
-
-	if (pud_present(*pud) && !pud_free_pmd_page(pud, addr))
-		return 0;
-
-	return pud_set_huge(pud, phys_addr, prot);
-}
-
-static int vmap_pud_range(p4d_t *p4d, unsigned long addr, unsigned long end,
-			phys_addr_t phys_addr, pgprot_t prot,
-			unsigned int max_page_shift, pgtbl_mod_mask *mask)
-{
-	pud_t *pud;
-	unsigned long next;
-
-	pud = pud_alloc_track(&init_mm, p4d, addr, mask);
-	if (!pud)
-		return -ENOMEM;
-	do {
-		next = pud_addr_end(addr, end);
-
-		if (vmap_try_huge_pud(pud, addr, next, phys_addr, prot,
-					max_page_shift)) {
-			*mask |= PGTBL_PUD_MODIFIED;
-			continue;
-		}
-
-		if (vmap_pmd_range(pud, addr, next, phys_addr, prot,
-					max_page_shift, mask))
-			return -ENOMEM;
-	} while (pud++, phys_addr += (next - addr), addr = next, addr != end);
-	return 0;
-}
-
-static int vmap_try_huge_p4d(p4d_t *p4d, unsigned long addr, unsigned long end,
-			phys_addr_t phys_addr, pgprot_t prot,
-			unsigned int max_page_shift)
-{
-	if (max_page_shift < P4D_SHIFT)
-		return 0;
-
-	if (!arch_vmap_p4d_supported(prot))
-		return 0;
-
-	if ((end - addr) != P4D_SIZE)
-		return 0;
-
-	if (!IS_ALIGNED(addr, P4D_SIZE))
-		return 0;
-
-	if (!IS_ALIGNED(phys_addr, P4D_SIZE))
-		return 0;
-
-	if (p4d_present(*p4d) && !p4d_free_pud_page(p4d, addr))
-		return 0;
-
-	return p4d_set_huge(p4d, phys_addr, prot);
-}
-
-static int vmap_p4d_range(pgd_t *pgd, unsigned long addr, unsigned long end,
-			phys_addr_t phys_addr, pgprot_t prot,
-			unsigned int max_page_shift, pgtbl_mod_mask *mask)
-{
-	p4d_t *p4d;
-	unsigned long next;
-
-	p4d = p4d_alloc_track(&init_mm, pgd, addr, mask);
-	if (!p4d)
-		return -ENOMEM;
-	do {
-		next = p4d_addr_end(addr, end);
-
-		if (vmap_try_huge_p4d(p4d, addr, next, phys_addr, prot,
-					max_page_shift)) {
-			*mask |= PGTBL_P4D_MODIFIED;
-			continue;
-		}
-
-		if (vmap_pud_range(p4d, addr, next, phys_addr, prot,
-					max_page_shift, mask))
-			return -ENOMEM;
-	} while (p4d++, phys_addr += (next - addr), addr = next, addr != end);
-	return 0;
-}
-
-static int vmap_range(unsigned long addr, unsigned long end,
-			phys_addr_t phys_addr, pgprot_t prot,
-			unsigned int max_page_shift)
-{
-	pgd_t *pgd;
-	unsigned long start;
-	unsigned long next;
-	int err;
-	pgtbl_mod_mask mask = 0;
-
-	might_sleep();
-	BUG_ON(addr >= end);
-
-	start = addr;
-	pgd = pgd_offset_k(addr);
-	do {
-		next = pgd_addr_end(addr, end);
-		err = vmap_p4d_range(pgd, addr, next, phys_addr, prot,
-					max_page_shift, &mask);
-		if (err)
-			break;
-	} while (pgd++, phys_addr += (next - addr), addr = next, addr != end);
-
-	flush_cache_vmap(start, end);
-
-	if (mask & ARCH_PAGE_TABLE_SYNC_MASK)
-		arch_sync_kernel_mappings(start, end);
-
-	return err;
-}
-
 int ioremap_page_range(unsigned long addr,
 		       unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
 {
diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index 7f2f36116980..f043386bb51d 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -68,6 +68,208 @@ static void free_work(struct work_struct *w)
 }
 
 /*** Page table manipulation functions ***/
+static int vmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
+			phys_addr_t phys_addr, pgprot_t prot,
+			pgtbl_mod_mask *mask)
+{
+	pte_t *pte;
+	u64 pfn;
+
+	pfn = phys_addr >> PAGE_SHIFT;
+	pte = pte_alloc_kernel_track(pmd, addr, mask);
+	if (!pte)
+		return -ENOMEM;
+	do {
+		BUG_ON(!pte_none(*pte));
+		set_pte_at(&init_mm, addr, pte, pfn_pte(pfn, prot));
+		pfn++;
+	} while (pte++, addr += PAGE_SIZE, addr != end);
+	*mask |= PGTBL_PTE_MODIFIED;
+	return 0;
+}
+
+static int vmap_try_huge_pmd(pmd_t *pmd, unsigned long addr, unsigned long end,
+			phys_addr_t phys_addr, pgprot_t prot,
+			unsigned int max_page_shift)
+{
+	if (max_page_shift < PMD_SHIFT)
+		return 0;
+
+	if (!arch_vmap_pmd_supported(prot))
+		return 0;
+
+	if ((end - addr) != PMD_SIZE)
+		return 0;
+
+	if (!IS_ALIGNED(addr, PMD_SIZE))
+		return 0;
+
+	if (!IS_ALIGNED(phys_addr, PMD_SIZE))
+		return 0;
+
+	if (pmd_present(*pmd) && !pmd_free_pte_page(pmd, addr))
+		return 0;
+
+	return pmd_set_huge(pmd, phys_addr, prot);
+}
+
+static int vmap_pmd_range(pud_t *pud, unsigned long addr, unsigned long end,
+			phys_addr_t phys_addr, pgprot_t prot,
+			unsigned int max_page_shift, pgtbl_mod_mask *mask)
+{
+	pmd_t *pmd;
+	unsigned long next;
+
+	pmd = pmd_alloc_track(&init_mm, pud, addr, mask);
+	if (!pmd)
+		return -ENOMEM;
+	do {
+		next = pmd_addr_end(addr, end);
+
+		if (vmap_try_huge_pmd(pmd, addr, next, phys_addr, prot,
+					max_page_shift)) {
+			*mask |= PGTBL_PMD_MODIFIED;
+			continue;
+		}
+
+		if (vmap_pte_range(pmd, addr, next, phys_addr, prot, mask))
+			return -ENOMEM;
+	} while (pmd++, phys_addr += (next - addr), addr = next, addr != end);
+	return 0;
+}
+
+static int vmap_try_huge_pud(pud_t *pud, unsigned long addr, unsigned long end,
+			phys_addr_t phys_addr, pgprot_t prot,
+			unsigned int max_page_shift)
+{
+	if (max_page_shift < PUD_SHIFT)
+		return 0;
+
+	if (!arch_vmap_pud_supported(prot))
+		return 0;
+
+	if ((end - addr) != PUD_SIZE)
+		return 0;
+
+	if (!IS_ALIGNED(addr, PUD_SIZE))
+		return 0;
+
+	if (!IS_ALIGNED(phys_addr, PUD_SIZE))
+		return 0;
+
+	if (pud_present(*pud) && !pud_free_pmd_page(pud, addr))
+		return 0;
+
+	return pud_set_huge(pud, phys_addr, prot);
+}
+
+static int vmap_pud_range(p4d_t *p4d, unsigned long addr, unsigned long end,
+			phys_addr_t phys_addr, pgprot_t prot,
+			unsigned int max_page_shift, pgtbl_mod_mask *mask)
+{
+	pud_t *pud;
+	unsigned long next;
+
+	pud = pud_alloc_track(&init_mm, p4d, addr, mask);
+	if (!pud)
+		return -ENOMEM;
+	do {
+		next = pud_addr_end(addr, end);
+
+		if (vmap_try_huge_pud(pud, addr, next, phys_addr, prot,
+					max_page_shift)) {
+			*mask |= PGTBL_PUD_MODIFIED;
+			continue;
+		}
+
+		if (vmap_pmd_range(pud, addr, next, phys_addr, prot,
+					max_page_shift, mask))
+			return -ENOMEM;
+	} while (pud++, phys_addr += (next - addr), addr = next, addr != end);
+	return 0;
+}
+
+static int vmap_try_huge_p4d(p4d_t *p4d, unsigned long addr, unsigned long end,
+			phys_addr_t phys_addr, pgprot_t prot,
+			unsigned int max_page_shift)
+{
+	if (max_page_shift < P4D_SHIFT)
+		return 0;
+
+	if (!arch_vmap_p4d_supported(prot))
+		return 0;
+
+	if ((end - addr) != P4D_SIZE)
+		return 0;
+
+	if (!IS_ALIGNED(addr, P4D_SIZE))
+		return 0;
+
+	if (!IS_ALIGNED(phys_addr, P4D_SIZE))
+		return 0;
+
+	if (p4d_present(*p4d) && !p4d_free_pud_page(p4d, addr))
+		return 0;
+
+	return p4d_set_huge(p4d, phys_addr, prot);
+}
+
+static int vmap_p4d_range(pgd_t *pgd, unsigned long addr, unsigned long end,
+			phys_addr_t phys_addr, pgprot_t prot,
+			unsigned int max_page_shift, pgtbl_mod_mask *mask)
+{
+	p4d_t *p4d;
+	unsigned long next;
+
+	p4d = p4d_alloc_track(&init_mm, pgd, addr, mask);
+	if (!p4d)
+		return -ENOMEM;
+	do {
+		next = p4d_addr_end(addr, end);
+
+		if (vmap_try_huge_p4d(p4d, addr, next, phys_addr, prot,
+					max_page_shift)) {
+			*mask |= PGTBL_P4D_MODIFIED;
+			continue;
+		}
+
+		if (vmap_pud_range(p4d, addr, next, phys_addr, prot,
+					max_page_shift, mask))
+			return -ENOMEM;
+	} while (p4d++, phys_addr += (next - addr), addr = next, addr != end);
+	return 0;
+}
+
+int vmap_range(unsigned long addr, unsigned long end,
+			phys_addr_t phys_addr, pgprot_t prot,
+			unsigned int max_page_shift)
+{
+	pgd_t *pgd;
+	unsigned long start;
+	unsigned long next;
+	int err;
+	pgtbl_mod_mask mask = 0;
+
+	might_sleep();
+	BUG_ON(addr >= end);
+
+	start = addr;
+	pgd = pgd_offset_k(addr);
+	do {
+		next = pgd_addr_end(addr, end);
+		err = vmap_p4d_range(pgd, addr, next, phys_addr, prot,
+					max_page_shift, &mask);
+		if (err)
+			break;
+	} while (pgd++, phys_addr += (next - addr), addr = next, addr != end);
+
+	flush_cache_vmap(start, end);
+
+	if (mask & ARCH_PAGE_TABLE_SYNC_MASK)
+		arch_sync_kernel_mappings(start, end);
+
+	return err;
+}
 
 static void vunmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
 			     pgtbl_mod_mask *mask)
-- 
2.23.0

[PATCH v11 11/13] mm/vmalloc: add vmap_range_noflush variant

[Nicholas Piggin]

As a side-effect, the order of flush_cache_vmap() and
arch_sync_kernel_mappings() calls are switched, but that now matches
the other callers in this file.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 mm/vmalloc.c | 16 +++++++++++++---
 1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index f043386bb51d..47ab4338cfff 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -240,7 +240,7 @@ static int vmap_p4d_range(pgd_t *pgd, unsigned long addr, unsigned long end,
 	return 0;
 }
 
-int vmap_range(unsigned long addr, unsigned long end,
+static int vmap_range_noflush(unsigned long addr, unsigned long end,
 			phys_addr_t phys_addr, pgprot_t prot,
 			unsigned int max_page_shift)
 {
@@ -263,14 +263,24 @@ int vmap_range(unsigned long addr, unsigned long end,
 			break;
 	} while (pgd++, phys_addr += (next - addr), addr = next, addr != end);
 
-	flush_cache_vmap(start, end);
-
 	if (mask & ARCH_PAGE_TABLE_SYNC_MASK)
 		arch_sync_kernel_mappings(start, end);
 
 	return err;
 }
 
+int vmap_range(unsigned long addr, unsigned long end,
+			phys_addr_t phys_addr, pgprot_t prot,
+			unsigned int max_page_shift)
+{
+	int err;
+
+	err = vmap_range_noflush(addr, end, phys_addr, prot, max_page_shift);
+	flush_cache_vmap(addr, end);
+
+	return err;
+}
+
 static void vunmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
 			     pgtbl_mod_mask *mask)
 {
-- 
2.23.0

[PATCH v11 12/13] mm/vmalloc: Hugepage vmalloc mappings

[Nicholas Piggin]

Support huge page vmalloc mappings. Config option HAVE_ARCH_HUGE_VMALLOC
enables support on architectures that define HAVE_ARCH_HUGE_VMAP and
supports PMD sized vmap mappings.

vmalloc will attempt to allocate PMD-sized pages if allocating PMD size
or larger, and fall back to small pages if that was unsuccessful.

Architectures must ensure that any arch specific vmalloc allocations
that require PAGE_SIZE mappings (e.g., module allocations vs strict
module rwx) use the VM_NOHUGE flag to inhibit larger mappings.

When hugepage vmalloc mappings are enabled in the next patch, this
reduces TLB misses by nearly 30x on a `git diff` workload on a 2-node
POWER9 (59,800 -> 2,100) and reduces CPU cycles by 0.54%.

This can result in more internal fragmentation and memory overhead for a
given allocation, an option nohugevmalloc is added to disable at boot.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 arch/Kconfig            |  11 ++
 include/linux/vmalloc.h |  21 ++++
 mm/page_alloc.c         |   5 +-
 mm/vmalloc.c            | 215 +++++++++++++++++++++++++++++++---------
 4 files changed, 205 insertions(+), 47 deletions(-)

diff --git a/arch/Kconfig b/arch/Kconfig
index 24862d15f3a3..eef170e0c9b8 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -724,6 +724,17 @@ config HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD
 config HAVE_ARCH_HUGE_VMAP
 	bool
 
+#
+#  Archs that select this would be capable of PMD-sized vmaps (i.e.,
+#  arch_vmap_pmd_supported() returns true), and they must make no assumptions
+#  that vmalloc memory is mapped with PAGE_SIZE ptes. The VM_NO_HUGE_VMAP flag
+#  can be used to prohibit arch-specific allocations from using hugepages to
+#  help with this (e.g., modules may require it).
+#
+config HAVE_ARCH_HUGE_VMALLOC
+	depends on HAVE_ARCH_HUGE_VMAP
+	bool
+
 config ARCH_WANT_HUGE_PMD_SHARE
 	bool
 
diff --git a/include/linux/vmalloc.h b/include/linux/vmalloc.h
index 99ea72d547dc..93270adf5db5 100644
--- a/include/linux/vmalloc.h
+++ b/include/linux/vmalloc.h
@@ -25,6 +25,7 @@ struct notifier_block;		/* in notifier.h */
 #define VM_NO_GUARD		0x00000040      /* don't add guard page */
 #define VM_KASAN		0x00000080      /* has allocated kasan shadow memory */
 #define VM_MAP_PUT_PAGES	0x00000100	/* put pages and free array in vfree */
+#define VM_NO_HUGE_VMAP		0x00000200	/* force PAGE_SIZE pte mapping */
 
 /*
  * VM_KASAN is used slighly differently depending on CONFIG_KASAN_VMALLOC.
@@ -59,6 +60,9 @@ struct vm_struct {
 	unsigned long		size;
 	unsigned long		flags;
 	struct page		**pages;
+#ifdef CONFIG_HAVE_ARCH_HUGE_VMALLOC
+	unsigned int		page_order;
+#endif
 	unsigned int		nr_pages;
 	phys_addr_t		phys_addr;
 	const void		*caller;
@@ -193,6 +197,22 @@ void free_vm_area(struct vm_struct *area);
 extern struct vm_struct *remove_vm_area(const void *addr);
 extern struct vm_struct *find_vm_area(const void *addr);
 
+static inline bool is_vm_area_hugepages(const void *addr)
+{
+	/*
+	 * This may not 100% tell if the area is mapped with > PAGE_SIZE
+	 * page table entries, if for some reason the architecture indicates
+	 * larger sizes are available but decides not to use them, nothing
+	 * prevents that. This only indicates the size of the physical page
+	 * allocated in the vmalloc layer.
+	 */
+#ifdef CONFIG_HAVE_ARCH_HUGE_VMALLOC
+	return find_vm_area(addr)->page_order > 0;
+#else
+	return false;
+#endif
+}
+
 #ifdef CONFIG_MMU
 int vmap_range(unsigned long addr, unsigned long end,
 			phys_addr_t phys_addr, pgprot_t prot,
@@ -210,6 +230,7 @@ static inline void set_vm_flush_reset_perms(void *addr)
 	if (vm)
 		vm->flags |= VM_FLUSH_RESET_PERMS;
 }
+
 #else
 static inline int
 map_kernel_range_noflush(unsigned long start, unsigned long size,
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 027f6481ba59..b7a9661fa232 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -72,6 +72,7 @@
 #include <linux/padata.h>
 #include <linux/khugepaged.h>
 #include <linux/buffer_head.h>
+#include <linux/vmalloc.h>
 
 #include <asm/sections.h>
 #include <asm/tlbflush.h>
@@ -8238,6 +8239,7 @@ void *__init alloc_large_system_hash(const char *tablename,
 	void *table = NULL;
 	gfp_t gfp_flags;
 	bool virt;
+	bool huge;
 
 	/* allow the kernel cmdline to have a say */
 	if (!numentries) {
@@ -8305,6 +8307,7 @@ void *__init alloc_large_system_hash(const char *tablename,
 		} else if (get_order(size) >= MAX_ORDER || hashdist) {
 			table = __vmalloc(size, gfp_flags);
 			virt = true;
+			huge = is_vm_area_hugepages(table);
 		} else {
 			/*
 			 * If bucketsize is not a power-of-two, we may free
@@ -8321,7 +8324,7 @@ void *__init alloc_large_system_hash(const char *tablename,
 
 	pr_info("%s hash table entries: %ld (order: %d, %lu bytes, %s)\n",
 		tablename, 1UL << log2qty, ilog2(size) - PAGE_SHIFT, size,
-		virt ? "vmalloc" : "linear");
+		virt ? (huge ? "vmalloc hugepage" : "vmalloc") : "linear");
 
 	if (_hash_shift)
 		*_hash_shift = log2qty;
diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index 47ab4338cfff..e9a28de04182 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -42,6 +42,19 @@
 #include "internal.h"
 #include "pgalloc-track.h"
 
+#ifdef CONFIG_HAVE_ARCH_HUGE_VMALLOC
+static bool __ro_after_init vmap_allow_huge = true;
+
+static int __init set_nohugevmalloc(char *str)
+{
+	vmap_allow_huge = false;
+	return 0;
+}
+early_param("nohugevmalloc", set_nohugevmalloc);
+#else /* CONFIG_HAVE_ARCH_HUGE_VMALLOC */
+static const bool vmap_allow_huge = false;
+#endif	/* CONFIG_HAVE_ARCH_HUGE_VMALLOC */
+
 bool is_vmalloc_addr(const void *x)
 {
 	unsigned long addr = (unsigned long)x;
@@ -483,31 +496,12 @@ static int vmap_pages_p4d_range(pgd_t *pgd, unsigned long addr,
 	return 0;
 }
 
-/**
- * map_kernel_range_noflush - map kernel VM area with the specified pages
- * @addr: start of the VM area to map
- * @size: size of the VM area to map
- * @prot: page protection flags to use
- * @pages: pages to map
- *
- * Map PFN_UP(@size) pages at @addr.  The VM area @addr and @size specify should
- * have been allocated using get_vm_area() and its friends.
- *
- * NOTE:
- * This function does NOT do any cache flushing.  The caller is responsible for
- * calling flush_cache_vmap() on to-be-mapped areas before calling this
- * function.
- *
- * RETURNS:
- * 0 on success, -errno on failure.
- */
-int map_kernel_range_noflush(unsigned long addr, unsigned long size,
-			     pgprot_t prot, struct page **pages)
+static int vmap_small_pages_range_noflush(unsigned long addr, unsigned long end,
+		pgprot_t prot, struct page **pages)
 {
 	unsigned long start = addr;
-	unsigned long end = addr + size;
-	unsigned long next;
 	pgd_t *pgd;
+	unsigned long next;
 	int err = 0;
 	int nr = 0;
 	pgtbl_mod_mask mask = 0;
@@ -529,6 +523,66 @@ int map_kernel_range_noflush(unsigned long addr, unsigned long size,
 	return 0;
 }
 
+static int vmap_pages_range_noflush(unsigned long addr, unsigned long end,
+		pgprot_t prot, struct page **pages, unsigned int page_shift)
+{
+	unsigned int i, nr = (end - addr) >> PAGE_SHIFT;
+
+	WARN_ON(page_shift < PAGE_SHIFT);
+
+	if (!IS_ENABLED(CONFIG_HAVE_ARCH_HUGE_VMALLOC) ||
+			page_shift == PAGE_SHIFT)
+		return vmap_small_pages_range_noflush(addr, end, prot, pages);
+
+	for (i = 0; i < nr; i += 1U << (page_shift - PAGE_SHIFT)) {
+		int err;
+
+		err = vmap_range_noflush(addr, addr + (1UL << page_shift),
+					__pa(page_address(pages[i])), prot,
+					page_shift);
+		if (err)
+			return err;
+
+		addr += 1UL << page_shift;
+	}
+
+	return 0;
+}
+
+static int vmap_pages_range(unsigned long addr, unsigned long end,
+		pgprot_t prot, struct page **pages, unsigned int page_shift)
+{
+	int err;
+
+	err = vmap_pages_range_noflush(addr, end, prot, pages, page_shift);
+	flush_cache_vmap(addr, end);
+	return err;
+}
+
+/**
+ * map_kernel_range_noflush - map kernel VM area with the specified pages
+ * @addr: start of the VM area to map
+ * @size: size of the VM area to map
+ * @prot: page protection flags to use
+ * @pages: pages to map
+ *
+ * Map PFN_UP(@size) pages at @addr.  The VM area @addr and @size specify should
+ * have been allocated using get_vm_area() and its friends.
+ *
+ * NOTE:
+ * This function does NOT do any cache flushing.  The caller is responsible for
+ * calling flush_cache_vmap() on to-be-mapped areas before calling this
+ * function.
+ *
+ * RETURNS:
+ * 0 on success, -errno on failure.
+ */
+int map_kernel_range_noflush(unsigned long addr, unsigned long size,
+			     pgprot_t prot, struct page **pages)
+{
+	return vmap_pages_range_noflush(addr, addr + size, prot, pages, PAGE_SHIFT);
+}
+
 int map_kernel_range(unsigned long start, unsigned long size, pgprot_t prot,
 		struct page **pages)
 {
@@ -2112,6 +2166,24 @@ EXPORT_SYMBOL(vm_map_ram);
 
 static struct vm_struct *vmlist __initdata;
 
+static inline unsigned int vm_area_page_order(struct vm_struct *vm)
+{
+#ifdef CONFIG_HAVE_ARCH_HUGE_VMALLOC
+	return vm->page_order;
+#else
+	return 0;
+#endif
+}
+
+static inline void set_vm_area_page_order(struct vm_struct *vm, unsigned int order)
+{
+#ifdef CONFIG_HAVE_ARCH_HUGE_VMALLOC
+	vm->page_order = order;
+#else
+	BUG_ON(order != 0);
+#endif
+}
+
 /**
  * vm_area_add_early - add vmap area early during boot
  * @vm: vm_struct to add
@@ -2422,6 +2494,7 @@ static inline void set_area_direct_map(const struct vm_struct *area,
 {
 	int i;
 
+	/* HUGE_VMALLOC passes small pages to set_direct_map */
 	for (i = 0; i < area->nr_pages; i++)
 		if (page_address(area->pages[i]))
 			set_direct_map(area->pages[i]);
@@ -2431,6 +2504,7 @@ static inline void set_area_direct_map(const struct vm_struct *area,
 static void vm_remove_mappings(struct vm_struct *area, int deallocate_pages)
 {
 	unsigned long start = ULONG_MAX, end = 0;
+	unsigned int page_order = vm_area_page_order(area);
 	int flush_reset = area->flags & VM_FLUSH_RESET_PERMS;
 	int flush_dmap = 0;
 	int i;
@@ -2455,11 +2529,14 @@ static void vm_remove_mappings(struct vm_struct *area, int deallocate_pages)
 	 * map. Find the start and end range of the direct mappings to make sure
 	 * the vm_unmap_aliases() flush includes the direct map.
 	 */
-	for (i = 0; i < area->nr_pages; i++) {
+	for (i = 0; i < area->nr_pages; i += 1U << page_order) {
 		unsigned long addr = (unsigned long)page_address(area->pages[i]);
 		if (addr) {
+			unsigned long page_size;
+
+			page_size = PAGE_SIZE << page_order;
 			start = min(addr, start);
-			end = max(addr + PAGE_SIZE, end);
+			end = max(addr + page_size, end);
 			flush_dmap = 1;
 		}
 	}
@@ -2500,13 +2577,14 @@ static void __vunmap(const void *addr, int deallocate_pages)
 	vm_remove_mappings(area, deallocate_pages);
 
 	if (deallocate_pages) {
+		unsigned int page_order = vm_area_page_order(area);
 		int i;
 
-		for (i = 0; i < area->nr_pages; i++) {
+		for (i = 0; i < area->nr_pages; i += 1U << page_order) {
 			struct page *page = area->pages[i];
 
 			BUG_ON(!page);
-			__free_pages(page, 0);
+			__free_pages(page, page_order);
 		}
 		atomic_long_sub(area->nr_pages, &nr_vmalloc_pages);
 
@@ -2697,15 +2775,19 @@ EXPORT_SYMBOL_GPL(vmap_pfn);
 #endif /* CONFIG_VMAP_PFN */
 
 static void *__vmalloc_area_node(struct vm_struct *area, gfp_t gfp_mask,
-				 pgprot_t prot, int node)
+				 pgprot_t prot, unsigned int page_shift,
+				 int node)
 {
 	const gfp_t nested_gfp = (gfp_mask & GFP_RECLAIM_MASK) | __GFP_ZERO;
-	unsigned int nr_pages = get_vm_area_size(area) >> PAGE_SHIFT;
+	unsigned long addr = (unsigned long)area->addr;
+	unsigned long size = get_vm_area_size(area);
 	unsigned long array_size;
-	unsigned int i;
+	unsigned int nr_small_pages = size >> PAGE_SHIFT;
+	unsigned int page_order;
 	struct page **pages;
+	unsigned int i;
 
-	array_size = (unsigned long)nr_pages * sizeof(struct page *);
+	array_size = (unsigned long)nr_small_pages * sizeof(struct page *);
 	gfp_mask |= __GFP_NOWARN;
 	if (!(gfp_mask & (GFP_DMA | GFP_DMA32)))
 		gfp_mask |= __GFP_HIGHMEM;
@@ -2724,30 +2806,37 @@ static void *__vmalloc_area_node(struct vm_struct *area, gfp_t gfp_mask,
 	}
 
 	area->pages = pages;
-	area->nr_pages = nr_pages;
+	area->nr_pages = nr_small_pages;
+	set_vm_area_page_order(area, page_shift - PAGE_SHIFT);
 
-	for (i = 0; i < area->nr_pages; i++) {
-		struct page *page;
+	page_order = vm_area_page_order(area);
 
-		if (node == NUMA_NO_NODE)
-			page = alloc_page(gfp_mask);
-		else
-			page = alloc_pages_node(node, gfp_mask, 0);
+	/*
+	 * Careful, we allocate and map page_order pages, but tracking is done
+	 * per PAGE_SIZE page so as to keep the vm_struct APIs independent of
+	 * the physical/mapped size.
+	 */
+	for (i = 0; i < area->nr_pages; i += 1U << page_order) {
+		struct page *page;
+		int p;
 
+		page = alloc_pages_node(node, gfp_mask, page_order);
 		if (unlikely(!page)) {
 			/* Successfully allocated i pages, free them in __vfree() */
 			area->nr_pages = i;
 			atomic_long_add(area->nr_pages, &nr_vmalloc_pages);
 			goto fail;
 		}
-		area->pages[i] = page;
+
+		for (p = 0; p < (1U << page_order); p++)
+			area->pages[i + p] = page + p;
+
 		if (gfpflags_allow_blocking(gfp_mask))
 			cond_resched();
 	}
 	atomic_long_add(area->nr_pages, &nr_vmalloc_pages);
 
-	if (map_kernel_range((unsigned long)area->addr, get_vm_area_size(area),
-			prot, pages) < 0)
+	if (vmap_pages_range(addr, addr + size, prot, pages, page_shift) < 0)
 		goto fail;
 
 	return area->addr;
@@ -2755,7 +2844,7 @@ static void *__vmalloc_area_node(struct vm_struct *area, gfp_t gfp_mask,
 fail:
 	warn_alloc(gfp_mask, NULL,
 			  "vmalloc: allocation failure, allocated %ld of %ld bytes",
-			  (area->nr_pages*PAGE_SIZE), area->size);
+			  (area->nr_pages*PAGE_SIZE), size);
 	__vfree(area->addr);
 	return NULL;
 }
@@ -2786,19 +2875,43 @@ void *__vmalloc_node_range(unsigned long size, unsigned long align,
 	struct vm_struct *area;
 	void *addr;
 	unsigned long real_size = size;
+	unsigned long real_align = align;
+	unsigned int shift = PAGE_SHIFT;
 
-	size = PAGE_ALIGN(size);
 	if (!size || (size >> PAGE_SHIFT) > totalram_pages())
 		goto fail;
 
-	area = __get_vm_area_node(real_size, align, VM_ALLOC | VM_UNINITIALIZED |
+	if (vmap_allow_huge && !(vm_flags & VM_NO_HUGE_VMAP) &&
+			arch_vmap_pmd_supported(prot)) {
+		unsigned long size_per_node;
+
+		/*
+		 * Try huge pages. Only try for PAGE_KERNEL allocations,
+		 * others like modules don't yet expect huge pages in
+		 * their allocations due to apply_to_page_range not
+		 * supporting them.
+		 */
+
+		size_per_node = size;
+		if (node == NUMA_NO_NODE)
+			size_per_node /= num_online_nodes();
+		if (size_per_node >= PMD_SIZE) {
+			shift = PMD_SHIFT;
+			align = max(real_align, 1UL << shift);
+			size = ALIGN(real_size, 1UL << shift);
+		}
+	}
+
+again:
+	size = PAGE_ALIGN(size);
+	area = __get_vm_area_node(size, align, VM_ALLOC | VM_UNINITIALIZED |
 				vm_flags, start, end, node, gfp_mask, caller);
 	if (!area)
 		goto fail;
 
-	addr = __vmalloc_area_node(area, gfp_mask, prot, node);
+	addr = __vmalloc_area_node(area, gfp_mask, prot, shift, node);
 	if (!addr)
-		return NULL;
+		goto fail;
 
 	/*
 	 * In this function, newly allocated vm_struct has VM_UNINITIALIZED
@@ -2812,8 +2925,18 @@ void *__vmalloc_node_range(unsigned long size, unsigned long align,
 	return addr;
 
 fail:
-	warn_alloc(gfp_mask, NULL,
+	if (shift > PAGE_SHIFT) {
+		shift = PAGE_SHIFT;
+		align = real_align;
+		size = real_size;
+		goto again;
+	}
+
+	if (!area) {
+		/* Warn for area allocation, page allocations already warn */
+		warn_alloc(gfp_mask, NULL,
 			  "vmalloc: allocation failure: %lu bytes", real_size);
+	}
 	return NULL;
 }
 
-- 
2.23.0

[PATCH v11 13/13] powerpc/64s/radix: Enable huge vmalloc mappings

[Nicholas Piggin]

Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 .../admin-guide/kernel-parameters.txt         |  2 ++
 arch/powerpc/Kconfig                          |  1 +
 arch/powerpc/kernel/module.c                  | 21 +++++++++++++++----
 3 files changed, 20 insertions(+), 4 deletions(-)

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index a10b545c2070..d62df53e5200 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -3225,6 +3225,8 @@
 
 	nohugeiomap	[KNL,X86,PPC,ARM64] Disable kernel huge I/O mappings.
 
+	nohugevmalloc	[PPC] Disable kernel huge vmalloc mappings.
+
 	nosmt		[KNL,S390] Disable symmetric multithreading (SMT).
 			Equivalent to smt=1.
 
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 107bb4319e0e..781da6829ab7 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -181,6 +181,7 @@ config PPC
 	select GENERIC_GETTIMEOFDAY
 	select HAVE_ARCH_AUDITSYSCALL
 	select HAVE_ARCH_HUGE_VMAP		if PPC_BOOK3S_64 && PPC_RADIX_MMU
+	select HAVE_ARCH_HUGE_VMALLOC		if HAVE_ARCH_HUGE_VMAP
 	select HAVE_ARCH_JUMP_LABEL
 	select HAVE_ARCH_KASAN			if PPC32 && PPC_PAGE_SHIFT <= 14
 	select HAVE_ARCH_KASAN_VMALLOC		if PPC32 && PPC_PAGE_SHIFT <= 14
diff --git a/arch/powerpc/kernel/module.c b/arch/powerpc/kernel/module.c
index a211b0253cdb..07026335d24d 100644
--- a/arch/powerpc/kernel/module.c
+++ b/arch/powerpc/kernel/module.c
@@ -87,13 +87,26 @@ int module_finalize(const Elf_Ehdr *hdr,
 	return 0;
 }
 
-#ifdef MODULES_VADDR
 void *module_alloc(unsigned long size)
 {
+	unsigned long start = VMALLOC_START;
+	unsigned long end = VMALLOC_END;
+
+#ifdef MODULES_VADDR
 	BUILD_BUG_ON(TASK_SIZE > MODULES_VADDR);
+	start = MODULES_VADDR;
+	end = MODULES_END;
+#endif
+
+	/*
+	 * Don't do huge page allocations for modules yet until more testing
+	 * is done. STRICT_MODULE_RWX may require extra work to support this
+	 * too.
+	 */
 
-	return __vmalloc_node_range(size, 1, MODULES_VADDR, MODULES_END, GFP_KERNEL,
-				    PAGE_KERNEL_EXEC, VM_FLUSH_RESET_PERMS, NUMA_NO_NODE,
+	return __vmalloc_node_range(size, 1, start, end, GFP_KERNEL,
+				    PAGE_KERNEL_EXEC,
+				    VM_NO_HUGE_VMAP | VM_FLUSH_RESET_PERMS,
+				    NUMA_NO_NODE,
 				    __builtin_return_address(0));
 }
-#endif
-- 
2.23.0

Re: [PATCH v11 05/13] mm: HUGE_VMAP arch support cleanup

[Ding Tianhong]

Reviewed-by: Ding Tianhong <dingtianhong@huawei.com>

On 2021/1/26 12:45, Nicholas Piggin wrote:
> This changes the awkward approach where architectures provide init
> functions to determine which levels they can provide large mappings for,
> to one where the arch is queried for each call.
> 
> This removes code and indirection, and allows constant-folding of dead
> code for unsupported levels.
> 
> This also adds a prot argument to the arch query. This is unused
> currently but could help with some architectures (e.g., some powerpc
> processors can't map uncacheable memory with large pages).
> 
> Cc: linuxppc-dev@lists.ozlabs.org
> Cc: Catalin Marinas <catalin.marinas@arm.com>
> Cc: Will Deacon <will@kernel.org>
> Cc: linux-arm-kernel@lists.infradead.org
> Cc: Thomas Gleixner <tglx@linutronix.de>
> Cc: Ingo Molnar <mingo@redhat.com>
> Cc: Borislav Petkov <bp@alien8.de>
> Cc: x86@kernel.org
> Cc: "H. Peter Anvin" <hpa@zytor.com>
> Acked-by: Catalin Marinas <catalin.marinas@arm.com> [arm64]
> Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
> ---
>  arch/arm64/include/asm/vmalloc.h         |  8 ++
>  arch/arm64/mm/mmu.c                      | 10 +--
>  arch/powerpc/include/asm/vmalloc.h       |  8 ++
>  arch/powerpc/mm/book3s64/radix_pgtable.c |  8 +-
>  arch/x86/include/asm/vmalloc.h           |  7 ++
>  arch/x86/mm/ioremap.c                    | 12 +--
>  include/linux/io.h                       |  9 ---
>  include/linux/vmalloc.h                  |  6 ++
>  init/main.c                              |  1 -
>  mm/ioremap.c                             | 94 ++++++++++--------------
>  10 files changed, 85 insertions(+), 78 deletions(-)
> 
> diff --git a/arch/arm64/include/asm/vmalloc.h b/arch/arm64/include/asm/vmalloc.h
> index 2ca708ab9b20..597b40405319 100644
> --- a/arch/arm64/include/asm/vmalloc.h
> +++ b/arch/arm64/include/asm/vmalloc.h
> @@ -1,4 +1,12 @@
>  #ifndef _ASM_ARM64_VMALLOC_H
>  #define _ASM_ARM64_VMALLOC_H
>  
> +#include <asm/page.h>
> +
> +#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
> +bool arch_vmap_p4d_supported(pgprot_t prot);
> +bool arch_vmap_pud_supported(pgprot_t prot);
> +bool arch_vmap_pmd_supported(pgprot_t prot);
> +#endif
> +
>  #endif /* _ASM_ARM64_VMALLOC_H */
> diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
> index ae0c3d023824..1613d290cbd1 100644
> --- a/arch/arm64/mm/mmu.c
> +++ b/arch/arm64/mm/mmu.c
> @@ -1313,12 +1313,12 @@ void *__init fixmap_remap_fdt(phys_addr_t dt_phys, int *size, pgprot_t prot)
>  	return dt_virt;
>  }
>  
> -int __init arch_ioremap_p4d_supported(void)
> +bool arch_vmap_p4d_supported(pgprot_t prot)
>  {
> -	return 0;
> +	return false;
>  }
>  
> -int __init arch_ioremap_pud_supported(void)
> +bool arch_vmap_pud_supported(pgprot_t prot)
>  {
>  	/*
>  	 * Only 4k granule supports level 1 block mappings.
> @@ -1328,9 +1328,9 @@ int __init arch_ioremap_pud_supported(void)
>  	       !IS_ENABLED(CONFIG_PTDUMP_DEBUGFS);
>  }
>  
> -int __init arch_ioremap_pmd_supported(void)
> +bool arch_vmap_pmd_supported(pgprot_t prot)
>  {
> -	/* See arch_ioremap_pud_supported() */
> +	/* See arch_vmap_pud_supported() */
>  	return !IS_ENABLED(CONFIG_PTDUMP_DEBUGFS);
>  }
>  
> diff --git a/arch/powerpc/include/asm/vmalloc.h b/arch/powerpc/include/asm/vmalloc.h
> index b992dfaaa161..105abb73f075 100644
> --- a/arch/powerpc/include/asm/vmalloc.h
> +++ b/arch/powerpc/include/asm/vmalloc.h
> @@ -1,4 +1,12 @@
>  #ifndef _ASM_POWERPC_VMALLOC_H
>  #define _ASM_POWERPC_VMALLOC_H
>  
> +#include <asm/page.h>
> +
> +#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
> +bool arch_vmap_p4d_supported(pgprot_t prot);
> +bool arch_vmap_pud_supported(pgprot_t prot);
> +bool arch_vmap_pmd_supported(pgprot_t prot);
> +#endif
> +
>  #endif /* _ASM_POWERPC_VMALLOC_H */
> diff --git a/arch/powerpc/mm/book3s64/radix_pgtable.c b/arch/powerpc/mm/book3s64/radix_pgtable.c
> index 98f0b243c1ab..743807fc210f 100644
> --- a/arch/powerpc/mm/book3s64/radix_pgtable.c
> +++ b/arch/powerpc/mm/book3s64/radix_pgtable.c
> @@ -1082,13 +1082,13 @@ void radix__ptep_modify_prot_commit(struct vm_area_struct *vma,
>  	set_pte_at(mm, addr, ptep, pte);
>  }
>  
> -int __init arch_ioremap_pud_supported(void)
> +bool arch_vmap_pud_supported(pgprot_t prot)
>  {
>  	/* HPT does not cope with large pages in the vmalloc area */
>  	return radix_enabled();
>  }
>  
> -int __init arch_ioremap_pmd_supported(void)
> +bool arch_vmap_pmd_supported(pgprot_t prot)
>  {
>  	return radix_enabled();
>  }
> @@ -1182,7 +1182,7 @@ int pmd_free_pte_page(pmd_t *pmd, unsigned long addr)
>  	return 1;
>  }
>  
> -int __init arch_ioremap_p4d_supported(void)
> +bool arch_vmap_p4d_supported(pgprot_t prot)
>  {
> -	return 0;
> +	return false;
>  }
> diff --git a/arch/x86/include/asm/vmalloc.h b/arch/x86/include/asm/vmalloc.h
> index 29837740b520..094ea2b565f3 100644
> --- a/arch/x86/include/asm/vmalloc.h
> +++ b/arch/x86/include/asm/vmalloc.h
> @@ -1,6 +1,13 @@
>  #ifndef _ASM_X86_VMALLOC_H
>  #define _ASM_X86_VMALLOC_H
>  
> +#include <asm/page.h>
>  #include <asm/pgtable_areas.h>
>  
> +#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
> +bool arch_vmap_p4d_supported(pgprot_t prot);
> +bool arch_vmap_pud_supported(pgprot_t prot);
> +bool arch_vmap_pmd_supported(pgprot_t prot);
> +#endif
> +
>  #endif /* _ASM_X86_VMALLOC_H */
> diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c
> index 9e5ccc56f8e0..fbaf0c447986 100644
> --- a/arch/x86/mm/ioremap.c
> +++ b/arch/x86/mm/ioremap.c
> @@ -481,24 +481,26 @@ void iounmap(volatile void __iomem *addr)
>  }
>  EXPORT_SYMBOL(iounmap);
>  
> -int __init arch_ioremap_p4d_supported(void)
> +#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
> +bool arch_vmap_p4d_supported(pgprot_t prot)
>  {
> -	return 0;
> +	return false;
>  }
>  
> -int __init arch_ioremap_pud_supported(void)
> +bool arch_vmap_pud_supported(pgprot_t prot)
>  {
>  #ifdef CONFIG_X86_64
>  	return boot_cpu_has(X86_FEATURE_GBPAGES);
>  #else
> -	return 0;
> +	return false;
>  #endif
>  }
>  
> -int __init arch_ioremap_pmd_supported(void)
> +bool arch_vmap_pmd_supported(pgprot_t prot)
>  {
>  	return boot_cpu_has(X86_FEATURE_PSE);
>  }
> +#endif
>  
>  /*
>   * Convert a physical pointer to a virtual kernel pointer for /dev/mem
> diff --git a/include/linux/io.h b/include/linux/io.h
> index 8394c56babc2..f1effd4d7a3c 100644
> --- a/include/linux/io.h
> +++ b/include/linux/io.h
> @@ -31,15 +31,6 @@ static inline int ioremap_page_range(unsigned long addr, unsigned long end,
>  }
>  #endif
>  
> -#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
> -void __init ioremap_huge_init(void);
> -int arch_ioremap_p4d_supported(void);
> -int arch_ioremap_pud_supported(void);
> -int arch_ioremap_pmd_supported(void);
> -#else
> -static inline void ioremap_huge_init(void) { }
> -#endif
> -
>  /*
>   * Managed iomap interface
>   */
> diff --git a/include/linux/vmalloc.h b/include/linux/vmalloc.h
> index 80c0181c411d..00bd62bd701e 100644
> --- a/include/linux/vmalloc.h
> +++ b/include/linux/vmalloc.h
> @@ -83,6 +83,12 @@ struct vmap_area {
>  	};
>  };
>  
> +#ifndef CONFIG_HAVE_ARCH_HUGE_VMAP
> +static inline bool arch_vmap_p4d_supported(pgprot_t prot) { return false; }
> +static inline bool arch_vmap_pud_supported(pgprot_t prot) { return false; }
> +static inline bool arch_vmap_pmd_supported(pgprot_t prot) { return false; }
> +#endif
> +
>  /*
>   *	Highlevel APIs for driver use
>   */
> diff --git a/init/main.c b/init/main.c
> index c68d784376ca..bf9389e5b2e4 100644
> --- a/init/main.c
> +++ b/init/main.c
> @@ -834,7 +834,6 @@ static void __init mm_init(void)
>  	pgtable_init();
>  	debug_objects_mem_init();
>  	vmalloc_init();
> -	ioremap_huge_init();
>  	/* Should be run before the first non-init thread is created */
>  	init_espfix_bsp();
>  	/* Should be run after espfix64 is set up. */
> diff --git a/mm/ioremap.c b/mm/ioremap.c
> index 3f4d36f9745a..3264d0203785 100644
> --- a/mm/ioremap.c
> +++ b/mm/ioremap.c
> @@ -16,49 +16,16 @@
>  #include "pgalloc-track.h"
>  
>  #ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
> -static int __read_mostly ioremap_p4d_capable;
> -static int __read_mostly ioremap_pud_capable;
> -static int __read_mostly ioremap_pmd_capable;
> -static int __read_mostly ioremap_huge_disabled;
> +static bool __ro_after_init iomap_max_page_shift = PAGE_SHIFT;
>  
>  static int __init set_nohugeiomap(char *str)
>  {
> -	ioremap_huge_disabled = 1;
> +	iomap_max_page_shift = P4D_SHIFT;
>  	return 0;
>  }
>  early_param("nohugeiomap", set_nohugeiomap);
> -
> -void __init ioremap_huge_init(void)
> -{
> -	if (!ioremap_huge_disabled) {
> -		if (arch_ioremap_p4d_supported())
> -			ioremap_p4d_capable = 1;
> -		if (arch_ioremap_pud_supported())
> -			ioremap_pud_capable = 1;
> -		if (arch_ioremap_pmd_supported())
> -			ioremap_pmd_capable = 1;
> -	}
> -}
> -
> -static inline int ioremap_p4d_enabled(void)
> -{
> -	return ioremap_p4d_capable;
> -}
> -
> -static inline int ioremap_pud_enabled(void)
> -{
> -	return ioremap_pud_capable;
> -}
> -
> -static inline int ioremap_pmd_enabled(void)
> -{
> -	return ioremap_pmd_capable;
> -}
> -
> -#else	/* !CONFIG_HAVE_ARCH_HUGE_VMAP */
> -static inline int ioremap_p4d_enabled(void) { return 0; }
> -static inline int ioremap_pud_enabled(void) { return 0; }
> -static inline int ioremap_pmd_enabled(void) { return 0; }
> +#else /* CONFIG_HAVE_ARCH_HUGE_VMAP */
> +static const bool iomap_max_page_shift = PAGE_SHIFT;
>  #endif	/* CONFIG_HAVE_ARCH_HUGE_VMAP */
>  
>  static int vmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
> @@ -82,9 +49,13 @@ static int vmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
>  }
>  
>  static int vmap_try_huge_pmd(pmd_t *pmd, unsigned long addr, unsigned long end,
> -			phys_addr_t phys_addr, pgprot_t prot)
> +			phys_addr_t phys_addr, pgprot_t prot,
> +			unsigned int max_page_shift)
>  {
> -	if (!ioremap_pmd_enabled())
> +	if (max_page_shift < PMD_SHIFT)
> +		return 0;
> +
> +	if (!arch_vmap_pmd_supported(prot))
>  		return 0;
>  
>  	if ((end - addr) != PMD_SIZE)
> @@ -104,7 +75,7 @@ static int vmap_try_huge_pmd(pmd_t *pmd, unsigned long addr, unsigned long end,
>  
>  static int vmap_pmd_range(pud_t *pud, unsigned long addr, unsigned long end,
>  			phys_addr_t phys_addr, pgprot_t prot,
> -			pgtbl_mod_mask *mask)
> +			unsigned int max_page_shift, pgtbl_mod_mask *mask)
>  {
>  	pmd_t *pmd;
>  	unsigned long next;
> @@ -115,7 +86,8 @@ static int vmap_pmd_range(pud_t *pud, unsigned long addr, unsigned long end,
>  	do {
>  		next = pmd_addr_end(addr, end);
>  
> -		if (vmap_try_huge_pmd(pmd, addr, next, phys_addr, prot)) {
> +		if (vmap_try_huge_pmd(pmd, addr, next, phys_addr, prot,
> +					max_page_shift)) {
>  			*mask |= PGTBL_PMD_MODIFIED;
>  			continue;
>  		}
> @@ -127,9 +99,13 @@ static int vmap_pmd_range(pud_t *pud, unsigned long addr, unsigned long end,
>  }
>  
>  static int vmap_try_huge_pud(pud_t *pud, unsigned long addr, unsigned long end,
> -			phys_addr_t phys_addr, pgprot_t prot)
> +			phys_addr_t phys_addr, pgprot_t prot,
> +			unsigned int max_page_shift)
>  {
> -	if (!ioremap_pud_enabled())
> +	if (max_page_shift < PUD_SHIFT)
> +		return 0;
> +
> +	if (!arch_vmap_pud_supported(prot))
>  		return 0;
>  
>  	if ((end - addr) != PUD_SIZE)
> @@ -149,7 +125,7 @@ static int vmap_try_huge_pud(pud_t *pud, unsigned long addr, unsigned long end,
>  
>  static int vmap_pud_range(p4d_t *p4d, unsigned long addr, unsigned long end,
>  			phys_addr_t phys_addr, pgprot_t prot,
> -			pgtbl_mod_mask *mask)
> +			unsigned int max_page_shift, pgtbl_mod_mask *mask)
>  {
>  	pud_t *pud;
>  	unsigned long next;
> @@ -160,21 +136,27 @@ static int vmap_pud_range(p4d_t *p4d, unsigned long addr, unsigned long end,
>  	do {
>  		next = pud_addr_end(addr, end);
>  
> -		if (vmap_try_huge_pud(pud, addr, next, phys_addr, prot)) {
> +		if (vmap_try_huge_pud(pud, addr, next, phys_addr, prot,
> +					max_page_shift)) {
>  			*mask |= PGTBL_PUD_MODIFIED;
>  			continue;
>  		}
>  
> -		if (vmap_pmd_range(pud, addr, next, phys_addr, prot, mask))
> +		if (vmap_pmd_range(pud, addr, next, phys_addr, prot,
> +					max_page_shift, mask))
>  			return -ENOMEM;
>  	} while (pud++, phys_addr += (next - addr), addr = next, addr != end);
>  	return 0;
>  }
>  
>  static int vmap_try_huge_p4d(p4d_t *p4d, unsigned long addr, unsigned long end,
> -			phys_addr_t phys_addr, pgprot_t prot)
> +			phys_addr_t phys_addr, pgprot_t prot,
> +			unsigned int max_page_shift)
>  {
> -	if (!ioremap_p4d_enabled())
> +	if (max_page_shift < P4D_SHIFT)
> +		return 0;
> +
> +	if (!arch_vmap_p4d_supported(prot))
>  		return 0;
>  
>  	if ((end - addr) != P4D_SIZE)
> @@ -194,7 +176,7 @@ static int vmap_try_huge_p4d(p4d_t *p4d, unsigned long addr, unsigned long end,
>  
>  static int vmap_p4d_range(pgd_t *pgd, unsigned long addr, unsigned long end,
>  			phys_addr_t phys_addr, pgprot_t prot,
> -			pgtbl_mod_mask *mask)
> +			unsigned int max_page_shift, pgtbl_mod_mask *mask)
>  {
>  	p4d_t *p4d;
>  	unsigned long next;
> @@ -205,19 +187,22 @@ static int vmap_p4d_range(pgd_t *pgd, unsigned long addr, unsigned long end,
>  	do {
>  		next = p4d_addr_end(addr, end);
>  
> -		if (vmap_try_huge_p4d(p4d, addr, next, phys_addr, prot)) {
> +		if (vmap_try_huge_p4d(p4d, addr, next, phys_addr, prot,
> +					max_page_shift)) {
>  			*mask |= PGTBL_P4D_MODIFIED;
>  			continue;
>  		}
>  
> -		if (vmap_pud_range(p4d, addr, next, phys_addr, prot, mask))
> +		if (vmap_pud_range(p4d, addr, next, phys_addr, prot,
> +					max_page_shift, mask))
>  			return -ENOMEM;
>  	} while (p4d++, phys_addr += (next - addr), addr = next, addr != end);
>  	return 0;
>  }
>  
>  static int vmap_range(unsigned long addr, unsigned long end,
> -			phys_addr_t phys_addr, pgprot_t prot)
> +			phys_addr_t phys_addr, pgprot_t prot,
> +			unsigned int max_page_shift)
>  {
>  	pgd_t *pgd;
>  	unsigned long start;
> @@ -232,7 +217,8 @@ static int vmap_range(unsigned long addr, unsigned long end,
>  	pgd = pgd_offset_k(addr);
>  	do {
>  		next = pgd_addr_end(addr, end);
> -		err = vmap_p4d_range(pgd, addr, next, phys_addr, prot, &mask);
> +		err = vmap_p4d_range(pgd, addr, next, phys_addr, prot,
> +					max_page_shift, &mask);
>  		if (err)
>  			break;
>  	} while (pgd++, phys_addr += (next - addr), addr = next, addr != end);
> @@ -248,7 +234,7 @@ static int vmap_range(unsigned long addr, unsigned long end,
>  int ioremap_page_range(unsigned long addr,
>  		       unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
>  {
> -	return vmap_range(addr, end, phys_addr, prot);
> +	return vmap_range(addr, end, phys_addr, prot, iomap_max_page_shift);
>  }
>  
>  #ifdef CONFIG_GENERIC_IOREMAP
> 

Re: [PATCH v11 04/13] mm/ioremap: rename ioremap_*_range to vmap_*_range

[Christoph Hellwig]

Looks good,

Reviewed-by: Christoph Hellwig <hch@lst.de>

Re: [PATCH v11 01/13] mm/vmalloc: fix HUGE_VMAP regression by enabling huge pages in vmalloc_to_page

[Miaohe Lin]

Hi:
On 2021/1/26 12:44, Nicholas Piggin wrote:
> vmalloc_to_page returns NULL for addresses mapped by larger pages[*].
> Whether or not a vmap is huge depends on the architecture details,
> alignments, boot options, etc., which the caller can not be expected
> to know. Therefore HUGE_VMAP is a regression for vmalloc_to_page.
> 
> This change teaches vmalloc_to_page about larger pages, and returns
> the struct page that corresponds to the offset within the large page.
> This makes the API agnostic to mapping implementation details.
> 
> [*] As explained by commit 029c54b095995 ("mm/vmalloc.c: huge-vmap:
>     fail gracefully on unexpected huge vmap mappings")
> 
> Reviewed-by: Christoph Hellwig <hch@lst.de>
> Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
> ---
>  mm/vmalloc.c | 41 ++++++++++++++++++++++++++---------------
>  1 file changed, 26 insertions(+), 15 deletions(-)
> 
> diff --git a/mm/vmalloc.c b/mm/vmalloc.c
> index e6f352bf0498..62372f9e0167 100644
> --- a/mm/vmalloc.c
> +++ b/mm/vmalloc.c
> @@ -34,7 +34,7 @@
>  #include <linux/bitops.h>
>  #include <linux/rbtree_augmented.h>
>  #include <linux/overflow.h>
> -
> +#include <linux/pgtable.h>
>  #include <linux/uaccess.h>
>  #include <asm/tlbflush.h>
>  #include <asm/shmparam.h>
> @@ -343,7 +343,9 @@ int is_vmalloc_or_module_addr(const void *x)
>  }
>  
>  /*
> - * Walk a vmap address to the struct page it maps.
> + * Walk a vmap address to the struct page it maps. Huge vmap mappings will
> + * return the tail page that corresponds to the base page address, which
> + * matches small vmap mappings.
>   */
>  struct page *vmalloc_to_page(const void *vmalloc_addr)
>  {
> @@ -363,25 +365,33 @@ struct page *vmalloc_to_page(const void *vmalloc_addr)
>  
>  	if (pgd_none(*pgd))
>  		return NULL;
> +	if (WARN_ON_ONCE(pgd_leaf(*pgd)))
> +		return NULL; /* XXX: no allowance for huge pgd */
> +	if (WARN_ON_ONCE(pgd_bad(*pgd)))
> +		return NULL;
> +
>  	p4d = p4d_offset(pgd, addr);
>  	if (p4d_none(*p4d))
>  		return NULL;
> -	pud = pud_offset(p4d, addr);
> +	if (p4d_leaf(*p4d))
> +		return p4d_page(*p4d) + ((addr & ~P4D_MASK) >> PAGE_SHIFT);
> +	if (WARN_ON_ONCE(p4d_bad(*p4d)))
> +		return NULL;
>  
> -	/*
> -	 * Don't dereference bad PUD or PMD (below) entries. This will also
> -	 * identify huge mappings, which we may encounter on architectures
> -	 * that define CONFIG_HAVE_ARCH_HUGE_VMAP=y. Such regions will be
> -	 * identified as vmalloc addresses by is_vmalloc_addr(), but are
> -	 * not [unambiguously] associated with a struct page, so there is
> -	 * no correct value to return for them.
> -	 */
> -	WARN_ON_ONCE(pud_bad(*pud));
> -	if (pud_none(*pud) || pud_bad(*pud))
> +	pud = pud_offset(p4d, addr);
> +	if (pud_none(*pud))
> +		return NULL;
> +	if (pud_leaf(*pud))
> +		return pud_page(*pud) + ((addr & ~PUD_MASK) >> PAGE_SHIFT);
> +	if (WARN_ON_ONCE(pud_bad(*pud)))
>  		return NULL;
> +
>  	pmd = pmd_offset(pud, addr);
> -	WARN_ON_ONCE(pmd_bad(*pmd));
> -	if (pmd_none(*pmd) || pmd_bad(*pmd))
> +	if (pmd_none(*pmd))
> +		return NULL;
> +	if (pmd_leaf(*pmd))
> +		return pmd_page(*pmd) + ((addr & ~PMD_MASK) >> PAGE_SHIFT);
> +	if (WARN_ON_ONCE(pmd_bad(*pmd)))
>  		return NULL;
>  
>  	ptep = pte_offset_map(pmd, addr);
> @@ -389,6 +399,7 @@ struct page *vmalloc_to_page(const void *vmalloc_addr)
>  	if (pte_present(pte))
>  		page = pte_page(pte);
>  	pte_unmap(ptep);
> +
>  	return page;
>  }
>  EXPORT_SYMBOL(vmalloc_to_page);
> 

LGTM. Thanks.

Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>

Re: [PATCH v11 02/13] mm: apply_to_pte_range warn and fail if a large pte is encountered

[Miaohe Lin]

Hi:
On 2021/1/26 12:44, Nicholas Piggin wrote:
> apply_to_pte_range might mistake a large pte for bad, or treat it as a
> page table, resulting in a crash or corruption. Add a test to warn and
> return error if large entries are found.
> 
> Reviewed-by: Christoph Hellwig <hch@lst.de>
> Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
> ---
>  mm/memory.c | 66 +++++++++++++++++++++++++++++++++++++++--------------
>  1 file changed, 49 insertions(+), 17 deletions(-)
> 
> diff --git a/mm/memory.c b/mm/memory.c
> index feff48e1465a..672e39a72788 100644
> --- a/mm/memory.c
> +++ b/mm/memory.c
> @@ -2440,13 +2440,21 @@ static int apply_to_pmd_range(struct mm_struct *mm, pud_t *pud,
>  	}
>  	do {
>  		next = pmd_addr_end(addr, end);
> -		if (create || !pmd_none_or_clear_bad(pmd)) {
> -			err = apply_to_pte_range(mm, pmd, addr, next, fn, data,
> -						 create, mask);
> -			if (err)
> -				break;
> +		if (pmd_none(*pmd) && !create)
> +			continue;
> +		if (WARN_ON_ONCE(pmd_leaf(*pmd)))
> +			return -EINVAL;
> +		if (!pmd_none(*pmd) && WARN_ON_ONCE(pmd_bad(*pmd))) {
> +			if (!create)
> +				continue;
> +			pmd_clear_bad(pmd);
>  		}
> +		err = apply_to_pte_range(mm, pmd, addr, next,
> +					 fn, data, create, mask);
> +		if (err)
> +			break;
>  	} while (pmd++, addr = next, addr != end);
> +
>  	return err;
>  }
>  
> @@ -2468,13 +2476,21 @@ static int apply_to_pud_range(struct mm_struct *mm, p4d_t *p4d,
>  	}
>  	do {
>  		next = pud_addr_end(addr, end);
> -		if (create || !pud_none_or_clear_bad(pud)) {
> -			err = apply_to_pmd_range(mm, pud, addr, next, fn, data,
> -						 create, mask);
> -			if (err)
> -				break;
> +		if (pud_none(*pud) && !create)
> +			continue;
> +		if (WARN_ON_ONCE(pud_leaf(*pud)))
> +			return -EINVAL;
> +		if (!pud_none(*pud) && WARN_ON_ONCE(pud_bad(*pud))) {
> +			if (!create)
> +				continue;
> +			pud_clear_bad(pud);
>  		}
> +		err = apply_to_pmd_range(mm, pud, addr, next,
> +					 fn, data, create, mask);
> +		if (err)
> +			break;
>  	} while (pud++, addr = next, addr != end);
> +
>  	return err;
>  }
>  
> @@ -2496,13 +2512,21 @@ static int apply_to_p4d_range(struct mm_struct *mm, pgd_t *pgd,
>  	}
>  	do {
>  		next = p4d_addr_end(addr, end);
> -		if (create || !p4d_none_or_clear_bad(p4d)) {
> -			err = apply_to_pud_range(mm, p4d, addr, next, fn, data,
> -						 create, mask);
> -			if (err)
> -				break;
> +		if (p4d_none(*p4d) && !create)
> +			continue;
> +		if (WARN_ON_ONCE(p4d_leaf(*p4d)))
> +			return -EINVAL;
> +		if (!p4d_none(*p4d) && WARN_ON_ONCE(p4d_bad(*p4d))) {
> +			if (!create)
> +				continue;
> +			p4d_clear_bad(p4d);
>  		}
> +		err = apply_to_pud_range(mm, p4d, addr, next,
> +					 fn, data, create, mask);
> +		if (err)
> +			break;
>  	} while (p4d++, addr = next, addr != end);
> +
>  	return err;
>  }
>  
> @@ -2522,9 +2546,17 @@ static int __apply_to_page_range(struct mm_struct *mm, unsigned long addr,
>  	pgd = pgd_offset(mm, addr);
>  	do {
>  		next = pgd_addr_end(addr, end);
> -		if (!create && pgd_none_or_clear_bad(pgd))
> +		if (pgd_none(*pgd) && !create)
>  			continue;
> -		err = apply_to_p4d_range(mm, pgd, addr, next, fn, data, create, &mask);
> +		if (WARN_ON_ONCE(pgd_leaf(*pgd)))
> +			return -EINVAL;
> +		if (!pgd_none(*pgd) && WARN_ON_ONCE(pgd_bad(*pgd))) {
> +			if (!create)
> +				continue;
> +			pgd_clear_bad(pgd);
> +		}
> +		err = apply_to_p4d_range(mm, pgd, addr, next,
> +					 fn, data, create, &mask);
>  		if (err)
>  			break;
>  	} while (pgd++, addr = next, addr != end);
> 

Looks good to me, thanks.

Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>

Re: [PATCH v11 12/13] mm/vmalloc: Hugepage vmalloc mappings

[Ding Tianhong]

On 2021/1/26 12:45, Nicholas Piggin wrote:
> Support huge page vmalloc mappings. Config option HAVE_ARCH_HUGE_VMALLOC
> enables support on architectures that define HAVE_ARCH_HUGE_VMAP and
> supports PMD sized vmap mappings.
> 
> vmalloc will attempt to allocate PMD-sized pages if allocating PMD size
> or larger, and fall back to small pages if that was unsuccessful.
> 
> Architectures must ensure that any arch specific vmalloc allocations
> that require PAGE_SIZE mappings (e.g., module allocations vs strict
> module rwx) use the VM_NOHUGE flag to inhibit larger mappings.
> 
> When hugepage vmalloc mappings are enabled in the next patch, this
> reduces TLB misses by nearly 30x on a `git diff` workload on a 2-node
> POWER9 (59,800 -> 2,100) and reduces CPU cycles by 0.54%.
> 
> This can result in more internal fragmentation and memory overhead for a
> given allocation, an option nohugevmalloc is added to disable at boot.
> 
> Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
> ---
>  arch/Kconfig            |  11 ++
>  include/linux/vmalloc.h |  21 ++++
>  mm/page_alloc.c         |   5 +-
>  mm/vmalloc.c            | 215 +++++++++++++++++++++++++++++++---------
>  4 files changed, 205 insertions(+), 47 deletions(-)
> 
> diff --git a/arch/Kconfig b/arch/Kconfig
> index 24862d15f3a3..eef170e0c9b8 100644
> --- a/arch/Kconfig
> +++ b/arch/Kconfig
> @@ -724,6 +724,17 @@ config HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD
>  config HAVE_ARCH_HUGE_VMAP
>  	bool
>  
> +#
> +#  Archs that select this would be capable of PMD-sized vmaps (i.e.,
> +#  arch_vmap_pmd_supported() returns true), and they must make no assumptions
> +#  that vmalloc memory is mapped with PAGE_SIZE ptes. The VM_NO_HUGE_VMAP flag
> +#  can be used to prohibit arch-specific allocations from using hugepages to
> +#  help with this (e.g., modules may require it).
> +#
> +config HAVE_ARCH_HUGE_VMALLOC
> +	depends on HAVE_ARCH_HUGE_VMAP
> +	bool
> +
>  config ARCH_WANT_HUGE_PMD_SHARE
>  	bool
>  
> diff --git a/include/linux/vmalloc.h b/include/linux/vmalloc.h
> index 99ea72d547dc..93270adf5db5 100644
> --- a/include/linux/vmalloc.h
> +++ b/include/linux/vmalloc.h
> @@ -25,6 +25,7 @@ struct notifier_block;		/* in notifier.h */
>  #define VM_NO_GUARD		0x00000040      /* don't add guard page */
>  #define VM_KASAN		0x00000080      /* has allocated kasan shadow memory */
>  #define VM_MAP_PUT_PAGES	0x00000100	/* put pages and free array in vfree */
> +#define VM_NO_HUGE_VMAP		0x00000200	/* force PAGE_SIZE pte mapping */
> 
>  /*
>   * VM_KASAN is used slighly differently depending on CONFIG_KASAN_VMALLOC.
> @@ -59,6 +60,9 @@ struct vm_struct {
>  	unsigned long		size;
>  	unsigned long		flags;
>  	struct page		**pages;
> +#ifdef CONFIG_HAVE_ARCH_HUGE_VMALLOC
> +	unsigned int		page_order;
> +#endif
>  	unsigned int		nr_pages;
>  	phys_addr_t		phys_addr;
>  	const void		*caller;
Hi Nicholas:

Give a suggestion :)

The page order was only used to indicate the huge page flag for vm area, and only valid when
size bigger than PMD_SIZE, so can we use the vm flgas to instead of that, just like define the
new flag named VM_HUGEPAGE, it would not break the vm struct, and it is easier for me to backport the serious
patches to our own branches. (Base on the lts version).

Tianhong

> @@ -193,6 +197,22 @@ void free_vm_area(struct vm_struct *area);
>  extern struct vm_struct *remove_vm_area(const void *addr);
>  extern struct vm_struct *find_vm_area(const void *addr);
>  
> +static inline bool is_vm_area_hugepages(const void *addr)
> +{
> +	/*
> +	 * This may not 100% tell if the area is mapped with > PAGE_SIZE
> +	 * page table entries, if for some reason the architecture indicates
> +	 * larger sizes are available but decides not to use them, nothing
> +	 * prevents that. This only indicates the size of the physical page
> +	 * allocated in the vmalloc layer.
> +	 */
> +#ifdef CONFIG_HAVE_ARCH_HUGE_VMALLOC
> +	return find_vm_area(addr)->page_order > 0;
> +#else
> +	return false;
> +#endif
> +}
> +
>  #ifdef CONFIG_MMU
>  int vmap_range(unsigned long addr, unsigned long end,
>  			phys_addr_t phys_addr, pgprot_t prot,
> @@ -210,6 +230,7 @@ static inline void set_vm_flush_reset_perms(void *addr)
>  	if (vm)
>  		vm->flags |= VM_FLUSH_RESET_PERMS;
>  }
> +
>  #else
>  static inline int
>  map_kernel_range_noflush(unsigned long start, unsigned long size,
> diff --git a/mm/page_alloc.c b/mm/page_alloc.c
> index 027f6481ba59..b7a9661fa232 100644
> --- a/mm/page_alloc.c
> +++ b/mm/page_alloc.c
> @@ -72,6 +72,7 @@
>  #include <linux/padata.h>
>  #include <linux/khugepaged.h>
>  #include <linux/buffer_head.h>
> +#include <linux/vmalloc.h>
>  
>  #include <asm/sections.h>
>  #include <asm/tlbflush.h>
> @@ -8238,6 +8239,7 @@ void *__init alloc_large_system_hash(const char *tablename,
>  	void *table = NULL;
>  	gfp_t gfp_flags;
>  	bool virt;
> +	bool huge;
>  
>  	/* allow the kernel cmdline to have a say */
>  	if (!numentries) {
> @@ -8305,6 +8307,7 @@ void *__init alloc_large_system_hash(const char *tablename,
>  		} else if (get_order(size) >= MAX_ORDER || hashdist) {
>  			table = __vmalloc(size, gfp_flags);
>  			virt = true;
> +			huge = is_vm_area_hugepages(table);
>  		} else {
>  			/*
>  			 * If bucketsize is not a power-of-two, we may free
> @@ -8321,7 +8324,7 @@ void *__init alloc_large_system_hash(const char *tablename,
>  
>  	pr_info("%s hash table entries: %ld (order: %d, %lu bytes, %s)\n",
>  		tablename, 1UL << log2qty, ilog2(size) - PAGE_SHIFT, size,
> -		virt ? "vmalloc" : "linear");
> +		virt ? (huge ? "vmalloc hugepage" : "vmalloc") : "linear");
>  
>  	if (_hash_shift)
>  		*_hash_shift = log2qty;
> diff --git a/mm/vmalloc.c b/mm/vmalloc.c
> index 47ab4338cfff..e9a28de04182 100644
> --- a/mm/vmalloc.c
> +++ b/mm/vmalloc.c
> @@ -42,6 +42,19 @@
>  #include "internal.h"
>  #include "pgalloc-track.h"
>  
> +#ifdef CONFIG_HAVE_ARCH_HUGE_VMALLOC
> +static bool __ro_after_init vmap_allow_huge = true;
> +
> +static int __init set_nohugevmalloc(char *str)
> +{
> +	vmap_allow_huge = false;
> +	return 0;
> +}
> +early_param("nohugevmalloc", set_nohugevmalloc);
> +#else /* CONFIG_HAVE_ARCH_HUGE_VMALLOC */
> +static const bool vmap_allow_huge = false;
> +#endif	/* CONFIG_HAVE_ARCH_HUGE_VMALLOC */
> +
>  bool is_vmalloc_addr(const void *x)
>  {
>  	unsigned long addr = (unsigned long)x;
> @@ -483,31 +496,12 @@ static int vmap_pages_p4d_range(pgd_t *pgd, unsigned long addr,
>  	return 0;
>  }
>  
> -/**
> - * map_kernel_range_noflush - map kernel VM area with the specified pages
> - * @addr: start of the VM area to map
> - * @size: size of the VM area to map
> - * @prot: page protection flags to use
> - * @pages: pages to map
> - *
> - * Map PFN_UP(@size) pages at @addr.  The VM area @addr and @size specify should
> - * have been allocated using get_vm_area() and its friends.
> - *
> - * NOTE:
> - * This function does NOT do any cache flushing.  The caller is responsible for
> - * calling flush_cache_vmap() on to-be-mapped areas before calling this
> - * function.
> - *
> - * RETURNS:
> - * 0 on success, -errno on failure.
> - */
> -int map_kernel_range_noflush(unsigned long addr, unsigned long size,
> -			     pgprot_t prot, struct page **pages)
> +static int vmap_small_pages_range_noflush(unsigned long addr, unsigned long end,
> +		pgprot_t prot, struct page **pages)
>  {
>  	unsigned long start = addr;
> -	unsigned long end = addr + size;
> -	unsigned long next;
>  	pgd_t *pgd;
> +	unsigned long next;
>  	int err = 0;
>  	int nr = 0;
>  	pgtbl_mod_mask mask = 0;
> @@ -529,6 +523,66 @@ int map_kernel_range_noflush(unsigned long addr, unsigned long size,
>  	return 0;
>  }
>  
> +static int vmap_pages_range_noflush(unsigned long addr, unsigned long end,
> +		pgprot_t prot, struct page **pages, unsigned int page_shift)
> +{
> +	unsigned int i, nr = (end - addr) >> PAGE_SHIFT;
> +
> +	WARN_ON(page_shift < PAGE_SHIFT);
> +
> +	if (!IS_ENABLED(CONFIG_HAVE_ARCH_HUGE_VMALLOC) ||
> +			page_shift == PAGE_SHIFT)
> +		return vmap_small_pages_range_noflush(addr, end, prot, pages);
> +
> +	for (i = 0; i < nr; i += 1U << (page_shift - PAGE_SHIFT)) {
> +		int err;
> +
> +		err = vmap_range_noflush(addr, addr + (1UL << page_shift),
> +					__pa(page_address(pages[i])), prot,
> +					page_shift);
> +		if (err)
> +			return err;
> +
> +		addr += 1UL << page_shift;
> +	}
> +
> +	return 0;
> +}
> +
> +static int vmap_pages_range(unsigned long addr, unsigned long end,
> +		pgprot_t prot, struct page **pages, unsigned int page_shift)
> +{
> +	int err;
> +
> +	err = vmap_pages_range_noflush(addr, end, prot, pages, page_shift);
> +	flush_cache_vmap(addr, end);
> +	return err;
> +}
> +
> +/**
> + * map_kernel_range_noflush - map kernel VM area with the specified pages
> + * @addr: start of the VM area to map
> + * @size: size of the VM area to map
> + * @prot: page protection flags to use
> + * @pages: pages to map
> + *
> + * Map PFN_UP(@size) pages at @addr.  The VM area @addr and @size specify should
> + * have been allocated using get_vm_area() and its friends.
> + *
> + * NOTE:
> + * This function does NOT do any cache flushing.  The caller is responsible for
> + * calling flush_cache_vmap() on to-be-mapped areas before calling this
> + * function.
> + *
> + * RETURNS:
> + * 0 on success, -errno on failure.
> + */
> +int map_kernel_range_noflush(unsigned long addr, unsigned long size,
> +			     pgprot_t prot, struct page **pages)
> +{
> +	return vmap_pages_range_noflush(addr, addr + size, prot, pages, PAGE_SHIFT);
> +}
> +
>  int map_kernel_range(unsigned long start, unsigned long size, pgprot_t prot,
>  		struct page **pages)
>  {
> @@ -2112,6 +2166,24 @@ EXPORT_SYMBOL(vm_map_ram);
>  
>  static struct vm_struct *vmlist __initdata;
>  
> +static inline unsigned int vm_area_page_order(struct vm_struct *vm)
> +{
> +#ifdef CONFIG_HAVE_ARCH_HUGE_VMALLOC
> +	return vm->page_order;
> +#else
> +	return 0;
> +#endif
> +}
> +
> +static inline void set_vm_area_page_order(struct vm_struct *vm, unsigned int order)
> +{
> +#ifdef CONFIG_HAVE_ARCH_HUGE_VMALLOC
> +	vm->page_order = order;
> +#else
> +	BUG_ON(order != 0);
> +#endif
> +}
> +
>  /**
>   * vm_area_add_early - add vmap area early during boot
>   * @vm: vm_struct to add
> @@ -2422,6 +2494,7 @@ static inline void set_area_direct_map(const struct vm_struct *area,
>  {
>  	int i;
>  
> +	/* HUGE_VMALLOC passes small pages to set_direct_map */
>  	for (i = 0; i < area->nr_pages; i++)
>  		if (page_address(area->pages[i]))
>  			set_direct_map(area->pages[i]);
> @@ -2431,6 +2504,7 @@ static inline void set_area_direct_map(const struct vm_struct *area,
>  static void vm_remove_mappings(struct vm_struct *area, int deallocate_pages)
>  {
>  	unsigned long start = ULONG_MAX, end = 0;
> +	unsigned int page_order = vm_area_page_order(area);
>  	int flush_reset = area->flags & VM_FLUSH_RESET_PERMS;
>  	int flush_dmap = 0;
>  	int i;
> @@ -2455,11 +2529,14 @@ static void vm_remove_mappings(struct vm_struct *area, int deallocate_pages)
>  	 * map. Find the start and end range of the direct mappings to make sure
>  	 * the vm_unmap_aliases() flush includes the direct map.
>  	 */
> -	for (i = 0; i < area->nr_pages; i++) {
> +	for (i = 0; i < area->nr_pages; i += 1U << page_order) {
>  		unsigned long addr = (unsigned long)page_address(area->pages[i]);
>  		if (addr) {
> +			unsigned long page_size;
> +
> +			page_size = PAGE_SIZE << page_order;
>  			start = min(addr, start);
> -			end = max(addr + PAGE_SIZE, end);
> +			end = max(addr + page_size, end);
>  			flush_dmap = 1;
>  		}
>  	}
> @@ -2500,13 +2577,14 @@ static void __vunmap(const void *addr, int deallocate_pages)
>  	vm_remove_mappings(area, deallocate_pages);
>  
>  	if (deallocate_pages) {
> +		unsigned int page_order = vm_area_page_order(area);
>  		int i;
>  
> -		for (i = 0; i < area->nr_pages; i++) {
> +		for (i = 0; i < area->nr_pages; i += 1U << page_order) {
>  			struct page *page = area->pages[i];
>  
>  			BUG_ON(!page);
> -			__free_pages(page, 0);
> +			__free_pages(page, page_order);
>  		}
>  		atomic_long_sub(area->nr_pages, &nr_vmalloc_pages);
>  
> @@ -2697,15 +2775,19 @@ EXPORT_SYMBOL_GPL(vmap_pfn);
>  #endif /* CONFIG_VMAP_PFN */
>  
>  static void *__vmalloc_area_node(struct vm_struct *area, gfp_t gfp_mask,
> -				 pgprot_t prot, int node)
> +				 pgprot_t prot, unsigned int page_shift,
> +				 int node)
>  {
>  	const gfp_t nested_gfp = (gfp_mask & GFP_RECLAIM_MASK) | __GFP_ZERO;
> -	unsigned int nr_pages = get_vm_area_size(area) >> PAGE_SHIFT;
> +	unsigned long addr = (unsigned long)area->addr;
> +	unsigned long size = get_vm_area_size(area);
>  	unsigned long array_size;
> -	unsigned int i;
> +	unsigned int nr_small_pages = size >> PAGE_SHIFT;
> +	unsigned int page_order;
>  	struct page **pages;
> +	unsigned int i;
>  
> -	array_size = (unsigned long)nr_pages * sizeof(struct page *);
> +	array_size = (unsigned long)nr_small_pages * sizeof(struct page *);
>  	gfp_mask |= __GFP_NOWARN;
>  	if (!(gfp_mask & (GFP_DMA | GFP_DMA32)))
>  		gfp_mask |= __GFP_HIGHMEM;
> @@ -2724,30 +2806,37 @@ static void *__vmalloc_area_node(struct vm_struct *area, gfp_t gfp_mask,
>  	}
>  
>  	area->pages = pages;
> -	area->nr_pages = nr_pages;
> +	area->nr_pages = nr_small_pages;
> +	set_vm_area_page_order(area, page_shift - PAGE_SHIFT);
>  
> -	for (i = 0; i < area->nr_pages; i++) {
> -		struct page *page;
> +	page_order = vm_area_page_order(area);
>  
> -		if (node == NUMA_NO_NODE)
> -			page = alloc_page(gfp_mask);
> -		else
> -			page = alloc_pages_node(node, gfp_mask, 0);
> +	/*
> +	 * Careful, we allocate and map page_order pages, but tracking is done
> +	 * per PAGE_SIZE page so as to keep the vm_struct APIs independent of
> +	 * the physical/mapped size.
> +	 */
> +	for (i = 0; i < area->nr_pages; i += 1U << page_order) {
> +		struct page *page;
> +		int p;
>  
> +		page = alloc_pages_node(node, gfp_mask, page_order);
>  		if (unlikely(!page)) {
>  			/* Successfully allocated i pages, free them in __vfree() */
>  			area->nr_pages = i;
>  			atomic_long_add(area->nr_pages, &nr_vmalloc_pages);
>  			goto fail;
>  		}
> -		area->pages[i] = page;
> +
> +		for (p = 0; p < (1U << page_order); p++)
> +			area->pages[i + p] = page + p;
> +
>  		if (gfpflags_allow_blocking(gfp_mask))
>  			cond_resched();
>  	}
>  	atomic_long_add(area->nr_pages, &nr_vmalloc_pages);
>  
> -	if (map_kernel_range((unsigned long)area->addr, get_vm_area_size(area),
> -			prot, pages) < 0)
> +	if (vmap_pages_range(addr, addr + size, prot, pages, page_shift) < 0)
>  		goto fail;
>  
>  	return area->addr;
> @@ -2755,7 +2844,7 @@ static void *__vmalloc_area_node(struct vm_struct *area, gfp_t gfp_mask,
>  fail:
>  	warn_alloc(gfp_mask, NULL,
>  			  "vmalloc: allocation failure, allocated %ld of %ld bytes",
> -			  (area->nr_pages*PAGE_SIZE), area->size);
> +			  (area->nr_pages*PAGE_SIZE), size);
>  	__vfree(area->addr);
>  	return NULL;
>  }
> @@ -2786,19 +2875,43 @@ void *__vmalloc_node_range(unsigned long size, unsigned long align,
>  	struct vm_struct *area;
>  	void *addr;
>  	unsigned long real_size = size;
> +	unsigned long real_align = align;
> +	unsigned int shift = PAGE_SHIFT;
>  
> -	size = PAGE_ALIGN(size);
>  	if (!size || (size >> PAGE_SHIFT) > totalram_pages())
>  		goto fail;
>  
> -	area = __get_vm_area_node(real_size, align, VM_ALLOC | VM_UNINITIALIZED |
> +	if (vmap_allow_huge && !(vm_flags & VM_NO_HUGE_VMAP) &&
> +			arch_vmap_pmd_supported(prot)) {
> +		unsigned long size_per_node;
> +
> +		/*
> +		 * Try huge pages. Only try for PAGE_KERNEL allocations,
> +		 * others like modules don't yet expect huge pages in
> +		 * their allocations due to apply_to_page_range not
> +		 * supporting them.
> +		 */
> +
> +		size_per_node = size;
> +		if (node == NUMA_NO_NODE)
> +			size_per_node /= num_online_nodes();
> +		if (size_per_node >= PMD_SIZE) {
> +			shift = PMD_SHIFT;
> +			align = max(real_align, 1UL << shift);
> +			size = ALIGN(real_size, 1UL << shift);
> +		}
> +	}
> +
> +again:
> +	size = PAGE_ALIGN(size);
> +	area = __get_vm_area_node(size, align, VM_ALLOC | VM_UNINITIALIZED |
>  				vm_flags, start, end, node, gfp_mask, caller);
>  	if (!area)
>  		goto fail;
>  
> -	addr = __vmalloc_area_node(area, gfp_mask, prot, node);
> +	addr = __vmalloc_area_node(area, gfp_mask, prot, shift, node);
>  	if (!addr)
> -		return NULL;
> +		goto fail;
>  
>  	/*
>  	 * In this function, newly allocated vm_struct has VM_UNINITIALIZED
> @@ -2812,8 +2925,18 @@ void *__vmalloc_node_range(unsigned long size, unsigned long align,
>  	return addr;
>  
>  fail:
> -	warn_alloc(gfp_mask, NULL,
> +	if (shift > PAGE_SHIFT) {
> +		shift = PAGE_SHIFT;
> +		align = real_align;
> +		size = real_size;
> +		goto again;
> +	}
> +
> +	if (!area) {
> +		/* Warn for area allocation, page allocations already warn */
> +		warn_alloc(gfp_mask, NULL,
>  			  "vmalloc: allocation failure: %lu bytes", real_size);
> +	}
>  	return NULL;
>  }
>  
> 

Re: [PATCH v11 12/13] mm/vmalloc: Hugepage vmalloc mappings

[Nicholas Piggin]

Excerpts from Ding Tianhong's message of January 26, 2021 4:59 pm:
> On 2021/1/26 12:45, Nicholas Piggin wrote:
>> Support huge page vmalloc mappings. Config option HAVE_ARCH_HUGE_VMALLOC
>> enables support on architectures that define HAVE_ARCH_HUGE_VMAP and
>> supports PMD sized vmap mappings.
>> 
>> vmalloc will attempt to allocate PMD-sized pages if allocating PMD size
>> or larger, and fall back to small pages if that was unsuccessful.
>> 
>> Architectures must ensure that any arch specific vmalloc allocations
>> that require PAGE_SIZE mappings (e.g., module allocations vs strict
>> module rwx) use the VM_NOHUGE flag to inhibit larger mappings.
>> 
>> When hugepage vmalloc mappings are enabled in the next patch, this
>> reduces TLB misses by nearly 30x on a `git diff` workload on a 2-node
>> POWER9 (59,800 -> 2,100) and reduces CPU cycles by 0.54%.
>> 
>> This can result in more internal fragmentation and memory overhead for a
>> given allocation, an option nohugevmalloc is added to disable at boot.
>> 
>> Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
>> ---
>>  arch/Kconfig            |  11 ++
>>  include/linux/vmalloc.h |  21 ++++
>>  mm/page_alloc.c         |   5 +-
>>  mm/vmalloc.c            | 215 +++++++++++++++++++++++++++++++---------
>>  4 files changed, 205 insertions(+), 47 deletions(-)
>> 
>> diff --git a/arch/Kconfig b/arch/Kconfig
>> index 24862d15f3a3..eef170e0c9b8 100644
>> --- a/arch/Kconfig
>> +++ b/arch/Kconfig
>> @@ -724,6 +724,17 @@ config HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD
>>  config HAVE_ARCH_HUGE_VMAP
>>  	bool
>>  
>> +#
>> +#  Archs that select this would be capable of PMD-sized vmaps (i.e.,
>> +#  arch_vmap_pmd_supported() returns true), and they must make no assumptions
>> +#  that vmalloc memory is mapped with PAGE_SIZE ptes. The VM_NO_HUGE_VMAP flag
>> +#  can be used to prohibit arch-specific allocations from using hugepages to
>> +#  help with this (e.g., modules may require it).
>> +#
>> +config HAVE_ARCH_HUGE_VMALLOC
>> +	depends on HAVE_ARCH_HUGE_VMAP
>> +	bool
>> +
>>  config ARCH_WANT_HUGE_PMD_SHARE
>>  	bool
>>  
>> diff --git a/include/linux/vmalloc.h b/include/linux/vmalloc.h
>> index 99ea72d547dc..93270adf5db5 100644
>> --- a/include/linux/vmalloc.h
>> +++ b/include/linux/vmalloc.h
>> @@ -25,6 +25,7 @@ struct notifier_block;		/* in notifier.h */
>>  #define VM_NO_GUARD		0x00000040      /* don't add guard page */
>>  #define VM_KASAN		0x00000080      /* has allocated kasan shadow memory */
>>  #define VM_MAP_PUT_PAGES	0x00000100	/* put pages and free array in vfree */
>> +#define VM_NO_HUGE_VMAP		0x00000200	/* force PAGE_SIZE pte mapping */
>> 
>>  /*
>>   * VM_KASAN is used slighly differently depending on CONFIG_KASAN_VMALLOC.
>> @@ -59,6 +60,9 @@ struct vm_struct {
>>  	unsigned long		size;
>>  	unsigned long		flags;
>>  	struct page		**pages;
>> +#ifdef CONFIG_HAVE_ARCH_HUGE_VMALLOC
>> +	unsigned int		page_order;
>> +#endif
>>  	unsigned int		nr_pages;
>>  	phys_addr_t		phys_addr;
>>  	const void		*caller;
> Hi Nicholas:
> 
> Give a suggestion :)
> 
> The page order was only used to indicate the huge page flag for vm area, and only valid when
> size bigger than PMD_SIZE, so can we use the vm flgas to instead of that, just like define the
> new flag named VM_HUGEPAGE, it would not break the vm struct, and it is easier for me to backport the serious
> patches to our own branches. (Base on the lts version).

Hmm, it might be possible. I'm not sure if 1GB vmallocs will be used any 
time soon (or maybe they will for edge case configurations? It would be 
trivial to add support for).

The other concern I have is that Christophe IIRC was asking about 
implementing a mapping for PPC which used TLB mappings that were 
different than kernel page table tree size. Although I guess we could 
deal with that when it comes.

I like the flexibility of page_order though. How hard would it be for 
you to do the backport with VM_HUGEPAGE yourself?

I should also say, thanks for all the review and testing from the Huawei 
team. Do you have an x86 patch?

Thanks,
Nick

Re: [PATCH v11 12/13] mm/vmalloc: Hugepage vmalloc mappings

[Ding Tianhong]

On 2021/1/26 17:47, Nicholas Piggin wrote:
> Excerpts from Ding Tianhong's message of January 26, 2021 4:59 pm:
>> On 2021/1/26 12:45, Nicholas Piggin wrote:
>>> Support huge page vmalloc mappings. Config option HAVE_ARCH_HUGE_VMALLOC
>>> enables support on architectures that define HAVE_ARCH_HUGE_VMAP and
>>> supports PMD sized vmap mappings.
>>>
>>> vmalloc will attempt to allocate PMD-sized pages if allocating PMD size
>>> or larger, and fall back to small pages if that was unsuccessful.
>>>
>>> Architectures must ensure that any arch specific vmalloc allocations
>>> that require PAGE_SIZE mappings (e.g., module allocations vs strict
>>> module rwx) use the VM_NOHUGE flag to inhibit larger mappings.
>>>
>>> When hugepage vmalloc mappings are enabled in the next patch, this
>>> reduces TLB misses by nearly 30x on a `git diff` workload on a 2-node
>>> POWER9 (59,800 -> 2,100) and reduces CPU cycles by 0.54%.
>>>
>>> This can result in more internal fragmentation and memory overhead for a
>>> given allocation, an option nohugevmalloc is added to disable at boot.
>>>
>>> Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
>>> ---
>>>  arch/Kconfig            |  11 ++
>>>  include/linux/vmalloc.h |  21 ++++
>>>  mm/page_alloc.c         |   5 +-
>>>  mm/vmalloc.c            | 215 +++++++++++++++++++++++++++++++---------
>>>  4 files changed, 205 insertions(+), 47 deletions(-)
>>>
>>> diff --git a/arch/Kconfig b/arch/Kconfig
>>> index 24862d15f3a3..eef170e0c9b8 100644
>>> --- a/arch/Kconfig
>>> +++ b/arch/Kconfig
>>> @@ -724,6 +724,17 @@ config HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD
>>>  config HAVE_ARCH_HUGE_VMAP
>>>  	bool
>>>  
>>> +#
>>> +#  Archs that select this would be capable of PMD-sized vmaps (i.e.,
>>> +#  arch_vmap_pmd_supported() returns true), and they must make no assumptions
>>> +#  that vmalloc memory is mapped with PAGE_SIZE ptes. The VM_NO_HUGE_VMAP flag
>>> +#  can be used to prohibit arch-specific allocations from using hugepages to
>>> +#  help with this (e.g., modules may require it).
>>> +#
>>> +config HAVE_ARCH_HUGE_VMALLOC
>>> +	depends on HAVE_ARCH_HUGE_VMAP
>>> +	bool
>>> +
>>>  config ARCH_WANT_HUGE_PMD_SHARE
>>>  	bool
>>>  
>>> diff --git a/include/linux/vmalloc.h b/include/linux/vmalloc.h
>>> index 99ea72d547dc..93270adf5db5 100644
>>> --- a/include/linux/vmalloc.h
>>> +++ b/include/linux/vmalloc.h
>>> @@ -25,6 +25,7 @@ struct notifier_block;		/* in notifier.h */
>>>  #define VM_NO_GUARD		0x00000040      /* don't add guard page */
>>>  #define VM_KASAN		0x00000080      /* has allocated kasan shadow memory */
>>>  #define VM_MAP_PUT_PAGES	0x00000100	/* put pages and free array in vfree */
>>> +#define VM_NO_HUGE_VMAP		0x00000200	/* force PAGE_SIZE pte mapping */
>>>
>>>  /*
>>>   * VM_KASAN is used slighly differently depending on CONFIG_KASAN_VMALLOC.
>>> @@ -59,6 +60,9 @@ struct vm_struct {
>>>  	unsigned long		size;
>>>  	unsigned long		flags;
>>>  	struct page		**pages;
>>> +#ifdef CONFIG_HAVE_ARCH_HUGE_VMALLOC
>>> +	unsigned int		page_order;
>>> +#endif
>>>  	unsigned int		nr_pages;
>>>  	phys_addr_t		phys_addr;
>>>  	const void		*caller;
>> Hi Nicholas:
>>
>> Give a suggestion :)
>>
>> The page order was only used to indicate the huge page flag for vm area, and only valid when
>> size bigger than PMD_SIZE, so can we use the vm flgas to instead of that, just like define the
>> new flag named VM_HUGEPAGE, it would not break the vm struct, and it is easier for me to backport the serious
>> patches to our own branches. (Base on the lts version).
> 
> Hmm, it might be possible. I'm not sure if 1GB vmallocs will be used any 
> time soon (or maybe they will for edge case configurations? It would be 
> trivial to add support for).
> 

1GB vmallocs is really crazy, but maybe used for future. :)

> The other concern I have is that Christophe IIRC was asking about 
> implementing a mapping for PPC which used TLB mappings that were 
> different than kernel page table tree size. Although I guess we could 
> deal with that when it comes.
> 

I didn't check the PPC platform, but a agree with you.

> I like the flexibility of page_order though. How hard would it be for 
> you to do the backport with VM_HUGEPAGE yourself?
> 

Yes, i can fix it with VM_HUGEPAGE for my own branch.

> I should also say, thanks for all the review and testing from the Huawei 
> team. Do you have an x86 patch?
I only enable and use it for x86 and aarch64 platform, this serious patches is
really help us a lot. Thanks.

Ding

> Thanks,
> Nick
> .
> 

Re: [PATCH v11 05/13] mm: HUGE_VMAP arch support cleanup

[kernel test robot]

[-- Attachment #1: Type: text/plain, Size: 13953 bytes --]

Hi Nicholas,

I love your patch! Yet something to improve:

[auto build test ERROR on powerpc/next]
[also build test ERROR on arm64/for-next/core v5.11-rc5 next-20210125]
[cannot apply to hnaz-linux-mm/master]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Nicholas-Piggin/huge-vmalloc-mappings/20210126-143141
base:   https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git next
config: x86_64-randconfig-a002-20210126 (attached as .config)
compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project 925ae8c790c7e354f12ec14a6cac6aa49fc75b29)
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # install x86_64 cross compiling tool for clang build
        # apt-get install binutils-x86-64-linux-gnu
        # https://github.com/0day-ci/linux/commit/e43d3c665212ea34b790ab8d150bbde9d42e35b8
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Nicholas-Piggin/huge-vmalloc-mappings/20210126-143141
        git checkout e43d3c665212ea34b790ab8d150bbde9d42e35b8
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All errors (new ones prefixed by >>):

>> mm/debug_vm_pgtable.c:221:7: error: implicit declaration of function 'arch_ioremap_pmd_supported' [-Werror,-Wimplicit-function-declaration]
           if (!arch_ioremap_pmd_supported())
                ^
   mm/debug_vm_pgtable.c:221:7: note: did you mean 'arch_vmap_pmd_supported'?
   arch/x86/include/asm/vmalloc.h:10:6: note: 'arch_vmap_pmd_supported' declared here
   bool arch_vmap_pmd_supported(pgprot_t prot);
        ^
>> mm/debug_vm_pgtable.c:343:7: error: implicit declaration of function 'arch_ioremap_pud_supported' [-Werror,-Wimplicit-function-declaration]
           if (!arch_ioremap_pud_supported())
                ^
   mm/debug_vm_pgtable.c:343:7: note: did you mean 'arch_vmap_pud_supported'?
   arch/x86/include/asm/vmalloc.h:9:6: note: 'arch_vmap_pud_supported' declared here
   bool arch_vmap_pud_supported(pgprot_t prot);
        ^
   2 errors generated.


vim +/arch_ioremap_pmd_supported +221 mm/debug_vm_pgtable.c

a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  215  
85a144632dcc71 Aneesh Kumar K.V  2020-10-15  216  #ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  217  static void __init pmd_huge_tests(pmd_t *pmdp, unsigned long pfn, pgprot_t prot)
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  218  {
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  219  	pmd_t pmd;
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  220  
85a144632dcc71 Aneesh Kumar K.V  2020-10-15 @221  	if (!arch_ioremap_pmd_supported())
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  222  		return;
6315df41afccf1 Anshuman Khandual 2020-08-06  223  
6315df41afccf1 Anshuman Khandual 2020-08-06  224  	pr_debug("Validating PMD huge\n");
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  225  	/*
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  226  	 * X86 defined pmd_set_huge() verifies that the given
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  227  	 * PMD is not a populated non-leaf entry.
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  228  	 */
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  229  	WRITE_ONCE(*pmdp, __pmd(0));
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  230  	WARN_ON(!pmd_set_huge(pmdp, __pfn_to_phys(pfn), prot));
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  231  	WARN_ON(!pmd_clear_huge(pmdp));
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  232  	pmd = READ_ONCE(*pmdp);
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  233  	WARN_ON(!pmd_none(pmd));
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  234  }
85a144632dcc71 Aneesh Kumar K.V  2020-10-15  235  #else /* CONFIG_HAVE_ARCH_HUGE_VMAP */
85a144632dcc71 Aneesh Kumar K.V  2020-10-15  236  static void __init pmd_huge_tests(pmd_t *pmdp, unsigned long pfn, pgprot_t prot) { }
85a144632dcc71 Aneesh Kumar K.V  2020-10-15  237  #endif /* CONFIG_HAVE_ARCH_HUGE_VMAP */
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  238  
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  239  static void __init pmd_savedwrite_tests(unsigned long pfn, pgprot_t prot)
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  240  {
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  241  	pmd_t pmd = pfn_pmd(pfn, prot);
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  242  
4200605b1f80e4 Aneesh Kumar K.V  2020-10-15  243  	if (!IS_ENABLED(CONFIG_NUMA_BALANCING))
4200605b1f80e4 Aneesh Kumar K.V  2020-10-15  244  		return;
4200605b1f80e4 Aneesh Kumar K.V  2020-10-15  245  
6315df41afccf1 Anshuman Khandual 2020-08-06  246  	pr_debug("Validating PMD saved write\n");
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  247  	WARN_ON(!pmd_savedwrite(pmd_mk_savedwrite(pmd_clear_savedwrite(pmd))));
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  248  	WARN_ON(pmd_savedwrite(pmd_clear_savedwrite(pmd_mk_savedwrite(pmd))));
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  249  }
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  250  
399145f9eb6c67 Anshuman Khandual 2020-06-04  251  #ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD
399145f9eb6c67 Anshuman Khandual 2020-06-04  252  static void __init pud_basic_tests(unsigned long pfn, pgprot_t prot)
399145f9eb6c67 Anshuman Khandual 2020-06-04  253  {
399145f9eb6c67 Anshuman Khandual 2020-06-04  254  	pud_t pud = pfn_pud(pfn, prot);
399145f9eb6c67 Anshuman Khandual 2020-06-04  255  
787d563b8642f3 Aneesh Kumar K.V  2020-06-10  256  	if (!has_transparent_hugepage())
787d563b8642f3 Aneesh Kumar K.V  2020-06-10  257  		return;
787d563b8642f3 Aneesh Kumar K.V  2020-06-10  258  
6315df41afccf1 Anshuman Khandual 2020-08-06  259  	pr_debug("Validating PUD basic\n");
399145f9eb6c67 Anshuman Khandual 2020-06-04  260  	WARN_ON(!pud_same(pud, pud));
399145f9eb6c67 Anshuman Khandual 2020-06-04  261  	WARN_ON(!pud_young(pud_mkyoung(pud_mkold(pud))));
399145f9eb6c67 Anshuman Khandual 2020-06-04  262  	WARN_ON(!pud_write(pud_mkwrite(pud_wrprotect(pud))));
399145f9eb6c67 Anshuman Khandual 2020-06-04  263  	WARN_ON(pud_write(pud_wrprotect(pud_mkwrite(pud))));
399145f9eb6c67 Anshuman Khandual 2020-06-04  264  	WARN_ON(pud_young(pud_mkold(pud_mkyoung(pud))));
399145f9eb6c67 Anshuman Khandual 2020-06-04  265  
399145f9eb6c67 Anshuman Khandual 2020-06-04  266  	if (mm_pmd_folded(mm))
399145f9eb6c67 Anshuman Khandual 2020-06-04  267  		return;
399145f9eb6c67 Anshuman Khandual 2020-06-04  268  
399145f9eb6c67 Anshuman Khandual 2020-06-04  269  	/*
399145f9eb6c67 Anshuman Khandual 2020-06-04  270  	 * A huge page does not point to next level page table
399145f9eb6c67 Anshuman Khandual 2020-06-04  271  	 * entry. Hence this must qualify as pud_bad().
399145f9eb6c67 Anshuman Khandual 2020-06-04  272  	 */
399145f9eb6c67 Anshuman Khandual 2020-06-04  273  	WARN_ON(!pud_bad(pud_mkhuge(pud)));
399145f9eb6c67 Anshuman Khandual 2020-06-04  274  }
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  275  
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  276  static void __init pud_advanced_tests(struct mm_struct *mm,
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  277  				      struct vm_area_struct *vma, pud_t *pudp,
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  278  				      unsigned long pfn, unsigned long vaddr,
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  279  				      pgprot_t prot)
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  280  {
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  281  	pud_t pud = pfn_pud(pfn, prot);
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  282  
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  283  	if (!has_transparent_hugepage())
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  284  		return;
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  285  
6315df41afccf1 Anshuman Khandual 2020-08-06  286  	pr_debug("Validating PUD advanced\n");
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  287  	/* Align the address wrt HPAGE_PUD_SIZE */
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  288  	vaddr = (vaddr & HPAGE_PUD_MASK) + HPAGE_PUD_SIZE;
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  289  
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  290  	set_pud_at(mm, vaddr, pudp, pud);
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  291  	pudp_set_wrprotect(mm, vaddr, pudp);
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  292  	pud = READ_ONCE(*pudp);
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  293  	WARN_ON(pud_write(pud));
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  294  
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  295  #ifndef __PAGETABLE_PMD_FOLDED
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  296  	pudp_huge_get_and_clear(mm, vaddr, pudp);
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  297  	pud = READ_ONCE(*pudp);
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  298  	WARN_ON(!pud_none(pud));
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  299  #endif /* __PAGETABLE_PMD_FOLDED */
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  300  	pud = pfn_pud(pfn, prot);
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  301  	pud = pud_wrprotect(pud);
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  302  	pud = pud_mkclean(pud);
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  303  	set_pud_at(mm, vaddr, pudp, pud);
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  304  	pud = pud_mkwrite(pud);
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  305  	pud = pud_mkdirty(pud);
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  306  	pudp_set_access_flags(vma, vaddr, pudp, pud, 1);
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  307  	pud = READ_ONCE(*pudp);
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  308  	WARN_ON(!(pud_write(pud) && pud_dirty(pud)));
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  309  
c3824e18d3f394 Aneesh Kumar K.V  2020-10-15  310  #ifndef __PAGETABLE_PMD_FOLDED
c3824e18d3f394 Aneesh Kumar K.V  2020-10-15  311  	pudp_huge_get_and_clear_full(mm, vaddr, pudp, 1);
c3824e18d3f394 Aneesh Kumar K.V  2020-10-15  312  	pud = READ_ONCE(*pudp);
c3824e18d3f394 Aneesh Kumar K.V  2020-10-15  313  	WARN_ON(!pud_none(pud));
c3824e18d3f394 Aneesh Kumar K.V  2020-10-15  314  #endif /* __PAGETABLE_PMD_FOLDED */
c3824e18d3f394 Aneesh Kumar K.V  2020-10-15  315  
c3824e18d3f394 Aneesh Kumar K.V  2020-10-15  316  	pud = pfn_pud(pfn, prot);
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  317  	pud = pud_mkyoung(pud);
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  318  	set_pud_at(mm, vaddr, pudp, pud);
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  319  	pudp_test_and_clear_young(vma, vaddr, pudp);
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  320  	pud = READ_ONCE(*pudp);
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  321  	WARN_ON(pud_young(pud));
13af0506303323 Aneesh Kumar K.V  2020-10-15  322  
13af0506303323 Aneesh Kumar K.V  2020-10-15  323  	pudp_huge_get_and_clear(mm, vaddr, pudp);
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  324  }
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  325  
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  326  static void __init pud_leaf_tests(unsigned long pfn, pgprot_t prot)
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  327  {
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  328  	pud_t pud = pfn_pud(pfn, prot);
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  329  
6315df41afccf1 Anshuman Khandual 2020-08-06  330  	pr_debug("Validating PUD leaf\n");
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  331  	/*
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  332  	 * PUD based THP is a leaf entry.
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  333  	 */
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  334  	pud = pud_mkhuge(pud);
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  335  	WARN_ON(!pud_leaf(pud));
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  336  }
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  337  
85a144632dcc71 Aneesh Kumar K.V  2020-10-15  338  #ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  339  static void __init pud_huge_tests(pud_t *pudp, unsigned long pfn, pgprot_t prot)
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  340  {
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  341  	pud_t pud;
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  342  
85a144632dcc71 Aneesh Kumar K.V  2020-10-15 @343  	if (!arch_ioremap_pud_supported())
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  344  		return;
6315df41afccf1 Anshuman Khandual 2020-08-06  345  
6315df41afccf1 Anshuman Khandual 2020-08-06  346  	pr_debug("Validating PUD huge\n");
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  347  	/*
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  348  	 * X86 defined pud_set_huge() verifies that the given
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  349  	 * PUD is not a populated non-leaf entry.
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  350  	 */
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  351  	WRITE_ONCE(*pudp, __pud(0));
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  352  	WARN_ON(!pud_set_huge(pudp, __pfn_to_phys(pfn), prot));
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  353  	WARN_ON(!pud_clear_huge(pudp));
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  354  	pud = READ_ONCE(*pudp);
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  355  	WARN_ON(!pud_none(pud));
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  356  }
85a144632dcc71 Aneesh Kumar K.V  2020-10-15  357  #else /* !CONFIG_HAVE_ARCH_HUGE_VMAP */
85a144632dcc71 Aneesh Kumar K.V  2020-10-15  358  static void __init pud_huge_tests(pud_t *pudp, unsigned long pfn, pgprot_t prot) { }
85a144632dcc71 Aneesh Kumar K.V  2020-10-15  359  #endif /* !CONFIG_HAVE_ARCH_HUGE_VMAP */
85a144632dcc71 Aneesh Kumar K.V  2020-10-15  360  

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org

[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 42992 bytes --]

Re: [PATCH v11 03/13] mm/vmalloc: rename vmap_*_range vmap_pages_*_range

[Miaohe Lin]

Hi:
On 2021/1/26 12:45, Nicholas Piggin wrote:
> The vmalloc mapper operates on a struct page * array rather than a
> linear physical address, re-name it to make this distinction clear.
> 
> Reviewed-by: Christoph Hellwig <hch@lst.de>
> Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
> ---
>  mm/vmalloc.c | 16 ++++++++--------
>  1 file changed, 8 insertions(+), 8 deletions(-)
> 
> diff --git a/mm/vmalloc.c b/mm/vmalloc.c
> index 62372f9e0167..7f2f36116980 100644
> --- a/mm/vmalloc.c
> +++ b/mm/vmalloc.c
> @@ -189,7 +189,7 @@ void unmap_kernel_range_noflush(unsigned long start, unsigned long size)
>  		arch_sync_kernel_mappings(start, end);
>  }
>  
> -static int vmap_pte_range(pmd_t *pmd, unsigned long addr,
> +static int vmap_pages_pte_range(pmd_t *pmd, unsigned long addr,
>  		unsigned long end, pgprot_t prot, struct page **pages, int *nr,
>  		pgtbl_mod_mask *mask)
>  {
> @@ -217,7 +217,7 @@ static int vmap_pte_range(pmd_t *pmd, unsigned long addr,
>  	return 0;
>  }
>  
> -static int vmap_pmd_range(pud_t *pud, unsigned long addr,
> +static int vmap_pages_pmd_range(pud_t *pud, unsigned long addr,
>  		unsigned long end, pgprot_t prot, struct page **pages, int *nr,
>  		pgtbl_mod_mask *mask)
>  {
> @@ -229,13 +229,13 @@ static int vmap_pmd_range(pud_t *pud, unsigned long addr,
>  		return -ENOMEM;
>  	do {
>  		next = pmd_addr_end(addr, end);
> -		if (vmap_pte_range(pmd, addr, next, prot, pages, nr, mask))
> +		if (vmap_pages_pte_range(pmd, addr, next, prot, pages, nr, mask))
>  			return -ENOMEM;
>  	} while (pmd++, addr = next, addr != end);
>  	return 0;
>  }
>  
> -static int vmap_pud_range(p4d_t *p4d, unsigned long addr,
> +static int vmap_pages_pud_range(p4d_t *p4d, unsigned long addr,
>  		unsigned long end, pgprot_t prot, struct page **pages, int *nr,
>  		pgtbl_mod_mask *mask)
>  {
> @@ -247,13 +247,13 @@ static int vmap_pud_range(p4d_t *p4d, unsigned long addr,
>  		return -ENOMEM;
>  	do {
>  		next = pud_addr_end(addr, end);
> -		if (vmap_pmd_range(pud, addr, next, prot, pages, nr, mask))
> +		if (vmap_pages_pmd_range(pud, addr, next, prot, pages, nr, mask))
>  			return -ENOMEM;
>  	} while (pud++, addr = next, addr != end);
>  	return 0;
>  }
>  
> -static int vmap_p4d_range(pgd_t *pgd, unsigned long addr,
> +static int vmap_pages_p4d_range(pgd_t *pgd, unsigned long addr,
>  		unsigned long end, pgprot_t prot, struct page **pages, int *nr,
>  		pgtbl_mod_mask *mask)
>  {
> @@ -265,7 +265,7 @@ static int vmap_p4d_range(pgd_t *pgd, unsigned long addr,
>  		return -ENOMEM;
>  	do {
>  		next = p4d_addr_end(addr, end);
> -		if (vmap_pud_range(p4d, addr, next, prot, pages, nr, mask))
> +		if (vmap_pages_pud_range(p4d, addr, next, prot, pages, nr, mask))
>  			return -ENOMEM;
>  	} while (p4d++, addr = next, addr != end);
>  	return 0;
> @@ -306,7 +306,7 @@ int map_kernel_range_noflush(unsigned long addr, unsigned long size,
>  		next = pgd_addr_end(addr, end);
>  		if (pgd_bad(*pgd))
>  			mask |= PGTBL_PGD_MODIFIED;
> -		err = vmap_p4d_range(pgd, addr, next, prot, pages, &nr, &mask);
> +		err = vmap_pages_p4d_range(pgd, addr, next, prot, pages, &nr, &mask);
>  		if (err)
>  			return err;
>  	} while (pgd++, addr = next, addr != end);
> 

Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>

Re: [PATCH v11 05/13] mm: HUGE_VMAP arch support cleanup

[kernel test robot]

[-- Attachment #1: Type: text/plain, Size: 4050 bytes --]

Hi Nicholas,

I love your patch! Yet something to improve:

[auto build test ERROR on powerpc/next]
[also build test ERROR on arm64/for-next/core v5.11-rc5 next-20210125]
[cannot apply to hnaz-linux-mm/master]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Nicholas-Piggin/huge-vmalloc-mappings/20210126-143141
base:   https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git next
config: x86_64-allyesconfig (attached as .config)
compiler: gcc-9 (Debian 9.3.0-15) 9.3.0
reproduce (this is a W=1 build):
        # https://github.com/0day-ci/linux/commit/e43d3c665212ea34b790ab8d150bbde9d42e35b8
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Nicholas-Piggin/huge-vmalloc-mappings/20210126-143141
        git checkout e43d3c665212ea34b790ab8d150bbde9d42e35b8
        # save the attached .config to linux build tree
        make W=1 ARCH=x86_64 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All errors (new ones prefixed by >>):

   mm/debug_vm_pgtable.c: In function 'pmd_huge_tests':
   mm/debug_vm_pgtable.c:221:7: error: implicit declaration of function 'arch_ioremap_pmd_supported'; did you mean 'arch_vmap_pmd_supported'? [-Werror=implicit-function-declaration]
     221 |  if (!arch_ioremap_pmd_supported())
         |       ^~~~~~~~~~~~~~~~~~~~~~~~~~
         |       arch_vmap_pmd_supported
   mm/debug_vm_pgtable.c: In function 'pud_huge_tests':
>> mm/debug_vm_pgtable.c:343:7: error: implicit declaration of function 'arch_ioremap_pud_supported'; did you mean 'arch_vmap_pud_supported'? [-Werror=implicit-function-declaration]
     343 |  if (!arch_ioremap_pud_supported())
         |       ^~~~~~~~~~~~~~~~~~~~~~~~~~
         |       arch_vmap_pud_supported
   cc1: some warnings being treated as errors


vim +343 mm/debug_vm_pgtable.c

a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  337  
85a144632dcc71 Aneesh Kumar K.V  2020-10-15  338  #ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  339  static void __init pud_huge_tests(pud_t *pudp, unsigned long pfn, pgprot_t prot)
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  340  {
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  341  	pud_t pud;
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  342  
85a144632dcc71 Aneesh Kumar K.V  2020-10-15 @343  	if (!arch_ioremap_pud_supported())
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  344  		return;
6315df41afccf1 Anshuman Khandual 2020-08-06  345  
6315df41afccf1 Anshuman Khandual 2020-08-06  346  	pr_debug("Validating PUD huge\n");
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  347  	/*
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  348  	 * X86 defined pud_set_huge() verifies that the given
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  349  	 * PUD is not a populated non-leaf entry.
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  350  	 */
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  351  	WRITE_ONCE(*pudp, __pud(0));
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  352  	WARN_ON(!pud_set_huge(pudp, __pfn_to_phys(pfn), prot));
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  353  	WARN_ON(!pud_clear_huge(pudp));
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  354  	pud = READ_ONCE(*pudp);
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  355  	WARN_ON(!pud_none(pud));
a5c3b9ffb0f404 Anshuman Khandual 2020-08-06  356  }
85a144632dcc71 Aneesh Kumar K.V  2020-10-15  357  #else /* !CONFIG_HAVE_ARCH_HUGE_VMAP */
85a144632dcc71 Aneesh Kumar K.V  2020-10-15  358  static void __init pud_huge_tests(pud_t *pudp, unsigned long pfn, pgprot_t prot) { }
85a144632dcc71 Aneesh Kumar K.V  2020-10-15  359  #endif /* !CONFIG_HAVE_ARCH_HUGE_VMAP */
85a144632dcc71 Aneesh Kumar K.V  2020-10-15  360  

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org

[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 77785 bytes --]

Re: [PATCH v11 13/13] powerpc/64s/radix: Enable huge vmalloc mappings

[Michael Ellerman]

Nicholas Piggin <npiggin@gmail.com> writes:
> Cc: linuxppc-dev@lists.ozlabs.org
> Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
> ---

Acked-by: Michael Ellerman <mpe@ellerman.id.au>

cheers

>  .../admin-guide/kernel-parameters.txt         |  2 ++
>  arch/powerpc/Kconfig                          |  1 +
>  arch/powerpc/kernel/module.c                  | 21 +++++++++++++++----
>  3 files changed, 20 insertions(+), 4 deletions(-)
>
> diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
> index a10b545c2070..d62df53e5200 100644
> --- a/Documentation/admin-guide/kernel-parameters.txt
> +++ b/Documentation/admin-guide/kernel-parameters.txt
> @@ -3225,6 +3225,8 @@
>  
>  	nohugeiomap	[KNL,X86,PPC,ARM64] Disable kernel huge I/O mappings.
>  
> +	nohugevmalloc	[PPC] Disable kernel huge vmalloc mappings.
> +
>  	nosmt		[KNL,S390] Disable symmetric multithreading (SMT).
>  			Equivalent to smt=1.
>  
> diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
> index 107bb4319e0e..781da6829ab7 100644
> --- a/arch/powerpc/Kconfig
> +++ b/arch/powerpc/Kconfig
> @@ -181,6 +181,7 @@ config PPC
>  	select GENERIC_GETTIMEOFDAY
>  	select HAVE_ARCH_AUDITSYSCALL
>  	select HAVE_ARCH_HUGE_VMAP		if PPC_BOOK3S_64 && PPC_RADIX_MMU
> +	select HAVE_ARCH_HUGE_VMALLOC		if HAVE_ARCH_HUGE_VMAP
>  	select HAVE_ARCH_JUMP_LABEL
>  	select HAVE_ARCH_KASAN			if PPC32 && PPC_PAGE_SHIFT <= 14
>  	select HAVE_ARCH_KASAN_VMALLOC		if PPC32 && PPC_PAGE_SHIFT <= 14
> diff --git a/arch/powerpc/kernel/module.c b/arch/powerpc/kernel/module.c
> index a211b0253cdb..07026335d24d 100644
> --- a/arch/powerpc/kernel/module.c
> +++ b/arch/powerpc/kernel/module.c
> @@ -87,13 +87,26 @@ int module_finalize(const Elf_Ehdr *hdr,
>  	return 0;
>  }
>  
> -#ifdef MODULES_VADDR
>  void *module_alloc(unsigned long size)
>  {
> +	unsigned long start = VMALLOC_START;
> +	unsigned long end = VMALLOC_END;
> +
> +#ifdef MODULES_VADDR
>  	BUILD_BUG_ON(TASK_SIZE > MODULES_VADDR);
> +	start = MODULES_VADDR;
> +	end = MODULES_END;
> +#endif
> +
> +	/*
> +	 * Don't do huge page allocations for modules yet until more testing
> +	 * is done. STRICT_MODULE_RWX may require extra work to support this
> +	 * too.
> +	 */
>  
> -	return __vmalloc_node_range(size, 1, MODULES_VADDR, MODULES_END, GFP_KERNEL,
> -				    PAGE_KERNEL_EXEC, VM_FLUSH_RESET_PERMS, NUMA_NO_NODE,
> +	return __vmalloc_node_range(size, 1, start, end, GFP_KERNEL,
> +				    PAGE_KERNEL_EXEC,
> +				    VM_NO_HUGE_VMAP | VM_FLUSH_RESET_PERMS,
> +				    NUMA_NO_NODE,
>  				    __builtin_return_address(0));
>  }
> -#endif
> -- 
> 2.23.0

Re: [PATCH v11 04/13] mm/ioremap: rename ioremap_*_range to vmap_*_range

[Miaohe Lin]

Hi:
On 2021/1/26 12:45, Nicholas Piggin wrote:
> This will be used as a generic kernel virtual mapping function, so
> re-name it in preparation.
> 

Looks good to me. Thanks.

Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>

> Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
> ---
>  mm/ioremap.c | 64 +++++++++++++++++++++++++++-------------------------
>  1 file changed, 33 insertions(+), 31 deletions(-)
> 
> diff --git a/mm/ioremap.c b/mm/ioremap.c
> index 5fa1ab41d152..3f4d36f9745a 100644
> --- a/mm/ioremap.c
> +++ b/mm/ioremap.c
> @@ -61,9 +61,9 @@ static inline int ioremap_pud_enabled(void) { return 0; }
>  static inline int ioremap_pmd_enabled(void) { return 0; }
>  #endif	/* CONFIG_HAVE_ARCH_HUGE_VMAP */
>  
> -static int ioremap_pte_range(pmd_t *pmd, unsigned long addr,
> -		unsigned long end, phys_addr_t phys_addr, pgprot_t prot,
> -		pgtbl_mod_mask *mask)
> +static int vmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
> +			phys_addr_t phys_addr, pgprot_t prot,
> +			pgtbl_mod_mask *mask)
>  {
>  	pte_t *pte;
>  	u64 pfn;
> @@ -81,9 +81,8 @@ static int ioremap_pte_range(pmd_t *pmd, unsigned long addr,
>  	return 0;
>  }
>  
> -static int ioremap_try_huge_pmd(pmd_t *pmd, unsigned long addr,
> -				unsigned long end, phys_addr_t phys_addr,
> -				pgprot_t prot)
> +static int vmap_try_huge_pmd(pmd_t *pmd, unsigned long addr, unsigned long end,
> +			phys_addr_t phys_addr, pgprot_t prot)
>  {
>  	if (!ioremap_pmd_enabled())
>  		return 0;
> @@ -103,9 +102,9 @@ static int ioremap_try_huge_pmd(pmd_t *pmd, unsigned long addr,
>  	return pmd_set_huge(pmd, phys_addr, prot);
>  }
>  
> -static inline int ioremap_pmd_range(pud_t *pud, unsigned long addr,
> -		unsigned long end, phys_addr_t phys_addr, pgprot_t prot,
> -		pgtbl_mod_mask *mask)
> +static int vmap_pmd_range(pud_t *pud, unsigned long addr, unsigned long end,
> +			phys_addr_t phys_addr, pgprot_t prot,
> +			pgtbl_mod_mask *mask)
>  {
>  	pmd_t *pmd;
>  	unsigned long next;
> @@ -116,20 +115,19 @@ static inline int ioremap_pmd_range(pud_t *pud, unsigned long addr,
>  	do {
>  		next = pmd_addr_end(addr, end);
>  
> -		if (ioremap_try_huge_pmd(pmd, addr, next, phys_addr, prot)) {
> +		if (vmap_try_huge_pmd(pmd, addr, next, phys_addr, prot)) {
>  			*mask |= PGTBL_PMD_MODIFIED;
>  			continue;
>  		}
>  
> -		if (ioremap_pte_range(pmd, addr, next, phys_addr, prot, mask))
> +		if (vmap_pte_range(pmd, addr, next, phys_addr, prot, mask))
>  			return -ENOMEM;
>  	} while (pmd++, phys_addr += (next - addr), addr = next, addr != end);
>  	return 0;
>  }
>  
> -static int ioremap_try_huge_pud(pud_t *pud, unsigned long addr,
> -				unsigned long end, phys_addr_t phys_addr,
> -				pgprot_t prot)
> +static int vmap_try_huge_pud(pud_t *pud, unsigned long addr, unsigned long end,
> +			phys_addr_t phys_addr, pgprot_t prot)
>  {
>  	if (!ioremap_pud_enabled())
>  		return 0;
> @@ -149,9 +147,9 @@ static int ioremap_try_huge_pud(pud_t *pud, unsigned long addr,
>  	return pud_set_huge(pud, phys_addr, prot);
>  }
>  
> -static inline int ioremap_pud_range(p4d_t *p4d, unsigned long addr,
> -		unsigned long end, phys_addr_t phys_addr, pgprot_t prot,
> -		pgtbl_mod_mask *mask)
> +static int vmap_pud_range(p4d_t *p4d, unsigned long addr, unsigned long end,
> +			phys_addr_t phys_addr, pgprot_t prot,
> +			pgtbl_mod_mask *mask)
>  {
>  	pud_t *pud;
>  	unsigned long next;
> @@ -162,20 +160,19 @@ static inline int ioremap_pud_range(p4d_t *p4d, unsigned long addr,
>  	do {
>  		next = pud_addr_end(addr, end);
>  
> -		if (ioremap_try_huge_pud(pud, addr, next, phys_addr, prot)) {
> +		if (vmap_try_huge_pud(pud, addr, next, phys_addr, prot)) {
>  			*mask |= PGTBL_PUD_MODIFIED;
>  			continue;
>  		}
>  
> -		if (ioremap_pmd_range(pud, addr, next, phys_addr, prot, mask))
> +		if (vmap_pmd_range(pud, addr, next, phys_addr, prot, mask))
>  			return -ENOMEM;
>  	} while (pud++, phys_addr += (next - addr), addr = next, addr != end);
>  	return 0;
>  }
>  
> -static int ioremap_try_huge_p4d(p4d_t *p4d, unsigned long addr,
> -				unsigned long end, phys_addr_t phys_addr,
> -				pgprot_t prot)
> +static int vmap_try_huge_p4d(p4d_t *p4d, unsigned long addr, unsigned long end,
> +			phys_addr_t phys_addr, pgprot_t prot)
>  {
>  	if (!ioremap_p4d_enabled())
>  		return 0;
> @@ -195,9 +192,9 @@ static int ioremap_try_huge_p4d(p4d_t *p4d, unsigned long addr,
>  	return p4d_set_huge(p4d, phys_addr, prot);
>  }
>  
> -static inline int ioremap_p4d_range(pgd_t *pgd, unsigned long addr,
> -		unsigned long end, phys_addr_t phys_addr, pgprot_t prot,
> -		pgtbl_mod_mask *mask)
> +static int vmap_p4d_range(pgd_t *pgd, unsigned long addr, unsigned long end,
> +			phys_addr_t phys_addr, pgprot_t prot,
> +			pgtbl_mod_mask *mask)
>  {
>  	p4d_t *p4d;
>  	unsigned long next;
> @@ -208,19 +205,19 @@ static inline int ioremap_p4d_range(pgd_t *pgd, unsigned long addr,
>  	do {
>  		next = p4d_addr_end(addr, end);
>  
> -		if (ioremap_try_huge_p4d(p4d, addr, next, phys_addr, prot)) {
> +		if (vmap_try_huge_p4d(p4d, addr, next, phys_addr, prot)) {
>  			*mask |= PGTBL_P4D_MODIFIED;
>  			continue;
>  		}
>  
> -		if (ioremap_pud_range(p4d, addr, next, phys_addr, prot, mask))
> +		if (vmap_pud_range(p4d, addr, next, phys_addr, prot, mask))
>  			return -ENOMEM;
>  	} while (p4d++, phys_addr += (next - addr), addr = next, addr != end);
>  	return 0;
>  }
>  
> -int ioremap_page_range(unsigned long addr,
> -		       unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
> +static int vmap_range(unsigned long addr, unsigned long end,
> +			phys_addr_t phys_addr, pgprot_t prot)
>  {
>  	pgd_t *pgd;
>  	unsigned long start;
> @@ -235,8 +232,7 @@ int ioremap_page_range(unsigned long addr,
>  	pgd = pgd_offset_k(addr);
>  	do {
>  		next = pgd_addr_end(addr, end);
> -		err = ioremap_p4d_range(pgd, addr, next, phys_addr, prot,
> -					&mask);
> +		err = vmap_p4d_range(pgd, addr, next, phys_addr, prot, &mask);
>  		if (err)
>  			break;
>  	} while (pgd++, phys_addr += (next - addr), addr = next, addr != end);
> @@ -249,6 +245,12 @@ int ioremap_page_range(unsigned long addr,
>  	return err;
>  }
>  
> +int ioremap_page_range(unsigned long addr,
> +		       unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
> +{
> +	return vmap_range(addr, end, phys_addr, prot);
> +}
> +
>  #ifdef CONFIG_GENERIC_IOREMAP
>  void __iomem *ioremap_prot(phys_addr_t addr, size_t size, unsigned long prot)
>  {
> 

Re: [PATCH v11 01/13] mm/vmalloc: fix HUGE_VMAP regression by enabling huge pages in vmalloc_to_page

[Ding Tianhong]

On 2021/1/26 12:44, Nicholas Piggin wrote:
> vmalloc_to_page returns NULL for addresses mapped by larger pages[*].
> Whether or not a vmap is huge depends on the architecture details,
> alignments, boot options, etc., which the caller can not be expected
> to know. Therefore HUGE_VMAP is a regression for vmalloc_to_page.
> 
> This change teaches vmalloc_to_page about larger pages, and returns
> the struct page that corresponds to the offset within the large page.
> This makes the API agnostic to mapping implementation details.
> 
> [*] As explained by commit 029c54b095995 ("mm/vmalloc.c: huge-vmap:
>     fail gracefully on unexpected huge vmap mappings")
> 
> Reviewed-by: Christoph Hellwig <hch@lst.de>
> Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
> ---
>  mm/vmalloc.c | 41 ++++++++++++++++++++++++++---------------
>  1 file changed, 26 insertions(+), 15 deletions(-)
> 
> diff --git a/mm/vmalloc.c b/mm/vmalloc.c
> index e6f352bf0498..62372f9e0167 100644
> --- a/mm/vmalloc.c
> +++ b/mm/vmalloc.c
> @@ -34,7 +34,7 @@
>  #include <linux/bitops.h>
>  #include <linux/rbtree_augmented.h>
>  #include <linux/overflow.h>
> -
> +#include <linux/pgtable.h>
>  #include <linux/uaccess.h>
>  #include <asm/tlbflush.h>
>  #include <asm/shmparam.h>
> @@ -343,7 +343,9 @@ int is_vmalloc_or_module_addr(const void *x)
>  }
>  
>  /*
> - * Walk a vmap address to the struct page it maps.
> + * Walk a vmap address to the struct page it maps. Huge vmap mappings will
> + * return the tail page that corresponds to the base page address, which
> + * matches small vmap mappings.
>   */
>  struct page *vmalloc_to_page(const void *vmalloc_addr)
>  {
> @@ -363,25 +365,33 @@ struct page *vmalloc_to_page(const void *vmalloc_addr)
>  
>  	if (pgd_none(*pgd))
>  		return NULL;
> +	if (WARN_ON_ONCE(pgd_leaf(*pgd)))
> +		return NULL; /* XXX: no allowance for huge pgd */
> +	if (WARN_ON_ONCE(pgd_bad(*pgd)))
> +		return NULL;
> +
>  	p4d = p4d_offset(pgd, addr);
>  	if (p4d_none(*p4d))
>  		return NULL;
> -	pud = pud_offset(p4d, addr);
> +	if (p4d_leaf(*p4d))
> +		return p4d_page(*p4d) + ((addr & ~P4D_MASK) >> PAGE_SHIFT);
> +	if (WARN_ON_ONCE(p4d_bad(*p4d)))
> +		return NULL;
>  
> -	/*
> -	 * Don't dereference bad PUD or PMD (below) entries. This will also
> -	 * identify huge mappings, which we may encounter on architectures
> -	 * that define CONFIG_HAVE_ARCH_HUGE_VMAP=y. Such regions will be
> -	 * identified as vmalloc addresses by is_vmalloc_addr(), but are
> -	 * not [unambiguously] associated with a struct page, so there is
> -	 * no correct value to return for them.
> -	 */
> -	WARN_ON_ONCE(pud_bad(*pud));
> -	if (pud_none(*pud) || pud_bad(*pud))
> +	pud = pud_offset(p4d, addr);
> +	if (pud_none(*pud))
> +		return NULL;
> +	if (pud_leaf(*pud))
> +		return pud_page(*pud) + ((addr & ~PUD_MASK) >> PAGE_SHIFT);

Hi Nicho:

/builds/1mzfdQzleCy69KZFb5qHNSEgabZ/mm/vmalloc.c: In function 'vmalloc_to_page':
/builds/1mzfdQzleCy69KZFb5qHNSEgabZ/include/asm-generic/pgtable-nop4d-hack.h:48:27: error: implicit declaration of function 'pud_page'; did you mean 'put_page'? [-Werror=implicit-function-declaration]
   48 | #define pgd_page(pgd)    (pud_page((pud_t){ pgd }))
      |                           ^~~~~~~~

the pug_page is not defined for aarch32 when enabling 2-level page config, it break the system building.


> +	if (WARN_ON_ONCE(pud_bad(*pud)))
>  		return NULL;
> +
>  	pmd = pmd_offset(pud, addr);
> -	WARN_ON_ONCE(pmd_bad(*pmd));
> -	if (pmd_none(*pmd) || pmd_bad(*pmd))
> +	if (pmd_none(*pmd))
> +		return NULL;
> +	if (pmd_leaf(*pmd))
> +		return pmd_page(*pmd) + ((addr & ~PMD_MASK) >> PAGE_SHIFT);
> +	if (WARN_ON_ONCE(pmd_bad(*pmd)))
>  		return NULL;
>  
>  	ptep = pte_offset_map(pmd, addr);
> @@ -389,6 +399,7 @@ struct page *vmalloc_to_page(const void *vmalloc_addr)
>  	if (pte_present(pte))
>  		page = pte_page(pte);
>  	pte_unmap(ptep);
> +
>  	return page;
>  }
>  EXPORT_SYMBOL(vmalloc_to_page);
> 

Re: [PATCH v11 01/13] mm/vmalloc: fix HUGE_VMAP regression by enabling huge pages in vmalloc_to_page

[Nicholas Piggin]

Excerpts from Ding Tianhong's message of January 28, 2021 1:13 pm:
> On 2021/1/26 12:44, Nicholas Piggin wrote:
>> vmalloc_to_page returns NULL for addresses mapped by larger pages[*].
>> Whether or not a vmap is huge depends on the architecture details,
>> alignments, boot options, etc., which the caller can not be expected
>> to know. Therefore HUGE_VMAP is a regression for vmalloc_to_page.
>> 
>> This change teaches vmalloc_to_page about larger pages, and returns
>> the struct page that corresponds to the offset within the large page.
>> This makes the API agnostic to mapping implementation details.
>> 
>> [*] As explained by commit 029c54b095995 ("mm/vmalloc.c: huge-vmap:
>>     fail gracefully on unexpected huge vmap mappings")
>> 
>> Reviewed-by: Christoph Hellwig <hch@lst.de>
>> Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
>> ---
>>  mm/vmalloc.c | 41 ++++++++++++++++++++++++++---------------
>>  1 file changed, 26 insertions(+), 15 deletions(-)
>> 
>> diff --git a/mm/vmalloc.c b/mm/vmalloc.c
>> index e6f352bf0498..62372f9e0167 100644
>> --- a/mm/vmalloc.c
>> +++ b/mm/vmalloc.c
>> @@ -34,7 +34,7 @@
>>  #include <linux/bitops.h>
>>  #include <linux/rbtree_augmented.h>
>>  #include <linux/overflow.h>
>> -
>> +#include <linux/pgtable.h>
>>  #include <linux/uaccess.h>
>>  #include <asm/tlbflush.h>
>>  #include <asm/shmparam.h>
>> @@ -343,7 +343,9 @@ int is_vmalloc_or_module_addr(const void *x)
>>  }
>>  
>>  /*
>> - * Walk a vmap address to the struct page it maps.
>> + * Walk a vmap address to the struct page it maps. Huge vmap mappings will
>> + * return the tail page that corresponds to the base page address, which
>> + * matches small vmap mappings.
>>   */
>>  struct page *vmalloc_to_page(const void *vmalloc_addr)
>>  {
>> @@ -363,25 +365,33 @@ struct page *vmalloc_to_page(const void *vmalloc_addr)
>>  
>>  	if (pgd_none(*pgd))
>>  		return NULL;
>> +	if (WARN_ON_ONCE(pgd_leaf(*pgd)))
>> +		return NULL; /* XXX: no allowance for huge pgd */
>> +	if (WARN_ON_ONCE(pgd_bad(*pgd)))
>> +		return NULL;
>> +
>>  	p4d = p4d_offset(pgd, addr);
>>  	if (p4d_none(*p4d))
>>  		return NULL;
>> -	pud = pud_offset(p4d, addr);
>> +	if (p4d_leaf(*p4d))
>> +		return p4d_page(*p4d) + ((addr & ~P4D_MASK) >> PAGE_SHIFT);
>> +	if (WARN_ON_ONCE(p4d_bad(*p4d)))
>> +		return NULL;
>>  
>> -	/*
>> -	 * Don't dereference bad PUD or PMD (below) entries. This will also
>> -	 * identify huge mappings, which we may encounter on architectures
>> -	 * that define CONFIG_HAVE_ARCH_HUGE_VMAP=y. Such regions will be
>> -	 * identified as vmalloc addresses by is_vmalloc_addr(), but are
>> -	 * not [unambiguously] associated with a struct page, so there is
>> -	 * no correct value to return for them.
>> -	 */
>> -	WARN_ON_ONCE(pud_bad(*pud));
>> -	if (pud_none(*pud) || pud_bad(*pud))
>> +	pud = pud_offset(p4d, addr);
>> +	if (pud_none(*pud))
>> +		return NULL;
>> +	if (pud_leaf(*pud))
>> +		return pud_page(*pud) + ((addr & ~PUD_MASK) >> PAGE_SHIFT);
> 
> Hi Nicho:
> 
> /builds/1mzfdQzleCy69KZFb5qHNSEgabZ/mm/vmalloc.c: In function 'vmalloc_to_page':
> /builds/1mzfdQzleCy69KZFb5qHNSEgabZ/include/asm-generic/pgtable-nop4d-hack.h:48:27: error: implicit declaration of function 'pud_page'; did you mean 'put_page'? [-Werror=implicit-function-declaration]
>    48 | #define pgd_page(pgd)    (pud_page((pud_t){ pgd }))
>       |                           ^~~~~~~~
> 
> the pug_page is not defined for aarch32 when enabling 2-level page config, it break the system building.

Hey thanks for finding that, not sure why that didn't trigger any CI.

Anyway newer kernels don't have the ptable-*-hack.h headers, but even so 
it still breaks upstream. arm is using some hand-rolled 2-level folding
of its own (which is fair enough because most 32-bit archs were 2 level
at the time I added pgtable-nopud.h header).

This patch seems to at least make it build.

Thanks,
Nick

---
 arch/arm/include/asm/pgtable-3level.h | 2 --
 arch/arm/include/asm/pgtable.h        | 3 +++
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/arch/arm/include/asm/pgtable-3level.h b/arch/arm/include/asm/pgtable-3level.h
index 2b85d175e999..d4edab51a77c 100644
--- a/arch/arm/include/asm/pgtable-3level.h
+++ b/arch/arm/include/asm/pgtable-3level.h
@@ -186,8 +186,6 @@ static inline pte_t pte_mkspecial(pte_t pte)
 
 #define pmd_write(pmd)		(pmd_isclear((pmd), L_PMD_SECT_RDONLY))
 #define pmd_dirty(pmd)		(pmd_isset((pmd), L_PMD_SECT_DIRTY))
-#define pud_page(pud)		pmd_page(__pmd(pud_val(pud)))
-#define pud_write(pud)		pmd_write(__pmd(pud_val(pud)))
 
 #define pmd_hugewillfault(pmd)	(!pmd_young(pmd) || !pmd_write(pmd))
 #define pmd_thp_or_huge(pmd)	(pmd_huge(pmd) || pmd_trans_huge(pmd))
diff --git a/arch/arm/include/asm/pgtable.h b/arch/arm/include/asm/pgtable.h
index c02f24400369..d63a5bb6bd0c 100644
--- a/arch/arm/include/asm/pgtable.h
+++ b/arch/arm/include/asm/pgtable.h
@@ -166,6 +166,9 @@ extern struct page *empty_zero_page;
 
 extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
 
+#define pud_page(pud)		pmd_page(__pmd(pud_val(pud)))
+#define pud_write(pud)		pmd_write(__pmd(pud_val(pud)))
+
 #define pmd_none(pmd)		(!pmd_val(pmd))
 
 static inline pte_t *pmd_page_vaddr(pmd_t pmd)
-- 
2.23.0