The patch titled
Subject: mm: remove CONFIG_ARCH_HAS_HUGEPD
has been added to the -mm mm-unstable branch. Its filename is
mm-remove-config_arch_has_hugepd.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-remove-config_arch_has_hugepd.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next via the mm-everything
branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there every 2-3 working days
------------------------------------------------------
From: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
Subject: mm: remove CONFIG_ARCH_HAS_HUGEPD
Date: Tue, 2 Jul 2024 15:51:35 +0200
powerpc was the only user of CONFIG_ARCH_HAS_HUGEPD and doesn't use it
anymore, so remove all related code.
Link: https://lkml.kernel.org/r/4b10c54c794780b955f3ad6c657d0199dd792146.1719928057.git.christophe.leroy@xxxxxxxxxx
Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
Acked-by: Oscar Salvador <osalvador@xxxxxxx>
Cc: Jason Gunthorpe <jgg@xxxxxxxxxx>
Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Cc: Nicholas Piggin <npiggin@xxxxxxxxx>
Cc: Peter Xu <peterx@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/hugetlb.h | 6 -
mm/Kconfig | 10 -
mm/gup.c | 194 --------------------------------------
mm/pagewalk.c | 57 -----------
4 files changed, 9 insertions(+), 258 deletions(-)
--- a/include/linux/hugetlb.h~mm-remove-config_arch_has_hugepd
+++ a/include/linux/hugetlb.h
@@ -20,12 +20,6 @@ struct user_struct;
struct mmu_gather;
struct node;
-#ifndef CONFIG_ARCH_HAS_HUGEPD
-typedef struct { unsigned long pd; } hugepd_t;
-#define is_hugepd(hugepd) (0)
-#define __hugepd(x) ((hugepd_t) { (x) })
-#endif
-
void free_huge_folio(struct folio *folio);
#ifdef CONFIG_HUGETLB_PAGE
--- a/mm/gup.c~mm-remove-config_arch_has_hugepd
+++ a/mm/gup.c
@@ -462,7 +462,7 @@ static inline void mm_set_has_pinned_fla
#ifdef CONFIG_MMU
-#if defined(CONFIG_ARCH_HAS_HUGEPD) || defined(CONFIG_HAVE_GUP_FAST)
+#ifdef CONFIG_HAVE_GUP_FAST
static int record_subpages(struct page *page, unsigned long sz,
unsigned long addr, unsigned long end,
struct page **pages)
@@ -572,154 +572,7 @@ static struct folio *try_grab_folio_fast
return folio;
}
-#endif /* CONFIG_ARCH_HAS_HUGEPD || CONFIG_HAVE_GUP_FAST */
-
-#ifdef CONFIG_ARCH_HAS_HUGEPD
-static unsigned long hugepte_addr_end(unsigned long addr, unsigned long end,
- unsigned long sz)
-{
- unsigned long __boundary = (addr + sz) & ~(sz-1);
- return (__boundary - 1 < end - 1) ? __boundary : end;
-}
-
-/*
- * Returns 1 if succeeded, 0 if failed, -EMLINK if unshare needed.
- *
- * NOTE: for the same entry, gup-fast and gup-slow can return different
- * results (0 v.s. -EMLINK) depending on whether vma is available. This is
- * the expected behavior, where we simply want gup-fast to fallback to
- * gup-slow to take the vma reference first.
- */
-static int gup_hugepte(struct vm_area_struct *vma, pte_t *ptep, unsigned long sz,
- unsigned long addr, unsigned long end, unsigned int flags,
- struct page **pages, int *nr, bool fast)
-{
- unsigned long pte_end;
- struct page *page;
- struct folio *folio;
- pte_t pte;
- int refs;
-
- pte_end = (addr + sz) & ~(sz-1);
- if (pte_end < end)
- end = pte_end;
-
- pte = huge_ptep_get(vma->vm_mm, addr, ptep);
-
- if (!pte_access_permitted(pte, flags & FOLL_WRITE))
- return 0;
-
- /* hugepages are never "special" */
- VM_BUG_ON(!pfn_valid(pte_pfn(pte)));
-
- page = pte_page(pte);
- refs = record_subpages(page, sz, addr, end, pages + *nr);
-
- if (fast) {
- folio = try_grab_folio_fast(page, refs, flags);
- if (!folio)
- return 0;
- } else {
- folio = page_folio(page);
- if (try_grab_folio(folio, refs, flags))
- return 0;
- }
-
- if (unlikely(pte_val(pte) != pte_val(ptep_get(ptep)))) {
- gup_put_folio(folio, refs, flags);
- return 0;
- }
-
- if (!pte_write(pte) && gup_must_unshare(vma, flags, &folio->page)) {
- gup_put_folio(folio, refs, flags);
- return -EMLINK;
- }
-
- *nr += refs;
- folio_set_referenced(folio);
- return 1;
-}
-
-/*
- * NOTE: currently GUP for a hugepd is only possible on hugetlbfs file
- * systems on Power, which does not have issue with folio writeback against
- * GUP updates. When hugepd will be extended to support non-hugetlbfs or
- * even anonymous memory, we need to do extra check as what we do with most
- * of the other folios. See writable_file_mapping_allowed() and
- * gup_fast_folio_allowed() for more information.
- */
-static int gup_hugepd(struct vm_area_struct *vma, hugepd_t hugepd,
- unsigned long addr, unsigned int pdshift,
- unsigned long end, unsigned int flags,
- struct page **pages, int *nr, bool fast)
-{
- pte_t *ptep;
- unsigned long sz = 1UL << hugepd_shift(hugepd);
- unsigned long next;
- int ret;
-
- ptep = hugepte_offset(hugepd, addr, pdshift);
- do {
- next = hugepte_addr_end(addr, end, sz);
- ret = gup_hugepte(vma, ptep, sz, addr, end, flags, pages, nr,
- fast);
- if (ret != 1)
- return ret;
- } while (ptep++, addr = next, addr != end);
-
- return 1;
-}
-
-static struct page *follow_hugepd(struct vm_area_struct *vma, hugepd_t hugepd,
- unsigned long addr, unsigned int pdshift,
- unsigned int flags,
- struct follow_page_context *ctx)
-{
- struct page *page;
- struct hstate *h;
- spinlock_t *ptl;
- int nr = 0, ret;
- pte_t *ptep;
-
- /* Only hugetlb supports hugepd */
- if (WARN_ON_ONCE(!is_vm_hugetlb_page(vma)))
- return ERR_PTR(-EFAULT);
-
- h = hstate_vma(vma);
- ptep = hugepte_offset(hugepd, addr, pdshift);
- ptl = huge_pte_lock(h, vma->vm_mm, ptep);
- ret = gup_hugepd(vma, hugepd, addr, pdshift, addr + PAGE_SIZE,
- flags, &page, &nr, false);
- spin_unlock(ptl);
-
- if (ret == 1) {
- /* GUP succeeded */
- WARN_ON_ONCE(nr != 1);
- ctx->page_mask = (1U << huge_page_order(h)) - 1;
- return page;
- }
-
- /* ret can be either 0 (translates to NULL) or negative */
- return ERR_PTR(ret);
-}
-#else /* CONFIG_ARCH_HAS_HUGEPD */
-static inline int gup_hugepd(struct vm_area_struct *vma, hugepd_t hugepd,
- unsigned long addr, unsigned int pdshift,
- unsigned long end, unsigned int flags,
- struct page **pages, int *nr, bool fast)
-{
- return 0;
-}
-
-static struct page *follow_hugepd(struct vm_area_struct *vma, hugepd_t hugepd,
- unsigned long addr, unsigned int pdshift,
- unsigned int flags,
- struct follow_page_context *ctx)
-{
- return NULL;
-}
-#endif /* CONFIG_ARCH_HAS_HUGEPD */
-
+#endif /* CONFIG_HAVE_GUP_FAST */
static struct page *no_page_table(struct vm_area_struct *vma,
unsigned int flags, unsigned long address)
@@ -1089,9 +942,6 @@ static struct page *follow_pmd_mask(stru
return no_page_table(vma, flags, address);
if (!pmd_present(pmdval))
return no_page_table(vma, flags, address);
- if (unlikely(is_hugepd(__hugepd(pmd_val(pmdval)))))
- return follow_hugepd(vma, __hugepd(pmd_val(pmdval)),
- address, PMD_SHIFT, flags, ctx);
if (pmd_devmap(pmdval)) {
ptl = pmd_lock(mm, pmd);
page = follow_devmap_pmd(vma, address, pmd, flags, &ctx->pgmap);
@@ -1142,9 +992,6 @@ static struct page *follow_pud_mask(stru
pud = READ_ONCE(*pudp);
if (!pud_present(pud))
return no_page_table(vma, flags, address);
- if (unlikely(is_hugepd(__hugepd(pud_val(pud)))))
- return follow_hugepd(vma, __hugepd(pud_val(pud)),
- address, PUD_SHIFT, flags, ctx);
if (pud_leaf(pud)) {
ptl = pud_lock(mm, pudp);
page = follow_huge_pud(vma, address, pudp, flags, ctx);
@@ -1170,10 +1017,6 @@ static struct page *follow_p4d_mask(stru
p4d = READ_ONCE(*p4dp);
BUILD_BUG_ON(p4d_leaf(p4d));
- if (unlikely(is_hugepd(__hugepd(p4d_val(p4d)))))
- return follow_hugepd(vma, __hugepd(p4d_val(p4d)),
- address, P4D_SHIFT, flags, ctx);
-
if (!p4d_present(p4d) || p4d_bad(p4d))
return no_page_table(vma, flags, address);
@@ -1217,10 +1060,7 @@ static struct page *follow_page_mask(str
ctx->page_mask = 0;
pgd = pgd_offset(mm, address);
- if (unlikely(is_hugepd(__hugepd(pgd_val(*pgd)))))
- page = follow_hugepd(vma, __hugepd(pgd_val(*pgd)),
- address, PGDIR_SHIFT, flags, ctx);
- else if (pgd_none(*pgd) || unlikely(pgd_bad(*pgd)))
+ if (pgd_none(*pgd) || unlikely(pgd_bad(*pgd)))
page = no_page_table(vma, flags, address);
else
page = follow_p4d_mask(vma, address, pgd, flags, ctx);
@@ -3362,15 +3202,6 @@ static int gup_fast_pmd_range(pud_t *pud
pages, nr))
return 0;
- } else if (unlikely(is_hugepd(__hugepd(pmd_val(pmd))))) {
- /*
- * architecture have different format for hugetlbfs
- * pmd format and THP pmd format
- */
- if (gup_hugepd(NULL, __hugepd(pmd_val(pmd)), addr,
- PMD_SHIFT, next, flags, pages, nr,
- true) != 1)
- return 0;
} else if (!gup_fast_pte_range(pmd, pmdp, addr, next, flags,
pages, nr))
return 0;
@@ -3397,11 +3228,6 @@ static int gup_fast_pud_range(p4d_t *p4d
if (!gup_fast_pud_leaf(pud, pudp, addr, next, flags,
pages, nr))
return 0;
- } else if (unlikely(is_hugepd(__hugepd(pud_val(pud))))) {
- if (gup_hugepd(NULL, __hugepd(pud_val(pud)), addr,
- PUD_SHIFT, next, flags, pages, nr,
- true) != 1)
- return 0;
} else if (!gup_fast_pmd_range(pudp, pud, addr, next, flags,
pages, nr))
return 0;
@@ -3425,13 +3251,8 @@ static int gup_fast_p4d_range(pgd_t *pgd
if (!p4d_present(p4d))
return 0;
BUILD_BUG_ON(p4d_leaf(p4d));
- if (unlikely(is_hugepd(__hugepd(p4d_val(p4d))))) {
- if (gup_hugepd(NULL, __hugepd(p4d_val(p4d)), addr,
- P4D_SHIFT, next, flags, pages, nr,
- true) != 1)
- return 0;
- } else if (!gup_fast_pud_range(p4dp, p4d, addr, next, flags,
- pages, nr))
+ if (!gup_fast_pud_range(p4dp, p4d, addr, next, flags,
+ pages, nr))
return 0;
} while (p4dp++, addr = next, addr != end);
@@ -3455,11 +3276,6 @@ static void gup_fast_pgd_range(unsigned
if (!gup_fast_pgd_leaf(pgd, pgdp, addr, next, flags,
pages, nr))
return;
- } else if (unlikely(is_hugepd(__hugepd(pgd_val(pgd))))) {
- if (gup_hugepd(NULL, __hugepd(pgd_val(pgd)), addr,
- PGDIR_SHIFT, next, flags, pages, nr,
- true) != 1)
- return;
} else if (!gup_fast_p4d_range(pgdp, pgd, addr, next, flags,
pages, nr))
return;
--- a/mm/Kconfig~mm-remove-config_arch_has_hugepd
+++ a/mm/Kconfig
@@ -1126,16 +1126,6 @@ config DMAPOOL_TEST
config ARCH_HAS_PTE_SPECIAL
bool
-#
-# Some architectures require a special hugepage directory format that is
-# required to support multiple hugepage sizes. For example a4fe3ce76
-# "powerpc/mm: Allow more flexible layouts for hugepage pagetables"
-# introduced it on powerpc. This allows for a more flexible hugepage
-# pagetable layouts.
-#
-config ARCH_HAS_HUGEPD
- bool
-
config MAPPING_DIRTY_HELPERS
bool
--- a/mm/pagewalk.c~mm-remove-config_arch_has_hugepd
+++ a/mm/pagewalk.c
@@ -73,45 +73,6 @@ static int walk_pte_range(pmd_t *pmd, un
return err;
}
-#ifdef CONFIG_ARCH_HAS_HUGEPD
-static int walk_hugepd_range(hugepd_t *phpd, unsigned long addr,
- unsigned long end, struct mm_walk *walk, int pdshift)
-{
- int err = 0;
- const struct mm_walk_ops *ops = walk->ops;
- int shift = hugepd_shift(*phpd);
- int page_size = 1 << shift;
-
- if (!ops->pte_entry)
- return 0;
-
- if (addr & (page_size - 1))
- return 0;
-
- for (;;) {
- pte_t *pte;
-
- spin_lock(&walk->mm->page_table_lock);
- pte = hugepte_offset(*phpd, addr, pdshift);
- err = ops->pte_entry(pte, addr, addr + page_size, walk);
- spin_unlock(&walk->mm->page_table_lock);
-
- if (err)
- break;
- if (addr >= end - page_size)
- break;
- addr += page_size;
- }
- return err;
-}
-#else
-static int walk_hugepd_range(hugepd_t *phpd, unsigned long addr,
- unsigned long end, struct mm_walk *walk, int pdshift)
-{
- return 0;
-}
-#endif
-
static int walk_pmd_range(pud_t *pud, unsigned long addr, unsigned long end,
struct mm_walk *walk)
{
@@ -159,10 +120,7 @@ again:
if (walk->vma)
split_huge_pmd(walk->vma, pmd, addr);
- if (is_hugepd(__hugepd(pmd_val(*pmd))))
- err = walk_hugepd_range((hugepd_t *)pmd, addr, next, walk, PMD_SHIFT);
- else
- err = walk_pte_range(pmd, addr, next, walk);
+ err = walk_pte_range(pmd, addr, next, walk);
if (err)
break;
@@ -215,10 +173,7 @@ static int walk_pud_range(p4d_t *p4d, un
if (pud_none(*pud))
goto again;
- if (is_hugepd(__hugepd(pud_val(*pud))))
- err = walk_hugepd_range((hugepd_t *)pud, addr, next, walk, PUD_SHIFT);
- else
- err = walk_pmd_range(pud, addr, next, walk);
+ err = walk_pmd_range(pud, addr, next, walk);
if (err)
break;
} while (pud++, addr = next, addr != end);
@@ -250,9 +205,7 @@ static int walk_p4d_range(pgd_t *pgd, un
if (err)
break;
}
- if (is_hugepd(__hugepd(p4d_val(*p4d))))
- err = walk_hugepd_range((hugepd_t *)p4d, addr, next, walk, P4D_SHIFT);
- else if (ops->pud_entry || ops->pmd_entry || ops->pte_entry)
+ if (ops->pud_entry || ops->pmd_entry || ops->pte_entry)
err = walk_pud_range(p4d, addr, next, walk);
if (err)
break;
@@ -287,9 +240,7 @@ static int walk_pgd_range(unsigned long
if (err)
break;
}
- if (is_hugepd(__hugepd(pgd_val(*pgd))))
- err = walk_hugepd_range((hugepd_t *)pgd, addr, next, walk, PGDIR_SHIFT);
- else if (ops->p4d_entry || ops->pud_entry || ops->pmd_entry || ops->pte_entry)
+ if (ops->p4d_entry || ops->pud_entry || ops->pmd_entry || ops->pte_entry)
err = walk_p4d_range(pgd, addr, next, walk);
if (err)
break;
_
Patches currently in -mm which might be from christophe.leroy@xxxxxxxxxx are
mm-define-__pte_leaf_size-to-also-take-a-pmd-entry.patch
mm-provide-mm_struct-and-address-to-huge_ptep_get.patch
powerpc-mm-remove-_page_psize.patch
powerpc-mm-fix-__find_linux_pte-on-32-bits-with-pmd-leaf-entries.patch
powerpc-mm-allow-hugepages-without-hugepd.patch
powerpc-8xx-fix-size-given-to-set_huge_pte_at.patch
powerpc-8xx-rework-support-for-8m-pages-using-contiguous-pte-entries.patch
powerpc-8xx-simplify-struct-mmu_psize_def.patch
powerpc-e500-remove-enc-and-ind-fields-from-struct-mmu_psize_def.patch
powerpc-e500-switch-to-64-bits-pgd-on-85xx-32-bits.patch
powerpc-e500-encode-hugepage-size-in-pte-bits.patch
powerpc-e500-dont-pre-check-write-access-on-data-tlb-error.patch
powerpc-e500-free-r10-for-find_pte.patch
powerpc-e500-use-contiguous-pmd-instead-of-hugepd.patch
powerpc-64s-use-contiguous-pmd-pud-instead-of-hugepd.patch
powerpc-mm-remove-hugepd-leftovers.patch
mm-remove-config_arch_has_hugepd.patch
