From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A69BF2727EB for ; Sun, 5 Jul 2026 20:36:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783283791; cv=none; b=fJSXQp55rc6PUoJTRU4OKlVf8pOWqI0HNoy5yzke0BX8O1puLbIVGVO3rmBY3Uj5VSNtOEiJWFW0X0cZPKAKVfYNTZg0ld9r/eUQB5Q8/NShdhjl3bNzSZLDl0Pqd3MwRJxqi7grVDG04CDKA4lZt5BTGL1itJHTTZ6EM3XWPX8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783283791; c=relaxed/simple; bh=I/SxdG53S7HNDK4jsgG8X0DYW/yePgKveVz5oDBv7SU=; h=Date:To:From:Subject:Message-Id; b=bMUkksqrvxQgUuuiA8b8/NeSxDeEjMwY13QEzPYQUePaS756wBqzyZZAR4DHYPhmA25VAlniahV14pLZlkm3cGSvsLQT1RF1j7Mj3bgNUSnMMDSfjstJ0AZQKGr3Fha5w5X0acXf/589dibnzU+COgVzx1H5i+8Hdd4YY8aOxlQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=2msiCF69; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="2msiCF69" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 63CA01F00A3A; Sun, 5 Jul 2026 20:36:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=korg; t=1783283789; bh=eqS+s9GiTWcX7A26Rjaeq5ZQHii5SsDOVungXqfxKVo=; h=Date:To:From:Subject; b=2msiCF69BF8ErjwW6c6zucjC3tx3QuRb+fek3ia/A2eRo5BfzkuGGHm0TVDk3CEoG 6EQk1sF09R390cmtXbWR+EMIRUx4VMg45Ava7naSglvMcgq1Fy55W4R89l/Q1VVS9M sLRV9dbKl68ubG0K551Yqydmh3SjlBupAf0GeuV8= Date: Sun, 05 Jul 2026 13:36:29 -0700 To: mm-commits@vger.kernel.org,baohua@kernel.org,akpm@linux-foundation.org From: Andrew Morton Subject: [to-be-updated] mm-vmalloc-extend-page-table-walk-to-support-larger-page_shift-sizes-and-eliminate-page-table-rewalk.patch removed from -mm tree Message-Id: <20260705203629.63CA01F00A3A@smtp.kernel.org> Precedence: bulk X-Mailing-List: mm-commits@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The quilt patch titled Subject: mm/vmalloc: extend page table walk to support larger page_shift sizes and eliminate page table rewalk has been removed from the -mm tree. Its filename was mm-vmalloc-extend-page-table-walk-to-support-larger-page_shift-sizes-and-eliminate-page-table-rewalk.patch This patch was dropped because an updated version will be issued ------------------------------------------------------ From: "Barry Song (Xiaomi)" Subject: mm/vmalloc: extend page table walk to support larger page_shift sizes and eliminate page table rewalk Date: Thu, 18 Jun 2026 16:47:24 +0800 vmap_pages_range_noflush_walk() (formerly vmap_small_pages_range_noflush()) provides a clean interface by taking struct page **pages and mapping them via direct PTE iteration. This avoids the page table rewalk seen when using vmap_range_noflush() for page_shift values other than PAGE_SHIFT. Extend it to support larger page_shift values, and add PMD- and contiguous-PTE mappings as well. Rename it to vmap_pages_range_noflush_walk() since it now handles more than just small pages. For vmalloc() allocations with VM_ALLOW_HUGE_VMAP, we no longer need to iterate over pages one by one via vmap_range_noflush(), which would otherwise lead to page table rewalk. The code is now unified with the PAGE_SHIFT case by simply calling vmap_pages_range_noflush_walk(). Link: https://lore.kernel.org/20260618084726.1070022-5-jiangwen6@xiaomi.com Signed-off-by: Barry Song (Xiaomi) Signed-off-by: Wen Jiang Tested-by: Xueyuan Chen Tested-by: Leo Yan Reviewed-by: Dev Jain Cc: Andrew Donnellan Cc: Anshuman Khandual Cc: Catalin Marinas Cc: David Hildenbrand Cc: Mike Rapoport Cc: Ryan Roberts Cc: Uladzislau Rezki Cc: Wen Jiang Cc: Will Deacon Signed-off-by: Andrew Morton --- mm/vmalloc.c | 81 ++++++++++++++++++++++++++++--------------------- 1 file changed, 47 insertions(+), 34 deletions(-) --- a/mm/vmalloc.c~mm-vmalloc-extend-page-table-walk-to-support-larger-page_shift-sizes-and-eliminate-page-table-rewalk +++ a/mm/vmalloc.c @@ -127,7 +127,8 @@ static int vmap_pte_range(pmd_t *pmd, un pte_t *pte; u64 pfn; struct page *page; - unsigned long size = PAGE_SIZE; + unsigned long size; + unsigned int steps; if (WARN_ON_ONCE(!PAGE_ALIGNED(end - addr))) return -EINVAL; @@ -149,8 +150,8 @@ static int vmap_pte_range(pmd_t *pmd, un } size = vmap_set_ptes(pte, addr, end, pfn, prot, max_page_shift); - pfn += PFN_DOWN(size); - } while (pte += PFN_DOWN(size), addr += size, addr != end); + steps = PFN_DOWN(size); + } while (pte += steps, pfn += steps, addr += size, addr != end); lazy_mmu_mode_disable(); *mask |= PGTBL_PTE_MODIFIED; @@ -542,8 +543,10 @@ void vunmap_range(unsigned long addr, un 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) + pgtbl_mod_mask *mask, unsigned int shift) { + unsigned long pfn, size; + unsigned int steps; int err = 0; pte_t *pte; @@ -574,9 +577,10 @@ static int vmap_pages_pte_range(pmd_t *p break; } - set_pte_at(&init_mm, addr, pte, mk_pte(page, prot)); - (*nr)++; - } while (pte++, addr += PAGE_SIZE, addr != end); + pfn = page_to_pfn(page); + size = vmap_set_ptes(pte, addr, end, pfn, prot, shift); + steps = PFN_DOWN(size); + } while (pte += steps, *nr += steps, addr += size, addr != end); lazy_mmu_mode_disable(); *mask |= PGTBL_PTE_MODIFIED; @@ -586,7 +590,7 @@ static int vmap_pages_pte_range(pmd_t *p 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) + pgtbl_mod_mask *mask, unsigned int shift) { pmd_t *pmd; unsigned long next; @@ -596,7 +600,27 @@ static int vmap_pages_pmd_range(pud_t *p return -ENOMEM; do { next = pmd_addr_end(addr, end); - if (vmap_pages_pte_range(pmd, addr, next, prot, pages, nr, mask)) + + if (shift >= PMD_SHIFT) { + struct page *page = pages[*nr]; + phys_addr_t phys_addr; + + if (WARN_ON(!page)) + return -ENOMEM; + if (WARN_ON(!pfn_valid(page_to_pfn(page)))) + return -EINVAL; + + phys_addr = page_to_phys(page); + + if (vmap_try_huge_pmd(pmd, addr, next, phys_addr, prot, + shift)) { + *mask |= PGTBL_PMD_MODIFIED; + *nr += 1 << (PMD_SHIFT - PAGE_SHIFT); + continue; + } + } + + if (vmap_pages_pte_range(pmd, addr, next, prot, pages, nr, mask, shift)) return -ENOMEM; } while (pmd++, addr = next, addr != end); return 0; @@ -604,7 +628,7 @@ static int vmap_pages_pmd_range(pud_t *p 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) + pgtbl_mod_mask *mask, unsigned int shift) { pud_t *pud; unsigned long next; @@ -614,7 +638,7 @@ static int vmap_pages_pud_range(p4d_t *p return -ENOMEM; do { next = pud_addr_end(addr, end); - if (vmap_pages_pmd_range(pud, addr, next, prot, pages, nr, mask)) + if (vmap_pages_pmd_range(pud, addr, next, prot, pages, nr, mask, shift)) return -ENOMEM; } while (pud++, addr = next, addr != end); return 0; @@ -622,7 +646,7 @@ static int vmap_pages_pud_range(p4d_t *p 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) + pgtbl_mod_mask *mask, unsigned int shift) { p4d_t *p4d; unsigned long next; @@ -632,14 +656,18 @@ static int vmap_pages_p4d_range(pgd_t *p return -ENOMEM; do { next = p4d_addr_end(addr, end); - if (vmap_pages_pud_range(p4d, addr, next, prot, pages, nr, mask)) + if (vmap_pages_pud_range(p4d, addr, next, prot, pages, nr, mask, shift)) return -ENOMEM; } while (p4d++, addr = next, addr != end); return 0; } -static int vmap_small_pages_range_noflush(unsigned long addr, unsigned long end, - pgprot_t prot, struct page **pages) +/* + * It can take an array of pages which are not all contiguous, but it + * may have contiguous chunks, as hinted by @shift. + */ +static int vmap_pages_range_noflush_walk(unsigned long addr, unsigned long end, + pgprot_t prot, struct page **pages, unsigned int shift) { unsigned long start = addr; pgd_t *pgd; @@ -654,7 +682,7 @@ static int vmap_small_pages_range_noflus next = pgd_addr_end(addr, end); if (pgd_bad(*pgd)) mask |= PGTBL_PGD_MODIFIED; - err = vmap_pages_p4d_range(pgd, addr, next, prot, pages, &nr, &mask); + err = vmap_pages_p4d_range(pgd, addr, next, prot, pages, &nr, &mask, shift); if (err) break; } while (pgd++, addr = next, addr != end); @@ -677,27 +705,12 @@ static int vmap_small_pages_range_noflus 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), - page_to_phys(pages[i]), prot, - page_shift); - if (err) - return err; - - addr += 1UL << page_shift; - } + if (!IS_ENABLED(CONFIG_HAVE_ARCH_HUGE_VMALLOC)) + page_shift = PAGE_SHIFT; - return 0; + return vmap_pages_range_noflush_walk(addr, end, prot, pages, page_shift); } int vmap_pages_range_noflush(unsigned long addr, unsigned long end, _ Patches currently in -mm which might be from baohua@kernel.org are mm-vmalloc-map-contiguous-pages-in-batches-for-vmap-if-possible.patch mm-vmalloc-align-vm_area-so-vmap-can-batch-mappings.patch