linux-kernel - [PATCH 27/45] mm/damon: Create damon_young_pud

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20240704043132.28501-28-osalvador@suse.de>
Date: Thu,  4 Jul 2024 06:31:14 +0200
From: Oscar Salvador <osalvador@...e.de>
To: Andrew Morton <akpm@...ux-foundation.org>
Cc: linux-kernel@...r.kernel.org,
	linux-mm@...ck.org,
	Peter Xu <peterx@...hat.com>,
	Muchun Song <muchun.song@...ux.dev>,
	David Hildenbrand <david@...hat.com>,
	SeongJae Park <sj@...nel.org>,
	Miaohe Lin <linmiaohe@...wei.com>,
	Michal Hocko <mhocko@...e.com>,
	Matthew Wilcox <willy@...radead.org>,
	Christophe Leroy <christophe.leroy@...roup.eu>,
	Oscar Salvador <osalvador@...e.de>
Subject: [PATCH 27/45] mm/damon: Create damon_young_pud_entry to handle PUD-mapped hugetlb vmas

Normal THP cannot be PUD-mapped (besides devmap), but hugetlb can, so create
damon_young_pud_entry in order to handle PUD-mapped hugetlb vmas.

Signed-off-by: Oscar Salvador <osalvador@...e.de>
---
 mm/damon/vaddr.c | 34 ++++++++++++++++++++++++++++++++++
 1 file changed, 34 insertions(+)

diff --git a/mm/damon/vaddr.c b/mm/damon/vaddr.c
index 00d32beffe38..2d5ad47b9dae 100644
--- a/mm/damon/vaddr.c
+++ b/mm/damon/vaddr.c
@@ -434,6 +434,39 @@ struct damon_young_walk_private {
 	bool young;
 };
 
+static int damon_young_pud_entry(pmd_t *pud, unsigned long addr,
+				 unsigned long next, struct mm_walk *walk)
+{
+#ifdef CONFIG_PGTABLE_HAS_HUGE_LEAVES
+	spinlock_t *ptl;
+	struct folio *folio;
+	struct damon_young_walk_private *priv = walk->private;
+
+	ptl = pud_huge_lock(vma, pud);
+	if (!ptl)
+		return 0;
+
+	if (!pud_present(*pud))
+		goto out;
+
+	folio = pfn_folio(pud_pfn(*pud));
+	if (!folio)
+		goto out;
+	folio_get(folio);
+
+	if (pud_young(pmde) || !folio_test_idle(folio) ||
+	    mmu_notifier_test_young(walk->mm, addr))
+		priv->young = true;
+
+	*priv->folio_sz = huge_page_size(h);
+	folio_put(folio);
+out:
+	spin_unlock(ptl);
+#endif
+	return 0;
+}
+
+
 static int damon_young_pmd_entry(pmd_t *pmd, unsigned long addr,
 		unsigned long next, struct mm_walk *walk)
 {
@@ -537,6 +570,7 @@ static int damon_young_hugetlb_entry(pte_t *pte, unsigned long hmask,
 #endif /* CONFIG_HUGETLB_PAGE */
 
 static const struct mm_walk_ops damon_young_ops = {
+	.pud_entry = damon_young_pud_entry,
 	.pmd_entry = damon_young_pmd_entry,
 	.hugetlb_entry = damon_young_hugetlb_entry,
 	.walk_lock = PGWALK_RDLOCK,
-- 
2.26.2