Date:   Sat, 18 Feb 2023 00:27:59 +0000
In-Reply-To: <20230218002819.1486479-1-jthoughton@google.com>
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References: <20230218002819.1486479-1-jthoughton@google.com>
Message-ID: <20230218002819.1486479-27-jthoughton@google.com>
Subject: [PATCH v2 26/46] mm: rmap: provide pte_order in page_vma_mapped_walk
From:   James Houghton <jthoughton@google.com>
To:     Mike Kravetz <mike.kravetz@oracle.com>,
        Muchun Song <songmuchun@bytedance.com>,
        Peter Xu <peterx@redhat.com>,
        Andrew Morton <akpm@linux-foundation.org>
Cc:     David Hildenbrand <david@redhat.com>,
        David Rientjes <rientjes@google.com>,
        Axel Rasmussen <axelrasmussen@google.com>,
        Mina Almasry <almasrymina@google.com>,
        "Zach O'Keefe" <zokeefe@google.com>,
        Manish Mishra <manish.mishra@nutanix.com>,
        Naoya Horiguchi <naoya.horiguchi@nec.com>,
        "Dr . David Alan Gilbert" <dgilbert@redhat.com>,
        "Matthew Wilcox (Oracle)" <willy@infradead.org>,
        Vlastimil Babka <vbabka@suse.cz>,
        Baolin Wang <baolin.wang@linux.alibaba.com>,
        Miaohe Lin <linmiaohe@huawei.com>,
        Yang Shi <shy828301@gmail.com>,
        Frank van der Linden <fvdl@google.com>,
        Jiaqi Yan <jiaqiyan@google.com>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org,
        James Houghton <jthoughton@google.com>
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

page_vma_mapped_walk callers will need this information to know how
HugeTLB pages are mapped. pte_order only applies if pte is not NULL.

Signed-off-by: James Houghton <jthoughton@google.com>

diff --git a/include/linux/rmap.h b/include/linux/rmap.h
index a4570da03e58..87a2c7f422bf 100644
--- a/include/linux/rmap.h
+++ b/include/linux/rmap.h
@@ -387,6 +387,7 @@ struct page_vma_mapped_walk {
 	pmd_t *pmd;
 	pte_t *pte;
 	spinlock_t *ptl;
+	unsigned int pte_order;
 	unsigned int flags;
 };
 
diff --git a/mm/page_vma_mapped.c b/mm/page_vma_mapped.c
index 4e448cfbc6ef..08295b122ad6 100644
--- a/mm/page_vma_mapped.c
+++ b/mm/page_vma_mapped.c
@@ -16,6 +16,7 @@ static inline bool not_found(struct page_vma_mapped_walk *pvmw)
 static bool map_pte(struct page_vma_mapped_walk *pvmw)
 {
 	pvmw->pte = pte_offset_map(pvmw->pmd, pvmw->address);
+	pvmw->pte_order = 0;
 	if (!(pvmw->flags & PVMW_SYNC)) {
 		if (pvmw->flags & PVMW_MIGRATION) {
 			if (!is_swap_pte(*pvmw->pte))
@@ -177,6 +178,7 @@ bool page_vma_mapped_walk(struct page_vma_mapped_walk *pvmw)
 		if (!pvmw->pte)
 			return false;
 
+		pvmw->pte_order = huge_page_order(hstate);
 		pvmw->ptl = huge_pte_lock(hstate, mm, pvmw->pte);
 		if (!check_pte(pvmw))
 			return not_found(pvmw);
@@ -272,6 +274,7 @@ bool page_vma_mapped_walk(struct page_vma_mapped_walk *pvmw)
 				}
 				pte_unmap(pvmw->pte);
 				pvmw->pte = NULL;
+				pvmw->pte_order = 0;
 				goto restart;
 			}
 			pvmw->pte++;
-- 
2.39.2.637.g21b0678d19-goog