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From: Alistair Popple <apopple@nvidia.com>
To: linux-mm@kvack.org
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	Alistair Popple <apopple@nvidia.com>
Subject: [RFC 01/10] mm/gup.c: Remove redundant check for PCI P2PDMA page
Date: Thu, 11 Apr 2024 10:57:22 +1000
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PCI P2PDMA pages are not mapped with pXX_devmap PTEs therefore the
check in __gup_device_huge() is redundant. Remove it

Signed-off-by: Alistair Popple <apopple@nvidia.com>
---
 mm/gup.c | 5 -----
 1 file changed, 5 deletions(-)

diff --git a/mm/gup.c b/mm/gup.c
index 2f8a2d8..a9c8a09 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -2683,11 +2683,6 @@ static int __gup_device_huge(unsigned long pfn, unsigned long addr,
 			break;
 		}
 
-		if (!(flags & FOLL_PCI_P2PDMA) && is_pci_p2pdma_page(page)) {
-			undo_dev_pagemap(nr, nr_start, flags, pages);
-			break;
-		}
-
 		SetPageReferenced(page);
 		pages[*nr] = page;
 		if (unlikely(try_grab_page(page, flags))) {
-- 
git-series 0.9.1