[PATCH 13/13] PCI/P2PDMA: enable compound page support for p2pdma memory

Hou Tao houtao at huaweicloud.com
Fri Dec 19 20:04:46 PST 2025


From: Hou Tao <houtao1 at huawei.com>

Compound page support for P2PDMA memory in both kernel and user space is
now in place. Enable it by allowing PUD_SIZE and PMD_SIZE alignment.

Signed-off-by: Hou Tao <houtao1 at huawei.com>
---
 drivers/pci/p2pdma.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/drivers/pci/p2pdma.c b/drivers/pci/p2pdma.c
index 4a133219ac43..969bdacdcf8b 100644
--- a/drivers/pci/p2pdma.c
+++ b/drivers/pci/p2pdma.c
@@ -452,9 +452,19 @@ static inline int pci_p2pdma_check_pagemap_align(struct pci_dev *pdev, int bar,
 						 u64 size, size_t align,
 						 u64 offset)
 {
+	if (has_transparent_pud_hugepage() && align == PUD_SIZE)
+		goto more_check;
+	if (has_transparent_hugepage() && align == PMD_SIZE)
+		goto more_check;
 	if (align == PAGE_SIZE)
 		return 0;
 	return -EINVAL;
+
+more_check:
+	if (IS_ALIGNED(pci_resource_start(pdev, bar), align) &&
+	    IS_ALIGNED(size, align) && IS_ALIGNED(offset, align))
+		return 0;
+	return -EINVAL;
 }
 
 /**
-- 
2.29.2




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