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From:   Christoph Hellwig <hch@lst.de>
To:     Andrew Morton <akpm@linux-foundation.org>,
        Dan Williams <dan.j.williams@intel.com>
Cc:     Felix Kuehling <Felix.Kuehling@amd.com>,
        Alex Deucher <alexander.deucher@amd.com>,
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        Alistair Popple <apopple@nvidia.com>,
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        Ralph Campbell <rcampbell@nvidia.com>,
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Subject: [PATCH 09/27] mm: generalize the pgmap based page_free infrastructure
Date:   Thu, 10 Feb 2022 08:28:10 +0100
Message-Id: <20220210072828.2930359-10-hch@lst.de>
In-Reply-To: <20220210072828.2930359-1-hch@lst.de>
References: <20220210072828.2930359-1-hch@lst.de>
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Key off on the existence of ->page_free to prepare for adding support for
more pgmap types that are device managed and thus need the free callback.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 mm/memremap.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/mm/memremap.c b/mm/memremap.c
index fef5734d5e4933..e00ffcdba7b632 100644
--- a/mm/memremap.c
+++ b/mm/memremap.c
@@ -452,7 +452,7 @@ EXPORT_SYMBOL_GPL(get_dev_pagemap);
 
 void free_zone_device_page(struct page *page)
 {
-	if (WARN_ON_ONCE(!is_device_private_page(page)))
+	if (WARN_ON_ONCE(!page->pgmap->ops || !page->pgmap->ops->page_free))
 		return;
 
 	__ClearPageWaiters(page);
@@ -460,7 +460,7 @@ void free_zone_device_page(struct page *page)
 	mem_cgroup_uncharge(page_folio(page));
 
 	/*
-	 * When a device_private page is freed, the page->mapping field
+	 * When a device managed page is freed, the page->mapping field
 	 * may still contain a (stale) mapping value. For example, the
 	 * lower bits of page->mapping may still identify the page as an
 	 * anonymous page. Ultimately, this entire field is just stale
-- 
2.30.2