From: Alex Sierra <alex.sierra@xxxxxxx>
pages in device mapping refcounts are 1-based, instead
of 0-based. If refcount 1, means it can be freed.
This logic is not set for Generic memory type. Therefore,
its release is threated as a normal page, instead of
the callback device driver release it.
Signed-off-by: Alex Sierra <alex.sierra@xxxxxxx>
---
include/linux/mm.h | 1 +
mm/memremap.c | 5 ++++-
2 files changed, 5 insertions(+), 1 deletion(-)
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 1af7b9b76948..83bd2f3e111b 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1130,6 +1130,7 @@ static inline bool page_is_devmap_managed(struct page *page)
switch (page->pgmap->type) {
case MEMORY_DEVICE_PRIVATE:
case MEMORY_DEVICE_FS_DAX:
+ case MEMORY_DEVICE_GENERIC:
return true;
default:
break;
diff --git a/mm/memremap.c b/mm/memremap.c
index 16b2fb482da1..d2563fbcf987 100644
--- a/mm/memremap.c
+++ b/mm/memremap.c
@@ -44,6 +44,7 @@ EXPORT_SYMBOL(devmap_managed_key);
static void devmap_managed_enable_put(struct dev_pagemap *pgmap)
{
if (pgmap->type == MEMORY_DEVICE_PRIVATE ||
+ pgmap->type == MEMORY_DEVICE_GENERIC ||
pgmap->type == MEMORY_DEVICE_FS_DAX)
static_branch_dec(&devmap_managed_key);
}
@@ -51,6 +52,7 @@ static void devmap_managed_enable_put(struct dev_pagemap *pgmap)
static void devmap_managed_enable_get(struct dev_pagemap *pgmap)
{
if (pgmap->type == MEMORY_DEVICE_PRIVATE ||
+ pgmap->type == MEMORY_DEVICE_GENERIC ||
pgmap->type == MEMORY_DEVICE_FS_DAX)
static_branch_inc(&devmap_managed_key);
}
@@ -480,7 +482,8 @@ EXPORT_SYMBOL_GPL(get_dev_pagemap);
void free_devmap_managed_page(struct page *page)
{
/* notify page idle for dax */
- if (!is_device_private_page(page)) {
+ if (!(is_device_private_page(page) ||
+ is_device_generic_page(page))) {
wake_up_var(&page->_refcount);
return;
}
--
2.31.1
