This case is used to migrate pages from device memory, back to system
memory. Device coherent type memory is cache coherent from device and CPU
point of view.
Signed-off-by: Alex Sierra <alex.sierra@xxxxxxx>
---
v2:
condition added when migrations from device coherent pages.
---
include/linux/migrate.h | 1 +
mm/migrate.c | 9 +++++++--
2 files changed, 8 insertions(+), 2 deletions(-)
diff --git a/include/linux/migrate.h b/include/linux/migrate.h
index 4bb4e519e3f5..b1cae5073d69 100644
--- a/include/linux/migrate.h
+++ b/include/linux/migrate.h
@@ -156,6 +156,7 @@ static inline unsigned long migrate_pfn(unsigned long pfn)
enum migrate_vma_direction {
MIGRATE_VMA_SELECT_SYSTEM = 1 << 0,
MIGRATE_VMA_SELECT_DEVICE_PRIVATE = 1 << 1,
+ MIGRATE_VMA_SELECT_DEVICE_COHERENT = 1 << 2,
};
struct migrate_vma {
diff --git a/mm/migrate.c b/mm/migrate.c
index 2bda612f3650..b40cd5a69f65 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -2406,8 +2406,6 @@ static int migrate_vma_collect_pmd(pmd_t *pmdp,
if (is_write_device_private_entry(entry))
mpfn |= MIGRATE_PFN_WRITE;
} else {
- if (!(migrate->flags & MIGRATE_VMA_SELECT_SYSTEM))
- goto next;
pfn = pte_pfn(pte);
if (is_zero_pfn(pfn)) {
mpfn = MIGRATE_PFN_MIGRATE;
@@ -2415,6 +2413,13 @@ static int migrate_vma_collect_pmd(pmd_t *pmdp,
goto next;
}
page = vm_normal_page(migrate->vma, addr, pte);
+ if (!is_zone_device_page(page) &&
+ !(migrate->flags & MIGRATE_VMA_SELECT_SYSTEM))
+ goto next;
+ if (is_zone_device_page(page) &&
+ (!(migrate->flags & MIGRATE_VMA_SELECT_DEVICE_COHERENT) ||
+ page->pgmap->owner != migrate->pgmap_owner))
+ goto next;
mpfn = migrate_pfn(pfn) | MIGRATE_PFN_MIGRATE;
mpfn |= pte_write(pte) ? MIGRATE_PFN_WRITE : 0;
}
--
2.32.0
