diff options
Diffstat (limited to 'mm/memory.c')
| -rw-r--r-- | mm/memory.c | 61 |
1 files changed, 61 insertions, 0 deletions
diff --git a/mm/memory.c b/mm/memory.c index 886033b95fd2..079eeac0b009 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -49,6 +49,7 @@ #include <linux/swap.h> #include <linux/highmem.h> #include <linux/pagemap.h> +#include <linux/memremap.h> #include <linux/ksm.h> #include <linux/rmap.h> #include <linux/export.h> @@ -956,6 +957,35 @@ copy_one_pte(struct mm_struct *dst_mm, struct mm_struct *src_mm, pte = pte_swp_mksoft_dirty(pte); set_pte_at(src_mm, addr, src_pte, pte); } + } else if (is_device_private_entry(entry)) { + page = device_private_entry_to_page(entry); + + /* + * Update rss count even for unaddressable pages, as + * they should treated just like normal pages in this + * respect. + * + * We will likely want to have some new rss counters + * for unaddressable pages, at some point. But for now + * keep things as they are. + */ + get_page(page); + rss[mm_counter(page)]++; + page_dup_rmap(page, false); + + /* + * We do not preserve soft-dirty information, because so + * far, checkpoint/restore is the only feature that + * requires that. And checkpoint/restore does not work + * when a device driver is involved (you cannot easily + * save and restore device driver state). + */ + if (is_write_device_private_entry(entry) && + is_cow_mapping(vm_flags)) { + make_device_private_entry_read(&entry); + pte = swp_entry_to_pte(entry); + set_pte_at(src_mm, addr, src_pte, pte); + } } goto out_set_pte; } @@ -1274,6 +1304,29 @@ again: } continue; } + + entry = pte_to_swp_entry(ptent); + if (non_swap_entry(entry) && is_device_private_entry(entry)) { + struct page *page = device_private_entry_to_page(entry); + + if (unlikely(details && details->check_mapping)) { + /* + * unmap_shared_mapping_pages() wants to + * invalidate cache without truncating: + * unmap shared but keep private pages. + */ + if (details->check_mapping != + page_rmapping(page)) + continue; + } + + pte_clear_not_present_full(mm, addr, pte, tlb->fullmm); + rss[mm_counter(page)]--; + page_remove_rmap(page, false); + put_page(page); + continue; + } + /* If details->check_mapping, we leave swap entries. */ if (unlikely(details)) continue; @@ -2776,6 +2829,14 @@ int do_swap_page(struct vm_fault *vmf) if (is_migration_entry(entry)) { migration_entry_wait(vma->vm_mm, vmf->pmd, vmf->address); + } else if (is_device_private_entry(entry)) { + /* + * For un-addressable device memory we call the pgmap + * fault handler callback. The callback must migrate + * the page back to some CPU accessible page. + */ + ret = device_private_entry_fault(vma, vmf->address, entry, + vmf->flags, vmf->pmd); } else if (is_hwpoison_entry(entry)) { ret = VM_FAULT_HWPOISON; } else { |