1 files changed, 12 insertions, 53 deletions

diff --git a/mm/memory.c b/mm/memory.c
index 96f1d473c89a..89325f9c6173 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  *  linux/mm/memory.c
  *
@@ -570,8 +571,8 @@ static void print_bad_pte(struct vm_area_struct *vma, unsigned long addr,
  * PFNMAP mappings in order to support COWable mappings.
  *
  */
-struct page *_vm_normal_page(struct vm_area_struct *vma, unsigned long addr,
-			     pte_t pte, bool with_public_device)
+struct page *vm_normal_page(struct vm_area_struct *vma, unsigned long addr,
+			    pte_t pte)
 {
 	unsigned long pfn = pte_pfn(pte);
 
@@ -584,29 +585,6 @@ struct page *_vm_normal_page(struct vm_area_struct *vma, unsigned long addr,
 			return NULL;
 		if (is_zero_pfn(pfn))
 			return NULL;
-
-		/*
-		 * Device public pages are special pages (they are ZONE_DEVICE
-		 * pages but different from persistent memory). They behave
-		 * allmost like normal pages. The difference is that they are
-		 * not on the lru and thus should never be involve with any-
-		 * thing that involve lru manipulation (mlock, numa balancing,
-		 * ...).
-		 *
-		 * This is why we still want to return NULL for such page from
-		 * vm_normal_page() so that we do not have to special case all
-		 * call site of vm_normal_page().
-		 */
-		if (likely(pfn <= highest_memmap_pfn)) {
-			struct page *page = pfn_to_page(pfn);
-
-			if (is_device_public_page(page)) {
-				if (with_public_device)
-					return page;
-				return NULL;
-			}
-		}
-
 		if (pte_devmap(pte))
 			return NULL;
 
@@ -796,17 +774,6 @@ copy_one_pte(struct mm_struct *dst_mm, struct mm_struct *src_mm,
 		rss[mm_counter(page)]++;
 	} else if (pte_devmap(pte)) {
 		page = pte_page(pte);
-
-		/*
-		 * Cache coherent device memory behave like regular page and
-		 * not like persistent memory page. For more informations see
-		 * MEMORY_DEVICE_CACHE_COHERENT in memory_hotplug.h
-		 */
-		if (is_device_public_page(page)) {
-			get_page(page);
-			page_dup_rmap(page, false);
-			rss[mm_counter(page)]++;
-		}
 	}
 
 out_set_pte:
@@ -1062,7 +1029,7 @@ again:
 		if (pte_present(ptent)) {
 			struct page *page;
 
-			page = _vm_normal_page(vma, addr, ptent, true);
+			page = vm_normal_page(vma, addr, ptent);
 			if (unlikely(details) && page) {
 				/*
 				 * unmap_shared_mapping_pages() wants to
@@ -1474,8 +1441,6 @@ static int insert_page(struct vm_area_struct *vma, unsigned long addr,
 	set_pte_at(mm, addr, pte, mk_pte(page, prot));
 
 	retval = 0;
-	pte_unmap_unlock(pte, ptl);
-	return retval;
 out_unlock:
 	pte_unmap_unlock(pte, ptl);
 out:
@@ -1546,7 +1511,7 @@ static int __vm_map_pages(struct vm_area_struct *vma, struct page **pages,
 	int ret, i;
 
 	/* Fail if the user requested offset is beyond the end of the object */
-	if (offset > num)
+	if (offset >= num)
 		return -ENXIO;
 
 	/* Fail if the user requested size exceeds available object size */
@@ -2037,7 +2002,6 @@ static int apply_to_pte_range(struct mm_struct *mm, pmd_t *pmd,
 {
 	pte_t *pte;
 	int err;
-	pgtable_t token;
 	spinlock_t *uninitialized_var(ptl);
 
 	pte = (mm == &init_mm) ?
@@ -2050,10 +2014,8 @@ static int apply_to_pte_range(struct mm_struct *mm, pmd_t *pmd,
 
 	arch_enter_lazy_mmu_mode();
 
-	token = pmd_pgtable(*pmd);
-
 	do {
-		err = fn(pte++, token, addr, data);
+		err = fn(pte++, addr, data);
 		if (err)
 			break;
 	} while (addr += PAGE_SIZE, addr != end);
@@ -2781,13 +2743,8 @@ vm_fault_t do_swap_page(struct vm_fault *vmf)
 			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);
+			vmf->page = device_private_entry_to_page(entry);
+			ret = vmf->page->pgmap->ops->migrate_to_ram(vmf);
 		} else if (is_hwpoison_entry(entry)) {
 			ret = VM_FAULT_HWPOISON;
 		} else {
@@ -2806,7 +2763,7 @@ vm_fault_t do_swap_page(struct vm_fault *vmf)
 		struct swap_info_struct *si = swp_swap_info(entry);
 
 		if (si->flags & SWP_SYNCHRONOUS_IO &&
-				__swap_count(si, entry) == 1) {
+				__swap_count(entry) == 1) {
 			/* skip swapcache */
 			page = alloc_page_vma(GFP_HIGHUSER_MOVABLE, vma,
 							vmf->address);
@@ -4348,7 +4305,9 @@ int __access_remote_vm(struct task_struct *tsk, struct mm_struct *mm,
 	void *old_buf = buf;
 	int write = gup_flags & FOLL_WRITE;
 
-	down_read(&mm->mmap_sem);
+	if (down_read_killable(&mm->mmap_sem))
+		return 0;
+
 	/* ignore errors, just check how much was successfully transferred */
 	while (len) {
 		int bytes, ret, offset;