1 files changed, 23 insertions, 26 deletions

diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c
index be4be99304bc..9c94ed8c3ab0 100644
--- a/fs/hugetlbfs/inode.c
+++ b/fs/hugetlbfs/inode.c
@@ -192,37 +192,25 @@ hugetlb_get_unmapped_area(struct file *file, unsigned long addr,
  * Someone wants to read @bytes from a HWPOISON hugetlb @folio from @offset.
  * Returns the maximum number of bytes one can read without touching the 1st raw
  * HWPOISON page.
- *
- * The implementation borrows the iteration logic from copy_page_to_iter*.
  */
 static size_t adjust_range_hwpoison(struct folio *folio, size_t offset,
 		size_t bytes)
 {
-	struct page *page;
-	size_t n = 0;
-	size_t res = 0;
-
-	/* First page to start the loop. */
-	page = folio_page(folio, offset / PAGE_SIZE);
-	offset %= PAGE_SIZE;
-	while (1) {
-		if (is_raw_hwpoison_page_in_hugepage(page))
-			break;
+	struct page *page = folio_page(folio, offset / PAGE_SIZE);
+	size_t safe_bytes;
 
-		/* Safe to read n bytes without touching HWPOISON subpage. */
-		n = min(bytes, (size_t)PAGE_SIZE - offset);
-		res += n;
-		bytes -= n;
-		if (!bytes || !n)
+	if (is_raw_hwpoison_page_in_hugepage(page))
+		return 0;
+	/* Safe to read the remaining bytes in this page. */
+	safe_bytes = PAGE_SIZE - (offset % PAGE_SIZE);
+	page++;
+
+	/* Check each remaining page as long as we are not done yet. */
+	for (; safe_bytes < bytes; safe_bytes += PAGE_SIZE, page++)
+		if (is_raw_hwpoison_page_in_hugepage(page))
 			break;
-		offset += n;
-		if (offset == PAGE_SIZE) {
-			page = nth_page(page, 1);
-			offset = 0;
-		}
-	}
 
-	return res;
+	return min(safe_bytes, bytes);
 }
 
 /*
@@ -490,6 +478,14 @@ hugetlb_vmdelete_list(struct rb_root_cached *root, pgoff_t start, pgoff_t end,
 		if (!hugetlb_vma_trylock_write(vma))
 			continue;
 
+		/*
+		 * Skip VMAs without shareable locks. Per the design in commit
+		 * 40549ba8f8e0, these will be handled by remove_inode_hugepages()
+		 * called after this function with proper locking.
+		 */
+		if (!__vma_shareable_lock(vma))
+			goto skip;
+
 		v_start = vma_offset_start(vma, start);
 		v_end = vma_offset_end(vma, end);
 
@@ -500,6 +496,7 @@ hugetlb_vmdelete_list(struct rb_root_cached *root, pgoff_t start, pgoff_t end,
 		 * vmas.  Therefore, lock is not held when calling
 		 * unmap_hugepage_range for private vmas.
 		 */
+skip:
 		hugetlb_vma_unlock_write(vma);
 	}
 }
@@ -1054,7 +1051,7 @@ static int hugetlbfs_migrate_folio(struct address_space *mapping,
 	int rc;
 
 	rc = migrate_huge_page_move_mapping(mapping, dst, src);
-	if (rc != MIGRATEPAGE_SUCCESS)
+	if (rc)
 		return rc;
 
 	if (hugetlb_folio_subpool(src)) {
@@ -1065,7 +1062,7 @@ static int hugetlbfs_migrate_folio(struct address_space *mapping,
 
 	folio_migrate_flags(dst, src);
 
-	return MIGRATEPAGE_SUCCESS;
+	return 0;
 }
 #else
 #define hugetlbfs_migrate_folio NULL