--- zzzz-none-000/linux-3.10.107/include/linux/pagemap.h	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/include/linux/pagemap.h	2021-02-04 17:41:59.000000000 +0000
@@ -24,7 +24,7 @@
 	AS_ENOSPC	= __GFP_BITS_SHIFT + 1,	/* ENOSPC on async write */
 	AS_MM_ALL_LOCKS	= __GFP_BITS_SHIFT + 2,	/* under mm_take_all_locks() */
 	AS_UNEVICTABLE	= __GFP_BITS_SHIFT + 3,	/* e.g., ramdisk, SHM_LOCK */
-	AS_BALLOON_MAP  = __GFP_BITS_SHIFT + 4, /* balloon page special map */
+	AS_EXITING	= __GFP_BITS_SHIFT + 4, /* final truncate in progress */
 };
 
 static inline void mapping_set_error(struct address_space *mapping, int error)
@@ -54,24 +54,26 @@
 	return !!mapping;
 }
 
-static inline void mapping_set_balloon(struct address_space *mapping)
+static inline void mapping_set_exiting(struct address_space *mapping)
 {
-	set_bit(AS_BALLOON_MAP, &mapping->flags);
+	set_bit(AS_EXITING, &mapping->flags);
 }
 
-static inline void mapping_clear_balloon(struct address_space *mapping)
+static inline int mapping_exiting(struct address_space *mapping)
 {
-	clear_bit(AS_BALLOON_MAP, &mapping->flags);
+	return test_bit(AS_EXITING, &mapping->flags);
 }
 
-static inline int mapping_balloon(struct address_space *mapping)
+static inline gfp_t mapping_gfp_mask(struct address_space * mapping)
 {
-	return mapping && test_bit(AS_BALLOON_MAP, &mapping->flags);
+	return (__force gfp_t)mapping->flags & __GFP_BITS_MASK;
 }
 
-static inline gfp_t mapping_gfp_mask(struct address_space * mapping)
+/* Restricts the given gfp_mask to what the mapping allows. */
+static inline gfp_t mapping_gfp_constraint(struct address_space *mapping,
+		gfp_t gfp_mask)
 {
-	return (__force gfp_t)mapping->flags & __GFP_BITS_MASK;
+	return mapping_gfp_mask(mapping) & gfp_mask;
 }
 
 /*
@@ -85,7 +87,7 @@
 }
 
 /*
- * The page cache can done in larger chunks than
+ * The page cache can be done in larger chunks than
  * one page, because it allows for more efficient
  * throughput (it can then be mapped into user
  * space in smaller chunks for same flexibility).
@@ -99,7 +101,7 @@
 
 #define page_cache_get(page)		get_page(page)
 #define page_cache_release(page)	put_page(page)
-void release_pages(struct page **pages, int nr, int cold);
+void release_pages(struct page **pages, int nr, bool cold);
 
 /*
  * speculatively take a reference to a page.
@@ -162,7 +164,7 @@
 	 * disabling preempt, and hence no need for the "speculative get" that
 	 * SMP requires.
 	 */
-	VM_BUG_ON(page_count(page) == 0);
+	VM_BUG_ON_PAGE(page_count(page) == 0, page);
 	atomic_inc(&page->_count);
 
 #else
@@ -175,7 +177,7 @@
 		return 0;
 	}
 #endif
-	VM_BUG_ON(PageTail(page));
+	VM_BUG_ON_PAGE(PageTail(page), page);
 
 	return 1;
 }
@@ -191,14 +193,14 @@
 # ifdef CONFIG_PREEMPT_COUNT
 	VM_BUG_ON(!in_atomic());
 # endif
-	VM_BUG_ON(page_count(page) == 0);
+	VM_BUG_ON_PAGE(page_count(page) == 0, page);
 	atomic_add(count, &page->_count);
 
 #else
 	if (unlikely(!atomic_add_unless(&page->_count, count, 0)))
 		return 0;
 #endif
-	VM_BUG_ON(PageCompound(page) && page != compound_head(page));
+	VM_BUG_ON_PAGE(PageCompound(page) && page != compound_head(page), page);
 
 	return 1;
 }
@@ -210,7 +212,7 @@
 
 static inline void page_unfreeze_refs(struct page *page, int count)
 {
-	VM_BUG_ON(page_count(page) != 0);
+	VM_BUG_ON_PAGE(page_count(page) != 0, page);
 	VM_BUG_ON(count == 0);
 
 	atomic_set(&page->_count, count);
@@ -243,12 +245,116 @@
 
 typedef int filler_t(void *, struct page *);
 
-extern struct page * find_get_page(struct address_space *mapping,
-				pgoff_t index);
-extern struct page * find_lock_page(struct address_space *mapping,
-				pgoff_t index);
-extern struct page * find_or_create_page(struct address_space *mapping,
-				pgoff_t index, gfp_t gfp_mask);
+pgoff_t page_cache_next_hole(struct address_space *mapping,
+			     pgoff_t index, unsigned long max_scan);
+pgoff_t page_cache_prev_hole(struct address_space *mapping,
+			     pgoff_t index, unsigned long max_scan);
+
+#define FGP_ACCESSED		0x00000001
+#define FGP_LOCK		0x00000002
+#define FGP_CREAT		0x00000004
+#define FGP_WRITE		0x00000008
+#define FGP_NOFS		0x00000010
+#define FGP_NOWAIT		0x00000020
+
+struct page *pagecache_get_page(struct address_space *mapping, pgoff_t offset,
+		int fgp_flags, gfp_t cache_gfp_mask);
+
+/**
+ * find_get_page - find and get a page reference
+ * @mapping: the address_space to search
+ * @offset: the page index
+ *
+ * Looks up the page cache slot at @mapping & @offset.  If there is a
+ * page cache page, it is returned with an increased refcount.
+ *
+ * Otherwise, %NULL is returned.
+ */
+static inline struct page *find_get_page(struct address_space *mapping,
+					pgoff_t offset)
+{
+	return pagecache_get_page(mapping, offset, 0, 0);
+}
+
+static inline struct page *find_get_page_flags(struct address_space *mapping,
+					pgoff_t offset, int fgp_flags)
+{
+	return pagecache_get_page(mapping, offset, fgp_flags, 0);
+}
+
+/**
+ * find_lock_page - locate, pin and lock a pagecache page
+ * pagecache_get_page - find and get a page reference
+ * @mapping: the address_space to search
+ * @offset: the page index
+ *
+ * Looks up the page cache slot at @mapping & @offset.  If there is a
+ * page cache page, it is returned locked and with an increased
+ * refcount.
+ *
+ * Otherwise, %NULL is returned.
+ *
+ * find_lock_page() may sleep.
+ */
+static inline struct page *find_lock_page(struct address_space *mapping,
+					pgoff_t offset)
+{
+	return pagecache_get_page(mapping, offset, FGP_LOCK, 0);
+}
+
+/**
+ * find_or_create_page - locate or add a pagecache page
+ * @mapping: the page's address_space
+ * @index: the page's index into the mapping
+ * @gfp_mask: page allocation mode
+ *
+ * Looks up the page cache slot at @mapping & @offset.  If there is a
+ * page cache page, it is returned locked and with an increased
+ * refcount.
+ *
+ * If the page is not present, a new page is allocated using @gfp_mask
+ * and added to the page cache and the VM's LRU list.  The page is
+ * returned locked and with an increased refcount.
+ *
+ * On memory exhaustion, %NULL is returned.
+ *
+ * find_or_create_page() may sleep, even if @gfp_flags specifies an
+ * atomic allocation!
+ */
+static inline struct page *find_or_create_page(struct address_space *mapping,
+					pgoff_t offset, gfp_t gfp_mask)
+{
+	return pagecache_get_page(mapping, offset,
+					FGP_LOCK|FGP_ACCESSED|FGP_CREAT,
+					gfp_mask);
+}
+
+/**
+ * grab_cache_page_nowait - returns locked page at given index in given cache
+ * @mapping: target address_space
+ * @index: the page index
+ *
+ * Same as grab_cache_page(), but do not wait if the page is unavailable.
+ * This is intended for speculative data generators, where the data can
+ * be regenerated if the page couldn't be grabbed.  This routine should
+ * be safe to call while holding the lock for another page.
+ *
+ * Clear __GFP_FS when allocating the page to avoid recursion into the fs
+ * and deadlock against the caller's locked page.
+ */
+static inline struct page *grab_cache_page_nowait(struct address_space *mapping,
+				pgoff_t index)
+{
+	return pagecache_get_page(mapping, index,
+			FGP_LOCK|FGP_CREAT|FGP_NOFS|FGP_NOWAIT,
+			mapping_gfp_mask(mapping));
+}
+
+struct page *find_get_entry(struct address_space *mapping, pgoff_t offset);
+struct page *find_lock_entry(struct address_space *mapping, pgoff_t offset);
+unsigned find_get_entries(struct address_space *mapping, pgoff_t start,
+			  unsigned int nr_entries, struct page **entries,
+			  pgoff_t *indices);
 unsigned find_get_pages(struct address_space *mapping, pgoff_t start,
 			unsigned int nr_pages, struct page **pages);
 unsigned find_get_pages_contig(struct address_space *mapping, pgoff_t start,
@@ -268,10 +374,6 @@
 	return find_or_create_page(mapping, index, mapping_gfp_mask(mapping));
 }
 
-extern struct page * grab_cache_page_nowait(struct address_space *mapping,
-				pgoff_t index);
-extern struct page * read_cache_page_async(struct address_space *mapping,
-				pgoff_t index, filler_t *filler, void *data);
 extern struct page * read_cache_page(struct address_space *mapping,
 				pgoff_t index, filler_t *filler, void *data);
 extern struct page * read_cache_page_gfp(struct address_space *mapping,
@@ -279,19 +381,23 @@
 extern int read_cache_pages(struct address_space *mapping,
 		struct list_head *pages, filler_t *filler, void *data);
 
-static inline struct page *read_mapping_page_async(
-				struct address_space *mapping,
+static inline struct page *read_mapping_page(struct address_space *mapping,
 				pgoff_t index, void *data)
 {
 	filler_t *filler = (filler_t *)mapping->a_ops->readpage;
-	return read_cache_page_async(mapping, index, filler, data);
+	return read_cache_page(mapping, index, filler, data);
 }
 
-static inline struct page *read_mapping_page(struct address_space *mapping,
-				pgoff_t index, void *data)
+/*
+ * Get the offset in PAGE_SIZE.
+ * (TODO: hugepage should have ->index in PAGE_SIZE)
+ */
+static inline pgoff_t page_to_pgoff(struct page *page)
 {
-	filler_t *filler = (filler_t *)mapping->a_ops->readpage;
-	return read_cache_page(mapping, index, filler, data);
+	if (unlikely(PageHeadHuge(page)))
+		return page->index << compound_order(page);
+	else
+		return page->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT);
 }
 
 /*
@@ -368,6 +474,9 @@
 /*
  * lock_page_or_retry - Lock the page, unless this would block and the
  * caller indicated that it can handle a retry.
+ *
+ * Return value and mmap_sem implications depend on flags; see
+ * __lock_page_or_retry().
  */
 static inline int lock_page_or_retry(struct page *page, struct mm_struct *mm,
 				     unsigned int flags)
@@ -377,12 +486,14 @@
 }
 
 /*
- * This is exported only for wait_on_page_locked/wait_on_page_writeback.
- * Never use this directly!
+ * This is exported only for wait_on_page_locked/wait_on_page_writeback,
+ * and for filesystems which need to wait on PG_private.
  */
 extern void wait_on_page_bit(struct page *page, int bit_nr);
 
 extern int wait_on_page_bit_killable(struct page *page, int bit_nr);
+extern int wait_on_page_bit_killable_timeout(struct page *page,
+					     int bit_nr, unsigned long timeout);
 
 static inline int wait_on_page_locked_killable(struct page *page)
 {
@@ -391,6 +502,12 @@
 	return 0;
 }
 
+extern wait_queue_head_t *page_waitqueue(struct page *page);
+static inline void wake_up_page(struct page *page, int bit)
+{
+	__wake_up_bit(page_waitqueue(page), &page->flags, bit);
+}
+
 /* 
  * Wait for a page to be unlocked.
  *
@@ -416,6 +533,8 @@
 extern void end_page_writeback(struct page *page);
 void wait_for_stable_page(struct page *page);
 
+void page_endio(struct page *page, int rw, int err);
+
 /*
  * Add an arbitrary waiter to a page's wait queue
  */
@@ -539,7 +658,8 @@
 int add_to_page_cache_lru(struct page *page, struct address_space *mapping,
 				pgoff_t index, gfp_t gfp_mask);
 extern void delete_from_page_cache(struct page *page);
-extern void __delete_from_page_cache(struct page *page);
+extern void __delete_from_page_cache(struct page *page, void *shadow,
+				     struct mem_cgroup *memcg);
 int replace_page_cache_page(struct page *old, struct page *new, gfp_t gfp_mask);
 
 /*
@@ -558,4 +678,10 @@
 	return error;
 }
 
+static inline unsigned long dir_pages(struct inode *inode)
+{
+	return (unsigned long)(inode->i_size + PAGE_CACHE_SIZE - 1) >>
+			       PAGE_CACHE_SHIFT;
+}
+
 #endif /* _LINUX_PAGEMAP_H */