7 files changed, 82 insertions, 83 deletions

diff --git a/include/linux/backing-dev-defs.h b/include/linux/backing-dev-defs.h
index a23209b43842..1b4d69f68c33 100644
--- a/include/linux/backing-dev-defs.h
+++ b/include/linux/backing-dev-defs.h
@@ -116,6 +116,8 @@ struct bdi_writeback {
         struct list_head work_list;
         struct delayed_work dwork;      /* work item used for writeback */
 
+        struct list_head bdi_node;      /* anchored at bdi->wb_list */
+
 #ifdef CONFIG_CGROUP_WRITEBACK
         struct percpu_ref refcnt;       /* used only for !root wb's */
         struct fprop_local_percpu memcg_completions;
@@ -150,6 +152,7 @@ struct backing_dev_info {
         atomic_long_t tot_write_bandwidth;
 
         struct bdi_writeback wb;  /* the root writeback info for this bdi */
+        struct list_head wb_list; /* list of all wbs */
 #ifdef CONFIG_CGROUP_WRITEBACK
         struct radix_tree_root cgwb_tree; /* radix tree of active cgroup wbs */
         struct rb_root cgwb_congested_tree; /* their congested states */
diff --git a/include/linux/backing-dev.h b/include/linux/backing-dev.h
index d5eb4ad1c534..c85f74946a8b 100644
--- a/include/linux/backing-dev.h
+++ b/include/linux/backing-dev.h
@@ -19,13 +19,17 @@
 #include <linux/slab.h>
 
 int __must_check bdi_init(struct backing_dev_info *bdi);
-void bdi_destroy(struct backing_dev_info *bdi);
+void bdi_exit(struct backing_dev_info *bdi);
 
 __printf(3, 4)
 int bdi_register(struct backing_dev_info *bdi, struct device *parent,
                 const char *fmt, ...);
 int bdi_register_dev(struct backing_dev_info *bdi, dev_t dev);
+void bdi_unregister(struct backing_dev_info *bdi);
+
 int __must_check bdi_setup_and_register(struct backing_dev_info *, char *);
+void bdi_destroy(struct backing_dev_info *bdi);
+
 void wb_start_writeback(struct bdi_writeback *wb, long nr_pages,
                         bool range_cyclic, enum wb_reason reason);
 void wb_start_background_writeback(struct bdi_writeback *wb);
@@ -408,61 +412,6 @@ static inline void unlocked_inode_to_wb_end(struct inode *inode, bool locked)
         rcu_read_unlock();
 }
 
-struct wb_iter {
-        int                     start_memcg_id;
-        struct radix_tree_iter  tree_iter;
-        void                    **slot;
-};
-
-static inline struct bdi_writeback *__wb_iter_next(struct wb_iter *iter,
-                                                   struct backing_dev_info *bdi)
-{
-        struct radix_tree_iter *titer = &iter->tree_iter;
-
-        WARN_ON_ONCE(!rcu_read_lock_held());
-
-        if (iter->start_memcg_id >= 0) {
-                iter->slot = radix_tree_iter_init(titer, iter->start_memcg_id);
-                iter->start_memcg_id = -1;
-        } else {
-                iter->slot = radix_tree_next_slot(iter->slot, titer, 0);
-        }
-
-        if (!iter->slot)
-                iter->slot = radix_tree_next_chunk(&bdi->cgwb_tree, titer, 0);
-        if (iter->slot)
-                return *iter->slot;
-        return NULL;
-}
-
-static inline struct bdi_writeback *__wb_iter_init(struct wb_iter *iter,
-                                                   struct backing_dev_info *bdi,
-                                                   int start_memcg_id)
-{
-        iter->start_memcg_id = start_memcg_id;
-
-        if (start_memcg_id)
-                return __wb_iter_next(iter, bdi);
-        else
-                return &bdi->wb;
-}
-
-/**
- * bdi_for_each_wb - walk all wb's of a bdi in ascending memcg ID order
- * @wb_cur: cursor struct bdi_writeback pointer
- * @bdi: bdi to walk wb's of
- * @iter: pointer to struct wb_iter to be used as iteration buffer
- * @start_memcg_id: memcg ID to start iteration from
- *
- * Iterate @wb_cur through the wb's (bdi_writeback's) of @bdi in ascending
- * memcg ID order starting from @start_memcg_id.  @iter is struct wb_iter
- * to be used as temp storage during iteration.  rcu_read_lock() must be
- * held throughout iteration.
- */
-#define bdi_for_each_wb(wb_cur, bdi, iter, start_memcg_id)              \
-        for ((wb_cur) = __wb_iter_init(iter, bdi, start_memcg_id);      \
-             (wb_cur); (wb_cur) = __wb_iter_next(iter, bdi))
-
 #else   /* CONFIG_CGROUP_WRITEBACK */
 
 static inline bool inode_cgwb_enabled(struct inode *inode)
@@ -522,14 +471,6 @@ static inline void wb_blkcg_offline(struct blkcg *blkcg)
 {
 }
 
-struct wb_iter {
-        int             next_id;
-};
-
-#define bdi_for_each_wb(wb_cur, bdi, iter, start_blkcg_id)              \
-        for ((iter)->next_id = (start_blkcg_id);                        \
-             ({ (wb_cur) = !(iter)->next_id++ ? &(bdi)->wb : NULL; }); )
-
 static inline int inode_congested(struct inode *inode, int cong_bits)
 {
         return wb_congested(&inode_to_bdi(inode)->wb, cong_bits);
diff --git a/include/linux/cma.h b/include/linux/cma.h
index f7ef093ec49a..29f9e774ab76 100644
--- a/include/linux/cma.h
+++ b/include/linux/cma.h
@@ -26,6 +26,6 @@ extern int __init cma_declare_contiguous(phys_addr_t base,
 extern int cma_init_reserved_mem(phys_addr_t base, phys_addr_t size,
                                         unsigned int order_per_bit,
                                         struct cma **res_cma);
-extern struct page *cma_alloc(struct cma *cma, unsigned int count, unsigned int align);
+extern struct page *cma_alloc(struct cma *cma, size_t count, unsigned int align);
 extern bool cma_release(struct cma *cma, const struct page *pages, unsigned int count);
 #endif
diff --git a/include/linux/compiler-gcc.h b/include/linux/compiler-gcc.h
index dfaa7b3e9ae9..8efb40e61d6e 100644
--- a/include/linux/compiler-gcc.h
+++ b/include/linux/compiler-gcc.h
@@ -237,12 +237,25 @@
 #define KASAN_ABI_VERSION 3
 #endif
 
+#if GCC_VERSION >= 40902
+/*
+ * Tell the compiler that address safety instrumentation (KASAN)
+ * should not be applied to that function.
+ * Conflicts with inlining: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67368
+ */
+#define __no_sanitize_address __attribute__((no_sanitize_address))
+#endif
+
 #endif  /* gcc version >= 40000 specific checks */
 
 #if !defined(__noclone)
 #define __noclone       /* not needed */
 #endif
 
+#if !defined(__no_sanitize_address)
+#define __no_sanitize_address
+#endif
+
 /*
  * A trick to suppress uninitialized variable warning without generating any
  * code
diff --git a/include/linux/compiler.h b/include/linux/compiler.h
index c836eb2dc44d..3d7810341b57 100644
--- a/include/linux/compiler.h
+++ b/include/linux/compiler.h
@@ -198,19 +198,45 @@ void ftrace_likely_update(struct ftrace_branch_data *f, int val, int expect);
 
 #include <uapi/linux/types.h>
 
-static __always_inline void __read_once_size(const volatile void *p, void *res, int size)
+#define __READ_ONCE_SIZE                                                \
+({                                                                      \
+        switch (size) {                                                 \
+        case 1: *(__u8 *)res = *(volatile __u8 *)p; break;              \
+        case 2: *(__u16 *)res = *(volatile __u16 *)p; break;            \
+        case 4: *(__u32 *)res = *(volatile __u32 *)p; break;            \
+        case 8: *(__u64 *)res = *(volatile __u64 *)p; break;            \
+        default:                                                        \
+                barrier();                                              \
+                __builtin_memcpy((void *)res, (const void *)p, size);   \
+                barrier();                                              \
+        }                                                               \
+})
+
+static __always_inline
+void __read_once_size(const volatile void *p, void *res, int size)
 {
-        switch (size) {
-        case 1: *(__u8 *)res = *(volatile __u8 *)p; break;
-        case 2: *(__u16 *)res = *(volatile __u16 *)p; break;
-        case 4: *(__u32 *)res = *(volatile __u32 *)p; break;
-        case 8: *(__u64 *)res = *(volatile __u64 *)p; break;
-        default:
-                barrier();
-                __builtin_memcpy((void *)res, (const void *)p, size);
-                barrier();
-        }
+        __READ_ONCE_SIZE;
+}
+
+#ifdef CONFIG_KASAN
+/*
+ * This function is not 'inline' because __no_sanitize_address confilcts
+ * with inlining. Attempt to inline it may cause a build failure.
+ *      https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67368
+ * '__maybe_unused' allows us to avoid defined-but-not-used warnings.
+ */
+static __no_sanitize_address __maybe_unused
+void __read_once_size_nocheck(const volatile void *p, void *res, int size)
+{
+        __READ_ONCE_SIZE;
+}
+#else
+static __always_inline
+void __read_once_size_nocheck(const volatile void *p, void *res, int size)
+{
+        __READ_ONCE_SIZE;
 }
+#endif
 
 static __always_inline void __write_once_size(volatile void *p, void *res, int size)
 {
@@ -248,8 +274,22 @@ static __always_inline void __write_once_size(volatile void *p, void *res, int s
  * required ordering.
  */
 
-#define READ_ONCE(x) \
-        ({ union { typeof(x) __val; char __c[1]; } __u; __read_once_size(&(x), __u.__c, sizeof(x)); __u.__val; })
+#define __READ_ONCE(x, check)                                           \
+({                                                                      \
+        union { typeof(x) __val; char __c[1]; } __u;                    \
+        if (check)                                                      \
+                __read_once_size(&(x), __u.__c, sizeof(x));             \
+        else                                                            \
+                __read_once_size_nocheck(&(x), __u.__c, sizeof(x));     \
+        __u.__val;                                                      \
+})
+#define READ_ONCE(x) __READ_ONCE(x, 1)
+
+/*
+ * Use READ_ONCE_NOCHECK() instead of READ_ONCE() if you need
+ * to hide memory access from KASAN.
+ */
+#define READ_ONCE_NOCHECK(x) __READ_ONCE(x, 0)
 
 #define WRITE_ONCE(x, val) \
 ({                                                      \
diff --git a/include/linux/dma-contiguous.h b/include/linux/dma-contiguous.h
index 569bbd039896..fec734df1524 100644
--- a/include/linux/dma-contiguous.h
+++ b/include/linux/dma-contiguous.h
@@ -111,7 +111,7 @@ static inline int dma_declare_contiguous(struct device *dev, phys_addr_t size,
         return ret;
 }
 
-struct page *dma_alloc_from_contiguous(struct device *dev, int count,
+struct page *dma_alloc_from_contiguous(struct device *dev, size_t count,
                                        unsigned int order);
 bool dma_release_from_contiguous(struct device *dev, struct page *pages,
                                  int count);
@@ -144,7 +144,7 @@ int dma_declare_contiguous(struct device *dev, phys_addr_t size,
 }
 
 static inline
-struct page *dma_alloc_from_contiguous(struct device *dev, int count,
+struct page *dma_alloc_from_contiguous(struct device *dev, size_t count,
                                        unsigned int order)
 {
         return NULL;
diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index 6452ff4c463f..3e3318ddfc0e 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -676,8 +676,9 @@ enum {
 
 struct list_head *mem_cgroup_cgwb_list(struct mem_cgroup *memcg);
 struct wb_domain *mem_cgroup_wb_domain(struct bdi_writeback *wb);
-void mem_cgroup_wb_stats(struct bdi_writeback *wb, unsigned long *pavail,
-                         unsigned long *pdirty, unsigned long *pwriteback);
+void mem_cgroup_wb_stats(struct bdi_writeback *wb, unsigned long *pfilepages,
+                         unsigned long *pheadroom, unsigned long *pdirty,
+                         unsigned long *pwriteback);
 
 #else   /* CONFIG_CGROUP_WRITEBACK */
 
@@ -687,7 +688,8 @@ static inline struct wb_domain *mem_cgroup_wb_domain(struct bdi_writeback *wb)
 }
 
 static inline void mem_cgroup_wb_stats(struct bdi_writeback *wb,
-                                       unsigned long *pavail,
+                                       unsigned long *pfilepages,
+                                       unsigned long *pheadroom,
                                        unsigned long *pdirty,
                                        unsigned long *pwriteback)
 {