Merge tag 'v4.7-rc2' into v4l_for_linus

Linux 4.7-rc2

* tag 'v4.7-rc2': (10914 commits)
  Linux 4.7-rc2
  devpts: Make each mount of devpts an independent filesystem.
  parisc: Move die_if_kernel() prototype into traps.h header
  parisc: Fix pagefault crash in unaligned __get_user() call
  parisc: Fix printk time during boot
  parisc: Fix backtrace on PA-RISC
  mm, page_alloc: recalculate the preferred zoneref if the context can ignore memory policies
  mm, page_alloc: reset zonelist iterator after resetting fair zone allocation policy
  mm, oom_reaper: do not use siglock in try_oom_reaper()
  mm, page_alloc: prevent infinite loop in buffered_rmqueue()
  checkpatch: reduce git commit description style false positives
  mm/z3fold.c: avoid modifying HEADLESS page and minor cleanup
  memcg: add RCU locking around css_for_each_descendant_pre() in memcg_offline_kmem()
  mm: check the return value of lookup_page_ext for all call sites
  kdump: fix dmesg gdbmacro to work with record based printk
  mm: fix overflow in vm_map_ram()
  Btrfs: deal with duplciates during extent_map insertion in btrfs_get_extent
  arm64: fix alignment when RANDOMIZE_TEXT_OFFSET is enabled
  arm64: move {PAGE,CONT}_SHIFT into Kconfig
  arm64: mm: dump: log span level
  ...

1 files changed, 46 insertions, 3 deletions

diff --git a/include/linux/debugfs.h b/include/linux/debugfs.h
index 981e53ab84e8..1438e2322d5c 100644
--- a/include/linux/debugfs.h
+++ b/include/linux/debugfs.h
@@ -19,9 +19,11 @@
 #include <linux/seq_file.h>
 
 #include <linux/types.h>
+#include <linux/compiler.h>
 
 struct device;
 struct file_operations;
+struct srcu_struct;
 
 struct debugfs_blob_wrapper {
 	void *data;
@@ -41,14 +43,16 @@ struct debugfs_regset32 {
 
 extern struct dentry *arch_debugfs_dir;
 
-#if defined(CONFIG_DEBUG_FS)
+extern struct srcu_struct debugfs_srcu;
 
-/* declared over in file.c */
-extern const struct file_operations debugfs_file_operations;
+#if defined(CONFIG_DEBUG_FS)
 
 struct dentry *debugfs_create_file(const char *name, umode_t mode,
 				   struct dentry *parent, void *data,
 				   const struct file_operations *fops);
+struct dentry *debugfs_create_file_unsafe(const char *name, umode_t mode,
+				   struct dentry *parent, void *data,
+				   const struct file_operations *fops);
 
 struct dentry *debugfs_create_file_size(const char *name, umode_t mode,
 					struct dentry *parent, void *data,
@@ -68,6 +72,31 @@ struct dentry *debugfs_create_automount(const char *name,
 void debugfs_remove(struct dentry *dentry);
 void debugfs_remove_recursive(struct dentry *dentry);
 
+int debugfs_use_file_start(const struct dentry *dentry, int *srcu_idx)
+	__acquires(&debugfs_srcu);
+
+void debugfs_use_file_finish(int srcu_idx) __releases(&debugfs_srcu);
+
+ssize_t debugfs_attr_read(struct file *file, char __user *buf,
+			size_t len, loff_t *ppos);
+ssize_t debugfs_attr_write(struct file *file, const char __user *buf,
+			size_t len, loff_t *ppos);
+
+#define DEFINE_DEBUGFS_ATTRIBUTE(__fops, __get, __set, __fmt)		\
+static int __fops ## _open(struct inode *inode, struct file *file)	\
+{									\
+	__simple_attr_check_format(__fmt, 0ull);			\
+	return simple_attr_open(inode, file, __get, __set, __fmt);	\
+}									\
+static const struct file_operations __fops = {				\
+	.owner	 = THIS_MODULE,					\
+	.open	 = __fops ## _open,					\
+	.release = simple_attr_release,				\
+	.read	 = debugfs_attr_read,					\
+	.write	 = debugfs_attr_write,					\
+	.llseek  = generic_file_llseek,				\
+}
+
 struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry,
                 struct dentry *new_dir, const char *new_name);
 
@@ -176,6 +205,20 @@ static inline void debugfs_remove(struct dentry *dentry)
 static inline void debugfs_remove_recursive(struct dentry *dentry)
 { }
 
+static inline int debugfs_use_file_start(const struct dentry *dentry,
+					int *srcu_idx)
+	__acquires(&debugfs_srcu)
+{
+	return 0;
+}
+
+static inline void debugfs_use_file_finish(int srcu_idx)
+	__releases(&debugfs_srcu)
+{ }
+
+#define DEFINE_DEBUGFS_ATTRIBUTE(__fops, __get, __set, __fmt)	\
+	static const struct file_operations __fops = { 0 }
+
 static inline struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry,
                 struct dentry *new_dir, char *new_name)
 {