2 files changed, 32 insertions, 0 deletions

diff --git a/include/linux/shmem_fs.h b/include/linux/shmem_fs.h
index 4d1771c2d29f..50777b5b1e4c 100644
--- a/include/linux/shmem_fs.h
+++ b/include/linux/shmem_fs.h
@@ -1,6 +1,7 @@
 #ifndef __SHMEM_FS_H
 #define __SHMEM_FS_H
 
+#include <linux/file.h>
 #include <linux/swap.h>
 #include <linux/mempolicy.h>
 #include <linux/pagemap.h>
@@ -11,6 +12,7 @@
 
 struct shmem_inode_info {
         spinlock_t              lock;
+        unsigned int            seals;          /* shmem seals */
         unsigned long           flags;
         unsigned long           alloced;        /* data pages alloced to file */
         union {
@@ -65,4 +67,19 @@ static inline struct page *shmem_read_mapping_page(
                                         mapping_gfp_mask(mapping));
 }
 
+#ifdef CONFIG_TMPFS
+
+extern int shmem_add_seals(struct file *file, unsigned int seals);
+extern int shmem_get_seals(struct file *file);
+extern long shmem_fcntl(struct file *file, unsigned int cmd, unsigned long arg);
+
+#else
+
+static inline long shmem_fcntl(struct file *f, unsigned int c, unsigned long a)
+{
+        return -EINVAL;
+}
+
+#endif
+
 #endif
diff --git a/include/uapi/linux/fcntl.h b/include/uapi/linux/fcntl.h
index 074b886c6be0..beed138bd359 100644
--- a/include/uapi/linux/fcntl.h
+++ b/include/uapi/linux/fcntl.h
@@ -28,6 +28,21 @@
 #define F_GETPIPE_SZ    (F_LINUX_SPECIFIC_BASE + 8)
 
 /*
+ * Set/Get seals
+ */
+#define F_ADD_SEALS     (F_LINUX_SPECIFIC_BASE + 9)
+#define F_GET_SEALS     (F_LINUX_SPECIFIC_BASE + 10)
+
+/*
+ * Types of seals
+ */
+#define F_SEAL_SEAL     0x0001  /* prevent further seals from being set */
+#define F_SEAL_SHRINK   0x0002  /* prevent file from shrinking */
+#define F_SEAL_GROW     0x0004  /* prevent file from growing */
+#define F_SEAL_WRITE    0x0008  /* prevent writes */
+/* (1U << 31) is reserved for signed error codes */
+
+/*
  * Types of directory notifications that may be requested.
  */
 #define DN_ACCESS       0x00000001      /* File accessed */