f2fs: add F2FS_IOC_GETVERSION support

In this patch we add the FS_IOC_GETVERSION ioctl for getting i_generation from
inode, after that, users can list file's generation number by using "lsattr -v".

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

2 files changed, 10 insertions, 0 deletions

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 1795ce231118..5e16085d98d3 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -202,6 +202,7 @@ static inline bool __has_cursum_space(struct f2fs_summary_block *sum, int size,
  */
 #define F2FS_IOC_GETFLAGS               FS_IOC_GETFLAGS
 #define F2FS_IOC_SETFLAGS               FS_IOC_SETFLAGS
+#define F2FS_IOC_GETVERSION             FS_IOC_GETVERSION
 
 #define F2FS_IOCTL_MAGIC                0xf5
 #define F2FS_IOC_START_ATOMIC_WRITE     _IO(F2FS_IOCTL_MAGIC, 1)
diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index 710adc987937..ec17d05d6553 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -926,6 +926,13 @@ out:
         return ret;
 }
 
+static int f2fs_ioc_getversion(struct file *filp, unsigned long arg)
+{
+        struct inode *inode = file_inode(filp);
+
+        return put_user(inode->i_generation, (int __user *)arg);
+}
+
 static int f2fs_ioc_start_atomic_write(struct file *filp)
 {
         struct inode *inode = file_inode(filp);
@@ -1061,6 +1068,8 @@ long f2fs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
                 return f2fs_ioc_getflags(filp, arg);
         case F2FS_IOC_SETFLAGS:
                 return f2fs_ioc_setflags(filp, arg);
+        case F2FS_IOC_GETVERSION:
+                return f2fs_ioc_getversion(filp, arg);
         case F2FS_IOC_START_ATOMIC_WRITE:
                 return f2fs_ioc_start_atomic_write(filp);
         case F2FS_IOC_COMMIT_ATOMIC_WRITE: