[RFC] [patch 3/3] i_version update for ext4: user interface

This patch adds a  ``st_i_version'' field in the stat
structure, and modifies the stat(2) syscall accordingly. Currently the
change is only visible on i386 and x86_64 archs.

Signed-off-by: Jean Noel Cordenner <jean-noel.cordenner@bull.net>
---

 fs/stat.c                 |    3 +++
 include/asm-i386/stat.h   |    4 ++--
 include/asm-x86_64/stat.h |    5 +++--
 include/linux/stat.h      |    1 +
 4 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/fs/stat.c b/fs/stat.c
index 38a8cb2..805aeae 100644
--- a/fs/stat.c
+++ b/fs/stat.c
@@ -31,6 +31,7 @@ void generic_fillattr(struct inode *inode, struct kstat *stat)
 	stat->atime = inode->i_atime;
 	stat->mtime = inode->i_mtime;
 	stat->ctime = inode->i_ctime;
+       stat->i_version = inode->i_version;
 	stat->size = i_size_read(inode);
 	stat->blocks = inode->i_blocks;
 	stat->blksize = (1 << inode->i_blkbits);
@@ -230,6 +231,7 @@ static int cp_new_stat(struct kstat *stat, struct stat __user *statbuf)
 	tmp.st_atime_nsec = stat->atime.tv_nsec;
 	tmp.st_mtime_nsec = stat->mtime.tv_nsec;
 	tmp.st_ctime_nsec = stat->ctime.tv_nsec;
+	tmp.st_i_version = stat->i_version;
 #endif
 	tmp.st_blocks = stat->blocks;
 	tmp.st_blksize = stat->blksize;
@@ -359,6 +361,7 @@ static long cp_new_stat64(struct kstat *stat, struct stat64 __user *statbuf)
 	tmp.st_mtime_nsec = stat->mtime.tv_nsec;
 	tmp.st_ctime = stat->ctime.tv_sec;
 	tmp.st_ctime_nsec = stat->ctime.tv_nsec;
+       tmp.st_i_version = stat->i_version;
 	tmp.st_size = stat->size;
 	tmp.st_blocks = stat->blocks;
 	tmp.st_blksize = stat->blksize;
diff --git a/include/asm-i386/stat.h b/include/asm-i386/stat.h
index 67eae78..edf2f50 100644
--- a/include/asm-i386/stat.h
+++ b/include/asm-i386/stat.h
@@ -32,7 +32,7 @@ struct stat {
 	unsigned long  st_mtime_nsec;
 	unsigned long  st_ctime;
 	unsigned long  st_ctime_nsec;
-	unsigned long  __unused4;
+       unsigned long  st_i_version;
 	unsigned long  __unused5;
 };
 
@@ -41,7 +41,7 @@ struct stat {
  */
 struct stat64 {
 	unsigned long long	st_dev;
-	unsigned char	__pad0[4];
+       unsigned int    st_i_version;
 
 #define STAT64_HAS_BROKEN_ST_INO	1
 	unsigned long	__st_ino;
diff --git a/include/asm-x86_64/stat.h b/include/asm-x86_64/stat.h
index fd9f00d..35ab36a 100644
--- a/include/asm-x86_64/stat.h
+++ b/include/asm-x86_64/stat.h
@@ -22,8 +22,9 @@ struct stat {
 	unsigned long	st_mtime;
 	unsigned long	st_mtime_nsec;
 	unsigned long	st_ctime;
-	unsigned long   st_ctime_nsec;
-  	long		__unused[3];
+	unsigned long	st_ctime_nsec;
+	unsigned long	st_i_version;
+	long		__unused[2];
 };
 
 /* For 32bit emulation */
diff --git a/include/linux/stat.h b/include/linux/stat.h
index 679ef0d..264f4d3 100644
--- a/include/linux/stat.h
+++ b/include/linux/stat.h
@@ -68,6 +68,7 @@ struct kstat {
 	struct timespec  atime;
 	struct timespec	mtime;
 	struct timespec	ctime;
+       unsigned long   i_version;
 	unsigned long	blksize;
 	unsigned long long	blocks;
 };