The patch modifies the i_version field of the inode on the VFS layer.
The i_version field become a 64bit counter that is set on inode creation and
that is incremented every time the inode data is modified (similarly to the
"ctime" time-stamp).
The aim is to fulfill a NFSv4 requirement for rfc3530:
"5.5. Mandatory Attributes - Definitions
Name # DataType Access Description
___________________________________________________________________
change 3 uint64 READ A value created by the
server that the client can use to determine if file
data, directory contents or attributes of the object
have been modified. The servermay return the object's
time_metadata attribute for this attribute's value but
only if the filesystem object can not be updated more
frequently than the resolution of time_metadata."
Signed-off-by: Jean Noel Cordenner <[email protected]>
Index: linux-2.6.22-rc2-ext4-1/fs/binfmt_misc.c
===================================================================
--- linux-2.6.22-rc2-ext4-1.orig/fs/binfmt_misc.c 2007-05-25 18:01:51.000000000 +0200
+++ linux-2.6.22-rc2-ext4-1/fs/binfmt_misc.c 2007-05-25 18:01:56.000000000 +0200
@@ -508,6 +508,7 @@
inode->i_blocks = 0;
inode->i_atime = inode->i_mtime = inode->i_ctime =
current_fs_time(inode->i_sb);
+ inode->i_version = 1;
}
return inode;
}
Index: linux-2.6.22-rc2-ext4-1/fs/libfs.c
===================================================================
--- linux-2.6.22-rc2-ext4-1.orig/fs/libfs.c 2007-05-25 18:01:51.000000000 +0200
+++ linux-2.6.22-rc2-ext4-1/fs/libfs.c 2007-05-25 18:01:56.000000000 +0200
@@ -232,6 +232,7 @@
root->i_mode = S_IFDIR | S_IRUSR | S_IWUSR;
root->i_uid = root->i_gid = 0;
root->i_atime = root->i_mtime = root->i_ctime = CURRENT_TIME;
+ root->i_version = 1;
dentry = d_alloc(NULL, &d_name);
if (!dentry) {
iput(root);
@@ -255,6 +256,8 @@
struct inode *inode = old_dentry->d_inode;
inode->i_ctime = dir->i_ctime = dir->i_mtime = CURRENT_TIME;
+ inode->i_version++;
+ dir->i_version++;
inc_nlink(inode);
atomic_inc(&inode->i_count);
dget(dentry);
@@ -287,6 +290,8 @@
struct inode *inode = dentry->d_inode;
inode->i_ctime = dir->i_ctime = dir->i_mtime = CURRENT_TIME;
+ inode->i_version++;
+ dir->i_version++;
drop_nlink(inode);
dput(dentry);
return 0;
@@ -323,6 +328,8 @@
old_dir->i_ctime = old_dir->i_mtime = new_dir->i_ctime =
new_dir->i_mtime = inode->i_ctime = CURRENT_TIME;
+ old_dir->i_version++;
+ new_dir->i_version++;
return 0;
}
@@ -399,6 +406,7 @@
inode->i_uid = inode->i_gid = 0;
inode->i_blocks = 0;
inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
+ inode->i_version = 1;
inode->i_op = &simple_dir_inode_operations;
inode->i_fop = &simple_dir_operations;
inode->i_nlink = 2;
@@ -427,6 +435,7 @@
inode->i_uid = inode->i_gid = 0;
inode->i_blocks = 0;
inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
+ inode->i_version = 1;
inode->i_fop = files->ops;
inode->i_ino = i;
d_add(dentry, inode);
Index: linux-2.6.22-rc2-ext4-1/fs/pipe.c
===================================================================
--- linux-2.6.22-rc2-ext4-1.orig/fs/pipe.c 2007-05-25 18:01:51.000000000 +0200
+++ linux-2.6.22-rc2-ext4-1/fs/pipe.c 2007-05-25 18:01:56.000000000 +0200
@@ -882,6 +882,7 @@
inode->i_uid = current->fsuid;
inode->i_gid = current->fsgid;
inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
+ inode->i_version = 1;
return inode;
Index: linux-2.6.22-rc2-ext4-1/include/linux/fs.h
===================================================================
--- linux-2.6.22-rc2-ext4-1.orig/include/linux/fs.h 2007-05-25 18:01:51.000000000 +0200
+++ linux-2.6.22-rc2-ext4-1/include/linux/fs.h 2007-05-25 18:01:56.000000000 +0200
@@ -549,7 +549,7 @@
uid_t i_uid;
gid_t i_gid;
dev_t i_rdev;
- unsigned long i_version;
+ uint64_t i_version;
loff_t i_size;
#ifdef __NEED_I_SIZE_ORDERED
seqcount_t i_size_seqcount;