vfs: Add 64 bit i_version support

The i_version field of the inode is changed to be a 64-bit counter that
is set on every 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.
This first part concerns the vfs, it converts the 32-bit i_version in
the generic inode to a 64-bit, a flag is added in the super block in
order to check if the feature is enabled and the i_version is
incremented in the vfs.

Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: Jean Noel Cordenner <jean-noel.cordenner@bull.net>
Signed-off-by: Kalpak Shah <kalpak@clusterfs.com>

diff --git a/fs/afs/dir.c b/fs/afs/dir.c
index 33fe39a..0cc3597 100644 (file)
--- a/fs/afs/dir.c
+++ b/fs/afs/dir.c
@@ -546,11 +546,11 @@ static struct dentry *afs_lookup(struct inode *dir, struct dentry *dentry,
        dentry->d_op = &afs_fs_dentry_operations;
 
        d_add(dentry, inode);
-       _leave(" = 0 { vn=%u u=%u } -> { ino=%lu v=%lu }",
+       _leave(" = 0 { vn=%u u=%u } -> { ino=%lu v=%llu }",
               fid.vnode,
               fid.unique,
               dentry->d_inode->i_ino,
-              dentry->d_inode->i_version);
+              (unsigned long long)dentry->d_inode->i_version);
 
        return NULL;
 }
@@ -630,9 +630,10 @@ static int afs_d_revalidate(struct dentry *dentry, struct nameidata *nd)
                 * been deleted and replaced, and the original vnode ID has
                 * been reused */
                if (fid.unique != vnode->fid.unique) {
-                       _debug("%s: file deleted (uq %u -> %u I:%lu)",
+                       _debug("%s: file deleted (uq %u -> %u I:%llu)",
                               dentry->d_name.name, fid.unique,
-                              vnode->fid.unique, dentry->d_inode->i_version);
+                              vnode->fid.unique,
+                              (unsigned long long)dentry->d_inode->i_version);
                        spin_lock(&vnode->lock);
                        set_bit(AFS_VNODE_DELETED, &vnode->flags);
                        spin_unlock(&vnode->lock);

diff --git a/fs/afs/inode.c b/fs/afs/inode.c
index d196840..84750c8 100644 (file)
--- a/fs/afs/inode.c
+++ b/fs/afs/inode.c
@@ -301,7 +301,8 @@ int afs_getattr(struct vfsmount *mnt, struct dentry *dentry,
 
        inode = dentry->d_inode;
 
-       _enter("{ ino=%lu v=%lu }", inode->i_ino, inode->i_version);
+       _enter("{ ino=%lu v=%llu }", inode->i_ino,
+               (unsigned long long)inode->i_version);
 
        generic_fillattr(inode, stat);
        return 0;

diff --git a/fs/inode.c b/fs/inode.c
index ed35383..b48324a 100644 (file)
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -1243,6 +1243,23 @@ void touch_atime(struct vfsmount *mnt, struct dentry *dentry)
 EXPORT_SYMBOL(touch_atime);
 
 /**
+ *     inode_inc_iversion      -       increments i_version
+ *     @inode: inode that need to be updated
+ *
+ *     Every time the inode is modified, the i_version field
+ *     will be incremented.
+ *     The filesystem has to be mounted with i_version flag
+ *
+ */
+
+void inode_inc_iversion(struct inode *inode)
+{
+       spin_lock(&inode->i_lock);
+       inode->i_version++;
+       spin_unlock(&inode->i_lock);
+}
+
+/**
  *     file_update_time        -       update mtime and ctime time
  *     @file: file accessed
  *
@@ -1276,6 +1293,11 @@ void file_update_time(struct file *file)
                sync_it = 1;
        }
 
+       if (IS_I_VERSION(inode)) {
+               inode_inc_iversion(inode);
+               sync_it = 1;
+       }
+
        if (sync_it)
                mark_inode_dirty_sync(inode);
 }

diff --git a/include/linux/fs.h b/include/linux/fs.h
index 21398a5..9608839 100644 (file)
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -124,6 +124,7 @@ extern int dir_notify_enable;
 #define MS_SHARED      (1<<20) /* change to shared */
 #define MS_RELATIME    (1<<21) /* Update atime relative to mtime/ctime. */
 #define MS_KERNMOUNT   (1<<22) /* this is a kern_mount call */
+#define MS_I_VERSION   (1<<23) /* Update inode I_version field */
 #define MS_ACTIVE      (1<<30)
 #define MS_NOUSER      (1<<31)
 
@@ -173,6 +174,7 @@ extern int dir_notify_enable;
                                        ((inode)->i_flags & (S_SYNC|S_DIRSYNC)))
 #define IS_MANDLOCK(inode)     __IS_FLG(inode, MS_MANDLOCK)
 #define IS_NOATIME(inode)   __IS_FLG(inode, MS_RDONLY|MS_NOATIME)
+#define IS_I_VERSION(inode)   __IS_FLG(inode, MS_I_VERSION)
 
 #define IS_NOQUOTA(inode)      ((inode)->i_flags & S_NOQUOTA)
 #define IS_APPEND(inode)       ((inode)->i_flags & S_APPEND)
@@ -599,7 +601,7 @@ struct inode {
        uid_t                   i_uid;
        gid_t                   i_gid;
        dev_t                   i_rdev;
-       unsigned long           i_version;
+       u64                     i_version;
        loff_t                  i_size;
 #ifdef __NEED_I_SIZE_ORDERED
        seqcount_t              i_size_seqcount;
@@ -1394,6 +1396,7 @@ static inline void inode_dec_link_count(struct inode *inode)
        mark_inode_dirty(inode);
 }
 
+extern void inode_inc_iversion(struct inode *inode);
 extern void touch_atime(struct vfsmount *mnt, struct dentry *dentry);
 static inline void file_accessed(struct file *file)
 {