inode-version-vfs.patch

   1 VFS: Add 64 bit inode version support
   2
   3 From: Jean Noel Cordenner <jean-noel.cordenner@bull.net>
   4
   5 The i_version field of the inode is changed to be a 64-bit counter that
   6 is set on every inode creation and that is incremented every time the
   7 inode data is modified (similarly to the "ctime" time-stamp).
   8 The aim is to fulfill a NFSv4 requirement for rfc3530.
   9 This first part concerns the vfs, it converts the 32-bit i_version in
  10 the generic inode to a 64-bit, a flag is added in the super block in
  11 order to check if the feature is enabled and the i_version is
  12 incremented in the vfs.
  13
  14 Signed-off-by: Mingming Cao <cmm@us.ibm.com>
  15 Signed-off-by: Jean Noel Cordenner <jean-noel.cordenner@bull.net>
  16 Signed-off-by: Kalpak Shah <kalpak@clusterfs.com>
  17 ---
  18  fs/inode.c         |   22 ++++++++++++++++++++++
  19  include/linux/fs.h |    5 ++++-
  20  2 files changed, 26 insertions(+), 1 deletion(-)
  21
  22 Index: linux-2.6.24-rc3/include/linux/fs.h
  23 ===================================================================
  24 --- linux-2.6.24-rc3.orig/include/linux/fs.h    2007-11-20 17:11:39.000000000 -0800
  25 +++ linux-2.6.24-rc3/include/linux/fs.h 2007-11-20 17:15:24.000000000 -0800
  26 @@ -124,6 +124,7 @@ extern int dir_notify_enable;
  27  #define MS_SHARED      (1<<20) /* change to shared */
  28  #define MS_RELATIME    (1<<21) /* Update atime relative to mtime/ctime. */
  29  #define MS_KERNMOUNT   (1<<22) /* this is a kern_mount call */
  30 +#define MS_I_VERSION   (1<<23) /* Update inode I_version field */
  31  #define MS_ACTIVE      (1<<30)
  32  #define MS_NOUSER      (1<<31)
  33
  34 @@ -173,6 +174,7 @@ extern int dir_notify_enable;
  35                                         ((inode)->i_flags & (S_SYNC|S_DIRSYNC)))
  36  #define IS_MANDLOCK(inode)     __IS_FLG(inode, MS_MANDLOCK)
  37  #define IS_NOATIME(inode)   __IS_FLG(inode, MS_RDONLY|MS_NOATIME)
  38 +#define IS_I_VERSION(inode)   __IS_FLG(inode, MS_I_VERSION)
  39
  40  #define IS_NOQUOTA(inode)      ((inode)->i_flags & S_NOQUOTA)
  41  #define IS_APPEND(inode)       ((inode)->i_flags & S_APPEND)
  42 @@ -599,7 +601,7 @@ struct inode {
  43         uid_t                   i_uid;
  44         gid_t                   i_gid;
  45         dev_t                   i_rdev;
  46 -       unsigned long           i_version;
  47 +       u64                     i_version;
  48         loff_t                  i_size;
  49  #ifdef __NEED_I_SIZE_ORDERED
  50         seqcount_t              i_size_seqcount;
  51 @@ -1394,6 +1396,7 @@ static inline void inode_dec_link_count(
  52         mark_inode_dirty(inode);
  53  }
  54
  55 +extern void inode_inc_iversion(struct inode *inode);
  56  extern void touch_atime(struct vfsmount *mnt, struct dentry *dentry);
  57  static inline void file_accessed(struct file *file)
  58  {
  59 Index: linux-2.6.24-rc3/fs/inode.c
  60 ===================================================================
  61 --- linux-2.6.24-rc3.orig/fs/inode.c    2007-11-16 21:16:36.000000000 -0800
  62 +++ linux-2.6.24-rc3/fs/inode.c 2007-11-20 17:12:52.000000000 -0800
  63 @@ -1243,6 +1243,23 @@ void touch_atime(struct vfsmount *mnt, s
  64  EXPORT_SYMBOL(touch_atime);
  65
  66  /**
  67 + *     inode_inc_iversion      -       increments i_version
  68 + *     @inode: inode that need to be updated
  69 + *
  70 + *     Every time the inode is modified, the i_version field
  71 + *     will be incremented.
  72 + *     The filesystem has to be mounted with i_version flag
  73 + *
  74 + */
  75 +
  76 +void inode_inc_iversion(struct inode *inode)
  77 +{
  78 +       spin_lock(&inode->i_lock);
  79 +       inode->i_version++;
  80 +       spin_unlock(&inode->i_lock);
  81 +}
  82 +
  83 +/**
  84   *     file_update_time        -       update mtime and ctime time
  85   *     @file: file accessed
  86   *
  87 @@ -1276,6 +1293,11 @@ void file_update_time(struct file *file)
  88                 sync_it = 1;
  89         }
  90
  91 +       if (IS_I_VERSION(inode)) {
  92 +               inode_inc_iversion(inode);
  93 +               sync_it = 1;
  94 +       }
  95 +
  96         if (sync_it)
  97                 mark_inode_dirty_sync(inode);
  98  }