Btrfs: Add code to support file creation time

This patch adds a new member to the 'struct btrfs_inode' structure to hold
the file creation time.

Signed-off-by: chandan <chandanrmail@gmail.com>
[refreshed, removed btrfs_inode_otime]
Signed-off-by: David Sterba <dsterba@suse.cz>

Signed-off-by: Chris Mason <clm@fb.com>

3 files changed, 36 insertions, 2 deletions

diff --git a/fs/btrfs/btrfs_inode.h b/fs/btrfs/btrfs_inode.h
index 4aadadcfab20..de5e4f2adfea 100644
--- a/fs/btrfs/btrfs_inode.h
+++ b/fs/btrfs/btrfs_inode.h
@@ -185,6 +185,9 @@ struct btrfs_inode {
 
         struct btrfs_delayed_node *delayed_node;
 
+        /* File creation time. */
+        struct timespec i_otime;
+
         struct inode vfs_inode;
 };
 
diff --git a/fs/btrfs/delayed-inode.c b/fs/btrfs/delayed-inode.c
index 116eb4bed8d3..82f0c7c95474 100644
--- a/fs/btrfs/delayed-inode.c
+++ b/fs/btrfs/delayed-inode.c
@@ -1769,6 +1769,11 @@ static void fill_stack_inode_item(struct btrfs_trans_handle *trans,
                                      inode->i_ctime.tv_sec);
         btrfs_set_stack_timespec_nsec(&inode_item->ctime,
                                       inode->i_ctime.tv_nsec);
+
+        btrfs_set_stack_timespec_sec(&inode_item->otime,
+                                     BTRFS_I(inode)->i_otime.tv_sec);
+        btrfs_set_stack_timespec_nsec(&inode_item->otime,
+                                     BTRFS_I(inode)->i_otime.tv_nsec);
 }
 
 int btrfs_fill_inode(struct inode *inode, u32 *rdev)
@@ -1810,6 +1815,11 @@ int btrfs_fill_inode(struct inode *inode, u32 *rdev)
         inode->i_ctime.tv_sec = btrfs_stack_timespec_sec(&inode_item->ctime);
         inode->i_ctime.tv_nsec = btrfs_stack_timespec_nsec(&inode_item->ctime);
 
+        BTRFS_I(inode)->i_otime.tv_sec =
+                btrfs_stack_timespec_sec(&inode_item->otime);
+        BTRFS_I(inode)->i_otime.tv_nsec =
+                btrfs_stack_timespec_nsec(&inode_item->otime);
+
         inode->i_generation = BTRFS_I(inode)->generation;
         BTRFS_I(inode)->index_cnt = (u64)-1;
 
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 575164d802af..b0292333fd84 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -3535,6 +3535,11 @@ static void btrfs_read_locked_inode(struct inode *inode)
         inode->i_ctime.tv_sec = btrfs_timespec_sec(leaf, &inode_item->ctime);
         inode->i_ctime.tv_nsec = btrfs_timespec_nsec(leaf, &inode_item->ctime);
 
+        BTRFS_I(inode)->i_otime.tv_sec =
+                btrfs_timespec_sec(leaf, &inode_item->otime);
+        BTRFS_I(inode)->i_otime.tv_nsec =
+                btrfs_timespec_nsec(leaf, &inode_item->otime);
+
         inode_set_bytes(inode, btrfs_inode_nbytes(leaf, inode_item));
         BTRFS_I(inode)->generation = btrfs_inode_generation(leaf, inode_item);
         BTRFS_I(inode)->last_trans = btrfs_inode_transid(leaf, inode_item);
@@ -3669,6 +3674,11 @@ static void fill_inode_item(struct btrfs_trans_handle *trans,
         btrfs_set_token_timespec_nsec(leaf, &item->ctime,
                                       inode->i_ctime.tv_nsec, &token);
 
+        btrfs_set_token_timespec_sec(leaf, &item->otime,
+                                     BTRFS_I(inode)->i_otime.tv_sec, &token);
+        btrfs_set_token_timespec_nsec(leaf, &item->otime,
+                                      BTRFS_I(inode)->i_otime.tv_nsec, &token);
+
         btrfs_set_token_inode_nbytes(leaf, item, inode_get_bytes(inode),
                                      &token);
         btrfs_set_token_inode_generation(leaf, item, BTRFS_I(inode)->generation,
@@ -5260,7 +5270,10 @@ static struct inode *new_simple_dir(struct super_block *s,
         inode->i_op = &btrfs_dir_ro_inode_operations;
         inode->i_fop = &simple_dir_operations;
         inode->i_mode = S_IFDIR | S_IRUGO | S_IWUSR | S_IXUGO;
-        inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
+        inode->i_mtime = CURRENT_TIME;
+        inode->i_atime = inode->i_mtime;
+        inode->i_ctime = inode->i_mtime;
+        BTRFS_I(inode)->i_otime = inode->i_mtime;
 
         return inode;
 }
@@ -5828,7 +5841,12 @@ static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
 
         inode_init_owner(inode, dir, mode);
         inode_set_bytes(inode, 0);
-        inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
+
+        inode->i_mtime = CURRENT_TIME;
+        inode->i_atime = inode->i_mtime;
+        inode->i_ctime = inode->i_mtime;
+        BTRFS_I(inode)->i_otime = inode->i_mtime;
+
         inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
                                   struct btrfs_inode_item);
         memset_extent_buffer(path->nodes[0], 0, (unsigned long)inode_item,
@@ -8577,6 +8595,9 @@ struct inode *btrfs_alloc_inode(struct super_block *sb)
 
         ei->delayed_node = NULL;
 
+        ei->i_otime.tv_sec = 0;
+        ei->i_otime.tv_nsec = 0;
+
         inode = &ei->vfs_inode;
         extent_map_tree_init(&ei->extent_tree);
         extent_io_tree_init(&ei->io_tree, &inode->i_data);