On Thu, Sep 25, 2014 at 1:11 AM, Jan Kara [off-list ref] wrote:

On Wed 24-09-14 22:04:28, Li Xi wrote:

quoted

This patch adds a new internal field of ext4 inode to save project
identifier. Also a new flag EXT4_INODE_PROJINHERIT is added for
inheriting project ID from parent directory.

  Nice. Just a few smaller things below.

  Firstly, I think your patch forgets to add a check to EXT4_IOC_SETFLAGS
ioctl so that EXT4_INODE_PROJINHERIT flag can be set only when
EXT4_FEATURE_RO_COMPAT_PROJECT is enabled.

PROJINHERIT is a flag which affects the project ID inheriting. Is there
any special reason that this flag can be set/cleared only if
EXT4_FEATURE_RO_COMPAT_PROJECT is enabled? We don't check
that feature even when set/get project ID now, so I am not so sure
that this is consistent.

quoted

Signed-off-by: Li Xi <redacted>
---
 fs/ext4/ext4.h   |   21 +++++++++++++++++----
 fs/ext4/ialloc.c |    6 ++++++
 fs/ext4/inode.c  |   29 ++++++++++++++++++++++++++++-
 fs/ext4/namei.c  |   10 ++++++++++
 fs/ext4/super.c  |    1 +
 5 files changed, 62 insertions(+), 5 deletions(-)

...

quoted

diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c
index 5b87fc3..b6b7284 100644
--- a/fs/ext4/ialloc.c
+++ b/fs/ext4/ialloc.c

@@ -756,6 +756,12 @@ struct inode *__ext4_new_inode(handle_t *handle, struct inode *dir,
              inode->i_gid = dir->i_gid;
      } else
              inode_init_owner(inode, dir, mode);
+     if (ext4_test_inode_flag(dir, EXT4_INODE_PROJINHERIT)) {
+             ei->i_projid = EXT4_I(dir)->i_projid;
+     } else {
+             ei->i_projid =
+                     make_kprojid(&init_user_ns, EXT4_DEF_PROJID);
+     }
      dquot_initialize(inode);

      if (!goal)

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index d5dd7d4..8c641eb 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c

@@ -3874,6 +3874,24 @@ static inline void ext4_iget_extra_inode(struct inode *inode,
              EXT4_I(inode)->i_inline_off = 0;
 }

+static projid_t ext4_inode_projid_get(struct inode *inode, struct ext4_inode *raw,
+                              struct ext4_inode_info *ei)
+{
+     return (projid_t)le32_to_cpu(raw->i_projid);
+}
+
+static void ext4_inode_projid_set(struct inode *inode, struct ext4_inode *raw,
+                              struct ext4_inode_info *ei, projid_t projid)
+{
+     raw->i_projid = cpu_to_le32(projid);
+}

  I don't see a need for these two wrappers. IMHO they just obfuscate the
code. Please just write the code directly in appropriate place.

Sure.

quoted

@@ -4204,7 +4228,8 @@ static int ext4_do_update_inode(handle_t *handle,
      EXT4_INODE_SET_XTIME(i_atime, inode, raw_inode);
      EXT4_EINODE_SET_XTIME(i_crtime, ei, raw_inode);

-     if (ext4_inode_blocks_set(handle, raw_inode, ei)) {
+     err = ext4_inode_blocks_set(handle, raw_inode, ei);
+     if (err) {
              spin_unlock(&ei->i_raw_lock);
              goto out_brelse;
      }

  This is an unrelated fix, right? Please send as a separate patch. Thanks!

No problem!

quoted

@@ -4255,6 +4280,8 @@ static int ext4_do_update_inode(handle_t *handle,

      ext4_inode_csum_set(inode, raw_inode, ei);

+     ext4_inode_projid_set(inode, raw_inode, ei, i_projid);
+

  This is wrong - you have to set project ID before a checksum is computed.

Yeah, sorry for this mistake.

Regards,
                                     - Li Xi