ext4: adds project ID support

Signed-off-by: Li Xi <lixi@ddn.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Reviewed-by: Jan Kara <jack@suse.cz>

1 files changed, 28 insertions, 0 deletions

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index ff2f3cd38522..6770c07ab39f 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -4193,6 +4193,14 @@ static inline void ext4_iget_extra_inode(struct inode *inode,
                 EXT4_I(inode)->i_inline_off = 0;
 }
 
+int ext4_get_projid(struct inode *inode, kprojid_t *projid)
+{
+        if (!EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb, EXT4_FEATURE_RO_COMPAT_PROJECT))
+                return -EOPNOTSUPP;
+        *projid = EXT4_I(inode)->i_projid;
+        return 0;
+}
+
 struct inode *ext4_iget(struct super_block *sb, unsigned long ino)
 {
         struct ext4_iloc iloc;
@@ -4204,6 +4212,7 @@ struct inode *ext4_iget(struct super_block *sb, unsigned long ino)
         int block;
         uid_t i_uid;
         gid_t i_gid;
+        projid_t i_projid;
 
         inode = iget_locked(sb, ino);
         if (!inode)
@@ -4253,12 +4262,20 @@ struct inode *ext4_iget(struct super_block *sb, unsigned long ino)
         inode->i_mode = le16_to_cpu(raw_inode->i_mode);
         i_uid = (uid_t)le16_to_cpu(raw_inode->i_uid_low);
         i_gid = (gid_t)le16_to_cpu(raw_inode->i_gid_low);
+        if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_PROJECT) &&
+            EXT4_INODE_SIZE(sb) > EXT4_GOOD_OLD_INODE_SIZE &&
+            EXT4_FITS_IN_INODE(raw_inode, ei, i_projid))
+                i_projid = (projid_t)le32_to_cpu(raw_inode->i_projid);
+        else
+                i_projid = EXT4_DEF_PROJID;
+
         if (!(test_opt(inode->i_sb, NO_UID32))) {
                 i_uid |= le16_to_cpu(raw_inode->i_uid_high) << 16;
                 i_gid |= le16_to_cpu(raw_inode->i_gid_high) << 16;
         }
         i_uid_write(inode, i_uid);
         i_gid_write(inode, i_gid);
+        ei->i_projid = make_kprojid(&init_user_ns, i_projid);
         set_nlink(inode, le16_to_cpu(raw_inode->i_links_count));
 
         ext4_clear_state_flags(ei);     /* Only relevant on 32-bit archs */
@@ -4556,6 +4573,7 @@ static int ext4_do_update_inode(handle_t *handle,
         int need_datasync = 0, set_large_file = 0;
         uid_t i_uid;
         gid_t i_gid;
+        projid_t i_projid;
 
         spin_lock(&ei->i_raw_lock);
 
@@ -4568,6 +4586,7 @@ static int ext4_do_update_inode(handle_t *handle,
         raw_inode->i_mode = cpu_to_le16(inode->i_mode);
         i_uid = i_uid_read(inode);
         i_gid = i_gid_read(inode);
+        i_projid = from_kprojid(&init_user_ns, ei->i_projid);
         if (!(test_opt(inode->i_sb, NO_UID32))) {
                 raw_inode->i_uid_low = cpu_to_le16(low_16_bits(i_uid));
                 raw_inode->i_gid_low = cpu_to_le16(low_16_bits(i_gid));
@@ -4645,6 +4664,15 @@ static int ext4_do_update_inode(handle_t *handle,
                                 cpu_to_le16(ei->i_extra_isize);
                 }
         }
+
+        BUG_ON(!EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
+                        EXT4_FEATURE_RO_COMPAT_PROJECT) &&
+               i_projid != EXT4_DEF_PROJID);
+
+        if (EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE &&
+            EXT4_FITS_IN_INODE(raw_inode, ei, i_projid))
+                raw_inode->i_projid = cpu_to_le32(i_projid);
+
         ext4_inode_csum_set(inode, raw_inode, ei);
         spin_unlock(&ei->i_raw_lock);
         if (inode->i_sb->s_flags & MS_LAZYTIME)