ovl: respect FIEMAP_FLAG_SYNC flag

[linux.git] / fs / overlayfs / inode.c

diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c
index e46f26ee6e21d42ccc31d22fc6ab61bcf719c69a..5014749fd4b45d346f9c3d4f13495814437cf3d2 100644 (file)
--- a/fs/overlayfs/inode.c
+++ b/fs/overlayfs/inode.c
@@ -19,6 +19,7 @@
 int ovl_setattr(struct dentry *dentry, struct iattr *attr)
 {
        int err;
+       bool full_copy_up = false;
        struct dentry *upperdentry;
        const struct cred *old_cred;
 
@@ -36,9 +37,15 @@ int ovl_setattr(struct dentry *dentry, struct iattr *attr)
                err = -ETXTBSY;
                if (atomic_read(&realinode->i_writecount) < 0)
                        goto out_drop_write;
+
+               /* Truncate should trigger data copy up as well */
+               full_copy_up = true;
        }
 
-       err = ovl_copy_up(dentry);
+       if (!full_copy_up)
+               err = ovl_copy_up(dentry);
+       else
+               err = ovl_copy_up_with_data(dentry);
        if (!err) {
                struct inode *winode = NULL;
 
@@ -145,6 +152,9 @@ int ovl_getattr(const struct path *path, struct kstat *stat,
        bool samefs = ovl_same_sb(dentry->d_sb);
        struct ovl_layer *lower_layer = NULL;
        int err;
+       bool metacopy_blocks = false;
+
+       metacopy_blocks = ovl_is_metacopy_dentry(dentry);
 
        type = ovl_path_real(dentry, &realpath);
        old_cred = ovl_override_creds(dentry->d_sb);
@@ -166,7 +176,8 @@ int ovl_getattr(const struct path *path, struct kstat *stat,
                        lower_layer = ovl_layer_lower(dentry);
                } else if (OVL_TYPE_ORIGIN(type)) {
                        struct kstat lowerstat;
-                       u32 lowermask = STATX_INO | (!is_dir ? STATX_NLINK : 0);
+                       u32 lowermask = STATX_INO | STATX_BLOCKS |
+                                       (!is_dir ? STATX_NLINK : 0);
 
                        ovl_path_lower(dentry, &realpath);
                        err = vfs_getattr(&realpath, &lowerstat,
@@ -195,6 +206,35 @@ int ovl_getattr(const struct path *path, struct kstat *stat,
                                stat->ino = lowerstat.ino;
                                lower_layer = ovl_layer_lower(dentry);
                        }
+
+                       /*
+                        * If we are querying a metacopy dentry and lower
+                        * dentry is data dentry, then use the blocks we
+                        * queried just now. We don't have to do additional
+                        * vfs_getattr(). If lower itself is metacopy, then
+                        * additional vfs_getattr() is unavoidable.
+                        */
+                       if (metacopy_blocks &&
+                           realpath.dentry == ovl_dentry_lowerdata(dentry)) {
+                               stat->blocks = lowerstat.blocks;
+                               metacopy_blocks = false;
+                       }
+               }
+
+               if (metacopy_blocks) {
+                       /*
+                        * If lower is not same as lowerdata or if there was
+                        * no origin on upper, we can end up here.
+                        */
+                       struct kstat lowerdatastat;
+                       u32 lowermask = STATX_BLOCKS;
+
+                       ovl_path_lowerdata(dentry, &realpath);
+                       err = vfs_getattr(&realpath, &lowerdatastat,
+                                         lowermask, flags);
+                       if (err)
+                               goto out;
+                       stat->blocks = lowerdatastat.blocks;
                }
        }
 
@@ -427,6 +467,10 @@ static int ovl_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
                return -EOPNOTSUPP;
 
        old_cred = ovl_override_creds(inode->i_sb);
+
+       if (fieinfo->fi_flags & FIEMAP_FLAG_SYNC)
+               filemap_write_and_wait(realinode->i_mapping);
+
        err = realinode->i_op->fiemap(realinode, fieinfo, start, len);
        revert_creds(old_cred);
 
@@ -780,7 +824,7 @@ struct inode *ovl_get_inode(struct super_block *sb,
        bool bylower = ovl_hash_bylower(sb, upperdentry, lowerdentry,
                                        oip->index);
        int fsid = bylower ? oip->lowerpath->layer->fsid : 0;
-       bool is_dir;
+       bool is_dir, metacopy = false;
        unsigned long ino = 0;
        int err = -ENOMEM;
 
@@ -831,7 +875,7 @@ struct inode *ovl_get_inode(struct super_block *sb,
                }
        }
        ovl_fill_inode(inode, realinode->i_mode, realinode->i_rdev, ino, fsid);
-       ovl_inode_init(inode, upperdentry, lowerdentry);
+       ovl_inode_init(inode, upperdentry, lowerdentry, oip->lowerdata);
 
        if (upperdentry && ovl_is_impuredir(upperdentry))
                ovl_set_flag(OVL_IMPURE, inode);
@@ -839,8 +883,20 @@ struct inode *ovl_get_inode(struct super_block *sb,
        if (oip->index)
                ovl_set_flag(OVL_INDEX, inode);
 
+       if (upperdentry) {
+               err = ovl_check_metacopy_xattr(upperdentry);
+               if (err < 0)
+                       goto out_err;
+               metacopy = err;
+               if (!metacopy)
+                       ovl_set_flag(OVL_UPPERDATA, inode);
+       }
+
        OVL_I(inode)->redirect = oip->redirect;
 
+       if (bylower)
+               ovl_set_flag(OVL_CONST_INO, inode);
+
        /* Check for non-merge dir that may have whiteouts */
        if (is_dir) {
                if (((upperdentry && lowerdentry) || oip->numlower > 1) ||