On Thu, 2020-11-12 at 15:23 +0000, Luis Henriques wrote: > This reverts commit dffdcd71458e699e839f0bf47c3d42d64210b939. > > When doing a rename across quota realms, there's a corner case that isn't > handled correctly. Here's a testcase: > > mkdir files limit > truncate files/file -s 10G > setfattr limit -n ceph.quota.max_bytes -v 1000000 > mv files limit/ > > The above will succeed because ftruncate(2) won't immediately notify the > MDSs with the new file size, and thus the quota realms stats won't be > updated. > > Since the possible fixes for this issue would have a huge performance impact, > the solution for now is to simply revert to returning -EXDEV when doing a cross > quota realms rename. > > URL: https://tracker.ceph.com/issues/48203 > Signed-off-by: Luis Henriques <lhenriques@xxxxxxx> > --- > fs/ceph/dir.c | 9 ++++---- > fs/ceph/quota.c | 58 +------------------------------------------------ > fs/ceph/super.h | 3 +-- > 3 files changed, 6 insertions(+), 64 deletions(-) > > diff --git a/fs/ceph/dir.c b/fs/ceph/dir.c > index a4d48370b2b3..858ee7362ff5 100644 > --- a/fs/ceph/dir.c > +++ b/fs/ceph/dir.c > @@ -1202,12 +1202,11 @@ static int ceph_rename(struct inode *old_dir, struct dentry *old_dentry, > op = CEPH_MDS_OP_RENAMESNAP; > else > return -EROFS; > - } else if (old_dir != new_dir) { > - err = ceph_quota_check_rename(mdsc, d_inode(old_dentry), > - new_dir); > - if (err) > - return err; > } > + /* don't allow cross-quota renames */ > + if ((old_dir != new_dir) && > + (!ceph_quota_is_same_realm(old_dir, new_dir))) > + return -EXDEV; > > > dout("rename dir %p dentry %p to dir %p dentry %p\n", > old_dir, old_dentry, new_dir, new_dentry); > diff --git a/fs/ceph/quota.c b/fs/ceph/quota.c > index 9b785f11e95a..4e32c9600ecc 100644 > --- a/fs/ceph/quota.c > +++ b/fs/ceph/quota.c > @@ -264,7 +264,7 @@ static struct ceph_snap_realm *get_quota_realm(struct ceph_mds_client *mdsc, > return NULL; > } > > > -static bool ceph_quota_is_same_realm(struct inode *old, struct inode *new) > +bool ceph_quota_is_same_realm(struct inode *old, struct inode *new) > { > struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(old->i_sb); > struct ceph_snap_realm *old_realm, *new_realm; > @@ -516,59 +516,3 @@ bool ceph_quota_update_statfs(struct ceph_fs_client *fsc, struct kstatfs *buf) > return is_updated; > } > > > -/* > - * ceph_quota_check_rename - check if a rename can be executed > - * @mdsc: MDS client instance > - * @old: inode to be copied > - * @new: destination inode (directory) > - * > - * This function verifies if a rename (e.g. moving a file or directory) can be > - * executed. It forces an rstat update in the @new target directory (and in the > - * source @old as well, if it's a directory). The actual check is done both for > - * max_files and max_bytes. > - * > - * This function returns 0 if it's OK to do the rename, or, if quotas are > - * exceeded, -EXDEV (if @old is a directory) or -EDQUOT. > - */ > -int ceph_quota_check_rename(struct ceph_mds_client *mdsc, > - struct inode *old, struct inode *new) > -{ > - struct ceph_inode_info *ci_old = ceph_inode(old); > - int ret = 0; > - > - if (ceph_quota_is_same_realm(old, new)) > - return 0; > - > - /* > - * Get the latest rstat for target directory (and for source, if a > - * directory) > - */ > - ret = ceph_do_getattr(new, CEPH_STAT_RSTAT, false); > - if (ret) > - return ret; > - > - if (S_ISDIR(old->i_mode)) { > - ret = ceph_do_getattr(old, CEPH_STAT_RSTAT, false); > - if (ret) > - return ret; > - ret = check_quota_exceeded(new, QUOTA_CHECK_MAX_BYTES_OP, > - ci_old->i_rbytes); > - if (!ret) > - ret = check_quota_exceeded(new, > - QUOTA_CHECK_MAX_FILES_OP, > - ci_old->i_rfiles + > - ci_old->i_rsubdirs); > - if (ret) > - ret = -EXDEV; > - } else { > - ret = check_quota_exceeded(new, QUOTA_CHECK_MAX_BYTES_OP, > - i_size_read(old)); > - if (!ret) > - ret = check_quota_exceeded(new, > - QUOTA_CHECK_MAX_FILES_OP, 1); > - if (ret) > - ret = -EDQUOT; > - } > - > - return ret; > -} > diff --git a/fs/ceph/super.h b/fs/ceph/super.h > index 482473e4cce1..8dbb0babddea 100644 > --- a/fs/ceph/super.h > +++ b/fs/ceph/super.h > @@ -1222,14 +1222,13 @@ extern void ceph_handle_quota(struct ceph_mds_client *mdsc, > struct ceph_mds_session *session, > struct ceph_msg *msg); > extern bool ceph_quota_is_max_files_exceeded(struct inode *inode); > +extern bool ceph_quota_is_same_realm(struct inode *old, struct inode *new); > extern bool ceph_quota_is_max_bytes_exceeded(struct inode *inode, > loff_t newlen); > extern bool ceph_quota_is_max_bytes_approaching(struct inode *inode, > loff_t newlen); > extern bool ceph_quota_update_statfs(struct ceph_fs_client *fsc, > struct kstatfs *buf); > -extern int ceph_quota_check_rename(struct ceph_mds_client *mdsc, > - struct inode *old, struct inode *new); > extern void ceph_cleanup_quotarealms_inodes(struct ceph_mds_client *mdsc); > > > #endif /* _FS_CEPH_SUPER_H */ Ok, looks reasonable for now. I'll note that we probably _could_ allow for cross-quota renames of regular files since we know that we're only dealing with a single inode. That said, it might be weird to see EXDEV on a directory but not a regular file in the same parent dir. -- Jeff Layton <jlayton@xxxxxxxxxx>
