Jeff Layton <jlayton@xxxxxxxxxx> writes: > On Fri, 2019-03-01 at 17:57 +0000, Luis Henriques wrote: >> The CephFS kernel client doesn't enforce quotas that are set in a >> directory that isn't visible in the mount point. For example, given the >> path '/dir1/dir2', if quotas are set in 'dir1' and the mount is done in with >> >> mount -t ceph <server>:<port>:/dir1/ /mnt >> >> then the client can't access the 'dir1' inode from the quota realm dir2 >> belongs to. >> >> This patch fixes this by simply doing an MDS LOOKUPINO Op and grabbing a >> reference to it (so that it doesn't disappear again). This also requires an >> extra field in ceph_snap_realm so that we know we have to release that >> reference when destroying the realm. >> >> Links: https://tracker.ceph.com/issues/3848 > > This bug looks unrelated to the patch description. Are you sure it's > correct? Ups! Looks like I truncated the bug number. Sorry about that, here's the correct link: https://tracker.ceph.com/issues/38482 Cheers, -- Luis >> Reported-by: Hendrik Peyerl <hpeyerl@xxxxxxxxxxxx> >> Signed-off-by: Luis Henriques <lhenriques@xxxxxxxx> >> --- >> fs/ceph/caps.c | 2 +- >> fs/ceph/quota.c | 30 +++++++++++++++++++++++++++--- >> fs/ceph/snap.c | 3 +++ >> fs/ceph/super.h | 2 ++ >> 4 files changed, 33 insertions(+), 4 deletions(-) >> >> diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c >> index bba28a5034ba..e79994ff53d6 100644 >> --- a/fs/ceph/caps.c >> +++ b/fs/ceph/caps.c >> @@ -1035,7 +1035,7 @@ static void drop_inode_snap_realm(struct ceph_inode_info *ci) >> list_del_init(&ci->i_snap_realm_item); >> ci->i_snap_realm_counter++; >> ci->i_snap_realm = NULL; >> - if (realm->ino == ci->i_vino.ino) >> + if ((realm->ino == ci->i_vino.ino) && !realm->own_inode) >> realm->inode = NULL; >> spin_unlock(&realm->inodes_with_caps_lock); >> ceph_put_snap_realm(ceph_sb_to_client(ci->vfs_inode.i_sb)->mdsc, >> diff --git a/fs/ceph/quota.c b/fs/ceph/quota.c >> index 9455d3aef0c3..f6b972d222e4 100644 >> --- a/fs/ceph/quota.c >> +++ b/fs/ceph/quota.c >> @@ -22,7 +22,16 @@ void ceph_adjust_quota_realms_count(struct inode *inode, bool inc) >> static inline bool ceph_has_realms_with_quotas(struct inode *inode) >> { >> struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc; >> - return atomic64_read(&mdsc->quotarealms_count) > 0; >> + struct super_block *sb = mdsc->fsc->sb; >> + >> + if (atomic64_read(&mdsc->quotarealms_count) > 0) >> + return true; >> + /* if root is the real CephFS root, we don't have quota realms */ >> + if (sb->s_root->d_inode && >> + (sb->s_root->d_inode->i_ino == CEPH_INO_ROOT)) >> + return false; >> + /* otherwise, we can't know for sure */ >> + return true; >> } >> >> void ceph_handle_quota(struct ceph_mds_client *mdsc, >> @@ -166,6 +175,7 @@ static bool check_quota_exceeded(struct inode *inode, enum quota_check_op op, >> return false; >> >> down_read(&mdsc->snap_rwsem); >> +restart: >> realm = ceph_inode(inode)->i_snap_realm; >> if (realm) >> ceph_get_snap_realm(mdsc, realm); >> @@ -176,8 +186,22 @@ static bool check_quota_exceeded(struct inode *inode, enum quota_check_op op, >> spin_lock(&realm->inodes_with_caps_lock); >> in = realm->inode ? igrab(realm->inode) : NULL; >> spin_unlock(&realm->inodes_with_caps_lock); >> - if (!in) >> - break; >> + if (!in) { >> + up_read(&mdsc->snap_rwsem); >> + in = ceph_lookup_inode(inode->i_sb, realm->ino); >> + down_read(&mdsc->snap_rwsem); >> + if (IS_ERR(in)) { >> + pr_warn("Can't lookup inode %llx (err: %ld)\n", >> + realm->ino, PTR_ERR(in)); >> + break; >> + } >> + spin_lock(&realm->inodes_with_caps_lock); >> + realm->inode = in; >> + realm->own_inode = true; >> + spin_unlock(&realm->inodes_with_caps_lock); >> + ceph_put_snap_realm(mdsc, realm); >> + goto restart; >> + } >> >> ci = ceph_inode(in); >> spin_lock(&ci->i_ceph_lock); >> diff --git a/fs/ceph/snap.c b/fs/ceph/snap.c >> index f74193da0e09..c84ed8e8526a 100644 >> --- a/fs/ceph/snap.c >> +++ b/fs/ceph/snap.c >> @@ -117,6 +117,7 @@ static struct ceph_snap_realm *ceph_create_snap_realm( >> >> atomic_set(&realm->nref, 1); /* for caller */ >> realm->ino = ino; >> + realm->own_inode = false; >> INIT_LIST_HEAD(&realm->children); >> INIT_LIST_HEAD(&realm->child_item); >> INIT_LIST_HEAD(&realm->empty_item); >> @@ -184,6 +185,8 @@ static void __destroy_snap_realm(struct ceph_mds_client *mdsc, >> kfree(realm->prior_parent_snaps); >> kfree(realm->snaps); >> ceph_put_snap_context(realm->cached_context); >> + if (realm->own_inode && realm->inode) >> + iput(realm->inode); >> kfree(realm); >> } >> >> diff --git a/fs/ceph/super.h b/fs/ceph/super.h >> index ce51e98b08ec..3f0d74d2150f 100644 >> --- a/fs/ceph/super.h >> +++ b/fs/ceph/super.h >> @@ -764,6 +764,8 @@ struct ceph_snap_realm { >> atomic_t nref; >> struct rb_node node; >> >> + bool own_inode; /* true if we hold a ref to the inode */ >> + >> u64 created, seq; >> u64 parent_ino; >> u64 parent_since; /* snapid when our current parent became so */
