diff options
author | Jeff Layton <jlayton@primarydata.com> | 2014-08-09 10:22:40 -0400 |
---|---|---|
committer | J. Bruce Fields <bfields@redhat.com> | 2014-08-17 12:00:13 -0400 |
commit | 6bcc034eac79873468cdfd1ccea9f25ee67c4500 (patch) | |
tree | b3996e0662afc5bc709a9ec286e1f5034952f320 /fs/nfsd/nfs4state.c | |
parent | ef9b16dc6de692865e898a35e750119b5b9c82c5 (diff) |
nfsd: protect lease-related nfs4_file fields with fi_lock
Currently these fields are protected with the state_lock, but that
doesn't really make a lot of sense. These fields are "private" to the
nfs4_file, and can be protected with the more granular fi_lock.
The fi_lock is already held when setting these fields. Make the code
hold the fp->fi_lock when clearing the lease-related fields in the
nfs4_file, and no longer require that the state_lock be held when
calling into this function.
To prevent lock inversion with the i_lock, we also move the vfs_setlease
and fput calls outside of the fi_lock. This also sets us up for allowing
vfs_setlease calls to block in the future.
Finally, remove a redundant NULL pointer check. unhash_delegation_locked
locks the fp->fi_lock prior to that check, so fp in that function must
never be NULL.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Diffstat (limited to 'fs/nfsd/nfs4state.c')
-rw-r--r-- | fs/nfsd/nfs4state.c | 22 |
1 files changed, 13 insertions, 9 deletions
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index 2e80a59e7e91..309ec3b1090a 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c | |||
@@ -673,15 +673,20 @@ nfs4_put_stid(struct nfs4_stid *s) | |||
673 | 673 | ||
674 | static void nfs4_put_deleg_lease(struct nfs4_file *fp) | 674 | static void nfs4_put_deleg_lease(struct nfs4_file *fp) |
675 | { | 675 | { |
676 | lockdep_assert_held(&state_lock); | 676 | struct file *filp = NULL; |
677 | struct file_lock *fl; | ||
677 | 678 | ||
678 | if (!fp->fi_lease) | 679 | spin_lock(&fp->fi_lock); |
679 | return; | 680 | if (fp->fi_lease && atomic_dec_and_test(&fp->fi_delegees)) { |
680 | if (atomic_dec_and_test(&fp->fi_delegees)) { | 681 | swap(filp, fp->fi_deleg_file); |
681 | vfs_setlease(fp->fi_deleg_file, F_UNLCK, &fp->fi_lease); | 682 | fl = fp->fi_lease; |
682 | fp->fi_lease = NULL; | 683 | fp->fi_lease = NULL; |
683 | fput(fp->fi_deleg_file); | 684 | } |
684 | fp->fi_deleg_file = NULL; | 685 | spin_unlock(&fp->fi_lock); |
686 | |||
687 | if (filp) { | ||
688 | vfs_setlease(filp, F_UNLCK, &fl); | ||
689 | fput(filp); | ||
685 | } | 690 | } |
686 | } | 691 | } |
687 | 692 | ||
@@ -717,8 +722,7 @@ unhash_delegation_locked(struct nfs4_delegation *dp) | |||
717 | list_del_init(&dp->dl_recall_lru); | 722 | list_del_init(&dp->dl_recall_lru); |
718 | list_del_init(&dp->dl_perfile); | 723 | list_del_init(&dp->dl_perfile); |
719 | spin_unlock(&fp->fi_lock); | 724 | spin_unlock(&fp->fi_lock); |
720 | if (fp) | 725 | nfs4_put_deleg_lease(fp); |
721 | nfs4_put_deleg_lease(fp); | ||
722 | } | 726 | } |
723 | 727 | ||
724 | static void destroy_delegation(struct nfs4_delegation *dp) | 728 | static void destroy_delegation(struct nfs4_delegation *dp) |