From 3e9e3dbe0fe36c824ce2c5d7b05997c87a64bbdc Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Thu, 23 Jun 2005 22:04:20 -0700 Subject: [PATCH] [PATCH] knfsd: nfsd4: allow multiple lockowners >From the language of rfc3530 section 8.1.3 (e.g., the suggestion that a "process id" might be a reasonable lockowner value) it's conceivable that a client might want to use the same lockowner string on multiple files, so we may as well allow that. We expect each use of open_to_lockowner to create a distinct seqid stream, though. For now we're also allowing multiple uses of open_to_lockowner with the same open, though it seems unlikely clients would actually do that. Also add a comment reminding myself of some very non-scalable data structures. Signed-off-by: J. Bruce Fields Signed-off-by: Neil Brown Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/nfsd/nfs4state.c | 76 ++++++++++++++++++++------------------------- 1 file changed, 33 insertions(+), 43 deletions(-) diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index 22e76e3f06a5..26d00465c28a 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -2583,22 +2583,6 @@ nfs4_set_lock_denied(struct file_lock *fl, struct nfsd4_lock_denied *deny) deny->ld_type = NFS4_WRITE_LT; } -static struct nfs4_stateowner * -find_lockstateowner(struct xdr_netobj *owner, clientid_t *clid) -{ - struct nfs4_stateowner *local = NULL; - int i; - - for (i = 0; i < LOCK_HASH_SIZE; i++) { - list_for_each_entry(local, &lock_ownerid_hashtbl[i], so_idhash) { - if (!cmp_owner_str(local, owner, clid)) - continue; - return local; - } - } - return NULL; -} - static struct nfs4_stateowner * find_lockstateowner_str(struct inode *inode, clientid_t *clid, struct xdr_netobj *owner) @@ -2697,7 +2681,7 @@ check_lock_length(u64 offset, u64 length) int nfsd4_lock(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nfsd4_lock *lock) { - struct nfs4_stateowner *lock_sop = NULL, *open_sop = NULL; + struct nfs4_stateowner *open_sop = NULL; struct nfs4_stateid *lock_stp; struct file *filp; struct file_lock file_lock; @@ -2756,16 +2740,9 @@ nfsd4_lock(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nfsd4_lock strhashval = lock_ownerstr_hashval(fp->fi_inode, open_sop->so_client->cl_clientid.cl_id, &lock->v.new.owner); - /* - * If we already have this lock owner, the client is in - * error (or our bookeeping is wrong!) - * for asking for a 'new lock'. - */ - status = nfserr_bad_stateid; - lock_sop = find_lockstateowner(&lock->v.new.owner, - &lock->v.new.clientid); - if (lock_sop) - goto out; + /* XXX: Do we need to check for duplicate stateowners on + * the same file, or should they just be allowed (and + * create new stateids)? */ status = nfserr_resource; if (!(lock->lk_stateowner = alloc_init_lock_stateowner(strhashval, open_sop->so_client, open_stp, lock))) goto out; @@ -3056,8 +3033,11 @@ int nfsd4_release_lockowner(struct svc_rqst *rqstp, struct nfsd4_release_lockowner *rlockowner) { clientid_t *clid = &rlockowner->rl_clientid; - struct nfs4_stateowner *local = NULL; + struct nfs4_stateowner *sop; + struct nfs4_stateid *stp; struct xdr_netobj *owner = &rlockowner->rl_owner; + struct list_head matches; + int i; int status; dprintk("nfsd4_release_lockowner clientid: (%08x/%08x):\n", @@ -3073,22 +3053,32 @@ nfsd4_release_lockowner(struct svc_rqst *rqstp, struct nfsd4_release_lockowner * nfs4_lock_state(); - status = nfs_ok; - local = find_lockstateowner(owner, clid); - if (local) { - struct nfs4_stateid *stp; - - /* check for any locks held by any stateid - * associated with the (lock) stateowner */ - status = nfserr_locks_held; - list_for_each_entry(stp, &local->so_stateids, - st_perstateowner) { - if (check_for_locks(stp->st_vfs_file, local)) - goto out; + status = nfserr_locks_held; + /* XXX: we're doing a linear search through all the lockowners. + * Yipes! For now we'll just hope clients aren't really using + * release_lockowner much, but eventually we have to fix these + * data structures. */ + INIT_LIST_HEAD(&matches); + for (i = 0; i < LOCK_HASH_SIZE; i++) { + list_for_each_entry(sop, &lock_ownerid_hashtbl[i], so_idhash) { + if (!cmp_owner_str(sop, owner, clid)) + continue; + list_for_each_entry(stp, &sop->so_stateids, + st_perstateowner) { + if (check_for_locks(stp->st_vfs_file, sop)) + goto out; + /* Note: so_perclient unused for lockowners, + * so it's OK to fool with here. */ + list_add(&sop->so_perclient, &matches); + } } - /* no locks held by (lock) stateowner */ - status = nfs_ok; - release_stateowner(local); + } + /* Clients probably won't expect us to return with some (but not all) + * of the lockowner state released; so don't release any until all + * have been checked. */ + status = nfs_ok; + list_for_each_entry(sop, &matches, so_perclient) { + release_stateowner(sop); } out: nfs4_unlock_state(); -- 2.30.2