Return-Path: linux-nfs-owner@vger.kernel.org Received: from mail-qc0-f178.google.com ([209.85.216.178]:56166 "EHLO mail-qc0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751656AbaHUPp4 (ORCPT ); Thu, 21 Aug 2014 11:45:56 -0400 Received: by mail-qc0-f178.google.com with SMTP id x3so9622483qcv.9 for ; Thu, 21 Aug 2014 08:45:55 -0700 (PDT) From: Jeff Layton To: linux-nfs@vger.kernel.org Cc: cluster-devel@redhat.com, Kinglong Mee Subject: [PATCH] lockd: rip out deferred lock handling from testlock codepath Date: Thu, 21 Aug 2014 11:45:48 -0400 Message-Id: <1408635948-30481-1-git-send-email-jlayton@primarydata.com> Sender: linux-nfs-owner@vger.kernel.org List-ID: As Kinglong points out, the nlm_block->b_fl field is no longer used at all. Also, vfs_test_lock in the generic locking code will only return FILE_LOCK_DEFERRED if FL_SLEEP is set, and it isn't here. The only other place that returns that value is the DLM lock code, but it only does that in dlm_posix_lock, never in dlm_posix_get. Remove all of the deferred locking code from the testlock codepath since it doesn't appear to ever be used anyway. I do have a small concern that this might cause a behavior change in the case where you have a block already sitting on the list when the testlock request comes in, but that looks like it doesn't really work properly anyway. I think it's best to just pass that down to vfs_test_lock and let the filesystem report that instead of trying to infer what's going on with the lock by looking at an existing block. Cc: cluster-devel@redhat.com Reported-by: Kinglong Mee Signed-off-by: Jeff Layton --- fs/lockd/svclock.c | 55 +++++---------------------------------------- include/linux/lockd/lockd.h | 1 - 2 files changed, 6 insertions(+), 50 deletions(-) diff --git a/fs/lockd/svclock.c b/fs/lockd/svclock.c index acfa94d5b489..13db95f54176 100644 --- a/fs/lockd/svclock.c +++ b/fs/lockd/svclock.c @@ -245,7 +245,6 @@ nlmsvc_create_block(struct svc_rqst *rqstp, struct nlm_host *host, block->b_daemon = rqstp->rq_server; block->b_host = host; block->b_file = file; - block->b_fl = NULL; file->f_count++; /* Add to file's list of blocks */ @@ -295,7 +294,6 @@ static void nlmsvc_free_block(struct kref *kref) nlmsvc_freegrantargs(block->b_call); nlmsvc_release_call(block->b_call); nlm_release_file(block->b_file); - kfree(block->b_fl); kfree(block); } @@ -508,7 +506,6 @@ nlmsvc_testlock(struct svc_rqst *rqstp, struct nlm_file *file, struct nlm_host *host, struct nlm_lock *lock, struct nlm_lock *conflock, struct nlm_cookie *cookie) { - struct nlm_block *block = NULL; int error; __be32 ret; @@ -519,63 +516,26 @@ nlmsvc_testlock(struct svc_rqst *rqstp, struct nlm_file *file, (long long)lock->fl.fl_start, (long long)lock->fl.fl_end); - /* Get existing block (in case client is busy-waiting) */ - block = nlmsvc_lookup_block(file, lock); - - if (block == NULL) { - struct file_lock *conf = kzalloc(sizeof(*conf), GFP_KERNEL); - - if (conf == NULL) - return nlm_granted; - block = nlmsvc_create_block(rqstp, host, file, lock, cookie); - if (block == NULL) { - kfree(conf); - return nlm_granted; - } - block->b_fl = conf; - } - if (block->b_flags & B_QUEUED) { - dprintk("lockd: nlmsvc_testlock deferred block %p flags %d fl %p\n", - block, block->b_flags, block->b_fl); - if (block->b_flags & B_TIMED_OUT) { - nlmsvc_unlink_block(block); - ret = nlm_lck_denied; - goto out; - } - if (block->b_flags & B_GOT_CALLBACK) { - nlmsvc_unlink_block(block); - if (block->b_fl != NULL - && block->b_fl->fl_type != F_UNLCK) { - lock->fl = *block->b_fl; - goto conf_lock; - } else { - ret = nlm_granted; - goto out; - } - } - ret = nlm_drop_reply; - goto out; - } - if (locks_in_grace(SVC_NET(rqstp))) { ret = nlm_lck_denied_grace_period; goto out; } + error = vfs_test_lock(file->f_file, &lock->fl); - if (error == FILE_LOCK_DEFERRED) { - ret = nlmsvc_defer_lock_rqst(rqstp, block); - goto out; - } if (error) { + /* We can't currently deal with deferred test requests */ + if (error == FILE_LOCK_DEFERRED) + WARN_ON_ONCE(1); + ret = nlm_lck_denied_nolocks; goto out; } + if (lock->fl.fl_type == F_UNLCK) { ret = nlm_granted; goto out; } -conf_lock: dprintk("lockd: conflicting lock(ty=%d, %Ld-%Ld)\n", lock->fl.fl_type, (long long)lock->fl.fl_start, (long long)lock->fl.fl_end); @@ -589,8 +549,6 @@ conf_lock: locks_release_private(&lock->fl); ret = nlm_lck_denied; out: - if (block) - nlmsvc_release_block(block); return ret; } @@ -661,7 +619,6 @@ nlmsvc_cancel_blocked(struct net *net, struct nlm_file *file, struct nlm_lock *l * This is a callback from the filesystem for VFS file lock requests. * It will be used if lm_grant is defined and the filesystem can not * respond to the request immediately. - * For GETLK request it will copy the reply to the nlm_block. * For SETLK or SETLKW request it will get the local posix lock. * In all cases it will move the block to the head of nlm_blocked q where * nlmsvc_retry_blocked() can send back a reply for SETLKW or revisit the diff --git a/include/linux/lockd/lockd.h b/include/linux/lockd/lockd.h index 219d79627c05..ff82a32871b5 100644 --- a/include/linux/lockd/lockd.h +++ b/include/linux/lockd/lockd.h @@ -178,7 +178,6 @@ struct nlm_block { unsigned char b_granted; /* VFS granted lock */ struct nlm_file * b_file; /* file in question */ struct cache_req * b_cache_req; /* deferred request handling */ - struct file_lock * b_fl; /* set for GETLK */ struct cache_deferred_req * b_deferred_req; unsigned int b_flags; /* block flags */ #define B_QUEUED 1 /* lock queued */ -- 1.9.3