[PATCH 11/12] fs/locks: merge posix_unblock_lock() and locks_delete_block()

From: NeilBrown
Date: Thu Nov 29 2018 - 18:07:03 EST


posix_unblock_lock() is not specific to posix locks, and behaves
nearly identically to locks_delete_block() - the former returning a
status while the later doesn't.

So discard posix_unblock_lock() and use locks_delete_block() instead,
after giving that function an appropriate return value.

Signed-off-by: NeilBrown <neilb@xxxxxxxx>
Reviewed-by: J. Bruce Fields <bfields@xxxxxxxxxx>
---
fs/cifs/file.c | 2 +-
fs/lockd/svclock.c | 2 +-
fs/locks.c | 36 +++++++++++++-----------------------
fs/nfsd/nfs4state.c | 6 +++---
include/linux/fs.h | 4 ++--
5 files changed, 20 insertions(+), 30 deletions(-)

diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index d7ed895e05d1..94c3575e850c 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -1106,7 +1106,7 @@ cifs_posix_lock_set(struct file *file, struct file_lock *flock)
rc = wait_event_interruptible(flock->fl_wait, !flock->fl_blocker);
if (!rc)
goto try_again;
- posix_unblock_lock(flock);
+ locks_delete_block(flock);
}
return rc;
}
diff --git a/fs/lockd/svclock.c b/fs/lockd/svclock.c
index 74330daeab71..ea719cdd6a36 100644
--- a/fs/lockd/svclock.c
+++ b/fs/lockd/svclock.c
@@ -276,7 +276,7 @@ static int nlmsvc_unlink_block(struct nlm_block *block)
dprintk("lockd: unlinking block %p...\n", block);

/* Remove block from list */
- status = posix_unblock_lock(&block->b_call->a_args.lock.fl);
+ status = locks_delete_block(&block->b_call->a_args.lock.fl);
nlmsvc_remove_block(block);
return status;
}
diff --git a/fs/locks.c b/fs/locks.c
index 7a55d6feb12a..75a03a9d666e 100644
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -748,8 +748,16 @@ static void __locks_wake_up_blocks(struct file_lock *blocker)
}
}

-static void locks_delete_block(struct file_lock *waiter)
+/**
+ * locks_delete_lock - stop waiting for a file lock
+ * @waiter: the lock which was waiting
+ *
+ * lockd/nfsd need to disconnect the lock while working on it.
+ */
+int locks_delete_block(struct file_lock *waiter)
{
+ int status = -ENOENT;
+
/*
* If fl_blocker is NULL, it won't be set again as this thread
* "owns" the lock and is the only one that might try to claim
@@ -765,10 +773,14 @@ static void locks_delete_block(struct file_lock *waiter)
list_empty(&waiter->fl_blocked_requests))
return status;
spin_lock(&blocked_lock_lock);
+ if (waiter->fl_blocker)
+ status = 0;
__locks_wake_up_blocks(waiter);
__locks_delete_block(waiter);
spin_unlock(&blocked_lock_lock);
+ return status;
}
+EXPORT_SYMBOL(locks_delete_block);

/* Insert waiter into blocker's block list.
* We use a circular list so that processes can be easily woken up in
@@ -2675,28 +2687,6 @@ void locks_remove_file(struct file *filp)
spin_unlock(&ctx->flc_lock);
}

-/**
- * posix_unblock_lock - stop waiting for a file lock
- * @waiter: the lock which was waiting
- *
- * lockd needs to block waiting for locks.
- */
-int
-posix_unblock_lock(struct file_lock *waiter)
-{
- int status = -ENOENT;
-
- spin_lock(&blocked_lock_lock);
- if (waiter->fl_blocker) {
- __locks_wake_up_blocks(waiter);
- __locks_delete_block(waiter);
- status = 0;
- }
- spin_unlock(&blocked_lock_lock);
- return status;
-}
-EXPORT_SYMBOL(posix_unblock_lock);
-
/**
* vfs_cancel_lock - file byte range unblock lock
* @filp: The file to apply the unblock to
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index f093fbe47133..a334828723fa 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -238,7 +238,7 @@ find_blocked_lock(struct nfs4_lockowner *lo, struct knfsd_fh *fh,
}
spin_unlock(&nn->blocked_locks_lock);
if (found)
- posix_unblock_lock(&found->nbl_lock);
+ locks_delete_block(&found->nbl_lock);
return found;
}

@@ -293,7 +293,7 @@ remove_blocked_locks(struct nfs4_lockowner *lo)
nbl = list_first_entry(&reaplist, struct nfsd4_blocked_lock,
nbl_lru);
list_del_init(&nbl->nbl_lru);
- posix_unblock_lock(&nbl->nbl_lock);
+ locks_delete_block(&nbl->nbl_lock);
free_blocked_lock(nbl);
}
}
@@ -4863,7 +4863,7 @@ nfs4_laundromat(struct nfsd_net *nn)
nbl = list_first_entry(&reaplist,
struct nfsd4_blocked_lock, nbl_lru);
list_del_init(&nbl->nbl_lru);
- posix_unblock_lock(&nbl->nbl_lock);
+ locks_delete_block(&nbl->nbl_lock);
free_blocked_lock(nbl);
}
out:
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 16df3a7df378..26a8607b3c3c 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1124,7 +1124,7 @@ extern void locks_remove_file(struct file *);
extern void locks_release_private(struct file_lock *);
extern void posix_test_lock(struct file *, struct file_lock *);
extern int posix_lock_file(struct file *, struct file_lock *, struct file_lock *);
-extern int posix_unblock_lock(struct file_lock *);
+extern int locks_delete_block(struct file_lock *);
extern int vfs_test_lock(struct file *, struct file_lock *);
extern int vfs_lock_file(struct file *, unsigned int, struct file_lock *, struct file_lock *);
extern int vfs_cancel_lock(struct file *filp, struct file_lock *fl);
@@ -1214,7 +1214,7 @@ static inline int posix_lock_file(struct file *filp, struct file_lock *fl,
return -ENOLCK;
}

-static inline int posix_unblock_lock(struct file_lock *waiter)
+static inline int locks_delete_block(struct file_lock *waiter)
{
return -ENOENT;
}