coda: cleanup /dev/cfs open and close handling

- Make sure device index is not a negative number.
- Unlink queued requests when the device is closed to avoid passing them
  to the next opener.

Signed-off-by: Jan Harkes <jaharkes@cs.cmu.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 30 insertions, 31 deletions

diff --git a/fs/coda/psdev.c b/fs/coda/psdev.c
index 09382d47a4e1..6818c20372ca 100644
--- a/fs/coda/psdev.c
+++ b/fs/coda/psdev.c
@@ -272,56 +272,51 @@ out:
 
 static int coda_psdev_open(struct inode * inode, struct file * file)
 {
-        struct venus_comm *vcp;
-	int idx;
+	struct venus_comm *vcp;
+	int idx, err;
 
-	lock_kernel();
 	idx = iminor(inode);
-	if(idx >= MAX_CODADEVS) {
-		unlock_kernel();
+	if (idx < 0 || idx >= MAX_CODADEVS)
 		return -ENODEV;
-	}
 
+	lock_kernel();
+
+	err = -EBUSY;
 	vcp = &coda_comms[idx];
-	if(vcp->vc_inuse) {
-		unlock_kernel();
-		return -EBUSY;
-	}
-	
-	if (!vcp->vc_inuse++) {
+	if (!vcp->vc_inuse) {
+		vcp->vc_inuse++;
+
 		INIT_LIST_HEAD(&vcp->vc_pending);
 		INIT_LIST_HEAD(&vcp->vc_processing);
 		init_waitqueue_head(&vcp->vc_waitq);
 		vcp->vc_sb = NULL;
 		vcp->vc_seq = 0;
+
+		file->private_data = vcp;
+		err = 0;
 	}
-	
-	file->private_data = vcp;
 
 	unlock_kernel();
-        return 0;
+	return err;
 }
 
 
 static int coda_psdev_release(struct inode * inode, struct file * file)
 {
-        struct venus_comm *vcp = (struct venus_comm *) file->private_data;
-        struct upc_req *req, *tmp;
+	struct venus_comm *vcp = (struct venus_comm *) file->private_data;
+	struct upc_req *req, *tmp;
 
-	lock_kernel();
-	if ( !vcp->vc_inuse ) {
-		unlock_kernel();
+	if (!vcp || !vcp->vc_inuse ) {
 		printk("psdev_release: Not open.\n");
 		return -1;
 	}
 
-	if (--vcp->vc_inuse) {
-		unlock_kernel();
-		return 0;
-	}
-        
-        /* Wakeup clients so they can return. */
+	lock_kernel();
+
+	/* Wakeup clients so they can return. */
 	list_for_each_entry_safe(req, tmp, &vcp->vc_pending, uc_chain) {
+		list_del(&req->uc_chain);
+
 		/* Async requests need to be freed here */
 		if (req->uc_flags & REQ_ASYNC) {
 			CODA_FREE(req->uc_data, sizeof(struct coda_in_hdr));
@@ -330,13 +325,17 @@ static int coda_psdev_release(struct inode * inode, struct file * file)
 		}
 		req->uc_flags |= REQ_ABORT;
 		wake_up(&req->uc_sleep);
-        }
-        
-	list_for_each_entry(req, &vcp->vc_processing, uc_chain) {
+	}
+
+	list_for_each_entry_safe(req, tmp, &vcp->vc_processing, uc_chain) {
+		list_del(&req->uc_chain);
+
 		req->uc_flags |= REQ_ABORT;
-	        wake_up(&req->uc_sleep);
-        }
+		wake_up(&req->uc_sleep);
+	}
 
+	file->private_data = NULL;
+	vcp->vc_inuse--;
 	unlock_kernel();
 	return 0;
 }