coda: cleanup for upcall handling path

Make the code that processes upcall responses more straightforward, uncovered
at least one bad assumption.  We trusted that vc_inuse would be 0 when upcalls
are aborted, however the device may have been reopened.

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, 58 insertions, 63 deletions

diff --git a/fs/coda/upcall.c b/fs/coda/upcall.c
index a44ca4155fd5..44332efa8411 100644
--- a/fs/coda/upcall.c
+++ b/fs/coda/upcall.c
@@ -687,27 +687,27 @@ static inline void coda_waitfor_upcall(struct upc_req *vmp)
  * are all mapped to -EINTR, while showing a nice warning message. (jh)
  * 
  */
-static int coda_upcall(struct coda_sb_info *sbi, 
-                int inSize, int *outSize, 
-                union inputArgs *buffer) 
+static int coda_upcall(struct coda_sb_info *sbi,
+                       int inSize, int *outSize,
+                       union inputArgs *buffer)
 {
         struct venus_comm *vcommp;
         union outputArgs *out;
-        struct upc_req *req;
+        union inputArgs *sig_inputArgs;
+        struct upc_req *req, *sig_req;
         int error = 0;
 
         vcommp = sbi->sbi_vcomm;
-        if ( !vcommp->vc_inuse ) {
-                printk("No pseudo device in upcall comms at %p\n", vcommp);
-                return -ENXIO;
+        if (!vcommp->vc_inuse) {
+                printk(KERN_NOTICE "coda: Venus dead, not sending upcall\n");
+                return -ENXIO;
         }
 
         /* Format the request message. */
         req = upc_alloc();
-        if (!req) {
-                printk("Failed to allocate upc_req structure\n");
+        if (!req)
                 return -ENOMEM;
-        }
+
         req->uc_data = (void *)buffer;
         req->uc_flags = 0;
         req->uc_inSize = inSize;
@@ -715,13 +715,13 @@ static int coda_upcall(struct coda_sb_info *sbi,
         req->uc_opcode = ((union inputArgs *)buffer)->ih.opcode;
         req->uc_unique = ++vcommp->vc_seq;
         init_waitqueue_head(&req->uc_sleep);
-        
+
         /* Fill in the common input args. */
         ((union inputArgs *)buffer)->ih.unique = req->uc_unique;
 
         /* Append msg to pending queue and poke Venus. */
-        list_add_tail(&(req->uc_chain), &vcommp->vc_pending);
-        
+        list_add_tail(&req->uc_chain, &vcommp->vc_pending);
+
         wake_up_interruptible(&vcommp->vc_waitq);
         /* We can be interrupted while we wait for Venus to process
          * our request.  If the interrupt occurs before Venus has read
@@ -735,64 +735,59 @@ static int coda_upcall(struct coda_sb_info *sbi,
         /* Go to sleep.  Wake up on signals only after the timeout. */
         coda_waitfor_upcall(req);
 
-        if (vcommp->vc_inuse) {      /* i.e. Venus is still alive */
-            /* Op went through, interrupt or not... */
-            if (req->uc_flags & REQ_WRITE) {
+        /* Op went through, interrupt or not... */
+        if (req->uc_flags & REQ_WRITE) {
                 out = (union outputArgs *)req->uc_data;
                 /* here we map positive Venus errors to kernel errors */
                 error = -out->oh.result;
                 *outSize = req->uc_outSize;
                 goto exit;
-            }
-            if ( !(req->uc_flags & REQ_READ) && signal_pending(current)) { 
-                /* Interrupted before venus read it. */
-                list_del(&(req->uc_chain));
-                /* perhaps the best way to convince the app to
-                   give up? */
-                error = -EINTR;
+        }
+
+        error = -EINTR;
+        if ((req->uc_flags & REQ_ABORT) || !signal_pending(current)) {
+                printk(KERN_WARNING "coda: Unexpected interruption.\n");
                 goto exit;
-            } 
-            if ( (req->uc_flags & REQ_READ) && signal_pending(current) ) {
-                    /* interrupted after Venus did its read, send signal */
-                    union inputArgs *sig_inputArgs;
-                    struct upc_req *sig_req;
-                    
-                    list_del(&(req->uc_chain));
-                    error = -ENOMEM;
-                    sig_req = upc_alloc();
-                    if (!sig_req) goto exit;
-
-                    CODA_ALLOC((sig_req->uc_data), char *, sizeof(struct coda_in_hdr));
-                    if (!sig_req->uc_data) {
-                        upc_free(sig_req);
-                        goto exit;
-                    }
-                    
-                    error = -EINTR;
-                    sig_inputArgs = (union inputArgs *)sig_req->uc_data;
-                    sig_inputArgs->ih.opcode = CODA_SIGNAL;
-                    sig_inputArgs->ih.unique = req->uc_unique;
-                    
-                    sig_req->uc_flags = REQ_ASYNC;
-                    sig_req->uc_opcode = sig_inputArgs->ih.opcode;
-                    sig_req->uc_unique = sig_inputArgs->ih.unique;
-                    sig_req->uc_inSize = sizeof(struct coda_in_hdr);
-                    sig_req->uc_outSize = sizeof(struct coda_in_hdr);
-                    
-                    /* insert at head of queue! */
-                    list_add(&(sig_req->uc_chain), &vcommp->vc_pending);
-                    wake_up_interruptible(&vcommp->vc_waitq);
-            } else {
-                    printk("Coda: Strange interruption..\n");
-                    error = -EINTR;
-            }
-        } else {        /* If venus died i.e. !VC_OPEN(vcommp) */
-                printk("coda_upcall: Venus dead on (op,un) (%d.%d) flags %d\n",
-                       req->uc_opcode, req->uc_unique, req->uc_flags);
-                error = -ENODEV;
         }
 
- exit:
+        list_del(&(req->uc_chain));
+
+        /* Interrupted before venus read it. */
+        if (!(req->uc_flags & REQ_READ))
+                goto exit;
+
+        /* Venus saw the upcall, make sure we can send interrupt signal */
+        if (!vcommp->vc_inuse) {
+                printk(KERN_INFO "coda: Venus dead, not sending signal.\n");
+                goto exit;
+        }
+
+        error = -ENOMEM;
+        sig_req = upc_alloc();
+        if (!sig_req) goto exit;
+
+        CODA_ALLOC((sig_req->uc_data), char *, sizeof(struct coda_in_hdr));
+        if (!sig_req->uc_data) {
+                upc_free(sig_req);
+                goto exit;
+        }
+
+        error = -EINTR;
+        sig_inputArgs = (union inputArgs *)sig_req->uc_data;
+        sig_inputArgs->ih.opcode = CODA_SIGNAL;
+        sig_inputArgs->ih.unique = req->uc_unique;
+
+        sig_req->uc_flags = REQ_ASYNC;
+        sig_req->uc_opcode = sig_inputArgs->ih.opcode;
+        sig_req->uc_unique = sig_inputArgs->ih.unique;
+        sig_req->uc_inSize = sizeof(struct coda_in_hdr);
+        sig_req->uc_outSize = sizeof(struct coda_in_hdr);
+
+        /* insert at head of queue! */
+        list_add(&(sig_req->uc_chain), &vcommp->vc_pending);
+        wake_up_interruptible(&vcommp->vc_waitq);
+
+exit:
         upc_free(req);
         return error;
 }