xnu-3789.41.3.tar.gz

[apple/xnu.git] / bsd / nfs / nfs_bio.c

diff --git a/bsd/nfs/nfs_bio.c b/bsd/nfs/nfs_bio.c
index c0715a2b0267b0e962183eeffc569ceea733cda3..acaf26c24a6c222e155640eae44d7ffda2d22fe2 100644 (file)
--- a/bsd/nfs/nfs_bio.c
+++ b/bsd/nfs/nfs_bio.c
@@ -97,6 +97,8 @@
 #include <sys/buf_internal.h>
 #include <libkern/OSAtomic.h>
 
+#define NFS_BIO_DBG(...) NFS_DBG(NFS_FAC_BIO, 7, ## __VA_ARGS__)
+
 kern_return_t  thread_terminate(thread_t); /* XXX */
 
 #define        NFSBUFHASH(np, lbn)     \
@@ -3797,7 +3799,29 @@ again:
                }
        }
 
-       if (req->r_achain.tqe_next == NFSREQNOLIST || req->r_achain.tqe_next == NFSIODCOMPLETING)
+       /*
+        * If we got here while being on the resendq we need to get off. This
+        * happens when the timer fires and errors out requests from nfs_sigintr
+        * or we receive a reply (UDP case) while being on the resend queue so
+        * we're just finishing up and are not going to be resent.
+        */
+       lck_mtx_lock(&req->r_mtx);
+       if (req->r_flags & R_RESENDQ) {
+               lck_mtx_lock(&nmp->nm_lock);
+               if (req->r_rchain.tqe_next != NFSREQNOLIST) {
+                       NFS_BIO_DBG("Proccessing async request on resendq. Removing");
+                       TAILQ_REMOVE(&nmp->nm_resendq, req, r_rchain);
+                       req->r_rchain.tqe_next = NFSREQNOLIST;
+                       assert(req->r_refs > 1);
+                       /* Remove resendq reference */
+                       req->r_refs--;
+               }
+               lck_mtx_unlock(&nmp->nm_lock);
+               req->r_flags &= ~R_RESENDQ;
+       }
+       lck_mtx_unlock(&req->r_mtx);
+
+       if (req->r_achain.tqe_next == NFSREQNOLIST)
                TAILQ_INSERT_TAIL(&nmp->nm_iodq, req, r_achain);
 
        /* If this mount doesn't already have an nfsiod working on it... */
@@ -3835,11 +3859,17 @@ nfs_asyncio_resend(struct nfsreq *req)
 
        if (nfs_mount_gone(nmp))
                return;
+
        nfs_gss_clnt_rpcdone(req);
        lck_mtx_lock(&nmp->nm_lock);
        if (!(req->r_flags & R_RESENDQ)) {
                TAILQ_INSERT_TAIL(&nmp->nm_resendq, req, r_rchain);
                req->r_flags |= R_RESENDQ;
+               /*
+                * We take a reference on this request so that it can't be
+                * destroyed while a resend is queued or in progress.
+                */
+               nfs_request_ref(req, 1);
        }
        nfs_mount_sock_thread_wake(nmp);
        lck_mtx_unlock(&nmp->nm_lock);