From: andros@netapp.com Subject: [PATCH 1/3] SUNRPC add deferral processing callbacks Date: Wed, 22 Oct 2008 14:12:04 -0400 Message-ID: <1224699126-3762-2-git-send-email-andros@netapp.com> References: <> <1224699126-3762-1-git-send-email-andros@netapp.com> Cc: androsadamson@gmail.com, Andy Adamson To: linux-nfs@vger.kernel.org Return-path: Received: from mx2.netapp.com ([216.240.18.37]:46927 "EHLO mx2.netapp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753341AbYJVSMR (ORCPT ); Wed, 22 Oct 2008 14:12:17 -0400 In-Reply-To: <1224699126-3762-1-git-send-email-andros@netapp.com> Sender: linux-nfs-owner@vger.kernel.org List-ID: From: Andy Adamson For EOS, NFSD compound RPC deferred processing should restart operation which caused the deferral. Add a callback and a defer_data pointer in svc_rqst to enable svc_defer to save partial result state in the deferral request. Dynamically allocate page pointers in the save state callback. A failure to save state will free the deferred request and return NULL which signals the cache to return -ETIMEDOUT (NFSERR_DELAY). Add page pointer storage to svc_deferred_req to cache the pages holding the partially processed request. Add callbacks and a defer_data pointer in svc_deferred_request to enable svc_deferred_recv to restore and release the partial result state. Signed-off-by: Andy Adamson --- include/linux/sunrpc/svc.h | 10 ++++++++++ net/sunrpc/svc.c | 4 ++++ net/sunrpc/svc_xprt.c | 10 +++++++++- 3 files changed, 23 insertions(+), 1 deletions(-) diff --git a/include/linux/sunrpc/svc.h b/include/linux/sunrpc/svc.h index 3afe7fb..8cc8a74 100644 --- a/include/linux/sunrpc/svc.h +++ b/include/linux/sunrpc/svc.h @@ -216,6 +216,9 @@ struct svc_rqst { struct svc_cred rq_cred; /* auth info */ void * rq_xprt_ctxt; /* transport specific context ptr */ struct svc_deferred_req*rq_deferred; /* deferred request we are replaying */ + /* callback to save deferred request state */ + int (*rq_save_state)(struct svc_rqst *, struct svc_deferred_req *); + void *rq_defer_data; /* defer state data to save */ size_t rq_xprt_hlen; /* xprt header len */ struct xdr_buf rq_arg; @@ -324,6 +327,13 @@ struct svc_deferred_req { union svc_addr_u daddr; /* where reply must come from */ struct cache_deferred_req handle; size_t xprt_hlen; + /* callbacks to restore and release deferred request state + * set in rq_save_state */ + void (*restore_state)(struct svc_rqst *, struct svc_deferred_req *); + void (*release_state)(struct svc_deferred_req *); + void *defer_data; /* defer state data */ + struct page **respages; + int respages_used; int argslen; __be32 args[0]; }; diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c index 54c98d8..8a6c69c 100644 --- a/net/sunrpc/svc.c +++ b/net/sunrpc/svc.c @@ -1024,6 +1024,10 @@ svc_process(struct svc_rqst *rqstp) /* Will be turned off only in gss privacy case: */ rqstp->rq_splice_ok = 1; + /* Reset deferred processing */ + rqstp->rq_defer_data = NULL; + rqstp->rq_save_state = NULL; + /* Setup reply header */ rqstp->rq_xprt->xpt_ops->xpo_prep_reply_hdr(rqstp); diff --git a/net/sunrpc/svc_xprt.c b/net/sunrpc/svc_xprt.c index bf5b5cd..0a8d6ab 100644 --- a/net/sunrpc/svc_xprt.c +++ b/net/sunrpc/svc_xprt.c @@ -903,6 +903,8 @@ static void svc_revisit(struct cache_deferred_req *dreq, int too_many) struct svc_xprt *xprt = dr->xprt; if (too_many) { + if (dr->release_state) + dr->release_state(dr); svc_xprt_put(xprt); kfree(dr); return; @@ -941,7 +943,7 @@ static struct cache_deferred_req *svc_defer(struct cache_req *req) size_t size; /* FIXME maybe discard if size too large */ size = sizeof(struct svc_deferred_req) + rqstp->rq_arg.len; - dr = kmalloc(size, GFP_KERNEL); + dr = kzalloc(size, GFP_KERNEL); if (dr == NULL) return NULL; @@ -958,6 +960,10 @@ static struct cache_deferred_req *svc_defer(struct cache_req *req) memcpy(dr->args, rqstp->rq_arg.head[0].iov_base - skip, dr->argslen << 2); } + if (rqstp->rq_save_state && !rqstp->rq_save_state(rqstp, dr)) { + kfree(dr); + return NULL; + } svc_xprt_get(rqstp->rq_xprt); dr->xprt = rqstp->rq_xprt; @@ -986,6 +992,8 @@ static int svc_deferred_recv(struct svc_rqst *rqstp) rqstp->rq_xprt_hlen = dr->xprt_hlen; rqstp->rq_daddr = dr->daddr; rqstp->rq_respages = rqstp->rq_pages; + if (dr->restore_state) + dr->restore_state(rqstp, dr); return (dr->argslen<<2) - dr->xprt_hlen; } -- 1.5.4.3