Return-Path: linux-nfs-owner@vger.kernel.org Received: from mail-ig0-f175.google.com ([209.85.213.175]:37537 "EHLO mail-ig0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758643AbaDVV3T (ORCPT ); Tue, 22 Apr 2014 17:29:19 -0400 Received: by mail-ig0-f175.google.com with SMTP id h3so3558293igd.8 for ; Tue, 22 Apr 2014 14:29:18 -0700 (PDT) From: Weston Andros Adamson To: trond.myklebust@primarydata.com Cc: linux-nfs@vger.kernel.org, Weston Andros Adamson Subject: [PATCH 14/17] pnfs: support multiple verfs per direct req Date: Tue, 22 Apr 2014 17:29:22 -0400 Message-Id: <1398202165-78897-15-git-send-email-dros@primarydata.com> In-Reply-To: <1398202165-78897-1-git-send-email-dros@primarydata.com> References: <1398202165-78897-1-git-send-email-dros@primarydata.com> Sender: linux-nfs-owner@vger.kernel.org List-ID: Support direct requests that span multiple pnfs data servers by comparing nfs_pgio_header->verf to a cached verf in pnfs_commit_bucket. Continue to use dreq->verf if the MDS is used / non-pNFS. Signed-off-by: Weston Andros Adamson --- fs/nfs/direct.c | 84 ++++++++++++++++++++++++++++++++++++++++++------- fs/nfs/nfs4filelayout.c | 3 ++ include/linux/nfs.h | 5 ++- include/linux/nfs_xdr.h | 2 ++ 4 files changed, 82 insertions(+), 12 deletions(-) diff --git a/fs/nfs/direct.c b/fs/nfs/direct.c index 9d968ca..53b86e6 100644 --- a/fs/nfs/direct.c +++ b/fs/nfs/direct.c @@ -90,7 +90,7 @@ struct nfs_direct_req { int flags; #define NFS_ODIRECT_DO_COMMIT (1) /* an unstable reply was received */ #define NFS_ODIRECT_RESCHED_WRITES (2) /* write verification failed */ - struct nfs_writeverf verf; /* unstable write verifier */ + struct nfs_writeverf verf; /* unstable write verifier */ }; static const struct nfs_pgio_completion_ops nfs_direct_write_completion_ops; @@ -108,6 +108,70 @@ static inline int put_dreq(struct nfs_direct_req *dreq) return atomic_dec_and_test(&dreq->io_count); } +/* + * nfs_direct_set_or_cmp_hdr_verf - ensure that the same verifier is used + * for all requests (to each sever) in a + * direct io request. + * @dreq - direct request possibly spanning multiple servers + * @hdr - pageio header to validate against previously seen verfs + * + * If a verf has yet to be seen for the server associated with @hdr, set + * the verf for that server and return 0. + * If a verf has been seen for this server, compare @hdr->verf to it and + * return the result. + */ +static int nfs_direct_set_or_cmp_hdr_verf(struct nfs_direct_req *dreq, + struct nfs_pgio_header *hdr) +{ + struct nfs_writeverf *ds_verf = &dreq->verf; + struct nfs_client *ds_clp = hdr->data.write->ds_clp; + int ds_idx = hdr->data.write->ds_idx; + + if (ds_clp) { + /* pNFS is in use, use the DS verf */ + if (ds_idx > dreq->ds_cinfo.nbuckets) + WARN_ON_ONCE(1); + else + ds_verf = &dreq->ds_cinfo.buckets[ds_idx].direct_verf; + } + if (ds_verf->committed < 0) { + memcpy(ds_verf, hdr->verf, sizeof(struct nfs_writeverf)); + WARN_ON_ONCE(ds_verf->committed < 0); + return 0; + } + return memcmp(ds_verf, hdr->verf, sizeof(struct nfs_writeverf)); +} + +/* + * nfs_direct_cmp_commit_data_verf - check that a write verifier from a commit + * matches the verifier seen on write from + * the same server. + * @dreq - direct request possibly spanning multiple servers + * @hdr - pageio header to validate against previously seen verfs + * + * This function relies on nfs_direct_set_or_cmp_hdr_verf being called at least + * once to set the verf for this server - this is OK because both called (and + * only called) in the unstable write path. + * + * Compare @hdr->verf to it and return the result. + */ +static int nfs_direct_cmp_commit_data_verf(struct nfs_direct_req *dreq, + struct nfs_commit_data *data) +{ + struct nfs_writeverf *ds_verf = &dreq->verf; + int ds_idx = data->ds_commit_index; + + if (data->ds_clp) { + /* pNFS is in use, use the DS verf */ + if (ds_idx > dreq->ds_cinfo.nbuckets) + WARN_ON_ONCE(1); + else + ds_verf = &dreq->ds_cinfo.buckets[ds_idx].direct_verf; + } + WARN_ON_ONCE(ds_verf->committed < 0); + return memcmp(ds_verf, &data->verf, sizeof(struct nfs_writeverf)); +} + /** * nfs_direct_IO - NFS address space operation for direct I/O * @rw: direction (read or write) @@ -168,6 +232,7 @@ static inline struct nfs_direct_req *nfs_direct_req_alloc(void) kref_get(&dreq->kref); init_completion(&dreq->completion); INIT_LIST_HEAD(&dreq->mds_cinfo.list); + dreq->verf.committed = NFS_INVALID_STABLE_HOW; /* not set yet */ INIT_WORK(&dreq->work, nfs_direct_write_schedule_work); spin_lock_init(&dreq->lock); @@ -602,7 +667,7 @@ static void nfs_direct_commit_complete(struct nfs_commit_data *data) dprintk("NFS: %5u commit failed with error %d.\n", data->task.tk_pid, status); dreq->flags = NFS_ODIRECT_RESCHED_WRITES; - } else if (memcmp(&dreq->verf, &data->verf, sizeof(data->verf))) { + } else if (nfs_direct_cmp_commit_data_verf(dreq, data)) { dprintk("NFS: %5u commit verify failed\n", data->task.tk_pid); dreq->flags = NFS_ODIRECT_RESCHED_WRITES; } @@ -810,16 +875,13 @@ static void nfs_direct_write_completion(struct nfs_pgio_header *hdr) } else if (test_bit(NFS_IOHDR_NEED_COMMIT, &hdr->flags)) { if (dreq->flags == NFS_ODIRECT_RESCHED_WRITES) bit = NFS_IOHDR_NEED_RESCHED; - else if (dreq->flags == 0) { - memcpy(&dreq->verf, hdr->verf, - sizeof(dreq->verf)); - bit = NFS_IOHDR_NEED_COMMIT; - dreq->flags = NFS_ODIRECT_DO_COMMIT; - } else if (dreq->flags == NFS_ODIRECT_DO_COMMIT) { - if (memcmp(&dreq->verf, hdr->verf, sizeof(dreq->verf))) { - dreq->flags = NFS_ODIRECT_RESCHED_WRITES; + else { + if (dreq->flags == 0) + dreq->flags = NFS_ODIRECT_DO_COMMIT; + + if (nfs_direct_set_or_cmp_hdr_verf(dreq, hdr)) bit = NFS_IOHDR_NEED_RESCHED; - } else + else bit = NFS_IOHDR_NEED_COMMIT; } } diff --git a/fs/nfs/nfs4filelayout.c b/fs/nfs/nfs4filelayout.c index cfd76bd..9a91f4f 100644 --- a/fs/nfs/nfs4filelayout.c +++ b/fs/nfs/nfs4filelayout.c @@ -603,6 +603,7 @@ filelayout_write_pagelist(struct nfs_write_data *data, int sync) data->write_done_cb = filelayout_write_done_cb; atomic_inc(&ds->ds_clp->cl_count); data->ds_clp = ds->ds_clp; + data->ds_idx = idx; fh = nfs4_fl_select_ds_fh(lseg, j); if (fh) data->args.fh = fh; @@ -875,6 +876,8 @@ filelayout_alloc_commit_info(struct pnfs_layout_segment *lseg, for (i = 0; i < size; i++) { INIT_LIST_HEAD(&buckets[i].written); INIT_LIST_HEAD(&buckets[i].committing); + /* mark direct verifier as unset */ + buckets[i].direct_verf.committed = NFS_INVALID_STABLE_HOW; } spin_lock(cinfo->lock); diff --git a/include/linux/nfs.h b/include/linux/nfs.h index 3e794c1..610af51 100644 --- a/include/linux/nfs.h +++ b/include/linux/nfs.h @@ -46,6 +46,9 @@ static inline void nfs_copy_fh(struct nfs_fh *target, const struct nfs_fh *sourc enum nfs3_stable_how { NFS_UNSTABLE = 0, NFS_DATA_SYNC = 1, - NFS_FILE_SYNC = 2 + NFS_FILE_SYNC = 2, + + /* used by direct.c to mark verf as invalid */ + NFS_INVALID_STABLE_HOW = -1 }; #endif /* _LINUX_NFS_H */ diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h index 239274d..f94d804 100644 --- a/include/linux/nfs_xdr.h +++ b/include/linux/nfs_xdr.h @@ -1129,6 +1129,7 @@ struct pnfs_commit_bucket { struct list_head committing; struct pnfs_layout_segment *wlseg; struct pnfs_layout_segment *clseg; + struct nfs_writeverf direct_verf; }; struct pnfs_ds_commit_info { @@ -1289,6 +1290,7 @@ struct nfs_write_data { __u64 mds_offset; /* Filelayout dense stripe */ struct nfs_page_array pages; struct nfs_client *ds_clp; /* pNFS data server */ + int ds_idx; /* ds index if ds_clp is set */ }; /* used as flag bits in nfs_pgio_header */ -- 1.8.5.2 (Apple Git-48)