Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754181AbbLLU1H (ORCPT ); Sat, 12 Dec 2015 15:27:07 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:38585 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754114AbbLLU04 (ORCPT ); Sat, 12 Dec 2015 15:26:56 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jeff Layton , Trond Myklebust Subject: [PATCH 4.3 64/71] nfs4: resend LAYOUTGET when there is a race that changes the seqid Date: Sat, 12 Dec 2015 12:06:28 -0800 Message-Id: <20151212200539.890284792@linuxfoundation.org> X-Mailer: git-send-email 2.6.4 In-Reply-To: <20151212200536.761001328@linuxfoundation.org> References: <20151212200536.761001328@linuxfoundation.org> User-Agent: quilt/0.64 MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3365 Lines: 102 4.3-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jeff Layton commit 4f2e9dce0c6348a95eaa56ade9bab18572221088 upstream. pnfs_layout_process will check the returned layout stateid against what the kernel has in-core. If it turns out that the stateid we received is older, then we should resend the LAYOUTGET instead of falling back to MDS I/O. Signed-off-by: Jeff Layton Signed-off-by: Trond Myklebust Signed-off-by: Greg Kroah-Hartman --- fs/nfs/pnfs.c | 56 +++++++++++++++++++++++++++++++------------------------- 1 file changed, 31 insertions(+), 25 deletions(-) --- a/fs/nfs/pnfs.c +++ b/fs/nfs/pnfs.c @@ -872,33 +872,38 @@ send_layoutget(struct pnfs_layout_hdr *l dprintk("--> %s\n", __func__); - lgp = kzalloc(sizeof(*lgp), gfp_flags); - if (lgp == NULL) - return NULL; - - i_size = i_size_read(ino); + /* + * Synchronously retrieve layout information from server and + * store in lseg. If we race with a concurrent seqid morphing + * op, then re-send the LAYOUTGET. + */ + do { + lgp = kzalloc(sizeof(*lgp), gfp_flags); + if (lgp == NULL) + return NULL; + + i_size = i_size_read(ino); + + lgp->args.minlength = PAGE_CACHE_SIZE; + if (lgp->args.minlength > range->length) + lgp->args.minlength = range->length; + if (range->iomode == IOMODE_READ) { + if (range->offset >= i_size) + lgp->args.minlength = 0; + else if (i_size - range->offset < lgp->args.minlength) + lgp->args.minlength = i_size - range->offset; + } + lgp->args.maxcount = PNFS_LAYOUT_MAXSIZE; + lgp->args.range = *range; + lgp->args.type = server->pnfs_curr_ld->id; + lgp->args.inode = ino; + lgp->args.ctx = get_nfs_open_context(ctx); + lgp->gfp_flags = gfp_flags; + lgp->cred = lo->plh_lc_cred; - lgp->args.minlength = PAGE_CACHE_SIZE; - if (lgp->args.minlength > range->length) - lgp->args.minlength = range->length; - if (range->iomode == IOMODE_READ) { - if (range->offset >= i_size) - lgp->args.minlength = 0; - else if (i_size - range->offset < lgp->args.minlength) - lgp->args.minlength = i_size - range->offset; - } - lgp->args.maxcount = PNFS_LAYOUT_MAXSIZE; - lgp->args.range = *range; - lgp->args.type = server->pnfs_curr_ld->id; - lgp->args.inode = ino; - lgp->args.ctx = get_nfs_open_context(ctx); - lgp->gfp_flags = gfp_flags; - lgp->cred = lo->plh_lc_cred; + lseg = nfs4_proc_layoutget(lgp, gfp_flags); + } while (lseg == ERR_PTR(-EAGAIN)); - /* Synchronously retrieve layout information from server and - * store in lseg. - */ - lseg = nfs4_proc_layoutget(lgp, gfp_flags); if (IS_ERR(lseg)) { switch (PTR_ERR(lseg)) { case -ENOMEM: @@ -1687,6 +1692,7 @@ pnfs_layout_process(struct nfs4_layoutge /* existing state ID, make sure the sequence number matches. */ if (pnfs_layout_stateid_blocked(lo, &res->stateid)) { dprintk("%s forget reply due to sequence\n", __func__); + status = -EAGAIN; goto out_forget_reply; } pnfs_set_layout_stateid(lo, &res->stateid, false); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/