Return-Path: linux-nfs-owner@vger.kernel.org Received: from mx2.netapp.com ([216.240.18.37]:37882 "EHLO mx2.netapp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755987Ab2BCUpp (ORCPT ); Fri, 3 Feb 2012 15:45:45 -0500 From: Weston Andros Adamson To: Trond.Myklebust@netapp.com Cc: linux-nfs@vger.kernel.org, Weston Andros Adamson Subject: [PATCH] NFS: Fix comparison between DS address lists Date: Fri, 3 Feb 2012 15:45:40 -0500 Message-Id: <1328301940-478-1-git-send-email-dros@netapp.com> Sender: linux-nfs-owner@vger.kernel.org List-ID: data_server_cache entries should only be treated as the same if the address list hasn't changed. A new entry will be made when an MDS changes an address list (as seen by GETDEVINFO). The old entry will be freed once all references are gone. Signed-off-by: Weston Andros Adamson --- fs/nfs/nfs4filelayoutdev.c | 71 +++++++++++++++----------------------------- 1 files changed, 24 insertions(+), 47 deletions(-) diff --git a/fs/nfs/nfs4filelayoutdev.c b/fs/nfs/nfs4filelayoutdev.c index 6eb59b0..420e748 100644 --- a/fs/nfs/nfs4filelayoutdev.c +++ b/fs/nfs/nfs4filelayoutdev.c @@ -108,58 +108,40 @@ same_sockaddr(struct sockaddr *addr1, struct sockaddr *addr2) return false; } -/* - * Lookup DS by addresses. The first matching address returns true. - * nfs4_ds_cache_lock is held - */ -static struct nfs4_pnfs_ds * -_data_server_lookup_locked(struct list_head *dsaddrs) +bool +_same_data_server_addrs_locked(const struct list_head *dsaddrs1, + const struct list_head *dsaddrs2) { - struct nfs4_pnfs_ds *ds; struct nfs4_pnfs_ds_addr *da1, *da2; - list_for_each_entry(da1, dsaddrs, da_node) { - list_for_each_entry(ds, &nfs4_data_server_cache, ds_node) { - list_for_each_entry(da2, &ds->ds_addrs, da_node) { - if (same_sockaddr( - (struct sockaddr *)&da1->da_addr, - (struct sockaddr *)&da2->da_addr)) - return ds; - } - } + /* step through both lists, comparing as we go */ + for (da1 = list_first_entry(dsaddrs1, typeof(*da1), da_node), + da2 = list_first_entry(dsaddrs2, typeof(*da2), da_node); + da1 != NULL && da2 != NULL; + da1 = list_entry(da1->da_node.next, typeof(*da1), da_node), + da2 = list_entry(da2->da_node.next, typeof(*da2), da_node)) { + if (!same_sockaddr((struct sockaddr *)&da1->da_addr, + (struct sockaddr *)&da2->da_addr)) + return false; } - return NULL; + if (da1 == NULL && da2 == NULL) + return true; + + return false; } /* - * Compare two lists of addresses. + * Lookup DS by addresses. nfs4_ds_cache_lock is held */ -static bool -_data_server_match_all_addrs_locked(struct list_head *dsaddrs1, - struct list_head *dsaddrs2) +static struct nfs4_pnfs_ds * +_data_server_lookup_locked(const struct list_head *dsaddrs) { - struct nfs4_pnfs_ds_addr *da1, *da2; - size_t count1 = 0, - count2 = 0; - - list_for_each_entry(da1, dsaddrs1, da_node) - count1++; - - list_for_each_entry(da2, dsaddrs2, da_node) { - bool found = false; - count2++; - list_for_each_entry(da1, dsaddrs1, da_node) { - if (same_sockaddr((struct sockaddr *)&da1->da_addr, - (struct sockaddr *)&da2->da_addr)) { - found = true; - break; - } - } - if (!found) - return false; - } + struct nfs4_pnfs_ds *ds; - return (count1 == count2); + list_for_each_entry(ds, &nfs4_data_server_cache, ds_node) + if (_same_data_server_addrs_locked(&ds->ds_addrs, dsaddrs)) + return ds; + return NULL; } /* @@ -356,11 +338,6 @@ nfs4_pnfs_ds_add(struct list_head *dsaddrs, gfp_t gfp_flags) dprintk("%s add new data server %s\n", __func__, ds->ds_remotestr); } else { - if (!_data_server_match_all_addrs_locked(&tmp_ds->ds_addrs, - dsaddrs)) { - dprintk("%s: multipath address mismatch: %s != %s", - __func__, tmp_ds->ds_remotestr, remotestr); - } kfree(remotestr); kfree(ds); atomic_inc(&tmp_ds->ds_count); -- 1.7.4.4