NFS: Fix comparison between DS address lists
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 <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/nfs4filelayoutdev.c b/fs/nfs/nfs4filelayoutdev.c
index 80fce8d..41677f0 100644
--- a/fs/nfs/nfs4filelayoutdev.c
+++ b/fs/nfs/nfs4filelayoutdev.c
@@ -108,58 +108,40 @@
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;
+ struct nfs4_pnfs_ds *ds;
- 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;
- }
-
- 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 @@
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);