NFSv4.1: use struct nfs_client to qualify deviceid

deviceids are unique per server, per layout type.
Therefore, in the global cache in the files layout driver
deviceids from different servers may clash so we need
to qualify them with a struct nfs_client that represents
the nfs server that returned the deviceid.

Introduced in 2.6.39 commit ea8eecdd
"NFSv4.1 move deviceid cache to filelayout driver"

Signed-off-by: Benny Halevy <bhalevy@panasas.com>

1 files changed, 4 insertions, 5 deletions

diff --git a/fs/nfs/nfs4filelayoutdev.c b/fs/nfs/nfs4filelayoutdev.c
index db07c7af1395..42e326637271 100644
--- a/fs/nfs/nfs4filelayoutdev.c
+++ b/fs/nfs/nfs4filelayoutdev.c
@@ -431,7 +431,7 @@ decode_device(struct inode *ino, struct pnfs_device *pdev, gfp_t gfp_flags)
         dsaddr->stripe_indices = stripe_indices;
         stripe_indices = NULL;
         dsaddr->ds_num = num;
-
+        dsaddr->nfs_client = NFS_SERVER(ino)->nfs_client;
         memcpy(&dsaddr->deviceid, &pdev->dev_id, sizeof(pdev->dev_id));
 
         for (i = 0; i < dsaddr->ds_num; i++) {
@@ -516,7 +516,7 @@ decode_and_add_device(struct inode *inode, struct pnfs_device *dev, gfp_t gfp_fl
         }
 
         spin_lock(&filelayout_deviceid_lock);
-        d = nfs4_fl_find_get_deviceid(&new->deviceid);
+        d = nfs4_fl_find_get_deviceid(new->nfs_client, &new->deviceid);
         if (d) {
                 spin_unlock(&filelayout_deviceid_lock);
                 nfs4_fl_free_deviceid(new);
@@ -610,16 +610,15 @@ nfs4_fl_put_deviceid(struct nfs4_file_layout_dsaddr *dsaddr)
 }
 
 struct nfs4_file_layout_dsaddr *
-nfs4_fl_find_get_deviceid(struct nfs4_deviceid *id)
+nfs4_fl_find_get_deviceid(struct nfs_client *clp, struct nfs4_deviceid *id)
 {
         struct nfs4_file_layout_dsaddr *d;
         struct hlist_node *n;
         long hash = nfs4_fl_deviceid_hash(id);
 
-
         rcu_read_lock();
         hlist_for_each_entry_rcu(d, n, &filelayout_deviceid_cache[hash], node) {
-                if (!memcmp(&d->deviceid, id, sizeof(*id))) {
+                if (d->nfs_client == clp && !memcmp(&d->deviceid, id, sizeof(*id))) {
                         if (!atomic_inc_not_zero(&d->ref))
                                 goto fail;
                         rcu_read_unlock();