afs: Fix mounting of backup volumes

In theory the AFS_VLSF_BACKVOL flag for a server in a vldb entry
would indicate the presence of a backup volume on that server.

In practice however, this flag is never set, and the presence of
a backup volume is implied by the entry having AFS_VLF_BACKEXISTS set,
for the server that hosts the read-write volume (has AFS_VLSF_RWVOL).

Signed-off-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>

1 files changed, 10 insertions, 9 deletions

diff --git a/fs/afs/vlclient.c b/fs/afs/vlclient.c
index 1ed7e2fd2f35..c3b740813fc7 100644
--- a/fs/afs/vlclient.c
+++ b/fs/afs/vlclient.c
@@ -23,7 +23,7 @@ static int afs_deliver_vl_get_entry_by_name_u(struct afs_call *call)
         struct afs_uvldbentry__xdr *uvldb;
         struct afs_vldb_entry *entry;
         bool new_only = false;
-        u32 tmp, nr_servers;
+        u32 tmp, nr_servers, vlflags;
         int i, ret;
 
         _enter("");
@@ -55,6 +55,7 @@ static int afs_deliver_vl_get_entry_by_name_u(struct afs_call *call)
                         new_only = true;
         }
 
+        vlflags = ntohl(uvldb->flags);
         for (i = 0; i < nr_servers; i++) {
                 struct afs_uuid__xdr *xdr;
                 struct afs_uuid *uuid;
@@ -64,12 +65,13 @@ static int afs_deliver_vl_get_entry_by_name_u(struct afs_call *call)
                 if (tmp & AFS_VLSF_DONTUSE ||
                     (new_only && !(tmp & AFS_VLSF_NEWREPSITE)))
                         continue;
-                if (tmp & AFS_VLSF_RWVOL)
+                if (tmp & AFS_VLSF_RWVOL) {
                         entry->fs_mask[i] |= AFS_VOL_VTM_RW;
+                        if (vlflags & AFS_VLF_BACKEXISTS)
+                                entry->fs_mask[i] |= AFS_VOL_VTM_BAK;
+                }
                 if (tmp & AFS_VLSF_ROVOL)
                         entry->fs_mask[i] |= AFS_VOL_VTM_RO;
-                if (tmp & AFS_VLSF_BACKVOL)
-                        entry->fs_mask[i] |= AFS_VOL_VTM_BAK;
                 if (!entry->fs_mask[i])
                         continue;
 
@@ -89,15 +91,14 @@ static int afs_deliver_vl_get_entry_by_name_u(struct afs_call *call)
         for (i = 0; i < AFS_MAXTYPES; i++)
                 entry->vid[i] = ntohl(uvldb->volumeId[i]);
 
-        tmp = ntohl(uvldb->flags);
-        if (tmp & AFS_VLF_RWEXISTS)
+        if (vlflags & AFS_VLF_RWEXISTS)
                 __set_bit(AFS_VLDB_HAS_RW, &entry->flags);
-        if (tmp & AFS_VLF_ROEXISTS)
+        if (vlflags & AFS_VLF_ROEXISTS)
                 __set_bit(AFS_VLDB_HAS_RO, &entry->flags);
-        if (tmp & AFS_VLF_BACKEXISTS)
+        if (vlflags & AFS_VLF_BACKEXISTS)
                 __set_bit(AFS_VLDB_HAS_BAK, &entry->flags);
 
-        if (!(tmp & (AFS_VLF_RWEXISTS | AFS_VLF_ROEXISTS | AFS_VLF_BACKEXISTS))) {
+        if (!(vlflags & (AFS_VLF_RWEXISTS | AFS_VLF_ROEXISTS | AFS_VLF_BACKEXISTS))) {
                 entry->error = -ENOMEDIUM;
                 __set_bit(AFS_VLDB_QUERY_ERROR, &entry->flags);
         }