locks/nfsd: allocate file lock outside of spinlock

As suggested by Christoph Hellwig, this moves allocation
of new file locks out of generic_setlease into the
callers, nfs4_open_delegation and fcntl_setlease in order
to allow GFP_KERNEL allocations when lock_flocks has
become a spinlock.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: J. Bruce Fields <bfields@redhat.com>

1 files changed, 15 insertions, 11 deletions

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 9019e8ec9dc8..56347e0ac88d 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -2614,7 +2614,7 @@ nfs4_open_delegation(struct svc_fh *fh, struct nfsd4_open *open, struct nfs4_sta
         struct nfs4_delegation *dp;
         struct nfs4_stateowner *sop = stp->st_stateowner;
         int cb_up = atomic_read(&sop->so_client->cl_cb_set);
-        struct file_lock fl, *flp = &fl;
+        struct file_lock *fl;
         int status, flag = 0;
 
         flag = NFS4_OPEN_DELEGATE_NONE;
@@ -2648,20 +2648,24 @@ nfs4_open_delegation(struct svc_fh *fh, struct nfsd4_open *open, struct nfs4_sta
                 flag = NFS4_OPEN_DELEGATE_NONE;
                 goto out;
         }
-        locks_init_lock(&fl);
-        fl.fl_lmops = &nfsd_lease_mng_ops;
-        fl.fl_flags = FL_LEASE;
-        fl.fl_type = flag == NFS4_OPEN_DELEGATE_READ? F_RDLCK: F_WRLCK;
-        fl.fl_end = OFFSET_MAX;
-        fl.fl_owner =  (fl_owner_t)dp;
-        fl.fl_file = find_readable_file(stp->st_file);
-        BUG_ON(!fl.fl_file);
-        fl.fl_pid = current->tgid;
+        status = -ENOMEM;
+        fl = locks_alloc_lock();
+        if (!fl)
+                goto out;
+        locks_init_lock(fl);
+        fl->fl_lmops = &nfsd_lease_mng_ops;
+        fl->fl_flags = FL_LEASE;
+        fl->fl_type = flag == NFS4_OPEN_DELEGATE_READ? F_RDLCK: F_WRLCK;
+        fl->fl_end = OFFSET_MAX;
+        fl->fl_owner =  (fl_owner_t)dp;
+        fl->fl_file = find_readable_file(stp->st_file);
+        BUG_ON(!fl->fl_file);
+        fl->fl_pid = current->tgid;
 
         /* vfs_setlease checks to see if delegation should be handed out.
          * the lock_manager callbacks fl_mylease and fl_change are used
          */
-        if ((status = vfs_setlease(fl.fl_file, fl.fl_type, &flp))) {
+        if ((status = vfs_setlease(fl->fl_file, fl->fl_type, &fl))) {
                 dprintk("NFSD: setlease failed [%d], no delegation\n", status);
                 unhash_delegation(dp);
                 flag = NFS4_OPEN_DELEGATE_NONE;