NFSv4: Return NFS4ERR_DELAY when a layout recall fails due to igrab()

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

diff --git a/fs/nfs/callback_proc.c b/fs/nfs/callback_proc.c
index eacd09d..3a49bb1 100644 (file)
--- a/fs/nfs/callback_proc.c
+++ b/fs/nfs/callback_proc.c
@@ -128,7 +128,6 @@ static struct inode *nfs_layout_find_inode_by_stateid(struct nfs_client *clp,
        struct inode *inode;
        struct pnfs_layout_hdr *lo;
 
-restart:
        list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
                list_for_each_entry(lo, &server->layouts, plh_layouts) {
                        if (stateid != NULL &&
@@ -136,20 +135,20 @@ restart:
                                continue;
                        inode = igrab(lo->plh_inode);
                        if (!inode)
-                               continue;
+                               return ERR_PTR(-EAGAIN);
                        if (!nfs_sb_active(inode->i_sb)) {
                                rcu_read_unlock();
                                spin_unlock(&clp->cl_lock);
                                iput(inode);
                                spin_lock(&clp->cl_lock);
                                rcu_read_lock();
-                               goto restart;
+                               return ERR_PTR(-EAGAIN);
                        }
                        return inode;
                }
        }
 
-       return NULL;
+       return ERR_PTR(-ENOENT);
 }
 
 /*
@@ -166,7 +165,6 @@ static struct inode *nfs_layout_find_inode_by_fh(struct nfs_client *clp,
        struct inode *inode;
        struct pnfs_layout_hdr *lo;
 
-restart:
        list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
                list_for_each_entry(lo, &server->layouts, plh_layouts) {
                        nfsi = NFS_I(lo->plh_inode);
@@ -176,20 +174,20 @@ restart:
                                continue;
                        inode = igrab(lo->plh_inode);
                        if (!inode)
-                               continue;
+                               return ERR_PTR(-EAGAIN);
                        if (!nfs_sb_active(inode->i_sb)) {
                                rcu_read_unlock();
                                spin_unlock(&clp->cl_lock);
                                iput(inode);
                                spin_lock(&clp->cl_lock);
                                rcu_read_lock();
-                               goto restart;
+                               return ERR_PTR(-EAGAIN);
                        }
                        return inode;
                }
        }
 
-       return NULL;
+       return ERR_PTR(-ENOENT);
 }
 
 static struct inode *nfs_layout_find_inode(struct nfs_client *clp,
@@ -201,7 +199,7 @@ static struct inode *nfs_layout_find_inode(struct nfs_client *clp,
        spin_lock(&clp->cl_lock);
        rcu_read_lock();
        inode = nfs_layout_find_inode_by_stateid(clp, stateid);
-       if (!inode)
+       if (inode == ERR_PTR(-ENOENT))
                inode = nfs_layout_find_inode_by_fh(clp, fh);
        rcu_read_unlock();
        spin_unlock(&clp->cl_lock);
@@ -256,8 +254,11 @@ static u32 initiate_file_draining(struct nfs_client *clp,
        LIST_HEAD(free_me_list);
 
        ino = nfs_layout_find_inode(clp, &args->cbl_fh, &args->cbl_stateid);
-       if (!ino)
-               goto out;
+       if (IS_ERR(ino)) {
+               if (ino == ERR_PTR(-EAGAIN))
+                       rv = NFS4ERR_DELAY;
+               goto out_noput;
+       }
 
        pnfs_layoutcommit_inode(ino, false);
 
@@ -303,9 +304,10 @@ unlock:
        nfs_commit_inode(ino, 0);
        pnfs_put_layout_hdr(lo);
 out:
+       nfs_iput_and_deactive(ino);
+out_noput:
        trace_nfs4_cb_layoutrecall_file(clp, &args->cbl_fh, ino,
                        &args->cbl_stateid, -rv);
-       nfs_iput_and_deactive(ino);
        return rv;
 }