Merge branch 'for-5.1/nfit/ars' into libnvdimm-for-next

Merge several updates to the ARS implementation. Highlights include:

* Support retrieval of short-ARS results if the ARS state is "requires
  continuation", and even if the "no_init_ars" module parameter is
  specified.
* Allow busy-polling of the kernel ARS state by allowing root to reset
  the exponential back-off timer.
* Filter potentially stale ARS results by tracking query-ARS relative to
  the previous start-ARS.

3 files changed, 24 insertions, 1 deletions

diff --git a/fs/proc/generic.c b/fs/proc/generic.c
index 8ae109429a88..e39bac94dead 100644
--- a/fs/proc/generic.c
+++ b/fs/proc/generic.c
@@ -256,7 +256,7 @@ struct dentry *proc_lookup_de(struct inode *dir, struct dentry *dentry,
                 inode = proc_get_inode(dir->i_sb, de);
                 if (!inode)
                         return ERR_PTR(-ENOMEM);
-                d_set_d_op(dentry, &proc_misc_dentry_ops);
+                d_set_d_op(dentry, de->proc_dops);
                 return d_splice_alias(inode, dentry);
         }
         read_unlock(&proc_subdir_lock);
@@ -429,6 +429,8 @@ static struct proc_dir_entry *__proc_create(struct proc_dir_entry **parent,
         INIT_LIST_HEAD(&ent->pde_openers);
         proc_set_user(ent, (*parent)->uid, (*parent)->gid);
 
+        ent->proc_dops = &proc_misc_dentry_ops;
+
 out:
         return ent;
 }
diff --git a/fs/proc/internal.h b/fs/proc/internal.h
index 5185d7f6a51e..95b14196f284 100644
--- a/fs/proc/internal.h
+++ b/fs/proc/internal.h
@@ -44,6 +44,7 @@ struct proc_dir_entry {
         struct completion *pde_unload_completion;
         const struct inode_operations *proc_iops;
         const struct file_operations *proc_fops;
+        const struct dentry_operations *proc_dops;
         union {
                 const struct seq_operations *seq_ops;
                 int (*single_show)(struct seq_file *, void *);
diff --git a/fs/proc/proc_net.c b/fs/proc/proc_net.c
index d5e0fcb3439e..a7b12435519e 100644
--- a/fs/proc/proc_net.c
+++ b/fs/proc/proc_net.c
@@ -38,6 +38,22 @@ static struct net *get_proc_net(const struct inode *inode)
         return maybe_get_net(PDE_NET(PDE(inode)));
 }
 
+static int proc_net_d_revalidate(struct dentry *dentry, unsigned int flags)
+{
+        return 0;
+}
+
+static const struct dentry_operations proc_net_dentry_ops = {
+        .d_revalidate   = proc_net_d_revalidate,
+        .d_delete       = always_delete_dentry,
+};
+
+static void pde_force_lookup(struct proc_dir_entry *pde)
+{
+        /* /proc/net/ entries can be changed under us by setns(CLONE_NEWNET) */
+        pde->proc_dops = &proc_net_dentry_ops;
+}
+
 static int seq_open_net(struct inode *inode, struct file *file)
 {
         unsigned int state_size = PDE(inode)->state_size;
@@ -90,6 +106,7 @@ struct proc_dir_entry *proc_create_net_data(const char *name, umode_t mode,
         p = proc_create_reg(name, mode, &parent, data);
         if (!p)
                 return NULL;
+        pde_force_lookup(p);
         p->proc_fops = &proc_net_seq_fops;
         p->seq_ops = ops;
         p->state_size = state_size;
@@ -133,6 +150,7 @@ struct proc_dir_entry *proc_create_net_data_write(const char *name, umode_t mode
         p = proc_create_reg(name, mode, &parent, data);
         if (!p)
                 return NULL;
+        pde_force_lookup(p);
         p->proc_fops = &proc_net_seq_fops;
         p->seq_ops = ops;
         p->state_size = state_size;
@@ -181,6 +199,7 @@ struct proc_dir_entry *proc_create_net_single(const char *name, umode_t mode,
         p = proc_create_reg(name, mode, &parent, data);
         if (!p)
                 return NULL;
+        pde_force_lookup(p);
         p->proc_fops = &proc_net_single_fops;
         p->single_show = show;
         return proc_register(parent, p);
@@ -223,6 +242,7 @@ struct proc_dir_entry *proc_create_net_single_write(const char *name, umode_t mo
         p = proc_create_reg(name, mode, &parent, data);
         if (!p)
                 return NULL;
+        pde_force_lookup(p);
         p->proc_fops = &proc_net_single_fops;
         p->single_show = show;
         p->write = write;