pid namespaces: prepare proc_flust_task() to flush entries from multiple proc trees

[safe/jmp/linux-2.6] / fs / proc / base.c

diff --git a/fs/proc/base.c b/fs/proc/base.c
index 6afca09..36983e7 100644 (file)
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -74,6 +74,7 @@
 #include <linux/nsproxy.h>
 #include <linux/oom.h>
 #include <linux/elf.h>
+#include <linux/pid_namespace.h>
 #include "internal.h"
 
 /* NOTE:
@@ -2204,27 +2205,27 @@ static const struct inode_operations proc_tgid_base_inode_operations = {
  *       that no dcache entries will exist at process exit time it
  *       just makes it very unlikely that any will persist.
  */
-void proc_flush_task(struct task_struct *task)
+static void proc_flush_task_mnt(struct vfsmount *mnt, pid_t pid, pid_t tgid)
 {
        struct dentry *dentry, *leader, *dir;
        char buf[PROC_NUMBUF];
        struct qstr name;
 
        name.name = buf;
-       name.len = snprintf(buf, sizeof(buf), "%d", task->pid);
-       dentry = d_hash_and_lookup(proc_mnt->mnt_root, &name);
+       name.len = snprintf(buf, sizeof(buf), "%d", pid);
+       dentry = d_hash_and_lookup(mnt->mnt_root, &name);
        if (dentry) {
                shrink_dcache_parent(dentry);
                d_drop(dentry);
                dput(dentry);
        }
 
-       if (thread_group_leader(task))
+       if (tgid == 0)
                goto out;
 
        name.name = buf;
-       name.len = snprintf(buf, sizeof(buf), "%d", task->tgid);
-       leader = d_hash_and_lookup(proc_mnt->mnt_root, &name);
+       name.len = snprintf(buf, sizeof(buf), "%d", tgid);
+       leader = d_hash_and_lookup(mnt->mnt_root, &name);
        if (!leader)
                goto out;
 
@@ -2235,7 +2236,7 @@ void proc_flush_task(struct task_struct *task)
                goto out_put_leader;
 
        name.name = buf;
-       name.len = snprintf(buf, sizeof(buf), "%d", task->pid);
+       name.len = snprintf(buf, sizeof(buf), "%d", pid);
        dentry = d_hash_and_lookup(dir, &name);
        if (dentry) {
                shrink_dcache_parent(dentry);
@@ -2250,6 +2251,18 @@ out:
        return;
 }
 
+/*
+ * when flushing dentries from proc one need to flush them from global
+ * proc (proc_mnt) and from all the namespaces' procs this task was seen
+ * in. this call is supposed to make all this job.
+ */
+
+void proc_flush_task(struct task_struct *task)
+{
+       proc_flush_task_mnt(proc_mnt, task->pid,
+                       thread_group_leader(task) ? 0 : task->tgid);
+}
+
 static struct dentry *proc_pid_instantiate(struct inode *dir,
                                           struct dentry * dentry,
                                           struct task_struct *task, const void *ptr)