[PATCH] NOMMU: Implement /proc/pid/maps for NOMMU
Implement /proc/pid/maps for NOMMU by reading the vm_area_list attached to
current->mm->context.vmlist.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/fs/proc/task_nommu.c b/fs/proc/task_nommu.c
index 4616ed5..091aa8e 100644
--- a/fs/proc/task_nommu.c
+++ b/fs/proc/task_nommu.c
@@ -138,25 +138,63 @@
}
/*
- * Albert D. Cahalan suggested to fake entries for the traditional
- * sections here. This might be worth investigating.
+ * display mapping lines for a particular process's /proc/pid/maps
*/
-static int show_map(struct seq_file *m, void *v)
+static int show_map(struct seq_file *m, void *_vml)
{
- return 0;
+ struct vm_list_struct *vml = _vml;
+ return nommu_vma_show(m, vml->vma);
}
+
static void *m_start(struct seq_file *m, loff_t *pos)
{
+ struct proc_maps_private *priv = m->private;
+ struct vm_list_struct *vml;
+ struct mm_struct *mm;
+ loff_t n = *pos;
+
+ /* pin the task and mm whilst we play with them */
+ priv->task = get_pid_task(priv->pid, PIDTYPE_PID);
+ if (!priv->task)
+ return NULL;
+
+ mm = get_task_mm(priv->task);
+ if (!mm) {
+ put_task_struct(priv->task);
+ priv->task = NULL;
+ return NULL;
+ }
+
+ down_read(&mm->mmap_sem);
+
+ /* start from the Nth VMA */
+ for (vml = mm->context.vmlist; vml; vml = vml->next)
+ if (n-- == 0)
+ return vml;
return NULL;
}
-static void m_stop(struct seq_file *m, void *v)
+
+static void m_stop(struct seq_file *m, void *_vml)
{
+ struct proc_maps_private *priv = m->private;
+
+ if (priv->task) {
+ struct mm_struct *mm = priv->task->mm;
+ up_read(&mm->mmap_sem);
+ mmput(mm);
+ put_task_struct(priv->task);
+ }
}
-static void *m_next(struct seq_file *m, void *v, loff_t *pos)
+
+static void *m_next(struct seq_file *m, void *_vml, loff_t *pos)
{
- return NULL;
+ struct vm_list_struct *vml = _vml;
+
+ (*pos)++;
+ return vml ? vml->next : NULL;
}
-static struct seq_operations proc_pid_maps_op = {
+
+static struct seq_operations proc_pid_maps_ops = {
.start = m_start,
.next = m_next,
.stop = m_stop,
@@ -165,11 +203,19 @@
static int maps_open(struct inode *inode, struct file *file)
{
- int ret;
- ret = seq_open(file, &proc_pid_maps_op);
- if (!ret) {
- struct seq_file *m = file->private_data;
- m->private = NULL;
+ struct proc_maps_private *priv;
+ int ret = -ENOMEM;
+
+ priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+ if (priv) {
+ priv->pid = proc_pid(inode);
+ ret = seq_open(file, &proc_pid_maps_ops);
+ if (!ret) {
+ struct seq_file *m = file->private_data;
+ m->private = priv;
+ } else {
+ kfree(priv);
+ }
}
return ret;
}
@@ -178,6 +224,6 @@
.open = maps_open,
.read = seq_read,
.llseek = seq_lseek,
- .release = seq_release,
+ .release = seq_release_private,
};