[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>
This commit is contained in:
David Howells 2006-09-27 01:50:19 -07:00 committed by Linus Torvalds
parent d00c7b9937
commit dbf8685c8e
5 changed files with 80 additions and 20 deletions

View File

@ -116,6 +116,9 @@ FURTHER NOTES ON NO-MMU MMAP
(*) A list of all the mappings on the system is visible through /proc/maps in
no-MMU mode.
(*) A list of all the mappings in use by a process is visible through
/proc/<pid>/maps in no-MMU mode.
(*) Supplying MAP_FIXED or a requesting a particular mapping address will
result in an error.

View File

@ -28,6 +28,7 @@ do { \
(vmi)->largest_chunk = 0; \
} while(0)
extern int nommu_vma_show(struct seq_file *, struct vm_area_struct *);
#endif
extern void create_seq_entry(char *name, mode_t mode, const struct file_operations *f);

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@ -33,19 +33,15 @@
#include "internal.h"
/*
* display a list of all the VMAs the kernel knows about
* - nommu kernals have a single flat list
* display a single VMA to a sequenced file
*/
static int nommu_vma_list_show(struct seq_file *m, void *v)
int nommu_vma_show(struct seq_file *m, struct vm_area_struct *vma)
{
struct vm_area_struct *vma;
unsigned long ino = 0;
struct file *file;
dev_t dev = 0;
int flags, len;
vma = rb_entry((struct rb_node *) v, struct vm_area_struct, vm_rb);
flags = vma->vm_flags;
file = vma->vm_file;
@ -78,6 +74,18 @@ static int nommu_vma_list_show(struct seq_file *m, void *v)
return 0;
}
/*
* display a list of all the VMAs the kernel knows about
* - nommu kernals have a single flat list
*/
static int nommu_vma_list_show(struct seq_file *m, void *v)
{
struct vm_area_struct *vma;
vma = rb_entry((struct rb_node *) v, struct vm_area_struct, vm_rb);
return nommu_vma_show(m, vma);
}
static void *nommu_vma_list_start(struct seq_file *m, loff_t *_pos)
{
struct rb_node *_rb;

View File

@ -138,25 +138,63 @@ int proc_exe_link(struct inode *inode, struct dentry **dentry, struct vfsmount *
}
/*
* 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 struct seq_operations proc_pid_maps_op = {
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 @@ struct file_operations proc_maps_operations = {
.open = maps_open,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release,
.release = seq_release_private,
};

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@ -268,7 +268,9 @@ static inline struct proc_dir_entry *PDE(const struct inode *inode)
struct proc_maps_private {
struct pid *pid;
struct task_struct *task;
#ifdef CONFIG_MMU
struct vm_area_struct *tail_vma;
#endif
};
#endif /* _LINUX_PROC_FS_H */