proc.c

linux 内核源代码

infault:
	kfree(kbuf);
nomem:
	_leave(" = %d", ret);
	return ret;
}

/*
 * initialise /proc/fs/afs/<cell>/
 */
int afs_proc_cell_setup(struct afs_cell *cell)
{
	struct proc_dir_entry *p;

	_enter("%p{%s}", cell, cell->name);

	cell->proc_dir = proc_mkdir(cell->name, proc_afs);
	if (!cell->proc_dir)
		goto error_dir;

	p = create_proc_entry("servers", 0, cell->proc_dir);
	if (!p)
		goto error_servers;
	p->proc_fops = &afs_proc_cell_servers_fops;
	p->owner = THIS_MODULE;
	p->data = cell;

	p = create_proc_entry("vlservers", 0, cell->proc_dir);
	if (!p)
		goto error_vlservers;
	p->proc_fops = &afs_proc_cell_vlservers_fops;
	p->owner = THIS_MODULE;
	p->data = cell;

	p = create_proc_entry("volumes", 0, cell->proc_dir);
	if (!p)
		goto error_volumes;
	p->proc_fops = &afs_proc_cell_volumes_fops;
	p->owner = THIS_MODULE;
	p->data = cell;

	_leave(" = 0");
	return 0;

error_volumes:
	remove_proc_entry("vlservers", cell->proc_dir);
error_vlservers:
	remove_proc_entry("servers", cell->proc_dir);
error_servers:
	remove_proc_entry(cell->name, proc_afs);
error_dir:
	_leave(" = -ENOMEM");
	return -ENOMEM;
}

/*
 * remove /proc/fs/afs/<cell>/
 */
void afs_proc_cell_remove(struct afs_cell *cell)
{
	_enter("");

	remove_proc_entry("volumes", cell->proc_dir);
	remove_proc_entry("vlservers", cell->proc_dir);
	remove_proc_entry("servers", cell->proc_dir);
	remove_proc_entry(cell->name, proc_afs);

	_leave("");
}

/*
 * open "/proc/fs/afs/<cell>/volumes" which provides a summary of extant cells
 */
static int afs_proc_cell_volumes_open(struct inode *inode, struct file *file)
{
	struct afs_cell *cell;
	struct seq_file *m;
	int ret;

	cell = PDE(inode)->data;
	if (!cell)
		return -ENOENT;

	ret = seq_open(file, &afs_proc_cell_volumes_ops);
	if (ret < 0)
		return ret;

	m = file->private_data;
	m->private = cell;

	return 0;
}

/*
 * close the file and release the ref to the cell
 */
static int afs_proc_cell_volumes_release(struct inode *inode, struct file *file)
{
	return seq_release(inode, file);
}

/*
 * set up the iterator to start reading from the cells list and return the
 * first item
 */
static void *afs_proc_cell_volumes_start(struct seq_file *m, loff_t *_pos)
{
	struct afs_cell *cell = m->private;

	_enter("cell=%p pos=%Ld", cell, *_pos);

	/* lock the list against modification */
	down_read(&cell->vl_sem);
	return seq_list_start_head(&cell->vl_list, *_pos);
}

/*
 * move to next cell in cells list
 */
static void *afs_proc_cell_volumes_next(struct seq_file *p, void *v,
					loff_t *_pos)
{
	struct afs_cell *cell = p->private;

	_enter("cell=%p pos=%Ld", cell, *_pos);
	return seq_list_next(v, &cell->vl_list, _pos);
}

/*
 * clean up after reading from the cells list
 */
static void afs_proc_cell_volumes_stop(struct seq_file *p, void *v)
{
	struct afs_cell *cell = p->private;

	up_read(&cell->vl_sem);
}

static const char afs_vlocation_states[][4] = {
	[AFS_VL_NEW]			= "New",
	[AFS_VL_CREATING]		= "Crt",
	[AFS_VL_VALID]			= "Val",
	[AFS_VL_NO_VOLUME]		= "NoV",
	[AFS_VL_UPDATING]		= "Upd",
	[AFS_VL_VOLUME_DELETED]		= "Del",
	[AFS_VL_UNCERTAIN]		= "Unc",
};

/*
 * display a header line followed by a load of volume lines
 */
static int afs_proc_cell_volumes_show(struct seq_file *m, void *v)
{
	struct afs_cell *cell = m->private;
	struct afs_vlocation *vlocation =
		list_entry(v, struct afs_vlocation, link);

	/* display header on line 1 */
	if (v == &cell->vl_list) {
		seq_puts(m, "USE STT VLID[0]  VLID[1]  VLID[2]  NAME\n");
		return 0;
	}

	/* display one cell per line on subsequent lines */
	seq_printf(m, "%3d %s %08x %08x %08x %s\n",
		   atomic_read(&vlocation->usage),
		   afs_vlocation_states[vlocation->state],
		   vlocation->vldb.vid[0],
		   vlocation->vldb.vid[1],
		   vlocation->vldb.vid[2],
		   vlocation->vldb.name);

	return 0;
}

/*
 * open "/proc/fs/afs/<cell>/vlservers" which provides a list of volume
 * location server
 */
static int afs_proc_cell_vlservers_open(struct inode *inode, struct file *file)
{
	struct afs_cell *cell;
	struct seq_file *m;
	int ret;

	cell = PDE(inode)->data;
	if (!cell)
		return -ENOENT;

	ret = seq_open(file, &afs_proc_cell_vlservers_ops);
	if (ret<0)
		return ret;

	m = file->private_data;
	m->private = cell;

	return 0;
}

/*
 * close the file and release the ref to the cell
 */
static int afs_proc_cell_vlservers_release(struct inode *inode,
					   struct file *file)
{
	return seq_release(inode, file);
}

/*
 * set up the iterator to start reading from the cells list and return the
 * first item
 */
static void *afs_proc_cell_vlservers_start(struct seq_file *m, loff_t *_pos)
{
	struct afs_cell *cell = m->private;
	loff_t pos = *_pos;

	_enter("cell=%p pos=%Ld", cell, *_pos);

	/* lock the list against modification */
	down_read(&cell->vl_sem);

	/* allow for the header line */
	if (!pos)
		return (void *) 1;
	pos--;

	if (pos >= cell->vl_naddrs)
		return NULL;

	return &cell->vl_addrs[pos];
}

/*
 * move to next cell in cells list
 */
static void *afs_proc_cell_vlservers_next(struct seq_file *p, void *v,
					  loff_t *_pos)
{
	struct afs_cell *cell = p->private;
	loff_t pos;

	_enter("cell=%p{nad=%u} pos=%Ld", cell, cell->vl_naddrs, *_pos);

	pos = *_pos;
	(*_pos)++;
	if (pos >= cell->vl_naddrs)
		return NULL;

	return &cell->vl_addrs[pos];
}

/*
 * clean up after reading from the cells list
 */
static void afs_proc_cell_vlservers_stop(struct seq_file *p, void *v)
{
	struct afs_cell *cell = p->private;

	up_read(&cell->vl_sem);
}

/*
 * display a header line followed by a load of volume lines
 */
static int afs_proc_cell_vlservers_show(struct seq_file *m, void *v)
{
	struct in_addr *addr = v;

	/* display header on line 1 */
	if (v == (struct in_addr *) 1) {
		seq_puts(m, "ADDRESS\n");
		return 0;
	}

	/* display one cell per line on subsequent lines */
	seq_printf(m, "%u.%u.%u.%u\n", NIPQUAD(addr->s_addr));
	return 0;
}

/*
 * open "/proc/fs/afs/<cell>/servers" which provides a summary of active
 * servers
 */
static int afs_proc_cell_servers_open(struct inode *inode, struct file *file)
{
	struct afs_cell *cell;
	struct seq_file *m;
	int ret;

	cell = PDE(inode)->data;
	if (!cell)
		return -ENOENT;

	ret = seq_open(file, &afs_proc_cell_servers_ops);
	if (ret < 0)
		return ret;

	m = file->private_data;
	m->private = cell;
	return 0;
}

/*
 * close the file and release the ref to the cell
 */
static int afs_proc_cell_servers_release(struct inode *inode,
					 struct file *file)
{
	return seq_release(inode, file);
}

/*
 * set up the iterator to start reading from the cells list and return the
 * first item
 */
static void *afs_proc_cell_servers_start(struct seq_file *m, loff_t *_pos)
	__acquires(m->private->servers_lock)
{
	struct afs_cell *cell = m->private;

	_enter("cell=%p pos=%Ld", cell, *_pos);

	/* lock the list against modification */
	read_lock(&cell->servers_lock);
	return seq_list_start_head(&cell->servers, *_pos);
}

/*
 * move to next cell in cells list
 */
static void *afs_proc_cell_servers_next(struct seq_file *p, void *v,
					loff_t *_pos)
{
	struct afs_cell *cell = p->private;

	_enter("cell=%p pos=%Ld", cell, *_pos);
	return seq_list_next(v, &cell->servers, _pos);
}

/*
 * clean up after reading from the cells list
 */
static void afs_proc_cell_servers_stop(struct seq_file *p, void *v)
	__releases(p->private->servers_lock)
{
	struct afs_cell *cell = p->private;

	read_unlock(&cell->servers_lock);
}

/*
 * display a header line followed by a load of volume lines
 */
static int afs_proc_cell_servers_show(struct seq_file *m, void *v)
{
	struct afs_cell *cell = m->private;
	struct afs_server *server = list_entry(v, struct afs_server, link);
	char ipaddr[20];

	/* display header on line 1 */
	if (v == &cell->servers) {
		seq_puts(m, "USE ADDR            STATE\n");
		return 0;
	}

	/* display one cell per line on subsequent lines */
	sprintf(ipaddr, "%u.%u.%u.%u", NIPQUAD(server->addr));
	seq_printf(m, "%3d %-15.15s %5d\n",
		   atomic_read(&server->usage), ipaddr, server->fs_state);

	return 0;
}