/*

   *	Procfs interface for the PCI bus.
   *
   *	Copyright (c) 1997--1999 Martin Mares <mj@ucw.cz>
   */
  
  #include <linux/init.h>
  #include <linux/pci.h>

  #include <linux/slab.h>

  #include <linux/module.h>
  #include <linux/proc_fs.h>
  #include <linux/seq_file.h>

  #include <linux/capability.h>

  #include <asm/uaccess.h>
  #include <asm/byteorder.h>

  #include "pci.h"

  
  static int proc_initialized;	/* = 0 */
  
  static loff_t
  proc_bus_pci_lseek(struct file *file, loff_t off, int whence)
  {
  	loff_t new = -1;

  	struct inode *inode = file->f_path.dentry->d_inode;

  	mutex_lock(&inode->i_mutex);

  	switch (whence) {
  	case 0:
  		new = off;
  		break;
  	case 1:
  		new = file->f_pos + off;
  		break;
  	case 2:
  		new = inode->i_size + off;
  		break;
  	}
  	if (new < 0 || new > inode->i_size)
  		new = -EINVAL;
  	else
  		file->f_pos = new;

  	mutex_unlock(&inode->i_mutex);

  	return new;
  }
  
  static ssize_t
  proc_bus_pci_read(struct file *file, char __user *buf, size_t nbytes, loff_t *ppos)
  {

  	const struct inode *ino = file->f_path.dentry->d_inode;

  	const struct proc_dir_entry *dp = PDE(ino);
  	struct pci_dev *dev = dp->data;
  	unsigned int pos = *ppos;
  	unsigned int cnt, size;
  
  	/*
  	 * Normal users can read only the standardized portion of the
  	 * configuration space as several chips lock up when trying to read
  	 * undefined locations (think of Intel PIIX4 as a typical example).
  	 */
  
  	if (capable(CAP_SYS_ADMIN))

  		size = dp->size;

  	else if (dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)
  		size = 128;
  	else
  		size = 64;
  
  	if (pos >= size)
  		return 0;
  	if (nbytes >= size)
  		nbytes = size;
  	if (pos + nbytes > size)
  		nbytes = size - pos;
  	cnt = nbytes;
  
  	if (!access_ok(VERIFY_WRITE, buf, cnt))
  		return -EINVAL;
  
  	if ((pos & 1) && cnt) {
  		unsigned char val;

  		pci_user_read_config_byte(dev, pos, &val);

  		__put_user(val, buf);
  		buf++;
  		pos++;
  		cnt--;
  	}
  
  	if ((pos & 3) && cnt > 2) {
  		unsigned short val;

  		pci_user_read_config_word(dev, pos, &val);

  		__put_user(cpu_to_le16(val), (__le16 __user *) buf);

  		buf += 2;
  		pos += 2;
  		cnt -= 2;
  	}
  
  	while (cnt >= 4) {
  		unsigned int val;

  		pci_user_read_config_dword(dev, pos, &val);

  		__put_user(cpu_to_le32(val), (__le32 __user *) buf);

  		buf += 4;
  		pos += 4;
  		cnt -= 4;
  	}
  
  	if (cnt >= 2) {
  		unsigned short val;

  		pci_user_read_config_word(dev, pos, &val);

  		__put_user(cpu_to_le16(val), (__le16 __user *) buf);

  		buf += 2;
  		pos += 2;
  		cnt -= 2;
  	}
  
  	if (cnt) {
  		unsigned char val;

  		pci_user_read_config_byte(dev, pos, &val);

  		__put_user(val, buf);
  		buf++;
  		pos++;
  		cnt--;
  	}
  
  	*ppos = pos;
  	return nbytes;
  }
  
  static ssize_t
  proc_bus_pci_write(struct file *file, const char __user *buf, size_t nbytes, loff_t *ppos)
  {

  	struct inode *ino = file->f_path.dentry->d_inode;

  	const struct proc_dir_entry *dp = PDE(ino);
  	struct pci_dev *dev = dp->data;
  	int pos = *ppos;

  	int size = dp->size;

  	int cnt;
  
  	if (pos >= size)
  		return 0;
  	if (nbytes >= size)
  		nbytes = size;
  	if (pos + nbytes > size)
  		nbytes = size - pos;
  	cnt = nbytes;
  
  	if (!access_ok(VERIFY_READ, buf, cnt))
  		return -EINVAL;
  
  	if ((pos & 1) && cnt) {
  		unsigned char val;
  		__get_user(val, buf);

  		pci_user_write_config_byte(dev, pos, val);

  		buf++;
  		pos++;
  		cnt--;
  	}
  
  	if ((pos & 3) && cnt > 2) {

  		__le16 val;
  		__get_user(val, (__le16 __user *) buf);

  		pci_user_write_config_word(dev, pos, le16_to_cpu(val));

  		buf += 2;
  		pos += 2;
  		cnt -= 2;
  	}
  
  	while (cnt >= 4) {

  		__le32 val;
  		__get_user(val, (__le32 __user *) buf);

  		pci_user_write_config_dword(dev, pos, le32_to_cpu(val));

  		buf += 4;
  		pos += 4;
  		cnt -= 4;
  	}
  
  	if (cnt >= 2) {

  		__le16 val;
  		__get_user(val, (__le16 __user *) buf);

  		pci_user_write_config_word(dev, pos, le16_to_cpu(val));

  		buf += 2;
  		pos += 2;
  		cnt -= 2;
  	}
  
  	if (cnt) {
  		unsigned char val;
  		__get_user(val, buf);

  		pci_user_write_config_byte(dev, pos, val);

  		buf++;
  		pos++;
  		cnt--;
  	}
  
  	*ppos = pos;

  	i_size_write(ino, dp->size);

  	return nbytes;
  }
  
  struct pci_filp_private {
  	enum pci_mmap_state mmap_state;
  	int write_combine;
  };

  static long proc_bus_pci_ioctl(struct file *file, unsigned int cmd,
  			       unsigned long arg)

  {

  	const struct proc_dir_entry *dp = PDE(file->f_dentry->d_inode);

  	struct pci_dev *dev = dp->data;
  #ifdef HAVE_PCI_MMAP
  	struct pci_filp_private *fpriv = file->private_data;
  #endif /* HAVE_PCI_MMAP */
  	int ret = 0;
  
  	switch (cmd) {
  	case PCIIOC_CONTROLLER:
  		ret = pci_domain_nr(dev->bus);
  		break;
  
  #ifdef HAVE_PCI_MMAP
  	case PCIIOC_MMAP_IS_IO:
  		fpriv->mmap_state = pci_mmap_io;
  		break;
  
  	case PCIIOC_MMAP_IS_MEM:
  		fpriv->mmap_state = pci_mmap_mem;
  		break;
  
  	case PCIIOC_WRITE_COMBINE:
  		if (arg)
  			fpriv->write_combine = 1;
  		else
  			fpriv->write_combine = 0;
  		break;
  
  #endif /* HAVE_PCI_MMAP */
  
  	default:
  		ret = -EINVAL;
  		break;
  	};
  
  	return ret;
  }
  
  #ifdef HAVE_PCI_MMAP
  static int proc_bus_pci_mmap(struct file *file, struct vm_area_struct *vma)
  {

  	struct inode *inode = file->f_path.dentry->d_inode;

  	const struct proc_dir_entry *dp = PDE(inode);
  	struct pci_dev *dev = dp->data;
  	struct pci_filp_private *fpriv = file->private_data;

  	int i, ret;

  
  	if (!capable(CAP_SYS_RAWIO))
  		return -EPERM;

  	/* Make sure the caller is mapping a real resource for this device */
  	for (i = 0; i < PCI_ROM_RESOURCE; i++) {

  		if (pci_mmap_fits(dev, i, vma,  PCI_MMAP_PROCFS))

  			break;
  	}
  
  	if (i >= PCI_ROM_RESOURCE)
  		return -ENODEV;

  	ret = pci_mmap_page_range(dev, vma,
  				  fpriv->mmap_state,
  				  fpriv->write_combine);
  	if (ret < 0)
  		return ret;
  
  	return 0;
  }
  
  static int proc_bus_pci_open(struct inode *inode, struct file *file)
  {
  	struct pci_filp_private *fpriv = kmalloc(sizeof(*fpriv), GFP_KERNEL);
  
  	if (!fpriv)
  		return -ENOMEM;
  
  	fpriv->mmap_state = pci_mmap_io;
  	fpriv->write_combine = 0;
  
  	file->private_data = fpriv;
  
  	return 0;
  }
  
  static int proc_bus_pci_release(struct inode *inode, struct file *file)
  {
  	kfree(file->private_data);
  	file->private_data = NULL;
  
  	return 0;
  }
  #endif /* HAVE_PCI_MMAP */

  static const struct file_operations proc_bus_pci_operations = {

  	.owner		= THIS_MODULE,

  	.llseek		= proc_bus_pci_lseek,
  	.read		= proc_bus_pci_read,
  	.write		= proc_bus_pci_write,

  	.unlocked_ioctl	= proc_bus_pci_ioctl,

  	.compat_ioctl	= proc_bus_pci_ioctl,

  #ifdef HAVE_PCI_MMAP
  	.open		= proc_bus_pci_open,
  	.release	= proc_bus_pci_release,
  	.mmap		= proc_bus_pci_mmap,
  #ifdef HAVE_ARCH_PCI_GET_UNMAPPED_AREA
  	.get_unmapped_area = get_pci_unmapped_area,
  #endif /* HAVE_ARCH_PCI_GET_UNMAPPED_AREA */
  #endif /* HAVE_PCI_MMAP */
  };

  /* iterator */
  static void *pci_seq_start(struct seq_file *m, loff_t *pos)
  {
  	struct pci_dev *dev = NULL;
  	loff_t n = *pos;
  
  	for_each_pci_dev(dev) {
  		if (!n--)
  			break;
  	}
  	return dev;
  }
  
  static void *pci_seq_next(struct seq_file *m, void *v, loff_t *pos)
  {
  	struct pci_dev *dev = v;
  
  	(*pos)++;
  	dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev);
  	return dev;
  }
  
  static void pci_seq_stop(struct seq_file *m, void *v)
  {
  	if (v) {
  		struct pci_dev *dev = v;
  		pci_dev_put(dev);
  	}
  }
  
  static int show_device(struct seq_file *m, void *v)
  {
  	const struct pci_dev *dev = v;
  	const struct pci_driver *drv;
  	int i;
  
  	if (dev == NULL)
  		return 0;
  
  	drv = pci_dev_driver(dev);
  	seq_printf(m, "%02x%02x\t%04x%04x\t%x",
  			dev->bus->number,
  			dev->devfn,
  			dev->vendor,
  			dev->device,
  			dev->irq);

  
  	/* only print standard and ROM resources to preserve compatibility */
  	for (i = 0; i <= PCI_ROM_RESOURCE; i++) {

  		resource_size_t start, end;

  		pci_resource_to_user(dev, i, &dev->resource[i], &start, &end);

  		seq_printf(m, "\t%16llx",
  			(unsigned long long)(start |
  			(dev->resource[i].flags & PCI_REGION_FLAG_MASK)));

  	}

  	for (i = 0; i <= PCI_ROM_RESOURCE; i++) {

  		resource_size_t start, end;

  		pci_resource_to_user(dev, i, &dev->resource[i], &start, &end);

  		seq_printf(m, "\t%16llx",

  			dev->resource[i].start < dev->resource[i].end ?

  			(unsigned long long)(end - start) + 1 : 0);

  	}

  	seq_putc(m, '\t');
  	if (drv)
  		seq_printf(m, "%s", drv->name);
  	seq_putc(m, '
  ');
  	return 0;
  }

  static const struct seq_operations proc_bus_pci_devices_op = {

  	.start	= pci_seq_start,
  	.next	= pci_seq_next,
  	.stop	= pci_seq_stop,
  	.show	= show_device
  };
  
  static struct proc_dir_entry *proc_bus_pci_dir;
  
  int pci_proc_attach_device(struct pci_dev *dev)
  {
  	struct pci_bus *bus = dev->bus;
  	struct proc_dir_entry *e;
  	char name[16];
  
  	if (!proc_initialized)
  		return -EACCES;
  
  	if (!bus->procdir) {
  		if (pci_proc_domain(bus)) {
  			sprintf(name, "%04x:%02x", pci_domain_nr(bus),
  					bus->number);
  		} else {
  			sprintf(name, "%02x", bus->number);
  		}
  		bus->procdir = proc_mkdir(name, proc_bus_pci_dir);
  		if (!bus->procdir)
  			return -ENOMEM;
  	}
  
  	sprintf(name, "%02x.%x", PCI_SLOT(dev->devfn), PCI_FUNC(dev->devfn));

  	e = proc_create_data(name, S_IFREG | S_IRUGO | S_IWUSR, bus->procdir,
  			     &proc_bus_pci_operations, dev);

  	if (!e)
  		return -ENOMEM;

  	e->size = dev->cfg_size;
  	dev->procent = e;
  
  	return 0;
  }
  
  int pci_proc_detach_device(struct pci_dev *dev)
  {
  	struct proc_dir_entry *e;
  
  	if ((e = dev->procent)) {

  		remove_proc_entry(e->name, dev->bus->procdir);
  		dev->procent = NULL;
  	}
  	return 0;
  }

  #if 0

  int pci_proc_attach_bus(struct pci_bus* bus)
  {
  	struct proc_dir_entry *de = bus->procdir;
  
  	if (!proc_initialized)
  		return -EACCES;
  
  	if (!de) {
  		char name[16];
  		sprintf(name, "%02x", bus->number);
  		de = bus->procdir = proc_mkdir(name, proc_bus_pci_dir);
  		if (!de)
  			return -ENOMEM;
  	}
  	return 0;
  }

  #endif  /*  0  */

  
  int pci_proc_detach_bus(struct pci_bus* bus)
  {
  	struct proc_dir_entry *de = bus->procdir;
  	if (de)
  		remove_proc_entry(de->name, proc_bus_pci_dir);
  	return 0;
  }

  static int proc_bus_pci_dev_open(struct inode *inode, struct file *file)
  {
  	return seq_open(file, &proc_bus_pci_devices_op);
  }

  static const struct file_operations proc_bus_pci_dev_operations = {

  	.owner		= THIS_MODULE,

  	.open		= proc_bus_pci_dev_open,
  	.read		= seq_read,
  	.llseek		= seq_lseek,
  	.release	= seq_release,
  };
  
  static int __init pci_proc_init(void)
  {

  	struct pci_dev *dev = NULL;

  	proc_bus_pci_dir = proc_mkdir("bus/pci", NULL);

  	proc_create("devices", 0, proc_bus_pci_dir,
  		    &proc_bus_pci_dev_operations);

  	proc_initialized = 1;

  	for_each_pci_dev(dev)

  		pci_proc_attach_device(dev);

  	return 0;
  }

  device_initcall(pci_proc_init);