1 files changed, 472 insertions, 0 deletions
diff --git a/drivers/pci/proc.c b/drivers/pci/proc.c
new file mode 100644
index 0000000000..f967709082
--- /dev/null
+++ b/drivers/pci/proc.c
@@ -0,0 +1,472 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * 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 <linux/uaccess.h>
+#include <linux/security.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)
+{
+	struct pci_dev *dev = pde_data(file_inode(file));
+	return fixed_size_llseek(file, off, whence, dev->cfg_size);
+}
+
+static ssize_t proc_bus_pci_read(struct file *file, char __user *buf,
+				 size_t nbytes, loff_t *ppos)
+{
+	struct pci_dev *dev = pde_data(file_inode(file));
+	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 = dev->cfg_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(buf, cnt))
+		return -EINVAL;
+
+	pci_config_pm_runtime_get(dev);
+
+	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;
+		cond_resched();
+	}
+
+	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);
+		pos++;
+	}
+
+	pci_config_pm_runtime_put(dev);
+
+	*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_inode(file);
+	struct pci_dev *dev = pde_data(ino);
+	int pos = *ppos;
+	int size = dev->cfg_size;
+	int cnt, ret;
+
+	ret = security_locked_down(LOCKDOWN_PCI_ACCESS);
+	if (ret)
+		return ret;
+
+	if (pos >= size)
+		return 0;
+	if (nbytes >= size)
+		nbytes = size;
+	if (pos + nbytes > size)
+		nbytes = size - pos;
+	cnt = nbytes;
+
+	if (!access_ok(buf, cnt))
+		return -EINVAL;
+
+	pci_config_pm_runtime_get(dev);
+
+	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);
+		pos++;
+	}
+
+	pci_config_pm_runtime_put(dev);
+
+	*ppos = pos;
+	i_size_write(ino, dev->cfg_size);
+	return nbytes;
+}
+
+#ifdef HAVE_PCI_MMAP
+struct pci_filp_private {
+	enum pci_mmap_state mmap_state;
+	int write_combine;
+};
+#endif /* HAVE_PCI_MMAP */
+
+static long proc_bus_pci_ioctl(struct file *file, unsigned int cmd,
+			       unsigned long arg)
+{
+	struct pci_dev *dev = pde_data(file_inode(file));
+#ifdef HAVE_PCI_MMAP
+	struct pci_filp_private *fpriv = file->private_data;
+#endif /* HAVE_PCI_MMAP */
+	int ret = 0;
+
+	ret = security_locked_down(LOCKDOWN_PCI_ACCESS);
+	if (ret)
+		return ret;
+
+	switch (cmd) {
+	case PCIIOC_CONTROLLER:
+		ret = pci_domain_nr(dev->bus);
+		break;
+
+#ifdef HAVE_PCI_MMAP
+	case PCIIOC_MMAP_IS_IO:
+		if (!arch_can_pci_mmap_io())
+			return -EINVAL;
+		fpriv->mmap_state = pci_mmap_io;
+		break;
+
+	case PCIIOC_MMAP_IS_MEM:
+		fpriv->mmap_state = pci_mmap_mem;
+		break;
+
+	case PCIIOC_WRITE_COMBINE:
+		if (arch_can_pci_mmap_wc()) {
+			if (arg)
+				fpriv->write_combine = 1;
+			else
+				fpriv->write_combine = 0;
+			break;
+		}
+		/* If arch decided it can't, fall through... */
+		fallthrough;
+#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 pci_dev *dev = pde_data(file_inode(file));
+	struct pci_filp_private *fpriv = file->private_data;
+	resource_size_t start, end;
+	int i, ret, write_combine = 0, res_bit = IORESOURCE_MEM;
+
+	if (!capable(CAP_SYS_RAWIO) ||
+	    security_locked_down(LOCKDOWN_PCI_ACCESS))
+		return -EPERM;
+
+	if (fpriv->mmap_state == pci_mmap_io) {
+		if (!arch_can_pci_mmap_io())
+			return -EINVAL;
+		res_bit = IORESOURCE_IO;
+	}
+
+	/* Make sure the caller is mapping a real resource for this device */
+	for (i = 0; i < PCI_STD_NUM_BARS; i++) {
+		if (dev->resource[i].flags & res_bit &&
+		    pci_mmap_fits(dev, i, vma,  PCI_MMAP_PROCFS))
+			break;
+	}
+
+	if (i >= PCI_STD_NUM_BARS)
+		return -ENODEV;
+
+	if (fpriv->mmap_state == pci_mmap_mem &&
+	    fpriv->write_combine) {
+		if (dev->resource[i].flags & IORESOURCE_PREFETCH)
+			write_combine = 1;
+		else
+			return -EINVAL;
+	}
+
+	if (dev->resource[i].flags & IORESOURCE_MEM &&
+	    iomem_is_exclusive(dev->resource[i].start))
+		return -EINVAL;
+
+	pci_resource_to_user(dev, i, &dev->resource[i], &start, &end);
+
+	/* Adjust vm_pgoff to be the offset within the resource */
+	vma->vm_pgoff -= start >> PAGE_SHIFT;
+	ret = pci_mmap_resource_range(dev, i, vma,
+				  fpriv->mmap_state, 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;
+	file->f_mapping = iomem_get_mapping();
+
+	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 proc_ops proc_bus_pci_ops = {
+	.proc_lseek	= proc_bus_pci_lseek,
+	.proc_read	= proc_bus_pci_read,
+	.proc_write	= proc_bus_pci_write,
+	.proc_ioctl	= proc_bus_pci_ioctl,
+#ifdef CONFIG_COMPAT
+	.proc_compat_ioctl = proc_bus_pci_ioctl,
+#endif
+#ifdef HAVE_PCI_MMAP
+	.proc_open	= proc_bus_pci_open,
+	.proc_release	= proc_bus_pci_release,
+	.proc_mmap	= proc_bus_pci_mmap,
+#ifdef HAVE_ARCH_PCI_GET_UNMAPPED_AREA
+	.proc_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_puts(m, drv->name);
+	seq_putc(m, '\n');
+	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_ops, dev);
+	if (!e)
+		return -ENOMEM;
+	proc_set_size(e, dev->cfg_size);
+	dev->procent = e;
+
+	return 0;
+}
+
+int pci_proc_detach_device(struct pci_dev *dev)
+{
+	proc_remove(dev->procent);
+	dev->procent = NULL;
+	return 0;
+}
+
+int pci_proc_detach_bus(struct pci_bus *bus)
+{
+	proc_remove(bus->procdir);
+	return 0;
+}
+
+static int __init pci_proc_init(void)
+{
+	struct pci_dev *dev = NULL;
+	proc_bus_pci_dir = proc_mkdir("bus/pci", NULL);
+	proc_create_seq("devices", 0, proc_bus_pci_dir,
+		    &proc_bus_pci_devices_op);
+	proc_initialized = 1;
+	for_each_pci_dev(dev)
+		pci_proc_attach_device(dev);
+
+	return 0;
+}
+device_initcall(pci_proc_init);