text: /*
   * drivers/pci/pci-sysfs.c
   *
   * (C) Copyright 2002-2004 Greg Kroah-Hartman <greg@kroah.com>
   * (C) Copyright 2002-2004 IBM Corp.
   * (C) Copyright 2003 Matthew Wilcox
   * (C) Copyright 2003 Hewlett-Packard
   * (C) Copyright 2004 Jon Smirl <jonsmirl@yahoo.com>
   * (C) Copyright 2004 Silicon Graphics, Inc. Jesse Barnes <jbarnes@sgi.com>
   *
   * File attributes for PCI devices
   *
   * Modeled after usb's driverfs.c 
   *
   */
  
  
  #include <linux/kernel.h>
  #include <linux/pci.h>
  #include <linux/stat.h>
  #include <linux/topology.h>
  #include <linux/mm.h>
  
  #include "pci.h"
  
  static int sysfs_initialized;	/* = 0 */
  
  /* show configuration fields */
  #define pci_config_attr(field, format_string)				\
  static ssize_t								\
  field##_show(struct device *dev, struct device_attribute *attr, char *buf)				\
  {									\
  	struct pci_dev *pdev;						\
  									\
  	pdev = to_pci_dev (dev);					\
  	return sprintf (buf, format_string, pdev->field);		\
  }
  
  pci_config_attr(vendor, "0x%04x\n");
  pci_config_attr(device, "0x%04x\n");
  pci_config_attr(subsystem_vendor, "0x%04x\n");
  pci_config_attr(subsystem_device, "0x%04x\n");
  pci_config_attr(class, "0x%06x\n");
  pci_config_attr(irq, "%u\n");
  
  static ssize_t broken_parity_status_show(struct device *dev,
  					 struct device_attribute *attr,
  					 char *buf)
  {
  	struct pci_dev *pdev = to_pci_dev(dev);
  	return sprintf (buf, "%u\n", pdev->broken_parity_status);
  }
  
  static ssize_t broken_parity_status_store(struct device *dev,
  					  struct device_attribute *attr,
  					  const char *buf, size_t count)
  {
  	struct pci_dev *pdev = to_pci_dev(dev);
  	ssize_t consumed = -EINVAL;
  
  	if ((count > 0) && (*buf == '0' || *buf == '1')) {
  		pdev->broken_parity_status = *buf == '1' ? 1 : 0;
  		consumed = count;
  	}
  	return consumed;
  }
  
  static ssize_t local_cpus_show(struct device *dev,
  			struct device_attribute *attr, char *buf)
  {		
  	cpumask_t mask;
  	int len;
  
  	mask = pcibus_to_cpumask(to_pci_dev(dev)->bus);
  	len = cpumask_scnprintf(buf, PAGE_SIZE-2, mask);
  	strcat(buf,"\n"); 
  	return 1+len;
  }
  
  /* show resources */
  static ssize_t
  resource_show(struct device * dev, struct device_attribute *attr, char * buf)
  {
  	struct pci_dev * pci_dev = to_pci_dev(dev);
  	char * str = buf;
  	int i;
  	int max = 7;
  	resource_size_t start, end;
  
  	if (pci_dev->subordinate)
  		max = DEVICE_COUNT_RESOURCE;
  
  	for (i = 0; i < max; i++) {
  		struct resource *res =  &pci_dev->resource[i];
  		pci_resource_to_user(pci_dev, i, res, &start, &end);
  		str += sprintf(str,"0x%016llx 0x%016llx 0x%016llx\n",
  			       (unsigned long long)start,
  			       (unsigned long long)end,
  			       (unsigned long long)res->flags);
  	}
  	return (str - buf);
  }
  
  static ssize_t modalias_show(struct device *dev, struct device_attribute *attr, char *buf)
  {
  	struct pci_dev *pci_dev = to_pci_dev(dev);
  
  	return sprintf(buf, "pci:v%08Xd%08Xsv%08Xsd%08Xbc%02Xsc%02Xi%02x\n",
  		       pci_dev->vendor, pci_dev->device,
  		       pci_dev->subsystem_vendor, pci_dev->subsystem_device,
  		       (u8)(pci_dev->class >> 16), (u8)(pci_dev->class >> 8),
  		       (u8)(pci_dev->class));
  }
  
  static ssize_t is_enabled_store(struct device *dev,
  				struct device_attribute *attr, const char *buf,
  				size_t count)
  {
  	ssize_t result = -EINVAL;
  	struct pci_dev *pdev = to_pci_dev(dev);
  
  	/* this can crash the machine when done on the "wrong" device */
  	if (!capable(CAP_SYS_ADMIN))
  		return count;
  
  	if (*buf == '0') {
  		if (atomic_read(&pdev->enable_cnt) != 0)
  			pci_disable_device(pdev);
  		else
  			result = -EIO;
  	} else if (*buf == '1')
  		result = pci_enable_device(pdev);
  
  	return result < 0 ? result : count;
  }
  
  static ssize_t is_enabled_show(struct device *dev,
  			       struct device_attribute *attr, char *buf)
  {
  	struct pci_dev *pdev;
  
  	pdev = to_pci_dev (dev);
  	return sprintf (buf, "%u\n", atomic_read(&pdev->enable_cnt));
  }
  
  #ifdef CONFIG_NUMA
  static ssize_t
  numa_node_show(struct device *dev, struct device_attribute *attr, char *buf)
  {
  	return sprintf (buf, "%d\n", dev->numa_node);
  }
  #endif
  
  static ssize_t
  msi_bus_show(struct device *dev, struct device_attribute *attr, char *buf)
  {
  	struct pci_dev *pdev = to_pci_dev(dev);
  
  	if (!pdev->subordinate)
  		return 0;
  
  	return sprintf (buf, "%u\n",
  			!(pdev->subordinate->bus_flags & PCI_BUS_FLAGS_NO_MSI));
  }
  
  static ssize_t
  msi_bus_store(struct device *dev, struct device_attribute *attr,
  	      const char *buf, size_t count)
  {
  	struct pci_dev *pdev = to_pci_dev(dev);
  
  	/* bad things may happen if the no_msi flag is changed
  	 * while some drivers are loaded */
  	if (!capable(CAP_SYS_ADMIN))
  		return count;
  
  	if (!pdev->subordinate)
  		return count;
  
  	if (*buf == '0') {
  		pdev->subordinate->bus_flags |= PCI_BUS_FLAGS_NO_MSI;
  		dev_warn(&pdev->dev, "forced subordinate bus to not support MSI,"
  			 " bad things could happen.\n");
  	}
  
  	if (*buf == '1') {
  		pdev->subordinate->bus_flags &= ~PCI_BUS_FLAGS_NO_MSI;
  		dev_warn(&pdev->dev, "forced subordinate bus to support MSI,"
  			 " bad things could happen.\n");
  	}
  
  	return count;
  }
  
  struct device_attribute pci_dev_attrs[] = {
  	__ATTR_RO(resource),
  	__ATTR_RO(vendor),
  	__ATTR_RO(device),
  	__ATTR_RO(subsystem_vendor),
  	__ATTR_RO(subsystem_device),
  	__ATTR_RO(class),
  	__ATTR_RO(irq),
  	__ATTR_RO(local_cpus),
  	__ATTR_RO(modalias),
  #ifdef CONFIG_NUMA
  	__ATTR_RO(numa_node),
  #endif
  	__ATTR(enable, 0600, is_enabled_show, is_enabled_store),
  	__ATTR(broken_parity_status,(S_IRUGO|S_IWUSR),
  		broken_parity_status_show,broken_parity_status_store),
  	__ATTR(msi_bus, 0644, msi_bus_show, msi_bus_store),
  	__ATTR_NULL,
  };
  
  static ssize_t
  pci_read_config(struct kobject *kobj, char *buf, loff_t off, size_t count)
  {
  	struct pci_dev *dev = to_pci_dev(container_of(kobj,struct device,kobj));
  	unsigned int size = 64;
  	loff_t init_off = off;
  	u8 *data = (u8*) buf;
  
  	/* Several chips lock up trying to read undefined config space */
  	if (capable(CAP_SYS_ADMIN)) {
  		size = dev->cfg_size;
  	} else if (dev->hdr_type == PCI_HEADER_TYPE_CARDBUS) {
  		size = 128;
  	}
  
  	if (off > size)
  		return 0;
  	if (off + count > size) {
  		size -= off;
  		count = size;
  	} else {
  		size = count;
  	}
  
  	if ((off & 1) && size) {
  		u8 val;
  		pci_user_read_config_byte(dev, off, &val);
  		data[off - init_off] = val;
  		off++;
  		size--;
  	}
  
  	if ((off & 3) && size > 2) {
  		u16 val;
  		pci_user_read_config_word(dev, off, &val);
  		data[off - init_off] = val & 0xff;
  		data[off - init_off + 1] = (val >> 8) & 0xff;
  		off += 2;
  		size -= 2;
  	}
  
  	while (size > 3) {
  		u32 val;
  		pci_user_read_config_dword(dev, off, &val);
  		data[off - init_off] = val & 0xff;
  		data[off - init_off + 1] = (val >> 8) & 0xff;
  		data[off - init_off + 2] = (val >> 16) & 0xff;
  		data[off - init_off + 3] = (val >> 24) & 0xff;
  		off += 4;
  		size -= 4;
  	}
  
  	if (size >= 2) {
  		u16 val;
  		pci_user_read_config_word(dev, off, &val);
  		data[off - init_off] = val & 0xff;
  		data[off - init_off + 1] = (val >> 8) & 0xff;
  		off += 2;
  		size -= 2;
  	}
  
  	if (size > 0) {
  		u8 val;
  		pci_user_read_config_byte(dev, off, &val);
  		data[off - init_off] = val;
  		off++;
  		--size;
  	}
  
  	return count;
  }
  
  static ssize_t
  pci_write_config(struct kobject *kobj, char *buf, loff_t off, size_t count)
  {
  	struct pci_dev *dev = to_pci_dev(container_of(kobj,struct device,kobj));
  	unsigned int size = count;
  	loff_t init_off = off;
  	u8 *data = (u8*) buf;
  
  	if (off > dev->cfg_size)
  		return 0;
  	if (off + count > dev->cfg_size) {
  		size = dev->cfg_size - off;
  		count = size;
  	}
  	
  	if ((off & 1) && size) {
  		pci_user_write_config_byte(dev, off, data[off - init_off]);
  		off++;
  		size--;
  	}
  	
  	if ((off & 3) && size > 2) {
  		u16 val = data[off - init_off];
  		val |= (u16) data[off - init_off + 1] << 8;
                  pci_user_write_config_word(dev, off, val);
                  off += 2;
                  size -= 2;
          }
  
  	while (size > 3) {
  		u32 val = data[off - init_off];
  		val |= (u32) data[off - init_off + 1] << 8;
  		val |= (u32) data[off - init_off + 2] << 16;
  		val |= (u32) data[off - init_off + 3] << 24;
  		pci_user_write_config_dword(dev, off, val);
  		off += 4;
  		size -= 4;
  	}
  	
  	if (size >= 2) {
  		u16 val = data[off - init_off];
  		val |= (u16) data[off - init_off + 1] << 8;
  		pci_user_write_config_word(dev, off, val);
  		off += 2;
  		size -= 2;
  	}
  
  	if (size) {
  		pci_user_write_config_byte(dev, off, data[off - init_off]);
  		off++;
  		--size;
  	}
  
  	return count;
  }
  
  #ifdef HAVE_PCI_LEGACY
  /**
   * pci_read_legacy_io - read byte(s) from legacy I/O port space
   * @kobj: kobject corresponding to file to read from
   * @buf: buffer to store results
   * @off: offset into legacy I/O port space
   * @count: number of bytes to read
   *
   * Reads 1, 2, or 4 bytes from legacy I/O port space using an arch specific
   * callback routine (pci_legacy_read).
   */
  ssize_t
  pci_read_legacy_io(struct kobject *kobj, char *buf, loff_t off, size_t count)
  {
          struct pci_bus *bus = to_pci_bus(container_of(kobj,
                                                        struct class_device,
  						      kobj));
  
          /* Only support 1, 2 or 4 byte accesses */
          if (count != 1 && count != 2 && count != 4)
                  return -EINVAL;
  
          return pci_legacy_read(bus, off, (u32 *)buf, count);
  }
  
  /**
   * pci_write_legacy_io - write byte(s) to legacy I/O port space
   * @kobj: kobject corresponding to file to read from
   * @buf: buffer containing value to be written
   * @off: offset into legacy I/O port space
   * @count: number of bytes to write
   *
   * Writes 1, 2, or 4 bytes from legacy I/O port space using an arch specific
   * callback routine (pci_legacy_write).
   */
  ssize_t
  pci_write_legacy_io(struct kobject *kobj, char *buf, loff_t off, size_t count)
  {
          struct pci_bus *bus = to_pci_bus(container_of(kobj,
  						      struct class_device,
  						      kobj));
          /* Only support 1, 2 or 4 byte accesses */
          if (count != 1 && count != 2 && count != 4)
                  return -EINVAL;
  
          return pci_legacy_write(bus, off, *(u32 *)buf, count);
  }
  
  /**
   * pci_mmap_legacy_mem - map legacy PCI memory into user memory space
   * @kobj: kobject corresponding to device to be mapped
   * @attr: struct bin_attribute for this file
   * @vma: struct vm_area_struct passed to mmap
   *
   * Uses an arch specific callback, pci_mmap_legacy_page_range, to mmap
   * legacy memory space (first meg of bus space) into application virtual
   * memory space.
   */
  int
  pci_mmap_legacy_mem(struct kobject *kobj, struct bin_attribute *attr,
                      struct vm_area_struct *vma)
  {
          struct pci_bus *bus = to_pci_bus(container_of(kobj,
                                                        struct class_device,
  						      kobj));
  
          return pci_mmap_legacy_page_range(bus, vma);
  }
  #endif /* HAVE_PCI_LEGACY */
  
  #ifdef HAVE_PCI_MMAP
  /**
   * pci_mmap_resource - map a PCI resource into user memory space
   * @kobj: kobject for mapping
   * @attr: struct bin_attribute for the file being mapped
   * @vma: struct vm_area_struct passed into the mmap
   *
   * Use the regular PCI mapping routines to map a PCI resource into userspace.
   * FIXME: write combining?  maybe automatic for prefetchable regions?
   */
  static int
  pci_mmap_resource(struct kobject *kobj, struct bin_attribute *attr,
  		  struct vm_area_struct *vma)
  {
  	struct pci_dev *pdev = to_pci_dev(container_of(kobj,
  						       struct device, kobj));
  	struct resource *res = (struct resource *)attr->private;
  	enum pci_mmap_state mmap_type;
  	resource_size_t start, end;
  	int i;
  
  	for (i = 0; i < PCI_ROM_RESOURCE; i++)
  		if (res == &pdev->resource[i])
  			break;
  	if (i >= PCI_ROM_RESOURCE)
  		return -ENODEV;
  
  	/* pci_mmap_page_range() expects the same kind of entry as coming
  	 * from /proc/bus/pci/ which is a "user visible" value. If this is
  	 * different from the resource itself, arch will do necessary fixup.
  	 */
  	pci_resource_to_user(pdev, i, res, &start, &end);
  	vma->vm_pgoff += start >> PAGE_SHIFT;
  	mmap_type = res->flags & IORESOURCE_MEM ? pci_mmap_mem : pci_mmap_io;
  
  	return pci_mmap_page_range(pdev, vma, mmap_type, 0);
  }
  
  /**
   * pci_remove_resource_files - cleanup resource files
   * @dev: dev to cleanup
   *
   * If we created resource files for @dev, remove them from sysfs and
   * free their resources.
   */
  static void
  pci_remove_resource_files(struct pci_dev *pdev)
  {
  	int i;
  
  	for (i = 0; i < PCI_ROM_RESOURCE; i++) {
  		struct bin_attribute *res_attr;
  
  		res_attr = pdev->res_attr[i];
  		if (res_attr) {
  			sysfs_remove_bin_file(&pdev->dev.kobj, res_attr);
  			kfree(res_attr);
  		}
  	}
  }
  
  /**
   * pci_create_resource_files - create resource files in sysfs for @dev
   * @dev: dev in question
   *
   * Walk the resources in @dev creating files for each resource available.
   */
  static int pci_create_resource_files(struct pci_dev *pdev)
  {
  	int i;
  	int retval;
  
  	/* Expose the PCI resources from this device as files */
  	for (i = 0; i < PCI_ROM_RESOURCE; i++) {
  		struct bin_attribute *res_attr;
  
  		/* skip empty resources */
  		if (!pci_resource_len(pdev, i))
  			continue;
  
  		/* allocate attribute structure, piggyback attribute name */
  		res_attr = kzalloc(sizeof(*res_attr) + 10, GFP_ATOMIC);
  		if (res_attr) {
  			char *res_attr_name = (char *)(res_attr + 1);
  
  			pdev->res_attr[i] = res_attr;
  			sprintf(res_attr_name, "resource%d", i);
  			res_attr->attr.name = res_attr_name;
  			res_attr->attr.mode = S_IRUSR | S_IWUSR;
  			res_attr->attr.owner = THIS_MODULE;
  			res_attr->size = pci_resource_len(pdev, i);
  			res_attr->mmap = pci_mmap_resource;
  			res_attr->private = &pdev->resource[i];
  			retval = sysfs_create_bin_file(&pdev->dev.kobj, res_attr);
  			if (retval) {
  				pci_remove_resource_files(pdev);
  				return retval;
  			}
  		} else {
  			return -ENOMEM;
  		}
  	}
  	return 0;
  }
  #else /* !HAVE_PCI_MMAP */
  static inline int pci_create_resource_files(struct pci_dev *dev) { return 0; }
  static inline void pci_remove_resource_files(struct pci_dev *dev) { return; }
  #endif /* HAVE_PCI_MMAP */
  
  /**
   * pci_write_rom - used to enable access to the PCI ROM display
   * @kobj: kernel object handle
   * @buf: user input
   * @off: file offset
   * @count: number of byte in input
   *
   * writing anything except 0 enables it
   */
  static ssize_t
  pci_write_rom(struct kobject *kobj, char *buf, loff_t off, size_t count)
  {
  	struct pci_dev *pdev = to_pci_dev(container_of(kobj, struct device, kobj));
  
  	if ((off ==  0) && (*buf == '0') && (count == 2))
  		pdev->rom_attr_enabled = 0;
  	else
  		pdev->rom_attr_enabled = 1;
  
  	return count;
  }
  
  /**
   * pci_read_rom - read a PCI ROM
   * @kobj: kernel object handle
   * @buf: where to put the data we read from the ROM
   * @off: file offset
   * @count: number of bytes to read
   *
   * Put @count bytes starting at @off into @buf from the ROM in the PCI
   * device corresponding to @kobj.
   */
  static ssize_t
  pci_read_rom(struct kobject *kobj, char *buf, loff_t off, size_t count)
  {
  	struct pci_dev *pdev = to_pci_dev(container_of(kobj, struct device, kobj));
  	void __iomem *rom;
  	size_t size;
  
  	if (!pdev->rom_attr_enabled)
  		return -EINVAL;
  	
  	rom = pci_map_rom(pdev, &size);	/* size starts out as PCI window size */
  	if (!rom)
  		return 0;
  		
  	if (off >= size)
  		count = 0;
  	else {
  		if (off + count > size)
  			count = size - off;
  		
  		memcpy_fromio(buf, rom + off, count);
  	}
  	pci_unmap_rom(pdev, rom);
  		
  	return count;
  }
  
  static struct bin_attribute pci_config_attr = {
  	.attr =	{
  		.name = "config",
  		.mode = S_IRUGO | S_IWUSR,
  		.owner = THIS_MODULE,
  	},
  	.size = 256,
  	.read = pci_read_config,
  	.write = pci_write_config,
  };
  
  static struct bin_attribute pcie_config_attr = {
  	.attr =	{
  		.name = "config",
  		.mode = S_IRUGO | S_IWUSR,
  		.owner = THIS_MODULE,
  	},
  	.size = 4096,
  	.read = pci_read_config,
  	.write = pci_write_config,
  };
  
  int __must_check pci_create_sysfs_dev_files (struct pci_dev *pdev)
  {
  	struct bin_attribute *rom_attr = NULL;
  	int retval;
  
  	if (!sysfs_initialized)
  		return -EACCES;
  
  	if (pdev->cfg_size < 4096)
  		retval = sysfs_create_bin_file(&pdev->dev.kobj, &pci_config_attr);
  	else
  		retval = sysfs_create_bin_file(&pdev->dev.kobj, &pcie_config_attr);
  	if (retval)
  		goto err;
  
  	retval = pci_create_resource_files(pdev);
  	if (retval)
  		goto err_bin_file;
  
  	/* If the device has a ROM, try to expose it in sysfs. */
  	if (pci_resource_len(pdev, PCI_ROM_RESOURCE)) {
  		rom_attr = kzalloc(sizeof(*rom_attr), GFP_ATOMIC);
  		if (rom_attr) {
  			pdev->rom_attr = rom_attr;
  			rom_attr->size = pci_resource_len(pdev, PCI_ROM_RESOURCE);
  			rom_attr->attr.name = "rom";
  			rom_attr->attr.mode = S_IRUSR;
  			rom_attr->attr.owner = THIS_MODULE;
  			rom_attr->read = pci_read_rom;
  			rom_attr->write = pci_write_rom;
  			retval = sysfs_create_bin_file(&pdev->dev.kobj, rom_attr);
  			if (retval)
  				goto err_rom;
  		} else {
  			retval = -ENOMEM;
  			goto err_bin_file;
  		}
  	}
  	/* add platform-specific attributes */
  	pcibios_add_platform_entries(pdev);
  
  	return 0;
  
  err_rom:
  	kfree(rom_attr);
  err_bin_file:
  	if (pdev->cfg_size < 4096)
  		sysfs_remove_bin_file(&pdev->dev.kobj, &pci_config_attr);
  	else
  		sysfs_remove_bin_file(&pdev->dev.kobj, &pcie_config_attr);
  err:
  	return retval;
  }
  
  /**
   * pci_remove_sysfs_dev_files - cleanup PCI specific sysfs files
   * @pdev: device whose entries we should free
   *
   * Cleanup when @pdev is removed from sysfs.
   */
  void pci_remove_sysfs_dev_files(struct pci_dev *pdev)
  {
  	if (!sysfs_initialized)
  		return;
  
  	if (pdev->cfg_size < 4096)
  		sysfs_remove_bin_file(&pdev->dev.kobj, &pci_config_attr);
  	else
  		sysfs_remove_bin_file(&pdev->dev.kobj, &pcie_config_attr);
  
  	pci_remove_resource_files(pdev);
  
  	if (pci_resource_len(pdev, PCI_ROM_RESOURCE)) {
  		if (pdev->rom_attr) {
  			sysfs_remove_bin_file(&pdev->dev.kobj, pdev->rom_attr);
  			kfree(pdev->rom_attr);
  		}
  	}
  }
  
  static int __init pci_sysfs_init(void)
  {
  	struct pci_dev *pdev = NULL;
  	int retval;
  
  	sysfs_initialized = 1;
  	for_each_pci_dev(pdev) {
  		retval = pci_create_sysfs_dev_files(pdev);
  		if (retval)
  			return retval;
  	}
  
  	return 0;
  }
  
  __initcall(pci_sysfs_init);
  