sysfs: add parameter "struct bin_attribute *" in .read/.write methods for sysfs binary attributes

Well, first of all, I don't want to change so many files either.

What I do:
Adding a new parameter "struct bin_attribute *" in the
.read/.write methods for the sysfs binary attributes.

In fact, only the four lines change in fs/sysfs/bin.c and
include/linux/sysfs.h do the real work.
But I have to update all the files that use binary attributes
to make them compatible with the new .read and .write methods.
I'm not sure if I missed any. :(

Why I do this:
For a sysfs attribute, we can get a pointer pointing to the
struct attribute in the .show/.store method,
while we can't do this for the binary attributes.
I don't know why this is different, but this does make it not
so handy to use the binary attributes as the regular ones.
So I think this patch is reasonable. :)

Who benefits from it:
The patch that exposes ACPI tables in sysfs
requires such an improvement.
All the table binary attributes share the same .read method.
Parameter "struct bin_attribute *" is used to get
the table signature and instance number which are used to
distinguish different ACPI table binary attributes.

Without this parameter, we need to offer different .read methods
for different ACPI table binary attributes.
This is impossible as there are various ACPI tables on different
platforms, and we don't know what they are until they are loaded.

Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

2 files changed, 16 insertions, 8 deletions

diff --git a/drivers/pci/hotplug/acpiphp_ibm.c b/drivers/pci/hotplug/acpiphp_ibm.c
index 74556ec31a5..70db38c0ced 100644
--- a/drivers/pci/hotplug/acpiphp_ibm.c
+++ b/drivers/pci/hotplug/acpiphp_ibm.c
@@ -106,7 +106,8 @@ static int ibm_get_attention_status(struct hotplug_slot *slot, u8 *status);
 static void ibm_handle_events(acpi_handle handle, u32 event, void *context);
 static int ibm_get_table_from_acpi(char **bufp);
 static ssize_t ibm_read_apci_table(struct kobject *kobj,
-		char *buffer, loff_t pos, size_t size);
+				   struct bin_attribute *bin_attr,
+				   char *buffer, loff_t pos, size_t size);
 static acpi_status __init ibm_find_acpi_device(acpi_handle handle,
 		u32 lvl, void *context, void **rv);
 static int __init ibm_acpiphp_init(void);
@@ -357,7 +358,8 @@ read_table_done:
  * our solution is to only allow reading the table in all at once
  **/
 static ssize_t ibm_read_apci_table(struct kobject *kobj,
-		char *buffer, loff_t pos, size_t size)
+				   struct bin_attribute *bin_attr,
+				   char *buffer, loff_t pos, size_t size)
 {
 	int bytes_read = -EINVAL;
 	char *table = NULL;
diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
index d448f8df861..6543cbe83be 100644
--- a/drivers/pci/pci-sysfs.c
+++ b/drivers/pci/pci-sysfs.c
@@ -213,7 +213,8 @@ struct device_attribute pci_dev_attrs[] = {
 };
 
 static ssize_t
-pci_read_config(struct kobject *kobj, char *buf, loff_t off, size_t count)
+pci_read_config(struct kobject *kobj, struct bin_attribute *bin_attr,
+		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;
@@ -285,7 +286,8 @@ pci_read_config(struct kobject *kobj, char *buf, loff_t off, size_t count)
 }
 
 static ssize_t
-pci_write_config(struct kobject *kobj, char *buf, loff_t off, size_t count)
+pci_write_config(struct kobject *kobj, struct bin_attribute *bin_attr,
+		 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;
@@ -352,7 +354,8 @@ pci_write_config(struct kobject *kobj, char *buf, loff_t off, size_t count)
  * callback routine (pci_legacy_read).
  */
 ssize_t
-pci_read_legacy_io(struct kobject *kobj, char *buf, loff_t off, size_t count)
+pci_read_legacy_io(struct kobject *kobj, struct bin_attribute *bin_attr,
+		   char *buf, loff_t off, size_t count)
 {
         struct pci_bus *bus = to_pci_bus(container_of(kobj,
                                                       struct class_device,
@@ -376,7 +379,8 @@ pci_read_legacy_io(struct kobject *kobj, char *buf, loff_t off, size_t count)
  * callback routine (pci_legacy_write).
  */
 ssize_t
-pci_write_legacy_io(struct kobject *kobj, char *buf, loff_t off, size_t count)
+pci_write_legacy_io(struct kobject *kobj, struct bin_attribute *bin_attr,
+		    char *buf, loff_t off, size_t count)
 {
         struct pci_bus *bus = to_pci_bus(container_of(kobj,
 						      struct class_device,
@@ -528,7 +532,8 @@ static inline void pci_remove_resource_files(struct pci_dev *dev) { return; }
  * writing anything except 0 enables it
  */
 static ssize_t
-pci_write_rom(struct kobject *kobj, char *buf, loff_t off, size_t count)
+pci_write_rom(struct kobject *kobj, struct bin_attribute *bin_attr,
+	      char *buf, loff_t off, size_t count)
 {
 	struct pci_dev *pdev = to_pci_dev(container_of(kobj, struct device, kobj));
 
@@ -551,7 +556,8 @@ pci_write_rom(struct kobject *kobj, char *buf, loff_t off, size_t count)
  * device corresponding to @kobj.
  */
 static ssize_t
-pci_read_rom(struct kobject *kobj, char *buf, loff_t off, size_t count)
+pci_read_rom(struct kobject *kobj, struct bin_attribute *bin_attr,
+	     char *buf, loff_t off, size_t count)
 {
 	struct pci_dev *pdev = to_pci_dev(container_of(kobj, struct device, kobj));
 	void __iomem *rom;