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>

1 files changed, 12 insertions, 6 deletions

diff --git a/drivers/scsi/ipr.c b/drivers/scsi/ipr.c
index fa6ff295e568..4a3083ea59d5 100644
--- a/drivers/scsi/ipr.c
+++ b/drivers/scsi/ipr.c
@@ -2465,6 +2465,7 @@ restart:
 /**
  * ipr_read_trace - Dump the adapter trace
  * @kobj:               kobject struct
+ * @bin_attr:           bin_attribute struct
  * @buf:                buffer
  * @off:                offset
  * @count:              buffer size
@@ -2472,8 +2473,9 @@ restart:
  * Return value:
  *      number of bytes printed to buffer
  **/
-static ssize_t ipr_read_trace(struct kobject *kobj, char *buf,
-                              loff_t off, size_t count)
+static ssize_t ipr_read_trace(struct kobject *kobj,
+                              struct bin_attribute *bin_attr,
+                              char *buf, loff_t off, size_t count)
 {
         struct class_device *cdev = container_of(kobj,struct class_device,kobj);
         struct Scsi_Host *shost = class_to_shost(cdev);
@@ -3166,6 +3168,7 @@ static struct class_device_attribute *ipr_ioa_attrs[] = {
 /**
  * ipr_read_dump - Dump the adapter
  * @kobj:               kobject struct
+ * @bin_attr:           bin_attribute struct
  * @buf:                buffer
  * @off:                offset
  * @count:              buffer size
@@ -3173,8 +3176,9 @@ static struct class_device_attribute *ipr_ioa_attrs[] = {
  * Return value:
  *      number of bytes printed to buffer
  **/
-static ssize_t ipr_read_dump(struct kobject *kobj, char *buf,
-                              loff_t off, size_t count)
+static ssize_t ipr_read_dump(struct kobject *kobj,
+                             struct bin_attribute *bin_attr,
+                             char *buf, loff_t off, size_t count)
 {
         struct class_device *cdev = container_of(kobj,struct class_device,kobj);
         struct Scsi_Host *shost = class_to_shost(cdev);
@@ -3327,6 +3331,7 @@ static int ipr_free_dump(struct ipr_ioa_cfg *ioa_cfg)
 /**
  * ipr_write_dump - Setup dump state of adapter
  * @kobj:               kobject struct
+ * @bin_attr:           bin_attribute struct
  * @buf:                buffer
  * @off:                offset
  * @count:              buffer size
@@ -3334,8 +3339,9 @@ static int ipr_free_dump(struct ipr_ioa_cfg *ioa_cfg)
  * Return value:
  *      number of bytes printed to buffer
  **/
-static ssize_t ipr_write_dump(struct kobject *kobj, char *buf,
-                              loff_t off, size_t count)
+static ssize_t ipr_write_dump(struct kobject *kobj,
+                              struct bin_attribute *bin_attr,
+                              char *buf, loff_t off, size_t count)
 {
         struct class_device *cdev = container_of(kobj,struct class_device,kobj);
         struct Scsi_Host *shost = class_to_shost(cdev);