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-rw-r--r--fs/sysfs/bin.c204
1 files changed, 204 insertions, 0 deletions
diff --git a/fs/sysfs/bin.c b/fs/sysfs/bin.c
new file mode 100644
index 000000000000..d4aaa88d0214
--- /dev/null
+++ b/fs/sysfs/bin.c
@@ -0,0 +1,204 @@
+/*
+ * bin.c - binary file operations for sysfs.
+ *
+ * Copyright (c) 2003 Patrick Mochel
+ * Copyright (c) 2003 Matthew Wilcox
+ * Copyright (c) 2004 Silicon Graphics, Inc.
+ */
+
+#undef DEBUG
+
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/kobject.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+
+#include <asm/uaccess.h>
+
+#include "sysfs.h"
+
+static int
+fill_read(struct dentry *dentry, char *buffer, loff_t off, size_t count)
+{
+ struct bin_attribute * attr = to_bin_attr(dentry);
+ struct kobject * kobj = to_kobj(dentry->d_parent);
+
+ if (!attr->read)
+ return -EINVAL;
+
+ return attr->read(kobj, buffer, off, count);
+}
+
+static ssize_t
+read(struct file * file, char __user * userbuf, size_t count, loff_t * off)
+{
+ char *buffer = file->private_data;
+ struct dentry *dentry = file->f_dentry;
+ int size = dentry->d_inode->i_size;
+ loff_t offs = *off;
+ int ret;
+
+ if (count > PAGE_SIZE)
+ count = PAGE_SIZE;
+
+ if (size) {
+ if (offs > size)
+ return 0;
+ if (offs + count > size)
+ count = size - offs;
+ }
+
+ ret = fill_read(dentry, buffer, offs, count);
+ if (ret < 0)
+ return ret;
+ count = ret;
+
+ if (copy_to_user(userbuf, buffer, count))
+ return -EFAULT;
+
+ pr_debug("offs = %lld, *off = %lld, count = %zd\n", offs, *off, count);
+
+ *off = offs + count;
+
+ return count;
+}
+
+static int
+flush_write(struct dentry *dentry, char *buffer, loff_t offset, size_t count)
+{
+ struct bin_attribute *attr = to_bin_attr(dentry);
+ struct kobject *kobj = to_kobj(dentry->d_parent);
+
+ if (!attr->write)
+ return -EINVAL;
+
+ return attr->write(kobj, buffer, offset, count);
+}
+
+static ssize_t write(struct file * file, const char __user * userbuf,
+ size_t count, loff_t * off)
+{
+ char *buffer = file->private_data;
+ struct dentry *dentry = file->f_dentry;
+ int size = dentry->d_inode->i_size;
+ loff_t offs = *off;
+
+ if (count > PAGE_SIZE)
+ count = PAGE_SIZE;
+ if (size) {
+ if (offs > size)
+ return 0;
+ if (offs + count > size)
+ count = size - offs;
+ }
+
+ if (copy_from_user(buffer, userbuf, count))
+ return -EFAULT;
+
+ count = flush_write(dentry, buffer, offs, count);
+ if (count > 0)
+ *off = offs + count;
+ return count;
+}
+
+static int mmap(struct file *file, struct vm_area_struct *vma)
+{
+ struct dentry *dentry = file->f_dentry;
+ struct bin_attribute *attr = to_bin_attr(dentry);
+ struct kobject *kobj = to_kobj(dentry->d_parent);
+
+ if (!attr->mmap)
+ return -EINVAL;
+
+ return attr->mmap(kobj, attr, vma);
+}
+
+static int open(struct inode * inode, struct file * file)
+{
+ struct kobject *kobj = sysfs_get_kobject(file->f_dentry->d_parent);
+ struct bin_attribute * attr = to_bin_attr(file->f_dentry);
+ int error = -EINVAL;
+
+ if (!kobj || !attr)
+ goto Done;
+
+ /* Grab the module reference for this attribute if we have one */
+ error = -ENODEV;
+ if (!try_module_get(attr->attr.owner))
+ goto Done;
+
+ error = -EACCES;
+ if ((file->f_mode & FMODE_WRITE) && !(attr->write || attr->mmap))
+ goto Error;
+ if ((file->f_mode & FMODE_READ) && !(attr->read || attr->mmap))
+ goto Error;
+
+ error = -ENOMEM;
+ file->private_data = kmalloc(PAGE_SIZE, GFP_KERNEL);
+ if (!file->private_data)
+ goto Error;
+
+ error = 0;
+ goto Done;
+
+ Error:
+ module_put(attr->attr.owner);
+ Done:
+ if (error && kobj)
+ kobject_put(kobj);
+ return error;
+}
+
+static int release(struct inode * inode, struct file * file)
+{
+ struct kobject * kobj = to_kobj(file->f_dentry->d_parent);
+ struct bin_attribute * attr = to_bin_attr(file->f_dentry);
+ u8 * buffer = file->private_data;
+
+ if (kobj)
+ kobject_put(kobj);
+ module_put(attr->attr.owner);
+ kfree(buffer);
+ return 0;
+}
+
+struct file_operations bin_fops = {
+ .read = read,
+ .write = write,
+ .mmap = mmap,
+ .llseek = generic_file_llseek,
+ .open = open,
+ .release = release,
+};
+
+/**
+ * sysfs_create_bin_file - create binary file for object.
+ * @kobj: object.
+ * @attr: attribute descriptor.
+ *
+ */
+
+int sysfs_create_bin_file(struct kobject * kobj, struct bin_attribute * attr)
+{
+ BUG_ON(!kobj || !kobj->dentry || !attr);
+
+ return sysfs_add_file(kobj->dentry, &attr->attr, SYSFS_KOBJ_BIN_ATTR);
+}
+
+
+/**
+ * sysfs_remove_bin_file - remove binary file for object.
+ * @kobj: object.
+ * @attr: attribute descriptor.
+ *
+ */
+
+int sysfs_remove_bin_file(struct kobject * kobj, struct bin_attribute * attr)
+{
+ sysfs_hash_and_remove(kobj->dentry,attr->attr.name);
+ return 0;
+}
+
+EXPORT_SYMBOL_GPL(sysfs_create_bin_file);
+EXPORT_SYMBOL_GPL(sysfs_remove_bin_file);