Rewind v3.13-rc3+ (78fd82238d0e5716) to v3.12

1 files changed, 502 insertions, 0 deletions

diff --git a/fs/sysfs/bin.c b/fs/sysfs/bin.c
new file mode 100644
index 0000000..c590cab
--- /dev/null
+++ b/fs/sysfs/bin.c
@@ -0,0 +1,502 @@
+/*
+ * fs/sysfs/bin.c - sysfs binary file implementation
+ *
+ * Copyright (c) 2003 Patrick Mochel
+ * Copyright (c) 2003 Matthew Wilcox
+ * Copyright (c) 2004 Silicon Graphics, Inc.
+ * Copyright (c) 2007 SUSE Linux Products GmbH
+ * Copyright (c) 2007 Tejun Heo <teheo@suse.de>
+ *
+ * This file is released under the GPLv2.
+ *
+ * Please see Documentation/filesystems/sysfs.txt for more information.
+ */
+
+#undef DEBUG
+
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/kernel.h>
+#include <linux/kobject.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/mutex.h>
+#include <linux/mm.h>
+#include <linux/uaccess.h>
+
+#include "sysfs.h"
+
+/*
+ * There's one bin_buffer for each open file.
+ *
+ * filp->private_data points to bin_buffer and
+ * sysfs_dirent->s_bin_attr.buffers points to a the bin_buffer s
+ * sysfs_dirent->s_bin_attr.buffers is protected by sysfs_bin_lock
+ */
+static DEFINE_MUTEX(sysfs_bin_lock);
+
+struct bin_buffer {
+	struct mutex			mutex;
+	void				*buffer;
+	int				mmapped;
+	const struct vm_operations_struct *vm_ops;
+	struct file			*file;
+	struct hlist_node		list;
+};
+
+static int
+fill_read(struct file *file, char *buffer, loff_t off, size_t count)
+{
+	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
+	struct bin_attribute *attr = attr_sd->s_bin_attr.bin_attr;
+	struct kobject *kobj = attr_sd->s_parent->s_dir.kobj;
+	int rc;
+
+	/* need attr_sd for attr, its parent for kobj */
+	if (!sysfs_get_active(attr_sd))
+		return -ENODEV;
+
+	rc = -EIO;
+	if (attr->read)
+		rc = attr->read(file, kobj, attr, buffer, off, count);
+
+	sysfs_put_active(attr_sd);
+
+	return rc;
+}
+
+static ssize_t
+read(struct file *file, char __user *userbuf, size_t bytes, loff_t *off)
+{
+	struct bin_buffer *bb = file->private_data;
+	int size = file_inode(file)->i_size;
+	loff_t offs = *off;
+	int count = min_t(size_t, bytes, PAGE_SIZE);
+	char *temp;
+
+	if (!bytes)
+		return 0;
+
+	if (size) {
+		if (offs > size)
+			return 0;
+		if (offs + count > size)
+			count = size - offs;
+	}
+
+	temp = kmalloc(count, GFP_KERNEL);
+	if (!temp)
+		return -ENOMEM;
+
+	mutex_lock(&bb->mutex);
+
+	count = fill_read(file, bb->buffer, offs, count);
+	if (count < 0) {
+		mutex_unlock(&bb->mutex);
+		goto out_free;
+	}
+
+	memcpy(temp, bb->buffer, count);
+
+	mutex_unlock(&bb->mutex);
+
+	if (copy_to_user(userbuf, temp, count)) {
+		count = -EFAULT;
+		goto out_free;
+	}
+
+	pr_debug("offs = %lld, *off = %lld, count = %d\n", offs, *off, count);
+
+	*off = offs + count;
+
+ out_free:
+	kfree(temp);
+	return count;
+}
+
+static int
+flush_write(struct file *file, char *buffer, loff_t offset, size_t count)
+{
+	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
+	struct bin_attribute *attr = attr_sd->s_bin_attr.bin_attr;
+	struct kobject *kobj = attr_sd->s_parent->s_dir.kobj;
+	int rc;
+
+	/* need attr_sd for attr, its parent for kobj */
+	if (!sysfs_get_active(attr_sd))
+		return -ENODEV;
+
+	rc = -EIO;
+	if (attr->write)
+		rc = attr->write(file, kobj, attr, buffer, offset, count);
+
+	sysfs_put_active(attr_sd);
+
+	return rc;
+}
+
+static ssize_t write(struct file *file, const char __user *userbuf,
+		     size_t bytes, loff_t *off)
+{
+	struct bin_buffer *bb = file->private_data;
+	int size = file_inode(file)->i_size;
+	loff_t offs = *off;
+	int count = min_t(size_t, bytes, PAGE_SIZE);
+	char *temp;
+
+	if (!bytes)
+		return 0;
+
+	if (size) {
+		if (offs > size)
+			return 0;
+		if (offs + count > size)
+			count = size - offs;
+	}
+
+	temp = memdup_user(userbuf, count);
+	if (IS_ERR(temp))
+		return PTR_ERR(temp);
+
+	mutex_lock(&bb->mutex);
+
+	memcpy(bb->buffer, temp, count);
+
+	count = flush_write(file, bb->buffer, offs, count);
+	mutex_unlock(&bb->mutex);
+
+	if (count > 0)
+		*off = offs + count;
+
+	kfree(temp);
+	return count;
+}
+
+static void bin_vma_open(struct vm_area_struct *vma)
+{
+	struct file *file = vma->vm_file;
+	struct bin_buffer *bb = file->private_data;
+	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
+
+	if (!bb->vm_ops)
+		return;
+
+	if (!sysfs_get_active(attr_sd))
+		return;
+
+	if (bb->vm_ops->open)
+		bb->vm_ops->open(vma);
+
+	sysfs_put_active(attr_sd);
+}
+
+static int bin_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
+{
+	struct file *file = vma->vm_file;
+	struct bin_buffer *bb = file->private_data;
+	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
+	int ret;
+
+	if (!bb->vm_ops)
+		return VM_FAULT_SIGBUS;
+
+	if (!sysfs_get_active(attr_sd))
+		return VM_FAULT_SIGBUS;
+
+	ret = VM_FAULT_SIGBUS;
+	if (bb->vm_ops->fault)
+		ret = bb->vm_ops->fault(vma, vmf);
+
+	sysfs_put_active(attr_sd);
+	return ret;
+}
+
+static int bin_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
+{
+	struct file *file = vma->vm_file;
+	struct bin_buffer *bb = file->private_data;
+	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
+	int ret;
+
+	if (!bb->vm_ops)
+		return VM_FAULT_SIGBUS;
+
+	if (!sysfs_get_active(attr_sd))
+		return VM_FAULT_SIGBUS;
+
+	ret = 0;
+	if (bb->vm_ops->page_mkwrite)
+		ret = bb->vm_ops->page_mkwrite(vma, vmf);
+	else
+		file_update_time(file);
+
+	sysfs_put_active(attr_sd);
+	return ret;
+}
+
+static int bin_access(struct vm_area_struct *vma, unsigned long addr,
+		  void *buf, int len, int write)
+{
+	struct file *file = vma->vm_file;
+	struct bin_buffer *bb = file->private_data;
+	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
+	int ret;
+
+	if (!bb->vm_ops)
+		return -EINVAL;
+
+	if (!sysfs_get_active(attr_sd))
+		return -EINVAL;
+
+	ret = -EINVAL;
+	if (bb->vm_ops->access)
+		ret = bb->vm_ops->access(vma, addr, buf, len, write);
+
+	sysfs_put_active(attr_sd);
+	return ret;
+}
+
+#ifdef CONFIG_NUMA
+static int bin_set_policy(struct vm_area_struct *vma, struct mempolicy *new)
+{
+	struct file *file = vma->vm_file;
+	struct bin_buffer *bb = file->private_data;
+	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
+	int ret;
+
+	if (!bb->vm_ops)
+		return 0;
+
+	if (!sysfs_get_active(attr_sd))
+		return -EINVAL;
+
+	ret = 0;
+	if (bb->vm_ops->set_policy)
+		ret = bb->vm_ops->set_policy(vma, new);
+
+	sysfs_put_active(attr_sd);
+	return ret;
+}
+
+static struct mempolicy *bin_get_policy(struct vm_area_struct *vma,
+					unsigned long addr)
+{
+	struct file *file = vma->vm_file;
+	struct bin_buffer *bb = file->private_data;
+	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
+	struct mempolicy *pol;
+
+	if (!bb->vm_ops)
+		return vma->vm_policy;
+
+	if (!sysfs_get_active(attr_sd))
+		return vma->vm_policy;
+
+	pol = vma->vm_policy;
+	if (bb->vm_ops->get_policy)
+		pol = bb->vm_ops->get_policy(vma, addr);
+
+	sysfs_put_active(attr_sd);
+	return pol;
+}
+
+static int bin_migrate(struct vm_area_struct *vma, const nodemask_t *from,
+			const nodemask_t *to, unsigned long flags)
+{
+	struct file *file = vma->vm_file;
+	struct bin_buffer *bb = file->private_data;
+	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
+	int ret;
+
+	if (!bb->vm_ops)
+		return 0;
+
+	if (!sysfs_get_active(attr_sd))
+		return 0;
+
+	ret = 0;
+	if (bb->vm_ops->migrate)
+		ret = bb->vm_ops->migrate(vma, from, to, flags);
+
+	sysfs_put_active(attr_sd);
+	return ret;
+}
+#endif
+
+static const struct vm_operations_struct bin_vm_ops = {
+	.open		= bin_vma_open,
+	.fault		= bin_fault,
+	.page_mkwrite	= bin_page_mkwrite,
+	.access		= bin_access,
+#ifdef CONFIG_NUMA
+	.set_policy	= bin_set_policy,
+	.get_policy	= bin_get_policy,
+	.migrate	= bin_migrate,
+#endif
+};
+
+static int mmap(struct file *file, struct vm_area_struct *vma)
+{
+	struct bin_buffer *bb = file->private_data;
+	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
+	struct bin_attribute *attr = attr_sd->s_bin_attr.bin_attr;
+	struct kobject *kobj = attr_sd->s_parent->s_dir.kobj;
+	int rc;
+
+	mutex_lock(&bb->mutex);
+
+	/* need attr_sd for attr, its parent for kobj */
+	rc = -ENODEV;
+	if (!sysfs_get_active(attr_sd))
+		goto out_unlock;
+
+	rc = -EINVAL;
+	if (!attr->mmap)
+		goto out_put;
+
+	rc = attr->mmap(file, kobj, attr, vma);
+	if (rc)
+		goto out_put;
+
+	/*
+	 * PowerPC's pci_mmap of legacy_mem uses shmem_zero_setup()
+	 * to satisfy versions of X which crash if the mmap fails: that
+	 * substitutes a new vm_file, and we don't then want bin_vm_ops.
+	 */
+	if (vma->vm_file != file)
+		goto out_put;
+
+	rc = -EINVAL;
+	if (bb->mmapped && bb->vm_ops != vma->vm_ops)
+		goto out_put;
+
+	/*
+	 * It is not possible to successfully wrap close.
+	 * So error if someone is trying to use close.
+	 */
+	rc = -EINVAL;
+	if (vma->vm_ops && vma->vm_ops->close)
+		goto out_put;
+
+	rc = 0;
+	bb->mmapped = 1;
+	bb->vm_ops = vma->vm_ops;
+	vma->vm_ops = &bin_vm_ops;
+out_put:
+	sysfs_put_active(attr_sd);
+out_unlock:
+	mutex_unlock(&bb->mutex);
+
+	return rc;
+}
+
+static int open(struct inode *inode, struct file *file)
+{
+	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
+	struct bin_attribute *attr = attr_sd->s_bin_attr.bin_attr;
+	struct bin_buffer *bb = NULL;
+	int error;
+
+	/* binary file operations requires both @sd and its parent */
+	if (!sysfs_get_active(attr_sd))
+		return -ENODEV;
+
+	error = -EACCES;
+	if ((file->f_mode & FMODE_WRITE) && !(attr->write || attr->mmap))
+		goto err_out;
+	if ((file->f_mode & FMODE_READ) && !(attr->read || attr->mmap))
+		goto err_out;
+
+	error = -ENOMEM;
+	bb = kzalloc(sizeof(*bb), GFP_KERNEL);
+	if (!bb)
+		goto err_out;
+
+	bb->buffer = kmalloc(PAGE_SIZE, GFP_KERNEL);
+	if (!bb->buffer)
+		goto err_out;
+
+	mutex_init(&bb->mutex);
+	bb->file = file;
+	file->private_data = bb;
+
+	mutex_lock(&sysfs_bin_lock);
+	hlist_add_head(&bb->list, &attr_sd->s_bin_attr.buffers);
+	mutex_unlock(&sysfs_bin_lock);
+
+	/* open succeeded, put active references */
+	sysfs_put_active(attr_sd);
+	return 0;
+
+ err_out:
+	sysfs_put_active(attr_sd);
+	kfree(bb);
+	return error;
+}
+
+static int release(struct inode *inode, struct file *file)
+{
+	struct bin_buffer *bb = file->private_data;
+
+	mutex_lock(&sysfs_bin_lock);
+	hlist_del(&bb->list);
+	mutex_unlock(&sysfs_bin_lock);
+
+	kfree(bb->buffer);
+	kfree(bb);
+	return 0;
+}
+
+const struct file_operations bin_fops = {
+	.read		= read,
+	.write		= write,
+	.mmap		= mmap,
+	.llseek		= generic_file_llseek,
+	.open		= open,
+	.release	= release,
+};
+
+
+void unmap_bin_file(struct sysfs_dirent *attr_sd)
+{
+	struct bin_buffer *bb;
+
+	if (sysfs_type(attr_sd) != SYSFS_KOBJ_BIN_ATTR)
+		return;
+
+	mutex_lock(&sysfs_bin_lock);
+
+	hlist_for_each_entry(bb, &attr_sd->s_bin_attr.buffers, list) {
+		struct inode *inode = file_inode(bb->file);
+
+		unmap_mapping_range(inode->i_mapping, 0, 0, 1);
+	}
+
+	mutex_unlock(&sysfs_bin_lock);
+}
+
+/**
+ *	sysfs_create_bin_file - create binary file for object.
+ *	@kobj:	object.
+ *	@attr:	attribute descriptor.
+ */
+int sysfs_create_bin_file(struct kobject *kobj,
+			  const struct bin_attribute *attr)
+{
+	BUG_ON(!kobj || !kobj->sd || !attr);
+
+	return sysfs_add_file(kobj->sd, &attr->attr, SYSFS_KOBJ_BIN_ATTR);
+}
+EXPORT_SYMBOL_GPL(sysfs_create_bin_file);
+
+/**
+ *	sysfs_remove_bin_file - remove binary file for object.
+ *	@kobj:	object.
+ *	@attr:	attribute descriptor.
+ */
+void sysfs_remove_bin_file(struct kobject *kobj,
+			   const struct bin_attribute *attr)
+{
+	sysfs_hash_and_remove(kobj->sd, NULL, attr->attr.name);
+}
+EXPORT_SYMBOL_GPL(sysfs_remove_bin_file);