/*
- * bin.c - binary file operations for sysfs.
+ * 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/kobject.h>
#include <linux/module.h>
#include <linux/slab.h>
+#include <linux/mutex.h>
+#include <linux/mm.h>
#include <asm/uaccess.h>
-#include <asm/semaphore.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;
+ struct vm_operations_struct *vm_ops;
+ struct file *file;
+ struct hlist_node list;
+};
+
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);
+ struct sysfs_dirent *attr_sd = 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_two(attr_sd))
+ return -ENODEV;
- if (!attr->read)
- return -EIO;
+ rc = -EIO;
+ if (attr->read)
+ rc = attr->read(kobj, attr, buffer, off, count);
- return attr->read(kobj, buffer, off, count);
+ sysfs_put_active_two(attr_sd);
+
+ return rc;
}
static ssize_t
-read(struct file * file, char __user * userbuf, size_t count, loff_t * off)
+read(struct file *file, char __user *userbuf, size_t bytes, loff_t *off)
{
- char *buffer = file->private_data;
+ struct bin_buffer *bb = file->private_data;
struct dentry *dentry = file->f_path.dentry;
int size = dentry->d_inode->i_size;
loff_t offs = *off;
- int ret;
+ int count = min_t(size_t, bytes, PAGE_SIZE);
+ char *temp;
- if (count > PAGE_SIZE)
- count = PAGE_SIZE;
+ if (!bytes)
+ return 0;
if (size) {
if (offs > size)
count = size - offs;
}
- ret = fill_read(dentry, buffer, offs, count);
- if (ret < 0)
- return ret;
- count = ret;
+ temp = kmalloc(count, GFP_KERNEL);
+ if (!temp)
+ return -ENOMEM;
- if (copy_to_user(userbuf, buffer, count))
- return -EFAULT;
+ mutex_lock(&bb->mutex);
+
+ count = fill_read(dentry, bb->buffer, offs, count);
+ if (count < 0) {
+ mutex_unlock(&bb->mutex);
+ goto out_free;
+ }
- pr_debug("offs = %lld, *off = %lld, count = %zd\n", offs, *off, count);
+ 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 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);
+ struct sysfs_dirent *attr_sd = 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_two(attr_sd))
+ return -ENODEV;
- if (!attr->write)
- return -EIO;
+ rc = -EIO;
+ if (attr->write)
+ rc = attr->write(kobj, attr, buffer, offset, count);
- return attr->write(kobj, buffer, offset, count);
+ sysfs_put_active_two(attr_sd);
+
+ return rc;
}
-static ssize_t write(struct file * file, const char __user * userbuf,
- size_t count, loff_t * off)
+static ssize_t write(struct file *file, const char __user *userbuf,
+ size_t bytes, loff_t *off)
{
- char *buffer = file->private_data;
+ struct bin_buffer *bb = file->private_data;
struct dentry *dentry = file->f_path.dentry;
int size = dentry->d_inode->i_size;
loff_t offs = *off;
+ int count = min_t(size_t, bytes, PAGE_SIZE);
+ char *temp;
+
+ if (!bytes)
+ return 0;
- if (count > PAGE_SIZE)
- count = PAGE_SIZE;
if (size) {
if (offs > size)
return 0;
count = size - offs;
}
- if (copy_from_user(buffer, userbuf, count))
- return -EFAULT;
+ 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(dentry, bb->buffer, offs, count);
+ mutex_unlock(&bb->mutex);
- count = flush_write(dentry, buffer, offs, count);
if (count > 0)
*off = offs + count;
+
+ kfree(temp);
return count;
}
-static int mmap(struct file *file, struct vm_area_struct *vma)
+static void bin_vma_open(struct vm_area_struct *vma)
{
- struct dentry *dentry = file->f_path.dentry;
- struct bin_attribute *attr = to_bin_attr(dentry);
- struct kobject *kobj = to_kobj(dentry->d_parent);
+ 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 (!attr->mmap)
+ if (!bb->vm_ops || !bb->vm_ops->open)
+ return;
+
+ if (!sysfs_get_active_two(attr_sd))
+ return;
+
+ bb->vm_ops->open(vma);
+
+ sysfs_put_active_two(attr_sd);
+}
+
+static void bin_vma_close(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 || !bb->vm_ops->close)
+ return;
+
+ if (!sysfs_get_active_two(attr_sd))
+ return;
+
+ bb->vm_ops->close(vma);
+
+ sysfs_put_active_two(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 || !bb->vm_ops->fault)
+ return VM_FAULT_SIGBUS;
+
+ if (!sysfs_get_active_two(attr_sd))
+ return VM_FAULT_SIGBUS;
+
+ ret = bb->vm_ops->fault(vma, vmf);
+
+ sysfs_put_active_two(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 (!bb->vm_ops->page_mkwrite)
+ return 0;
+
+ if (!sysfs_get_active_two(attr_sd))
+ return VM_FAULT_SIGBUS;
+
+ ret = bb->vm_ops->page_mkwrite(vma, vmf);
+
+ sysfs_put_active_two(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 || !bb->vm_ops->access)
+ return -EINVAL;
+
+ if (!sysfs_get_active_two(attr_sd))
return -EINVAL;
- return attr->mmap(kobj, attr, vma);
+ ret = bb->vm_ops->access(vma, addr, buf, len, write);
+
+ sysfs_put_active_two(attr_sd);
+ return ret;
}
-static int open(struct inode * inode, struct file * file)
+#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 || !bb->vm_ops->set_policy)
+ return 0;
+
+ if (!sysfs_get_active_two(attr_sd))
+ return -EINVAL;
+
+ ret = bb->vm_ops->set_policy(vma, new);
+
+ sysfs_put_active_two(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 || !bb->vm_ops->get_policy)
+ return vma->vm_policy;
+
+ if (!sysfs_get_active_two(attr_sd))
+ return vma->vm_policy;
+
+ pol = bb->vm_ops->get_policy(vma, addr);
+
+ sysfs_put_active_two(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 || !bb->vm_ops->migrate)
+ return 0;
+
+ if (!sysfs_get_active_two(attr_sd))
+ return 0;
+
+ ret = bb->vm_ops->migrate(vma, from, to, flags);
+
+ sysfs_put_active_two(attr_sd);
+ return ret;
+}
+#endif
+
+static struct vm_operations_struct bin_vm_ops = {
+ .open = bin_vma_open,
+ .close = bin_vma_close,
+ .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 kobject *kobj = sysfs_get_kobject(file->f_path.dentry->d_parent);
- struct bin_attribute * attr = to_bin_attr(file->f_path.dentry);
- int error = -EINVAL;
+ 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_two(attr_sd))
+ goto out_unlock;
+
+ rc = -EINVAL;
+ if (!attr->mmap)
+ goto out_put;
+
+ rc = attr->mmap(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;
+
+ rc = 0;
+ bb->mmapped = 1;
+ bb->vm_ops = vma->vm_ops;
+ vma->vm_ops = &bin_vm_ops;
+out_put:
+ sysfs_put_active_two(attr_sd);
+out_unlock:
+ mutex_unlock(&bb->mutex);
+
+ return rc;
+}
- if (!kobj || !attr)
- goto Done;
+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;
- /* Grab the module reference for this attribute if we have one */
- error = -ENODEV;
- if (!try_module_get(attr->attr.owner))
- goto Done;
+ /* binary file operations requires both @sd and its parent */
+ if (!sysfs_get_active_two(attr_sd))
+ return -ENODEV;
error = -EACCES;
if ((file->f_mode & FMODE_WRITE) && !(attr->write || attr->mmap))
- goto Error;
+ goto err_out;
if ((file->f_mode & FMODE_READ) && !(attr->read || attr->mmap))
- goto Error;
+ goto err_out;
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)
- kobject_put(kobj);
+ 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_two(attr_sd);
+ return 0;
+
+ err_out:
+ sysfs_put_active_two(attr_sd);
+ kfree(bb);
return error;
}
static int release(struct inode * inode, struct file * file)
{
- struct kobject * kobj = to_kobj(file->f_path.dentry->d_parent);
- struct bin_attribute * attr = to_bin_attr(file->f_path.dentry);
- u8 * buffer = file->private_data;
+ struct bin_buffer *bb = file->private_data;
- kobject_put(kobj);
- module_put(attr->attr.owner);
- kfree(buffer);
+ mutex_lock(&sysfs_bin_lock);
+ hlist_del(&bb->list);
+ mutex_unlock(&sysfs_bin_lock);
+
+ kfree(bb->buffer);
+ kfree(bb);
return 0;
}
.release = release,
};
+
+void unmap_bin_file(struct sysfs_dirent *attr_sd)
+{
+ struct bin_buffer *bb;
+ struct hlist_node *tmp;
+
+ if (sysfs_type(attr_sd) != SYSFS_KOBJ_BIN_ATTR)
+ return;
+
+ mutex_lock(&sysfs_bin_lock);
+
+ hlist_for_each_entry(bb, tmp, &attr_sd->s_bin_attr.buffers, list) {
+ struct inode *inode = bb->file->f_path.dentry->d_inode;
+
+ 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.
int sysfs_create_bin_file(struct kobject * kobj, struct bin_attribute * attr)
{
- BUG_ON(!kobj || !kobj->dentry || !attr);
+ BUG_ON(!kobj || !kobj->sd || !attr);
- return sysfs_add_file(kobj->dentry, &attr->attr, SYSFS_KOBJ_BIN_ATTR);
+ return sysfs_add_file(kobj->sd, &attr->attr, SYSFS_KOBJ_BIN_ATTR);
}
void sysfs_remove_bin_file(struct kobject * kobj, struct bin_attribute * attr)
{
- if (sysfs_hash_and_remove(kobj->dentry, attr->attr.name) < 0) {
- printk(KERN_ERR "%s: "
- "bad dentry or inode or no such file: \"%s\"\n",
- __FUNCTION__, attr->attr.name);
- dump_stack();
- }
+ sysfs_hash_and_remove(kobj->sd, attr->attr.name);
}
EXPORT_SYMBOL_GPL(sysfs_create_bin_file);