3 files changed, 174 insertions, 13 deletions

diff --git a/fs/sysfs/bin.c b/fs/sysfs/bin.c
index f2c478c3424e..96cc2bf6a84e 100644
--- a/fs/sysfs/bin.c
+++ b/fs/sysfs/bin.c
@@ -21,15 +21,28 @@
 #include <linux/module.h>
 #include <linux/slab.h>
 #include <linux/mutex.h>
+#include <linux/mm.h>
 
 #include <asm/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;
+        struct mutex                    mutex;
+        void                            *buffer;
+        int                             mmapped;
+        struct vm_operations_struct     *vm_ops;
+        struct file                     *file;
+        struct hlist_node               list;
 };
 
 static int
@@ -168,29 +181,148 @@ out_free:
         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 || !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 page *page)
+{
+        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->page_mkwrite)
+                return -EINVAL;
+
+        if (!sysfs_get_active_two(attr_sd))
+                return -EINVAL;
+
+        ret = bb->vm_ops->page_mkwrite(vma, page);
+
+        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;
+
+        ret = bb->vm_ops->access(vma, addr, buf, len, write);
+
+        sysfs_put_active_two(attr_sd);
+        return ret;
+}
+
+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,
+};
+
 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;
+        struct vm_operations_struct *vm_ops;
         int rc;
 
         mutex_lock(&bb->mutex);
 
         /* need attr_sd for attr, its parent for kobj */
+        rc = -ENODEV;
         if (!sysfs_get_active_two(attr_sd))
-                return -ENODEV;
+                goto out_unlock;
 
         rc = -EINVAL;
-        if (attr->mmap)
-                rc = attr->mmap(kobj, attr, vma);
+        if (!attr->mmap)
+                goto out_put;
 
-        if (rc == 0 && !bb->mmapped)
-                bb->mmapped = 1;
-        else
-                sysfs_put_active_two(attr_sd);
+        rc = attr->mmap(kobj, attr, vma);
+        vm_ops = vma->vm_ops;
+        vma->vm_ops = &bin_vm_ops;
+        if (rc)
+                goto out_put;
 
+        rc = -EINVAL;
+        if (bb->mmapped && bb->vm_ops != vma->vm_ops)
+                goto out_put;
+
+#ifdef CONFIG_NUMA
+        rc = -EINVAL;
+        if (vm_ops && ((vm_ops->set_policy || vm_ops->get_policy || vm_ops->migrate)))
+                goto out_put;
+#endif
+
+        rc = 0;
+        bb->mmapped = 1;
+        bb->vm_ops = vm_ops;
+out_put:
+        sysfs_put_active_two(attr_sd);
+out_unlock:
         mutex_unlock(&bb->mutex);
 
         return rc;
@@ -223,8 +355,13 @@ static int open(struct inode * inode, struct file * file)
                 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;
@@ -237,11 +374,12 @@ static int open(struct inode * inode, struct file * file)
 
 static int release(struct inode * inode, struct file * file)
 {
-        struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
         struct bin_buffer *bb = file->private_data;
 
-        if (bb->mmapped)
-                sysfs_put_active_two(attr_sd);
+        mutex_lock(&sysfs_bin_lock);
+        hlist_del(&bb->list);
+        mutex_unlock(&sysfs_bin_lock);
+
         kfree(bb->buffer);
         kfree(bb);
         return 0;
@@ -256,6 +394,26 @@ const struct file_operations bin_fops = {
         .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.
diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c
index f13d852ab3c1..66aeb4fff0c3 100644
--- a/fs/sysfs/dir.c
+++ b/fs/sysfs/dir.c
@@ -609,6 +609,7 @@ void sysfs_addrm_finish(struct sysfs_addrm_cxt *acxt)
 
                 sysfs_drop_dentry(sd);
                 sysfs_deactivate(sd);
+                unmap_bin_file(sd);
                 sysfs_put(sd);
         }
 }
diff --git a/fs/sysfs/sysfs.h b/fs/sysfs/sysfs.h
index 9055d04e4ab0..3fa0d98481e2 100644
--- a/fs/sysfs/sysfs.h
+++ b/fs/sysfs/sysfs.h
@@ -28,6 +28,7 @@ struct sysfs_elem_attr {
 
 struct sysfs_elem_bin_attr {
         struct bin_attribute    *bin_attr;
+        struct hlist_head       buffers;
 };
 
 /*
@@ -164,6 +165,7 @@ int sysfs_add_file_mode(struct sysfs_dirent *dir_sd,
  * bin.c
  */
 extern const struct file_operations bin_fops;
+void unmap_bin_file(struct sysfs_dirent *attr_sd);
 
 /*
  * symlink.c