Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 24a89b5b authored by Jeremy Fitzhardinge's avatar Jeremy Fitzhardinge Committed by Jeremy Fitzhardinge
Browse files

xen/privcmd: create address space to allow writable mmaps 



These are necessary to allow writeable mmap of the privcmd node to
succeed without being marked read-only for writenotify purposes. Which
in turn is necessary to allow mappings of foreign guest pages

[ Impact: bugfix: allow writable mappings ]

Signed-off-by: default avatarIan Campbell <ian.campbell@citrix.com>
Signed-off-by: default avatarJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
parent 1c5de193

drivers/xen/xenfs/super.c

+38 −4
Original line number Diff line number Diff line
@@ -12,6 +12,8 @@ 
#include <linux/module.h>

#include <linux/fs.h>

#include <linux/magic.h>

#include <linux/mm.h>

#include <linux/backing-dev.h>



#include <xen/xen.h>
@@ -22,12 +24,30 @@ 
MODULE_DESCRIPTION("Xen filesystem");

MODULE_LICENSE("GPL");



static int xenfs_set_page_dirty(struct page *page)

{

	if (!PageDirty(page))

		SetPageDirty(page);

	return 0;

}



static const struct address_space_operations xenfs_aops = {

	.set_page_dirty = xenfs_set_page_dirty,

};



static struct backing_dev_info xenfs_backing_dev_info = {

	.ra_pages	= 0,	/* No readahead */

	.capabilities	= BDI_CAP_NO_ACCT_AND_WRITEBACK,

};



static struct inode *xenfs_make_inode(struct super_block *sb, int mode)

{

	struct inode *ret = new_inode(sb);



	if (ret) {

		ret->i_mode = mode;

		ret->i_mapping->a_ops = &xenfs_aops;

		ret->i_mapping->backing_dev_info = &xenfs_backing_dev_info;

		ret->i_uid = ret->i_gid = 0;

		ret->i_blocks = 0;

		ret->i_atime = ret->i_mtime = ret->i_ctime = CURRENT_TIME;
@@ -119,13 +139,27 @@ static struct file_system_type xenfs_type = { 


static int __init xenfs_init(void)

{

	if (xen_domain())

		return register_filesystem(&xenfs_type);



	printk(KERN_INFO "XENFS: not registering filesystem on non-xen platform\n");

	int err;

	if (!xen_domain()) {

		printk(KERN_INFO "xenfs: not registering filesystem on non-xen platform\n");

		return 0;

	}



	err = register_filesystem(&xenfs_type);

	if (err) {

		printk(KERN_ERR "xenfs: Unable to register filesystem!\n");

		goto out;

	}



	err = bdi_init(&xenfs_backing_dev_info);

	if (err)

		unregister_filesystem(&xenfs_type);



 out:



	return err;

}



static void __exit xenfs_exit(void)

{

	if (xen_domain())