diff options
Diffstat (limited to 'drivers/xen/xenfs')
| -rw-r--r-- | drivers/xen/xenfs/Makefile | 4 | ||||
| -rw-r--r-- | drivers/xen/xenfs/super.c | 139 | ||||
| -rw-r--r-- | drivers/xen/xenfs/xenfs.h | 7 | ||||
| -rw-r--r-- | drivers/xen/xenfs/xenstored.c | 68 |
4 files changed, 218 insertions, 0 deletions
diff --git a/drivers/xen/xenfs/Makefile b/drivers/xen/xenfs/Makefile new file mode 100644 index 00000000..b019865f --- /dev/null +++ b/drivers/xen/xenfs/Makefile @@ -0,0 +1,4 @@ +obj-$(CONFIG_XENFS) += xenfs.o + +xenfs-y = super.o +xenfs-$(CONFIG_XEN_DOM0) += xenstored.o diff --git a/drivers/xen/xenfs/super.c b/drivers/xen/xenfs/super.c new file mode 100644 index 00000000..a84b53c0 --- /dev/null +++ b/drivers/xen/xenfs/super.c @@ -0,0 +1,139 @@ +/* + * xenfs.c - a filesystem for passing info between the a domain and + * the hypervisor. + * + * 2008-10-07 Alex Zeffertt Replaced /proc/xen/xenbus with xenfs filesystem + * and /proc/xen compatibility mount point. + * Turned xenfs into a loadable module. + */ + +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/module.h> +#include <linux/fs.h> +#include <linux/magic.h> + +#include <xen/xen.h> + +#include "xenfs.h" +#include "../privcmd.h" +#include "../xenbus/xenbus_comms.h" + +#include <asm/xen/hypervisor.h> + +MODULE_DESCRIPTION("Xen filesystem"); +MODULE_LICENSE("GPL"); + +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_uid = ret->i_gid = 0; + ret->i_blocks = 0; + ret->i_atime = ret->i_mtime = ret->i_ctime = CURRENT_TIME; + } + return ret; +} + +static struct dentry *xenfs_create_file(struct super_block *sb, + struct dentry *parent, + const char *name, + const struct file_operations *fops, + void *data, + int mode) +{ + struct dentry *dentry; + struct inode *inode; + + dentry = d_alloc_name(parent, name); + if (!dentry) + return NULL; + + inode = xenfs_make_inode(sb, S_IFREG | mode); + if (!inode) { + dput(dentry); + return NULL; + } + + inode->i_fop = fops; + inode->i_private = data; + + d_add(dentry, inode); + return dentry; +} + +static ssize_t capabilities_read(struct file *file, char __user *buf, + size_t size, loff_t *off) +{ + char *tmp = ""; + + if (xen_initial_domain()) + tmp = "control_d\n"; + + return simple_read_from_buffer(buf, size, off, tmp, strlen(tmp)); +} + +static const struct file_operations capabilities_file_ops = { + .read = capabilities_read, + .llseek = default_llseek, +}; + +static int xenfs_fill_super(struct super_block *sb, void *data, int silent) +{ + static struct tree_descr xenfs_files[] = { + [1] = {}, + { "xenbus", &xen_xenbus_fops, S_IRUSR|S_IWUSR }, + { "capabilities", &capabilities_file_ops, S_IRUGO }, + { "privcmd", &xen_privcmd_fops, S_IRUSR|S_IWUSR }, + {""}, + }; + int rc; + + rc = simple_fill_super(sb, XENFS_SUPER_MAGIC, xenfs_files); + if (rc < 0) + return rc; + + if (xen_initial_domain()) { + xenfs_create_file(sb, sb->s_root, "xsd_kva", + &xsd_kva_file_ops, NULL, S_IRUSR|S_IWUSR); + xenfs_create_file(sb, sb->s_root, "xsd_port", + &xsd_port_file_ops, NULL, S_IRUSR|S_IWUSR); + } + + return rc; +} + +static struct dentry *xenfs_mount(struct file_system_type *fs_type, + int flags, const char *dev_name, + void *data) +{ + return mount_single(fs_type, flags, data, xenfs_fill_super); +} + +static struct file_system_type xenfs_type = { + .owner = THIS_MODULE, + .name = "xenfs", + .mount = xenfs_mount, + .kill_sb = kill_litter_super, +}; + +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"); + return 0; +} + +static void __exit xenfs_exit(void) +{ + if (xen_domain()) + unregister_filesystem(&xenfs_type); +} + +module_init(xenfs_init); +module_exit(xenfs_exit); + diff --git a/drivers/xen/xenfs/xenfs.h b/drivers/xen/xenfs/xenfs.h new file mode 100644 index 00000000..6b80c777 --- /dev/null +++ b/drivers/xen/xenfs/xenfs.h @@ -0,0 +1,7 @@ +#ifndef _XENFS_XENBUS_H +#define _XENFS_XENBUS_H + +extern const struct file_operations xsd_kva_file_ops; +extern const struct file_operations xsd_port_file_ops; + +#endif /* _XENFS_XENBUS_H */ diff --git a/drivers/xen/xenfs/xenstored.c b/drivers/xen/xenfs/xenstored.c new file mode 100644 index 00000000..fef20dbc --- /dev/null +++ b/drivers/xen/xenfs/xenstored.c @@ -0,0 +1,68 @@ +#include <linux/slab.h> +#include <linux/types.h> +#include <linux/mm.h> +#include <linux/fs.h> + +#include <xen/page.h> + +#include "xenfs.h" +#include "../xenbus/xenbus_comms.h" + +static ssize_t xsd_read(struct file *file, char __user *buf, + size_t size, loff_t *off) +{ + const char *str = (const char *)file->private_data; + return simple_read_from_buffer(buf, size, off, str, strlen(str)); +} + +static int xsd_release(struct inode *inode, struct file *file) +{ + kfree(file->private_data); + return 0; +} + +static int xsd_kva_open(struct inode *inode, struct file *file) +{ + file->private_data = (void *)kasprintf(GFP_KERNEL, "0x%p", + xen_store_interface); + if (!file->private_data) + return -ENOMEM; + return 0; +} + +static int xsd_kva_mmap(struct file *file, struct vm_area_struct *vma) +{ + size_t size = vma->vm_end - vma->vm_start; + + if ((size > PAGE_SIZE) || (vma->vm_pgoff != 0)) + return -EINVAL; + + if (remap_pfn_range(vma, vma->vm_start, + virt_to_pfn(xen_store_interface), + size, vma->vm_page_prot)) + return -EAGAIN; + + return 0; +} + +const struct file_operations xsd_kva_file_ops = { + .open = xsd_kva_open, + .mmap = xsd_kva_mmap, + .read = xsd_read, + .release = xsd_release, +}; + +static int xsd_port_open(struct inode *inode, struct file *file) +{ + file->private_data = (void *)kasprintf(GFP_KERNEL, "%d", + xen_store_evtchn); + if (!file->private_data) + return -ENOMEM; + return 0; +} + +const struct file_operations xsd_port_file_ops = { + .open = xsd_port_open, + .read = xsd_read, + .release = xsd_release, +}; |