forked from luck/tmp_suning_uos_patched
xen: add xenfs to allow usermode <-> Xen interaction
The xenfs filesystem exports various interfaces to usermode. Initially this exports a file to allow usermode to interact with xenbus/xenstore. Traditionally this appeared in /proc/xen. Rather than extending procfs, this patch adds a backward-compat mountpoint on /proc/xen, and provides a xenfs filesystem which can be mounted there. Signed-off-by: Alex Zeffertt <alex.zeffertt@eu.citrix.com> Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
parent
d8220347da
commit
1107ba885e
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@ -17,3 +17,27 @@ config XEN_SCRUB_PAGES
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is not accidentally visible to other domains. Is it more
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secure, but slightly less efficient.
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If in doubt, say yes.
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config XENFS
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tristate "Xen filesystem"
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depends on XEN
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default y
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help
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The xen filesystem provides a way for domains to share
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information with each other and with the hypervisor.
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For example, by reading and writing the "xenbus" file, guests
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may pass arbitrary information to the initial domain.
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If in doubt, say yes.
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config XEN_COMPAT_XENFS
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bool "Create compatibility mount point /proc/xen"
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depends on XENFS
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default y
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help
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The old xenstore userspace tools expect to find "xenbus"
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under /proc/xen, but "xenbus" is now found at the root of the
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xenfs filesystem. Selecting this causes the kernel to create
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the compatibilty mount point /proc/xen if it is running on
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a xen platform.
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If in doubt, say yes.
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@ -1,5 +1,7 @@
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obj-y += grant-table.o features.o events.o manage.o
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obj-y += xenbus/
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obj-$(CONFIG_HOTPLUG_CPU) += cpu_hotplug.o
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obj-$(CONFIG_XEN_XENCOMM) += xencomm.o
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obj-$(CONFIG_XEN_BALLOON) += balloon.o
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obj-$(CONFIG_XENFS) += xenfs/
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@ -40,6 +40,7 @@
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#include <linux/ctype.h>
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#include <linux/fcntl.h>
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#include <linux/mm.h>
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#include <linux/proc_fs.h>
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#include <linux/notifier.h>
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#include <linux/kthread.h>
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#include <linux/mutex.h>
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@ -55,7 +56,10 @@
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#include "xenbus_comms.h"
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#include "xenbus_probe.h"
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int xen_store_evtchn;
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EXPORT_SYMBOL(xen_store_evtchn);
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struct xenstore_domain_interface *xen_store_interface;
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static unsigned long xen_store_mfn;
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@ -166,6 +170,9 @@ static int read_backend_details(struct xenbus_device *xendev)
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return read_otherend_details(xendev, "backend-id", "backend");
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}
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static struct device_attribute xenbus_dev_attrs[] = {
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__ATTR_NULL
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};
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/* Bus type for frontend drivers. */
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static struct xen_bus_type xenbus_frontend = {
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@ -174,12 +181,13 @@ static struct xen_bus_type xenbus_frontend = {
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.get_bus_id = frontend_bus_id,
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.probe = xenbus_probe_frontend,
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.bus = {
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.name = "xen",
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.match = xenbus_match,
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.uevent = xenbus_uevent,
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.probe = xenbus_dev_probe,
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.remove = xenbus_dev_remove,
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.shutdown = xenbus_dev_shutdown,
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.name = "xen",
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.match = xenbus_match,
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.uevent = xenbus_uevent,
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.probe = xenbus_dev_probe,
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.remove = xenbus_dev_remove,
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.shutdown = xenbus_dev_shutdown,
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.dev_attrs = xenbus_dev_attrs,
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},
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};
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@ -852,6 +860,14 @@ static int __init xenbus_probe_init(void)
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if (!xen_initial_domain())
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xenbus_probe(NULL);
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#ifdef CONFIG_XEN_COMPAT_XENFS
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/*
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* Create xenfs mountpoint in /proc for compatibility with
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* utilities that expect to find "xenbus" under "/proc/xen".
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*/
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proc_mkdir("xen", NULL);
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#endif
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return 0;
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out_unreg_back:
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@ -184,6 +184,7 @@ void *xenbus_dev_request_and_reply(struct xsd_sockmsg *msg)
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return ret;
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}
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EXPORT_SYMBOL(xenbus_dev_request_and_reply);
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/* Send message to xs, get kmalloc'ed reply. ERR_PTR() on error. */
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static void *xs_talkv(struct xenbus_transaction t,
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3
drivers/xen/xenfs/Makefile
Normal file
3
drivers/xen/xenfs/Makefile
Normal file
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@ -0,0 +1,3 @@
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obj-$(CONFIG_XENFS) += xenfs.o
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xenfs-objs = super.o xenbus.o
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64
drivers/xen/xenfs/super.c
Normal file
64
drivers/xen/xenfs/super.c
Normal file
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@ -0,0 +1,64 @@
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/*
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* xenfs.c - a filesystem for passing info between the a domain and
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* the hypervisor.
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*
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* 2008-10-07 Alex Zeffertt Replaced /proc/xen/xenbus with xenfs filesystem
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* and /proc/xen compatibility mount point.
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* Turned xenfs into a loadable module.
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*/
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#include <linux/kernel.h>
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#include <linux/errno.h>
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#include <linux/module.h>
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#include <linux/fs.h>
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#include <linux/magic.h>
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#include "xenfs.h"
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#include <asm/xen/hypervisor.h>
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MODULE_DESCRIPTION("Xen filesystem");
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MODULE_LICENSE("GPL");
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static int xenfs_fill_super(struct super_block *sb, void *data, int silent)
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{
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static struct tree_descr xenfs_files[] = {
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[2] = {"xenbus", &xenbus_file_ops, S_IRUSR|S_IWUSR},
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{""},
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};
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return simple_fill_super(sb, XENFS_SUPER_MAGIC, xenfs_files);
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}
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static int xenfs_get_sb(struct file_system_type *fs_type,
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int flags, const char *dev_name,
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void *data, struct vfsmount *mnt)
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{
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return get_sb_single(fs_type, flags, data, xenfs_fill_super, mnt);
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}
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static struct file_system_type xenfs_type = {
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.owner = THIS_MODULE,
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.name = "xenfs",
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.get_sb = xenfs_get_sb,
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.kill_sb = kill_litter_super,
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};
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static int __init xenfs_init(void)
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{
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if (xen_pv_domain())
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return register_filesystem(&xenfs_type);
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printk(KERN_INFO "XENFS: not registering filesystem on non-xen platform\n");
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return 0;
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}
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static void __exit xenfs_exit(void)
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{
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if (xen_pv_domain())
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unregister_filesystem(&xenfs_type);
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}
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module_init(xenfs_init);
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module_exit(xenfs_exit);
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593
drivers/xen/xenfs/xenbus.c
Normal file
593
drivers/xen/xenfs/xenbus.c
Normal file
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@ -0,0 +1,593 @@
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/*
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* Driver giving user-space access to the kernel's xenbus connection
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* to xenstore.
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*
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* Copyright (c) 2005, Christian Limpach
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* Copyright (c) 2005, Rusty Russell, IBM Corporation
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License version 2
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* as published by the Free Software Foundation; or, when distributed
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* separately from the Linux kernel or incorporated into other
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* software packages, subject to the following license:
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*
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* Permission is hereby granted, free of charge, to any person obtaining a copy
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* of this source file (the "Software"), to deal in the Software without
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* restriction, including without limitation the rights to use, copy, modify,
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* merge, publish, distribute, sublicense, and/or sell copies of the Software,
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* and to permit persons to whom the Software is furnished to do so, subject to
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* the following conditions:
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*
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* The above copyright notice and this permission notice shall be included in
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* all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
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* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
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* IN THE SOFTWARE.
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*
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* Changes:
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* 2008-10-07 Alex Zeffertt Replaced /proc/xen/xenbus with xenfs filesystem
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* and /proc/xen compatibility mount point.
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* Turned xenfs into a loadable module.
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*/
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#include <linux/kernel.h>
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#include <linux/errno.h>
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#include <linux/uio.h>
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#include <linux/notifier.h>
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#include <linux/wait.h>
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#include <linux/fs.h>
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#include <linux/poll.h>
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#include <linux/mutex.h>
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#include <linux/spinlock.h>
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#include <linux/mount.h>
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#include <linux/pagemap.h>
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#include <linux/uaccess.h>
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#include <linux/init.h>
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#include <linux/namei.h>
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#include <linux/string.h>
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#include "xenfs.h"
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#include "../xenbus/xenbus_comms.h"
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#include <xen/xenbus.h>
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#include <asm/xen/hypervisor.h>
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/*
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* An element of a list of outstanding transactions, for which we're
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* still waiting a reply.
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*/
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struct xenbus_transaction_holder {
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struct list_head list;
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struct xenbus_transaction handle;
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};
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/*
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* A buffer of data on the queue.
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*/
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struct read_buffer {
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struct list_head list;
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unsigned int cons;
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unsigned int len;
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char msg[];
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};
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struct xenbus_file_priv {
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/*
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* msgbuffer_mutex is held while partial requests are built up
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* and complete requests are acted on. It therefore protects
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* the "transactions" and "watches" lists, and the partial
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* request length and buffer.
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*
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* reply_mutex protects the reply being built up to return to
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* usermode. It nests inside msgbuffer_mutex but may be held
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* alone during a watch callback.
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*/
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struct mutex msgbuffer_mutex;
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/* In-progress transactions */
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struct list_head transactions;
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/* Active watches. */
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struct list_head watches;
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/* Partial request. */
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unsigned int len;
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union {
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struct xsd_sockmsg msg;
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char buffer[PAGE_SIZE];
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} u;
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/* Response queue. */
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struct mutex reply_mutex;
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struct list_head read_buffers;
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wait_queue_head_t read_waitq;
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};
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/* Read out any raw xenbus messages queued up. */
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static ssize_t xenbus_file_read(struct file *filp,
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char __user *ubuf,
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size_t len, loff_t *ppos)
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{
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struct xenbus_file_priv *u = filp->private_data;
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struct read_buffer *rb;
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unsigned i;
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int ret;
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mutex_lock(&u->reply_mutex);
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while (list_empty(&u->read_buffers)) {
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mutex_unlock(&u->reply_mutex);
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ret = wait_event_interruptible(u->read_waitq,
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!list_empty(&u->read_buffers));
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if (ret)
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return ret;
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mutex_lock(&u->reply_mutex);
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}
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rb = list_entry(u->read_buffers.next, struct read_buffer, list);
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i = 0;
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while (i < len) {
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unsigned sz = min((unsigned)len - i, rb->len - rb->cons);
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ret = copy_to_user(ubuf + i, &rb->msg[rb->cons], sz);
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i += sz - ret;
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rb->cons += sz - ret;
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if (ret != sz) {
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if (i == 0)
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i = -EFAULT;
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goto out;
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}
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/* Clear out buffer if it has been consumed */
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if (rb->cons == rb->len) {
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list_del(&rb->list);
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kfree(rb);
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if (list_empty(&u->read_buffers))
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break;
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rb = list_entry(u->read_buffers.next,
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struct read_buffer, list);
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}
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}
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out:
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mutex_unlock(&u->reply_mutex);
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return i;
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}
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/*
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* Add a buffer to the queue. Caller must hold the appropriate lock
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* if the queue is not local. (Commonly the caller will build up
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* multiple queued buffers on a temporary local list, and then add it
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* to the appropriate list under lock once all the buffers have een
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* successfully allocated.)
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*/
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static int queue_reply(struct list_head *queue, const void *data, size_t len)
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{
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struct read_buffer *rb;
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if (len == 0)
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return 0;
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rb = kmalloc(sizeof(*rb) + len, GFP_KERNEL);
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if (rb == NULL)
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return -ENOMEM;
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rb->cons = 0;
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rb->len = len;
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memcpy(rb->msg, data, len);
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list_add_tail(&rb->list, queue);
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return 0;
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}
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/*
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* Free all the read_buffer s on a list.
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* Caller must have sole reference to list.
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*/
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static void queue_cleanup(struct list_head *list)
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{
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struct read_buffer *rb;
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while (!list_empty(list)) {
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rb = list_entry(list->next, struct read_buffer, list);
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list_del(list->next);
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kfree(rb);
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}
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}
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struct watch_adapter {
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struct list_head list;
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struct xenbus_watch watch;
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struct xenbus_file_priv *dev_data;
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char *token;
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};
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static void free_watch_adapter(struct watch_adapter *watch)
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{
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kfree(watch->watch.node);
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kfree(watch->token);
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kfree(watch);
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}
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static struct watch_adapter *alloc_watch_adapter(const char *path,
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const char *token)
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{
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struct watch_adapter *watch;
|
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|
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watch = kzalloc(sizeof(*watch), GFP_KERNEL);
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if (watch == NULL)
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goto out_fail;
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watch->watch.node = kstrdup(path, GFP_KERNEL);
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if (watch->watch.node == NULL)
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goto out_free;
|
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|
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watch->token = kstrdup(token, GFP_KERNEL);
|
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if (watch->token == NULL)
|
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goto out_free;
|
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|
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return watch;
|
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|
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out_free:
|
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free_watch_adapter(watch);
|
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|
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out_fail:
|
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return NULL;
|
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}
|
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|
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static void watch_fired(struct xenbus_watch *watch,
|
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const char **vec,
|
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unsigned int len)
|
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{
|
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struct watch_adapter *adap;
|
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struct xsd_sockmsg hdr;
|
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const char *path, *token;
|
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int path_len, tok_len, body_len, data_len = 0;
|
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int ret;
|
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LIST_HEAD(staging_q);
|
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|
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adap = container_of(watch, struct watch_adapter, watch);
|
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|
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path = vec[XS_WATCH_PATH];
|
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token = adap->token;
|
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|
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path_len = strlen(path) + 1;
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tok_len = strlen(token) + 1;
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if (len > 2)
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data_len = vec[len] - vec[2] + 1;
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body_len = path_len + tok_len + data_len;
|
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|
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hdr.type = XS_WATCH_EVENT;
|
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hdr.len = body_len;
|
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|
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mutex_lock(&adap->dev_data->reply_mutex);
|
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|
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ret = queue_reply(&staging_q, &hdr, sizeof(hdr));
|
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if (!ret)
|
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ret = queue_reply(&staging_q, path, path_len);
|
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if (!ret)
|
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ret = queue_reply(&staging_q, token, tok_len);
|
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if (!ret && len > 2)
|
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ret = queue_reply(&staging_q, vec[2], data_len);
|
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|
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if (!ret) {
|
||||
/* success: pass reply list onto watcher */
|
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list_splice_tail(&staging_q, &adap->dev_data->read_buffers);
|
||||
wake_up(&adap->dev_data->read_waitq);
|
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} else
|
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queue_cleanup(&staging_q);
|
||||
|
||||
mutex_unlock(&adap->dev_data->reply_mutex);
|
||||
}
|
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|
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static int xenbus_write_transaction(unsigned msg_type,
|
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struct xenbus_file_priv *u)
|
||||
{
|
||||
int rc, ret;
|
||||
void *reply;
|
||||
struct xenbus_transaction_holder *trans = NULL;
|
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LIST_HEAD(staging_q);
|
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|
||||
if (msg_type == XS_TRANSACTION_START) {
|
||||
trans = kmalloc(sizeof(*trans), GFP_KERNEL);
|
||||
if (!trans) {
|
||||
rc = -ENOMEM;
|
||||
goto out;
|
||||
}
|
||||
}
|
||||
|
||||
reply = xenbus_dev_request_and_reply(&u->u.msg);
|
||||
if (IS_ERR(reply)) {
|
||||
kfree(trans);
|
||||
rc = PTR_ERR(reply);
|
||||
goto out;
|
||||
}
|
||||
|
||||
if (msg_type == XS_TRANSACTION_START) {
|
||||
trans->handle.id = simple_strtoul(reply, NULL, 0);
|
||||
|
||||
list_add(&trans->list, &u->transactions);
|
||||
} else if (msg_type == XS_TRANSACTION_END) {
|
||||
list_for_each_entry(trans, &u->transactions, list)
|
||||
if (trans->handle.id == u->u.msg.tx_id)
|
||||
break;
|
||||
BUG_ON(&trans->list == &u->transactions);
|
||||
list_del(&trans->list);
|
||||
|
||||
kfree(trans);
|
||||
}
|
||||
|
||||
mutex_lock(&u->reply_mutex);
|
||||
ret = queue_reply(&staging_q, &u->u.msg, sizeof(u->u.msg));
|
||||
if (!ret)
|
||||
ret = queue_reply(&staging_q, reply, u->u.msg.len);
|
||||
if (!ret) {
|
||||
list_splice_tail(&staging_q, &u->read_buffers);
|
||||
wake_up(&u->read_waitq);
|
||||
} else {
|
||||
queue_cleanup(&staging_q);
|
||||
rc = ret;
|
||||
}
|
||||
mutex_unlock(&u->reply_mutex);
|
||||
|
||||
kfree(reply);
|
||||
|
||||
out:
|
||||
return rc;
|
||||
}
|
||||
|
||||
static int xenbus_write_watch(unsigned msg_type, struct xenbus_file_priv *u)
|
||||
{
|
||||
struct watch_adapter *watch, *tmp_watch;
|
||||
char *path, *token;
|
||||
int err, rc;
|
||||
LIST_HEAD(staging_q);
|
||||
|
||||
path = u->u.buffer + sizeof(u->u.msg);
|
||||
token = memchr(path, 0, u->u.msg.len);
|
||||
if (token == NULL) {
|
||||
rc = -EILSEQ;
|
||||
goto out;
|
||||
}
|
||||
token++;
|
||||
|
||||
if (msg_type == XS_WATCH) {
|
||||
watch = alloc_watch_adapter(path, token);
|
||||
if (watch == NULL) {
|
||||
rc = -ENOMEM;
|
||||
goto out;
|
||||
}
|
||||
|
||||
watch->watch.callback = watch_fired;
|
||||
watch->dev_data = u;
|
||||
|
||||
err = register_xenbus_watch(&watch->watch);
|
||||
if (err) {
|
||||
free_watch_adapter(watch);
|
||||
rc = err;
|
||||
goto out;
|
||||
}
|
||||
list_add(&watch->list, &u->watches);
|
||||
} else {
|
||||
list_for_each_entry_safe(watch, tmp_watch, &u->watches, list) {
|
||||
if (!strcmp(watch->token, token) &&
|
||||
!strcmp(watch->watch.node, path)) {
|
||||
unregister_xenbus_watch(&watch->watch);
|
||||
list_del(&watch->list);
|
||||
free_watch_adapter(watch);
|
||||
break;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/* Success. Synthesize a reply to say all is OK. */
|
||||
{
|
||||
struct {
|
||||
struct xsd_sockmsg hdr;
|
||||
char body[3];
|
||||
} __packed reply = {
|
||||
{
|
||||
.type = msg_type,
|
||||
.len = sizeof(reply.body)
|
||||
},
|
||||
"OK"
|
||||
};
|
||||
|
||||
mutex_lock(&u->reply_mutex);
|
||||
rc = queue_reply(&u->read_buffers, &reply, sizeof(reply));
|
||||
mutex_unlock(&u->reply_mutex);
|
||||
}
|
||||
|
||||
out:
|
||||
return rc;
|
||||
}
|
||||
|
||||
static ssize_t xenbus_file_write(struct file *filp,
|
||||
const char __user *ubuf,
|
||||
size_t len, loff_t *ppos)
|
||||
{
|
||||
struct xenbus_file_priv *u = filp->private_data;
|
||||
uint32_t msg_type;
|
||||
int rc = len;
|
||||
int ret;
|
||||
LIST_HEAD(staging_q);
|
||||
|
||||
/*
|
||||
* We're expecting usermode to be writing properly formed
|
||||
* xenbus messages. If they write an incomplete message we
|
||||
* buffer it up. Once it is complete, we act on it.
|
||||
*/
|
||||
|
||||
/*
|
||||
* Make sure concurrent writers can't stomp all over each
|
||||
* other's messages and make a mess of our partial message
|
||||
* buffer. We don't make any attemppt to stop multiple
|
||||
* writers from making a mess of each other's incomplete
|
||||
* messages; we're just trying to guarantee our own internal
|
||||
* consistency and make sure that single writes are handled
|
||||
* atomically.
|
||||
*/
|
||||
mutex_lock(&u->msgbuffer_mutex);
|
||||
|
||||
/* Get this out of the way early to avoid confusion */
|
||||
if (len == 0)
|
||||
goto out;
|
||||
|
||||
/* Can't write a xenbus message larger we can buffer */
|
||||
if ((len + u->len) > sizeof(u->u.buffer)) {
|
||||
/* On error, dump existing buffer */
|
||||
u->len = 0;
|
||||
rc = -EINVAL;
|
||||
goto out;
|
||||
}
|
||||
|
||||
ret = copy_from_user(u->u.buffer + u->len, ubuf, len);
|
||||
|
||||
if (ret == len) {
|
||||
rc = -EFAULT;
|
||||
goto out;
|
||||
}
|
||||
|
||||
/* Deal with a partial copy. */
|
||||
len -= ret;
|
||||
rc = len;
|
||||
|
||||
u->len += len;
|
||||
|
||||
/* Return if we haven't got a full message yet */
|
||||
if (u->len < sizeof(u->u.msg))
|
||||
goto out; /* not even the header yet */
|
||||
|
||||
/* If we're expecting a message that's larger than we can
|
||||
possibly send, dump what we have and return an error. */
|
||||
if ((sizeof(u->u.msg) + u->u.msg.len) > sizeof(u->u.buffer)) {
|
||||
rc = -E2BIG;
|
||||
u->len = 0;
|
||||
goto out;
|
||||
}
|
||||
|
||||
if (u->len < (sizeof(u->u.msg) + u->u.msg.len))
|
||||
goto out; /* incomplete data portion */
|
||||
|
||||
/*
|
||||
* OK, now we have a complete message. Do something with it.
|
||||
*/
|
||||
|
||||
msg_type = u->u.msg.type;
|
||||
|
||||
switch (msg_type) {
|
||||
case XS_TRANSACTION_START:
|
||||
case XS_TRANSACTION_END:
|
||||
case XS_DIRECTORY:
|
||||
case XS_READ:
|
||||
case XS_GET_PERMS:
|
||||
case XS_RELEASE:
|
||||
case XS_GET_DOMAIN_PATH:
|
||||
case XS_WRITE:
|
||||
case XS_MKDIR:
|
||||
case XS_RM:
|
||||
case XS_SET_PERMS:
|
||||
/* Send out a transaction */
|
||||
ret = xenbus_write_transaction(msg_type, u);
|
||||
break;
|
||||
|
||||
case XS_WATCH:
|
||||
case XS_UNWATCH:
|
||||
/* (Un)Ask for some path to be watched for changes */
|
||||
ret = xenbus_write_watch(msg_type, u);
|
||||
break;
|
||||
|
||||
default:
|
||||
ret = -EINVAL;
|
||||
break;
|
||||
}
|
||||
if (ret != 0)
|
||||
rc = ret;
|
||||
|
||||
/* Buffered message consumed */
|
||||
u->len = 0;
|
||||
|
||||
out:
|
||||
mutex_unlock(&u->msgbuffer_mutex);
|
||||
return rc;
|
||||
}
|
||||
|
||||
static int xenbus_file_open(struct inode *inode, struct file *filp)
|
||||
{
|
||||
struct xenbus_file_priv *u;
|
||||
|
||||
if (xen_store_evtchn == 0)
|
||||
return -ENOENT;
|
||||
|
||||
nonseekable_open(inode, filp);
|
||||
|
||||
u = kzalloc(sizeof(*u), GFP_KERNEL);
|
||||
if (u == NULL)
|
||||
return -ENOMEM;
|
||||
|
||||
INIT_LIST_HEAD(&u->transactions);
|
||||
INIT_LIST_HEAD(&u->watches);
|
||||
INIT_LIST_HEAD(&u->read_buffers);
|
||||
init_waitqueue_head(&u->read_waitq);
|
||||
|
||||
mutex_init(&u->reply_mutex);
|
||||
mutex_init(&u->msgbuffer_mutex);
|
||||
|
||||
filp->private_data = u;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int xenbus_file_release(struct inode *inode, struct file *filp)
|
||||
{
|
||||
struct xenbus_file_priv *u = filp->private_data;
|
||||
struct xenbus_transaction_holder *trans, *tmp;
|
||||
struct watch_adapter *watch, *tmp_watch;
|
||||
|
||||
/*
|
||||
* No need for locking here because there are no other users,
|
||||
* by definition.
|
||||
*/
|
||||
|
||||
list_for_each_entry_safe(trans, tmp, &u->transactions, list) {
|
||||
xenbus_transaction_end(trans->handle, 1);
|
||||
list_del(&trans->list);
|
||||
kfree(trans);
|
||||
}
|
||||
|
||||
list_for_each_entry_safe(watch, tmp_watch, &u->watches, list) {
|
||||
unregister_xenbus_watch(&watch->watch);
|
||||
list_del(&watch->list);
|
||||
free_watch_adapter(watch);
|
||||
}
|
||||
|
||||
kfree(u);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static unsigned int xenbus_file_poll(struct file *file, poll_table *wait)
|
||||
{
|
||||
struct xenbus_file_priv *u = file->private_data;
|
||||
|
||||
poll_wait(file, &u->read_waitq, wait);
|
||||
if (!list_empty(&u->read_buffers))
|
||||
return POLLIN | POLLRDNORM;
|
||||
return 0;
|
||||
}
|
||||
|
||||
const struct file_operations xenbus_file_ops = {
|
||||
.read = xenbus_file_read,
|
||||
.write = xenbus_file_write,
|
||||
.open = xenbus_file_open,
|
||||
.release = xenbus_file_release,
|
||||
.poll = xenbus_file_poll,
|
||||
};
|
6
drivers/xen/xenfs/xenfs.h
Normal file
6
drivers/xen/xenfs/xenfs.h
Normal file
|
@ -0,0 +1,6 @@
|
|||
#ifndef _XENFS_XENBUS_H
|
||||
#define _XENFS_XENBUS_H
|
||||
|
||||
extern const struct file_operations xenbus_file_ops;
|
||||
|
||||
#endif /* _XENFS_XENBUS_H */
|
|
@ -13,6 +13,7 @@
|
|||
#define EFS_SUPER_MAGIC 0x414A53
|
||||
#define EXT2_SUPER_MAGIC 0xEF53
|
||||
#define EXT3_SUPER_MAGIC 0xEF53
|
||||
#define XENFS_SUPER_MAGIC 0xabba1974
|
||||
#define EXT4_SUPER_MAGIC 0xEF53
|
||||
#define HPFS_SUPER_MAGIC 0xf995e849
|
||||
#define ISOFS_SUPER_MAGIC 0x9660
|
||||
|
|
|
@ -136,8 +136,6 @@ struct xenbus_transaction
|
|||
/* Nil transaction ID. */
|
||||
#define XBT_NIL ((struct xenbus_transaction) { 0 })
|
||||
|
||||
int __init xenbus_dev_init(void);
|
||||
|
||||
char **xenbus_directory(struct xenbus_transaction t,
|
||||
const char *dir, const char *node, unsigned int *num);
|
||||
void *xenbus_read(struct xenbus_transaction t,
|
||||
|
|
Loading…
Reference in New Issue
Block a user