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-rw-r--r--drivers/xen/xenbus/Makefile2
-rw-r--r--drivers/xen/xenbus/xenbus_client.c193
-rw-r--r--drivers/xen/xenbus/xenbus_comms.h4
-rw-r--r--drivers/xen/xenbus/xenbus_dev_backend.c90
-rw-r--r--drivers/xen/xenbus/xenbus_dev_frontend.c625
-rw-r--r--drivers/xen/xenbus/xenbus_probe.c9
-rw-r--r--drivers/xen/xenbus/xenbus_probe.h6
-rw-r--r--drivers/xen/xenbus/xenbus_probe_backend.c8
-rw-r--r--drivers/xen/xenbus/xenbus_probe_frontend.c8
-rw-r--r--drivers/xen/xenbus/xenbus_xs.c23
10 files changed, 908 insertions, 60 deletions
diff --git a/drivers/xen/xenbus/Makefile b/drivers/xen/xenbus/Makefile
index 8dca685358b4..31e2e9050c7a 100644
--- a/drivers/xen/xenbus/Makefile
+++ b/drivers/xen/xenbus/Makefile
@@ -1,4 +1,5 @@
obj-y += xenbus.o
+obj-y += xenbus_dev_frontend.o
xenbus-objs =
xenbus-objs += xenbus_client.o
@@ -9,4 +10,5 @@ xenbus-objs += xenbus_probe.o
xenbus-be-objs-$(CONFIG_XEN_BACKEND) += xenbus_probe_backend.o
xenbus-objs += $(xenbus-be-objs-y)
+obj-$(CONFIG_XEN_BACKEND) += xenbus_dev_backend.o
obj-$(CONFIG_XEN_XENBUS_FRONTEND) += xenbus_probe_frontend.o
diff --git a/drivers/xen/xenbus/xenbus_client.c b/drivers/xen/xenbus/xenbus_client.c
index 1906125eab49..566d2adbd6ea 100644
--- a/drivers/xen/xenbus/xenbus_client.c
+++ b/drivers/xen/xenbus/xenbus_client.c
@@ -32,15 +32,39 @@
#include <linux/slab.h>
#include <linux/types.h>
+#include <linux/spinlock.h>
#include <linux/vmalloc.h>
#include <linux/export.h>
#include <asm/xen/hypervisor.h>
#include <asm/xen/page.h>
#include <xen/interface/xen.h>
#include <xen/interface/event_channel.h>
+#include <xen/balloon.h>
#include <xen/events.h>
#include <xen/grant_table.h>
#include <xen/xenbus.h>
+#include <xen/xen.h>
+
+#include "xenbus_probe.h"
+
+struct xenbus_map_node {
+ struct list_head next;
+ union {
+ struct vm_struct *area; /* PV */
+ struct page *page; /* HVM */
+ };
+ grant_handle_t handle;
+};
+
+static DEFINE_SPINLOCK(xenbus_valloc_lock);
+static LIST_HEAD(xenbus_valloc_pages);
+
+struct xenbus_ring_ops {
+ int (*map)(struct xenbus_device *dev, int gnt, void **vaddr);
+ int (*unmap)(struct xenbus_device *dev, void *vaddr);
+};
+
+static const struct xenbus_ring_ops *ring_ops __read_mostly;
const char *xenbus_strstate(enum xenbus_state state)
{
@@ -436,19 +460,33 @@ EXPORT_SYMBOL_GPL(xenbus_free_evtchn);
*/
int xenbus_map_ring_valloc(struct xenbus_device *dev, int gnt_ref, void **vaddr)
{
+ return ring_ops->map(dev, gnt_ref, vaddr);
+}
+EXPORT_SYMBOL_GPL(xenbus_map_ring_valloc);
+
+static int xenbus_map_ring_valloc_pv(struct xenbus_device *dev,
+ int gnt_ref, void **vaddr)
+{
struct gnttab_map_grant_ref op = {
.flags = GNTMAP_host_map | GNTMAP_contains_pte,
.ref = gnt_ref,
.dom = dev->otherend_id,
};
+ struct xenbus_map_node *node;
struct vm_struct *area;
pte_t *pte;
*vaddr = NULL;
+ node = kzalloc(sizeof(*node), GFP_KERNEL);
+ if (!node)
+ return -ENOMEM;
+
area = alloc_vm_area(PAGE_SIZE, &pte);
- if (!area)
+ if (!area) {
+ kfree(node);
return -ENOMEM;
+ }
op.host_addr = arbitrary_virt_to_machine(pte).maddr;
@@ -457,19 +495,59 @@ int xenbus_map_ring_valloc(struct xenbus_device *dev, int gnt_ref, void **vaddr)
if (op.status != GNTST_okay) {
free_vm_area(area);
+ kfree(node);
xenbus_dev_fatal(dev, op.status,
"mapping in shared page %d from domain %d",
gnt_ref, dev->otherend_id);
return op.status;
}
- /* Stuff the handle in an unused field */
- area->phys_addr = (unsigned long)op.handle;
+ node->handle = op.handle;
+ node->area = area;
+
+ spin_lock(&xenbus_valloc_lock);
+ list_add(&node->next, &xenbus_valloc_pages);
+ spin_unlock(&xenbus_valloc_lock);
*vaddr = area->addr;
return 0;
}
-EXPORT_SYMBOL_GPL(xenbus_map_ring_valloc);
+
+static int xenbus_map_ring_valloc_hvm(struct xenbus_device *dev,
+ int gnt_ref, void **vaddr)
+{
+ struct xenbus_map_node *node;
+ int err;
+ void *addr;
+
+ *vaddr = NULL;
+
+ node = kzalloc(sizeof(*node), GFP_KERNEL);
+ if (!node)
+ return -ENOMEM;
+
+ err = alloc_xenballooned_pages(1, &node->page, false /* lowmem */);
+ if (err)
+ goto out_err;
+
+ addr = pfn_to_kaddr(page_to_pfn(node->page));
+
+ err = xenbus_map_ring(dev, gnt_ref, &node->handle, addr);
+ if (err)
+ goto out_err;
+
+ spin_lock(&xenbus_valloc_lock);
+ list_add(&node->next, &xenbus_valloc_pages);
+ spin_unlock(&xenbus_valloc_lock);
+
+ *vaddr = addr;
+ return 0;
+
+ out_err:
+ free_xenballooned_pages(1, &node->page);
+ kfree(node);
+ return err;
+}
/**
@@ -489,12 +567,10 @@ EXPORT_SYMBOL_GPL(xenbus_map_ring_valloc);
int xenbus_map_ring(struct xenbus_device *dev, int gnt_ref,
grant_handle_t *handle, void *vaddr)
{
- struct gnttab_map_grant_ref op = {
- .host_addr = (unsigned long)vaddr,
- .flags = GNTMAP_host_map,
- .ref = gnt_ref,
- .dom = dev->otherend_id,
- };
+ struct gnttab_map_grant_ref op;
+
+ gnttab_set_map_op(&op, (phys_addr_t)vaddr, GNTMAP_host_map, gnt_ref,
+ dev->otherend_id);
if (HYPERVISOR_grant_table_op(GNTTABOP_map_grant_ref, &op, 1))
BUG();
@@ -525,32 +601,36 @@ EXPORT_SYMBOL_GPL(xenbus_map_ring);
*/
int xenbus_unmap_ring_vfree(struct xenbus_device *dev, void *vaddr)
{
- struct vm_struct *area;
+ return ring_ops->unmap(dev, vaddr);
+}
+EXPORT_SYMBOL_GPL(xenbus_unmap_ring_vfree);
+
+static int xenbus_unmap_ring_vfree_pv(struct xenbus_device *dev, void *vaddr)
+{
+ struct xenbus_map_node *node;
struct gnttab_unmap_grant_ref op = {
.host_addr = (unsigned long)vaddr,
};
unsigned int level;
- /* It'd be nice if linux/vmalloc.h provided a find_vm_area(void *addr)
- * method so that we don't have to muck with vmalloc internals here.
- * We could force the user to hang on to their struct vm_struct from
- * xenbus_map_ring_valloc, but these 6 lines considerably simplify
- * this API.
- */
- read_lock(&vmlist_lock);
- for (area = vmlist; area != NULL; area = area->next) {
- if (area->addr == vaddr)
- break;
+ spin_lock(&xenbus_valloc_lock);
+ list_for_each_entry(node, &xenbus_valloc_pages, next) {
+ if (node->area->addr == vaddr) {
+ list_del(&node->next);
+ goto found;
+ }
}
- read_unlock(&vmlist_lock);
+ node = NULL;
+ found:
+ spin_unlock(&xenbus_valloc_lock);
- if (!area) {
+ if (!node) {
xenbus_dev_error(dev, -ENOENT,
"can't find mapped virtual address %p", vaddr);
return GNTST_bad_virt_addr;
}
- op.handle = (grant_handle_t)area->phys_addr;
+ op.handle = node->handle;
op.host_addr = arbitrary_virt_to_machine(
lookup_address((unsigned long)vaddr, &level)).maddr;
@@ -558,16 +638,50 @@ int xenbus_unmap_ring_vfree(struct xenbus_device *dev, void *vaddr)
BUG();
if (op.status == GNTST_okay)
- free_vm_area(area);
+ free_vm_area(node->area);
else
xenbus_dev_error(dev, op.status,
"unmapping page at handle %d error %d",
- (int16_t)area->phys_addr, op.status);
+ node->handle, op.status);
+ kfree(node);
return op.status;
}
-EXPORT_SYMBOL_GPL(xenbus_unmap_ring_vfree);
+static int xenbus_unmap_ring_vfree_hvm(struct xenbus_device *dev, void *vaddr)
+{
+ int rv;
+ struct xenbus_map_node *node;
+ void *addr;
+
+ spin_lock(&xenbus_valloc_lock);
+ list_for_each_entry(node, &xenbus_valloc_pages, next) {
+ addr = pfn_to_kaddr(page_to_pfn(node->page));
+ if (addr == vaddr) {
+ list_del(&node->next);
+ goto found;
+ }
+ }
+ node = NULL;
+ found:
+ spin_unlock(&xenbus_valloc_lock);
+
+ if (!node) {
+ xenbus_dev_error(dev, -ENOENT,
+ "can't find mapped virtual address %p", vaddr);
+ return GNTST_bad_virt_addr;
+ }
+
+ rv = xenbus_unmap_ring(dev, node->handle, addr);
+
+ if (!rv)
+ free_xenballooned_pages(1, &node->page);
+ else
+ WARN(1, "Leaking %p\n", vaddr);
+
+ kfree(node);
+ return rv;
+}
/**
* xenbus_unmap_ring
@@ -582,10 +696,9 @@ EXPORT_SYMBOL_GPL(xenbus_unmap_ring_vfree);
int xenbus_unmap_ring(struct xenbus_device *dev,
grant_handle_t handle, void *vaddr)
{
- struct gnttab_unmap_grant_ref op = {
- .host_addr = (unsigned long)vaddr,
- .handle = handle,
- };
+ struct gnttab_unmap_grant_ref op;
+
+ gnttab_set_unmap_op(&op, (phys_addr_t)vaddr, GNTMAP_host_map, handle);
if (HYPERVISOR_grant_table_op(GNTTABOP_unmap_grant_ref, &op, 1))
BUG();
@@ -617,3 +730,21 @@ enum xenbus_state xenbus_read_driver_state(const char *path)
return result;
}
EXPORT_SYMBOL_GPL(xenbus_read_driver_state);
+
+static const struct xenbus_ring_ops ring_ops_pv = {
+ .map = xenbus_map_ring_valloc_pv,
+ .unmap = xenbus_unmap_ring_vfree_pv,
+};
+
+static const struct xenbus_ring_ops ring_ops_hvm = {
+ .map = xenbus_map_ring_valloc_hvm,
+ .unmap = xenbus_unmap_ring_vfree_hvm,
+};
+
+void __init xenbus_ring_ops_init(void)
+{
+ if (xen_pv_domain())
+ ring_ops = &ring_ops_pv;
+ else
+ ring_ops = &ring_ops_hvm;
+}
diff --git a/drivers/xen/xenbus/xenbus_comms.h b/drivers/xen/xenbus/xenbus_comms.h
index c21db7513736..6e42800fa499 100644
--- a/drivers/xen/xenbus/xenbus_comms.h
+++ b/drivers/xen/xenbus/xenbus_comms.h
@@ -31,6 +31,8 @@
#ifndef _XENBUS_COMMS_H
#define _XENBUS_COMMS_H
+#include <linux/fs.h>
+
int xs_init(void);
int xb_init_comms(void);
@@ -43,4 +45,6 @@ int xs_input_avail(void);
extern struct xenstore_domain_interface *xen_store_interface;
extern int xen_store_evtchn;
+extern const struct file_operations xen_xenbus_fops;
+
#endif /* _XENBUS_COMMS_H */
diff --git a/drivers/xen/xenbus/xenbus_dev_backend.c b/drivers/xen/xenbus/xenbus_dev_backend.c
new file mode 100644
index 000000000000..3d3be78c1093
--- /dev/null
+++ b/drivers/xen/xenbus/xenbus_dev_backend.c
@@ -0,0 +1,90 @@
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/mm.h>
+#include <linux/fs.h>
+#include <linux/miscdevice.h>
+#include <linux/module.h>
+#include <linux/capability.h>
+
+#include <xen/xen.h>
+#include <xen/page.h>
+#include <xen/xenbus_dev.h>
+
+#include "xenbus_comms.h"
+
+MODULE_LICENSE("GPL");
+
+static int xenbus_backend_open(struct inode *inode, struct file *filp)
+{
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ return nonseekable_open(inode, filp);
+}
+
+static long xenbus_backend_ioctl(struct file *file, unsigned int cmd, unsigned long data)
+{
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ switch (cmd) {
+ case IOCTL_XENBUS_BACKEND_EVTCHN:
+ if (xen_store_evtchn > 0)
+ return xen_store_evtchn;
+ return -ENODEV;
+
+ default:
+ return -ENOTTY;
+ }
+}
+
+static int xenbus_backend_mmap(struct file *file, struct vm_area_struct *vma)
+{
+ size_t size = vma->vm_end - vma->vm_start;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ 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 xenbus_backend_fops = {
+ .open = xenbus_backend_open,
+ .mmap = xenbus_backend_mmap,
+ .unlocked_ioctl = xenbus_backend_ioctl,
+};
+
+static struct miscdevice xenbus_backend_dev = {
+ .minor = MISC_DYNAMIC_MINOR,
+ .name = "xen/xenbus_backend",
+ .fops = &xenbus_backend_fops,
+};
+
+static int __init xenbus_backend_init(void)
+{
+ int err;
+
+ if (!xen_initial_domain())
+ return -ENODEV;
+
+ err = misc_register(&xenbus_backend_dev);
+ if (err)
+ printk(KERN_ERR "Could not register xenbus backend device\n");
+ return err;
+}
+
+static void __exit xenbus_backend_exit(void)
+{
+ misc_deregister(&xenbus_backend_dev);
+}
+
+module_init(xenbus_backend_init);
+module_exit(xenbus_backend_exit);
diff --git a/drivers/xen/xenbus/xenbus_dev_frontend.c b/drivers/xen/xenbus/xenbus_dev_frontend.c
new file mode 100644
index 000000000000..527dc2a3b89f
--- /dev/null
+++ b/drivers/xen/xenbus/xenbus_dev_frontend.c
@@ -0,0 +1,625 @@
+/*
+ * Driver giving user-space access to the kernel's xenbus connection
+ * to xenstore.
+ *
+ * Copyright (c) 2005, Christian Limpach
+ * Copyright (c) 2005, Rusty Russell, IBM Corporation
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation; or, when distributed
+ * separately from the Linux kernel or incorporated into other
+ * software packages, subject to the following license:
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this source file (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy, modify,
+ * merge, publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ *
+ * Changes:
+ * 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/uio.h>
+#include <linux/notifier.h>
+#include <linux/wait.h>
+#include <linux/fs.h>
+#include <linux/poll.h>
+#include <linux/mutex.h>
+#include <linux/sched.h>
+#include <linux/spinlock.h>
+#include <linux/mount.h>
+#include <linux/pagemap.h>
+#include <linux/uaccess.h>
+#include <linux/init.h>
+#include <linux/namei.h>
+#include <linux/string.h>
+#include <linux/slab.h>
+#include <linux/miscdevice.h>
+#include <linux/module.h>
+
+#include "xenbus_comms.h"
+
+#include <xen/xenbus.h>
+#include <xen/xen.h>
+#include <asm/xen/hypervisor.h>
+
+MODULE_LICENSE("GPL");
+
+/*
+ * An element of a list of outstanding transactions, for which we're
+ * still waiting a reply.
+ */
+struct xenbus_transaction_holder {
+ struct list_head list;
+ struct xenbus_transaction handle;
+};
+
+/*
+ * A buffer of data on the queue.
+ */
+struct read_buffer {
+ struct list_head list;
+ unsigned int cons;
+ unsigned int len;
+ char msg[];
+};
+
+struct xenbus_file_priv {
+ /*
+ * msgbuffer_mutex is held while partial requests are built up
+ * and complete requests are acted on. It therefore protects
+ * the "transactions" and "watches" lists, and the partial
+ * request length and buffer.
+ *
+ * reply_mutex protects the reply being built up to return to
+ * usermode. It nests inside msgbuffer_mutex but may be held
+ * alone during a watch callback.
+ */
+ struct mutex msgbuffer_mutex;
+
+ /* In-progress transactions */
+ struct list_head transactions;
+
+ /* Active watches. */
+ struct list_head watches;
+
+ /* Partial request. */
+ unsigned int len;
+ union {
+ struct xsd_sockmsg msg;
+ char buffer[XENSTORE_PAYLOAD_MAX];
+ } u;
+
+ /* Response queue. */
+ struct mutex reply_mutex;
+ struct list_head read_buffers;
+ wait_queue_head_t read_waitq;
+
+};
+
+/* Read out any raw xenbus messages queued up. */
+static ssize_t xenbus_file_read(struct file *filp,
+ char __user *ubuf,
+ size_t len, loff_t *ppos)
+{
+ struct xenbus_file_priv *u = filp->private_data;
+ struct read_buffer *rb;
+ unsigned i;
+ int ret;
+
+ mutex_lock(&u->reply_mutex);
+again:
+ while (list_empty(&u->read_buffers)) {
+ mutex_unlock(&u->reply_mutex);
+ if (filp->f_flags & O_NONBLOCK)
+ return -EAGAIN;
+
+ ret = wait_event_interruptible(u->read_waitq,
+ !list_empty(&u->read_buffers));
+ if (ret)
+ return ret;
+ mutex_lock(&u->reply_mutex);
+ }
+
+ rb = list_entry(u->read_buffers.next, struct read_buffer, list);
+ i = 0;
+ while (i < len) {
+ unsigned sz = min((unsigned)len - i, rb->len - rb->cons);
+
+ ret = copy_to_user(ubuf + i, &rb->msg[rb->cons], sz);
+
+ i += sz - ret;
+ rb->cons += sz - ret;
+
+ if (ret != 0) {
+ if (i == 0)
+ i = -EFAULT;
+ goto out;
+ }
+
+ /* Clear out buffer if it has been consumed */
+ if (rb->cons == rb->len) {
+ list_del(&rb->list);
+ kfree(rb);
+ if (list_empty(&u->read_buffers))
+ break;
+ rb = list_entry(u->read_buffers.next,
+ struct read_buffer, list);
+ }
+ }
+ if (i == 0)
+ goto again;
+
+out:
+ mutex_unlock(&u->reply_mutex);
+ return i;
+}
+
+/*
+ * Add a buffer to the queue. Caller must hold the appropriate lock
+ * if the queue is not local. (Commonly the caller will build up
+ * multiple queued buffers on a temporary local list, and then add it
+ * to the appropriate list under lock once all the buffers have een
+ * successfully allocated.)
+ */
+static int queue_reply(struct list_head *queue, const void *data, size_t len)
+{
+ struct read_buffer *rb;
+
+ if (len == 0)
+ return 0;
+
+ rb = kmalloc(sizeof(*rb) + len, GFP_KERNEL);
+ if (rb == NULL)
+ return -ENOMEM;
+
+ rb->cons = 0;
+ rb->len = len;
+
+ memcpy(rb->msg, data, len);
+
+ list_add_tail(&rb->list, queue);
+ return 0;
+}
+
+/*
+ * Free all the read_buffer s on a list.
+ * Caller must have sole reference to list.
+ */
+static void queue_cleanup(struct list_head *list)
+{
+ struct read_buffer *rb;
+
+ while (!list_empty(list)) {
+ rb = list_entry(list->next, struct read_buffer, list);
+ list_del(list->next);
+ kfree(rb);
+ }
+}
+
+struct watch_adapter {
+ struct list_head list;
+ struct xenbus_watch watch;
+ struct xenbus_file_priv *dev_data;
+ char *token;
+};
+
+static void free_watch_adapter(struct watch_adapter *watch)
+{
+ kfree(watch->watch.node);
+ kfree(watch->token);
+ kfree(watch);
+}
+
+static struct watch_adapter *alloc_watch_adapter(const char *path,
+ const char *token)
+{
+ struct watch_adapter *watch;
+
+ watch = kzalloc(sizeof(*watch), GFP_KERNEL);
+ if (watch == NULL)
+ goto out_fail;
+
+ watch->watch.node = kstrdup(path, GFP_KERNEL);
+ if (watch->watch.node == NULL)
+ goto out_free;
+
+ watch->token = kstrdup(token, GFP_KERNEL);
+ if (watch->token == NULL)
+ goto out_free;
+
+ return watch;
+
+out_free:
+ free_watch_adapter(watch);
+
+out_fail:
+ return NULL;
+}
+
+static void watch_fired(struct xenbus_watch *watch,
+ const char **vec,
+ unsigned int len)
+{
+ struct watch_adapter *adap;
+ struct xsd_sockmsg hdr;
+ const char *path, *token;
+ int path_len, tok_len, body_len, data_len = 0;
+ int ret;
+ LIST_HEAD(staging_q);
+
+ adap = container_of(watch, struct watch_adapter, watch);
+
+ path = vec[XS_WATCH_PATH];
+ token = adap->token;
+
+ path_len = strlen(path) + 1;
+ tok_len = strlen(token) + 1;
+ if (len > 2)
+ data_len = vec[len] - vec[2] + 1;
+ body_len = path_len + tok_len + data_len;
+
+ hdr.type = XS_WATCH_EVENT;
+ hdr.len = body_len;
+
+ mutex_lock(&adap->dev_data->reply_mutex);
+
+ ret = queue_reply(&staging_q, &hdr, sizeof(hdr));
+ if (!ret)
+ ret = queue_reply(&staging_q, path, path_len);
+ if (!ret)
+ ret = queue_reply(&staging_q, token, tok_len);
+ if (!ret && len > 2)
+ ret = queue_reply(&staging_q, vec[2], data_len);
+
+ if (!ret) {
+ /* success: pass reply list onto watcher */
+ list_splice_tail(&staging_q, &adap->dev_data->read_buffers);
+ wake_up(&adap->dev_data->read_waitq);
+ } else
+ queue_cleanup(&staging_q);
+
+ mutex_unlock(&adap->dev_data->reply_mutex);
+}
+
+static int xenbus_write_transaction(unsigned msg_type,
+ struct xenbus_file_priv *u)
+{
+ int rc;
+ void *reply;
+ struct xenbus_transaction_holder *trans = NULL;
+ LIST_HEAD(staging_q);
+
+ 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);
+ rc = queue_reply(&staging_q, &u->u.msg, sizeof(u->u.msg));
+ if (!rc)
+ rc = queue_reply(&staging_q, reply, u->u.msg.len);
+ if (!rc) {
+ list_splice_tail(&staging_q, &u->read_buffers);
+ wake_up(&u->read_waitq);
+ } else {
+ queue_cleanup(&staging_q);
+ }
+ 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));
+ wake_up(&u->read_waitq);
+ 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 != 0) {
+ 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_WATCH:
+ case XS_UNWATCH:
+ /* (Un)Ask for some path to be watched for changes */
+ ret = xenbus_write_watch(msg_type, u);
+ break;
+
+ default:
+ /* Send out a transaction */
+ ret = xenbus_write_transaction(msg_type, u);
+ 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;
+ struct read_buffer *rb, *tmp_rb;
+
+ /*
+ * 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);
+ }
+
+ list_for_each_entry_safe(rb, tmp_rb, &u->read_buffers, list) {
+ list_del(&rb->list);
+ kfree(rb);
+ }
+ 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 xen_xenbus_fops = {
+ .read = xenbus_file_read,
+ .write = xenbus_file_write,
+ .open = xenbus_file_open,
+ .release = xenbus_file_release,
+ .poll = xenbus_file_poll,
+ .llseek = no_llseek,
+};
+EXPORT_SYMBOL_GPL(xen_xenbus_fops);
+
+static struct miscdevice xenbus_dev = {
+ .minor = MISC_DYNAMIC_MINOR,
+ .name = "xen/xenbus",
+ .fops = &xen_xenbus_fops,
+};
+
+static int __init xenbus_init(void)
+{
+ int err;
+
+ if (!xen_domain())
+ return -ENODEV;
+
+ err = misc_register(&xenbus_dev);
+ if (err)
+ printk(KERN_ERR "Could not register xenbus frontend device\n");
+ return err;
+}
+
+static void __exit xenbus_exit(void)
+{
+ misc_deregister(&xenbus_dev);
+}
+
+module_init(xenbus_init);
+module_exit(xenbus_exit);
diff --git a/drivers/xen/xenbus/xenbus_probe.c b/drivers/xen/xenbus/xenbus_probe.c
index 1b178c6e8937..3864967202b5 100644
--- a/drivers/xen/xenbus/xenbus_probe.c
+++ b/drivers/xen/xenbus/xenbus_probe.c
@@ -291,14 +291,9 @@ void xenbus_dev_shutdown(struct device *_dev)
EXPORT_SYMBOL_GPL(xenbus_dev_shutdown);
int xenbus_register_driver_common(struct xenbus_driver *drv,
- struct xen_bus_type *bus,
- struct module *owner,
- const char *mod_name)
+ struct xen_bus_type *bus)
{
- drv->driver.name = drv->name;
drv->driver.bus = &bus->bus;
- drv->driver.owner = owner;
- drv->driver.mod_name = mod_name;
return driver_register(&drv->driver);
}
@@ -730,6 +725,8 @@ static int __init xenbus_init(void)
if (!xen_domain())
return -ENODEV;
+ xenbus_ring_ops_init();
+
if (xen_hvm_domain()) {
uint64_t v = 0;
err = hvm_get_parameter(HVM_PARAM_STORE_EVTCHN, &v);
diff --git a/drivers/xen/xenbus/xenbus_probe.h b/drivers/xen/xenbus/xenbus_probe.h
index 9b1de4e34c64..bb4f92ed8730 100644
--- a/drivers/xen/xenbus/xenbus_probe.h
+++ b/drivers/xen/xenbus/xenbus_probe.h
@@ -53,9 +53,7 @@ extern int xenbus_match(struct device *_dev, struct device_driver *_drv);
extern int xenbus_dev_probe(struct device *_dev);
extern int xenbus_dev_remove(struct device *_dev);
extern int xenbus_register_driver_common(struct xenbus_driver *drv,
- struct xen_bus_type *bus,
- struct module *owner,
- const char *mod_name);
+ struct xen_bus_type *bus);
extern int xenbus_probe_node(struct xen_bus_type *bus,
const char *type,
const char *nodename);
@@ -76,4 +74,6 @@ extern void xenbus_otherend_changed(struct xenbus_watch *watch,
extern int xenbus_read_otherend_details(struct xenbus_device *xendev,
char *id_node, char *path_node);
+void xenbus_ring_ops_init(void);
+
#endif
diff --git a/drivers/xen/xenbus/xenbus_probe_backend.c b/drivers/xen/xenbus/xenbus_probe_backend.c
index c3c7cd195c11..257be37d9091 100644
--- a/drivers/xen/xenbus/xenbus_probe_backend.c
+++ b/drivers/xen/xenbus/xenbus_probe_backend.c
@@ -232,15 +232,13 @@ int xenbus_dev_is_online(struct xenbus_device *dev)
}
EXPORT_SYMBOL_GPL(xenbus_dev_is_online);
-int __xenbus_register_backend(struct xenbus_driver *drv,
- struct module *owner, const char *mod_name)
+int xenbus_register_backend(struct xenbus_driver *drv)
{
drv->read_otherend_details = read_frontend_details;
- return xenbus_register_driver_common(drv, &xenbus_backend,
- owner, mod_name);
+ return xenbus_register_driver_common(drv, &xenbus_backend);
}
-EXPORT_SYMBOL_GPL(__xenbus_register_backend);
+EXPORT_SYMBOL_GPL(xenbus_register_backend);
static int backend_probe_and_watch(struct notifier_block *notifier,
unsigned long event,
diff --git a/drivers/xen/xenbus/xenbus_probe_frontend.c b/drivers/xen/xenbus/xenbus_probe_frontend.c
index 2f73195512b4..9c57819df51a 100644
--- a/drivers/xen/xenbus/xenbus_probe_frontend.c
+++ b/drivers/xen/xenbus/xenbus_probe_frontend.c
@@ -230,15 +230,13 @@ static void wait_for_devices(struct xenbus_driver *xendrv)
print_device_status);
}
-int __xenbus_register_frontend(struct xenbus_driver *drv,
- struct module *owner, const char *mod_name)
+int xenbus_register_frontend(struct xenbus_driver *drv)
{
int ret;
drv->read_otherend_details = read_backend_details;
- ret = xenbus_register_driver_common(drv, &xenbus_frontend,
- owner, mod_name);
+ ret = xenbus_register_driver_common(drv, &xenbus_frontend);
if (ret)
return ret;
@@ -247,7 +245,7 @@ int __xenbus_register_frontend(struct xenbus_driver *drv,
return 0;
}
-EXPORT_SYMBOL_GPL(__xenbus_register_frontend);
+EXPORT_SYMBOL_GPL(xenbus_register_frontend);
static DECLARE_WAIT_QUEUE_HEAD(backend_state_wq);
static int backend_state;
diff --git a/drivers/xen/xenbus/xenbus_xs.c b/drivers/xen/xenbus/xenbus_xs.c
index ede860f921df..d1c217b23a42 100644
--- a/drivers/xen/xenbus/xenbus_xs.c
+++ b/drivers/xen/xenbus/xenbus_xs.c
@@ -532,21 +532,18 @@ int xenbus_printf(struct xenbus_transaction t,
{
va_list ap;
int ret;
-#define PRINTF_BUFFER_SIZE 4096
- char *printf_buffer;
-
- printf_buffer = kmalloc(PRINTF_BUFFER_SIZE, GFP_NOIO | __GFP_HIGH);
- if (printf_buffer == NULL)
- return -ENOMEM;
+ char *buf;
va_start(ap, fmt);
- ret = vsnprintf(printf_buffer, PRINTF_BUFFER_SIZE, fmt, ap);
+ buf = kvasprintf(GFP_NOIO | __GFP_HIGH, fmt, ap);
va_end(ap);
- BUG_ON(ret > PRINTF_BUFFER_SIZE-1);
- ret = xenbus_write(t, dir, node, printf_buffer);
+ if (!buf)
+ return -ENOMEM;
+
+ ret = xenbus_write(t, dir, node, buf);
- kfree(printf_buffer);
+ kfree(buf);
return ret;
}
@@ -801,6 +798,12 @@ static int process_msg(void)
goto out;
}
+ if (msg->hdr.len > XENSTORE_PAYLOAD_MAX) {
+ kfree(msg);
+ err = -EINVAL;
+ goto out;
+ }
+
body = kmalloc(msg->hdr.len + 1, GFP_NOIO | __GFP_HIGH);
if (body == NULL) {
kfree(msg);
generated by cgit v1.2.3 (git 2.0.4) at 2024-11-08 21:24:34 +0000