4 * Driver giving user-space access to the kernel's xenbus connection
7 * Copyright (c) 2005, Christian Limpach
8 * Copyright (c) 2005, Rusty Russell, IBM Corporation
10 * This file may be distributed separately from the Linux kernel, or
11 * incorporated into other software packages, subject to the following license:
13 * Permission is hereby granted, free of charge, to any person obtaining a copy
14 * of this source file (the "Software"), to deal in the Software without
15 * restriction, including without limitation the rights to use, copy, modify,
16 * merge, publish, distribute, sublicense, and/or sell copies of the Software,
17 * and to permit persons to whom the Software is furnished to do so, subject to
18 * the following conditions:
20 * The above copyright notice and this permission notice shall be included in
21 * all copies or substantial portions of the Software.
23 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
24 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
25 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
26 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
27 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
28 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
33 #include <sys/cdefs.h>
34 __FBSDID("$FreeBSD$");
36 #include <sys/types.h>
37 #include <sys/cdefs.h>
38 #include <sys/errno.h>
40 #include <sys/param.h>
41 #include <sys/systm.h>
43 #include <sys/kernel.h>
44 #include <sys/malloc.h>
48 #include <machine/xen/xen-os.h>
49 #include <machine/xen/hypervisor.h>
50 #include <machine/xen/xenbus.h>
51 #include <machine/xen/hypervisor.h>
52 #include <xen/xenbus/xenbus_comms.h>
57 #define kmalloc(size, unused) malloc(size, M_DEVBUF, M_WAITOK)
58 #define BUG_ON PANIC_IF
59 #define semaphore sema
60 #define rw_semaphore sema
61 #define DEFINE_SPINLOCK(lock) struct mtx lock
62 #define DECLARE_MUTEX(lock) struct sema lock
64 #define simple_strtoul strtoul
66 struct xenbus_dev_transaction {
67 LIST_ENTRY(xenbus_dev_transaction) list;
68 struct xenbus_transaction handle;
71 struct xenbus_dev_data {
72 /* In-progress transaction. */
73 LIST_HEAD(xdd_list_head, xenbus_dev_transaction) transactions;
75 /* Partial request. */
78 struct xsd_sockmsg msg;
79 char buffer[PAGE_SIZE];
83 #define MASK_READ_IDX(idx) ((idx)&(PAGE_SIZE-1))
84 char read_buffer[PAGE_SIZE];
85 unsigned int read_cons, read_prod;
89 static struct proc_dir_entry *xenbus_dev_intf;
92 xenbus_dev_read(struct cdev *dev, struct uio *uio, int ioflag)
95 struct xenbus_dev_data *u = dev->si_drv1;
97 if (wait_event_interruptible(&u->read_waitq,
98 u->read_prod != u->read_cons))
101 for (i = 0; i < uio->uio_iov[0].iov_len; i++) {
102 if (u->read_cons == u->read_prod)
104 copyout(&u->read_buffer[MASK_READ_IDX(u->read_cons)], (char *)uio->uio_iov[0].iov_base+i, 1);
111 static void queue_reply(struct xenbus_dev_data *u,
112 char *data, unsigned int len)
116 for (i = 0; i < len; i++, u->read_prod++)
117 u->read_buffer[MASK_READ_IDX(u->read_prod)] = data[i];
119 BUG_ON((u->read_prod - u->read_cons) > sizeof(u->read_buffer));
121 wakeup(&u->read_waitq);
125 xenbus_dev_write(struct cdev *dev, struct uio *uio, int ioflag)
128 struct xenbus_dev_data *u = dev->si_drv1;
129 struct xenbus_dev_transaction *trans;
131 int len = uio->uio_iov[0].iov_len;
133 if ((len + u->len) > sizeof(u->u.buffer))
136 if (copyin(u->u.buffer + u->len, uio->uio_iov[0].iov_base, len) != 0)
140 if (u->len < (sizeof(u->u.msg) + u->u.msg.len))
143 switch (u->u.msg.type) {
144 case XS_TRANSACTION_START:
145 case XS_TRANSACTION_END:
150 case XS_GET_DOMAIN_PATH:
155 reply = xenbus_dev_request_and_reply(&u->u.msg);
157 err = PTR_ERR(reply);
159 if (u->u.msg.type == XS_TRANSACTION_START) {
160 trans = kmalloc(sizeof(*trans), GFP_KERNEL);
161 trans->handle.id = simple_strtoul(reply, NULL, 0);
162 LIST_INSERT_HEAD(&u->transactions, trans, list);
163 } else if (u->u.msg.type == XS_TRANSACTION_END) {
164 LIST_FOREACH(trans, &u->transactions,
166 if (trans->handle.id ==
169 #if 0 /* XXX does this mean the list is empty? */
170 BUG_ON(&trans->list == &u->transactions);
172 LIST_REMOVE(trans, list);
175 queue_reply(u, (char *)&u->u.msg, sizeof(u->u.msg));
176 queue_reply(u, (char *)reply, u->u.msg.len);
194 static int xenbus_dev_open(struct cdev *dev, int oflags, int devtype, struct thread *td)
196 struct xenbus_dev_data *u;
198 if (xen_start_info->store_evtchn == 0)
200 #if 0 /* XXX figure out if equiv needed */
201 nonseekable_open(inode, filp);
203 u = kmalloc(sizeof(*u), GFP_KERNEL);
207 memset(u, 0, sizeof(*u));
208 LIST_INIT(&u->transactions);
215 static int xenbus_dev_close(struct cdev *dev, int fflag, int devtype, struct thread *td)
217 struct xenbus_dev_data *u = dev->si_drv1;
218 struct xenbus_dev_transaction *trans, *tmp;
220 LIST_FOREACH_SAFE(trans, &u->transactions, list, tmp) {
221 xenbus_transaction_end(trans->handle, 1);
222 LIST_REMOVE(trans, list);
230 static struct cdevsw xenbus_dev_cdevsw = {
231 .d_version = D_VERSION,
232 .d_read = xenbus_dev_read,
233 .d_write = xenbus_dev_write,
234 .d_open = xenbus_dev_open,
235 .d_close = xenbus_dev_close,
236 .d_name = "xenbus_dev",
240 xenbus_dev_sysinit(void)
242 make_dev(&xenbus_dev_cdevsw, 0, UID_ROOT, GID_WHEEL, 0400, "xenbus");
246 SYSINIT(xenbus_dev_sysinit, SI_SUB_DRIVERS, SI_ORDER_MIDDLE, xenbus_dev_sysinit, NULL);
247 /* SYSINIT NEEDED XXX */
253 * c-file-style: "linux"
254 * indent-tabs-mode: t