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-rw-r--r--sys/xen/xenbus/xenbus_xs.c960
1 files changed, 0 insertions, 960 deletions
diff --git a/sys/xen/xenbus/xenbus_xs.c b/sys/xen/xenbus/xenbus_xs.c
deleted file mode 100644
index 90c32e1..0000000
--- a/sys/xen/xenbus/xenbus_xs.c
+++ /dev/null
@@ -1,960 +0,0 @@
-/******************************************************************************
- * xenbus_xs.c
- *
- * This is the kernel equivalent of the "xs" library. We don't need everything
- * and we use xenbus_comms for communication.
- *
- * Copyright (C) 2005 Rusty Russell, IBM Corporation
- *
- * This file may be 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.
- */
-
-
-#include <sys/cdefs.h>
-__FBSDID("$FreeBSD$");
-
-#include <sys/param.h>
-#include <sys/types.h>
-#include <sys/cdefs.h>
-#include <sys/unistd.h>
-#include <sys/errno.h>
-#include <sys/uio.h>
-#include <sys/kernel.h>
-#include <sys/time.h>
-#include <sys/lock.h>
-#include <sys/mutex.h>
-#include <sys/sx.h>
-#include <sys/sema.h>
-#include <sys/syslog.h>
-#include <sys/malloc.h>
-#include <sys/libkern.h>
-#include <sys/systm.h>
-#include <sys/proc.h>
-#include <sys/kthread.h>
-
-#include <machine/xen/xen-os.h>
-#include <machine/xen/hypervisor.h>
-#include <machine/xen/xenbus.h>
-#include <machine/stdarg.h>
-
-#include <xen/xenbus/xenbus_comms.h>
-static int xs_process_msg(enum xsd_sockmsg_type *type);
-
-#define kmalloc(size, unused) malloc(size, M_DEVBUF, M_WAITOK)
-#define BUG_ON PANIC_IF
-#define DEFINE_SPINLOCK(lock) struct mtx lock
-#define u32 uint32_t
-#define list_del(head, ent) TAILQ_REMOVE(head, ent, list)
-#define simple_strtoul strtoul
-#define ARRAY_SIZE(x) (sizeof(x)/sizeof(x[0]))
-#define list_empty TAILQ_EMPTY
-
-#define streq(a, b) (strcmp((a), (b)) == 0)
-int xenwatch_running = 0;
-int xenbus_running = 0;
-
-struct kvec {
- const void *iov_base;
- size_t iov_len;
-};
-
-struct xs_stored_msg {
- TAILQ_ENTRY(xs_stored_msg) list;
-
- struct xsd_sockmsg hdr;
-
- union {
- /* Queued replies. */
- struct {
- char *body;
- } reply;
-
- /* Queued watch events. */
- struct {
- struct xenbus_watch *handle;
- char **vec;
- unsigned int vec_size;
- } watch;
- } u;
-};
-
-struct xs_handle {
- /* A list of replies. Currently only one will ever be outstanding. */
- TAILQ_HEAD(xs_handle_list, xs_stored_msg) reply_list;
- struct mtx reply_lock;
- int reply_waitq;
-
- /* One request at a time. */
- struct sx request_mutex;
-
- /* Protect transactions against save/restore. */
- struct sx suspend_mutex;
-};
-
-static struct xs_handle xs_state;
-
-/* List of registered watches, and a lock to protect it. */
-static LIST_HEAD(watch_list_head, xenbus_watch) watches;
-static DEFINE_SPINLOCK(watches_lock);
-/* List of pending watch callback events, and a lock to protect it. */
-static TAILQ_HEAD(event_list_head, xs_stored_msg) watch_events;
-static DEFINE_SPINLOCK(watch_events_lock);
-/*
- * Details of the xenwatch callback kernel thread. The thread waits on the
- * watch_events_waitq for work to do (queued on watch_events list). When it
- * wakes up it acquires the xenwatch_mutex before reading the list and
- * carrying out work.
- */
-static pid_t xenwatch_pid;
-struct sx xenwatch_mutex;
-static int watch_events_waitq;
-
-static int get_error(const char *errorstring)
-{
- unsigned int i;
-
- for (i = 0; !streq(errorstring, xsd_errors[i].errstring); i++) {
- if (i == ARRAY_SIZE(xsd_errors) - 1) {
- log(LOG_WARNING, "XENBUS xen store gave: unknown error %s",
- errorstring);
- return EINVAL;
- }
- }
- return xsd_errors[i].errnum;
-}
-
-extern void idle_block(void);
-extern void kdb_backtrace(void);
-
-static void *read_reply(enum xsd_sockmsg_type *type, unsigned int *len)
-{
- struct xs_stored_msg *msg;
- char *body;
- int i, err;
- enum xsd_sockmsg_type itype = *type;
-
- printf("read_reply ");
- if (xenbus_running == 0) {
- /*
- * Give other domain time to run :-/
- */
- for (i = 0; i < 1000000 && (xenbus_running == 0); i++) {
- err = xs_process_msg(type);
-
- if ((err == 0)
- && (*type != XS_WATCH_EVENT))
- break;
-
- HYPERVISOR_yield();
- }
-
- if (list_empty(&xs_state.reply_list)) {
- printf("giving up and returning an error type=%d\n",
- *type);
- kdb_backtrace();
- return (ERR_PTR(-1));
- }
-
- }
-
- mtx_lock(&xs_state.reply_lock);
- if (xenbus_running) {
- while (list_empty(&xs_state.reply_list)) {
- mtx_unlock(&xs_state.reply_lock);
- wait_event_interruptible(&xs_state.reply_waitq,
- !list_empty(&xs_state.reply_list));
-
- mtx_lock(&xs_state.reply_lock);
- }
- }
-
- msg = TAILQ_FIRST(&xs_state.reply_list);
- list_del(&xs_state.reply_list, msg);
-
- mtx_unlock(&xs_state.reply_lock);
-
- printf("itype=%d htype=%d ", itype, msg->hdr.type);
- *type = msg->hdr.type;
- if (len)
- *len = msg->hdr.len;
- body = msg->u.reply.body;
-
- kfree(msg);
- if (len)
- printf("len=%d\n", *len);
- else
- printf("len=NULL\n");
- return body;
-}
-
-#if 0
-/* Emergency write. UNUSED*/
-void xenbus_debug_write(const char *str, unsigned int count)
-{
- struct xsd_sockmsg msg = { 0 };
-
- msg.type = XS_DEBUG;
- msg.len = sizeof("print") + count + 1;
-
- sx_xlock(&xs_state.request_mutex);
- xb_write(&msg, sizeof(msg));
- xb_write("print", sizeof("print"));
- xb_write(str, count);
- xb_write("", 1);
- sx_xunlock(&xs_state.request_mutex);
-}
-
-#endif
-void *xenbus_dev_request_and_reply(struct xsd_sockmsg *msg)
-{
- void *ret;
- struct xsd_sockmsg req_msg = *msg;
- int err;
-
- if (req_msg.type == XS_TRANSACTION_START)
- sx_slock(&xs_state.suspend_mutex);
-
- sx_xlock(&xs_state.request_mutex);
-
- err = xb_write(msg, sizeof(*msg) + msg->len);
- if (err) {
- msg->type = XS_ERROR;
- ret = ERR_PTR(err);
- } else {
- ret = read_reply(&msg->type, &msg->len);
- }
-
- sx_xunlock(&xs_state.request_mutex);
-
- if ((msg->type == XS_TRANSACTION_END) ||
- ((req_msg.type == XS_TRANSACTION_START) &&
- (msg->type == XS_ERROR)))
- sx_sunlock(&xs_state.suspend_mutex);
-
- return ret;
-}
-
-static int xenwatch_inline;
-
-/* Send message to xs, get kmalloc'ed reply. ERR_PTR() on error. */
-static void *xs_talkv(struct xenbus_transaction t,
- enum xsd_sockmsg_type type,
- const struct kvec *iovec,
- unsigned int num_vecs,
- unsigned int *len)
-{
- struct xsd_sockmsg msg;
- void *ret = NULL;
- unsigned int i;
- int err;
-
- msg.tx_id = t.id;
- msg.req_id = 0;
- msg.type = type;
- msg.len = 0;
- for (i = 0; i < num_vecs; i++)
- msg.len += iovec[i].iov_len;
-
- printf("xs_talkv ");
-
- sx_xlock(&xs_state.request_mutex);
-
- err = xb_write(&msg, sizeof(msg));
- if (err) {
- sx_xunlock(&xs_state.request_mutex);
- printf("xs_talkv failed %d\n", err);
- return ERR_PTR(err);
- }
-
- for (i = 0; i < num_vecs; i++) {
- err = xb_write(iovec[i].iov_base, iovec[i].iov_len);;
- if (err) {
- sx_xunlock(&xs_state.request_mutex);
- printf("xs_talkv failed %d\n", err);
- return ERR_PTR(err);
- }
- }
-
- ret = read_reply(&msg.type, len);
-
- sx_xunlock(&xs_state.request_mutex);
-
- if (IS_ERR(ret))
- return ret;
-
- if (msg.type == XS_ERROR) {
- err = get_error(ret);
- kfree(ret);
- return ERR_PTR(-err);
- }
-
- if ((xenwatch_running == 0) && (xenwatch_inline == 0)) {
- xenwatch_inline = 1;
- while (!TAILQ_EMPTY(&watch_events)
- && xenwatch_running == 0) {
-
- struct xs_stored_msg *wmsg = TAILQ_FIRST(&watch_events);
- list_del(&watch_events, wmsg);
- printf("handling %p ...", wmsg->u.watch.handle->callback);
-
- wmsg->u.watch.handle->callback(
- wmsg->u.watch.handle,
- (const char **)wmsg->u.watch.vec,
- wmsg->u.watch.vec_size);
- printf("... %p done\n", wmsg->u.watch.handle->callback);
- kfree(wmsg->u.watch.vec);
- kfree(wmsg);
- }
- xenwatch_inline = 0;
- }
- BUG_ON(msg.type != type);
-
- return ret;
-}
-
-/* Simplified version of xs_talkv: single message. */
-static void *xs_single(struct xenbus_transaction t,
- enum xsd_sockmsg_type type,
- const char *string,
- unsigned int *len)
-{
- struct kvec iovec;
-
- printf("xs_single %s ", string);
- iovec.iov_base = (const void *)string;
- iovec.iov_len = strlen(string) + 1;
- return xs_talkv(t, type, &iovec, 1, len);
-}
-
-/* Many commands only need an ack, don't care what it says. */
-static int xs_error(char *reply)
-{
- if (IS_ERR(reply))
- return PTR_ERR(reply);
- kfree(reply);
- return 0;
-}
-
-static unsigned int count_strings(const char *strings, unsigned int len)
-{
- unsigned int num;
- const char *p;
-
- for (p = strings, num = 0; p < strings + len; p += strlen(p) + 1)
- num++;
-
- return num;
-}
-
-/* Return the path to dir with /name appended. Buffer must be kfree()'ed. */
-static char *join(const char *dir, const char *name)
-{
- char *buffer;
-
- buffer = kmalloc(strlen(dir) + strlen("/") + strlen(name) + 1,
- GFP_KERNEL);
- if (buffer == NULL)
- return ERR_PTR(-ENOMEM);
-
- strcpy(buffer, dir);
- if (!streq(name, "")) {
- strcat(buffer, "/");
- strcat(buffer, name);
- }
-
- return buffer;
-}
-
-static char **split(char *strings, unsigned int len, unsigned int *num)
-{
- char *p, **ret;
-
- /* Count the strings. */
- *num = count_strings(strings, len) + 1;
-
- /* Transfer to one big alloc for easy freeing. */
- ret = kmalloc(*num * sizeof(char *) + len, GFP_KERNEL);
- if (!ret) {
- kfree(strings);
- return ERR_PTR(-ENOMEM);
- }
- memcpy(&ret[*num], strings, len);
- kfree(strings);
-
- strings = (char *)&ret[*num];
- for (p = strings, *num = 0; p < strings + len; p += strlen(p) + 1)
- ret[(*num)++] = p;
-
- ret[*num] = strings + len;
-
- return ret;
-}
-
-char **xenbus_directory(struct xenbus_transaction t,
- const char *dir, const char *node, unsigned int *num)
-{
- char *strings, *path;
- unsigned int len = 0;
-
- path = join(dir, node);
- if (IS_ERR(path))
- return (char **)path;
-
- strings = xs_single(t, XS_DIRECTORY, path, &len);
- kfree(path);
- if (IS_ERR(strings))
- return (char **)strings;
-
- return split(strings, len, num);
-}
-EXPORT_SYMBOL(xenbus_directory);
-
-/* Check if a path exists. Return 1 if it does. */
-int xenbus_exists(struct xenbus_transaction t,
- const char *dir, const char *node)
-{
- char **d;
- int dir_n;
-
- d = xenbus_directory(t, dir, node, &dir_n);
- if (IS_ERR(d))
- return 0;
- kfree(d);
- return 1;
-}
-EXPORT_SYMBOL(xenbus_exists);
-
-/* Get the value of a single file.
- * Returns a kmalloced value: call free() on it after use.
- * len indicates length in bytes.
- */
-void *xenbus_read(struct xenbus_transaction t,
- const char *dir, const char *node, unsigned int *len)
-{
- char *path;
- void *ret;
-
- path = join(dir, node);
- if (IS_ERR(path))
- return (void *)path;
-
- printf("xs_read ");
- ret = xs_single(t, XS_READ, path, len);
- kfree(path);
- return ret;
-}
-EXPORT_SYMBOL(xenbus_read);
-
-/* Write the value of a single file.
- * Returns -err on failure.
- */
-int xenbus_write(struct xenbus_transaction t,
- const char *dir, const char *node, const char *string)
-{
- char *path;
- struct kvec iovec[2];
- int ret;
-
- path = join(dir, node);
- if (IS_ERR(path))
- return PTR_ERR(path);
-
- iovec[0].iov_base = path;
- iovec[0].iov_len = strlen(path) + 1;
- iovec[1].iov_base = string;
- iovec[1].iov_len = strlen(string);
-
- printf("xenbus_write dir=%s val=%s ", dir, string);
- ret = xs_error(xs_talkv(t, XS_WRITE, iovec, ARRAY_SIZE(iovec), NULL));
- kfree(path);
- return ret;
-}
-EXPORT_SYMBOL(xenbus_write);
-
-/* Create a new directory. */
-int xenbus_mkdir(struct xenbus_transaction t,
- const char *dir, const char *node)
-{
- char *path;
- int ret;
-
- path = join(dir, node);
- if (IS_ERR(path))
- return PTR_ERR(path);
-
- ret = xs_error(xs_single(t, XS_MKDIR, path, NULL));
- kfree(path);
- return ret;
-}
-EXPORT_SYMBOL(xenbus_mkdir);
-
-/* Destroy a file or directory (directories must be empty). */
-int xenbus_rm(struct xenbus_transaction t, const char *dir, const char *node)
-{
- char *path;
- int ret;
-
- path = join(dir, node);
- if (IS_ERR(path))
- return PTR_ERR(path);
-
- ret = xs_error(xs_single(t, XS_RM, path, NULL));
- kfree(path);
- return ret;
-}
-EXPORT_SYMBOL(xenbus_rm);
-
-/* Start a transaction: changes by others will not be seen during this
- * transaction, and changes will not be visible to others until end.
- */
-int xenbus_transaction_start(struct xenbus_transaction *t)
-{
- char *id_str;
-
- sx_slock(&xs_state.suspend_mutex);
- id_str = xs_single(XBT_NIL, XS_TRANSACTION_START, "", NULL);
- if (IS_ERR(id_str)) {
- sx_sunlock(&xs_state.suspend_mutex);
- return PTR_ERR(id_str);
- }
-
- t->id = simple_strtoul(id_str, NULL, 0);
- kfree(id_str);
-
- return 0;
-}
-EXPORT_SYMBOL(xenbus_transaction_start);
-
-/* End a transaction.
- * If abandon is true, transaction is discarded instead of committed.
- */
-int xenbus_transaction_end(struct xenbus_transaction t, int abort)
-{
- char abortstr[2];
- int err;
-
- if (abort)
- strcpy(abortstr, "F");
- else
- strcpy(abortstr, "T");
-
- printf("xenbus_transaction_end ");
- err = xs_error(xs_single(t, XS_TRANSACTION_END, abortstr, NULL));
-
- sx_sunlock(&xs_state.suspend_mutex);
-
- return err;
-}
-EXPORT_SYMBOL(xenbus_transaction_end);
-
-/* Single read and scanf: returns -errno or num scanned. */
-int xenbus_scanf(struct xenbus_transaction t,
- const char *dir, const char *node, const char *fmt, ...)
-{
- va_list ap;
- int ret;
- char *val;
-
- val = xenbus_read(t, dir, node, NULL);
- if (IS_ERR(val))
- return PTR_ERR(val);
-
- va_start(ap, fmt);
- ret = vsscanf(val, fmt, ap);
- va_end(ap);
- kfree(val);
- /* Distinctive errno. */
- if (ret == 0)
- return -ERANGE;
- return ret;
-}
-EXPORT_SYMBOL(xenbus_scanf);
-
-/* Single printf and write: returns -errno or 0. */
-int xenbus_printf(struct xenbus_transaction t,
- const char *dir, const char *node, const char *fmt, ...)
-{
- va_list ap;
- int ret;
-#define PRINTF_BUFFER_SIZE 4096
- char *printf_buffer;
-
- printf_buffer = kmalloc(PRINTF_BUFFER_SIZE, GFP_KERNEL);
- if (printf_buffer == NULL)
- return -ENOMEM;
-
- va_start(ap, fmt);
- ret = vsnprintf(printf_buffer, PRINTF_BUFFER_SIZE, fmt, ap);
- va_end(ap);
-
- BUG_ON(ret > PRINTF_BUFFER_SIZE-1);
- ret = xenbus_write(t, dir, node, printf_buffer);
-
- kfree(printf_buffer);
-
- return ret;
-}
-EXPORT_SYMBOL(xenbus_printf);
-
-/* Takes tuples of names, scanf-style args, and void **, NULL terminated. */
-int xenbus_gather(struct xenbus_transaction t, const char *dir, ...)
-{
- va_list ap;
- const char *name;
- int i, ret = 0;
-
- for (i = 0; i < 10000; i++)
- HYPERVISOR_yield();
-
- printf("gather ");
- va_start(ap, dir);
- while (ret == 0 && (name = va_arg(ap, char *)) != NULL) {
- const char *fmt = va_arg(ap, char *);
- void *result = va_arg(ap, void *);
- char *p;
-
- p = xenbus_read(t, dir, name, NULL);
- if (IS_ERR(p)) {
- ret = PTR_ERR(p);
- break;
- }
- printf(" %s ", p);
- if (fmt) {
- if (sscanf(p, fmt, result) == 0)
- ret = -EINVAL;
- kfree(p);
- } else
- *(char **)result = p;
- }
- va_end(ap);
- printf("\n");
- return ret;
-}
-EXPORT_SYMBOL(xenbus_gather);
-
-static int xs_watch(const char *path, const char *token)
-{
- struct kvec iov[2];
-
- iov[0].iov_base = path;
- iov[0].iov_len = strlen(path) + 1;
- iov[1].iov_base = token;
- iov[1].iov_len = strlen(token) + 1;
-
- return xs_error(xs_talkv(XBT_NIL, XS_WATCH, iov,
- ARRAY_SIZE(iov), NULL));
-}
-
-static int xs_unwatch(const char *path, const char *token)
-{
- struct kvec iov[2];
-
- iov[0].iov_base = path;
- iov[0].iov_len = strlen(path) + 1;
- iov[1].iov_base = token;
- iov[1].iov_len = strlen(token) + 1;
-
- return xs_error(xs_talkv(XBT_NIL, XS_UNWATCH, iov,
- ARRAY_SIZE(iov), NULL));
-}
-
-static struct xenbus_watch *find_watch(const char *token)
-{
- struct xenbus_watch *i, *cmp;
-
- cmp = (void *)simple_strtoul(token, NULL, 16);
-
- LIST_FOREACH(i, &watches, list)
- if (i == cmp)
- return i;
-
- return NULL;
-}
-
-/* Register callback to watch this node. */
-int register_xenbus_watch(struct xenbus_watch *watch)
-{
- /* Pointer in ascii is the token. */
- char token[sizeof(watch) * 2 + 1];
- int err;
-
- sprintf(token, "%lX", (long)watch);
-
- sx_slock(&xs_state.suspend_mutex);
-
- mtx_lock(&watches_lock);
- BUG_ON(find_watch(token) != NULL);
- LIST_INSERT_HEAD(&watches, watch, list);
- mtx_unlock(&watches_lock);
-
- err = xs_watch(watch->node, token);
-
- /* Ignore errors due to multiple registration. */
- if ((err != 0) && (err != -EEXIST)) {
- mtx_lock(&watches_lock);
- LIST_REMOVE(watch, list);
- mtx_unlock(&watches_lock);
- }
-
- sx_sunlock(&xs_state.suspend_mutex);
-
- return err;
-}
-EXPORT_SYMBOL(register_xenbus_watch);
-
-void unregister_xenbus_watch(struct xenbus_watch *watch)
-{
- struct xs_stored_msg *msg, *tmp;
- char token[sizeof(watch) * 2 + 1];
- int err;
-
- sprintf(token, "%lX", (long)watch);
-
- sx_slock(&xs_state.suspend_mutex);
-
- mtx_lock(&watches_lock);
- BUG_ON(!find_watch(token));
- LIST_REMOVE(watch, list);
- mtx_unlock(&watches_lock);
-
- err = xs_unwatch(watch->node, token);
- if (err)
- log(LOG_WARNING, "XENBUS Failed to release watch %s: %i\n",
- watch->node, err);
-
- sx_sunlock(&xs_state.suspend_mutex);
-
- /* Cancel pending watch events. */
- mtx_lock(&watch_events_lock);
- TAILQ_FOREACH_SAFE(msg, &watch_events, list, tmp) {
- if (msg->u.watch.handle != watch)
- continue;
- list_del(&watch_events, msg);
- kfree(msg->u.watch.vec);
- kfree(msg);
- }
- mtx_unlock(&watch_events_lock);
-
- /* Flush any currently-executing callback, unless we are it. :-) */
- if (curproc->p_pid != xenwatch_pid) {
- sx_xlock(&xenwatch_mutex);
- sx_xunlock(&xenwatch_mutex);
- }
-}
-EXPORT_SYMBOL(unregister_xenbus_watch);
-
-void xs_suspend(void)
-{
- sx_xlock(&xs_state.suspend_mutex);
- sx_xlock(&xs_state.request_mutex);
-}
-
-void xs_resume(void)
-{
- struct xenbus_watch *watch;
- char token[sizeof(watch) * 2 + 1];
-
- sx_xunlock(&xs_state.request_mutex);
-
- /* No need for watches_lock: the suspend_mutex is sufficient. */
- LIST_FOREACH(watch, &watches, list) {
- sprintf(token, "%lX", (long)watch);
- xs_watch(watch->node, token);
- }
-
- sx_xunlock(&xs_state.suspend_mutex);
-}
-
-static void xenwatch_thread(void *unused)
-{
- struct xs_stored_msg *msg;
-
- xenwatch_running = 1;
-
- DELAY(100000);
- while (xenwatch_inline) {
- printf("xenwatch inline still running\n");
- DELAY(100000);
- }
-
-
- for (;;) {
-
- while (list_empty(&watch_events))
- tsleep(&watch_events_waitq,
- PWAIT | PCATCH, "waitev", hz/10);
-
- sx_xlock(&xenwatch_mutex);
-
- mtx_lock(&watch_events_lock);
- msg = TAILQ_FIRST(&watch_events);
- if (msg)
- list_del(&watch_events, msg);
- mtx_unlock(&watch_events_lock);
-
- if (msg != NULL) {
- msg->u.watch.handle->callback(
- msg->u.watch.handle,
- (const char **)msg->u.watch.vec,
- msg->u.watch.vec_size);
- kfree(msg->u.watch.vec);
- kfree(msg);
- }
-
- sx_xunlock(&xenwatch_mutex);
- }
-}
-
-static int xs_process_msg(enum xsd_sockmsg_type *type)
-{
- struct xs_stored_msg *msg;
- char *body;
- int err;
-
- msg = kmalloc(sizeof(*msg), GFP_KERNEL);
- if (msg == NULL)
- return -ENOMEM;
-
- err = xb_read(&msg->hdr, sizeof(msg->hdr));
- if (err) {
- kfree(msg);
- return err;
- }
-
- body = kmalloc(msg->hdr.len + 1, GFP_KERNEL);
- if (body == NULL) {
- kfree(msg);
- return -ENOMEM;
- }
-
- err = xb_read(body, msg->hdr.len);
- if (err) {
- kfree(body);
- kfree(msg);
- return err;
- }
- body[msg->hdr.len] = '\0';
-
- *type = msg->hdr.type;
- if (msg->hdr.type == XS_WATCH_EVENT) {
- msg->u.watch.vec = split(body, msg->hdr.len,
- &msg->u.watch.vec_size);
- if (IS_ERR(msg->u.watch.vec)) {
- kfree(msg);
- return PTR_ERR(msg->u.watch.vec);
- }
-
- mtx_lock(&watches_lock);
- msg->u.watch.handle = find_watch(
- msg->u.watch.vec[XS_WATCH_TOKEN]);
- if (msg->u.watch.handle != NULL) {
- mtx_lock(&watch_events_lock);
- TAILQ_INSERT_TAIL(&watch_events, msg, list);
- wakeup(&watch_events_waitq);
- mtx_unlock(&watch_events_lock);
- } else {
- kfree(msg->u.watch.vec);
- kfree(msg);
- }
- mtx_unlock(&watches_lock);
- } else {
- printf("event=%d ", *type);
- msg->u.reply.body = body;
- mtx_lock(&xs_state.reply_lock);
- TAILQ_INSERT_TAIL(&xs_state.reply_list, msg, list);
- wakeup(&xs_state.reply_waitq);
- mtx_unlock(&xs_state.reply_lock);
- }
- if (*type == XS_WATCH_EVENT)
- printf("\n");
-
- return 0;
-}
-
-static void xenbus_thread(void *unused)
-{
- int err;
- enum xsd_sockmsg_type type;
-
- DELAY(10000);
- xenbus_running = 1;
- tsleep(&lbolt, 0, "xenbus", hz/10);
-
- for (;;) {
- err = xs_process_msg(&type);
- if (err)
- printf("XENBUS error %d while reading "
- "message\n", err);
-
- }
-}
-
-int xs_init(void)
-{
- int err;
- struct proc *p;
-
- TAILQ_INIT(&xs_state.reply_list);
- TAILQ_INIT(&watch_events);
- sx_init(&xenwatch_mutex, "xenwatch");
-
-
- mtx_init(&xs_state.reply_lock, "state reply", NULL, MTX_DEF);
- sx_init(&xs_state.request_mutex, "xenstore request");
- sx_init(&xs_state.suspend_mutex, "xenstore suspend");
-
-
-#if 0
- mtx_init(&xs_state.suspend_mutex, "xenstore suspend", NULL, MTX_DEF);
- sema_init(&xs_state.request_mutex, 1, "xenstore request");
- sema_init(&xenwatch_mutex, 1, "xenwatch");
-#endif
- mtx_init(&watches_lock, "watches", NULL, MTX_DEF);
- mtx_init(&watch_events_lock, "watch events", NULL, MTX_DEF);
-
- /* Initialize the shared memory rings to talk to xenstored */
- err = xb_init_comms();
- if (err)
- return err;
-
- err = kthread_create(xenwatch_thread, NULL, &p,
- RFHIGHPID, 0, "xenwatch");
- if (err)
- return err;
- xenwatch_pid = p->p_pid;
-
- err = kthread_create(xenbus_thread, NULL, NULL,
- RFHIGHPID, 0, "xenbus");
-
- return err;
-}
-
-
-/*
- * Local variables:
- * c-file-style: "bsd"
- * indent-tabs-mode: t
- * c-indent-level: 4
- * c-basic-offset: 8
- * tab-width: 4
- * End:
- */
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