init gnumach copy

1 files changed, 337 insertions, 0 deletions

diff --git a/xen/store.c b/xen/store.c
new file mode 100644
index 0000000..5f5a902
--- /dev/null
+++ b/xen/store.c
@@ -0,0 +1,337 @@
+/*
+ *  Copyright (C) 2006-2009 Free Software Foundation
+ *
+ * This program is free software ; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation ; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY ; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with the program ; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <sys/types.h>
+#include <mach/mig_support.h>
+#include <machine/pmap.h>
+#include <machine/ipl.h>
+#include <kern/kalloc.h>
+#include <stdarg.h>
+#include <string.h>
+#include <alloca.h>
+#include <xen/public/xen.h>
+#include <xen/public/io/xs_wire.h>
+#include <util/atoi.h>
+#include "store.h"
+#include "ring.h"
+#include "evt.h"
+#include "xen.h"
+
+/* TODO use events instead of just yielding */
+
+/* Hypervisor part */
+
+def_simple_lock_data(static, lock);
+
+static struct xenstore_domain_interface *store;
+
+struct store_req {
+	const char *data;
+	unsigned len;
+};
+
+/* Send a request */
+static void store_put(hyp_store_transaction_t t, uint32_t type, struct store_req *req, unsigned nr_reqs) {
+	struct xsd_sockmsg head = {
+		.type = type,
+		.req_id = 0,
+		.tx_id = t,
+	};
+	unsigned totlen, len;
+	unsigned i;
+
+	totlen = 0;
+	for (i = 0; i < nr_reqs; i++)
+		totlen += req[i].len;
+	head.len = totlen;
+	totlen += sizeof(head);
+
+	if (totlen > sizeof(store->req) - 1)
+		panic("too big store message %d, max %d", totlen, (int) sizeof(store->req));
+
+	while (hyp_ring_available(store->req, store->req_prod, store->req_cons) < totlen)
+		hyp_yield();
+
+	mb();
+	hyp_ring_store(&hyp_ring_cell(store->req, store->req_prod), &head, sizeof(head), store->req, store->req + sizeof(store->req));
+	len = sizeof(head);
+	for (i=0; i<nr_reqs; i++) {
+		hyp_ring_store(&hyp_ring_cell(store->req, store->req_prod + len), req[i].data, req[i].len, store->req, store->req + sizeof(store->req));
+		len += req[i].len;
+	}
+
+	wmb();
+	store->req_prod += totlen;
+	hyp_event_channel_send(boot_info.store_evtchn);
+}
+
+static const char *errors[] = {
+	"EINVAL",
+	"EACCES",
+	"EEXIST",
+	"EISDIR",
+	"ENOENT",
+	"ENOMEM",
+	"ENOSPC",
+	"EIO",
+	"ENOTEMPTY",
+	"ENOSYS",
+	"EROFS",
+	"EBUSY",
+	"EAGAIN",
+	"EISCONN",
+	NULL,
+};
+
+/* Send a request and wait for a reply, whose header is put in head, and
+ * data is returned (beware, that's in the ring !)
+ * On error, returns NULL.  Else takes the lock and return pointer on data and
+ * store_put_wait_end shall be called after reading it.  */
+static struct xsd_sockmsg head;
+const char *hyp_store_error;
+
+static void *store_put_wait(hyp_store_transaction_t t, uint32_t type, struct store_req *req, unsigned nr_reqs) {
+	unsigned len;
+	const char **error;
+	void *data;
+
+	simple_lock(&lock);
+	store_put(t, type, req, nr_reqs);
+again:
+	while (store->rsp_prod - store->rsp_cons < sizeof(head))
+		hyp_yield();
+	rmb();
+	hyp_ring_fetch(&head, &hyp_ring_cell(store->rsp, store->rsp_cons), sizeof(head), store->rsp, store->rsp + sizeof(store->rsp));
+	len = sizeof(head) + head.len;
+	while (store->rsp_prod - store->rsp_cons < len)
+		hyp_yield();
+	rmb();
+	if (head.type == XS_WATCH_EVENT) {
+		/* Spurious watch event, drop */
+		store->rsp_cons += sizeof(head) + head.len;
+		hyp_event_channel_send(boot_info.store_evtchn);
+		goto again;
+	}
+	data = &hyp_ring_cell(store->rsp, store->rsp_cons + sizeof(head));
+	if (head.len <= 10) {
+		char c[10];
+		hyp_ring_fetch(c, data, head.len, store->rsp, store->rsp + sizeof(store->rsp));
+		for (error = errors; *error; error++) {
+			if (head.len == strlen(*error) + 1 && !memcmp(*error, c, head.len)) {
+				hyp_store_error = *error;
+				store->rsp_cons += len;
+				hyp_event_channel_send(boot_info.store_evtchn);
+				simple_unlock(&lock);
+				return NULL;
+			}
+		}
+	}
+	return data;
+}
+
+/* Must be called after each store_put_wait.  Releases lock.  */
+static void store_put_wait_end(void) {
+	mb();
+	store->rsp_cons += sizeof(head) + head.len;
+	hyp_event_channel_send(boot_info.store_evtchn);
+	simple_unlock(&lock);
+}
+
+/* Start a transaction.  */
+hyp_store_transaction_t hyp_store_transaction_start(void) {
+	struct store_req req = {
+		.data = "",
+		.len = 1,
+	};
+	char *rep;
+	char *s;
+	int i;
+
+	rep = store_put_wait(0, XS_TRANSACTION_START, &req, 1);
+	if (!rep)
+		panic("couldn't start transaction (%s)", hyp_store_error);
+	s = alloca(head.len);
+	hyp_ring_fetch(s, rep, head.len, store->rsp, store->rsp + sizeof(store->rsp));
+	mach_atoi((u_char*) s, &i);
+	if (i == MACH_ATOI_DEFAULT)
+		panic("bogus transaction id len %d '%s'", head.len, s);
+	store_put_wait_end();
+	return i;
+}
+
+/* Stop a transaction.  */
+int hyp_store_transaction_stop(hyp_store_transaction_t t) {
+	struct store_req req = {
+		.data = "T",
+		.len = 2,
+	};
+	int ret = 1;
+	void *rep;
+	rep = store_put_wait(t, XS_TRANSACTION_END, &req, 1);
+	if (!rep)
+		return 0;
+	store_put_wait_end();
+	return ret;
+}
+
+/* List a directory: returns an array to file names, terminated by NULL.  Free
+ * with kfree.  */
+char **hyp_store_ls(hyp_store_transaction_t t, int n, ...) {
+	struct store_req req[n];
+	va_list listp;
+	int i;
+	char *rep;
+	char *c;
+	char **res, **rsp;
+
+	va_start (listp, n);
+	for (i = 0; i < n; i++) {
+		req[i].data = va_arg(listp, char *);
+		req[i].len = strlen(req[i].data);
+	}
+	req[n - 1].len++;
+	va_end (listp);
+
+	rep = store_put_wait(t, XS_DIRECTORY, req, n);
+	if (!rep)
+		return NULL;
+	i = 0;
+	for (	c = rep, n = 0;
+		n < head.len;
+		n += hyp_ring_next_word(&c, store->rsp, store->rsp + sizeof(store->rsp)) + 1)
+		i++;
+	res = (void*) kalloc((i + 1) * sizeof(char*) + head.len);
+	if (!res)
+		hyp_store_error = "ENOMEM";
+	else {
+		hyp_ring_fetch(res + (i + 1), rep, head.len, store->rsp, store->rsp + sizeof(store->rsp));
+		rsp = res;
+		for (c = (char*) (res + (i + 1)); i; i--, c += strlen(c) + 1)
+			*rsp++ = c;
+		*rsp = NULL;
+	}
+	store_put_wait_end();
+	return res;
+}
+
+/* Get the value of an entry, va version.  */
+static void *hyp_store_read_va(hyp_store_transaction_t t, int n, va_list listp) {
+	struct store_req req[n];
+	int i;
+	void *rep;
+	char *res;
+
+	for (i = 0; i < n; i++) {
+		req[i].data = va_arg(listp, char *);
+		req[i].len = strlen(req[i].data);
+	}
+	req[n - 1].len++;
+
+	rep = store_put_wait(t, XS_READ, req, n);
+	if (!rep)
+		return NULL;
+	res = (void*) kalloc(head.len + 1);
+	if (!res)
+		hyp_store_error = "ENOMEM";
+	else {
+		hyp_ring_fetch(res, rep, head.len, store->rsp, store->rsp + sizeof(store->rsp));
+		res[head.len] = 0;
+	}
+	store_put_wait_end();
+	return res;
+}
+
+/* Get the value of an entry.  Free with kfree.  */
+void *hyp_store_read(hyp_store_transaction_t t, int n, ...) {
+	va_list listp;
+	char *res;
+
+	va_start(listp, n);
+	res = hyp_store_read_va(t, n, listp);
+	va_end(listp);
+	return res;
+}
+
+/* Get the integer value of an entry, -1 on error.  */
+int hyp_store_read_int(hyp_store_transaction_t t, int n, ...) {
+	va_list listp;
+	char *res;
+	int i;
+
+	va_start(listp, n);
+	res = hyp_store_read_va(t, n, listp);
+	va_end(listp);
+	if (!res)
+		return -1;
+	mach_atoi((u_char *) res, &i);
+	if (i == MACH_ATOI_DEFAULT)
+		printf("bogus integer '%s'\n", res);
+	kfree((vm_offset_t) res, strlen(res)+1);
+	return i;
+}
+
+/* Set the value of an entry.  */
+char *hyp_store_write(hyp_store_transaction_t t, const char *data, int n, ...) {
+	struct store_req req[n + 1];
+	va_list listp;
+	int i;
+	void *rep;
+	char *res;
+
+	va_start (listp, n);
+	for (i = 0; i < n; i++) {
+		req[i].data = va_arg(listp, char *);
+		req[i].len = strlen(req[i].data);
+	}
+	req[n - 1].len++;
+	req[n].data = data;
+	req[n].len = strlen (data);
+	va_end (listp);
+
+	rep = store_put_wait (t, XS_WRITE, req, n + 1);
+	if (!rep)
+		return NULL;
+	res = (void*) kalloc(head.len + 1);
+	if (!res)
+		hyp_store_error = NULL;
+	else {
+		hyp_ring_fetch(res, rep, head.len, store->rsp, store->rsp + sizeof(store->rsp));
+		res[head.len] = 0;
+	}
+	store_put_wait_end();
+	return res;
+}
+
+static void hyp_store_handler(int unit)
+{
+	thread_wakeup(&boot_info.store_evtchn);
+}
+
+/* Map store's shared page.  */
+void hyp_store_init(void)
+{
+	if (store)
+		return;
+	simple_lock_init(&lock);
+	store = (void*) mfn_to_kv(boot_info.store_mfn);
+#ifdef	MACH_PV_PAGETABLES
+	pmap_set_page_readwrite(store);
+#endif	/* MACH_PV_PAGETABLES */
+	/* SPL sched */
+	hyp_evt_handler(boot_info.store_evtchn, hyp_store_handler, 0, SPL7);
+}