This commit was manufactured by cvs2svn to create branch 'vserver'.

[linux-2.6.git] / drivers / xen / tpmback / interface.c

diff --git a/drivers/xen/tpmback/interface.c b/drivers/xen/tpmback/interface.c
new file mode 100644 (file)
index 0000000..0105bd9
--- /dev/null
+++ b/drivers/xen/tpmback/interface.c
@@ -0,0 +1,177 @@
+ /*****************************************************************************
+ * drivers/xen/tpmback/interface.c
+ *
+ * Vritual TPM interface management.
+ *
+ * Copyright (c) 2005, IBM Corporation
+ *
+ * Author: Stefan Berger, stefanb@us.ibm.com
+ *
+ * This code has been derived from drivers/xen/netback/interface.c
+ * Copyright (c) 2004, Keir Fraser
+ */
+
+#include "common.h"
+#include <xen/balloon.h>
+#include <xen/gnttab.h>
+
+static kmem_cache_t *tpmif_cachep;
+int num_frontends = 0;
+
+LIST_HEAD(tpmif_list);
+
+static tpmif_t *alloc_tpmif(domid_t domid, struct backend_info *bi)
+{
+       tpmif_t *tpmif;
+
+       tpmif = kmem_cache_alloc(tpmif_cachep, GFP_KERNEL);
+       if (!tpmif)
+               return ERR_PTR(-ENOMEM);
+
+       memset(tpmif, 0, sizeof (*tpmif));
+       tpmif->domid = domid;
+       tpmif->status = DISCONNECTED;
+       tpmif->bi = bi;
+       snprintf(tpmif->devname, sizeof(tpmif->devname), "tpmif%d", domid);
+       atomic_set(&tpmif->refcnt, 1);
+
+       tpmif->pagerange = balloon_alloc_empty_page_range(TPMIF_TX_RING_SIZE);
+       BUG_ON(tpmif->pagerange == NULL);
+       tpmif->mmap_vstart = (unsigned long)pfn_to_kaddr(
+                                           page_to_pfn(tpmif->pagerange));
+
+       list_add(&tpmif->tpmif_list, &tpmif_list);
+       num_frontends++;
+
+       return tpmif;
+}
+
+static void free_tpmif(tpmif_t * tpmif)
+{
+       num_frontends--;
+       list_del(&tpmif->tpmif_list);
+       balloon_dealloc_empty_page_range(tpmif->pagerange, TPMIF_TX_RING_SIZE);
+       kmem_cache_free(tpmif_cachep, tpmif);
+}
+
+tpmif_t *tpmif_find(domid_t domid, struct backend_info *bi)
+{
+       tpmif_t *tpmif;
+
+       list_for_each_entry(tpmif, &tpmif_list, tpmif_list) {
+               if (tpmif->bi == bi) {
+                       if (tpmif->domid == domid) {
+                               tpmif_get(tpmif);
+                               return tpmif;
+                       } else {
+                               return ERR_PTR(-EEXIST);
+                       }
+               }
+       }
+
+       return alloc_tpmif(domid, bi);
+}
+
+static int map_frontend_page(tpmif_t *tpmif, unsigned long shared_page)
+{
+       int ret;
+       struct gnttab_map_grant_ref op;
+
+       gnttab_set_map_op(&op, (unsigned long)tpmif->tx_area->addr,
+                         GNTMAP_host_map, shared_page, tpmif->domid);
+
+       lock_vm_area(tpmif->tx_area);
+       ret = HYPERVISOR_grant_table_op(GNTTABOP_map_grant_ref, &op, 1);
+       unlock_vm_area(tpmif->tx_area);
+       BUG_ON(ret);
+
+       if (op.status) {
+               DPRINTK(" Grant table operation failure !\n");
+               return op.status;
+       }
+
+       tpmif->shmem_ref = shared_page;
+       tpmif->shmem_handle = op.handle;
+
+       return 0;
+}
+
+static void unmap_frontend_page(tpmif_t *tpmif)
+{
+       struct gnttab_unmap_grant_ref op;
+       int ret;
+
+       gnttab_set_unmap_op(&op, (unsigned long)tpmif->tx_area->addr,
+                           GNTMAP_host_map, tpmif->shmem_handle);
+
+       lock_vm_area(tpmif->tx_area);
+       ret = HYPERVISOR_grant_table_op(GNTTABOP_unmap_grant_ref, &op, 1);
+       unlock_vm_area(tpmif->tx_area);
+       BUG_ON(ret);
+}
+
+int tpmif_map(tpmif_t *tpmif, unsigned long shared_page, unsigned int evtchn)
+{
+       int err;
+       struct evtchn_bind_interdomain bind_interdomain;
+
+       if (tpmif->irq) {
+               return 0;
+       }
+
+       if ((tpmif->tx_area = alloc_vm_area(PAGE_SIZE)) == NULL)
+               return -ENOMEM;
+
+       err = map_frontend_page(tpmif, shared_page);
+       if (err) {
+               free_vm_area(tpmif->tx_area);
+               return err;
+       }
+
+
+       bind_interdomain.remote_dom  = tpmif->domid;
+       bind_interdomain.remote_port = evtchn;
+
+       err = HYPERVISOR_event_channel_op(EVTCHNOP_bind_interdomain,
+                                         &bind_interdomain);
+       if (err) {
+               unmap_frontend_page(tpmif);
+               free_vm_area(tpmif->tx_area);
+               return err;
+       }
+
+       tpmif->evtchn = bind_interdomain.local_port;
+
+       tpmif->tx = (tpmif_tx_interface_t *)tpmif->tx_area->addr;
+
+       tpmif->irq = bind_evtchn_to_irqhandler(
+               tpmif->evtchn, tpmif_be_int, 0, tpmif->devname, tpmif);
+       tpmif->shmem_ref = shared_page;
+       tpmif->active = 1;
+
+       return 0;
+}
+
+void tpmif_disconnect_complete(tpmif_t *tpmif)
+{
+       if (tpmif->irq)
+               unbind_from_irqhandler(tpmif->irq, tpmif);
+
+       if (tpmif->tx) {
+               unmap_frontend_page(tpmif);
+               free_vm_area(tpmif->tx_area);
+       }
+
+       free_tpmif(tpmif);
+}
+
+void __init tpmif_interface_init(void)
+{
+       tpmif_cachep = kmem_cache_create("tpmif_cache", sizeof (tpmif_t),
+                                        0, 0, NULL, NULL);
+}
+
+void __exit tpmif_interface_exit(void)
+{
+       kmem_cache_destroy(tpmif_cachep);
+}