libxc: add abitility to dynamically load osdep.

Add a dummy backend which always returns ENOSYS. Mainly as a compile
time testbed rather than because it is a useful backend.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Ian Jackson <ian.jackson.citrix.com>

1 files changed, 206 insertions, 0 deletions

diff --git a/tools/libxc/xenctrl_osdep_ENOSYS.c b/tools/libxc/xenctrl_osdep_ENOSYS.c
new file mode 100644
index 0000000000..90ae348a58
--- /dev/null
+++ b/tools/libxc/xenctrl_osdep_ENOSYS.c
@@ -0,0 +1,206 @@
+/* Dummy backend which just logs and returns ENOSYS. */
+
+#include <errno.h>
+#include <inttypes.h>
+#include <stdlib.h>
+
+#include "xenctrl.h"
+#include "xenctrlosdep.h"
+
+#define IPRINTF(_x, _f, _a...) xc_osdep_log(_x,XTL_INFO,0, _f , ## _a)
+
+#define ERROR(_x, _m, _a...)  xc_osdep_log(_x,XTL_ERROR,XC_INTERNAL_ERROR,_m , ## _a )
+#define PERROR(_x, _m, _a...) xc_osdep_log(_x,XTL_ERROR,XC_INTERNAL_ERROR,_m \
+                  " (%d = %s)", ## _a , errno, xc_strerror(xch, errno))
+
+static xc_osdep_handle ENOSYS_privcmd_open(xc_interface *xch)
+{
+    IPRINTF(xch, "ENOSYS_privcmd: opening handle %p\n", (void *)1);
+    return (xc_osdep_handle)1; /*dummy*/
+}
+
+static int ENOSYS_privcmd_close(xc_interface *xch, xc_osdep_handle h)
+{
+    IPRINTF(xch, "ENOSYS_privcmd: closing handle %p\n", h);
+    return 0;
+}
+
+static int ENOSYS_privcmd_hypercall(xc_interface *xch, xc_osdep_handle h, privcmd_hypercall_t *hypercall)
+{
+    IPRINTF(xch, "ENOSYS_privcmd %p: hypercall: %02lld(%#llx,%#llx,%#llx,%#llx,%#llx,%#llx)\n",
+            h, hypercall->op,
+            hypercall->arg[0], hypercall->arg[1], hypercall->arg[2],
+            hypercall->arg[3], hypercall->arg[4], hypercall->arg[5]);
+    return -ENOSYS;
+}
+
+static void *ENOSYS_privcmd_map_foreign_batch(xc_interface *xch, xc_osdep_handle h, uint32_t dom, int prot,
+                                      xen_pfn_t *arr, int num)
+{
+    IPRINTF(xch, "ENOSYS_privcmd %p: map_foreign_batch: dom%d prot %#x arr %p num %d\n", h, dom, prot, arr, num);
+    return MAP_FAILED;
+}
+
+static void *ENOSYS_privcmd_map_foreign_bulk(xc_interface *xch, xc_osdep_handle h, uint32_t dom, int prot,
+                                     const xen_pfn_t *arr, int *err, unsigned int num)
+{
+    IPRINTF(xch, "ENOSYS_privcmd %p: map_foreign_buld: dom%d prot %#x arr %p err %p num %d\n", h, dom, prot, arr, err, num);
+    return MAP_FAILED;
+}
+
+static void *ENOSYS_privcmd_map_foreign_range(xc_interface *xch, xc_osdep_handle h, uint32_t dom, int size, int prot,
+                                      unsigned long mfn)
+{
+    IPRINTF(xch, "ENOSYS_privcmd %p: map_foreign_range: dom%d size %#x prot %#x mfn %ld\n", h, dom, size, prot, mfn);
+    return MAP_FAILED;
+}
+
+static void *ENOSYS_privcmd_map_foreign_ranges(xc_interface *xch, xc_osdep_handle h, uint32_t dom, size_t size, int prot,
+                                       size_t chunksize, privcmd_mmap_entry_t entries[],
+                                       int nentries)
+{
+    IPRINTF(xch, "ENOSYS_privcmd %p: map_foreign_ranges: dom%d size %zd prot %#x chunksize %zd entries %p num %d\n", h, dom, size, prot, chunksize, entries, nentries);
+    return MAP_FAILED;
+}
+
+static struct xc_osdep_ops ENOSYS_privcmd_ops =
+{
+    .open      = &ENOSYS_privcmd_open,
+    .close     = &ENOSYS_privcmd_close,
+    .u.privcmd   = {
+        .hypercall = &ENOSYS_privcmd_hypercall,
+
+        .map_foreign_batch = &ENOSYS_privcmd_map_foreign_batch,
+        .map_foreign_bulk = &ENOSYS_privcmd_map_foreign_bulk,
+        .map_foreign_range = &ENOSYS_privcmd_map_foreign_range,
+        .map_foreign_ranges = &ENOSYS_privcmd_map_foreign_ranges,
+    }
+};
+
+static xc_osdep_handle ENOSYS_evtchn_open(xc_interface *xce)
+{
+    IPRINTF(xce, "ENOSYS_evtchn: opening handle %p\n", (void *)1);
+    return (xc_osdep_handle)2; /*dummy*/
+}
+
+static int ENOSYS_evtchn_close(xc_interface *xce, xc_osdep_handle h)
+{
+    IPRINTF(xce, "ENOSYS_evtchn: closing handle %p\n", h);
+    return 0;
+}
+
+static int ENOSYS_evtchn_fd(xc_interface *xce, xc_osdep_handle h)
+{
+    IPRINTF(xce, "ENOSYS_fd %p: fd\n", h);
+    return (int)h;
+}
+
+static int ENOSYS_evtchn_notify(xc_interface *xce, xc_osdep_handle h, evtchn_port_t port)
+{
+    IPRINTF(xce, "ENOSYS_evtchn %p: notify: %d\n", h, port);
+    return -ENOSYS;
+}
+
+static int ENOSYS_evtchn_bind_unbound_port(xc_interface *xce, xc_osdep_handle h, int domid)
+{
+    IPRINTF(xce, "ENOSYS_evtchn %p: bind_unbound_port: dom%d\n", h, domid);
+    return -ENOSYS;
+}
+
+
+static int ENOSYS_evtchn_bind_interdomain(xc_interface *xce, xc_osdep_handle h, int domid, evtchn_port_t remote_port)
+{
+    IPRINTF(xce, "ENOSYS_evtchn %p: bind_interdomain: dmo%d %d\n", h, domid, remote_port);
+    return -ENOSYS;
+}
+
+
+static int ENOSYS_evtchn_bind_virq(xc_interface *xce, xc_osdep_handle h, unsigned int virq)
+{
+    IPRINTF(xce, "ENOSYS_evtchn %p: bind_virq: %d\n", h, virq);
+    return -ENOSYS;
+}
+
+
+static int ENOSYS_evtchn_unbind(xc_interface *xce, xc_osdep_handle h, evtchn_port_t port)
+{
+    IPRINTF(xce, "ENOSYS_evtchn %p: unbind: %d\n", h, port);
+    return -ENOSYS;
+}
+
+
+static evtchn_port_or_error_t ENOSYS_evtchn_pending(xc_interface *xce, xc_osdep_handle h)
+{
+    IPRINTF(xce, "ENOSYS_evtchn %p: pending\n", h);
+    return -ENOSYS;
+}
+
+static int ENOSYS_evtchn_unmask(xc_interface *xce, xc_osdep_handle h, evtchn_port_t port)
+{
+    IPRINTF(xce, "ENOSYS_evtchn %p: unmask: %d\n", h, port);
+    return -ENOSYS;
+}
+
+static struct xc_osdep_ops ENOSYS_evtchn_ops = {
+    .open = &ENOSYS_evtchn_open,
+    .close = &ENOSYS_evtchn_close,
+
+    .u.evtchn = {
+        .fd = &ENOSYS_evtchn_fd,
+
+        .notify = &ENOSYS_evtchn_notify,
+
+        .bind_unbound_port = &ENOSYS_evtchn_bind_unbound_port,
+        .bind_interdomain = &ENOSYS_evtchn_bind_interdomain,
+        .bind_virq = &ENOSYS_evtchn_bind_virq,
+
+        .unbind = &ENOSYS_evtchn_unbind,
+
+        .pending = &ENOSYS_evtchn_pending,
+        .unmask = &ENOSYS_evtchn_unmask,
+    },
+};
+
+static struct xc_osdep_ops * ENOSYS_osdep_init(xc_interface *xch, enum xc_osdep_type type)
+{
+    struct xc_osdep_ops *ops;
+
+    if (getenv("ENOSYS") == NULL)
+    {
+        PERROR(xch, "ENOSYS: not configured\n");
+        return NULL;
+    }
+
+    switch ( type )
+    {
+    case XC_OSDEP_PRIVCMD:
+        ops = &ENOSYS_privcmd_ops;
+        break;
+    case XC_OSDEP_EVTCHN:
+        ops = &ENOSYS_evtchn_ops;
+        break;
+    default:
+        ops = NULL;
+        break;
+    }
+
+    IPRINTF(xch, "ENOSYS_osdep_init: initialising handle ops at %p\n", ops);
+
+    return ops;
+}
+
+xc_osdep_info_t xc_osdep_info = {
+    .name = "Pessimistic ENOSYS OS interface",
+    .init = &ENOSYS_osdep_init,
+    .fake = 1,
+};
+
+/*
+ * Local variables:
+ * mode: C
+ * c-set-style: "BSD"
+ * c-basic-offset: 4
+ * tab-width: 4
+ * indent-tabs-mode: nil
+ * End:
+ */