libxc: osdep: add framework for abstracting access to dom0 OS hypervisor interfaces.

This patch introduces the basic infrastructure and uses it for open
and close operations on privcmd, evtchn and gnttab devices.

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

1 files changed, 50 insertions, 10 deletions

diff --git a/tools/libxc/xc_netbsd.c b/tools/libxc/xc_netbsd.c
index f60d0d4154..397c4fb71f 100644
--- a/tools/libxc/xc_netbsd.c
+++ b/tools/libxc/xc_netbsd.c
@@ -24,7 +24,7 @@
 #include <unistd.h>
 #include <fcntl.h>
 
-int xc_interface_open_core(xc_interface *xch)
+static xc_osdep_handle netbsd_privcmd_open(xc_interface *xch)
 {
     int flags, saved_errno;
     int fd = open("/kern/xen/privcmd", O_RDWR);
@@ -32,7 +32,7 @@ int xc_interface_open_core(xc_interface *xch)
     if ( fd == -1 )
     {
         PERROR("Could not obtain handle on privileged command interface");
-        return -1;
+        return XC_OSDEP_OPEN_ERROR;
     }
 
     /* Although we return the file handle as the 'xc handle' the API
@@ -51,18 +51,21 @@ int xc_interface_open_core(xc_interface *xch)
         goto error;
     }
 
-    return fd;
+    xch->fd = fd; /* Remove after transition to full xc_osdep_ops. */
+
+    return (xc_osinteface_handle)fd;
 
  error:
     saved_errno = errno;
     close(fd);
     errno = saved_errno;
-    return -1;
+    return XC_OSDEP_OPEN_ERROR;
 }
 
-int xc_interface_close_core(xc_interface *xch)
+static int netbsd_privcmd_close(xc_interface *xch, xc_osdep_handle h)
 {
-    return close(xch->fd);
+    int fd = (int)h;
+    return close(fd);
 }
 
 void *xc_map_foreign_batch(xc_interface *xch, uint32_t dom, int prot,
@@ -179,16 +182,27 @@ int do_xen_hypercall(xc_interface *xch, privcmd_hypercall_t *hypercall)
        return (hypercall->retval);
 }
 
+static struct xc_osdep_ops netbsd_privcmd_ops = {
+    .open = &netbsd_privcmd_open,
+    .close = &netbsd_privcmd_close,
+};
+
 #define EVTCHN_DEV_NAME  "/dev/xenevt"
 
-int xc_evtchn_open_core(xc_evtchn *xce)
+static xc_osdep_handle netbsd_evtchn_open(xc_evtchn *xce)
 {
-    return open(EVTCHN_DEV_NAME, O_NONBLOCK|O_RDWR);
+    int fd = open(EVTCHN_DEV_NAME, O_NONBLOCK|O_RDWR);
+    if ( fd == -1 )
+        return XC_OSDEP_OPEN_ERROR;
+
+    xce->fd = fd; /* Remove after transition to full xc_osdep_ops. */
+    return (xc_osdep_handle)fd;
 }
 
-int xc_evtchn_close_core(xc_evtchn *xce)
+static int netbsd_evtchn_close(xc_evtchn *xce, xc_osdep_handle h)
 {
-    return close(xce->fd);
+    int fd = (int)h;
+    return close(fd);
 }
 
 int xc_evtchn_fd(xc_evtchn *xce)
@@ -277,6 +291,11 @@ int xc_evtchn_unmask(xc_evtchn *xce, evtchn_port_t port)
     return write_exact(xce->fd, (char *)&port, sizeof(port));
 }
 
+static struct xc_osdep_ops netbsd_evtchn_ops = {
+    .open = &netbsd_evtchn_open,
+    .close = &netbsd_evtchn_close,
+};
+
 /* Optionally flush file to disk and discard page cache */
 void discard_file_cache(xc_interface *xch, int fd, int flush) 
 {
@@ -312,6 +331,27 @@ void discard_file_cache(xc_interface *xch, int fd, int flush)
     errno = saved_errno;
 }
 
+static struct xc_osdep_ops *netbsd_osdep_init(xc_interface *xch, enum xc_osdep_type type)
+{
+    switch ( type )
+    {
+    case XC_OSDEP_PRIVCMD:
+        return &netbsd_privcmd_ops;
+    case XC_OSDEP_EVTCHN:
+        return &netbsd_evtchn_ops;
+    case XC_OSDEP_GNTTAB:
+        ERROR("GNTTAB interface not supported on this platform");
+        return NULL;
+    default:
+        return NULL;
+    }
+}
+
+xc_osdep_info_t xc_osdep_info = {
+    .name = "Netbsd Native OS interface",
+    .init = &netbsd_osdep_init,
+};
+
 /*
  * Local variables:
  * mode: C