Add commands to automatically prep devices for pass-through

diff -r 804eb2962984 -r a2b528299c12 tools/libxl/libxl_pci.c
@@ -327,6 +327,36 @@ static int is_pcidev_in_array(libxl_devi
     return 0;
 }
 
+/* Write the standard BDF into the sysfs path given by sysfs_path. */
+static int sysfs_write_bdf(libxl__gc *gc, const char * sysfs_path,
+                           libxl_device_pci *pcidev)
+{
+    libxl_ctx *ctx = libxl__gc_owner(gc);
+    int rc, fd;
+    char *buf;
+
+    fd = open(sysfs_path, O_WRONLY);
+    if (fd < 0) {
+        LIBXL__LOG_ERRNO(ctx, LIBXL__LOG_ERROR, "Couldn't open %s",
+                         sysfs_path);
+        return ERROR_FAIL;
+    }
+        
+    buf = libxl__sprintf(gc, PCI_BDF, pcidev->domain, pcidev->bus,
+                         pcidev->dev, pcidev->func);
+    rc = write(fd, buf, strlen(buf));
+    /* Annoying to have two if's, but we need the errno */
+    if (rc < 0)
+        LIBXL__LOG_ERRNO(ctx, LIBXL__LOG_ERROR,
+                         "write to %s returned %d", sysfs_path, rc);
+    close(fd);
+
+    if (rc < 0)
+        return ERROR_FAIL;
+
+    return 0;
+}
+
 libxl_device_pci *libxl_device_pci_list_assignable(libxl_ctx *ctx, int *num)
 {
     GC_INIT(ctx);

@@ -571,27 +601,12 @@ static int do_pci_add(libxl__gc *gc, uin
 
         /* Don't restrict writes to the PCI config space from this VM */
         if (pcidev->permissive) {
-            int fd;
-            char *buf;
-            
-            sysfs_path = libxl__sprintf(gc, SYSFS_PCIBACK_DRIVER"/permissive");
-            fd = open(sysfs_path, O_WRONLY);
-            if (fd < 0) {
-                LIBXL__LOG_ERRNO(ctx, LIBXL__LOG_ERROR, "Couldn't open %s",
-                                 sysfs_path);
+            if ( sysfs_write_bdf(gc, SYSFS_PCIBACK_DRIVER"/permissive",
+                                 pcidev) < 0 ) {
+                LIBXL__LOG(ctx, LIBXL__LOG_ERROR,
+                           "Setting permissive for device");
                 return ERROR_FAIL;
             }
- 
-            buf = libxl__sprintf(gc, PCI_BDF, pcidev->domain, pcidev->bus,
-                                 pcidev->dev, pcidev->func);
-            rc = write(fd, buf, strlen(buf));
-            /* Annoying to have two if's, but we need the errno */
-            if (rc < 0)
-                LIBXL__LOG_ERRNO(ctx, LIBXL__LOG_ERROR,
-                                 "write to %s returned %d", sysfs_path, rc);
-            close(fd);
-            if (rc < 0)
-                return ERROR_FAIL;
         }
         break;
     }

diff -r a2b528299c12 -r 62e682bdb103 tools/libxl/libxl.h
@@ -722,7 +722,7 @@ libxl_device_pci *libxl_device_pci_list(
  * could be assigned to a domain (i.e. are bound to the backend
  * driver) but are not currently.
  */
-libxl_device_pci *libxl_device_pci_list_assignable(libxl_ctx *ctx, int *num);
+libxl_device_pci *libxl_device_pci_assignable_list(libxl_ctx *ctx, int *num);
 
 /* CPUID handling */
 int libxl_cpuid_parse_config(libxl_cpuid_policy_list *cpuid, const char* str);

diff -r a2b528299c12 -r 62e682bdb103 tools/libxl/libxl_pci.c
@@ -357,7 +357,7 @@ static int sysfs_write_bdf(libxl__gc *gc
     return 0;
 }
 
-libxl_device_pci *libxl_device_pci_list_assignable(libxl_ctx *ctx, int *num)
+libxl_device_pci *libxl_device_pci_assignable_list(libxl_ctx *ctx, int *num)
 {
     GC_INIT(ctx);
     libxl_device_pci *pcidevs = NULL, *new, *assigned;

@@ -684,7 +684,7 @@ static int libxl_pcidev_assignable(libxl
     libxl_device_pci *pcidevs;
     int num, i;
 
-    pcidevs = libxl_device_pci_list_assignable(ctx, &num);
+    pcidevs = libxl_device_pci_assignable_list(ctx, &num);
     for (i = 0; i < num; i++) {
         if (pcidevs[i].domain == pcidev->domain &&
             pcidevs[i].bus == pcidev->bus &&

diff -r a2b528299c12 -r 62e682bdb103 tools/libxl/xl.h
@@ -35,9 +35,9 @@ int main_cd_insert(int argc, char **argv
 int main_console(int argc, char **argv);
 int main_vncviewer(int argc, char **argv);
 int main_pcilist(int argc, char **argv);
-int main_pcilist_assignable(int argc, char **argv);
 int main_pcidetach(int argc, char **argv);
 int main_pciattach(int argc, char **argv);
+int main_pciassignable_list(int argc, char **argv);
 int main_restore(int argc, char **argv);
 int main_migrate_receive(int argc, char **argv);
 int main_save(int argc, char **argv);

68 lines not on this page · raw message

diff -r a2b528299c12 -r 62e682bdb103 tools/libxl/xl_cmdtable.c
@@ -86,8 +86,8 @@ struct cmd_spec cmd_table[] = {
       "List pass-through pci devices for a domain",
       "<Domain>",
     },
-    { "pci-list-assignable-devices",
-      &main_pcilist_assignable, 0, 0,
+    { "pci-assignable-list",
+      &main_pciassignable_list, 0, 0,
       "List all the assignable pci devices",
       "",
     },

diff -r a2b528299c12 -r 62e682bdb103 tools/python/xen/lowlevel/xl/xl.c
@@ -566,13 +566,13 @@ static PyObject *pyxl_pci_parse(XlObject
     return (PyObject *)pci;
 }
 
-static PyObject *pyxl_pci_list_assignable(XlObject *self, PyObject *args)
+static PyObject *pyxl_pci_assignable_list(XlObject *self, PyObject *args)
 {
     libxl_device_pci *dev;
     PyObject *list;
     int nr_dev, i;
 
-    dev = libxl_device_pci_list_assignable(self->ctx, &nr_dev);
+    dev = libxl_device_pci_assignable_list(self->ctx, &nr_dev);
     if ( dev == NULL ) {
         PyErr_SetString(xl_error_obj, "Cannot list assignable devices");
         return NULL;

@@ -662,8 +662,8 @@ static PyMethodDef pyxl_methods[] = {
          "Parse pass-through PCI device spec (BDF)"},
     {"device_pci_list", (PyCFunction)pyxl_pci_list, METH_VARARGS,
         "List PCI devices assigned to a domain"},
-    {"device_pci_list_assignable",
-        (PyCFunction)pyxl_pci_list_assignable, METH_NOARGS,
+    {"device_pci_assignable_list",
+        (PyCFunction)pyxl_pci_assignable_list, METH_NOARGS,
         "List assignable PCI devices"},
     { NULL, NULL, 0, NULL }
 };

diff -r 62e682bdb103 -r d6739b5dfd9a tools/libxl/libxl.h
@@ -718,10 +718,29 @@ int libxl_device_pci_destroy(libxl_ctx *
 libxl_device_pci *libxl_device_pci_list(libxl_ctx *ctx, uint32_t domid, int *num);
 
 /*
- * Similar to libxl_device_pci_list but returns all devices which
- * could be assigned to a domain (i.e. are bound to the backend
- * driver) but are not currently.
+ * Functions related to making devices assignable -- that is, bound to
+ * the pciback driver, ready to be given to a guest via
+ * libxl_pci_device_add.
+ *
+ * - ..._add() will unbind the device from its current driver (if
+ * already bound) and re-bind it to pciback; at that point it will be
+ * ready to be assigned to a VM.  If rebind is set, it will store the
+ * path to the old driver in xenstore so that it can be handed back to
+ * dom0 on restore.
+ *
+ * - ..._remove() will unbind the device from pciback, and if
+ * rebind is non-zero, attempt to assign it back to the driver
+ * from whence it came.
+ *
+ * - ..._list() will return a list of the PCI devices available to be
+ * assigned.
+ *
+ * add and remove are idempotent: if the device in question is already
+ * added or is not bound, the functions will emit a warning but return
+ * SUCCESS.
  */
+int libxl_device_pci_assignable_add(libxl_ctx *ctx, libxl_device_pci *pcidev, int rebind);
+int libxl_device_pci_assignable_remove(libxl_ctx *ctx, libxl_device_pci *pcidev, int rebind);
 libxl_device_pci *libxl_device_pci_assignable_list(libxl_ctx *ctx, int *num);
 
 /* CPUID handling */

341 lines not on this page · raw message

diff -r d6739b5dfd9a -r 34a8cded4b39 tools/libxl/xl.h
@@ -37,6 +37,8 @@ int main_vncviewer(int argc, char **argv
 int main_pcilist(int argc, char **argv);
 int main_pcidetach(int argc, char **argv);
 int main_pciattach(int argc, char **argv);
+int main_pciassignable_add(int argc, char **argv);
+int main_pciassignable_remove(int argc, char **argv);
 int main_pciassignable_list(int argc, char **argv);
 int main_restore(int argc, char **argv);
 int main_migrate_receive(int argc, char **argv);

86 lines not on this page · raw message

diff -r d6739b5dfd9a -r 34a8cded4b39 tools/libxl/xl_cmdtable.c
@@ -86,6 +86,20 @@ struct cmd_spec cmd_table[] = {
       "List pass-through pci devices for a domain",
       "<Domain>",
     },
+    { "pci-assignable-add",
+      &main_pciassignable_add, 0, 1,
+      "Make a device assignable for pci-passthru",
+      "<BDF>",
+      "-h                      Print this help.\n"
+    },
+    { "pci-assignable-remove",
+      &main_pciassignable_remove, 0, 1,
+      "Remove a device from being assignable",
+      "[options] <BDF>",
+      "-h                      Print this help.\n"
+      "-r                      Attempt to re-assign the device to the\n"
+      "                        original driver"
+    },
     { "pci-assignable-list",
       &main_pciassignable_list, 0, 0,
       "List all the assignable pci devices",