Refactor libxl device destroy code. Abstract function
waiting for the watch on the state node to fire.
Create a generic device delete function.
Only a single LIBXL_DESTROY_TIMEOUT elapses when
waiting for destruction of all the devices of a
domain.
Signed-off-by: Andres Lagar-Cavilla <andres@xxxxxxxxxxxxxxxx>
# HG changeset patch
# User Andres Lagar-Cavilla <andres@xxxxxxxxxxxxxxxx>
# Date 1259848362 18000
# Node ID ff941d6ded127d8d0bb6e754654140d9e1dfb0b1
# Parent eeb2f35cd9a7a5a6c4e38c1ec5995524035375fa
Refactor libxl device destroy code. Abstract function
waiting for the watch on the state node to fire.
Create a generic device delete function.
Only a single LIBXL_DESTROY_TIMEOUT elapses when
waiting for destruction of all the devices of a
domain.
Signed-off-by: Andres Lagar-Cavilla <andres@xxxxxxxxxxxxxxxx>
diff -r eeb2f35cd9a7 -r ff941d6ded12 libxl_device.c
--- a/libxl_device.c
+++ b/libxl_device.c
@@ -203,14 +203,40 @@ retry_transaction:
return 0;
}
+int wait_for_dev_destroy(struct libxl_ctx *ctx, struct timeval *tv)
+{
+ int nfds, rc;
+ unsigned int n;
+ fd_set rfds;
+ char **l1 = NULL;
+
+ rc = 1;
+ nfds = xs_fileno(ctx->xsh) + 1;
+ FD_ZERO(&rfds);
+ FD_SET(xs_fileno(ctx->xsh), &rfds);
+ if (select(nfds, &rfds, NULL, NULL, tv) > 0) {
+ l1 = xs_read_watch(ctx->xsh, &n);
+ if (l1 != NULL) {
+ char *state = libxl_xs_read(ctx, XBT_NULL, l1[XS_WATCH_PATH]);
+ if (!state || atoi(state) == 6) {
+ xs_unwatch(ctx->xsh, l1[0], l1[1]);
+ xs_rm(ctx->xsh, XBT_NULL, l1[XS_WATCH_TOKEN]);
+ XL_LOG(ctx, XL_LOG_DEBUG, "Destroyed device backend at %s",
l1[XS_WATCH_TOKEN]);
+ rc = 0;
+ }
+ libxl_free(ctx, state);
+ free(l1);
+ }
+ }
+ return rc;
+}
+
int libxl_devices_destroy(struct libxl_ctx *ctx, uint32_t domid, int force)
{
char *path, *be_path, *fe_path;
unsigned int num1, num2;
char **l1 = NULL, **l2 = NULL;
- int i, j, nfds, n = 0, n_watches = 0;
- fd_set rfds;
- struct timeval tv;
+ int i, j, n = 0, n_watches = 0;
flexarray_t *toremove;
struct libxl_ctx clone;
@@ -245,27 +271,20 @@ int libxl_devices_destroy(struct libxl_c
}
}
if (!force) {
- nfds = xs_fileno(clone.xsh) + 1;
- /* Linux-ism */
+ /* Linux-ism. Most implementations leave the timeout
+ * untouched after select. Linux, however, will chip
+ * away the elapsed time from it, which is what we
+ * need to enforce a single time span waiting for
+ * device destruction. */
+ struct timeval tv;
tv.tv_sec = LIBXL_DESTROY_TIMEOUT;
tv.tv_usec = 0;
- while (n_watches > 0 && tv.tv_sec > 0) {
- FD_ZERO(&rfds);
- FD_SET(xs_fileno(clone.xsh), &rfds);
- if (select(nfds, &rfds, NULL, NULL, &tv) > 0) {
- l1 = xs_read_watch(clone.xsh, &num1);
- if (l1 != NULL) {
- char *state = libxl_xs_read(&clone, XBT_NULL, l1[0]);
- if (!state || atoi(state) == 6) {
- xs_unwatch(clone.xsh, l1[0], l1[1]);
- xs_rm(clone.xsh, XBT_NULL, l1[1]);
- XL_LOG(&clone, XL_LOG_DEBUG, "Destroyed device backend
at %s", l1[1]);
- n_watches--;
- }
- free(l1);
- }
- } else
+ while (n_watches > 0) {
+ if (wait_for_dev_destroy(&clone, &tv)) {
break;
+ } else {
+ n_watches--;
+ }
}
}
for (i = 0; i < n; i++) {
@@ -277,6 +296,49 @@ int libxl_devices_destroy(struct libxl_c
return 0;
}
+int libxl_device_del(struct libxl_ctx *ctx, libxl_device *dev, int wait)
+{
+ char *dom_path_backend, *backend_path, *hotplug_path;
+ int rc;
+ struct libxl_ctx clone;
+
+ if (libxl_clone_context_xs(ctx, &clone)) {
+ XL_LOG(ctx, XL_LOG_ERROR, "Out of memory when cloning context");
+ return ERROR_NOMEM;
+ }
+
+ /* Create strings */
+ dom_path_backend = libxl_xs_get_dompath(&clone, dev->backend_domid);
+ backend_path = libxl_sprintf(&clone, "%s/backend/%s/%u/%d",
+ dom_path_backend,
+ string_of_kinds[dev->backend_kind],
+ dev->domid, dev->devid);
+ hotplug_path = libxl_sprintf(&clone, "/xapi/%d/hotplug/%s/%d",
+ dev->domid,
+ string_of_kinds[dev->kind],
+ dev->devid);
+ libxl_free(&clone, dom_path_backend);
+
+ rc = libxl_device_destroy(&clone, backend_path, !wait);
+ if (rc == -1) {
+ libxl_discard_cloned_context_xs(&clone);
+ return ERROR_FAIL;
+ }
+
+ if (wait) {
+ struct timeval tv;
+ tv.tv_sec = LIBXL_DESTROY_TIMEOUT;
+ tv.tv_usec = 0;
+ (void)wait_for_dev_destroy(&clone, &tv);
+ }
+
+ xs_rm(clone.xsh, XBT_NULL, hotplug_path);
+ libxl_free(&clone, hotplug_path);
+ libxl_free(&clone, backend_path);
+ libxl_discard_cloned_context_xs(&clone);
+ return 0;
+}
+
int libxl_device_pci_flr(struct libxl_ctx *ctx, unsigned int domain, unsigned
int bus,
unsigned int dev, unsigned int func)
{
diff -r eeb2f35cd9a7 -r ff941d6ded12 libxl_internal.h
--- a/libxl_internal.h
+++ b/libxl_internal.h
@@ -124,6 +124,7 @@ int device_disk_dev_number(char *virtpat
int libxl_device_generic_add(struct libxl_ctx *ctx, libxl_device *device,
char **bents, char **fents);
+int libxl_device_del(struct libxl_ctx *ctx, libxl_device *dev, int wait);
int libxl_device_destroy(struct libxl_ctx *ctx, char *be_path, int force);
int libxl_devices_destroy(struct libxl_ctx *ctx, uint32_t domid, int force);
int libxl_wait_for_device_model(struct libxl_ctx *ctx,
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