On Thu, Mar 05, 2026 at 02:52:05PM +0100, Juergen Gross wrote:
diff --git a/tools/include/libxl.h b/tools/include/libxl.h
index bc35e412da..a70d9d347f 100644
--- a/tools/include/libxl.h
+++ b/tools/include/libxl.h
@@ -1537,6 +1537,18 @@ void libxl_mac_copy(libxl_ctx *ctx, libxl_mac *dst,
const libxl_mac *src);
*/
#define LIBXL_HAVE_XEN_PLATFORM_PCI_BAR_UC
+/*
+ * LIBXL_HAVE_XENSTORE_QUOTA
+ *
+ * If this is defined the Xenstore quota related functions
+ * libxl_xsquota_global_get()
+ * libxl_xsquota_global_set()
+ * libxl_xsquota_domain_get()
+ * libxl_xsquota_domain_set()
+ * are available.
+ */
+#define LIBXL_HAVE_XENSTORE_QUOTA
+
typedef char **libxl_string_list;
void libxl_string_list_dispose(libxl_string_list *sl);
int libxl_string_list_length(const libxl_string_list *sl);
@@ -3011,6 +3023,14 @@ static inline int
libxl_qemu_monitor_command_0x041200(libxl_ctx *ctx,
#define libxl_qemu_monitor_command libxl_qemu_monitor_command_0x041200
#endif
+/* Get/set global and per-domain Xenstore quota. */
+int libxl_xsquota_global_get(libxl_ctx *ctx, libxl_xs_quota_set *q);
Could you rename the second arg as "q_r" or "q_out" ?
+int libxl_xsquota_global_set(libxl_ctx *ctx, libxl_xs_quota_set *q);
+int libxl_xsquota_domain_get(libxl_ctx *ctx, uint32_t domid,
+ libxl_xs_quota_set *q);
Same here.
+int libxl_xsquota_domain_set(libxl_ctx *ctx, uint32_t domid,
+ libxl_xs_quota_set *q);
Could we prefix them all with "libxl_xs_quota_" ? I would rather that we
only use "xs_quota" or "xsquota".
+
#include <libxl_event.h>
/*
diff --git a/tools/libs/light/Makefile b/tools/libs/light/Makefile
index bc60c46558..ca22a40c6c 100644
--- a/tools/libs/light/Makefile
+++ b/tools/libs/light/Makefile
@@ -106,6 +106,7 @@ OBJS-y += libxl_pvcalls.o
OBJS-y += libxl_vsnd.o
OBJS-y += libxl_vkb.o
OBJS-y += libxl_virtio.o
+OBJS-y += libxl_xsquota.o
OBJS-y += libxl_genid.o
OBJS-y += _libxl_types.o
OBJS-y += libxl_flask.o
diff --git a/tools/libs/light/libxl_types.idl b/tools/libs/light/libxl_types.idl
index d64a573ff3..c5ddc40f35 100644
--- a/tools/libs/light/libxl_types.idl
+++ b/tools/libs/light/libxl_types.idl
@@ -574,6 +574,15 @@ libxl_altp2m_mode = Enumeration("altp2m_mode", [
(3, "limited"),
], init_val = "LIBXL_ALTP2M_MODE_DISABLED")
+libxl_xs_quota_item = Struct("xs_quota_item", [
+ ("name", string),
+ ("val", uint32),
+ ])
+
+libxl_xs_quota_set = Struct("xs_quota_set", [
Could you use "_list" as a suffix instead? It's a bit confusing to have
the word "set" as a double meaning, with a _set() function that takes a
set.
+ ("quota", Array(libxl_xs_quota_item, "num_quota"))
+ ])
+
libxl_domain_build_info = Struct("domain_build_info",[
("max_vcpus", integer),
("avail_vcpus", libxl_bitmap),
diff --git a/tools/libs/light/libxl_xsquota.c b/tools/libs/light/libxl_xsquota.c
new file mode 100644
index 0000000000..b9afa1c914
--- /dev/null
+++ b/tools/libs/light/libxl_xsquota.c
@@ -0,0 +1,102 @@
+/* SPDX-License-Identifier: LGPL-2.1-only */
+
+/* Xenstore quota handling functions. */
+
+#include "libxl_internal.h"
+
+static int get_quota(libxl_ctx *ctx, unsigned int domid, libxl_xs_quota_set *q,
+ bool (func)(struct xs_handle *h, unsigned int domid,
+ char *quota, unsigned int *value))
+{
+ char **names;
+ unsigned int num, i;
+ int rc = 0;
We don't init `rc` variable in libxl function. Set `rc` to 0 just before
the "out" label.
+ GC_INIT(ctx);
+
+ names = xs_get_quota_names(ctx->xsh, &num);
+ if (!names) {
+ /* Xenstore quota support is optional! */
+ if (errno != ENOSYS)
+ rc = ERROR_FAIL;
+ q->num_quota = 0;
It feels wrong to make changes to the output argument on error, if we
can avoid it. And here, I don't see any reason to change `q`.
+ goto out;
+ }
+
Can you call libxl_xs_quota_set_init() first? As you call _dispose()
later.
+ q->num_quota = num;
+ q->quota = libxl__calloc(NOGC, num, sizeof(*q->quota));
+ for (i = 0; i < num; i++) {
+ q->quota[i].name = libxl__strdup(NOGC, names[i]);
+ if (!func(ctx->xsh, domid, q->quota[i].name, &q->quota[i].val)) {
Could you store the return value of `func()` in `ok`, and test `ok` in the
if instead?
+ libxl_xs_quota_set_dispose(q);
+ rc = ERROR_FAIL;
+ break;
This can be `goto out` once free(names) is moved to the out label.
+ }
+ }
+
+ free(names);
Could you do that after the "out" label? And init `names` to NULL.
+
+ out:
+ GC_FREE;
+ return rc;
+}
+
+static int set_quota(libxl_ctx *ctx, unsigned int domid, libxl_xs_quota_set *q,
+ bool (func)(struct xs_handle *h, unsigned int domid,
+ char *quota, unsigned int value))
+{
+ unsigned int i;
+ int rc = 0;
+ GC_INIT(ctx);
+
+ for (i = 0; i < q->num_quota; i++) {
+ if (!func(ctx->xsh, domid, q->quota[i].name, q->quota[i].val)) {
+ rc = ERROR_FAIL;
+ break;
It would be better to write `goto out` instead.
+ }
+ }
+
+ GC_FREE;
+ return rc;
+}
