[v4,8/9] tools: add example application to initialize dom0less PV drivers

Message ID	20220401003847.38393-8-sstabellini@kernel.org (mailing list archive)
State	Superseded
Headers	show Return-Path: <xen-devel-bounces@lists.xenproject.org> Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" <xen-devel-bounces@lists.xenproject.org> From: Stefano Stabellini <sstabellini@kernel.org> To: xen-devel@lists.xenproject.org Cc: sstabellini@kernel.org, jgross@suse.com, Bertrand.Marquis@arm.com, julien@xen.org, Volodymyr_Babchuk@epam.com, Luca Miccio <lucmiccio@gmail.com>, Stefano Stabellini <stefano.stabellini@xilinx.com>, Wei Liu <wl@xen.org>, Anthony PERARD <anthony.perard@citrix.com> Subject: [PATCH v4 8/9] tools: add example application to initialize dom0less PV drivers Date: Thu, 31 Mar 2022 17:38:46 -0700 Message-Id: <20220401003847.38393-8-sstabellini@kernel.org> In-Reply-To: <alpine.DEB.2.22.394.2203311735380.2910984@ubuntu-linux-20-04-desktop> References: <alpine.DEB.2.22.394.2203311735380.2910984@ubuntu-linux-20-04-desktop> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit
Series	dom0less PV drivers \| expand [v4,0/9] dom0less PV drivers [v4,1/9] xen/dt: dt_property_read_string should return -ENODATA on !length [v4,2/9] xen/arm: implement domU extended regions [v4,3/9] xen/arm: temporarily elevate idle_domain privileged during create_domUs [v4,4/9] xen: export evtchn_alloc_unbound [v4,5/9] xen: introduce xen,enhanced dom0less property [v4,6/9] xen/arm: configure dom0less domain for enabling xenstore after boot [v4,7/9] xenstored: send an evtchn notification on introduce_domain [v4,8/9] tools: add example application to initialize dom0less PV drivers [v4,9/9] docs: document dom0less + PV drivers

diff --git a/tools/helpers/Makefile b/tools/helpers/Makefile index 7f6c422440..8e42997052 100644 --- a/tools/helpers/Makefile +++ b/tools/helpers/Makefile @@ -10,6 +10,9 @@ ifeq ($(CONFIG_Linux),y) ifeq ($(CONFIG_X86),y) PROGS += init-xenstore-domain endif +ifeq ($(CONFIG_ARM),y) +PROGS += init-dom0less +endif endif XEN_INIT_DOM0_OBJS = xen-init-dom0.o init-dom-json.o @@ -26,6 +29,13 @@ $(INIT_XENSTORE_DOMAIN_OBJS): CFLAGS += $(CFLAGS_libxenstore) $(INIT_XENSTORE_DOMAIN_OBJS): CFLAGS += $(CFLAGS_libxenlight) $(INIT_XENSTORE_DOMAIN_OBJS): CFLAGS += -include $(XEN_ROOT)/tools/config.h +INIT_DOM0LESS_OBJS = init-dom0less.o init-dom-json.o +$(INIT_DOM0LESS_OBJS): CFLAGS += $(CFLAGS_libxentoollog) +$(INIT_DOM0LESS_OBJS): CFLAGS += $(CFLAGS_libxenstore) +$(INIT_DOM0LESS_OBJS): CFLAGS += $(CFLAGS_libxenlight) +$(INIT_DOM0LESS_OBJS): CFLAGS += $(CFLAGS_libxenctrl) +$(INIT_DOM0LESS_OBJS): CFLAGS += $(CFLAGS_libxenevtchn) + .PHONY: all all: $(PROGS) @@ -35,6 +45,9 @@ xen-init-dom0: $(XEN_INIT_DOM0_OBJS) init-xenstore-domain: $(INIT_XENSTORE_DOMAIN_OBJS) $(CC) $(LDFLAGS) -o $@ $(INIT_XENSTORE_DOMAIN_OBJS) $(LDLIBS_libxentoollog) $(LDLIBS_libxenstore) $(LDLIBS_libxenctrl) $(LDLIBS_libxenguest) $(LDLIBS_libxenlight) $(APPEND_LDFLAGS) +init-dom0less: $(INIT_DOM0LESS_OBJS) + $(CC) $(LDFLAGS) -o $@ $(INIT_DOM0LESS_OBJS) $(LDLIBS_libxenctrl) $(LDLIBS_libxenevtchn) $(LDLIBS_libxentoollog) $(LDLIBS_libxenstore) $(LDLIBS_libxenlight) $(LDLIBS_libxenguest) $(APPEND_LDFLAGS) + .PHONY: install install: all $(INSTALL_DIR) $(DESTDIR)$(LIBEXEC_BIN) diff --git a/tools/helpers/init-dom0less.c b/tools/helpers/init-dom0less.c new file mode 100644 index 0000000000..dc9ccee868 --- /dev/null +++ b/tools/helpers/init-dom0less.c @@ -0,0 +1,323 @@ +#include <stdbool.h> +#include <syslog.h> +#include <stdio.h> +#include <err.h> +#include <stdlib.h> +#include <sys/time.h> +#include <xenstore.h> +#include <xenctrl.h> +#include <xenguest.h> +#include <libxl.h> +#include <xenevtchn.h> + +#include "init-dom-json.h" + +#define XENSTORE_PFN_OFFSET 1 +#define STR_MAX_LENGTH 64 + +static int alloc_xs_page(struct xc_interface_core *xch, + libxl_dominfo *info, + uint64_t *xenstore_pfn) +{ + int rc; + const xen_pfn_t base = GUEST_MAGIC_BASE >> XC_PAGE_SHIFT; + xen_pfn_t p2m = (GUEST_MAGIC_BASE >> XC_PAGE_SHIFT) + XENSTORE_PFN_OFFSET; + + rc = xc_domain_setmaxmem(xch, info->domid, + info->max_memkb + (XC_PAGE_SIZE/1024)); + if (rc < 0) + return rc; + + rc = xc_domain_populate_physmap_exact(xch, info->domid, 1, 0, 0, &p2m); + if (rc < 0) + return rc; + + *xenstore_pfn = base + XENSTORE_PFN_OFFSET; + rc = xc_clear_domain_page(xch, info->domid, *xenstore_pfn); + if (rc < 0) + return rc; + + return 0; +} + +static bool do_xs_write_dom(struct xs_handle *xsh, xs_transaction_t t, + domid_t domid, char *path, char *val) +{ + char full_path[STR_MAX_LENGTH]; + struct xs_permissions perms[2]; + + perms[0].id = domid; + perms[0].perms = XS_PERM_NONE; + perms[1].id = 0; + perms[1].perms = XS_PERM_READ; + + if (snprintf(full_path, STR_MAX_LENGTH, + "/local/domain/%u/%s", domid, path) < 0) + return false; + if (!xs_write(xsh, t, full_path, val, strlen(val))) + return false; + return xs_set_permissions(xsh, t, full_path, perms, 2); +} + +static bool do_xs_write_libxl(struct xs_handle *xsh, xs_transaction_t t, + domid_t domid, char *path, char *val) +{ + char full_path[STR_MAX_LENGTH]; + + if (snprintf(full_path, STR_MAX_LENGTH, + "/libxl/%u/%s", domid, path) < 0) + return false; + return xs_write(xsh, t, full_path, val, strlen(val)); +} + +static bool do_xs_write_vm(struct xs_handle *xsh, xs_transaction_t t, + libxl_uuid uuid, char *path, char *val) +{ + char full_path[STR_MAX_LENGTH]; + + if (snprintf(full_path, STR_MAX_LENGTH, + "/vm/" LIBXL_UUID_FMT "/%s", LIBXL_UUID_BYTES(uuid), path) < 0) + return false; + return xs_write(xsh, t, full_path, val, strlen(val)); +} + +/* + * The xenstore nodes are the xenstore nodes libxl writes at domain + * creation. + * + * The list was retrieved by running xenstore-ls on a corresponding + * domain started by xl/libxl. + */ +static int create_xenstore(struct xs_handle *xsh, + libxl_dominfo *info, libxl_uuid uuid, + evtchn_port_t xenstore_port) +{ + domid_t domid; + unsigned int i; + char uuid_str[STR_MAX_LENGTH]; + char dom_name_str[STR_MAX_LENGTH]; + char vm_val_str[STR_MAX_LENGTH]; + char id_str[STR_MAX_LENGTH]; + char max_memkb_str[STR_MAX_LENGTH]; + char target_memkb_str[STR_MAX_LENGTH]; + char cpu_str[STR_MAX_LENGTH]; + char xenstore_port_str[STR_MAX_LENGTH]; + char ring_ref_str[STR_MAX_LENGTH]; + xs_transaction_t t; + struct timeval start_time; + char start_time_str[STR_MAX_LENGTH]; + int rc; + + if (gettimeofday(&start_time, NULL) < 0) + return -errno; + rc = snprintf(start_time_str, STR_MAX_LENGTH, "%jd.%02d", + (intmax_t)start_time.tv_sec, (int)start_time.tv_usec / 10000); + if (rc < 0) + return rc; + + domid = info->domid; + rc = snprintf(id_str, STR_MAX_LENGTH, "%u", domid); + if (rc < 0) + return rc; + rc = snprintf(dom_name_str, STR_MAX_LENGTH, "dom0less-%u", domid); + if (rc < 0) + return rc; + rc = snprintf(uuid_str, STR_MAX_LENGTH, LIBXL_UUID_FMT, LIBXL_UUID_BYTES(uuid)); + if (rc < 0) + return rc; + rc = snprintf(vm_val_str, STR_MAX_LENGTH, + "vm/" LIBXL_UUID_FMT, LIBXL_UUID_BYTES(uuid)); + if (rc < 0) + return rc; + rc = snprintf(max_memkb_str, STR_MAX_LENGTH, "%lu", info->max_memkb); + if (rc < 0) + return rc; + rc = snprintf(target_memkb_str, STR_MAX_LENGTH, "%lu", info->current_memkb); + if (rc < 0) + return rc; + rc = snprintf(ring_ref_str, STR_MAX_LENGTH, "%lld", + (GUEST_MAGIC_BASE >> XC_PAGE_SHIFT) + XENSTORE_PFN_OFFSET); + if (rc < 0) + return rc; + rc = snprintf(xenstore_port_str, STR_MAX_LENGTH, "%u", xenstore_port); + if (rc < 0) + return rc; + +retry_transaction: + t = xs_transaction_start(xsh); + if (t == XBT_NULL) + return -errno; + + rc = -EIO; + /* /vm */ + if (!do_xs_write_vm(xsh, t, uuid, "name", dom_name_str)) goto err; + if (!do_xs_write_vm(xsh, t, uuid, "uuid", uuid_str)) goto err; + if (!do_xs_write_vm(xsh, t, uuid, "start_time", start_time_str)) goto err; + + /* /domain */ + if (!do_xs_write_dom(xsh, t, domid, "vm", vm_val_str)) goto err; + if (!do_xs_write_dom(xsh, t, domid, "name", dom_name_str)) goto err; + if (!do_xs_write_dom(xsh, t, domid, "cpu", "")) goto err; + for (i = 0; i < info->vcpu_max_id; i++) { + rc = snprintf(cpu_str, STR_MAX_LENGTH, "cpu/%u/availability/", i); + if (rc < 0) + goto err; + rc = -EIO; + if (!do_xs_write_dom(xsh, t, domid, cpu_str, + (info->cpupool & (1 << i)) ? "online" : "offline")) + goto err; + } + + if (!do_xs_write_dom(xsh, t, domid, "memory", "")) goto err; + if (!do_xs_write_dom(xsh, t, domid, "memory/static-max", max_memkb_str)) goto err; + if (!do_xs_write_dom(xsh, t, domid, "memory/target", target_memkb_str)) goto err; + if (!do_xs_write_dom(xsh, t, domid, "memory/videoram", "-1")) goto err; + + if (!do_xs_write_dom(xsh, t, domid, "device", "")) goto err; + if (!do_xs_write_dom(xsh, t, domid, "device/suspend", "")) goto err; + if (!do_xs_write_dom(xsh, t, domid, "device/suspend/event-channel", "")) goto err; + + if (!do_xs_write_dom(xsh, t, domid, "control", "")) goto err; + if (!do_xs_write_dom(xsh, t, domid, "control/shutdown", "")) goto err; + if (!do_xs_write_dom(xsh, t, domid, "control/feature-poweroff", "1")) goto err; + if (!do_xs_write_dom(xsh, t, domid, "control/feature-reboot", "1")) goto err; + if (!do_xs_write_dom(xsh, t, domid, "control/feature-suspend", "")) goto err; + if (!do_xs_write_dom(xsh, t, domid, "control/sysrq", "")) goto err; + if (!do_xs_write_dom(xsh, t, domid, "control/platform-feature-multiprocessor-suspend", "1")) goto err; + if (!do_xs_write_dom(xsh, t, domid, "control/platform-feature-xs_reset_watches", "1")) goto err; + + if (!do_xs_write_dom(xsh, t, domid, "domid", id_str)) goto err; + if (!do_xs_write_dom(xsh, t, domid, "data", "")) goto err; + if (!do_xs_write_dom(xsh, t, domid, "drivers", "")) goto err; + if (!do_xs_write_dom(xsh, t, domid, "feature", "")) goto err; + if (!do_xs_write_dom(xsh, t, domid, "attr", "")) goto err; + + if (!do_xs_write_dom(xsh, t, domid, "store/port", xenstore_port_str)) goto err; + if (!do_xs_write_dom(xsh, t, domid, "store/ring-ref", ring_ref_str)) goto err; + + if (!do_xs_write_libxl(xsh, t, domid, "type", "pvh")) goto err; + if (!do_xs_write_libxl(xsh, t, domid, "dm-version", "qemu_xen")) goto err; + + if (!xs_transaction_end(xsh, t, false)) { + if (errno == EAGAIN) + goto retry_transaction; + else + return -errno; + } + + return 0; + +err: + xs_transaction_end(xsh, t, true); + return rc; +} + +static int init_domain(struct xs_handle *xsh, libxl_dominfo *info) +{ + struct xc_interface_core *xch; + libxl_uuid uuid; + uint64_t xenstore_evtchn, xenstore_pfn; + int rc; + + printf("Init dom0less domain: %u\n", info->domid); + xch = xc_interface_open(0, 0, 0); + + rc = xc_hvm_param_get(xch, info->domid, HVM_PARAM_STORE_EVTCHN, + &xenstore_evtchn); + if (rc != 0) { + printf("Failed to get HVM_PARAM_STORE_EVTCHN\n"); + return 1; + } + + /* Alloc xenstore page */ + if (alloc_xs_page(xch, info, &xenstore_pfn) != 0) { + printf("Error on alloc magic pages\n"); + return 1; + } + + rc = xc_dom_gnttab_seed(xch, info->domid, true, + (xen_pfn_t)-1, xenstore_pfn, 0, 0); + if (rc) + err(1, "xc_dom_gnttab_seed"); + + libxl_uuid_generate(&uuid); + xc_domain_sethandle(xch, info->domid, libxl_uuid_bytearray(&uuid)); + + rc = gen_stub_json_config(info->domid, &uuid); + if (rc) + err(1, "gen_stub_json_config"); + + /* Now everything is ready: set HVM_PARAM_STORE_PFN */ + rc = xc_hvm_param_set(xch, info->domid, HVM_PARAM_STORE_PFN, + xenstore_pfn); + if (rc < 0) + return rc; + + rc = create_xenstore(xsh, info, uuid, xenstore_evtchn); + if (rc) + err(1, "writing to xenstore"); + + rc = xs_introduce_domain(xsh, info->domid, + (GUEST_MAGIC_BASE >> XC_PAGE_SHIFT) + XENSTORE_PFN_OFFSET, + xenstore_evtchn); + if (!rc) + err(1, "xs_introduce_domain"); + return 0; +} + +/* Check if domain has been configured in XS */ +static bool domain_exists(struct xs_handle *xsh, int domid) +{ + return xs_is_domain_introduced(xsh, domid); +} + +int main(int argc, char **argv) +{ + libxl_dominfo *info = NULL; + libxl_ctx *ctx; + int nb_vm = 0, rc = 0, i; + struct xs_handle *xsh = NULL; + + /* TODO reuse libxl xsh connection */ + xsh = xs_open(0); + if (xsh == NULL) { + fprintf(stderr, "Could not contact XenStore"); + rc = -errno; + goto out; + } + + rc = libxl_ctx_alloc(&ctx, LIBXL_VERSION, 0, NULL); + if (rc) { + fprintf(stderr, "cannot init xl context\n"); + goto out; + } + + info = libxl_list_domain(ctx, &nb_vm); + if (!info) { + fprintf(stderr, "libxl_list_vm failed.\n"); + rc = -1; + goto out; + } + + for (i = 0; i < nb_vm; i++) { + domid_t domid = info[i].domid; + + /* Don't need to check for Dom0 */ + if (!domid) + continue; + + printf("Checking domid: %u\n", domid); + if (!domain_exists(xsh, domid)) { + rc = init_domain(xsh, &info[i]); + if (rc < 0) { + fprintf(stderr, "init_domain failed.\n"); + goto out; + } + } else { + printf("Domain %u has already been initialized\n", domid); + } + } +out: + libxl_dominfo_list_free(info, nb_vm); + return rc; +}

[v4,8/9] tools: add example application to initialize dom0less PV drivers

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