Stratos-dev June 2021

stratos-dev@op-lists.linaro.org

16 participants
13 discussions

Re: [Stratos-dev] [PATCH 3/5] vhost-user-rng: backend: Add RNG vhost-user daemon implementation

by Joakim Bech

On Tue, Jun 01, 2021 at 08:03:20PM +0000, Mathieu Poirier via Stratos-dev wrote: > This patch provides the vhost-user backend implementation to work > in tandem with the vhost-user-rng implementation of the QEMU VMM. > > It uses the vhost-user API so that other VMM can re-use the interface > without having to write the driver again. > > Signed-off-by: Mathieu Poirier <mathieu.poirier(a)linaro.org> > --- > tools/meson.build | 8 + > tools/vhost-user-rng/50-qemu-rng.json.in | 5 + > tools/vhost-user-rng/main.c | 403 +++++++++++++++++++++++ > tools/vhost-user-rng/meson.build | 10 + > 4 files changed, 426 insertions(+) > create mode 100644 tools/vhost-user-rng/50-qemu-rng.json.in > create mode 100644 tools/vhost-user-rng/main.c > create mode 100644 tools/vhost-user-rng/meson.build > > diff --git a/tools/meson.build b/tools/meson.build > index 3e5a0abfa29f..66b0a11fbb45 100644 > --- a/tools/meson.build > +++ b/tools/meson.build > @@ -24,3 +24,11 @@ endif > if have_virtiofsd > subdir('virtiofsd') > endif > + > +have_virtiorng = (have_system and > + have_tools and > + 'CONFIG_LINUX' in config_host) > + > +if have_virtiorng > + subdir('vhost-user-rng') > +endif > diff --git a/tools/vhost-user-rng/50-qemu-rng.json.in b/tools/vhost-user-rng/50-qemu-rng.json.in > new file mode 100644 > index 000000000000..9186c3c6fe1d > --- /dev/null > +++ b/tools/vhost-user-rng/50-qemu-rng.json.in > @@ -0,0 +1,5 @@ > +{ > + "description": "QEMU vhost-user-rng", > + "type": "bridge", > + "binary": "@libexecdir@/vhost-user-rng" > +} > diff --git a/tools/vhost-user-rng/main.c b/tools/vhost-user-rng/main.c > new file mode 100644 > index 000000000000..ba7380b12659 > --- /dev/null > +++ b/tools/vhost-user-rng/main.c > @@ -0,0 +1,403 @@ > +/* > + * VIRTIO RNG Emulation via vhost-user > + * > + * Copyright (c) 2021 Mathieu Poirier <mathieu.poirier(a)linaro.org> > + * > + * SPDX-License-Identifier: GPL-2.0-or-later > + */ > + > +#define G_LOG_DOMAIN "vhost-user-rng" > +#define G_LOG_USE_STRUCTURED 1 > + > +#include <glib.h> > +#include <gio/gio.h> > +#include <gio/gunixsocketaddress.h> > +#include <glib-unix.h> > +#include <glib/gstdio.h> > +#include <pthread.h> > +#include <signal.h> > +#include <stdio.h> > +#include <stdbool.h> > +#include <string.h> > +#include <inttypes.h> > +#include <fcntl.h> > +#include <sys/ioctl.h> > +#include <sys/types.h> > +#include <sys/stat.h> > +#include <sys/mman.h> > +#include <time.h> > +#include <unistd.h> > +#include <endian.h> > +#include <assert.h> > + > +#include "qemu/cutils.h" > +#include "subprojects/libvhost-user/libvhost-user-glib.h" > +#include "subprojects/libvhost-user/libvhost-user.h" > + > +#ifndef container_of > +#define container_of(ptr, type, member) ({ \ > + const typeof(((type *) 0)->member) * __mptr = (ptr); \ > + (type *) ((char *) __mptr - offsetof(type, member)); }) > +#endif > + > +typedef struct { > + VugDev dev; > + struct itimerspec ts; > + timer_t rate_limit_timer; > + pthread_mutex_t rng_mutex; > + pthread_cond_t rng_cond; > + int64_t quota_remaining; > + bool activate_timer; > + GMainLoop *loop; > +} VuRNG; > + > +static gboolean print_cap, verbose; > +static gchar *source_path, *socket_path; > +static gint source_fd, socket_fd = -1; > + > +/* Defaults tailored on virtio-rng.c */ > +static uint32_t period_ms = 1 << 16; > +static uint64_t max_bytes = INT64_MAX; > + > +static void check_rate_limit(union sigval sv) > +{ > + VuRNG *rng = sv.sival_ptr; > + bool wakeup = false; > + > + pthread_mutex_lock(&rng->rng_mutex); > + /* > + * The timer has expired and the guest has used all available > + * antropy, which means function vu_rng_handle_request() is waiting s/antropy/entropy/ I also found 'antropy' at two more locations in this patch (that made me wonder). > + * on us. As such wake it up once we're done here. > + */ > + if (rng->quota_remaining == 0) { > + wakeup = true; > + } > + > + /* > + * Reset the antropy available to the guest and tell function > + * vu_rng_handle_requests() to start the timer before using it. > + */ > + rng->quota_remaining = max_bytes; > + rng->activate_timer = true; > + pthread_mutex_unlock(&rng->rng_mutex); > + > + if (wakeup) { > + pthread_cond_signal(&rng->rng_cond); > + } > +} > + > +static void setup_timer(VuRNG *rng) > +{ > + struct sigevent sev; > + int ret; > + > + memset(&rng->ts, 0, sizeof(struct itimerspec)); > + rng->ts.it_value.tv_sec = period_ms / 1000; > + rng->ts.it_value.tv_nsec = (period_ms % 1000) * 1000000; > + > + /* > + * Call function check_rate_limit() as if it was the start of > + * a new thread when the timer expires. > + */ > + sev.sigev_notify = SIGEV_THREAD; > + sev.sigev_notify_function = check_rate_limit; > + sev.sigev_value.sival_ptr = rng; > + /* Needs to be NULL if defaults attributes are to be used. */ > + sev.sigev_notify_attributes = NULL; > + ret = timer_create(CLOCK_MONOTONIC, &sev, &rng->rate_limit_timer); > + if (ret < 0) { > + fprintf(stderr, "timer_create() failed\n"); > + } > + > +} > + > + > +/* Virtio helpers */ > +static uint64_t rng_get_features(VuDev *dev) > +{ > + if (verbose) { > + g_info("%s: replying", __func__); > + } > + return 0; > +} > + > +static void rng_set_features(VuDev *dev, uint64_t features) > +{ > + if (verbose && features) { > + g_autoptr(GString) s = g_string_new("Requested un-handled feature"); > + g_string_append_printf(s, " 0x%" PRIx64 "", features); > + g_info("%s: %s", __func__, s->str); > + } > +} > + > +static void vu_rng_handle_requests(VuDev *dev, int qidx) > +{ > + VuRNG *rng = container_of(dev, VuRNG, dev.parent); > + VuVirtq *vq = vu_get_queue(dev, qidx); > + VuVirtqElement *elem; > + size_t to_read; > + int len, ret; > + > + for (;;) { > + /* Get element in the vhost virtqueue */ > + elem = vu_queue_pop(dev, vq, sizeof(VuVirtqElement)); > + if (!elem) { > + break; > + } > + > + /* Get the amount of antropy to read from the vhost server */ > + to_read = elem->in_sg[0].iov_len; > + > + pthread_mutex_lock(&rng->rng_mutex); > + > + /* > + * We have consumed all entropy available for this time slice. > + * Wait for the timer (check_rate_limit()) to tell us about the > + * start of a new time slice. > + */ > + if (rng->quota_remaining == 0) { > + pthread_cond_wait(&rng->rng_cond, &rng->rng_mutex); > + } > + > + /* Start the timer if the last time slice has expired */ > + if (rng->activate_timer == true) { > + rng->activate_timer = false; > + ret = timer_settime(rng->rate_limit_timer, 0, &rng->ts, NULL); > + if (ret < 0) { > + fprintf(stderr, "timer_settime() failed\n"); > + } > + } > + > + /* Make sure we don't read more than it's available */ > + if (rng->quota_remaining < to_read) { > + to_read = rng->quota_remaining; > + } > + > + len = read(source_fd, elem->in_sg[0].iov_base, to_read); > + > + /* Simply return 0 if an error occurs */ > + if (len < 0) { > + len = 0; > + } > + > + rng->quota_remaining -= len; > + > + pthread_mutex_unlock(&rng->rng_mutex); > + > + vu_queue_push(dev, vq, elem, len); > + free(elem); > + } > + > + vu_queue_notify(dev, vq); > +} > + > +static void > +vu_rng_queue_set_started(VuDev *dev, int qidx, bool started) > +{ > + VuVirtq *vq = vu_get_queue(dev, qidx); > + > + g_debug("queue started %d:%d\n", qidx, started); > + > + if (!qidx) { > + vu_set_queue_handler(dev, vq, started ? vu_rng_handle_requests : NULL); > + } > +} > + > +/* > + * Any messages not handled here are processed by the libvhost library > + * itself. > + */ > +static int rng_process_msg(VuDev *dev, VhostUserMsg *msg, int *do_reply) > +{ > + VuRNG *rng = container_of(dev, VuRNG, dev.parent); > + > + if (msg->request == VHOST_USER_NONE) { > + g_main_loop_quit(rng->loop); > + return 1; > + } > + > + return 0; > +} > + > +static const VuDevIface vuiface = { > + .set_features = rng_set_features, > + .get_features = rng_get_features, > + .queue_set_started = vu_rng_queue_set_started, > + .process_msg = rng_process_msg, > +}; > + > +static gboolean hangup(gpointer user_data) > +{ > + GMainLoop *loop = (GMainLoop *) user_data; > + > + g_printerr("%s: caught hangup/quit signal, quitting", __func__); > + g_main_loop_quit(loop); > + return true; > +} > + > +static void panic(VuDev *dev, const char *msg) > +{ > + g_critical("%s\n", msg); > + exit(EXIT_FAILURE); > +} > + > +/* Print vhost-user.json backend program capabilities */ > +static void print_capabilities(void) > +{ > + printf("{\n"); > + printf(" \"type\": \"RNG\"\n"); > + printf(" \"filename\": [ RNG source ]\n"); > + printf("}\n"); > +} > + > +static GOptionEntry options[] = { > + { "socket-path", 's', 0, G_OPTION_ARG_FILENAME, &socket_path, > + "Location of vhost-user Unix domain socket, incompatible with --fd", > + "PATH" }, > + { "fd", 'f', 0, G_OPTION_ARG_INT, &socket_fd, > + "Specify the backend file-descriptor, incompatible with --socket-path", > + "FD" }, > + { "period", 'p', 0, G_OPTION_ARG_INT, &period_ms, > + "Time needed (in ms) to transfer a maximum amount of byte", NULL }, > + { "max-bytes", 'm', 0, G_OPTION_ARG_INT64, &max_bytes, > + "Maximum amount of byte that can be transferred in a period", NULL }, > + { "filename", 'n', 0, G_OPTION_ARG_FILENAME, &source_path, > + "RNG source, defaults to /dev/urandom", "PATH" }, > + { "print-capabilities", 'c', 0, G_OPTION_ARG_NONE, &print_cap, > + "Output to stdout the backend capabilities in JSON format and exit", > + NULL}, > + { "verbose", 'v', 0, G_OPTION_ARG_NONE, &verbose, > + "Be more verbose in output", NULL}, > + { NULL } > +}; > + > +int main(int argc, char *argv[]) > +{ > + GError *error = NULL; > + GOptionContext *context; > + g_autoptr(GSocket) socket = NULL; > + char default_source[] = "/dev/urandom"; > + char *source = default_source; > + VuRNG rng; > + > + context = g_option_context_new("vhost-user emulation of RNG device"); > + g_option_context_add_main_entries(context, options, "vhost-user-rng"); > + if (!g_option_context_parse(context, &argc, &argv, &error)) { > + g_printerr("option parsing failed: %s\n", error->message); > + exit(1); > + } > + > + if (print_cap) { > + print_capabilities(); > + exit(0); > + } > + > + if (!socket_path && socket_fd < 0) { > + g_printerr("Please specify either --fd or --socket-path\n"); > + exit(EXIT_FAILURE); > + } > + > + if (socket_path && socket_fd > 0) { > + g_printerr("Either --fd or --socket-path, not both\n"); > + exit(EXIT_FAILURE); > + } > + > + if (max_bytes > INT64_MAX) { > + g_printerr("'max-bytes' parameter must be non-negative, " > + "and less than 2^63\n"); > + exit(EXIT_FAILURE); > + } > + > + if (period_ms <= 0) { > + g_printerr("'period' parameter expects a positive integer\n"); > + exit(EXIT_FAILURE); > + } > + > + /* > + * Now create a vhost-user socket that we will receive messages > + * on. Once we have our handler set up we can enter the glib main > + * loop. > + */ > + if (socket_path) { > + g_autoptr(GSocketAddress) addr = g_unix_socket_address_new(socket_path); > + g_autoptr(GSocket) bind_socket = g_socket_new(G_SOCKET_FAMILY_UNIX, > + G_SOCKET_TYPE_STREAM, > + G_SOCKET_PROTOCOL_DEFAULT, > + &error); > + > + if (!g_socket_bind(bind_socket, addr, false, &error)) { > + g_printerr("Failed to bind to socket at %s (%s).\n", > + socket_path, error->message); > + exit(EXIT_FAILURE); > + } > + if (!g_socket_listen(bind_socket, &error)) { > + g_printerr("Failed to listen on socket %s (%s).\n", > + socket_path, error->message); > + } > + g_message("awaiting connection to %s", socket_path); > + socket = g_socket_accept(bind_socket, NULL, &error); > + if (!socket) { > + g_printerr("Failed to accept on socket %s (%s).\n", > + socket_path, error->message); > + } > + } else { > + socket = g_socket_new_from_fd(socket_fd, &error); > + if (!socket) { > + g_printerr("Failed to connect to FD %d (%s).\n", > + socket_fd, error->message); > + exit(EXIT_FAILURE); > + } > + } > + > + /* Overwrite default RNG source with what user provided, if any */ > + if (source_path) { > + source = source_path; > + } > + > + source_fd = open(source, O_RDWR); > + if (source_fd < 0) { > + g_printerr("Failed to open RNG source %s\n", source); > + g_socket_close(socket, &error); > + unlink(socket_path); > + exit(EXIT_FAILURE); > + } > + > + /* catch exit signals */ > + g_unix_signal_add(SIGHUP, hangup, rng.loop); > + g_unix_signal_add(SIGINT, hangup, rng.loop); > + > + /* > + * Create the main loop first so all the various sources can be > + * added. As well as catching signals we need to ensure vug_init > + * can add it's GSource watches. > + */ > + rng.loop = g_main_loop_new(NULL, FALSE); > + > + if (!vug_init(&rng.dev, 1, g_socket_get_fd(socket), > + panic, &vuiface)) { > + g_printerr("Failed to initialize libvhost-user-glib.\n"); > + exit(EXIT_FAILURE); > + } > + > + rng.quota_remaining = max_bytes; > + rng.activate_timer = true; > + pthread_mutex_init(&rng.rng_mutex, NULL); > + pthread_cond_init(&rng.rng_cond, NULL); > + setup_timer(&rng); > + > + if (verbose) { > + g_info("period_ms: %d tv_sec: %ld tv_nsec: %lu\n", > + period_ms, rng.ts.it_value.tv_sec, rng.ts.it_value.tv_nsec); > + } > + > + g_message("entering main loop, awaiting messages"); > + g_main_loop_run(rng.loop); > + g_message("finished main loop, cleaning up"); > + > + g_main_loop_unref(rng.loop); > + vug_deinit(&rng.dev); > + timer_delete(rng.rate_limit_timer); > + close(source_fd); > + unlink(socket_path); > +} > diff --git a/tools/vhost-user-rng/meson.build b/tools/vhost-user-rng/meson.build > new file mode 100644 > index 000000000000..4dc386daf335 > --- /dev/null > +++ b/tools/vhost-user-rng/meson.build > @@ -0,0 +1,10 @@ > +executable('vhost-user-rng', files( > + 'main.c'), > + dependencies: [qemuutil, glib, gio, rt], > + install: true, > + install_dir: get_option('libexecdir')) > + > +configure_file(input: '50-qemu-rng.json.in', > + output: '50-qemu-rng.json', > + configuration: config_host, > + install_dir: qemu_datadir / 'vhost-user') > -- > 2.25.1 > > -- > Stratos-dev mailing list > Stratos-dev(a)op-lists.linaro.org > https://op-lists.linaro.org/mailman/listinfo/stratos-dev

3 years, 6 months

Linaro Stratos Agenda for June 10th

by Mike Holmes

Hi All The Stratos call will be upon us again next week; we don't have a key agenda item yet [1] I added a back of the envelope summary of the work happening Linaro, which is relevant to Stratos primarily from an Automotive context [2]. This is subject to a large number of caveats. Does anyone have a topic to raise? Mike [1] https://linaro.atlassian.net/wiki/spaces/STR/pages/28503343751/2021-06-10+P… [2] https://linaro.atlassian.net/wiki/spaces/STR/pages/28503377401/Demonstrable… -- Mike Holmes (he / him / his) | Director, Foundation Technologies, Linaro Mike.Holmes(a)linaro.org <mike.holmes(a)linaro.org> "Work should be fun and collaborative; the rest follows."

3 years, 6 months

[PATCH 0/5] virtio: Add vhost-user based RNG service

by Mathieu Poirier

Hi all, This sets adds a vhost-user based random number generator (RNG), similar to what has been done for i2c and virtiofsd. In fact the implementation for vhost-user-rng and vhost-user-rng-pci follow what was done for vhost-user-i2c. Applies cleanly to git://git.qemu.org/qemu.git master (52848929b70d). Regards, Mathieu Mathieu Poirier (5): vhost-user-rng: Add vhost-user-rng implementation vhost-user-rng-pci: Add vhost-user-rng-pci implementation vhost-user-rng: backend: Add RNG vhost-user daemon implementation docs: Add documentation for vhost based RNG implementation MAINTAINERS: Add maintainer for vhost-user RNG implementation MAINTAINERS | 9 + docs/tools/vhost-user-rng.rst | 74 +++++ hw/virtio/Kconfig | 5 + hw/virtio/meson.build | 2 + hw/virtio/vhost-user-rng-pci.c | 79 +++++ hw/virtio/vhost-user-rng.c | 294 +++++++++++++++++ include/hw/virtio/vhost-user-rng.h | 33 ++ tools/meson.build | 8 + tools/vhost-user-rng/50-qemu-rng.json.in | 5 + tools/vhost-user-rng/main.c | 403 +++++++++++++++++++++++ tools/vhost-user-rng/meson.build | 10 + 11 files changed, 922 insertions(+) create mode 100644 docs/tools/vhost-user-rng.rst create mode 100644 hw/virtio/vhost-user-rng-pci.c create mode 100644 hw/virtio/vhost-user-rng.c create mode 100644 include/hw/virtio/vhost-user-rng.h create mode 100644 tools/vhost-user-rng/50-qemu-rng.json.in create mode 100644 tools/vhost-user-rng/main.c create mode 100644 tools/vhost-user-rng/meson.build -- 2.25.1

3 years, 6 months

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Stratos-dev June 2021