From 5cce7626f33e92f624ac06b613125813fb47d445 Mon Sep 17 00:00:00 2001
From: Chen Qi <Qi.Chen@windriver.com>
Date: Wed, 28 Feb 2018 21:05:39 -0800
Subject: [PATCH 08/31] Revert "udev: remove userspace firmware loading
 support"

This reverts commit be2ea723b1d023b3d385d3b791ee4607cbfb20ca.
Userspace firmware loading support is needed for Linux < 3.7.

Upstream-Status: Inappropriate [OE specific]

Signed-off-by: Jonathan Liu <net147@gmail.com>
Signed-off-by: Khem Raj <raj.khem@gmail.com>
Signed-off-by: Chen Qi <Qi.Chen@windriver.com>
---
 README                           |   4 +-
 TODO                             |   1 +
 meson.build                      |   9 +++
 meson_options.txt                |   2 +
 rules/meson.build                |   4 +
 src/udev/meson.build             |   4 +
 src/udev/udev-builtin-firmware.c | 154 +++++++++++++++++++++++++++++++++++++++
 src/udev/udev-builtin.c          |   3 +
 src/udev/udev.h                  |   6 ++
 src/udev/udevd.c                 |  12 +++
 10 files changed, 197 insertions(+), 2 deletions(-)
 create mode 100644 src/udev/udev-builtin-firmware.c

diff --git a/README b/README
index 8807e5cfe..bfd7a35de 100644
--- a/README
+++ b/README
@@ -58,8 +58,8 @@ REQUIREMENTS:
         Legacy hotplug slows down the system and confuses udev:
           CONFIG_UEVENT_HELPER_PATH=""
 
-        Userspace firmware loading is not supported and should
-        be disabled in the kernel:
+        Userspace firmware loading is deprecated, will go away, and
+        sometimes causes problems:
           CONFIG_FW_LOADER_USER_HELPER=n
 
         Some udev rules and virtualization detection relies on it:
diff --git a/TODO b/TODO
index a77028c7b..39e72d7ec 100644
--- a/TODO
+++ b/TODO
@@ -783,6 +783,7 @@ Features:
 * initialize the hostname from the fs label of /, if /etc/hostname does not exist?
 
 * udev:
+  - remove src/udev/udev-builtin-firmware.c (CONFIG_FW_LOADER_USER_HELPER=n)
   - move to LGPL
   - kill scsi_id
   - add trigger --subsystem-match=usb/usb_device device
diff --git a/meson.build b/meson.build
index 918101d6b..9c25022a4 100644
--- a/meson.build
+++ b/meson.build
@@ -72,6 +72,12 @@ conf.set10('HAVE_SYSV_COMPAT', have,
            description : 'SysV init scripts and rcN.d links are supported')
 m4_defines += have ? ['-DHAVE_SYSV_COMPAT'] : []
 
+firmware_path = get_option('firmware-path')
+have = firmware_path != ''
+conf.set10('HAVE_FIRMWARE', have,
+           description : 'Userspace firmware loading is supported')
+m4_defines += have ? ['-DHAVE_FIRMWARE'] : []
+
 # join_paths ignore the preceding arguments if an absolute component is
 # encountered, so this should canonicalize various paths when they are
 # absolute or relative.
@@ -178,6 +184,7 @@ conf.set_quoted('SYSTEM_CONFIG_UNIT_PATH',                    join_paths(pkgsysc
 conf.set_quoted('SYSTEM_DATA_UNIT_PATH',                      systemunitdir)
 conf.set_quoted('SYSTEM_SYSVINIT_PATH',                       sysvinit_path)
 conf.set_quoted('SYSTEM_SYSVRCND_PATH',                       sysvrcnd_path)
+conf.set_quoted('FIRMWARE_PATH',                              firmware_path)
 conf.set_quoted('RC_LOCAL_SCRIPT_PATH_START',                 get_option('rc-local'))
 conf.set_quoted('RC_LOCAL_SCRIPT_PATH_STOP',                  get_option('halt-local'))
 conf.set_quoted('USER_CONFIG_UNIT_PATH',                      join_paths(pkgsysconfdir, 'user'))
@@ -258,6 +265,7 @@ substs.set('SYSTEMCTL',                                       join_paths(rootbin
 substs.set('RANDOM_SEED',                                     join_paths(randomseeddir, 'random-seed'))
 substs.set('SYSTEM_SYSVINIT_PATH',                            sysvinit_path)
 substs.set('SYSTEM_SYSVRCND_PATH',                            sysvrcnd_path)
+substs.set('FIRMWARE_PATH',                                   firmware_path)
 substs.set('RC_LOCAL_SCRIPT_PATH_START',                      get_option('rc-local'))
 substs.set('RC_LOCAL_SCRIPT_PATH_STOP',                       get_option('halt-local'))
 
@@ -2715,6 +2723,7 @@ status = [
         'roothome directory:                @0@'.format(roothomedir),
         'SysV init scripts:                 @0@'.format(sysvinit_path),
         'SysV rc?.d directories:            @0@'.format(sysvrcnd_path),
+        'firmware path:                     @0@'.format(firmware_path),
         'PAM modules directory:             @0@'.format(pamlibdir),
         'PAM configuration directory:       @0@'.format(pamconfdir),
         'RPM macros directory:              @0@'.format(rpmmacrosdir),
diff --git a/meson_options.txt b/meson_options.txt
index 0b24f0e0f..92d25fa35 100644
--- a/meson_options.txt
+++ b/meson_options.txt
@@ -108,6 +108,8 @@ option('tmpfiles', type : 'boolean',
        description : 'support for tmpfiles.d')
 option('importd', type : 'combo', choices : ['auto', 'true', 'false'],
        description : 'install the systemd-importd daemon')
+option('firmware-path', type : 'string', value : '',
+       description : 'Firmware search path')
 option('hwdb', type : 'boolean',
        description : 'support for the hardware database')
 option('rfkill', type : 'boolean',
diff --git a/rules/meson.build b/rules/meson.build
index e253b9f59..5eee5fbca 100644
--- a/rules/meson.build
+++ b/rules/meson.build
@@ -41,6 +41,10 @@ rules = files('''
 install_data(rules,
              install_dir : udevrulesdir)
 
+if conf.get('HAVE_FIRMWARE') == 1
+        install_data('50-firmware.rules', install_dir : udevrulesdir)
+endif
+
 all_rules = rules
 
 rules_in = '''
diff --git a/src/udev/meson.build b/src/udev/meson.build
index de2fd2d9c..b6b0ca006 100644
--- a/src/udev/meson.build
+++ b/src/udev/meson.build
@@ -67,6 +67,10 @@ if conf.get('HAVE_ACL') == 1
                                  sd_login_c]
 endif
 
+if conf.get('HAVE_FIRMWARE') == 1
+        libudev_core_sources += ['udev-builtin-firmware.c']
+endif
+
 ############################################################
 
 generate_keyboard_keys_list = find_program('generate-keyboard-keys-list.sh')
diff --git a/src/udev/udev-builtin-firmware.c b/src/udev/udev-builtin-firmware.c
new file mode 100644
index 000000000..bd8c2fb96
--- /dev/null
+++ b/src/udev/udev-builtin-firmware.c
@@ -0,0 +1,154 @@
+/*
+ * firmware - Kernel firmware loader
+ *
+ * Copyright (C) 2009 Piter Punk <piterpunk@slackware.com>
+ * Copyright (C) 2009-2011 Kay Sievers <kay@vrfy.org>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details:*
+ */
+
+#include <unistd.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+#include <getopt.h>
+#include <errno.h>
+#include <stdbool.h>
+#include <sys/utsname.h>
+#include <sys/stat.h>
+
+#include "udev.h"
+
+static bool set_loading(struct udev *udev, char *loadpath, const char *state) {
+        FILE *ldfile;
+
+        ldfile = fopen(loadpath, "we");
+        if (ldfile == NULL) {
+                log_error("error: can not open '%s'", loadpath);
+                return false;
+        };
+        fprintf(ldfile, "%s\n", state);
+        fclose(ldfile);
+        return true;
+}
+
+static bool copy_firmware(struct udev *udev, const char *source, const char *target, size_t size) {
+        char *buf;
+        FILE *fsource = NULL, *ftarget = NULL;
+        bool ret = false;
+
+        buf = malloc(size);
+        if (buf == NULL) {
+                log_error("No memory available to load firmware file");
+                return false;
+        }
+
+        log_debug("writing '%s' (%zi) to '%s'", source, size, target);
+
+        fsource = fopen(source, "re");
+        if (fsource == NULL)
+                goto exit;
+        ftarget = fopen(target, "we");
+        if (ftarget == NULL)
+                goto exit;
+        if (fread(buf, size, 1, fsource) != 1)
+                goto exit;
+        if (fwrite(buf, size, 1, ftarget) == 1)
+                ret = true;
+exit:
+        if (ftarget != NULL)
+                fclose(ftarget);
+        if (fsource != NULL)
+                fclose(fsource);
+        free(buf);
+        return ret;
+}
+
+static int builtin_firmware(struct udev_device *dev, int argc, char *argv[], bool test) {
+        struct udev *udev = udev_device_get_udev(dev);
+        static const char *searchpath[] = { FIRMWARE_PATH };
+        char loadpath[UTIL_PATH_SIZE];
+        char datapath[UTIL_PATH_SIZE];
+        char fwpath[UTIL_PATH_SIZE];
+        const char *firmware;
+        FILE *fwfile = NULL;
+        struct utsname kernel;
+        struct stat statbuf;
+        unsigned int i;
+        int rc = EXIT_SUCCESS;
+
+        firmware = udev_device_get_property_value(dev, "FIRMWARE");
+        if (firmware == NULL) {
+                log_error("firmware parameter missing");
+                rc = EXIT_FAILURE;
+                goto exit;
+        }
+
+        /* lookup firmware file */
+        uname(&kernel);
+        for (i = 0; i < ELEMENTSOF(searchpath); i++) {
+                strscpyl(fwpath, sizeof(fwpath), searchpath[i], kernel.release, "/", firmware, NULL);
+                fwfile = fopen(fwpath, "re");
+                if (fwfile != NULL)
+                        break;
+
+                strscpyl(fwpath, sizeof(fwpath), searchpath[i], firmware, NULL);
+                fwfile = fopen(fwpath, "re");
+                if (fwfile != NULL)
+                        break;
+        }
+
+        strscpyl(loadpath, sizeof(loadpath), udev_device_get_syspath(dev), "/loading", NULL);
+
+        if (fwfile == NULL) {
+                log_debug("did not find firmware file '%s'", firmware);
+                rc = EXIT_FAILURE;
+                /*
+                 * Do not cancel the request in the initrd, the real root might have
+                 * the firmware file and the 'coldplug' run in the real root will find
+                 * this pending request and fulfill or cancel it.
+                 * */
+                if (!in_initrd())
+                        set_loading(udev, loadpath, "-1");
+                goto exit;
+        }
+
+        if (stat(fwpath, &statbuf) < 0 || statbuf.st_size == 0) {
+                if (!in_initrd())
+                        set_loading(udev, loadpath, "-1");
+                rc = EXIT_FAILURE;
+                goto exit;
+        }
+
+        if (!set_loading(udev, loadpath, "1"))
+                goto exit;
+
+        strscpyl(datapath, sizeof(datapath), udev_device_get_syspath(dev), "/data", NULL);
+        if (!copy_firmware(udev, fwpath, datapath, statbuf.st_size)) {
+                log_error("error sending firmware '%s' to device", firmware);
+                set_loading(udev, loadpath, "-1");
+                rc = EXIT_FAILURE;
+                goto exit;
+        };
+
+        set_loading(udev, loadpath, "0");
+exit:
+        if (fwfile)
+                fclose(fwfile);
+        return rc;
+}
+
+const struct udev_builtin udev_builtin_firmware = {
+        .name = "firmware",
+        .cmd = builtin_firmware,
+        .help = "kernel firmware loader",
+        .run_once = true,
+};
diff --git a/src/udev/udev-builtin.c b/src/udev/udev-builtin.c
index db2b6874f..ccd88638c 100644
--- a/src/udev/udev-builtin.c
+++ b/src/udev/udev-builtin.c
@@ -32,6 +32,9 @@ static const struct udev_builtin *builtins[] = {
         [UDEV_BUILTIN_BLKID] = &udev_builtin_blkid,
 #endif
         [UDEV_BUILTIN_BTRFS] = &udev_builtin_btrfs,
+#if HAVE_FIRMWARE
+        [UDEV_BUILTIN_FIRMWARE] = &udev_builtin_firmware,
+#endif
         [UDEV_BUILTIN_HWDB] = &udev_builtin_hwdb,
         [UDEV_BUILTIN_INPUT_ID] = &udev_builtin_input_id,
         [UDEV_BUILTIN_KEYBOARD] = &udev_builtin_keyboard,
diff --git a/src/udev/udev.h b/src/udev/udev.h
index ea11c2d29..c47dd3d88 100644
--- a/src/udev/udev.h
+++ b/src/udev/udev.h
@@ -151,6 +151,9 @@ enum udev_builtin_cmd {
         UDEV_BUILTIN_BLKID,
 #endif
         UDEV_BUILTIN_BTRFS,
+#if HAVE_FIRMWARE
+        UDEV_BUILTIN_FIRMWARE,
+#endif
         UDEV_BUILTIN_HWDB,
         UDEV_BUILTIN_INPUT_ID,
         UDEV_BUILTIN_KEYBOARD,
@@ -179,6 +182,9 @@ struct udev_builtin {
 extern const struct udev_builtin udev_builtin_blkid;
 #endif
 extern const struct udev_builtin udev_builtin_btrfs;
+#if HAVE_FIRMWARE
+extern const struct udev_builtin udev_builtin_firmware;
+#endif
 extern const struct udev_builtin udev_builtin_hwdb;
 extern const struct udev_builtin udev_builtin_input_id;
 extern const struct udev_builtin udev_builtin_keyboard;
diff --git a/src/udev/udevd.c b/src/udev/udevd.c
index 5c757d513..2f3313007 100644
--- a/src/udev/udevd.c
+++ b/src/udev/udevd.c
@@ -127,6 +127,9 @@ struct event {
         bool is_block;
         sd_event_source *timeout_warning;
         sd_event_source *timeout;
+#if HAVE_FIRMWARE
+        bool nodelay;
+#endif
 };
 
 static void event_queue_cleanup(Manager *manager, enum event_state type);
@@ -609,6 +612,10 @@ static int event_queue_insert(Manager *manager, struct udev_device *dev) {
         event->devnum = udev_device_get_devnum(dev);
         event->is_block = streq("block", udev_device_get_subsystem(dev));
         event->ifindex = udev_device_get_ifindex(dev);
+#if HAVE_FIRMWARE
+        if (streq(udev_device_get_subsystem(dev), "firmware"))
+                event->nodelay = true;
+#endif
 
         log_debug("seq %llu queued, '%s' '%s'", udev_device_get_seqnum(dev),
              udev_device_get_action(dev), udev_device_get_subsystem(dev));
@@ -692,6 +699,11 @@ static bool is_devpath_busy(Manager *manager, struct event *event) {
                         return true;
                 }
 
+#if HAVE_FIRMWARE
+                /* allow to bypass the dependency tracking */
+                if (event->nodelay)
+                        continue;
+#endif
                 /* parent device event found */
                 if (event->devpath[common] == '/') {
                         event->delaying_seqnum = loop_event->seqnum;
-- 
2.13.0