db845c: qcom: Add userspace tools to talk to dsp and modem

Add Qcom userspace tools and their respective sepolicy rules.

Userspace tools are downloaded from following github:

To trigger loading of wlan firmware on SDM845
git clone https://github.com/andersson/pd-mapper

Userspace reference for net/qrtr in the Linux kernel
git clone https://github.com/andersson/qrtr

Qualcomm Remote Filesystem Service Implementation
git clone https://github.com/andersson/rmtfs

Trivial File Transfer Protocol server over AF_QIPCRTR
git clone https://github.com/andersson/tqftpserv

Change-Id: Ic466af6fef010a9b71c90e38205f49a876b001e2
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
diff --git a/qcom/tqftpserv/translate.c b/qcom/tqftpserv/translate.c
new file mode 100644
index 0000000..e95dee5
--- /dev/null
+++ b/qcom/tqftpserv/translate.c
@@ -0,0 +1,183 @@
+/*
+ * Copyright (c) 2019, Linaro Ltd.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ *
+ * 3. Neither the name of the copyright holder nor the names of its contributors
+ * may be used to endorse or promote products derived from this software without
+ * specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <dirent.h>
+#include <err.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <libgen.h>
+#include <limits.h>
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "translate.h"
+
+#define READONLY_PATH	"/readonly/firmware/image/"
+#define READWRITE_PATH	"/readwrite/"
+
+#define FIRMWARE_BASE	"/lib/firmware/"
+
+/**
+ * translate_readonly() - open "file" residing with remoteproc firmware
+ * @file:	file requested, stripped of "/readonly/image/" prefix
+ *
+ * It is assumed that the readonly files requested by the client resides under
+ * /lib/firmware in the same place as its associated remoteproc firmware.  This
+ * function scans through all entries under /sys/class/remoteproc and read the
+ * dirname of each "firmware" file in an attempt to find, and open(2), the
+ * requested file.
+ *
+ * As these files are readonly, it's not possible to pass flags to open(2).
+ *
+ * Return: opened fd on success, -1 otherwise
+ */
+static int translate_readonly(const char *file)
+{
+	char firmware_value[PATH_MAX];
+	char firmware_attr[32];
+	char path[PATH_MAX];
+	struct dirent *de;
+	int firmware_fd;
+	DIR *class_dir;
+	int class_fd;
+	ssize_t n;
+	int fd = -1;
+
+	class_fd = open("/sys/class/remoteproc", O_RDONLY | O_DIRECTORY);
+	if (class_fd < 0) {
+		warn("failed to open remoteproc class");
+		return -1;
+	}
+
+	class_dir = fdopendir(class_fd);
+	if (!class_dir) {
+		warn("failed to opendir");
+		goto close_class;
+	}
+
+	while ((de = readdir(class_dir)) != NULL) {
+		if (!strcmp(de->d_name, ".") || !strcmp(de->d_name, ".."))
+			continue;
+
+		if (strlen(de->d_name) + sizeof("/firmware") > sizeof(firmware_attr))
+			continue;
+		strcpy(firmware_attr, de->d_name);
+		strcat(firmware_attr, "/firmware");
+
+		firmware_fd = openat(class_fd, firmware_attr, O_RDONLY);
+		if (firmware_fd < 0)
+			continue;
+
+		n = read(firmware_fd, firmware_value, sizeof(firmware_value));
+		close(firmware_fd);
+		if (n < 0) {
+			continue;
+		}
+
+		if (strlen(FIRMWARE_BASE) + strlen(firmware_value) + 1 +
+		    strlen(file) + 1 > sizeof(path))
+			continue;
+
+		strcpy(path, FIRMWARE_BASE);
+		strcat(path, dirname(firmware_value));
+		strcat(path, "/");
+		strcat(path, file);
+
+		fd = open(path, O_RDONLY);
+		if (fd >= 0)
+			break;
+
+		if (errno != ENOENT)
+			warn("failed to open %s", path);
+	}
+
+	closedir(class_dir);
+
+close_class:
+	close(class_fd);
+
+	return fd;
+}
+
+/**
+ * translate_readwrite() - open "file" from a temporary directory
+ * @file:	relative path of the requested file, with /readwrite/ stripped
+ * @flags:	flags to be passed to open(2)
+ *
+ * Return: opened fd on success, -1 otherwise
+ */
+static int translate_readwrite(const char *file, int flags)
+{
+	int base;
+	int ret;
+	int fd;
+
+	ret = mkdir("/tmp/tqftpserv", 0700);
+	if (ret < 0 && errno != EEXIST) {
+		warn("failed to create /tmp/tqftpserv");
+		return -1;
+	}
+
+	base = open("/tmp/tqftpserv", O_RDONLY | O_DIRECTORY);
+	if (base < 0) {
+		warn("failed top open /tmp/tqftpserv");
+		return -1;
+	}
+
+	fd = openat(base, file, flags, 0600);
+	close(base);
+	if (fd < 0)
+		warn("failed to open %s", file);
+
+	return fd;
+}
+
+/**
+ * translate_open() - open file after translating path
+ *
+
+ * Strips /readonly/firmware/image and search among remoteproc firmware.
+ * Replaces /readwrite with a temporary directory.
+
+ */
+int translate_open(const char *path, int flags)
+{
+	if (!strncmp(path, READONLY_PATH, strlen(READONLY_PATH)))
+		return translate_readonly(path + strlen(READONLY_PATH));
+	else if (!strncmp(path, READWRITE_PATH, strlen(READWRITE_PATH)))
+		return translate_readwrite(path + strlen(READWRITE_PATH), flags);
+
+	fprintf(stderr, "invalid path %s, rejecting\n", path);
+	errno = ENOENT;
+	return -1;
+}