hexagonrpcd: add apps_mem interface implementation

The apps_mem interface enables the FastRPC shell to load skel ELFs,
such as libhexagon_nn_skel.so.

hexagonrpcd/apps_mem.c

@@ -0,0 +1,143 @@
+/*
+ * FastRPC memory mapping interface implementation
+ *
+ * Copyright (C) 2024 The Sensor Shell Contributors
+ *
+ * This file is part of sensh.
+ *
+ * Sensh 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 3 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#include <inttypes.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <misc/fastrpc.h>
+#include <sys/ioctl.h>
+
+#include "aee_error.h"
+#include "apps_mem.h"
+#include "interfaces/apps_mem.def"
+#include "listener.h"
+
+// See fastrpc.git/src/apps_mem_imp.c
+#define ADSP_MMAP_HEAP_ADDR 4
+#define ADSP_MMAP_REMOTE_HEAP_ADDR 8
+#define ADSP_MMAP_ADD_PAGES   0x1000
+
+struct apps_mem_ctx {
+	int fd;
+};
+
+static uint32_t apps_mem_request_map64(void *data,
+				       const struct fastrpc_io_buffer *inbufs,
+				       struct fastrpc_io_buffer *outbufs)
+{
+	struct apps_mem_ctx *ctx = data;
+	const struct {
+		uint32_t heap_id;
+		uint32_t lflags;
+		uint32_t rflags;
+		uint32_t padding;
+		uint64_t vin;
+		uint64_t len;
+	} *first_in = inbufs[0].p;
+	struct {
+		uint64_t vapps;
+		uint64_t vadsp;
+	} *first_out = outbufs[0].p;
+	struct fastrpc_req_mmap mmap;
+	int ret;
+
+	if (!(first_in->rflags & ADSP_MMAP_ADD_PAGES)) {
+		fprintf(stderr, "Unsupported mmap operation: DMA buffer request\n");
+		return AEE_EUNSUPPORTED;
+	}
+
+	mmap.fd = -1;
+	mmap.flags = first_in->rflags;
+	mmap.vaddrin = 0;
+	mmap.size = first_in->len;
+
+	ret = ioctl(ctx->fd, FASTRPC_IOCTL_MMAP, &mmap);
+	if (ret == -1) {
+		perror("Memory map failed");
+		return AEE_EFAILED;
+	} else if (ret) {
+		fprintf(stderr, "Memory map failed: %s\n", aee_strerror[ret]);
+		return ret;
+	}
+
+#if HEXAGONRPC_VERBOSE
+	printf("mmap(%d, %x, %x, %lu, %lu) -> %" PRIx64 "\n",
+	       first_in->heap_id,
+	       first_in->lflags,
+	       first_in->rflags,
+	       first_in->vin,
+	       first_in->len,
+	       mmap.vaddrout);
+#endif
+
+	first_out->vapps = 0;
+	first_out->vadsp = mmap.vaddrout & 0xFFFFFFFF;
+	return 0;
+}
+
+struct fastrpc_interface *fastrpc_apps_mem_init(int fd)
+{
+	struct fastrpc_interface *iface;
+	struct apps_mem_ctx *ctx;
+
+	iface = malloc(sizeof(*iface));
+	if (iface == NULL)
+		return NULL;
+
+	ctx = calloc(1, sizeof(*ctx));
+	if (ctx == NULL)
+		goto err_free_iface;
+
+	memcpy(iface, &apps_mem_interface, sizeof(*iface));
+
+	ctx->fd = fd;
+
+	iface->data = ctx;
+
+	return iface;
+
+err_free_iface:
+	free(iface);
+
+	return NULL;
+}
+
+void fastrpc_apps_mem_deinit(struct fastrpc_interface *iface)
+{
+	free(iface->data);
+	free(iface);
+}
+
+static const struct fastrpc_function_impl apps_mem_procs[] = {
+	{ .def = NULL, .impl = NULL, },
+	{ .def = NULL, .impl = NULL, },
+	{ .def = &apps_mem_request_map64_def, .impl = apps_mem_request_map64, },
+	{ .def = NULL, .impl = NULL, },
+	{ .def = NULL, .impl = NULL, },
+	{ .def = NULL, .impl = NULL, },
+};
+
+const struct fastrpc_interface apps_mem_interface = {
+	.name = "apps_mem",
+	.n_procs = 6,
+	.procs = apps_mem_procs,
+};

hexagonrpcd/apps_mem.h

@@ -0,0 +1,30 @@
+/*
+ * FastRPC operating system interface - context initialization
+ *
+ * Copyright (C) 2024 The Sensor Shell Contributors
+ *
+ * This file is part of HexagonRPC.
+ *
+ * HexagonRPC 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 3 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#ifndef APPS_MEM_H
+#define APPS_MEM_H
+
+#include "listener.h"
+
+struct fastrpc_interface *fastrpc_apps_mem_init();
+void fastrpc_apps_mem_deinit(struct fastrpc_interface *iface);
+
+#endif

hexagonrpcd/listener.h

@@ -44,6 +44,7 @@ struct fastrpc_interface {
 
 extern const struct fastrpc_interface localctl_interface;
 
+extern const struct fastrpc_interface apps_mem_interface;
 extern const struct fastrpc_interface apps_std_interface;
 
 int run_fastrpc_listener(int fd,

hexagonrpcd/meson.build

@@ -1,5 +1,6 @@
 executable('hexagonrpcd',
   'aee_error.c',
+  'apps_mem.c',
   'apps_std.c',
   'interfaces.c',
   'hexagonfs.c',

hexagonrpcd/rpcd.c

@@ -35,6 +35,7 @@
 #include <sys/types.h>
 
 #include "aee_error.h"
+#include "apps_mem.h"
 #include "apps_std.h"
 #include "hexagonfs.h"
 #include "interfaces/adsp_default_listener.def"
@@ -253,7 +254,7 @@ static void *start_reverse_tunnel(int fd, const char *device_dir, const char *ds
 {
 	struct fastrpc_interface **ifaces;
 	struct hexagonfs_dirent *root_dir;
-	size_t n_ifaces = 2;
+	size_t n_ifaces = 3;
 	int ret;
 
 	ifaces = malloc(sizeof(struct fastrpc_interface) * n_ifaces);
@@ -271,6 +272,7 @@ static void *start_reverse_tunnel(int fd, const char *device_dir, const char *ds
 
 	// Dynamic interfaces with no hardcoded handle
 	ifaces[1] = fastrpc_apps_std_init(root_dir);
+	ifaces[2] = fastrpc_apps_mem_init(fd);
 
 	ret = register_fastrpc_listener(fd);
 	if (ret)