feat(ipc): add ipc linux driver

Signed-off-by: João Peixoto <[email protected]>

.github/workflows/clang-format-check.yml

@@ -27,5 +27,5 @@ jobs:
       # Step 3: Run clang-format check
       - name: Run clang-format check
         run: |
-          FILES_TO_CHECK=$(find ./io_dispatcher -name "*.c" -o -name "*.h")
+          FILES_TO_CHECK=$(find ./io_dispatcher ./ipc -name "*.c" -o -name "*.h")
           clang-format-20 -i $FILES_TO_CHECK --dry-run --Werror

CONTRIBUTORS

@@ -1,4 +1,6 @@
-# This is a list of people who contributed code to the bao hypervisor I/O dispatcher
-# Linux kernel module by chronological order of first contribution.
+# This is a list of people who contributed code to the Bao Hypervisor
+# Linux drivers by chronological order of first contribution.
 
+David Cerdeira <[email protected]>
+José Martins <[email protected]>
 João Peixoto <[email protected]>

Makefile

@@ -1,10 +1,17 @@
 # Declare targets as phony to ensure they always run
-.PHONY: io_dispatcher clean help
+.PHONY: io_dispatcher ipc clean help
 
 # Target for building only the io_dispatcher module
 io_dispatcher:
 	$(MAKE) -C $(KERN_DIR) M=$(PWD)/io_dispatcher CROSS_COMPILE=$(CROSS_COMPILE) ARCH=$(ARCH) modules
 
+# Target for building only the ipc module
+ipc:
+	$(MAKE) -C $(KERN_DIR) M=$(PWD)/ipc CROSS_COMPILE=$(CROSS_COMPILE) ARCH=$(ARCH) modules
+
+# Target for building all modules
+all: io_dispatcher ipc
+
 # Target for cleaning 
 clean:
 	$(MAKE) -C $(KERN_DIR) M=$(PWD) CROSS_COMPILE=$(CROSS_COMPILE) ARCH=$(ARCH) clean

README.md

@@ -3,4 +3,5 @@
 This repository hosts all Linux drivers and kernel modules developed for the Bao Hypervisor.
 
 Currently included:
-- [I/O Dispatcher](io_dispatcher/README.md) system
+- [I/O Dispatcher](io_dispatcher/README.md) system
+- [IPC](ipc/README.md) module

ipc/Makefile

@@ -0,0 +1,3 @@
+# Object files and module definition
+obj-m += bao_ipc.o
+bao_ipc-y := ipcshmem.o

ipc/README.md

@@ -0,0 +1,28 @@
+# Bao Hypervisor IPC Through Shared-memory Kernel Module
+
+The IPC kernel module enables communication between two VMs via a mutually established shared memory region.
+
+### Setup instructions
+
+1. Setup global environment variables:
+```
+export ARCH=arm64|arm32|riscv
+export CROSS_COMPILE=path/to/your/toolchain
+export KERN_DIR=path/to/your/linux
+```
+
+2. Build the out of tree kernel module:
+```
+make ipc
+```
+
+3. Copy the `bao_ipc.ko` file to your target filesystem.
+
+### Run instructions
+
+1. When the Backend VM boots up, insert the kernel module:
+```
+insmod bao_ipc.ko
+```
+
+2. From now on, you should be able to see the `/dev/baoipcX` device node if configured any Bao IPC object.