subsys: fs: Implementation of ext2 file system

doc/releases/release-notes-3.5.rst

@@ -283,6 +283,10 @@ Libraries / Subsystems
     :c:struct:`mgmt_group` when registering a transport. See
     :c:type:`smp_translate_error_fn` for function details.
 
+* File systems
+
+  * Added support for ext2 file system.
+
 HALs
 ****
 
@@ -313,5 +317,8 @@ Documentation
 Tests and Samples
 *****************
 
+* Created common sample for file systems (`fs_sample`). It originates from sample for FAT
+  (`fat_fs`) and supports both FAT and ext2 file systems.
+
 Known Issues
 ************

include/zephyr/fs/ext2.h

@@ -0,0 +1,45 @@
+/*
+ * Copyright (c) 2023 Antmicro <www.antmicro.com>
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#ifndef ZEPHYR_INCLUDE_FS_EXT2_H_
+#define ZEPHYR_INCLUDE_FS_EXT2_H_
+
+#include <stdint.h>
+
+/** @brief Configuration used to format ext2 file system.
+ *
+ * If a field is set to 0 then default value is used.
+ * (In volume name the first cell of an array must be 0 to use default value.)
+ *
+ * @param block_size Requested size of block.
+ * @param fs_size Requested size of file system. If 0 then whole available memory is used.
+ * @param bytes_per_inode Requested memory for one inode. It is used to calculate number of inodes
+ *	in created file system.
+ * @param uuid UUID for created file system. Used when set_uuid is true.
+ * @param volume_name Name for created file system.
+ * @param set_uuid If true then UUID from that structure is used in created file system.
+ *	If false then UUID (ver4) is generated.
+ */
+struct ext2_cfg {
+	uint32_t block_size;
+	uint32_t fs_size; /* Number of blocks that we want to take. */
+	uint32_t bytes_per_inode;
+	uint8_t uuid[16];
+	uint8_t volume_name[17]; /* If first byte is 0 then name ext2" is given. */
+	bool set_uuid;
+};
+
+#define FS_EXT2_DECLARE_DEFAULT_CONFIG(name)			\
+	static struct ext2_cfg name = {				\
+		.block_size = 1024,				\
+		.fs_size = 0x800000,				\
+		.bytes_per_inode = 4096,			\
+		.volume_name = {'e', 'x', 't', '2', '\0'},	\
+		.set_uuid = false,				\
+	}
+
+
+#endif /* ZEPHYR_INCLUDE_FS_EXT2_H_ */

include/zephyr/fs/fs.h

@@ -56,6 +56,9 @@ enum {
 	/** Identifier for in-tree LittleFS file system. */
 	FS_LITTLEFS,
 
+	/** Identifier for in-tree Ext2 file system. */
+	FS_EXT2,
+
 	/** Base identifier for external file systems. */
 	FS_TYPE_EXTERNAL_BASE,
 };

include/zephyr/fs/fs_interface.h

@@ -15,20 +15,33 @@ extern "C" {
 
 #if (CONFIG_FILE_SYSTEM_MAX_FILE_NAME - 0) > 0
 #define MAX_FILE_NAME CONFIG_FILE_SYSTEM_MAX_FILE_NAME
+
 #else /* CONFIG_FILE_SYSTEM_MAX_FILE_NAME */
 /* Select from enabled file systems */
-#if defined(CONFIG_FILE_SYSTEM_LITTLEFS)
-#define MAX_FILE_NAME 256
-#elif defined(CONFIG_FAT_FILESYSTEM_ELM)
+
+#if defined(CONFIG_FAT_FILESYSTEM_ELM)
+
 #if defined(CONFIG_FS_FATFS_LFN)
 #define MAX_FILE_NAME CONFIG_FS_FATFS_MAX_LFN
 #else /* CONFIG_FS_FATFS_LFN */
 #define MAX_FILE_NAME 12 /* Uses 8.3 SFN */
 #endif /* CONFIG_FS_FATFS_LFN */
-#else /* filesystem selection */
+
+#endif
+
+#if !defined(MAX_FILE_NAME) && defined(CONFIG_FILE_SYSTEM_EXT2)
+#define MAX_FILE_NAME 255
+#endif
+
+#if !defined(MAX_FILE_NAME) && defined(CONFIG_FILE_SYSTEM_LITTLEFS)
+#define MAX_FILE_NAME 256
+#endif
+
+#if !defined(MAX_FILE_NAME) /* filesystem selection */
 /* Use standard 8.3 when no filesystem is explicitly selected */
 #define MAX_FILE_NAME 12
 #endif /* filesystem selection */
+
 #endif /* CONFIG_FILE_SYSTEM_MAX_FILE_NAME */
 
 

samples/subsys/fs/fat_fs/Kconfig → samples/subsys/fs/fs_sample/Kconfig

@@ -1,20 +1,21 @@
 #
 # Copyright (c) 2023 Nordic Semiconductor ASA
+# Copyright (c) 2023 Antmicro <www.antmicro.com>
 #
 # SPDX-License-Identifier: Apache-2.0
 #
 
-mainmenu "FAT Filesystem Sample Application"
+mainmenu "Filesystems Sample Application"
 
-config SAMPLE_FATFS_CREATE_SOME_ENTRIES
+config FS_SAMPLE_CREATE_SOME_ENTRIES
 	bool "When no files are found on mounted partition create some"
 	default y
 	help
 	  In case when no files could be listed, because there are none,
 	  "some.dir" directory and "other.txt" file will be created
 	  and list will run again to show them. This is useful when
-	  showing how FAT works on non-SD devices like internal flash
-	  or (Q)SPI connected memories, where it is not possible to
+	  showing how file system works on non-SD devices like internal
+	  flash or (Q)SPI connected memories, where it is not possible to
 	  easily add files with use of other device.
 
 source "Kconfig.zephyr"

samples/subsys/fs/fat_fs/README.rst → samples/subsys/fs/fs_sample/README.rst

@@ -1,26 +1,24 @@
-.. _fat_fs:
+.. _fs_sample:
 
-FAT Filesystem Sample Application
+Filesystems Sample Application
 ###################################
 
 Overview
 ********
 
-This sample app demonstrates use of the filesystem API and uses the FAT file
+This sample app demonstrates use of the file system API and uses the FAT or Ext2 file
 system driver with SDHC card, SoC flash or external flash chip.
 
 To access device the sample uses :ref:`disk_access_api`.
 
 Requirements for SD card support
 ********************************
 
-This project requires SD card support and microSD card formatted with FAT filesystem.
-See the :ref:`disk_access_api` documentation for Zephyr implementation details.
-Boards that by default use SD card for storage:
-``arduino_mkrzero``, ``esp_wrover_kit``, ``mimxrt1050_evk``, ``nrf52840_blip``
-and  ``olimexino_stm32``.
-The sample should be able to run with any other board that has "zephyr,sdmmc-disk"
-DT node enabled.
+This project requires SD card support and microSD card formatted with proper file system
+(FAT or Ext2) See the :ref:`disk_access_api` documentation for Zephyr implementation details.
+Boards that by default use SD card for storage: ``arduino_mkrzero``, ``esp_wrover_kit``,
+``mimxrt1050_evk``, ``nrf52840_blip`` and  ``olimexino_stm32``. The sample should be able
+to run with any other board that has "zephyr,sdmmc-disk" DT node enabled.
 
 Requirements for setting up FAT FS on SoC flash
 ***********************************************
@@ -38,14 +36,14 @@ This type of configuration requires external flash device to be available
 on DK board. Currently following boards support the configuration:
 ``nrf52840dk_nrf52840`` by ``nrf52840dk_nrf52840_qspi`` configuration.
 
-Building and Running
-********************
+Building and Running FAT samples
+********************************
 
 Boards with default configurations, for example ``arduino_mkrzero`` or
 ``nrf52840dk_nrf52840`` using internal flash can be build using command:
 
 .. zephyr-app-commands::
-   :zephyr-app: samples/subsys/fs/fat_fs
+   :zephyr-app: samples/subsys/fs/fs_sample
    :board: nrf52840_blip
    :goals: build
    :compact:
@@ -57,7 +55,7 @@ for example ``nrf52840dk_nrf52840`` with MX25 device over QSPI, configuration
 and DTS overlays need to be also selected. The command would look like this:
 
 .. zephyr-app-commands::
-   :zephyr-app: samples/subsys/fs/fat_fs
+   :zephyr-app: samples/subsys/fs/fs_sample
    :board: nrf52840dk_nrf52840
    :gen-args: -DEXTRA_CONF_FILE=nrf52840dk_nrf52840_qspi.conf -DDTC_OVERLAY_FILE=nrf52840dk_nrf52840_qspi.overlay
    :goals: build
@@ -70,3 +68,20 @@ sample lists them out on the debug serial output.
 .. warning::
    In case when mount fails the device may get re-formatted to FAT FS.
    To disable this behaviour disable :kconfig:option:`CONFIG_FS_FATFS_MOUNT_MKFS` .
+
+Building and Running EXT2 samples
+*********************************
+
+Ext2 sample can be build for ``hifive_unmatched`` or ``bl5340_dvk_cpuapp``. Because
+FAT is default file system for this sample, additional flags must be passed to build
+the sample.
+
+.. zephyr-app-commands::
+   :zephyr-app: samples/subsys/fs/fs_sample
+   :board: hifive_unmatched
+   :gen-args: -DCONF_FILE=prj_ext.conf
+   :goals: build
+   :compact:
+
+A microSD card must be present in a microSD card slot of the board, for the sample to execute.
+After starting the sample a contents of a root directory should be printed on the console.

samples/subsys/fs/fs_sample/boards/hifive_unmatched.overlay

@@ -0,0 +1,20 @@
+/*
+ * Copyright (c) 2023 Antmicro
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+&spi2 {
+        status = "okay";
+
+        sdhc0: sdhc@0 {
+                compatible = "zephyr,sdhc-spi-slot";
+                reg = <0>;
+                status = "okay";
+                mmc {
+                    compatible = "zephyr,sdmmc-disk";
+                    status = "okay";
+                };
+                spi-max-frequency = <20000000>;
+        };
+};

samples/subsys/fs/fat_fs/boards/nrf52840dk_nrf52840.conf → samples/subsys/fs/fs_sample/boards/nrf52840dk_nrf52840.conf

@@ -9,4 +9,4 @@ CONFIG_DISK_DRIVER_FLASH=y
 # There may be no files on internal SoC flash, so this Kconfig
 # options has ben enabled to create some if listing does not
 # find in the first place.
-CONFIG_SAMPLE_FATFS_CREATE_SOME_ENTRIES=y
+CONFIG_FS_SAMPLE_CREATE_SOME_ENTRIES=y

samples/subsys/fs/fat_fs/boards/nrf52840dk_nrf52840_qspi.conf → samples/subsys/fs/fs_sample/boards/nrf52840dk_nrf52840_qspi.conf

@@ -12,4 +12,4 @@ CONFIG_DISK_DRIVER_FLASH=y
 # There may be no files on internal SoC flash, so this Kconfig
 # options has ben enabled to create some if listing does not
 # find in the first place.
-CONFIG_SAMPLE_FATFS_CREATE_SOME_ENTRIES=y
+CONFIG_FS_SAMPLE_CREATE_SOME_ENTRIES=y

samples/subsys/fs/fs_sample/prj_ext.conf

@@ -0,0 +1,20 @@
+# Copyright (c) 2023 Antmicro <www.antmicro.com>
+# SPDX-License-Identifier: Apache-2.0
+
+CONFIG_LOG=y
+CONFIG_LOG_MODE_IMMEDIATE=y
+
+CONFIG_MAIN_STACK_SIZE=2048
+
+CONFIG_FILE_SYSTEM=y
+CONFIG_FILE_SYSTEM_EXT2=y
+
+# Enable to allow formatting
+# CONFIG_FILE_SYSTEM_MKFS=y
+# CONFIG_TEST_RANDOM_GENERATOR=y
+
+CONFIG_DISK_ACCESS=y
+CONFIG_DISK_DRIVER_SDMMC=y
+
+# First block of first partition after GPT
+CONFIG_EXT2_DISK_STARTING_SECTOR=2082

samples/subsys/fs/fat_fs/sample.yaml → samples/subsys/fs/fs_sample/sample.yaml

@@ -1,5 +1,5 @@
 sample:
-  name: Fat filesystem sample
+  name: Filesystems sample
 common:
   tags: filesystem
   modules:
@@ -42,3 +42,6 @@ tests:
     filter: dt_compat_enabled("zephyr,sdmmc-disk")
     integration_platforms:
       - frdm_k64f
+  sample.filesystem.ext2:
+    extra_args: CONF_FILE="prj_ext.conf"
+    platform_allow: hifive_unmatched bl5340_dvk_cpuapp

samples/subsys/fs/fat_fs/src/main.c → samples/subsys/fs/fs_sample/src/main.c

@@ -1,6 +1,7 @@
 /*
  * Copyright (c) 2019 Tavish Naruka <tavishnaruka@gmail.com>
  * Copyright (c) 2023 Nordic Semiconductor ASA
+ * Copyright (c) 2023 Antmicro <www.antmicro.com>
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -12,16 +13,17 @@
 #include <zephyr/storage/disk_access.h>
 #include <zephyr/logging/log.h>
 #include <zephyr/fs/fs.h>
-#include <ff.h>
 
-LOG_MODULE_REGISTER(main);
+#if defined(CONFIG_FAT_FILESYSTEM_ELM)
+
+#include <ff.h>
 
+/*
+ *  Note the fatfs library is able to mount only strings inside _VOLUME_STRS
+ *  in ffconf.h
+ */
 #define DISK_DRIVE_NAME "SD"
 #define DISK_MOUNT_PT "/"DISK_DRIVE_NAME":"
-#define MAX_PATH 128
-#define SOME_FILE_NAME "some.dat"
-#define SOME_DIR_NAME "some"
-#define SOME_REQUIRED_LEN MAX(sizeof(SOME_FILE_NAME), sizeof(SOME_DIR_NAME))
 
 static FATFS fat_fs;
 /* mounting info */
@@ -30,8 +32,31 @@ static struct fs_mount_t mp = {
 	.fs_data = &fat_fs,
 };
 
+#elif defined(CONFIG_FILE_SYSTEM_EXT2)
+
+#include <zephyr/fs/ext2.h>
+
+#define DISK_DRIVE_NAME "SDMMC"
+#define DISK_MOUNT_PT "/ext"
+
+static struct fs_mount_t mp = {
+	.type = FS_EXT2,
+	.flags = FS_MOUNT_FLAG_NO_FORMAT,
+	.storage_dev = (void *)DISK_DRIVE_NAME,
+	.mnt_point = "/ext",
+};
+
+#endif
+
+LOG_MODULE_REGISTER(main);
+
+#define MAX_PATH 128
+#define SOME_FILE_NAME "some.dat"
+#define SOME_DIR_NAME "some"
+#define SOME_REQUIRED_LEN MAX(sizeof(SOME_FILE_NAME), sizeof(SOME_DIR_NAME))
+
 static int lsdir(const char *path);
-#ifdef CONFIG_SAMPLE_FATFS_CREATE_SOME_ENTRIES
+#ifdef CONFIG_FS_SAMPLE_CREATE_SOME_ENTRIES
 static bool create_some_entries(const char *base_path)
 {
 	char path[MAX_PATH];
@@ -71,10 +96,6 @@ static bool create_some_entries(const char *base_path)
 }
 #endif
 
-/*
-*  Note the fatfs library is able to mount only strings inside _VOLUME_STRS
-*  in ffconf.h
-*/
 static const char *disk_mount_pt = DISK_MOUNT_PT;
 
 int main(void)
@@ -113,10 +134,14 @@ int main(void)
 
 	int res = fs_mount(&mp);
 
+#if defined(CONFIG_FAT_FILESYSTEM_ELM)
 	if (res == FR_OK) {
+#else
+	if (res == 0) {
+#endif
 		printk("Disk mounted.\n");
 		if (lsdir(disk_mount_pt) == 0) {
-#ifdef CONFIG_SAMPLE_FATFS_CREATE_SOME_ENTRIES
+#ifdef CONFIG_FS_SAMPLE_CREATE_SOME_ENTRIES
 			if (create_some_entries(disk_mount_pt)) {
 				lsdir(disk_mount_pt);
 			}
@@ -126,6 +151,8 @@ int main(void)
 		printk("Error mounting disk.\n");
 	}
 
+	fs_unmount(&mp);
+
 	while (1) {
 		k_sleep(K_MSEC(1000));
 	}