fs_write failed

[AydinyanNarek]

Hello,

Introdcution

I am using STM32 microcontroller and Zephyr 3.6.0 .
My application logger logs data to the Ram-FS, instead of flash memory. (Flash memory has a fixed count of write operations).
I have created Ram-FS(/etc and /tmp) using FALSH_SIMULATOR.
It looks like this.

/ {
	soc {
		flash_controller0: flash-controller@0 {
			compatible = "zephyr,sim-flash";
			reg = <0x00000000 DT_SIZE_K(64)>;

			#address-cells = <1>;
			#size-cells = <1>;
			erase-value = <0xff>;

			flash_sim0: flash_sim@0 {
				status = "okay";
				compatible = "soc-nv-flash";
				erase-block-size = <512>;
				write-block-size = <1>;
				reg = <0x00000000 DT_SIZE_K(64)>;

				partitions {
					compatible = "fixed-partitions";
					#address-cells = <1>;
					#size-cells = <1>;

					lfsram_partition0: partition@0 {
						label = "/tmp";
						reg = <0x00000000 0x00008000>;
					};

					lfsram_partition1: partition@1 {
						label = "/etc";
						reg = <0x00008000 0x00010000>;
					};
				};
			};
		};
	};
};

    fstab {
        compatible = "zephyr,fstab";
        lfs1: lfs1 {
			compatible = "zephyr,fstab,littlefs";
			read-size = <512>;
			prog-size = <512>;
			cache-size = <4096>;
			lookahead-size = <512>;
			block-cycles = <512>;
            partition = <&storage_partition>;
			mount-point = "/opt";
			automount;
        };

          lfsram0: lfsram0 {
	          compatible = "zephyr,fstab,littlefs";
	          mount-point = "/tmp";
	          partition = <&lfsram_partition0>;
	          automount;
	          read-size = <16>;
	          prog-size = <16>;
	          cache-size = <64>;
	          lookahead-size = <32>;
	          block-cycles = <512>;
          };
          
          lfsram1: lfsram1 {
	          compatible = "zephyr,fstab,littlefs";
	          mount-point = "/etc";
	          partition = <&lfsram_partition1>;
	          automount;
	          read-size = <16>;
	          prog-size = <16>;
	          cache-size = <64>;
	          lookahead-size = <32>;
	          block-cycles = <512>;
          };
    };

Notes.

1. /opt is using flash0 memory. (just skip this)
2. The combined log size is less than 10kb, which is less then the /tmp partition size
3. I am not writing 10kb log at once. I am doing small logs (max 512 bytes at a time).

Problems.

I am writing logs to /tmp directory using std::ofstream

1. The file remains empty Until I call a close function on the stream. (std::endl, std::flash, rdbuff(0,0,) ..etc doesn't help)
2. Using the open\close combination after each write helps the data to appear in the file, however when I am doing it multiple times(let's say more than 50) the fs_write returns error code -22 which is INVALID ARGUMENT ERROR and printing errno returns The Socket is not available.

Does someone have an idea about this ?