Commit 8d9b095b authored by Lee Jones's avatar Lee Jones Committed by Greg Kroah-Hartman
Browse files

samples: rust_misc_device: Provide an example C program to exercise functionality 



Here is the expected output (manually spliced together):

USERSPACE: Opening /dev/rust-misc-device for reading and writing
KERNEL: rust_misc_device: Opening Rust Misc Device Sample
USERSPACE: Calling Hello
KERNEL: rust_misc_device: IOCTLing Rust Misc Device Sample
KERNEL: rust_misc_device: -> Hello from the Rust Misc Device
USERSPACE: Fetching initial value
KERNEL: rust_misc_device: IOCTLing Rust Misc Device Sample
KERNEL: rust_misc_device: -> Copying data to userspace (value: 0)
USERSPACE: Submitting new value (1)
KERNEL: rust_misc_device: IOCTLing Rust Misc Device Sample
KERNEL: rust_misc_device: -> Copying data from userspace (value: 1)
USERSPACE: Fetching new value
KERNEL: rust_misc_device: IOCTLing Rust Misc Device Sample
KERNEL: rust_misc_device: -> Copying data to userspace (value: 1)
USERSPACE: Attempting to call in to an non-existent IOCTL
KERNEL: rust_misc_device: IOCTLing Rust Misc Device Sample
KERNEL: rust_misc_device: -> IOCTL not recognised: 20992
USERSPACE: ioctl: Succeeded to fail - this was expected: Inappropriate ioctl for device
USERSPACE: Closing /dev/rust-misc-device
KERNEL: rust_misc_device: Exiting the Rust Misc Device Sample
USERSPACE: Success

Signed-off-by: default avatarLee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20241213134715.601415-6-lee@kernel.org


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent ff9feb05

samples/rust/rust_misc_device.rs

+90 −0
Original line number Diff line number Diff line
@@ -4,6 +4,96 @@ 


//! Rust misc device sample.



/// Below is an example userspace C program that exercises this sample's functionality.

///

/// ```c

/// #include <stdio.h>

/// #include <stdlib.h>

/// #include <errno.h>

/// #include <fcntl.h>

/// #include <unistd.h>

/// #include <sys/ioctl.h>

///

/// #define RUST_MISC_DEV_FAIL _IO('|', 0)

/// #define RUST_MISC_DEV_HELLO _IO('|', 0x80)

/// #define RUST_MISC_DEV_GET_VALUE _IOR('|', 0x81, int)

/// #define RUST_MISC_DEV_SET_VALUE _IOW('|', 0x82, int)

///

/// int main() {

///   int value, new_value;

///   int fd, ret;

///

///   // Open the device file

///   printf("Opening /dev/rust-misc-device for reading and writing\n");

///   fd = open("/dev/rust-misc-device", O_RDWR);

///   if (fd < 0) {

///     perror("open");

///     return errno;

///   }

///

///   // Make call into driver to say "hello"

///   printf("Calling Hello\n");

///   ret = ioctl(fd, RUST_MISC_DEV_HELLO, NULL);

///   if (ret < 0) {

///     perror("ioctl: Failed to call into Hello");

///     close(fd);

///     return errno;

///   }

///

///   // Get initial value

///   printf("Fetching initial value\n");

///   ret = ioctl(fd, RUST_MISC_DEV_GET_VALUE, &value);

///   if (ret < 0) {

///     perror("ioctl: Failed to fetch the initial value");

///     close(fd);

///     return errno;

///   }

///

///   value++;

///

///   // Set value to something different

///   printf("Submitting new value (%d)\n", value);

///   ret = ioctl(fd, RUST_MISC_DEV_SET_VALUE, &value);

///   if (ret < 0) {

///     perror("ioctl: Failed to submit new value");

///     close(fd);

///     return errno;

///   }

///

///   // Ensure new value was applied

///   printf("Fetching new value\n");

///   ret = ioctl(fd, RUST_MISC_DEV_GET_VALUE, &new_value);

///   if (ret < 0) {

///     perror("ioctl: Failed to fetch the new value");

///     close(fd);

///     return errno;

///   }

///

///   if (value != new_value) {

///     printf("Failed: Committed and retrieved values are different (%d - %d)\n", value, new_value);

///     close(fd);

///     return -1;

///   }

///

///   // Call the unsuccessful ioctl

///   printf("Attempting to call in to an non-existent IOCTL\n");

///   ret = ioctl(fd, RUST_MISC_DEV_FAIL, NULL);

///   if (ret < 0) {

///     perror("ioctl: Succeeded to fail - this was expected");

///   } else {

///     printf("ioctl: Failed to fail\n");

///     close(fd);

///     return -1;

///   }

///

///   // Close the device file

///   printf("Closing /dev/rust-misc-device\n");

///   close(fd);

///

///   printf("Success\n");

///   return 0;

/// }

/// ```

use core::pin::Pin;



use kernel::{