feat: add generic ioctl support

[zyuiop]

This PR adds an ioctl handler to file descriptor objects, such as sockets, and a helper to register any ioctl handler at a particular file system path.

Some Linux-specific crates communicate with the kernel via the use of an ioctl file. Support of ioctls may provide an easy path when porting such libraries to work with hermit, without increasing too much the size of the ABI for too specific features.

[mkroening]

We could use bitfield-struct for these bitfield types, which is already a transitive dependency.

We should link to the reference header (this one?) in the doc comments of this struct.

[zyuiop]

@mkroening it should be good now, I rebased and my new tests pass :)

edit: not sure what the failing test is nor why it fails...

[github-actions]

Benchmark Results

Details

Benchmark	Current: a8acdca	Previous: 2e23902	Performance Ratio
startup_benchmark Build Time	94.07 s	80.34 s	1.17 ❗
startup_benchmark File Size	0.78 MB	0.80 MB	0.98 ❗
Startup Time - 1 core	0.76 s (±0.01 s)	0.75 s (±0.02 s)	1.02
Startup Time - 2 cores	0.76 s (±0.01 s)	0.74 s (±0.02 s)	1.03 ❗
Startup Time - 4 cores	0.77 s (±0.02 s)	0.74 s (±0.02 s)	1.03
multithreaded_benchmark Build Time	93.81 s	82.11 s	1.14 ❗
multithreaded_benchmark File Size	0.87 MB	0.86 MB	1.02 ❗
Multithreaded Pi Efficiency - 2 Threads	66.58 % (±5.34 %)	85.89 % (±6.61 %)	0.78 ❗
Multithreaded Pi Efficiency - 4 Threads	40.07 % (±2.83 %)	43.43 % (±2.56 %)	0.92
Multithreaded Pi Efficiency - 8 Threads	19.63 % (±1.09 %)	25.76 % (±1.53 %)	0.76 ❗
micro_benchmarks Build Time	221.48 s	80.40 s	2.75 ❗
micro_benchmarks File Size	0.87 MB	0.86 MB	1.01 ❗
Scheduling time - 1 thread	179.75 ticks (±31.06 ticks)	62.65 ticks (±4.06 ticks)	2.87 ❗
Scheduling time - 2 threads	109.96 ticks (±25.41 ticks)	34.08 ticks (±4.10 ticks)	3.23 ❗
Micro - Time for syscall (getpid)	11.17 ticks (±5.54 ticks)	3.45 ticks (±0.58 ticks)	3.24 ❗
Memcpy speed - (built_in) block size 4096	57557.90 MByte/s (±41154.11 MByte/s)	82448.38 MByte/s (±56997.13 MByte/s)	0.70
Memcpy speed - (built_in) block size 1048576	14971.11 MByte/s (±12501.57 MByte/s)	30585.98 MByte/s (±24707.84 MByte/s)	0.49
Memcpy speed - (built_in) block size 16777216	12451.95 MByte/s (±10357.72 MByte/s)	26340.06 MByte/s (±21720.96 MByte/s)	0.47
Memset speed - (built_in) block size 4096	57856.26 MByte/s (±41392.11 MByte/s)	82292.76 MByte/s (±56891.50 MByte/s)	0.70
Memset speed - (built_in) block size 1048576	15477.44 MByte/s (±12813.51 MByte/s)	31323.85 MByte/s (±25145.86 MByte/s)	0.49
Memset speed - (built_in) block size 16777216	12863.83 MByte/s (±10633.52 MByte/s)	27104.68 MByte/s (±22209.94 MByte/s)	0.47
Memcpy speed - (rust) block size 4096	55364.83 MByte/s (±39372.33 MByte/s)	74097.96 MByte/s (±51811.44 MByte/s)	0.75
Memcpy speed - (rust) block size 1048576	15894.76 MByte/s (±14336.71 MByte/s)	30361.60 MByte/s (±24602.37 MByte/s)	0.52
Memcpy speed - (rust) block size 16777216	13139.34 MByte/s (±11364.41 MByte/s)	27625.34 MByte/s (±22806.88 MByte/s)	0.48
Memset speed - (rust) block size 4096	55707.39 MByte/s (±39578.86 MByte/s)	74373.47 MByte/s (±51976.48 MByte/s)	0.75
Memset speed - (rust) block size 1048576	16143.41 MByte/s (±14437.08 MByte/s)	31110.89 MByte/s (±25033.24 MByte/s)	0.52
Memset speed - (rust) block size 16777216	13427.19 MByte/s (±11501.35 MByte/s)	28386.93 MByte/s (±23265.03 MByte/s)	0.47
alloc_benchmarks Build Time	217.95 s	74.76 s	2.92 ❗
alloc_benchmarks File Size	0.86 MB	0.87 MB	0.98 ❗
Allocations - Allocation success	91.38 %	91.31 %	1.00 ❗
Allocations - Deallocation success	100.00 %	100.00 %	1
Allocations - Pre-fail Allocations	61.60 %	61.44 %	1.00 ❗
Allocations - Average Allocation time	24291.22 Ticks (±1619.55 Ticks)	5860.58 Ticks (±98.43 Ticks)	4.14 ❗
Allocations - Average Allocation time (no fail)	25162.60 Ticks (±1608.31 Ticks)	6554.81 Ticks (±92.86 Ticks)	3.84 ❗
Allocations - Average Deallocation time	7248.86 Ticks (±1812.81 Ticks)	1805.01 Ticks (±250.35 Ticks)	4.02 ❗
mutex_benchmark Build Time	212.09 s	79.82 s	2.66 ❗
mutex_benchmark File Size	0.87 MB	0.86 MB	1.02 ❗
Mutex Stress Test Average Time per Iteration - 1 Threads	34.48 ns (±7.52 ns)	12.10 ns (±0.41 ns)	2.85 ❗
Mutex Stress Test Average Time per Iteration - 2 Threads	31.20 ns (±8.66 ns)	40.26 ns (±1.68 ns)	0.77 ❗

This comment was automatically generated by workflow using github-action-benchmark.

[mkroening]

edit: not sure what the failing test is nor why it fails...

Firecracker is a bit flaky on CI nowadays, unfortunately.

[mkroening]

This looks good to me and I am personally fine with using ioctl for this.

@stlankes, @jounathaen, are you fine with us pivoting to ioctl for controlling drivers?

[jounathaen]

I'm not a fan of "pivoting to ioctl for controlling drivers", but we can merge it for enhanced compatibility. I'd like to see a feature flag for ioctls, but this can be added later once we have researched the impacts of this. (We should create an issue for this)

[zyuiop]

Check if we can remove this change to preserve the ABI

[zyuiop]

I have rebased the PR, in case there is still some interest for this!