Fix Lfs to pass usertests

[travis1829]

• Added basic synchronization. 2c5ffeb
• Fixed bugs in InodeGuard::bmap_internal. 1acf937
• Added SegSumEntry::IndirectMap. de1c0d3

• and more

  Now, only the following usertests seem to always fail.

• manywrites
• bigwrite

We need to implement the segment cleaner to fix this.

[travis1829]

EDIT: Now, when tested with rustc 2022-03-09 and on release mode, only the following usertests fail and all others seem to always success.

• manywrites
• bigwrite : this one fails just because we didn't handle cases where we're out of disk blocks
• createtest
• iref

Also, note #613

[travis1829]

• Finally, it seems like almost all deadlock issues and bugs are resolved.
• Now, all usertests except manywrites, bigwrite and sharedfd always pass even on CPUS=3 (checked at least 10 times).
  • manywrites and bigwrite fail because we didn't implement the segment cleaner.
  • sharedfd : This one rarely fails on CPUS=3.
• Note that I tested this using rustc 2022-03-09 on debug mode (with CPUS=3).

[travis1829]

The failure of sharedfd seems to be by a disk error. An assertion in VirtioDisk::intr fails.

assert!(!info.inflight[id].status, "Disk::intr status");

Thread 3 hit Breakpoint 1, core::panicking::panic (expr=...)
    at /kaist-cp-home/taewoo.kim/.rustup/toolchains/nightly-2022-03-09-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/panicking.rs:48
48          panic_fmt(fmt::Arguments::new_v1(&[expr], &[]));
(gdb) bt
#0  core::panicking::panic (expr=...)
    at /kaist-cp-home/taewoo.kim/.rustup/toolchains/nightly-2022-03-09-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/panicking.rs:48
#1  0x0000000080014112 in rv6_kernel::virtio::virtio_disk::VirtioDisk::intr (self=..., kernel=...)
    at src/virtio/virtio_disk.rs:376
#2  0x000000008001318e in rv6_kernel::trap::<impl rv6_kernel::kernel::KernelRef>::handle_irq (self=..., 
    irq_type=<optimized out>) at src/trap.rs:232
#3  0x0000000080012fee in rv6_kernel::trap::<impl rv6_kernel::kernel::KernelRef>::kernel_trap (self=..., 
    trap_info=<optimized out>) at src/trap.rs:175
#4  0x00000000800301dc in rv6_kernel::trap::kerneltrap::{{closure}} (kref=...) at src/trap.rs:53
#5  rv6_kernel::kernel::kernel_ref::{{closure}} (k=...) at src/kernel.rs:47
#6  rv6_kernel::util::branded::Branded<T>::new (inner=..., f=...) at src/util/branded.rs:235
#7  rv6_kernel::kernel::kernel_ref (f=...) at src/kernel.rs:47
#8  rv6_kernel::trap::kerneltrap (arg=<optimized out>) at src/trap.rs:53
#9  0x0000000080034b24 in kernelvec ()
Backtrace stopped: frame did not save the PC

It seems like the error does not happen in Ufs, so seems like its a problem caused by the Lfs. EDIT: Fixed in 9df7a1d

[jeehoonkang]

bors r+

without actually reviewing this PR...

[kaist-cp-bors[bot]]

Build succeeded:

• ci