Commit graph

151 commits

Author SHA1 Message Date
Robert Morris 86a1d4b295 sfence_vma after satp 2019-09-03 15:45:07 -04:00
Frans Kaashoek 510bcde894 Add major/minor/mkdev
Maybe apply this change to master
2019-08-23 19:41:53 -04:00
Frans Kaashoek d98ddadd79 Also release buffer on failed copyout 2019-08-20 12:46:56 -04:00
Frans Kaashoek 6005ef5a1c Release buffer also when copyin fails 2019-08-20 11:57:24 -04:00
Frans Kaashoek d9818b89e1 512 -> BSIZE 2019-08-20 11:56:56 -04:00
Frans Kaashoek a825f22cf8 Merge remote-tracking branch 'origin/master' into riscv 2019-08-19 19:27:29 -04:00
Frans Kaashoek 21ad8c76bc A few now unused DOC 2019-08-19 18:12:19 -04:00
Frans Kaashoek e10f797762 Merge remote-tracking branch 'origin/master' into riscv 2019-08-19 13:35:47 -04:00
Frans Kaashoek 2501560cd6 Cosmetic cleanup: fsinit reads sb and calls loginit. initialize icache
in main.c and don't make it disk specific; the icache is shared.  This
doesn't matter since we have only one disk, but conceptually cleaner
and maybe helpful to students for mount lab.
2019-08-18 14:35:11 -04:00
Frans Kaashoek e398a9815c Wrap state of disk driver in a struct so that it is easier to support
several disks (e.g., in a mount lab).
2019-08-12 07:20:32 -04:00
Robert Morris 0c10cbe829 syscall lab nits 2019-08-02 11:55:26 -04:00
Frans Kaashoek 62ece4b09e Merge branch 'riscv-bcache' into riscv 2019-08-01 15:46:50 -04:00
Robert Morris fb8a0099d4 fences for starting 2019-08-01 14:59:20 -04:00
Robert Morris d600026c3f cut ramdisk 2019-07-30 16:06:00 -04:00
Frans Kaashoek 848d1906e8 Track in buf if disk "owns" buffer 2019-07-30 12:53:19 -04:00
Frans Kaashoek f37a3e3964 Make pin/unpin explicit 2019-07-30 08:54:43 -04:00
Frans Kaashoek f1bb53c690 The driver should free descriptors, not interrupt handler. This
avoids handler freeing descriptors before driver sees that the request
has completed.
2019-07-30 08:13:03 -04:00
Frans Kaashoek 5304310452 Remove B_DIRTY
Use refcnt to pin blocks into the cache
Replace flags/B_VALID with a boolean field valid
Use info[id].status to signal completion of disk interrupt
Pass a read/write flag to virtio_disk_rw
2019-07-29 17:33:16 -04:00
Robert Morris 47b9cfee49 separate out timer init code for clarity 2019-07-28 13:16:49 -04:00
Robert Morris 1ec50c5848 xxx 2019-07-28 07:43:22 -04:00
Robert Morris 6507da772d argptr no longer needed, since copyin checks 2019-07-28 06:29:37 -04:00
Robert Morris 629faafa36 cleaner UART register interface 2019-07-27 06:44:24 -04:00
Robert Morris a33f60fea3 console/uart tweaks 2019-07-27 05:47:19 -04:00
Robert Morris cf48b24c03 beautify console.c 2019-07-27 04:15:06 -04:00
Robert Morris 281d450a08 split printf into a separate file, to make console.c more like a driver 2019-07-27 03:49:03 -04:00
Robert Morris cc1a303d09 fetchint isn't used any more 2019-07-26 12:34:06 -04:00
Robert Morris f0987d82dc ??? 2019-07-26 11:09:54 -04:00
Robert Morris c714e3e35c machinevec -> timervec 2019-07-26 10:17:02 -04:00
Robert Morris fa2e2e3c81 uservec before userret in trampoline, to match book and kernelvec 2019-07-26 09:38:22 -04:00
Robert Morris 8d30e21b59 Merge branch 'riscv' of g.csail.mit.edu:xv6-dev into riscv 2019-07-26 04:53:59 -04:00
Robert Morris ea95a6654c trampin -> uservec
trampout -> userret
2019-07-26 04:53:46 -04:00
Frans Kaashoek 47c9721d78 a few name changes in panic msg 2019-07-25 06:59:07 -04:00
Robert Morris 4e62de64cd fix an exit/exit deadlock -> one more locking protocol violation
increase timer rate from 1/second to 10/second
2019-07-25 06:30:49 -04:00
Robert Morris b19adf79f9 purge x86 stuff from defs.h 2019-07-25 05:37:35 -04:00
Robert Morris 5d5e4e065f comments for timer setup 2019-07-25 05:35:03 -04:00
Robert Morris 9a817bd134 rationalize some vm function names 2019-07-24 15:28:37 -04:00
Robert Morris da898a11b6 ??? 2019-07-24 14:40:13 -04:00
Robert Morris a77287e924 no more PAGEBREAK 2019-07-24 13:33:43 -04:00
Robert Morris b4f89bb529 ping-pong exercise 2019-07-24 10:39:05 -04:00
Robert Morris 8f6865d1f1 display assembly instructions, to help with first.tex exercise 2019-07-24 10:15:45 -04:00
Robert Morris 936afc6e1a mstart -> start 2019-07-23 14:31:12 -04:00
Robert Morris 54178ad94d simplify kernel mapping calls 2019-07-23 12:17:17 -04:00
Robert Morris 55bc96d419 a few core -> CPU
get rid of PDF generating support
2019-07-23 11:14:10 -04:00
Frans Kaashoek b8a31c494c one more TRAMPOLINE 2019-07-23 07:30:23 -04:00
Frans Kaashoek 6c78af4a57 fix mapkstack 2019-07-22 20:58:15 -04:00
Frans Kaashoek b2e9c8eea5 Clear U bit for second stack page so that it functions as a guard page 2019-07-22 15:38:08 -04:00
Robert Morris 38b430687c nit 2019-07-22 15:04:07 -04:00
Robert Morris 6b379e4707 -MD and TRAPFRAME 2019-07-22 14:54:40 -04:00
Frans Kaashoek 5eab649255 Allocate 2 pages per proc, with the top one unmapped.
The page below the last proc is unmapped by default (because the
kernel doesn't map anything right below the kernel stacks).
2019-07-22 14:30:45 -04:00
Frans Kaashoek c5d48db045 Merge branch 'riscv-kstack' into riscv 2019-07-22 13:32:33 -04:00
Robert Morris 328204d9cc not much 2019-07-20 18:51:31 -04:00
Robert Morris 06e49a58dc pi for pipe, rather than p, to avoid confusion with proc's p->lock 2019-07-20 17:07:20 -04:00
Robert Morris 3333665ab6 not much 2019-07-20 10:17:26 -04:00
Robert Morris 2418ac380c it's not clear that the release will always enable interrupts 2019-07-19 13:27:48 -04:00
Frans Kaashoek 06109901c9 x 2019-07-19 11:27:02 -04:00
Robert Morris dbd729b32d with per-proc locks, we don't need the intr_on() inside the loop. 2019-07-19 10:20:02 -04:00
Robert Morris 32168df609 no need to save/restore 14 2019-07-19 09:02:15 -04:00
Frans Kaashoek 9156632701 One way of supporting a guard page below kstack: allocate kstacks in
procinit() and map them high up (below TRAMPOLNE) with an empty
mapping below each stack.  Never free a kernel stack.

Another way would be to allocate and map them dynamically, but then we
need to reload page table when switching processes in scheduler()
and/or have a kernel pagetable per proc (if we want k->stack to be the
same virtual address in each process).

One gotcha: kernel addresses are not equal to physical addresses for
stack addresses.  A stack address must be translated if we need its
physical address (e.g., virtio passes a stack address to the disk).
2019-07-19 08:38:51 -04:00
Frans Kaashoek b924e44f06 Merge branch 'riscv' of g.csail.mit.edu:xv6-dev into riscv 2019-07-17 05:53:47 -04:00
Frans Kaashoek ce53416f49 Delete x86 comment 2019-07-17 05:53:34 -04:00
Robert Morris ebc3937209 conservatively call sfence.vma before every satp load. 2019-07-16 17:02:21 -04:00
Robert Morris 6bbc2b2245 cosmetic changes 2019-07-11 10:38:56 -04:00
Robert Morris 7797a38423 another test, to help with locking exercises 2019-07-11 05:41:59 -04:00
Robert Morris 4bc900e78b nits 2019-07-10 14:54:34 -04:00
Robert Morris 061e3be6f8 more comment cleanup 2019-07-10 10:13:08 -04:00
Robert Morris c0266a877a document which proc fields are protected by p->lock 2019-07-10 09:28:00 -04:00
Robert Morris 5eb1685700 have kill() lock before looking at p->pid
document wait()'s use of np->parent w/o holding lock.
2019-07-10 09:24:50 -04:00
Robert Morris 9981bb2270 tweak some comments. 2019-07-10 08:57:51 -04:00
Robert Morris 9d34838b4f holding p->lock all the way through state=RUNNABLE means we don't need EMBRYO 2019-07-08 11:11:00 -04:00
Robert Morris db72f3108f eliminate ptable. ptable.lock -> pid_lock. 2019-07-07 15:20:13 -04:00
Robert Morris 4ce3a5fa21 nits 2019-07-07 14:57:16 -04:00
Robert Morris c4f6a241cd avoid a double-lock of initproc->lock if child of init is reparenting 2019-07-07 07:03:28 -04:00
Frans Kaashoek dabbc348bc Maybe fix two races identified by rtm (thx!):
- during exit(), hold p's parent lock and p's lock across all changes
to p and its parent (e.g., reparenting and wakeup1).  the lock
ordering between concurrent exits of children, parent, and great
parent might work out because processes form a tree.

- in wakeup1() test and set p->state atomically by asking caller to
have p locked.

a correctness proof would be desirable.
2019-07-06 16:38:41 -04:00
Frans Kaashoek fab5e7c1de Make size in stat.h be a uint64
Supporting print long using %l (a bit of cheat)
Modify ls to print size using %l
We should probably update size in inode too.
2019-07-04 08:57:23 -04:00
Frans Kaashoek 6bfb078b14 x 2019-07-04 08:54:16 -04:00
Frans Kaashoek 47e69250d0 Simplify wakeup1 2019-07-03 15:38:30 -04:00
Frans Kaashoek cee830af24 Apply some corresponding bug fixes from wq branch here 2019-07-03 15:18:55 -04:00
Frans Kaashoek ccf299850b Remove some debugging code 2019-07-02 20:52:30 -04:00
Frans Kaashoek 26f306113a Fix a lost wakeup bug: the disk driver's wakeup() can run after the
reading process acquired p->lock and released virtio lock in sleep(),
but before the process had set p->status to SLEEPING, because the
wakeup tested p->status without holding p's lock.  Thus, wakeup can
complete without seeing any process SLEEPING and then p sets p->status
to SLEEPING.

Fix some other issues:

- Don't initialize proc lock in allocproc(), because freeproc() sets
np->state = UNUSED and allocproc() can choose np and calls initlock()
on the process's lock, releasing np's lock accidentally.  Move
initializing proc's lock to init.

- Protect nextpid using ptable.lock (and move into its own function)

Some clean up:
- Don't acquire p->lock when it p is used in a private way (e.g., exit()/grow()).
- Move find_runnable() back into scheduler().
2019-07-02 19:29:14 -04:00
Frans Kaashoek 1e4d7065d6 Merge branch 'riscv' into riscv-proc 2019-07-02 14:19:31 -04:00
Frans Kaashoek 84c759fc02 x 2019-07-02 14:09:38 -04:00
Frans Kaashoek 37ac6f8f4f Don't start processes at the end of the proc table 2019-07-02 13:55:52 -04:00
Frans Kaashoek da51735980 Avoid two cores selecting the same process to run 2019-07-02 13:40:33 -04:00
Robert Morris f59c1bf1d8 try to continue from walk() failing to allocate a page-table page 2019-07-02 11:45:06 -04:00
Robert Morris b27f275014 avoid allocproc() returning a struct proc with non-zero p->sz 2019-07-02 11:17:50 -04:00
Robert Morris 1540c8b15a COW tests 2019-07-02 11:04:35 -04:00
Frans Kaashoek 67702cf706 Checkpoint switching to per-process locks, in attempt clarify xv6's
locking plan, which is a difficult to understand because ptable lock
protects many invariants.  This implementation has a bug: once in a
while xv6 unlocks a proc lock that is locked by another core.
2019-07-02 09:14:47 -04:00
Robert Morris 40f1041a0a don't enable interrupts until done with sstatus, scause, &c 2019-07-02 05:20:11 -04:00
Robert Morris 535ac52efa oops, don't hold mycpu() result across intr_off() 2019-07-01 17:54:41 -04:00
Robert Morris abfe9999f4 have fork() fail, not panic, if not enough phys mem 2019-07-01 17:46:06 -04:00
Robert Morris 18e76a6c47 sbrk() returns a pointer, so it should be 64 bits 2019-07-01 17:01:50 -04:00
Robert Morris 9b99f00743 oops, don't hold mycpu() result across intr_off() 2019-07-01 14:15:18 -04:00
Robert Morris 0498bfd159 timer interrupt in the kernel -> yield 2019-07-01 13:46:11 -04:00
Frans Kaashoek 2c0338fe42 x 2019-07-01 08:28:14 -04:00
Frans Kaashoek af6c35e14b Introduce alloc3_desc and UsedArea to make code easier to read 2019-07-01 08:20:35 -04:00
Robert Morris a8305b7318 FD_DEVICE 2019-06-13 10:29:27 -04:00
Robert Morris 46744c4a13 for spinlocks, use gcc intrinsics, but say what they compile to 2019-06-13 10:00:50 -04:00
Robert Morris ca39672a30 clean up virtio code 2019-06-13 09:40:17 -04:00
Robert Morris 4adf016925 eliminate ramdisk 2019-06-13 06:57:38 -04:00
Robert Morris de9d72c908 virtio disk driver 2019-06-13 06:49:02 -04:00