Commit graph

141 commits

Author SHA1 Message Date
Robert Morris 3113643768 spinlocks using gcc intrinsics
push_off() / pop_off()
set up per-hart plic stuff so all harts get device interrupts
2019-06-05 14:05:46 -04:00
Robert Morris f1a727b971 start at support for multiple CPUs 2019-06-05 11:42:03 -04:00
Robert Morris 6eae1be755 push/pop all registers when handling interrupt from kernel 2019-06-03 15:23:12 -04:00
Robert Morris 7fd1f1eb0a exec compiles but argstr() doesn't work yet 2019-05-31 12:43:20 -04:00
Robert Morris 5d34fa2a48 -initrd fs.img, ramdisk.c, file system 2019-05-31 11:45:42 -04:00
Robert Morris 2ec1959fd1 fork/wait/exit work 2019-05-31 09:45:59 -04:00
Frans Kaashoek ab0db651af Checkpoint port of xv6 to x86-64. Passed usertests on 2 processors a few times.
The x86-64 doesn't just add two levels to page tables to support 64 bit
addresses, but is a different processor. For example, calling conventions,
system calls, and segmentation are different from 32-bit x86. Segmentation is
basically gone, but gs/fs in combination with MSRs can be used to hold a
per-core pointer. In general, x86-64 is more straightforward than 32-bit
x86. The port uses code from sv6 and the xv6 "rsc-amd64" branch.

A summary of the changes is as follows:

- Booting: switch to grub instead of xv6's bootloader (pass -kernel to qemu),
because xv6's boot loader doesn't understand 64bit ELF files.  And, we don't
care anymore about booting.

- Makefile: use -m64 instead of -m32 flag for gcc, delete boot loader, xv6.img,
bochs, and memfs. For now dont' use -O2, since usertests with -O2 is bigger than
MAXFILE!

- Update gdb.tmpl to be for i386 or x86-64

- Console/printf: use stdarg.h and treat 64-bit addresses different from ints
  (32-bit)

- Update elfhdr to be 64 bit

- entry.S/entryother.S: add code to switch to 64-bit mode: build a simple page
table in 32-bit mode before switching to 64-bit mode, share code for entering
boot processor and APs, and tweak boot gdt.  The boot gdt is the gdt that the
kernel proper also uses. (In 64-bit mode, the gdt/segmentation and task state
mostly disappear.)

- exec.c: fix passing argv (64-bit now instead of 32-bit).

- initcode.c: use syscall instead of int.

- kernel.ld: load kernel very high, in top terabyte.  64 bits is a lot of
address space!

- proc.c: initial return is through new syscall path instead of trapret.

- proc.h: update struct cpu to have some scratch space since syscall saves less
state than int, update struct context to reflect x86-64 calling conventions.

- swtch: simplify for x86-64 calling conventions.

- syscall: add fetcharg to handle x86-64 calling convetions (6 arguments are
passed through registers), and fetchaddr to read a 64-bit value from user space.

- sysfile: update to handle pointers from user space (e.g., sys_exec), which are
64 bits.

- trap.c: no special trap vector for sys calls, because x86-64 has a different
plan for system calls.

- trapasm: one plan for syscalls and one plan for traps (interrupt and
exceptions). On x86-64, the kernel is responsible for switching user/kernel
stacks. To do, xv6 keeps some scratch space in the cpu structure, and uses MSR
GS_KERN_BASE to point to the core's cpu structure (using swapgs).

- types.h: add uint64, and change pde_t to uint64

- usertests: exit() when fork fails, which helped in tracking down one of the
bugs in the switch from 32-bit to 64-bit

- vectors: update to make them 64 bits

- vm.c: use bootgdt in kernel too, program MSRs for syscalls and core-local
state (for swapgs), walk 4 levels in walkpgdir, add DEVSPACETOP, use task
segment to set kernel stack for interrupts (but simpler than in 32-bit mode),
add an extra argument to freevm (size of user part of address space) to avoid
checking all entries till KERNBASE (there are MANY TB before the top 1TB).

- x86: update trapframe to have 64-bit entries, which is what the processor
pushes on syscalls and traps.  simplify lgdt and lidt, using struct desctr,
which needs the gcc directives packed and aligned.

TODO:
- use int32 instead of int?
- simplify curproc(). xv6 has per-cpu state again, but this time it must have it.
- avoid repetition in walkpgdir
- fix validateint() in usertests.c
- fix bugs (e.g., observed one a case of entering kernel with invalid gs or proc
2018-09-23 08:35:30 -04:00
Frans Kaashoek 76d4005f9e thanks mtasm 2018-08-30 14:10:27 -04:00
Frans Kaashoek 8f63beaacb vectors.pl is executable and asks shell for perl 2018-08-30 13:36:07 -04:00
Frans Kaashoek 26108a3b99 thanks tyfkda 2018-08-30 13:27:57 -04:00
Frans Kaashoek 7f3528bcb3 x 2018-08-30 13:25:54 -04:00
Frans Kaashoek 0b6f4c08b9 x 2018-08-30 11:42:10 -04:00
Frans Kaashoek 4f14d8d1e5 Commit to running on an SMP (perhaps with only 1 core). Remove most code
from picirq.c and remove timer.c completely.  Update runoff.list.
2017-08-09 07:44:51 -04:00
Frans Kaashoek d57d37eb87 Thanks to Wolfgang Keller <nubok@users.noreply.github.com> 2017-01-30 20:09:54 -05:00
Antonio Gutierrez 1772853d39 Add support for qemu-system-x86_64 in 64bit hosts
As x86-64 is a superset of x86, we can use qemu-system-x86_64 to run
the OS image.

Signed-off-by: Antonio Gutierrez <chibby0ne@gmail.com>
2017-01-30 20:03:45 -05:00
Icenowy Zheng 91fd3470b0 Fixed broken build on newer gold linker with NaCl support
On platforms with NaCl support, ld.gold -V will return a "elf_i386_nacl" in
addition to "elf_i386", which will make the build fail.
2016-09-26 08:25:17 -04:00
Frans Kaashoek 6670d3b5e0 Straight replacement of B_BUSY with a sleeping lock. 2016-09-11 17:24:04 -04:00
Peter H. Froehlich 5faed8ba64 Fixed QEMU command line avoids raw image warning. 2016-08-18 14:30:30 -04:00
Peter H. Froehlich 216fdf846f Again, QEMU command line to avoid image warning. 2016-08-18 11:20:43 -04:00
Robert Morris 19f65413bd hold ptable.lock for the entire process creation
however, processes still modify their own p->* without locking
2016-08-13 03:44:13 -04:00
Frans Kaashoek ecb40fb19d coding style (per Jeremías Feltan <jeremias.feltan@gmail.com>) 2015-06-30 16:23:56 -04:00
Austin Clements 41f16c2183 Increase VM memory when running qemu-memfs
Presumably because of the pre-loaded file system, the default RAM is
insufficient when running kernelmemfs
2014-10-03 09:44:26 -04:00
Austin Clements 8e54196355 Make kernelmemfs depend on kernel.ld 2014-10-03 09:43:44 -04:00
Austin Clements 0dd991dd20 Fix kernelmemfs linking
Commit 9aa0337d introduced a linker script for linking the kernel image,
but only changed the kernel target to use it.  kernelmemfs was still
using the old linker command line arguments, which weren't sufficient.
2014-10-03 09:39:09 -04:00
Frans Kaashoek 053082fbed ggdb -> gdwarf-2 for gcc4.8 2014-09-23 07:39:32 -04:00
Frans Kaashoek 75dee1219f Oops (thanks David Lawrence) 2014-09-08 18:00:53 -04:00
Frans Kaashoek 86188d9d49 newer versions of qemu have different binary names (per Joel Nider <joel@nider.org>) 2014-07-31 11:15:15 -04:00
Cam Tenny 241c068066 Prevent extra rebuild of fs.img by keeping intermediate object files. 2012-10-24 18:52:40 -04:00
Frans Kaashoek cf57e525c1 Remove -m32 flag from native gcc compiler
But check that mkfs.c is building with LP64
2012-09-07 17:39:04 -04:00
Austin Clements 09b1909163 Re-alphabetize OBJS 2011-09-05 23:45:04 -04:00
Austin Clements b1c66ca899 Sync up clean and gitignore better 2011-09-05 15:21:40 -04:00
Austin Clements 68b5872716 kernel depends on kernel.ld 2011-09-04 15:19:43 -04:00
Austin Clements e33873067b Add QEMUEXTRA environment to add extra QEMU arguments, like in JOS 2011-09-04 15:19:33 -04:00
Austin Clements 215a9ce237 A few missed xv6.pdf dependencies 2011-09-02 16:36:08 -04:00
Austin Clements dd4438b4fe Nuke data.S, since we do have a custom linker script. 2011-09-02 14:51:55 -04:00
Frans Kaashoek 427958cb71 Update make clean 2011-08-15 20:32:04 -04:00
Frans Kaashoek a4b213cf49 Avoid "boot" in xv6 2011-08-15 20:11:13 -04:00
Frans Kaashoek c60a3551c2 Separate more clearly bootloader from xv6 by renaming multiboot.S to entry.S etc.
Maybe the string boot shouldn't appear in xv6 code?
2011-08-15 12:02:59 -04:00
Frans Kaashoek bd71a45046 Make AP processors boot using bootpgdir
Remove device mapping from bootpgdir
Remove unnecessary vmenable
Set CPUS back to 2 in Makefile
Passes all usertests
2011-08-11 12:25:10 -04:00
Frans Kaashoek 66ba8079c7 Use static page table for boot, mapping first 4Mbyte; no more segment trick
Allocate proper kernel page table immediately in main using boot allocator
Remove pginit
Simplify address space layout a tiny bit
More to come (e.g., superpages to simplify static table)
2011-08-09 21:37:35 -04:00
Frans Kaashoek b23d8329e7 Allow gas to use / as divide (instead of comment)
Maybe not necessary, but don't want to waste time figuring this out again
2011-08-09 16:09:15 -04:00
Frans Kaashoek 9aa0337dc1 Map kernel high
Very important to give qemu memory through PHYSTOP :(
2011-07-29 07:31:27 -04:00
Frans Kaashoek 13a96baefc Dirt simple logging
Passes usertests and stressfs
Seems to recover correctly in a number of simple cases
2011-07-27 20:35:46 -04:00
Austin Clements 97657d703f Add -fno-omit-frame-pointer to compile flags.
At some point between gcc 4.4 and 4.6, omitting the frame pointer
became default if any -O is specified.  getcallerpcs relies on the
frame pointer, so bring it back.
2011-06-24 14:22:19 -04:00
Russ Cox cf4b1ad90b xv6: formatting, cleanup, rev5 (take 2) 2011-02-19 21:17:55 -05:00
Russ Cox 89bfdd4db1 multiboot support and memory-only (no disk) kernel 2011-01-11 13:27:45 -05:00
Austin Clements 124fe7e457 Rev 4 2010-09-03 15:47:28 -04:00
Austin Clements 41c4bbb505 Make it easy to change the number of CPUs 2010-09-01 02:14:35 -04:00
Austin Clements 51e2a7b324 print depends on runoff.spec 2010-08-31 17:30:31 -04:00
Austin Clements 880ee18ab1 mkfs must be compiled 32-bit. Fix mkfs warnings 2010-08-31 15:11:10 -04:00