2
0
mirror of https://github.com/edk2-porting/linux-next.git synced 2024-12-17 01:34:00 +08:00
linux-next/drivers/lguest
Rusty Russell cc6d4fbcef Introduce "hcall" pointer to indicate pending hypercall.
Currently we look at the "trapnum" to see if the Guest wants a
hypercall.  But once the hypercall is done we have to reset trapnum to
a bogus value, otherwise if we exit to userspace and return, we'd run
the same hypercall twice (that was a nasty bug to find!).

This has two main effects:

1) When Jes's patch changes the hypercall args to be a generic "struct
   hcall_args" we simply change the type of "lg->hcall".  It's set by
   arch code, so if it has to copy args or something it can do so, and
   point "hcall" into lg->arch somewhere.

2) Async hypercalls only get run when an actual hypercall is pending.
   This simplfies the code a little and is a more logical semantic.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2007-10-23 15:49:52 +10:00
..
x86 Introduce "hcall" pointer to indicate pending hypercall. 2007-10-23 15:49:52 +10:00
core.c Introduce "hcall" pointer to indicate pending hypercall. 2007-10-23 15:49:52 +10:00
hypercalls.c Introduce "hcall" pointer to indicate pending hypercall. 2007-10-23 15:49:52 +10:00
interrupts_and_traps.c Move i386 part of core.c to x86/core.c. 2007-10-23 15:49:51 +10:00
io.c Remove fixed limit on number of guests, and lguests array. 2007-10-23 15:49:51 +10:00
Kconfig Lguest currently depends on 32-bit x86, not just x86. 2007-10-23 15:49:48 +10:00
lg.h Introduce "hcall" pointer to indicate pending hypercall. 2007-10-23 15:49:52 +10:00
lguest_bus.c lguest_devices belongs in lguest_bus.c: it's not i386-specific. 2007-10-23 15:49:49 +10:00
lguest_user.c Remove fixed limit on number of guests, and lguests array. 2007-10-23 15:49:51 +10:00
Makefile Move i386 part of core.c to x86/core.c. 2007-10-23 15:49:51 +10:00
page_tables.c Introduce guest mem offset, static link example launcher 2007-10-23 15:49:50 +10:00
README lguest: documentation I: Preparation 2007-07-26 11:35:16 -07:00
segments.c Move i386 part of core.c to x86/core.c. 2007-10-23 15:49:51 +10:00

Welcome, friend reader, to lguest.

Lguest is an adventure, with you, the reader, as Hero.  I can't think of many
5000-line projects which offer both such capability and glimpses of future
potential; it is an exciting time to be delving into the source!

But be warned; this is an arduous journey of several hours or more!  And as we
know, all true Heroes are driven by a Noble Goal.  Thus I offer a Beer (or
equivalent) to anyone I meet who has completed this documentation.

So get comfortable and keep your wits about you (both quick and humorous).
Along your way to the Noble Goal, you will also gain masterly insight into
lguest, and hypervisors and x86 virtualization in general.

Our Quest is in seven parts: (best read with C highlighting turned on)

I) Preparation
	- In which our potential hero is flown quickly over the landscape for a
	  taste of its scope.  Suitable for the armchair coders and other such
	  persons of faint constitution.

II) Guest
	- Where we encounter the first tantalising wisps of code, and come to
	  understand the details of the life of a Guest kernel.

III) Drivers
	- Whereby the Guest finds its voice and become useful, and our
	  understanding of the Guest is completed.

IV) Launcher
	- Where we trace back to the creation of the Guest, and thus begin our
	  understanding of the Host.

V) Host
	- Where we master the Host code, through a long and tortuous journey.
	  Indeed, it is here that our hero is tested in the Bit of Despair.

VI) Switcher
	- Where our understanding of the intertwined nature of Guests and Hosts
	  is completed.

VII) Mastery
	- Where our fully fledged hero grapples with the Great Question:
	  "What next?"

make Preparation!
Rusty Russell.