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Diffstat (limited to 'drivers/lguest/hypercalls.c')
-rw-r--r--drivers/lguest/hypercalls.c304
1 files changed, 0 insertions, 304 deletions
diff --git a/drivers/lguest/hypercalls.c b/drivers/lguest/hypercalls.c
deleted file mode 100644
index 601f81c04873..000000000000
--- a/drivers/lguest/hypercalls.c
+++ /dev/null
@@ -1,304 +0,0 @@
-/*P:500
- * Just as userspace programs request kernel operations through a system
- * call, the Guest requests Host operations through a "hypercall". You might
- * notice this nomenclature doesn't really follow any logic, but the name has
- * been around for long enough that we're stuck with it. As you'd expect, this
- * code is basically a one big switch statement.
-:*/
-
-/* Copyright (C) 2006 Rusty Russell IBM Corporation
-
- This program is free software; you can redistribute it and/or modify
- it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 2 of the License, or
- (at your option) any later version.
-
- This program is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- GNU General Public License for more details.
-
- You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
-*/
-#include <linux/uaccess.h>
-#include <linux/syscalls.h>
-#include <linux/mm.h>
-#include <linux/ktime.h>
-#include <asm/page.h>
-#include <asm/pgtable.h>
-#include "lg.h"
-
-/*H:120
- * This is the core hypercall routine: where the Guest gets what it wants.
- * Or gets killed. Or, in the case of LHCALL_SHUTDOWN, both.
- */
-static void do_hcall(struct lg_cpu *cpu, struct hcall_args *args)
-{
- switch (args->arg0) {
- case LHCALL_FLUSH_ASYNC:
- /*
- * This call does nothing, except by breaking out of the Guest
- * it makes us process all the asynchronous hypercalls.
- */
- break;
- case LHCALL_SEND_INTERRUPTS:
- /*
- * This call does nothing too, but by breaking out of the Guest
- * it makes us process any pending interrupts.
- */
- break;
- case LHCALL_LGUEST_INIT:
- /*
- * You can't get here unless you're already initialized. Don't
- * do that.
- */
- kill_guest(cpu, "already have lguest_data");
- break;
- case LHCALL_SHUTDOWN: {
- char msg[128];
- /*
- * Shutdown is such a trivial hypercall that we do it in five
- * lines right here.
- *
- * If the lgread fails, it will call kill_guest() itself; the
- * kill_guest() with the message will be ignored.
- */
- __lgread(cpu, msg, args->arg1, sizeof(msg));
- msg[sizeof(msg)-1] = '\0';
- kill_guest(cpu, "CRASH: %s", msg);
- if (args->arg2 == LGUEST_SHUTDOWN_RESTART)
- cpu->lg->dead = ERR_PTR(-ERESTART);
- break;
- }
- case LHCALL_FLUSH_TLB:
- /* FLUSH_TLB comes in two flavors, depending on the argument: */
- if (args->arg1)
- guest_pagetable_clear_all(cpu);
- else
- guest_pagetable_flush_user(cpu);
- break;
-
- /*
- * All these calls simply pass the arguments through to the right
- * routines.
- */
- case LHCALL_NEW_PGTABLE:
- guest_new_pagetable(cpu, args->arg1);
- break;
- case LHCALL_SET_STACK:
- guest_set_stack(cpu, args->arg1, args->arg2, args->arg3);
- break;
- case LHCALL_SET_PTE:
-#ifdef CONFIG_X86_PAE
- guest_set_pte(cpu, args->arg1, args->arg2,
- __pte(args->arg3 | (u64)args->arg4 << 32));
-#else
- guest_set_pte(cpu, args->arg1, args->arg2, __pte(args->arg3));
-#endif
- break;
- case LHCALL_SET_PGD:
- guest_set_pgd(cpu->lg, args->arg1, args->arg2);
- break;
-#ifdef CONFIG_X86_PAE
- case LHCALL_SET_PMD:
- guest_set_pmd(cpu->lg, args->arg1, args->arg2);
- break;
-#endif
- case LHCALL_SET_CLOCKEVENT:
- guest_set_clockevent(cpu, args->arg1);
- break;
- case LHCALL_HALT:
- /* Similarly, this sets the halted flag for run_guest(). */
- cpu->halted = 1;
- break;
- default:
- /* It should be an architecture-specific hypercall. */
- if (lguest_arch_do_hcall(cpu, args))
- kill_guest(cpu, "Bad hypercall %li\n", args->arg0);
- }
-}
-
-/*H:124
- * Asynchronous hypercalls are easy: we just look in the array in the
- * Guest's "struct lguest_data" to see if any new ones are marked "ready".
- *
- * We are careful to do these in order: obviously we respect the order the
- * Guest put them in the ring, but we also promise the Guest that they will
- * happen before any normal hypercall (which is why we check this before
- * checking for a normal hcall).
- */
-static void do_async_hcalls(struct lg_cpu *cpu)
-{
- unsigned int i;
- u8 st[LHCALL_RING_SIZE];
-
- /* For simplicity, we copy the entire call status array in at once. */
- if (copy_from_user(&st, &cpu->lg->lguest_data->hcall_status, sizeof(st)))
- return;
-
- /* We process "struct lguest_data"s hcalls[] ring once. */
- for (i = 0; i < ARRAY_SIZE(st); i++) {
- struct hcall_args args;
- /*
- * We remember where we were up to from last time. This makes
- * sure that the hypercalls are done in the order the Guest
- * places them in the ring.
- */
- unsigned int n = cpu->next_hcall;
-
- /* 0xFF means there's no call here (yet). */
- if (st[n] == 0xFF)
- break;
-
- /*
- * OK, we have hypercall. Increment the "next_hcall" cursor,
- * and wrap back to 0 if we reach the end.
- */
- if (++cpu->next_hcall == LHCALL_RING_SIZE)
- cpu->next_hcall = 0;
-
- /*
- * Copy the hypercall arguments into a local copy of the
- * hcall_args struct.
- */
- if (copy_from_user(&args, &cpu->lg->lguest_data->hcalls[n],
- sizeof(struct hcall_args))) {
- kill_guest(cpu, "Fetching async hypercalls");
- break;
- }
-
- /* Do the hypercall, same as a normal one. */
- do_hcall(cpu, &args);
-
- /* Mark the hypercall done. */
- if (put_user(0xFF, &cpu->lg->lguest_data->hcall_status[n])) {
- kill_guest(cpu, "Writing result for async hypercall");
- break;
- }
-
- /*
- * Stop doing hypercalls if they want to notify the Launcher:
- * it needs to service this first.
- */
- if (cpu->pending.trap)
- break;
- }
-}
-
-/*
- * Last of all, we look at what happens first of all. The very first time the
- * Guest makes a hypercall, we end up here to set things up:
- */
-static void initialize(struct lg_cpu *cpu)
-{
- /*
- * You can't do anything until you're initialized. The Guest knows the
- * rules, so we're unforgiving here.
- */
- if (cpu->hcall->arg0 != LHCALL_LGUEST_INIT) {
- kill_guest(cpu, "hypercall %li before INIT", cpu->hcall->arg0);
- return;
- }
-
- if (lguest_arch_init_hypercalls(cpu))
- kill_guest(cpu, "bad guest page %p", cpu->lg->lguest_data);
-
- /*
- * The Guest tells us where we're not to deliver interrupts by putting
- * the instruction address into "struct lguest_data".
- */
- if (get_user(cpu->lg->noirq_iret, &cpu->lg->lguest_data->noirq_iret))
- kill_guest(cpu, "bad guest page %p", cpu->lg->lguest_data);
-
- /*
- * We write the current time into the Guest's data page once so it can
- * set its clock.
- */
- write_timestamp(cpu);
-
- /* page_tables.c will also do some setup. */
- page_table_guest_data_init(cpu);
-
- /*
- * This is the one case where the above accesses might have been the
- * first write to a Guest page. This may have caused a copy-on-write
- * fault, but the old page might be (read-only) in the Guest
- * pagetable.
- */
- guest_pagetable_clear_all(cpu);
-}
-/*:*/
-
-/*M:013
- * If a Guest reads from a page (so creates a mapping) that it has never
- * written to, and then the Launcher writes to it (ie. the output of a virtual
- * device), the Guest will still see the old page. In practice, this never
- * happens: why would the Guest read a page which it has never written to? But
- * a similar scenario might one day bite us, so it's worth mentioning.
- *
- * Note that if we used a shared anonymous mapping in the Launcher instead of
- * mapping /dev/zero private, we wouldn't worry about cop-on-write. And we
- * need that to switch the Launcher to processes (away from threads) anyway.
-:*/
-
-/*H:100
- * Hypercalls
- *
- * Remember from the Guest, hypercalls come in two flavors: normal and
- * asynchronous. This file handles both of types.
- */
-void do_hypercalls(struct lg_cpu *cpu)
-{
- /* Not initialized yet? This hypercall must do it. */
- if (unlikely(!cpu->lg->lguest_data)) {
- /* Set up the "struct lguest_data" */
- initialize(cpu);
- /* Hcall is done. */
- cpu->hcall = NULL;
- return;
- }
-
- /*
- * The Guest has initialized.
- *
- * Look in the hypercall ring for the async hypercalls:
- */
- do_async_hcalls(cpu);
-
- /*
- * If we stopped reading the hypercall ring because the Guest did a
- * NOTIFY to the Launcher, we want to return now. Otherwise we do
- * the hypercall.
- */
- if (!cpu->pending.trap) {
- do_hcall(cpu, cpu->hcall);
- /*
- * Tricky point: we reset the hcall pointer to mark the
- * hypercall as "done". We use the hcall pointer rather than
- * the trap number to indicate a hypercall is pending.
- * Normally it doesn't matter: the Guest will run again and
- * update the trap number before we come back here.
- *
- * However, if we are signalled or the Guest sends I/O to the
- * Launcher, the run_guest() loop will exit without running the
- * Guest. When it comes back it would try to re-run the
- * hypercall. Finding that bug sucked.
- */
- cpu->hcall = NULL;
- }
-}
-
-/*
- * This routine supplies the Guest with time: it's used for wallclock time at
- * initial boot and as a rough time source if the TSC isn't available.
- */
-void write_timestamp(struct lg_cpu *cpu)
-{
- struct timespec now;
- ktime_get_real_ts(&now);
- if (copy_to_user(&cpu->lg->lguest_data->time,
- &now, sizeof(struct timespec)))
- kill_guest(cpu, "Writing timestamp");
-}