lguest: makes special fields be per-vcpu

lguest struct have room for some fields, namely, cr2, ts, esp1
and ss1, that are not really guest-wide, but rather, vcpu-wide.

This patch puts it in the vcpu struct

Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This commit is contained in:
Glauber de Oliveira Costa 2008-01-07 11:05:35 -02:00 committed by Rusty Russell
parent 66686c2ab0
commit 4665ac8e28
5 changed files with 36 additions and 35 deletions

View file

@ -60,7 +60,7 @@ static void do_hcall(struct lg_cpu *cpu, struct hcall_args *args)
/* FLUSH_TLB comes in two flavors, depending on the
* argument: */
if (args->arg1)
guest_pagetable_clear_all(lg);
guest_pagetable_clear_all(cpu);
else
guest_pagetable_flush_user(lg);
break;
@ -68,10 +68,10 @@ static void do_hcall(struct lg_cpu *cpu, struct hcall_args *args)
/* All these calls simply pass the arguments through to the right
* routines. */
case LHCALL_NEW_PGTABLE:
guest_new_pagetable(lg, args->arg1);
guest_new_pagetable(cpu, args->arg1);
break;
case LHCALL_SET_STACK:
guest_set_stack(lg, args->arg1, args->arg2, args->arg3);
guest_set_stack(cpu, args->arg1, args->arg2, args->arg3);
break;
case LHCALL_SET_PTE:
guest_set_pte(lg, args->arg1, args->arg2, __pte(args->arg3));
@ -84,7 +84,7 @@ static void do_hcall(struct lg_cpu *cpu, struct hcall_args *args)
break;
case LHCALL_TS:
/* This sets the TS flag, as we saw used in run_guest(). */
lg->ts = args->arg1;
cpu->ts = args->arg1;
break;
case LHCALL_HALT:
/* Similarly, this sets the halted flag for run_guest(). */
@ -191,7 +191,7 @@ static void initialize(struct lg_cpu *cpu)
* 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(lg);
guest_pagetable_clear_all(cpu);
}
/*H:100

View file

@ -73,8 +73,8 @@ static void set_guest_interrupt(struct lg_cpu *cpu, u32 lo, u32 hi, int has_err)
if ((cpu->regs->ss&0x3) != GUEST_PL) {
/* The Guest told us their kernel stack with the SET_STACK
* hypercall: both the virtual address and the segment */
virtstack = lg->esp1;
ss = lg->ss1;
virtstack = cpu->esp1;
ss = cpu->ss1;
origstack = gstack = guest_pa(lg, virtstack);
/* We push the old stack segment and pointer onto the new
@ -311,10 +311,11 @@ static int direct_trap(unsigned int num)
* the Guest.
*
* Which is deeply unfair, because (literally!) it wasn't the Guests' fault. */
void pin_stack_pages(struct lguest *lg)
void pin_stack_pages(struct lg_cpu *cpu)
{
unsigned int i;
struct lguest *lg = cpu->lg;
/* Depending on the CONFIG_4KSTACKS option, the Guest can have one or
* two pages of stack space. */
for (i = 0; i < lg->stack_pages; i++)
@ -322,7 +323,7 @@ void pin_stack_pages(struct lguest *lg)
* start of the page after the kernel stack. Subtract one to
* get back onto the first stack page, and keep subtracting to
* get to the rest of the stack pages. */
pin_page(lg, lg->esp1 - 1 - i * PAGE_SIZE);
pin_page(lg, cpu->esp1 - 1 - i * PAGE_SIZE);
}
/* Direct traps also mean that we need to know whenever the Guest wants to use
@ -333,21 +334,21 @@ void pin_stack_pages(struct lguest *lg)
*
* In Linux each process has its own kernel stack, so this happens a lot: we
* change stacks on each context switch. */
void guest_set_stack(struct lguest *lg, u32 seg, u32 esp, unsigned int pages)
void guest_set_stack(struct lg_cpu *cpu, u32 seg, u32 esp, unsigned int pages)
{
/* You are not allowed have a stack segment with privilege level 0: bad
* Guest! */
if ((seg & 0x3) != GUEST_PL)
kill_guest(lg, "bad stack segment %i", seg);
kill_guest(cpu->lg, "bad stack segment %i", seg);
/* We only expect one or two stack pages. */
if (pages > 2)
kill_guest(lg, "bad stack pages %u", pages);
kill_guest(cpu->lg, "bad stack pages %u", pages);
/* Save where the stack is, and how many pages */
lg->ss1 = seg;
lg->esp1 = esp;
lg->stack_pages = pages;
cpu->ss1 = seg;
cpu->esp1 = esp;
cpu->lg->stack_pages = pages;
/* Make sure the new stack pages are mapped */
pin_stack_pages(lg);
pin_stack_pages(cpu);
}
/* All this reference to mapping stacks leads us neatly into the other complex

View file

@ -46,6 +46,11 @@ struct lg_cpu {
struct task_struct *tsk;
struct mm_struct *mm; /* == tsk->mm, but that becomes NULL on exit */
u32 cr2;
int ts;
u32 esp1;
u8 ss1;
/* At end of a page shared mapped over lguest_pages in guest. */
unsigned long regs_page;
struct lguest_regs *regs;
@ -80,10 +85,6 @@ struct lguest
* memory in the Launcher. */
void __user *mem_base;
unsigned long kernel_address;
u32 cr2;
int ts;
u32 esp1;
u8 ss1;
/* Bitmap of what has changed: see CHANGED_* above. */
int changed;
@ -141,8 +142,8 @@ void maybe_do_interrupt(struct lg_cpu *cpu);
int deliver_trap(struct lg_cpu *cpu, unsigned int num);
void load_guest_idt_entry(struct lg_cpu *cpu, unsigned int i,
u32 low, u32 hi);
void guest_set_stack(struct lguest *lg, u32 seg, u32 esp, unsigned int pages);
void pin_stack_pages(struct lguest *lg);
void guest_set_stack(struct lg_cpu *cpu, u32 seg, u32 esp, unsigned int pages);
void pin_stack_pages(struct lg_cpu *cpu);
void setup_default_idt_entries(struct lguest_ro_state *state,
const unsigned long *def);
void copy_traps(const struct lg_cpu *cpu, struct desc_struct *idt,
@ -164,9 +165,9 @@ void copy_gdt_tls(const struct lg_cpu *cpu, struct desc_struct *gdt);
/* page_tables.c: */
int init_guest_pagetable(struct lguest *lg, unsigned long pgtable);
void free_guest_pagetable(struct lguest *lg);
void guest_new_pagetable(struct lguest *lg, unsigned long pgtable);
void guest_new_pagetable(struct lg_cpu *cpu, unsigned long pgtable);
void guest_set_pmd(struct lguest *lg, unsigned long gpgdir, u32 i);
void guest_pagetable_clear_all(struct lguest *lg);
void guest_pagetable_clear_all(struct lg_cpu *cpu);
void guest_pagetable_flush_user(struct lguest *lg);
void guest_set_pte(struct lguest *lg, unsigned long gpgdir,
unsigned long vaddr, pte_t val);

View file

@ -432,9 +432,10 @@ static unsigned int new_pgdir(struct lguest *lg,
* Now we've seen all the page table setting and manipulation, let's see what
* what happens when the Guest changes page tables (ie. changes the top-level
* pgdir). This occurs on almost every context switch. */
void guest_new_pagetable(struct lguest *lg, unsigned long pgtable)
void guest_new_pagetable(struct lg_cpu *cpu, unsigned long pgtable)
{
int newpgdir, repin = 0;
struct lguest *lg = cpu->lg;
/* Look to see if we have this one already. */
newpgdir = find_pgdir(lg, pgtable);
@ -446,7 +447,7 @@ void guest_new_pagetable(struct lguest *lg, unsigned long pgtable)
lg->pgdidx = newpgdir;
/* If it was completely blank, we map in the Guest kernel stack */
if (repin)
pin_stack_pages(lg);
pin_stack_pages(cpu);
}
/*H:470 Finally, a routine which throws away everything: all PGD entries in all
@ -468,11 +469,11 @@ static void release_all_pagetables(struct lguest *lg)
* mapping. Since kernel mappings are in every page table, it's easiest to
* throw them all away. This traps the Guest in amber for a while as
* everything faults back in, but it's rare. */
void guest_pagetable_clear_all(struct lguest *lg)
void guest_pagetable_clear_all(struct lg_cpu *cpu)
{
release_all_pagetables(lg);
release_all_pagetables(cpu->lg);
/* We need the Guest kernel stack mapped again. */
pin_stack_pages(lg);
pin_stack_pages(cpu);
}
/*:*/
/*M:009 Since we throw away all mappings when a kernel mapping changes, our

View file

@ -95,8 +95,8 @@ static void copy_in_guest_info(struct lg_cpu *cpu, struct lguest_pages *pages)
/* Set up the two "TSS" members which tell the CPU what stack to use
* for traps which do directly into the Guest (ie. traps at privilege
* level 1). */
pages->state.guest_tss.esp1 = lg->esp1;
pages->state.guest_tss.ss1 = lg->ss1;
pages->state.guest_tss.esp1 = cpu->esp1;
pages->state.guest_tss.ss1 = cpu->ss1;
/* Copy direct-to-Guest trap entries. */
if (lg->changed & CHANGED_IDT)
@ -165,12 +165,10 @@ static void run_guest_once(struct lg_cpu *cpu, struct lguest_pages *pages)
* are disabled: we own the CPU. */
void lguest_arch_run_guest(struct lg_cpu *cpu)
{
struct lguest *lg = cpu->lg;
/* Remember the awfully-named TS bit? If the Guest has asked to set it
* we set it now, so we can trap and pass that trap to the Guest if it
* uses the FPU. */
if (lg->ts)
if (cpu->ts)
lguest_set_ts();
/* SYSENTER is an optimized way of doing system calls. We can't allow
@ -325,7 +323,7 @@ void lguest_arch_handle_trap(struct lg_cpu *cpu)
/* If the Guest doesn't want to know, we already restored the
* Floating Point Unit, so we just continue without telling
* it. */
if (!lg->ts)
if (!cpu->ts)
return;
break;
case 32 ... 255: