aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/lguest
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2009-06-12 09:32:26 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2009-06-12 09:32:26 -0700
commit7f3591cfacf2d79c4f42238e46c7d053da8e020d (patch)
treef2e9ed7b6b0bc176facaa49846734790023a6b16 /drivers/lguest
parent16ffc3eeaa00d513b0076b7b2b96419f28acc912 (diff)
parentd1f0132e76a11b05167313c606a853953f416081 (diff)
downloadkernel_samsung_smdk4412-7f3591cfacf2d79c4f42238e46c7d053da8e020d.zip
kernel_samsung_smdk4412-7f3591cfacf2d79c4f42238e46c7d053da8e020d.tar.gz
kernel_samsung_smdk4412-7f3591cfacf2d79c4f42238e46c7d053da8e020d.tar.bz2
Merge git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-lguest
* git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-lguest: (31 commits) lguest: add support for indirect ring entries lguest: suppress notifications in example Launcher lguest: try to batch interrupts on network receive lguest: avoid sending interrupts to Guest when no activity occurs. lguest: implement deferred interrupts in example Launcher lguest: remove obsolete LHREQ_BREAK call lguest: have example Launcher service all devices in separate threads lguest: use eventfds for device notification eventfd: export eventfd_signal and eventfd_fget for lguest lguest: allow any process to send interrupts lguest: PAE fixes lguest: PAE support lguest: Add support for kvm_hypercall4() lguest: replace hypercall name LHCALL_SET_PMD with LHCALL_SET_PGD lguest: use native_set_* macros, which properly handle 64-bit entries when PAE is activated lguest: map switcher with executable page table entries lguest: fix writev returning short on console output lguest: clean up length-used value in example launcher lguest: Segment selectors are 16-bit long. Fix lg_cpu.ss1 definition. lguest: beyond ARRAY_SIZE of cpu->arch.gdt ...
Diffstat (limited to 'drivers/lguest')
-rw-r--r--drivers/lguest/Kconfig2
-rw-r--r--drivers/lguest/core.c30
-rw-r--r--drivers/lguest/hypercalls.c14
-rw-r--r--drivers/lguest/interrupts_and_traps.c57
-rw-r--r--drivers/lguest/lg.h28
-rw-r--r--drivers/lguest/lguest_user.c127
-rw-r--r--drivers/lguest/page_tables.c396
-rw-r--r--drivers/lguest/segments.c2
8 files changed, 531 insertions, 125 deletions
diff --git a/drivers/lguest/Kconfig b/drivers/lguest/Kconfig
index a3d3cba..0aaa059 100644
--- a/drivers/lguest/Kconfig
+++ b/drivers/lguest/Kconfig
@@ -1,6 +1,6 @@
config LGUEST
tristate "Linux hypervisor example code"
- depends on X86_32 && EXPERIMENTAL && !X86_PAE && FUTEX
+ depends on X86_32 && EXPERIMENTAL && EVENTFD
select HVC_DRIVER
---help---
This is a very simple module which allows you to run
diff --git a/drivers/lguest/core.c b/drivers/lguest/core.c
index 4845fb3..a6974e9 100644
--- a/drivers/lguest/core.c
+++ b/drivers/lguest/core.c
@@ -95,7 +95,7 @@ static __init int map_switcher(void)
* array of struct pages. It increments that pointer, but we don't
* care. */
pagep = switcher_page;
- err = map_vm_area(switcher_vma, PAGE_KERNEL, &pagep);
+ err = map_vm_area(switcher_vma, PAGE_KERNEL_EXEC, &pagep);
if (err) {
printk("lguest: map_vm_area failed: %i\n", err);
goto free_vma;
@@ -188,6 +188,9 @@ int run_guest(struct lg_cpu *cpu, unsigned long __user *user)
{
/* We stop running once the Guest is dead. */
while (!cpu->lg->dead) {
+ unsigned int irq;
+ bool more;
+
/* First we run any hypercalls the Guest wants done. */
if (cpu->hcall)
do_hypercalls(cpu);
@@ -195,23 +198,23 @@ int run_guest(struct lg_cpu *cpu, unsigned long __user *user)
/* It's possible the Guest did a NOTIFY hypercall to the
* Launcher, in which case we return from the read() now. */
if (cpu->pending_notify) {
- if (put_user(cpu->pending_notify, user))
- return -EFAULT;
- return sizeof(cpu->pending_notify);
+ if (!send_notify_to_eventfd(cpu)) {
+ if (put_user(cpu->pending_notify, user))
+ return -EFAULT;
+ return sizeof(cpu->pending_notify);
+ }
}
/* Check for signals */
if (signal_pending(current))
return -ERESTARTSYS;
- /* If Waker set break_out, return to Launcher. */
- if (cpu->break_out)
- return -EAGAIN;
-
/* Check if there are any interrupts which can be delivered now:
* if so, this sets up the hander to be executed when we next
* run the Guest. */
- maybe_do_interrupt(cpu);
+ irq = interrupt_pending(cpu, &more);
+ if (irq < LGUEST_IRQS)
+ try_deliver_interrupt(cpu, irq, more);
/* All long-lived kernel loops need to check with this horrible
* thing called the freezer. If the Host is trying to suspend,
@@ -224,10 +227,15 @@ int run_guest(struct lg_cpu *cpu, unsigned long __user *user)
break;
/* If the Guest asked to be stopped, we sleep. The Guest's
- * clock timer or LHREQ_BREAK from the Waker will wake us. */
+ * clock timer will wake us. */
if (cpu->halted) {
set_current_state(TASK_INTERRUPTIBLE);
- schedule();
+ /* Just before we sleep, make sure no interrupt snuck in
+ * which we should be doing. */
+ if (interrupt_pending(cpu, &more) < LGUEST_IRQS)
+ set_current_state(TASK_RUNNING);
+ else
+ schedule();
continue;
}
diff --git a/drivers/lguest/hypercalls.c b/drivers/lguest/hypercalls.c
index 54d66f0..c29ffa1 100644
--- a/drivers/lguest/hypercalls.c
+++ b/drivers/lguest/hypercalls.c
@@ -37,6 +37,10 @@ static void do_hcall(struct lg_cpu *cpu, struct hcall_args *args)
/* 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. */
@@ -73,11 +77,21 @@ static void do_hcall(struct lg_cpu *cpu, struct hcall_args *args)
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;
diff --git a/drivers/lguest/interrupts_and_traps.c b/drivers/lguest/interrupts_and_traps.c
index 6e99adb..0e9067b 100644
--- a/drivers/lguest/interrupts_and_traps.c
+++ b/drivers/lguest/interrupts_and_traps.c
@@ -128,30 +128,39 @@ static void set_guest_interrupt(struct lg_cpu *cpu, u32 lo, u32 hi,
/*H:205
* Virtual Interrupts.
*
- * maybe_do_interrupt() gets called before every entry to the Guest, to see if
- * we should divert the Guest to running an interrupt handler. */
-void maybe_do_interrupt(struct lg_cpu *cpu)
+ * interrupt_pending() returns the first pending interrupt which isn't blocked
+ * by the Guest. It is called before every entry to the Guest, and just before
+ * we go to sleep when the Guest has halted itself. */
+unsigned int interrupt_pending(struct lg_cpu *cpu, bool *more)
{
unsigned int irq;
DECLARE_BITMAP(blk, LGUEST_IRQS);
- struct desc_struct *idt;
/* If the Guest hasn't even initialized yet, we can do nothing. */
if (!cpu->lg->lguest_data)
- return;
+ return LGUEST_IRQS;
/* Take our "irqs_pending" array and remove any interrupts the Guest
* wants blocked: the result ends up in "blk". */
if (copy_from_user(&blk, cpu->lg->lguest_data->blocked_interrupts,
sizeof(blk)))
- return;
+ return LGUEST_IRQS;
bitmap_andnot(blk, cpu->irqs_pending, blk, LGUEST_IRQS);
/* Find the first interrupt. */
irq = find_first_bit(blk, LGUEST_IRQS);
- /* None? Nothing to do */
- if (irq >= LGUEST_IRQS)
- return;
+ *more = find_next_bit(blk, LGUEST_IRQS, irq+1);
+
+ return irq;
+}
+
+/* This actually diverts the Guest to running an interrupt handler, once an
+ * interrupt has been identified by interrupt_pending(). */
+void try_deliver_interrupt(struct lg_cpu *cpu, unsigned int irq, bool more)
+{
+ struct desc_struct *idt;
+
+ BUG_ON(irq >= LGUEST_IRQS);
/* They may be in the middle of an iret, where they asked us never to
* deliver interrupts. */
@@ -170,8 +179,12 @@ void maybe_do_interrupt(struct lg_cpu *cpu)
u32 irq_enabled;
if (get_user(irq_enabled, &cpu->lg->lguest_data->irq_enabled))
irq_enabled = 0;
- if (!irq_enabled)
+ if (!irq_enabled) {
+ /* Make sure they know an IRQ is pending. */
+ put_user(X86_EFLAGS_IF,
+ &cpu->lg->lguest_data->irq_pending);
return;
+ }
}
/* Look at the IDT entry the Guest gave us for this interrupt. The
@@ -194,6 +207,25 @@ void maybe_do_interrupt(struct lg_cpu *cpu)
* here is a compromise which means at least it gets updated every
* timer interrupt. */
write_timestamp(cpu);
+
+ /* If there are no other interrupts we want to deliver, clear
+ * the pending flag. */
+ if (!more)
+ put_user(0, &cpu->lg->lguest_data->irq_pending);
+}
+
+/* And this is the routine when we want to set an interrupt for the Guest. */
+void set_interrupt(struct lg_cpu *cpu, unsigned int irq)
+{
+ /* Next time the Guest runs, the core code will see if it can deliver
+ * this interrupt. */
+ set_bit(irq, cpu->irqs_pending);
+
+ /* Make sure it sees it; it might be asleep (eg. halted), or
+ * running the Guest right now, in which case kick_process()
+ * will knock it out. */
+ if (!wake_up_process(cpu->tsk))
+ kick_process(cpu->tsk);
}
/*:*/
@@ -510,10 +542,7 @@ static enum hrtimer_restart clockdev_fn(struct hrtimer *timer)
struct lg_cpu *cpu = container_of(timer, struct lg_cpu, hrt);
/* Remember the first interrupt is the timer interrupt. */
- set_bit(0, cpu->irqs_pending);
- /* If the Guest is actually stopped, we need to wake it up. */
- if (cpu->halted)
- wake_up_process(cpu->tsk);
+ set_interrupt(cpu, 0);
return HRTIMER_NORESTART;
}
diff --git a/drivers/lguest/lg.h b/drivers/lguest/lg.h
index af92a17..d4e8979 100644
--- a/drivers/lguest/lg.h
+++ b/drivers/lguest/lg.h
@@ -49,7 +49,7 @@ struct lg_cpu {
u32 cr2;
int ts;
u32 esp1;
- u8 ss1;
+ u16 ss1;
/* Bitmap of what has changed: see CHANGED_* above. */
int changed;
@@ -71,9 +71,7 @@ struct lg_cpu {
/* Virtual clock device */
struct hrtimer hrt;
- /* Do we need to stop what we're doing and return to userspace? */
- int break_out;
- wait_queue_head_t break_wq;
+ /* Did the Guest tell us to halt? */
int halted;
/* Pending virtual interrupts */
@@ -82,6 +80,16 @@ struct lg_cpu {
struct lg_cpu_arch arch;
};
+struct lg_eventfd {
+ unsigned long addr;
+ struct file *event;
+};
+
+struct lg_eventfd_map {
+ unsigned int num;
+ struct lg_eventfd map[];
+};
+
/* The private info the thread maintains about the guest. */
struct lguest
{
@@ -102,6 +110,8 @@ struct lguest
unsigned int stack_pages;
u32 tsc_khz;
+ struct lg_eventfd_map *eventfds;
+
/* Dead? */
const char *dead;
};
@@ -137,9 +147,13 @@ int run_guest(struct lg_cpu *cpu, unsigned long __user *user);
* in the kernel. */
#define pgd_flags(x) (pgd_val(x) & ~PAGE_MASK)
#define pgd_pfn(x) (pgd_val(x) >> PAGE_SHIFT)
+#define pmd_flags(x) (pmd_val(x) & ~PAGE_MASK)
+#define pmd_pfn(x) (pmd_val(x) >> PAGE_SHIFT)
/* interrupts_and_traps.c: */
-void maybe_do_interrupt(struct lg_cpu *cpu);
+unsigned int interrupt_pending(struct lg_cpu *cpu, bool *more);
+void try_deliver_interrupt(struct lg_cpu *cpu, unsigned int irq, bool more);
+void set_interrupt(struct lg_cpu *cpu, unsigned int irq);
bool 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);
@@ -150,6 +164,7 @@ void setup_default_idt_entries(struct lguest_ro_state *state,
void copy_traps(const struct lg_cpu *cpu, struct desc_struct *idt,
const unsigned long *def);
void guest_set_clockevent(struct lg_cpu *cpu, unsigned long delta);
+bool send_notify_to_eventfd(struct lg_cpu *cpu);
void init_clockdev(struct lg_cpu *cpu);
bool check_syscall_vector(struct lguest *lg);
int init_interrupts(void);
@@ -168,7 +183,10 @@ void copy_gdt_tls(const struct lg_cpu *cpu, struct desc_struct *gdt);
int init_guest_pagetable(struct lguest *lg);
void free_guest_pagetable(struct lguest *lg);
void guest_new_pagetable(struct lg_cpu *cpu, unsigned long pgtable);
+void guest_set_pgd(struct lguest *lg, unsigned long gpgdir, u32 i);
+#ifdef CONFIG_X86_PAE
void guest_set_pmd(struct lguest *lg, unsigned long gpgdir, u32 i);
+#endif
void guest_pagetable_clear_all(struct lg_cpu *cpu);
void guest_pagetable_flush_user(struct lg_cpu *cpu);
void guest_set_pte(struct lg_cpu *cpu, unsigned long gpgdir,
diff --git a/drivers/lguest/lguest_user.c b/drivers/lguest/lguest_user.c
index b8ee103..32e2971 100644
--- a/drivers/lguest/lguest_user.c
+++ b/drivers/lguest/lguest_user.c
@@ -7,32 +7,83 @@
#include <linux/miscdevice.h>
#include <linux/fs.h>
#include <linux/sched.h>
+#include <linux/eventfd.h>
+#include <linux/file.h>
#include "lg.h"
-/*L:055 When something happens, the Waker process needs a way to stop the
- * kernel running the Guest and return to the Launcher. So the Waker writes
- * LHREQ_BREAK and the value "1" to /dev/lguest to do this. Once the Launcher
- * has done whatever needs attention, it writes LHREQ_BREAK and "0" to release
- * the Waker. */
-static int break_guest_out(struct lg_cpu *cpu, const unsigned long __user*input)
+bool send_notify_to_eventfd(struct lg_cpu *cpu)
{
- unsigned long on;
+ unsigned int i;
+ struct lg_eventfd_map *map;
+
+ /* lg->eventfds is RCU-protected */
+ rcu_read_lock();
+ map = rcu_dereference(cpu->lg->eventfds);
+ for (i = 0; i < map->num; i++) {
+ if (map->map[i].addr == cpu->pending_notify) {
+ eventfd_signal(map->map[i].event, 1);
+ cpu->pending_notify = 0;
+ break;
+ }
+ }
+ rcu_read_unlock();
+ return cpu->pending_notify == 0;
+}
- /* Fetch whether they're turning break on or off. */
- if (get_user(on, input) != 0)
- return -EFAULT;
+static int add_eventfd(struct lguest *lg, unsigned long addr, int fd)
+{
+ struct lg_eventfd_map *new, *old = lg->eventfds;
- if (on) {
- cpu->break_out = 1;
- /* Pop it out of the Guest (may be running on different CPU) */
- wake_up_process(cpu->tsk);
- /* Wait for them to reset it */
- return wait_event_interruptible(cpu->break_wq, !cpu->break_out);
- } else {
- cpu->break_out = 0;
- wake_up(&cpu->break_wq);
- return 0;
+ if (!addr)
+ return -EINVAL;
+
+ /* Replace the old array with the new one, carefully: others can
+ * be accessing it at the same time */
+ new = kmalloc(sizeof(*new) + sizeof(new->map[0]) * (old->num + 1),
+ GFP_KERNEL);
+ if (!new)
+ return -ENOMEM;
+
+ /* First make identical copy. */
+ memcpy(new->map, old->map, sizeof(old->map[0]) * old->num);
+ new->num = old->num;
+
+ /* Now append new entry. */
+ new->map[new->num].addr = addr;
+ new->map[new->num].event = eventfd_fget(fd);
+ if (IS_ERR(new->map[new->num].event)) {
+ kfree(new);
+ return PTR_ERR(new->map[new->num].event);
}
+ new->num++;
+
+ /* Now put new one in place. */
+ rcu_assign_pointer(lg->eventfds, new);
+
+ /* We're not in a big hurry. Wait until noone's looking at old
+ * version, then delete it. */
+ synchronize_rcu();
+ kfree(old);
+
+ return 0;
+}
+
+static int attach_eventfd(struct lguest *lg, const unsigned long __user *input)
+{
+ unsigned long addr, fd;
+ int err;
+
+ if (get_user(addr, input) != 0)
+ return -EFAULT;
+ input++;
+ if (get_user(fd, input) != 0)
+ return -EFAULT;
+
+ mutex_lock(&lguest_lock);
+ err = add_eventfd(lg, addr, fd);
+ mutex_unlock(&lguest_lock);
+
+ return 0;
}
/*L:050 Sending an interrupt is done by writing LHREQ_IRQ and an interrupt
@@ -45,9 +96,8 @@ static int user_send_irq(struct lg_cpu *cpu, const unsigned long __user *input)
return -EFAULT;
if (irq >= LGUEST_IRQS)
return -EINVAL;
- /* Next time the Guest runs, the core code will see if it can deliver
- * this interrupt. */
- set_bit(irq, cpu->irqs_pending);
+
+ set_interrupt(cpu, irq);
return 0;
}
@@ -126,9 +176,6 @@ static int lg_cpu_start(struct lg_cpu *cpu, unsigned id, unsigned long start_ip)
* address. */
lguest_arch_setup_regs(cpu, start_ip);
- /* Initialize the queue for the Waker to wait on */
- init_waitqueue_head(&cpu->break_wq);
-
/* We keep a pointer to the Launcher task (ie. current task) for when
* other Guests want to wake this one (eg. console input). */
cpu->tsk = current;
@@ -185,6 +232,13 @@ static int initialize(struct file *file, const unsigned long __user *input)
goto unlock;
}
+ lg->eventfds = kmalloc(sizeof(*lg->eventfds), GFP_KERNEL);
+ if (!lg->eventfds) {
+ err = -ENOMEM;
+ goto free_lg;
+ }
+ lg->eventfds->num = 0;
+
/* Populate the easy fields of our "struct lguest" */
lg->mem_base = (void __user *)args[0];
lg->pfn_limit = args[1];
@@ -192,7 +246,7 @@ static int initialize(struct file *file, const unsigned long __user *input)
/* This is the first cpu (cpu 0) and it will start booting at args[2] */
err = lg_cpu_start(&lg->cpus[0], 0, args[2]);
if (err)
- goto release_guest;
+ goto free_eventfds;
/* Initialize the Guest's shadow page tables, using the toplevel
* address the Launcher gave us. This allocates memory, so can fail. */
@@ -211,7 +265,9 @@ static int initialize(struct file *file, const unsigned long __user *input)
free_regs:
/* FIXME: This should be in free_vcpu */
free_page(lg->cpus[0].regs_page);
-release_guest:
+free_eventfds:
+ kfree(lg->eventfds);
+free_lg:
kfree(lg);
unlock:
mutex_unlock(&lguest_lock);
@@ -252,11 +308,6 @@ static ssize_t write(struct file *file, const char __user *in,
/* Once the Guest is dead, you can only read() why it died. */
if (lg->dead)
return -ENOENT;
-
- /* If you're not the task which owns the Guest, all you can do
- * is break the Launcher out of running the Guest. */
- if (current != cpu->tsk && req != LHREQ_BREAK)
- return -EPERM;
}
switch (req) {
@@ -264,8 +315,8 @@ static ssize_t write(struct file *file, const char __user *in,
return initialize(file, input);
case LHREQ_IRQ:
return user_send_irq(cpu, input);
- case LHREQ_BREAK:
- return break_guest_out(cpu, input);
+ case LHREQ_EVENTFD:
+ return attach_eventfd(lg, input);
default:
return -EINVAL;
}
@@ -303,6 +354,12 @@ static int close(struct inode *inode, struct file *file)
* the Launcher's memory management structure. */
mmput(lg->cpus[i].mm);
}
+
+ /* Release any eventfds they registered. */
+ for (i = 0; i < lg->eventfds->num; i++)
+ fput(lg->eventfds->map[i].event);
+ kfree(lg->eventfds);
+
/* If lg->dead doesn't contain an error code it will be NULL or a
* kmalloc()ed string, either of which is ok to hand to kfree(). */
if (!IS_ERR(lg->dead))
diff --git a/drivers/lguest/page_tables.c b/drivers/lguest/page_tables.c
index a059cf9..a6fe1ab 100644
--- a/drivers/lguest/page_tables.c
+++ b/drivers/lguest/page_tables.c
@@ -53,6 +53,17 @@
* page. */
#define SWITCHER_PGD_INDEX (PTRS_PER_PGD - 1)
+/* For PAE we need the PMD index as well. We use the last 2MB, so we
+ * will need the last pmd entry of the last pmd page. */
+#ifdef CONFIG_X86_PAE
+#define SWITCHER_PMD_INDEX (PTRS_PER_PMD - 1)
+#define RESERVE_MEM 2U
+#define CHECK_GPGD_MASK _PAGE_PRESENT
+#else
+#define RESERVE_MEM 4U
+#define CHECK_GPGD_MASK _PAGE_TABLE
+#endif
+
/* We actually need a separate PTE page for each CPU. Remember that after the
* Switcher code itself comes two pages for each CPU, and we don't want this
* CPU's guest to see the pages of any other CPU. */
@@ -73,24 +84,59 @@ static pgd_t *spgd_addr(struct lg_cpu *cpu, u32 i, unsigned long vaddr)
{
unsigned int index = pgd_index(vaddr);
+#ifndef CONFIG_X86_PAE
/* We kill any Guest trying to touch the Switcher addresses. */
if (index >= SWITCHER_PGD_INDEX) {
kill_guest(cpu, "attempt to access switcher pages");
index = 0;
}
+#endif
/* Return a pointer index'th pgd entry for the i'th page table. */
return &cpu->lg->pgdirs[i].pgdir[index];
}
+#ifdef CONFIG_X86_PAE
+/* This routine then takes the PGD entry given above, which contains the
+ * address of the PMD page. It then returns a pointer to the PMD entry for the
+ * given address. */
+static pmd_t *spmd_addr(struct lg_cpu *cpu, pgd_t spgd, unsigned long vaddr)
+{
+ unsigned int index = pmd_index(vaddr);
+ pmd_t *page;
+
+ /* We kill any Guest trying to touch the Switcher addresses. */
+ if (pgd_index(vaddr) == SWITCHER_PGD_INDEX &&
+ index >= SWITCHER_PMD_INDEX) {
+ kill_guest(cpu, "attempt to access switcher pages");
+ index = 0;
+ }
+
+ /* You should never call this if the PGD entry wasn't valid */
+ BUG_ON(!(pgd_flags(spgd) & _PAGE_PRESENT));
+ page = __va(pgd_pfn(spgd) << PAGE_SHIFT);
+
+ return &page[index];
+}
+#endif
+
/* This routine then takes the page directory entry returned above, which
* contains the address of the page table entry (PTE) page. It then returns a
* pointer to the PTE entry for the given address. */
-static pte_t *spte_addr(pgd_t spgd, unsigned long vaddr)
+static pte_t *spte_addr(struct lg_cpu *cpu, pgd_t spgd, unsigned long vaddr)
{
+#ifdef CONFIG_X86_PAE
+ pmd_t *pmd = spmd_addr(cpu, spgd, vaddr);
+ pte_t *page = __va(pmd_pfn(*pmd) << PAGE_SHIFT);
+
+ /* You should never call this if the PMD entry wasn't valid */
+ BUG_ON(!(pmd_flags(*pmd) & _PAGE_PRESENT));
+#else
pte_t *page = __va(pgd_pfn(spgd) << PAGE_SHIFT);
/* You should never call this if the PGD entry wasn't valid */
BUG_ON(!(pgd_flags(spgd) & _PAGE_PRESENT));
- return &page[(vaddr >> PAGE_SHIFT) % PTRS_PER_PTE];
+#endif
+
+ return &page[pte_index(vaddr)];
}
/* These two functions just like the above two, except they access the Guest
@@ -101,12 +147,32 @@ static unsigned long gpgd_addr(struct lg_cpu *cpu, unsigned long vaddr)
return cpu->lg->pgdirs[cpu->cpu_pgd].gpgdir + index * sizeof(pgd_t);
}
-static unsigned long gpte_addr(pgd_t gpgd, unsigned long vaddr)
+#ifdef CONFIG_X86_PAE
+static unsigned long gpmd_addr(pgd_t gpgd, unsigned long vaddr)
+{
+ unsigned long gpage = pgd_pfn(gpgd) << PAGE_SHIFT;
+ BUG_ON(!(pgd_flags(gpgd) & _PAGE_PRESENT));
+ return gpage + pmd_index(vaddr) * sizeof(pmd_t);
+}
+
+static unsigned long gpte_addr(struct lg_cpu *cpu,
+ pmd_t gpmd, unsigned long vaddr)
+{
+ unsigned long gpage = pmd_pfn(gpmd) << PAGE_SHIFT;
+
+ BUG_ON(!(pmd_flags(gpmd) & _PAGE_PRESENT));
+ return gpage + pte_index(vaddr) * sizeof(pte_t);
+}
+#else
+static unsigned long gpte_addr(struct lg_cpu *cpu,
+ pgd_t gpgd, unsigned long vaddr)
{
unsigned long gpage = pgd_pfn(gpgd) << PAGE_SHIFT;
+
BUG_ON(!(pgd_flags(gpgd) & _PAGE_PRESENT));
- return gpage + ((vaddr>>PAGE_SHIFT) % PTRS_PER_PTE) * sizeof(pte_t);
+ return gpage + pte_index(vaddr) * sizeof(pte_t);
}
+#endif
/*:*/
/*M:014 get_pfn is slow: we could probably try to grab batches of pages here as
@@ -171,7 +237,7 @@ static void release_pte(pte_t pte)
/* Remember that get_user_pages_fast() took a reference to the page, in
* get_pfn()? We have to put it back now. */
if (pte_flags(pte) & _PAGE_PRESENT)
- put_page(pfn_to_page(pte_pfn(pte)));
+ put_page(pte_page(pte));
}
/*:*/
@@ -184,11 +250,20 @@ static void check_gpte(struct lg_cpu *cpu, pte_t gpte)
static void check_gpgd(struct lg_cpu *cpu, pgd_t gpgd)
{
- if ((pgd_flags(gpgd) & ~_PAGE_TABLE) ||
+ if ((pgd_flags(gpgd) & ~CHECK_GPGD_MASK) ||
(pgd_pfn(gpgd) >= cpu->lg->pfn_limit))
kill_guest(cpu, "bad page directory entry");
}
+#ifdef CONFIG_X86_PAE
+static void check_gpmd(struct lg_cpu *cpu, pmd_t gpmd)
+{
+ if ((pmd_flags(gpmd) & ~_PAGE_TABLE) ||
+ (pmd_pfn(gpmd) >= cpu->lg->pfn_limit))
+ kill_guest(cpu, "bad page middle directory entry");
+}
+#endif
+
/*H:330
* (i) Looking up a page table entry when the Guest faults.
*
@@ -207,6 +282,11 @@ bool demand_page(struct lg_cpu *cpu, unsigned long vaddr, int errcode)
pte_t gpte;
pte_t *spte;
+#ifdef CONFIG_X86_PAE
+ pmd_t *spmd;
+ pmd_t gpmd;
+#endif
+
/* First step: get the top-level Guest page table entry. */
gpgd = lgread(cpu, gpgd_addr(cpu, vaddr), pgd_t);
/* Toplevel not present? We can't map it in. */
@@ -228,12 +308,45 @@ bool demand_page(struct lg_cpu *cpu, unsigned long vaddr, int errcode)
check_gpgd(cpu, gpgd);
/* And we copy the flags to the shadow PGD entry. The page
* number in the shadow PGD is the page we just allocated. */
- *spgd = __pgd(__pa(ptepage) | pgd_flags(gpgd));
+ set_pgd(spgd, __pgd(__pa(ptepage) | pgd_flags(gpgd)));
}
+#ifdef CONFIG_X86_PAE
+ gpmd = lgread(cpu, gpmd_addr(gpgd, vaddr), pmd_t);
+ /* middle level not present? We can't map it in. */
+ if (!(pmd_flags(gpmd) & _PAGE_PRESENT))
+ return false;
+
+ /* Now look at the matching shadow entry. */
+ spmd = spmd_addr(cpu, *spgd, vaddr);
+
+ if (!(pmd_flags(*spmd) & _PAGE_PRESENT)) {
+ /* No shadow entry: allocate a new shadow PTE page. */
+ unsigned long ptepage = get_zeroed_page(GFP_KERNEL);
+
+ /* This is not really the Guest's fault, but killing it is
+ * simple for this corner case. */
+ if (!ptepage) {
+ kill_guest(cpu, "out of memory allocating pte page");
+ return false;
+ }
+
+ /* We check that the Guest pmd is OK. */
+ check_gpmd(cpu, gpmd);
+
+ /* And we copy the flags to the shadow PMD entry. The page
+ * number in the shadow PMD is the page we just allocated. */
+ native_set_pmd(spmd, __pmd(__pa(ptepage) | pmd_flags(gpmd)));
+ }
+
+ /* OK, now we look at the lower level in the Guest page table: keep its
+ * address, because we might update it later. */
+ gpte_ptr = gpte_addr(cpu, gpmd, vaddr);
+#else
/* OK, now we look at the lower level in the Guest page table: keep its
* address, because we might update it later. */
- gpte_ptr = gpte_addr(gpgd, vaddr);
+ gpte_ptr = gpte_addr(cpu, gpgd, vaddr);
+#endif
gpte = lgread(cpu, gpte_ptr, pte_t);
/* If this page isn't in the Guest page tables, we can't page it in. */
@@ -259,7 +372,7 @@ bool demand_page(struct lg_cpu *cpu, unsigned long vaddr, int errcode)
gpte = pte_mkdirty(gpte);
/* Get the pointer to the shadow PTE entry we're going to set. */
- spte = spte_addr(*spgd, vaddr);
+ spte = spte_addr(cpu, *spgd, vaddr);
/* If there was a valid shadow PTE entry here before, we release it.
* This can happen with a write to a previously read-only entry. */
release_pte(*spte);
@@ -273,7 +386,7 @@ bool demand_page(struct lg_cpu *cpu, unsigned long vaddr, int errcode)
* table entry, even if the Guest says it's writable. That way
* we will come back here when a write does actually occur, so
* we can update the Guest's _PAGE_DIRTY flag. */
- *spte = gpte_to_spte(cpu, pte_wrprotect(gpte), 0);
+ native_set_pte(spte, gpte_to_spte(cpu, pte_wrprotect(gpte), 0));
/* Finally, we write the Guest PTE entry back: we've set the
* _PAGE_ACCESSED and maybe the _PAGE_DIRTY flags. */
@@ -301,14 +414,23 @@ static bool page_writable(struct lg_cpu *cpu, unsigned long vaddr)
pgd_t *spgd;
unsigned long flags;
+#ifdef CONFIG_X86_PAE
+ pmd_t *spmd;
+#endif
/* Look at the current top level entry: is it present? */
spgd = spgd_addr(cpu, cpu->cpu_pgd, vaddr);
if (!(pgd_flags(*spgd) & _PAGE_PRESENT))
return false;
+#ifdef CONFIG_X86_PAE
+ spmd = spmd_addr(cpu, *spgd, vaddr);
+ if (!(pmd_flags(*spmd) & _PAGE_PRESENT))
+ return false;
+#endif
+
/* Check the flags on the pte entry itself: it must be present and
* writable. */
- flags = pte_flags(*(spte_addr(*spgd, vaddr)));
+ flags = pte_flags(*(spte_addr(cpu, *spgd, vaddr)));
return (flags & (_PAGE_PRESENT|_PAGE_RW)) == (_PAGE_PRESENT|_PAGE_RW);
}
@@ -322,8 +444,43 @@ void pin_page(struct lg_cpu *cpu, unsigned long vaddr)
kill_guest(cpu, "bad stack page %#lx", vaddr);
}
+#ifdef CONFIG_X86_PAE
+static void release_pmd(pmd_t *spmd)
+{
+ /* If the entry's not present, there's nothing to release. */
+ if (pmd_flags(*spmd) & _PAGE_PRESENT) {
+ unsigned int i;
+ pte_t *ptepage = __va(pmd_pfn(*spmd) << PAGE_SHIFT);
+ /* For each entry in the page, we might need to release it. */
+ for (i = 0; i < PTRS_PER_PTE; i++)
+ release_pte(ptepage[i]);
+ /* Now we can free the page of PTEs */
+ free_page((long)ptepage);
+ /* And zero out the PMD entry so we never release it twice. */
+ native_set_pmd(spmd, __pmd(0));
+ }
+}
+
+static void release_pgd(pgd_t *spgd)
+{
+ /* If the entry's not present, there's nothing to release. */
+ if (pgd_flags(*spgd) & _PAGE_PRESENT) {
+ unsigned int i;
+ pmd_t *pmdpage = __va(pgd_pfn(*spgd) << PAGE_SHIFT);
+
+ for (i = 0; i < PTRS_PER_PMD; i++)
+ release_pmd(&pmdpage[i]);
+
+ /* Now we can free the page of PMDs */
+ free_page((long)pmdpage);
+ /* And zero out the PGD entry so we never release it twice. */
+ set_pgd(spgd, __pgd(0));
+ }
+}
+
+#else /* !CONFIG_X86_PAE */
/*H:450 If we chase down the release_pgd() code, it looks like this: */
-static void release_pgd(struct lguest *lg, pgd_t *spgd)
+static void release_pgd(pgd_t *spgd)
{
/* If the entry's not present, there's nothing to release. */
if (pgd_flags(*spgd) & _PAGE_PRESENT) {
@@ -341,7 +498,7 @@ static void release_pgd(struct lguest *lg, pgd_t *spgd)
*spgd = __pgd(0);
}
}
-
+#endif
/*H:445 We saw flush_user_mappings() twice: once from the flush_user_mappings()
* hypercall and once in new_pgdir() when we re-used a top-level pgdir page.
* It simply releases every PTE page from 0 up to the Guest's kernel address. */
@@ -350,7 +507,7 @@ static void flush_user_mappings(struct lguest *lg, int idx)
unsigned int i;
/* Release every pgd entry up to the kernel's address. */
for (i = 0; i < pgd_index(lg->kernel_address); i++)
- release_pgd(lg, lg->pgdirs[idx].pgdir + i);
+ release_pgd(lg->pgdirs[idx].pgdir + i);
}
/*H:440 (v) Flushing (throwing away) page tables,
@@ -369,7 +526,9 @@ unsigned long guest_pa(struct lg_cpu *cpu, unsigned long vaddr)
{
pgd_t gpgd;
pte_t gpte;
-
+#ifdef CONFIG_X86_PAE
+ pmd_t gpmd;
+#endif
/* First step: get the top-level Guest page table entry. */
gpgd = lgread(cpu, gpgd_addr(cpu, vaddr), pgd_t);
/* Toplevel not present? We can't map it in. */
@@ -378,7 +537,14 @@ unsigned long guest_pa(struct lg_cpu *cpu, unsigned long vaddr)
return -1UL;
}
- gpte = lgread(cpu, gpte_addr(gpgd, vaddr), pte_t);
+#ifdef CONFIG_X86_PAE
+ gpmd = lgread(cpu, gpmd_addr(gpgd, vaddr), pmd_t);
+ if (!(pmd_flags(gpmd) & _PAGE_PRESENT))
+ kill_guest(cpu, "Bad address %#lx", vaddr);
+ gpte = lgread(cpu, gpte_addr(cpu, gpmd, vaddr), pte_t);
+#else
+ gpte = lgread(cpu, gpte_addr(cpu, gpgd, vaddr), pte_t);
+#endif
if (!(pte_flags(gpte) & _PAGE_PRESENT))
kill_guest(cpu, "Bad address %#lx", vaddr);
@@ -405,6 +571,9 @@ static unsigned int new_pgdir(struct lg_cpu *cpu,
int *blank_pgdir)
{
unsigned int next;
+#ifdef CONFIG_X86_PAE
+ pmd_t *pmd_table;
+#endif
/* We pick one entry at random to throw out. Choosing the Least
* Recently Used might be better, but this is easy. */
@@ -416,10 +585,27 @@ static unsigned int new_pgdir(struct lg_cpu *cpu,
/* If the allocation fails, just keep using the one we have */
if (!cpu->lg->pgdirs[next].pgdir)
next = cpu->cpu_pgd;
- else
- /* This is a blank page, so there are no kernel
- * mappings: caller must map the stack! */
+ else {
+#ifdef CONFIG_X86_PAE
+ /* In PAE mode, allocate a pmd page and populate the
+ * last pgd entry. */
+ pmd_table = (pmd_t *)get_zeroed_page(GFP_KERNEL);
+ if (!pmd_table) {
+ free_page((long)cpu->lg->pgdirs[next].pgdir);
+ set_pgd(cpu->lg->pgdirs[next].pgdir, __pgd(0));
+ next = cpu->cpu_pgd;
+ } else {
+ set_pgd(cpu->lg->pgdirs[next].pgdir +
+ SWITCHER_PGD_INDEX,
+ __pgd(__pa(pmd_table) | _PAGE_PRESENT));
+ /* This is a blank page, so there are no kernel
+ * mappings: caller must map the stack! */
+ *blank_pgdir = 1;
+ }
+#else
*blank_pgdir = 1;
+#endif
+ }
}
/* Record which Guest toplevel this shadows. */
cpu->lg->pgdirs[next].gpgdir = gpgdir;
@@ -431,7 +617,7 @@ static unsigned int new_pgdir(struct lg_cpu *cpu,
/*H:430 (iv) Switching page tables
*
- * Now we've seen all the page table setting and manipulation, let's see what
+ * Now we've seen all the page table setting and manipulation, let's see
* 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 lg_cpu *cpu, unsigned long pgtable)
@@ -460,10 +646,25 @@ static void release_all_pagetables(struct lguest *lg)
/* Every shadow pagetable this Guest has */
for (i = 0; i < ARRAY_SIZE(lg->pgdirs); i++)
- if (lg->pgdirs[i].pgdir)
+ if (lg->pgdirs[i].pgdir) {
+#ifdef CONFIG_X86_PAE
+ pgd_t *spgd;
+ pmd_t *pmdpage;
+ unsigned int k;
+
+ /* Get the last pmd page. */
+ spgd = lg->pgdirs[i].pgdir + SWITCHER_PGD_INDEX;
+ pmdpage = __va(pgd_pfn(*spgd) << PAGE_SHIFT);
+
+ /* And release the pmd entries of that pmd page,
+ * except for the switcher pmd. */
+ for (k = 0; k < SWITCHER_PMD_INDEX; k++)
+ release_pmd(&pmdpage[k]);
+#endif
/* Every PGD entry except the Switcher at the top */
for (j = 0; j < SWITCHER_PGD_INDEX; j++)
- release_pgd(lg, lg->pgdirs[i].pgdir + j);
+ release_pgd(lg->pgdirs[i].pgdir + j);
+ }
}
/* We also throw away everything when a Guest tells us it's changed a kernel
@@ -504,24 +705,37 @@ static void do_set_pte(struct lg_cpu *cpu, int idx,
{
/* Look up the matching shadow page directory entry. */
pgd_t *spgd = spgd_addr(cpu, idx, vaddr);
+#ifdef CONFIG_X86_PAE
+ pmd_t *spmd;
+#endif
/* If the top level isn't present, there's no entry to update. */
if (pgd_flags(*spgd) & _PAGE_PRESENT) {
- /* Otherwise, we start by releasing the existing entry. */
- pte_t *spte = spte_addr(*spgd, vaddr);
- release_pte(*spte);
-
- /* If they're setting this entry as dirty or accessed, we might
- * as well put that entry they've given us in now. This shaves
- * 10% off a copy-on-write micro-benchmark. */
- if (pte_flags(gpte) & (_PAGE_DIRTY | _PAGE_ACCESSED)) {
- check_gpte(cpu, gpte);
- *spte = gpte_to_spte(cpu, gpte,
- pte_flags(gpte) & _PAGE_DIRTY);
- } else
- /* Otherwise kill it and we can demand_page() it in
- * later. */
- *spte = __pte(0);
+#ifdef CONFIG_X86_PAE
+ spmd = spmd_addr(cpu, *spgd, vaddr);
+ if (pmd_flags(*spmd) & _PAGE_PRESENT) {
+#endif
+ /* Otherwise, we start by releasing
+ * the existing entry. */
+ pte_t *spte = spte_addr(cpu, *spgd, vaddr);
+ release_pte(*spte);
+
+ /* If they're setting this entry as dirty or accessed,
+ * we might as well put that entry they've given us
+ * in now. This shaves 10% off a
+ * copy-on-write micro-benchmark. */
+ if (pte_flags(gpte) & (_PAGE_DIRTY | _PAGE_ACCESSED)) {
+ check_gpte(cpu, gpte);
+ native_set_pte(spte,
+ gpte_to_spte(cpu, gpte,
+ pte_flags(gpte) & _PAGE_DIRTY));
+ } else
+ /* Otherwise kill it and we can demand_page()
+ * it in later. */
+ native_set_pte(spte, __pte(0));
+#ifdef CONFIG_X86_PAE
+ }
+#endif
}
}
@@ -568,12 +782,10 @@ void guest_set_pte(struct lg_cpu *cpu,
*
* So with that in mind here's our code to to update a (top-level) PGD entry:
*/
-void guest_set_pmd(struct lguest *lg, unsigned long gpgdir, u32 idx)
+void guest_set_pgd(struct lguest *lg, unsigned long gpgdir, u32 idx)
{
int pgdir;
- /* The kernel seems to try to initialize this early on: we ignore its
- * attempts to map over the Switcher. */
if (idx >= SWITCHER_PGD_INDEX)
return;
@@ -581,8 +793,14 @@ void guest_set_pmd(struct lguest *lg, unsigned long gpgdir, u32 idx)
pgdir = find_pgdir(lg, gpgdir);
if (pgdir < ARRAY_SIZE(lg->pgdirs))
/* ... throw it away. */
- release_pgd(lg, lg->pgdirs[pgdir].pgdir + idx);
+ release_pgd(lg->pgdirs[pgdir].pgdir + idx);
}
+#ifdef CONFIG_X86_PAE
+void guest_set_pmd(struct lguest *lg, unsigned long pmdp, u32 idx)
+{
+ guest_pagetable_clear_all(&lg->cpus[0]);
+}
+#endif
/* Once we know how much memory we have we can construct simple identity
* (which set virtual == physical) and linear mappings
@@ -596,8 +814,16 @@ static unsigned long setup_pagetables(struct lguest *lg,
{
pgd_t __user *pgdir;
pte_t __user *linear;
- unsigned int mapped_pages, i, linear_pages, phys_linear;
unsigned long mem_base = (unsigned long)lg->mem_base;
+ unsigned int mapped_pages, i, linear_pages;
+#ifdef CONFIG_X86_PAE
+ pmd_t __user *pmds;
+ unsigned int j;
+ pgd_t pgd;
+ pmd_t pmd;
+#else
+ unsigned int phys_linear;
+#endif
/* We have mapped_pages frames to map, so we need
* linear_pages page tables to map them. */
@@ -610,6 +836,9 @@ static unsigned long setup_pagetables(struct lguest *lg,
/* Now we use the next linear_pages pages as pte pages */
linear = (void *)pgdir - linear_pages * PAGE_SIZE;
+#ifdef CONFIG_X86_PAE
+ pmds = (void *)linear - PAGE_SIZE;
+#endif
/* Linear mapping is easy: put every page's address into the
* mapping in order. */
for (i = 0; i < mapped_pages; i++) {
@@ -621,6 +850,22 @@ static unsigned long setup_pagetables(struct lguest *lg,
/* The top level points to the linear page table pages above.
* We setup the identity and linear mappings here. */
+#ifdef CONFIG_X86_PAE
+ for (i = j = 0; i < mapped_pages && j < PTRS_PER_PMD;
+ i += PTRS_PER_PTE, j++) {
+ native_set_pmd(&pmd, __pmd(((unsigned long)(linear + i)
+ - mem_base) | _PAGE_PRESENT | _PAGE_RW | _PAGE_USER));
+
+ if (copy_to_user(&pmds[j], &pmd, sizeof(pmd)) != 0)
+ return -EFAULT;
+ }
+
+ set_pgd(&pgd, __pgd(((u32)pmds - mem_base) | _PAGE_PRESENT));
+ if (copy_to_user(&pgdir[0], &pgd, sizeof(pgd)) != 0)
+ return -EFAULT;
+ if (copy_to_user(&pgdir[3], &pgd, sizeof(pgd)) != 0)
+ return -EFAULT;
+#else
phys_linear = (unsigned long)linear - mem_base;
for (i = 0; i < mapped_pages; i += PTRS_PER_PTE) {
pgd_t pgd;
@@ -633,6 +878,7 @@ static unsigned long setup_pagetables(struct lguest *lg,
&pgd, sizeof(pgd)))
return -EFAULT;
}
+#endif
/* We return the top level (guest-physical) address: remember where
* this is. */
@@ -648,7 +894,10 @@ int init_guest_pagetable(struct lguest *lg)
u64 mem;
u32 initrd_size;
struct boot_params __user *boot = (struct boot_params *)lg->mem_base;
-
+#ifdef CONFIG_X86_PAE
+ pgd_t *pgd;
+ pmd_t *pmd_table;
+#endif
/* Get the Guest memory size and the ramdisk size from the boot header
* located at lg->mem_base (Guest address 0). */
if (copy_from_user(&mem, &boot->e820_map[0].size, sizeof(mem))
@@ -663,6 +912,15 @@ int init_guest_pagetable(struct lguest *lg)
lg->pgdirs[0].pgdir = (pgd_t *)get_zeroed_page(GFP_KERNEL);
if (!lg->pgdirs[0].pgdir)
return -ENOMEM;
+#ifdef CONFIG_X86_PAE
+ pgd = lg->pgdirs[0].pgdir;
+ pmd_table = (pmd_t *) get_zeroed_page(GFP_KERNEL);
+ if (!pmd_table)
+ return -ENOMEM;
+
+ set_pgd(pgd + SWITCHER_PGD_INDEX,
+ __pgd(__pa(pmd_table) | _PAGE_PRESENT));
+#endif
lg->cpus[0].cpu_pgd = 0;
return 0;
}
@@ -672,17 +930,24 @@ void page_table_guest_data_init(struct lg_cpu *cpu)
{
/* We get the kernel address: above this is all kernel memory. */
if (get_user(cpu->lg->kernel_address,
- &cpu->lg->lguest_data->kernel_address)
- /* We tell the Guest that it can't use the top 4MB of virtual
- * addresses used by the Switcher. */
- || put_user(4U*1024*1024, &cpu->lg->lguest_data->reserve_mem)
- || put_user(cpu->lg->pgdirs[0].gpgdir, &cpu->lg->lguest_data->pgdir))
+ &cpu->lg->lguest_data->kernel_address)
+ /* We tell the Guest that it can't use the top 2 or 4 MB
+ * of virtual addresses used by the Switcher. */
+ || put_user(RESERVE_MEM * 1024 * 1024,
+ &cpu->lg->lguest_data->reserve_mem)
+ || put_user(cpu->lg->pgdirs[0].gpgdir,
+ &cpu->lg->lguest_data->pgdir))
kill_guest(cpu, "bad guest page %p", cpu->lg->lguest_data);
/* In flush_user_mappings() we loop from 0 to
* "pgd_index(lg->kernel_address)". This assumes it won't hit the
* Switcher mappings, so check that now. */
+#ifdef CONFIG_X86_PAE
+ if (pgd_index(cpu->lg->kernel_address) == SWITCHER_PGD_INDEX &&
+ pmd_index(cpu->lg->kernel_address) == SWITCHER_PMD_INDEX)
+#else
if (pgd_index(cpu->lg->kernel_address) >= SWITCHER_PGD_INDEX)
+#endif
kill_guest(cpu, "bad kernel address %#lx",
cpu->lg->kernel_address);
}
@@ -708,16 +973,30 @@ void free_guest_pagetable(struct lguest *lg)
void map_switcher_in_guest(struct lg_cpu *cpu, struct lguest_pages *pages)
{
pte_t *switcher_pte_page = __get_cpu_var(switcher_pte_pages);
- pgd_t switcher_pgd;
pte_t regs_pte;
unsigned long pfn;
+#ifdef CONFIG_X86_PAE
+ pmd_t switcher_pmd;
+ pmd_t *pmd_table;
+
+ native_set_pmd(&switcher_pmd, pfn_pmd(__pa(switcher_pte_page) >>
+ PAGE_SHIFT, PAGE_KERNEL_EXEC));
+
+ pmd_table = __va(pgd_pfn(cpu->lg->
+ pgdirs[cpu->cpu_pgd].pgdir[SWITCHER_PGD_INDEX])
+ << PAGE_SHIFT);
+ native_set_pmd(&pmd_table[SWITCHER_PMD_INDEX], switcher_pmd);
+#else
+ pgd_t switcher_pgd;
+
/* Make the last PGD entry for this Guest point to the Switcher's PTE
* page for this CPU (with appropriate flags). */
- switcher_pgd = __pgd(__pa(switcher_pte_page) | __PAGE_KERNEL);
+ switcher_pgd = __pgd(__pa(switcher_pte_page) | __PAGE_KERNEL_EXEC);
cpu->lg->pgdirs[cpu->cpu_pgd].pgdir[SWITCHER_PGD_INDEX] = switcher_pgd;
+#endif
/* We also change the Switcher PTE page. When we're running the Guest,
* we want the Guest's "regs" page to appear where the first Switcher
* page for this CPU is. This is an optimization: when the Switcher
@@ -726,8 +1005,9 @@ void map_switcher_in_guest(struct lg_cpu *cpu, struct lguest_pages *pages)
* page is already mapped there, we don't have to copy them out
* again. */
pfn = __pa(cpu->regs_page) >> PAGE_SHIFT;
- regs_pte = pfn_pte(pfn, __pgprot(__PAGE_KERNEL));
- switcher_pte_page[(unsigned long)pages/PAGE_SIZE%PTRS_PER_PTE] = regs_pte;
+ native_set_pte(&regs_pte, pfn_pte(pfn, PAGE_KERNEL));
+ native_set_pte(&switcher_pte_page[pte_index((unsigned long)pages)],
+ regs_pte);
}
/*:*/
@@ -752,21 +1032,21 @@ static __init void populate_switcher_pte_page(unsigned int cpu,
/* The first entries are easy: they map the Switcher code. */
for (i = 0; i < pages; i++) {
- pte[i] = mk_pte(switcher_page[i],
- __pgprot(_PAGE_PRESENT|_PAGE_ACCESSED));
+ native_set_pte(&pte[i], mk_pte(switcher_page[i],
+ __pgprot(_PAGE_PRESENT|_PAGE_ACCESSED)));
}
/* The only other thing we map is this CPU's pair of pages. */
i = pages + cpu*2;
/* First page (Guest registers) is writable from the Guest */
- pte[i] = pfn_pte(page_to_pfn(switcher_page[i]),
- __pgprot(_PAGE_PRESENT|_PAGE_ACCESSED|_PAGE_RW));
+ native_set_pte(&pte[i], pfn_pte(page_to_pfn(switcher_page[i]),
+ __pgprot(_PAGE_PRESENT|_PAGE_ACCESSED|_PAGE_RW)));
/* The second page contains the "struct lguest_ro_state", and is
* read-only. */
- pte[i+1] = pfn_pte(page_to_pfn(switcher_page[i+1]),
- __pgprot(_PAGE_PRESENT|_PAGE_ACCESSED));
+ native_set_pte(&pte[i+1], pfn_pte(page_to_pfn(switcher_page[i+1]),
+ __pgprot(_PAGE_PRESENT|_PAGE_ACCESSED)));
}
/* We've made it through the page table code. Perhaps our tired brains are
diff --git a/drivers/lguest/segments.c b/drivers/lguest/segments.c
index 7ede64f..482ed5a 100644
--- a/drivers/lguest/segments.c
+++ b/drivers/lguest/segments.c
@@ -150,7 +150,7 @@ void load_guest_gdt_entry(struct lg_cpu *cpu, u32 num, u32 lo, u32 hi)
{
/* We assume the Guest has the same number of GDT entries as the
* Host, otherwise we'd have to dynamically allocate the Guest GDT. */
- if (num > ARRAY_SIZE(cpu->arch.gdt))
+ if (num >= ARRAY_SIZE(cpu->arch.gdt))
kill_guest(cpu, "too many gdt entries %i", num);
/* Set it up, then fix it. */