lguest: the host code
This is the code for the "lg.ko" module, which allows lguest guests to
be launched.
[akpm@linux-foundation.org: update for futex-new-private-futexes]
[akpm@linux-foundation.org: build fix]
[jmorris@namei.org: lguest: use hrtimers]
[akpm@linux-foundation.org: x86_64 build fix]
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Andi Kleen <ak@suse.de>
Cc: Eric Dumazet <dada1@cosmosbay.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/lguest/lguest.c b/drivers/lguest/lguest.c
index b3a72bd..b9a58b7 100644
--- a/drivers/lguest/lguest.c
+++ b/drivers/lguest/lguest.c
@@ -25,6 +25,8 @@
#include <linux/screen_info.h>
#include <linux/irq.h>
#include <linux/interrupt.h>
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
#include <linux/lguest.h>
#include <linux/lguest_launcher.h>
#include <linux/lguest_bus.h>
@@ -37,6 +39,7 @@
#include <asm/e820.h>
#include <asm/mce.h>
#include <asm/io.h>
+//#include <asm/sched-clock.h>
/* Declarations for definitions in lguest_guest.S */
extern char lguest_noirq_start[], lguest_noirq_end[];
@@ -54,7 +57,6 @@
.blocked_interrupts = { 1 }, /* Block timer interrupts */
};
struct lguest_device_desc *lguest_devices;
-static __initdata const struct lguest_boot_info *boot = __va(0);
static enum paravirt_lazy_mode lazy_mode;
static void lguest_lazy_mode(enum paravirt_lazy_mode mode)
@@ -210,7 +212,7 @@
case 1: /* Basic feature request. */
/* We only allow kernel to see SSE3, CMPXCHG16B and SSSE3 */
*ecx &= 0x00002201;
- /* Similarly: SSE, SSE2, FXSR, MMX, CMOV, CMPXCHG8B, FPU. */
+ /* SSE, SSE2, FXSR, MMX, CMOV, CMPXCHG8B, FPU. */
*edx &= 0x07808101;
/* Host wants to know when we flush kernel pages: set PGE. */
*edx |= 0x00002000;
@@ -346,24 +348,104 @@
return hcall(LHCALL_GET_WALLCLOCK, 0, 0, 0);
}
-static void lguest_time_irq(unsigned int irq, struct irq_desc *desc)
+static cycle_t lguest_clock_read(void)
{
- do_timer(hcall(LHCALL_TIMER_READ, 0, 0, 0));
- update_process_times(user_mode_vm(get_irq_regs()));
+ if (lguest_data.tsc_khz)
+ return native_read_tsc();
+ else
+ return jiffies;
}
-static u64 sched_clock_base;
+/* This is what we tell the kernel is our clocksource. */
+static struct clocksource lguest_clock = {
+ .name = "lguest",
+ .rating = 400,
+ .read = lguest_clock_read,
+};
+
+/* We also need a "struct clock_event_device": Linux asks us to set it to go
+ * off some time in the future. Actually, James Morris figured all this out, I
+ * just applied the patch. */
+static int lguest_clockevent_set_next_event(unsigned long delta,
+ struct clock_event_device *evt)
+{
+ if (delta < LG_CLOCK_MIN_DELTA) {
+ if (printk_ratelimit())
+ printk(KERN_DEBUG "%s: small delta %lu ns\n",
+ __FUNCTION__, delta);
+ return -ETIME;
+ }
+ hcall(LHCALL_SET_CLOCKEVENT, delta, 0, 0);
+ return 0;
+}
+
+static void lguest_clockevent_set_mode(enum clock_event_mode mode,
+ struct clock_event_device *evt)
+{
+ switch (mode) {
+ case CLOCK_EVT_MODE_UNUSED:
+ case CLOCK_EVT_MODE_SHUTDOWN:
+ /* A 0 argument shuts the clock down. */
+ hcall(LHCALL_SET_CLOCKEVENT, 0, 0, 0);
+ break;
+ case CLOCK_EVT_MODE_ONESHOT:
+ /* This is what we expect. */
+ break;
+ case CLOCK_EVT_MODE_PERIODIC:
+ BUG();
+ }
+}
+
+/* This describes our primitive timer chip. */
+static struct clock_event_device lguest_clockevent = {
+ .name = "lguest",
+ .features = CLOCK_EVT_FEAT_ONESHOT,
+ .set_next_event = lguest_clockevent_set_next_event,
+ .set_mode = lguest_clockevent_set_mode,
+ .rating = INT_MAX,
+ .mult = 1,
+ .shift = 0,
+ .min_delta_ns = LG_CLOCK_MIN_DELTA,
+ .max_delta_ns = LG_CLOCK_MAX_DELTA,
+};
+
+/* This is the Guest timer interrupt handler (hardware interrupt 0). We just
+ * call the clockevent infrastructure and it does whatever needs doing. */
+static void lguest_time_irq(unsigned int irq, struct irq_desc *desc)
+{
+ unsigned long flags;
+
+ /* Don't interrupt us while this is running. */
+ local_irq_save(flags);
+ lguest_clockevent.event_handler(&lguest_clockevent);
+ local_irq_restore(flags);
+}
+
static void lguest_time_init(void)
{
set_irq_handler(0, lguest_time_irq);
- hcall(LHCALL_TIMER_READ, 0, 0, 0);
- sched_clock_base = jiffies_64;
- enable_lguest_irq(0);
-}
-static unsigned long long lguest_sched_clock(void)
-{
- return (jiffies_64 - sched_clock_base) * (1000000000 / HZ);
+ /* We use the TSC if the Host tells us we can, otherwise a dumb
+ * jiffies-based clock. */
+ if (lguest_data.tsc_khz) {
+ lguest_clock.shift = 22;
+ lguest_clock.mult = clocksource_khz2mult(lguest_data.tsc_khz,
+ lguest_clock.shift);
+ lguest_clock.mask = CLOCKSOURCE_MASK(64);
+ lguest_clock.flags = CLOCK_SOURCE_IS_CONTINUOUS;
+ } else {
+ /* To understand this, start at kernel/time/jiffies.c... */
+ lguest_clock.shift = 8;
+ lguest_clock.mult = (((u64)NSEC_PER_SEC<<8)/ACTHZ) << 8;
+ lguest_clock.mask = CLOCKSOURCE_MASK(32);
+ }
+ clocksource_register(&lguest_clock);
+
+ /* We can't set cpumask in the initializer: damn C limitations! */
+ lguest_clockevent.cpumask = cpumask_of_cpu(0);
+ clockevents_register_device(&lguest_clockevent);
+
+ enable_lguest_irq(0);
}
static void lguest_load_esp0(struct tss_struct *tss,
@@ -418,8 +500,7 @@
/* We do this here because lockcheck barfs if before start_kernel */
atomic_notifier_chain_register(&panic_notifier_list, &paniced);
- e820.nr_map = 0;
- add_memory_region(0, PFN_PHYS(boot->max_pfn), E820_RAM);
+ add_memory_region(E820_MAP->addr, E820_MAP->size, E820_MAP->type);
return "LGUEST";
}
@@ -450,8 +531,13 @@
return insn_len;
}
-__init void lguest_init(void)
+__init void lguest_init(void *boot)
{
+ /* Copy boot parameters first. */
+ memcpy(&boot_params, boot, PARAM_SIZE);
+ memcpy(boot_command_line, __va(boot_params.hdr.cmd_line_ptr),
+ COMMAND_LINE_SIZE);
+
paravirt_ops.name = "lguest";
paravirt_ops.paravirt_enabled = 1;
paravirt_ops.kernel_rpl = 1;
@@ -498,10 +584,8 @@
paravirt_ops.time_init = lguest_time_init;
paravirt_ops.set_lazy_mode = lguest_lazy_mode;
paravirt_ops.wbinvd = lguest_wbinvd;
- paravirt_ops.sched_clock = lguest_sched_clock;
hcall(LHCALL_LGUEST_INIT, __pa(&lguest_data), 0, 0);
- strncpy(boot_command_line, boot->cmdline, COMMAND_LINE_SIZE);
/* We use top of mem for initial pagetables. */
init_pg_tables_end = __pa(pg0);
@@ -532,13 +616,6 @@
add_preferred_console("hvc", 0, NULL);
- if (boot->initrd_size) {
- /* We stash this at top of memory. */
- INITRD_START = boot->max_pfn*PAGE_SIZE - boot->initrd_size;
- INITRD_SIZE = boot->initrd_size;
- LOADER_TYPE = 0xFF;
- }
-
pm_power_off = lguest_power_off;
start_kernel();
}