Initial import

1 files changed, 258 insertions, 0 deletions

diff --git a/drivers/lguest/lg.h b/drivers/lguest/lg.h
new file mode 100644
index 000000000..ac8ad0461
--- /dev/null
+++ b/drivers/lguest/lg.h
@@ -0,0 +1,258 @@
+#ifndef _LGUEST_H
+#define _LGUEST_H
+
+#ifndef __ASSEMBLY__
+#include <linux/types.h>
+#include <linux/init.h>
+#include <linux/stringify.h>
+#include <linux/lguest.h>
+#include <linux/lguest_launcher.h>
+#include <linux/wait.h>
+#include <linux/hrtimer.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+
+#include <asm/lguest.h>
+
+struct pgdir {
+	unsigned long gpgdir;
+	bool switcher_mapped;
+	int last_host_cpu;
+	pgd_t *pgdir;
+};
+
+/* We have two pages shared with guests, per cpu.  */
+struct lguest_pages {
+	/* This is the stack page mapped rw in guest */
+	char spare[PAGE_SIZE - sizeof(struct lguest_regs)];
+	struct lguest_regs regs;
+
+	/* This is the host state & guest descriptor page, ro in guest */
+	struct lguest_ro_state state;
+} __attribute__((aligned(PAGE_SIZE)));
+
+#define CHANGED_IDT		1
+#define CHANGED_GDT		2
+#define CHANGED_GDT_TLS		4 /* Actually a subset of CHANGED_GDT */
+#define CHANGED_ALL	        3
+
+struct lg_cpu {
+	unsigned int id;
+	struct lguest *lg;
+	struct task_struct *tsk;
+	struct mm_struct *mm; 	/* == tsk->mm, but that becomes NULL on exit */
+
+	u32 cr2;
+	int ts;
+	u32 esp1;
+	u16 ss1;
+
+	/* Bitmap of what has changed: see CHANGED_* above. */
+	int changed;
+
+	/* Pending operation. */
+	struct lguest_pending pending;
+
+	unsigned long *reg_read; /* register from LHREQ_GETREG */
+
+	/* At end of a page shared mapped over lguest_pages in guest. */
+	unsigned long regs_page;
+	struct lguest_regs *regs;
+
+	struct lguest_pages *last_pages;
+
+	/* Initialization mode: linear map everything. */
+	bool linear_pages;
+	int cpu_pgd; /* Which pgd this cpu is currently using */
+
+	/* If a hypercall was asked for, this points to the arguments. */
+	struct hcall_args *hcall;
+	u32 next_hcall;
+
+	/* Virtual clock device */
+	struct hrtimer hrt;
+
+	/* Did the Guest tell us to halt? */
+	int halted;
+
+	/* Pending virtual interrupts */
+	DECLARE_BITMAP(irqs_pending, LGUEST_IRQS);
+
+	struct lg_cpu_arch arch;
+};
+
+/* The private info the thread maintains about the guest. */
+struct lguest {
+	struct lguest_data __user *lguest_data;
+	struct lg_cpu cpus[NR_CPUS];
+	unsigned int nr_cpus;
+
+	/* Valid guest memory pages must be < this. */
+	u32 pfn_limit;
+
+	/* Device memory is >= pfn_limit and < device_limit. */
+	u32 device_limit;
+
+	/*
+	 * This provides the offset to the base of guest-physical memory in the
+	 * Launcher.
+	 */
+	void __user *mem_base;
+	unsigned long kernel_address;
+
+	struct pgdir pgdirs[4];
+
+	unsigned long noirq_iret;
+
+	unsigned int stack_pages;
+	u32 tsc_khz;
+
+	/* Dead? */
+	const char *dead;
+};
+
+extern struct mutex lguest_lock;
+
+/* core.c: */
+bool lguest_address_ok(const struct lguest *lg,
+		       unsigned long addr, unsigned long len);
+void __lgread(struct lg_cpu *, void *, unsigned long, unsigned);
+void __lgwrite(struct lg_cpu *, unsigned long, const void *, unsigned);
+extern struct page **lg_switcher_pages;
+
+/*H:035
+ * Using memory-copy operations like that is usually inconvient, so we
+ * have the following helper macros which read and write a specific type (often
+ * an unsigned long).
+ *
+ * This reads into a variable of the given type then returns that.
+ */
+#define lgread(cpu, addr, type)						\
+	({ type _v; __lgread((cpu), &_v, (addr), sizeof(_v)); _v; })
+
+/* This checks that the variable is of the given type, then writes it out. */
+#define lgwrite(cpu, addr, type, val)				\
+	do {							\
+		typecheck(type, val);				\
+		__lgwrite((cpu), (addr), &(val), sizeof(val));	\
+	} while(0)
+/* (end of memory access helper routines) :*/
+
+int run_guest(struct lg_cpu *cpu, unsigned long __user *user);
+
+/*
+ * Helper macros to obtain the first 12 or the last 20 bits, this is only the
+ * first step in the migration to the kernel types.  pte_pfn is already defined
+ * 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: */
+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);
+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,
+		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);
+void free_interrupts(void);
+
+/* segments.c: */
+void setup_default_gdt_entries(struct lguest_ro_state *state);
+void setup_guest_gdt(struct lg_cpu *cpu);
+void load_guest_gdt_entry(struct lg_cpu *cpu, unsigned int i,
+			  u32 low, u32 hi);
+void guest_load_tls(struct lg_cpu *cpu, unsigned long tls_array);
+void copy_gdt(const struct lg_cpu *cpu, struct desc_struct *gdt);
+void copy_gdt_tls(const struct lg_cpu *cpu, struct desc_struct *gdt);
+
+/* page_tables.c: */
+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,
+		   unsigned long vaddr, pte_t val);
+void map_switcher_in_guest(struct lg_cpu *cpu, struct lguest_pages *pages);
+bool demand_page(struct lg_cpu *cpu, unsigned long cr2, int errcode,
+		 unsigned long *iomem);
+void pin_page(struct lg_cpu *cpu, unsigned long vaddr);
+bool __guest_pa(struct lg_cpu *cpu, unsigned long vaddr, unsigned long *paddr);
+unsigned long guest_pa(struct lg_cpu *cpu, unsigned long vaddr);
+void page_table_guest_data_init(struct lg_cpu *cpu);
+
+/* <arch>/core.c: */
+void lguest_arch_host_init(void);
+void lguest_arch_host_fini(void);
+void lguest_arch_run_guest(struct lg_cpu *cpu);
+void lguest_arch_handle_trap(struct lg_cpu *cpu);
+int lguest_arch_init_hypercalls(struct lg_cpu *cpu);
+int lguest_arch_do_hcall(struct lg_cpu *cpu, struct hcall_args *args);
+void lguest_arch_setup_regs(struct lg_cpu *cpu, unsigned long start);
+unsigned long *lguest_arch_regptr(struct lg_cpu *cpu, size_t reg_off, bool any);
+
+/* <arch>/switcher.S: */
+extern char start_switcher_text[], end_switcher_text[], switch_to_guest[];
+
+/* lguest_user.c: */
+int lguest_device_init(void);
+void lguest_device_remove(void);
+
+/* hypercalls.c: */
+void do_hypercalls(struct lg_cpu *cpu);
+void write_timestamp(struct lg_cpu *cpu);
+
+/*L:035
+ * Let's step aside for the moment, to study one important routine that's used
+ * widely in the Host code.
+ *
+ * There are many cases where the Guest can do something invalid, like pass crap
+ * to a hypercall.  Since only the Guest kernel can make hypercalls, it's quite
+ * acceptable to simply terminate the Guest and give the Launcher a nicely
+ * formatted reason.  It's also simpler for the Guest itself, which doesn't
+ * need to check most hypercalls for "success"; if you're still running, it
+ * succeeded.
+ *
+ * Once this is called, the Guest will never run again, so most Host code can
+ * call this then continue as if nothing had happened.  This means many
+ * functions don't have to explicitly return an error code, which keeps the
+ * code simple.
+ *
+ * It also means that this can be called more than once: only the first one is
+ * remembered.  The only trick is that we still need to kill the Guest even if
+ * we can't allocate memory to store the reason.  Linux has a neat way of
+ * packing error codes into invalid pointers, so we use that here.
+ *
+ * Like any macro which uses an "if", it is safely wrapped in a run-once "do {
+ * } while(0)".
+ */
+#define kill_guest(cpu, fmt...)					\
+do {								\
+	if (!(cpu)->lg->dead) {					\
+		(cpu)->lg->dead = kasprintf(GFP_ATOMIC, fmt);	\
+		if (!(cpu)->lg->dead)				\
+			(cpu)->lg->dead = ERR_PTR(-ENOMEM);	\
+	}							\
+} while(0)
+/* (End of aside) :*/
+
+#endif	/* __ASSEMBLY__ */
+#endif	/* _LGUEST_H */