Merge git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-lguest-and-virtio (db6f2040) · Commits · e / devices / android_kernel_teracube_2e

Documentation/lguest/lguest.c

+7 −0

Original line number	Diff line number	Diff line
		@@ -1630,6 +1630,13 @@ static bool service_io(struct device *dev)
		}
		}

		/* OK, so we noted that it was pretty poor to use an fdatasync as a
		* barrier. But Christoph Hellwig points out that we need a sync
		* afterwards as well: "Barriers specify no reordering to the front
		* or the back." And Jens Axboe confirmed it, so here we are: */
		if (out->type & VIRTIO_BLK_T_BARRIER)
		fdatasync(vblk->fd);

		/* We can't trigger an IRQ, because we're not the Launcher. It does
		* that when we tell it we're done. */
		add_used(dev->vq, head, wlen);

arch/x86/include/asm/lguest_hcall.h

+4 −20

Original line number	Diff line number	Diff line
		@@ -26,36 +26,20 @@

		#ifndef __ASSEMBLY__
		#include <asm/hw_irq.h>
		#include <asm/kvm_para.h>

		/*G:031 But first, how does our Guest contact the Host to ask for privileged
		* operations? There are two ways: the direct way is to make a "hypercall",
		* to make requests of the Host Itself.
		*
		* Our hypercall mechanism uses the highest unused trap code (traps 32 and
		* above are used by real hardware interrupts). Fifteen hypercalls are
		* We use the KVM hypercall mechanism. Eighteen hypercalls are
		* available: the hypercall number is put in the %eax register, and the
		* arguments (when required) are placed in %edx, %ebx and %ecx. If a return
		* arguments (when required) are placed in %ebx, %ecx and %edx. If a return
		* value makes sense, it's returned in %eax.
		*
		* Grossly invalid calls result in Sudden Death at the hands of the vengeful
		* Host, rather than returning failure. This reflects Winston Churchill's
		* definition of a gentleman: "someone who is only rude intentionally". */
		static inline unsigned long
		hcall(unsigned long call,
		unsigned long arg1, unsigned long arg2, unsigned long arg3)
		{
		/* "int" is the Intel instruction to trigger a trap. */
		asm volatile("int $" __stringify(LGUEST_TRAP_ENTRY)
		/* The call in %eax (aka "a") might be overwritten */
		: "=a"(call)
		/* The arguments are in %eax, %edx, %ebx & %ecx */
		: "a"(call), "d"(arg1), "b"(arg2), "c"(arg3)
		/* "memory" means this might write somewhere in memory.
		* This isn't true for all calls, but it's safe to tell
		* gcc that it might happen so it doesn't get clever. */
		: "memory");
		return call;
		}
		/:/

		/* Can't use our min() macro here: needs to be a constant */
		@@ -64,7 +48,7 @@ hcall(unsigned long call,
		#define LHCALL_RING_SIZE 64
		struct hcall_args {
		/* These map directly onto eax, ebx, ecx, edx in struct lguest_regs */
		unsigned long arg0, arg2, arg3, arg1;
		unsigned long arg0, arg1, arg2, arg3;
		};

		#endif /* !__ASSEMBLY__ */

arch/x86/lguest/boot.c

+57 −29

Original line number	Diff line number	Diff line
		@@ -107,7 +107,7 @@ static void async_hcall(unsigned long call, unsigned long arg1,
		local_irq_save(flags);
		if (lguest_data.hcall_status[next_call] != 0xFF) {
		/* Table full, so do normal hcall which will flush table. */
		hcall(call, arg1, arg2, arg3);
		kvm_hypercall3(call, arg1, arg2, arg3);
		} else {
		lguest_data.hcalls[next_call].arg0 = call;
		lguest_data.hcalls[next_call].arg1 = arg1;
		@@ -134,13 +134,32 @@ static void async_hcall(unsigned long call, unsigned long arg1,
		*
		* So, when we're in lazy mode, we call async_hcall() to store the call for
		* future processing: */
		static void lazy_hcall(unsigned long call,
		static void lazy_hcall1(unsigned long call,
		unsigned long arg1)
		{
		if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_NONE)
		kvm_hypercall1(call, arg1);
		else
		async_hcall(call, arg1, 0, 0);
		}

		static void lazy_hcall2(unsigned long call,
		unsigned long arg1,
		unsigned long arg2)
		{
		if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_NONE)
		kvm_hypercall2(call, arg1, arg2);
		else
		async_hcall(call, arg1, arg2, 0);
		}

		static void lazy_hcall3(unsigned long call,
		unsigned long arg1,
		unsigned long arg2,
		unsigned long arg3)
		{
		if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_NONE)
		hcall(call, arg1, arg2, arg3);
		kvm_hypercall3(call, arg1, arg2, arg3);
		else
		async_hcall(call, arg1, arg2, arg3);
		}
		@@ -150,7 +169,7 @@ static void lazy_hcall(unsigned long call,
		static void lguest_leave_lazy_mode(void)
		{
		paravirt_leave_lazy(paravirt_get_lazy_mode());
		hcall(LHCALL_FLUSH_ASYNC, 0, 0, 0);
		kvm_hypercall0(LHCALL_FLUSH_ASYNC);
		}

		/*G:033
		@@ -229,7 +248,7 @@ static void lguest_write_idt_entry(gate_desc *dt,
		/* Keep the local copy up to date. */
		native_write_idt_entry(dt, entrynum, g);
		/* Tell Host about this new entry. */
		hcall(LHCALL_LOAD_IDT_ENTRY, entrynum, desc[0], desc[1]);
		kvm_hypercall3(LHCALL_LOAD_IDT_ENTRY, entrynum, desc[0], desc[1]);
		}

		/* Changing to a different IDT is very rare: we keep the IDT up-to-date every
		@@ -241,7 +260,7 @@ static void lguest_load_idt(const struct desc_ptr *desc)
		struct desc_struct idt = (void )desc->address;

		for (i = 0; i < (desc->size+1)/8; i++)
		hcall(LHCALL_LOAD_IDT_ENTRY, i, idt[i].a, idt[i].b);
		kvm_hypercall3(LHCALL_LOAD_IDT_ENTRY, i, idt[i].a, idt[i].b);
		}

		/*
		@@ -262,7 +281,7 @@ static void lguest_load_idt(const struct desc_ptr *desc)
		static void lguest_load_gdt(const struct desc_ptr *desc)
		{
		BUG_ON((desc->size + 1) / 8 != GDT_ENTRIES);
		hcall(LHCALL_LOAD_GDT, __pa(desc->address), GDT_ENTRIES, 0);
		kvm_hypercall2(LHCALL_LOAD_GDT, __pa(desc->address), GDT_ENTRIES);
		}

		/* For a single GDT entry which changes, we do the lazy thing: alter our GDT,
		@@ -272,7 +291,7 @@ static void lguest_write_gdt_entry(struct desc_struct *dt, int entrynum,
		const void *desc, int type)
		{
		native_write_gdt_entry(dt, entrynum, desc, type);
		hcall(LHCALL_LOAD_GDT, __pa(dt), GDT_ENTRIES, 0);
		kvm_hypercall2(LHCALL_LOAD_GDT, __pa(dt), GDT_ENTRIES);
		}

		/* OK, I lied. There are three "thread local storage" GDT entries which change
		@@ -284,7 +303,7 @@ static void lguest_load_tls(struct thread_struct *t, unsigned int cpu)
		* can't handle us removing entries we're currently using. So we clear
		* the GS register here: if it's needed it'll be reloaded anyway. */
		lazy_load_gs(0);
		lazy_hcall(LHCALL_LOAD_TLS, __pa(&t->tls_array), cpu, 0);
		lazy_hcall2(LHCALL_LOAD_TLS, __pa(&t->tls_array), cpu);
		}

		/*G:038 That's enough excitement for now, back to ploughing through each of
		@@ -382,7 +401,7 @@ static void lguest_cpuid(unsigned int ax, unsigned int bx,
		static unsigned long current_cr0;
		static void lguest_write_cr0(unsigned long val)
		{
		lazy_hcall(LHCALL_TS, val & X86_CR0_TS, 0, 0);
		lazy_hcall1(LHCALL_TS, val & X86_CR0_TS);
		current_cr0 = val;
		}

		@@ -396,7 +415,7 @@ static unsigned long lguest_read_cr0(void)
		* the vowels have been optimized out. */
		static void lguest_clts(void)
		{
		lazy_hcall(LHCALL_TS, 0, 0, 0);
		lazy_hcall1(LHCALL_TS, 0);
		current_cr0 &= ~X86_CR0_TS;
		}

		@@ -418,7 +437,7 @@ static bool cr3_changed = false;
		static void lguest_write_cr3(unsigned long cr3)
		{
		lguest_data.pgdir = cr3;
		lazy_hcall(LHCALL_NEW_PGTABLE, cr3, 0, 0);
		lazy_hcall1(LHCALL_NEW_PGTABLE, cr3);
		cr3_changed = true;
		}

		@@ -490,11 +509,17 @@ static void lguest_write_cr4(unsigned long val)
		* into a process' address space. We set the entry then tell the Host the
		* toplevel and address this corresponds to. The Guest uses one pagetable per
		* process, so we need to tell the Host which one we're changing (mm->pgd). */
		static void lguest_pte_update(struct mm_struct *mm, unsigned long addr,
		pte_t *ptep)
		{
		lazy_hcall3(LHCALL_SET_PTE, __pa(mm->pgd), addr, ptep->pte_low);
		}

		static void lguest_set_pte_at(struct mm_struct *mm, unsigned long addr,
		pte_t *ptep, pte_t pteval)
		{
		*ptep = pteval;
		lazy_hcall(LHCALL_SET_PTE, __pa(mm->pgd), addr, pteval.pte_low);
		lguest_pte_update(mm, addr, ptep);
		}

		/* The Guest calls this to set a top-level entry. Again, we set the entry then
		@@ -503,8 +528,8 @@ static void lguest_set_pte_at(struct mm_struct *mm, unsigned long addr,
		static void lguest_set_pmd(pmd_t *pmdp, pmd_t pmdval)
		{
		*pmdp = pmdval;
		lazy_hcall(LHCALL_SET_PMD, __pa(pmdp)&PAGE_MASK,
		(__pa(pmdp)&(PAGE_SIZE-1))/4, 0);
		lazy_hcall2(LHCALL_SET_PMD, __pa(pmdp) & PAGE_MASK,
		(__pa(pmdp) & (PAGE_SIZE - 1)) / 4);
		}

		/* There are a couple of legacy places where the kernel sets a PTE, but we
		@@ -520,7 +545,7 @@ static void lguest_set_pte(pte_t *ptep, pte_t pteval)
		{
		*ptep = pteval;
		if (cr3_changed)
		lazy_hcall(LHCALL_FLUSH_TLB, 1, 0, 0);
		lazy_hcall1(LHCALL_FLUSH_TLB, 1);
		}

		/* Unfortunately for Lguest, the pv_mmu_ops for page tables were based on
		@@ -536,7 +561,7 @@ static void lguest_set_pte(pte_t *ptep, pte_t pteval)
		static void lguest_flush_tlb_single(unsigned long addr)
		{
		/* Simply set it to zero: if it was not, it will fault back in. */
		lazy_hcall(LHCALL_SET_PTE, lguest_data.pgdir, addr, 0);
		lazy_hcall3(LHCALL_SET_PTE, lguest_data.pgdir, addr, 0);
		}

		/* This is what happens after the Guest has removed a large number of entries.
		@@ -544,7 +569,7 @@ static void lguest_flush_tlb_single(unsigned long addr)
		* have changed, ie. virtual addresses below PAGE_OFFSET. */
		static void lguest_flush_tlb_user(void)
		{
		lazy_hcall(LHCALL_FLUSH_TLB, 0, 0, 0);
		lazy_hcall1(LHCALL_FLUSH_TLB, 0);
		}

		/* This is called when the kernel page tables have changed. That's not very
		@@ -552,7 +577,7 @@ static void lguest_flush_tlb_user(void)
		* slow), so it's worth separating this from the user flushing above. */
		static void lguest_flush_tlb_kernel(void)
		{
		lazy_hcall(LHCALL_FLUSH_TLB, 1, 0, 0);
		lazy_hcall1(LHCALL_FLUSH_TLB, 1);
		}

		/*
		@@ -689,7 +714,7 @@ static int lguest_clockevent_set_next_event(unsigned long delta,
		}

		/* Please wake us this far in the future. */
		hcall(LHCALL_SET_CLOCKEVENT, delta, 0, 0);
		kvm_hypercall1(LHCALL_SET_CLOCKEVENT, delta);
		return 0;
		}

		@@ -700,7 +725,7 @@ static void lguest_clockevent_set_mode(enum clock_event_mode 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);
		kvm_hypercall0(LHCALL_SET_CLOCKEVENT);
		break;
		case CLOCK_EVT_MODE_ONESHOT:
		/* This is what we expect. */
		@@ -775,7 +800,7 @@ static void lguest_time_init(void)
		static void lguest_load_sp0(struct tss_struct *tss,
		struct thread_struct *thread)
		{
		lazy_hcall(LHCALL_SET_STACK, __KERNEL_DS\|0x1, thread->sp0,
		lazy_hcall3(LHCALL_SET_STACK, __KERNEL_DS \| 0x1, thread->sp0,
		THREAD_SIZE / PAGE_SIZE);
		}

		@@ -849,7 +874,7 @@ static void set_lguest_basic_apic_ops(void)
		/* STOP! Until an interrupt comes in. */
		static void lguest_safe_halt(void)
		{
		hcall(LHCALL_HALT, 0, 0, 0);
		kvm_hypercall0(LHCALL_HALT);
		}

		/* The SHUTDOWN hypercall takes a string to describe what's happening, and
		@@ -859,7 +884,8 @@ static void lguest_safe_halt(void)
		* rather than virtual addresses, so we use __pa() here. */
		static void lguest_power_off(void)
		{
		hcall(LHCALL_SHUTDOWN, __pa("Power down"), LGUEST_SHUTDOWN_POWEROFF, 0);
		kvm_hypercall2(LHCALL_SHUTDOWN, __pa("Power down"),
		LGUEST_SHUTDOWN_POWEROFF);
		}

		/*
		@@ -869,7 +895,7 @@ static void lguest_power_off(void)
		*/
		static int lguest_panic(struct notifier_block nb, unsigned long l, void p)
		{
		hcall(LHCALL_SHUTDOWN, __pa(p), LGUEST_SHUTDOWN_POWEROFF, 0);
		kvm_hypercall2(LHCALL_SHUTDOWN, __pa(p), LGUEST_SHUTDOWN_POWEROFF);
		/* The hcall won't return, but to keep gcc happy, we're "done". */
		return NOTIFY_DONE;
		}
		@@ -910,7 +936,7 @@ static __init int early_put_chars(u32 vtermno, const char *buf, int count)
		len = sizeof(scratch) - 1;
		scratch[len] = '\0';
		memcpy(scratch, buf, len);
		hcall(LHCALL_NOTIFY, __pa(scratch), 0, 0);
		kvm_hypercall1(LHCALL_NOTIFY, __pa(scratch));

		/* This routine returns the number of bytes actually written. */
		return len;
		@@ -920,7 +946,7 @@ static __init int early_put_chars(u32 vtermno, const char *buf, int count)
		* Launcher to reboot us. */
		static void lguest_restart(char *reason)
		{
		hcall(LHCALL_SHUTDOWN, __pa(reason), LGUEST_SHUTDOWN_RESTART, 0);
		kvm_hypercall2(LHCALL_SHUTDOWN, __pa(reason), LGUEST_SHUTDOWN_RESTART);
		}

		/*G:050
		@@ -1040,6 +1066,8 @@ __init void lguest_init(void)
		pv_mmu_ops.read_cr3 = lguest_read_cr3;
		pv_mmu_ops.lazy_mode.enter = paravirt_enter_lazy_mmu;
		pv_mmu_ops.lazy_mode.leave = lguest_leave_lazy_mode;
		pv_mmu_ops.pte_update = lguest_pte_update;
		pv_mmu_ops.pte_update_defer = lguest_pte_update;

		#ifdef CONFIG_X86_LOCAL_APIC
		/* apic read/write intercepts */

arch/x86/lguest/i386_head.S

+2 −2

Original line number	Diff line number	Diff line
		@@ -27,8 +27,8 @@ ENTRY(lguest_entry)
		/* We make the "initialization" hypercall now to tell the Host about
		* us, and also find out where it put our page tables. */
		movl $LHCALL_LGUEST_INIT, %eax
		movl $lguest_data - __PAGE_OFFSET, %edx
		int $LGUEST_TRAP_ENTRY
		movl $lguest_data - __PAGE_OFFSET, %ebx
		.byte 0x0f,0x01,0xc1 /* KVM_HYPERCALL */

		/* Set up the initial stack so we can run C code. */
		movl $(init_thread_union+THREAD_SIZE),%esp

drivers/lguest/core.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -152,7 +152,7 @@ static void unmap_switcher(void)
		* code. We have to check that the range is below the pfn_limit the Launcher
		* gave us. We have to make sure that addr + len doesn't give us a false
		* positive by overflowing, too. */
		int lguest_address_ok(const struct lguest *lg,
		bool lguest_address_ok(const struct lguest *lg,
		unsigned long addr, unsigned long len)
		{
		return (addr+len) / PAGE_SIZE < lg->pfn_limit && (addr+len >= addr);