예제 #1
0
/* This is called just after a mm has been created, but it has not
   been used yet.  We need to make sure that its pagetable is all
   read-only, and can be pinned. */
void xen_pgd_pin(pgd_t *pgd)
{
	struct multicall_space mcs;
	struct mmuext_op *op;

	xen_mc_batch();

	if (pgd_walk(pgd, pin_page, TASK_SIZE)) {
		/* re-enable interrupts for kmap_flush_unused */
		xen_mc_issue(0);
		kmap_flush_unused();
		xen_mc_batch();
	}

	mcs = __xen_mc_entry(sizeof(*op));
	op = mcs.args;

#ifdef CONFIG_X86_PAE
	op->cmd = MMUEXT_PIN_L3_TABLE;
#else
	op->cmd = MMUEXT_PIN_L2_TABLE;
#endif
	op->arg1.mfn = pfn_to_mfn(PFN_DOWN(__pa(pgd)));
	MULTI_mmuext_op(mcs.mc, op, 1, NULL, DOMID_SELF);

	xen_mc_issue(0);
}
예제 #2
0
/*
 * Set the page permissions for a particular virtual address.  If the
 * address is a vmalloc mapping (or other non-linear mapping), then
 * find the linear mapping of the page and also set its protections to
 * match.
 */
static void set_aliased_prot(void *v, pgprot_t prot)
{
	int level;
	pte_t *ptep;
	pte_t pte;
	unsigned long pfn;
	struct page *page;

	ptep = lookup_address((unsigned long)v, &level);
	BUG_ON(ptep == NULL);

	pfn = pte_pfn(*ptep);
	page = pfn_to_page(pfn);

	pte = pfn_pte(pfn, prot);

	if (HYPERVISOR_update_va_mapping((unsigned long)v, pte, 0))
		BUG();

	if (!PageHighMem(page)) {
		void *av = __va(PFN_PHYS(pfn));

		if (av != v)
			if (HYPERVISOR_update_va_mapping((unsigned long)av, pte, 0))
				BUG();
	} else
		kmap_flush_unused();
}
예제 #3
0
/*
 * Set the page permissions for a particular virtual address.  If the
 * address is a vmalloc mapping (or other non-linear mapping), then
 * find the linear mapping of the page and also set its protections to
 * match.
 */
static void set_aliased_prot(void *v, pgprot_t prot)
{
	int level;
	pte_t *ptep;
	pte_t pte;
	unsigned long pfn;
	struct page *page;
	unsigned char dummy;

	ptep = lookup_address((unsigned long)v, &level);
	BUG_ON(ptep == NULL);

	pfn = pte_pfn(*ptep);
	page = pfn_to_page(pfn);

	pte = pfn_pte(pfn, prot);

	/*
	 * Careful: update_va_mapping() will fail if the virtual address
	 * we're poking isn't populated in the page tables.  We don't
	 * need to worry about the direct map (that's always in the page
	 * tables), but we need to be careful about vmap space.  In
	 * particular, the top level page table can lazily propagate
	 * entries between processes, so if we've switched mms since we
	 * vmapped the target in the first place, we might not have the
	 * top-level page table entry populated.
	 *
	 * We disable preemption because we want the same mm active when
	 * we probe the target and when we issue the hypercall.  We'll
	 * have the same nominal mm, but if we're a kernel thread, lazy
	 * mm dropping could change our pgd.
	 *
	 * Out of an abundance of caution, this uses __get_user() to fault
	 * in the target address just in case there's some obscure case
	 * in which the target address isn't readable.
	 */

	preempt_disable();

	pagefault_disable();	/* Avoid warnings due to being atomic. */
	__get_user(dummy, (unsigned char __user __force *)v);
	pagefault_enable();

	if (HYPERVISOR_update_va_mapping((unsigned long)v, pte, 0))
		BUG();

	if (!PageHighMem(page)) {
		void *av = __va(PFN_PHYS(pfn));

		if (av != v)
			if (HYPERVISOR_update_va_mapping((unsigned long)av, pte, 0))
				BUG();
	} else
		kmap_flush_unused();

	preempt_enable();
}
예제 #4
0
int ion_cp_change_chunks_state(unsigned long chunks, unsigned int nchunks,
				unsigned int chunk_size,
				enum cp_mem_usage usage,
				int lock)
{
	struct cp2_lock2_req request;
	u32 resp;

	request.mem_usage = usage;
	request.lock = lock;
	request.flags = 0;

	request.chunks.chunk_list = (unsigned int *)chunks;
	request.chunks.chunk_list_size = nchunks;
	request.chunks.chunk_size = chunk_size;

	kmap_flush_unused();
	kmap_atomic_flush_unused();
	return scm_call(SCM_SVC_MP, MEM_PROTECT_LOCK_ID2,
			&request, sizeof(request), &resp, sizeof(resp));

}
예제 #5
0
void make_page_readonly(void *va, unsigned int feature)
{
	pte_t *pte;
	int rc;

	if (xen_feature(feature))
		return;

	pte = virt_to_ptep(va);
	rc = HYPERVISOR_update_va_mapping(
		(unsigned long)va, pte_wrprotect(*pte), 0);
	if (rc) /* fallback? */
		xen_l1_entry_update(pte, pte_wrprotect(*pte));
	if ((unsigned long)va >= (unsigned long)high_memory) {
		unsigned long pfn = pte_pfn(*pte);
#ifdef CONFIG_HIGHMEM
		if (pfn >= highstart_pfn)
			kmap_flush_unused(); /* flush stale writable kmaps */
		else
#endif
			make_lowmem_page_readonly(
				phys_to_virt(pfn << PAGE_SHIFT), feature); 
	}
}
예제 #6
0
static int increase_reservation(unsigned long nr_pages)
{
	unsigned long  pfn, i, flags;
	struct page   *page;
	long           rc;
	struct xen_memory_reservation reservation = {
		.address_bits = 0,
		.extent_order = 0,
		.domid        = DOMID_SELF
	};

	if (nr_pages > ARRAY_SIZE(frame_list))
		nr_pages = ARRAY_SIZE(frame_list);

	balloon_lock(flags);

	page = balloon_first_page();
	for (i = 0; i < nr_pages; i++) {
		BUG_ON(page == NULL);
		frame_list[i] = page_to_pfn(page);;
		page = balloon_next_page(page);
	}

	set_xen_guest_handle(reservation.extent_start, frame_list);
	reservation.nr_extents   = nr_pages;
	rc = HYPERVISOR_memory_op(
		XENMEM_populate_physmap, &reservation);
	if (rc < nr_pages) {
		int ret;
		/* We hit the Xen hard limit: reprobe. */
		set_xen_guest_handle(reservation.extent_start, frame_list);
		reservation.nr_extents   = rc;
		ret = HYPERVISOR_memory_op(XENMEM_decrease_reservation,
				&reservation);
		BUG_ON(ret != rc);
		hard_limit = current_pages + rc - driver_pages;
		goto out;
	}

	for (i = 0; i < nr_pages; i++) {
		page = balloon_retrieve();
		BUG_ON(page == NULL);

		pfn = page_to_pfn(page);
		BUG_ON(!xen_feature(XENFEAT_auto_translated_physmap) &&
		       phys_to_machine_mapping_valid(pfn));

		/* Update P->M and M->P tables. */
		set_phys_to_machine(pfn, frame_list[i]);

#ifdef CONFIG_XEN
		xen_machphys_update(frame_list[i], pfn);

		/* Link back into the page tables if not highmem. */
		if (pfn < max_low_pfn) {
			int ret;
			ret = HYPERVISOR_update_va_mapping(
				(unsigned long)__va(pfn << PAGE_SHIFT),
				pfn_pte_ma(frame_list[i], PAGE_KERNEL),
				0);
			BUG_ON(ret);
		}
#endif
		/* Relinquish the page back to the allocator. */
		ClearPageReserved(page);
		set_page_count(page, 1);
		__free_page(page);
	}

	current_pages += nr_pages;
	totalram_pages = current_pages;

 out:
	balloon_unlock(flags);

	return 0;
}

static int decrease_reservation(unsigned long nr_pages)
{
	unsigned long  pfn, i, flags;
	struct page   *page;
	void          *v;
	int            need_sleep = 0;
	int ret;
	struct xen_memory_reservation reservation = {
		.address_bits = 0,
		.extent_order = 0,
		.domid        = DOMID_SELF
	};

	if (nr_pages > ARRAY_SIZE(frame_list))
		nr_pages = ARRAY_SIZE(frame_list);

	for (i = 0; i < nr_pages; i++) {
		if ((page = alloc_page(GFP_BALLOON)) == NULL) {
			nr_pages = i;
			need_sleep = 1;
			break;
		}

		pfn = page_to_pfn(page);
		frame_list[i] = pfn_to_mfn(pfn);

		if (!PageHighMem(page)) {
			v = phys_to_virt(pfn << PAGE_SHIFT);
			scrub_pages(v, 1);
#ifdef CONFIG_XEN
			ret = HYPERVISOR_update_va_mapping(
				(unsigned long)v, __pte_ma(0), 0);
			BUG_ON(ret);
#endif
		}
#ifdef CONFIG_XEN_SCRUB_PAGES
		else {
			v = kmap(page);
			scrub_pages(v, 1);
			kunmap(page);
		}
#endif
	}

#ifdef CONFIG_XEN
	/* Ensure that ballooned highmem pages don't have kmaps. */
	kmap_flush_unused();
	flush_tlb_all();
#endif

	balloon_lock(flags);

	/* No more mappings: invalidate P2M and add to balloon. */
	for (i = 0; i < nr_pages; i++) {
		pfn = mfn_to_pfn(frame_list[i]);
		set_phys_to_machine(pfn, INVALID_P2M_ENTRY);
		balloon_append(pfn_to_page(pfn));
	}

	set_xen_guest_handle(reservation.extent_start, frame_list);
	reservation.nr_extents   = nr_pages;
	ret = HYPERVISOR_memory_op(XENMEM_decrease_reservation, &reservation);
	BUG_ON(ret != nr_pages);

	current_pages -= nr_pages;
	totalram_pages = current_pages;

	balloon_unlock(flags);

	return need_sleep;
}

/*
 * We avoid multiple worker processes conflicting via the balloon mutex.
 * We may of course race updates of the target counts (which are protected
 * by the balloon lock), or with changes to the Xen hard limit, but we will
 * recover from these in time.
 */
static void balloon_process(void *unused)
{
	int need_sleep = 0;
	long credit;

	down(&balloon_mutex);

	do {
		credit = current_target() - current_pages;
		if (credit > 0)
			need_sleep = (increase_reservation(credit) != 0);
		if (credit < 0)
			need_sleep = (decrease_reservation(-credit) != 0);

#ifndef CONFIG_PREEMPT
		if (need_resched())
			schedule();
#endif
	} while ((credit != 0) && !need_sleep);

	/* Schedule more work if there is some still to be done. */
	if (current_target() != current_pages)
		mod_timer(&balloon_timer, jiffies + HZ);

	up(&balloon_mutex);
}
예제 #7
0
static int increase_reservation(unsigned long nr_pages)
{
	unsigned long  pfn, i, flags;
	struct page   *page;
	long           rc;
	struct xen_memory_reservation reservation = {
		.address_bits = 0,
		.extent_order = 0,
		.domid        = DOMID_SELF
	};

	if (nr_pages > ARRAY_SIZE(frame_list))
		nr_pages = ARRAY_SIZE(frame_list);

	spin_lock_irqsave(&balloon_lock, flags);

	page = balloon_first_page();
	for (i = 0; i < nr_pages; i++) {
		BUG_ON(page == NULL);
		frame_list[i] = page_to_pfn(page);
		page = balloon_next_page(page);
	}

	set_xen_guest_handle(reservation.extent_start, frame_list);
	reservation.nr_extents = nr_pages;
	rc = HYPERVISOR_memory_op(XENMEM_populate_physmap, &reservation);
	if (rc < 0)
		goto out;

	for (i = 0; i < rc; i++) {
		page = balloon_retrieve();
		BUG_ON(page == NULL);

		pfn = page_to_pfn(page);
		BUG_ON(!xen_feature(XENFEAT_auto_translated_physmap) &&
		       phys_to_machine_mapping_valid(pfn));

		set_phys_to_machine(pfn, frame_list[i]);

		/* Link back into the page tables if not highmem. */
#ifdef CONFIG_PVM
		if (!xen_hvm_domain() && pfn < max_low_pfn) {
			int ret;
			ret = HYPERVISOR_update_va_mapping(
				(unsigned long)__va(pfn << PAGE_SHIFT),
				mfn_pte(frame_list[i], PAGE_KERNEL),
				0);
			BUG_ON(ret);
		}
#endif
		/* Relinquish the page back to the allocator. */
		ClearPageReserved(page);
		init_page_count(page);
		__free_page(page);
	}

	balloon_stats.current_pages += rc;
   	if (old_totalram_pages + rc < totalram_pages)
   	{
        printk(KERN_INFO "old_totalram=%luKB, totalram_pages=%luKB\n", old_totalram_pages*4, totalram_pages*4);
       	balloon_stats.current_pages = totalram_pages + totalram_bias;
        printk(KERN_INFO "when ballooning, the mem online! totalram=%luKB, current=%luKB\n", totalram_pages*4, balloon_stats.current_pages*4);
   	}
   	old_totalram_pages = totalram_pages;
	

 out:
	spin_unlock_irqrestore(&balloon_lock, flags);

	return rc < 0 ? rc : rc != nr_pages;
}

static int decrease_reservation(unsigned long nr_pages)
{
	unsigned long  pfn, i, flags;
	struct page   *page;
	int            need_sleep = 0;
	int ret;
	struct xen_memory_reservation reservation = {
		.address_bits = 0,
		.extent_order = 0,
		.domid        = DOMID_SELF
	};

	if (nr_pages > ARRAY_SIZE(frame_list))
		nr_pages = ARRAY_SIZE(frame_list);

	for (i = 0; i < nr_pages; i++) {
		if ((page = alloc_page(GFP_BALLOON)) == NULL) {
			nr_pages = i;
			need_sleep = 1;
			break;
		}

		pfn = page_to_pfn(page);
		frame_list[i] = pfn_to_mfn(pfn);

		scrub_page(page);

		if (!xen_hvm_domain() && !PageHighMem(page)) {
			ret = HYPERVISOR_update_va_mapping(
				(unsigned long)__va(pfn << PAGE_SHIFT),
				__pte_ma(0), 0);
			BUG_ON(ret);
                }

	}

	/* Ensure that ballooned highmem pages don't have kmaps. */
#ifdef CONFIG_PVM
	kmap_flush_unused();
	flush_tlb_all();
#endif
	spin_lock_irqsave(&balloon_lock, flags);

	/* No more mappings: invalidate P2M and add to balloon. */
	for (i = 0; i < nr_pages; i++) {
		pfn = mfn_to_pfn(frame_list[i]);
		set_phys_to_machine(pfn, INVALID_P2M_ENTRY);
		balloon_append(pfn_to_page(pfn));
	}

	set_xen_guest_handle(reservation.extent_start, frame_list);
	reservation.nr_extents   = nr_pages;
	ret = HYPERVISOR_memory_op(XENMEM_decrease_reservation, &reservation);
	BUG_ON(ret != nr_pages);

	balloon_stats.current_pages -= nr_pages;
   	if(old_totalram_pages < totalram_pages + nr_pages)
   	{
        printk(KERN_INFO "old_totalram=%luKB, totalram_pages=%luKB\n", old_totalram_pages*4, totalram_pages*4);
       	balloon_stats.current_pages = totalram_pages + totalram_bias;
        printk(KERN_INFO "when ballooning, the mem online! totalram=%luKB, current=%luKB\n", totalram_pages*4, balloon_stats.current_pages*4);
   	}
   	old_totalram_pages = totalram_pages;
	
	spin_unlock_irqrestore(&balloon_lock, flags);

	return need_sleep;
}

/*
 * We avoid multiple worker processes conflicting via the balloon mutex.
 * We may of course race updates of the target counts (which are protected
 * by the balloon lock), or with changes to the Xen hard limit, but we will
 * recover from these in time.
 */
static void balloon_process(struct work_struct *work)
{
	int need_sleep = 0;
	long credit;
    long total_increase = 0;
	char buffer[16];

	mutex_lock(&balloon_mutex);
    printk(KERN_INFO "totalram_pages=%luKB, current_pages=%luKB,totalram_bias=%luKB\n", totalram_pages*4, balloon_stats.current_pages*4, totalram_bias*4);

    if (totalram_pages > old_totalram_pages)
    {
        //TODO:Just know that totalram_pages will increase.
        total_increase = (totalram_pages - old_totalram_pages) % GB2PAGE;
        if (totalram_bias > total_increase )
        {
            totalram_bias = totalram_bias - total_increase;
        }
        balloon_stats.current_pages = totalram_pages + totalram_bias;
        old_totalram_pages = totalram_pages;
    }
    printk(KERN_INFO "totalram_pages=%luKB, current_pages=%luKB, totalram_bias=%luKB,total_increase=%ld\n", totalram_pages*4, balloon_stats.current_pages*4, totalram_bias*4, total_increase*4);
	xenbus_write(XBT_NIL, "control/uvp", "Balloon_flag", "1");
	do {
		credit = current_target() - balloon_stats.current_pages;
		if (credit > 0)
			need_sleep = (increase_reservation(credit) != 0);
		if (credit < 0)
			need_sleep = (decrease_reservation(-credit) != 0);

#ifndef CONFIG_PREEMPT
		if (need_resched())
			schedule();
#endif
	} while ((credit != 0) && !need_sleep);

	/* Schedule more work if there is some still to be done. */
	if (current_target() != balloon_stats.current_pages)
	{
		mod_timer(&balloon_timer, jiffies + HZ);
		sprintf(buffer,"%lu",balloon_stats.current_pages<<(PAGE_SHIFT-10));
		xenbus_write(XBT_NIL, "memory", "target", buffer);
	}
	xenbus_write(XBT_NIL, "control/uvp", "Balloon_flag", "0");
	mutex_unlock(&balloon_mutex);
}