#include <linux/highmem.h>
#include <linux/debugfs.h>
#include <linux/bug.h>
+#include <linux/vmalloc.h>
#include <linux/module.h>
#include <linux/gfp.h>
#include <linux/memblock.h>
#include <asm/mmu_context.h>
#include <asm/setup.h>
#include <asm/paravirt.h>
+#include <asm/e820.h>
#include <asm/linkage.h>
+#include <asm/page.h>
#include <asm/xen/hypercall.h>
#include <asm/xen/hypervisor.h>
+#include <xen/xen.h>
#include <xen/page.h>
#include <xen/interface/xen.h>
+#include <xen/interface/hvm/hvm_op.h>
#include <xen/interface/version.h>
+#include <xen/interface/memory.h>
#include <xen/hvc-console.h>
#include "multicalls.h"
#define MMU_UPDATE_HISTO 30
+/*
+ * Protects atomic reservation decrease/increase against concurrent increases.
+ * Also protects non-atomic updates of current_pages and driver_pages, and
+ * balloon lists.
+ */
+DEFINE_SPINLOCK(xen_reservation_lock);
+
#ifdef CONFIG_XEN_DEBUG_FS
static struct {
return PagePinned(page);
}
+static bool xen_iomap_pte(pte_t pte)
+{
+ return pte_flags(pte) & _PAGE_IOMAP;
+}
+
+static void xen_set_iomap_pte(pte_t *ptep, pte_t pteval)
+{
+ struct multicall_space mcs;
+ struct mmu_update *u;
+
+ mcs = xen_mc_entry(sizeof(*u));
+ u = mcs.args;
+
+ /* ptep might be kmapped when using 32-bit HIGHPTE */
+ u->ptr = arbitrary_virt_to_machine(ptep).maddr;
+ u->val = pte_val_ma(pteval);
+
+ MULTI_mmu_update(mcs.mc, mcs.args, 1, NULL, DOMID_IO);
+
+ xen_mc_issue(PARAVIRT_LAZY_MMU);
+}
+
static void xen_extend_mmu_update(const struct mmu_update *update)
{
struct multicall_space mcs;
void xen_set_pte_at(struct mm_struct *mm, unsigned long addr,
pte_t *ptep, pte_t pteval)
{
+ if (xen_iomap_pte(pteval)) {
+ xen_set_iomap_pte(ptep, pteval);
+ goto out;
+ }
+
ADD_STATS(set_pte_at, 1);
// ADD_STATS(set_pte_at_pinned, xen_page_pinned(ptep));
ADD_STATS(set_pte_at_current, mm == current->mm);
return val;
}
+static pteval_t iomap_pte(pteval_t val)
+{
+ if (val & _PAGE_PRESENT) {
+ unsigned long pfn = (val & PTE_PFN_MASK) >> PAGE_SHIFT;
+ pteval_t flags = val & PTE_FLAGS_MASK;
+
+ /* We assume the pte frame number is a MFN, so
+ just use it as-is. */
+ val = ((pteval_t)pfn << PAGE_SHIFT) | flags;
+ }
+
+ return val;
+}
+
pteval_t xen_pte_val(pte_t pte)
{
+ if (xen_initial_domain() && (pte.pte & _PAGE_IOMAP))
+ return pte.pte;
+
return pte_mfn_to_pfn(pte.pte);
}
PV_CALLEE_SAVE_REGS_THUNK(xen_pte_val);
pte_t xen_make_pte(pteval_t pte)
{
- pte = pte_pfn_to_mfn(pte);
+ phys_addr_t addr = (pte & PTE_PFN_MASK);
+
+ /*
+ * Unprivileged domains are allowed to do IOMAPpings for
+ * PCI passthrough, but not map ISA space. The ISA
+ * mappings are just dummy local mappings to keep other
+ * parts of the kernel happy.
+ */
+ if (unlikely(pte & _PAGE_IOMAP) &&
+ (xen_initial_domain() || addr >= ISA_END_ADDRESS)) {
+ pte = iomap_pte(pte);
+ } else {
+ pte &= ~_PAGE_IOMAP;
+ pte = pte_pfn_to_mfn(pte);
+ }
+
return native_make_pte(pte);
}
PV_CALLEE_SAVE_REGS_THUNK(xen_make_pte);
void xen_set_pte(pte_t *ptep, pte_t pte)
{
+ if (xen_iomap_pte(pte)) {
+ xen_set_iomap_pte(ptep, pte);
+ return;
+ }
+
ADD_STATS(pte_update, 1);
// ADD_STATS(pte_update_pinned, xen_page_pinned(ptep));
ADD_STATS(pte_update_batched, paravirt_get_lazy_mode() == PARAVIRT_LAZY_MMU);
#ifdef CONFIG_X86_PAE
void xen_set_pte_atomic(pte_t *ptep, pte_t pte)
{
+ if (xen_iomap_pte(pte)) {
+ xen_set_iomap_pte(ptep, pte);
+ return;
+ }
+
set_64bit((u64 *)ptep, native_pte_val(pte));
}
read-only, and can be pinned. */
static void __xen_pgd_pin(struct mm_struct *mm, pgd_t *pgd)
{
- vm_unmap_aliases();
-
xen_mc_batch();
if (__xen_pgd_walk(mm, pgd, xen_pin_page, USER_LIMIT)) {
if (PagePinned(virt_to_page(mm->pgd))) {
SetPagePinned(page);
- vm_unmap_aliases();
if (!PageHighMem(page)) {
make_lowmem_page_readonly(__va(PFN_PHYS((unsigned long)pfn)));
if (level == PT_PTE && USE_SPLIT_PTLOCKS)
pte = pfn_pte(phys, prot);
break;
- default:
+ case FIX_PARAVIRT_BOOTMAP:
+ /* This is an MFN, but it isn't an IO mapping from the
+ IO domain */
pte = mfn_pte(phys, prot);
break;
+
+ default:
+ /* By default, set_fixmap is used for hardware mappings */
+ pte = mfn_pte(phys, __pgprot(pgprot_val(prot) | _PAGE_IOMAP));
+ break;
}
__native_set_fixmap(idx, pte);
x86_init.paging.pagetable_setup_start = xen_pagetable_setup_start;
x86_init.paging.pagetable_setup_done = xen_pagetable_setup_done;
pv_mmu_ops = xen_mmu_ops;
+
+ vmap_lazy_unmap = false;
+}
+
+/* Protected by xen_reservation_lock. */
+#define MAX_CONTIG_ORDER 9 /* 2MB */
+static unsigned long discontig_frames[1<<MAX_CONTIG_ORDER];
+
+#define VOID_PTE (mfn_pte(0, __pgprot(0)))
+static void xen_zap_pfn_range(unsigned long vaddr, unsigned int order,
+ unsigned long *in_frames,
+ unsigned long *out_frames)
+{
+ int i;
+ struct multicall_space mcs;
+
+ xen_mc_batch();
+ for (i = 0; i < (1UL<<order); i++, vaddr += PAGE_SIZE) {
+ mcs = __xen_mc_entry(0);
+
+ if (in_frames)
+ in_frames[i] = virt_to_mfn(vaddr);
+
+ MULTI_update_va_mapping(mcs.mc, vaddr, VOID_PTE, 0);
+ set_phys_to_machine(virt_to_pfn(vaddr), INVALID_P2M_ENTRY);
+
+ if (out_frames)
+ out_frames[i] = virt_to_pfn(vaddr);
+ }
+ xen_mc_issue(0);
+}
+
+/*
+ * Update the pfn-to-mfn mappings for a virtual address range, either to
+ * point to an array of mfns, or contiguously from a single starting
+ * mfn.
+ */
+static void xen_remap_exchanged_ptes(unsigned long vaddr, int order,
+ unsigned long *mfns,
+ unsigned long first_mfn)
+{
+ unsigned i, limit;
+ unsigned long mfn;
+
+ xen_mc_batch();
+
+ limit = 1u << order;
+ for (i = 0; i < limit; i++, vaddr += PAGE_SIZE) {
+ struct multicall_space mcs;
+ unsigned flags;
+
+ mcs = __xen_mc_entry(0);
+ if (mfns)
+ mfn = mfns[i];
+ else
+ mfn = first_mfn + i;
+
+ if (i < (limit - 1))
+ flags = 0;
+ else {
+ if (order == 0)
+ flags = UVMF_INVLPG | UVMF_ALL;
+ else
+ flags = UVMF_TLB_FLUSH | UVMF_ALL;
+ }
+
+ MULTI_update_va_mapping(mcs.mc, vaddr,
+ mfn_pte(mfn, PAGE_KERNEL), flags);
+
+ set_phys_to_machine(virt_to_pfn(vaddr), mfn);
+ }
+
+ xen_mc_issue(0);
+}
+
+/*
+ * Perform the hypercall to exchange a region of our pfns to point to
+ * memory with the required contiguous alignment. Takes the pfns as
+ * input, and populates mfns as output.
+ *
+ * Returns a success code indicating whether the hypervisor was able to
+ * satisfy the request or not.
+ */
+static int xen_exchange_memory(unsigned long extents_in, unsigned int order_in,
+ unsigned long *pfns_in,
+ unsigned long extents_out,
+ unsigned int order_out,
+ unsigned long *mfns_out,
+ unsigned int address_bits)
+{
+ long rc;
+ int success;
+
+ struct xen_memory_exchange exchange = {
+ .in = {
+ .nr_extents = extents_in,
+ .extent_order = order_in,
+ .extent_start = pfns_in,
+ .domid = DOMID_SELF
+ },
+ .out = {
+ .nr_extents = extents_out,
+ .extent_order = order_out,
+ .extent_start = mfns_out,
+ .address_bits = address_bits,
+ .domid = DOMID_SELF
+ }
+ };
+
+ BUG_ON(extents_in << order_in != extents_out << order_out);
+
+ rc = HYPERVISOR_memory_op(XENMEM_exchange, &exchange);
+ success = (exchange.nr_exchanged == extents_in);
+
+ BUG_ON(!success && ((exchange.nr_exchanged != 0) || (rc == 0)));
+ BUG_ON(success && (rc != 0));
+
+ return success;
}
+int xen_create_contiguous_region(unsigned long vstart, unsigned int order,
+ unsigned int address_bits)
+{
+ unsigned long *in_frames = discontig_frames, out_frame;
+ unsigned long flags;
+ int success;
+
+ /*
+ * Currently an auto-translated guest will not perform I/O, nor will
+ * it require PAE page directories below 4GB. Therefore any calls to
+ * this function are redundant and can be ignored.
+ */
+
+ if (xen_feature(XENFEAT_auto_translated_physmap))
+ return 0;
+
+ if (unlikely(order > MAX_CONTIG_ORDER))
+ return -ENOMEM;
+
+ memset((void *) vstart, 0, PAGE_SIZE << order);
+
+ spin_lock_irqsave(&xen_reservation_lock, flags);
+
+ /* 1. Zap current PTEs, remembering MFNs. */
+ xen_zap_pfn_range(vstart, order, in_frames, NULL);
+
+ /* 2. Get a new contiguous memory extent. */
+ out_frame = virt_to_pfn(vstart);
+ success = xen_exchange_memory(1UL << order, 0, in_frames,
+ 1, order, &out_frame,
+ address_bits);
+
+ /* 3. Map the new extent in place of old pages. */
+ if (success)
+ xen_remap_exchanged_ptes(vstart, order, NULL, out_frame);
+ else
+ xen_remap_exchanged_ptes(vstart, order, in_frames, 0);
+
+ spin_unlock_irqrestore(&xen_reservation_lock, flags);
+
+ return success ? 0 : -ENOMEM;
+}
+EXPORT_SYMBOL_GPL(xen_create_contiguous_region);
+
+void xen_destroy_contiguous_region(unsigned long vstart, unsigned int order)
+{
+ unsigned long *out_frames = discontig_frames, in_frame;
+ unsigned long flags;
+ int success;
+
+ if (xen_feature(XENFEAT_auto_translated_physmap))
+ return;
+
+ if (unlikely(order > MAX_CONTIG_ORDER))
+ return;
+
+ memset((void *) vstart, 0, PAGE_SIZE << order);
+
+ spin_lock_irqsave(&xen_reservation_lock, flags);
+
+ /* 1. Find start MFN of contiguous extent. */
+ in_frame = virt_to_mfn(vstart);
+
+ /* 2. Zap current PTEs. */
+ xen_zap_pfn_range(vstart, order, NULL, out_frames);
+
+ /* 3. Do the exchange for non-contiguous MFNs. */
+ success = xen_exchange_memory(1, order, &in_frame, 1UL << order,
+ 0, out_frames, 0);
+
+ /* 4. Map new pages in place of old pages. */
+ if (success)
+ xen_remap_exchanged_ptes(vstart, order, out_frames, 0);
+ else
+ xen_remap_exchanged_ptes(vstart, order, NULL, in_frame);
+
+ spin_unlock_irqrestore(&xen_reservation_lock, flags);
+}
+EXPORT_SYMBOL_GPL(xen_destroy_contiguous_region);
+
+#ifdef CONFIG_XEN_PVHVM
+static void xen_hvm_exit_mmap(struct mm_struct *mm)
+{
+ struct xen_hvm_pagetable_dying a;
+ int rc;
+
+ a.domid = DOMID_SELF;
+ a.gpa = __pa(mm->pgd);
+ rc = HYPERVISOR_hvm_op(HVMOP_pagetable_dying, &a);
+ WARN_ON_ONCE(rc < 0);
+}
+
+static int is_pagetable_dying_supported(void)
+{
+ struct xen_hvm_pagetable_dying a;
+ int rc = 0;
+
+ a.domid = DOMID_SELF;
+ a.gpa = 0x00;
+ rc = HYPERVISOR_hvm_op(HVMOP_pagetable_dying, &a);
+ if (rc < 0) {
+ printk(KERN_DEBUG "HVMOP_pagetable_dying not supported\n");
+ return 0;
+ }
+ return 1;
+}
+
+void __init xen_hvm_init_mmu_ops(void)
+{
+ if (is_pagetable_dying_supported())
+ pv_mmu_ops.exit_mmap = xen_hvm_exit_mmap;
+}
+#endif
+
#ifdef CONFIG_XEN_DEBUG_FS
static struct dentry *d_mmu_debug;
git.openpandora.org / pandora-kernel.git / blobdiff