Merge branches 'upstream/xenfs' and 'upstream/core' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen
* 'upstream/xenfs' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen:
xen/privcmd: make privcmd visible in domU
xen/privcmd: move remap_domain_mfn_range() to core xen code and export.
privcmd: MMAPBATCH: Fix error handling/reporting
xenbus: export xen_store_interface for xenfs
xen/privcmd: make sure vma is ours before doing anything to it
xen/privcmd: print SIGBUS faults
xen/xenfs: set_page_dirty is supposed to return true if it dirties
xen/privcmd: create address space to allow writable mmaps
xen: add privcmd driver
xen: add variable hypercall caller
xen: add xen_set_domain_pte()
xen: add /proc/xen/xsd_{kva,port} to xenfs
* 'upstream/core' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen: (29 commits)
xen: include xen/xen.h for definition of xen_initial_domain()
xen: use host E820 map for dom0
xen: correctly rebuild mfn list list after migration.
xen: improvements to VIRQ_DEBUG output
xen: set up IRQ before binding virq to evtchn
xen: ensure that all event channels start off bound to VCPU 0
xen/hvc: only notify if we actually sent something
xen: don't add extra_pages for RAM after mem_end
xen: add support for PAT
xen: make sure xen_max_p2m_pfn is up to date
xen: limit extra memory to a certain ratio of base
xen: add extra pages for E820 RAM regions, even if beyond mem_end
xen: make sure xen_extra_mem_start is beyond all non-RAM e820
xen: implement "extra" memory to reserve space for pages not present at boot
xen: Use host-provided E820 map
xen: don't map missing memory
xen: defer building p2m mfn structures until kernel is mapped
xen: add return value to set_phys_to_machine()
xen: convert p2m to a 3 level tree
xen: make install_p2mtop_page() static
...
Fix up trivial conflict in arch/x86/xen/mmu.c, and fix the use of
'reserve_early()' - in the new memblock world order it is now
'memblock_x86_reserve_range()' instead. Pointed out by Jeremy.
diff --git a/arch/x86/include/asm/xen/hypercall.h b/arch/x86/include/asm/xen/hypercall.h
index 7fda040..a3c28ae 100644
--- a/arch/x86/include/asm/xen/hypercall.h
+++ b/arch/x86/include/asm/xen/hypercall.h
@@ -200,6 +200,23 @@
(type)__res; \
})
+static inline long
+privcmd_call(unsigned call,
+ unsigned long a1, unsigned long a2,
+ unsigned long a3, unsigned long a4,
+ unsigned long a5)
+{
+ __HYPERCALL_DECLS;
+ __HYPERCALL_5ARG(a1, a2, a3, a4, a5);
+
+ asm volatile("call *%[call]"
+ : __HYPERCALL_5PARAM
+ : [call] "a" (&hypercall_page[call])
+ : __HYPERCALL_CLOBBER5);
+
+ return (long)__res;
+}
+
static inline int
HYPERVISOR_set_trap_table(struct trap_info *table)
{
diff --git a/arch/x86/include/asm/xen/page.h b/arch/x86/include/asm/xen/page.h
index bf5f7d3..dd8c141 100644
--- a/arch/x86/include/asm/xen/page.h
+++ b/arch/x86/include/asm/xen/page.h
@@ -37,14 +37,21 @@
extern unsigned long get_phys_to_machine(unsigned long pfn);
-extern void set_phys_to_machine(unsigned long pfn, unsigned long mfn);
+extern bool set_phys_to_machine(unsigned long pfn, unsigned long mfn);
static inline unsigned long pfn_to_mfn(unsigned long pfn)
{
+ unsigned long mfn;
+
if (xen_feature(XENFEAT_auto_translated_physmap))
return pfn;
- return get_phys_to_machine(pfn) & ~FOREIGN_FRAME_BIT;
+ mfn = get_phys_to_machine(pfn);
+
+ if (mfn != INVALID_P2M_ENTRY)
+ mfn &= ~FOREIGN_FRAME_BIT;
+
+ return mfn;
}
static inline int phys_to_machine_mapping_valid(unsigned long pfn)
@@ -159,6 +166,7 @@
#define pgd_val_ma(x) ((x).pgd)
+void xen_set_domain_pte(pte_t *ptep, pte_t pteval, unsigned domid);
xmaddr_t arbitrary_virt_to_machine(void *address);
unsigned long arbitrary_virt_to_mfn(void *vaddr);
diff --git a/arch/x86/xen/Kconfig b/arch/x86/xen/Kconfig
index 68128a1..90a7f5a 100644
--- a/arch/x86/xen/Kconfig
+++ b/arch/x86/xen/Kconfig
@@ -19,15 +19,12 @@
depends on X86_LOCAL_APIC
config XEN_MAX_DOMAIN_MEMORY
- int "Maximum allowed size of a domain in gigabytes"
- default 8 if X86_32
- default 32 if X86_64
+ int
+ default 128
depends on XEN
help
- The pseudo-physical to machine address array is sized
- according to the maximum possible memory size of a Xen
- domain. This array uses 1 page per gigabyte, so there's no
- need to be too stingy here.
+ This only affects the sizing of some bss arrays, the unused
+ portions of which are freed.
config XEN_SAVE_RESTORE
bool
diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index 63b83ce..44ab12d 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -136,9 +136,6 @@
info.mfn = arbitrary_virt_to_mfn(vcpup);
info.offset = offset_in_page(vcpup);
- printk(KERN_DEBUG "trying to map vcpu_info %d at %p, mfn %llx, offset %d\n",
- cpu, vcpup, info.mfn, info.offset);
-
/* Check to see if the hypervisor will put the vcpu_info
structure where we want it, which allows direct access via
a percpu-variable. */
@@ -152,9 +149,6 @@
/* This cpu is using the registered vcpu info, even if
later ones fail to. */
per_cpu(xen_vcpu, cpu) = vcpup;
-
- printk(KERN_DEBUG "cpu %d using vcpu_info at %p\n",
- cpu, vcpup);
}
}
@@ -836,6 +830,11 @@
Xen console noise. */
break;
+ case MSR_IA32_CR_PAT:
+ if (smp_processor_id() == 0)
+ xen_set_pat(((u64)high << 32) | low);
+ break;
+
default:
ret = native_write_msr_safe(msr, low, high);
}
@@ -874,8 +873,6 @@
/* xen_vcpu_setup managed to place the vcpu_info within the
percpu area for all cpus, so make use of it */
if (have_vcpu_info_placement) {
- printk(KERN_INFO "Xen: using vcpu_info placement\n");
-
pv_irq_ops.save_fl = __PV_IS_CALLEE_SAVE(xen_save_fl_direct);
pv_irq_ops.restore_fl = __PV_IS_CALLEE_SAVE(xen_restore_fl_direct);
pv_irq_ops.irq_disable = __PV_IS_CALLEE_SAVE(xen_irq_disable_direct);
@@ -1189,6 +1186,9 @@
xen_raw_console_write("mapping kernel into physical memory\n");
pgd = xen_setup_kernel_pagetable(pgd, xen_start_info->nr_pages);
+ /* Allocate and initialize top and mid mfn levels for p2m structure */
+ xen_build_mfn_list_list();
+
init_mm.pgd = pgd;
/* keep using Xen gdt for now; no urgent need to change it */
diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c
index f72d18c..9631c90 100644
--- a/arch/x86/xen/mmu.c
+++ b/arch/x86/xen/mmu.c
@@ -57,6 +57,7 @@
#include <asm/linkage.h>
#include <asm/page.h>
#include <asm/init.h>
+#include <asm/pat.h>
#include <asm/xen/hypercall.h>
#include <asm/xen/hypervisor.h>
@@ -140,7 +141,8 @@
* large enough to allocate page table pages to allocate the rest.
* Each page can map 2MB.
*/
-static pte_t level1_ident_pgt[PTRS_PER_PTE * 4] __page_aligned_bss;
+#define LEVEL1_IDENT_ENTRIES (PTRS_PER_PTE * 4)
+static RESERVE_BRK_ARRAY(pte_t, level1_ident_pgt, LEVEL1_IDENT_ENTRIES);
#ifdef CONFIG_X86_64
/* l3 pud for userspace vsyscall mapping */
@@ -171,49 +173,182 @@
*/
#define USER_LIMIT ((STACK_TOP_MAX + PGDIR_SIZE - 1) & PGDIR_MASK)
+/*
+ * Xen leaves the responsibility for maintaining p2m mappings to the
+ * guests themselves, but it must also access and update the p2m array
+ * during suspend/resume when all the pages are reallocated.
+ *
+ * The p2m table is logically a flat array, but we implement it as a
+ * three-level tree to allow the address space to be sparse.
+ *
+ * Xen
+ * |
+ * p2m_top p2m_top_mfn
+ * / \ / \
+ * p2m_mid p2m_mid p2m_mid_mfn p2m_mid_mfn
+ * / \ / \ / /
+ * p2m p2m p2m p2m p2m p2m p2m ...
+ *
+ * The p2m_mid_mfn pages are mapped by p2m_top_mfn_p.
+ *
+ * The p2m_top and p2m_top_mfn levels are limited to 1 page, so the
+ * maximum representable pseudo-physical address space is:
+ * P2M_TOP_PER_PAGE * P2M_MID_PER_PAGE * P2M_PER_PAGE pages
+ *
+ * P2M_PER_PAGE depends on the architecture, as a mfn is always
+ * unsigned long (8 bytes on 64-bit, 4 bytes on 32), leading to
+ * 512 and 1024 entries respectively.
+ */
-#define P2M_ENTRIES_PER_PAGE (PAGE_SIZE / sizeof(unsigned long))
-#define TOP_ENTRIES (MAX_DOMAIN_PAGES / P2M_ENTRIES_PER_PAGE)
+unsigned long xen_max_p2m_pfn __read_mostly;
-/* Placeholder for holes in the address space */
-static unsigned long p2m_missing[P2M_ENTRIES_PER_PAGE] __page_aligned_data =
- { [ 0 ... P2M_ENTRIES_PER_PAGE-1 ] = ~0UL };
+#define P2M_PER_PAGE (PAGE_SIZE / sizeof(unsigned long))
+#define P2M_MID_PER_PAGE (PAGE_SIZE / sizeof(unsigned long *))
+#define P2M_TOP_PER_PAGE (PAGE_SIZE / sizeof(unsigned long **))
- /* Array of pointers to pages containing p2m entries */
-static unsigned long *p2m_top[TOP_ENTRIES] __page_aligned_data =
- { [ 0 ... TOP_ENTRIES - 1] = &p2m_missing[0] };
+#define MAX_P2M_PFN (P2M_TOP_PER_PAGE * P2M_MID_PER_PAGE * P2M_PER_PAGE)
-/* Arrays of p2m arrays expressed in mfns used for save/restore */
-static unsigned long p2m_top_mfn[TOP_ENTRIES] __page_aligned_bss;
+/* Placeholders for holes in the address space */
+static RESERVE_BRK_ARRAY(unsigned long, p2m_missing, P2M_PER_PAGE);
+static RESERVE_BRK_ARRAY(unsigned long *, p2m_mid_missing, P2M_MID_PER_PAGE);
+static RESERVE_BRK_ARRAY(unsigned long, p2m_mid_missing_mfn, P2M_MID_PER_PAGE);
-static unsigned long p2m_top_mfn_list[TOP_ENTRIES / P2M_ENTRIES_PER_PAGE]
- __page_aligned_bss;
+static RESERVE_BRK_ARRAY(unsigned long **, p2m_top, P2M_TOP_PER_PAGE);
+static RESERVE_BRK_ARRAY(unsigned long, p2m_top_mfn, P2M_TOP_PER_PAGE);
+static RESERVE_BRK_ARRAY(unsigned long *, p2m_top_mfn_p, P2M_TOP_PER_PAGE);
+
+RESERVE_BRK(p2m_mid, PAGE_SIZE * (MAX_DOMAIN_PAGES / (P2M_PER_PAGE * P2M_MID_PER_PAGE)));
+RESERVE_BRK(p2m_mid_mfn, PAGE_SIZE * (MAX_DOMAIN_PAGES / (P2M_PER_PAGE * P2M_MID_PER_PAGE)));
static inline unsigned p2m_top_index(unsigned long pfn)
{
- BUG_ON(pfn >= MAX_DOMAIN_PAGES);
- return pfn / P2M_ENTRIES_PER_PAGE;
+ BUG_ON(pfn >= MAX_P2M_PFN);
+ return pfn / (P2M_MID_PER_PAGE * P2M_PER_PAGE);
+}
+
+static inline unsigned p2m_mid_index(unsigned long pfn)
+{
+ return (pfn / P2M_PER_PAGE) % P2M_MID_PER_PAGE;
}
static inline unsigned p2m_index(unsigned long pfn)
{
- return pfn % P2M_ENTRIES_PER_PAGE;
+ return pfn % P2M_PER_PAGE;
}
-/* Build the parallel p2m_top_mfn structures */
+static void p2m_top_init(unsigned long ***top)
+{
+ unsigned i;
+
+ for (i = 0; i < P2M_TOP_PER_PAGE; i++)
+ top[i] = p2m_mid_missing;
+}
+
+static void p2m_top_mfn_init(unsigned long *top)
+{
+ unsigned i;
+
+ for (i = 0; i < P2M_TOP_PER_PAGE; i++)
+ top[i] = virt_to_mfn(p2m_mid_missing_mfn);
+}
+
+static void p2m_top_mfn_p_init(unsigned long **top)
+{
+ unsigned i;
+
+ for (i = 0; i < P2M_TOP_PER_PAGE; i++)
+ top[i] = p2m_mid_missing_mfn;
+}
+
+static void p2m_mid_init(unsigned long **mid)
+{
+ unsigned i;
+
+ for (i = 0; i < P2M_MID_PER_PAGE; i++)
+ mid[i] = p2m_missing;
+}
+
+static void p2m_mid_mfn_init(unsigned long *mid)
+{
+ unsigned i;
+
+ for (i = 0; i < P2M_MID_PER_PAGE; i++)
+ mid[i] = virt_to_mfn(p2m_missing);
+}
+
+static void p2m_init(unsigned long *p2m)
+{
+ unsigned i;
+
+ for (i = 0; i < P2M_MID_PER_PAGE; i++)
+ p2m[i] = INVALID_P2M_ENTRY;
+}
+
+/*
+ * Build the parallel p2m_top_mfn and p2m_mid_mfn structures
+ *
+ * This is called both at boot time, and after resuming from suspend:
+ * - At boot time we're called very early, and must use extend_brk()
+ * to allocate memory.
+ *
+ * - After resume we're called from within stop_machine, but the mfn
+ * tree should alreay be completely allocated.
+ */
void xen_build_mfn_list_list(void)
{
- unsigned pfn, idx;
+ unsigned long pfn;
- for (pfn = 0; pfn < MAX_DOMAIN_PAGES; pfn += P2M_ENTRIES_PER_PAGE) {
- unsigned topidx = p2m_top_index(pfn);
+ /* Pre-initialize p2m_top_mfn to be completely missing */
+ if (p2m_top_mfn == NULL) {
+ p2m_mid_missing_mfn = extend_brk(PAGE_SIZE, PAGE_SIZE);
+ p2m_mid_mfn_init(p2m_mid_missing_mfn);
- p2m_top_mfn[topidx] = virt_to_mfn(p2m_top[topidx]);
+ p2m_top_mfn_p = extend_brk(PAGE_SIZE, PAGE_SIZE);
+ p2m_top_mfn_p_init(p2m_top_mfn_p);
+
+ p2m_top_mfn = extend_brk(PAGE_SIZE, PAGE_SIZE);
+ p2m_top_mfn_init(p2m_top_mfn);
+ } else {
+ /* Reinitialise, mfn's all change after migration */
+ p2m_mid_mfn_init(p2m_mid_missing_mfn);
}
- for (idx = 0; idx < ARRAY_SIZE(p2m_top_mfn_list); idx++) {
- unsigned topidx = idx * P2M_ENTRIES_PER_PAGE;
- p2m_top_mfn_list[idx] = virt_to_mfn(&p2m_top_mfn[topidx]);
+ for (pfn = 0; pfn < xen_max_p2m_pfn; pfn += P2M_PER_PAGE) {
+ unsigned topidx = p2m_top_index(pfn);
+ unsigned mididx = p2m_mid_index(pfn);
+ unsigned long **mid;
+ unsigned long *mid_mfn_p;
+
+ mid = p2m_top[topidx];
+ mid_mfn_p = p2m_top_mfn_p[topidx];
+
+ /* Don't bother allocating any mfn mid levels if
+ * they're just missing, just update the stored mfn,
+ * since all could have changed over a migrate.
+ */
+ if (mid == p2m_mid_missing) {
+ BUG_ON(mididx);
+ BUG_ON(mid_mfn_p != p2m_mid_missing_mfn);
+ p2m_top_mfn[topidx] = virt_to_mfn(p2m_mid_missing_mfn);
+ pfn += (P2M_MID_PER_PAGE - 1) * P2M_PER_PAGE;
+ continue;
+ }
+
+ if (mid_mfn_p == p2m_mid_missing_mfn) {
+ /*
+ * XXX boot-time only! We should never find
+ * missing parts of the mfn tree after
+ * runtime. extend_brk() will BUG if we call
+ * it too late.
+ */
+ mid_mfn_p = extend_brk(PAGE_SIZE, PAGE_SIZE);
+ p2m_mid_mfn_init(mid_mfn_p);
+
+ p2m_top_mfn_p[topidx] = mid_mfn_p;
+ }
+
+ p2m_top_mfn[topidx] = virt_to_mfn(mid_mfn_p);
+ mid_mfn_p[mididx] = virt_to_mfn(mid[mididx]);
}
}
@@ -222,8 +357,8 @@
BUG_ON(HYPERVISOR_shared_info == &xen_dummy_shared_info);
HYPERVISOR_shared_info->arch.pfn_to_mfn_frame_list_list =
- virt_to_mfn(p2m_top_mfn_list);
- HYPERVISOR_shared_info->arch.max_pfn = xen_start_info->nr_pages;
+ virt_to_mfn(p2m_top_mfn);
+ HYPERVISOR_shared_info->arch.max_pfn = xen_max_p2m_pfn;
}
/* Set up p2m_top to point to the domain-builder provided p2m pages */
@@ -231,98 +366,176 @@
{
unsigned long *mfn_list = (unsigned long *)xen_start_info->mfn_list;
unsigned long max_pfn = min(MAX_DOMAIN_PAGES, xen_start_info->nr_pages);
- unsigned pfn;
+ unsigned long pfn;
- for (pfn = 0; pfn < max_pfn; pfn += P2M_ENTRIES_PER_PAGE) {
+ xen_max_p2m_pfn = max_pfn;
+
+ p2m_missing = extend_brk(PAGE_SIZE, PAGE_SIZE);
+ p2m_init(p2m_missing);
+
+ p2m_mid_missing = extend_brk(PAGE_SIZE, PAGE_SIZE);
+ p2m_mid_init(p2m_mid_missing);
+
+ p2m_top = extend_brk(PAGE_SIZE, PAGE_SIZE);
+ p2m_top_init(p2m_top);
+
+ /*
+ * The domain builder gives us a pre-constructed p2m array in
+ * mfn_list for all the pages initially given to us, so we just
+ * need to graft that into our tree structure.
+ */
+ for (pfn = 0; pfn < max_pfn; pfn += P2M_PER_PAGE) {
unsigned topidx = p2m_top_index(pfn);
+ unsigned mididx = p2m_mid_index(pfn);
- p2m_top[topidx] = &mfn_list[pfn];
+ if (p2m_top[topidx] == p2m_mid_missing) {
+ unsigned long **mid = extend_brk(PAGE_SIZE, PAGE_SIZE);
+ p2m_mid_init(mid);
+
+ p2m_top[topidx] = mid;
+ }
+
+ p2m_top[topidx][mididx] = &mfn_list[pfn];
}
-
- xen_build_mfn_list_list();
}
unsigned long get_phys_to_machine(unsigned long pfn)
{
- unsigned topidx, idx;
+ unsigned topidx, mididx, idx;
- if (unlikely(pfn >= MAX_DOMAIN_PAGES))
+ if (unlikely(pfn >= MAX_P2M_PFN))
return INVALID_P2M_ENTRY;
topidx = p2m_top_index(pfn);
+ mididx = p2m_mid_index(pfn);
idx = p2m_index(pfn);
- return p2m_top[topidx][idx];
+
+ return p2m_top[topidx][mididx][idx];
}
EXPORT_SYMBOL_GPL(get_phys_to_machine);
-/* install a new p2m_top page */
-bool install_p2mtop_page(unsigned long pfn, unsigned long *p)
+static void *alloc_p2m_page(void)
{
- unsigned topidx = p2m_top_index(pfn);
- unsigned long **pfnp, *mfnp;
- unsigned i;
-
- pfnp = &p2m_top[topidx];
- mfnp = &p2m_top_mfn[topidx];
-
- for (i = 0; i < P2M_ENTRIES_PER_PAGE; i++)
- p[i] = INVALID_P2M_ENTRY;
-
- if (cmpxchg(pfnp, p2m_missing, p) == p2m_missing) {
- *mfnp = virt_to_mfn(p);
- return true;
- }
-
- return false;
+ return (void *)__get_free_page(GFP_KERNEL | __GFP_REPEAT);
}
-static void alloc_p2m(unsigned long pfn)
+static void free_p2m_page(void *p)
{
- unsigned long *p;
+ free_page((unsigned long)p);
+}
- p = (void *)__get_free_page(GFP_KERNEL | __GFP_NOFAIL);
- BUG_ON(p == NULL);
+/*
+ * Fully allocate the p2m structure for a given pfn. We need to check
+ * that both the top and mid levels are allocated, and make sure the
+ * parallel mfn tree is kept in sync. We may race with other cpus, so
+ * the new pages are installed with cmpxchg; if we lose the race then
+ * simply free the page we allocated and use the one that's there.
+ */
+static bool alloc_p2m(unsigned long pfn)
+{
+ unsigned topidx, mididx;
+ unsigned long ***top_p, **mid;
+ unsigned long *top_mfn_p, *mid_mfn;
- if (!install_p2mtop_page(pfn, p))
- free_page((unsigned long)p);
+ topidx = p2m_top_index(pfn);
+ mididx = p2m_mid_index(pfn);
+
+ top_p = &p2m_top[topidx];
+ mid = *top_p;
+
+ if (mid == p2m_mid_missing) {
+ /* Mid level is missing, allocate a new one */
+ mid = alloc_p2m_page();
+ if (!mid)
+ return false;
+
+ p2m_mid_init(mid);
+
+ if (cmpxchg(top_p, p2m_mid_missing, mid) != p2m_mid_missing)
+ free_p2m_page(mid);
+ }
+
+ top_mfn_p = &p2m_top_mfn[topidx];
+ mid_mfn = p2m_top_mfn_p[topidx];
+
+ BUG_ON(virt_to_mfn(mid_mfn) != *top_mfn_p);
+
+ if (mid_mfn == p2m_mid_missing_mfn) {
+ /* Separately check the mid mfn level */
+ unsigned long missing_mfn;
+ unsigned long mid_mfn_mfn;
+
+ mid_mfn = alloc_p2m_page();
+ if (!mid_mfn)
+ return false;
+
+ p2m_mid_mfn_init(mid_mfn);
+
+ missing_mfn = virt_to_mfn(p2m_mid_missing_mfn);
+ mid_mfn_mfn = virt_to_mfn(mid_mfn);
+ if (cmpxchg(top_mfn_p, missing_mfn, mid_mfn_mfn) != missing_mfn)
+ free_p2m_page(mid_mfn);
+ else
+ p2m_top_mfn_p[topidx] = mid_mfn;
+ }
+
+ if (p2m_top[topidx][mididx] == p2m_missing) {
+ /* p2m leaf page is missing */
+ unsigned long *p2m;
+
+ p2m = alloc_p2m_page();
+ if (!p2m)
+ return false;
+
+ p2m_init(p2m);
+
+ if (cmpxchg(&mid[mididx], p2m_missing, p2m) != p2m_missing)
+ free_p2m_page(p2m);
+ else
+ mid_mfn[mididx] = virt_to_mfn(p2m);
+ }
+
+ return true;
}
/* Try to install p2m mapping; fail if intermediate bits missing */
bool __set_phys_to_machine(unsigned long pfn, unsigned long mfn)
{
- unsigned topidx, idx;
+ unsigned topidx, mididx, idx;
- if (unlikely(pfn >= MAX_DOMAIN_PAGES)) {
+ if (unlikely(pfn >= MAX_P2M_PFN)) {
BUG_ON(mfn != INVALID_P2M_ENTRY);
return true;
}
topidx = p2m_top_index(pfn);
- if (p2m_top[topidx] == p2m_missing) {
- if (mfn == INVALID_P2M_ENTRY)
- return true;
- return false;
- }
-
+ mididx = p2m_mid_index(pfn);
idx = p2m_index(pfn);
- p2m_top[topidx][idx] = mfn;
+
+ if (p2m_top[topidx][mididx] == p2m_missing)
+ return mfn == INVALID_P2M_ENTRY;
+
+ p2m_top[topidx][mididx][idx] = mfn;
return true;
}
-void set_phys_to_machine(unsigned long pfn, unsigned long mfn)
+bool set_phys_to_machine(unsigned long pfn, unsigned long mfn)
{
if (unlikely(xen_feature(XENFEAT_auto_translated_physmap))) {
BUG_ON(pfn != mfn && mfn != INVALID_P2M_ENTRY);
- return;
+ return true;
}
if (unlikely(!__set_phys_to_machine(pfn, mfn))) {
- alloc_p2m(pfn);
+ if (!alloc_p2m(pfn))
+ return false;
if (!__set_phys_to_machine(pfn, mfn))
- BUG();
+ return false;
}
+
+ return true;
}
unsigned long arbitrary_virt_to_mfn(void *vaddr)
@@ -399,7 +612,7 @@
return pte_flags(pte) & _PAGE_IOMAP;
}
-static void xen_set_iomap_pte(pte_t *ptep, pte_t pteval)
+void xen_set_domain_pte(pte_t *ptep, pte_t pteval, unsigned domid)
{
struct multicall_space mcs;
struct mmu_update *u;
@@ -411,10 +624,16 @@
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);
+ MULTI_mmu_update(mcs.mc, mcs.args, 1, NULL, domid);
xen_mc_issue(PARAVIRT_LAZY_MMU);
}
+EXPORT_SYMBOL_GPL(xen_set_domain_pte);
+
+static void xen_set_iomap_pte(pte_t *ptep, pte_t pteval)
+{
+ xen_set_domain_pte(ptep, pteval, DOMID_IO);
+}
static void xen_extend_mmu_update(const struct mmu_update *update)
{
@@ -561,7 +780,20 @@
if (val & _PAGE_PRESENT) {
unsigned long pfn = (val & PTE_PFN_MASK) >> PAGE_SHIFT;
pteval_t flags = val & PTE_FLAGS_MASK;
- val = ((pteval_t)pfn_to_mfn(pfn) << PAGE_SHIFT) | flags;
+ unsigned long mfn = pfn_to_mfn(pfn);
+
+ /*
+ * If there's no mfn for the pfn, then just create an
+ * empty non-present pte. Unfortunately this loses
+ * information about the original pfn, so
+ * pte_mfn_to_pfn is asymmetric.
+ */
+ if (unlikely(mfn == INVALID_P2M_ENTRY)) {
+ mfn = 0;
+ flags = 0;
+ }
+
+ val = ((pteval_t)mfn << PAGE_SHIFT) | flags;
}
return val;
@@ -583,10 +815,18 @@
pteval_t xen_pte_val(pte_t pte)
{
- if (xen_initial_domain() && (pte.pte & _PAGE_IOMAP))
- return pte.pte;
+ pteval_t pteval = pte.pte;
- return pte_mfn_to_pfn(pte.pte);
+ /* If this is a WC pte, convert back from Xen WC to Linux WC */
+ if ((pteval & (_PAGE_PAT | _PAGE_PCD | _PAGE_PWT)) == _PAGE_PAT) {
+ WARN_ON(!pat_enabled);
+ pteval = (pteval & ~_PAGE_PAT) | _PAGE_PWT;
+ }
+
+ if (xen_initial_domain() && (pteval & _PAGE_IOMAP))
+ return pteval;
+
+ return pte_mfn_to_pfn(pteval);
}
PV_CALLEE_SAVE_REGS_THUNK(xen_pte_val);
@@ -596,10 +836,48 @@
}
PV_CALLEE_SAVE_REGS_THUNK(xen_pgd_val);
+/*
+ * Xen's PAT setup is part of its ABI, though I assume entries 6 & 7
+ * are reserved for now, to correspond to the Intel-reserved PAT
+ * types.
+ *
+ * We expect Linux's PAT set as follows:
+ *
+ * Idx PTE flags Linux Xen Default
+ * 0 WB WB WB
+ * 1 PWT WC WT WT
+ * 2 PCD UC- UC- UC-
+ * 3 PCD PWT UC UC UC
+ * 4 PAT WB WC WB
+ * 5 PAT PWT WC WP WT
+ * 6 PAT PCD UC- UC UC-
+ * 7 PAT PCD PWT UC UC UC
+ */
+
+void xen_set_pat(u64 pat)
+{
+ /* We expect Linux to use a PAT setting of
+ * UC UC- WC WB (ignoring the PAT flag) */
+ WARN_ON(pat != 0x0007010600070106ull);
+}
+
pte_t xen_make_pte(pteval_t pte)
{
phys_addr_t addr = (pte & PTE_PFN_MASK);
+ /* If Linux is trying to set a WC pte, then map to the Xen WC.
+ * If _PAGE_PAT is set, then it probably means it is really
+ * _PAGE_PSE, so avoid fiddling with the PAT mapping and hope
+ * things work out OK...
+ *
+ * (We should never see kernel mappings with _PAGE_PSE set,
+ * but we could see hugetlbfs mappings, I think.).
+ */
+ if (pat_enabled && !WARN_ON(pte & _PAGE_PAT)) {
+ if ((pte & (_PAGE_PCD | _PAGE_PWT)) == _PAGE_PWT)
+ pte = (pte & ~(_PAGE_PCD | _PAGE_PWT)) | _PAGE_PAT;
+ }
+
/*
* Unprivileged domains are allowed to do IOMAPpings for
* PCI passthrough, but not map ISA space. The ISA
@@ -1712,6 +1990,9 @@
unsigned ident_pte;
unsigned long pfn;
+ level1_ident_pgt = extend_brk(sizeof(pte_t) * LEVEL1_IDENT_ENTRIES,
+ PAGE_SIZE);
+
ident_pte = 0;
pfn = 0;
for (pmdidx = 0; pmdidx < PTRS_PER_PMD && pfn < max_pfn; pmdidx++) {
@@ -1722,7 +2003,7 @@
pte_page = m2v(pmd[pmdidx].pmd);
else {
/* Check for free pte pages */
- if (ident_pte == ARRAY_SIZE(level1_ident_pgt))
+ if (ident_pte == LEVEL1_IDENT_ENTRIES)
break;
pte_page = &level1_ident_pgt[ident_pte];
@@ -1837,13 +2118,15 @@
return pgd;
}
#else /* !CONFIG_X86_64 */
-static pmd_t level2_kernel_pgt[PTRS_PER_PMD] __page_aligned_bss;
+static RESERVE_BRK_ARRAY(pmd_t, level2_kernel_pgt, PTRS_PER_PMD);
__init pgd_t *xen_setup_kernel_pagetable(pgd_t *pgd,
unsigned long max_pfn)
{
pmd_t *kernel_pmd;
+ level2_kernel_pgt = extend_brk(sizeof(pmd_t *) * PTRS_PER_PMD, PAGE_SIZE);
+
max_pfn_mapped = PFN_DOWN(__pa(xen_start_info->pt_base) +
xen_start_info->nr_pt_frames * PAGE_SIZE +
512*1024);
@@ -2269,6 +2552,72 @@
}
#endif
+#define REMAP_BATCH_SIZE 16
+
+struct remap_data {
+ unsigned long mfn;
+ pgprot_t prot;
+ struct mmu_update *mmu_update;
+};
+
+static int remap_area_mfn_pte_fn(pte_t *ptep, pgtable_t token,
+ unsigned long addr, void *data)
+{
+ struct remap_data *rmd = data;
+ pte_t pte = pte_mkspecial(pfn_pte(rmd->mfn++, rmd->prot));
+
+ rmd->mmu_update->ptr = arbitrary_virt_to_machine(ptep).maddr;
+ rmd->mmu_update->val = pte_val_ma(pte);
+ rmd->mmu_update++;
+
+ return 0;
+}
+
+int xen_remap_domain_mfn_range(struct vm_area_struct *vma,
+ unsigned long addr,
+ unsigned long mfn, int nr,
+ pgprot_t prot, unsigned domid)
+{
+ struct remap_data rmd;
+ struct mmu_update mmu_update[REMAP_BATCH_SIZE];
+ int batch;
+ unsigned long range;
+ int err = 0;
+
+ prot = __pgprot(pgprot_val(prot) | _PAGE_IOMAP);
+
+ vma->vm_flags |= VM_IO | VM_RESERVED | VM_PFNMAP;
+
+ rmd.mfn = mfn;
+ rmd.prot = prot;
+
+ while (nr) {
+ batch = min(REMAP_BATCH_SIZE, nr);
+ range = (unsigned long)batch << PAGE_SHIFT;
+
+ rmd.mmu_update = mmu_update;
+ err = apply_to_page_range(vma->vm_mm, addr, range,
+ remap_area_mfn_pte_fn, &rmd);
+ if (err)
+ goto out;
+
+ err = -EFAULT;
+ if (HYPERVISOR_mmu_update(mmu_update, batch, NULL, domid) < 0)
+ goto out;
+
+ nr -= batch;
+ addr += range;
+ }
+
+ err = 0;
+out:
+
+ flush_tlb_all();
+
+ return err;
+}
+EXPORT_SYMBOL_GPL(xen_remap_domain_mfn_range);
+
#ifdef CONFIG_XEN_DEBUG_FS
static struct dentry *d_mmu_debug;
diff --git a/arch/x86/xen/mmu.h b/arch/x86/xen/mmu.h
index fa938c4..537bb9a 100644
--- a/arch/x86/xen/mmu.h
+++ b/arch/x86/xen/mmu.h
@@ -12,7 +12,6 @@
bool __set_phys_to_machine(unsigned long pfn, unsigned long mfn);
-bool install_p2mtop_page(unsigned long pfn, unsigned long *p);
void set_pte_mfn(unsigned long vaddr, unsigned long pfn, pgprot_t flags);
diff --git a/arch/x86/xen/setup.c b/arch/x86/xen/setup.c
index 9729c90..105db25 100644
--- a/arch/x86/xen/setup.c
+++ b/arch/x86/xen/setup.c
@@ -18,8 +18,10 @@
#include <asm/xen/hypervisor.h>
#include <asm/xen/hypercall.h>
+#include <xen/xen.h>
#include <xen/page.h>
#include <xen/interface/callback.h>
+#include <xen/interface/memory.h>
#include <xen/interface/physdev.h>
#include <xen/interface/memory.h>
#include <xen/features.h>
@@ -34,6 +36,39 @@
extern void xen_syscall_target(void);
extern void xen_syscall32_target(void);
+/* Amount of extra memory space we add to the e820 ranges */
+phys_addr_t xen_extra_mem_start, xen_extra_mem_size;
+
+/*
+ * The maximum amount of extra memory compared to the base size. The
+ * main scaling factor is the size of struct page. At extreme ratios
+ * of base:extra, all the base memory can be filled with page
+ * structures for the extra memory, leaving no space for anything
+ * else.
+ *
+ * 10x seems like a reasonable balance between scaling flexibility and
+ * leaving a practically usable system.
+ */
+#define EXTRA_MEM_RATIO (10)
+
+static __init void xen_add_extra_mem(unsigned long pages)
+{
+ u64 size = (u64)pages * PAGE_SIZE;
+ u64 extra_start = xen_extra_mem_start + xen_extra_mem_size;
+
+ if (!pages)
+ return;
+
+ e820_add_region(extra_start, size, E820_RAM);
+ sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
+
+ memblock_x86_reserve_range(extra_start, extra_start + size, "XEN EXTRA");
+
+ xen_extra_mem_size += size;
+
+ xen_max_p2m_pfn = PFN_DOWN(extra_start + size);
+}
+
static unsigned long __init xen_release_chunk(phys_addr_t start_addr,
phys_addr_t end_addr)
{
@@ -105,16 +140,65 @@
/**
* machine_specific_memory_setup - Hook for machine specific memory setup.
**/
-
char * __init xen_memory_setup(void)
{
+ static struct e820entry map[E820MAX] __initdata;
+
unsigned long max_pfn = xen_start_info->nr_pages;
+ unsigned long long mem_end;
+ int rc;
+ struct xen_memory_map memmap;
+ unsigned long extra_pages = 0;
+ unsigned long extra_limit;
+ int i;
+ int op;
max_pfn = min(MAX_DOMAIN_PAGES, max_pfn);
+ mem_end = PFN_PHYS(max_pfn);
+
+ memmap.nr_entries = E820MAX;
+ set_xen_guest_handle(memmap.buffer, map);
+
+ op = xen_initial_domain() ?
+ XENMEM_machine_memory_map :
+ XENMEM_memory_map;
+ rc = HYPERVISOR_memory_op(op, &memmap);
+ if (rc == -ENOSYS) {
+ memmap.nr_entries = 1;
+ map[0].addr = 0ULL;
+ map[0].size = mem_end;
+ /* 8MB slack (to balance backend allocations). */
+ map[0].size += 8ULL << 20;
+ map[0].type = E820_RAM;
+ rc = 0;
+ }
+ BUG_ON(rc);
e820.nr_map = 0;
+ xen_extra_mem_start = mem_end;
+ for (i = 0; i < memmap.nr_entries; i++) {
+ unsigned long long end = map[i].addr + map[i].size;
- e820_add_region(0, PFN_PHYS((u64)max_pfn), E820_RAM);
+ if (map[i].type == E820_RAM) {
+ if (map[i].addr < mem_end && end > mem_end) {
+ /* Truncate region to max_mem. */
+ u64 delta = end - mem_end;
+
+ map[i].size -= delta;
+ extra_pages += PFN_DOWN(delta);
+
+ end = mem_end;
+ }
+ }
+
+ if (end > xen_extra_mem_start)
+ xen_extra_mem_start = end;
+
+ /* If region is non-RAM or below mem_end, add what remains */
+ if ((map[i].type != E820_RAM || map[i].addr < mem_end) &&
+ map[i].size > 0)
+ e820_add_region(map[i].addr, map[i].size, map[i].type);
+ }
/*
* Even though this is normal, usable memory under Xen, reserve
@@ -136,7 +220,29 @@
sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
- xen_return_unused_memory(xen_start_info->nr_pages, &e820);
+ extra_pages += xen_return_unused_memory(xen_start_info->nr_pages, &e820);
+
+ /*
+ * Clamp the amount of extra memory to a EXTRA_MEM_RATIO
+ * factor the base size. On non-highmem systems, the base
+ * size is the full initial memory allocation; on highmem it
+ * is limited to the max size of lowmem, so that it doesn't
+ * get completely filled.
+ *
+ * In principle there could be a problem in lowmem systems if
+ * the initial memory is also very large with respect to
+ * lowmem, but we won't try to deal with that here.
+ */
+ extra_limit = min(EXTRA_MEM_RATIO * min(max_pfn, PFN_DOWN(MAXMEM)),
+ max_pfn + extra_pages);
+
+ if (extra_limit >= max_pfn)
+ extra_pages = extra_limit - max_pfn;
+ else
+ extra_pages = 0;
+
+ if (!xen_initial_domain())
+ xen_add_extra_mem(extra_pages);
return "Xen";
}
diff --git a/arch/x86/xen/xen-ops.h b/arch/x86/xen/xen-ops.h
index 7c8ab86..6404474 100644
--- a/arch/x86/xen/xen-ops.h
+++ b/arch/x86/xen/xen-ops.h
@@ -30,6 +30,9 @@
pgd_t *xen_setup_kernel_pagetable(pgd_t *pgd, unsigned long max_pfn);
void xen_ident_map_ISA(void);
void xen_reserve_top(void);
+extern unsigned long xen_max_p2m_pfn;
+
+void xen_set_pat(u64);
char * __init xen_memory_setup(void);
void __init xen_arch_setup(void);