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Diffstat (limited to 'arch/x86/xen/mmu.c')
-rw-r--r--arch/x86/xen/mmu.c74
1 files changed, 70 insertions, 4 deletions
diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c
index f6089421147a..3f6f3347aa17 100644
--- a/arch/x86/xen/mmu.c
+++ b/arch/x86/xen/mmu.c
@@ -46,6 +46,7 @@
#include <linux/module.h>
#include <linux/gfp.h>
#include <linux/memblock.h>
+#include <linux/seq_file.h>
#include <asm/pgtable.h>
#include <asm/tlbflush.h>
@@ -416,8 +417,12 @@ static pteval_t pte_pfn_to_mfn(pteval_t val)
if (val & _PAGE_PRESENT) {
unsigned long pfn = (val & PTE_PFN_MASK) >> PAGE_SHIFT;
pteval_t flags = val & PTE_FLAGS_MASK;
- unsigned long mfn = pfn_to_mfn(pfn);
+ unsigned long mfn;
+ if (!xen_feature(XENFEAT_auto_translated_physmap))
+ mfn = get_phys_to_machine(pfn);
+ else
+ mfn = pfn;
/*
* If there's no mfn for the pfn, then just create an
* empty non-present pte. Unfortunately this loses
@@ -427,8 +432,18 @@ static pteval_t pte_pfn_to_mfn(pteval_t val)
if (unlikely(mfn == INVALID_P2M_ENTRY)) {
mfn = 0;
flags = 0;
+ } else {
+ /*
+ * Paramount to do this test _after_ the
+ * INVALID_P2M_ENTRY as INVALID_P2M_ENTRY &
+ * IDENTITY_FRAME_BIT resolves to true.
+ */
+ mfn &= ~FOREIGN_FRAME_BIT;
+ if (mfn & IDENTITY_FRAME_BIT) {
+ mfn &= ~IDENTITY_FRAME_BIT;
+ flags |= _PAGE_IOMAP;
+ }
}
-
val = ((pteval_t)mfn << PAGE_SHIFT) | flags;
}
@@ -532,6 +547,41 @@ pte_t xen_make_pte(pteval_t pte)
}
PV_CALLEE_SAVE_REGS_THUNK(xen_make_pte);
+#ifdef CONFIG_XEN_DEBUG
+pte_t xen_make_pte_debug(pteval_t pte)
+{
+ phys_addr_t addr = (pte & PTE_PFN_MASK);
+ phys_addr_t other_addr;
+ bool io_page = false;
+ pte_t _pte;
+
+ if (pte & _PAGE_IOMAP)
+ io_page = true;
+
+ _pte = xen_make_pte(pte);
+
+ if (!addr)
+ return _pte;
+
+ if (io_page &&
+ (xen_initial_domain() || addr >= ISA_END_ADDRESS)) {
+ other_addr = pfn_to_mfn(addr >> PAGE_SHIFT) << PAGE_SHIFT;
+ WARN(addr != other_addr,
+ "0x%lx is using VM_IO, but it is 0x%lx!\n",
+ (unsigned long)addr, (unsigned long)other_addr);
+ } else {
+ pteval_t iomap_set = (_pte.pte & PTE_FLAGS_MASK) & _PAGE_IOMAP;
+ other_addr = (_pte.pte & PTE_PFN_MASK);
+ WARN((addr == other_addr) && (!io_page) && (!iomap_set),
+ "0x%lx is missing VM_IO (and wasn't fixed)!\n",
+ (unsigned long)addr);
+ }
+
+ return _pte;
+}
+PV_CALLEE_SAVE_REGS_THUNK(xen_make_pte_debug);
+#endif
+
pgd_t xen_make_pgd(pgdval_t pgd)
{
pgd = pte_pfn_to_mfn(pgd);
@@ -1441,7 +1491,7 @@ static __init pte_t mask_rw_pte(pte_t *ptep, pte_t pte)
* early_ioremap fixmap slot, make sure it is RO.
*/
if (!is_early_ioremap_ptep(ptep) &&
- pfn >= e820_table_start && pfn < e820_table_end)
+ pfn >= pgt_buf_start && pfn < pgt_buf_end)
pte = pte_wrprotect(pte);
return pte;
@@ -1940,6 +1990,9 @@ __init void xen_ident_map_ISA(void)
static __init void xen_post_allocator_init(void)
{
+#ifdef CONFIG_XEN_DEBUG
+ pv_mmu_ops.make_pte = PV_CALLEE_SAVE(xen_make_pte_debug);
+#endif
pv_mmu_ops.set_pte = xen_set_pte;
pv_mmu_ops.set_pmd = xen_set_pmd;
pv_mmu_ops.set_pud = xen_set_pud;
@@ -2072,7 +2125,7 @@ static void xen_zap_pfn_range(unsigned long vaddr, unsigned int order,
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);
+ __set_phys_to_machine(virt_to_pfn(vaddr), INVALID_P2M_ENTRY);
if (out_frames)
out_frames[i] = virt_to_pfn(vaddr);
@@ -2351,6 +2404,18 @@ EXPORT_SYMBOL_GPL(xen_remap_domain_mfn_range);
#ifdef CONFIG_XEN_DEBUG_FS
+static int p2m_dump_open(struct inode *inode, struct file *filp)
+{
+ return single_open(filp, p2m_dump_show, NULL);
+}
+
+static const struct file_operations p2m_dump_fops = {
+ .open = p2m_dump_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
static struct dentry *d_mmu_debug;
static int __init xen_mmu_debugfs(void)
@@ -2406,6 +2471,7 @@ static int __init xen_mmu_debugfs(void)
debugfs_create_u32("prot_commit_batched", 0444, d_mmu_debug,
&mmu_stats.prot_commit_batched);
+ debugfs_create_file("p2m", 0600, d_mmu_debug, NULL, &p2m_dump_fops);
return 0;
}
fs_initcall(xen_mmu_debugfs);