diff options
author | Ingo Molnar <mingo@elte.hu> | 2010-08-31 09:45:21 +0200 |
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committer | Ingo Molnar <mingo@elte.hu> | 2010-08-31 09:45:46 +0200 |
commit | daab7fc734a53fdeaf844b7c03053118ad1769da (patch) | |
tree | 575deb3cdcc6dda562acaed6f7c29bc81ae01cf2 /arch/x86/xen/mmu.c | |
parent | 774ea0bcb27f57b6fd521b3b6c43237782fed4b9 (diff) | |
parent | 2bfc96a127bc1cc94d26bfaa40159966064f9c8c (diff) |
Merge commit 'v2.6.36-rc3' into x86/memblock
Conflicts:
arch/x86/kernel/trampoline.c
mm/memblock.c
Merge reason: Resolve the conflicts, update to latest upstream.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'arch/x86/xen/mmu.c')
-rw-r--r-- | arch/x86/xen/mmu.c | 328 |
1 files changed, 323 insertions, 5 deletions
diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c index b511f1986911..4fe04ac0bae0 100644 --- a/arch/x86/xen/mmu.c +++ b/arch/x86/xen/mmu.c @@ -42,6 +42,7 @@ #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> @@ -52,14 +53,19 @@ #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" @@ -68,6 +74,13 @@ #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 { @@ -378,6 +391,28 @@ static bool xen_page_pinned(void *ptr) 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; @@ -454,6 +489,11 @@ void set_pte_mfn(unsigned long vaddr, unsigned long mfn, pgprot_t flags) 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); @@ -524,8 +564,25 @@ static pteval_t pte_pfn_to_mfn(pteval_t val) 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); @@ -538,7 +595,22 @@ PV_CALLEE_SAVE_REGS_THUNK(xen_pgd_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); @@ -594,6 +666,11 @@ void xen_set_pud(pud_t *ptr, pud_t val) 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); @@ -610,6 +687,11 @@ void xen_set_pte(pte_t *ptep, pte_t pte) #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)); } @@ -936,8 +1018,6 @@ static int xen_pin_page(struct mm_struct *mm, struct page *page, 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)) { @@ -1501,7 +1581,6 @@ static void xen_alloc_ptpage(struct mm_struct *mm, unsigned long pfn, unsigned l 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) @@ -1812,9 +1891,16 @@ static void xen_set_fixmap(unsigned idx, phys_addr_t phys, pgprot_t prot) 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); @@ -1940,8 +2026,240 @@ void __init xen_init_mmu_ops(void) 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; |