Merge branch 'master' into x86/memblock
authorTejun Heo <tj@kernel.org>
Mon, 28 Nov 2011 17:46:22 +0000 (09:46 -0800)
committerTejun Heo <tj@kernel.org>
Mon, 28 Nov 2011 17:46:22 +0000 (09:46 -0800)
Conflicts & resolutions:

* arch/x86/xen/setup.c

dc91c728fd "xen: allow extra memory to be in multiple regions"
24aa07882b "memblock, x86: Replace memblock_x86_reserve/free..."

conflicted on xen_add_extra_mem() updates.  The resolution is
trivial as the latter just want to replace
memblock_x86_reserve_range() with memblock_reserve().

* drivers/pci/intel-iommu.c

166e9278a3f "x86/ia64: intel-iommu: move to drivers/iommu/"
5dfe8660a3d "bootmem: Replace work_with_active_regions() with..."

conflicted as the former moved the file under drivers/iommu/.
Resolved by applying the chnages from the latter on the moved
file.

* mm/Kconfig

6661672053a "memblock: add NO_BOOTMEM config symbol"
c378ddd53f9 "memblock, x86: Make ARCH_DISCARD_MEMBLOCK a config option"

conflicted trivially.  Both added config options.  Just
letting both add their own options resolves the conflict.

* mm/memblock.c

d1f0ece6cdc "mm/memblock.c: small function definition fixes"
ed7b56a799c "memblock: Remove memblock_memory_can_coalesce()"

confliected.  The former updates function removed by the
latter.  Resolution is trivial.

Signed-off-by: Tejun Heo <tj@kernel.org>
18 files changed:
1  2 
arch/powerpc/mm/numa.c
arch/sparc/mm/init_64.c
arch/x86/Kconfig
arch/x86/kernel/e820.c
arch/x86/kernel/setup.c
arch/x86/mm/init.c
arch/x86/mm/init_64.c
arch/x86/platform/efi/efi.c
arch/x86/xen/mmu.c
arch/x86/xen/setup.c
drivers/iommu/intel-iommu.c
include/linux/memblock.h
include/linux/mm.h
kernel/printk.c
mm/Kconfig
mm/memblock.c
mm/nobootmem.c
mm/page_alloc.c

Simple merge
Simple merge
Simple merge
Simple merge
Simple merge
index 0b736b99d92555537d6656384f6704864983483b,87488b93a65ce19695947bc6ca7f58f948e0f24b..a298914058f9c98ebeaba6a84725f7310a1e6f5d
@@@ -63,12 -63,11 +63,11 @@@ static void __init find_early_table_spa
  #ifdef CONFIG_X86_32
        /* for fixmap */
        tables += roundup(__end_of_fixed_addresses * sizeof(pte_t), PAGE_SIZE);
-       good_end = max_pfn_mapped << PAGE_SHIFT;
  #endif
+       good_end = max_pfn_mapped << PAGE_SHIFT;
  
        base = memblock_find_in_range(start, good_end, tables, PAGE_SIZE);
 -      if (base == MEMBLOCK_ERROR)
 +      if (!base)
                panic("Cannot find space for the kernel page tables");
  
        pgt_buf_start = base >> PAGE_SHIFT;
Simple merge
Simple merge
Simple merge
index 73daaf75801aae1275241569d13d01f0a122a04d,38d0af4fefec19f52d5e724c8f08102d391dc2e6..f5e1362550e76130eb4b770e926825ec76cb56f1
@@@ -50,26 -54,32 +54,32 @@@ unsigned long xen_released_pages
   */
  #define EXTRA_MEM_RATIO               (10)
  
- static void __init xen_add_extra_mem(unsigned long pages)
+ static void __init xen_add_extra_mem(u64 start, u64 size)
  {
        unsigned long pfn;
+       int i;
  
-       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_reserve(extra_start, size);
+       for (i = 0; i < XEN_EXTRA_MEM_MAX_REGIONS; i++) {
+               /* Add new region. */
+               if (xen_extra_mem[i].size == 0) {
+                       xen_extra_mem[i].start = start;
+                       xen_extra_mem[i].size  = size;
+                       break;
+               }
+               /* Append to existing region. */
+               if (xen_extra_mem[i].start + xen_extra_mem[i].size == start) {
+                       xen_extra_mem[i].size += size;
+                       break;
+               }
+       }
+       if (i == XEN_EXTRA_MEM_MAX_REGIONS)
+               printk(KERN_WARNING "Warning: not enough extra memory regions\n");
  
-       xen_extra_mem_size += size;
 -      memblock_x86_reserve_range(start, start + size, "XEN EXTRA");
++      memblock_reserve(start, size);
  
-       xen_max_p2m_pfn = PFN_DOWN(extra_start + size);
+       xen_max_p2m_pfn = PFN_DOWN(start + size);
  
-       for (pfn = PFN_DOWN(extra_start); pfn <= xen_max_p2m_pfn; pfn++)
+       for (pfn = PFN_DOWN(start); pfn <= xen_max_p2m_pfn; pfn++)
                __set_phys_to_machine(pfn, INVALID_P2M_ENTRY);
  }
  
index 0000000000000000000000000000000000000000,c0c7820d4c46b406465e0d2d8e059a80ce819476..bcbd693b351ae8f250496388ff5f0921a90b0be6
mode 000000,100644..100644
--- /dev/null
@@@ -1,0 -1,4179 +1,4173 @@@
 -static int __init si_domain_work_fn(unsigned long start_pfn,
 -                                  unsigned long end_pfn, void *datax)
 -{
 -      int *ret = datax;
 -
 -      *ret = iommu_domain_identity_map(si_domain,
 -                                       (uint64_t)start_pfn << PAGE_SHIFT,
 -                                       (uint64_t)end_pfn << PAGE_SHIFT);
 -      return *ret;
 -
 -}
 -
+ /*
+  * Copyright (c) 2006, Intel Corporation.
+  *
+  * This program is free software; you can redistribute it and/or modify it
+  * under the terms and conditions of the GNU General Public License,
+  * version 2, as published by the Free Software Foundation.
+  *
+  * This program is distributed in the hope it will be useful, but WITHOUT
+  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+  * more details.
+  *
+  * You should have received a copy of the GNU General Public License along with
+  * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+  * Place - Suite 330, Boston, MA 02111-1307 USA.
+  *
+  * Copyright (C) 2006-2008 Intel Corporation
+  * Author: Ashok Raj <ashok.raj@intel.com>
+  * Author: Shaohua Li <shaohua.li@intel.com>
+  * Author: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
+  * Author: Fenghua Yu <fenghua.yu@intel.com>
+  */
+ #include <linux/init.h>
+ #include <linux/bitmap.h>
+ #include <linux/debugfs.h>
+ #include <linux/export.h>
+ #include <linux/slab.h>
+ #include <linux/irq.h>
+ #include <linux/interrupt.h>
+ #include <linux/spinlock.h>
+ #include <linux/pci.h>
+ #include <linux/dmar.h>
+ #include <linux/dma-mapping.h>
+ #include <linux/mempool.h>
+ #include <linux/timer.h>
+ #include <linux/iova.h>
+ #include <linux/iommu.h>
+ #include <linux/intel-iommu.h>
+ #include <linux/syscore_ops.h>
+ #include <linux/tboot.h>
+ #include <linux/dmi.h>
+ #include <linux/pci-ats.h>
+ #include <asm/cacheflush.h>
+ #include <asm/iommu.h>
+ #define ROOT_SIZE             VTD_PAGE_SIZE
+ #define CONTEXT_SIZE          VTD_PAGE_SIZE
+ #define IS_BRIDGE_HOST_DEVICE(pdev) \
+                           ((pdev->class >> 8) == PCI_CLASS_BRIDGE_HOST)
+ #define IS_GFX_DEVICE(pdev) ((pdev->class >> 16) == PCI_BASE_CLASS_DISPLAY)
+ #define IS_ISA_DEVICE(pdev) ((pdev->class >> 8) == PCI_CLASS_BRIDGE_ISA)
+ #define IS_AZALIA(pdev) ((pdev)->vendor == 0x8086 && (pdev)->device == 0x3a3e)
+ #define IOAPIC_RANGE_START    (0xfee00000)
+ #define IOAPIC_RANGE_END      (0xfeefffff)
+ #define IOVA_START_ADDR               (0x1000)
+ #define DEFAULT_DOMAIN_ADDRESS_WIDTH 48
+ #define MAX_AGAW_WIDTH 64
+ #define __DOMAIN_MAX_PFN(gaw)  ((((uint64_t)1) << (gaw-VTD_PAGE_SHIFT)) - 1)
+ #define __DOMAIN_MAX_ADDR(gaw) ((((uint64_t)1) << gaw) - 1)
+ /* We limit DOMAIN_MAX_PFN to fit in an unsigned long, and DOMAIN_MAX_ADDR
+    to match. That way, we can use 'unsigned long' for PFNs with impunity. */
+ #define DOMAIN_MAX_PFN(gaw)   ((unsigned long) min_t(uint64_t, \
+                               __DOMAIN_MAX_PFN(gaw), (unsigned long)-1))
+ #define DOMAIN_MAX_ADDR(gaw)  (((uint64_t)__DOMAIN_MAX_PFN(gaw)) << VTD_PAGE_SHIFT)
+ #define IOVA_PFN(addr)                ((addr) >> PAGE_SHIFT)
+ #define DMA_32BIT_PFN         IOVA_PFN(DMA_BIT_MASK(32))
+ #define DMA_64BIT_PFN         IOVA_PFN(DMA_BIT_MASK(64))
+ /* page table handling */
+ #define LEVEL_STRIDE          (9)
+ #define LEVEL_MASK            (((u64)1 << LEVEL_STRIDE) - 1)
+ static inline int agaw_to_level(int agaw)
+ {
+       return agaw + 2;
+ }
+ static inline int agaw_to_width(int agaw)
+ {
+       return 30 + agaw * LEVEL_STRIDE;
+ }
+ static inline int width_to_agaw(int width)
+ {
+       return (width - 30) / LEVEL_STRIDE;
+ }
+ static inline unsigned int level_to_offset_bits(int level)
+ {
+       return (level - 1) * LEVEL_STRIDE;
+ }
+ static inline int pfn_level_offset(unsigned long pfn, int level)
+ {
+       return (pfn >> level_to_offset_bits(level)) & LEVEL_MASK;
+ }
+ static inline unsigned long level_mask(int level)
+ {
+       return -1UL << level_to_offset_bits(level);
+ }
+ static inline unsigned long level_size(int level)
+ {
+       return 1UL << level_to_offset_bits(level);
+ }
+ static inline unsigned long align_to_level(unsigned long pfn, int level)
+ {
+       return (pfn + level_size(level) - 1) & level_mask(level);
+ }
+ static inline unsigned long lvl_to_nr_pages(unsigned int lvl)
+ {
+       return  1 << ((lvl - 1) * LEVEL_STRIDE);
+ }
+ /* VT-d pages must always be _smaller_ than MM pages. Otherwise things
+    are never going to work. */
+ static inline unsigned long dma_to_mm_pfn(unsigned long dma_pfn)
+ {
+       return dma_pfn >> (PAGE_SHIFT - VTD_PAGE_SHIFT);
+ }
+ static inline unsigned long mm_to_dma_pfn(unsigned long mm_pfn)
+ {
+       return mm_pfn << (PAGE_SHIFT - VTD_PAGE_SHIFT);
+ }
+ static inline unsigned long page_to_dma_pfn(struct page *pg)
+ {
+       return mm_to_dma_pfn(page_to_pfn(pg));
+ }
+ static inline unsigned long virt_to_dma_pfn(void *p)
+ {
+       return page_to_dma_pfn(virt_to_page(p));
+ }
+ /* global iommu list, set NULL for ignored DMAR units */
+ static struct intel_iommu **g_iommus;
+ static void __init check_tylersburg_isoch(void);
+ static int rwbf_quirk;
+ /*
+  * set to 1 to panic kernel if can't successfully enable VT-d
+  * (used when kernel is launched w/ TXT)
+  */
+ static int force_on = 0;
+ /*
+  * 0: Present
+  * 1-11: Reserved
+  * 12-63: Context Ptr (12 - (haw-1))
+  * 64-127: Reserved
+  */
+ struct root_entry {
+       u64     val;
+       u64     rsvd1;
+ };
+ #define ROOT_ENTRY_NR (VTD_PAGE_SIZE/sizeof(struct root_entry))
+ static inline bool root_present(struct root_entry *root)
+ {
+       return (root->val & 1);
+ }
+ static inline void set_root_present(struct root_entry *root)
+ {
+       root->val |= 1;
+ }
+ static inline void set_root_value(struct root_entry *root, unsigned long value)
+ {
+       root->val |= value & VTD_PAGE_MASK;
+ }
+ static inline struct context_entry *
+ get_context_addr_from_root(struct root_entry *root)
+ {
+       return (struct context_entry *)
+               (root_present(root)?phys_to_virt(
+               root->val & VTD_PAGE_MASK) :
+               NULL);
+ }
+ /*
+  * low 64 bits:
+  * 0: present
+  * 1: fault processing disable
+  * 2-3: translation type
+  * 12-63: address space root
+  * high 64 bits:
+  * 0-2: address width
+  * 3-6: aval
+  * 8-23: domain id
+  */
+ struct context_entry {
+       u64 lo;
+       u64 hi;
+ };
+ static inline bool context_present(struct context_entry *context)
+ {
+       return (context->lo & 1);
+ }
+ static inline void context_set_present(struct context_entry *context)
+ {
+       context->lo |= 1;
+ }
+ static inline void context_set_fault_enable(struct context_entry *context)
+ {
+       context->lo &= (((u64)-1) << 2) | 1;
+ }
+ static inline void context_set_translation_type(struct context_entry *context,
+                                               unsigned long value)
+ {
+       context->lo &= (((u64)-1) << 4) | 3;
+       context->lo |= (value & 3) << 2;
+ }
+ static inline void context_set_address_root(struct context_entry *context,
+                                           unsigned long value)
+ {
+       context->lo |= value & VTD_PAGE_MASK;
+ }
+ static inline void context_set_address_width(struct context_entry *context,
+                                            unsigned long value)
+ {
+       context->hi |= value & 7;
+ }
+ static inline void context_set_domain_id(struct context_entry *context,
+                                        unsigned long value)
+ {
+       context->hi |= (value & ((1 << 16) - 1)) << 8;
+ }
+ static inline void context_clear_entry(struct context_entry *context)
+ {
+       context->lo = 0;
+       context->hi = 0;
+ }
+ /*
+  * 0: readable
+  * 1: writable
+  * 2-6: reserved
+  * 7: super page
+  * 8-10: available
+  * 11: snoop behavior
+  * 12-63: Host physcial address
+  */
+ struct dma_pte {
+       u64 val;
+ };
+ static inline void dma_clear_pte(struct dma_pte *pte)
+ {
+       pte->val = 0;
+ }
+ static inline void dma_set_pte_readable(struct dma_pte *pte)
+ {
+       pte->val |= DMA_PTE_READ;
+ }
+ static inline void dma_set_pte_writable(struct dma_pte *pte)
+ {
+       pte->val |= DMA_PTE_WRITE;
+ }
+ static inline void dma_set_pte_snp(struct dma_pte *pte)
+ {
+       pte->val |= DMA_PTE_SNP;
+ }
+ static inline void dma_set_pte_prot(struct dma_pte *pte, unsigned long prot)
+ {
+       pte->val = (pte->val & ~3) | (prot & 3);
+ }
+ static inline u64 dma_pte_addr(struct dma_pte *pte)
+ {
+ #ifdef CONFIG_64BIT
+       return pte->val & VTD_PAGE_MASK;
+ #else
+       /* Must have a full atomic 64-bit read */
+       return  __cmpxchg64(&pte->val, 0ULL, 0ULL) & VTD_PAGE_MASK;
+ #endif
+ }
+ static inline void dma_set_pte_pfn(struct dma_pte *pte, unsigned long pfn)
+ {
+       pte->val |= (uint64_t)pfn << VTD_PAGE_SHIFT;
+ }
+ static inline bool dma_pte_present(struct dma_pte *pte)
+ {
+       return (pte->val & 3) != 0;
+ }
+ static inline bool dma_pte_superpage(struct dma_pte *pte)
+ {
+       return (pte->val & (1 << 7));
+ }
+ static inline int first_pte_in_page(struct dma_pte *pte)
+ {
+       return !((unsigned long)pte & ~VTD_PAGE_MASK);
+ }
+ /*
+  * This domain is a statically identity mapping domain.
+  *    1. This domain creats a static 1:1 mapping to all usable memory.
+  *    2. It maps to each iommu if successful.
+  *    3. Each iommu mapps to this domain if successful.
+  */
+ static struct dmar_domain *si_domain;
+ static int hw_pass_through = 1;
+ /* devices under the same p2p bridge are owned in one domain */
+ #define DOMAIN_FLAG_P2P_MULTIPLE_DEVICES (1 << 0)
+ /* domain represents a virtual machine, more than one devices
+  * across iommus may be owned in one domain, e.g. kvm guest.
+  */
+ #define DOMAIN_FLAG_VIRTUAL_MACHINE   (1 << 1)
+ /* si_domain contains mulitple devices */
+ #define DOMAIN_FLAG_STATIC_IDENTITY   (1 << 2)
+ struct dmar_domain {
+       int     id;                     /* domain id */
+       int     nid;                    /* node id */
+       unsigned long iommu_bmp;        /* bitmap of iommus this domain uses*/
+       struct list_head devices;       /* all devices' list */
+       struct iova_domain iovad;       /* iova's that belong to this domain */
+       struct dma_pte  *pgd;           /* virtual address */
+       int             gaw;            /* max guest address width */
+       /* adjusted guest address width, 0 is level 2 30-bit */
+       int             agaw;
+       int             flags;          /* flags to find out type of domain */
+       int             iommu_coherency;/* indicate coherency of iommu access */
+       int             iommu_snooping; /* indicate snooping control feature*/
+       int             iommu_count;    /* reference count of iommu */
+       int             iommu_superpage;/* Level of superpages supported:
+                                          0 == 4KiB (no superpages), 1 == 2MiB,
+                                          2 == 1GiB, 3 == 512GiB, 4 == 1TiB */
+       spinlock_t      iommu_lock;     /* protect iommu set in domain */
+       u64             max_addr;       /* maximum mapped address */
+ };
+ /* PCI domain-device relationship */
+ struct device_domain_info {
+       struct list_head link;  /* link to domain siblings */
+       struct list_head global; /* link to global list */
+       int segment;            /* PCI domain */
+       u8 bus;                 /* PCI bus number */
+       u8 devfn;               /* PCI devfn number */
+       struct pci_dev *dev; /* it's NULL for PCIe-to-PCI bridge */
+       struct intel_iommu *iommu; /* IOMMU used by this device */
+       struct dmar_domain *domain; /* pointer to domain */
+ };
+ static void flush_unmaps_timeout(unsigned long data);
+ DEFINE_TIMER(unmap_timer,  flush_unmaps_timeout, 0, 0);
+ #define HIGH_WATER_MARK 250
+ struct deferred_flush_tables {
+       int next;
+       struct iova *iova[HIGH_WATER_MARK];
+       struct dmar_domain *domain[HIGH_WATER_MARK];
+ };
+ static struct deferred_flush_tables *deferred_flush;
+ /* bitmap for indexing intel_iommus */
+ static int g_num_of_iommus;
+ static DEFINE_SPINLOCK(async_umap_flush_lock);
+ static LIST_HEAD(unmaps_to_do);
+ static int timer_on;
+ static long list_size;
+ static void domain_remove_dev_info(struct dmar_domain *domain);
+ #ifdef CONFIG_INTEL_IOMMU_DEFAULT_ON
+ int dmar_disabled = 0;
+ #else
+ int dmar_disabled = 1;
+ #endif /*CONFIG_INTEL_IOMMU_DEFAULT_ON*/
+ static int dmar_map_gfx = 1;
+ static int dmar_forcedac;
+ static int intel_iommu_strict;
+ static int intel_iommu_superpage = 1;
+ int intel_iommu_gfx_mapped;
+ EXPORT_SYMBOL_GPL(intel_iommu_gfx_mapped);
+ #define DUMMY_DEVICE_DOMAIN_INFO ((struct device_domain_info *)(-1))
+ static DEFINE_SPINLOCK(device_domain_lock);
+ static LIST_HEAD(device_domain_list);
+ static struct iommu_ops intel_iommu_ops;
+ static int __init intel_iommu_setup(char *str)
+ {
+       if (!str)
+               return -EINVAL;
+       while (*str) {
+               if (!strncmp(str, "on", 2)) {
+                       dmar_disabled = 0;
+                       printk(KERN_INFO "Intel-IOMMU: enabled\n");
+               } else if (!strncmp(str, "off", 3)) {
+                       dmar_disabled = 1;
+                       printk(KERN_INFO "Intel-IOMMU: disabled\n");
+               } else if (!strncmp(str, "igfx_off", 8)) {
+                       dmar_map_gfx = 0;
+                       printk(KERN_INFO
+                               "Intel-IOMMU: disable GFX device mapping\n");
+               } else if (!strncmp(str, "forcedac", 8)) {
+                       printk(KERN_INFO
+                               "Intel-IOMMU: Forcing DAC for PCI devices\n");
+                       dmar_forcedac = 1;
+               } else if (!strncmp(str, "strict", 6)) {
+                       printk(KERN_INFO
+                               "Intel-IOMMU: disable batched IOTLB flush\n");
+                       intel_iommu_strict = 1;
+               } else if (!strncmp(str, "sp_off", 6)) {
+                       printk(KERN_INFO
+                               "Intel-IOMMU: disable supported super page\n");
+                       intel_iommu_superpage = 0;
+               }
+               str += strcspn(str, ",");
+               while (*str == ',')
+                       str++;
+       }
+       return 0;
+ }
+ __setup("intel_iommu=", intel_iommu_setup);
+ static struct kmem_cache *iommu_domain_cache;
+ static struct kmem_cache *iommu_devinfo_cache;
+ static struct kmem_cache *iommu_iova_cache;
+ static inline void *alloc_pgtable_page(int node)
+ {
+       struct page *page;
+       void *vaddr = NULL;
+       page = alloc_pages_node(node, GFP_ATOMIC | __GFP_ZERO, 0);
+       if (page)
+               vaddr = page_address(page);
+       return vaddr;
+ }
+ static inline void free_pgtable_page(void *vaddr)
+ {
+       free_page((unsigned long)vaddr);
+ }
+ static inline void *alloc_domain_mem(void)
+ {
+       return kmem_cache_alloc(iommu_domain_cache, GFP_ATOMIC);
+ }
+ static void free_domain_mem(void *vaddr)
+ {
+       kmem_cache_free(iommu_domain_cache, vaddr);
+ }
+ static inline void * alloc_devinfo_mem(void)
+ {
+       return kmem_cache_alloc(iommu_devinfo_cache, GFP_ATOMIC);
+ }
+ static inline void free_devinfo_mem(void *vaddr)
+ {
+       kmem_cache_free(iommu_devinfo_cache, vaddr);
+ }
+ struct iova *alloc_iova_mem(void)
+ {
+       return kmem_cache_alloc(iommu_iova_cache, GFP_ATOMIC);
+ }
+ void free_iova_mem(struct iova *iova)
+ {
+       kmem_cache_free(iommu_iova_cache, iova);
+ }
+ static int __iommu_calculate_agaw(struct intel_iommu *iommu, int max_gaw)
+ {
+       unsigned long sagaw;
+       int agaw = -1;
+       sagaw = cap_sagaw(iommu->cap);
+       for (agaw = width_to_agaw(max_gaw);
+            agaw >= 0; agaw--) {
+               if (test_bit(agaw, &sagaw))
+                       break;
+       }
+       return agaw;
+ }
+ /*
+  * Calculate max SAGAW for each iommu.
+  */
+ int iommu_calculate_max_sagaw(struct intel_iommu *iommu)
+ {
+       return __iommu_calculate_agaw(iommu, MAX_AGAW_WIDTH);
+ }
+ /*
+  * calculate agaw for each iommu.
+  * "SAGAW" may be different across iommus, use a default agaw, and
+  * get a supported less agaw for iommus that don't support the default agaw.
+  */
+ int iommu_calculate_agaw(struct intel_iommu *iommu)
+ {
+       return __iommu_calculate_agaw(iommu, DEFAULT_DOMAIN_ADDRESS_WIDTH);
+ }
+ /* This functionin only returns single iommu in a domain */
+ static struct intel_iommu *domain_get_iommu(struct dmar_domain *domain)
+ {
+       int iommu_id;
+       /* si_domain and vm domain should not get here. */
+       BUG_ON(domain->flags & DOMAIN_FLAG_VIRTUAL_MACHINE);
+       BUG_ON(domain->flags & DOMAIN_FLAG_STATIC_IDENTITY);
+       iommu_id = find_first_bit(&domain->iommu_bmp, g_num_of_iommus);
+       if (iommu_id < 0 || iommu_id >= g_num_of_iommus)
+               return NULL;
+       return g_iommus[iommu_id];
+ }
+ static void domain_update_iommu_coherency(struct dmar_domain *domain)
+ {
+       int i;
+       domain->iommu_coherency = 1;
+       for_each_set_bit(i, &domain->iommu_bmp, g_num_of_iommus) {
+               if (!ecap_coherent(g_iommus[i]->ecap)) {
+                       domain->iommu_coherency = 0;
+                       break;
+               }
+       }
+ }
+ static void domain_update_iommu_snooping(struct dmar_domain *domain)
+ {
+       int i;
+       domain->iommu_snooping = 1;
+       for_each_set_bit(i, &domain->iommu_bmp, g_num_of_iommus) {
+               if (!ecap_sc_support(g_iommus[i]->ecap)) {
+                       domain->iommu_snooping = 0;
+                       break;
+               }
+       }
+ }
+ static void domain_update_iommu_superpage(struct dmar_domain *domain)
+ {
+       struct dmar_drhd_unit *drhd;
+       struct intel_iommu *iommu = NULL;
+       int mask = 0xf;
+       if (!intel_iommu_superpage) {
+               domain->iommu_superpage = 0;
+               return;
+       }
+       /* set iommu_superpage to the smallest common denominator */
+       for_each_active_iommu(iommu, drhd) {
+               mask &= cap_super_page_val(iommu->cap);
+               if (!mask) {
+                       break;
+               }
+       }
+       domain->iommu_superpage = fls(mask);
+ }
+ /* Some capabilities may be different across iommus */
+ static void domain_update_iommu_cap(struct dmar_domain *domain)
+ {
+       domain_update_iommu_coherency(domain);
+       domain_update_iommu_snooping(domain);
+       domain_update_iommu_superpage(domain);
+ }
+ static struct intel_iommu *device_to_iommu(int segment, u8 bus, u8 devfn)
+ {
+       struct dmar_drhd_unit *drhd = NULL;
+       int i;
+       for_each_drhd_unit(drhd) {
+               if (drhd->ignored)
+                       continue;
+               if (segment != drhd->segment)
+                       continue;
+               for (i = 0; i < drhd->devices_cnt; i++) {
+                       if (drhd->devices[i] &&
+                           drhd->devices[i]->bus->number == bus &&
+                           drhd->devices[i]->devfn == devfn)
+                               return drhd->iommu;
+                       if (drhd->devices[i] &&
+                           drhd->devices[i]->subordinate &&
+                           drhd->devices[i]->subordinate->number <= bus &&
+                           drhd->devices[i]->subordinate->subordinate >= bus)
+                               return drhd->iommu;
+               }
+               if (drhd->include_all)
+                       return drhd->iommu;
+       }
+       return NULL;
+ }
+ static void domain_flush_cache(struct dmar_domain *domain,
+                              void *addr, int size)
+ {
+       if (!domain->iommu_coherency)
+               clflush_cache_range(addr, size);
+ }
+ /* Gets context entry for a given bus and devfn */
+ static struct context_entry * device_to_context_entry(struct intel_iommu *iommu,
+               u8 bus, u8 devfn)
+ {
+       struct root_entry *root;
+       struct context_entry *context;
+       unsigned long phy_addr;
+       unsigned long flags;
+       spin_lock_irqsave(&iommu->lock, flags);
+       root = &iommu->root_entry[bus];
+       context = get_context_addr_from_root(root);
+       if (!context) {
+               context = (struct context_entry *)
+                               alloc_pgtable_page(iommu->node);
+               if (!context) {
+                       spin_unlock_irqrestore(&iommu->lock, flags);
+                       return NULL;
+               }
+               __iommu_flush_cache(iommu, (void *)context, CONTEXT_SIZE);
+               phy_addr = virt_to_phys((void *)context);
+               set_root_value(root, phy_addr);
+               set_root_present(root);
+               __iommu_flush_cache(iommu, root, sizeof(*root));
+       }
+       spin_unlock_irqrestore(&iommu->lock, flags);
+       return &context[devfn];
+ }
+ static int device_context_mapped(struct intel_iommu *iommu, u8 bus, u8 devfn)
+ {
+       struct root_entry *root;
+       struct context_entry *context;
+       int ret;
+       unsigned long flags;
+       spin_lock_irqsave(&iommu->lock, flags);
+       root = &iommu->root_entry[bus];
+       context = get_context_addr_from_root(root);
+       if (!context) {
+               ret = 0;
+               goto out;
+       }
+       ret = context_present(&context[devfn]);
+ out:
+       spin_unlock_irqrestore(&iommu->lock, flags);
+       return ret;
+ }
+ static void clear_context_table(struct intel_iommu *iommu, u8 bus, u8 devfn)
+ {
+       struct root_entry *root;
+       struct context_entry *context;
+       unsigned long flags;
+       spin_lock_irqsave(&iommu->lock, flags);
+       root = &iommu->root_entry[bus];
+       context = get_context_addr_from_root(root);
+       if (context) {
+               context_clear_entry(&context[devfn]);
+               __iommu_flush_cache(iommu, &context[devfn], \
+                       sizeof(*context));
+       }
+       spin_unlock_irqrestore(&iommu->lock, flags);
+ }
+ static void free_context_table(struct intel_iommu *iommu)
+ {
+       struct root_entry *root;
+       int i;
+       unsigned long flags;
+       struct context_entry *context;
+       spin_lock_irqsave(&iommu->lock, flags);
+       if (!iommu->root_entry) {
+               goto out;
+       }
+       for (i = 0; i < ROOT_ENTRY_NR; i++) {
+               root = &iommu->root_entry[i];
+               context = get_context_addr_from_root(root);
+               if (context)
+                       free_pgtable_page(context);
+       }
+       free_pgtable_page(iommu->root_entry);
+       iommu->root_entry = NULL;
+ out:
+       spin_unlock_irqrestore(&iommu->lock, flags);
+ }
+ static struct dma_pte *pfn_to_dma_pte(struct dmar_domain *domain,
+                                     unsigned long pfn, int target_level)
+ {
+       int addr_width = agaw_to_width(domain->agaw) - VTD_PAGE_SHIFT;
+       struct dma_pte *parent, *pte = NULL;
+       int level = agaw_to_level(domain->agaw);
+       int offset;
+       BUG_ON(!domain->pgd);
+       BUG_ON(addr_width < BITS_PER_LONG && pfn >> addr_width);
+       parent = domain->pgd;
+       while (level > 0) {
+               void *tmp_page;
+               offset = pfn_level_offset(pfn, level);
+               pte = &parent[offset];
+               if (!target_level && (dma_pte_superpage(pte) || !dma_pte_present(pte)))
+                       break;
+               if (level == target_level)
+                       break;
+               if (!dma_pte_present(pte)) {
+                       uint64_t pteval;
+                       tmp_page = alloc_pgtable_page(domain->nid);
+                       if (!tmp_page)
+                               return NULL;
+                       domain_flush_cache(domain, tmp_page, VTD_PAGE_SIZE);
+                       pteval = ((uint64_t)virt_to_dma_pfn(tmp_page) << VTD_PAGE_SHIFT) | DMA_PTE_READ | DMA_PTE_WRITE;
+                       if (cmpxchg64(&pte->val, 0ULL, pteval)) {
+                               /* Someone else set it while we were thinking; use theirs. */
+                               free_pgtable_page(tmp_page);
+                       } else {
+                               dma_pte_addr(pte);
+                               domain_flush_cache(domain, pte, sizeof(*pte));
+                       }
+               }
+               parent = phys_to_virt(dma_pte_addr(pte));
+               level--;
+       }
+       return pte;
+ }
+ /* return address's pte at specific level */
+ static struct dma_pte *dma_pfn_level_pte(struct dmar_domain *domain,
+                                        unsigned long pfn,
+                                        int level, int *large_page)
+ {
+       struct dma_pte *parent, *pte = NULL;
+       int total = agaw_to_level(domain->agaw);
+       int offset;
+       parent = domain->pgd;
+       while (level <= total) {
+               offset = pfn_level_offset(pfn, total);
+               pte = &parent[offset];
+               if (level == total)
+                       return pte;
+               if (!dma_pte_present(pte)) {
+                       *large_page = total;
+                       break;
+               }
+               if (pte->val & DMA_PTE_LARGE_PAGE) {
+                       *large_page = total;
+                       return pte;
+               }
+               parent = phys_to_virt(dma_pte_addr(pte));
+               total--;
+       }
+       return NULL;
+ }
+ /* clear last level pte, a tlb flush should be followed */
+ static int dma_pte_clear_range(struct dmar_domain *domain,
+                               unsigned long start_pfn,
+                               unsigned long last_pfn)
+ {
+       int addr_width = agaw_to_width(domain->agaw) - VTD_PAGE_SHIFT;
+       unsigned int large_page = 1;
+       struct dma_pte *first_pte, *pte;
+       int order;
+       BUG_ON(addr_width < BITS_PER_LONG && start_pfn >> addr_width);
+       BUG_ON(addr_width < BITS_PER_LONG && last_pfn >> addr_width);
+       BUG_ON(start_pfn > last_pfn);
+       /* we don't need lock here; nobody else touches the iova range */
+       do {
+               large_page = 1;
+               first_pte = pte = dma_pfn_level_pte(domain, start_pfn, 1, &large_page);
+               if (!pte) {
+                       start_pfn = align_to_level(start_pfn + 1, large_page + 1);
+                       continue;
+               }
+               do {
+                       dma_clear_pte(pte);
+                       start_pfn += lvl_to_nr_pages(large_page);
+                       pte++;
+               } while (start_pfn <= last_pfn && !first_pte_in_page(pte));
+               domain_flush_cache(domain, first_pte,
+                                  (void *)pte - (void *)first_pte);
+       } while (start_pfn && start_pfn <= last_pfn);
+       order = (large_page - 1) * 9;
+       return order;
+ }
+ /* free page table pages. last level pte should already be cleared */
+ static void dma_pte_free_pagetable(struct dmar_domain *domain,
+                                  unsigned long start_pfn,
+                                  unsigned long last_pfn)
+ {
+       int addr_width = agaw_to_width(domain->agaw) - VTD_PAGE_SHIFT;
+       struct dma_pte *first_pte, *pte;
+       int total = agaw_to_level(domain->agaw);
+       int level;
+       unsigned long tmp;
+       int large_page = 2;
+       BUG_ON(addr_width < BITS_PER_LONG && start_pfn >> addr_width);
+       BUG_ON(addr_width < BITS_PER_LONG && last_pfn >> addr_width);
+       BUG_ON(start_pfn > last_pfn);
+       /* We don't need lock here; nobody else touches the iova range */
+       level = 2;
+       while (level <= total) {
+               tmp = align_to_level(start_pfn, level);
+               /* If we can't even clear one PTE at this level, we're done */
+               if (tmp + level_size(level) - 1 > last_pfn)
+                       return;
+               do {
+                       large_page = level;
+                       first_pte = pte = dma_pfn_level_pte(domain, tmp, level, &large_page);
+                       if (large_page > level)
+                               level = large_page + 1;
+                       if (!pte) {
+                               tmp = align_to_level(tmp + 1, level + 1);
+                               continue;
+                       }
+                       do {
+                               if (dma_pte_present(pte)) {
+                                       free_pgtable_page(phys_to_virt(dma_pte_addr(pte)));
+                                       dma_clear_pte(pte);
+                               }
+                               pte++;
+                               tmp += level_size(level);
+                       } while (!first_pte_in_page(pte) &&
+                                tmp + level_size(level) - 1 <= last_pfn);
+                       domain_flush_cache(domain, first_pte,
+                                          (void *)pte - (void *)first_pte);
+                       
+               } while (tmp && tmp + level_size(level) - 1 <= last_pfn);
+               level++;
+       }
+       /* free pgd */
+       if (start_pfn == 0 && last_pfn == DOMAIN_MAX_PFN(domain->gaw)) {
+               free_pgtable_page(domain->pgd);
+               domain->pgd = NULL;
+       }
+ }
+ /* iommu handling */
+ static int iommu_alloc_root_entry(struct intel_iommu *iommu)
+ {
+       struct root_entry *root;
+       unsigned long flags;
+       root = (struct root_entry *)alloc_pgtable_page(iommu->node);
+       if (!root)
+               return -ENOMEM;
+       __iommu_flush_cache(iommu, root, ROOT_SIZE);
+       spin_lock_irqsave(&iommu->lock, flags);
+       iommu->root_entry = root;
+       spin_unlock_irqrestore(&iommu->lock, flags);
+       return 0;
+ }
+ static void iommu_set_root_entry(struct intel_iommu *iommu)
+ {
+       void *addr;
+       u32 sts;
+       unsigned long flag;
+       addr = iommu->root_entry;
+       raw_spin_lock_irqsave(&iommu->register_lock, flag);
+       dmar_writeq(iommu->reg + DMAR_RTADDR_REG, virt_to_phys(addr));
+       writel(iommu->gcmd | DMA_GCMD_SRTP, iommu->reg + DMAR_GCMD_REG);
+       /* Make sure hardware complete it */
+       IOMMU_WAIT_OP(iommu, DMAR_GSTS_REG,
+                     readl, (sts & DMA_GSTS_RTPS), sts);
+       raw_spin_unlock_irqrestore(&iommu->register_lock, flag);
+ }
+ static void iommu_flush_write_buffer(struct intel_iommu *iommu)
+ {
+       u32 val;
+       unsigned long flag;
+       if (!rwbf_quirk && !cap_rwbf(iommu->cap))
+               return;
+       raw_spin_lock_irqsave(&iommu->register_lock, flag);
+       writel(iommu->gcmd | DMA_GCMD_WBF, iommu->reg + DMAR_GCMD_REG);
+       /* Make sure hardware complete it */
+       IOMMU_WAIT_OP(iommu, DMAR_GSTS_REG,
+                     readl, (!(val & DMA_GSTS_WBFS)), val);
+       raw_spin_unlock_irqrestore(&iommu->register_lock, flag);
+ }
+ /* return value determine if we need a write buffer flush */
+ static void __iommu_flush_context(struct intel_iommu *iommu,
+                                 u16 did, u16 source_id, u8 function_mask,
+                                 u64 type)
+ {
+       u64 val = 0;
+       unsigned long flag;
+       switch (type) {
+       case DMA_CCMD_GLOBAL_INVL:
+               val = DMA_CCMD_GLOBAL_INVL;
+               break;
+       case DMA_CCMD_DOMAIN_INVL:
+               val = DMA_CCMD_DOMAIN_INVL|DMA_CCMD_DID(did);
+               break;
+       case DMA_CCMD_DEVICE_INVL:
+               val = DMA_CCMD_DEVICE_INVL|DMA_CCMD_DID(did)
+                       | DMA_CCMD_SID(source_id) | DMA_CCMD_FM(function_mask);
+               break;
+       default:
+               BUG();
+       }
+       val |= DMA_CCMD_ICC;
+       raw_spin_lock_irqsave(&iommu->register_lock, flag);
+       dmar_writeq(iommu->reg + DMAR_CCMD_REG, val);
+       /* Make sure hardware complete it */
+       IOMMU_WAIT_OP(iommu, DMAR_CCMD_REG,
+               dmar_readq, (!(val & DMA_CCMD_ICC)), val);
+       raw_spin_unlock_irqrestore(&iommu->register_lock, flag);
+ }
+ /* return value determine if we need a write buffer flush */
+ static void __iommu_flush_iotlb(struct intel_iommu *iommu, u16 did,
+                               u64 addr, unsigned int size_order, u64 type)
+ {
+       int tlb_offset = ecap_iotlb_offset(iommu->ecap);
+       u64 val = 0, val_iva = 0;
+       unsigned long flag;
+       switch (type) {
+       case DMA_TLB_GLOBAL_FLUSH:
+               /* global flush doesn't need set IVA_REG */
+               val = DMA_TLB_GLOBAL_FLUSH|DMA_TLB_IVT;
+               break;
+       case DMA_TLB_DSI_FLUSH:
+               val = DMA_TLB_DSI_FLUSH|DMA_TLB_IVT|DMA_TLB_DID(did);
+               break;
+       case DMA_TLB_PSI_FLUSH:
+               val = DMA_TLB_PSI_FLUSH|DMA_TLB_IVT|DMA_TLB_DID(did);
+               /* Note: always flush non-leaf currently */
+               val_iva = size_order | addr;
+               break;
+       default:
+               BUG();
+       }
+       /* Note: set drain read/write */
+ #if 0
+       /*
+        * This is probably to be super secure.. Looks like we can
+        * ignore it without any impact.
+        */
+       if (cap_read_drain(iommu->cap))
+               val |= DMA_TLB_READ_DRAIN;
+ #endif
+       if (cap_write_drain(iommu->cap))
+               val |= DMA_TLB_WRITE_DRAIN;
+       raw_spin_lock_irqsave(&iommu->register_lock, flag);
+       /* Note: Only uses first TLB reg currently */
+       if (val_iva)
+               dmar_writeq(iommu->reg + tlb_offset, val_iva);
+       dmar_writeq(iommu->reg + tlb_offset + 8, val);
+       /* Make sure hardware complete it */
+       IOMMU_WAIT_OP(iommu, tlb_offset + 8,
+               dmar_readq, (!(val & DMA_TLB_IVT)), val);
+       raw_spin_unlock_irqrestore(&iommu->register_lock, flag);
+       /* check IOTLB invalidation granularity */
+       if (DMA_TLB_IAIG(val) == 0)
+               printk(KERN_ERR"IOMMU: flush IOTLB failed\n");
+       if (DMA_TLB_IAIG(val) != DMA_TLB_IIRG(type))
+               pr_debug("IOMMU: tlb flush request %Lx, actual %Lx\n",
+                       (unsigned long long)DMA_TLB_IIRG(type),
+                       (unsigned long long)DMA_TLB_IAIG(val));
+ }
+ static struct device_domain_info *iommu_support_dev_iotlb(
+       struct dmar_domain *domain, int segment, u8 bus, u8 devfn)
+ {
+       int found = 0;
+       unsigned long flags;
+       struct device_domain_info *info;
+       struct intel_iommu *iommu = device_to_iommu(segment, bus, devfn);
+       if (!ecap_dev_iotlb_support(iommu->ecap))
+               return NULL;
+       if (!iommu->qi)
+               return NULL;
+       spin_lock_irqsave(&device_domain_lock, flags);
+       list_for_each_entry(info, &domain->devices, link)
+               if (info->bus == bus && info->devfn == devfn) {
+                       found = 1;
+                       break;
+               }
+       spin_unlock_irqrestore(&device_domain_lock, flags);
+       if (!found || !info->dev)
+               return NULL;
+       if (!pci_find_ext_capability(info->dev, PCI_EXT_CAP_ID_ATS))
+               return NULL;
+       if (!dmar_find_matched_atsr_unit(info->dev))
+               return NULL;
+       info->iommu = iommu;
+       return info;
+ }
+ static void iommu_enable_dev_iotlb(struct device_domain_info *info)
+ {
+       if (!info)
+               return;
+       pci_enable_ats(info->dev, VTD_PAGE_SHIFT);
+ }
+ static void iommu_disable_dev_iotlb(struct device_domain_info *info)
+ {
+       if (!info->dev || !pci_ats_enabled(info->dev))
+               return;
+       pci_disable_ats(info->dev);
+ }
+ static void iommu_flush_dev_iotlb(struct dmar_domain *domain,
+                                 u64 addr, unsigned mask)
+ {
+       u16 sid, qdep;
+       unsigned long flags;
+       struct device_domain_info *info;
+       spin_lock_irqsave(&device_domain_lock, flags);
+       list_for_each_entry(info, &domain->devices, link) {
+               if (!info->dev || !pci_ats_enabled(info->dev))
+                       continue;
+               sid = info->bus << 8 | info->devfn;
+               qdep = pci_ats_queue_depth(info->dev);
+               qi_flush_dev_iotlb(info->iommu, sid, qdep, addr, mask);
+       }
+       spin_unlock_irqrestore(&device_domain_lock, flags);
+ }
+ static void iommu_flush_iotlb_psi(struct intel_iommu *iommu, u16 did,
+                                 unsigned long pfn, unsigned int pages, int map)
+ {
+       unsigned int mask = ilog2(__roundup_pow_of_two(pages));
+       uint64_t addr = (uint64_t)pfn << VTD_PAGE_SHIFT;
+       BUG_ON(pages == 0);
+       /*
+        * Fallback to domain selective flush if no PSI support or the size is
+        * too big.
+        * PSI requires page size to be 2 ^ x, and the base address is naturally
+        * aligned to the size
+        */
+       if (!cap_pgsel_inv(iommu->cap) || mask > cap_max_amask_val(iommu->cap))
+               iommu->flush.flush_iotlb(iommu, did, 0, 0,
+                                               DMA_TLB_DSI_FLUSH);
+       else
+               iommu->flush.flush_iotlb(iommu, did, addr, mask,
+                                               DMA_TLB_PSI_FLUSH);
+       /*
+        * In caching mode, changes of pages from non-present to present require
+        * flush. However, device IOTLB doesn't need to be flushed in this case.
+        */
+       if (!cap_caching_mode(iommu->cap) || !map)
+               iommu_flush_dev_iotlb(iommu->domains[did], addr, mask);
+ }
+ static void iommu_disable_protect_mem_regions(struct intel_iommu *iommu)
+ {
+       u32 pmen;
+       unsigned long flags;
+       raw_spin_lock_irqsave(&iommu->register_lock, flags);
+       pmen = readl(iommu->reg + DMAR_PMEN_REG);
+       pmen &= ~DMA_PMEN_EPM;
+       writel(pmen, iommu->reg + DMAR_PMEN_REG);
+       /* wait for the protected region status bit to clear */
+       IOMMU_WAIT_OP(iommu, DMAR_PMEN_REG,
+               readl, !(pmen & DMA_PMEN_PRS), pmen);
+       raw_spin_unlock_irqrestore(&iommu->register_lock, flags);
+ }
+ static int iommu_enable_translation(struct intel_iommu *iommu)
+ {
+       u32 sts;
+       unsigned long flags;
+       raw_spin_lock_irqsave(&iommu->register_lock, flags);
+       iommu->gcmd |= DMA_GCMD_TE;
+       writel(iommu->gcmd, iommu->reg + DMAR_GCMD_REG);
+       /* Make sure hardware complete it */
+       IOMMU_WAIT_OP(iommu, DMAR_GSTS_REG,
+                     readl, (sts & DMA_GSTS_TES), sts);
+       raw_spin_unlock_irqrestore(&iommu->register_lock, flags);
+       return 0;
+ }
+ static int iommu_disable_translation(struct intel_iommu *iommu)
+ {
+       u32 sts;
+       unsigned long flag;
+       raw_spin_lock_irqsave(&iommu->register_lock, flag);
+       iommu->gcmd &= ~DMA_GCMD_TE;
+       writel(iommu->gcmd, iommu->reg + DMAR_GCMD_REG);
+       /* Make sure hardware complete it */
+       IOMMU_WAIT_OP(iommu, DMAR_GSTS_REG,
+                     readl, (!(sts & DMA_GSTS_TES)), sts);
+       raw_spin_unlock_irqrestore(&iommu->register_lock, flag);
+       return 0;
+ }
+ static int iommu_init_domains(struct intel_iommu *iommu)
+ {
+       unsigned long ndomains;
+       unsigned long nlongs;
+       ndomains = cap_ndoms(iommu->cap);
+       pr_debug("IOMMU %d: Number of Domains supportd <%ld>\n", iommu->seq_id,
+                       ndomains);
+       nlongs = BITS_TO_LONGS(ndomains);
+       spin_lock_init(&iommu->lock);
+       /* TBD: there might be 64K domains,
+        * consider other allocation for future chip
+        */
+       iommu->domain_ids = kcalloc(nlongs, sizeof(unsigned long), GFP_KERNEL);
+       if (!iommu->domain_ids) {
+               printk(KERN_ERR "Allocating domain id array failed\n");
+               return -ENOMEM;
+       }
+       iommu->domains = kcalloc(ndomains, sizeof(struct dmar_domain *),
+                       GFP_KERNEL);
+       if (!iommu->domains) {
+               printk(KERN_ERR "Allocating domain array failed\n");
+               return -ENOMEM;
+       }
+       /*
+        * if Caching mode is set, then invalid translations are tagged
+        * with domainid 0. Hence we need to pre-allocate it.
+        */
+       if (cap_caching_mode(iommu->cap))
+               set_bit(0, iommu->domain_ids);
+       return 0;
+ }
+ static void domain_exit(struct dmar_domain *domain);
+ static void vm_domain_exit(struct dmar_domain *domain);
+ void free_dmar_iommu(struct intel_iommu *iommu)
+ {
+       struct dmar_domain *domain;
+       int i;
+       unsigned long flags;
+       if ((iommu->domains) && (iommu->domain_ids)) {
+               for_each_set_bit(i, iommu->domain_ids, cap_ndoms(iommu->cap)) {
+                       domain = iommu->domains[i];
+                       clear_bit(i, iommu->domain_ids);
+                       spin_lock_irqsave(&domain->iommu_lock, flags);
+                       if (--domain->iommu_count == 0) {
+                               if (domain->flags & DOMAIN_FLAG_VIRTUAL_MACHINE)
+                                       vm_domain_exit(domain);
+                               else
+                                       domain_exit(domain);
+                       }
+                       spin_unlock_irqrestore(&domain->iommu_lock, flags);
+               }
+       }
+       if (iommu->gcmd & DMA_GCMD_TE)
+               iommu_disable_translation(iommu);
+       if (iommu->irq) {
+               irq_set_handler_data(iommu->irq, NULL);
+               /* This will mask the irq */
+               free_irq(iommu->irq, iommu);
+               destroy_irq(iommu->irq);
+       }
+       kfree(iommu->domains);
+       kfree(iommu->domain_ids);
+       g_iommus[iommu->seq_id] = NULL;
+       /* if all iommus are freed, free g_iommus */
+       for (i = 0; i < g_num_of_iommus; i++) {
+               if (g_iommus[i])
+                       break;
+       }
+       if (i == g_num_of_iommus)
+               kfree(g_iommus);
+       /* free context mapping */
+       free_context_table(iommu);
+ }
+ static struct dmar_domain *alloc_domain(void)
+ {
+       struct dmar_domain *domain;
+       domain = alloc_domain_mem();
+       if (!domain)
+               return NULL;
+       domain->nid = -1;
+       memset(&domain->iommu_bmp, 0, sizeof(unsigned long));
+       domain->flags = 0;
+       return domain;
+ }
+ static int iommu_attach_domain(struct dmar_domain *domain,
+                              struct intel_iommu *iommu)
+ {
+       int num;
+       unsigned long ndomains;
+       unsigned long flags;
+       ndomains = cap_ndoms(iommu->cap);
+       spin_lock_irqsave(&iommu->lock, flags);
+       num = find_first_zero_bit(iommu->domain_ids, ndomains);
+       if (num >= ndomains) {
+               spin_unlock_irqrestore(&iommu->lock, flags);
+               printk(KERN_ERR "IOMMU: no free domain ids\n");
+               return -ENOMEM;
+       }
+       domain->id = num;
+       set_bit(num, iommu->domain_ids);
+       set_bit(iommu->seq_id, &domain->iommu_bmp);
+       iommu->domains[num] = domain;
+       spin_unlock_irqrestore(&iommu->lock, flags);
+       return 0;
+ }
+ static void iommu_detach_domain(struct dmar_domain *domain,
+                               struct intel_iommu *iommu)
+ {
+       unsigned long flags;
+       int num, ndomains;
+       int found = 0;
+       spin_lock_irqsave(&iommu->lock, flags);
+       ndomains = cap_ndoms(iommu->cap);
+       for_each_set_bit(num, iommu->domain_ids, ndomains) {
+               if (iommu->domains[num] == domain) {
+                       found = 1;
+                       break;
+               }
+       }
+       if (found) {
+               clear_bit(num, iommu->domain_ids);
+               clear_bit(iommu->seq_id, &domain->iommu_bmp);
+               iommu->domains[num] = NULL;
+       }
+       spin_unlock_irqrestore(&iommu->lock, flags);
+ }
+ static struct iova_domain reserved_iova_list;
+ static struct lock_class_key reserved_rbtree_key;
+ static int dmar_init_reserved_ranges(void)
+ {
+       struct pci_dev *pdev = NULL;
+       struct iova *iova;
+       int i;
+       init_iova_domain(&reserved_iova_list, DMA_32BIT_PFN);
+       lockdep_set_class(&reserved_iova_list.iova_rbtree_lock,
+               &reserved_rbtree_key);
+       /* IOAPIC ranges shouldn't be accessed by DMA */
+       iova = reserve_iova(&reserved_iova_list, IOVA_PFN(IOAPIC_RANGE_START),
+               IOVA_PFN(IOAPIC_RANGE_END));
+       if (!iova) {
+               printk(KERN_ERR "Reserve IOAPIC range failed\n");
+               return -ENODEV;
+       }
+       /* Reserve all PCI MMIO to avoid peer-to-peer access */
+       for_each_pci_dev(pdev) {
+               struct resource *r;
+               for (i = 0; i < PCI_NUM_RESOURCES; i++) {
+                       r = &pdev->resource[i];
+                       if (!r->flags || !(r->flags & IORESOURCE_MEM))
+                               continue;
+                       iova = reserve_iova(&reserved_iova_list,
+                                           IOVA_PFN(r->start),
+                                           IOVA_PFN(r->end));
+                       if (!iova) {
+                               printk(KERN_ERR "Reserve iova failed\n");
+                               return -ENODEV;
+                       }
+               }
+       }
+       return 0;
+ }
+ static void domain_reserve_special_ranges(struct dmar_domain *domain)
+ {
+       copy_reserved_iova(&reserved_iova_list, &domain->iovad);
+ }
+ static inline int guestwidth_to_adjustwidth(int gaw)
+ {
+       int agaw;
+       int r = (gaw - 12) % 9;
+       if (r == 0)
+               agaw = gaw;
+       else
+               agaw = gaw + 9 - r;
+       if (agaw > 64)
+               agaw = 64;
+       return agaw;
+ }
+ static int domain_init(struct dmar_domain *domain, int guest_width)
+ {
+       struct intel_iommu *iommu;
+       int adjust_width, agaw;
+       unsigned long sagaw;
+       init_iova_domain(&domain->iovad, DMA_32BIT_PFN);
+       spin_lock_init(&domain->iommu_lock);
+       domain_reserve_special_ranges(domain);
+       /* calculate AGAW */
+       iommu = domain_get_iommu(domain);
+       if (guest_width > cap_mgaw(iommu->cap))
+               guest_width = cap_mgaw(iommu->cap);
+       domain->gaw = guest_width;
+       adjust_width = guestwidth_to_adjustwidth(guest_width);
+       agaw = width_to_agaw(adjust_width);
+       sagaw = cap_sagaw(iommu->cap);
+       if (!test_bit(agaw, &sagaw)) {
+               /* hardware doesn't support it, choose a bigger one */
+               pr_debug("IOMMU: hardware doesn't support agaw %d\n", agaw);
+               agaw = find_next_bit(&sagaw, 5, agaw);
+               if (agaw >= 5)
+                       return -ENODEV;
+       }
+       domain->agaw = agaw;
+       INIT_LIST_HEAD(&domain->devices);
+       if (ecap_coherent(iommu->ecap))
+               domain->iommu_coherency = 1;
+       else
+               domain->iommu_coherency = 0;
+       if (ecap_sc_support(iommu->ecap))
+               domain->iommu_snooping = 1;
+       else
+               domain->iommu_snooping = 0;
+       domain->iommu_superpage = fls(cap_super_page_val(iommu->cap));
+       domain->iommu_count = 1;
+       domain->nid = iommu->node;
+       /* always allocate the top pgd */
+       domain->pgd = (struct dma_pte *)alloc_pgtable_page(domain->nid);
+       if (!domain->pgd)
+               return -ENOMEM;
+       __iommu_flush_cache(iommu, domain->pgd, PAGE_SIZE);
+       return 0;
+ }
+ static void domain_exit(struct dmar_domain *domain)
+ {
+       struct dmar_drhd_unit *drhd;
+       struct intel_iommu *iommu;
+       /* Domain 0 is reserved, so dont process it */
+       if (!domain)
+               return;
+       /* Flush any lazy unmaps that may reference this domain */
+       if (!intel_iommu_strict)
+               flush_unmaps_timeout(0);
+       domain_remove_dev_info(domain);
+       /* destroy iovas */
+       put_iova_domain(&domain->iovad);
+       /* clear ptes */
+       dma_pte_clear_range(domain, 0, DOMAIN_MAX_PFN(domain->gaw));
+       /* free page tables */
+       dma_pte_free_pagetable(domain, 0, DOMAIN_MAX_PFN(domain->gaw));
+       for_each_active_iommu(iommu, drhd)
+               if (test_bit(iommu->seq_id, &domain->iommu_bmp))
+                       iommu_detach_domain(domain, iommu);
+       free_domain_mem(domain);
+ }
+ static int domain_context_mapping_one(struct dmar_domain *domain, int segment,
+                                u8 bus, u8 devfn, int translation)
+ {
+       struct context_entry *context;
+       unsigned long flags;
+       struct intel_iommu *iommu;
+       struct dma_pte *pgd;
+       unsigned long num;
+       unsigned long ndomains;
+       int id;
+       int agaw;
+       struct device_domain_info *info = NULL;
+       pr_debug("Set context mapping for %02x:%02x.%d\n",
+               bus, PCI_SLOT(devfn), PCI_FUNC(devfn));
+       BUG_ON(!domain->pgd);
+       BUG_ON(translation != CONTEXT_TT_PASS_THROUGH &&
+              translation != CONTEXT_TT_MULTI_LEVEL);
+       iommu = device_to_iommu(segment, bus, devfn);
+       if (!iommu)
+               return -ENODEV;
+       context = device_to_context_entry(iommu, bus, devfn);
+       if (!context)
+               return -ENOMEM;
+       spin_lock_irqsave(&iommu->lock, flags);
+       if (context_present(context)) {
+               spin_unlock_irqrestore(&iommu->lock, flags);
+               return 0;
+       }
+       id = domain->id;
+       pgd = domain->pgd;
+       if (domain->flags & DOMAIN_FLAG_VIRTUAL_MACHINE ||
+           domain->flags & DOMAIN_FLAG_STATIC_IDENTITY) {
+               int found = 0;
+               /* find an available domain id for this device in iommu */
+               ndomains = cap_ndoms(iommu->cap);
+               for_each_set_bit(num, iommu->domain_ids, ndomains) {
+                       if (iommu->domains[num] == domain) {
+                               id = num;
+                               found = 1;
+                               break;
+                       }
+               }
+               if (found == 0) {
+                       num = find_first_zero_bit(iommu->domain_ids, ndomains);
+                       if (num >= ndomains) {
+                               spin_unlock_irqrestore(&iommu->lock, flags);
+                               printk(KERN_ERR "IOMMU: no free domain ids\n");
+                               return -EFAULT;
+                       }
+                       set_bit(num, iommu->domain_ids);
+                       iommu->domains[num] = domain;
+                       id = num;
+               }
+               /* Skip top levels of page tables for
+                * iommu which has less agaw than default.
+                * Unnecessary for PT mode.
+                */
+               if (translation != CONTEXT_TT_PASS_THROUGH) {
+                       for (agaw = domain->agaw; agaw != iommu->agaw; agaw--) {
+                               pgd = phys_to_virt(dma_pte_addr(pgd));
+                               if (!dma_pte_present(pgd)) {
+                                       spin_unlock_irqrestore(&iommu->lock, flags);
+                                       return -ENOMEM;
+                               }
+                       }
+               }
+       }
+       context_set_domain_id(context, id);
+       if (translation != CONTEXT_TT_PASS_THROUGH) {
+               info = iommu_support_dev_iotlb(domain, segment, bus, devfn);
+               translation = info ? CONTEXT_TT_DEV_IOTLB :
+                                    CONTEXT_TT_MULTI_LEVEL;
+       }
+       /*
+        * In pass through mode, AW must be programmed to indicate the largest
+        * AGAW value supported by hardware. And ASR is ignored by hardware.
+        */
+       if (unlikely(translation == CONTEXT_TT_PASS_THROUGH))
+               context_set_address_width(context, iommu->msagaw);
+       else {
+               context_set_address_root(context, virt_to_phys(pgd));
+               context_set_address_width(context, iommu->agaw);
+       }
+       context_set_translation_type(context, translation);
+       context_set_fault_enable(context);
+       context_set_present(context);
+       domain_flush_cache(domain, context, sizeof(*context));
+       /*
+        * It's a non-present to present mapping. If hardware doesn't cache
+        * non-present entry we only need to flush the write-buffer. If the
+        * _does_ cache non-present entries, then it does so in the special
+        * domain #0, which we have to flush:
+        */
+       if (cap_caching_mode(iommu->cap)) {
+               iommu->flush.flush_context(iommu, 0,
+                                          (((u16)bus) << 8) | devfn,
+                                          DMA_CCMD_MASK_NOBIT,
+                                          DMA_CCMD_DEVICE_INVL);
+               iommu->flush.flush_iotlb(iommu, domain->id, 0, 0, DMA_TLB_DSI_FLUSH);
+       } else {
+               iommu_flush_write_buffer(iommu);
+       }
+       iommu_enable_dev_iotlb(info);
+       spin_unlock_irqrestore(&iommu->lock, flags);
+       spin_lock_irqsave(&domain->iommu_lock, flags);
+       if (!test_and_set_bit(iommu->seq_id, &domain->iommu_bmp)) {
+               domain->iommu_count++;
+               if (domain->iommu_count == 1)
+                       domain->nid = iommu->node;
+               domain_update_iommu_cap(domain);
+       }
+       spin_unlock_irqrestore(&domain->iommu_lock, flags);
+       return 0;
+ }
+ static int
+ domain_context_mapping(struct dmar_domain *domain, struct pci_dev *pdev,
+                       int translation)
+ {
+       int ret;
+       struct pci_dev *tmp, *parent;
+       ret = domain_context_mapping_one(domain, pci_domain_nr(pdev->bus),
+                                        pdev->bus->number, pdev->devfn,
+                                        translation);
+       if (ret)
+               return ret;
+       /* dependent device mapping */
+       tmp = pci_find_upstream_pcie_bridge(pdev);
+       if (!tmp)
+               return 0;
+       /* Secondary interface's bus number and devfn 0 */
+       parent = pdev->bus->self;
+       while (parent != tmp) {
+               ret = domain_context_mapping_one(domain,
+                                                pci_domain_nr(parent->bus),
+                                                parent->bus->number,
+                                                parent->devfn, translation);
+               if (ret)
+                       return ret;
+               parent = parent->bus->self;
+       }
+       if (pci_is_pcie(tmp)) /* this is a PCIe-to-PCI bridge */
+               return domain_context_mapping_one(domain,
+                                       pci_domain_nr(tmp->subordinate),
+                                       tmp->subordinate->number, 0,
+                                       translation);
+       else /* this is a legacy PCI bridge */
+               return domain_context_mapping_one(domain,
+                                                 pci_domain_nr(tmp->bus),
+                                                 tmp->bus->number,
+                                                 tmp->devfn,
+                                                 translation);
+ }
+ static int domain_context_mapped(struct pci_dev *pdev)
+ {
+       int ret;
+       struct pci_dev *tmp, *parent;
+       struct intel_iommu *iommu;
+       iommu = device_to_iommu(pci_domain_nr(pdev->bus), pdev->bus->number,
+                               pdev->devfn);
+       if (!iommu)
+               return -ENODEV;
+       ret = device_context_mapped(iommu, pdev->bus->number, pdev->devfn);
+       if (!ret)
+               return ret;
+       /* dependent device mapping */
+       tmp = pci_find_upstream_pcie_bridge(pdev);
+       if (!tmp)
+               return ret;
+       /* Secondary interface's bus number and devfn 0 */
+       parent = pdev->bus->self;
+       while (parent != tmp) {
+               ret = device_context_mapped(iommu, parent->bus->number,
+                                           parent->devfn);
+               if (!ret)
+                       return ret;
+               parent = parent->bus->self;
+       }
+       if (pci_is_pcie(tmp))
+               return device_context_mapped(iommu, tmp->subordinate->number,
+                                            0);
+       else
+               return device_context_mapped(iommu, tmp->bus->number,
+                                            tmp->devfn);
+ }
+ /* Returns a number of VTD pages, but aligned to MM page size */
+ static inline unsigned long aligned_nrpages(unsigned long host_addr,
+                                           size_t size)
+ {
+       host_addr &= ~PAGE_MASK;
+       return PAGE_ALIGN(host_addr + size) >> VTD_PAGE_SHIFT;
+ }
+ /* Return largest possible superpage level for a given mapping */
+ static inline int hardware_largepage_caps(struct dmar_domain *domain,
+                                         unsigned long iov_pfn,
+                                         unsigned long phy_pfn,
+                                         unsigned long pages)
+ {
+       int support, level = 1;
+       unsigned long pfnmerge;
+       support = domain->iommu_superpage;
+       /* To use a large page, the virtual *and* physical addresses
+          must be aligned to 2MiB/1GiB/etc. Lower bits set in either
+          of them will mean we have to use smaller pages. So just
+          merge them and check both at once. */
+       pfnmerge = iov_pfn | phy_pfn;
+       while (support && !(pfnmerge & ~VTD_STRIDE_MASK)) {
+               pages >>= VTD_STRIDE_SHIFT;
+               if (!pages)
+                       break;
+               pfnmerge >>= VTD_STRIDE_SHIFT;
+               level++;
+               support--;
+       }
+       return level;
+ }
+ static int __domain_mapping(struct dmar_domain *domain, unsigned long iov_pfn,
+                           struct scatterlist *sg, unsigned long phys_pfn,
+                           unsigned long nr_pages, int prot)
+ {
+       struct dma_pte *first_pte = NULL, *pte = NULL;
+       phys_addr_t uninitialized_var(pteval);
+       int addr_width = agaw_to_width(domain->agaw) - VTD_PAGE_SHIFT;
+       unsigned long sg_res;
+       unsigned int largepage_lvl = 0;
+       unsigned long lvl_pages = 0;
+       BUG_ON(addr_width < BITS_PER_LONG && (iov_pfn + nr_pages - 1) >> addr_width);
+       if ((prot & (DMA_PTE_READ|DMA_PTE_WRITE)) == 0)
+               return -EINVAL;
+       prot &= DMA_PTE_READ | DMA_PTE_WRITE | DMA_PTE_SNP;
+       if (sg)
+               sg_res = 0;
+       else {
+               sg_res = nr_pages + 1;
+               pteval = ((phys_addr_t)phys_pfn << VTD_PAGE_SHIFT) | prot;
+       }
+       while (nr_pages > 0) {
+               uint64_t tmp;
+               if (!sg_res) {
+                       sg_res = aligned_nrpages(sg->offset, sg->length);
+                       sg->dma_address = ((dma_addr_t)iov_pfn << VTD_PAGE_SHIFT) + sg->offset;
+                       sg->dma_length = sg->length;
+                       pteval = page_to_phys(sg_page(sg)) | prot;
+                       phys_pfn = pteval >> VTD_PAGE_SHIFT;
+               }
+               if (!pte) {
+                       largepage_lvl = hardware_largepage_caps(domain, iov_pfn, phys_pfn, sg_res);
+                       first_pte = pte = pfn_to_dma_pte(domain, iov_pfn, largepage_lvl);
+                       if (!pte)
+                               return -ENOMEM;
+                       /* It is large page*/
+                       if (largepage_lvl > 1)
+                               pteval |= DMA_PTE_LARGE_PAGE;
+                       else
+                               pteval &= ~(uint64_t)DMA_PTE_LARGE_PAGE;
+               }
+               /* We don't need lock here, nobody else
+                * touches the iova range
+                */
+               tmp = cmpxchg64_local(&pte->val, 0ULL, pteval);
+               if (tmp) {
+                       static int dumps = 5;
+                       printk(KERN_CRIT "ERROR: DMA PTE for vPFN 0x%lx already set (to %llx not %llx)\n",
+                              iov_pfn, tmp, (unsigned long long)pteval);
+                       if (dumps) {
+                               dumps--;
+                               debug_dma_dump_mappings(NULL);
+                       }
+                       WARN_ON(1);
+               }
+               lvl_pages = lvl_to_nr_pages(largepage_lvl);
+               BUG_ON(nr_pages < lvl_pages);
+               BUG_ON(sg_res < lvl_pages);
+               nr_pages -= lvl_pages;
+               iov_pfn += lvl_pages;
+               phys_pfn += lvl_pages;
+               pteval += lvl_pages * VTD_PAGE_SIZE;
+               sg_res -= lvl_pages;
+               /* If the next PTE would be the first in a new page, then we
+                  need to flush the cache on the entries we've just written.
+                  And then we'll need to recalculate 'pte', so clear it and
+                  let it get set again in the if (!pte) block above.
+                  If we're done (!nr_pages) we need to flush the cache too.
+                  Also if we've been setting superpages, we may need to
+                  recalculate 'pte' and switch back to smaller pages for the
+                  end of the mapping, if the trailing size is not enough to
+                  use another superpage (i.e. sg_res < lvl_pages). */
+               pte++;
+               if (!nr_pages || first_pte_in_page(pte) ||
+                   (largepage_lvl > 1 && sg_res < lvl_pages)) {
+                       domain_flush_cache(domain, first_pte,
+                                          (void *)pte - (void *)first_pte);
+                       pte = NULL;
+               }
+               if (!sg_res && nr_pages)
+                       sg = sg_next(sg);
+       }
+       return 0;
+ }
+ static inline int domain_sg_mapping(struct dmar_domain *domain, unsigned long iov_pfn,
+                                   struct scatterlist *sg, unsigned long nr_pages,
+                                   int prot)
+ {
+       return __domain_mapping(domain, iov_pfn, sg, 0, nr_pages, prot);
+ }
+ static inline int domain_pfn_mapping(struct dmar_domain *domain, unsigned long iov_pfn,
+                                    unsigned long phys_pfn, unsigned long nr_pages,
+                                    int prot)
+ {
+       return __domain_mapping(domain, iov_pfn, NULL, phys_pfn, nr_pages, prot);
+ }
+ static void iommu_detach_dev(struct intel_iommu *iommu, u8 bus, u8 devfn)
+ {
+       if (!iommu)
+               return;
+       clear_context_table(iommu, bus, devfn);
+       iommu->flush.flush_context(iommu, 0, 0, 0,
+                                          DMA_CCMD_GLOBAL_INVL);
+       iommu->flush.flush_iotlb(iommu, 0, 0, 0, DMA_TLB_GLOBAL_FLUSH);
+ }
+ static void domain_remove_dev_info(struct dmar_domain *domain)
+ {
+       struct device_domain_info *info;
+       unsigned long flags;
+       struct intel_iommu *iommu;
+       spin_lock_irqsave(&device_domain_lock, flags);
+       while (!list_empty(&domain->devices)) {
+               info = list_entry(domain->devices.next,
+                       struct device_domain_info, link);
+               list_del(&info->link);
+               list_del(&info->global);
+               if (info->dev)
+                       info->dev->dev.archdata.iommu = NULL;
+               spin_unlock_irqrestore(&device_domain_lock, flags);
+               iommu_disable_dev_iotlb(info);
+               iommu = device_to_iommu(info->segment, info->bus, info->devfn);
+               iommu_detach_dev(iommu, info->bus, info->devfn);
+               free_devinfo_mem(info);
+               spin_lock_irqsave(&device_domain_lock, flags);
+       }
+       spin_unlock_irqrestore(&device_domain_lock, flags);
+ }
+ /*
+  * find_domain
+  * Note: we use struct pci_dev->dev.archdata.iommu stores the info
+  */
+ static struct dmar_domain *
+ find_domain(struct pci_dev *pdev)
+ {
+       struct device_domain_info *info;
+       /* No lock here, assumes no domain exit in normal case */
+       info = pdev->dev.archdata.iommu;
+       if (info)
+               return info->domain;
+       return NULL;
+ }
+ /* domain is initialized */
+ static struct dmar_domain *get_domain_for_dev(struct pci_dev *pdev, int gaw)
+ {
+       struct dmar_domain *domain, *found = NULL;
+       struct intel_iommu *iommu;
+       struct dmar_drhd_unit *drhd;
+       struct device_domain_info *info, *tmp;
+       struct pci_dev *dev_tmp;
+       unsigned long flags;
+       int bus = 0, devfn = 0;
+       int segment;
+       int ret;
+       domain = find_domain(pdev);
+       if (domain)
+               return domain;
+       segment = pci_domain_nr(pdev->bus);
+       dev_tmp = pci_find_upstream_pcie_bridge(pdev);
+       if (dev_tmp) {
+               if (pci_is_pcie(dev_tmp)) {
+                       bus = dev_tmp->subordinate->number;
+                       devfn = 0;
+               } else {
+                       bus = dev_tmp->bus->number;
+                       devfn = dev_tmp->devfn;
+               }
+               spin_lock_irqsave(&device_domain_lock, flags);
+               list_for_each_entry(info, &device_domain_list, global) {
+                       if (info->segment == segment &&
+                           info->bus == bus && info->devfn == devfn) {
+                               found = info->domain;
+                               break;
+                       }
+               }
+               spin_unlock_irqrestore(&device_domain_lock, flags);
+               /* pcie-pci bridge already has a domain, uses it */
+               if (found) {
+                       domain = found;
+                       goto found_domain;
+               }
+       }
+       domain = alloc_domain();
+       if (!domain)
+               goto error;
+       /* Allocate new domain for the device */
+       drhd = dmar_find_matched_drhd_unit(pdev);
+       if (!drhd) {
+               printk(KERN_ERR "IOMMU: can't find DMAR for device %s\n",
+                       pci_name(pdev));
+               return NULL;
+       }
+       iommu = drhd->iommu;
+       ret = iommu_attach_domain(domain, iommu);
+       if (ret) {
+               free_domain_mem(domain);
+               goto error;
+       }
+       if (domain_init(domain, gaw)) {
+               domain_exit(domain);
+               goto error;
+       }
+       /* register pcie-to-pci device */
+       if (dev_tmp) {
+               info = alloc_devinfo_mem();
+               if (!info) {
+                       domain_exit(domain);
+                       goto error;
+               }
+               info->segment = segment;
+               info->bus = bus;
+               info->devfn = devfn;
+               info->dev = NULL;
+               info->domain = domain;
+               /* This domain is shared by devices under p2p bridge */
+               domain->flags |= DOMAIN_FLAG_P2P_MULTIPLE_DEVICES;
+               /* pcie-to-pci bridge already has a domain, uses it */
+               found = NULL;
+               spin_lock_irqsave(&device_domain_lock, flags);
+               list_for_each_entry(tmp, &device_domain_list, global) {
+                       if (tmp->segment == segment &&
+                           tmp->bus == bus && tmp->devfn == devfn) {
+                               found = tmp->domain;
+                               break;
+                       }
+               }
+               if (found) {
+                       spin_unlock_irqrestore(&device_domain_lock, flags);
+                       free_devinfo_mem(info);
+                       domain_exit(domain);
+                       domain = found;
+               } else {
+                       list_add(&info->link, &domain->devices);
+                       list_add(&info->global, &device_domain_list);
+                       spin_unlock_irqrestore(&device_domain_lock, flags);
+               }
+       }
+ found_domain:
+       info = alloc_devinfo_mem();
+       if (!info)
+               goto error;
+       info->segment = segment;
+       info->bus = pdev->bus->number;
+       info->devfn = pdev->devfn;
+       info->dev = pdev;
+       info->domain = domain;
+       spin_lock_irqsave(&device_domain_lock, flags);
+       /* somebody is fast */
+       found = find_domain(pdev);
+       if (found != NULL) {
+               spin_unlock_irqrestore(&device_domain_lock, flags);
+               if (found != domain) {
+                       domain_exit(domain);
+                       domain = found;
+               }
+               free_devinfo_mem(info);
+               return domain;
+       }
+       list_add(&info->link, &domain->devices);
+       list_add(&info->global, &device_domain_list);
+       pdev->dev.archdata.iommu = info;
+       spin_unlock_irqrestore(&device_domain_lock, flags);
+       return domain;
+ error:
+       /* recheck it here, maybe others set it */
+       return find_domain(pdev);
+ }
+ static int iommu_identity_mapping;
+ #define IDENTMAP_ALL          1
+ #define IDENTMAP_GFX          2
+ #define IDENTMAP_AZALIA               4
+ static int iommu_domain_identity_map(struct dmar_domain *domain,
+                                    unsigned long long start,
+                                    unsigned long long end)
+ {
+       unsigned long first_vpfn = start >> VTD_PAGE_SHIFT;
+       unsigned long last_vpfn = end >> VTD_PAGE_SHIFT;
+       if (!reserve_iova(&domain->iovad, dma_to_mm_pfn(first_vpfn),
+                         dma_to_mm_pfn(last_vpfn))) {
+               printk(KERN_ERR "IOMMU: reserve iova failed\n");
+               return -ENOMEM;
+       }
+       pr_debug("Mapping reserved region %llx-%llx for domain %d\n",
+                start, end, domain->id);
+       /*
+        * RMRR range might have overlap with physical memory range,
+        * clear it first
+        */
+       dma_pte_clear_range(domain, first_vpfn, last_vpfn);
+       return domain_pfn_mapping(domain, first_vpfn, first_vpfn,
+                                 last_vpfn - first_vpfn + 1,
+                                 DMA_PTE_READ|DMA_PTE_WRITE);
+ }
+ static int iommu_prepare_identity_map(struct pci_dev *pdev,
+                                     unsigned long long start,
+                                     unsigned long long end)
+ {
+       struct dmar_domain *domain;
+       int ret;
+       domain = get_domain_for_dev(pdev, DEFAULT_DOMAIN_ADDRESS_WIDTH);
+       if (!domain)
+               return -ENOMEM;
+       /* For _hardware_ passthrough, don't bother. But for software
+          passthrough, we do it anyway -- it may indicate a memory
+          range which is reserved in E820, so which didn't get set
+          up to start with in si_domain */
+       if (domain == si_domain && hw_pass_through) {
+               printk("Ignoring identity map for HW passthrough device %s [0x%Lx - 0x%Lx]\n",
+                      pci_name(pdev), start, end);
+               return 0;
+       }
+       printk(KERN_INFO
+              "IOMMU: Setting identity map for device %s [0x%Lx - 0x%Lx]\n",
+              pci_name(pdev), start, end);
+       
+       if (end < start) {
+               WARN(1, "Your BIOS is broken; RMRR ends before it starts!\n"
+                       "BIOS vendor: %s; Ver: %s; Product Version: %s\n",
+                       dmi_get_system_info(DMI_BIOS_VENDOR),
+                       dmi_get_system_info(DMI_BIOS_VERSION),
+                    dmi_get_system_info(DMI_PRODUCT_VERSION));
+               ret = -EIO;
+               goto error;
+       }
+       if (end >> agaw_to_width(domain->agaw)) {
+               WARN(1, "Your BIOS is broken; RMRR exceeds permitted address width (%d bits)\n"
+                    "BIOS vendor: %s; Ver: %s; Product Version: %s\n",
+                    agaw_to_width(domain->agaw),
+                    dmi_get_system_info(DMI_BIOS_VENDOR),
+                    dmi_get_system_info(DMI_BIOS_VERSION),
+                    dmi_get_system_info(DMI_PRODUCT_VERSION));
+               ret = -EIO;
+               goto error;
+       }
+       ret = iommu_domain_identity_map(domain, start, end);
+       if (ret)
+               goto error;
+       /* context entry init */
+       ret = domain_context_mapping(domain, pdev, CONTEXT_TT_MULTI_LEVEL);
+       if (ret)
+               goto error;
+       return 0;
+  error:
+       domain_exit(domain);
+       return ret;
+ }
+ static inline int iommu_prepare_rmrr_dev(struct dmar_rmrr_unit *rmrr,
+       struct pci_dev *pdev)
+ {
+       if (pdev->dev.archdata.iommu == DUMMY_DEVICE_DOMAIN_INFO)
+               return 0;
+       return iommu_prepare_identity_map(pdev, rmrr->base_address,
+               rmrr->end_address);
+ }
+ #ifdef CONFIG_INTEL_IOMMU_FLOPPY_WA
+ static inline void iommu_prepare_isa(void)
+ {
+       struct pci_dev *pdev;
+       int ret;
+       pdev = pci_get_class(PCI_CLASS_BRIDGE_ISA << 8, NULL);
+       if (!pdev)
+               return;
+       printk(KERN_INFO "IOMMU: Prepare 0-16MiB unity mapping for LPC\n");
+       ret = iommu_prepare_identity_map(pdev, 0, 16*1024*1024 - 1);
+       if (ret)
+               printk(KERN_ERR "IOMMU: Failed to create 0-16MiB identity map; "
+                      "floppy might not work\n");
+ }
+ #else
+ static inline void iommu_prepare_isa(void)
+ {
+       return;
+ }
+ #endif /* !CONFIG_INTEL_IOMMU_FLPY_WA */
+ static int md_domain_init(struct dmar_domain *domain, int guest_width);
 -              work_with_active_regions(nid, si_domain_work_fn, &ret);
 -              if (ret)
 -                      return ret;
+ static int __init si_domain_init(int hw)
+ {
+       struct dmar_drhd_unit *drhd;
+       struct intel_iommu *iommu;
+       int nid, ret = 0;
+       si_domain = alloc_domain();
+       if (!si_domain)
+               return -EFAULT;
+       pr_debug("Identity mapping domain is domain %d\n", si_domain->id);
+       for_each_active_iommu(iommu, drhd) {
+               ret = iommu_attach_domain(si_domain, iommu);
+               if (ret) {
+                       domain_exit(si_domain);
+                       return -EFAULT;
+               }
+       }
+       if (md_domain_init(si_domain, DEFAULT_DOMAIN_ADDRESS_WIDTH)) {
+               domain_exit(si_domain);
+               return -EFAULT;
+       }
+       si_domain->flags = DOMAIN_FLAG_STATIC_IDENTITY;
+       if (hw)
+               return 0;
+       for_each_online_node(nid) {
++              unsigned long start_pfn, end_pfn;
++              int i;
++
++              for_each_mem_pfn_range(i, nid, &start_pfn, &end_pfn, NULL) {
++                      ret = iommu_domain_identity_map(si_domain,
++                                      PFN_PHYS(start_pfn), PFN_PHYS(end_pfn));
++                      if (ret)
++                              return ret;
++              }
+       }
+       return 0;
+ }
+ static void domain_remove_one_dev_info(struct dmar_domain *domain,
+                                         struct pci_dev *pdev);
+ static int identity_mapping(struct pci_dev *pdev)
+ {
+       struct device_domain_info *info;
+       if (likely(!iommu_identity_mapping))
+               return 0;
+       info = pdev->dev.archdata.iommu;
+       if (info && info != DUMMY_DEVICE_DOMAIN_INFO)
+               return (info->domain == si_domain);
+       return 0;
+ }
+ static int domain_add_dev_info(struct dmar_domain *domain,
+                              struct pci_dev *pdev,
+                              int translation)
+ {
+       struct device_domain_info *info;
+       unsigned long flags;
+       int ret;
+       info = alloc_devinfo_mem();
+       if (!info)
+               return -ENOMEM;
+       ret = domain_context_mapping(domain, pdev, translation);
+       if (ret) {
+               free_devinfo_mem(info);
+               return ret;
+       }
+       info->segment = pci_domain_nr(pdev->bus);
+       info->bus = pdev->bus->number;
+       info->devfn = pdev->devfn;
+       info->dev = pdev;
+       info->domain = domain;
+       spin_lock_irqsave(&device_domain_lock, flags);
+       list_add(&info->link, &domain->devices);
+       list_add(&info->global, &device_domain_list);
+       pdev->dev.archdata.iommu = info;
+       spin_unlock_irqrestore(&device_domain_lock, flags);
+       return 0;
+ }
+ static int iommu_should_identity_map(struct pci_dev *pdev, int startup)
+ {
+       if ((iommu_identity_mapping & IDENTMAP_AZALIA) && IS_AZALIA(pdev))
+               return 1;
+       if ((iommu_identity_mapping & IDENTMAP_GFX) && IS_GFX_DEVICE(pdev))
+               return 1;
+       if (!(iommu_identity_mapping & IDENTMAP_ALL))
+               return 0;
+       /*
+        * We want to start off with all devices in the 1:1 domain, and
+        * take them out later if we find they can't access all of memory.
+        *
+        * However, we can't do this for PCI devices behind bridges,
+        * because all PCI devices behind the same bridge will end up
+        * with the same source-id on their transactions.
+        *
+        * Practically speaking, we can't change things around for these
+        * devices at run-time, because we can't be sure there'll be no
+        * DMA transactions in flight for any of their siblings.
+        * 
+        * So PCI devices (unless they're on the root bus) as well as
+        * their parent PCI-PCI or PCIe-PCI bridges must be left _out_ of
+        * the 1:1 domain, just in _case_ one of their siblings turns out
+        * not to be able to map all of memory.
+        */
+       if (!pci_is_pcie(pdev)) {
+               if (!pci_is_root_bus(pdev->bus))
+                       return 0;
+               if (pdev->class >> 8 == PCI_CLASS_BRIDGE_PCI)
+                       return 0;
+       } else if (pdev->pcie_type == PCI_EXP_TYPE_PCI_BRIDGE)
+               return 0;
+       /* 
+        * At boot time, we don't yet know if devices will be 64-bit capable.
+        * Assume that they will -- if they turn out not to be, then we can 
+        * take them out of the 1:1 domain later.
+        */
+       if (!startup) {
+               /*
+                * If the device's dma_mask is less than the system's memory
+                * size then this is not a candidate for identity mapping.
+                */
+               u64 dma_mask = pdev->dma_mask;
+               if (pdev->dev.coherent_dma_mask &&
+                   pdev->dev.coherent_dma_mask < dma_mask)
+                       dma_mask = pdev->dev.coherent_dma_mask;
+               return dma_mask >= dma_get_required_mask(&pdev->dev);
+       }
+       return 1;
+ }
+ static int __init iommu_prepare_static_identity_mapping(int hw)
+ {
+       struct pci_dev *pdev = NULL;
+       int ret;
+       ret = si_domain_init(hw);
+       if (ret)
+               return -EFAULT;
+       for_each_pci_dev(pdev) {
+               /* Skip Host/PCI Bridge devices */
+               if (IS_BRIDGE_HOST_DEVICE(pdev))
+                       continue;
+               if (iommu_should_identity_map(pdev, 1)) {
+                       printk(KERN_INFO "IOMMU: %s identity mapping for device %s\n",
+                              hw ? "hardware" : "software", pci_name(pdev));
+                       ret = domain_add_dev_info(si_domain, pdev,
+                                                    hw ? CONTEXT_TT_PASS_THROUGH :
+                                                    CONTEXT_TT_MULTI_LEVEL);
+                       if (ret)
+                               return ret;
+               }
+       }
+       return 0;
+ }
+ static int __init init_dmars(void)
+ {
+       struct dmar_drhd_unit *drhd;
+       struct dmar_rmrr_unit *rmrr;
+       struct pci_dev *pdev;
+       struct intel_iommu *iommu;
+       int i, ret;
+       /*
+        * for each drhd
+        *    allocate root
+        *    initialize and program root entry to not present
+        * endfor
+        */
+       for_each_drhd_unit(drhd) {
+               g_num_of_iommus++;
+               /*
+                * lock not needed as this is only incremented in the single
+                * threaded kernel __init code path all other access are read
+                * only
+                */
+       }
+       g_iommus = kcalloc(g_num_of_iommus, sizeof(struct intel_iommu *),
+                       GFP_KERNEL);
+       if (!g_iommus) {
+               printk(KERN_ERR "Allocating global iommu array failed\n");
+               ret = -ENOMEM;
+               goto error;
+       }
+       deferred_flush = kzalloc(g_num_of_iommus *
+               sizeof(struct deferred_flush_tables), GFP_KERNEL);
+       if (!deferred_flush) {
+               ret = -ENOMEM;
+               goto error;
+       }
+       for_each_drhd_unit(drhd) {
+               if (drhd->ignored)
+                       continue;
+               iommu = drhd->iommu;
+               g_iommus[iommu->seq_id] = iommu;
+               ret = iommu_init_domains(iommu);
+               if (ret)
+                       goto error;
+               /*
+                * TBD:
+                * we could share the same root & context tables
+                * among all IOMMU's. Need to Split it later.
+                */
+               ret = iommu_alloc_root_entry(iommu);
+               if (ret) {
+                       printk(KERN_ERR "IOMMU: allocate root entry failed\n");
+                       goto error;
+               }
+               if (!ecap_pass_through(iommu->ecap))
+                       hw_pass_through = 0;
+       }
+       /*
+        * Start from the sane iommu hardware state.
+        */
+       for_each_drhd_unit(drhd) {
+               if (drhd->ignored)
+                       continue;
+               iommu = drhd->iommu;
+               /*
+                * If the queued invalidation is already initialized by us
+                * (for example, while enabling interrupt-remapping) then
+                * we got the things already rolling from a sane state.
+                */
+               if (iommu->qi)
+                       continue;
+               /*
+                * Clear any previous faults.
+                */
+               dmar_fault(-1, iommu);
+               /*
+                * Disable queued invalidation if supported and already enabled
+                * before OS handover.
+                */
+               dmar_disable_qi(iommu);
+       }
+       for_each_drhd_unit(drhd) {
+               if (drhd->ignored)
+                       continue;
+               iommu = drhd->iommu;
+               if (dmar_enable_qi(iommu)) {
+                       /*
+                        * Queued Invalidate not enabled, use Register Based
+                        * Invalidate
+                        */
+                       iommu->flush.flush_context = __iommu_flush_context;
+                       iommu->flush.flush_iotlb = __iommu_flush_iotlb;
+                       printk(KERN_INFO "IOMMU %d 0x%Lx: using Register based "
+                              "invalidation\n",
+                               iommu->seq_id,
+                              (unsigned long long)drhd->reg_base_addr);
+               } else {
+                       iommu->flush.flush_context = qi_flush_context;
+                       iommu->flush.flush_iotlb = qi_flush_iotlb;
+                       printk(KERN_INFO "IOMMU %d 0x%Lx: using Queued "
+                              "invalidation\n",
+                               iommu->seq_id,
+                              (unsigned long long)drhd->reg_base_addr);
+               }
+       }
+       if (iommu_pass_through)
+               iommu_identity_mapping |= IDENTMAP_ALL;
+ #ifdef CONFIG_INTEL_IOMMU_BROKEN_GFX_WA
+       iommu_identity_mapping |= IDENTMAP_GFX;
+ #endif
+       check_tylersburg_isoch();
+       /*
+        * If pass through is not set or not enabled, setup context entries for
+        * identity mappings for rmrr, gfx, and isa and may fall back to static
+        * identity mapping if iommu_identity_mapping is set.
+        */
+       if (iommu_identity_mapping) {
+               ret = iommu_prepare_static_identity_mapping(hw_pass_through);
+               if (ret) {
+                       printk(KERN_CRIT "Failed to setup IOMMU pass-through\n");
+                       goto error;
+               }
+       }
+       /*
+        * For each rmrr
+        *   for each dev attached to rmrr
+        *   do
+        *     locate drhd for dev, alloc domain for dev
+        *     allocate free domain
+        *     allocate page table entries for rmrr
+        *     if context not allocated for bus
+        *           allocate and init context
+        *           set present in root table for this bus
+        *     init context with domain, translation etc
+        *    endfor
+        * endfor
+        */
+       printk(KERN_INFO "IOMMU: Setting RMRR:\n");
+       for_each_rmrr_units(rmrr) {
+               for (i = 0; i < rmrr->devices_cnt; i++) {
+                       pdev = rmrr->devices[i];
+                       /*
+                        * some BIOS lists non-exist devices in DMAR
+                        * table.
+                        */
+                       if (!pdev)
+                               continue;
+                       ret = iommu_prepare_rmrr_dev(rmrr, pdev);
+                       if (ret)
+                               printk(KERN_ERR
+                                      "IOMMU: mapping reserved region failed\n");
+               }
+       }
+       iommu_prepare_isa();
+       /*
+        * for each drhd
+        *   enable fault log
+        *   global invalidate context cache
+        *   global invalidate iotlb
+        *   enable translation
+        */
+       for_each_drhd_unit(drhd) {
+               if (drhd->ignored) {
+                       /*
+                        * we always have to disable PMRs or DMA may fail on
+                        * this device
+                        */
+                       if (force_on)
+                               iommu_disable_protect_mem_regions(drhd->iommu);
+                       continue;
+               }
+               iommu = drhd->iommu;
+               iommu_flush_write_buffer(iommu);
+               ret = dmar_set_interrupt(iommu);
+               if (ret)
+                       goto error;
+               iommu_set_root_entry(iommu);
+               iommu->flush.flush_context(iommu, 0, 0, 0, DMA_CCMD_GLOBAL_INVL);
+               iommu->flush.flush_iotlb(iommu, 0, 0, 0, DMA_TLB_GLOBAL_FLUSH);
+               ret = iommu_enable_translation(iommu);
+               if (ret)
+                       goto error;
+               iommu_disable_protect_mem_regions(iommu);
+       }
+       return 0;
+ error:
+       for_each_drhd_unit(drhd) {
+               if (drhd->ignored)
+                       continue;
+               iommu = drhd->iommu;
+               free_iommu(iommu);
+       }
+       kfree(g_iommus);
+       return ret;
+ }
+ /* This takes a number of _MM_ pages, not VTD pages */
+ static struct iova *intel_alloc_iova(struct device *dev,
+                                    struct dmar_domain *domain,
+                                    unsigned long nrpages, uint64_t dma_mask)
+ {
+       struct pci_dev *pdev = to_pci_dev(dev);
+       struct iova *iova = NULL;
+       /* Restrict dma_mask to the width that the iommu can handle */
+       dma_mask = min_t(uint64_t, DOMAIN_MAX_ADDR(domain->gaw), dma_mask);
+       if (!dmar_forcedac && dma_mask > DMA_BIT_MASK(32)) {
+               /*
+                * First try to allocate an io virtual address in
+                * DMA_BIT_MASK(32) and if that fails then try allocating
+                * from higher range
+                */
+               iova = alloc_iova(&domain->iovad, nrpages,
+                                 IOVA_PFN(DMA_BIT_MASK(32)), 1);
+               if (iova)
+                       return iova;
+       }
+       iova = alloc_iova(&domain->iovad, nrpages, IOVA_PFN(dma_mask), 1);
+       if (unlikely(!iova)) {
+               printk(KERN_ERR "Allocating %ld-page iova for %s failed",
+                      nrpages, pci_name(pdev));
+               return NULL;
+       }
+       return iova;
+ }
+ static struct dmar_domain *__get_valid_domain_for_dev(struct pci_dev *pdev)
+ {
+       struct dmar_domain *domain;
+       int ret;
+       domain = get_domain_for_dev(pdev,
+                       DEFAULT_DOMAIN_ADDRESS_WIDTH);
+       if (!domain) {
+               printk(KERN_ERR
+                       "Allocating domain for %s failed", pci_name(pdev));
+               return NULL;
+       }
+       /* make sure context mapping is ok */
+       if (unlikely(!domain_context_mapped(pdev))) {
+               ret = domain_context_mapping(domain, pdev,
+                                            CONTEXT_TT_MULTI_LEVEL);
+               if (ret) {
+                       printk(KERN_ERR
+                               "Domain context map for %s failed",
+                               pci_name(pdev));
+                       return NULL;
+               }
+       }
+       return domain;
+ }
+ static inline struct dmar_domain *get_valid_domain_for_dev(struct pci_dev *dev)
+ {
+       struct device_domain_info *info;
+       /* No lock here, assumes no domain exit in normal case */
+       info = dev->dev.archdata.iommu;
+       if (likely(info))
+               return info->domain;
+       return __get_valid_domain_for_dev(dev);
+ }
+ static int iommu_dummy(struct pci_dev *pdev)
+ {
+       return pdev->dev.archdata.iommu == DUMMY_DEVICE_DOMAIN_INFO;
+ }
+ /* Check if the pdev needs to go through non-identity map and unmap process.*/
+ static int iommu_no_mapping(struct device *dev)
+ {
+       struct pci_dev *pdev;
+       int found;
+       if (unlikely(dev->bus != &pci_bus_type))
+               return 1;
+       pdev = to_pci_dev(dev);
+       if (iommu_dummy(pdev))
+               return 1;
+       if (!iommu_identity_mapping)
+               return 0;
+       found = identity_mapping(pdev);
+       if (found) {
+               if (iommu_should_identity_map(pdev, 0))
+                       return 1;
+               else {
+                       /*
+                        * 32 bit DMA is removed from si_domain and fall back
+                        * to non-identity mapping.
+                        */
+                       domain_remove_one_dev_info(si_domain, pdev);
+                       printk(KERN_INFO "32bit %s uses non-identity mapping\n",
+                              pci_name(pdev));
+                       return 0;
+               }
+       } else {
+               /*
+                * In case of a detached 64 bit DMA device from vm, the device
+                * is put into si_domain for identity mapping.
+                */
+               if (iommu_should_identity_map(pdev, 0)) {
+                       int ret;
+                       ret = domain_add_dev_info(si_domain, pdev,
+                                                 hw_pass_through ?
+                                                 CONTEXT_TT_PASS_THROUGH :
+                                                 CONTEXT_TT_MULTI_LEVEL);
+                       if (!ret) {
+                               printk(KERN_INFO "64bit %s uses identity mapping\n",
+                                      pci_name(pdev));
+                               return 1;
+                       }
+               }
+       }
+       return 0;
+ }
+ static dma_addr_t __intel_map_single(struct device *hwdev, phys_addr_t paddr,
+                                    size_t size, int dir, u64 dma_mask)
+ {
+       struct pci_dev *pdev = to_pci_dev(hwdev);
+       struct dmar_domain *domain;
+       phys_addr_t start_paddr;
+       struct iova *iova;
+       int prot = 0;
+       int ret;
+       struct intel_iommu *iommu;
+       unsigned long paddr_pfn = paddr >> PAGE_SHIFT;
+       BUG_ON(dir == DMA_NONE);
+       if (iommu_no_mapping(hwdev))
+               return paddr;
+       domain = get_valid_domain_for_dev(pdev);
+       if (!domain)
+               return 0;
+       iommu = domain_get_iommu(domain);
+       size = aligned_nrpages(paddr, size);
+       iova = intel_alloc_iova(hwdev, domain, dma_to_mm_pfn(size), dma_mask);
+       if (!iova)
+               goto error;
+       /*
+        * Check if DMAR supports zero-length reads on write only
+        * mappings..
+        */
+       if (dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL || \
+                       !cap_zlr(iommu->cap))
+               prot |= DMA_PTE_READ;
+       if (dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL)
+               prot |= DMA_PTE_WRITE;
+       /*
+        * paddr - (paddr + size) might be partial page, we should map the whole
+        * page.  Note: if two part of one page are separately mapped, we
+        * might have two guest_addr mapping to the same host paddr, but this
+        * is not a big problem
+        */
+       ret = domain_pfn_mapping(domain, mm_to_dma_pfn(iova->pfn_lo),
+                                mm_to_dma_pfn(paddr_pfn), size, prot);
+       if (ret)
+               goto error;
+       /* it's a non-present to present mapping. Only flush if caching mode */
+       if (cap_caching_mode(iommu->cap))
+               iommu_flush_iotlb_psi(iommu, domain->id, mm_to_dma_pfn(iova->pfn_lo), size, 1);
+       else
+               iommu_flush_write_buffer(iommu);
+       start_paddr = (phys_addr_t)iova->pfn_lo << PAGE_SHIFT;
+       start_paddr += paddr & ~PAGE_MASK;
+       return start_paddr;
+ error:
+       if (iova)
+               __free_iova(&domain->iovad, iova);
+       printk(KERN_ERR"Device %s request: %zx@%llx dir %d --- failed\n",
+               pci_name(pdev), size, (unsigned long long)paddr, dir);
+       return 0;
+ }
+ static dma_addr_t intel_map_page(struct device *dev, struct page *page,
+                                unsigned long offset, size_t size,
+                                enum dma_data_direction dir,
+                                struct dma_attrs *attrs)
+ {
+       return __intel_map_single(dev, page_to_phys(page) + offset, size,
+                                 dir, to_pci_dev(dev)->dma_mask);
+ }
+ static void flush_unmaps(void)
+ {
+       int i, j;
+       timer_on = 0;
+       /* just flush them all */
+       for (i = 0; i < g_num_of_iommus; i++) {
+               struct intel_iommu *iommu = g_iommus[i];
+               if (!iommu)
+                       continue;
+               if (!deferred_flush[i].next)
+                       continue;
+               /* In caching mode, global flushes turn emulation expensive */
+               if (!cap_caching_mode(iommu->cap))
+                       iommu->flush.flush_iotlb(iommu, 0, 0, 0,
+                                        DMA_TLB_GLOBAL_FLUSH);
+               for (j = 0; j < deferred_flush[i].next; j++) {
+                       unsigned long mask;
+                       struct iova *iova = deferred_flush[i].iova[j];
+                       struct dmar_domain *domain = deferred_flush[i].domain[j];
+                       /* On real hardware multiple invalidations are expensive */
+                       if (cap_caching_mode(iommu->cap))
+                               iommu_flush_iotlb_psi(iommu, domain->id,
+                               iova->pfn_lo, iova->pfn_hi - iova->pfn_lo + 1, 0);
+                       else {
+                               mask = ilog2(mm_to_dma_pfn(iova->pfn_hi - iova->pfn_lo + 1));
+                               iommu_flush_dev_iotlb(deferred_flush[i].domain[j],
+                                               (uint64_t)iova->pfn_lo << PAGE_SHIFT, mask);
+                       }
+                       __free_iova(&deferred_flush[i].domain[j]->iovad, iova);
+               }
+               deferred_flush[i].next = 0;
+       }
+       list_size = 0;
+ }
+ static void flush_unmaps_timeout(unsigned long data)
+ {
+       unsigned long flags;
+       spin_lock_irqsave(&async_umap_flush_lock, flags);
+       flush_unmaps();
+       spin_unlock_irqrestore(&async_umap_flush_lock, flags);
+ }
+ static void add_unmap(struct dmar_domain *dom, struct iova *iova)
+ {
+       unsigned long flags;
+       int next, iommu_id;
+       struct intel_iommu *iommu;
+       spin_lock_irqsave(&async_umap_flush_lock, flags);
+       if (list_size == HIGH_WATER_MARK)
+               flush_unmaps();
+       iommu = domain_get_iommu(dom);
+       iommu_id = iommu->seq_id;
+       next = deferred_flush[iommu_id].next;
+       deferred_flush[iommu_id].domain[next] = dom;
+       deferred_flush[iommu_id].iova[next] = iova;
+       deferred_flush[iommu_id].next++;
+       if (!timer_on) {
+               mod_timer(&unmap_timer, jiffies + msecs_to_jiffies(10));
+               timer_on = 1;
+       }
+       list_size++;
+       spin_unlock_irqrestore(&async_umap_flush_lock, flags);
+ }
+ static void intel_unmap_page(struct device *dev, dma_addr_t dev_addr,
+                            size_t size, enum dma_data_direction dir,
+                            struct dma_attrs *attrs)
+ {
+       struct pci_dev *pdev = to_pci_dev(dev);
+       struct dmar_domain *domain;
+       unsigned long start_pfn, last_pfn;
+       struct iova *iova;
+       struct intel_iommu *iommu;
+       if (iommu_no_mapping(dev))
+               return;
+       domain = find_domain(pdev);
+       BUG_ON(!domain);
+       iommu = domain_get_iommu(domain);
+       iova = find_iova(&domain->iovad, IOVA_PFN(dev_addr));
+       if (WARN_ONCE(!iova, "Driver unmaps unmatched page at PFN %llx\n",
+                     (unsigned long long)dev_addr))
+               return;
+       start_pfn = mm_to_dma_pfn(iova->pfn_lo);
+       last_pfn = mm_to_dma_pfn(iova->pfn_hi + 1) - 1;
+       pr_debug("Device %s unmapping: pfn %lx-%lx\n",
+                pci_name(pdev), start_pfn, last_pfn);
+       /*  clear the whole page */
+       dma_pte_clear_range(domain, start_pfn, last_pfn);
+       /* free page tables */
+       dma_pte_free_pagetable(domain, start_pfn, last_pfn);
+       if (intel_iommu_strict) {
+               iommu_flush_iotlb_psi(iommu, domain->id, start_pfn,
+                                     last_pfn - start_pfn + 1, 0);
+               /* free iova */
+               __free_iova(&domain->iovad, iova);
+       } else {
+               add_unmap(domain, iova);
+               /*
+                * queue up the release of the unmap to save the 1/6th of the
+                * cpu used up by the iotlb flush operation...
+                */
+       }
+ }
+ static void *intel_alloc_coherent(struct device *hwdev, size_t size,
+                                 dma_addr_t *dma_handle, gfp_t flags)
+ {
+       void *vaddr;
+       int order;
+       size = PAGE_ALIGN(size);
+       order = get_order(size);
+       if (!iommu_no_mapping(hwdev))
+               flags &= ~(GFP_DMA | GFP_DMA32);
+       else if (hwdev->coherent_dma_mask < dma_get_required_mask(hwdev)) {
+               if (hwdev->coherent_dma_mask < DMA_BIT_MASK(32))
+                       flags |= GFP_DMA;
+               else
+                       flags |= GFP_DMA32;
+       }
+       vaddr = (void *)__get_free_pages(flags, order);
+       if (!vaddr)
+               return NULL;
+       memset(vaddr, 0, size);
+       *dma_handle = __intel_map_single(hwdev, virt_to_bus(vaddr), size,
+                                        DMA_BIDIRECTIONAL,
+                                        hwdev->coherent_dma_mask);
+       if (*dma_handle)
+               return vaddr;
+       free_pages((unsigned long)vaddr, order);
+       return NULL;
+ }
+ static void intel_free_coherent(struct device *hwdev, size_t size, void *vaddr,
+                               dma_addr_t dma_handle)
+ {
+       int order;
+       size = PAGE_ALIGN(size);
+       order = get_order(size);
+       intel_unmap_page(hwdev, dma_handle, size, DMA_BIDIRECTIONAL, NULL);
+       free_pages((unsigned long)vaddr, order);
+ }
+ static void intel_unmap_sg(struct device *hwdev, struct scatterlist *sglist,
+                          int nelems, enum dma_data_direction dir,
+                          struct dma_attrs *attrs)
+ {
+       struct pci_dev *pdev = to_pci_dev(hwdev);
+       struct dmar_domain *domain;
+       unsigned long start_pfn, last_pfn;
+       struct iova *iova;
+       struct intel_iommu *iommu;
+       if (iommu_no_mapping(hwdev))
+               return;
+       domain = find_domain(pdev);
+       BUG_ON(!domain);
+       iommu = domain_get_iommu(domain);
+       iova = find_iova(&domain->iovad, IOVA_PFN(sglist[0].dma_address));
+       if (WARN_ONCE(!iova, "Driver unmaps unmatched sglist at PFN %llx\n",
+                     (unsigned long long)sglist[0].dma_address))
+               return;
+       start_pfn = mm_to_dma_pfn(iova->pfn_lo);
+       last_pfn = mm_to_dma_pfn(iova->pfn_hi + 1) - 1;
+       /*  clear the whole page */
+       dma_pte_clear_range(domain, start_pfn, last_pfn);
+       /* free page tables */
+       dma_pte_free_pagetable(domain, start_pfn, last_pfn);
+       if (intel_iommu_strict) {
+               iommu_flush_iotlb_psi(iommu, domain->id, start_pfn,
+                                     last_pfn - start_pfn + 1, 0);
+               /* free iova */
+               __free_iova(&domain->iovad, iova);
+       } else {
+               add_unmap(domain, iova);
+               /*
+                * queue up the release of the unmap to save the 1/6th of the
+                * cpu used up by the iotlb flush operation...
+                */
+       }
+ }
+ static int intel_nontranslate_map_sg(struct device *hddev,
+       struct scatterlist *sglist, int nelems, int dir)
+ {
+       int i;
+       struct scatterlist *sg;
+       for_each_sg(sglist, sg, nelems, i) {
+               BUG_ON(!sg_page(sg));
+               sg->dma_address = page_to_phys(sg_page(sg)) + sg->offset;
+               sg->dma_length = sg->length;
+       }
+       return nelems;
+ }
+ static int intel_map_sg(struct device *hwdev, struct scatterlist *sglist, int nelems,
+                       enum dma_data_direction dir, struct dma_attrs *attrs)
+ {
+       int i;
+       struct pci_dev *pdev = to_pci_dev(hwdev);
+       struct dmar_domain *domain;
+       size_t size = 0;
+       int prot = 0;
+       struct iova *iova = NULL;
+       int ret;
+       struct scatterlist *sg;
+       unsigned long start_vpfn;
+       struct intel_iommu *iommu;
+       BUG_ON(dir == DMA_NONE);
+       if (iommu_no_mapping(hwdev))
+               return intel_nontranslate_map_sg(hwdev, sglist, nelems, dir);
+       domain = get_valid_domain_for_dev(pdev);
+       if (!domain)
+               return 0;
+       iommu = domain_get_iommu(domain);
+       for_each_sg(sglist, sg, nelems, i)
+               size += aligned_nrpages(sg->offset, sg->length);
+       iova = intel_alloc_iova(hwdev, domain, dma_to_mm_pfn(size),
+                               pdev->dma_mask);
+       if (!iova) {
+               sglist->dma_length = 0;
+               return 0;
+       }
+       /*
+        * Check if DMAR supports zero-length reads on write only
+        * mappings..
+        */
+       if (dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL || \
+                       !cap_zlr(iommu->cap))
+               prot |= DMA_PTE_READ;
+       if (dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL)
+               prot |= DMA_PTE_WRITE;
+       start_vpfn = mm_to_dma_pfn(iova->pfn_lo);
+       ret = domain_sg_mapping(domain, start_vpfn, sglist, size, prot);
+       if (unlikely(ret)) {
+               /*  clear the page */
+               dma_pte_clear_range(domain, start_vpfn,
+                                   start_vpfn + size - 1);
+               /* free page tables */
+               dma_pte_free_pagetable(domain, start_vpfn,
+                                      start_vpfn + size - 1);
+               /* free iova */
+               __free_iova(&domain->iovad, iova);
+               return 0;
+       }
+       /* it's a non-present to present mapping. Only flush if caching mode */
+       if (cap_caching_mode(iommu->cap))
+               iommu_flush_iotlb_psi(iommu, domain->id, start_vpfn, size, 1);
+       else
+               iommu_flush_write_buffer(iommu);
+       return nelems;
+ }
+ static int intel_mapping_error(struct device *dev, dma_addr_t dma_addr)
+ {
+       return !dma_addr;
+ }
+ struct dma_map_ops intel_dma_ops = {
+       .alloc_coherent = intel_alloc_coherent,
+       .free_coherent = intel_free_coherent,
+       .map_sg = intel_map_sg,
+       .unmap_sg = intel_unmap_sg,
+       .map_page = intel_map_page,
+       .unmap_page = intel_unmap_page,
+       .mapping_error = intel_mapping_error,
+ };
+ static inline int iommu_domain_cache_init(void)
+ {
+       int ret = 0;
+       iommu_domain_cache = kmem_cache_create("iommu_domain",
+                                        sizeof(struct dmar_domain),
+                                        0,
+                                        SLAB_HWCACHE_ALIGN,
+                                        NULL);
+       if (!iommu_domain_cache) {
+               printk(KERN_ERR "Couldn't create iommu_domain cache\n");
+               ret = -ENOMEM;
+       }
+       return ret;
+ }
+ static inline int iommu_devinfo_cache_init(void)
+ {
+       int ret = 0;
+       iommu_devinfo_cache = kmem_cache_create("iommu_devinfo",
+                                        sizeof(struct device_domain_info),
+                                        0,
+                                        SLAB_HWCACHE_ALIGN,
+                                        NULL);
+       if (!iommu_devinfo_cache) {
+               printk(KERN_ERR "Couldn't create devinfo cache\n");
+               ret = -ENOMEM;
+       }
+       return ret;
+ }
+ static inline int iommu_iova_cache_init(void)
+ {
+       int ret = 0;
+       iommu_iova_cache = kmem_cache_create("iommu_iova",
+                                        sizeof(struct iova),
+                                        0,
+                                        SLAB_HWCACHE_ALIGN,
+                                        NULL);
+       if (!iommu_iova_cache) {
+               printk(KERN_ERR "Couldn't create iova cache\n");
+               ret = -ENOMEM;
+       }
+       return ret;
+ }
+ static int __init iommu_init_mempool(void)
+ {
+       int ret;
+       ret = iommu_iova_cache_init();
+       if (ret)
+               return ret;
+       ret = iommu_domain_cache_init();
+       if (ret)
+               goto domain_error;
+       ret = iommu_devinfo_cache_init();
+       if (!ret)
+               return ret;
+       kmem_cache_destroy(iommu_domain_cache);
+ domain_error:
+       kmem_cache_destroy(iommu_iova_cache);
+       return -ENOMEM;
+ }
+ static void __init iommu_exit_mempool(void)
+ {
+       kmem_cache_destroy(iommu_devinfo_cache);
+       kmem_cache_destroy(iommu_domain_cache);
+       kmem_cache_destroy(iommu_iova_cache);
+ }
+ static void quirk_ioat_snb_local_iommu(struct pci_dev *pdev)
+ {
+       struct dmar_drhd_unit *drhd;
+       u32 vtbar;
+       int rc;
+       /* We know that this device on this chipset has its own IOMMU.
+        * If we find it under a different IOMMU, then the BIOS is lying
+        * to us. Hope that the IOMMU for this device is actually
+        * disabled, and it needs no translation...
+        */
+       rc = pci_bus_read_config_dword(pdev->bus, PCI_DEVFN(0, 0), 0xb0, &vtbar);
+       if (rc) {
+               /* "can't" happen */
+               dev_info(&pdev->dev, "failed to run vt-d quirk\n");
+               return;
+       }
+       vtbar &= 0xffff0000;
+       /* we know that the this iommu should be at offset 0xa000 from vtbar */
+       drhd = dmar_find_matched_drhd_unit(pdev);
+       if (WARN_TAINT_ONCE(!drhd || drhd->reg_base_addr - vtbar != 0xa000,
+                           TAINT_FIRMWARE_WORKAROUND,
+                           "BIOS assigned incorrect VT-d unit for Intel(R) QuickData Technology device\n"))
+               pdev->dev.archdata.iommu = DUMMY_DEVICE_DOMAIN_INFO;
+ }
+ DECLARE_PCI_FIXUP_ENABLE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IOAT_SNB, quirk_ioat_snb_local_iommu);
+ static void __init init_no_remapping_devices(void)
+ {
+       struct dmar_drhd_unit *drhd;
+       for_each_drhd_unit(drhd) {
+               if (!drhd->include_all) {
+                       int i;
+                       for (i = 0; i < drhd->devices_cnt; i++)
+                               if (drhd->devices[i] != NULL)
+                                       break;
+                       /* ignore DMAR unit if no pci devices exist */
+                       if (i == drhd->devices_cnt)
+                               drhd->ignored = 1;
+               }
+       }
+       for_each_drhd_unit(drhd) {
+               int i;
+               if (drhd->ignored || drhd->include_all)
+                       continue;
+               for (i = 0; i < drhd->devices_cnt; i++)
+                       if (drhd->devices[i] &&
+                           !IS_GFX_DEVICE(drhd->devices[i]))
+                               break;
+               if (i < drhd->devices_cnt)
+                       continue;
+               /* This IOMMU has *only* gfx devices. Either bypass it or
+                  set the gfx_mapped flag, as appropriate */
+               if (dmar_map_gfx) {
+                       intel_iommu_gfx_mapped = 1;
+               } else {
+                       drhd->ignored = 1;
+                       for (i = 0; i < drhd->devices_cnt; i++) {
+                               if (!drhd->devices[i])
+                                       continue;
+                               drhd->devices[i]->dev.archdata.iommu = DUMMY_DEVICE_DOMAIN_INFO;
+                       }
+               }
+       }
+ }
+ #ifdef CONFIG_SUSPEND
+ static int init_iommu_hw(void)
+ {
+       struct dmar_drhd_unit *drhd;
+       struct intel_iommu *iommu = NULL;
+       for_each_active_iommu(iommu, drhd)
+               if (iommu->qi)
+                       dmar_reenable_qi(iommu);
+       for_each_iommu(iommu, drhd) {
+               if (drhd->ignored) {
+                       /*
+                        * we always have to disable PMRs or DMA may fail on
+                        * this device
+                        */
+                       if (force_on)
+                               iommu_disable_protect_mem_regions(iommu);
+                       continue;
+               }
+       
+               iommu_flush_write_buffer(iommu);
+               iommu_set_root_entry(iommu);
+               iommu->flush.flush_context(iommu, 0, 0, 0,
+                                          DMA_CCMD_GLOBAL_INVL);
+               iommu->flush.flush_iotlb(iommu, 0, 0, 0,
+                                        DMA_TLB_GLOBAL_FLUSH);
+               if (iommu_enable_translation(iommu))
+                       return 1;
+               iommu_disable_protect_mem_regions(iommu);
+       }
+       return 0;
+ }
+ static void iommu_flush_all(void)
+ {
+       struct dmar_drhd_unit *drhd;
+       struct intel_iommu *iommu;
+       for_each_active_iommu(iommu, drhd) {
+               iommu->flush.flush_context(iommu, 0, 0, 0,
+                                          DMA_CCMD_GLOBAL_INVL);
+               iommu->flush.flush_iotlb(iommu, 0, 0, 0,
+                                        DMA_TLB_GLOBAL_FLUSH);
+       }
+ }
+ static int iommu_suspend(void)
+ {
+       struct dmar_drhd_unit *drhd;
+       struct intel_iommu *iommu = NULL;
+       unsigned long flag;
+       for_each_active_iommu(iommu, drhd) {
+               iommu->iommu_state = kzalloc(sizeof(u32) * MAX_SR_DMAR_REGS,
+                                                GFP_ATOMIC);
+               if (!iommu->iommu_state)
+                       goto nomem;
+       }
+       iommu_flush_all();
+       for_each_active_iommu(iommu, drhd) {
+               iommu_disable_translation(iommu);
+               raw_spin_lock_irqsave(&iommu->register_lock, flag);
+               iommu->iommu_state[SR_DMAR_FECTL_REG] =
+                       readl(iommu->reg + DMAR_FECTL_REG);
+               iommu->iommu_state[SR_DMAR_FEDATA_REG] =
+                       readl(iommu->reg + DMAR_FEDATA_REG);
+               iommu->iommu_state[SR_DMAR_FEADDR_REG] =
+                       readl(iommu->reg + DMAR_FEADDR_REG);
+               iommu->iommu_state[SR_DMAR_FEUADDR_REG] =
+                       readl(iommu->reg + DMAR_FEUADDR_REG);
+               raw_spin_unlock_irqrestore(&iommu->register_lock, flag);
+       }
+       return 0;
+ nomem:
+       for_each_active_iommu(iommu, drhd)
+               kfree(iommu->iommu_state);
+       return -ENOMEM;
+ }
+ static void iommu_resume(void)
+ {
+       struct dmar_drhd_unit *drhd;
+       struct intel_iommu *iommu = NULL;
+       unsigned long flag;
+       if (init_iommu_hw()) {
+               if (force_on)
+                       panic("tboot: IOMMU setup failed, DMAR can not resume!\n");
+               else
+                       WARN(1, "IOMMU setup failed, DMAR can not resume!\n");
+               return;
+       }
+       for_each_active_iommu(iommu, drhd) {
+               raw_spin_lock_irqsave(&iommu->register_lock, flag);
+               writel(iommu->iommu_state[SR_DMAR_FECTL_REG],
+                       iommu->reg + DMAR_FECTL_REG);
+               writel(iommu->iommu_state[SR_DMAR_FEDATA_REG],
+                       iommu->reg + DMAR_FEDATA_REG);
+               writel(iommu->iommu_state[SR_DMAR_FEADDR_REG],
+                       iommu->reg + DMAR_FEADDR_REG);
+               writel(iommu->iommu_state[SR_DMAR_FEUADDR_REG],
+                       iommu->reg + DMAR_FEUADDR_REG);
+               raw_spin_unlock_irqrestore(&iommu->register_lock, flag);
+       }
+       for_each_active_iommu(iommu, drhd)
+               kfree(iommu->iommu_state);
+ }
+ static struct syscore_ops iommu_syscore_ops = {
+       .resume         = iommu_resume,
+       .suspend        = iommu_suspend,
+ };
+ static void __init init_iommu_pm_ops(void)
+ {
+       register_syscore_ops(&iommu_syscore_ops);
+ }
+ #else
+ static inline void init_iommu_pm_ops(void) {}
+ #endif        /* CONFIG_PM */
+ LIST_HEAD(dmar_rmrr_units);
+ static void __init dmar_register_rmrr_unit(struct dmar_rmrr_unit *rmrr)
+ {
+       list_add(&rmrr->list, &dmar_rmrr_units);
+ }
+ int __init dmar_parse_one_rmrr(struct acpi_dmar_header *header)
+ {
+       struct acpi_dmar_reserved_memory *rmrr;
+       struct dmar_rmrr_unit *rmrru;
+       rmrru = kzalloc(sizeof(*rmrru), GFP_KERNEL);
+       if (!rmrru)
+               return -ENOMEM;
+       rmrru->hdr = header;
+       rmrr = (struct acpi_dmar_reserved_memory *)header;
+       rmrru->base_address = rmrr->base_address;
+       rmrru->end_address = rmrr->end_address;
+       dmar_register_rmrr_unit(rmrru);
+       return 0;
+ }
+ static int __init
+ rmrr_parse_dev(struct dmar_rmrr_unit *rmrru)
+ {
+       struct acpi_dmar_reserved_memory *rmrr;
+       int ret;
+       rmrr = (struct acpi_dmar_reserved_memory *) rmrru->hdr;
+       ret = dmar_parse_dev_scope((void *)(rmrr + 1),
+               ((void *)rmrr) + rmrr->header.length,
+               &rmrru->devices_cnt, &rmrru->devices, rmrr->segment);
+       if (ret || (rmrru->devices_cnt == 0)) {
+               list_del(&rmrru->list);
+               kfree(rmrru);
+       }
+       return ret;
+ }
+ static LIST_HEAD(dmar_atsr_units);
+ int __init dmar_parse_one_atsr(struct acpi_dmar_header *hdr)
+ {
+       struct acpi_dmar_atsr *atsr;
+       struct dmar_atsr_unit *atsru;
+       atsr = container_of(hdr, struct acpi_dmar_atsr, header);
+       atsru = kzalloc(sizeof(*atsru), GFP_KERNEL);
+       if (!atsru)
+               return -ENOMEM;
+       atsru->hdr = hdr;
+       atsru->include_all = atsr->flags & 0x1;
+       list_add(&atsru->list, &dmar_atsr_units);
+       return 0;
+ }
+ static int __init atsr_parse_dev(struct dmar_atsr_unit *atsru)
+ {
+       int rc;
+       struct acpi_dmar_atsr *atsr;
+       if (atsru->include_all)
+               return 0;
+       atsr = container_of(atsru->hdr, struct acpi_dmar_atsr, header);
+       rc = dmar_parse_dev_scope((void *)(atsr + 1),
+                               (void *)atsr + atsr->header.length,
+                               &atsru->devices_cnt, &atsru->devices,
+                               atsr->segment);
+       if (rc || !atsru->devices_cnt) {
+               list_del(&atsru->list);
+               kfree(atsru);
+       }
+       return rc;
+ }
+ int dmar_find_matched_atsr_unit(struct pci_dev *dev)
+ {
+       int i;
+       struct pci_bus *bus;
+       struct acpi_dmar_atsr *atsr;
+       struct dmar_atsr_unit *atsru;
+       dev = pci_physfn(dev);
+       list_for_each_entry(atsru, &dmar_atsr_units, list) {
+               atsr = container_of(atsru->hdr, struct acpi_dmar_atsr, header);
+               if (atsr->segment == pci_domain_nr(dev->bus))
+                       goto found;
+       }
+       return 0;
+ found:
+       for (bus = dev->bus; bus; bus = bus->parent) {
+               struct pci_dev *bridge = bus->self;
+               if (!bridge || !pci_is_pcie(bridge) ||
+                   bridge->pcie_type == PCI_EXP_TYPE_PCI_BRIDGE)
+                       return 0;
+               if (bridge->pcie_type == PCI_EXP_TYPE_ROOT_PORT) {
+                       for (i = 0; i < atsru->devices_cnt; i++)
+                               if (atsru->devices[i] == bridge)
+                                       return 1;
+                       break;
+               }
+       }
+       if (atsru->include_all)
+               return 1;
+       return 0;
+ }
+ int dmar_parse_rmrr_atsr_dev(void)
+ {
+       struct dmar_rmrr_unit *rmrr, *rmrr_n;
+       struct dmar_atsr_unit *atsr, *atsr_n;
+       int ret = 0;
+       list_for_each_entry_safe(rmrr, rmrr_n, &dmar_rmrr_units, list) {
+               ret = rmrr_parse_dev(rmrr);
+               if (ret)
+                       return ret;
+       }
+       list_for_each_entry_safe(atsr, atsr_n, &dmar_atsr_units, list) {
+               ret = atsr_parse_dev(atsr);
+               if (ret)
+                       return ret;
+       }
+       return ret;
+ }
+ /*
+  * Here we only respond to action of unbound device from driver.
+  *
+  * Added device is not attached to its DMAR domain here yet. That will happen
+  * when mapping the device to iova.
+  */
+ static int device_notifier(struct notifier_block *nb,
+                                 unsigned long action, void *data)
+ {
+       struct device *dev = data;
+       struct pci_dev *pdev = to_pci_dev(dev);
+       struct dmar_domain *domain;
+       if (iommu_no_mapping(dev))
+               return 0;
+       domain = find_domain(pdev);
+       if (!domain)
+               return 0;
+       if (action == BUS_NOTIFY_UNBOUND_DRIVER && !iommu_pass_through) {
+               domain_remove_one_dev_info(domain, pdev);
+               if (!(domain->flags & DOMAIN_FLAG_VIRTUAL_MACHINE) &&
+                   !(domain->flags & DOMAIN_FLAG_STATIC_IDENTITY) &&
+                   list_empty(&domain->devices))
+                       domain_exit(domain);
+       }
+       return 0;
+ }
+ static struct notifier_block device_nb = {
+       .notifier_call = device_notifier,
+ };
+ int __init intel_iommu_init(void)
+ {
+       int ret = 0;
+       /* VT-d is required for a TXT/tboot launch, so enforce that */
+       force_on = tboot_force_iommu();
+       if (dmar_table_init()) {
+               if (force_on)
+                       panic("tboot: Failed to initialize DMAR table\n");
+               return  -ENODEV;
+       }
+       if (dmar_dev_scope_init() < 0) {
+               if (force_on)
+                       panic("tboot: Failed to initialize DMAR device scope\n");
+               return  -ENODEV;
+       }
+       if (no_iommu || dmar_disabled)
+               return -ENODEV;
+       if (iommu_init_mempool()) {
+               if (force_on)
+                       panic("tboot: Failed to initialize iommu memory\n");
+               return  -ENODEV;
+       }
+       if (list_empty(&dmar_rmrr_units))
+               printk(KERN_INFO "DMAR: No RMRR found\n");
+       if (list_empty(&dmar_atsr_units))
+               printk(KERN_INFO "DMAR: No ATSR found\n");
+       if (dmar_init_reserved_ranges()) {
+               if (force_on)
+                       panic("tboot: Failed to reserve iommu ranges\n");
+               return  -ENODEV;
+       }
+       init_no_remapping_devices();
+       ret = init_dmars();
+       if (ret) {
+               if (force_on)
+                       panic("tboot: Failed to initialize DMARs\n");
+               printk(KERN_ERR "IOMMU: dmar init failed\n");
+               put_iova_domain(&reserved_iova_list);
+               iommu_exit_mempool();
+               return ret;
+       }
+       printk(KERN_INFO
+       "PCI-DMA: Intel(R) Virtualization Technology for Directed I/O\n");
+       init_timer(&unmap_timer);
+ #ifdef CONFIG_SWIOTLB
+       swiotlb = 0;
+ #endif
+       dma_ops = &intel_dma_ops;
+       init_iommu_pm_ops();
+       bus_set_iommu(&pci_bus_type, &intel_iommu_ops);
+       bus_register_notifier(&pci_bus_type, &device_nb);
+       return 0;
+ }
+ static void iommu_detach_dependent_devices(struct intel_iommu *iommu,
+                                          struct pci_dev *pdev)
+ {
+       struct pci_dev *tmp, *parent;
+       if (!iommu || !pdev)
+               return;
+       /* dependent device detach */
+       tmp = pci_find_upstream_pcie_bridge(pdev);
+       /* Secondary interface's bus number and devfn 0 */
+       if (tmp) {
+               parent = pdev->bus->self;
+               while (parent != tmp) {
+                       iommu_detach_dev(iommu, parent->bus->number,
+                                        parent->devfn);
+                       parent = parent->bus->self;
+               }
+               if (pci_is_pcie(tmp)) /* this is a PCIe-to-PCI bridge */
+                       iommu_detach_dev(iommu,
+                               tmp->subordinate->number, 0);
+               else /* this is a legacy PCI bridge */
+                       iommu_detach_dev(iommu, tmp->bus->number,
+                                        tmp->devfn);
+       }
+ }
+ static void domain_remove_one_dev_info(struct dmar_domain *domain,
+                                         struct pci_dev *pdev)
+ {
+       struct device_domain_info *info;
+       struct intel_iommu *iommu;
+       unsigned long flags;
+       int found = 0;
+       struct list_head *entry, *tmp;
+       iommu = device_to_iommu(pci_domain_nr(pdev->bus), pdev->bus->number,
+                               pdev->devfn);
+       if (!iommu)
+               return;
+       spin_lock_irqsave(&device_domain_lock, flags);
+       list_for_each_safe(entry, tmp, &domain->devices) {
+               info = list_entry(entry, struct device_domain_info, link);
+               if (info->segment == pci_domain_nr(pdev->bus) &&
+                   info->bus == pdev->bus->number &&
+                   info->devfn == pdev->devfn) {
+                       list_del(&info->link);
+                       list_del(&info->global);
+                       if (info->dev)
+                               info->dev->dev.archdata.iommu = NULL;
+                       spin_unlock_irqrestore(&device_domain_lock, flags);
+                       iommu_disable_dev_iotlb(info);
+                       iommu_detach_dev(iommu, info->bus, info->devfn);
+                       iommu_detach_dependent_devices(iommu, pdev);
+                       free_devinfo_mem(info);
+                       spin_lock_irqsave(&device_domain_lock, flags);
+                       if (found)
+                               break;
+                       else
+                               continue;
+               }
+               /* if there is no other devices under the same iommu
+                * owned by this domain, clear this iommu in iommu_bmp
+                * update iommu count and coherency
+                */
+               if (iommu == device_to_iommu(info->segment, info->bus,
+                                           info->devfn))
+                       found = 1;
+       }
+       spin_unlock_irqrestore(&device_domain_lock, flags);
+       if (found == 0) {
+               unsigned long tmp_flags;
+               spin_lock_irqsave(&domain->iommu_lock, tmp_flags);
+               clear_bit(iommu->seq_id, &domain->iommu_bmp);
+               domain->iommu_count--;
+               domain_update_iommu_cap(domain);
+               spin_unlock_irqrestore(&domain->iommu_lock, tmp_flags);
+               if (!(domain->flags & DOMAIN_FLAG_VIRTUAL_MACHINE) &&
+                   !(domain->flags & DOMAIN_FLAG_STATIC_IDENTITY)) {
+                       spin_lock_irqsave(&iommu->lock, tmp_flags);
+                       clear_bit(domain->id, iommu->domain_ids);
+                       iommu->domains[domain->id] = NULL;
+                       spin_unlock_irqrestore(&iommu->lock, tmp_flags);
+               }
+       }
+ }
+ static void vm_domain_remove_all_dev_info(struct dmar_domain *domain)
+ {
+       struct device_domain_info *info;
+       struct intel_iommu *iommu;
+       unsigned long flags1, flags2;
+       spin_lock_irqsave(&device_domain_lock, flags1);
+       while (!list_empty(&domain->devices)) {
+               info = list_entry(domain->devices.next,
+                       struct device_domain_info, link);
+               list_del(&info->link);
+               list_del(&info->global);
+               if (info->dev)
+                       info->dev->dev.archdata.iommu = NULL;
+               spin_unlock_irqrestore(&device_domain_lock, flags1);
+               iommu_disable_dev_iotlb(info);
+               iommu = device_to_iommu(info->segment, info->bus, info->devfn);
+               iommu_detach_dev(iommu, info->bus, info->devfn);
+               iommu_detach_dependent_devices(iommu, info->dev);
+               /* clear this iommu in iommu_bmp, update iommu count
+                * and capabilities
+                */
+               spin_lock_irqsave(&domain->iommu_lock, flags2);
+               if (test_and_clear_bit(iommu->seq_id,
+                                      &domain->iommu_bmp)) {
+                       domain->iommu_count--;
+                       domain_update_iommu_cap(domain);
+               }
+               spin_unlock_irqrestore(&domain->iommu_lock, flags2);
+               free_devinfo_mem(info);
+               spin_lock_irqsave(&device_domain_lock, flags1);
+       }
+       spin_unlock_irqrestore(&device_domain_lock, flags1);
+ }
+ /* domain id for virtual machine, it won't be set in context */
+ static unsigned long vm_domid;
+ static struct dmar_domain *iommu_alloc_vm_domain(void)
+ {
+       struct dmar_domain *domain;
+       domain = alloc_domain_mem();
+       if (!domain)
+               return NULL;
+       domain->id = vm_domid++;
+       domain->nid = -1;
+       memset(&domain->iommu_bmp, 0, sizeof(unsigned long));
+       domain->flags = DOMAIN_FLAG_VIRTUAL_MACHINE;
+       return domain;
+ }
+ static int md_domain_init(struct dmar_domain *domain, int guest_width)
+ {
+       int adjust_width;
+       init_iova_domain(&domain->iovad, DMA_32BIT_PFN);
+       spin_lock_init(&domain->iommu_lock);
+       domain_reserve_special_ranges(domain);
+       /* calculate AGAW */
+       domain->gaw = guest_width;
+       adjust_width = guestwidth_to_adjustwidth(guest_width);
+       domain->agaw = width_to_agaw(adjust_width);
+       INIT_LIST_HEAD(&domain->devices);
+       domain->iommu_count = 0;
+       domain->iommu_coherency = 0;
+       domain->iommu_snooping = 0;
+       domain->iommu_superpage = 0;
+       domain->max_addr = 0;
+       domain->nid = -1;
+       /* always allocate the top pgd */
+       domain->pgd = (struct dma_pte *)alloc_pgtable_page(domain->nid);
+       if (!domain->pgd)
+               return -ENOMEM;
+       domain_flush_cache(domain, domain->pgd, PAGE_SIZE);
+       return 0;
+ }
+ static void iommu_free_vm_domain(struct dmar_domain *domain)
+ {
+       unsigned long flags;
+       struct dmar_drhd_unit *drhd;
+       struct intel_iommu *iommu;
+       unsigned long i;
+       unsigned long ndomains;
+       for_each_drhd_unit(drhd) {
+               if (drhd->ignored)
+                       continue;
+               iommu = drhd->iommu;
+               ndomains = cap_ndoms(iommu->cap);
+               for_each_set_bit(i, iommu->domain_ids, ndomains) {
+                       if (iommu->domains[i] == domain) {
+                               spin_lock_irqsave(&iommu->lock, flags);
+                               clear_bit(i, iommu->domain_ids);
+                               iommu->domains[i] = NULL;
+                               spin_unlock_irqrestore(&iommu->lock, flags);
+                               break;
+                       }
+               }
+       }
+ }
+ static void vm_domain_exit(struct dmar_domain *domain)
+ {
+       /* Domain 0 is reserved, so dont process it */
+       if (!domain)
+               return;
+       vm_domain_remove_all_dev_info(domain);
+       /* destroy iovas */
+       put_iova_domain(&domain->iovad);
+       /* clear ptes */
+       dma_pte_clear_range(domain, 0, DOMAIN_MAX_PFN(domain->gaw));
+       /* free page tables */
+       dma_pte_free_pagetable(domain, 0, DOMAIN_MAX_PFN(domain->gaw));
+       iommu_free_vm_domain(domain);
+       free_domain_mem(domain);
+ }
+ static int intel_iommu_domain_init(struct iommu_domain *domain)
+ {
+       struct dmar_domain *dmar_domain;
+       dmar_domain = iommu_alloc_vm_domain();
+       if (!dmar_domain) {
+               printk(KERN_ERR
+                       "intel_iommu_domain_init: dmar_domain == NULL\n");
+               return -ENOMEM;
+       }
+       if (md_domain_init(dmar_domain, DEFAULT_DOMAIN_ADDRESS_WIDTH)) {
+               printk(KERN_ERR
+                       "intel_iommu_domain_init() failed\n");
+               vm_domain_exit(dmar_domain);
+               return -ENOMEM;
+       }
+       domain_update_iommu_cap(dmar_domain);
+       domain->priv = dmar_domain;
+       return 0;
+ }
+ static void intel_iommu_domain_destroy(struct iommu_domain *domain)
+ {
+       struct dmar_domain *dmar_domain = domain->priv;
+       domain->priv = NULL;
+       vm_domain_exit(dmar_domain);
+ }
+ static int intel_iommu_attach_device(struct iommu_domain *domain,
+                                    struct device *dev)
+ {
+       struct dmar_domain *dmar_domain = domain->priv;
+       struct pci_dev *pdev = to_pci_dev(dev);
+       struct intel_iommu *iommu;
+       int addr_width;
+       /* normally pdev is not mapped */
+       if (unlikely(domain_context_mapped(pdev))) {
+               struct dmar_domain *old_domain;
+               old_domain = find_domain(pdev);
+               if (old_domain) {
+                       if (dmar_domain->flags & DOMAIN_FLAG_VIRTUAL_MACHINE ||
+                           dmar_domain->flags & DOMAIN_FLAG_STATIC_IDENTITY)
+                               domain_remove_one_dev_info(old_domain, pdev);
+                       else
+                               domain_remove_dev_info(old_domain);
+               }
+       }
+       iommu = device_to_iommu(pci_domain_nr(pdev->bus), pdev->bus->number,
+                               pdev->devfn);
+       if (!iommu)
+               return -ENODEV;
+       /* check if this iommu agaw is sufficient for max mapped address */
+       addr_width = agaw_to_width(iommu->agaw);
+       if (addr_width > cap_mgaw(iommu->cap))
+               addr_width = cap_mgaw(iommu->cap);
+       if (dmar_domain->max_addr > (1LL << addr_width)) {
+               printk(KERN_ERR "%s: iommu width (%d) is not "
+                      "sufficient for the mapped address (%llx)\n",
+                      __func__, addr_width, dmar_domain->max_addr);
+               return -EFAULT;
+       }
+       dmar_domain->gaw = addr_width;
+       /*
+        * Knock out extra levels of page tables if necessary
+        */
+       while (iommu->agaw < dmar_domain->agaw) {
+               struct dma_pte *pte;
+               pte = dmar_domain->pgd;
+               if (dma_pte_present(pte)) {
+                       dmar_domain->pgd = (struct dma_pte *)
+                               phys_to_virt(dma_pte_addr(pte));
+                       free_pgtable_page(pte);
+               }
+               dmar_domain->agaw--;
+       }
+       return domain_add_dev_info(dmar_domain, pdev, CONTEXT_TT_MULTI_LEVEL);
+ }
+ static void intel_iommu_detach_device(struct iommu_domain *domain,
+                                     struct device *dev)
+ {
+       struct dmar_domain *dmar_domain = domain->priv;
+       struct pci_dev *pdev = to_pci_dev(dev);
+       domain_remove_one_dev_info(dmar_domain, pdev);
+ }
+ static int intel_iommu_map(struct iommu_domain *domain,
+                          unsigned long iova, phys_addr_t hpa,
+                          int gfp_order, int iommu_prot)
+ {
+       struct dmar_domain *dmar_domain = domain->priv;
+       u64 max_addr;
+       int prot = 0;
+       size_t size;
+       int ret;
+       if (iommu_prot & IOMMU_READ)
+               prot |= DMA_PTE_READ;
+       if (iommu_prot & IOMMU_WRITE)
+               prot |= DMA_PTE_WRITE;
+       if ((iommu_prot & IOMMU_CACHE) && dmar_domain->iommu_snooping)
+               prot |= DMA_PTE_SNP;
+       size     = PAGE_SIZE << gfp_order;
+       max_addr = iova + size;
+       if (dmar_domain->max_addr < max_addr) {
+               u64 end;
+               /* check if minimum agaw is sufficient for mapped address */
+               end = __DOMAIN_MAX_ADDR(dmar_domain->gaw) + 1;
+               if (end < max_addr) {
+                       printk(KERN_ERR "%s: iommu width (%d) is not "
+                              "sufficient for the mapped address (%llx)\n",
+                              __func__, dmar_domain->gaw, max_addr);
+                       return -EFAULT;
+               }
+               dmar_domain->max_addr = max_addr;
+       }
+       /* Round up size to next multiple of PAGE_SIZE, if it and
+          the low bits of hpa would take us onto the next page */
+       size = aligned_nrpages(hpa, size);
+       ret = domain_pfn_mapping(dmar_domain, iova >> VTD_PAGE_SHIFT,
+                                hpa >> VTD_PAGE_SHIFT, size, prot);
+       return ret;
+ }
+ static int intel_iommu_unmap(struct iommu_domain *domain,
+                            unsigned long iova, int gfp_order)
+ {
+       struct dmar_domain *dmar_domain = domain->priv;
+       size_t size = PAGE_SIZE << gfp_order;
+       int order;
+       order = dma_pte_clear_range(dmar_domain, iova >> VTD_PAGE_SHIFT,
+                           (iova + size - 1) >> VTD_PAGE_SHIFT);
+       if (dmar_domain->max_addr == iova + size)
+               dmar_domain->max_addr = iova;
+       return order;
+ }
+ static phys_addr_t intel_iommu_iova_to_phys(struct iommu_domain *domain,
+                                           unsigned long iova)
+ {
+       struct dmar_domain *dmar_domain = domain->priv;
+       struct dma_pte *pte;
+       u64 phys = 0;
+       pte = pfn_to_dma_pte(dmar_domain, iova >> VTD_PAGE_SHIFT, 0);
+       if (pte)
+               phys = dma_pte_addr(pte);
+       return phys;
+ }
+ static int intel_iommu_domain_has_cap(struct iommu_domain *domain,
+                                     unsigned long cap)
+ {
+       struct dmar_domain *dmar_domain = domain->priv;
+       if (cap == IOMMU_CAP_CACHE_COHERENCY)
+               return dmar_domain->iommu_snooping;
+       if (cap == IOMMU_CAP_INTR_REMAP)
+               return intr_remapping_enabled;
+       return 0;
+ }
+ static struct iommu_ops intel_iommu_ops = {
+       .domain_init    = intel_iommu_domain_init,
+       .domain_destroy = intel_iommu_domain_destroy,
+       .attach_dev     = intel_iommu_attach_device,
+       .detach_dev     = intel_iommu_detach_device,
+       .map            = intel_iommu_map,
+       .unmap          = intel_iommu_unmap,
+       .iova_to_phys   = intel_iommu_iova_to_phys,
+       .domain_has_cap = intel_iommu_domain_has_cap,
+ };
+ static void __devinit quirk_iommu_rwbf(struct pci_dev *dev)
+ {
+       /*
+        * Mobile 4 Series Chipset neglects to set RWBF capability,
+        * but needs it:
+        */
+       printk(KERN_INFO "DMAR: Forcing write-buffer flush capability\n");
+       rwbf_quirk = 1;
+       /* https://bugzilla.redhat.com/show_bug.cgi?id=538163 */
+       if (dev->revision == 0x07) {
+               printk(KERN_INFO "DMAR: Disabling IOMMU for graphics on this chipset\n");
+               dmar_map_gfx = 0;
+       }
+ }
+ DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x2a40, quirk_iommu_rwbf);
+ #define GGC 0x52
+ #define GGC_MEMORY_SIZE_MASK  (0xf << 8)
+ #define GGC_MEMORY_SIZE_NONE  (0x0 << 8)
+ #define GGC_MEMORY_SIZE_1M    (0x1 << 8)
+ #define GGC_MEMORY_SIZE_2M    (0x3 << 8)
+ #define GGC_MEMORY_VT_ENABLED (0x8 << 8)
+ #define GGC_MEMORY_SIZE_2M_VT (0x9 << 8)
+ #define GGC_MEMORY_SIZE_3M_VT (0xa << 8)
+ #define GGC_MEMORY_SIZE_4M_VT (0xb << 8)
+ static void __devinit quirk_calpella_no_shadow_gtt(struct pci_dev *dev)
+ {
+       unsigned short ggc;
+       if (pci_read_config_word(dev, GGC, &ggc))
+               return;
+       if (!(ggc & GGC_MEMORY_VT_ENABLED)) {
+               printk(KERN_INFO "DMAR: BIOS has allocated no shadow GTT; disabling IOMMU for graphics\n");
+               dmar_map_gfx = 0;
+       } else if (dmar_map_gfx) {
+               /* we have to ensure the gfx device is idle before we flush */
+               printk(KERN_INFO "DMAR: Disabling batched IOTLB flush on Ironlake\n");
+               intel_iommu_strict = 1;
+        }
+ }
+ DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x0040, quirk_calpella_no_shadow_gtt);
+ DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x0044, quirk_calpella_no_shadow_gtt);
+ DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x0062, quirk_calpella_no_shadow_gtt);
+ DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x006a, quirk_calpella_no_shadow_gtt);
+ /* On Tylersburg chipsets, some BIOSes have been known to enable the
+    ISOCH DMAR unit for the Azalia sound device, but not give it any
+    TLB entries, which causes it to deadlock. Check for that.  We do
+    this in a function called from init_dmars(), instead of in a PCI
+    quirk, because we don't want to print the obnoxious "BIOS broken"
+    message if VT-d is actually disabled.
+ */
+ static void __init check_tylersburg_isoch(void)
+ {
+       struct pci_dev *pdev;
+       uint32_t vtisochctrl;
+       /* If there's no Azalia in the system anyway, forget it. */
+       pdev = pci_get_device(PCI_VENDOR_ID_INTEL, 0x3a3e, NULL);
+       if (!pdev)
+               return;
+       pci_dev_put(pdev);
+       /* System Management Registers. Might be hidden, in which case
+          we can't do the sanity check. But that's OK, because the
+          known-broken BIOSes _don't_ actually hide it, so far. */
+       pdev = pci_get_device(PCI_VENDOR_ID_INTEL, 0x342e, NULL);
+       if (!pdev)
+               return;
+       if (pci_read_config_dword(pdev, 0x188, &vtisochctrl)) {
+               pci_dev_put(pdev);
+               return;
+       }
+       pci_dev_put(pdev);
+       /* If Azalia DMA is routed to the non-isoch DMAR unit, fine. */
+       if (vtisochctrl & 1)
+               return;
+       /* Drop all bits other than the number of TLB entries */
+       vtisochctrl &= 0x1c;
+       /* If we have the recommended number of TLB entries (16), fine. */
+       if (vtisochctrl == 0x10)
+               return;
+       /* Zero TLB entries? You get to ride the short bus to school. */
+       if (!vtisochctrl) {
+               WARN(1, "Your BIOS is broken; DMA routed to ISOCH DMAR unit but no TLB space.\n"
+                    "BIOS vendor: %s; Ver: %s; Product Version: %s\n",
+                    dmi_get_system_info(DMI_BIOS_VENDOR),
+                    dmi_get_system_info(DMI_BIOS_VERSION),
+                    dmi_get_system_info(DMI_PRODUCT_VERSION));
+               iommu_identity_mapping |= IDENTMAP_AZALIA;
+               return;
+       }
+       
+       printk(KERN_WARNING "DMAR: Recommended TLB entries for ISOCH unit is 16; your BIOS set %d\n",
+              vtisochctrl);
+ }
Simple merge
Simple merge
diff --cc kernel/printk.c
Simple merge
diff --cc mm/Kconfig
index 7c5697116fcf86bd4e4c7ad0ee9c42e4f3c04834,011b110365c8681d7b1c546223bdb8a2daccc59d..e338407f1225f0873a8eb20761c86fd82db1dfc0
@@@ -131,12 -131,9 +131,15 @@@ config SPARSEMEM_VMEMMA
  config HAVE_MEMBLOCK
        boolean
  
 +config HAVE_MEMBLOCK_NODE_MAP
 +      boolean
 +
 +config ARCH_DISCARD_MEMBLOCK
 +      boolean
 +
+ config NO_BOOTMEM
+       boolean
  # eventually, we can have this option just 'select SPARSEMEM'
  config MEMORY_HOTPLUG
        bool "Allow for memory hot-add"
diff --cc mm/memblock.c
Simple merge
diff --cc mm/nobootmem.c
Simple merge
diff --cc mm/page_alloc.c
Simple merge