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18068523d3
tmp_suning_uos_patched/include/asm-x86/kvm_host.h
Glauber de Oliveira Costa 18068523d3 KVM: paravirtualized clocksource: host part 
This is the host part of kvm clocksource implementation. As it does
not include clockevents, it is a fairly simple implementation. We
only have to register a per-vcpu area, and start writing to it periodically.

The area is binary compatible with xen, as we use the same shadow_info
structure.

[marcelo: fix bad_page on MSR_KVM_SYSTEM_TIME]
[avi: save full value of the msr, even if enable bit is clear]
[avi: clear previous value of time_page]

Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 11:53:22 +03:00

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#/*
* Kernel-based Virtual Machine driver for Linux
*
* This header defines architecture specific interfaces, x86 version
*
* This work is licensed under the terms of the GNU GPL, version 2. See
* the COPYING file in the top-level directory.
*
*/
#ifndef ASM_KVM_HOST_H
#define ASM_KVM_HOST_H
#include <linux/types.h>
#include <linux/mm.h>
#include <linux/kvm.h>
#include <linux/kvm_para.h>
#include <linux/kvm_types.h>
#include <asm/desc.h>
#define CR3_PAE_RESERVED_BITS ((X86_CR3_PWT | X86_CR3_PCD) - 1)
#define CR3_NONPAE_RESERVED_BITS ((PAGE_SIZE-1) & ~(X86_CR3_PWT | X86_CR3_PCD))
#define CR3_L_MODE_RESERVED_BITS (CR3_NONPAE_RESERVED_BITS | \
0xFFFFFF0000000000ULL)
#define KVM_GUEST_CR0_MASK \
(X86_CR0_PG | X86_CR0_PE | X86_CR0_WP | X86_CR0_NE \
| X86_CR0_NW | X86_CR0_CD)
#define KVM_VM_CR0_ALWAYS_ON \
(X86_CR0_PG | X86_CR0_PE | X86_CR0_WP | X86_CR0_NE | X86_CR0_TS \
| X86_CR0_MP)
#define KVM_GUEST_CR4_MASK \
(X86_CR4_VME | X86_CR4_PSE | X86_CR4_PAE | X86_CR4_PGE | X86_CR4_VMXE)
#define KVM_PMODE_VM_CR4_ALWAYS_ON (X86_CR4_PAE | X86_CR4_VMXE)
#define KVM_RMODE_VM_CR4_ALWAYS_ON (X86_CR4_VME | X86_CR4_PAE | X86_CR4_VMXE)
#define INVALID_PAGE (~(hpa_t)0)
#define UNMAPPED_GVA (~(gpa_t)0)
#define DE_VECTOR 0
#define UD_VECTOR 6
#define NM_VECTOR 7
#define DF_VECTOR 8
#define TS_VECTOR 10
#define NP_VECTOR 11
#define SS_VECTOR 12
#define GP_VECTOR 13
#define PF_VECTOR 14
#define SELECTOR_TI_MASK (1 << 2)
#define SELECTOR_RPL_MASK 0x03
#define IOPL_SHIFT 12
#define KVM_ALIAS_SLOTS 4
#define KVM_PERMILLE_MMU_PAGES 20
#define KVM_MIN_ALLOC_MMU_PAGES 64
#define KVM_MMU_HASH_SHIFT 10
#define KVM_NUM_MMU_PAGES (1 << KVM_MMU_HASH_SHIFT)
#define KVM_MIN_FREE_MMU_PAGES 5
#define KVM_REFILL_PAGES 25
#define KVM_MAX_CPUID_ENTRIES 40
extern spinlock_t kvm_lock;
extern struct list_head vm_list;
struct kvm_vcpu;
struct kvm;
enum {
VCPU_REGS_RAX = 0,
VCPU_REGS_RCX = 1,
VCPU_REGS_RDX = 2,
VCPU_REGS_RBX = 3,
VCPU_REGS_RSP = 4,
VCPU_REGS_RBP = 5,
VCPU_REGS_RSI = 6,
VCPU_REGS_RDI = 7,
#ifdef CONFIG_X86_64
VCPU_REGS_R8 = 8,
VCPU_REGS_R9 = 9,
VCPU_REGS_R10 = 10,
VCPU_REGS_R11 = 11,
VCPU_REGS_R12 = 12,
VCPU_REGS_R13 = 13,
VCPU_REGS_R14 = 14,
VCPU_REGS_R15 = 15,
#endif
NR_VCPU_REGS
};
enum {
VCPU_SREG_CS,
VCPU_SREG_DS,
VCPU_SREG_ES,
VCPU_SREG_FS,
VCPU_SREG_GS,
VCPU_SREG_SS,
VCPU_SREG_TR,
VCPU_SREG_LDTR,
};
#include <asm/kvm_x86_emulate.h>
#define KVM_NR_MEM_OBJS 40
/*
* We don't want allocation failures within the mmu code, so we preallocate
* enough memory for a single page fault in a cache.
*/
struct kvm_mmu_memory_cache {
int nobjs;
void *objects[KVM_NR_MEM_OBJS];
};
#define NR_PTE_CHAIN_ENTRIES 5
struct kvm_pte_chain {
u64 *parent_ptes[NR_PTE_CHAIN_ENTRIES];
struct hlist_node link;
};
/*
* kvm_mmu_page_role, below, is defined as:
*
* bits 0:3 - total guest paging levels (2-4, or zero for real mode)
* bits 4:7 - page table level for this shadow (1-4)
* bits 8:9 - page table quadrant for 2-level guests
* bit 16 - "metaphysical" - gfn is not a real page (huge page/real mode)
* bits 17:19 - common access permissions for all ptes in this shadow page
*/
union kvm_mmu_page_role {
unsigned word;
struct {
unsigned glevels:4;
unsigned level:4;
unsigned quadrant:2;
unsigned pad_for_nice_hex_output:6;
unsigned metaphysical:1;
unsigned access:3;
};
};
struct kvm_mmu_page {
struct list_head link;
struct hlist_node hash_link;
/*
* The following two entries are used to key the shadow page in the
* hash table.
*/
gfn_t gfn;
union kvm_mmu_page_role role;
u64 *spt;
/* hold the gfn of each spte inside spt */
gfn_t *gfns;
unsigned long slot_bitmap; /* One bit set per slot which has memory
* in this shadow page.
*/
int multimapped; /* More than one parent_pte? */
int root_count; /* Currently serving as active root */
union {
u64 *parent_pte; /* !multimapped */
struct hlist_head parent_ptes; /* multimapped, kvm_pte_chain */
};
};
/*
* x86 supports 3 paging modes (4-level 64-bit, 3-level 64-bit, and 2-level
* 32-bit). The kvm_mmu structure abstracts the details of the current mmu
* mode.
*/
struct kvm_mmu {
void (*new_cr3)(struct kvm_vcpu *vcpu);
int (*page_fault)(struct kvm_vcpu *vcpu, gva_t gva, u32 err);
void (*free)(struct kvm_vcpu *vcpu);
gpa_t (*gva_to_gpa)(struct kvm_vcpu *vcpu, gva_t gva);
void (*prefetch_page)(struct kvm_vcpu *vcpu,
struct kvm_mmu_page *page);
hpa_t root_hpa;
int root_level;
int shadow_root_level;
u64 *pae_root;
};
struct kvm_vcpu_arch {
u64 host_tsc;
int interrupt_window_open;
unsigned long irq_summary; /* bit vector: 1 per word in irq_pending */
DECLARE_BITMAP(irq_pending, KVM_NR_INTERRUPTS);
unsigned long regs[NR_VCPU_REGS]; /* for rsp: vcpu_load_rsp_rip() */
unsigned long rip; /* needs vcpu_load_rsp_rip() */
unsigned long cr0;
unsigned long cr2;
unsigned long cr3;
unsigned long cr4;
unsigned long cr8;
u64 pdptrs[4]; /* pae */
u64 shadow_efer;
u64 apic_base;
struct kvm_lapic *apic; /* kernel irqchip context */
#define VCPU_MP_STATE_RUNNABLE 0
#define VCPU_MP_STATE_UNINITIALIZED 1
#define VCPU_MP_STATE_INIT_RECEIVED 2
#define VCPU_MP_STATE_SIPI_RECEIVED 3
#define VCPU_MP_STATE_HALTED 4
int mp_state;
int sipi_vector;
u64 ia32_misc_enable_msr;
bool tpr_access_reporting;
struct kvm_mmu mmu;
struct kvm_mmu_memory_cache mmu_pte_chain_cache;
struct kvm_mmu_memory_cache mmu_rmap_desc_cache;
struct kvm_mmu_memory_cache mmu_page_cache;
struct kvm_mmu_memory_cache mmu_page_header_cache;
gfn_t last_pt_write_gfn;
int last_pt_write_count;
u64 *last_pte_updated;
struct {
gfn_t gfn; /* presumed gfn during guest pte update */
struct page *page; /* page corresponding to that gfn */
} update_pte;
struct i387_fxsave_struct host_fx_image;
struct i387_fxsave_struct guest_fx_image;
gva_t mmio_fault_cr2;
struct kvm_pio_request pio;
void *pio_data;
struct kvm_queued_exception {
bool pending;
bool has_error_code;
u8 nr;
u32 error_code;
} exception;
struct {
int active;
u8 save_iopl;
struct kvm_save_segment {
u16 selector;
unsigned long base;
u32 limit;
u32 ar;
} tr, es, ds, fs, gs;
} rmode;
int halt_request; /* real mode on Intel only */
int cpuid_nent;
struct kvm_cpuid_entry2 cpuid_entries[KVM_MAX_CPUID_ENTRIES];
/* emulate context */
struct x86_emulate_ctxt emulate_ctxt;
gpa_t time;
struct kvm_vcpu_time_info hv_clock;
unsigned int time_offset;
struct page *time_page;
};
struct kvm_mem_alias {
gfn_t base_gfn;
unsigned long npages;
gfn_t target_gfn;
};
struct kvm_arch{
int naliases;
struct kvm_mem_alias aliases[KVM_ALIAS_SLOTS];
unsigned int n_free_mmu_pages;
unsigned int n_requested_mmu_pages;
unsigned int n_alloc_mmu_pages;
struct hlist_head mmu_page_hash[KVM_NUM_MMU_PAGES];
/*
* Hash table of struct kvm_mmu_page.
*/
struct list_head active_mmu_pages;
struct kvm_pic *vpic;
struct kvm_ioapic *vioapic;
int round_robin_prev_vcpu;
unsigned int tss_addr;
struct page *apic_access_page;
gpa_t wall_clock;
};
struct kvm_vm_stat {
u32 mmu_shadow_zapped;
u32 mmu_pte_write;
u32 mmu_pte_updated;
u32 mmu_pde_zapped;
u32 mmu_flooded;
u32 mmu_recycled;
u32 mmu_cache_miss;
u32 remote_tlb_flush;
};
struct kvm_vcpu_stat {
u32 pf_fixed;
u32 pf_guest;
u32 tlb_flush;
u32 invlpg;
u32 exits;
u32 io_exits;
u32 mmio_exits;
u32 signal_exits;
u32 irq_window_exits;
u32 halt_exits;
u32 halt_wakeup;
u32 request_irq_exits;
u32 irq_exits;
u32 host_state_reload;
u32 efer_reload;
u32 fpu_reload;
u32 insn_emulation;
u32 insn_emulation_fail;
};
struct descriptor_table {
u16 limit;
unsigned long base;
} __attribute__((packed));
struct kvm_x86_ops {
int (*cpu_has_kvm_support)(void); /* __init */
int (*disabled_by_bios)(void); /* __init */
void (*hardware_enable)(void *dummy); /* __init */
void (*hardware_disable)(void *dummy);
void (*check_processor_compatibility)(void *rtn);
int (*hardware_setup)(void); /* __init */
void (*hardware_unsetup)(void); /* __exit */
bool (*cpu_has_accelerated_tpr)(void);
/* Create, but do not attach this VCPU */
struct kvm_vcpu *(*vcpu_create)(struct kvm *kvm, unsigned id);
void (*vcpu_free)(struct kvm_vcpu *vcpu);
int (*vcpu_reset)(struct kvm_vcpu *vcpu);
void (*prepare_guest_switch)(struct kvm_vcpu *vcpu);
void (*vcpu_load)(struct kvm_vcpu *vcpu, int cpu);
void (*vcpu_put)(struct kvm_vcpu *vcpu);
void (*vcpu_decache)(struct kvm_vcpu *vcpu);
int (*set_guest_debug)(struct kvm_vcpu *vcpu,
struct kvm_debug_guest *dbg);
void (*guest_debug_pre)(struct kvm_vcpu *vcpu);
int (*get_msr)(struct kvm_vcpu *vcpu, u32 msr_index, u64 *pdata);
int (*set_msr)(struct kvm_vcpu *vcpu, u32 msr_index, u64 data);
u64 (*get_segment_base)(struct kvm_vcpu *vcpu, int seg);
void (*get_segment)(struct kvm_vcpu *vcpu,
struct kvm_segment *var, int seg);
void (*set_segment)(struct kvm_vcpu *vcpu,
struct kvm_segment *var, int seg);
void (*get_cs_db_l_bits)(struct kvm_vcpu *vcpu, int *db, int *l);
void (*decache_cr4_guest_bits)(struct kvm_vcpu *vcpu);
void (*set_cr0)(struct kvm_vcpu *vcpu, unsigned long cr0);
void (*set_cr3)(struct kvm_vcpu *vcpu, unsigned long cr3);
void (*set_cr4)(struct kvm_vcpu *vcpu, unsigned long cr4);
void (*set_efer)(struct kvm_vcpu *vcpu, u64 efer);
void (*get_idt)(struct kvm_vcpu *vcpu, struct descriptor_table *dt);
void (*set_idt)(struct kvm_vcpu *vcpu, struct descriptor_table *dt);
void (*get_gdt)(struct kvm_vcpu *vcpu, struct descriptor_table *dt);
void (*set_gdt)(struct kvm_vcpu *vcpu, struct descriptor_table *dt);
unsigned long (*get_dr)(struct kvm_vcpu *vcpu, int dr);
void (*set_dr)(struct kvm_vcpu *vcpu, int dr, unsigned long value,
int *exception);
void (*cache_regs)(struct kvm_vcpu *vcpu);
void (*decache_regs)(struct kvm_vcpu *vcpu);
unsigned long (*get_rflags)(struct kvm_vcpu *vcpu);
void (*set_rflags)(struct kvm_vcpu *vcpu, unsigned long rflags);
void (*tlb_flush)(struct kvm_vcpu *vcpu);
void (*run)(struct kvm_vcpu *vcpu, struct kvm_run *run);
int (*handle_exit)(struct kvm_run *run, struct kvm_vcpu *vcpu);
void (*skip_emulated_instruction)(struct kvm_vcpu *vcpu);
void (*patch_hypercall)(struct kvm_vcpu *vcpu,
unsigned char *hypercall_addr);
int (*get_irq)(struct kvm_vcpu *vcpu);
void (*set_irq)(struct kvm_vcpu *vcpu, int vec);
void (*queue_exception)(struct kvm_vcpu *vcpu, unsigned nr,
bool has_error_code, u32 error_code);
bool (*exception_injected)(struct kvm_vcpu *vcpu);
void (*inject_pending_irq)(struct kvm_vcpu *vcpu);
void (*inject_pending_vectors)(struct kvm_vcpu *vcpu,
struct kvm_run *run);
int (*set_tss_addr)(struct kvm *kvm, unsigned int addr);
};
extern struct kvm_x86_ops *kvm_x86_ops;
int kvm_mmu_module_init(void);
void kvm_mmu_module_exit(void);
void kvm_mmu_destroy(struct kvm_vcpu *vcpu);
int kvm_mmu_create(struct kvm_vcpu *vcpu);
int kvm_mmu_setup(struct kvm_vcpu *vcpu);
void kvm_mmu_set_nonpresent_ptes(u64 trap_pte, u64 notrap_pte);
int kvm_mmu_reset_context(struct kvm_vcpu *vcpu);
void kvm_mmu_slot_remove_write_access(struct kvm *kvm, int slot);
void kvm_mmu_zap_all(struct kvm *kvm);
unsigned int kvm_mmu_calculate_mmu_pages(struct kvm *kvm);
void kvm_mmu_change_mmu_pages(struct kvm *kvm, unsigned int kvm_nr_mmu_pages);
int load_pdptrs(struct kvm_vcpu *vcpu, unsigned long cr3);
enum emulation_result {
EMULATE_DONE, /* no further processing */
EMULATE_DO_MMIO, /* kvm_run filled with mmio request */
EMULATE_FAIL, /* can't emulate this instruction */
};
#define EMULTYPE_NO_DECODE (1 << 0)
#define EMULTYPE_TRAP_UD (1 << 1)
int emulate_instruction(struct kvm_vcpu *vcpu, struct kvm_run *run,
unsigned long cr2, u16 error_code, int emulation_type);
void kvm_report_emulation_failure(struct kvm_vcpu *cvpu, const char *context);
void realmode_lgdt(struct kvm_vcpu *vcpu, u16 size, unsigned long address);
void realmode_lidt(struct kvm_vcpu *vcpu, u16 size, unsigned long address);
void realmode_lmsw(struct kvm_vcpu *vcpu, unsigned long msw,
unsigned long *rflags);
unsigned long realmode_get_cr(struct kvm_vcpu *vcpu, int cr);
void realmode_set_cr(struct kvm_vcpu *vcpu, int cr, unsigned long value,
unsigned long *rflags);
void kvm_enable_efer_bits(u64);
int kvm_get_msr(struct kvm_vcpu *vcpu, u32 msr_index, u64 *data);
int kvm_set_msr(struct kvm_vcpu *vcpu, u32 msr_index, u64 data);
struct x86_emulate_ctxt;
int kvm_emulate_pio(struct kvm_vcpu *vcpu, struct kvm_run *run, int in,
int size, unsigned port);
int kvm_emulate_pio_string(struct kvm_vcpu *vcpu, struct kvm_run *run, int in,
int size, unsigned long count, int down,
gva_t address, int rep, unsigned port);
void kvm_emulate_cpuid(struct kvm_vcpu *vcpu);
int kvm_emulate_halt(struct kvm_vcpu *vcpu);
int emulate_invlpg(struct kvm_vcpu *vcpu, gva_t address);
int emulate_clts(struct kvm_vcpu *vcpu);
int emulator_get_dr(struct x86_emulate_ctxt *ctxt, int dr,
unsigned long *dest);
int emulator_set_dr(struct x86_emulate_ctxt *ctxt, int dr,
unsigned long value);
void set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0);
void set_cr3(struct kvm_vcpu *vcpu, unsigned long cr0);
void set_cr4(struct kvm_vcpu *vcpu, unsigned long cr0);
void set_cr8(struct kvm_vcpu *vcpu, unsigned long cr0);
unsigned long get_cr8(struct kvm_vcpu *vcpu);
void lmsw(struct kvm_vcpu *vcpu, unsigned long msw);
void kvm_get_cs_db_l_bits(struct kvm_vcpu *vcpu, int *db, int *l);
int kvm_get_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata);
int kvm_set_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 data);
void kvm_queue_exception(struct kvm_vcpu *vcpu, unsigned nr);
void kvm_queue_exception_e(struct kvm_vcpu *vcpu, unsigned nr, u32 error_code);
void kvm_inject_page_fault(struct kvm_vcpu *vcpu, unsigned long cr2,
u32 error_code);
void fx_init(struct kvm_vcpu *vcpu);
int emulator_read_std(unsigned long addr,
void *val,
unsigned int bytes,
struct kvm_vcpu *vcpu);
int emulator_write_emulated(unsigned long addr,
const void *val,
unsigned int bytes,
struct kvm_vcpu *vcpu);
unsigned long segment_base(u16 selector);
void kvm_mmu_flush_tlb(struct kvm_vcpu *vcpu);
void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa,
const u8 *new, int bytes);
int kvm_mmu_unprotect_page_virt(struct kvm_vcpu *vcpu, gva_t gva);
void __kvm_mmu_free_some_pages(struct kvm_vcpu *vcpu);
int kvm_mmu_load(struct kvm_vcpu *vcpu);
void kvm_mmu_unload(struct kvm_vcpu *vcpu);
int kvm_emulate_hypercall(struct kvm_vcpu *vcpu);
int kvm_fix_hypercall(struct kvm_vcpu *vcpu);
int kvm_mmu_page_fault(struct kvm_vcpu *vcpu, gva_t gva, u32 error_code);
void kvm_enable_tdp(void);
int load_pdptrs(struct kvm_vcpu *vcpu, unsigned long cr3);
int complete_pio(struct kvm_vcpu *vcpu);
static inline struct kvm_mmu_page *page_header(hpa_t shadow_page)
{
struct page *page = pfn_to_page(shadow_page >> PAGE_SHIFT);
return (struct kvm_mmu_page *)page_private(page);
}
static inline u16 read_fs(void)
{
u16 seg;
asm("mov %%fs, %0" : "=g"(seg));
return seg;
}
static inline u16 read_gs(void)
{
u16 seg;
asm("mov %%gs, %0" : "=g"(seg));
return seg;
}
static inline u16 read_ldt(void)
{
u16 ldt;
asm("sldt %0" : "=g"(ldt));
return ldt;
}
static inline void load_fs(u16 sel)
{
asm("mov %0, %%fs" : : "rm"(sel));
}
static inline void load_gs(u16 sel)
{
asm("mov %0, %%gs" : : "rm"(sel));
}
#ifndef load_ldt
static inline void load_ldt(u16 sel)
{
asm("lldt %0" : : "rm"(sel));
}
#endif
static inline void get_idt(struct descriptor_table *table)
{
asm("sidt %0" : "=m"(*table));
}
static inline void get_gdt(struct descriptor_table *table)
{
asm("sgdt %0" : "=m"(*table));
}
static inline unsigned long read_tr_base(void)
{
u16 tr;
asm("str %0" : "=g"(tr));
return segment_base(tr);
}
#ifdef CONFIG_X86_64
static inline unsigned long read_msr(unsigned long msr)
{
u64 value;
rdmsrl(msr, value);
return value;
}
#endif
static inline void fx_save(struct i387_fxsave_struct *image)
{
asm("fxsave (%0)":: "r" (image));
}
static inline void fx_restore(struct i387_fxsave_struct *image)
{
asm("fxrstor (%0)":: "r" (image));
}
static inline void fpu_init(void)
{
asm("finit");
}
static inline u32 get_rdx_init_val(void)
{
return 0x600; /* P6 family */
}
static inline void kvm_inject_gp(struct kvm_vcpu *vcpu, u32 error_code)
{
kvm_queue_exception_e(vcpu, GP_VECTOR, error_code);
}
#define ASM_VMX_VMCLEAR_RAX ".byte 0x66, 0x0f, 0xc7, 0x30"
#define ASM_VMX_VMLAUNCH ".byte 0x0f, 0x01, 0xc2"
#define ASM_VMX_VMRESUME ".byte 0x0f, 0x01, 0xc3"
#define ASM_VMX_VMPTRLD_RAX ".byte 0x0f, 0xc7, 0x30"
#define ASM_VMX_VMREAD_RDX_RAX ".byte 0x0f, 0x78, 0xd0"
#define ASM_VMX_VMWRITE_RAX_RDX ".byte 0x0f, 0x79, 0xd0"
#define ASM_VMX_VMWRITE_RSP_RDX ".byte 0x0f, 0x79, 0xd4"
#define ASM_VMX_VMXOFF ".byte 0x0f, 0x01, 0xc4"
#define ASM_VMX_VMXON_RAX ".byte 0xf3, 0x0f, 0xc7, 0x30"
#define ASM_VMX_INVVPID ".byte 0x66, 0x0f, 0x38, 0x81, 0x08"
#define MSR_IA32_TIME_STAMP_COUNTER 0x010
#define TSS_IOPB_BASE_OFFSET 0x66
#define TSS_BASE_SIZE 0x68
#define TSS_IOPB_SIZE (65536 / 8)
#define TSS_REDIRECTION_SIZE (256 / 8)
#define RMODE_TSS_SIZE \
(TSS_BASE_SIZE + TSS_REDIRECTION_SIZE + TSS_IOPB_SIZE + 1)
#endif
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