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/* SPDX-License-Identifier: MIT *//****************************************************************************** * xen.h * * Guest OS interface to Xen. * * Copyright (c) 2004, K A Fraser */ #ifndef __XEN_PUBLIC_XEN_H__#define __XEN_PUBLIC_XEN_H__ #include <asm/xen/interface.h> /* * XEN "SYSTEM CALLS" (a.k.a. HYPERCALLS). */ /* * x86_32: EAX = vector; EBX, ECX, EDX, ESI, EDI = args 1, 2, 3, 4, 5. *         EAX = return value *         (argument registers may be clobbered on return) * x86_64: RAX = vector; RDI, RSI, RDX, R10, R8, R9 = args 1, 2, 3, 4, 5, 6. *         RAX = return value *         (argument registers not clobbered on return; RCX, R11 are) */#define __HYPERVISOR_set_trap_table        0#define __HYPERVISOR_mmu_update            1#define __HYPERVISOR_set_gdt               2#define __HYPERVISOR_stack_switch          3#define __HYPERVISOR_set_callbacks         4#define __HYPERVISOR_fpu_taskswitch        5#define __HYPERVISOR_sched_op_compat       6#define __HYPERVISOR_platform_op           7#define __HYPERVISOR_set_debugreg          8#define __HYPERVISOR_get_debugreg          9#define __HYPERVISOR_update_descriptor    10#define __HYPERVISOR_memory_op            12#define __HYPERVISOR_multicall            13#define __HYPERVISOR_update_va_mapping    14#define __HYPERVISOR_set_timer_op         15#define __HYPERVISOR_event_channel_op_compat 16#define __HYPERVISOR_xen_version          17#define __HYPERVISOR_console_io           18#define __HYPERVISOR_physdev_op_compat    19#define __HYPERVISOR_grant_table_op       20#define __HYPERVISOR_vm_assist            21#define __HYPERVISOR_update_va_mapping_otherdomain 22#define __HYPERVISOR_iret                 23 /* x86 only */#define __HYPERVISOR_vcpu_op              24#define __HYPERVISOR_set_segment_base     25 /* x86/64 only */#define __HYPERVISOR_mmuext_op            26#define __HYPERVISOR_xsm_op               27#define __HYPERVISOR_nmi_op               28#define __HYPERVISOR_sched_op             29#define __HYPERVISOR_callback_op          30#define __HYPERVISOR_xenoprof_op          31#define __HYPERVISOR_event_channel_op     32#define __HYPERVISOR_physdev_op           33#define __HYPERVISOR_hvm_op               34#define __HYPERVISOR_sysctl               35#define __HYPERVISOR_domctl               36#define __HYPERVISOR_kexec_op             37#define __HYPERVISOR_tmem_op              38#define __HYPERVISOR_xc_reserved_op       39 /* reserved for XenClient */#define __HYPERVISOR_xenpmu_op            40#define __HYPERVISOR_dm_op                41 /* Architecture-specific hypercall definitions. */#define __HYPERVISOR_arch_0               48#define __HYPERVISOR_arch_1               49#define __HYPERVISOR_arch_2               50#define __HYPERVISOR_arch_3               51#define __HYPERVISOR_arch_4               52#define __HYPERVISOR_arch_5               53#define __HYPERVISOR_arch_6               54#define __HYPERVISOR_arch_7               55 /* * VIRTUAL INTERRUPTS * * Virtual interrupts that a guest OS may receive from Xen. * In the side comments, 'V.' denotes a per-VCPU VIRQ while 'G.' denotes a * global VIRQ. The former can be bound once per VCPU and cannot be re-bound. * The latter can be allocated only once per guest: they must initially be * allocated to VCPU0 but can subsequently be re-bound. */#define VIRQ_TIMER      0  /* V. Timebase update, and/or requested timeout.  */#define VIRQ_DEBUG      1  /* V. Request guest to dump debug info.           */#define VIRQ_CONSOLE    2  /* G. (DOM0) Bytes received on emergency console. */#define VIRQ_DOM_EXC    3  /* G. (DOM0) Exceptional event for some domain.   */#define VIRQ_TBUF       4  /* G. (DOM0) Trace buffer has records available.  */#define VIRQ_DEBUGGER   6  /* G. (DOM0) A domain has paused for debugging.   */#define VIRQ_XENOPROF   7  /* V. XenOprofile interrupt: new sample available */#define VIRQ_CON_RING   8  /* G. (DOM0) Bytes received on console            */#define VIRQ_PCPU_STATE 9  /* G. (DOM0) PCPU state changed                   */#define VIRQ_MEM_EVENT  10 /* G. (DOM0) A memory event has occured           */#define VIRQ_XC_RESERVED 11 /* G. Reserved for XenClient                     */#define VIRQ_ENOMEM     12 /* G. (DOM0) Low on heap memory       */#define VIRQ_XENPMU     13  /* PMC interrupt                                 */ /* Architecture-specific VIRQ definitions. */#define VIRQ_ARCH_0    16#define VIRQ_ARCH_1    17#define VIRQ_ARCH_2    18#define VIRQ_ARCH_3    19#define VIRQ_ARCH_4    20#define VIRQ_ARCH_5    21#define VIRQ_ARCH_6    22#define VIRQ_ARCH_7    23 #define NR_VIRQS       24 /* * enum neg_errnoval HYPERVISOR_mmu_update(const struct mmu_update reqs[], *                                         unsigned count, unsigned *done_out, *                                         unsigned foreigndom) * @reqs is an array of mmu_update_t structures ((ptr, val) pairs). * @count is the length of the above array. * @pdone is an output parameter indicating number of completed operations * @foreigndom[15:0]: FD, the expected owner of data pages referenced in this *                    hypercall invocation. Can be DOMID_SELF. * @foreigndom[31:16]: PFD, the expected owner of pagetable pages referenced *                     in this hypercall invocation. The value of this field *                     (x) encodes the PFD as follows: *                     x == 0 => PFD == DOMID_SELF *                     x != 0 => PFD == x - 1 * * Sub-commands: ptr[1:0] specifies the appropriate MMU_* command. * ------------- * ptr[1:0] == MMU_NORMAL_PT_UPDATE: * Updates an entry in a page table belonging to PFD. If updating an L1 table, * and the new table entry is valid/present, the mapped frame must belong to * FD. If attempting to map an I/O page then the caller assumes the privilege * of the FD. * FD == DOMID_IO: Permit /only/ I/O mappings, at the priv level of the caller. * FD == DOMID_XEN: Map restricted areas of Xen's heap space. * ptr[:2]  -- Machine address of the page-table entry to modify. * val      -- Value to write. * * There also certain implicit requirements when using this hypercall. The * pages that make up a pagetable must be mapped read-only in the guest. * This prevents uncontrolled guest updates to the pagetable. Xen strictly * enforces this, and will disallow any pagetable update which will end up * mapping pagetable page RW, and will disallow using any writable page as a * pagetable. In practice it means that when constructing a page table for a * process, thread, etc, we MUST be very dilligient in following these rules: *  1). Start with top-level page (PGD or in Xen language: L4). Fill out *      the entries. *  2). Keep on going, filling out the upper (PUD or L3), and middle (PMD *      or L2). *  3). Start filling out the PTE table (L1) with the PTE entries. Once *      done, make sure to set each of those entries to RO (so writeable bit *      is unset). Once that has been completed, set the PMD (L2) for this *      PTE table as RO. *  4). When completed with all of the PMD (L2) entries, and all of them have *      been set to RO, make sure to set RO the PUD (L3). Do the same *      operation on PGD (L4) pagetable entries that have a PUD (L3) entry. *  5). Now before you can use those pages (so setting the cr3), you MUST also *      pin them so that the hypervisor can verify the entries. This is done *      via the HYPERVISOR_mmuext_op(MMUEXT_PIN_L4_TABLE, guest physical frame *      number of the PGD (L4)). And this point the HYPERVISOR_mmuext_op( *      MMUEXT_NEW_BASEPTR, guest physical frame number of the PGD (L4)) can be *      issued. * For 32-bit guests, the L4 is not used (as there is less pagetables), so * instead use L3. * At this point the pagetables can be modified using the MMU_NORMAL_PT_UPDATE * hypercall. Also if so desired the OS can also try to write to the PTE * and be trapped by the hypervisor (as the PTE entry is RO). * * To deallocate the pages, the operations are the reverse of the steps * mentioned above. The argument is MMUEXT_UNPIN_TABLE for all levels and the * pagetable MUST not be in use (meaning that the cr3 is not set to it). * * ptr[1:0] == MMU_MACHPHYS_UPDATE: * Updates an entry in the machine->pseudo-physical mapping table. * ptr[:2]  -- Machine address within the frame whose mapping to modify. *             The frame must belong to the FD, if one is specified. * val      -- Value to write into the mapping entry. * * ptr[1:0] == MMU_PT_UPDATE_PRESERVE_AD: * As MMU_NORMAL_PT_UPDATE above, but A/D bits currently in the PTE are ORed * with those in @val. * * @val is usually the machine frame number along with some attributes. * The attributes by default follow the architecture defined bits. Meaning that * if this is a X86_64 machine and four page table layout is used, the layout * of val is: *  - 63 if set means No execute (NX) *  - 46-13 the machine frame number *  - 12 available for guest *  - 11 available for guest *  - 10 available for guest *  - 9 available for guest *  - 8 global *  - 7 PAT (PSE is disabled, must use hypercall to make 4MB or 2MB pages) *  - 6 dirty *  - 5 accessed *  - 4 page cached disabled *  - 3 page write through *  - 2 userspace accessible *  - 1 writeable *  - 0 present * *  The one bits that does not fit with the default layout is the PAGE_PSE *  also called PAGE_PAT). The MMUEXT_[UN]MARK_SUPER arguments to the *  HYPERVISOR_mmuext_op serve as mechanism to set a pagetable to be 4MB *  (or 2MB) instead of using the PAGE_PSE bit. * *  The reason that the PAGE_PSE (bit 7) is not being utilized is due to Xen *  using it as the Page Attribute Table (PAT) bit - for details on it please *  refer to Intel SDM 10.12. The PAT allows to set the caching attributes of *  pages instead of using MTRRs. * *  The PAT MSR is as follows (it is a 64-bit value, each entry is 8 bits): *                    PAT4                 PAT0 *  +-----+-----+----+----+----+-----+----+----+ *  | UC  | UC- | WC | WB | UC | UC- | WC | WB |  <= Linux *  +-----+-----+----+----+----+-----+----+----+ *  | UC  | UC- | WT | WB | UC | UC- | WT | WB |  <= BIOS (default when machine boots) *  +-----+-----+----+----+----+-----+----+----+ *  | rsv | rsv | WP | WC | UC | UC- | WT | WB |  <= Xen *  +-----+-----+----+----+----+-----+----+----+ * *  The lookup of this index table translates to looking up *  Bit 7, Bit 4, and Bit 3 of val entry: * *  PAT/PSE (bit 7) ... PCD (bit 4) .. PWT (bit 3). * *  If all bits are off, then we are using PAT0. If bit 3 turned on, *  then we are using PAT1, if bit 3 and bit 4, then PAT2.. * *  As you can see, the Linux PAT1 translates to PAT4 under Xen. Which means *  that if a guest that follows Linux's PAT setup and would like to set Write *  Combined on pages it MUST use PAT4 entry. Meaning that Bit 7 (PAGE_PAT) is *  set. For example, under Linux it only uses PAT0, PAT1, and PAT2 for the *  caching as: * *   WB = none (so PAT0) *   WC = PWT (bit 3 on) *   UC = PWT | PCD (bit 3 and 4 are on). * * To make it work with Xen, it needs to translate the WC bit as so: * *  PWT (so bit 3 on) --> PAT (so bit 7 is on) and clear bit 3 * * And to translate back it would: * * PAT (bit 7 on) --> PWT (bit 3 on) and clear bit 7. */#define MMU_NORMAL_PT_UPDATE       0 /* checked '*ptr = val'. ptr is MA.      */#define MMU_MACHPHYS_UPDATE        1 /* ptr = MA of frame to modify entry for */#define MMU_PT_UPDATE_PRESERVE_AD  2 /* atomically: *ptr = val | (*ptr&(A|D)) */#define MMU_PT_UPDATE_NO_TRANSLATE 3 /* checked '*ptr = val'. ptr is MA.      */ /* * MMU EXTENDED OPERATIONS * * enum neg_errnoval HYPERVISOR_mmuext_op(mmuext_op_t uops[], *                                        unsigned int count, *                                        unsigned int *pdone, *                                        unsigned int foreigndom) *//* HYPERVISOR_mmuext_op() accepts a list of mmuext_op structures. * A foreigndom (FD) can be specified (or DOMID_SELF for none). * Where the FD has some effect, it is described below. * * cmd: MMUEXT_(UN)PIN_*_TABLE * mfn: Machine frame number to be (un)pinned as a p.t. page. *      The frame must belong to the FD, if one is specified. * * cmd: MMUEXT_NEW_BASEPTR * mfn: Machine frame number of new page-table base to install in MMU. * * cmd: MMUEXT_NEW_USER_BASEPTR [x86/64 only] * mfn: Machine frame number of new page-table base to install in MMU *      when in user space. * * cmd: MMUEXT_TLB_FLUSH_LOCAL * No additional arguments. Flushes local TLB. * * cmd: MMUEXT_INVLPG_LOCAL * linear_addr: Linear address to be flushed from the local TLB. * * cmd: MMUEXT_TLB_FLUSH_MULTI * vcpumask: Pointer to bitmap of VCPUs to be flushed. * * cmd: MMUEXT_INVLPG_MULTI * linear_addr: Linear address to be flushed. * vcpumask: Pointer to bitmap of VCPUs to be flushed. * * cmd: MMUEXT_TLB_FLUSH_ALL * No additional arguments. Flushes all VCPUs' TLBs. * * cmd: MMUEXT_INVLPG_ALL * linear_addr: Linear address to be flushed from all VCPUs' TLBs. * * cmd: MMUEXT_FLUSH_CACHE * No additional arguments. Writes back and flushes cache contents. * * cmd: MMUEXT_FLUSH_CACHE_GLOBAL * No additional arguments. Writes back and flushes cache contents * on all CPUs in the system. * * cmd: MMUEXT_SET_LDT * linear_addr: Linear address of LDT base (NB. must be page-aligned). * nr_ents: Number of entries in LDT. * * cmd: MMUEXT_CLEAR_PAGE * mfn: Machine frame number to be cleared. * * cmd: MMUEXT_COPY_PAGE * mfn: Machine frame number of the destination page. * src_mfn: Machine frame number of the source page. * * cmd: MMUEXT_[UN]MARK_SUPER * mfn: Machine frame number of head of superpage to be [un]marked. */#define MMUEXT_PIN_L1_TABLE      0#define MMUEXT_PIN_L2_TABLE      1#define MMUEXT_PIN_L3_TABLE      2#define MMUEXT_PIN_L4_TABLE      3#define MMUEXT_UNPIN_TABLE       4#define MMUEXT_NEW_BASEPTR       5#define MMUEXT_TLB_FLUSH_LOCAL   6#define MMUEXT_INVLPG_LOCAL      7#define MMUEXT_TLB_FLUSH_MULTI   8#define MMUEXT_INVLPG_MULTI      9#define MMUEXT_TLB_FLUSH_ALL    10#define MMUEXT_INVLPG_ALL       11#define MMUEXT_FLUSH_CACHE      12#define MMUEXT_SET_LDT          13#define MMUEXT_NEW_USER_BASEPTR 15#define MMUEXT_CLEAR_PAGE       16#define MMUEXT_COPY_PAGE        17#define MMUEXT_FLUSH_CACHE_GLOBAL 18#define MMUEXT_MARK_SUPER       19#define MMUEXT_UNMARK_SUPER     20 #ifndef __ASSEMBLER__struct mmuext_op {	unsigned int cmd;	union {		/* [UN]PIN_TABLE, NEW_BASEPTR, NEW_USER_BASEPTR		 * CLEAR_PAGE, COPY_PAGE, [UN]MARK_SUPER */		xen_pfn_t mfn;		/* INVLPG_LOCAL, INVLPG_ALL, SET_LDT */		unsigned long linear_addr;	} arg1;	union {		/* SET_LDT */		unsigned int nr_ents;		/* TLB_FLUSH_MULTI, INVLPG_MULTI */		void *vcpumask;		/* COPY_PAGE */		xen_pfn_t src_mfn;	} arg2;};DEFINE_GUEST_HANDLE_STRUCT(mmuext_op);#endif /* These are passed as 'flags' to update_va_mapping. They can be ORed. *//* When specifying UVMF_MULTI, also OR in a pointer to a CPU bitmap.   *//* UVMF_LOCAL is merely UVMF_MULTI with a NULL bitmap pointer.         */#define UVMF_NONE               (0UL<<0) /* No flushing at all.   */#define UVMF_TLB_FLUSH          (1UL<<0) /* Flush entire TLB(s).  */#define UVMF_INVLPG             (2UL<<0) /* Flush only one entry. */#define UVMF_FLUSHTYPE_MASK     (3UL<<0)#define UVMF_MULTI              (0UL<<2) /* Flush subset of TLBs. */#define UVMF_LOCAL              (0UL<<2) /* Flush local TLB.      */#define UVMF_ALL                (1UL<<2) /* Flush all TLBs.       */ /* * Commands to HYPERVISOR_console_io(). */#define CONSOLEIO_write         0#define CONSOLEIO_read          1 /* * Commands to HYPERVISOR_vm_assist(). */#define VMASST_CMD_enable                0#define VMASST_CMD_disable               1 /* x86/32 guests: simulate full 4GB segment limits. */#define VMASST_TYPE_4gb_segments         0 /* x86/32 guests: trap (vector 15) whenever above vmassist is used. */#define VMASST_TYPE_4gb_segments_notify  1 /* * x86 guests: support writes to bottom-level PTEs. * NB1. Page-directory entries cannot be written. * NB2. Guest must continue to remove all writable mappings of PTEs. */#define VMASST_TYPE_writable_pagetables  2 /* x86/PAE guests: support PDPTs above 4GB. */#define VMASST_TYPE_pae_extended_cr3     3 /* * x86 guests: Sane behaviour for virtual iopl *  - virtual iopl updated from do_iret() hypercalls. *  - virtual iopl reported in bounce frames. *  - guest kernels assumed to be level 0 for the purpose of iopl checks. */#define VMASST_TYPE_architectural_iopl   4 /* * All guests: activate update indicator in vcpu_runstate_info * Enable setting the XEN_RUNSTATE_UPDATE flag in guest memory mapped * vcpu_runstate_info during updates of the runstate information. */#define VMASST_TYPE_runstate_update_flag 5 #define MAX_VMASST_TYPE 5 #ifndef __ASSEMBLER__ typedef uint16_t domid_t; /* Domain ids >= DOMID_FIRST_RESERVED cannot be used for ordinary domains. */#define DOMID_FIRST_RESERVED (0x7FF0U) /* DOMID_SELF is used in certain contexts to refer to oneself. */#define DOMID_SELF (0x7FF0U) /* * DOMID_IO is used to restrict page-table updates to mapping I/O memory. * Although no Foreign Domain need be specified to map I/O pages, DOMID_IO * is useful to ensure that no mappings to the OS's own heap are accidentally * installed. (e.g., in Linux this could cause havoc as reference counts * aren't adjusted on the I/O-mapping code path). * This only makes sense in MMUEXT_SET_FOREIGNDOM, but in that context can * be specified by any calling domain. */#define DOMID_IO   (0x7FF1U) /* * DOMID_XEN is used to allow privileged domains to map restricted parts of * Xen's heap space (e.g., the machine_to_phys table). * This only makes sense in MMUEXT_SET_FOREIGNDOM, and is only permitted if * the caller is privileged. */#define DOMID_XEN  (0x7FF2U) /* DOMID_COW is used as the owner of sharable pages */#define DOMID_COW  (0x7FF3U) /* DOMID_INVALID is used to identify pages with unknown owner. */#define DOMID_INVALID (0x7FF4U) /* Idle domain. */#define DOMID_IDLE (0x7FFFU) /* * Send an array of these to HYPERVISOR_mmu_update(). * NB. The fields are natural pointer/address size for this architecture. */struct mmu_update {    uint64_t ptr;       /* Machine address of PTE. */    uint64_t val;       /* New contents of PTE.    */};DEFINE_GUEST_HANDLE_STRUCT(mmu_update); /* * Send an array of these to HYPERVISOR_multicall(). * NB. The fields are logically the natural register size for this * architecture. In cases where xen_ulong_t is larger than this then * any unused bits in the upper portion must be zero. */struct multicall_entry {    xen_ulong_t op;    xen_long_t result;    xen_ulong_t args[6];};DEFINE_GUEST_HANDLE_STRUCT(multicall_entry); struct vcpu_time_info {	/*	 * Updates to the following values are preceded and followed	 * by an increment of 'version'. The guest can therefore	 * detect updates by looking for changes to 'version'. If the	 * least-significant bit of the version number is set then an	 * update is in progress and the guest must wait to read a	 * consistent set of values.  The correct way to interact with	 * the version number is similar to Linux's seqlock: see the	 * implementations of read_seqbegin/read_seqretry.	 */	uint32_t version;	uint32_t pad0;	uint64_t tsc_timestamp;   /* TSC at last update of time vals.  */	uint64_t system_time;     /* Time, in nanosecs, since boot.    */	/*	 * Current system time:	 *   system_time + ((tsc - tsc_timestamp) << tsc_shift) * tsc_to_system_mul	 * CPU frequency (Hz):	 *   ((10^9 << 32) / tsc_to_system_mul) >> tsc_shift	 */	uint32_t tsc_to_system_mul;

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