/****************************************************************************** * xen.h * * Guest OS interface to Xen. * * Copyright (c) 2004, K A Fraser */ #ifndef __XEN_PUBLIC_XEN_H__ #define __XEN_PUBLIC_XEN_H__ #include /* * 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 6 #define __HYPERVISOR_dom0_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_acm_op 27 #define __HYPERVISOR_nmi_op 28 #define __HYPERVISOR_sched_op_new 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 /* 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. */ #define VIRQ_TIMER 0 /* Timebase update, and/or requested timeout. */ #define VIRQ_DEBUG 1 /* Request guest to dump debug info. */ #define VIRQ_CONSOLE 2 /* (DOM0) Bytes received on emergency console. */ #define VIRQ_DOM_EXC 3 /* (DOM0) Exceptional event for some domain. */ #define VIRQ_DEBUGGER 6 /* (DOM0) A domain has paused for debugging. */ #define NR_VIRQS 8 /* * MMU-UPDATE REQUESTS * * HYPERVISOR_mmu_update() accepts a list of (ptr, val) pairs. * A foreigndom (FD) can be specified (or DOMID_SELF for none). * Where the FD has some effect, it is described below. * ptr[1:0] specifies the appropriate MMU_* command. * * ptr[1:0] == MMU_NORMAL_PT_UPDATE: * Updates an entry in a page table. If updating an L1 table, and the new * table entry is valid/present, the mapped frame must belong to the FD, if * an FD has been specified. 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. * * 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. */ #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 */ /* * MMU EXTENDED OPERATIONS * * 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_SET_LDT * linear_addr: Linear address of LDT base (NB. must be page-aligned). * nr_ents: Number of entries in LDT. */ #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 #ifndef __ASSEMBLY__ struct mmuext_op { unsigned int cmd; union { /* [UN]PIN_TABLE, NEW_BASEPTR, NEW_USER_BASEPTR */ unsigned long 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; } 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 #define VMASST_TYPE_4gb_segments 0 #define VMASST_TYPE_4gb_segments_notify 1 #define VMASST_TYPE_writable_pagetables 2 #define VMASST_TYPE_pae_extended_cr3 3 #define MAX_VMASST_TYPE 3 #ifndef __ASSEMBLY__ 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) /* * 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 natural register size for this architecture. */ struct multicall_entry { unsigned long op; long result; unsigned long args[6]; }; DEFINE_GUEST_HANDLE_STRUCT(multicall_entry); /* * Event channel endpoints per domain: * 1024 if a long is 32 bits; 4096 if a long is 64 bits. */ #define NR_EVENT_CHANNELS (sizeof(unsigned long) * sizeof(unsigned long) * 64) 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; int8_t tsc_shift; int8_t pad1[3]; }; /* 32 bytes */ struct vcpu_info { /* * 'evtchn_upcall_pending' is written non-zero by Xen to indicate * a pending notification for a particular VCPU. It is then cleared * by the guest OS /before/ checking for pending work, thus avoiding * a set-and-check race. Note that the mask is only accessed by Xen * on the CPU that is currently hosting the VCPU. This means that the * pending and mask flags can be updated by the guest without special * synchronisation (i.e., no need for the x86 LOCK prefix). * This may seem suboptimal because if the pending flag is set by * a different CPU then an IPI may be scheduled even when the mask * is set. However, note: * 1. The task of 'interrupt holdoff' is covered by the per-event- * channel mask bits. A 'noisy' event that is continually being * triggered can be masked at source at this very precise * granularity. * 2. The main purpose of the per-VCPU mask is therefore to restrict * reentrant execution: whether for concurrency control, or to * prevent unbounded stack usage. Whatever the purpose, we expect * that the mask will be asserted only for short periods at a time, * and so the likelihood of a 'spurious' IPI is suitably small. * The mask is read before making an event upcall to the guest: a * non-zero mask therefore guarantees that the VCPU will not receive * an upcall activation. The mask is cleared when the VCPU requests * to block: this avoids wakeup-waiting races. */ uint8_t evtchn_upcall_pending; uint8_t evtchn_upcall_mask; unsigned long evtchn_pending_sel; struct arch_vcpu_info arch; struct vcpu_time_info time; }; /* 64 bytes (x86) */ /* * Xen/kernel shared data -- pointer provided in start_info. * NB. We expect that this struct is smaller than a page. */ struct shared_info { struct vcpu_info vcpu_info[MAX_VIRT_CPUS]; /* * A domain can create "event channels" on which it can send and receive * asynchronous event notifications. There are three classes of event that * are delivered by this mechanism: * 1. Bi-directional inter- and intra-domain connections. Domains must * arrange out-of-band to set up a connection (usually by allocating * an unbound 'listener' port and avertising that via a storage service * such as xenstore). * 2. Physical interrupts. A domain with suitable hardware-access * privileges can bind an event-channel port to a physical interrupt * source. * 3. Virtual interrupts ('events'). A domain can bind an event-channel * port to a virtual interrupt source, such as the virtual-timer * device or the emergency console. * * Event channels are addressed by a "port index". Each channel is * associated with two bits of information: * 1. PENDING -- notifies the domain that there is a pending notification * to be processed. This bit is cleared by the guest. * 2. MASK -- if this bit is clear then a 0->1 transition of PENDING * will cause an asynchronous upcall to be scheduled. This bit is only * updated by the guest. It is read-only within Xen. If a channel * becomes pending while the channel is masked then the 'edge' is lost * (i.e., when the channel is unmasked, the guest must manually handle * pending notifications as no upcall will be scheduled by Xen). * * To expedite scanning of pending notifications, any 0->1 pending * transition on an unmasked channel causes a corresponding bit in a * per-vcpu selector word to be set. Each bit in the selector covers a * 'C long' in the PENDING bitfield array. */ unsigned long evtchn_pending[sizeof(unsigned long) * 8]; unsigned long evtchn_mask[sizeof(unsigned long) * 8]; /* * Wallclock time: updated only by control software. Guests should base * their gettimeofday() syscall on this wallclock-base value. */ uint32_t wc_version; /* Version counter: see vcpu_time_info_t. */ uint32_t wc_sec; /* Secs 00:00:00 UTC, Jan 1, 1970. */ uint32_t wc_nsec; /* Nsecs 00:00:00 UTC, Jan 1, 1970. */ struct arch_shared_info arch; }; /* * Start-of-day memory layout for the initial domain (DOM0): * 1. The domain is started within contiguous virtual-memory region. * 2. The contiguous region begins and ends on an aligned 4MB boundary. * 3. The region start corresponds to the load address of the OS image. * If the load address is not 4MB aligned then the address is rounded down. * 4. This the order of bootstrap elements in the initial virtual region: * a. relocated kernel image * b. initial ram disk [mod_start, mod_len] * c. list of allocated page frames [mfn_list, nr_pages] * d. start_info_t structure [register ESI (x86)] * e. bootstrap page tables [pt_base, CR3 (x86)] * f. bootstrap stack [register ESP (x86)] * 5. Bootstrap elements are packed together, but each is 4kB-aligned. * 6. The initial ram disk may be omitted. * 7. The list of page frames forms a contiguous 'pseudo-physical' memory * layout for the domain. In particular, the bootstrap virtual-memory * region is a 1:1 mapping to the first section of the pseudo-physical map. * 8. All bootstrap elements are mapped read-writable for the guest OS. The * only exception is the bootstrap page table, which is mapped read-only. * 9. There is guaranteed to be at least 512kB padding after the final * bootstrap element. If necessary, the bootstrap virtual region is * extended by an extra 4MB to ensure this. */ #define MAX_GUEST_CMDLINE 1024 struct start_info { /* THE FOLLOWING ARE FILLED IN BOTH ON INITIAL BOOT AND ON RESUME. */ char magic[32]; /* "xen--". */ unsigned long nr_pages; /* Total pages allocated to this domain. */ unsigned long shared_info; /* MACHINE address of shared info struct. */ uint32_t flags; /* SIF_xxx flags. */ unsigned long store_mfn; /* MACHINE page number of shared page. */ uint32_t store_evtchn; /* Event channel for store communication. */ union { struct { unsigned long mfn; /* MACHINE page number of console page. */ uint32_t evtchn; /* Event channel for console page. */ } domU; struct { uint32_t info_off; /* Offset of console_info struct. */ uint32_t info_size; /* Size of console_info struct from start.*/ } dom0; } console; /* THE FOLLOWING ARE ONLY FILLED IN ON INITIAL BOOT (NOT RESUME). */ unsigned long pt_base; /* VIRTUAL address of page directory. */ unsigned long nr_pt_frames; /* Number of bootstrap p.t. frames. */ unsigned long mfn_list; /* VIRTUAL address of page-frame list. */ unsigned long mod_start; /* VIRTUAL address of pre-loaded module. */ unsigned long mod_len; /* Size (bytes) of pre-loaded module. */ int8_t cmd_line[MAX_GUEST_CMDLINE]; }; /* These flags are passed in the 'flags' field of start_info_t. */ #define SIF_PRIVILEGED (1<<0) /* Is the domain privileged? */ #define SIF_INITDOMAIN (1<<1) /* Is this the initial control domain? */ typedef uint64_t cpumap_t; typedef uint8_t xen_domain_handle_t[16]; /* Turn a plain number into a C unsigned long constant. */ #define __mk_unsigned_long(x) x ## UL #define mk_unsigned_long(x) __mk_unsigned_long(x) #else /* __ASSEMBLY__ */ /* In assembly code we cannot use C numeric constant suffixes. */ #define mk_unsigned_long(x) x #endif /* !__ASSEMBLY__ */ #endif /* __XEN_PUBLIC_XEN_H__ */