1 /****************************************************************************** 2 * xen.h 3 * 4 * Guest OS interface to Xen. 5 * 6 * Copyright (c) 2004, K A Fraser 7 */ 8 9 #ifndef __XEN_PUBLIC_XEN_H__ 10 #define __XEN_PUBLIC_XEN_H__ 11 12 #include <asm/xen/interface.h> 13 14 /* 15 * XEN "SYSTEM CALLS" (a.k.a. HYPERCALLS). 16 */ 17 18 /* 19 * x86_32: EAX = vector; EBX, ECX, EDX, ESI, EDI = args 1, 2, 3, 4, 5. 20 * EAX = return value 21 * (argument registers may be clobbered on return) 22 * x86_64: RAX = vector; RDI, RSI, RDX, R10, R8, R9 = args 1, 2, 3, 4, 5, 6. 23 * RAX = return value 24 * (argument registers not clobbered on return; RCX, R11 are) 25 */ 26 #define __HYPERVISOR_set_trap_table 0 27 #define __HYPERVISOR_mmu_update 1 28 #define __HYPERVISOR_set_gdt 2 29 #define __HYPERVISOR_stack_switch 3 30 #define __HYPERVISOR_set_callbacks 4 31 #define __HYPERVISOR_fpu_taskswitch 5 32 #define __HYPERVISOR_sched_op 6 33 #define __HYPERVISOR_dom0_op 7 34 #define __HYPERVISOR_set_debugreg 8 35 #define __HYPERVISOR_get_debugreg 9 36 #define __HYPERVISOR_update_descriptor 10 37 #define __HYPERVISOR_memory_op 12 38 #define __HYPERVISOR_multicall 13 39 #define __HYPERVISOR_update_va_mapping 14 40 #define __HYPERVISOR_set_timer_op 15 41 #define __HYPERVISOR_event_channel_op_compat 16 42 #define __HYPERVISOR_xen_version 17 43 #define __HYPERVISOR_console_io 18 44 #define __HYPERVISOR_physdev_op_compat 19 45 #define __HYPERVISOR_grant_table_op 20 46 #define __HYPERVISOR_vm_assist 21 47 #define __HYPERVISOR_update_va_mapping_otherdomain 22 48 #define __HYPERVISOR_iret 23 /* x86 only */ 49 #define __HYPERVISOR_vcpu_op 24 50 #define __HYPERVISOR_set_segment_base 25 /* x86/64 only */ 51 #define __HYPERVISOR_mmuext_op 26 52 #define __HYPERVISOR_acm_op 27 53 #define __HYPERVISOR_nmi_op 28 54 #define __HYPERVISOR_sched_op_new 29 55 #define __HYPERVISOR_callback_op 30 56 #define __HYPERVISOR_xenoprof_op 31 57 #define __HYPERVISOR_event_channel_op 32 58 #define __HYPERVISOR_physdev_op 33 59 #define __HYPERVISOR_hvm_op 34 60 61 /* 62 * VIRTUAL INTERRUPTS 63 * 64 * Virtual interrupts that a guest OS may receive from Xen. 65 */ 66 #define VIRQ_TIMER 0 /* Timebase update, and/or requested timeout. */ 67 #define VIRQ_DEBUG 1 /* Request guest to dump debug info. */ 68 #define VIRQ_CONSOLE 2 /* (DOM0) Bytes received on emergency console. */ 69 #define VIRQ_DOM_EXC 3 /* (DOM0) Exceptional event for some domain. */ 70 #define VIRQ_DEBUGGER 6 /* (DOM0) A domain has paused for debugging. */ 71 #define NR_VIRQS 8 72 73 /* 74 * MMU-UPDATE REQUESTS 75 * 76 * HYPERVISOR_mmu_update() accepts a list of (ptr, val) pairs. 77 * A foreigndom (FD) can be specified (or DOMID_SELF for none). 78 * Where the FD has some effect, it is described below. 79 * ptr[1:0] specifies the appropriate MMU_* command. 80 * 81 * ptr[1:0] == MMU_NORMAL_PT_UPDATE: 82 * Updates an entry in a page table. If updating an L1 table, and the new 83 * table entry is valid/present, the mapped frame must belong to the FD, if 84 * an FD has been specified. If attempting to map an I/O page then the 85 * caller assumes the privilege of the FD. 86 * FD == DOMID_IO: Permit /only/ I/O mappings, at the priv level of the caller. 87 * FD == DOMID_XEN: Map restricted areas of Xen's heap space. 88 * ptr[:2] -- Machine address of the page-table entry to modify. 89 * val -- Value to write. 90 * 91 * ptr[1:0] == MMU_MACHPHYS_UPDATE: 92 * Updates an entry in the machine->pseudo-physical mapping table. 93 * ptr[:2] -- Machine address within the frame whose mapping to modify. 94 * The frame must belong to the FD, if one is specified. 95 * val -- Value to write into the mapping entry. 96 */ 97 #define MMU_NORMAL_PT_UPDATE 0 /* checked '*ptr = val'. ptr is MA. */ 98 #define MMU_MACHPHYS_UPDATE 1 /* ptr = MA of frame to modify entry for */ 99 100 /* 101 * MMU EXTENDED OPERATIONS 102 * 103 * HYPERVISOR_mmuext_op() accepts a list of mmuext_op structures. 104 * A foreigndom (FD) can be specified (or DOMID_SELF for none). 105 * Where the FD has some effect, it is described below. 106 * 107 * cmd: MMUEXT_(UN)PIN_*_TABLE 108 * mfn: Machine frame number to be (un)pinned as a p.t. page. 109 * The frame must belong to the FD, if one is specified. 110 * 111 * cmd: MMUEXT_NEW_BASEPTR 112 * mfn: Machine frame number of new page-table base to install in MMU. 113 * 114 * cmd: MMUEXT_NEW_USER_BASEPTR [x86/64 only] 115 * mfn: Machine frame number of new page-table base to install in MMU 116 * when in user space. 117 * 118 * cmd: MMUEXT_TLB_FLUSH_LOCAL 119 * No additional arguments. Flushes local TLB. 120 * 121 * cmd: MMUEXT_INVLPG_LOCAL 122 * linear_addr: Linear address to be flushed from the local TLB. 123 * 124 * cmd: MMUEXT_TLB_FLUSH_MULTI 125 * vcpumask: Pointer to bitmap of VCPUs to be flushed. 126 * 127 * cmd: MMUEXT_INVLPG_MULTI 128 * linear_addr: Linear address to be flushed. 129 * vcpumask: Pointer to bitmap of VCPUs to be flushed. 130 * 131 * cmd: MMUEXT_TLB_FLUSH_ALL 132 * No additional arguments. Flushes all VCPUs' TLBs. 133 * 134 * cmd: MMUEXT_INVLPG_ALL 135 * linear_addr: Linear address to be flushed from all VCPUs' TLBs. 136 * 137 * cmd: MMUEXT_FLUSH_CACHE 138 * No additional arguments. Writes back and flushes cache contents. 139 * 140 * cmd: MMUEXT_SET_LDT 141 * linear_addr: Linear address of LDT base (NB. must be page-aligned). 142 * nr_ents: Number of entries in LDT. 143 */ 144 #define MMUEXT_PIN_L1_TABLE 0 145 #define MMUEXT_PIN_L2_TABLE 1 146 #define MMUEXT_PIN_L3_TABLE 2 147 #define MMUEXT_PIN_L4_TABLE 3 148 #define MMUEXT_UNPIN_TABLE 4 149 #define MMUEXT_NEW_BASEPTR 5 150 #define MMUEXT_TLB_FLUSH_LOCAL 6 151 #define MMUEXT_INVLPG_LOCAL 7 152 #define MMUEXT_TLB_FLUSH_MULTI 8 153 #define MMUEXT_INVLPG_MULTI 9 154 #define MMUEXT_TLB_FLUSH_ALL 10 155 #define MMUEXT_INVLPG_ALL 11 156 #define MMUEXT_FLUSH_CACHE 12 157 #define MMUEXT_SET_LDT 13 158 #define MMUEXT_NEW_USER_BASEPTR 15 159 160 #ifndef __ASSEMBLY__ 161 struct mmuext_op { 162 unsigned int cmd; 163 union { 164 /* [UN]PIN_TABLE, NEW_BASEPTR, NEW_USER_BASEPTR */ 165 unsigned long mfn; 166 /* INVLPG_LOCAL, INVLPG_ALL, SET_LDT */ 167 unsigned long linear_addr; 168 } arg1; 169 union { 170 /* SET_LDT */ 171 unsigned int nr_ents; 172 /* TLB_FLUSH_MULTI, INVLPG_MULTI */ 173 void *vcpumask; 174 } arg2; 175 }; 176 DEFINE_GUEST_HANDLE_STRUCT(mmuext_op); 177 #endif 178 179 /* These are passed as 'flags' to update_va_mapping. They can be ORed. */ 180 /* When specifying UVMF_MULTI, also OR in a pointer to a CPU bitmap. */ 181 /* UVMF_LOCAL is merely UVMF_MULTI with a NULL bitmap pointer. */ 182 #define UVMF_NONE (0UL<<0) /* No flushing at all. */ 183 #define UVMF_TLB_FLUSH (1UL<<0) /* Flush entire TLB(s). */ 184 #define UVMF_INVLPG (2UL<<0) /* Flush only one entry. */ 185 #define UVMF_FLUSHTYPE_MASK (3UL<<0) 186 #define UVMF_MULTI (0UL<<2) /* Flush subset of TLBs. */ 187 #define UVMF_LOCAL (0UL<<2) /* Flush local TLB. */ 188 #define UVMF_ALL (1UL<<2) /* Flush all TLBs. */ 189 190 /* 191 * Commands to HYPERVISOR_console_io(). 192 */ 193 #define CONSOLEIO_write 0 194 #define CONSOLEIO_read 1 195 196 /* 197 * Commands to HYPERVISOR_vm_assist(). 198 */ 199 #define VMASST_CMD_enable 0 200 #define VMASST_CMD_disable 1 201 #define VMASST_TYPE_4gb_segments 0 202 #define VMASST_TYPE_4gb_segments_notify 1 203 #define VMASST_TYPE_writable_pagetables 2 204 #define VMASST_TYPE_pae_extended_cr3 3 205 #define MAX_VMASST_TYPE 3 206 207 #ifndef __ASSEMBLY__ 208 209 typedef uint16_t domid_t; 210 211 /* Domain ids >= DOMID_FIRST_RESERVED cannot be used for ordinary domains. */ 212 #define DOMID_FIRST_RESERVED (0x7FF0U) 213 214 /* DOMID_SELF is used in certain contexts to refer to oneself. */ 215 #define DOMID_SELF (0x7FF0U) 216 217 /* 218 * DOMID_IO is used to restrict page-table updates to mapping I/O memory. 219 * Although no Foreign Domain need be specified to map I/O pages, DOMID_IO 220 * is useful to ensure that no mappings to the OS's own heap are accidentally 221 * installed. (e.g., in Linux this could cause havoc as reference counts 222 * aren't adjusted on the I/O-mapping code path). 223 * This only makes sense in MMUEXT_SET_FOREIGNDOM, but in that context can 224 * be specified by any calling domain. 225 */ 226 #define DOMID_IO (0x7FF1U) 227 228 /* 229 * DOMID_XEN is used to allow privileged domains to map restricted parts of 230 * Xen's heap space (e.g., the machine_to_phys table). 231 * This only makes sense in MMUEXT_SET_FOREIGNDOM, and is only permitted if 232 * the caller is privileged. 233 */ 234 #define DOMID_XEN (0x7FF2U) 235 236 /* 237 * Send an array of these to HYPERVISOR_mmu_update(). 238 * NB. The fields are natural pointer/address size for this architecture. 239 */ 240 struct mmu_update { 241 uint64_t ptr; /* Machine address of PTE. */ 242 uint64_t val; /* New contents of PTE. */ 243 }; 244 DEFINE_GUEST_HANDLE_STRUCT(mmu_update); 245 246 /* 247 * Send an array of these to HYPERVISOR_multicall(). 248 * NB. The fields are natural register size for this architecture. 249 */ 250 struct multicall_entry { 251 unsigned long op; 252 long result; 253 unsigned long args[6]; 254 }; 255 DEFINE_GUEST_HANDLE_STRUCT(multicall_entry); 256 257 /* 258 * Event channel endpoints per domain: 259 * 1024 if a long is 32 bits; 4096 if a long is 64 bits. 260 */ 261 #define NR_EVENT_CHANNELS (sizeof(unsigned long) * sizeof(unsigned long) * 64) 262 263 struct vcpu_time_info { 264 /* 265 * Updates to the following values are preceded and followed 266 * by an increment of 'version'. The guest can therefore 267 * detect updates by looking for changes to 'version'. If the 268 * least-significant bit of the version number is set then an 269 * update is in progress and the guest must wait to read a 270 * consistent set of values. The correct way to interact with 271 * the version number is similar to Linux's seqlock: see the 272 * implementations of read_seqbegin/read_seqretry. 273 */ 274 uint32_t version; 275 uint32_t pad0; 276 uint64_t tsc_timestamp; /* TSC at last update of time vals. */ 277 uint64_t system_time; /* Time, in nanosecs, since boot. */ 278 /* 279 * Current system time: 280 * system_time + ((tsc - tsc_timestamp) << tsc_shift) * tsc_to_system_mul 281 * CPU frequency (Hz): 282 * ((10^9 << 32) / tsc_to_system_mul) >> tsc_shift 283 */ 284 uint32_t tsc_to_system_mul; 285 int8_t tsc_shift; 286 int8_t pad1[3]; 287 }; /* 32 bytes */ 288 289 struct vcpu_info { 290 /* 291 * 'evtchn_upcall_pending' is written non-zero by Xen to indicate 292 * a pending notification for a particular VCPU. It is then cleared 293 * by the guest OS /before/ checking for pending work, thus avoiding 294 * a set-and-check race. Note that the mask is only accessed by Xen 295 * on the CPU that is currently hosting the VCPU. This means that the 296 * pending and mask flags can be updated by the guest without special 297 * synchronisation (i.e., no need for the x86 LOCK prefix). 298 * This may seem suboptimal because if the pending flag is set by 299 * a different CPU then an IPI may be scheduled even when the mask 300 * is set. However, note: 301 * 1. The task of 'interrupt holdoff' is covered by the per-event- 302 * channel mask bits. A 'noisy' event that is continually being 303 * triggered can be masked at source at this very precise 304 * granularity. 305 * 2. The main purpose of the per-VCPU mask is therefore to restrict 306 * reentrant execution: whether for concurrency control, or to 307 * prevent unbounded stack usage. Whatever the purpose, we expect 308 * that the mask will be asserted only for short periods at a time, 309 * and so the likelihood of a 'spurious' IPI is suitably small. 310 * The mask is read before making an event upcall to the guest: a 311 * non-zero mask therefore guarantees that the VCPU will not receive 312 * an upcall activation. The mask is cleared when the VCPU requests 313 * to block: this avoids wakeup-waiting races. 314 */ 315 uint8_t evtchn_upcall_pending; 316 uint8_t evtchn_upcall_mask; 317 unsigned long evtchn_pending_sel; 318 struct arch_vcpu_info arch; 319 struct vcpu_time_info time; 320 }; /* 64 bytes (x86) */ 321 322 /* 323 * Xen/kernel shared data -- pointer provided in start_info. 324 * NB. We expect that this struct is smaller than a page. 325 */ 326 struct shared_info { 327 struct vcpu_info vcpu_info[MAX_VIRT_CPUS]; 328 329 /* 330 * A domain can create "event channels" on which it can send and receive 331 * asynchronous event notifications. There are three classes of event that 332 * are delivered by this mechanism: 333 * 1. Bi-directional inter- and intra-domain connections. Domains must 334 * arrange out-of-band to set up a connection (usually by allocating 335 * an unbound 'listener' port and avertising that via a storage service 336 * such as xenstore). 337 * 2. Physical interrupts. A domain with suitable hardware-access 338 * privileges can bind an event-channel port to a physical interrupt 339 * source. 340 * 3. Virtual interrupts ('events'). A domain can bind an event-channel 341 * port to a virtual interrupt source, such as the virtual-timer 342 * device or the emergency console. 343 * 344 * Event channels are addressed by a "port index". Each channel is 345 * associated with two bits of information: 346 * 1. PENDING -- notifies the domain that there is a pending notification 347 * to be processed. This bit is cleared by the guest. 348 * 2. MASK -- if this bit is clear then a 0->1 transition of PENDING 349 * will cause an asynchronous upcall to be scheduled. This bit is only 350 * updated by the guest. It is read-only within Xen. If a channel 351 * becomes pending while the channel is masked then the 'edge' is lost 352 * (i.e., when the channel is unmasked, the guest must manually handle 353 * pending notifications as no upcall will be scheduled by Xen). 354 * 355 * To expedite scanning of pending notifications, any 0->1 pending 356 * transition on an unmasked channel causes a corresponding bit in a 357 * per-vcpu selector word to be set. Each bit in the selector covers a 358 * 'C long' in the PENDING bitfield array. 359 */ 360 unsigned long evtchn_pending[sizeof(unsigned long) * 8]; 361 unsigned long evtchn_mask[sizeof(unsigned long) * 8]; 362 363 /* 364 * Wallclock time: updated only by control software. Guests should base 365 * their gettimeofday() syscall on this wallclock-base value. 366 */ 367 uint32_t wc_version; /* Version counter: see vcpu_time_info_t. */ 368 uint32_t wc_sec; /* Secs 00:00:00 UTC, Jan 1, 1970. */ 369 uint32_t wc_nsec; /* Nsecs 00:00:00 UTC, Jan 1, 1970. */ 370 371 struct arch_shared_info arch; 372 373 }; 374 375 /* 376 * Start-of-day memory layout for the initial domain (DOM0): 377 * 1. The domain is started within contiguous virtual-memory region. 378 * 2. The contiguous region begins and ends on an aligned 4MB boundary. 379 * 3. The region start corresponds to the load address of the OS image. 380 * If the load address is not 4MB aligned then the address is rounded down. 381 * 4. This the order of bootstrap elements in the initial virtual region: 382 * a. relocated kernel image 383 * b. initial ram disk [mod_start, mod_len] 384 * c. list of allocated page frames [mfn_list, nr_pages] 385 * d. start_info_t structure [register ESI (x86)] 386 * e. bootstrap page tables [pt_base, CR3 (x86)] 387 * f. bootstrap stack [register ESP (x86)] 388 * 5. Bootstrap elements are packed together, but each is 4kB-aligned. 389 * 6. The initial ram disk may be omitted. 390 * 7. The list of page frames forms a contiguous 'pseudo-physical' memory 391 * layout for the domain. In particular, the bootstrap virtual-memory 392 * region is a 1:1 mapping to the first section of the pseudo-physical map. 393 * 8. All bootstrap elements are mapped read-writable for the guest OS. The 394 * only exception is the bootstrap page table, which is mapped read-only. 395 * 9. There is guaranteed to be at least 512kB padding after the final 396 * bootstrap element. If necessary, the bootstrap virtual region is 397 * extended by an extra 4MB to ensure this. 398 */ 399 400 #define MAX_GUEST_CMDLINE 1024 401 struct start_info { 402 /* THE FOLLOWING ARE FILLED IN BOTH ON INITIAL BOOT AND ON RESUME. */ 403 char magic[32]; /* "xen-<version>-<platform>". */ 404 unsigned long nr_pages; /* Total pages allocated to this domain. */ 405 unsigned long shared_info; /* MACHINE address of shared info struct. */ 406 uint32_t flags; /* SIF_xxx flags. */ 407 unsigned long store_mfn; /* MACHINE page number of shared page. */ 408 uint32_t store_evtchn; /* Event channel for store communication. */ 409 union { 410 struct { 411 unsigned long mfn; /* MACHINE page number of console page. */ 412 uint32_t evtchn; /* Event channel for console page. */ 413 } domU; 414 struct { 415 uint32_t info_off; /* Offset of console_info struct. */ 416 uint32_t info_size; /* Size of console_info struct from start.*/ 417 } dom0; 418 } console; 419 /* THE FOLLOWING ARE ONLY FILLED IN ON INITIAL BOOT (NOT RESUME). */ 420 unsigned long pt_base; /* VIRTUAL address of page directory. */ 421 unsigned long nr_pt_frames; /* Number of bootstrap p.t. frames. */ 422 unsigned long mfn_list; /* VIRTUAL address of page-frame list. */ 423 unsigned long mod_start; /* VIRTUAL address of pre-loaded module. */ 424 unsigned long mod_len; /* Size (bytes) of pre-loaded module. */ 425 int8_t cmd_line[MAX_GUEST_CMDLINE]; 426 }; 427 428 /* These flags are passed in the 'flags' field of start_info_t. */ 429 #define SIF_PRIVILEGED (1<<0) /* Is the domain privileged? */ 430 #define SIF_INITDOMAIN (1<<1) /* Is this the initial control domain? */ 431 432 typedef uint64_t cpumap_t; 433 434 typedef uint8_t xen_domain_handle_t[16]; 435 436 /* Turn a plain number into a C unsigned long constant. */ 437 #define __mk_unsigned_long(x) x ## UL 438 #define mk_unsigned_long(x) __mk_unsigned_long(x) 439 440 #else /* __ASSEMBLY__ */ 441 442 /* In assembly code we cannot use C numeric constant suffixes. */ 443 #define mk_unsigned_long(x) x 444 445 #endif /* !__ASSEMBLY__ */ 446 447 #endif /* __XEN_PUBLIC_XEN_H__ */ 448