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linux/include/xen/interface/xen.h
Paul Durrant 3ad0876554 xen/privcmd: add IOCTL_PRIVCMD_MMAP_RESOURCE 
My recent Xen patch series introduces a new HYPERVISOR_memory_op to
support direct priv-mapping of certain guest resources (such as ioreq
pages, used by emulators) by a tools domain, rather than having to access
such resources via the guest P2M.

This patch adds the necessary infrastructure to the privcmd driver and
Xen MMU code to support direct resource mapping.

NOTE: The adjustment in the MMU code is partially cosmetic. Xen will now
      allow a PV tools domain to map guest pages either by GFN or MFN, thus
      the term 'mfn' has been swapped for 'pfn' in the lower layers of the
      remap code.

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
2018-05-14 15:25:37 +02:00

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/******************************************************************************
* xen.h
*
* Guest OS interface to Xen.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to
* deal in the Software without restriction, including without limitation the
* rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
* sell copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
* DEALINGS IN THE SOFTWARE.
*
* 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 __ASSEMBLY__
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 __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)
/* 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;
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;
xen_ulong_t evtchn_pending_sel;
struct arch_vcpu_info arch;
struct pvclock_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.
*/
xen_ulong_t evtchn_pending[sizeof(xen_ulong_t) * 8];
xen_ulong_t evtchn_mask[sizeof(xen_ulong_t) * 8];
/*
* Wallclock time: updated only by control software. Guests should base
* their gettimeofday() syscall on this wallclock-base value.
*/
struct pvclock_wall_clock wc;
struct arch_shared_info arch;
};
/*
* Start-of-day memory layout
*
* 1. The domain is started within contiguous virtual-memory region.
* 2. The contiguous region begins and ends on an aligned 4MB boundary.
* 3. This the order of bootstrap elements in the initial virtual region:
* a. relocated kernel image
* b. initial ram disk [mod_start, mod_len]
* (may be omitted)
* c. list of allocated page frames [mfn_list, nr_pages]
* (unless relocated due to XEN_ELFNOTE_INIT_P2M)
* d. start_info_t structure [register ESI (x86)]
* in case of dom0 this page contains the console info, too
* e. unless dom0: xenstore ring page
* f. unless dom0: console ring page
* g. bootstrap page tables [pt_base, CR3 (x86)]
* h. bootstrap stack [register ESP (x86)]
* 4. Bootstrap elements are packed together, but each is 4kB-aligned.
* 5. 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.
* 6. All bootstrap elements are mapped read-writable for the guest OS. The
* only exception is the bootstrap page table, which is mapped read-only.
* 7. 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-<version>-<platform>". */
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. */
xen_pfn_t store_mfn; /* MACHINE page number of shared page. */
uint32_t store_evtchn; /* Event channel for store communication. */
union {
struct {
xen_pfn_t 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];
/* The pfn range here covers both page table and p->m table frames. */
unsigned long first_p2m_pfn;/* 1st pfn forming initial P->M table. */
unsigned long nr_p2m_frames;/* # of pfns forming initial P->M table. */
};
/* 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? */
#define SIF_MULTIBOOT_MOD (1<<2) /* Is mod_start a multiboot module? */
#define SIF_MOD_START_PFN (1<<3) /* Is mod_start a PFN? */
#define SIF_VIRT_P2M_4TOOLS (1<<4) /* Do Xen tools understand a virt. mapped */
/* P->M making the 3 level tree obsolete? */
#define SIF_PM_MASK (0xFF<<8) /* reserve 1 byte for xen-pm options */
/*
* A multiboot module is a package containing modules very similar to a
* multiboot module array. The only differences are:
* - the array of module descriptors is by convention simply at the beginning
* of the multiboot module,
* - addresses in the module descriptors are based on the beginning of the
* multiboot module,
* - the number of modules is determined by a termination descriptor that has
* mod_start == 0.
*
* This permits to both build it statically and reference it in a configuration
* file, and let the PV guest easily rebase the addresses to virtual addresses
* and at the same time count the number of modules.
*/
struct xen_multiboot_mod_list {
/* Address of first byte of the module */
uint32_t mod_start;
/* Address of last byte of the module (inclusive) */
uint32_t mod_end;
/* Address of zero-terminated command line */
uint32_t cmdline;
/* Unused, must be zero */
uint32_t pad;
};
/*
* The console structure in start_info.console.dom0
*
* This structure includes a variety of information required to
* have a working VGA/VESA console.
*/
struct dom0_vga_console_info {
uint8_t video_type;
#define XEN_VGATYPE_TEXT_MODE_3 0x03
#define XEN_VGATYPE_VESA_LFB 0x23
#define XEN_VGATYPE_EFI_LFB 0x70
union {
struct {
/* Font height, in pixels. */
uint16_t font_height;
/* Cursor location (column, row). */
uint16_t cursor_x, cursor_y;
/* Number of rows and columns (dimensions in characters). */
uint16_t rows, columns;
} text_mode_3;
struct {
/* Width and height, in pixels. */
uint16_t width, height;
/* Bytes per scan line. */
uint16_t bytes_per_line;
/* Bits per pixel. */
uint16_t bits_per_pixel;
/* LFB physical address, and size (in units of 64kB). */
uint32_t lfb_base;
uint32_t lfb_size;
/* RGB mask offsets and sizes, as defined by VBE 1.2+ */
uint8_t red_pos, red_size;
uint8_t green_pos, green_size;
uint8_t blue_pos, blue_size;
uint8_t rsvd_pos, rsvd_size;
/* VESA capabilities (offset 0xa, VESA command 0x4f00). */
uint32_t gbl_caps;
/* Mode attributes (offset 0x0, VESA command 0x4f01). */
uint16_t mode_attrs;
} vesa_lfb;
} u;
};
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)
#define TMEM_SPEC_VERSION 1
struct tmem_op {
uint32_t cmd;
int32_t pool_id;
union {
struct { /* for cmd == TMEM_NEW_POOL */
uint64_t uuid[2];
uint32_t flags;
} new;
struct {
uint64_t oid[3];
uint32_t index;
uint32_t tmem_offset;
uint32_t pfn_offset;
uint32_t len;
GUEST_HANDLE(void) gmfn; /* guest machine page frame */
} gen;
} u;
};
DEFINE_GUEST_HANDLE(u64);
#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__ */
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