/******************************************************************************

 * grant_table.h

 *

 * Interface for granting foreign access to page frames, and receiving

 * page-ownership transfers.

 *

 * 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_GRANT_TABLE_H__

#define __XEN_PUBLIC_GRANT_TABLE_H__

#include "xen.h"

/*

 * `incontents 150 gnttab Grant Tables

 *

 * Xen's grant tables provide a generic mechanism to memory sharing

 * between domains. This shared memory interface underpins the split

 * device drivers for block and network IO.

 *

 * Each domain has its own grant table. This is a data structure that

 * is shared with Xen; it allows the domain to tell Xen what kind of

 * permissions other domains have on its pages. Entries in the grant

 * table are identified by grant references. A grant reference is an

 * integer, which indexes into the grant table. It acts as a

 * capability which the grantee can use to perform operations on the

 * granter's memory.

 *

 * This capability-based system allows shared-memory communications

 * between unprivileged domains. A grant reference also encapsulates

 * the details of a shared page, removing the need for a domain to

 * know the real machine address of a page it is sharing. This makes

 * it possible to share memory correctly with domains running in

 * fully virtualised memory.

 */

/***********************************

 * GRANT TABLE REPRESENTATION

 */

/* Some rough guidelines on accessing and updating grant-table entries

 * in a concurrency-safe manner. For more information, Linux contains a

 * reference implementation for guest OSes (drivers/xen/grant_table.c, see

 * http://git.kernel.org/?p=linux/kernel/git/torvalds/linux.git;a=blob;f=drivers/xen/grant-table.c;hb=HEAD

 *

 * NB. WMB is a no-op on current-generation x86 processors. However, a

 *     compiler barrier will still be required.

 *

 * Introducing a valid entry into the grant table:

 *  1. Write ent->domid.

 *  2. Write ent->frame:

 *      GTF_permit_access:   Frame to which access is permitted.

 *      GTF_accept_transfer: Pseudo-phys frame slot being filled by new

 *                           frame, or zero if none.

 *  3. Write memory barrier (WMB).

 *  4. Write ent->flags, inc. valid type.

 *

 * Invalidating an unused GTF_permit_access entry:

 *  1. flags = ent->flags.

 *  2. Observe that !(flags & (GTF_reading|GTF_writing)).

 *  3. Check result of SMP-safe CMPXCHG(&ent->flags, flags, 0).

 *  NB. No need for WMB as reuse of entry is control-dependent on success of

 *      step 3, and all architectures guarantee ordering of ctrl-dep writes.

 *

 * Invalidating an in-use GTF_permit_access entry:

 *  This cannot be done directly. Request assistance from the domain controller

 *  which can set a timeout on the use of a grant entry and take necessary

 *  action. (NB. This is not yet implemented!).

 *

 * Invalidating an unused GTF_accept_transfer entry:

 *  1. flags = ent->flags.

 *  2. Observe that !(flags & GTF_transfer_committed). [*]

 *  3. Check result of SMP-safe CMPXCHG(&ent->flags, flags, 0).

 *  NB. No need for WMB as reuse of entry is control-dependent on success of

 *      step 3, and all architectures guarantee ordering of ctrl-dep writes.

 *  [*] If GTF_transfer_committed is set then the grant entry is 'committed'.

 *      The guest must /not/ modify the grant entry until the address of the

 *      transferred frame is written. It is safe for the guest to spin waiting

 *      for this to occur (detect by observing GTF_transfer_completed in

 *      ent->flags).

 *

 * Invalidating a committed GTF_accept_transfer entry:

 *  1. Wait for (ent->flags & GTF_transfer_completed).

 *

 * Changing a GTF_permit_access from writable to read-only:

 *  Use SMP-safe CMPXCHG to set GTF_readonly, while checking !GTF_writing.

 *

 * Changing a GTF_permit_access from read-only to writable:

 *  Use SMP-safe bit-setting instruction.

 */

/*

 * Reference to a grant entry in a specified domain's grant table.

 */

typedef uint32_t grant_ref_t;

/*

 * A grant table comprises a packed array of grant entries in one or more

 * page frames shared between Xen and a guest.

 * [XEN]: This field is written by Xen and read by the sharing guest.

 * [GST]: This field is written by the guest and read by Xen.

 */

/*

 * Version 1 of the grant table entry structure is maintained purely

 * for backwards compatibility.  New guests should use version 2.

 */

#if __XEN_INTERFACE_VERSION__ < 0x0003020a

#define grant_entry_v1 grant_entry

#define grant_entry_v1_t grant_entry_t

#endif

struct grant_entry_v1 {

    /* GTF_xxx: various type and flag information.  [XEN,GST] */

    uint16_t flags;

    /* The domain being granted foreign privileges. [GST] */

    domid_t  domid;

    /*

     * GTF_permit_access: GFN that @domid is allowed to map and access. [GST]

     * GTF_accept_transfer: GFN that @domid is allowed to transfer into. [GST]

     * GTF_transfer_completed: MFN whose ownership transferred by @domid

     *                         (non-translated guests only). [XEN]

     */

    uint32_t frame;

};

typedef struct grant_entry_v1 grant_entry_v1_t;

/* The first few grant table entries will be preserved across grant table

 * version changes and may be pre-populated at domain creation by tools.

 */

#define GNTTAB_NR_RESERVED_ENTRIES     8

#define GNTTAB_RESERVED_CONSOLE        0

#define GNTTAB_RESERVED_XENSTORE       1

/*

 * Type of grant entry.

 *  GTF_invalid: This grant entry grants no privileges.

 *  GTF_permit_access: Allow @domid to map/access @frame.

 *  GTF_accept_transfer: Allow @domid to transfer ownership of one page frame

 *                       to this guest. Xen writes the page number to @frame.

 *  GTF_transitive: Allow @domid to transitively access a subrange of

 *                  @trans_grant in @trans_domid.  No mappings are allowed.

 */

#define GTF_invalid         (0U<<0)

#define GTF_permit_access   (1U<<0)

#define GTF_accept_transfer (2U<<0)

#define GTF_transitive      (3U<<0)

#define GTF_type_mask       (3U<<0)

/*

 * Subflags for GTF_permit_access.

 *  GTF_readonly: Restrict @domid to read-only mappings and accesses. [GST]

 *  GTF_reading: Grant entry is currently mapped for reading by @domid. [XEN]

 *  GTF_writing: Grant entry is currently mapped for writing by @domid. [XEN]

 *  GTF_PAT, GTF_PWT, GTF_PCD: (x86) cache attribute flags for the grant [GST]

 *  GTF_sub_page: Grant access to only a subrange of the page.  @domid

 *                will only be allowed to copy from the grant, and not

 *                map it. [GST]

 */

#define _GTF_readonly       (2)

#define GTF_readonly        (1U<<_GTF_readonly)

#define _GTF_reading        (3)

#define GTF_reading         (1U<<_GTF_reading)

#define _GTF_writing        (4)

#define GTF_writing         (1U<<_GTF_writing)

#define _GTF_PWT            (5)

#define GTF_PWT             (1U<<_GTF_PWT)

#define _GTF_PCD            (6)

#define GTF_PCD             (1U<<_GTF_PCD)

#define _GTF_PAT            (7)

#define GTF_PAT             (1U<<_GTF_PAT)

#define _GTF_sub_page       (8)

#define GTF_sub_page        (1U<<_GTF_sub_page)

/*

 * Subflags for GTF_accept_transfer:

 *  GTF_transfer_committed: Xen sets this flag to indicate that it is committed

 *      to transferring ownership of a page frame. When a guest sees this flag

 *      it must /not/ modify the grant entry until GTF_transfer_completed is

 *      set by Xen.

 *  GTF_transfer_completed: It is safe for the guest to spin-wait on this flag

 *      after reading GTF_transfer_committed. Xen will always write the frame

 *      address, followed by ORing this flag, in a timely manner.

 */

#define _GTF_transfer_committed (2)

#define GTF_transfer_committed  (1U<<_GTF_transfer_committed)

#define _GTF_transfer_completed (3)

#define GTF_transfer_completed  (1U<<_GTF_transfer_completed)

/*

 * Version 2 grant table entries.  These fulfil the same role as

 * version 1 entries, but can represent more complicated operations.

 * Any given domain will have either a version 1 or a version 2 table,

 * and every entry in the table will be the same version.

 *

 * The interface by which domains use grant references does not depend

 * on the grant table version in use by the other domain.

 */

#if __XEN_INTERFACE_VERSION__ >= 0x0003020a

/*

 * Version 1 and version 2 grant entries share a common prefix.  The

 * fields of the prefix are documented as part of struct

 * grant_entry_v1.

 */

struct grant_entry_header {

    uint16_t flags;

    domid_t  domid;

};

typedef struct grant_entry_header grant_entry_header_t;

/*

 * Version 2 of the grant entry structure.

 */

union grant_entry_v2 {

    grant_entry_header_t hdr;

    /*

     * This member is used for V1-style full page grants, where either:

     *

     * -- hdr.type is GTF_accept_transfer, or

     * -- hdr.type is GTF_permit_access and GTF_sub_page is not set.

     *

     * In that case, the frame field has the same semantics as the

     * field of the same name in the V1 entry structure.

     */

    struct {

        grant_entry_header_t hdr;

        uint32_t pad0;

        uint64_t frame;

    } full_page;

    /*

     * If the grant type is GTF_grant_access and GTF_sub_page is set,

     * @domid is allowed to access bytes [@page_off,@page_off+@length)

     * in frame @frame.

     */

    struct {

        grant_entry_header_t hdr;

        uint16_t page_off;

        uint16_t length;

        uint64_t frame;

    } sub_page;

    /*

     * If the grant is GTF_transitive, @domid is allowed to use the

     * grant @gref in domain @trans_domid, as if it was the local

     * domain.  Obviously, the transitive access must be compatible

     * with the original grant.

     *

     * The current version of Xen does not allow transitive grants

     * to be mapped.

     */

    struct {

        grant_entry_header_t hdr;

        domid_t trans_domid;

        uint16_t pad0;

        grant_ref_t gref;

    } transitive;

    uint32_t __spacer[4]; /* Pad to a power of two */

};

typedef union grant_entry_v2 grant_entry_v2_t;

typedef uint16_t grant_status_t;

#endif /* __XEN_INTERFACE_VERSION__ */

/***********************************

 * GRANT TABLE QUERIES AND USES

 */

/* ` enum neg_errnoval

 * ` HYPERVISOR_grant_table_op(enum grant_table_op cmd,

 * `                           void *args,

 * `                           unsigned int count)

 * `

 *

 * @args points to an array of a per-command data structure. The array

 * has @count members

 */

/* ` enum grant_table_op { // GNTTABOP_* => struct gnttab_* */

#define GNTTABOP_map_grant_ref        0

#define GNTTABOP_unmap_grant_ref      1

#define GNTTABOP_setup_table          2

#define GNTTABOP_dump_table           3

#define GNTTABOP_transfer             4

#define GNTTABOP_copy                 5

#define GNTTABOP_query_size           6

#define GNTTABOP_unmap_and_replace    7

#if __XEN_INTERFACE_VERSION__ >= 0x0003020a

#define GNTTABOP_set_version          8

#define GNTTABOP_get_status_frames    9

#define GNTTABOP_get_version          10

#define GNTTABOP_swap_grant_ref       11

#define GNTTABOP_cache_flush        12

#endif /* __XEN_INTERFACE_VERSION__ */

/* ` } */

/*

 * Handle to track a mapping created via a grant reference.

 */

typedef uint32_t grant_handle_t;

/*

 * GNTTABOP_map_grant_ref: Map the grant entry (<dom>,<ref>) for access

 * by devices and/or host CPUs. If successful, <handle> is a tracking number

 * that must be presented later to destroy the mapping(s). On error, <status>

 * is a negative status code.

 * NOTES:

 *  1. If GNTMAP_device_map is specified then <dev_bus_addr> is the address

 *     via which I/O devices may access the granted frame.

 *  2. If GNTMAP_host_map is specified then a mapping will be added at

 *     either a host virtual address in the current address space, or at

 *     a PTE at the specified machine address.  The type of mapping to

 *     perform is selected through the GNTMAP_contains_pte flag, and the

 *     address is specified in <host_addr>.

 *  3. Mappings should only be destroyed via GNTTABOP_unmap_grant_ref. If a

 *     host mapping is destroyed by other means then it is *NOT* guaranteed

 *     to be accounted to the correct grant reference!

 */

struct gnttab_map_grant_ref {

    /* IN parameters. */

    uint64_t host_addr;

    uint32_t flags;               /* GNTMAP_* */

    grant_ref_t ref;

    domid_t  dom;

    /* OUT parameters. */

    int16_t  status;              /* => enum grant_status */

    grant_handle_t handle;

    uint64_t dev_bus_addr;

};

typedef struct gnttab_map_grant_ref gnttab_map_grant_ref_t;

DEFINE_XEN_GUEST_HANDLE(gnttab_map_grant_ref_t);

/*

 * GNTTABOP_unmap_grant_ref: Destroy one or more grant-reference mappings

 * tracked by <handle>. If <host_addr> or <dev_bus_addr> is zero, that

 * field is ignored. If non-zero, they must refer to a device/host mapping

 * that is tracked by <handle>

 * NOTES:

 *  1. The call may fail in an undefined manner if either mapping is not

 *     tracked by <handle>.

 *  3. After executing a batch of unmaps, it is guaranteed that no stale

 *     mappings will remain in the device or host TLBs.

 */

struct gnttab_unmap_grant_ref {

    /* IN parameters. */

    uint64_t host_addr;

    uint64_t dev_bus_addr;

    grant_handle_t handle;

    /* OUT parameters. */

    int16_t  status;              /* => enum grant_status */

};

typedef struct gnttab_unmap_grant_ref gnttab_unmap_grant_ref_t;

DEFINE_XEN_GUEST_HANDLE(gnttab_unmap_grant_ref_t);

/*

 * GNTTABOP_setup_table: Set up a grant table for <dom> comprising at least

 * <nr_frames> pages. The frame addresses are written to the <frame_list>.

 * Only <nr_frames> addresses are written, even if the table is larger.

 * NOTES:

 *  1. <dom> may be specified as DOMID_SELF.

 *  2. Only a sufficiently-privileged domain may specify <dom> != DOMID_SELF.

 *  3. Xen may not support more than a single grant-table page per domain.

 */

struct gnttab_setup_table {

    /* IN parameters. */

    domid_t  dom;

    uint32_t nr_frames;

    /* OUT parameters. */

    int16_t  status;              /* => enum grant_status */

#if __XEN_INTERFACE_VERSION__ < 0x00040300

    XEN_GUEST_HANDLE(ulong) frame_list;

#else

    XEN_GUEST_HANDLE(xen_pfn_t) frame_list;

#endif

};

typedef struct gnttab_setup_table gnttab_setup_table_t;

DEFINE_XEN_GUEST_HANDLE(gnttab_setup_table_t);

/*

 * GNTTABOP_dump_table: Dump the contents of the grant table to the

 * xen console. Debugging use only.

 */

struct gnttab_dump_table {

    /* IN parameters. */

    domid_t dom;

    /* OUT parameters. */

    int16_t status;               /* => enum grant_status */

};

typedef struct gnttab_dump_table gnttab_dump_table_t;

DEFINE_XEN_GUEST_HANDLE(gnttab_dump_table_t);

/*

 * GNTTABOP_transfer: Transfer <frame> to a foreign domain. The foreign domain

 * has previously registered its interest in the transfer via <domid, ref>.

 *

 * Note that, even if the transfer fails, the specified page no longer belongs

 * to the calling domain *unless* the error is GNTST_bad_page.

 *

 * Note further that only PV guests can use this operation.

 */

struct gnttab_transfer {

    /* IN parameters. */

    xen_pfn_t     mfn;

    domid_t       domid;

    grant_ref_t   ref;

    /* OUT parameters. */

    int16_t       status;

};

typedef struct gnttab_transfer gnttab_transfer_t;

DEFINE_XEN_GUEST_HANDLE(gnttab_transfer_t);

/*

 * GNTTABOP_copy: Hypervisor based copy

 * source and destinations can be eithers MFNs or, for foreign domains,

 * grant references. the foreign domain has to grant read/write access

 * in its grant table.

 *

 * The flags specify what type source and destinations are (either MFN

 * or grant reference).

 *

 * Note that this can also be used to copy data between two domains

 * via a third party if the source and destination domains had previously

 * grant appropriate access to their pages to the third party.

 *

 * source_offset specifies an offset in the source frame, dest_offset

 * the offset in the target frame and  len specifies the number of

 * bytes to be copied.

 */

#define _GNTCOPY_source_gref      (0)

#define GNTCOPY_source_gref       (1<<_GNTCOPY_source_gref)

#define _GNTCOPY_dest_gref        (1)

#define GNTCOPY_dest_gref         (1<<_GNTCOPY_dest_gref)

struct gnttab_copy {

    /* IN parameters. */

    struct gnttab_copy_ptr {

        union {

            grant_ref_t ref;

            xen_pfn_t   gmfn;

        } u;

        domid_t  domid;

        uint16_t offset;

    } source, dest;

    uint16_t      len;

    uint16_t      flags;          /* GNTCOPY_* */

    /* OUT parameters. */

    int16_t       status;

};

typedef struct gnttab_copy  gnttab_copy_t;

DEFINE_XEN_GUEST_HANDLE(gnttab_copy_t);

/*

 * GNTTABOP_query_size: Query the current and maximum sizes of the shared

 * grant table.

 * NOTES:

 *  1. <dom> may be specified as DOMID_SELF.

 *  2. Only a sufficiently-privileged domain may specify <dom> != DOMID_SELF.

 */

struct gnttab_query_size {

    /* IN parameters. */

    domid_t  dom;

    /* OUT parameters. */

    uint32_t nr_frames;

    uint32_t max_nr_frames;

    int16_t  status;              /* => enum grant_status */

};

typedef struct gnttab_query_size gnttab_query_size_t;

DEFINE_XEN_GUEST_HANDLE(gnttab_query_size_t);

/*

 * GNTTABOP_unmap_and_replace: Destroy one or more grant-reference mappings

 * tracked by <handle> but atomically replace the page table entry with one

 * pointing to the machine address under <new_addr>.  <new_addr> will be

 * redirected to the null entry.

 * NOTES:

 *  1. The call may fail in an undefined manner if either mapping is not

 *     tracked by <handle>.

 *  2. After executing a batch of unmaps, it is guaranteed that no stale

 *     mappings will remain in the device or host TLBs.

 */

struct gnttab_unmap_and_replace {

    /* IN parameters. */

    uint64_t host_addr;

    uint64_t new_addr;

    grant_handle_t handle;

    /* OUT parameters. */

    int16_t  status;              /* => enum grant_status */

};

typedef struct gnttab_unmap_and_replace gnttab_unmap_and_replace_t;

DEFINE_XEN_GUEST_HANDLE(gnttab_unmap_and_replace_t);

#if __XEN_INTERFACE_VERSION__ >= 0x0003020a

/*

 * GNTTABOP_set_version: Request a particular version of the grant

 * table shared table structure.  This operation can only be performed

 * once in any given domain.  It must be performed before any grants

 * are activated; otherwise, the domain will be stuck with version 1.

 * The only defined versions are 1 and 2.

 */

struct gnttab_set_version {

    /* IN/OUT parameters */

    uint32_t version;

};

typedef struct gnttab_set_version gnttab_set_version_t;

DEFINE_XEN_GUEST_HANDLE(gnttab_set_version_t);

/*

 * GNTTABOP_get_status_frames: Get the list of frames used to store grant

 * status for <dom>. In grant format version 2, the status is separated

 * from the other shared grant fields to allow more efficient synchronization

 * using barriers instead of atomic cmpexch operations.

 * <nr_frames> specify the size of vector <frame_list>.

 * The frame addresses are returned in the <frame_list>.

 * Only <nr_frames> addresses are returned, even if the table is larger.

 * NOTES:

 *  1. <dom> may be specified as DOMID_SELF.

 *  2. Only a sufficiently-privileged domain may specify <dom> != DOMID_SELF.

 */

struct gnttab_get_status_frames {

    /* IN parameters. */

    uint32_t nr_frames;

    domid_t  dom;

    /* OUT parameters. */

    int16_t  status;              /* => enum grant_status */

    XEN_GUEST_HANDLE(uint64_t) frame_list;

};

typedef struct gnttab_get_status_frames gnttab_get_status_frames_t;

DEFINE_XEN_GUEST_HANDLE(gnttab_get_status_frames_t);

/*

 * GNTTABOP_get_version: Get the grant table version which is in

 * effect for domain <dom>.

 */

struct gnttab_get_version {

    /* IN parameters */

    domid_t dom;

    uint16_t pad;

    /* OUT parameters */

    uint32_t version;

};

typedef struct gnttab_get_version gnttab_get_version_t;

DEFINE_XEN_GUEST_HANDLE(gnttab_get_version_t);

/*

 * GNTTABOP_swap_grant_ref: Swap the contents of two grant entries.

 */

struct gnttab_swap_grant_ref {

    /* IN parameters */

    grant_ref_t ref_a;

    grant_ref_t ref_b;

    /* OUT parameters */

    int16_t status;             /* => enum grant_status */

};

typedef struct gnttab_swap_grant_ref gnttab_swap_grant_ref_t;

DEFINE_XEN_GUEST_HANDLE(gnttab_swap_grant_ref_t);

/*

 * Issue one or more cache maintenance operations on a portion of a

 * page granted to the calling domain by a foreign domain.

 */

struct gnttab_cache_flush {

    union {

        uint64_t dev_bus_addr;

        grant_ref_t ref;

    } a;

    uint16_t offset; /* offset from start of grant */

    uint16_t length; /* size within the grant */

#define GNTTAB_CACHE_CLEAN          (1u<<0)

#define GNTTAB_CACHE_INVAL          (1u<<1)

#define GNTTAB_CACHE_SOURCE_GREF    (1u<<31)

    uint32_t op;

};

typedef struct gnttab_cache_flush gnttab_cache_flush_t;

DEFINE_XEN_GUEST_HANDLE(gnttab_cache_flush_t);

#endif /* __XEN_INTERFACE_VERSION__ */

/*

 * Bitfield values for gnttab_map_grant_ref.flags.

 */

 /* Map the grant entry for access by I/O devices. */

#define _GNTMAP_device_map      (0)

#define GNTMAP_device_map       (1<<_GNTMAP_device_map)

 /* Map the grant entry for access by host CPUs. */

#define _GNTMAP_host_map        (1)

#define GNTMAP_host_map         (1<<_GNTMAP_host_map)

 /* Accesses to the granted frame will be restricted to read-only access. */

#define _GNTMAP_readonly        (2)

#define GNTMAP_readonly         (1<<_GNTMAP_readonly)

 /*

  * GNTMAP_host_map subflag:

  *  0 => The host mapping is usable only by the guest OS.

  *  1 => The host mapping is usable by guest OS + current application.

  */

#define _GNTMAP_application_map (3)

#define GNTMAP_application_map  (1<<_GNTMAP_application_map)

 /*

  * GNTMAP_contains_pte subflag:

  *  0 => This map request contains a host virtual address.

  *  1 => This map request contains the machine addess of the PTE to update.

  */

#define _GNTMAP_contains_pte    (4)

#define GNTMAP_contains_pte     (1<<_GNTMAP_contains_pte)

#define _GNTMAP_can_fail        (5)

#define GNTMAP_can_fail         (1<<_GNTMAP_can_fail)

/*

 * Bits to be placed in guest kernel available PTE bits (architecture

 * dependent; only supported when XENFEAT_gnttab_map_avail_bits is set).

 */

#define _GNTMAP_guest_avail0    (16)

#define GNTMAP_guest_avail_mask ((uint32_t)~0 << _GNTMAP_guest_avail0)

/*

 * Values for error status returns. All errors are -ve.

 */

/* ` enum grant_status { */

#define GNTST_okay             (0)  /* Normal return.                        */

#define GNTST_general_error    (-1) /* General undefined error.              */

#define GNTST_bad_domain       (-2) /* Unrecognsed domain id.                */

#define GNTST_bad_gntref       (-3) /* Unrecognised or inappropriate gntref. */

#define GNTST_bad_handle       (-4) /* Unrecognised or inappropriate handle. */

#define GNTST_bad_virt_addr    (-5) /* Inappropriate virtual address to map. */

#define GNTST_bad_dev_addr     (-6) /* Inappropriate device address to unmap.*/

#define GNTST_no_device_space  (-7) /* Out of space in I/O MMU.              */

#define GNTST_permission_denied (-8) /* Not enough privilege for operation.  */

#define GNTST_bad_page         (-9) /* Specified page was invalid for op.    */

#define GNTST_bad_copy_arg    (-10) /* copy arguments cross page boundary.   */

#define GNTST_address_too_big (-11) /* transfer page address too large.      */

#define GNTST_eagain          (-12) /* Operation not done; try again.        */

/* ` } */

#define GNTTABOP_error_msgs {                   \

    "okay",                                     \

    "undefined error",                          \

    "unrecognised domain id",                   \

    "invalid grant reference",                  \

    "invalid mapping handle",                   \

    "invalid virtual address",                  \

    "invalid device address",                   \

    "no spare translation slot in the I/O MMU", \

    "permission denied",                        \

    "bad page",                                 \

    "copy arguments cross page boundary",       \

    "page address size too large",              \

    "operation not done; try again"             \

}

#endif /* __XEN_PUBLIC_GRANT_TABLE_H__ */

/*

 * Local variables:

 * mode: C

 * c-file-style: "BSD"

 * c-basic-offset: 4

 * tab-width: 4

 * indent-tabs-mode: nil

 * End:

 */