grant_table.h revision 251767
1181624Skmacy/******************************************************************************
2181624Skmacy * grant_table.h
3251767Sgibbs *
4181624Skmacy * Interface for granting foreign access to page frames, and receiving
5181624Skmacy * page-ownership transfers.
6251767Sgibbs *
7181624Skmacy * Permission is hereby granted, free of charge, to any person obtaining a copy
8181624Skmacy * of this software and associated documentation files (the "Software"), to
9181624Skmacy * deal in the Software without restriction, including without limitation the
10181624Skmacy * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
11181624Skmacy * sell copies of the Software, and to permit persons to whom the Software is
12181624Skmacy * furnished to do so, subject to the following conditions:
13181624Skmacy *
14181624Skmacy * The above copyright notice and this permission notice shall be included in
15181624Skmacy * all copies or substantial portions of the Software.
16181624Skmacy *
17181624Skmacy * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18181624Skmacy * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19181624Skmacy * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
20181624Skmacy * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
21181624Skmacy * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
22181624Skmacy * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
23181624Skmacy * DEALINGS IN THE SOFTWARE.
24181624Skmacy *
25181624Skmacy * Copyright (c) 2004, K A Fraser
26181624Skmacy */
27181624Skmacy
28181624Skmacy#ifndef __XEN_PUBLIC_GRANT_TABLE_H__
29181624Skmacy#define __XEN_PUBLIC_GRANT_TABLE_H__
30181624Skmacy
31251767Sgibbs#include "xen.h"
32181624Skmacy
33251767Sgibbs/*
34251767Sgibbs * `incontents 150 gnttab Grant Tables
35251767Sgibbs *
36251767Sgibbs * Xen's grant tables provide a generic mechanism to memory sharing
37251767Sgibbs * between domains. This shared memory interface underpins the split
38251767Sgibbs * device drivers for block and network IO.
39251767Sgibbs *
40251767Sgibbs * Each domain has its own grant table. This is a data structure that
41251767Sgibbs * is shared with Xen; it allows the domain to tell Xen what kind of
42251767Sgibbs * permissions other domains have on its pages. Entries in the grant
43251767Sgibbs * table are identified by grant references. A grant reference is an
44251767Sgibbs * integer, which indexes into the grant table. It acts as a
45251767Sgibbs * capability which the grantee can use to perform operations on the
46251767Sgibbs * granter���s memory.
47251767Sgibbs *
48251767Sgibbs * This capability-based system allows shared-memory communications
49251767Sgibbs * between unprivileged domains. A grant reference also encapsulates
50251767Sgibbs * the details of a shared page, removing the need for a domain to
51251767Sgibbs * know the real machine address of a page it is sharing. This makes
52251767Sgibbs * it possible to share memory correctly with domains running in
53251767Sgibbs * fully virtualised memory.
54251767Sgibbs */
55251767Sgibbs
56181624Skmacy/***********************************
57181624Skmacy * GRANT TABLE REPRESENTATION
58181624Skmacy */
59181624Skmacy
60181624Skmacy/* Some rough guidelines on accessing and updating grant-table entries
61181624Skmacy * in a concurrency-safe manner. For more information, Linux contains a
62251767Sgibbs * reference implementation for guest OSes (drivers/xen/grant_table.c, see
63251767Sgibbs * http://git.kernel.org/?p=linux/kernel/git/torvalds/linux.git;a=blob;f=drivers/xen/grant-table.c;hb=HEAD
64251767Sgibbs *
65181624Skmacy * NB. WMB is a no-op on current-generation x86 processors. However, a
66181624Skmacy *     compiler barrier will still be required.
67251767Sgibbs *
68181624Skmacy * Introducing a valid entry into the grant table:
69181624Skmacy *  1. Write ent->domid.
70181624Skmacy *  2. Write ent->frame:
71181624Skmacy *      GTF_permit_access:   Frame to which access is permitted.
72181624Skmacy *      GTF_accept_transfer: Pseudo-phys frame slot being filled by new
73181624Skmacy *                           frame, or zero if none.
74181624Skmacy *  3. Write memory barrier (WMB).
75181624Skmacy *  4. Write ent->flags, inc. valid type.
76251767Sgibbs *
77181624Skmacy * Invalidating an unused GTF_permit_access entry:
78181624Skmacy *  1. flags = ent->flags.
79181624Skmacy *  2. Observe that !(flags & (GTF_reading|GTF_writing)).
80181624Skmacy *  3. Check result of SMP-safe CMPXCHG(&ent->flags, flags, 0).
81181624Skmacy *  NB. No need for WMB as reuse of entry is control-dependent on success of
82181624Skmacy *      step 3, and all architectures guarantee ordering of ctrl-dep writes.
83181624Skmacy *
84181624Skmacy * Invalidating an in-use GTF_permit_access entry:
85181624Skmacy *  This cannot be done directly. Request assistance from the domain controller
86181624Skmacy *  which can set a timeout on the use of a grant entry and take necessary
87181624Skmacy *  action. (NB. This is not yet implemented!).
88251767Sgibbs *
89181624Skmacy * Invalidating an unused GTF_accept_transfer entry:
90181624Skmacy *  1. flags = ent->flags.
91181624Skmacy *  2. Observe that !(flags & GTF_transfer_committed). [*]
92181624Skmacy *  3. Check result of SMP-safe CMPXCHG(&ent->flags, flags, 0).
93181624Skmacy *  NB. No need for WMB as reuse of entry is control-dependent on success of
94181624Skmacy *      step 3, and all architectures guarantee ordering of ctrl-dep writes.
95181624Skmacy *  [*] If GTF_transfer_committed is set then the grant entry is 'committed'.
96181624Skmacy *      The guest must /not/ modify the grant entry until the address of the
97181624Skmacy *      transferred frame is written. It is safe for the guest to spin waiting
98181624Skmacy *      for this to occur (detect by observing GTF_transfer_completed in
99181624Skmacy *      ent->flags).
100181624Skmacy *
101181624Skmacy * Invalidating a committed GTF_accept_transfer entry:
102181624Skmacy *  1. Wait for (ent->flags & GTF_transfer_completed).
103181624Skmacy *
104181624Skmacy * Changing a GTF_permit_access from writable to read-only:
105181624Skmacy *  Use SMP-safe CMPXCHG to set GTF_readonly, while checking !GTF_writing.
106251767Sgibbs *
107181624Skmacy * Changing a GTF_permit_access from read-only to writable:
108181624Skmacy *  Use SMP-safe bit-setting instruction.
109181624Skmacy */
110181624Skmacy
111181624Skmacy/*
112251767Sgibbs * Reference to a grant entry in a specified domain's grant table.
113251767Sgibbs */
114251767Sgibbstypedef uint32_t grant_ref_t;
115251767Sgibbs
116251767Sgibbs/*
117181624Skmacy * A grant table comprises a packed array of grant entries in one or more
118181624Skmacy * page frames shared between Xen and a guest.
119181624Skmacy * [XEN]: This field is written by Xen and read by the sharing guest.
120181624Skmacy * [GST]: This field is written by the guest and read by Xen.
121181624Skmacy */
122251767Sgibbs
123251767Sgibbs/*
124251767Sgibbs * Version 1 of the grant table entry structure is maintained purely
125251767Sgibbs * for backwards compatibility.  New guests should use version 2.
126251767Sgibbs */
127251767Sgibbs#if __XEN_INTERFACE_VERSION__ < 0x0003020a
128251767Sgibbs#define grant_entry_v1 grant_entry
129251767Sgibbs#define grant_entry_v1_t grant_entry_t
130251767Sgibbs#endif
131251767Sgibbsstruct grant_entry_v1 {
132181624Skmacy    /* GTF_xxx: various type and flag information.  [XEN,GST] */
133181624Skmacy    uint16_t flags;
134181624Skmacy    /* The domain being granted foreign privileges. [GST] */
135181624Skmacy    domid_t  domid;
136181624Skmacy    /*
137181624Skmacy     * GTF_permit_access: Frame that @domid is allowed to map and access. [GST]
138181624Skmacy     * GTF_accept_transfer: Frame whose ownership transferred by @domid. [XEN]
139181624Skmacy     */
140181624Skmacy    uint32_t frame;
141181624Skmacy};
142251767Sgibbstypedef struct grant_entry_v1 grant_entry_v1_t;
143181624Skmacy
144251767Sgibbs/* The first few grant table entries will be preserved across grant table
145251767Sgibbs * version changes and may be pre-populated at domain creation by tools.
146251767Sgibbs */
147251767Sgibbs#define GNTTAB_NR_RESERVED_ENTRIES     8
148251767Sgibbs#define GNTTAB_RESERVED_CONSOLE        0
149251767Sgibbs#define GNTTAB_RESERVED_XENSTORE       1
150251767Sgibbs
151181624Skmacy/*
152181624Skmacy * Type of grant entry.
153181624Skmacy *  GTF_invalid: This grant entry grants no privileges.
154181624Skmacy *  GTF_permit_access: Allow @domid to map/access @frame.
155181624Skmacy *  GTF_accept_transfer: Allow @domid to transfer ownership of one page frame
156181624Skmacy *                       to this guest. Xen writes the page number to @frame.
157251767Sgibbs *  GTF_transitive: Allow @domid to transitively access a subrange of
158251767Sgibbs *                  @trans_grant in @trans_domid.  No mappings are allowed.
159181624Skmacy */
160181624Skmacy#define GTF_invalid         (0U<<0)
161181624Skmacy#define GTF_permit_access   (1U<<0)
162181624Skmacy#define GTF_accept_transfer (2U<<0)
163251767Sgibbs#define GTF_transitive      (3U<<0)
164181624Skmacy#define GTF_type_mask       (3U<<0)
165181624Skmacy
166181624Skmacy/*
167181624Skmacy * Subflags for GTF_permit_access.
168181624Skmacy *  GTF_readonly: Restrict @domid to read-only mappings and accesses. [GST]
169181624Skmacy *  GTF_reading: Grant entry is currently mapped for reading by @domid. [XEN]
170181624Skmacy *  GTF_writing: Grant entry is currently mapped for writing by @domid. [XEN]
171183340Skmacy *  GTF_PAT, GTF_PWT, GTF_PCD: (x86) cache attribute flags for the grant [GST]
172251767Sgibbs *  GTF_sub_page: Grant access to only a subrange of the page.  @domid
173251767Sgibbs *                will only be allowed to copy from the grant, and not
174251767Sgibbs *                map it. [GST]
175181624Skmacy */
176181624Skmacy#define _GTF_readonly       (2)
177181624Skmacy#define GTF_readonly        (1U<<_GTF_readonly)
178181624Skmacy#define _GTF_reading        (3)
179181624Skmacy#define GTF_reading         (1U<<_GTF_reading)
180181624Skmacy#define _GTF_writing        (4)
181181624Skmacy#define GTF_writing         (1U<<_GTF_writing)
182183340Skmacy#define _GTF_PWT            (5)
183183340Skmacy#define GTF_PWT             (1U<<_GTF_PWT)
184183340Skmacy#define _GTF_PCD            (6)
185183340Skmacy#define GTF_PCD             (1U<<_GTF_PCD)
186183340Skmacy#define _GTF_PAT            (7)
187183340Skmacy#define GTF_PAT             (1U<<_GTF_PAT)
188251767Sgibbs#define _GTF_sub_page       (8)
189251767Sgibbs#define GTF_sub_page        (1U<<_GTF_sub_page)
190181624Skmacy
191181624Skmacy/*
192181624Skmacy * Subflags for GTF_accept_transfer:
193181624Skmacy *  GTF_transfer_committed: Xen sets this flag to indicate that it is committed
194181624Skmacy *      to transferring ownership of a page frame. When a guest sees this flag
195181624Skmacy *      it must /not/ modify the grant entry until GTF_transfer_completed is
196181624Skmacy *      set by Xen.
197181624Skmacy *  GTF_transfer_completed: It is safe for the guest to spin-wait on this flag
198181624Skmacy *      after reading GTF_transfer_committed. Xen will always write the frame
199181624Skmacy *      address, followed by ORing this flag, in a timely manner.
200181624Skmacy */
201181624Skmacy#define _GTF_transfer_committed (2)
202181624Skmacy#define GTF_transfer_committed  (1U<<_GTF_transfer_committed)
203181624Skmacy#define _GTF_transfer_completed (3)
204181624Skmacy#define GTF_transfer_completed  (1U<<_GTF_transfer_completed)
205181624Skmacy
206251767Sgibbs/*
207251767Sgibbs * Version 2 grant table entries.  These fulfil the same role as
208251767Sgibbs * version 1 entries, but can represent more complicated operations.
209251767Sgibbs * Any given domain will have either a version 1 or a version 2 table,
210251767Sgibbs * and every entry in the table will be the same version.
211251767Sgibbs *
212251767Sgibbs * The interface by which domains use grant references does not depend
213251767Sgibbs * on the grant table version in use by the other domain.
214251767Sgibbs */
215251767Sgibbs#if __XEN_INTERFACE_VERSION__ >= 0x0003020a
216251767Sgibbs/*
217251767Sgibbs * Version 1 and version 2 grant entries share a common prefix.  The
218251767Sgibbs * fields of the prefix are documented as part of struct
219251767Sgibbs * grant_entry_v1.
220251767Sgibbs */
221251767Sgibbsstruct grant_entry_header {
222251767Sgibbs    uint16_t flags;
223251767Sgibbs    domid_t  domid;
224251767Sgibbs};
225251767Sgibbstypedef struct grant_entry_header grant_entry_header_t;
226181624Skmacy
227251767Sgibbs/*
228251767Sgibbs * Version 2 of the grant entry structure.
229251767Sgibbs */
230251767Sgibbsunion grant_entry_v2 {
231251767Sgibbs    grant_entry_header_t hdr;
232251767Sgibbs
233251767Sgibbs    /*
234251767Sgibbs     * This member is used for V1-style full page grants, where either:
235251767Sgibbs     *
236251767Sgibbs     * -- hdr.type is GTF_accept_transfer, or
237251767Sgibbs     * -- hdr.type is GTF_permit_access and GTF_sub_page is not set.
238251767Sgibbs     *
239251767Sgibbs     * In that case, the frame field has the same semantics as the
240251767Sgibbs     * field of the same name in the V1 entry structure.
241251767Sgibbs     */
242251767Sgibbs    struct {
243251767Sgibbs        grant_entry_header_t hdr;
244251767Sgibbs        uint32_t pad0;
245251767Sgibbs        uint64_t frame;
246251767Sgibbs    } full_page;
247251767Sgibbs
248251767Sgibbs    /*
249251767Sgibbs     * If the grant type is GTF_grant_access and GTF_sub_page is set,
250251767Sgibbs     * @domid is allowed to access bytes [@page_off,@page_off+@length)
251251767Sgibbs     * in frame @frame.
252251767Sgibbs     */
253251767Sgibbs    struct {
254251767Sgibbs        grant_entry_header_t hdr;
255251767Sgibbs        uint16_t page_off;
256251767Sgibbs        uint16_t length;
257251767Sgibbs        uint64_t frame;
258251767Sgibbs    } sub_page;
259251767Sgibbs
260251767Sgibbs    /*
261251767Sgibbs     * If the grant is GTF_transitive, @domid is allowed to use the
262251767Sgibbs     * grant @gref in domain @trans_domid, as if it was the local
263251767Sgibbs     * domain.  Obviously, the transitive access must be compatible
264251767Sgibbs     * with the original grant.
265251767Sgibbs     *
266251767Sgibbs     * The current version of Xen does not allow transitive grants
267251767Sgibbs     * to be mapped.
268251767Sgibbs     */
269251767Sgibbs    struct {
270251767Sgibbs        grant_entry_header_t hdr;
271251767Sgibbs        domid_t trans_domid;
272251767Sgibbs        uint16_t pad0;
273251767Sgibbs        grant_ref_t gref;
274251767Sgibbs    } transitive;
275251767Sgibbs
276251767Sgibbs    uint32_t __spacer[4]; /* Pad to a power of two */
277251767Sgibbs};
278251767Sgibbstypedef union grant_entry_v2 grant_entry_v2_t;
279251767Sgibbs
280251767Sgibbstypedef uint16_t grant_status_t;
281251767Sgibbs
282251767Sgibbs#endif /* __XEN_INTERFACE_VERSION__ */
283251767Sgibbs
284181624Skmacy/***********************************
285181624Skmacy * GRANT TABLE QUERIES AND USES
286181624Skmacy */
287181624Skmacy
288251767Sgibbs/* ` enum neg_errnoval
289251767Sgibbs * ` HYPERVISOR_grant_table_op(enum grant_table_op cmd,
290251767Sgibbs * `                           void *args,
291251767Sgibbs * `                           unsigned int count)
292251767Sgibbs * `
293251767Sgibbs *
294251767Sgibbs * @args points to an array of a per-command data structure. The array
295251767Sgibbs * has @count members
296181624Skmacy */
297181624Skmacy
298251767Sgibbs/* ` enum grant_table_op { // GNTTABOP_* => struct gnttab_* */
299251767Sgibbs#define GNTTABOP_map_grant_ref        0
300251767Sgibbs#define GNTTABOP_unmap_grant_ref      1
301251767Sgibbs#define GNTTABOP_setup_table          2
302251767Sgibbs#define GNTTABOP_dump_table           3
303251767Sgibbs#define GNTTABOP_transfer             4
304251767Sgibbs#define GNTTABOP_copy                 5
305251767Sgibbs#define GNTTABOP_query_size           6
306251767Sgibbs#define GNTTABOP_unmap_and_replace    7
307251767Sgibbs#if __XEN_INTERFACE_VERSION__ >= 0x0003020a
308251767Sgibbs#define GNTTABOP_set_version          8
309251767Sgibbs#define GNTTABOP_get_status_frames    9
310251767Sgibbs#define GNTTABOP_get_version          10
311251767Sgibbs#define GNTTABOP_swap_grant_ref	      11
312251767Sgibbs#endif /* __XEN_INTERFACE_VERSION__ */
313251767Sgibbs/* ` } */
314214077Sgibbs
315181624Skmacy/*
316181624Skmacy * Handle to track a mapping created via a grant reference.
317181624Skmacy */
318181624Skmacytypedef uint32_t grant_handle_t;
319181624Skmacy
320181624Skmacy/*
321181624Skmacy * GNTTABOP_map_grant_ref: Map the grant entry (<dom>,<ref>) for access
322181624Skmacy * by devices and/or host CPUs. If successful, <handle> is a tracking number
323181624Skmacy * that must be presented later to destroy the mapping(s). On error, <handle>
324181624Skmacy * is a negative status code.
325181624Skmacy * NOTES:
326181624Skmacy *  1. If GNTMAP_device_map is specified then <dev_bus_addr> is the address
327181624Skmacy *     via which I/O devices may access the granted frame.
328181624Skmacy *  2. If GNTMAP_host_map is specified then a mapping will be added at
329181624Skmacy *     either a host virtual address in the current address space, or at
330181624Skmacy *     a PTE at the specified machine address.  The type of mapping to
331251767Sgibbs *     perform is selected through the GNTMAP_contains_pte flag, and the
332181624Skmacy *     address is specified in <host_addr>.
333181624Skmacy *  3. Mappings should only be destroyed via GNTTABOP_unmap_grant_ref. If a
334181624Skmacy *     host mapping is destroyed by other means then it is *NOT* guaranteed
335181624Skmacy *     to be accounted to the correct grant reference!
336181624Skmacy */
337181624Skmacystruct gnttab_map_grant_ref {
338181624Skmacy    /* IN parameters. */
339181624Skmacy    uint64_t host_addr;
340181624Skmacy    uint32_t flags;               /* GNTMAP_* */
341181624Skmacy    grant_ref_t ref;
342181624Skmacy    domid_t  dom;
343181624Skmacy    /* OUT parameters. */
344251767Sgibbs    int16_t  status;              /* => enum grant_status */
345181624Skmacy    grant_handle_t handle;
346181624Skmacy    uint64_t dev_bus_addr;
347181624Skmacy};
348181624Skmacytypedef struct gnttab_map_grant_ref gnttab_map_grant_ref_t;
349181624SkmacyDEFINE_XEN_GUEST_HANDLE(gnttab_map_grant_ref_t);
350181624Skmacy
351181624Skmacy/*
352181624Skmacy * GNTTABOP_unmap_grant_ref: Destroy one or more grant-reference mappings
353181624Skmacy * tracked by <handle>. If <host_addr> or <dev_bus_addr> is zero, that
354181624Skmacy * field is ignored. If non-zero, they must refer to a device/host mapping
355181624Skmacy * that is tracked by <handle>
356181624Skmacy * NOTES:
357181624Skmacy *  1. The call may fail in an undefined manner if either mapping is not
358181624Skmacy *     tracked by <handle>.
359181624Skmacy *  3. After executing a batch of unmaps, it is guaranteed that no stale
360181624Skmacy *     mappings will remain in the device or host TLBs.
361181624Skmacy */
362181624Skmacystruct gnttab_unmap_grant_ref {
363181624Skmacy    /* IN parameters. */
364181624Skmacy    uint64_t host_addr;
365181624Skmacy    uint64_t dev_bus_addr;
366181624Skmacy    grant_handle_t handle;
367181624Skmacy    /* OUT parameters. */
368251767Sgibbs    int16_t  status;              /* => enum grant_status */
369181624Skmacy};
370181624Skmacytypedef struct gnttab_unmap_grant_ref gnttab_unmap_grant_ref_t;
371181624SkmacyDEFINE_XEN_GUEST_HANDLE(gnttab_unmap_grant_ref_t);
372181624Skmacy
373181624Skmacy/*
374181624Skmacy * GNTTABOP_setup_table: Set up a grant table for <dom> comprising at least
375181624Skmacy * <nr_frames> pages. The frame addresses are written to the <frame_list>.
376181624Skmacy * Only <nr_frames> addresses are written, even if the table is larger.
377181624Skmacy * NOTES:
378181624Skmacy *  1. <dom> may be specified as DOMID_SELF.
379181624Skmacy *  2. Only a sufficiently-privileged domain may specify <dom> != DOMID_SELF.
380181624Skmacy *  3. Xen may not support more than a single grant-table page per domain.
381181624Skmacy */
382181624Skmacystruct gnttab_setup_table {
383181624Skmacy    /* IN parameters. */
384181624Skmacy    domid_t  dom;
385181624Skmacy    uint32_t nr_frames;
386181624Skmacy    /* OUT parameters. */
387251767Sgibbs    int16_t  status;              /* => enum grant_status */
388183375Skmacy    XEN_GUEST_HANDLE(ulong) frame_list;
389181624Skmacy};
390181624Skmacytypedef struct gnttab_setup_table gnttab_setup_table_t;
391181624SkmacyDEFINE_XEN_GUEST_HANDLE(gnttab_setup_table_t);
392181624Skmacy
393181624Skmacy/*
394181624Skmacy * GNTTABOP_dump_table: Dump the contents of the grant table to the
395181624Skmacy * xen console. Debugging use only.
396181624Skmacy */
397181624Skmacystruct gnttab_dump_table {
398181624Skmacy    /* IN parameters. */
399181624Skmacy    domid_t dom;
400181624Skmacy    /* OUT parameters. */
401251767Sgibbs    int16_t status;               /* => enum grant_status */
402181624Skmacy};
403181624Skmacytypedef struct gnttab_dump_table gnttab_dump_table_t;
404181624SkmacyDEFINE_XEN_GUEST_HANDLE(gnttab_dump_table_t);
405181624Skmacy
406181624Skmacy/*
407181624Skmacy * GNTTABOP_transfer_grant_ref: Transfer <frame> to a foreign domain. The
408181624Skmacy * foreign domain has previously registered its interest in the transfer via
409181624Skmacy * <domid, ref>.
410251767Sgibbs *
411181624Skmacy * Note that, even if the transfer fails, the specified page no longer belongs
412181624Skmacy * to the calling domain *unless* the error is GNTST_bad_page.
413181624Skmacy */
414181624Skmacystruct gnttab_transfer {
415181624Skmacy    /* IN parameters. */
416181624Skmacy    xen_pfn_t     mfn;
417181624Skmacy    domid_t       domid;
418181624Skmacy    grant_ref_t   ref;
419181624Skmacy    /* OUT parameters. */
420181624Skmacy    int16_t       status;
421181624Skmacy};
422181624Skmacytypedef struct gnttab_transfer gnttab_transfer_t;
423181624SkmacyDEFINE_XEN_GUEST_HANDLE(gnttab_transfer_t);
424181624Skmacy
425181624Skmacy
426181624Skmacy/*
427181624Skmacy * GNTTABOP_copy: Hypervisor based copy
428181624Skmacy * source and destinations can be eithers MFNs or, for foreign domains,
429181624Skmacy * grant references. the foreign domain has to grant read/write access
430181624Skmacy * in its grant table.
431181624Skmacy *
432181624Skmacy * The flags specify what type source and destinations are (either MFN
433181624Skmacy * or grant reference).
434181624Skmacy *
435181624Skmacy * Note that this can also be used to copy data between two domains
436181624Skmacy * via a third party if the source and destination domains had previously
437181624Skmacy * grant appropriate access to their pages to the third party.
438181624Skmacy *
439181624Skmacy * source_offset specifies an offset in the source frame, dest_offset
440181624Skmacy * the offset in the target frame and  len specifies the number of
441181624Skmacy * bytes to be copied.
442181624Skmacy */
443181624Skmacy
444181624Skmacy#define _GNTCOPY_source_gref      (0)
445181624Skmacy#define GNTCOPY_source_gref       (1<<_GNTCOPY_source_gref)
446181624Skmacy#define _GNTCOPY_dest_gref        (1)
447181624Skmacy#define GNTCOPY_dest_gref         (1<<_GNTCOPY_dest_gref)
448251767Sgibbs#define _GNTCOPY_can_fail         (2)
449251767Sgibbs#define GNTCOPY_can_fail          (1<<_GNTCOPY_can_fail)
450181624Skmacy
451251767Sgibbsstruct gnttab_copy {
452181624Skmacy    /* IN parameters. */
453181624Skmacy    struct {
454181624Skmacy        union {
455181624Skmacy            grant_ref_t ref;
456181624Skmacy            xen_pfn_t   gmfn;
457181624Skmacy        } u;
458181624Skmacy        domid_t  domid;
459181624Skmacy        uint16_t offset;
460181624Skmacy    } source, dest;
461181624Skmacy    uint16_t      len;
462181624Skmacy    uint16_t      flags;          /* GNTCOPY_* */
463181624Skmacy    /* OUT parameters. */
464181624Skmacy    int16_t       status;
465251767Sgibbs};
466251767Sgibbstypedef struct gnttab_copy  gnttab_copy_t;
467181624SkmacyDEFINE_XEN_GUEST_HANDLE(gnttab_copy_t);
468181624Skmacy
469181624Skmacy/*
470181624Skmacy * GNTTABOP_query_size: Query the current and maximum sizes of the shared
471181624Skmacy * grant table.
472181624Skmacy * NOTES:
473181624Skmacy *  1. <dom> may be specified as DOMID_SELF.
474181624Skmacy *  2. Only a sufficiently-privileged domain may specify <dom> != DOMID_SELF.
475181624Skmacy */
476181624Skmacystruct gnttab_query_size {
477181624Skmacy    /* IN parameters. */
478181624Skmacy    domid_t  dom;
479181624Skmacy    /* OUT parameters. */
480181624Skmacy    uint32_t nr_frames;
481181624Skmacy    uint32_t max_nr_frames;
482251767Sgibbs    int16_t  status;              /* => enum grant_status */
483181624Skmacy};
484181624Skmacytypedef struct gnttab_query_size gnttab_query_size_t;
485181624SkmacyDEFINE_XEN_GUEST_HANDLE(gnttab_query_size_t);
486181624Skmacy
487183340Skmacy/*
488183340Skmacy * GNTTABOP_unmap_and_replace: Destroy one or more grant-reference mappings
489183340Skmacy * tracked by <handle> but atomically replace the page table entry with one
490183340Skmacy * pointing to the machine address under <new_addr>.  <new_addr> will be
491183340Skmacy * redirected to the null entry.
492183340Skmacy * NOTES:
493183340Skmacy *  1. The call may fail in an undefined manner if either mapping is not
494183340Skmacy *     tracked by <handle>.
495183340Skmacy *  2. After executing a batch of unmaps, it is guaranteed that no stale
496183340Skmacy *     mappings will remain in the device or host TLBs.
497183340Skmacy */
498183340Skmacystruct gnttab_unmap_and_replace {
499183340Skmacy    /* IN parameters. */
500183340Skmacy    uint64_t host_addr;
501183340Skmacy    uint64_t new_addr;
502183340Skmacy    grant_handle_t handle;
503183340Skmacy    /* OUT parameters. */
504251767Sgibbs    int16_t  status;              /* => enum grant_status */
505183340Skmacy};
506183340Skmacytypedef struct gnttab_unmap_and_replace gnttab_unmap_and_replace_t;
507183340SkmacyDEFINE_XEN_GUEST_HANDLE(gnttab_unmap_and_replace_t);
508181624Skmacy
509251767Sgibbs#if __XEN_INTERFACE_VERSION__ >= 0x0003020a
510251767Sgibbs/*
511251767Sgibbs * GNTTABOP_set_version: Request a particular version of the grant
512251767Sgibbs * table shared table structure.  This operation can only be performed
513251767Sgibbs * once in any given domain.  It must be performed before any grants
514251767Sgibbs * are activated; otherwise, the domain will be stuck with version 1.
515251767Sgibbs * The only defined versions are 1 and 2.
516251767Sgibbs */
517251767Sgibbsstruct gnttab_set_version {
518251767Sgibbs    /* IN/OUT parameters */
519251767Sgibbs    uint32_t version;
520251767Sgibbs};
521251767Sgibbstypedef struct gnttab_set_version gnttab_set_version_t;
522251767SgibbsDEFINE_XEN_GUEST_HANDLE(gnttab_set_version_t);
523183340Skmacy
524251767Sgibbs
525181624Skmacy/*
526251767Sgibbs * GNTTABOP_get_status_frames: Get the list of frames used to store grant
527251767Sgibbs * status for <dom>. In grant format version 2, the status is separated
528251767Sgibbs * from the other shared grant fields to allow more efficient synchronization
529251767Sgibbs * using barriers instead of atomic cmpexch operations.
530251767Sgibbs * <nr_frames> specify the size of vector <frame_list>.
531251767Sgibbs * The frame addresses are returned in the <frame_list>.
532251767Sgibbs * Only <nr_frames> addresses are returned, even if the table is larger.
533251767Sgibbs * NOTES:
534251767Sgibbs *  1. <dom> may be specified as DOMID_SELF.
535251767Sgibbs *  2. Only a sufficiently-privileged domain may specify <dom> != DOMID_SELF.
536181624Skmacy */
537251767Sgibbsstruct gnttab_get_status_frames {
538251767Sgibbs    /* IN parameters. */
539251767Sgibbs    uint32_t nr_frames;
540251767Sgibbs    domid_t  dom;
541251767Sgibbs    /* OUT parameters. */
542251767Sgibbs    int16_t  status;              /* => enum grant_status */
543251767Sgibbs    XEN_GUEST_HANDLE(uint64_t) frame_list;
544251767Sgibbs};
545251767Sgibbstypedef struct gnttab_get_status_frames gnttab_get_status_frames_t;
546251767SgibbsDEFINE_XEN_GUEST_HANDLE(gnttab_get_status_frames_t);
547251767Sgibbs
548251767Sgibbs/*
549251767Sgibbs * GNTTABOP_get_version: Get the grant table version which is in
550251767Sgibbs * effect for domain <dom>.
551251767Sgibbs */
552251767Sgibbsstruct gnttab_get_version {
553251767Sgibbs    /* IN parameters */
554251767Sgibbs    domid_t dom;
555251767Sgibbs    uint16_t pad;
556251767Sgibbs    /* OUT parameters */
557251767Sgibbs    uint32_t version;
558251767Sgibbs};
559251767Sgibbstypedef struct gnttab_get_version gnttab_get_version_t;
560251767SgibbsDEFINE_XEN_GUEST_HANDLE(gnttab_get_version_t);
561251767Sgibbs
562251767Sgibbs/*
563251767Sgibbs * GNTTABOP_swap_grant_ref: Swap the contents of two grant entries.
564251767Sgibbs */
565251767Sgibbsstruct gnttab_swap_grant_ref {
566251767Sgibbs    /* IN parameters */
567251767Sgibbs    grant_ref_t ref_a;
568251767Sgibbs    grant_ref_t ref_b;
569251767Sgibbs    /* OUT parameters */
570251767Sgibbs    int16_t status;             /* => enum grant_status */
571251767Sgibbs};
572251767Sgibbstypedef struct gnttab_swap_grant_ref gnttab_swap_grant_ref_t;
573251767SgibbsDEFINE_XEN_GUEST_HANDLE(gnttab_swap_grant_ref_t);
574251767Sgibbs
575251767Sgibbs#endif /* __XEN_INTERFACE_VERSION__ */
576251767Sgibbs
577251767Sgibbs/*
578251767Sgibbs * Bitfield values for gnttab_map_grant_ref.flags.
579251767Sgibbs */
580181624Skmacy /* Map the grant entry for access by I/O devices. */
581181624Skmacy#define _GNTMAP_device_map      (0)
582181624Skmacy#define GNTMAP_device_map       (1<<_GNTMAP_device_map)
583181624Skmacy /* Map the grant entry for access by host CPUs. */
584181624Skmacy#define _GNTMAP_host_map        (1)
585181624Skmacy#define GNTMAP_host_map         (1<<_GNTMAP_host_map)
586181624Skmacy /* Accesses to the granted frame will be restricted to read-only access. */
587181624Skmacy#define _GNTMAP_readonly        (2)
588181624Skmacy#define GNTMAP_readonly         (1<<_GNTMAP_readonly)
589181624Skmacy /*
590181624Skmacy  * GNTMAP_host_map subflag:
591181624Skmacy  *  0 => The host mapping is usable only by the guest OS.
592181624Skmacy  *  1 => The host mapping is usable by guest OS + current application.
593181624Skmacy  */
594181624Skmacy#define _GNTMAP_application_map (3)
595181624Skmacy#define GNTMAP_application_map  (1<<_GNTMAP_application_map)
596181624Skmacy
597181624Skmacy /*
598181624Skmacy  * GNTMAP_contains_pte subflag:
599181624Skmacy  *  0 => This map request contains a host virtual address.
600181624Skmacy  *  1 => This map request contains the machine addess of the PTE to update.
601181624Skmacy  */
602181624Skmacy#define _GNTMAP_contains_pte    (4)
603181624Skmacy#define GNTMAP_contains_pte     (1<<_GNTMAP_contains_pte)
604181624Skmacy
605251767Sgibbs#define _GNTMAP_can_fail        (5)
606251767Sgibbs#define GNTMAP_can_fail         (1<<_GNTMAP_can_fail)
607251767Sgibbs
608181624Skmacy/*
609251767Sgibbs * Bits to be placed in guest kernel available PTE bits (architecture
610251767Sgibbs * dependent; only supported when XENFEAT_gnttab_map_avail_bits is set).
611251767Sgibbs */
612251767Sgibbs#define _GNTMAP_guest_avail0    (16)
613251767Sgibbs#define GNTMAP_guest_avail_mask ((uint32_t)~0 << _GNTMAP_guest_avail0)
614251767Sgibbs
615251767Sgibbs/*
616181624Skmacy * Values for error status returns. All errors are -ve.
617181624Skmacy */
618251767Sgibbs/* ` enum grant_status { */
619181624Skmacy#define GNTST_okay             (0)  /* Normal return.                        */
620181624Skmacy#define GNTST_general_error    (-1) /* General undefined error.              */
621181624Skmacy#define GNTST_bad_domain       (-2) /* Unrecognsed domain id.                */
622181624Skmacy#define GNTST_bad_gntref       (-3) /* Unrecognised or inappropriate gntref. */
623181624Skmacy#define GNTST_bad_handle       (-4) /* Unrecognised or inappropriate handle. */
624181624Skmacy#define GNTST_bad_virt_addr    (-5) /* Inappropriate virtual address to map. */
625181624Skmacy#define GNTST_bad_dev_addr     (-6) /* Inappropriate device address to unmap.*/
626181624Skmacy#define GNTST_no_device_space  (-7) /* Out of space in I/O MMU.              */
627181624Skmacy#define GNTST_permission_denied (-8) /* Not enough privilege for operation.  */
628181624Skmacy#define GNTST_bad_page         (-9) /* Specified page was invalid for op.    */
629181624Skmacy#define GNTST_bad_copy_arg    (-10) /* copy arguments cross page boundary.   */
630181624Skmacy#define GNTST_address_too_big (-11) /* transfer page address too large.      */
631251767Sgibbs#define GNTST_eagain          (-12) /* Operation not done; try again.        */
632251767Sgibbs/* ` } */
633181624Skmacy
634181624Skmacy#define GNTTABOP_error_msgs {                   \
635181624Skmacy    "okay",                                     \
636181624Skmacy    "undefined error",                          \
637181624Skmacy    "unrecognised domain id",                   \
638181624Skmacy    "invalid grant reference",                  \
639181624Skmacy    "invalid mapping handle",                   \
640181624Skmacy    "invalid virtual address",                  \
641181624Skmacy    "invalid device address",                   \
642181624Skmacy    "no spare translation slot in the I/O MMU", \
643181624Skmacy    "permission denied",                        \
644181624Skmacy    "bad page",                                 \
645181624Skmacy    "copy arguments cross page boundary",       \
646251767Sgibbs    "page address size too large",              \
647251767Sgibbs    "operation not done; try again"             \
648181624Skmacy}
649181624Skmacy
650181624Skmacy#endif /* __XEN_PUBLIC_GRANT_TABLE_H__ */
651181624Skmacy
652181624Skmacy/*
653181624Skmacy * Local variables:
654181624Skmacy * mode: C
655181624Skmacy * c-set-style: "BSD"
656181624Skmacy * c-basic-offset: 4
657181624Skmacy * tab-width: 4
658181624Skmacy * indent-tabs-mode: nil
659181624Skmacy * End:
660181624Skmacy */
661