1 /******************************************************************************
2  * memory.h
3  *
4  * Memory reservation and information.
5  *
6  * Copyright (c) 2005, Keir Fraser <keir@xensource.com>
7  */
8 
9 #ifndef __XEN_PUBLIC_MEMORY_H__
10 #define __XEN_PUBLIC_MEMORY_H__
11 
12 #include <linux/spinlock.h>
13 
14 /*
15  * Increase or decrease the specified domain's memory reservation. Returns a
16  * -ve errcode on failure, or the # extents successfully allocated or freed.
17  * arg == addr of struct xen_memory_reservation.
18  */
19 #define XENMEM_increase_reservation 0
20 #define XENMEM_decrease_reservation 1
21 #define XENMEM_populate_physmap     6
22 struct xen_memory_reservation {
23 
24     /*
25      * XENMEM_increase_reservation:
26      *   OUT: MFN (*not* GMFN) bases of extents that were allocated
27      * XENMEM_decrease_reservation:
28      *   IN:  GMFN bases of extents to free
29      * XENMEM_populate_physmap:
30      *   IN:  GPFN bases of extents to populate with memory
31      *   OUT: GMFN bases of extents that were allocated
32      *   (NB. This command also updates the mach_to_phys translation table)
33      */
34     GUEST_HANDLE(ulong) extent_start;
35 
36     /* Number of extents, and size/alignment of each (2^extent_order pages). */
37     unsigned long  nr_extents;
38     unsigned int   extent_order;
39 
40     /*
41      * Maximum # bits addressable by the user of the allocated region (e.g.,
42      * I/O devices often have a 32-bit limitation even in 64-bit systems). If
43      * zero then the user has no addressing restriction.
44      * This field is not used by XENMEM_decrease_reservation.
45      */
46     unsigned int   address_bits;
47 
48     /*
49      * Domain whose reservation is being changed.
50      * Unprivileged domains can specify only DOMID_SELF.
51      */
52     domid_t        domid;
53 
54 };
55 DEFINE_GUEST_HANDLE_STRUCT(xen_memory_reservation);
56 
57 /*
58  * An atomic exchange of memory pages. If return code is zero then
59  * @out.extent_list provides GMFNs of the newly-allocated memory.
60  * Returns zero on complete success, otherwise a negative error code.
61  * On complete success then always @nr_exchanged == @in.nr_extents.
62  * On partial success @nr_exchanged indicates how much work was done.
63  */
64 #define XENMEM_exchange             11
65 struct xen_memory_exchange {
66     /*
67      * [IN] Details of memory extents to be exchanged (GMFN bases).
68      * Note that @in.address_bits is ignored and unused.
69      */
70     struct xen_memory_reservation in;
71 
72     /*
73      * [IN/OUT] Details of new memory extents.
74      * We require that:
75      *  1. @in.domid == @out.domid
76      *  2. @in.nr_extents  << @in.extent_order ==
77      *     @out.nr_extents << @out.extent_order
78      *  3. @in.extent_start and @out.extent_start lists must not overlap
79      *  4. @out.extent_start lists GPFN bases to be populated
80      *  5. @out.extent_start is overwritten with allocated GMFN bases
81      */
82     struct xen_memory_reservation out;
83 
84     /*
85      * [OUT] Number of input extents that were successfully exchanged:
86      *  1. The first @nr_exchanged input extents were successfully
87      *     deallocated.
88      *  2. The corresponding first entries in the output extent list correctly
89      *     indicate the GMFNs that were successfully exchanged.
90      *  3. All other input and output extents are untouched.
91      *  4. If not all input exents are exchanged then the return code of this
92      *     command will be non-zero.
93      *  5. THIS FIELD MUST BE INITIALISED TO ZERO BY THE CALLER!
94      */
95     unsigned long nr_exchanged;
96 };
97 
98 DEFINE_GUEST_HANDLE_STRUCT(xen_memory_exchange);
99 /*
100  * Returns the maximum machine frame number of mapped RAM in this system.
101  * This command always succeeds (it never returns an error code).
102  * arg == NULL.
103  */
104 #define XENMEM_maximum_ram_page     2
105 
106 /*
107  * Returns the current or maximum memory reservation, in pages, of the
108  * specified domain (may be DOMID_SELF). Returns -ve errcode on failure.
109  * arg == addr of domid_t.
110  */
111 #define XENMEM_current_reservation  3
112 #define XENMEM_maximum_reservation  4
113 
114 /*
115  * Returns a list of MFN bases of 2MB extents comprising the machine_to_phys
116  * mapping table. Architectures which do not have a m2p table do not implement
117  * this command.
118  * arg == addr of xen_machphys_mfn_list_t.
119  */
120 #define XENMEM_machphys_mfn_list    5
121 struct xen_machphys_mfn_list {
122     /*
123      * Size of the 'extent_start' array. Fewer entries will be filled if the
124      * machphys table is smaller than max_extents * 2MB.
125      */
126     unsigned int max_extents;
127 
128     /*
129      * Pointer to buffer to fill with list of extent starts. If there are
130      * any large discontiguities in the machine address space, 2MB gaps in
131      * the machphys table will be represented by an MFN base of zero.
132      */
133     GUEST_HANDLE(ulong) extent_start;
134 
135     /*
136      * Number of extents written to the above array. This will be smaller
137      * than 'max_extents' if the machphys table is smaller than max_e * 2MB.
138      */
139     unsigned int nr_extents;
140 };
141 DEFINE_GUEST_HANDLE_STRUCT(xen_machphys_mfn_list);
142 
143 /*
144  * Returns the location in virtual address space of the machine_to_phys
145  * mapping table. Architectures which do not have a m2p table, or which do not
146  * map it by default into guest address space, do not implement this command.
147  * arg == addr of xen_machphys_mapping_t.
148  */
149 #define XENMEM_machphys_mapping     12
150 struct xen_machphys_mapping {
151     unsigned long v_start, v_end; /* Start and end virtual addresses.   */
152     unsigned long max_mfn;        /* Maximum MFN that can be looked up. */
153 };
154 DEFINE_GUEST_HANDLE_STRUCT(xen_machphys_mapping_t);
155 
156 /*
157  * Sets the GPFN at which a particular page appears in the specified guest's
158  * pseudophysical address space.
159  * arg == addr of xen_add_to_physmap_t.
160  */
161 #define XENMEM_add_to_physmap      7
162 struct xen_add_to_physmap {
163     /* Which domain to change the mapping for. */
164     domid_t domid;
165 
166     /* Source mapping space. */
167 #define XENMAPSPACE_shared_info 0 /* shared info page */
168 #define XENMAPSPACE_grant_table 1 /* grant table page */
169     unsigned int space;
170 
171     /* Index into source mapping space. */
172     unsigned long idx;
173 
174     /* GPFN where the source mapping page should appear. */
175     unsigned long gpfn;
176 };
177 DEFINE_GUEST_HANDLE_STRUCT(xen_add_to_physmap);
178 
179 /*
180  * Translates a list of domain-specific GPFNs into MFNs. Returns a -ve error
181  * code on failure. This call only works for auto-translated guests.
182  */
183 #define XENMEM_translate_gpfn_list  8
184 struct xen_translate_gpfn_list {
185     /* Which domain to translate for? */
186     domid_t domid;
187 
188     /* Length of list. */
189     unsigned long nr_gpfns;
190 
191     /* List of GPFNs to translate. */
192     GUEST_HANDLE(ulong) gpfn_list;
193 
194     /*
195      * Output list to contain MFN translations. May be the same as the input
196      * list (in which case each input GPFN is overwritten with the output MFN).
197      */
198     GUEST_HANDLE(ulong) mfn_list;
199 };
200 DEFINE_GUEST_HANDLE_STRUCT(xen_translate_gpfn_list);
201 
202 /*
203  * Returns the pseudo-physical memory map as it was when the domain
204  * was started (specified by XENMEM_set_memory_map).
205  * arg == addr of struct xen_memory_map.
206  */
207 #define XENMEM_memory_map           9
208 struct xen_memory_map {
209     /*
210      * On call the number of entries which can be stored in buffer. On
211      * return the number of entries which have been stored in
212      * buffer.
213      */
214     unsigned int nr_entries;
215 
216     /*
217      * Entries in the buffer are in the same format as returned by the
218      * BIOS INT 0x15 EAX=0xE820 call.
219      */
220     GUEST_HANDLE(void) buffer;
221 };
222 DEFINE_GUEST_HANDLE_STRUCT(xen_memory_map);
223 
224 /*
225  * Returns the real physical memory map. Passes the same structure as
226  * XENMEM_memory_map.
227  * arg == addr of struct xen_memory_map.
228  */
229 #define XENMEM_machine_memory_map   10
230 
231 
232 /*
233  * Prevent the balloon driver from changing the memory reservation
234  * during a driver critical region.
235  */
236 extern spinlock_t xen_reservation_lock;
237 #endif /* __XEN_PUBLIC_MEMORY_H__ */
238