memory.h

   1 /*
   2  * Physical memory management API
   3  *
   4  * Copyright 2011 Red Hat, Inc. and/or its affiliates
   5  *
   6  * Authors:
   7  *  Avi Kivity <avi@redhat.com>
   8  *
   9  * This work is licensed under the terms of the GNU GPL, version 2.  See
  10  * the COPYING file in the top-level directory.
  11  *
  12  */
  13
  14 #ifndef MEMORY_H
  15 #define MEMORY_H
  16
  17 #ifndef CONFIG_USER_ONLY
  18
  19 #include <stdint.h>
  20 #include <stdbool.h>
  21 #include "qemu-common.h"
  22 #include "cpu-common.h"
  23 #include "targphys.h"
  24 #include "qemu-queue.h"
  25 #include "iorange.h"
  26
  27 typedef struct MemoryRegionOps MemoryRegionOps;
  28 typedef struct MemoryRegion MemoryRegion;
  29
  30 /* Must match *_DIRTY_FLAGS in cpu-all.h.  To be replaced with dynamic
  31  * registration.
  32  */
  33 #define DIRTY_MEMORY_VGA       0
  34 #define DIRTY_MEMORY_CODE      1
  35 #define DIRTY_MEMORY_MIGRATION 3
  36
  37 /*
  38  * Memory region callbacks
  39  */
  40 struct MemoryRegionOps {
  41     /* Read from the memory region. @addr is relative to @mr; @size is
  42      * in bytes. */
  43     uint64_t (*read)(void *opaque,
  44                      target_phys_addr_t addr,
  45                      unsigned size);
  46     /* Write to the memory region. @addr is relative to @mr; @size is
  47      * in bytes. */
  48     void (*write)(void *opaque,
  49                   target_phys_addr_t addr,
  50                   uint64_t data,
  51                   unsigned size);
  52
  53     enum device_endian endianness;
  54     /* Guest-visible constraints: */
  55     struct {
  56         /* If nonzero, specify bounds on access sizes beyond which a machine
  57          * check is thrown.
  58          */
  59         unsigned min_access_size;
  60         unsigned max_access_size;
  61         /* If true, unaligned accesses are supported.  Otherwise unaligned
  62          * accesses throw machine checks.
  63          */
  64          bool unaligned;
  65     } valid;
  66     /* Internal implementation constraints: */
  67     struct {
  68         /* If nonzero, specifies the minimum size implemented.  Smaller sizes
  69          * will be rounded upwards and a partial result will be returned.
  70          */
  71         unsigned min_access_size;
  72         /* If nonzero, specifies the maximum size implemented.  Larger sizes
  73          * will be done as a series of accesses with smaller sizes.
  74          */
  75         unsigned max_access_size;
  76         /* If true, unaligned accesses are supported.  Otherwise all accesses
  77          * are converted to (possibly multiple) naturally aligned accesses.
  78          */
  79          bool unaligned;
  80     } impl;
  81 };
  82
  83 typedef struct CoalescedMemoryRange CoalescedMemoryRange;
  84
  85 struct MemoryRegion {
  86     /* All fields are private - violators will be prosecuted */
  87     const MemoryRegionOps *ops;
  88     void *opaque;
  89     MemoryRegion *parent;
  90     uint64_t size;
  91     target_phys_addr_t addr;
  92     target_phys_addr_t offset;
  93     bool backend_registered;
  94     ram_addr_t ram_addr;
  95     IORange iorange;
  96     bool terminates;
  97     MemoryRegion *alias;
  98     target_phys_addr_t alias_offset;
  99     unsigned priority;
 100     bool may_overlap;
 101     QTAILQ_HEAD(subregions, MemoryRegion) subregions;
 102     QTAILQ_ENTRY(MemoryRegion) subregions_link;
 103     QTAILQ_HEAD(coalesced_ranges, CoalescedMemoryRange) coalesced;
 104     const char *name;
 105     uint8_t dirty_log_mask;
 106 };
 107
 108 /**
 109  * memory_region_init: Initialize a memory region
 110  *
 111  * The region typically acts as a container for other memory regions.  Us
 112  * memory_region_add_subregion() to add subregions.
 113  *
 114  * @mr: the #MemoryRegion to be initialized
 115  * @name: used for debugging; not visible to the user or ABI
 116  * @size: size of the region; any subregions beyond this size will be clipped
 117  */
 118 void memory_region_init(MemoryRegion *mr,
 119                         const char *name,
 120                         uint64_t size);
 121 /**
 122  * memory_region_init_io: Initialize an I/O memory region.
 123  *
 124  * Accesses into the region will be cause the callbacks in @ops to be called.
 125  * if @size is nonzero, subregions will be clipped to @size.
 126  *
 127  * @mr: the #MemoryRegion to be initialized.
 128  * @ops: a structure containing read and write callbacks to be used when
 129  *       I/O is performed on the region.
 130  * @opaque: passed to to the read and write callbacks of the @ops structure.
 131  * @name: used for debugging; not visible to the user or ABI
 132  * @size: size of the region.
 133  */
 134 void memory_region_init_io(MemoryRegion *mr,
 135                            const MemoryRegionOps *ops,
 136                            void *opaque,
 137                            const char *name,
 138                            uint64_t size);
 139
 140 /**
 141  * memory_region_init_ram:  Initialize RAM memory region.  Accesses into the
 142  *                          region will be modify memory directly.
 143  *
 144  * @mr: the #MemoryRegion to be initialized.
 145  * @dev: a device associated with the region; may be %NULL.
 146  * @name: the name of the region; the pair (@dev, @name) must be globally
 147  *        unique.  The name is part of the save/restore ABI and so cannot be
 148  *        changed.
 149  * @size: size of the region.
 150  */
 151 void memory_region_init_ram(MemoryRegion *mr,
 152                             DeviceState *dev, /* FIXME: layering violation */
 153                             const char *name,
 154                             uint64_t size);
 155
 156 /**
 157  * memory_region_init_ram:  Initialize RAM memory region from a user-provided.
 158  *                          pointer.  Accesses into the region will be modify
 159  *                          memory directly.
 160  *
 161  * @mr: the #MemoryRegion to be initialized.
 162  * @dev: a device associated with the region; may be %NULL.
 163  * @name: the name of the region; the pair (@dev, @name) must be globally
 164  *        unique.  The name is part of the save/restore ABI and so cannot be
 165  *        changed.
 166  * @size: size of the region.
 167  * @ptr: memory to be mapped; must contain at least @size bytes.
 168  */
 169 void memory_region_init_ram_ptr(MemoryRegion *mr,
 170                                 DeviceState *dev, /* FIXME: layering violation */
 171                                 const char *name,
 172                                 uint64_t size,
 173                                 void *ptr);
 174
 175 /**
 176  * memory_region_init_alias: Initialize a memory region that aliases all or a
 177  *                           part of another memory region.
 178  *
 179  * @mr: the #MemoryRegion to be initialized.
 180  * @name: used for debugging; not visible to the user or ABI
 181  * @orig: the region to be referenced; @mr will be equivalent to
 182  *        @orig between @offset and @offset + @size - 1.
 183  * @offset: start of the section in @orig to be referenced.
 184  * @size: size of the region.
 185  */
 186 void memory_region_init_alias(MemoryRegion *mr,
 187                               const char *name,
 188                               MemoryRegion *orig,
 189                               target_phys_addr_t offset,
 190                               uint64_t size);
 191 /**
 192  * memory_region_destroy: Destroy a memory region and relaim all resources.
 193  *
 194  * @mr: the region to be destroyed.  May not currently be a subregion
 195  *      (see memory_region_add_subregion()) or referenced in an alias
 196  *      (see memory_region_init_alias()).
 197  */
 198 void memory_region_destroy(MemoryRegion *mr);
 199
 200 /**
 201  * memory_region_size: get a memory region's size.
 202  *
 203  * @mr: the memory region being queried.
 204  */
 205 uint64_t memory_region_size(MemoryRegion *mr);
 206
 207 /**
 208  * memory_region_get_ram_ptr: Get a pointer into a RAM memory region.
 209  *
 210  * Returns a host pointer to a RAM memory region (created with
 211  * memory_region_init_ram() or memory_region_init_ram_ptr()).  Use with
 212  * care.
 213  *
 214  * @mr: the memory region being queried.
 215  */
 216 void *memory_region_get_ram_ptr(MemoryRegion *mr);
 217
 218 /**
 219  * memory_region_set_offset: Sets an offset to be added to MemoryRegionOps
 220  *                           callbacks.
 221  *
 222  * This function is deprecated and should not be used in new code.
 223  */
 224 void memory_region_set_offset(MemoryRegion *mr, target_phys_addr_t offset);
 225
 226 /**
 227  * memory_region_set_log: Turn dirty logging on or off for a region.
 228  *
 229  * Turns dirty logging on or off for a specified client (display, migration).
 230  * Only meaningful for RAM regions.
 231  *
 232  * @mr: the memory region being updated.
 233  * @log: whether dirty logging is to be enabled or disabled.
 234  * @client: the user of the logging information; %DIRTY_MEMORY_MIGRATION or
 235  *          %DIRTY_MEMORY_VGA.
 236  */
 237 void memory_region_set_log(MemoryRegion *mr, bool log, unsigned client);
 238
 239 /**
 240  * memory_region_get_dirty: Check whether a page is dirty for a specified
 241  *                          client.
 242  *
 243  * Checks whether a page has been written to since the last
 244  * call to memory_region_reset_dirty() with the same @client.  Dirty logging
 245  * must be enabled.
 246  *
 247  * @mr: the memory region being queried.
 248  * @addr: the address (relative to the start of the region) being queried.
 249  * @client: the user of the logging information; %DIRTY_MEMORY_MIGRATION or
 250  *          %DIRTY_MEMORY_VGA.
 251  */
 252 bool memory_region_get_dirty(MemoryRegion *mr, target_phys_addr_t addr,
 253                              unsigned client);
 254
 255 /**
 256  * memory_region_set_dirty: Mark a page as dirty in a memory region.
 257  *
 258  * Marks a page as dirty, after it has been dirtied outside guest code.
 259  *
 260  * @mr: the memory region being queried.
 261  * @addr: the address (relative to the start of the region) being dirtied.
 262  */
 263 void memory_region_set_dirty(MemoryRegion *mr, target_phys_addr_t addr);
 264
 265 /**
 266  * memory_region_sync_dirty_bitmap: Synchronize a region's dirty bitmap with
 267  *                                  any external TLBs (e.g. kvm)
 268  *
 269  * Flushes dirty information from accelerators such as kvm and vhost-net
 270  * and makes it available to users of the memory API.
 271  *
 272  * @mr: the region being flushed.
 273  */
 274 void memory_region_sync_dirty_bitmap(MemoryRegion *mr);
 275
 276 /**
 277  * memory_region_reset_dirty: Mark a range of pages as clean, for a specified
 278  *                            client.
 279  *
 280  * Marks a range of pages as no longer dirty.
 281  *
 282  * @mr: the region being updated.
 283  * @addr: the start of the subrange being cleaned.
 284  * @size: the size of the subrange being cleaned.
 285  * @client: the user of the logging information; %DIRTY_MEMORY_MIGRATION or
 286  *          %DIRTY_MEMORY_VGA.
 287  */
 288 void memory_region_reset_dirty(MemoryRegion *mr, target_phys_addr_t addr,
 289                                target_phys_addr_t size, unsigned client);
 290
 291 /**
 292  * memory_region_set_readonly: Turn a memory region read-only (or read-write)
 293  *
 294  * Allows a memory region to be marked as read-only (turning it into a ROM).
 295  * only useful on RAM regions.
 296  *
 297  * @mr: the region being updated.
 298  * @readonly: whether rhe region is to be ROM or RAM.
 299  */
 300 void memory_region_set_readonly(MemoryRegion *mr, bool readonly);
 301
 302 /**
 303  * memory_region_set_coalescing: Enable memory coalescing for the region.
 304  *
 305  * Enabled writes to a region to be queued for later processing. MMIO ->write
 306  * callbacks may be delayed until a non-coalesced MMIO is issued.
 307  * Only useful for IO regions.  Roughly similar to write-combining hardware.
 308  *
 309  * @mr: the memory region to be write coalesced
 310  */
 311 void memory_region_set_coalescing(MemoryRegion *mr);
 312
 313 /**
 314  * memory_region_add_coalescing: Enable memory coalescing for a sub-range of
 315  *                               a region.
 316  *
 317  * Like memory_region_set_coalescing(), but works on a sub-range of a region.
 318  * Multiple calls can be issued coalesced disjoint ranges.
 319  *
 320  * @mr: the memory region to be updated.
 321  * @offset: the start of the range within the region to be coalesced.
 322  * @size: the size of the subrange to be coalesced.
 323  */
 324 void memory_region_add_coalescing(MemoryRegion *mr,
 325                                   target_phys_addr_t offset,
 326                                   uint64_t size);
 327
 328 /**
 329  * memory_region_clear_coalescing: Disable MMIO coalescing for the region.
 330  *
 331  * Disables any coalescing caused by memory_region_set_coalescing() or
 332  * memory_region_add_coalescing().  Roughly equivalent to uncacheble memory
 333  * hardware.
 334  *
 335  * @mr: the memory region to be updated.
 336  */
 337 void memory_region_clear_coalescing(MemoryRegion *mr);
 338
 339 /**
 340  * memory_region_add_subregion: Add a sub-region to a container.
 341  *
 342  * Adds a sub-region at @offset.  The sub-region may not overlap with other
 343  * subregions (except for those explicitly marked as overlapping).  A region
 344  * may only be added once as a subregion (unless removed with
 345  * memory_region_del_subregion()); use memory_region_init_alias() if you
 346  * want a region to be a subregion in multiple locations.
 347  *
 348  * @mr: the region to contain the new subregion; must be a container
 349  *      initialized with memory_region_init().
 350  * @offset: the offset relative to @mr where @subregion is added.
 351  * @subregion: the subregion to be added.
 352  */
 353 void memory_region_add_subregion(MemoryRegion *mr,
 354                                  target_phys_addr_t offset,
 355                                  MemoryRegion *subregion);
 356 /**
 357  * memory_region_add_subregion: Add a sub-region to a container, with overlap.
 358  *
 359  * Adds a sub-region at @offset.  The sub-region may overlap with other
 360  * subregions.  Conflicts are resolved by having a higher @priority hide a
 361  * lower @priority. Subregions without priority are taken as @priority 0.
 362  * A region may only be added once as a subregion (unless removed with
 363  * memory_region_del_subregion()); use memory_region_init_alias() if you
 364  * want a region to be a subregion in multiple locations.
 365  *
 366  * @mr: the region to contain the new subregion; must be a container
 367  *      initialized with memory_region_init().
 368  * @offset: the offset relative to @mr where @subregion is added.
 369  * @subregion: the subregion to be added.
 370  * @priority: used for resolving overlaps; highest priority wins.
 371  */
 372 void memory_region_add_subregion_overlap(MemoryRegion *mr,
 373                                          target_phys_addr_t offset,
 374                                          MemoryRegion *subregion,
 375                                          unsigned priority);
 376 /**
 377  * memory_region_del_subregion: Remove a subregion.
 378  *
 379  * Removes a subregion from its container.
 380  *
 381  * @mr: the container to be updated.
 382  * @subregion: the region being removed; must be a current subregion of @mr.
 383  */
 384 void memory_region_del_subregion(MemoryRegion *mr,
 385                                  MemoryRegion *subregion);
 386
 387 #endif
 388
 389 #endif