| 1 | /* SPDX-License-Identifier: GPL-2.0 */ |
| 2 | #ifndef _LINUX_VIRTIO_CONFIG_H |
| 3 | #define _LINUX_VIRTIO_CONFIG_H |
| 4 | |
| 5 | #include <linux/err.h> |
| 6 | #include <linux/bug.h> |
| 7 | #include <linux/virtio.h> |
| 8 | #include <linux/virtio_byteorder.h> |
| 9 | #include <linux/compiler_types.h> |
| 10 | #include <uapi/linux/virtio_config.h> |
| 11 | |
| 12 | struct irq_affinity; |
| 13 | |
| 14 | struct virtio_shm_region { |
| 15 | u64 addr; |
| 16 | u64 len; |
| 17 | }; |
| 18 | |
| 19 | typedef void vq_callback_t(struct virtqueue *); |
| 20 | |
| 21 | /** |
| 22 | * struct virtio_config_ops - operations for configuring a virtio device |
| 23 | * Note: Do not assume that a transport implements all of the operations |
| 24 | * getting/setting a value as a simple read/write! Generally speaking, |
| 25 | * any of @get/@set, @get_status/@set_status, or @get_features/ |
| 26 | * @finalize_features are NOT safe to be called from an atomic |
| 27 | * context. |
| 28 | * @get: read the value of a configuration field |
| 29 | * vdev: the virtio_device |
| 30 | * offset: the offset of the configuration field |
| 31 | * buf: the buffer to write the field value into. |
| 32 | * len: the length of the buffer |
| 33 | * @set: write the value of a configuration field |
| 34 | * vdev: the virtio_device |
| 35 | * offset: the offset of the configuration field |
| 36 | * buf: the buffer to read the field value from. |
| 37 | * len: the length of the buffer |
| 38 | * @generation: config generation counter (optional) |
| 39 | * vdev: the virtio_device |
| 40 | * Returns the config generation counter |
| 41 | * @get_status: read the status byte |
| 42 | * vdev: the virtio_device |
| 43 | * Returns the status byte |
| 44 | * @set_status: write the status byte |
| 45 | * vdev: the virtio_device |
| 46 | * status: the new status byte |
| 47 | * @reset: reset the device |
| 48 | * vdev: the virtio device |
| 49 | * After this, status and feature negotiation must be done again |
| 50 | * Device must not be reset from its vq/config callbacks, or in |
| 51 | * parallel with being added/removed. |
| 52 | * @find_vqs: find virtqueues and instantiate them. |
| 53 | * vdev: the virtio_device |
| 54 | * nvqs: the number of virtqueues to find |
| 55 | * vqs: on success, includes new virtqueues |
| 56 | * callbacks: array of callbacks, for each virtqueue |
| 57 | * include a NULL entry for vqs that do not need a callback |
| 58 | * names: array of virtqueue names (mainly for debugging) |
| 59 | * include a NULL entry for vqs unused by driver |
| 60 | * Returns 0 on success or error status |
| 61 | * @del_vqs: free virtqueues found by find_vqs(). |
| 62 | * @synchronize_cbs: synchronize with the virtqueue callbacks (optional) |
| 63 | * The function guarantees that all memory operations on the |
| 64 | * queue before it are visible to the vring_interrupt() that is |
| 65 | * called after it. |
| 66 | * vdev: the virtio_device |
| 67 | * @get_features: get the array of feature bits for this device. |
| 68 | * vdev: the virtio_device |
| 69 | * Returns the first 64 feature bits (all we currently need). |
| 70 | * @finalize_features: confirm what device features we'll be using. |
| 71 | * vdev: the virtio_device |
| 72 | * This sends the driver feature bits to the device: it can change |
| 73 | * the dev->feature bits if it wants. |
| 74 | * Note that despite the name this can be called any number of |
| 75 | * times. |
| 76 | * Returns 0 on success or error status |
| 77 | * @bus_name: return the bus name associated with the device (optional) |
| 78 | * vdev: the virtio_device |
| 79 | * This returns a pointer to the bus name a la pci_name from which |
| 80 | * the caller can then copy. |
| 81 | * @set_vq_affinity: set the affinity for a virtqueue (optional). |
| 82 | * @get_vq_affinity: get the affinity for a virtqueue (optional). |
| 83 | * @get_shm_region: get a shared memory region based on the index. |
| 84 | * @disable_vq_and_reset: reset a queue individually (optional). |
| 85 | * vq: the virtqueue |
| 86 | * Returns 0 on success or error status |
| 87 | * disable_vq_and_reset will guarantee that the callbacks are disabled and |
| 88 | * synchronized. |
| 89 | * Except for the callback, the caller should guarantee that the vring is |
| 90 | * not accessed by any functions of virtqueue. |
| 91 | * @enable_vq_after_reset: enable a reset queue |
| 92 | * vq: the virtqueue |
| 93 | * Returns 0 on success or error status |
| 94 | * If disable_vq_and_reset is set, then enable_vq_after_reset must also be |
| 95 | * set. |
| 96 | */ |
| 97 | struct virtio_config_ops { |
| 98 | void (*get)(struct virtio_device *vdev, unsigned offset, |
| 99 | void *buf, unsigned len); |
| 100 | void (*set)(struct virtio_device *vdev, unsigned offset, |
| 101 | const void *buf, unsigned len); |
| 102 | u32 (*generation)(struct virtio_device *vdev); |
| 103 | u8 (*get_status)(struct virtio_device *vdev); |
| 104 | void (*set_status)(struct virtio_device *vdev, u8 status); |
| 105 | void (*reset)(struct virtio_device *vdev); |
| 106 | int (*find_vqs)(struct virtio_device *, unsigned nvqs, |
| 107 | struct virtqueue *vqs[], vq_callback_t *callbacks[], |
| 108 | const char * const names[], const bool *ctx, |
| 109 | struct irq_affinity *desc); |
| 110 | void (*del_vqs)(struct virtio_device *); |
| 111 | void (*synchronize_cbs)(struct virtio_device *); |
| 112 | u64 (*get_features)(struct virtio_device *vdev); |
| 113 | int (*finalize_features)(struct virtio_device *vdev); |
| 114 | const char *(*bus_name)(struct virtio_device *vdev); |
| 115 | int (*set_vq_affinity)(struct virtqueue *vq, |
| 116 | const struct cpumask *cpu_mask); |
| 117 | const struct cpumask *(*get_vq_affinity)(struct virtio_device *vdev, |
| 118 | int index); |
| 119 | bool (*get_shm_region)(struct virtio_device *vdev, |
| 120 | struct virtio_shm_region *region, u8 id); |
| 121 | int (*disable_vq_and_reset)(struct virtqueue *vq); |
| 122 | int (*enable_vq_after_reset)(struct virtqueue *vq); |
| 123 | }; |
| 124 | |
| 125 | /* If driver didn't advertise the feature, it will never appear. */ |
| 126 | void virtio_check_driver_offered_feature(const struct virtio_device *vdev, |
| 127 | unsigned int fbit); |
| 128 | |
| 129 | /** |
| 130 | * __virtio_test_bit - helper to test feature bits. For use by transports. |
| 131 | * Devices should normally use virtio_has_feature, |
| 132 | * which includes more checks. |
| 133 | * @vdev: the device |
| 134 | * @fbit: the feature bit |
| 135 | */ |
| 136 | static inline bool __virtio_test_bit(const struct virtio_device *vdev, |
| 137 | unsigned int fbit) |
| 138 | { |
| 139 | /* Did you forget to fix assumptions on max features? */ |
| 140 | if (__builtin_constant_p(fbit)) |
| 141 | BUILD_BUG_ON(fbit >= 64); |
| 142 | else |
| 143 | BUG_ON(fbit >= 64); |
| 144 | |
| 145 | return vdev->features & BIT_ULL(fbit); |
| 146 | } |
| 147 | |
| 148 | /** |
| 149 | * __virtio_set_bit - helper to set feature bits. For use by transports. |
| 150 | * @vdev: the device |
| 151 | * @fbit: the feature bit |
| 152 | */ |
| 153 | static inline void __virtio_set_bit(struct virtio_device *vdev, |
| 154 | unsigned int fbit) |
| 155 | { |
| 156 | /* Did you forget to fix assumptions on max features? */ |
| 157 | if (__builtin_constant_p(fbit)) |
| 158 | BUILD_BUG_ON(fbit >= 64); |
| 159 | else |
| 160 | BUG_ON(fbit >= 64); |
| 161 | |
| 162 | vdev->features |= BIT_ULL(fbit); |
| 163 | } |
| 164 | |
| 165 | /** |
| 166 | * __virtio_clear_bit - helper to clear feature bits. For use by transports. |
| 167 | * @vdev: the device |
| 168 | * @fbit: the feature bit |
| 169 | */ |
| 170 | static inline void __virtio_clear_bit(struct virtio_device *vdev, |
| 171 | unsigned int fbit) |
| 172 | { |
| 173 | /* Did you forget to fix assumptions on max features? */ |
| 174 | if (__builtin_constant_p(fbit)) |
| 175 | BUILD_BUG_ON(fbit >= 64); |
| 176 | else |
| 177 | BUG_ON(fbit >= 64); |
| 178 | |
| 179 | vdev->features &= ~BIT_ULL(fbit); |
| 180 | } |
| 181 | |
| 182 | /** |
| 183 | * virtio_has_feature - helper to determine if this device has this feature. |
| 184 | * @vdev: the device |
| 185 | * @fbit: the feature bit |
| 186 | */ |
| 187 | static inline bool virtio_has_feature(const struct virtio_device *vdev, |
| 188 | unsigned int fbit) |
| 189 | { |
| 190 | if (fbit < VIRTIO_TRANSPORT_F_START) |
| 191 | virtio_check_driver_offered_feature(vdev, fbit); |
| 192 | |
| 193 | return __virtio_test_bit(vdev, fbit); |
| 194 | } |
| 195 | |
| 196 | /** |
| 197 | * virtio_has_dma_quirk - determine whether this device has the DMA quirk |
| 198 | * @vdev: the device |
| 199 | */ |
| 200 | static inline bool virtio_has_dma_quirk(const struct virtio_device *vdev) |
| 201 | { |
| 202 | /* |
| 203 | * Note the reverse polarity of the quirk feature (compared to most |
| 204 | * other features), this is for compatibility with legacy systems. |
| 205 | */ |
| 206 | return !virtio_has_feature(vdev, VIRTIO_F_ACCESS_PLATFORM); |
| 207 | } |
| 208 | |
| 209 | static inline |
| 210 | struct virtqueue *virtio_find_single_vq(struct virtio_device *vdev, |
| 211 | vq_callback_t *c, const char *n) |
| 212 | { |
| 213 | vq_callback_t *callbacks[] = { c }; |
| 214 | const char *names[] = { n }; |
| 215 | struct virtqueue *vq; |
| 216 | int err = vdev->config->find_vqs(vdev, 1, &vq, callbacks, names, NULL, |
| 217 | NULL); |
| 218 | if (err < 0) |
| 219 | return ERR_PTR(err); |
| 220 | return vq; |
| 221 | } |
| 222 | |
| 223 | static inline |
| 224 | int virtio_find_vqs(struct virtio_device *vdev, unsigned nvqs, |
| 225 | struct virtqueue *vqs[], vq_callback_t *callbacks[], |
| 226 | const char * const names[], |
| 227 | struct irq_affinity *desc) |
| 228 | { |
| 229 | return vdev->config->find_vqs(vdev, nvqs, vqs, callbacks, names, NULL, desc); |
| 230 | } |
| 231 | |
| 232 | static inline |
| 233 | int virtio_find_vqs_ctx(struct virtio_device *vdev, unsigned nvqs, |
| 234 | struct virtqueue *vqs[], vq_callback_t *callbacks[], |
| 235 | const char * const names[], const bool *ctx, |
| 236 | struct irq_affinity *desc) |
| 237 | { |
| 238 | return vdev->config->find_vqs(vdev, nvqs, vqs, callbacks, names, ctx, |
| 239 | desc); |
| 240 | } |
| 241 | |
| 242 | /** |
| 243 | * virtio_synchronize_cbs - synchronize with virtqueue callbacks |
| 244 | * @dev: the virtio device |
| 245 | */ |
| 246 | static inline |
| 247 | void virtio_synchronize_cbs(struct virtio_device *dev) |
| 248 | { |
| 249 | if (dev->config->synchronize_cbs) { |
| 250 | dev->config->synchronize_cbs(dev); |
| 251 | } else { |
| 252 | /* |
| 253 | * A best effort fallback to synchronize with |
| 254 | * interrupts, preemption and softirq disabled |
| 255 | * regions. See comment above synchronize_rcu(). |
| 256 | */ |
| 257 | synchronize_rcu(); |
| 258 | } |
| 259 | } |
| 260 | |
| 261 | /** |
| 262 | * virtio_device_ready - enable vq use in probe function |
| 263 | * @dev: the virtio device |
| 264 | * |
| 265 | * Driver must call this to use vqs in the probe function. |
| 266 | * |
| 267 | * Note: vqs are enabled automatically after probe returns. |
| 268 | */ |
| 269 | static inline |
| 270 | void virtio_device_ready(struct virtio_device *dev) |
| 271 | { |
| 272 | unsigned status = dev->config->get_status(dev); |
| 273 | |
| 274 | WARN_ON(status & VIRTIO_CONFIG_S_DRIVER_OK); |
| 275 | |
| 276 | #ifdef CONFIG_VIRTIO_HARDEN_NOTIFICATION |
| 277 | /* |
| 278 | * The virtio_synchronize_cbs() makes sure vring_interrupt() |
| 279 | * will see the driver specific setup if it sees vq->broken |
| 280 | * as false (even if the notifications come before DRIVER_OK). |
| 281 | */ |
| 282 | virtio_synchronize_cbs(dev); |
| 283 | __virtio_unbreak_device(dev); |
| 284 | #endif |
| 285 | /* |
| 286 | * The transport should ensure the visibility of vq->broken |
| 287 | * before setting DRIVER_OK. See the comments for the transport |
| 288 | * specific set_status() method. |
| 289 | * |
| 290 | * A well behaved device will only notify a virtqueue after |
| 291 | * DRIVER_OK, this means the device should "see" the coherenct |
| 292 | * memory write that set vq->broken as false which is done by |
| 293 | * the driver when it sees DRIVER_OK, then the following |
| 294 | * driver's vring_interrupt() will see vq->broken as false so |
| 295 | * we won't lose any notification. |
| 296 | */ |
| 297 | dev->config->set_status(dev, status | VIRTIO_CONFIG_S_DRIVER_OK); |
| 298 | } |
| 299 | |
| 300 | static inline |
| 301 | const char *virtio_bus_name(struct virtio_device *vdev) |
| 302 | { |
| 303 | if (!vdev->config->bus_name) |
| 304 | return "virtio"; |
| 305 | return vdev->config->bus_name(vdev); |
| 306 | } |
| 307 | |
| 308 | /** |
| 309 | * virtqueue_set_affinity - setting affinity for a virtqueue |
| 310 | * @vq: the virtqueue |
| 311 | * @cpu_mask: the cpu mask |
| 312 | * |
| 313 | * Pay attention the function are best-effort: the affinity hint may not be set |
| 314 | * due to config support, irq type and sharing. |
| 315 | * |
| 316 | */ |
| 317 | static inline |
| 318 | int virtqueue_set_affinity(struct virtqueue *vq, const struct cpumask *cpu_mask) |
| 319 | { |
| 320 | struct virtio_device *vdev = vq->vdev; |
| 321 | if (vdev->config->set_vq_affinity) |
| 322 | return vdev->config->set_vq_affinity(vq, cpu_mask); |
| 323 | return 0; |
| 324 | } |
| 325 | |
| 326 | static inline |
| 327 | bool virtio_get_shm_region(struct virtio_device *vdev, |
| 328 | struct virtio_shm_region *region, u8 id) |
| 329 | { |
| 330 | if (!vdev->config->get_shm_region) |
| 331 | return false; |
| 332 | return vdev->config->get_shm_region(vdev, region, id); |
| 333 | } |
| 334 | |
| 335 | static inline bool virtio_is_little_endian(struct virtio_device *vdev) |
| 336 | { |
| 337 | return virtio_has_feature(vdev, VIRTIO_F_VERSION_1) || |
| 338 | virtio_legacy_is_little_endian(); |
| 339 | } |
| 340 | |
| 341 | /* Memory accessors */ |
| 342 | static inline u16 virtio16_to_cpu(struct virtio_device *vdev, __virtio16 val) |
| 343 | { |
| 344 | return __virtio16_to_cpu(virtio_is_little_endian(vdev), val); |
| 345 | } |
| 346 | |
| 347 | static inline __virtio16 cpu_to_virtio16(struct virtio_device *vdev, u16 val) |
| 348 | { |
| 349 | return __cpu_to_virtio16(virtio_is_little_endian(vdev), val); |
| 350 | } |
| 351 | |
| 352 | static inline u32 virtio32_to_cpu(struct virtio_device *vdev, __virtio32 val) |
| 353 | { |
| 354 | return __virtio32_to_cpu(virtio_is_little_endian(vdev), val); |
| 355 | } |
| 356 | |
| 357 | static inline __virtio32 cpu_to_virtio32(struct virtio_device *vdev, u32 val) |
| 358 | { |
| 359 | return __cpu_to_virtio32(virtio_is_little_endian(vdev), val); |
| 360 | } |
| 361 | |
| 362 | static inline u64 virtio64_to_cpu(struct virtio_device *vdev, __virtio64 val) |
| 363 | { |
| 364 | return __virtio64_to_cpu(virtio_is_little_endian(vdev), val); |
| 365 | } |
| 366 | |
| 367 | static inline __virtio64 cpu_to_virtio64(struct virtio_device *vdev, u64 val) |
| 368 | { |
| 369 | return __cpu_to_virtio64(virtio_is_little_endian(vdev), val); |
| 370 | } |
| 371 | |
| 372 | #define virtio_to_cpu(vdev, x) \ |
| 373 | _Generic((x), \ |
| 374 | __u8: (x), \ |
| 375 | __virtio16: virtio16_to_cpu((vdev), (x)), \ |
| 376 | __virtio32: virtio32_to_cpu((vdev), (x)), \ |
| 377 | __virtio64: virtio64_to_cpu((vdev), (x)) \ |
| 378 | ) |
| 379 | |
| 380 | #define cpu_to_virtio(vdev, x, m) \ |
| 381 | _Generic((m), \ |
| 382 | __u8: (x), \ |
| 383 | __virtio16: cpu_to_virtio16((vdev), (x)), \ |
| 384 | __virtio32: cpu_to_virtio32((vdev), (x)), \ |
| 385 | __virtio64: cpu_to_virtio64((vdev), (x)) \ |
| 386 | ) |
| 387 | |
| 388 | #define __virtio_native_type(structname, member) \ |
| 389 | typeof(virtio_to_cpu(NULL, ((structname*)0)->member)) |
| 390 | |
| 391 | /* Config space accessors. */ |
| 392 | #define virtio_cread(vdev, structname, member, ptr) \ |
| 393 | do { \ |
| 394 | typeof(((structname*)0)->member) virtio_cread_v; \ |
| 395 | \ |
| 396 | might_sleep(); \ |
| 397 | /* Sanity check: must match the member's type */ \ |
| 398 | typecheck(typeof(virtio_to_cpu((vdev), virtio_cread_v)), *(ptr)); \ |
| 399 | \ |
| 400 | switch (sizeof(virtio_cread_v)) { \ |
| 401 | case 1: \ |
| 402 | case 2: \ |
| 403 | case 4: \ |
| 404 | vdev->config->get((vdev), \ |
| 405 | offsetof(structname, member), \ |
| 406 | &virtio_cread_v, \ |
| 407 | sizeof(virtio_cread_v)); \ |
| 408 | break; \ |
| 409 | default: \ |
| 410 | __virtio_cread_many((vdev), \ |
| 411 | offsetof(structname, member), \ |
| 412 | &virtio_cread_v, \ |
| 413 | 1, \ |
| 414 | sizeof(virtio_cread_v)); \ |
| 415 | break; \ |
| 416 | } \ |
| 417 | *(ptr) = virtio_to_cpu(vdev, virtio_cread_v); \ |
| 418 | } while(0) |
| 419 | |
| 420 | /* Config space accessors. */ |
| 421 | #define virtio_cwrite(vdev, structname, member, ptr) \ |
| 422 | do { \ |
| 423 | typeof(((structname*)0)->member) virtio_cwrite_v = \ |
| 424 | cpu_to_virtio(vdev, *(ptr), ((structname*)0)->member); \ |
| 425 | \ |
| 426 | might_sleep(); \ |
| 427 | /* Sanity check: must match the member's type */ \ |
| 428 | typecheck(typeof(virtio_to_cpu((vdev), virtio_cwrite_v)), *(ptr)); \ |
| 429 | \ |
| 430 | vdev->config->set((vdev), offsetof(structname, member), \ |
| 431 | &virtio_cwrite_v, \ |
| 432 | sizeof(virtio_cwrite_v)); \ |
| 433 | } while(0) |
| 434 | |
| 435 | /* |
| 436 | * Nothing virtio-specific about these, but let's worry about generalizing |
| 437 | * these later. |
| 438 | */ |
| 439 | #define virtio_le_to_cpu(x) \ |
| 440 | _Generic((x), \ |
| 441 | __u8: (u8)(x), \ |
| 442 | __le16: (u16)le16_to_cpu(x), \ |
| 443 | __le32: (u32)le32_to_cpu(x), \ |
| 444 | __le64: (u64)le64_to_cpu(x) \ |
| 445 | ) |
| 446 | |
| 447 | #define virtio_cpu_to_le(x, m) \ |
| 448 | _Generic((m), \ |
| 449 | __u8: (x), \ |
| 450 | __le16: cpu_to_le16(x), \ |
| 451 | __le32: cpu_to_le32(x), \ |
| 452 | __le64: cpu_to_le64(x) \ |
| 453 | ) |
| 454 | |
| 455 | /* LE (e.g. modern) Config space accessors. */ |
| 456 | #define virtio_cread_le(vdev, structname, member, ptr) \ |
| 457 | do { \ |
| 458 | typeof(((structname*)0)->member) virtio_cread_v; \ |
| 459 | \ |
| 460 | might_sleep(); \ |
| 461 | /* Sanity check: must match the member's type */ \ |
| 462 | typecheck(typeof(virtio_le_to_cpu(virtio_cread_v)), *(ptr)); \ |
| 463 | \ |
| 464 | switch (sizeof(virtio_cread_v)) { \ |
| 465 | case 1: \ |
| 466 | case 2: \ |
| 467 | case 4: \ |
| 468 | vdev->config->get((vdev), \ |
| 469 | offsetof(structname, member), \ |
| 470 | &virtio_cread_v, \ |
| 471 | sizeof(virtio_cread_v)); \ |
| 472 | break; \ |
| 473 | default: \ |
| 474 | __virtio_cread_many((vdev), \ |
| 475 | offsetof(structname, member), \ |
| 476 | &virtio_cread_v, \ |
| 477 | 1, \ |
| 478 | sizeof(virtio_cread_v)); \ |
| 479 | break; \ |
| 480 | } \ |
| 481 | *(ptr) = virtio_le_to_cpu(virtio_cread_v); \ |
| 482 | } while(0) |
| 483 | |
| 484 | #define virtio_cwrite_le(vdev, structname, member, ptr) \ |
| 485 | do { \ |
| 486 | typeof(((structname*)0)->member) virtio_cwrite_v = \ |
| 487 | virtio_cpu_to_le(*(ptr), ((structname*)0)->member); \ |
| 488 | \ |
| 489 | might_sleep(); \ |
| 490 | /* Sanity check: must match the member's type */ \ |
| 491 | typecheck(typeof(virtio_le_to_cpu(virtio_cwrite_v)), *(ptr)); \ |
| 492 | \ |
| 493 | vdev->config->set((vdev), offsetof(structname, member), \ |
| 494 | &virtio_cwrite_v, \ |
| 495 | sizeof(virtio_cwrite_v)); \ |
| 496 | } while(0) |
| 497 | |
| 498 | |
| 499 | /* Read @count fields, @bytes each. */ |
| 500 | static inline void __virtio_cread_many(struct virtio_device *vdev, |
| 501 | unsigned int offset, |
| 502 | void *buf, size_t count, size_t bytes) |
| 503 | { |
| 504 | u32 old, gen = vdev->config->generation ? |
| 505 | vdev->config->generation(vdev) : 0; |
| 506 | int i; |
| 507 | |
| 508 | might_sleep(); |
| 509 | do { |
| 510 | old = gen; |
| 511 | |
| 512 | for (i = 0; i < count; i++) |
| 513 | vdev->config->get(vdev, offset + bytes * i, |
| 514 | buf + i * bytes, bytes); |
| 515 | |
| 516 | gen = vdev->config->generation ? |
| 517 | vdev->config->generation(vdev) : 0; |
| 518 | } while (gen != old); |
| 519 | } |
| 520 | |
| 521 | static inline void virtio_cread_bytes(struct virtio_device *vdev, |
| 522 | unsigned int offset, |
| 523 | void *buf, size_t len) |
| 524 | { |
| 525 | __virtio_cread_many(vdev, offset, buf, len, 1); |
| 526 | } |
| 527 | |
| 528 | static inline u8 virtio_cread8(struct virtio_device *vdev, unsigned int offset) |
| 529 | { |
| 530 | u8 ret; |
| 531 | |
| 532 | might_sleep(); |
| 533 | vdev->config->get(vdev, offset, &ret, sizeof(ret)); |
| 534 | return ret; |
| 535 | } |
| 536 | |
| 537 | static inline void virtio_cwrite8(struct virtio_device *vdev, |
| 538 | unsigned int offset, u8 val) |
| 539 | { |
| 540 | might_sleep(); |
| 541 | vdev->config->set(vdev, offset, &val, sizeof(val)); |
| 542 | } |
| 543 | |
| 544 | static inline u16 virtio_cread16(struct virtio_device *vdev, |
| 545 | unsigned int offset) |
| 546 | { |
| 547 | __virtio16 ret; |
| 548 | |
| 549 | might_sleep(); |
| 550 | vdev->config->get(vdev, offset, &ret, sizeof(ret)); |
| 551 | return virtio16_to_cpu(vdev, ret); |
| 552 | } |
| 553 | |
| 554 | static inline void virtio_cwrite16(struct virtio_device *vdev, |
| 555 | unsigned int offset, u16 val) |
| 556 | { |
| 557 | __virtio16 v; |
| 558 | |
| 559 | might_sleep(); |
| 560 | v = cpu_to_virtio16(vdev, val); |
| 561 | vdev->config->set(vdev, offset, &v, sizeof(v)); |
| 562 | } |
| 563 | |
| 564 | static inline u32 virtio_cread32(struct virtio_device *vdev, |
| 565 | unsigned int offset) |
| 566 | { |
| 567 | __virtio32 ret; |
| 568 | |
| 569 | might_sleep(); |
| 570 | vdev->config->get(vdev, offset, &ret, sizeof(ret)); |
| 571 | return virtio32_to_cpu(vdev, ret); |
| 572 | } |
| 573 | |
| 574 | static inline void virtio_cwrite32(struct virtio_device *vdev, |
| 575 | unsigned int offset, u32 val) |
| 576 | { |
| 577 | __virtio32 v; |
| 578 | |
| 579 | might_sleep(); |
| 580 | v = cpu_to_virtio32(vdev, val); |
| 581 | vdev->config->set(vdev, offset, &v, sizeof(v)); |
| 582 | } |
| 583 | |
| 584 | static inline u64 virtio_cread64(struct virtio_device *vdev, |
| 585 | unsigned int offset) |
| 586 | { |
| 587 | __virtio64 ret; |
| 588 | |
| 589 | __virtio_cread_many(vdev, offset, &ret, 1, sizeof(ret)); |
| 590 | return virtio64_to_cpu(vdev, ret); |
| 591 | } |
| 592 | |
| 593 | static inline void virtio_cwrite64(struct virtio_device *vdev, |
| 594 | unsigned int offset, u64 val) |
| 595 | { |
| 596 | __virtio64 v; |
| 597 | |
| 598 | might_sleep(); |
| 599 | v = cpu_to_virtio64(vdev, val); |
| 600 | vdev->config->set(vdev, offset, &v, sizeof(v)); |
| 601 | } |
| 602 | |
| 603 | /* Conditional config space accessors. */ |
| 604 | #define virtio_cread_feature(vdev, fbit, structname, member, ptr) \ |
| 605 | ({ \ |
| 606 | int _r = 0; \ |
| 607 | if (!virtio_has_feature(vdev, fbit)) \ |
| 608 | _r = -ENOENT; \ |
| 609 | else \ |
| 610 | virtio_cread((vdev), structname, member, ptr); \ |
| 611 | _r; \ |
| 612 | }) |
| 613 | |
| 614 | /* Conditional config space accessors. */ |
| 615 | #define virtio_cread_le_feature(vdev, fbit, structname, member, ptr) \ |
| 616 | ({ \ |
| 617 | int _r = 0; \ |
| 618 | if (!virtio_has_feature(vdev, fbit)) \ |
| 619 | _r = -ENOENT; \ |
| 620 | else \ |
| 621 | virtio_cread_le((vdev), structname, member, ptr); \ |
| 622 | _r; \ |
| 623 | }) |
| 624 | |
| 625 | #endif /* _LINUX_VIRTIO_CONFIG_H */ |