444 lines
13 KiB
C
444 lines
13 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
#ifndef _LINUX_VIRTIO_CONFIG_H
|
|
#define _LINUX_VIRTIO_CONFIG_H
|
|
|
|
#include <linux/err.h>
|
|
#include <linux/bug.h>
|
|
#include <linux/virtio.h>
|
|
#include <linux/virtio_byteorder.h>
|
|
#include <uapi/linux/virtio_config.h>
|
|
|
|
struct irq_affinity;
|
|
|
|
/**
|
|
* virtio_config_ops - operations for configuring a virtio device
|
|
* @get: read the value of a configuration field
|
|
* vdev: the virtio_device
|
|
* offset: the offset of the configuration field
|
|
* buf: the buffer to write the field value into.
|
|
* len: the length of the buffer
|
|
* @set: write the value of a configuration field
|
|
* vdev: the virtio_device
|
|
* offset: the offset of the configuration field
|
|
* buf: the buffer to read the field value from.
|
|
* len: the length of the buffer
|
|
* @generation: config generation counter
|
|
* vdev: the virtio_device
|
|
* Returns the config generation counter
|
|
* @get_status: read the status byte
|
|
* vdev: the virtio_device
|
|
* Returns the status byte
|
|
* @set_status: write the status byte
|
|
* vdev: the virtio_device
|
|
* status: the new status byte
|
|
* @reset: reset the device
|
|
* vdev: the virtio device
|
|
* After this, status and feature negotiation must be done again
|
|
* Device must not be reset from its vq/config callbacks, or in
|
|
* parallel with being added/removed.
|
|
* @find_vqs: find virtqueues and instantiate them.
|
|
* vdev: the virtio_device
|
|
* nvqs: the number of virtqueues to find
|
|
* vqs: on success, includes new virtqueues
|
|
* callbacks: array of callbacks, for each virtqueue
|
|
* include a NULL entry for vqs that do not need a callback
|
|
* names: array of virtqueue names (mainly for debugging)
|
|
* include a NULL entry for vqs unused by driver
|
|
* Returns 0 on success or error status
|
|
* @del_vqs: free virtqueues found by find_vqs().
|
|
* @get_features: get the array of feature bits for this device.
|
|
* vdev: the virtio_device
|
|
* Returns the first 32 feature bits (all we currently need).
|
|
* @finalize_features: confirm what device features we'll be using.
|
|
* vdev: the virtio_device
|
|
* This gives the final feature bits for the device: it can change
|
|
* the dev->feature bits if it wants.
|
|
* Returns 0 on success or error status
|
|
* @bus_name: return the bus name associated with the device
|
|
* vdev: the virtio_device
|
|
* This returns a pointer to the bus name a la pci_name from which
|
|
* the caller can then copy.
|
|
* @set_vq_affinity: set the affinity for a virtqueue.
|
|
* @get_vq_affinity: get the affinity for a virtqueue (optional).
|
|
*/
|
|
typedef void vq_callback_t(struct virtqueue *);
|
|
struct virtio_config_ops {
|
|
void (*get)(struct virtio_device *vdev, unsigned offset,
|
|
void *buf, unsigned len);
|
|
void (*set)(struct virtio_device *vdev, unsigned offset,
|
|
const void *buf, unsigned len);
|
|
u32 (*generation)(struct virtio_device *vdev);
|
|
u8 (*get_status)(struct virtio_device *vdev);
|
|
void (*set_status)(struct virtio_device *vdev, u8 status);
|
|
void (*reset)(struct virtio_device *vdev);
|
|
int (*find_vqs)(struct virtio_device *, unsigned nvqs,
|
|
struct virtqueue *vqs[], vq_callback_t *callbacks[],
|
|
const char * const names[], const bool *ctx,
|
|
struct irq_affinity *desc);
|
|
void (*del_vqs)(struct virtio_device *);
|
|
u64 (*get_features)(struct virtio_device *vdev);
|
|
int (*finalize_features)(struct virtio_device *vdev);
|
|
const char *(*bus_name)(struct virtio_device *vdev);
|
|
int (*set_vq_affinity)(struct virtqueue *vq, int cpu);
|
|
const struct cpumask *(*get_vq_affinity)(struct virtio_device *vdev,
|
|
int index);
|
|
};
|
|
|
|
/* If driver didn't advertise the feature, it will never appear. */
|
|
void virtio_check_driver_offered_feature(const struct virtio_device *vdev,
|
|
unsigned int fbit);
|
|
|
|
/**
|
|
* __virtio_test_bit - helper to test feature bits. For use by transports.
|
|
* Devices should normally use virtio_has_feature,
|
|
* which includes more checks.
|
|
* @vdev: the device
|
|
* @fbit: the feature bit
|
|
*/
|
|
static inline bool __virtio_test_bit(const struct virtio_device *vdev,
|
|
unsigned int fbit)
|
|
{
|
|
/* Did you forget to fix assumptions on max features? */
|
|
if (__builtin_constant_p(fbit))
|
|
BUILD_BUG_ON(fbit >= 64);
|
|
else
|
|
BUG_ON(fbit >= 64);
|
|
|
|
return vdev->features & BIT_ULL(fbit);
|
|
}
|
|
|
|
/**
|
|
* __virtio_set_bit - helper to set feature bits. For use by transports.
|
|
* @vdev: the device
|
|
* @fbit: the feature bit
|
|
*/
|
|
static inline void __virtio_set_bit(struct virtio_device *vdev,
|
|
unsigned int fbit)
|
|
{
|
|
/* Did you forget to fix assumptions on max features? */
|
|
if (__builtin_constant_p(fbit))
|
|
BUILD_BUG_ON(fbit >= 64);
|
|
else
|
|
BUG_ON(fbit >= 64);
|
|
|
|
vdev->features |= BIT_ULL(fbit);
|
|
}
|
|
|
|
/**
|
|
* __virtio_clear_bit - helper to clear feature bits. For use by transports.
|
|
* @vdev: the device
|
|
* @fbit: the feature bit
|
|
*/
|
|
static inline void __virtio_clear_bit(struct virtio_device *vdev,
|
|
unsigned int fbit)
|
|
{
|
|
/* Did you forget to fix assumptions on max features? */
|
|
if (__builtin_constant_p(fbit))
|
|
BUILD_BUG_ON(fbit >= 64);
|
|
else
|
|
BUG_ON(fbit >= 64);
|
|
|
|
vdev->features &= ~BIT_ULL(fbit);
|
|
}
|
|
|
|
/**
|
|
* virtio_has_feature - helper to determine if this device has this feature.
|
|
* @vdev: the device
|
|
* @fbit: the feature bit
|
|
*/
|
|
static inline bool virtio_has_feature(const struct virtio_device *vdev,
|
|
unsigned int fbit)
|
|
{
|
|
if (fbit < VIRTIO_TRANSPORT_F_START)
|
|
virtio_check_driver_offered_feature(vdev, fbit);
|
|
|
|
return __virtio_test_bit(vdev, fbit);
|
|
}
|
|
|
|
/**
|
|
* virtio_has_iommu_quirk - determine whether this device has the iommu quirk
|
|
* @vdev: the device
|
|
*/
|
|
static inline bool virtio_has_iommu_quirk(const struct virtio_device *vdev)
|
|
{
|
|
/*
|
|
* Note the reverse polarity of the quirk feature (compared to most
|
|
* other features), this is for compatibility with legacy systems.
|
|
*/
|
|
return !virtio_has_feature(vdev, VIRTIO_F_IOMMU_PLATFORM);
|
|
}
|
|
|
|
static inline
|
|
struct virtqueue *virtio_find_single_vq(struct virtio_device *vdev,
|
|
vq_callback_t *c, const char *n)
|
|
{
|
|
vq_callback_t *callbacks[] = { c };
|
|
const char *names[] = { n };
|
|
struct virtqueue *vq;
|
|
int err = vdev->config->find_vqs(vdev, 1, &vq, callbacks, names, NULL,
|
|
NULL);
|
|
if (err < 0)
|
|
return ERR_PTR(err);
|
|
return vq;
|
|
}
|
|
|
|
static inline
|
|
int virtio_find_vqs(struct virtio_device *vdev, unsigned nvqs,
|
|
struct virtqueue *vqs[], vq_callback_t *callbacks[],
|
|
const char * const names[],
|
|
struct irq_affinity *desc)
|
|
{
|
|
return vdev->config->find_vqs(vdev, nvqs, vqs, callbacks, names, NULL, desc);
|
|
}
|
|
|
|
static inline
|
|
int virtio_find_vqs_ctx(struct virtio_device *vdev, unsigned nvqs,
|
|
struct virtqueue *vqs[], vq_callback_t *callbacks[],
|
|
const char * const names[], const bool *ctx,
|
|
struct irq_affinity *desc)
|
|
{
|
|
return vdev->config->find_vqs(vdev, nvqs, vqs, callbacks, names, ctx,
|
|
desc);
|
|
}
|
|
|
|
/**
|
|
* virtio_device_ready - enable vq use in probe function
|
|
* @vdev: the device
|
|
*
|
|
* Driver must call this to use vqs in the probe function.
|
|
*
|
|
* Note: vqs are enabled automatically after probe returns.
|
|
*/
|
|
static inline
|
|
void virtio_device_ready(struct virtio_device *dev)
|
|
{
|
|
unsigned status = dev->config->get_status(dev);
|
|
|
|
BUG_ON(status & VIRTIO_CONFIG_S_DRIVER_OK);
|
|
dev->config->set_status(dev, status | VIRTIO_CONFIG_S_DRIVER_OK);
|
|
}
|
|
|
|
static inline
|
|
const char *virtio_bus_name(struct virtio_device *vdev)
|
|
{
|
|
if (!vdev->config->bus_name)
|
|
return "virtio";
|
|
return vdev->config->bus_name(vdev);
|
|
}
|
|
|
|
/**
|
|
* virtqueue_set_affinity - setting affinity for a virtqueue
|
|
* @vq: the virtqueue
|
|
* @cpu: the cpu no.
|
|
*
|
|
* Pay attention the function are best-effort: the affinity hint may not be set
|
|
* due to config support, irq type and sharing.
|
|
*
|
|
*/
|
|
static inline
|
|
int virtqueue_set_affinity(struct virtqueue *vq, int cpu)
|
|
{
|
|
struct virtio_device *vdev = vq->vdev;
|
|
if (vdev->config->set_vq_affinity)
|
|
return vdev->config->set_vq_affinity(vq, cpu);
|
|
return 0;
|
|
}
|
|
|
|
static inline bool virtio_is_little_endian(struct virtio_device *vdev)
|
|
{
|
|
return virtio_has_feature(vdev, VIRTIO_F_VERSION_1) ||
|
|
virtio_legacy_is_little_endian();
|
|
}
|
|
|
|
/* Memory accessors */
|
|
static inline u16 virtio16_to_cpu(struct virtio_device *vdev, __virtio16 val)
|
|
{
|
|
return __virtio16_to_cpu(virtio_is_little_endian(vdev), val);
|
|
}
|
|
|
|
static inline __virtio16 cpu_to_virtio16(struct virtio_device *vdev, u16 val)
|
|
{
|
|
return __cpu_to_virtio16(virtio_is_little_endian(vdev), val);
|
|
}
|
|
|
|
static inline u32 virtio32_to_cpu(struct virtio_device *vdev, __virtio32 val)
|
|
{
|
|
return __virtio32_to_cpu(virtio_is_little_endian(vdev), val);
|
|
}
|
|
|
|
static inline __virtio32 cpu_to_virtio32(struct virtio_device *vdev, u32 val)
|
|
{
|
|
return __cpu_to_virtio32(virtio_is_little_endian(vdev), val);
|
|
}
|
|
|
|
static inline u64 virtio64_to_cpu(struct virtio_device *vdev, __virtio64 val)
|
|
{
|
|
return __virtio64_to_cpu(virtio_is_little_endian(vdev), val);
|
|
}
|
|
|
|
static inline __virtio64 cpu_to_virtio64(struct virtio_device *vdev, u64 val)
|
|
{
|
|
return __cpu_to_virtio64(virtio_is_little_endian(vdev), val);
|
|
}
|
|
|
|
/* Config space accessors. */
|
|
#define virtio_cread(vdev, structname, member, ptr) \
|
|
do { \
|
|
/* Must match the member's type, and be integer */ \
|
|
if (!typecheck(typeof((((structname*)0)->member)), *(ptr))) \
|
|
(*ptr) = 1; \
|
|
\
|
|
switch (sizeof(*ptr)) { \
|
|
case 1: \
|
|
*(ptr) = virtio_cread8(vdev, \
|
|
offsetof(structname, member)); \
|
|
break; \
|
|
case 2: \
|
|
*(ptr) = virtio_cread16(vdev, \
|
|
offsetof(structname, member)); \
|
|
break; \
|
|
case 4: \
|
|
*(ptr) = virtio_cread32(vdev, \
|
|
offsetof(structname, member)); \
|
|
break; \
|
|
case 8: \
|
|
*(ptr) = virtio_cread64(vdev, \
|
|
offsetof(structname, member)); \
|
|
break; \
|
|
default: \
|
|
BUG(); \
|
|
} \
|
|
} while(0)
|
|
|
|
/* Config space accessors. */
|
|
#define virtio_cwrite(vdev, structname, member, ptr) \
|
|
do { \
|
|
/* Must match the member's type, and be integer */ \
|
|
if (!typecheck(typeof((((structname*)0)->member)), *(ptr))) \
|
|
BUG_ON((*ptr) == 1); \
|
|
\
|
|
switch (sizeof(*ptr)) { \
|
|
case 1: \
|
|
virtio_cwrite8(vdev, \
|
|
offsetof(structname, member), \
|
|
*(ptr)); \
|
|
break; \
|
|
case 2: \
|
|
virtio_cwrite16(vdev, \
|
|
offsetof(structname, member), \
|
|
*(ptr)); \
|
|
break; \
|
|
case 4: \
|
|
virtio_cwrite32(vdev, \
|
|
offsetof(structname, member), \
|
|
*(ptr)); \
|
|
break; \
|
|
case 8: \
|
|
virtio_cwrite64(vdev, \
|
|
offsetof(structname, member), \
|
|
*(ptr)); \
|
|
break; \
|
|
default: \
|
|
BUG(); \
|
|
} \
|
|
} while(0)
|
|
|
|
/* Read @count fields, @bytes each. */
|
|
static inline void __virtio_cread_many(struct virtio_device *vdev,
|
|
unsigned int offset,
|
|
void *buf, size_t count, size_t bytes)
|
|
{
|
|
u32 old, gen = vdev->config->generation ?
|
|
vdev->config->generation(vdev) : 0;
|
|
int i;
|
|
|
|
do {
|
|
old = gen;
|
|
|
|
for (i = 0; i < count; i++)
|
|
vdev->config->get(vdev, offset + bytes * i,
|
|
buf + i * bytes, bytes);
|
|
|
|
gen = vdev->config->generation ?
|
|
vdev->config->generation(vdev) : 0;
|
|
} while (gen != old);
|
|
}
|
|
|
|
static inline void virtio_cread_bytes(struct virtio_device *vdev,
|
|
unsigned int offset,
|
|
void *buf, size_t len)
|
|
{
|
|
__virtio_cread_many(vdev, offset, buf, len, 1);
|
|
}
|
|
|
|
static inline u8 virtio_cread8(struct virtio_device *vdev, unsigned int offset)
|
|
{
|
|
u8 ret;
|
|
vdev->config->get(vdev, offset, &ret, sizeof(ret));
|
|
return ret;
|
|
}
|
|
|
|
static inline void virtio_cwrite8(struct virtio_device *vdev,
|
|
unsigned int offset, u8 val)
|
|
{
|
|
vdev->config->set(vdev, offset, &val, sizeof(val));
|
|
}
|
|
|
|
static inline u16 virtio_cread16(struct virtio_device *vdev,
|
|
unsigned int offset)
|
|
{
|
|
u16 ret;
|
|
vdev->config->get(vdev, offset, &ret, sizeof(ret));
|
|
return virtio16_to_cpu(vdev, (__force __virtio16)ret);
|
|
}
|
|
|
|
static inline void virtio_cwrite16(struct virtio_device *vdev,
|
|
unsigned int offset, u16 val)
|
|
{
|
|
val = (__force u16)cpu_to_virtio16(vdev, val);
|
|
vdev->config->set(vdev, offset, &val, sizeof(val));
|
|
}
|
|
|
|
static inline u32 virtio_cread32(struct virtio_device *vdev,
|
|
unsigned int offset)
|
|
{
|
|
u32 ret;
|
|
vdev->config->get(vdev, offset, &ret, sizeof(ret));
|
|
return virtio32_to_cpu(vdev, (__force __virtio32)ret);
|
|
}
|
|
|
|
static inline void virtio_cwrite32(struct virtio_device *vdev,
|
|
unsigned int offset, u32 val)
|
|
{
|
|
val = (__force u32)cpu_to_virtio32(vdev, val);
|
|
vdev->config->set(vdev, offset, &val, sizeof(val));
|
|
}
|
|
|
|
static inline u64 virtio_cread64(struct virtio_device *vdev,
|
|
unsigned int offset)
|
|
{
|
|
u64 ret;
|
|
__virtio_cread_many(vdev, offset, &ret, 1, sizeof(ret));
|
|
return virtio64_to_cpu(vdev, (__force __virtio64)ret);
|
|
}
|
|
|
|
static inline void virtio_cwrite64(struct virtio_device *vdev,
|
|
unsigned int offset, u64 val)
|
|
{
|
|
val = (__force u64)cpu_to_virtio64(vdev, val);
|
|
vdev->config->set(vdev, offset, &val, sizeof(val));
|
|
}
|
|
|
|
/* Conditional config space accessors. */
|
|
#define virtio_cread_feature(vdev, fbit, structname, member, ptr) \
|
|
({ \
|
|
int _r = 0; \
|
|
if (!virtio_has_feature(vdev, fbit)) \
|
|
_r = -ENOENT; \
|
|
else \
|
|
virtio_cread((vdev), structname, member, ptr); \
|
|
_r; \
|
|
})
|
|
|
|
#endif /* _LINUX_VIRTIO_CONFIG_H */
|