[deliverable/linux.git] / include / linux / virtio_config.h

#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>

/**
 * 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
 * @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.
 */
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);
	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 *names[]);
	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);
};

/* 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);
}

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);
	if (err < 0)
		return ERR_PTR(err);
	return vq;
}

/**
 * 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;
}

/* Memory accessors */
static inline u16 virtio16_to_cpu(struct virtio_device *vdev, __virtio16 val)
{
	return __virtio16_to_cpu(virtio_has_feature(vdev, VIRTIO_F_VERSION_1), val);
}

static inline __virtio16 cpu_to_virtio16(struct virtio_device *vdev, u16 val)
{
	return __cpu_to_virtio16(virtio_has_feature(vdev, VIRTIO_F_VERSION_1), val);
}

static inline u32 virtio32_to_cpu(struct virtio_device *vdev, __virtio32 val)
{
	return __virtio32_to_cpu(virtio_has_feature(vdev, VIRTIO_F_VERSION_1), val);
}

static inline __virtio32 cpu_to_virtio32(struct virtio_device *vdev, u32 val)
{
	return __cpu_to_virtio32(virtio_has_feature(vdev, VIRTIO_F_VERSION_1), val);
}

static inline u64 virtio64_to_cpu(struct virtio_device *vdev, __virtio64 val)
{
	return __virtio64_to_cpu(virtio_has_feature(vdev, VIRTIO_F_VERSION_1), val);
}

static inline __virtio64 cpu_to_virtio64(struct virtio_device *vdev, u64 val)
{
	return __cpu_to_virtio64(virtio_has_feature(vdev, VIRTIO_F_VERSION_1), 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)

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_cread_bytes(struct virtio_device *vdev,
				      unsigned int offset,
				      void *buf, size_t len)
{
	int i;

	for (i = 0; i < len; i++)
		vdev->config->get(vdev, offset + i, buf + i, 1);
}

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;
	vdev->config->get(vdev, offset, &ret, 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 */
Commit	Line	Data
ec3d41c4 RR	1	#ifndef _LINUX_VIRTIO_CONFIG_H
ec3d41c4 RR	2	#define _LINUX_VIRTIO_CONFIG_H
b4f68be6	3
d2a7ddda	4	#include <linux/err.h>
187f1882	5	#include <linux/bug.h>
72e61eb4	6	#include <linux/virtio.h>
eef960a0	7	#include <linux/virtio_byteorder.h>
607ca46e	8	#include <uapi/linux/virtio_config.h>
ec3d41c4 RR	9
	10	/**
	11	* virtio_config_ops - operations for configuring a virtio device
a586d4f6	12	* @get: read the value of a configuration field
ec3d41c4	13	* vdev: the virtio_device
a586d4f6	14	* offset: the offset of the configuration field
ec3d41c4	15	* buf: the buffer to write the field value into.
a586d4f6	16	* len: the length of the buffer
a586d4f6	17	* @set: write the value of a configuration field
ec3d41c4	18	* vdev: the virtio_device
a586d4f6	19	* offset: the offset of the configuration field
ec3d41c4	20	* buf: the buffer to read the field value from.
a586d4f6	21	* len: the length of the buffer
ec3d41c4 RR	22	* @get_status: read the status byte
	23	* vdev: the virtio_device
	24	* Returns the status byte
	25	* @set_status: write the status byte
	26	* vdev: the virtio_device
	27	* status: the new status byte
6e5aa7ef RR	28	* @reset: reset the device
	29	* vdev: the virtio device
	30	* After this, status and feature negotiation must be done again
e6af578c MT	31	* Device must not be reset from its vq/config callbacks, or in
e6af578c MT	32	* parallel with being added/removed.
d2a7ddda	33	* @find_vqs: find virtqueues and instantiate them.
ec3d41c4	34	* vdev: the virtio_device
d2a7ddda MT	35	* nvqs: the number of virtqueues to find
	36	* vqs: on success, includes new virtqueues
	37	* callbacks: array of callbacks, for each virtqueue
6457f126	38	* include a NULL entry for vqs that do not need a callback
d2a7ddda	39	* names: array of virtqueue names (mainly for debugging)
6457f126	40	* include a NULL entry for vqs unused by driver
d2a7ddda MT	41	* Returns 0 on success or error status
d2a7ddda MT	42	* @del_vqs: free virtqueues found by find_vqs().
c45a6816 RR	43	* @get_features: get the array of feature bits for this device.
	44	* vdev: the virtio_device
	45	* Returns the first 32 feature bits (all we currently need).
c624896e	46	* @finalize_features: confirm what device features we'll be using.
c45a6816	47	* vdev: the virtio_device
c624896e RR	48	* This gives the final feature bits for the device: it can change
c624896e RR	49	* the dev->feature bits if it wants.
5c609a5e	50	* Returns 0 on success or error status
66846048 RJ	51	* @bus_name: return the bus name associated with the device
	52	* vdev: the virtio_device
	53	* This returns a pointer to the bus name a la pci_name from which
	54	* the caller can then copy.
75a0a52b	55	* @set_vq_affinity: set the affinity for a virtqueue.
ec3d41c4	56	*/
d2a7ddda	57	typedef void vq_callback_t(struct virtqueue *);
1842f23c	58	struct virtio_config_ops {
a586d4f6	59	void (get)(struct virtio_device vdev, unsigned offset,
ec3d41c4	60	void *buf, unsigned len);
a586d4f6	61	void (set)(struct virtio_device vdev, unsigned offset,
ec3d41c4 RR	62	const void *buf, unsigned len);
	63	u8 (get_status)(struct virtio_device vdev);
	64	void (set_status)(struct virtio_device vdev, u8 status);
6e5aa7ef	65	void (reset)(struct virtio_device vdev);
d2a7ddda MT	66	int (find_vqs)(struct virtio_device , unsigned nvqs,
	67	struct virtqueue *vqs[],
	68	vq_callback_t *callbacks[],
	69	const char *names[]);
	70	void (del_vqs)(struct virtio_device );
d0254773	71	u64 (get_features)(struct virtio_device vdev);
5c609a5e	72	int (finalize_features)(struct virtio_device vdev);
66846048	73	const char (bus_name)(struct virtio_device *vdev);
75a0a52b	74	int (set_vq_affinity)(struct virtqueue vq, int cpu);
ec3d41c4 RR	75	};
ec3d41c4 RR	76
c45a6816 RR	77	/* If driver didn't advertise the feature, it will never appear. */
	78	void virtio_check_driver_offered_feature(const struct virtio_device *vdev,
	79	unsigned int fbit);
	80
	81	/**
d4024af5 MT	82	* __virtio_test_bit - helper to test feature bits. For use by transports.
	83	* Devices should normally use virtio_has_feature,
	84	* which includes more checks.
c45a6816 RR	85	* @vdev: the device
	86	* @fbit: the feature bit
	87	*/
d4024af5 MT	88	static inline bool __virtio_test_bit(const struct virtio_device *vdev,
	89	unsigned int fbit)
	90	{
	91	/* Did you forget to fix assumptions on max features? */
	92	if (__builtin_constant_p(fbit))
d0254773	93	BUILD_BUG_ON(fbit >= 64);
d4024af5	94	else
d0254773	95	BUG_ON(fbit >= 64);
d4024af5	96
d0254773	97	return vdev->features & BIT_ULL(fbit);
d4024af5 MT	98	}
	99
	100	/**
	101	* __virtio_set_bit - helper to set feature bits. For use by transports.
	102	* @vdev: the device
	103	* @fbit: the feature bit
	104	*/
	105	static inline void __virtio_set_bit(struct virtio_device *vdev,
	106	unsigned int fbit)
	107	{
	108	/* Did you forget to fix assumptions on max features? */
	109	if (__builtin_constant_p(fbit))
d0254773	110	BUILD_BUG_ON(fbit >= 64);
d4024af5	111	else
d0254773	112	BUG_ON(fbit >= 64);
d4024af5	113
d0254773	114	vdev->features \|= BIT_ULL(fbit);
d4024af5 MT	115	}
	116
	117	/**
	118	* __virtio_clear_bit - helper to clear feature bits. For use by transports.
	119	* @vdev: the device
	120	* @fbit: the feature bit
	121	*/
	122	static inline void __virtio_clear_bit(struct virtio_device *vdev,
c45a6816 RR	123	unsigned int fbit)
	124	{
	125	/* Did you forget to fix assumptions on max features? */
1765e3a4	126	if (__builtin_constant_p(fbit))
d0254773	127	BUILD_BUG_ON(fbit >= 64);
1765e3a4	128	else
d0254773	129	BUG_ON(fbit >= 64);
c45a6816	130
d0254773	131	vdev->features &= ~BIT_ULL(fbit);
d4024af5 MT	132	}
	133
	134	/**
	135	* virtio_has_feature - helper to determine if this device has this feature.
	136	* @vdev: the device
	137	* @fbit: the feature bit
	138	*/
	139	static inline bool virtio_has_feature(const struct virtio_device *vdev,
	140	unsigned int fbit)
	141	{
ee006b35 MM	142	if (fbit < VIRTIO_TRANSPORT_F_START)
	143	virtio_check_driver_offered_feature(vdev, fbit);
	144
d4024af5	145	return __virtio_test_bit(vdev, fbit);
c45a6816 RR	146	}
c45a6816 RR	147
d2a7ddda MT	148	static inline
	149	struct virtqueue virtio_find_single_vq(struct virtio_device vdev,
	150	vq_callback_t c, const char n)
	151	{
	152	vq_callback_t *callbacks[] = { c };
	153	const char *names[] = { n };
	154	struct virtqueue *vq;
	155	int err = vdev->config->find_vqs(vdev, 1, &vq, callbacks, names);
	156	if (err < 0)
	157	return ERR_PTR(err);
	158	return vq;
	159	}
66846048	160
3569db59 MT	161	/**
	162	* virtio_device_ready - enable vq use in probe function
	163	* @vdev: the device
	164	*
	165	* Driver must call this to use vqs in the probe function.
	166	*
	167	* Note: vqs are enabled automatically after probe returns.
	168	*/
	169	static inline
	170	void virtio_device_ready(struct virtio_device *dev)
	171	{
	172	unsigned status = dev->config->get_status(dev);
	173
	174	BUG_ON(status & VIRTIO_CONFIG_S_DRIVER_OK);
	175	dev->config->set_status(dev, status \| VIRTIO_CONFIG_S_DRIVER_OK);
	176	}
	177
66846048 RJ	178	static inline
	179	const char virtio_bus_name(struct virtio_device vdev)
	180	{
	181	if (!vdev->config->bus_name)
	182	return "virtio";
	183	return vdev->config->bus_name(vdev);
	184	}
	185
75a0a52b JW	186	/**
	187	* virtqueue_set_affinity - setting affinity for a virtqueue
	188	* @vq: the virtqueue
	189	* @cpu: the cpu no.
	190	*
	191	* Pay attention the function are best-effort: the affinity hint may not be set
	192	* due to config support, irq type and sharing.
	193	*
	194	*/
	195	static inline
	196	int virtqueue_set_affinity(struct virtqueue *vq, int cpu)
	197	{
	198	struct virtio_device *vdev = vq->vdev;
	199	if (vdev->config->set_vq_affinity)
	200	return vdev->config->set_vq_affinity(vq, cpu);
	201	return 0;
	202	}
	203
eef960a0 MT	204	/* Memory accessors */
	205	static inline u16 virtio16_to_cpu(struct virtio_device *vdev, __virtio16 val)
	206	{
	207	return __virtio16_to_cpu(virtio_has_feature(vdev, VIRTIO_F_VERSION_1), val);
	208	}
	209
	210	static inline __virtio16 cpu_to_virtio16(struct virtio_device *vdev, u16 val)
	211	{
	212	return __cpu_to_virtio16(virtio_has_feature(vdev, VIRTIO_F_VERSION_1), val);
	213	}
	214
	215	static inline u32 virtio32_to_cpu(struct virtio_device *vdev, __virtio32 val)
	216	{
	217	return __virtio32_to_cpu(virtio_has_feature(vdev, VIRTIO_F_VERSION_1), val);
	218	}
	219
	220	static inline __virtio32 cpu_to_virtio32(struct virtio_device *vdev, u32 val)
	221	{
	222	return __cpu_to_virtio32(virtio_has_feature(vdev, VIRTIO_F_VERSION_1), val);
	223	}
	224
	225	static inline u64 virtio64_to_cpu(struct virtio_device *vdev, __virtio64 val)
	226	{
	227	return __virtio64_to_cpu(virtio_has_feature(vdev, VIRTIO_F_VERSION_1), val);
	228	}
	229
	230	static inline __virtio64 cpu_to_virtio64(struct virtio_device *vdev, u64 val)
	231	{
	232	return __cpu_to_virtio64(virtio_has_feature(vdev, VIRTIO_F_VERSION_1), val);
	233	}
	234
0b90d062 RR	235	/* Config space accessors. */
	236	#define virtio_cread(vdev, structname, member, ptr) \
	237	do { \
	238	/* Must match the member's type, and be integer */ \
	239	if (!typecheck(typeof((((structname)0)->member)), (ptr))) \
	240	(*ptr) = 1; \
	241	\
	242	switch (sizeof(*ptr)) { \
	243	case 1: \
	244	*(ptr) = virtio_cread8(vdev, \
	245	offsetof(structname, member)); \
	246	break; \
	247	case 2: \
	248	*(ptr) = virtio_cread16(vdev, \
	249	offsetof(structname, member)); \
	250	break; \
	251	case 4: \
	252	*(ptr) = virtio_cread32(vdev, \
	253	offsetof(structname, member)); \
	254	break; \
	255	case 8: \
	256	*(ptr) = virtio_cread64(vdev, \
	257	offsetof(structname, member)); \
	258	break; \
	259	default: \
	260	BUG(); \
	261	} \
	262	} while(0)
	263
	264	/* Config space accessors. */
	265	#define virtio_cwrite(vdev, structname, member, ptr) \
	266	do { \
	267	/* Must match the member's type, and be integer */ \
	268	if (!typecheck(typeof((((structname)0)->member)), (ptr))) \
	269	BUG_ON((*ptr) == 1); \
	270	\
	271	switch (sizeof(*ptr)) { \
	272	case 1: \
	273	virtio_cwrite8(vdev, \
	274	offsetof(structname, member), \
	275	*(ptr)); \
	276	break; \
	277	case 2: \
	278	virtio_cwrite16(vdev, \
	279	offsetof(structname, member), \
	280	*(ptr)); \
	281	break; \
	282	case 4: \
	283	virtio_cwrite32(vdev, \
	284	offsetof(structname, member), \
	285	*(ptr)); \
	286	break; \
	287	case 8: \
	288	virtio_cwrite64(vdev, \
	289	offsetof(structname, member), \
	290	*(ptr)); \
	291	break; \
	292	default: \
	293	BUG(); \
	294	} \
	295	} while(0)
	296
	297	static inline u8 virtio_cread8(struct virtio_device *vdev, unsigned int offset)
	298	{
299	u8 ret;
300	vdev->config->get(vdev, offset, &ret, sizeof(ret));
301	return ret;
302	}
303
304	static inline void virtio_cread_bytes(struct virtio_device *vdev,
305	unsigned int offset,
306	void *buf, size_t len)
307	{
3d266782 MT	308	int i;
	309
	310	for (i = 0; i < len; i++)
	311	vdev->config->get(vdev, offset + i, buf + i, 1);
0b90d062 RR	312	}
	313
	314	static inline void virtio_cwrite8(struct virtio_device *vdev,
	315	unsigned int offset, u8 val)
	316	{
	317	vdev->config->set(vdev, offset, &val, sizeof(val));
	318	}
	319
	320	static inline u16 virtio_cread16(struct virtio_device *vdev,
	321	unsigned int offset)
	322	{
	323	u16 ret;
	324	vdev->config->get(vdev, offset, &ret, sizeof(ret));
92e6d743	325	return virtio16_to_cpu(vdev, (__force __virtio16)ret);
0b90d062 RR	326	}
	327
	328	static inline void virtio_cwrite16(struct virtio_device *vdev,
	329	unsigned int offset, u16 val)
	330	{
92e6d743	331	val = (__force u16)cpu_to_virtio16(vdev, val);
0b90d062 RR	332	vdev->config->set(vdev, offset, &val, sizeof(val));
	333	}
	334
	335	static inline u32 virtio_cread32(struct virtio_device *vdev,
	336	unsigned int offset)
	337	{
	338	u32 ret;
	339	vdev->config->get(vdev, offset, &ret, sizeof(ret));
92e6d743	340	return virtio32_to_cpu(vdev, (__force __virtio32)ret);
0b90d062 RR	341	}
	342
	343	static inline void virtio_cwrite32(struct virtio_device *vdev,
	344	unsigned int offset, u32 val)
	345	{
92e6d743	346	val = (__force u32)cpu_to_virtio32(vdev, val);
0b90d062 RR	347	vdev->config->set(vdev, offset, &val, sizeof(val));
	348	}
	349
	350	static inline u64 virtio_cread64(struct virtio_device *vdev,
	351	unsigned int offset)
	352	{
	353	u64 ret;
	354	vdev->config->get(vdev, offset, &ret, sizeof(ret));
92e6d743	355	return virtio64_to_cpu(vdev, (__force __virtio64)ret);
0b90d062 RR	356	}
	357
	358	static inline void virtio_cwrite64(struct virtio_device *vdev,
	359	unsigned int offset, u64 val)
	360	{
92e6d743	361	val = (__force u64)cpu_to_virtio64(vdev, val);
0b90d062 RR	362	vdev->config->set(vdev, offset, &val, sizeof(val));
	363	}
	364
	365	/* Conditional config space accessors. */
	366	#define virtio_cread_feature(vdev, fbit, structname, member, ptr) \
	367	({ \
	368	int _r = 0; \
	369	if (!virtio_has_feature(vdev, fbit)) \
	370	_r = -ENOENT; \
	371	else \
	372	virtio_cread((vdev), structname, member, ptr); \
	373	_r; \
	374	})
75a0a52b	375
ec3d41c4	376	#endif /* _LINUX_VIRTIO_CONFIG_H */