[PATCH 4/4] tools/virtio: Add virtqueue_use_wrap_counter support
Cristian Marussi
cristian.marussi at arm.com
Tue Feb 8 07:25:20 PST 2022
Added simplified missing headers for VRING_POLL_* macros and a definition
of virtqueue_use_wrap_counter API.
Add --wrap-counters option to virtio_test to be able to test the new
virtqueue_use_wrap_counter API.
Signed-off-by: Cristian Marussi <cristian.marussi at arm.com>
---
tools/virtio/linux/bitfield.h | 88 +++++++++++++++++++++++++++++++++++
tools/virtio/linux/bits.h | 36 ++++++++++++++
tools/virtio/linux/virtio.h | 33 +++++++++++++
tools/virtio/virtio_test.c | 35 ++++++++++++--
4 files changed, 189 insertions(+), 3 deletions(-)
create mode 100644 tools/virtio/linux/bitfield.h
create mode 100644 tools/virtio/linux/bits.h
diff --git a/tools/virtio/linux/bitfield.h b/tools/virtio/linux/bitfield.h
new file mode 100644
index 000000000000..43421844eecc
--- /dev/null
+++ b/tools/virtio/linux/bitfield.h
@@ -0,0 +1,88 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef _LINUX_BITFIELD_H
+#define _LINUX_BITFIELD_H
+
+#include <asm/byteorder.h>
+
+/*
+ * Bitfield access macros
+ *
+ * FIELD_{GET,PREP} macros take as first parameter shifted mask
+ * from which they extract the base mask and shift amount.
+ * Mask must be a compilation time constant.
+ *
+ * Example:
+ *
+ * #define REG_FIELD_A GENMASK(6, 0)
+ * #define REG_FIELD_B BIT(7)
+ * #define REG_FIELD_C GENMASK(15, 8)
+ * #define REG_FIELD_D GENMASK(31, 16)
+ *
+ * Get:
+ * a = FIELD_GET(REG_FIELD_A, reg);
+ * b = FIELD_GET(REG_FIELD_B, reg);
+ *
+ * Set:
+ * reg = FIELD_PREP(REG_FIELD_A, 1) |
+ * FIELD_PREP(REG_FIELD_B, 0) |
+ * FIELD_PREP(REG_FIELD_C, c) |
+ * FIELD_PREP(REG_FIELD_D, 0x40);
+ *
+ * Modify:
+ * reg &= ~REG_FIELD_C;
+ * reg |= FIELD_PREP(REG_FIELD_C, c);
+ */
+
+#define __bf_shf(x) (__builtin_ffsll(x) - 1)
+
+/**
+ * FIELD_MAX() - produce the maximum value representable by a field
+ * @_mask: shifted mask defining the field's length and position
+ *
+ * FIELD_MAX() returns the maximum value that can be held in the field
+ * specified by @_mask.
+ */
+#define FIELD_MAX(_mask) \
+ ({ \
+ (typeof(_mask))((_mask) >> __bf_shf(_mask)); \
+ })
+
+/**
+ * FIELD_FIT() - check if value fits in the field
+ * @_mask: shifted mask defining the field's length and position
+ * @_val: value to test against the field
+ *
+ * Return: true if @_val can fit inside @_mask, false if @_val is too big.
+ */
+#define FIELD_FIT(_mask, _val) \
+ ({ \
+ !((((typeof(_mask))_val) << __bf_shf(_mask)) & ~(_mask)); \
+ })
+
+/**
+ * FIELD_PREP() - prepare a bitfield element
+ * @_mask: shifted mask defining the field's length and position
+ * @_val: value to put in the field
+ *
+ * FIELD_PREP() masks and shifts up the value. The result should
+ * be combined with other fields of the bitfield using logical OR.
+ */
+#define FIELD_PREP(_mask, _val) \
+ ({ \
+ ((typeof(_mask))(_val) << __bf_shf(_mask)) & (_mask); \
+ })
+
+/**
+ * FIELD_GET() - extract a bitfield element
+ * @_mask: shifted mask defining the field's length and position
+ * @_reg: value of entire bitfield
+ *
+ * FIELD_GET() extracts the field specified by @_mask from the
+ * bitfield passed in as @_reg by masking and shifting it down.
+ */
+#define FIELD_GET(_mask, _reg) \
+ ({ \
+ (typeof(_mask))(((_reg) & (_mask)) >> __bf_shf(_mask)); \
+ })
+
+#endif
diff --git a/tools/virtio/linux/bits.h b/tools/virtio/linux/bits.h
new file mode 100644
index 000000000000..16f8fe32b0b3
--- /dev/null
+++ b/tools/virtio/linux/bits.h
@@ -0,0 +1,36 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __LINUX_BITS_H
+#define __LINUX_BITS_H
+
+#include <linux/const.h>
+#include <vdso/bits.h>
+#include <asm/bitsperlong.h>
+
+#define BIT_ULL(nr) (ULL(1) << (nr))
+#define BIT_MASK(nr) (UL(1) << ((nr) % BITS_PER_LONG))
+#define BIT_WORD(nr) ((nr) / BITS_PER_LONG)
+#define BIT_ULL_MASK(nr) (ULL(1) << ((nr) % BITS_PER_LONG_LONG))
+#define BIT_ULL_WORD(nr) ((nr) / BITS_PER_LONG_LONG)
+#define BITS_PER_BYTE 8
+
+/*
+ * Create a contiguous bitmask starting at bit position @l and ending at
+ * position @h. For example
+ * GENMASK_ULL(39, 21) gives us the 64bit vector 0x000000ffffe00000.
+ */
+
+#define GENMASK_INPUT_CHECK(h, l) 0
+
+#define __GENMASK(h, l) \
+ (((~UL(0)) - (UL(1) << (l)) + 1) & \
+ (~UL(0) >> (BITS_PER_LONG - 1 - (h))))
+#define GENMASK(h, l) \
+ (GENMASK_INPUT_CHECK(h, l) + __GENMASK(h, l))
+
+#define __GENMASK_ULL(h, l) \
+ (((~ULL(0)) - (ULL(1) << (l)) + 1) & \
+ (~ULL(0) >> (BITS_PER_LONG_LONG - 1 - (h))))
+#define GENMASK_ULL(h, l) \
+ (GENMASK_INPUT_CHECK(h, l) + __GENMASK_ULL(h, l))
+
+#endif /* __LINUX_BITS_H */
diff --git a/tools/virtio/linux/virtio.h b/tools/virtio/linux/virtio.h
index 9021187a66d9..0556e093f223 100644
--- a/tools/virtio/linux/virtio.h
+++ b/tools/virtio/linux/virtio.h
@@ -5,6 +5,8 @@
#include <linux/kernel.h>
#include <linux/spinlock.h>
+#define VIRTIO_CONFIG_S_DRIVER 2
+
typedef struct pm_message {
int event;
} pm_message_t;
@@ -48,9 +50,12 @@ struct device {
struct device_driver *driver;
};
+struct virtio_config_ops;
+
struct virtio_device {
struct device dev;
u64 features;
+ const struct virtio_config_ops *config;
struct list_head vqs;
spinlock_t vqs_list_lock;
};
@@ -65,6 +70,32 @@ struct virtqueue {
void *priv;
};
+struct virtio_config_ops {
+ void (*enable_cbs)(struct virtio_device *vdev);
+ void (*get)(struct virtio_device *vdev, unsigned int offset,
+ void *buf, unsigned int len);
+ void (*set)(struct virtio_device *vdev, unsigned int offset,
+ const void *buf, unsigned int 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 *vdev, unsigned int nvqs,
+ struct virtqueue *vqs[], void *callbacks[],
+ const char * const names[], const bool *ctx,
+ void *desc);
+ void (*del_vqs)(struct virtio_device *vdev);
+ 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,
+ const void *cpu_mask);
+ const void *(*get_vq_affinity)(struct virtio_device *vdev,
+ int index);
+ bool (*get_shm_region)(struct virtio_device *vdev,
+ void *region, u8 id);
+};
+
struct virtio_driver {
struct device_driver driver;
const struct virtio_device_id *id_table;
@@ -111,6 +142,8 @@ void virtqueue_disable_cb(struct virtqueue *vq);
bool virtqueue_enable_cb(struct virtqueue *vq);
bool virtqueue_enable_cb_delayed(struct virtqueue *vq);
+int virtqueue_use_wrap_counter(struct virtqueue *vq);
+
void *virtqueue_detach_unused_buf(struct virtqueue *vq);
struct virtqueue *vring_new_virtqueue(unsigned int index,
unsigned int num,
diff --git a/tools/virtio/virtio_test.c b/tools/virtio/virtio_test.c
index d9cb3d22d52f..deccd44e4739 100644
--- a/tools/virtio/virtio_test.c
+++ b/tools/virtio/virtio_test.c
@@ -21,6 +21,8 @@
#define RANDOM_BATCH -1
+static u8 virtio_test_device_status;
+
/* Unused */
void *__kmalloc_fake, *__kfree_ignore_start, *__kfree_ignore_end;
@@ -109,7 +111,7 @@ static void vq_reset(struct vq_info *info, int num, struct virtio_device *vdev)
info->vq->priv = info;
}
-static void vq_info_add(struct vdev_info *dev, int num)
+static void vq_info_add(struct vdev_info *dev, int num, bool use_wrap_counters)
{
struct vq_info *info = &dev->vqs[dev->nvqs];
int r;
@@ -119,12 +121,25 @@ static void vq_info_add(struct vdev_info *dev, int num)
r = posix_memalign(&info->ring, 4096, vring_size(num, 4096));
assert(r >= 0);
vq_reset(info, num, &dev->vdev);
+ if (use_wrap_counters) {
+ r = virtqueue_use_wrap_counter(info->vq);
+ assert(r == 0);
+ }
vhost_vq_setup(dev, info);
dev->fds[info->idx].fd = info->call;
dev->fds[info->idx].events = POLLIN;
dev->nvqs++;
}
+static u8 virtio_test_get_status(struct virtio_device *vdev)
+{
+ return virtio_test_device_status;
+}
+
+struct virtio_config_ops virtio_config_ops = {
+ .get_status = virtio_test_get_status,
+};
+
static void vdev_info_init(struct vdev_info* dev, unsigned long long features)
{
int r;
@@ -132,6 +147,8 @@ static void vdev_info_init(struct vdev_info* dev, unsigned long long features)
dev->vdriver.suppress_used_validation = false;
dev->vdev.dev.driver = &dev->vdriver.driver;
dev->vdev.features = features;
+ virtio_test_device_status = VIRTIO_CONFIG_S_DRIVER;
+ dev->vdev.config = &virtio_config_ops;
INIT_LIST_HEAD(&dev->vdev.vqs);
spin_lock_init(&dev->vdev.vqs_list_lock);
dev->buf_size = 1024;
@@ -316,6 +333,14 @@ const struct option longopts[] = {
.name = "no-delayed-interrupt",
.val = 'd',
},
+ {
+ .name = "wrap-counters",
+ .val = 'W',
+ },
+ {
+ .name = "no-wrap-counters",
+ .val = 'w',
+ },
{
.name = "batch",
.val = 'b',
@@ -337,6 +362,7 @@ static void help(void)
" [--no-event-idx]"
" [--no-virtio-1]"
" [--delayed-interrupt]"
+ " [--wrap-counters]"
" [--batch=random/N]"
" [--reset=N]"
"\n");
@@ -349,7 +375,7 @@ int main(int argc, char **argv)
(1ULL << VIRTIO_RING_F_EVENT_IDX) | (1ULL << VIRTIO_F_VERSION_1);
long batch = 1, reset = 0;
int o;
- bool delayed = false;
+ bool delayed = false, use_wrap_counters = false;
for (;;) {
o = getopt_long(argc, argv, optstring, longopts, NULL);
@@ -374,6 +400,9 @@ int main(int argc, char **argv)
case 'D':
delayed = true;
break;
+ case 'W':
+ use_wrap_counters = true;
+ break;
case 'b':
if (0 == strcmp(optarg, "random")) {
batch = RANDOM_BATCH;
@@ -400,7 +429,7 @@ int main(int argc, char **argv)
done:
vdev_info_init(&dev, features);
- vq_info_add(&dev, 256);
+ vq_info_add(&dev, 256, use_wrap_counters);
run_test(&dev, &dev.vqs[0], delayed, batch, reset, 0x100000);
return 0;
}
--
2.17.1
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