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-rw-r--r--drivers/vhost/vhost.h360
1 files changed, 286 insertions, 74 deletions
diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h
index 42298cd23c73..4fe99765c5c7 100644
--- a/drivers/vhost/vhost.h
+++ b/drivers/vhost/vhost.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _VHOST_H
#define _VHOST_H
@@ -11,65 +12,98 @@
#include <linux/virtio_config.h>
#include <linux/virtio_ring.h>
#include <linux/atomic.h>
-
-struct vhost_device;
+#include <linux/vhost_iotlb.h>
+#include <linux/irqbypass.h>
+#include <linux/unroll.h>
struct vhost_work;
+struct vhost_task;
typedef void (*vhost_work_fn_t)(struct vhost_work *work);
+#define VHOST_WORK_QUEUED 1
struct vhost_work {
- struct list_head node;
- vhost_work_fn_t fn;
- wait_queue_head_t done;
- int flushing;
- unsigned queue_seq;
- unsigned done_seq;
+ struct llist_node node;
+ vhost_work_fn_t fn;
+ unsigned long flags;
+};
+
+struct vhost_worker;
+struct vhost_dev;
+
+struct vhost_worker_ops {
+ int (*create)(struct vhost_worker *worker, struct vhost_dev *dev,
+ const char *name);
+ void (*stop)(struct vhost_worker *worker);
+ void (*wakeup)(struct vhost_worker *worker);
+};
+
+struct vhost_worker {
+ struct task_struct *kthread_task;
+ struct vhost_task *vtsk;
+ struct vhost_dev *dev;
+ /* Used to serialize device wide flushing with worker swapping. */
+ struct mutex mutex;
+ struct llist_head work_list;
+ u64 kcov_handle;
+ u32 id;
+ int attachment_cnt;
+ bool killed;
+ const struct vhost_worker_ops *ops;
};
/* Poll a file (eventfd or socket) */
/* Note: there's nothing vhost specific about this structure. */
struct vhost_poll {
- poll_table table;
- wait_queue_head_t *wqh;
- wait_queue_t wait;
- struct vhost_work work;
- unsigned long mask;
- struct vhost_dev *dev;
+ poll_table table;
+ wait_queue_head_t *wqh;
+ wait_queue_entry_t wait;
+ struct vhost_work work;
+ __poll_t mask;
+ struct vhost_dev *dev;
+ struct vhost_virtqueue *vq;
};
-void vhost_work_init(struct vhost_work *work, vhost_work_fn_t fn);
-void vhost_work_queue(struct vhost_dev *dev, struct vhost_work *work);
-
void vhost_poll_init(struct vhost_poll *poll, vhost_work_fn_t fn,
- unsigned long mask, struct vhost_dev *dev);
+ __poll_t mask, struct vhost_dev *dev,
+ struct vhost_virtqueue *vq);
int vhost_poll_start(struct vhost_poll *poll, struct file *file);
void vhost_poll_stop(struct vhost_poll *poll);
-void vhost_poll_flush(struct vhost_poll *poll);
void vhost_poll_queue(struct vhost_poll *poll);
-void vhost_work_flush(struct vhost_dev *dev, struct vhost_work *work);
-long vhost_vring_ioctl(struct vhost_dev *d, int ioctl, void __user *argp);
+
+void vhost_work_init(struct vhost_work *work, vhost_work_fn_t fn);
+void vhost_dev_flush(struct vhost_dev *dev);
struct vhost_log {
u64 addr;
u64 len;
};
-struct vhost_virtqueue;
+enum vhost_uaddr_type {
+ VHOST_ADDR_DESC = 0,
+ VHOST_ADDR_AVAIL = 1,
+ VHOST_ADDR_USED = 2,
+ VHOST_NUM_ADDRS = 3,
+};
+
+struct vhost_vring_call {
+ struct eventfd_ctx *ctx;
+ struct irq_bypass_producer producer;
+};
/* The virtqueue structure describes a queue attached to a device. */
struct vhost_virtqueue {
struct vhost_dev *dev;
+ struct vhost_worker __rcu *worker;
/* The actual ring of buffers. */
struct mutex mutex;
unsigned int num;
- struct vring_desc __user *desc;
- struct vring_avail __user *avail;
- struct vring_used __user *used;
+ vring_desc_t __user *desc;
+ vring_avail_t __user *avail;
+ vring_used_t __user *used;
+ const struct vhost_iotlb_map *meta_iotlb[VHOST_NUM_ADDRS];
struct file *kick;
- struct file *call;
- struct file *error;
- struct eventfd_ctx *call_ctx;
+ struct vhost_vring_call call_ctx;
struct eventfd_ctx *error_ctx;
struct eventfd_ctx *log_ctx;
@@ -78,13 +112,19 @@ struct vhost_virtqueue {
/* The routine to call when the Guest pings us, or timeout. */
vhost_work_fn_t handle_kick;
- /* Last available index we saw. */
+ /* Last available index we saw.
+ * Values are limited to 0x7fff, and the high bit is used as
+ * a wrap counter when using VIRTIO_F_RING_PACKED. */
u16 last_avail_idx;
+ /* Next avail ring head when VIRTIO_F_IN_ORDER is negoitated */
+ u16 next_avail_head;
/* Caches available index value from user. */
u16 avail_idx;
- /* Last index we used. */
+ /* Last index we used.
+ * Values are limited to 0x7fff, and the high bit is used as
+ * a wrap counter when using VIRTIO_F_RING_PACKED. */
u16 last_used_idx;
/* Used flags */
@@ -101,92 +141,264 @@ struct vhost_virtqueue {
u64 log_addr;
struct iovec iov[UIO_MAXIOV];
+ struct iovec iotlb_iov[64];
struct iovec *indirect;
struct vring_used_elem *heads;
- /* We use a kind of RCU to access private pointer.
- * All readers access it from worker, which makes it possible to
- * flush the vhost_work instead of synchronize_rcu. Therefore readers do
- * not need to call rcu_read_lock/rcu_read_unlock: the beginning of
- * vhost_work execution acts instead of rcu_read_lock() and the end of
- * vhost_work execution acts instead of rcu_read_unlock().
- * Writers use virtqueue mutex. */
- void __rcu *private_data;
+ u16 *nheads;
+ /* Protected by virtqueue mutex. */
+ struct vhost_iotlb *umem;
+ struct vhost_iotlb *iotlb;
+ void *private_data;
+ VIRTIO_DECLARE_FEATURES(acked_features);
+ u64 acked_backend_features;
/* Log write descriptors */
void __user *log_base;
struct vhost_log *log;
+ struct iovec log_iov[64];
+
+ /* Ring endianness. Defaults to legacy native endianness.
+ * Set to true when starting a modern virtio device. */
+ bool is_le;
+#ifdef CONFIG_VHOST_CROSS_ENDIAN_LEGACY
+ /* Ring endianness requested by userspace for cross-endian support. */
+ bool user_be;
+#endif
+ u32 busyloop_timeout;
+};
+
+struct vhost_msg_node {
+ union {
+ struct vhost_msg msg;
+ struct vhost_msg_v2 msg_v2;
+ };
+ struct vhost_virtqueue *vq;
+ struct list_head node;
};
struct vhost_dev {
- /* Readers use RCU to access memory table pointer
- * log base pointer and features.
- * Writers use mutex below.*/
- struct vhost_memory __rcu *memory;
struct mm_struct *mm;
struct mutex mutex;
- unsigned acked_features;
struct vhost_virtqueue **vqs;
int nvqs;
- struct file *log_file;
struct eventfd_ctx *log_ctx;
- spinlock_t work_lock;
- struct list_head work_list;
- struct task_struct *worker;
+ struct vhost_iotlb *umem;
+ struct vhost_iotlb *iotlb;
+ spinlock_t iotlb_lock;
+ struct list_head read_list;
+ struct list_head pending_list;
+ wait_queue_head_t wait;
+ int iov_limit;
+ int weight;
+ int byte_weight;
+ struct xarray worker_xa;
+ bool use_worker;
+ /*
+ * If fork_owner is true we use vhost_tasks to create
+ * the worker so all settings/limits like cgroups, NPROC,
+ * scheduler, etc are inherited from the owner. If false,
+ * we use kthreads and only attach to the same cgroups
+ * as the owner for compat with older kernels.
+ * here we use true as default value.
+ * The default value is set by fork_from_owner_default
+ */
+ bool fork_owner;
+ int (*msg_handler)(struct vhost_dev *dev, u32 asid,
+ struct vhost_iotlb_msg *msg);
};
-long vhost_dev_init(struct vhost_dev *, struct vhost_virtqueue **vqs, int nvqs);
+bool vhost_exceeds_weight(struct vhost_virtqueue *vq, int pkts, int total_len);
+void vhost_dev_init(struct vhost_dev *, struct vhost_virtqueue **vqs,
+ int nvqs, int iov_limit, int weight, int byte_weight,
+ bool use_worker,
+ int (*msg_handler)(struct vhost_dev *dev, u32 asid,
+ struct vhost_iotlb_msg *msg));
long vhost_dev_set_owner(struct vhost_dev *dev);
bool vhost_dev_has_owner(struct vhost_dev *dev);
long vhost_dev_check_owner(struct vhost_dev *);
-struct vhost_memory *vhost_dev_reset_owner_prepare(void);
-void vhost_dev_reset_owner(struct vhost_dev *, struct vhost_memory *);
-void vhost_dev_cleanup(struct vhost_dev *, bool locked);
+struct vhost_iotlb *vhost_dev_reset_owner_prepare(void);
+void vhost_dev_reset_owner(struct vhost_dev *dev, struct vhost_iotlb *iotlb);
+void vhost_dev_cleanup(struct vhost_dev *);
void vhost_dev_stop(struct vhost_dev *);
long vhost_dev_ioctl(struct vhost_dev *, unsigned int ioctl, void __user *argp);
-long vhost_vring_ioctl(struct vhost_dev *d, int ioctl, void __user *argp);
-int vhost_vq_access_ok(struct vhost_virtqueue *vq);
-int vhost_log_access_ok(struct vhost_dev *);
+long vhost_vring_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *argp);
+long vhost_worker_ioctl(struct vhost_dev *dev, unsigned int ioctl,
+ void __user *argp);
+bool vhost_vq_access_ok(struct vhost_virtqueue *vq);
+bool vhost_log_access_ok(struct vhost_dev *);
+void vhost_clear_msg(struct vhost_dev *dev);
-int vhost_get_vq_desc(struct vhost_dev *, struct vhost_virtqueue *,
- struct iovec iov[], unsigned int iov_count,
+int vhost_get_vq_desc(struct vhost_virtqueue *,
+ struct iovec iov[], unsigned int iov_size,
unsigned int *out_num, unsigned int *in_num,
struct vhost_log *log, unsigned int *log_num);
-void vhost_discard_vq_desc(struct vhost_virtqueue *, int n);
-int vhost_init_used(struct vhost_virtqueue *);
+int vhost_get_vq_desc_n(struct vhost_virtqueue *vq,
+ struct iovec iov[], unsigned int iov_size,
+ unsigned int *out_num, unsigned int *in_num,
+ struct vhost_log *log, unsigned int *log_num,
+ unsigned int *ndesc);
+
+void vhost_discard_vq_desc(struct vhost_virtqueue *, int nbuf,
+ unsigned int ndesc);
+
+bool vhost_vq_work_queue(struct vhost_virtqueue *vq, struct vhost_work *work);
+bool vhost_vq_has_work(struct vhost_virtqueue *vq);
+bool vhost_vq_is_setup(struct vhost_virtqueue *vq);
+int vhost_vq_init_access(struct vhost_virtqueue *);
int vhost_add_used(struct vhost_virtqueue *, unsigned int head, int len);
int vhost_add_used_n(struct vhost_virtqueue *, struct vring_used_elem *heads,
- unsigned count);
+ u16 *nheads, unsigned count);
void vhost_add_used_and_signal(struct vhost_dev *, struct vhost_virtqueue *,
unsigned int id, int len);
void vhost_add_used_and_signal_n(struct vhost_dev *, struct vhost_virtqueue *,
- struct vring_used_elem *heads, unsigned count);
+ struct vring_used_elem *heads, u16 *nheads,
+ unsigned count);
void vhost_signal(struct vhost_dev *, struct vhost_virtqueue *);
void vhost_disable_notify(struct vhost_dev *, struct vhost_virtqueue *);
+bool vhost_vq_avail_empty(struct vhost_dev *, struct vhost_virtqueue *);
bool vhost_enable_notify(struct vhost_dev *, struct vhost_virtqueue *);
int vhost_log_write(struct vhost_virtqueue *vq, struct vhost_log *log,
- unsigned int log_num, u64 len);
+ unsigned int log_num, u64 len,
+ struct iovec *iov, int count);
+int vq_meta_prefetch(struct vhost_virtqueue *vq);
+
+struct vhost_msg_node *vhost_new_msg(struct vhost_virtqueue *vq, int type);
+void vhost_enqueue_msg(struct vhost_dev *dev,
+ struct list_head *head,
+ struct vhost_msg_node *node);
+struct vhost_msg_node *vhost_dequeue_msg(struct vhost_dev *dev,
+ struct list_head *head);
+void vhost_set_backend_features(struct vhost_dev *dev, u64 features);
+
+__poll_t vhost_chr_poll(struct file *file, struct vhost_dev *dev,
+ poll_table *wait);
+ssize_t vhost_chr_read_iter(struct vhost_dev *dev, struct iov_iter *to,
+ int noblock);
+ssize_t vhost_chr_write_iter(struct vhost_dev *dev,
+ struct iov_iter *from);
+int vhost_init_device_iotlb(struct vhost_dev *d);
+
+void vhost_iotlb_map_free(struct vhost_iotlb *iotlb,
+ struct vhost_iotlb_map *map);
#define vq_err(vq, fmt, ...) do { \
pr_debug(pr_fmt(fmt), ##__VA_ARGS__); \
if ((vq)->error_ctx) \
- eventfd_signal((vq)->error_ctx, 1);\
+ eventfd_signal((vq)->error_ctx);\
} while (0)
-enum {
- VHOST_FEATURES = (1ULL << VIRTIO_F_NOTIFY_ON_EMPTY) |
- (1ULL << VIRTIO_RING_F_INDIRECT_DESC) |
- (1ULL << VIRTIO_RING_F_EVENT_IDX) |
- (1ULL << VHOST_F_LOG_ALL),
-};
+#define VHOST_FEATURES \
+ VIRTIO_F_NOTIFY_ON_EMPTY, \
+ VIRTIO_RING_F_INDIRECT_DESC, \
+ VIRTIO_RING_F_EVENT_IDX, \
+ VHOST_F_LOG_ALL, \
+ VIRTIO_F_ANY_LAYOUT, \
+ VIRTIO_F_VERSION_1
+
+static inline u64 vhost_features_u64(const int *features, int size, int idx)
+{
+ u64 res = 0;
+
+ unrolled_count(VIRTIO_FEATURES_BITS)
+ for (int i = 0; i < size; ++i) {
+ int bit = features[i];
+
+ if (virtio_features_chk_bit(bit) && VIRTIO_U64(bit) == idx)
+ res |= VIRTIO_BIT(bit);
+ }
+ return res;
+}
-static inline int vhost_has_feature(struct vhost_dev *dev, int bit)
+#define VHOST_FEATURES_U64(features, idx) \
+ vhost_features_u64(features, ARRAY_SIZE(features), idx)
+
+#define DEFINE_VHOST_FEATURES_ARRAY_ENTRY(idx, features) \
+ [idx] = VHOST_FEATURES_U64(features, idx),
+
+#define DEFINE_VHOST_FEATURES_ARRAY(array, features) \
+ u64 array[VIRTIO_FEATURES_U64S] = { \
+ UNROLL(VIRTIO_FEATURES_U64S, \
+ DEFINE_VHOST_FEATURES_ARRAY_ENTRY, features) \
+ }
+
+/**
+ * vhost_vq_set_backend - Set backend.
+ *
+ * @vq Virtqueue.
+ * @private_data The private data.
+ *
+ * Context: Need to call with vq->mutex acquired.
+ */
+static inline void vhost_vq_set_backend(struct vhost_virtqueue *vq,
+ void *private_data)
{
- unsigned acked_features;
+ vq->private_data = private_data;
+}
- /* TODO: check that we are running from vhost_worker or dev mutex is
- * held? */
- acked_features = rcu_dereference_index_check(dev->acked_features, 1);
- return acked_features & (1 << bit);
+/**
+ * vhost_vq_get_backend - Get backend.
+ *
+ * @vq Virtqueue.
+ *
+ * Context: Need to call with vq->mutex acquired.
+ * Return: Private data previously set with vhost_vq_set_backend.
+ */
+static inline void *vhost_vq_get_backend(struct vhost_virtqueue *vq)
+{
+ return vq->private_data;
+}
+
+static inline bool vhost_has_feature(struct vhost_virtqueue *vq, int bit)
+{
+ return virtio_features_test_bit(vq->acked_features_array, bit);
+}
+
+static inline bool vhost_backend_has_feature(struct vhost_virtqueue *vq, int bit)
+{
+ return vq->acked_backend_features & (1ULL << bit);
+}
+
+#ifdef CONFIG_VHOST_CROSS_ENDIAN_LEGACY
+static inline bool vhost_is_little_endian(struct vhost_virtqueue *vq)
+{
+ return vq->is_le;
+}
+#else
+static inline bool vhost_is_little_endian(struct vhost_virtqueue *vq)
+{
+ return virtio_legacy_is_little_endian() || vq->is_le;
+}
+#endif
+
+/* Memory accessors */
+static inline u16 vhost16_to_cpu(struct vhost_virtqueue *vq, __virtio16 val)
+{
+ return __virtio16_to_cpu(vhost_is_little_endian(vq), val);
+}
+
+static inline __virtio16 cpu_to_vhost16(struct vhost_virtqueue *vq, u16 val)
+{
+ return __cpu_to_virtio16(vhost_is_little_endian(vq), val);
+}
+
+static inline u32 vhost32_to_cpu(struct vhost_virtqueue *vq, __virtio32 val)
+{
+ return __virtio32_to_cpu(vhost_is_little_endian(vq), val);
+}
+
+static inline __virtio32 cpu_to_vhost32(struct vhost_virtqueue *vq, u32 val)
+{
+ return __cpu_to_virtio32(vhost_is_little_endian(vq), val);
+}
+
+static inline u64 vhost64_to_cpu(struct vhost_virtqueue *vq, __virtio64 val)
+{
+ return __virtio64_to_cpu(vhost_is_little_endian(vq), val);
+}
+
+static inline __virtio64 cpu_to_vhost64(struct vhost_virtqueue *vq, u64 val)
+{
+ return __cpu_to_virtio64(vhost_is_little_endian(vq), val);
}
#endif
generated by cgit (git 2.34.1) at 2025-12-25 11:04:02 +0000