Sets logging shared memory space.
When the back-end has VHOST_USER_PROTOCOL_F_LOG_SHMFD protocol feature,
the log memory fd is provided in the ancillary data of
VHOST_USER_SET_LOG_BASE message, the size and offset of shared memory
area provided in the message.
Signed-off-by: Laurent Vivier <lvivier(a)redhat.com>
---
util.h | 3 ++
vhost_user.c | 87 +++++++++++++++++++++++++++++++++++++++++++++++++++-
vhost_user.h | 3 ++
virtio.c | 74 ++++++++++++++++++++++++++++++++++++++++++--
virtio.h | 4 +++
5 files changed, 168 insertions(+), 3 deletions(-)
diff --git a/util.h b/util.h
index 3fa1d12544a0..d02333d5a88d 100644
--- a/util.h
+++ b/util.h
@@ -152,6 +152,9 @@ static inline void barrier(void) { __asm__ __volatile__(""
::: "memory"); }
#define smp_wmb() smp_mb_release()
#define smp_rmb() smp_mb_acquire()
+#define qatomic_or(ptr, n) \
+ ((void) __atomic_fetch_or(ptr, n, __ATOMIC_SEQ_CST))
+
#define NS_FN_STACK_SIZE (1024 * 1024) /* 1MiB */
int do_clone(int (*fn)(void *), char *stack_area, size_t stack_size, int flags,
diff --git a/vhost_user.c b/vhost_user.c
index ce4373d9eeca..c2fac58badf1 100644
--- a/vhost_user.c
+++ b/vhost_user.c
@@ -510,6 +510,12 @@ static bool vu_set_mem_table_exec(struct vu_dev *vdev,
*/
static void vu_close_log(struct vu_dev *vdev)
{
+ if (vdev->log_table) {
+ if (munmap(vdev->log_table, vdev->log_size) != 0)
+ die_perror("close log munmap() error");
+ vdev->log_table = NULL;
+ }
+
if (vdev->log_call_fd != -1) {
close(vdev->log_call_fd);
vdev->log_call_fd = -1;
@@ -520,7 +526,6 @@ static void vu_close_log(struct vu_dev *vdev)
* vu_log_kick() - Inform the front-end that the log has been modified
* @vdev: vhost-user device
*/
-/* cppcheck-suppress unusedFunction */
void vu_log_kick(const struct vu_dev *vdev)
{
if (vdev->log_call_fd != -1) {
@@ -532,6 +537,84 @@ void vu_log_kick(const struct vu_dev *vdev)
}
}
+
+/**
+ * vu_log_page() -- Update logging table
+ * @log_table: Base address of the logging table
+ * @page: Page number that has been updated
+ */
+/* NOLINTNEXTLINE(readability-non-const-parameter) */
+static void vu_log_page(uint8_t *log_table, uint64_t page)
+{
+ qatomic_or(&log_table[page / 8], 1 << (page % 8));
+}
+
+/**
+ * vu_log_write() -- Log memory write
+ * @dev: Vhost-user device
+ * @address: Memory address
+ * @length: Memory size
+ */
+void vu_log_write(const struct vu_dev *vdev, uint64_t address, uint64_t length)
+{
+ uint64_t page;
+
+ if (!vdev->log_table || !length ||
+ !vu_has_feature(vdev, VHOST_F_LOG_ALL))
+ return;
+
+ page = address / VHOST_LOG_PAGE;
+ while (page * VHOST_LOG_PAGE < address + length) {
+ vu_log_page(vdev->log_table, page);
+ page++;
+ }
+ vu_log_kick(vdev);
+}
+
+/**
+ * vu_set_log_base_exec() - Set the memory log base
+ * @vdev: vhost-user device
+ * @vmsg: vhost-user message
+ *
+ * Return: False as no reply is requested
+ *
+ * #syscalls:vu mmap munmap
+ */
+static bool vu_set_log_base_exec(struct vu_dev *vdev,
+ struct vhost_user_msg *msg)
+{
+ uint64_t log_mmap_size, log_mmap_offset;
+ void *base;
+ int fd;
+
+ if (msg->fd_num != 1 || msg->hdr.size != sizeof(msg->payload.log))
+ die("Invalid log_base message");
+
+ fd = msg->fds[0];
+ log_mmap_offset = msg->payload.log.mmap_offset;
+ log_mmap_size = msg->payload.log.mmap_size;
+
+ debug("Log mmap_offset: %"PRId64, log_mmap_offset);
+ debug("Log mmap_size: %"PRId64, log_mmap_size);
+
+ base = mmap(0, log_mmap_size, PROT_READ | PROT_WRITE, MAP_SHARED, fd,
+ log_mmap_offset);
+ close(fd);
+ if (base == MAP_FAILED)
+ die("log mmap error");
+
+ if (vdev->log_table)
+ munmap(vdev->log_table, vdev->log_size);
+
+ vdev->log_table = base;
+ vdev->log_size = log_mmap_size;
+
+ msg->hdr.size = sizeof(msg->payload.u64);
+ msg->fd_num = 0;
+
+ return true;
+}
+
/**
* vu_set_log_fd_exec() -- Set the eventfd used to report logging update
* @vdev: vhost-user device
@@ -915,6 +998,7 @@ void vu_init(struct ctx *c)
.notification = true,
};
}
+ c->vdev->log_table = NULL;
c->vdev->log_call_fd = -1;
}
@@ -984,6 +1068,7 @@ static bool (*vu_handle[VHOST_USER_MAX])(struct vu_dev *vdev,
[VHOST_USER_GET_QUEUE_NUM] = vu_get_queue_num_exec,
[VHOST_USER_SET_OWNER] = vu_set_owner_exec,
[VHOST_USER_SET_MEM_TABLE] = vu_set_mem_table_exec,
+ [VHOST_USER_SET_LOG_BASE] = vu_set_log_base_exec,
[VHOST_USER_SET_LOG_FD] = vu_set_log_fd_exec,
[VHOST_USER_SET_VRING_NUM] = vu_set_vring_num_exec,
[VHOST_USER_SET_VRING_ADDR] = vu_set_vring_addr_exec,
diff --git a/vhost_user.h b/vhost_user.h
index 2fc0342ff5ba..22a5d059073f 100644
--- a/vhost_user.h
+++ b/vhost_user.h
@@ -15,6 +15,7 @@
#include "iov.h"
#define VHOST_USER_F_PROTOCOL_FEATURES 30
+#define VHOST_LOG_PAGE 4096
#define VHOST_MEMORY_BASELINE_NREGIONS 8
@@ -241,5 +242,7 @@ void vu_print_capabilities(void);
void vu_init(struct ctx *c);
void vu_cleanup(struct vu_dev *vdev);
void vu_log_kick(const struct vu_dev *vdev);
+void vu_log_write(const struct vu_dev *vdev, uint64_t address,
+ uint64_t length);
void vu_control_handler(struct vu_dev *vdev, int fd, uint32_t events);
#endif /* VHOST_USER_H */
diff --git a/virtio.c b/virtio.c
index 52d5a4d4be52..13838586ad1a 100644
--- a/virtio.c
+++ b/virtio.c
@@ -81,6 +81,7 @@
#include "util.h"
#include "virtio.h"
+#include "vhost_user.h"
#define VIRTQUEUE_MAX_SIZE 1024
@@ -592,7 +593,72 @@ static inline void vring_used_write(const struct vu_dev *vdev,
struct vring_used *used = vq->vring.used;
used->ring[i] = *uelem;
- (void)vdev;
+ vu_log_write(vdev, vq->vring.log_guest_addr +
+ offsetof(struct vring_used, ring[i]),
+ sizeof(used->ring[i]));
+}
+
+/**
+ * vu_log_queue_fill() -- Log virtqueue memory update
+ * @dev: Vhost-user device
+ * @vq: Virtqueue
+ * @index: Descriptor ring index
+ * @len: Size of the element
+ */
+static void vu_log_queue_fill(const struct vu_dev *vdev, struct vu_virtq *vq,
+ unsigned int index, unsigned int len)
+{
+ struct vring_desc desc_buf[VIRTQUEUE_MAX_SIZE];
+ struct vring_desc *desc = vq->vring.desc;
+ unsigned int max, min;
+ unsigned num_bufs = 0;
+ uint64_t read_len;
+
+ if (!vdev->log_table || !len || !vu_has_feature(vdev, VHOST_F_LOG_ALL))
+ return;
+
+ max = vq->vring.num;
+
+ if (le16toh(desc[index].flags) & VRING_DESC_F_INDIRECT) {
+ unsigned int desc_len;
+ uint64_t desc_addr;
+
+ if (le32toh(desc[index].len) % sizeof(struct vring_desc))
+ die("Invalid size for indirect buffer table");
+
+ /* loop over the indirect descriptor table */
+ desc_addr = le64toh(desc[index].addr);
+ desc_len = le32toh(desc[index].len);
+ max = desc_len / sizeof(struct vring_desc);
+ read_len = desc_len;
+ desc = vu_gpa_to_va(vdev, &read_len, desc_addr);
+ if (desc && read_len != desc_len) {
+ /* Failed to use zero copy */
+ desc = NULL;
+ if (!virtqueue_read_indirect_desc(vdev, desc_buf,
+ desc_addr,
+ desc_len))
+ desc = desc_buf;
+ }
+
+ if (!desc)
+ die("Invalid indirect buffer table");
+
+ index = 0;
+ }
+
+ do {
+ if (++num_bufs > max)
+ die("Looped descriptor");
+
+ if (le16toh(desc[index].flags) & VRING_DESC_F_WRITE) {
+ min = MIN(le32toh(desc[index].len), len);
+ vu_log_write(vdev, le64toh(desc[index].addr), min);
+ len -= min;
+ }
+ } while (len > 0 &&
+ (virtqueue_read_next_desc(desc, index, max, &index) ==
+ VIRTQUEUE_READ_DESC_MORE));
}
@@ -614,6 +680,8 @@ void vu_queue_fill_by_index(const struct vu_dev *vdev, struct vu_virtq
*vq,
if (!vq->vring.avail)
return;
+ vu_log_queue_fill(vdev, vq, index, len);
+
idx = (idx + vq->used_idx) % vq->vring.num;
uelem.id = htole32(index);
@@ -646,7 +714,9 @@ static inline void vring_used_idx_set(const struct vu_dev *vdev,
struct vu_virtq *vq, uint16_t val)
{
vq->vring.used->idx = htole16(val);
- (void)vdev;
+ vu_log_write(vdev, vq->vring.log_guest_addr +
+ offsetof(struct vring_used, idx),
+ sizeof(vq->vring.used->idx));
vq->used_idx = val;
}
diff --git a/virtio.h b/virtio.h
index d95bb07bb913..f572341a0034 100644
--- a/virtio.h
+++ b/virtio.h
@@ -104,6 +104,8 @@ struct vu_dev_region {
* @features: Vhost-user features
* @protocol_features: Vhost-user protocol features
* @log_call_fd: Eventfd to report logging update
+ * @log_size: Size of the logging memory region
+ * @log_table: Base of the logging memory region
*/
struct vu_dev {
struct ctx *context;
@@ -113,6 +115,8 @@ struct vu_dev {
uint64_t features;
uint64_t protocol_features;
int log_call_fd;
+ uint64_t log_size;
+ uint8_t *log_table;
};
/**
--
2.47.1