diff options
| -rw-r--r-- | src/libsystemd/bus-kernel.c | 6 | ||||
| -rw-r--r-- | src/libsystemd/kdbus.h | 52 |
2 files changed, 45 insertions, 13 deletions
diff --git a/src/libsystemd/bus-kernel.c b/src/libsystemd/bus-kernel.c index d69d6f3bc4..d3eeb52425 100644 --- a/src/libsystemd/bus-kernel.c +++ b/src/libsystemd/bus-kernel.c @@ -947,8 +947,8 @@ fail: } int bus_kernel_read_message(sd_bus *bus) { + struct kdbus_cmd_recv recv = {}; struct kdbus_msg *k; - uint64_t off; int r; assert(bus); @@ -957,14 +957,14 @@ int bus_kernel_read_message(sd_bus *bus) { if (r < 0) return r; - r = ioctl(bus->input_fd, KDBUS_CMD_MSG_RECV, &off); + r = ioctl(bus->input_fd, KDBUS_CMD_MSG_RECV, &recv); if (r < 0) { if (errno == EAGAIN) return 0; return -errno; } - k = (struct kdbus_msg *)((uint8_t *)bus->kdbus_buffer + off); + k = (struct kdbus_msg *)((uint8_t *)bus->kdbus_buffer + recv.offset); if (k->payload_type == KDBUS_PAYLOAD_DBUS) { r = bus_kernel_make_message(bus, k); diff --git a/src/libsystemd/kdbus.h b/src/libsystemd/kdbus.h index d2e4fd301b..10102d4335 100644 --- a/src/libsystemd/kdbus.h +++ b/src/libsystemd/kdbus.h @@ -349,6 +349,7 @@ enum kdbus_payload_type { * struct kdbus_msg - the representation of a kdbus message * @size: Total size of the message * @flags: Message flags (KDBUS_MSG_FLAGS_*) + * @priority: Message queue priority value * @dst_id: 64-bit ID of the destination connection * @src_id: 64-bit ID of the source connection * @payload_type: Payload type (KDBUS_PAYLOAD_*) @@ -366,6 +367,7 @@ enum kdbus_payload_type { struct kdbus_msg { __u64 size; __u64 flags; + __s64 priority; __u64 dst_id; __u64 src_id; __u64 payload_type; @@ -378,6 +380,42 @@ struct kdbus_msg { } __attribute__((aligned(8))); /** + * enum kdbus_recv_flags - flags for de-queuing messages + * @KDBUS_RECV_PEEK: Return the next queued message without + * actually de-queuing it, and without installing + * any file descriptors or other resources. It is + * usually used to determine the activating + * connection of a bus name. + * @KDBUS_RECV_DROP: Drop and free the next queued message and all + * its resources without actually receiving it. + * @KDBUS_RECV_USE_PRIORITY: Only de-queue messages with the specified or + * higher priority (lowest values); if not set, + * the priority value is ignored. + */ +enum kdbus_recv_flags { + KDBUS_RECV_PEEK = 1 << 0, + KDBUS_RECV_DROP = 1 << 1, + KDBUS_RECV_USE_PRIORITY = 1 << 2, +}; + +/** + * kdbus_cmd_recv - struct to de-queue a buffered message + * @flags: KDBUS_RECV_* flags + * @priority: Minimum priority of the messages to de-queue. Lowest + * values have the highest priority. + * @offset: Returned offset in the pool where the message is + * stored. The user must use KDBUS_CMD_FREE to free + * the allocated memory. + * + * This struct is used with the KDBUS_CMD_MSG_RECV ioctl. + */ +struct kdbus_cmd_recv { + __u64 flags; + __s64 priority; + __u64 offset; +} __attribute__((aligned(8))); + +/** * enum kdbus_policy_access_type - permissions of a policy record * @_KDBUS_POLICY_ACCESS_NULL: Uninitialized/invalid * @KDBUS_POLICY_ACCESS_USER: Grant access to a uid @@ -480,8 +518,7 @@ enum kdbus_attach_flags { * @id128: Unique 128-bit ID of the bus (kernel → userspace) * @items: A list of items * - * This struct is used with the KDBUS_CMD_HELLO ioctl. See the ioctl - * documentation for more information. + * This struct is used with the KDBUS_CMD_HELLO ioctl. */ struct kdbus_cmd_hello { __u64 size; @@ -700,11 +737,6 @@ struct kdbus_cmd_memfd_make { * placed in the receiver's pool. * @KDBUS_CMD_FREE: Release the allocated memory in the receiver's * pool. - * @KDBUS_CMD_DROP: Drop and free the next queued message and all - * its ressources without actually receiveing it. - * @KDBUS_CMD_SRC: Query the sender's connection ID of the next - * queued message, used to determine the activating - * connection of a bus name. * @KDBUS_CMD_NAME_ACQUIRE: Request a well-known bus name to associate with * the connection. Well-known names are used to * address a peer on the bus. @@ -759,10 +791,8 @@ enum kdbus_ioctl_type { KDBUS_CMD_BYEBYE = _IO (KDBUS_IOC_MAGIC, 0x31), KDBUS_CMD_MSG_SEND = _IOW (KDBUS_IOC_MAGIC, 0x40, struct kdbus_msg), - KDBUS_CMD_MSG_RECV = _IOR (KDBUS_IOC_MAGIC, 0x41, __u64 *), + KDBUS_CMD_MSG_RECV = _IOWR(KDBUS_IOC_MAGIC, 0x41, struct kdbus_cmd_recv), KDBUS_CMD_FREE = _IOW (KDBUS_IOC_MAGIC, 0x42, __u64 *), - KDBUS_CMD_MSG_DROP = _IO (KDBUS_IOC_MAGIC, 0x43), - KDBUS_CMD_MSG_SRC = _IOR (KDBUS_IOC_MAGIC, 0x44, __u64 *), KDBUS_CMD_NAME_ACQUIRE = _IOWR(KDBUS_IOC_MAGIC, 0x50, struct kdbus_cmd_name), KDBUS_CMD_NAME_RELEASE = _IOW (KDBUS_IOC_MAGIC, 0x51, struct kdbus_cmd_name), @@ -827,6 +857,8 @@ enum kdbus_ioctl_type { * @ENOENT: The name to query information about is currently not on * the bus. * @ENOMEM: Out of memory. + * @ENOMSG: The queue is not empty, but no message with a matching + * priority is currently queued. * @ENOSYS: The requested functionality is not available. * @ENOTSUPP: The feature negotiation failed, a not supported feature * was requested, or an unknown item type was received. |