Editing: io_uring.h

/* SPDX-License-Identifier: (GPL-2.0 WITH Linux-syscall-note) OR MIT */ /* * Header file for the io_uring interface. * * Copyright (C) 2019 Jens Axboe * Copyright (C) 2019 Christoph Hellwig */ #ifndef LINUX_IO_URING_H #define LINUX_IO_URING_H #include <linux/fs.h> #include <linux/types.h> /* * this file is shared with liburing and that has to autodetect * if linux/time_types.h is available or not, it can * define UAPI_LINUX_IO_URING_H_SKIP_LINUX_TIME_TYPES_H * if linux/time_types.h is not available */ #ifndef UAPI_LINUX_IO_URING_H_SKIP_LINUX_TIME_TYPES_H #include <linux/time_types.h> #endif #ifdef __cplusplus extern "C" { #endif /* * IO submission data structure (Submission Queue Entry) */ struct io_uring_sqe { __u8 opcode; /* type of operation for this sqe */ __u8 flags; /* IOSQE_ flags */ __u16 ioprio; /* ioprio for the request */ __s32 fd; /* file descriptor to do IO on */ union { __u64 off; /* offset into file */ __u64 addr2; struct { __u32 cmd_op; __u32 __pad1; }; }; union { __u64 addr; /* pointer to buffer or iovecs */ __u64 splice_off_in; struct { __u32 level; __u32 optname; }; }; __u32 len; /* buffer size or number of iovecs */ union { __kernel_rwf_t rw_flags; __u32 fsync_flags; __u16 poll_events; /* compatibility */ __u32 poll32_events; /* word-reversed for BE */ __u32 sync_range_flags; __u32 msg_flags; __u32 timeout_flags; __u32 accept_flags; __u32 cancel_flags; __u32 open_flags; __u32 statx_flags; __u32 fadvise_advice; __u32 splice_flags; __u32 rename_flags; __u32 unlink_flags; __u32 hardlink_flags; __u32 xattr_flags; __u32 msg_ring_flags; __u32 uring_cmd_flags; __u32 waitid_flags; __u32 futex_flags; __u32 install_fd_flags; }; __u64 user_data; /* data to be passed back at completion time */ /* pack this to avoid bogus arm OABI complaints */ union { /* index into fixed buffers, if used */ __u16 buf_index; /* for grouped buffer selection */ __u16 buf_group; } __attribute__((packed)); /* personality to use, if used */ __u16 personality; union { __s32 splice_fd_in; __u32 file_index; __u32 optlen; struct { __u16 addr_len; __u16 __pad3[1]; }; }; union { struct { __u64 addr3; __u64 __pad2[1]; }; __u64 optval; /* * If the ring is initialized with IORING_SETUP_SQE128, then * this field is used for 80 bytes of arbitrary command data */ __u8 cmd[0]; }; }; /* * If sqe->file_index is set to this for opcodes that instantiate a new * direct descriptor (like openat/openat2/accept), then io_uring will allocate * an available direct descriptor instead of having the application pass one * in. The picked direct descriptor will be returned in cqe->res, or -ENFILE * if the space is full. */ #define IORING_FILE_INDEX_ALLOC (~0U) enum { IOSQE_FIXED_FILE_BIT, IOSQE_IO_DRAIN_BIT, IOSQE_IO_LINK_BIT, IOSQE_IO_HARDLINK_BIT, IOSQE_ASYNC_BIT, IOSQE_BUFFER_SELECT_BIT, IOSQE_CQE_SKIP_SUCCESS_BIT, }; /* * sqe->flags */ /* use fixed fileset */ #define IOSQE_FIXED_FILE (1U << IOSQE_FIXED_FILE_BIT) /* issue after inflight IO */ #define IOSQE_IO_DRAIN (1U << IOSQE_IO_DRAIN_BIT) /* links next sqe */ #define IOSQE_IO_LINK (1U << IOSQE_IO_LINK_BIT) /* like LINK, but stronger */ #define IOSQE_IO_HARDLINK (1U << IOSQE_IO_HARDLINK_BIT) /* always go async */ #define IOSQE_ASYNC (1U << IOSQE_ASYNC_BIT) /* select buffer from sqe->buf_group */ #define IOSQE_BUFFER_SELECT (1U << IOSQE_BUFFER_SELECT_BIT) /* don't post CQE if request succeeded */ #define IOSQE_CQE_SKIP_SUCCESS (1U << IOSQE_CQE_SKIP_SUCCESS_BIT) /* * io_uring_setup() flags */ #define IORING_SETUP_IOPOLL (1U << 0) /* io_context is polled */ #define IORING_SETUP_SQPOLL (1U << 1) /* SQ poll thread */ #define IORING_SETUP_SQ_AFF (1U << 2) /* sq_thread_cpu is valid */ #define IORING_SETUP_CQSIZE (1U << 3) /* app defines CQ size */ #define IORING_SETUP_CLAMP (1U << 4) /* clamp SQ/CQ ring sizes */ #define IORING_SETUP_ATTACH_WQ (1U << 5) /* attach to existing wq */ #define IORING_SETUP_R_DISABLED (1U << 6) /* start with ring disabled */ #define IORING_SETUP_SUBMIT_ALL (1U << 7) /* continue submit on error */ /* * Cooperative task running. When requests complete, they often require * forcing the submitter to transition to the kernel to complete. If this * flag is set, work will be done when the task transitions anyway, rather * than force an inter-processor interrupt reschedule. This avoids interrupting * a task running in userspace, and saves an IPI. */ #define IORING_SETUP_COOP_TASKRUN (1U << 8) /* * If COOP_TASKRUN is set, get notified if task work is available for * running and a kernel transition would be needed to run it. This sets * IORING_SQ_TASKRUN in the sq ring flags. Not valid with COOP_TASKRUN. */ #define IORING_SETUP_TASKRUN_FLAG (1U << 9) #define IORING_SETUP_SQE128 (1U << 10) /* SQEs are 128 byte */ #define IORING_SETUP_CQE32 (1U << 11) /* CQEs are 32 byte */ /* * Only one task is allowed to submit requests */ #define IORING_SETUP_SINGLE_ISSUER (1U << 12) /* * Defer running task work to get events. * Rather than running bits of task work whenever the task transitions * try to do it just before it is needed. */ #define IORING_SETUP_DEFER_TASKRUN (1U << 13) /* * Application provides the memory for the rings */ #define IORING_SETUP_NO_MMAP (1U << 14) /* * Register the ring fd in itself for use with * IORING_REGISTER_USE_REGISTERED_RING; return a registered fd index rather * than an fd. */ #define IORING_SETUP_REGISTERED_FD_ONLY (1U << 15) /* * Removes indirection through the SQ index array. */ #define IORING_SETUP_NO_SQARRAY (1U << 16) enum io_uring_op { IORING_OP_NOP, IORING_OP_READV, IORING_OP_WRITEV, IORING_OP_FSYNC, IORING_OP_READ_FIXED, IORING_OP_WRITE_FIXED, IORING_OP_POLL_ADD, IORING_OP_POLL_REMOVE, IORING_OP_SYNC_FILE_RANGE, IORING_OP_SENDMSG, IORING_OP_RECVMSG, IORING_OP_TIMEOUT, IORING_OP_TIMEOUT_REMOVE, IORING_OP_ACCEPT, IORING_OP_ASYNC_CANCEL, IORING_OP_LINK_TIMEOUT, IORING_OP_CONNECT, IORING_OP_FALLOCATE, IORING_OP_OPENAT, IORING_OP_CLOSE, IORING_OP_FILES_UPDATE, IORING_OP_STATX, IORING_OP_READ, IORING_OP_WRITE, IORING_OP_FADVISE, IORING_OP_MADVISE, IORING_OP_SEND, IORING_OP_RECV, IORING_OP_OPENAT2, IORING_OP_EPOLL_CTL, IORING_OP_SPLICE, IORING_OP_PROVIDE_BUFFERS, IORING_OP_REMOVE_BUFFERS, IORING_OP_TEE, IORING_OP_SHUTDOWN, IORING_OP_RENAMEAT, IORING_OP_UNLINKAT, IORING_OP_MKDIRAT, IORING_OP_SYMLINKAT, IORING_OP_LINKAT, IORING_OP_MSG_RING, IORING_OP_FSETXATTR, IORING_OP_SETXATTR, IORING_OP_FGETXATTR, IORING_OP_GETXATTR, IORING_OP_SOCKET, IORING_OP_URING_CMD, IORING_OP_SEND_ZC, IORING_OP_SENDMSG_ZC, IORING_OP_READ_MULTISHOT, IORING_OP_WAITID, IORING_OP_FUTEX_WAIT, IORING_OP_FUTEX_WAKE, IORING_OP_FUTEX_WAITV, IORING_OP_FIXED_FD_INSTALL, /* this goes last, obviously */ IORING_OP_LAST, }; /* * sqe->uring_cmd_flags top 8bits aren't available for userspace * IORING_URING_CMD_FIXED use registered buffer; pass this flag * along with setting sqe->buf_index. */ #define IORING_URING_CMD_FIXED (1U << 0) #define IORING_URING_CMD_MASK IORING_URING_CMD_FIXED /* * sqe->fsync_flags */ #define IORING_FSYNC_DATASYNC (1U << 0) /* * sqe->timeout_flags */ #define IORING_TIMEOUT_ABS (1U << 0) #define IORING_TIMEOUT_UPDATE (1U << 1) #define IORING_TIMEOUT_BOOTTIME (1U << 2) #define IORING_TIMEOUT_REALTIME (1U << 3) #define IORING_LINK_TIMEOUT_UPDATE (1U << 4) #define IORING_TIMEOUT_ETIME_SUCCESS (1U << 5) #define IORING_TIMEOUT_MULTISHOT (1U << 6) #define IORING_TIMEOUT_CLOCK_MASK (IORING_TIMEOUT_BOOTTIME | IORING_TIMEOUT_REALTIME) #define IORING_TIMEOUT_UPDATE_MASK (IORING_TIMEOUT_UPDATE | IORING_LINK_TIMEOUT_UPDATE) /* * sqe->splice_flags * extends splice(2) flags */ #define SPLICE_F_FD_IN_FIXED (1U << 31) /* the last bit of __u32 */ /* * POLL_ADD flags. Note that since sqe->poll_events is the flag space, the * command flags for POLL_ADD are stored in sqe->len. * * IORING_POLL_ADD_MULTI Multishot poll. Sets IORING_CQE_F_MORE if * the poll handler will continue to report * CQEs on behalf of the same SQE. * * IORING_POLL_UPDATE Update existing poll request, matching * sqe->addr as the old user_data field. * * IORING_POLL_LEVEL Level triggered poll. */ #define IORING_POLL_ADD_MULTI (1U << 0) #define IORING_POLL_UPDATE_EVENTS (1U << 1) #define IORING_POLL_UPDATE_USER_DATA (1U << 2) #define IORING_POLL_ADD_LEVEL (1U << 3) /* * ASYNC_CANCEL flags. * * IORING_ASYNC_CANCEL_ALL Cancel all requests that match the given key * IORING_ASYNC_CANCEL_FD Key off 'fd' for cancelation rather than the * request 'user_data' * IORING_ASYNC_CANCEL_ANY Match any request * IORING_ASYNC_CANCEL_FD_FIXED 'fd' passed in is a fixed descriptor * IORING_ASYNC_CANCEL_USERDATA Match on user_data, default for no other key * IORING_ASYNC_CANCEL_OP Match request based on opcode */ #define IORING_ASYNC_CANCEL_ALL (1U << 0) #define IORING_ASYNC_CANCEL_FD (1U << 1) #define IORING_ASYNC_CANCEL_ANY (1U << 2) #define IORING_ASYNC_CANCEL_FD_FIXED (1U << 3) #define IORING_ASYNC_CANCEL_USERDATA (1U << 4) #define IORING_ASYNC_CANCEL_OP (1U << 5) /* * send/sendmsg and recv/recvmsg flags (sqe->ioprio) * * IORING_RECVSEND_POLL_FIRST If set, instead of first attempting to send * or receive and arm poll if that yields an * -EAGAIN result, arm poll upfront and skip * the initial transfer attempt. * * IORING_RECV_MULTISHOT Multishot recv. Sets IORING_CQE_F_MORE if * the handler will continue to report * CQEs on behalf of the same SQE. * * IORING_RECVSEND_FIXED_BUF Use registered buffers, the index is stored in * the buf_index field. * * IORING_SEND_ZC_REPORT_USAGE * If set, SEND[MSG]_ZC should report * the zerocopy usage in cqe.res * for the IORING_CQE_F_NOTIF cqe. * 0 is reported if zerocopy was actually possible. * IORING_NOTIF_USAGE_ZC_COPIED if data was copied * (at least partially). */ #define IORING_RECVSEND_POLL_FIRST (1U << 0) #define IORING_RECV_MULTISHOT (1U << 1) #define IORING_RECVSEND_FIXED_BUF (1U << 2) #define IORING_SEND_ZC_REPORT_USAGE (1U << 3) /* * cqe.res for IORING_CQE_F_NOTIF if * IORING_SEND_ZC_REPORT_USAGE was requested * * It should be treated as a flag, all other * bits of cqe.res should be treated as reserved! */ #define IORING_NOTIF_USAGE_ZC_COPIED (1U << 31) /* * accept flags stored in sqe->ioprio */ #define IORING_ACCEPT_MULTISHOT (1U << 0) /* * IORING_OP_MSG_RING command types, stored in sqe->addr */ enum { IORING_MSG_DATA, /* pass sqe->len as 'res' and off as user_data */ IORING_MSG_SEND_FD, /* send a registered fd to another ring */ }; /* * IORING_OP_MSG_RING flags (sqe->msg_ring_flags) * * IORING_MSG_RING_CQE_SKIP Don't post a CQE to the target ring. Not * applicable for IORING_MSG_DATA, obviously. */ #define IORING_MSG_RING_CQE_SKIP (1U << 0) /* Pass through the flags from sqe->file_index to cqe->flags */ #define IORING_MSG_RING_FLAGS_PASS (1U << 1) /* * IORING_OP_FIXED_FD_INSTALL flags (sqe->install_fd_flags) * * IORING_FIXED_FD_NO_CLOEXEC Don't mark the fd as O_CLOEXEC */ #define IORING_FIXED_FD_NO_CLOEXEC (1U << 0) /* * IO completion data structure (Completion Queue Entry) */ struct io_uring_cqe { __u64 user_data; /* sqe->data submission passed back */ __s32 res; /* result code for this event */ __u32 flags; /* * If the ring is initialized with IORING_SETUP_CQE32, then this field * contains 16-bytes of padding, doubling the size of the CQE. */ __u64 big_cqe[]; }; /* * cqe->flags * * IORING_CQE_F_BUFFER If set, the upper 16 bits are the buffer ID * IORING_CQE_F_MORE If set, parent SQE will generate more CQE entries * IORING_CQE_F_SOCK_NONEMPTY If set, more data to read after socket recv * IORING_CQE_F_NOTIF Set for notification CQEs. Can be used to distinct * them from sends. */ #define IORING_CQE_F_BUFFER (1U << 0) #define IORING_CQE_F_MORE (1U << 1) #define IORING_CQE_F_SOCK_NONEMPTY (1U << 2) #define IORING_CQE_F_NOTIF (1U << 3) enum { IORING_CQE_BUFFER_SHIFT = 16, }; /* * Magic offsets for the application to mmap the data it needs */ #define IORING_OFF_SQ_RING 0ULL #define IORING_OFF_CQ_RING 0x8000000ULL #define IORING_OFF_SQES 0x10000000ULL #define IORING_OFF_PBUF_RING 0x80000000ULL #define IORING_OFF_PBUF_SHIFT 16 #define IORING_OFF_MMAP_MASK 0xf8000000ULL /* * Filled with the offset for mmap(2) */ struct io_sqring_offsets { __u32 head; __u32 tail; __u32 ring_mask; __u32 ring_entries; __u32 flags; __u32 dropped; __u32 array; __u32 resv1; __u64 user_addr; }; /* * sq_ring->flags */ #define IORING_SQ_NEED_WAKEUP (1U << 0) /* needs io_uring_enter wakeup */ #define IORING_SQ_CQ_OVERFLOW (1U << 1) /* CQ ring is overflown */ #define IORING_SQ_TASKRUN (1U << 2) /* task should enter the kernel */ struct io_cqring_offsets { __u32 head; __u32 tail; __u32 ring_mask; __u32 ring_entries; __u32 overflow; __u32 cqes; __u32 flags; __u32 resv1; __u64 user_addr; }; /* * cq_ring->flags */ /* disable eventfd notifications */ #define IORING_CQ_EVENTFD_DISABLED (1U << 0) /* * io_uring_enter(2) flags */ #define IORING_ENTER_GETEVENTS (1U << 0) #define IORING_ENTER_SQ_WAKEUP (1U << 1) #define IORING_ENTER_SQ_WAIT (1U << 2) #define IORING_ENTER_EXT_ARG (1U << 3) #define IORING_ENTER_REGISTERED_RING (1U << 4) /* * Passed in for io_uring_setup(2). Copied back with updated info on success */ struct io_uring_params { __u32 sq_entries; __u32 cq_entries; __u32 flags; __u32 sq_thread_cpu; __u32 sq_thread_idle; __u32 features; __u32 wq_fd; __u32 resv[3]; struct io_sqring_offsets sq_off; struct io_cqring_offsets cq_off; }; /* * io_uring_params->features flags */ #define IORING_FEAT_SINGLE_MMAP (1U << 0) #define IORING_FEAT_NODROP (1U << 1) #define IORING_FEAT_SUBMIT_STABLE (1U << 2) #define IORING_FEAT_RW_CUR_POS (1U << 3) #define IORING_FEAT_CUR_PERSONALITY (1U << 4) #define IORING_FEAT_FAST_POLL (1U << 5) #define IORING_FEAT_POLL_32BITS (1U << 6) #define IORING_FEAT_SQPOLL_NONFIXED (1U << 7) #define IORING_FEAT_EXT_ARG (1U << 8) #define IORING_FEAT_NATIVE_WORKERS (1U << 9) #define IORING_FEAT_RSRC_TAGS (1U << 10) #define IORING_FEAT_CQE_SKIP (1U << 11) #define IORING_FEAT_LINKED_FILE (1U << 12) #define IORING_FEAT_REG_REG_RING (1U << 13) /* * io_uring_register(2) opcodes and arguments */ enum { IORING_REGISTER_BUFFERS = 0, IORING_UNREGISTER_BUFFERS = 1, IORING_REGISTER_FILES = 2, IORING_UNREGISTER_FILES = 3, IORING_REGISTER_EVENTFD = 4, IORING_UNREGISTER_EVENTFD = 5, IORING_REGISTER_FILES_UPDATE = 6, IORING_REGISTER_EVENTFD_ASYNC = 7, IORING_REGISTER_PROBE = 8, IORING_REGISTER_PERSONALITY = 9, IORING_UNREGISTER_PERSONALITY = 10, IORING_REGISTER_RESTRICTIONS = 11, IORING_REGISTER_ENABLE_RINGS = 12, /* extended with tagging */ IORING_REGISTER_FILES2 = 13, IORING_REGISTER_FILES_UPDATE2 = 14, IORING_REGISTER_BUFFERS2 = 15, IORING_REGISTER_BUFFERS_UPDATE = 16, /* set/clear io-wq thread affinities */ IORING_REGISTER_IOWQ_AFF = 17, IORING_UNREGISTER_IOWQ_AFF = 18, /* set/get max number of io-wq workers */ IORING_REGISTER_IOWQ_MAX_WORKERS = 19, /* register/unregister io_uring fd with the ring */ IORING_REGISTER_RING_FDS = 20, IORING_UNREGISTER_RING_FDS = 21, /* register ring based provide buffer group */ IORING_REGISTER_PBUF_RING = 22, IORING_UNREGISTER_PBUF_RING = 23, /* sync cancelation API */ IORING_REGISTER_SYNC_CANCEL = 24, /* register a range of fixed file slots for automatic slot allocation */ IORING_REGISTER_FILE_ALLOC_RANGE = 25, /* return status information for a buffer group */ IORING_REGISTER_PBUF_STATUS = 26, /* this goes last */ IORING_REGISTER_LAST, /* flag added to the opcode to use a registered ring fd */ IORING_REGISTER_USE_REGISTERED_RING = 1U << 31 }; /* io-wq worker categories */ enum { IO_WQ_BOUND, IO_WQ_UNBOUND, }; /* deprecated, see struct io_uring_rsrc_update */ struct io_uring_files_update { __u32 offset; __u32 resv; __aligned_u64 /* __s32 * */ fds; }; /* * Register a fully sparse file space, rather than pass in an array of all * -1 file descriptors. */ #define IORING_RSRC_REGISTER_SPARSE (1U << 0) struct io_uring_rsrc_register { __u32 nr; __u32 flags; __u64 resv2; __aligned_u64 data; __aligned_u64 tags; }; struct io_uring_rsrc_update { __u32 offset; __u32 resv; __aligned_u64 data; }; struct io_uring_rsrc_update2 { __u32 offset; __u32 resv; __aligned_u64 data; __aligned_u64 tags; __u32 nr; __u32 resv2; }; /* Skip updating fd indexes set to this value in the fd table */ #define IORING_REGISTER_FILES_SKIP (-2) #define IO_URING_OP_SUPPORTED (1U << 0) struct io_uring_probe_op { __u8 op; __u8 resv; __u16 flags; /* IO_URING_OP_* flags */ __u32 resv2; }; struct io_uring_probe { __u8 last_op; /* last opcode supported */ __u8 ops_len; /* length of ops[] array below */ __u16 resv; __u32 resv2[3]; struct io_uring_probe_op ops[]; }; struct io_uring_restriction { __u16 opcode; union { __u8 register_op; /* IORING_RESTRICTION_REGISTER_OP */ __u8 sqe_op; /* IORING_RESTRICTION_SQE_OP */ __u8 sqe_flags; /* IORING_RESTRICTION_SQE_FLAGS_* */ }; __u8 resv; __u32 resv2[3]; }; struct io_uring_buf { __u64 addr; __u32 len; __u16 bid; __u16 resv; }; struct io_uring_buf_ring { union { /* * To avoid spilling into more pages than we need to, the * ring tail is overlaid with the io_uring_buf->resv field. */ struct { __u64 resv1; __u32 resv2; __u16 resv3; __u16 tail; }; __DECLARE_FLEX_ARRAY(struct io_uring_buf, bufs); }; }; /* * Flags for IORING_REGISTER_PBUF_RING. * * IOU_PBUF_RING_MMAP: If set, kernel will allocate the memory for the ring. * The application must not set a ring_addr in struct * io_uring_buf_reg, instead it must subsequently call * mmap(2) with the offset set as: * IORING_OFF_PBUF_RING | (bgid << IORING_OFF_PBUF_SHIFT) * to get a virtual mapping for the ring. */ enum { IOU_PBUF_RING_MMAP = 1, }; /* argument for IORING_(UN)REGISTER_PBUF_RING */ struct io_uring_buf_reg { __u64 ring_addr; __u32 ring_entries; __u16 bgid; __u16 flags; __u64 resv[3]; }; /* argument for IORING_REGISTER_PBUF_STATUS */ struct io_uring_buf_status { __u32 buf_group; /* input */ __u32 head; /* output */ __u32 resv[8]; }; /* * io_uring_restriction->opcode values */ enum { /* Allow an io_uring_register(2) opcode */ IORING_RESTRICTION_REGISTER_OP = 0, /* Allow an sqe opcode */ IORING_RESTRICTION_SQE_OP = 1, /* Allow sqe flags */ IORING_RESTRICTION_SQE_FLAGS_ALLOWED = 2, /* Require sqe flags (these flags must be set on each submission) */ IORING_RESTRICTION_SQE_FLAGS_REQUIRED = 3, IORING_RESTRICTION_LAST }; struct io_uring_getevents_arg { __u64 sigmask; __u32 sigmask_sz; __u32 pad; __u64 ts; }; /* * Argument for IORING_REGISTER_SYNC_CANCEL */ struct io_uring_sync_cancel_reg { __u64 addr; __s32 fd; __u32 flags; struct __kernel_timespec timeout; __u8 opcode; __u8 pad[7]; __u64 pad2[3]; }; /* * Argument for IORING_REGISTER_FILE_ALLOC_RANGE * The range is specified as [off, off + len) */ struct io_uring_file_index_range { __u32 off; __u32 len; __u64 resv; }; struct io_uring_recvmsg_out { __u32 namelen; __u32 controllen; __u32 payloadlen; __u32 flags; }; /* * Argument for IORING_OP_URING_CMD when file is a socket */ enum { SOCKET_URING_OP_SIOCINQ = 0, SOCKET_URING_OP_SIOCOUTQ, SOCKET_URING_OP_GETSOCKOPT, SOCKET_URING_OP_SETSOCKOPT, }; #ifdef __cplusplus } #endif #endif

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