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diff --git a/man2/io_submit.2 b/man2/io_submit.2 deleted file mode 100644 index c53ae9aaf..000000000 --- a/man2/io_submit.2 +++ /dev/null @@ -1,289 +0,0 @@ -.\" Copyright (C) 2003 Free Software Foundation, Inc. -.\" and Copyright (C) 2017 Goldwyn Rodrigues <rgoldwyn@suse.de> -.\" -.\" SPDX-License-Identifier: GPL-1.0-or-later -.\" -.TH io_submit 2 (date) "Linux man-pages (unreleased)" -.SH NAME -io_submit \- submit asynchronous I/O blocks for processing -.SH LIBRARY -Standard C library -.RI ( libc ", " \-lc ) -.P -Alternatively, Asynchronous I/O library -.RI ( libaio ", " \-laio ); -see VERSIONS. -.SH SYNOPSIS -.nf -.BR "#include <linux/aio_abi.h>" " /* Defines needed types */" -.P -.BI "int io_submit(aio_context_t " ctx_id ", long " nr \ -", struct iocb **" iocbpp ); -.fi -.P -.IR Note : -There is no glibc wrapper for this system call; see VERSIONS. -.SH DESCRIPTION -.IR Note : -this page describes the raw Linux system call interface. -The wrapper function provided by -.I libaio -uses a different type for the -.I ctx_id -argument. -See VERSIONS. -.P -The -.BR io_submit () -system call -queues \fInr\fP I/O request blocks for processing in -the AIO context \fIctx_id\fP. -The -.I iocbpp -argument should be an array of \fInr\fP AIO control blocks, -which will be submitted to context \fIctx_id\fP. -.P -The -.I iocb -(I/O control block) structure defined in -.I linux/aio_abi.h -defines the parameters that control the I/O operation. -.P -.in +4n -.EX -#include <linux/aio_abi.h> -\& -struct iocb { - __u64 aio_data; - __u32 PADDED(aio_key, aio_rw_flags); - __u16 aio_lio_opcode; - __s16 aio_reqprio; - __u32 aio_fildes; - __u64 aio_buf; - __u64 aio_nbytes; - __s64 aio_offset; - __u64 aio_reserved2; - __u32 aio_flags; - __u32 aio_resfd; -}; -.EE -.in -.P -The fields of this structure are as follows: -.TP -.I aio_data -This data is copied into the -.I data -field of the -.I io_event -structure upon I/O completion (see -.BR io_getevents (2)). -.TP -.I aio_key -This is an internal field used by the kernel. -Do not modify this field after an -.BR io_submit () -call. -.TP -.I aio_rw_flags -This defines the R/W flags passed with structure. -The valid values are: -.RS -.TP -.BR RWF_APPEND " (since Linux 4.16)" -.\" commit e1fc742e14e01d84d9693c4aca4ab23da65811fb -Append data to the end of the file. -See the description of the flag of the same name in -.BR pwritev2 (2) -as well as the description of -.B O_APPEND -in -.BR open (2). -The -.I aio_offset -field is ignored. -The file offset is not changed. -.TP -.BR RWF_DSYNC " (since Linux 4.13)" -Write operation complete according to requirement of -synchronized I/O data integrity. -See the description of the flag of the same name in -.BR pwritev2 (2) -as well the description of -.B O_DSYNC -in -.BR open (2). -.TP -.BR RWF_HIPRI " (since Linux 4.13)" -High priority request, poll if possible -.TP -.BR RWF_NOWAIT " (since Linux 4.14)" -Don't wait if the I/O will block for operations such as -file block allocations, dirty page flush, mutex locks, -or a congested block device inside the kernel. -If any of these conditions are met, the control block is returned -immediately with a return value of -.B \-EAGAIN -in the -.I res -field of the -.I io_event -structure (see -.BR io_getevents (2)). -.TP -.BR RWF_SYNC " (since Linux 4.13)" -Write operation complete according to requirement of -synchronized I/O file integrity. -See the description of the flag of the same name in -.BR pwritev2 (2) -as well the description of -.B O_SYNC -in -.BR open (2). -.RE -.TP -.I aio_lio_opcode -This defines the type of I/O to be performed by the -.I iocb -structure. -The -valid values are defined by the enum defined in -.IR linux/aio_abi.h : -.IP -.in +4n -.EX -enum { - IOCB_CMD_PREAD = 0, - IOCB_CMD_PWRITE = 1, - IOCB_CMD_FSYNC = 2, - IOCB_CMD_FDSYNC = 3, - IOCB_CMD_POLL = 5, - IOCB_CMD_NOOP = 6, - IOCB_CMD_PREADV = 7, - IOCB_CMD_PWRITEV = 8, -}; -.EE -.in -.TP -.I aio_reqprio -This defines the requests priority. -.TP -.I aio_fildes -The file descriptor on which the I/O operation is to be performed. -.TP -.I aio_buf -This is the buffer used to transfer data for a read or write operation. -.TP -.I aio_nbytes -This is the size of the buffer pointed to by -.IR aio_buf . -.TP -.I aio_offset -This is the file offset at which the I/O operation is to be performed. -.TP -.I aio_flags -This is the set of flags associated with the -.I iocb -structure. -The valid values are: -.RS -.TP -.B IOCB_FLAG_RESFD -Asynchronous I/O control must signal the file -descriptor mentioned in -.I aio_resfd -upon completion. -.TP -.BR IOCB_FLAG_IOPRIO " (since Linux 4.18)" -.\" commit d9a08a9e616beeccdbd0e7262b7225ffdfa49e92 -Interpret the -.I aio_reqprio -field as an -.B IOPRIO_VALUE -as defined by -.IR linux/ioprio.h . -.RE -.TP -.I aio_resfd -The file descriptor to signal in the event of asynchronous I/O completion. -.SH RETURN VALUE -On success, -.BR io_submit () -returns the number of \fIiocb\fPs submitted (which may be -less than \fInr\fP, or 0 if \fInr\fP is zero). -For the failure return, see VERSIONS. -.SH ERRORS -.TP -.B EAGAIN -Insufficient resources are available to queue any \fIiocb\fPs. -.TP -.B EBADF -The file descriptor specified in the first \fIiocb\fP is invalid. -.TP -.B EFAULT -One of the data structures points to invalid data. -.TP -.B EINVAL -The AIO context specified by \fIctx_id\fP is invalid. -\fInr\fP is less than 0. -The \fIiocb\fP at -.I *iocbpp[0] -is not properly initialized, the operation specified is invalid for the file -descriptor in the \fIiocb\fP, or the value in the -.I aio_reqprio -field is invalid. -.TP -.B ENOSYS -.BR io_submit () -is not implemented on this architecture. -.TP -.B EPERM -The -.I aio_reqprio -field is set with the class -.BR IOPRIO_CLASS_RT , -but the submitting context does not have the -.B CAP_SYS_ADMIN -capability. -.SH VERSIONS -glibc does not provide a wrapper for this system call. -You could invoke it using -.BR syscall (2). -But instead, you probably want to use the -.BR io_submit () -wrapper function provided by -.\" http://git.fedorahosted.org/git/?p=libaio.git -.IR libaio . -.P -Note that the -.I libaio -wrapper function uses a different type -.RI ( io_context_t ) -.\" But glibc is confused, since <libaio.h> uses 'io_context_t' to declare -.\" the system call. -for the -.I ctx_id -argument. -Note also that the -.I libaio -wrapper does not follow the usual C library conventions for indicating errors: -on error it returns a negated error number -(the negative of one of the values listed in ERRORS). -If the system call is invoked via -.BR syscall (2), -then the return value follows the usual conventions for -indicating an error: \-1, with -.I errno -set to a (positive) value that indicates the error. -.SH STANDARDS -Linux. -.SH HISTORY -Linux 2.5. -.SH SEE ALSO -.BR io_cancel (2), -.BR io_destroy (2), -.BR io_getevents (2), -.BR io_setup (2), -.BR aio (7) -.\" .SH AUTHOR -.\" Kent Yoder. |