Function report

Linux Kernel

v5.5.9

Brick Technologies Co., Ltd

Source Code:fs\io_uring.c Create Date:2022-07-28 20:22:11
Last Modify:2020-03-12 14:18:49 Copyright©Brick
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Name:For files that don't have ->read_iter() and ->write_iter(), handle them* by looping over ->read() or ->write() manually.

Proto:static ssize_t loop_rw_iter(int rw, struct file *file, struct kiocb *kiocb, struct iov_iter *iter)

Type:ssize_t

Parameter:

TypeParameterName
intrw
struct file *file
struct kiocb *kiocb
struct iov_iter *iter
1709  ret = 0
1716  If ki_flags & IOCB_HIPRI Then Return -EOPNOTSUPP
1718  If ki_flags & IOCB_NOWAIT Then Return -EAGAIN
1721  When iov_iter_count(iter) cycle
1725  If Not iov_iter_is_bvec(iter) Then
1726  iovec = iov_iter_iovec(iter)
1727  Else
1729  BSD uses caddr_t (1003.1g requires void *) = kmap(bv_page) + iov_offset
1731  Must be size_t (1003.1g) = min - return minimum of two values of the same or compatible types*@x: first value*@y: second value(count, bv_len - iov_offset)
1735  If rw == generic data direction definitions Then
1736  nr = read(file, BSD uses caddr_t (1003.1g requires void *) , Must be size_t (1003.1g) , & The 'ki_filp' pointer is shared in a union for aio )
1738  Else
1739  nr = write(file, BSD uses caddr_t (1003.1g requires void *) , Must be size_t (1003.1g) , & The 'ki_filp' pointer is shared in a union for aio )
1743  If iov_iter_is_bvec(iter) Then kunmap(bv_page)
1746  If nr < 0 Then
1747  If Not ret Then ret = nr
1749  Break
1751  ret += nr
1752  If nr != Must be size_t (1003.1g) Then Break
1754  iov_iter_advance(iter, nr)
1757  Return ret
Caller
NameDescribe
io_read
io_write