filemap: add a kiocb_write_and_wait helper

Factor out a helper that does filemap_write_and_wait_range for the range
covered by a read kiocb, or returns -EAGAIN if the kiocb is marked as
nowait and there would be pages to write.

Link: https://lkml.kernel.org/r/20230601145904.1385409-5-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Acked-by: Darrick J. Wong <djwong@kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andreas Gruenbacher <agruenba@redhat.com>
Cc: Anna Schumaker <anna@kernel.org>
Cc: Chao Yu <chao@kernel.org>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Ilya Dryomov <idryomov@gmail.com>
Cc: Jaegeuk Kim <jaegeuk@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Miklos Szeredi <mszeredi@redhat.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Christoph Hellwig 2023-06-01 16:58:56 +02:00 committed by Andrew Morton
parent 182c25e9c1
commit 3c435a0fe3
3 changed files with 23 additions and 27 deletions

View File

@ -576,21 +576,9 @@ static ssize_t blkdev_read_iter(struct kiocb *iocb, struct iov_iter *to)
goto reexpand; /* skip atime */
if (iocb->ki_flags & IOCB_DIRECT) {
struct address_space *mapping = iocb->ki_filp->f_mapping;
if (iocb->ki_flags & IOCB_NOWAIT) {
if (filemap_range_needs_writeback(mapping, pos,
pos + count - 1)) {
ret = -EAGAIN;
goto reexpand;
}
} else {
ret = filemap_write_and_wait_range(mapping, pos,
pos + count - 1);
if (ret < 0)
goto reexpand;
}
ret = kiocb_write_and_wait(iocb, count);
if (ret < 0)
goto reexpand;
file_accessed(iocb->ki_filp);
ret = blkdev_direct_IO(iocb, to);

View File

@ -30,6 +30,7 @@ static inline void invalidate_remote_inode(struct inode *inode)
int invalidate_inode_pages2(struct address_space *mapping);
int invalidate_inode_pages2_range(struct address_space *mapping,
pgoff_t start, pgoff_t end);
int write_inode_now(struct inode *, int sync);
int filemap_fdatawrite(struct address_space *);
int filemap_flush(struct address_space *);
@ -54,6 +55,7 @@ int filemap_check_errors(struct address_space *mapping);
void __filemap_set_wb_err(struct address_space *mapping, int err);
int filemap_fdatawrite_wbc(struct address_space *mapping,
struct writeback_control *wbc);
int kiocb_write_and_wait(struct kiocb *iocb, size_t count);
static inline int filemap_write_and_wait(struct address_space *mapping)
{

View File

@ -2735,6 +2735,21 @@ put_folios:
}
EXPORT_SYMBOL_GPL(filemap_read);
int kiocb_write_and_wait(struct kiocb *iocb, size_t count)
{
struct address_space *mapping = iocb->ki_filp->f_mapping;
loff_t pos = iocb->ki_pos;
loff_t end = pos + count - 1;
if (iocb->ki_flags & IOCB_NOWAIT) {
if (filemap_range_needs_writeback(mapping, pos, end))
return -EAGAIN;
return 0;
}
return filemap_write_and_wait_range(mapping, pos, end);
}
/**
* generic_file_read_iter - generic filesystem read routine
* @iocb: kernel I/O control block
@ -2770,18 +2785,9 @@ generic_file_read_iter(struct kiocb *iocb, struct iov_iter *iter)
struct address_space *mapping = file->f_mapping;
struct inode *inode = mapping->host;
if (iocb->ki_flags & IOCB_NOWAIT) {
if (filemap_range_needs_writeback(mapping, iocb->ki_pos,
iocb->ki_pos + count - 1))
return -EAGAIN;
} else {
retval = filemap_write_and_wait_range(mapping,
iocb->ki_pos,
iocb->ki_pos + count - 1);
if (retval < 0)
return retval;
}
retval = kiocb_write_and_wait(iocb, count);
if (retval < 0)
return retval;
file_accessed(file);
retval = mapping->a_ops->direct_IO(iocb, iter);