mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-11-11 04:18:39 +08:00
c4740bf1ed
Rewrite iomap_seek_data to use iomap_iter. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
105 lines
2.3 KiB
C
105 lines
2.3 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
|
|
* Copyright (C) 2017 Red Hat, Inc.
|
|
* Copyright (c) 2018-2021 Christoph Hellwig.
|
|
*/
|
|
#include <linux/module.h>
|
|
#include <linux/compiler.h>
|
|
#include <linux/fs.h>
|
|
#include <linux/iomap.h>
|
|
#include <linux/pagemap.h>
|
|
#include <linux/pagevec.h>
|
|
|
|
static loff_t iomap_seek_hole_iter(const struct iomap_iter *iter,
|
|
loff_t *hole_pos)
|
|
{
|
|
loff_t length = iomap_length(iter);
|
|
|
|
switch (iter->iomap.type) {
|
|
case IOMAP_UNWRITTEN:
|
|
*hole_pos = mapping_seek_hole_data(iter->inode->i_mapping,
|
|
iter->pos, iter->pos + length, SEEK_HOLE);
|
|
if (*hole_pos == iter->pos + length)
|
|
return length;
|
|
return 0;
|
|
case IOMAP_HOLE:
|
|
*hole_pos = iter->pos;
|
|
return 0;
|
|
default:
|
|
return length;
|
|
}
|
|
}
|
|
|
|
loff_t
|
|
iomap_seek_hole(struct inode *inode, loff_t pos, const struct iomap_ops *ops)
|
|
{
|
|
loff_t size = i_size_read(inode);
|
|
struct iomap_iter iter = {
|
|
.inode = inode,
|
|
.pos = pos,
|
|
.flags = IOMAP_REPORT,
|
|
};
|
|
int ret;
|
|
|
|
/* Nothing to be found before or beyond the end of the file. */
|
|
if (pos < 0 || pos >= size)
|
|
return -ENXIO;
|
|
|
|
iter.len = size - pos;
|
|
while ((ret = iomap_iter(&iter, ops)) > 0)
|
|
iter.processed = iomap_seek_hole_iter(&iter, &pos);
|
|
if (ret < 0)
|
|
return ret;
|
|
if (iter.len) /* found hole before EOF */
|
|
return pos;
|
|
return size;
|
|
}
|
|
EXPORT_SYMBOL_GPL(iomap_seek_hole);
|
|
|
|
static loff_t iomap_seek_data_iter(const struct iomap_iter *iter,
|
|
loff_t *hole_pos)
|
|
{
|
|
loff_t length = iomap_length(iter);
|
|
|
|
switch (iter->iomap.type) {
|
|
case IOMAP_HOLE:
|
|
return length;
|
|
case IOMAP_UNWRITTEN:
|
|
*hole_pos = mapping_seek_hole_data(iter->inode->i_mapping,
|
|
iter->pos, iter->pos + length, SEEK_DATA);
|
|
if (*hole_pos < 0)
|
|
return length;
|
|
return 0;
|
|
default:
|
|
*hole_pos = iter->pos;
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
loff_t
|
|
iomap_seek_data(struct inode *inode, loff_t pos, const struct iomap_ops *ops)
|
|
{
|
|
loff_t size = i_size_read(inode);
|
|
struct iomap_iter iter = {
|
|
.inode = inode,
|
|
.pos = pos,
|
|
.flags = IOMAP_REPORT,
|
|
};
|
|
int ret;
|
|
|
|
/* Nothing to be found before or beyond the end of the file. */
|
|
if (pos < 0 || pos >= size)
|
|
return -ENXIO;
|
|
|
|
iter.len = size - pos;
|
|
while ((ret = iomap_iter(&iter, ops)) > 0)
|
|
iter.processed = iomap_seek_data_iter(&iter, &pos);
|
|
if (ret < 0)
|
|
return ret;
|
|
if (iter.len) /* found data before EOF */
|
|
return pos;
|
|
/* We've reached the end of the file without finding data */
|
|
return -ENXIO;
|
|
}
|
|
EXPORT_SYMBOL_GPL(iomap_seek_data);
|