linux/linux-5.18.11/fs/iomap/fiemap.c

125 lines
2.8 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2016-2021 Christoph Hellwig.
*/
#include <linux/module.h>
#include <linux/compiler.h>
#include <linux/fs.h>
#include <linux/iomap.h>
#include <linux/fiemap.h>
#include <linux/pagemap.h>
static int iomap_to_fiemap(struct fiemap_extent_info *fi,
const struct iomap *iomap, u32 flags)
{
switch (iomap->type) {
case IOMAP_HOLE:
/* skip holes */
return 0;
case IOMAP_DELALLOC:
flags |= FIEMAP_EXTENT_DELALLOC | FIEMAP_EXTENT_UNKNOWN;
break;
case IOMAP_MAPPED:
break;
case IOMAP_UNWRITTEN:
flags |= FIEMAP_EXTENT_UNWRITTEN;
break;
case IOMAP_INLINE:
flags |= FIEMAP_EXTENT_DATA_INLINE;
break;
}
if (iomap->flags & IOMAP_F_MERGED)
flags |= FIEMAP_EXTENT_MERGED;
if (iomap->flags & IOMAP_F_SHARED)
flags |= FIEMAP_EXTENT_SHARED;
return fiemap_fill_next_extent(fi, iomap->offset,
iomap->addr != IOMAP_NULL_ADDR ? iomap->addr : 0,
iomap->length, flags);
}
static loff_t iomap_fiemap_iter(const struct iomap_iter *iter,
struct fiemap_extent_info *fi, struct iomap *prev)
{
int ret;
if (iter->iomap.type == IOMAP_HOLE)
return iomap_length(iter);
ret = iomap_to_fiemap(fi, prev, 0);
*prev = iter->iomap;
switch (ret) {
case 0: /* success */
return iomap_length(iter);
case 1: /* extent array full */
return 0;
default: /* error */
return ret;
}
}
int iomap_fiemap(struct inode *inode, struct fiemap_extent_info *fi,
u64 start, u64 len, const struct iomap_ops *ops)
{
struct iomap_iter iter = {
.inode = inode,
.pos = start,
.len = len,
.flags = IOMAP_REPORT,
};
struct iomap prev = {
.type = IOMAP_HOLE,
};
int ret;
ret = fiemap_prep(inode, fi, start, &iter.len, 0);
if (ret)
return ret;
while ((ret = iomap_iter(&iter, ops)) > 0)
iter.processed = iomap_fiemap_iter(&iter, fi, &prev);
if (prev.type != IOMAP_HOLE) {
ret = iomap_to_fiemap(fi, &prev, FIEMAP_EXTENT_LAST);
if (ret < 0)
return ret;
}
/* inode with no (attribute) mapping will give ENOENT */
if (ret < 0 && ret != -ENOENT)
return ret;
return 0;
}
EXPORT_SYMBOL_GPL(iomap_fiemap);
/* legacy ->bmap interface. 0 is the error return (!) */
sector_t
iomap_bmap(struct address_space *mapping, sector_t bno,
const struct iomap_ops *ops)
{
struct iomap_iter iter = {
.inode = mapping->host,
.pos = (loff_t)bno << mapping->host->i_blkbits,
.len = i_blocksize(mapping->host),
.flags = IOMAP_REPORT,
};
const unsigned int blkshift = mapping->host->i_blkbits - SECTOR_SHIFT;
int ret;
if (filemap_write_and_wait(mapping))
return 0;
bno = 0;
while ((ret = iomap_iter(&iter, ops)) > 0) {
if (iter.iomap.type == IOMAP_MAPPED)
bno = iomap_sector(&iter.iomap, iter.pos) >> blkshift;
/* leave iter.processed unset to abort loop */
}
if (ret)
return 0;
return bno;
}
EXPORT_SYMBOL_GPL(iomap_bmap);