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These functions are page cache functionality and don't need to be declared in fs.h. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
125 lines
2.8 KiB
C
125 lines
2.8 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* Copyright (c) 2016-2021 Christoph Hellwig.
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*/
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#include <linux/module.h>
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#include <linux/compiler.h>
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#include <linux/fs.h>
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#include <linux/iomap.h>
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#include <linux/fiemap.h>
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#include <linux/pagemap.h>
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static int iomap_to_fiemap(struct fiemap_extent_info *fi,
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const struct iomap *iomap, u32 flags)
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{
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switch (iomap->type) {
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case IOMAP_HOLE:
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/* skip holes */
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return 0;
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case IOMAP_DELALLOC:
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flags |= FIEMAP_EXTENT_DELALLOC | FIEMAP_EXTENT_UNKNOWN;
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break;
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case IOMAP_MAPPED:
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break;
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case IOMAP_UNWRITTEN:
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flags |= FIEMAP_EXTENT_UNWRITTEN;
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break;
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case IOMAP_INLINE:
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flags |= FIEMAP_EXTENT_DATA_INLINE;
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break;
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}
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if (iomap->flags & IOMAP_F_MERGED)
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flags |= FIEMAP_EXTENT_MERGED;
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if (iomap->flags & IOMAP_F_SHARED)
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flags |= FIEMAP_EXTENT_SHARED;
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return fiemap_fill_next_extent(fi, iomap->offset,
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iomap->addr != IOMAP_NULL_ADDR ? iomap->addr : 0,
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iomap->length, flags);
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}
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static loff_t iomap_fiemap_iter(const struct iomap_iter *iter,
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struct fiemap_extent_info *fi, struct iomap *prev)
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{
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int ret;
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if (iter->iomap.type == IOMAP_HOLE)
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return iomap_length(iter);
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ret = iomap_to_fiemap(fi, prev, 0);
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*prev = iter->iomap;
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switch (ret) {
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case 0: /* success */
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return iomap_length(iter);
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case 1: /* extent array full */
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return 0;
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default: /* error */
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return ret;
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}
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}
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int iomap_fiemap(struct inode *inode, struct fiemap_extent_info *fi,
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u64 start, u64 len, const struct iomap_ops *ops)
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{
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struct iomap_iter iter = {
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.inode = inode,
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.pos = start,
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.len = len,
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.flags = IOMAP_REPORT,
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};
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struct iomap prev = {
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.type = IOMAP_HOLE,
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};
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int ret;
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ret = fiemap_prep(inode, fi, start, &iter.len, 0);
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if (ret)
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return ret;
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while ((ret = iomap_iter(&iter, ops)) > 0)
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iter.processed = iomap_fiemap_iter(&iter, fi, &prev);
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if (prev.type != IOMAP_HOLE) {
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ret = iomap_to_fiemap(fi, &prev, FIEMAP_EXTENT_LAST);
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if (ret < 0)
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return ret;
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}
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/* inode with no (attribute) mapping will give ENOENT */
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if (ret < 0 && ret != -ENOENT)
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return ret;
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return 0;
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}
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EXPORT_SYMBOL_GPL(iomap_fiemap);
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/* legacy ->bmap interface. 0 is the error return (!) */
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sector_t
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iomap_bmap(struct address_space *mapping, sector_t bno,
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const struct iomap_ops *ops)
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{
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struct iomap_iter iter = {
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.inode = mapping->host,
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.pos = (loff_t)bno << mapping->host->i_blkbits,
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.len = i_blocksize(mapping->host),
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.flags = IOMAP_REPORT,
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};
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const unsigned int blkshift = mapping->host->i_blkbits - SECTOR_SHIFT;
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int ret;
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if (filemap_write_and_wait(mapping))
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return 0;
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bno = 0;
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while ((ret = iomap_iter(&iter, ops)) > 0) {
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if (iter.iomap.type == IOMAP_MAPPED)
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bno = iomap_sector(&iter.iomap, iter.pos) >> blkshift;
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/* leave iter.processed unset to abort loop */
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}
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if (ret)
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return 0;
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return bno;
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}
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EXPORT_SYMBOL_GPL(iomap_bmap);
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