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-rw-r--r--fs/iomap/apply.c94
1 files changed, 0 insertions, 94 deletions
diff --git a/fs/iomap/apply.c b/fs/iomap/apply.c
deleted file mode 100644
index 76925b40b5fd..000000000000
--- a/fs/iomap/apply.c
+++ /dev/null
@@ -1,94 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * Copyright (C) 2010 Red Hat, Inc.
- * Copyright (c) 2016-2018 Christoph Hellwig.
- */
-#include <linux/module.h>
-#include <linux/compiler.h>
-#include <linux/fs.h>
-#include <linux/iomap.h>
-#include "trace.h"
-
-/*
- * Execute a iomap write on a segment of the mapping that spans a
- * contiguous range of pages that have identical block mapping state.
- *
- * This avoids the need to map pages individually, do individual allocations
- * for each page and most importantly avoid the need for filesystem specific
- * locking per page. Instead, all the operations are amortised over the entire
- * range of pages. It is assumed that the filesystems will lock whatever
- * resources they require in the iomap_begin call, and release them in the
- * iomap_end call.
- */
-loff_t
-iomap_apply(struct inode *inode, loff_t pos, loff_t length, unsigned flags,
- const struct iomap_ops *ops, void *data, iomap_actor_t actor)
-{
- struct iomap iomap = { .type = IOMAP_HOLE };
- struct iomap srcmap = { .type = IOMAP_HOLE };
- loff_t written = 0, ret;
- u64 end;
-
- trace_iomap_apply(inode, pos, length, flags, ops, actor, _RET_IP_);
-
- /*
- * Need to map a range from start position for length bytes. This can
- * span multiple pages - it is only guaranteed to return a range of a
- * single type of pages (e.g. all into a hole, all mapped or all
- * unwritten). Failure at this point has nothing to undo.
- *
- * If allocation is required for this range, reserve the space now so
- * that the allocation is guaranteed to succeed later on. Once we copy
- * the data into the page cache pages, then we cannot fail otherwise we
- * expose transient stale data. If the reserve fails, we can safely
- * back out at this point as there is nothing to undo.
- */
- ret = ops->iomap_begin(inode, pos, length, flags, &iomap, &srcmap);
- if (ret)
- return ret;
- if (WARN_ON(iomap.offset > pos))
- return -EIO;
- if (WARN_ON(iomap.length == 0))
- return -EIO;
-
- trace_iomap_apply_dstmap(inode, &iomap);
- if (srcmap.type != IOMAP_HOLE)
- trace_iomap_apply_srcmap(inode, &srcmap);
-
- /*
- * Cut down the length to the one actually provided by the filesystem,
- * as it might not be able to give us the whole size that we requested.
- */
- end = iomap.offset + iomap.length;
- if (srcmap.type != IOMAP_HOLE)
- end = min(end, srcmap.offset + srcmap.length);
- if (pos + length > end)
- length = end - pos;
-
- /*
- * Now that we have guaranteed that the space allocation will succeed,
- * we can do the copy-in page by page without having to worry about
- * failures exposing transient data.
- *
- * To support COW operations, we read in data for partially blocks from
- * the srcmap if the file system filled it in. In that case we the
- * length needs to be limited to the earlier of the ends of the iomaps.
- * If the file system did not provide a srcmap we pass in the normal
- * iomap into the actors so that they don't need to have special
- * handling for the two cases.
- */
- written = actor(inode, pos, length, data, &iomap,
- srcmap.type != IOMAP_HOLE ? &srcmap : &iomap);
-
- /*
- * Now the data has been copied, commit the range we've copied. This
- * should not fail unless the filesystem has had a fatal error.
- */
- if (ops->iomap_end) {
- ret = ops->iomap_end(inode, pos, length,
- written > 0 ? written : 0,
- flags, &iomap);
- }
-
- return written ? written : ret;
-}