iomap: remove iomap_apply

iomap_apply is unused now, so remove it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
[djwong: rebase this patch to preserve git history of iomap loop control]
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>

diff --git a/fs/iomap/apply.c b/fs/iomap/apply.c
index e82647a..a1c7592 100644 (file)
--- a/fs/iomap/apply.c
+++ b/fs/iomap/apply.c
@@ -3,101 +3,10 @@
  * Copyright (C) 2010 Red Hat, Inc.
  * Copyright (c) 2016-2021 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)) {
-               written = -EIO;
-               goto out;
-       }
-       if (WARN_ON(iomap.length == 0)) {
-               written = -EIO;
-               goto out;
-       }
-
-       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);
-
-out:
-       /*
-        * 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;
-}
-
 static inline int iomap_iter_advance(struct iomap_iter *iter)
 {
        /* handle the previous iteration (if any) */

diff --git a/fs/iomap/trace.h b/fs/iomap/trace.h
index 1012d7a..f1519f9 100644 (file)
--- a/fs/iomap/trace.h
+++ b/fs/iomap/trace.h
@@ -138,49 +138,9 @@ DECLARE_EVENT_CLASS(iomap_class,
 DEFINE_EVENT(iomap_class, name,        \
        TP_PROTO(struct inode *inode, struct iomap *iomap), \
        TP_ARGS(inode, iomap))
-DEFINE_IOMAP_EVENT(iomap_apply_dstmap);
-DEFINE_IOMAP_EVENT(iomap_apply_srcmap);
 DEFINE_IOMAP_EVENT(iomap_iter_dstmap);
 DEFINE_IOMAP_EVENT(iomap_iter_srcmap);
 
-TRACE_EVENT(iomap_apply,
-       TP_PROTO(struct inode *inode, loff_t pos, loff_t length,
-               unsigned int flags, const void *ops, void *actor,
-               unsigned long caller),
-       TP_ARGS(inode, pos, length, flags, ops, actor, caller),
-       TP_STRUCT__entry(
-               __field(dev_t, dev)
-               __field(u64, ino)
-               __field(loff_t, pos)
-               __field(loff_t, length)
-               __field(unsigned int, flags)
-               __field(const void *, ops)
-               __field(void *, actor)
-               __field(unsigned long, caller)
-       ),
-       TP_fast_assign(
-               __entry->dev = inode->i_sb->s_dev;
-               __entry->ino = inode->i_ino;
-               __entry->pos = pos;
-               __entry->length = length;
-               __entry->flags = flags;
-               __entry->ops = ops;
-               __entry->actor = actor;
-               __entry->caller = caller;
-       ),
-       TP_printk("dev %d:%d ino 0x%llx pos %lld length %lld flags %s (0x%x) "
-                 "ops %ps caller %pS actor %ps",
-                 MAJOR(__entry->dev), MINOR(__entry->dev),
-                  __entry->ino,
-                  __entry->pos,
-                  __entry->length,
-                  __print_flags(__entry->flags, "|", IOMAP_FLAGS_STRINGS),
-                  __entry->flags,
-                  __entry->ops,
-                  (void *)__entry->caller,
-                  __entry->actor)
-);
-
 TRACE_EVENT(iomap_iter,
        TP_PROTO(struct iomap_iter *iter, const void *ops,
                 unsigned long caller),

diff --git a/include/linux/iomap.h b/include/linux/iomap.h
index 66e04ae..6784a8b 100644 (file)
--- a/include/linux/iomap.h
+++ b/include/linux/iomap.h
@@ -217,16 +217,6 @@ static inline struct iomap *iomap_iter_srcmap(struct iomap_iter *i)
        return &i->iomap;
 }
 
-/*
- * Main iomap iterator function.
- */
-typedef loff_t (*iomap_actor_t)(struct inode *inode, loff_t pos, loff_t len,
-               void *data, struct iomap *iomap, struct iomap *srcmap);
-
-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);
-
 ssize_t iomap_file_buffered_write(struct kiocb *iocb, struct iov_iter *from,
                const struct iomap_ops *ops);
 int iomap_readpage(struct page *page, const struct iomap_ops *ops);