Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 134 insertions, 0 deletions

diff --git a/fs/ntfs/index.h b/fs/ntfs/index.h
new file mode 100644
index 0000000000..bb3c3ae551
--- /dev/null
+++ b/fs/ntfs/index.h
@@ -0,0 +1,134 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * index.h - Defines for NTFS kernel index handling.  Part of the Linux-NTFS
+ *	     project.
+ *
+ * Copyright (c) 2004 Anton Altaparmakov
+ */
+
+#ifndef _LINUX_NTFS_INDEX_H
+#define _LINUX_NTFS_INDEX_H
+
+#include <linux/fs.h>
+
+#include "types.h"
+#include "layout.h"
+#include "inode.h"
+#include "attrib.h"
+#include "mft.h"
+#include "aops.h"
+
+/**
+ * @idx_ni:	index inode containing the @entry described by this context
+ * @entry:	index entry (points into @ir or @ia)
+ * @data:	index entry data (points into @entry)
+ * @data_len:	length in bytes of @data
+ * @is_in_root:	'true' if @entry is in @ir and 'false' if it is in @ia
+ * @ir:		index root if @is_in_root and NULL otherwise
+ * @actx:	attribute search context if @is_in_root and NULL otherwise
+ * @base_ni:	base inode if @is_in_root and NULL otherwise
+ * @ia:		index block if @is_in_root is 'false' and NULL otherwise
+ * @page:	page if @is_in_root is 'false' and NULL otherwise
+ *
+ * @idx_ni is the index inode this context belongs to.
+ *
+ * @entry is the index entry described by this context.  @data and @data_len
+ * are the index entry data and its length in bytes, respectively.  @data
+ * simply points into @entry.  This is probably what the user is interested in.
+ *
+ * If @is_in_root is 'true', @entry is in the index root attribute @ir described
+ * by the attribute search context @actx and the base inode @base_ni.  @ia and
+ * @page are NULL in this case.
+ *
+ * If @is_in_root is 'false', @entry is in the index allocation attribute and @ia
+ * and @page point to the index allocation block and the mapped, locked page it
+ * is in, respectively.  @ir, @actx and @base_ni are NULL in this case.
+ *
+ * To obtain a context call ntfs_index_ctx_get().
+ *
+ * We use this context to allow ntfs_index_lookup() to return the found index
+ * @entry and its @data without having to allocate a buffer and copy the @entry
+ * and/or its @data into it.
+ *
+ * When finished with the @entry and its @data, call ntfs_index_ctx_put() to
+ * free the context and other associated resources.
+ *
+ * If the index entry was modified, call flush_dcache_index_entry_page()
+ * immediately after the modification and either ntfs_index_entry_mark_dirty()
+ * or ntfs_index_entry_write() before the call to ntfs_index_ctx_put() to
+ * ensure that the changes are written to disk.
+ */
+typedef struct {
+	ntfs_inode *idx_ni;
+	INDEX_ENTRY *entry;
+	void *data;
+	u16 data_len;
+	bool is_in_root;
+	INDEX_ROOT *ir;
+	ntfs_attr_search_ctx *actx;
+	ntfs_inode *base_ni;
+	INDEX_ALLOCATION *ia;
+	struct page *page;
+} ntfs_index_context;
+
+extern ntfs_index_context *ntfs_index_ctx_get(ntfs_inode *idx_ni);
+extern void ntfs_index_ctx_put(ntfs_index_context *ictx);
+
+extern int ntfs_index_lookup(const void *key, const int key_len,
+		ntfs_index_context *ictx);
+
+#ifdef NTFS_RW
+
+/**
+ * ntfs_index_entry_flush_dcache_page - flush_dcache_page() for index entries
+ * @ictx:	ntfs index context describing the index entry
+ *
+ * Call flush_dcache_page() for the page in which an index entry resides.
+ *
+ * This must be called every time an index entry is modified, just after the
+ * modification.
+ *
+ * If the index entry is in the index root attribute, simply flush the page
+ * containing the mft record containing the index root attribute.
+ *
+ * If the index entry is in an index block belonging to the index allocation
+ * attribute, simply flush the page cache page containing the index block.
+ */
+static inline void ntfs_index_entry_flush_dcache_page(ntfs_index_context *ictx)
+{
+	if (ictx->is_in_root)
+		flush_dcache_mft_record_page(ictx->actx->ntfs_ino);
+	else
+		flush_dcache_page(ictx->page);
+}
+
+/**
+ * ntfs_index_entry_mark_dirty - mark an index entry dirty
+ * @ictx:	ntfs index context describing the index entry
+ *
+ * Mark the index entry described by the index entry context @ictx dirty.
+ *
+ * If the index entry is in the index root attribute, simply mark the mft
+ * record containing the index root attribute dirty.  This ensures the mft
+ * record, and hence the index root attribute, will be written out to disk
+ * later.
+ *
+ * If the index entry is in an index block belonging to the index allocation
+ * attribute, mark the buffers belonging to the index record as well as the
+ * page cache page the index block is in dirty.  This automatically marks the
+ * VFS inode of the ntfs index inode to which the index entry belongs dirty,
+ * too (I_DIRTY_PAGES) and this in turn ensures the page buffers, and hence the
+ * dirty index block, will be written out to disk later.
+ */
+static inline void ntfs_index_entry_mark_dirty(ntfs_index_context *ictx)
+{
+	if (ictx->is_in_root)
+		mark_mft_record_dirty(ictx->actx->ntfs_ino);
+	else
+		mark_ntfs_record_dirty(ictx->page,
+				(u8*)ictx->ia - (u8*)page_address(ictx->page));
+}
+
+#endif /* NTFS_RW */
+
+#endif /* _LINUX_NTFS_INDEX_H */