samsung update 1

1 files changed, 196 insertions, 0 deletions

diff --git a/fs/yaffs2/yaffs_packedtags2.c b/fs/yaffs2/yaffs_packedtags2.c
new file mode 100644
index 0000000..8e7fea3
--- /dev/null
+++ b/fs/yaffs2/yaffs_packedtags2.c
@@ -0,0 +1,196 @@
+/*
+ * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include "yaffs_packedtags2.h"
+#include "yportenv.h"
+#include "yaffs_trace.h"
+#include "yaffs_tagsvalidity.h"
+
+/* This code packs a set of extended tags into a binary structure for
+ * NAND storage
+ */
+
+/* Some of the information is "extra" struff which can be packed in to
+ * speed scanning
+ * This is defined by having the EXTRA_HEADER_INFO_FLAG set.
+ */
+
+/* Extra flags applied to chunk_id */
+
+#define EXTRA_HEADER_INFO_FLAG	0x80000000
+#define EXTRA_SHRINK_FLAG	0x40000000
+#define EXTRA_SHADOWS_FLAG	0x20000000
+#define EXTRA_SPARE_FLAGS	0x10000000
+
+#define ALL_EXTRA_FLAGS		0xF0000000
+
+/* Also, the top 4 bits of the object Id are set to the object type. */
+#define EXTRA_OBJECT_TYPE_SHIFT (28)
+#define EXTRA_OBJECT_TYPE_MASK  ((0x0F) << EXTRA_OBJECT_TYPE_SHIFT)
+
+static void yaffs_dump_packed_tags2_tags_only(const struct
+					      yaffs_packed_tags2_tags_only *ptt)
+{
+	yaffs_trace(YAFFS_TRACE_MTD,
+		"packed tags obj %d chunk %d byte %d seq %d",
+		ptt->obj_id, ptt->chunk_id, ptt->n_bytes, ptt->seq_number);
+}
+
+static void yaffs_dump_packed_tags2(const struct yaffs_packed_tags2 *pt)
+{
+	yaffs_dump_packed_tags2_tags_only(&pt->t);
+}
+
+static void yaffs_dump_tags2(const struct yaffs_ext_tags *t)
+{
+	yaffs_trace(YAFFS_TRACE_MTD,
+		"ext.tags eccres %d blkbad %d chused %d obj %d chunk%d byte %d del %d ser %d seq %d",
+		t->ecc_result, t->block_bad, t->chunk_used, t->obj_id,
+		t->chunk_id, t->n_bytes, t->is_deleted, t->serial_number,
+		t->seq_number);
+
+}
+
+void yaffs_pack_tags2_tags_only(struct yaffs_packed_tags2_tags_only *ptt,
+				const struct yaffs_ext_tags *t)
+{
+	ptt->chunk_id = t->chunk_id;
+	ptt->seq_number = t->seq_number;
+	ptt->n_bytes = t->n_bytes;
+	ptt->obj_id = t->obj_id;
+
+	if (t->chunk_id == 0 && t->extra_available) {
+		/* Store the extra header info instead */
+		/* We save the parent object in the chunk_id */
+		ptt->chunk_id = EXTRA_HEADER_INFO_FLAG | t->extra_parent_id;
+		if (t->extra_is_shrink)
+			ptt->chunk_id |= EXTRA_SHRINK_FLAG;
+		if (t->extra_shadows)
+			ptt->chunk_id |= EXTRA_SHADOWS_FLAG;
+
+		ptt->obj_id &= ~EXTRA_OBJECT_TYPE_MASK;
+		ptt->obj_id |= (t->extra_obj_type << EXTRA_OBJECT_TYPE_SHIFT);
+
+		if (t->extra_obj_type == YAFFS_OBJECT_TYPE_HARDLINK)
+			ptt->n_bytes = t->extra_equiv_id;
+		else if (t->extra_obj_type == YAFFS_OBJECT_TYPE_FILE)
+			ptt->n_bytes = t->extra_length;
+		else
+			ptt->n_bytes = 0;
+	}
+
+	yaffs_dump_packed_tags2_tags_only(ptt);
+	yaffs_dump_tags2(t);
+}
+
+void yaffs_pack_tags2(struct yaffs_packed_tags2 *pt,
+		      const struct yaffs_ext_tags *t, int tags_ecc)
+{
+	yaffs_pack_tags2_tags_only(&pt->t, t);
+
+	if (tags_ecc)
+		yaffs_ecc_calc_other((unsigned char *)&pt->t,
+				     sizeof(struct
+					    yaffs_packed_tags2_tags_only),
+				     &pt->ecc);
+}
+
+void yaffs_unpack_tags2_tags_only(struct yaffs_ext_tags *t,
+				  struct yaffs_packed_tags2_tags_only *ptt)
+{
+
+	memset(t, 0, sizeof(struct yaffs_ext_tags));
+
+	yaffs_init_tags(t);
+
+	if (ptt->seq_number != 0xFFFFFFFF) {
+		t->block_bad = 0;
+		t->chunk_used = 1;
+		t->obj_id = ptt->obj_id;
+		t->chunk_id = ptt->chunk_id;
+		t->n_bytes = ptt->n_bytes;
+		t->is_deleted = 0;
+		t->serial_number = 0;
+		t->seq_number = ptt->seq_number;
+
+		/* Do extra header info stuff */
+
+		if (ptt->chunk_id & EXTRA_HEADER_INFO_FLAG) {
+			t->chunk_id = 0;
+			t->n_bytes = 0;
+
+			t->extra_available = 1;
+			t->extra_parent_id =
+			    ptt->chunk_id & (~(ALL_EXTRA_FLAGS));
+			t->extra_is_shrink =
+			    (ptt->chunk_id & EXTRA_SHRINK_FLAG) ? 1 : 0;
+			t->extra_shadows =
+			    (ptt->chunk_id & EXTRA_SHADOWS_FLAG) ? 1 : 0;
+			t->extra_obj_type =
+			    ptt->obj_id >> EXTRA_OBJECT_TYPE_SHIFT;
+			t->obj_id &= ~EXTRA_OBJECT_TYPE_MASK;
+
+			if (t->extra_obj_type == YAFFS_OBJECT_TYPE_HARDLINK)
+				t->extra_equiv_id = ptt->n_bytes;
+			else
+				t->extra_length = ptt->n_bytes;
+		}
+	}
+
+	yaffs_dump_packed_tags2_tags_only(ptt);
+	yaffs_dump_tags2(t);
+
+}
+
+void yaffs_unpack_tags2(struct yaffs_ext_tags *t, struct yaffs_packed_tags2 *pt,
+			int tags_ecc)
+{
+
+	enum yaffs_ecc_result ecc_result = YAFFS_ECC_RESULT_NO_ERROR;
+
+	if (pt->t.seq_number != 0xFFFFFFFF && tags_ecc) {
+		/* Chunk is in use and we need to do ECC */
+
+		struct yaffs_ecc_other ecc;
+		int result;
+		yaffs_ecc_calc_other((unsigned char *)&pt->t,
+				     sizeof(struct
+					    yaffs_packed_tags2_tags_only),
+				     &ecc);
+		result =
+		    yaffs_ecc_correct_other((unsigned char *)&pt->t,
+					    sizeof(struct
+						   yaffs_packed_tags2_tags_only),
+					    &pt->ecc, &ecc);
+		switch (result) {
+		case 0:
+			ecc_result = YAFFS_ECC_RESULT_NO_ERROR;
+			break;
+		case 1:
+			ecc_result = YAFFS_ECC_RESULT_FIXED;
+			break;
+		case -1:
+			ecc_result = YAFFS_ECC_RESULT_UNFIXED;
+			break;
+		default:
+			ecc_result = YAFFS_ECC_RESULT_UNKNOWN;
+		}
+	}
+
+	yaffs_unpack_tags2_tags_only(t, &pt->t);
+
+	t->ecc_result = ecc_result;
+
+	yaffs_dump_packed_tags2(pt);
+	yaffs_dump_tags2(t);
+}