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Subject[PATCH 3/9] Add yaffs checkpointing, blockinfo, nameval and os context
Date
From: Charles Manning <cdhmanning@gmail.com>

Adding yaffs2 file system.

Signed-off-by: Charles Manning <cdhmanning@gmail.com>
---
fs/yaffs2/yaffs_checkptrw.c | 419 ++++++++++++++++++++++++++++++++++++++++
fs/yaffs2/yaffs_checkptrw.h | 33 +++
fs/yaffs2/yaffs_getblockinfo.h | 36 ++++
fs/yaffs2/yaffs_linux.h | 41 ++++
fs/yaffs2/yaffs_nameval.c | 199 +++++++++++++++++++
fs/yaffs2/yaffs_nameval.h | 28 +++
6 files changed, 756 insertions(+), 0 deletions(-)
create mode 100644 fs/yaffs2/yaffs_checkptrw.c
create mode 100644 fs/yaffs2/yaffs_checkptrw.h
create mode 100644 fs/yaffs2/yaffs_getblockinfo.h
create mode 100644 fs/yaffs2/yaffs_linux.h
create mode 100644 fs/yaffs2/yaffs_nameval.c
create mode 100644 fs/yaffs2/yaffs_nameval.h
diff --git a/fs/yaffs2/yaffs_checkptrw.c b/fs/yaffs2/yaffs_checkptrw.c
new file mode 100644
index 0000000..2cb144c
--- /dev/null
+++ b/fs/yaffs2/yaffs_checkptrw.c
@@ -0,0 +1,419 @@
+/*
+ * 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_checkptrw.h"
+#include "yaffs_getblockinfo.h"
+
+static int yaffs2_checkpt_space_ok(struct yaffs_dev *dev)
+{
+ int blocks_avail = dev->n_erased_blocks - dev->param.n_reserved_blocks;
+
+ T(YAFFS_TRACE_CHECKPOINT,
+ (TSTR("checkpt blocks available = %d" TENDSTR), blocks_avail));
+
+ return (blocks_avail <= 0) ? 0 : 1;
+}
+
+static int yaffs_checkpt_erase(struct yaffs_dev *dev)
+{
+ int i;
+
+ if (!dev->param.erase_fn)
+ return 0;
+ T(YAFFS_TRACE_CHECKPOINT, (TSTR("checking blocks %d to %d" TENDSTR),
+ dev->internal_start_block,
+ dev->internal_end_block));
+
+ for (i = dev->internal_start_block; i <= dev->internal_end_block; i++) {
+ struct yaffs_block_info *bi = yaffs_get_block_info(dev, i);
+ if (bi->block_state == YAFFS_BLOCK_STATE_CHECKPOINT) {
+ T(YAFFS_TRACE_CHECKPOINT,
+ (TSTR("erasing checkpt block %d" TENDSTR), i));
+
+ dev->n_erasures++;
+
+ if (dev->param.
+ erase_fn(dev,
+ i - dev->block_offset /* realign */ )) {
+ bi->block_state = YAFFS_BLOCK_STATE_EMPTY;
+ dev->n_erased_blocks++;
+ dev->n_free_chunks +=
+ dev->param.chunks_per_block;
+ } else {
+ dev->param.bad_block_fn(dev, i);
+ bi->block_state = YAFFS_BLOCK_STATE_DEAD;
+ }
+ }
+ }
+
+ dev->blocks_in_checkpt = 0;
+
+ return 1;
+}
+
+static void yaffs2_checkpt_find_erased_block(struct yaffs_dev *dev)
+{
+ int i;
+ int blocks_avail = dev->n_erased_blocks - dev->param.n_reserved_blocks;
+ T(YAFFS_TRACE_CHECKPOINT,
+ (TSTR
+ ("allocating checkpt block: erased %d reserved %d avail %d next %d "
+ TENDSTR), dev->n_erased_blocks, dev->param.n_reserved_blocks,
+ blocks_avail, dev->checkpt_next_block));
+
+ if (dev->checkpt_next_block >= 0 &&
+ dev->checkpt_next_block <= dev->internal_end_block &&
+ blocks_avail > 0) {
+
+ for (i = dev->checkpt_next_block; i <= dev->internal_end_block;
+ i++) {
+ struct yaffs_block_info *bi =
+ yaffs_get_block_info(dev, i);
+ if (bi->block_state == YAFFS_BLOCK_STATE_EMPTY) {
+ dev->checkpt_next_block = i + 1;
+ dev->checkpt_cur_block = i;
+ T(YAFFS_TRACE_CHECKPOINT,
+ (TSTR("allocating checkpt block %d" TENDSTR),
+ i));
+ return;
+ }
+ }
+ }
+ T(YAFFS_TRACE_CHECKPOINT, (TSTR("out of checkpt blocks" TENDSTR)));
+
+ dev->checkpt_next_block = -1;
+ dev->checkpt_cur_block = -1;
+}
+
+static void yaffs2_checkpt_find_block(struct yaffs_dev *dev)
+{
+ int i;
+ struct yaffs_ext_tags tags;
+
+ T(YAFFS_TRACE_CHECKPOINT,
+ (TSTR("find next checkpt block: start: blocks %d next %d" TENDSTR),
+ dev->blocks_in_checkpt, dev->checkpt_next_block));
+
+ if (dev->blocks_in_checkpt < dev->checkpt_max_blocks)
+ for (i = dev->checkpt_next_block; i <= dev->internal_end_block;
+ i++) {
+ int chunk = i * dev->param.chunks_per_block;
+ int realigned_chunk = chunk - dev->chunk_offset;
+
+ dev->param.read_chunk_tags_fn(dev, realigned_chunk,
+ NULL, &tags);
+ T(YAFFS_TRACE_CHECKPOINT,
+ (TSTR
+ ("find next checkpt block: search: block %d oid %d seq %d eccr %d"
+ TENDSTR), i, tags.obj_id, tags.seq_number,
+ tags.ecc_result));
+
+ if (tags.seq_number == YAFFS_SEQUENCE_CHECKPOINT_DATA) {
+ /* Right kind of block */
+ dev->checkpt_next_block = tags.obj_id;
+ dev->checkpt_cur_block = i;
+ dev->checkpt_block_list[dev->
+ blocks_in_checkpt] = i;
+ dev->blocks_in_checkpt++;
+ T(YAFFS_TRACE_CHECKPOINT,
+ (TSTR("found checkpt block %d" TENDSTR), i));
+ return;
+ }
+ }
+
+ T(YAFFS_TRACE_CHECKPOINT,
+ (TSTR("found no more checkpt blocks" TENDSTR)));
+
+ dev->checkpt_next_block = -1;
+ dev->checkpt_cur_block = -1;
+}
+
+int yaffs2_checkpt_open(struct yaffs_dev *dev, int writing)
+{
+
+ dev->checkpt_open_write = writing;
+
+ /* Got the functions we need? */
+ if (!dev->param.write_chunk_tags_fn ||
+ !dev->param.read_chunk_tags_fn ||
+ !dev->param.erase_fn || !dev->param.bad_block_fn)
+ return 0;
+
+ if (writing && !yaffs2_checkpt_space_ok(dev))
+ return 0;
+
+ if (!dev->checkpt_buffer)
+ dev->checkpt_buffer =
+ YMALLOC_DMA(dev->param.total_bytes_per_chunk);
+ if (!dev->checkpt_buffer)
+ return 0;
+
+ dev->checkpt_page_seq = 0;
+ dev->checkpt_byte_count = 0;
+ dev->checkpt_sum = 0;
+ dev->checkpt_xor = 0;
+ dev->checkpt_cur_block = -1;
+ dev->checkpt_cur_chunk = -1;
+ dev->checkpt_next_block = dev->internal_start_block;
+
+ /* Erase all the blocks in the checkpoint area */
+ if (writing) {
+ memset(dev->checkpt_buffer, 0, dev->data_bytes_per_chunk);
+ dev->checkpt_byte_offs = 0;
+ return yaffs_checkpt_erase(dev);
+ } else {
+ int i;
+ /* Set to a value that will kick off a read */
+ dev->checkpt_byte_offs = dev->data_bytes_per_chunk;
+ /* A checkpoint block list of 1 checkpoint block per 16 block is (hopefully)
+ * going to be way more than we need */
+ dev->blocks_in_checkpt = 0;
+ dev->checkpt_max_blocks =
+ (dev->internal_end_block - dev->internal_start_block) / 16 +
+ 2;
+ dev->checkpt_block_list =
+ YMALLOC(sizeof(int) * dev->checkpt_max_blocks);
+ if (!dev->checkpt_block_list)
+ return 0;
+
+ for (i = 0; i < dev->checkpt_max_blocks; i++)
+ dev->checkpt_block_list[i] = -1;
+ }
+
+ return 1;
+}
+
+int yaffs2_get_checkpt_sum(struct yaffs_dev *dev, u32 * sum)
+{
+ u32 composite_sum;
+ composite_sum = (dev->checkpt_sum << 8) | (dev->checkpt_xor & 0xFF);
+ *sum = composite_sum;
+ return 1;
+}
+
+static int yaffs2_checkpt_flush_buffer(struct yaffs_dev *dev)
+{
+ int chunk;
+ int realigned_chunk;
+
+ struct yaffs_ext_tags tags;
+
+ if (dev->checkpt_cur_block < 0) {
+ yaffs2_checkpt_find_erased_block(dev);
+ dev->checkpt_cur_chunk = 0;
+ }
+
+ if (dev->checkpt_cur_block < 0)
+ return 0;
+
+ tags.is_deleted = 0;
+ tags.obj_id = dev->checkpt_next_block; /* Hint to next place to look */
+ tags.chunk_id = dev->checkpt_page_seq + 1;
+ tags.seq_number = YAFFS_SEQUENCE_CHECKPOINT_DATA;
+ tags.n_bytes = dev->data_bytes_per_chunk;
+ if (dev->checkpt_cur_chunk == 0) {
+ /* First chunk we write for the block? Set block state to
+ checkpoint */
+ struct yaffs_block_info *bi =
+ yaffs_get_block_info(dev, dev->checkpt_cur_block);
+ bi->block_state = YAFFS_BLOCK_STATE_CHECKPOINT;
+ dev->blocks_in_checkpt++;
+ }
+
+ chunk =
+ dev->checkpt_cur_block * dev->param.chunks_per_block +
+ dev->checkpt_cur_chunk;
+
+ T(YAFFS_TRACE_CHECKPOINT,
+ (TSTR
+ ("checkpoint wite buffer nand %d(%d:%d) objid %d chId %d" TENDSTR),
+ chunk, dev->checkpt_cur_block, dev->checkpt_cur_chunk, tags.obj_id,
+ tags.chunk_id));
+
+ realigned_chunk = chunk - dev->chunk_offset;
+
+ dev->n_page_writes++;
+
+ dev->param.write_chunk_tags_fn(dev, realigned_chunk,
+ dev->checkpt_buffer, &tags);
+ dev->checkpt_byte_offs = 0;
+ dev->checkpt_page_seq++;
+ dev->checkpt_cur_chunk++;
+ if (dev->checkpt_cur_chunk >= dev->param.chunks_per_block) {
+ dev->checkpt_cur_chunk = 0;
+ dev->checkpt_cur_block = -1;
+ }
+ memset(dev->checkpt_buffer, 0, dev->data_bytes_per_chunk);
+
+ return 1;
+}
+
+int yaffs2_checkpt_wr(struct yaffs_dev *dev, const void *data, int n_bytes)
+{
+ int i = 0;
+ int ok = 1;
+
+ u8 *data_bytes = (u8 *) data;
+
+ if (!dev->checkpt_buffer)
+ return 0;
+
+ if (!dev->checkpt_open_write)
+ return -1;
+
+ while (i < n_bytes && ok) {
+ dev->checkpt_buffer[dev->checkpt_byte_offs] = *data_bytes;
+ dev->checkpt_sum += *data_bytes;
+ dev->checkpt_xor ^= *data_bytes;
+
+ dev->checkpt_byte_offs++;
+ i++;
+ data_bytes++;
+ dev->checkpt_byte_count++;
+
+ if (dev->checkpt_byte_offs < 0 ||
+ dev->checkpt_byte_offs >= dev->data_bytes_per_chunk)
+ ok = yaffs2_checkpt_flush_buffer(dev);
+ }
+
+ return i;
+}
+
+int yaffs2_checkpt_rd(struct yaffs_dev *dev, void *data, int n_bytes)
+{
+ int i = 0;
+ int ok = 1;
+ struct yaffs_ext_tags tags;
+
+ int chunk;
+ int realigned_chunk;
+
+ u8 *data_bytes = (u8 *) data;
+
+ if (!dev->checkpt_buffer)
+ return 0;
+
+ if (dev->checkpt_open_write)
+ return -1;
+
+ while (i < n_bytes && ok) {
+
+ if (dev->checkpt_byte_offs < 0 ||
+ dev->checkpt_byte_offs >= dev->data_bytes_per_chunk) {
+
+ if (dev->checkpt_cur_block < 0) {
+ yaffs2_checkpt_find_block(dev);
+ dev->checkpt_cur_chunk = 0;
+ }
+
+ if (dev->checkpt_cur_block < 0)
+ ok = 0;
+ else {
+ chunk = dev->checkpt_cur_block *
+ dev->param.chunks_per_block +
+ dev->checkpt_cur_chunk;
+
+ realigned_chunk = chunk - dev->chunk_offset;
+
+ dev->n_page_reads++;
+
+ /* read in the next chunk */
+ dev->param.read_chunk_tags_fn(dev,
+ realigned_chunk,
+ dev->
+ checkpt_buffer,
+ &tags);
+
+ if (tags.chunk_id != (dev->checkpt_page_seq + 1)
+ || tags.ecc_result > YAFFS_ECC_RESULT_FIXED
+ || tags.seq_number !=
+ YAFFS_SEQUENCE_CHECKPOINT_DATA)
+ ok = 0;
+
+ dev->checkpt_byte_offs = 0;
+ dev->checkpt_page_seq++;
+ dev->checkpt_cur_chunk++;
+
+ if (dev->checkpt_cur_chunk >=
+ dev->param.chunks_per_block)
+ dev->checkpt_cur_block = -1;
+ }
+ }
+
+ if (ok) {
+ *data_bytes =
+ dev->checkpt_buffer[dev->checkpt_byte_offs];
+ dev->checkpt_sum += *data_bytes;
+ dev->checkpt_xor ^= *data_bytes;
+ dev->checkpt_byte_offs++;
+ i++;
+ data_bytes++;
+ dev->checkpt_byte_count++;
+ }
+ }
+
+ return i;
+}
+
+int yaffs_checkpt_close(struct yaffs_dev *dev)
+{
+
+ if (dev->checkpt_open_write) {
+ if (dev->checkpt_byte_offs != 0)
+ yaffs2_checkpt_flush_buffer(dev);
+ } else if (dev->checkpt_block_list) {
+ int i;
+ for (i = 0;
+ i < dev->blocks_in_checkpt
+ && dev->checkpt_block_list[i] >= 0; i++) {
+ int blk = dev->checkpt_block_list[i];
+ struct yaffs_block_info *bi = NULL;
+ if (dev->internal_start_block <= blk
+ && blk <= dev->internal_end_block)
+ bi = yaffs_get_block_info(dev, blk);
+ if (bi && bi->block_state == YAFFS_BLOCK_STATE_EMPTY)
+ bi->block_state = YAFFS_BLOCK_STATE_CHECKPOINT;
+ else {
+ /* Todo this looks odd... */
+ }
+ }
+ YFREE(dev->checkpt_block_list);
+ dev->checkpt_block_list = NULL;
+ }
+
+ dev->n_free_chunks -=
+ dev->blocks_in_checkpt * dev->param.chunks_per_block;
+ dev->n_erased_blocks -= dev->blocks_in_checkpt;
+
+ T(YAFFS_TRACE_CHECKPOINT, (TSTR("checkpoint byte count %d" TENDSTR),
+ dev->checkpt_byte_count));
+
+ if (dev->checkpt_buffer) {
+ /* free the buffer */
+ YFREE(dev->checkpt_buffer);
+ dev->checkpt_buffer = NULL;
+ return 1;
+ } else
+ return 0;
+}
+
+int yaffs2_checkpt_invalidate_stream(struct yaffs_dev *dev)
+{
+ /* Erase the checkpoint data */
+
+ T(YAFFS_TRACE_CHECKPOINT,
+ (TSTR("checkpoint invalidate of %d blocks" TENDSTR),
+ dev->blocks_in_checkpt));
+
+ return yaffs_checkpt_erase(dev);
+}
diff --git a/fs/yaffs2/yaffs_checkptrw.h b/fs/yaffs2/yaffs_checkptrw.h
new file mode 100644
index 0000000..361c606
--- /dev/null
+++ b/fs/yaffs2/yaffs_checkptrw.h
@@ -0,0 +1,33 @@
+/*
+ * 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 Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+#ifndef __YAFFS_CHECKPTRW_H__
+#define __YAFFS_CHECKPTRW_H__
+
+#include "yaffs_guts.h"
+
+int yaffs2_checkpt_open(struct yaffs_dev *dev, int writing);
+
+int yaffs2_checkpt_wr(struct yaffs_dev *dev, const void *data, int n_bytes);
+
+int yaffs2_checkpt_rd(struct yaffs_dev *dev, void *data, int n_bytes);
+
+int yaffs2_get_checkpt_sum(struct yaffs_dev *dev, u32 * sum);
+
+int yaffs_checkpt_close(struct yaffs_dev *dev);
+
+int yaffs2_checkpt_invalidate_stream(struct yaffs_dev *dev);
+
+#endif
diff --git a/fs/yaffs2/yaffs_getblockinfo.h b/fs/yaffs2/yaffs_getblockinfo.h
new file mode 100644
index 0000000..108c361
--- /dev/null
+++ b/fs/yaffs2/yaffs_getblockinfo.h
@@ -0,0 +1,36 @@
+/*
+ * 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 Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+#ifndef __YAFFS_GETBLOCKINFO_H__
+#define __YAFFS_GETBLOCKINFO_H__
+
+#include "yaffs_guts.h"
+#include "yaffs_trace.h"
+
+/* Function to manipulate block info */
+static Y_INLINE struct yaffs_block_info *yaffs_get_block_info(struct yaffs_dev
+ *dev, int blk)
+{
+ if (blk < dev->internal_start_block || blk > dev->internal_end_block) {
+ T(YAFFS_TRACE_ERROR,
+ (TSTR
+ ("**>> yaffs: get_block_info block %d is not valid" TENDSTR),
+ blk));
+ YBUG();
+ }
+ return &dev->block_info[blk - dev->internal_start_block];
+}
+
+#endif
diff --git a/fs/yaffs2/yaffs_linux.h b/fs/yaffs2/yaffs_linux.h
new file mode 100644
index 0000000..3b508cb
--- /dev/null
+++ b/fs/yaffs2/yaffs_linux.h
@@ -0,0 +1,41 @@
+/*
+ * 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 Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+#ifndef __YAFFS_LINUX_H__
+#define __YAFFS_LINUX_H__
+
+#include "yportenv.h"
+
+struct yaffs_linux_context {
+ struct list_head context_list; /* List of these we have mounted */
+ struct yaffs_dev *dev;
+ struct super_block *super;
+ struct task_struct *bg_thread; /* Background thread for this device */
+ int bg_running;
+ struct mutex gross_lock; /* Gross locking mutex*/
+ u8 *spare_buffer; /* For mtdif2 use. Don't know the size of the buffer
+ * at compile time so we have to allocate it.
+ */
+ struct list_head search_contexts;
+ void (*put_super_fn) (struct super_block * sb);
+
+ struct task_struct *readdir_process;
+ unsigned mount_id;
+};
+
+#define yaffs_dev_to_lc(dev) ((struct yaffs_linux_context *)((dev)->os_context))
+#define yaffs_dev_to_mtd(dev) ((struct mtd_info *)((dev)->driver_context))
+
+#endif
diff --git a/fs/yaffs2/yaffs_nameval.c b/fs/yaffs2/yaffs_nameval.c
new file mode 100644
index 0000000..d7cb72a
--- /dev/null
+++ b/fs/yaffs2/yaffs_nameval.c
@@ -0,0 +1,199 @@
+/*
+ * 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.
+ */
+
+/*
+ * This simple implementation of a name-value store assumes a small number of values and fits
+ * into a small finite buffer.
+ *
+ * Each attribute is stored as a record:
+ * sizeof(int) bytes record size.
+ * strnlen+1 bytes name null terminated.
+ * nbytes value.
+ * ----------
+ * total size stored in record size
+ *
+ * This code has not been tested with unicode yet.
+ */
+
+#include "yaffs_nameval.h"
+
+#include "yportenv.h"
+
+static int nval_find(const char *xb, int xb_size, const YCHAR * name,
+ int *exist_size)
+{
+ int pos = 0;
+ int size;
+
+ memcpy(&size, xb, sizeof(int));
+ while (size > 0 && (size < xb_size) && (pos + size < xb_size)) {
+ if (yaffs_strncmp
+ ((YCHAR *) (xb + pos + sizeof(int)), name, size) == 0) {
+ if (exist_size)
+ *exist_size = size;
+ return pos;
+ }
+ pos += size;
+ if (pos < xb_size - sizeof(int))
+ memcpy(&size, xb + pos, sizeof(int));
+ else
+ size = 0;
+ }
+ if (exist_size)
+ *exist_size = 0;
+ return -1;
+}
+
+static int nval_used(const char *xb, int xb_size)
+{
+ int pos = 0;
+ int size;
+
+ memcpy(&size, xb + pos, sizeof(int));
+ while (size > 0 && (size < xb_size) && (pos + size < xb_size)) {
+ pos += size;
+ if (pos < xb_size - sizeof(int))
+ memcpy(&size, xb + pos, sizeof(int));
+ else
+ size = 0;
+ }
+ return pos;
+}
+
+int nval_del(char *xb, int xb_size, const YCHAR * name)
+{
+ int pos = nval_find(xb, xb_size, name, NULL);
+ int size;
+
+ if (pos >= 0 && pos < xb_size) {
+ /* Find size, shift rest over this record, then zero out the rest of buffer */
+ memcpy(&size, xb + pos, sizeof(int));
+ memcpy(xb + pos, xb + pos + size, xb_size - (pos + size));
+ memset(xb + (xb_size - size), 0, size);
+ return 0;
+ } else
+ return -ENODATA;
+}
+
+int nval_set(char *xb, int xb_size, const YCHAR * name, const char *buf,
+ int bsize, int flags)
+{
+ int pos;
+ int namelen = yaffs_strnlen(name, xb_size);
+ int reclen;
+ int size_exist = 0;
+ int space;
+ int start;
+
+ pos = nval_find(xb, xb_size, name, &size_exist);
+
+ if (flags & XATTR_CREATE && pos >= 0)
+ return -EEXIST;
+ if (flags & XATTR_REPLACE && pos < 0)
+ return -ENODATA;
+
+ start = nval_used(xb, xb_size);
+ space = xb_size - start + size_exist;
+
+ reclen = (sizeof(int) + namelen + 1 + bsize);
+
+ if (reclen > space)
+ return -ENOSPC;
+
+ if (pos >= 0) {
+ nval_del(xb, xb_size, name);
+ start = nval_used(xb, xb_size);
+ }
+
+ pos = start;
+
+ memcpy(xb + pos, &reclen, sizeof(int));
+ pos += sizeof(int);
+ yaffs_strncpy((YCHAR *) (xb + pos), name, reclen);
+ pos += (namelen + 1);
+ memcpy(xb + pos, buf, bsize);
+ return 0;
+}
+
+int nval_get(const char *xb, int xb_size, const YCHAR * name, char *buf,
+ int bsize)
+{
+ int pos = nval_find(xb, xb_size, name, NULL);
+ int size;
+
+ if (pos >= 0 && pos < xb_size) {
+
+ memcpy(&size, xb + pos, sizeof(int));
+ pos += sizeof(int); /* advance past record length */
+ size -= sizeof(int);
+
+ /* Advance over name string */
+ while (xb[pos] && size > 0 && pos < xb_size) {
+ pos++;
+ size--;
+ }
+ /*Advance over NUL */
+ pos++;
+ size--;
+
+ if (size <= bsize) {
+ memcpy(buf, xb + pos, size);
+ return size;
+ }
+
+ }
+ if (pos >= 0)
+ return -ERANGE;
+ else
+ return -ENODATA;
+}
+
+int nval_list(const char *xb, int xb_size, char *buf, int bsize)
+{
+ int pos = 0;
+ int size;
+ int name_len;
+ int ncopied = 0;
+ int filled = 0;
+
+ memcpy(&size, xb + pos, sizeof(int));
+ while (size > sizeof(int) && size <= xb_size && (pos + size) < xb_size
+ && !filled) {
+ pos += sizeof(int);
+ size -= sizeof(int);
+ name_len = yaffs_strnlen((YCHAR *) (xb + pos), size);
+ if (ncopied + name_len + 1 < bsize) {
+ memcpy(buf, xb + pos, name_len * sizeof(YCHAR));
+ buf += name_len;
+ *buf = '\0';
+ buf++;
+ if (sizeof(YCHAR) > 1) {
+ *buf = '\0';
+ buf++;
+ }
+ ncopied += (name_len + 1);
+ } else
+ filled = 1;
+ pos += size;
+ if (pos < xb_size - sizeof(int))
+ memcpy(&size, xb + pos, sizeof(int));
+ else
+ size = 0;
+ }
+ return ncopied;
+}
+
+int nval_hasvalues(const char *xb, int xb_size)
+{
+ return nval_used(xb, xb_size) > 0;
+}
diff --git a/fs/yaffs2/yaffs_nameval.h b/fs/yaffs2/yaffs_nameval.h
new file mode 100644
index 0000000..2bb02b6
--- /dev/null
+++ b/fs/yaffs2/yaffs_nameval.h
@@ -0,0 +1,28 @@
+/*
+ * 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 Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+#ifndef __NAMEVAL_H__
+#define __NAMEVAL_H__
+
+#include "yportenv.h"
+
+int nval_del(char *xb, int xb_size, const YCHAR * name);
+int nval_set(char *xb, int xb_size, const YCHAR * name, const char *buf,
+ int bsize, int flags);
+int nval_get(const char *xb, int xb_size, const YCHAR * name, char *buf,
+ int bsize);
+int nval_list(const char *xb, int xb_size, char *buf, int bsize);
+int nval_hasvalues(const char *xb, int xb_size);
+#endif
--
1.7.1


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