root/fs/jffs2/writev.c

DEFINITIONS

1. mtd_fake_writev
2. jffs2_flash_direct_writev
3. jffs2_flash_direct_write

/*
 * JFFS2 -- Journalling Flash File System, Version 2.
 *
 * Copyright © 2001-2007 Red Hat, Inc.
 *
 * Created by David Woodhouse <dwmw2@infradead.org>
 *
 * For licensing information, see the file 'LICENCE' in this directory.
 *
 */

#include <linux/kernel.h>
#include <linux/mtd/mtd.h>
#include "nodelist.h"

/* This ought to be in core MTD code. All registered MTD devices
   without writev should have this put in place. Bug the MTD
   maintainer */
static inline int mtd_fake_writev(struct mtd_info *mtd, const struct kvec *vecs,
                                  unsigned long count, loff_t to, size_t *retlen)
{
        unsigned long i;
        size_t totlen = 0, thislen;
        int ret = 0;

        for (i=0; i<count; i++) {
                if (!vecs[i].iov_len)
                        continue;
                ret = mtd->write(mtd, to, vecs[i].iov_len, &thislen, vecs[i].iov_base);
                totlen += thislen;
                if (ret || thislen != vecs[i].iov_len)
                        break;
                to += vecs[i].iov_len;
        }
        if (retlen)
                *retlen = totlen;
        return ret;
}

int jffs2_flash_direct_writev(struct jffs2_sb_info *c, const struct kvec *vecs,
                              unsigned long count, loff_t to, size_t *retlen)
{
        if (!jffs2_is_writebuffered(c)) {
                if (jffs2_sum_active()) {
                        int res;
                        res = jffs2_sum_add_kvec(c, vecs, count, (uint32_t) to);
                        if (res) {
                                return res;
                        }
                }
        }

        if (c->mtd->writev)
                return c->mtd->writev(c->mtd, vecs, count, to, retlen);
        else {
                return mtd_fake_writev(c->mtd, vecs, count, to, retlen);
        }
}

int jffs2_flash_direct_write(struct jffs2_sb_info *c, loff_t ofs, size_t len,
                        size_t *retlen, const u_char *buf)
{
        int ret;
        ret = c->mtd->write(c->mtd, ofs, len, retlen, buf);

        if (jffs2_sum_active()) {
                struct kvec vecs[1];
                int res;

                vecs[0].iov_base = (unsigned char *) buf;
                vecs[0].iov_len = len;

                res = jffs2_sum_add_kvec(c, vecs, 1, (uint32_t) ofs);
                if (res) {
                        return res;
                }
        }
        return ret;
}