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#include "rtems-jffs2-config.h"
/*
* JFFS2 -- Journalling Flash File System, Version 2.
*
* Copyright (C) 2001-2003 Red Hat, Inc.
*
* Created by Dominic Ostrowski <dominic.ostrowski@3glab.com>
* Contributors: David Woodhouse, Nick Garnett, Richard Panton.
*
* For licensing information, see the file 'LICENCE' in this directory.
*
* $Id: flashio.c,v 1.1 2003/11/26 14:09:29 dwmw2 Exp $
*
*/
#include <linux/kernel.h>
#include "nodelist.h"
int jffs2_flash_read(struct jffs2_sb_info * c,
cyg_uint32 read_buffer_offset, const size_t size,
size_t * return_size, unsigned char *write_buffer)
{
const struct super_block *sb = OFNI_BS_2SFFJ(c);
rtems_jffs2_flash_control *fc = sb->s_flash_control;
*return_size = size;
return (*fc->read)(fc, read_buffer_offset, write_buffer, size);
}
int jffs2_flash_write(struct jffs2_sb_info * c,
cyg_uint32 write_buffer_offset, const size_t size,
size_t * return_size, unsigned char *read_buffer)
{
const struct super_block *sb = OFNI_BS_2SFFJ(c);
rtems_jffs2_flash_control *fc = sb->s_flash_control;
*return_size = size;
return (*fc->write)(fc, write_buffer_offset, read_buffer, size);
}
int
jffs2_flash_direct_writev(struct jffs2_sb_info *c, const struct iovec *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++) {
// writes need to be aligned but the data we're passed may not be
// Observation suggests most unaligned writes are small, so we
// optimize for that case.
if (((vecs[i].iov_len & (sizeof (int) - 1))) ||
(((unsigned long) vecs[i].
iov_base & (sizeof (unsigned long) - 1)))) {
// are there iov's after this one? Or is it so much we'd need
// to do multiple writes anyway?
if ((i + 1) < count || vecs[i].iov_len > 256) {
// cop out and malloc
unsigned long j;
ssize_t sizetomalloc = 0, totvecsize = 0;
char *cbuf, *cbufptr;
for (j = i; j < count; j++)
totvecsize += vecs[j].iov_len;
// pad up in case unaligned
sizetomalloc = totvecsize + sizeof (int) - 1;
sizetomalloc &= ~(sizeof (int) - 1);
cbuf = (char *) malloc(sizetomalloc);
// malloc returns aligned memory
if (!cbuf) {
ret = -ENOMEM;
goto writev_out;
}
cbufptr = cbuf;
for (j = i; j < count; j++) {
memcpy(cbufptr, vecs[j].iov_base,
vecs[j].iov_len);
cbufptr += vecs[j].iov_len;
}
ret =
jffs2_flash_write(c, to, sizetomalloc,
&thislen, cbuf);
if (thislen > totvecsize) // in case it was aligned up
thislen = totvecsize;
totlen += thislen;
free(cbuf);
goto writev_out;
} else {
// otherwise optimize for the common case
int buf[256 / sizeof (int)]; // int, so int aligned
size_t lentowrite;
lentowrite = vecs[i].iov_len;
// pad up in case its unaligned
lentowrite += sizeof (int) - 1;
lentowrite &= ~(sizeof (int) - 1);
memcpy(buf, vecs[i].iov_base, lentowrite);
ret =
jffs2_flash_write(c, to, lentowrite,
&thislen, (char *) &buf);
if (thislen > vecs[i].iov_len)
thislen = vecs[i].iov_len;
} // else
} else
ret =
jffs2_flash_write(c, 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;
}
writev_out:
if (retlen)
*retlen = totlen;
return ret;
}
int jffs2_flash_erase(struct jffs2_sb_info * c,
struct jffs2_eraseblock * jeb)
{
const struct super_block *sb = OFNI_BS_2SFFJ(c);
rtems_jffs2_flash_control *fc = sb->s_flash_control;
return (*fc->erase)(fc, jeb->offset);
}
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