/**
* ubifs_wbuf_sync_nolock - synchronize write-buffer.
* @wbuf: write-buffer to synchronize
*
* This function synchronizes write-buffer @buf and returns zero in case of
* success or a negative error code in case of failure.
*/
int ubifs_wbuf_sync_nolock(struct ubifs_wbuf *wbuf)
{
struct ubifs_info *c = wbuf->c;
int err, dirt;
cancel_wbuf_timer_nolock(wbuf);
if (!wbuf->used || wbuf->lnum == -1)
/* Write-buffer is empty or not seeked */
return 0;
dbg_io("LEB %d:%d, %d bytes",
wbuf->lnum, wbuf->offs, wbuf->used);
ubifs_assert(!(c->vfs_sb->s_flags & MS_RDONLY));
ubifs_assert(!(wbuf->avail & 7));
ubifs_assert(wbuf->offs + c->min_io_size <= c->leb_size);
if (c->ro_media)
return -EROFS;
ubifs_pad(c, wbuf->buf + wbuf->used, wbuf->avail);
err = ubi_leb_write(c->ubi, wbuf->lnum, wbuf->buf, wbuf->offs,
c->min_io_size, wbuf->dtype);
if (err) {
ubifs_err("cannot write %d bytes to LEB %d:%d",
c->min_io_size, wbuf->lnum, wbuf->offs);
dbg_dump_stack();
return err;
}
dirt = wbuf->avail;
spin_lock(&wbuf->lock);
wbuf->offs += c->min_io_size;
wbuf->avail = c->min_io_size;
wbuf->used = 0;
wbuf->next_ino = 0;
spin_unlock(&wbuf->lock);
if (wbuf->sync_callback)
err = wbuf->sync_callback(c, wbuf->lnum,
c->leb_size - wbuf->offs, dirt);
return err;
}
/**
* ubifs_prepare_node - prepare node to be written to flash.
* @c: UBIFS file-system description object
* @node: the node to pad
* @len: node length
* @pad: if the buffer has to be padded
*
* This function prepares node at @node to be written to the media - it
* calculates node CRC, fills the common header, and adds proper padding up to
* the next minimum I/O unit if @pad is not zero.
*/
void ubifs_prepare_node(struct ubifs_info *c, void *node, int len, int pad)
{
uint32_t crc;
struct ubifs_ch *ch = node;
unsigned long long sqnum = next_sqnum(c);
ubifs_assert(len >= UBIFS_CH_SZ);
ch->magic = cpu_to_le32(UBIFS_NODE_MAGIC);
ch->len = cpu_to_le32(len);
ch->group_type = UBIFS_NO_NODE_GROUP;
ch->sqnum = cpu_to_le64(sqnum);
ch->padding[0] = ch->padding[1] = 0;
crc = crc32(UBIFS_CRC32_INIT, node + 8, len - 8);
ch->crc = cpu_to_le32(crc);
if (pad) {
len = ALIGN(len, 8);
pad = ALIGN(len, c->min_io_size) - len;
ubifs_pad(c, node + len, pad);
}
}
/**
* ubifs_wbuf_sync_nolock - synchronize write-buffer.
* @wbuf: write-buffer to synchronize
*
* This function synchronizes write-buffer @buf and returns zero in case of
* success or a negative error code in case of failure.
*
* Note, although write-buffers are of @c->max_write_size, this function does
* not necessarily writes all @c->max_write_size bytes to the flash. Instead,
* if the write-buffer is only partially filled with data, only the used part
* of the write-buffer (aligned on @c->min_io_size boundary) is synchronized.
* This way we waste less space.
*/
int ubifs_wbuf_sync_nolock(struct ubifs_wbuf *wbuf)
{
struct ubifs_info *c = wbuf->c;
int err, dirt, sync_len;
cancel_wbuf_timer_nolock(wbuf);
if (!wbuf->used || wbuf->lnum == -1)
/* Write-buffer is empty or not seeked */
return 0;
dbg_io("LEB %d:%d, %d bytes, jhead %s",
wbuf->lnum, wbuf->offs, wbuf->used, dbg_jhead(wbuf->jhead));
ubifs_assert(!(wbuf->avail & 7));
ubifs_assert(wbuf->offs + wbuf->size <= c->leb_size);
ubifs_assert(wbuf->size >= c->min_io_size);
ubifs_assert(wbuf->size <= c->max_write_size);
ubifs_assert(wbuf->size % c->min_io_size == 0);
ubifs_assert(!c->ro_media && !c->ro_mount);
if (c->leb_size - wbuf->offs >= c->max_write_size)
ubifs_assert(!((wbuf->offs + wbuf->size) % c->max_write_size));
if (c->ro_error)
return -EROFS;
/*
* Do not write whole write buffer but write only the minimum necessary
* amount of min. I/O units.
*/
sync_len = ALIGN(wbuf->used, c->min_io_size);
dirt = sync_len - wbuf->used;
if (dirt)
ubifs_pad(c, wbuf->buf + wbuf->used, dirt);
#if defined(FEATURE_UBIFS_PERF_INDEX)
if(wbuf->jhead == DATAHD)
err = ubifs_leb_write_log(c, wbuf->lnum, wbuf->buf, wbuf->offs, sync_len);
else
#endif
err = ubifs_leb_write(c, wbuf->lnum, wbuf->buf, wbuf->offs, sync_len);
if (err)
return err;
wbuf->w_count += sync_len; //MTK
spin_lock(&wbuf->lock);
wbuf->offs += sync_len;
/*
* Now @wbuf->offs is not necessarily aligned to @c->max_write_size.
* But our goal is to optimize writes and make sure we write in
* @c->max_write_size chunks and to @c->max_write_size-aligned offset.
* Thus, if @wbuf->offs is not aligned to @c->max_write_size now, make
* sure that @wbuf->offs + @wbuf->size is aligned to
* @c->max_write_size. This way we make sure that after next
* write-buffer flush we are again at the optimal offset (aligned to
* @c->max_write_size).
*/
if (c->leb_size - wbuf->offs < c->max_write_size)
wbuf->size = c->leb_size - wbuf->offs;
else if (wbuf->offs & (c->max_write_size - 1))
wbuf->size = ALIGN(wbuf->offs, c->max_write_size) - wbuf->offs;
else
wbuf->size = c->max_write_size;
wbuf->avail = wbuf->size;
wbuf->used = 0;
wbuf->next_ino = 0;
spin_unlock(&wbuf->lock);
if (wbuf->sync_callback)
err = wbuf->sync_callback(c, wbuf->lnum,
c->leb_size - wbuf->offs, dirt);
return err;
}
/**
* ubifs_log_start_commit - start commit.
* @c: UBIFS file-system description object
* @ltail_lnum: return new log tail LEB number
*
* The commit operation starts with writing "commit start" node to the log and
* reference nodes for all journal heads which will define new journal after
* the commit has been finished. The commit start and reference nodes are
* written in one go to the nearest empty log LEB (hence, when commit is
* finished UBIFS may safely unmap all the previous log LEBs). This function
* returns zero in case of success and a negative error code in case of
* failure.
*/
int ubifs_log_start_commit(struct ubifs_info *c, int *ltail_lnum)
{
void *buf;
struct ubifs_cs_node *cs;
struct ubifs_ref_node *ref;
int err, i, max_len, len;
err = dbg_check_bud_bytes(c);
if (err)
return err;
max_len = UBIFS_CS_NODE_SZ + c->jhead_cnt * UBIFS_REF_NODE_SZ;
max_len = ALIGN(max_len, c->min_io_size);
buf = cs = kmalloc(max_len, GFP_NOFS);
if (!buf)
return -ENOMEM;
cs->ch.node_type = UBIFS_CS_NODE;
cs->cmt_no = cpu_to_le64(c->cmt_no);
ubifs_prepare_node(c, cs, UBIFS_CS_NODE_SZ, 0);
/*
* Note, we do not lock 'c->log_mutex' because this is the commit start
* phase and we are exclusively using the log. And we do not lock
* write-buffer because nobody can write to the file-system at this
* phase.
*/
len = UBIFS_CS_NODE_SZ;
for (i = 0; i < c->jhead_cnt; i++) {
int lnum = c->jheads[i].wbuf.lnum;
int offs = c->jheads[i].wbuf.offs;
if (lnum == -1 || offs == c->leb_size)
continue;
dbg_log("add ref to LEB %d:%d for jhead %s",
lnum, offs, dbg_jhead(i));
ref = buf + len;
ref->ch.node_type = UBIFS_REF_NODE;
ref->lnum = cpu_to_le32(lnum);
ref->offs = cpu_to_le32(offs);
ref->jhead = cpu_to_le32(i);
ubifs_prepare_node(c, ref, UBIFS_REF_NODE_SZ, 0);
len += UBIFS_REF_NODE_SZ;
}
ubifs_pad(c, buf + len, ALIGN(len, c->min_io_size) - len);
#ifdef CONFIG_UBIFS_FS_FULL_USE_LOG
/* Not Switch to next log LEB, programming next available page in the same log LEB continuously*/
/* if available page is in the end of the LEB, switch to next LEB*/
if(c->lhead_offs >= (c->leb_size - (c->min_io_size * 4)) )
{
int old_lnum = c->lhead_lnum;
int old_offs = c->lhead_offs;
c->lhead_lnum = ubifs_next_log_lnum(c, c->lhead_lnum);
c->lhead_offs = 0;
ubifs_msg("switch log LEB %d:%d to %d:%d\n", old_lnum, old_offs, c->lhead_lnum, c->lhead_offs);
}
#else
/* Switch to the next log LEB */
if (c->lhead_offs) {
int old_lnum = c->lhead_lnum;
int old_offs = c->lhead_offs;
c->lhead_lnum = ubifs_next_log_lnum(c, c->lhead_lnum);
c->lhead_offs = 0;
ubifs_msg("switch log LEB %d:%d to %d:%d\n", old_lnum, old_offs, c->lhead_lnum, c->lhead_offs);
}
#endif
if (c->lhead_offs == 0) {
/* Must ensure next LEB has been unmapped */
err = ubifs_leb_unmap(c, c->lhead_lnum);
if (err)
goto out;
}
len = ALIGN(len, c->min_io_size);
dbg_log("writing commit start at LEB %d:0, len %d", c->lhead_lnum, len);
err = ubifs_leb_write(c, c->lhead_lnum, cs, c->lhead_offs, len); //MTK, modify offset 0 -> c->lhead_offs
if (err)
goto out;
*ltail_lnum = c->lhead_lnum;
c->lhead_offs += len;
if (c->lhead_offs == c->leb_size) {
c->lhead_lnum = ubifs_next_log_lnum(c, c->lhead_lnum);
c->lhead_offs = 0;
}
remove_buds(c);
/*
* We have started the commit and now users may use the rest of the log
* for new writes.
*/
c->min_log_bytes = 0;
out:
kfree(buf);
return err;
}