/**
* nilfs_dat_move - change a block number
* @dat: DAT file inode
* @vblocknr: virtual block number
* @blocknr: block number
*
* Description: nilfs_dat_move() changes the block number associated with
* @vblocknr to @blocknr.
*
* Return Value: On success, 0 is returned. On error, one of the following
* negative error codes is returned.
*
* %-EIO - I/O error.
*
* %-ENOMEM - Insufficient amount of memory available.
*/
int nilfs_dat_move(struct inode *dat, __u64 vblocknr, sector_t blocknr)
{
struct buffer_head *entry_bh;
struct nilfs_dat_entry *entry;
void *kaddr;
int ret;
ret = nilfs_palloc_get_entry_block(dat, vblocknr, 0, &entry_bh);
if (ret < 0)
return ret;
/*
* The given disk block number (blocknr) is not yet written to
* the device at this point.
*
* To prevent nilfs_dat_translate() from returning the
* uncommitted block number, this makes a copy of the entry
* buffer and redirects nilfs_dat_translate() to the copy.
*/
if (!buffer_nilfs_redirected(entry_bh)) {
ret = nilfs_mdt_freeze_buffer(dat, entry_bh);
if (ret) {
brelse(entry_bh);
return ret;
}
}
kaddr = kmap_atomic(entry_bh->b_page);
entry = nilfs_palloc_block_get_entry(dat, vblocknr, entry_bh, kaddr);
if (unlikely(entry->de_blocknr == cpu_to_le64(0))) {
printk(KERN_CRIT "%s: vbn = %llu, [%llu, %llu)\n", __func__,
(unsigned long long)vblocknr,
(unsigned long long)le64_to_cpu(entry->de_start),
(unsigned long long)le64_to_cpu(entry->de_end));
kunmap_atomic(kaddr);
brelse(entry_bh);
return -EINVAL;
}
WARN_ON(blocknr == 0);
entry->de_blocknr = cpu_to_le64(blocknr);
kunmap_atomic(kaddr);
mark_buffer_dirty(entry_bh);
nilfs_mdt_mark_dirty(dat);
brelse(entry_bh);
return 0;
}
int nilfs_ifile_get_inode_block(struct inode *ifile, ino_t ino,
struct buffer_head **out_bh)
{
struct super_block *sb = ifile->i_sb;
int err;
if (unlikely(!NILFS_VALID_INODE(sb, ino))) {
nilfs_error(sb, "bad inode number: %lu", (unsigned long)ino);
return -EINVAL;
}
err = nilfs_palloc_get_entry_block(ifile, ino, 0, out_bh);
if (unlikely(err))
nilfs_msg(sb, KERN_WARNING, "error %d reading inode: ino=%lu",
err, (unsigned long)ino);
return err;
}
int nilfs_ifile_get_inode_block(struct inode *ifile, ino_t ino,
struct buffer_head **out_bh)
{
struct super_block *sb = ifile->i_sb;
int err;
if (unlikely(!NILFS_VALID_INODE(sb, ino))) {
nilfs_error(sb, __func__, "bad inode number: %lu",
(unsigned long) ino);
return -EINVAL;
}
err = nilfs_palloc_get_entry_block(ifile, ino, 0, out_bh);
if (unlikely(err))
nilfs_warning(sb, __func__, "unable to read inode: %lu",
(unsigned long) ino);
return err;
}
ssize_t nilfs_dat_get_vinfo(struct inode *dat, void *buf, unsigned visz,
size_t nvi)
{
struct buffer_head *entry_bh;
struct nilfs_dat_entry *entry;
struct nilfs_vinfo *vinfo = buf;
__u64 first, last;
void *kaddr;
unsigned long entries_per_block = NILFS_MDT(dat)->mi_entries_per_block;
int i, j, n, ret;
for (i = 0; i < nvi; i += n) {
ret = nilfs_palloc_get_entry_block(dat, vinfo->vi_vblocknr,
0, &entry_bh);
if (ret < 0)
return ret;
kaddr = kmap_atomic(entry_bh->b_page, KM_USER0);
/* last virtual block number in this block */
first = vinfo->vi_vblocknr;
do_div(first, entries_per_block);
first *= entries_per_block;
last = first + entries_per_block - 1;
for (j = i, n = 0;
j < nvi && vinfo->vi_vblocknr >= first &&
vinfo->vi_vblocknr <= last;
j++, n++, vinfo = (void *)vinfo + visz) {
entry = nilfs_palloc_block_get_entry(
dat, vinfo->vi_vblocknr, entry_bh, kaddr);
vinfo->vi_start = le64_to_cpu(entry->de_start);
vinfo->vi_end = le64_to_cpu(entry->de_end);
vinfo->vi_blocknr = le64_to_cpu(entry->de_blocknr);
}
kunmap_atomic(kaddr, KM_USER0);
brelse(entry_bh);
}
return nvi;
}
static int nilfs_dat_prepare_entry(struct inode *dat,
struct nilfs_palloc_req *req, int create)
{
return nilfs_palloc_get_entry_block(dat, req->pr_entry_nr,
create, &req->pr_entry_bh);
}
