int blockio(int rw, struct sb *sb, struct buffer_head *buffer, block_t block)
{
trace("%s: buffer %p, block %Lx", rw ? "write" : "read",
buffer, block);
return devio(rw, sb_dev(sb), block << sb->blockbits, bufdata(buffer),
sb->blocksize);
}
/* Clear first and last block to get rid of other magic */
static int clear_other_magic(struct sb *sb)
{
struct {
loff_t loc;
unsigned len;
} area[] = {
{ 0, SB_LOC },
{ (sb->volblocks - 1) << sb->blockbits, sb->blocksize },
};
void *data;
unsigned maxlen = 0;
int err;
for (int i = 0; i < ARRAY_SIZE(area); i++)
maxlen = max(maxlen, area[i].len);
data = malloc(maxlen);
if (!data)
return -ENOMEM;
memset(data, 0, maxlen);
for (int i = 0; i < ARRAY_SIZE(area); i++) {
err = devio(WRITE, sb->dev, area[i].loc, data, area[i].len);
if (err)
break;
}
free(data);
return err;
}
static int clear_other_magic(struct sb *sb)
{
int err;
/* Clear first and last block to get rid of other magic */
for (int i = 0; i <= 1; i++) {
loff_t loc = (loff_t[2]){ 0, (sb->volblocks - 1) << sb->blockbits }[i];
unsigned len = (loff_t[2]){ SB_LOC, sb->blocksize }[i];
char data[len];
memset(data, 0, len);
err = devio(WRITE, sb->dev, loc, data, len);
if (err)
break;
}
return err;
}
int save_sb(struct sb *sb)
{
struct disksuper *super = &sb->super;
super->blockbits = cpu_to_be16(sb->blockbits);
super->volblocks = cpu_to_be64(sb->volblocks);
/* Probably does not belong here (maybe metablock) */
super->iroot = cpu_to_be64(pack_root(&itable_btree(sb)->root));
super->oroot = cpu_to_be64(pack_root(&otable_btree(sb)->root));
super->nextalloc = cpu_to_be64(sb->nextalloc);
super->atomdictsize = cpu_to_be64(sb->atomdictsize);
super->freeatom = cpu_to_be32(sb->freeatom);
super->atomgen = cpu_to_be32(sb->atomgen);
/* logchain and logcount are written to super directly */
return devio(WRITE, sb_dev(sb), SB_LOC, super, SB_LEN);
}
/* Load on-disk super block, and call setup_sb() with it */
int load_sb(struct sb *sb)
{
struct disksuper *super = &sb->super;
int err;
/* At least initialize sb, even if load is failed */
init_sb(sb);
err = devio(READ, sb_dev(sb), SB_LOC, super, SB_LEN);
if (err)
return err;
if (memcmp(super->magic, TUX3_MAGIC, sizeof(super->magic)))
return -EINVAL;
__setup_sb(sb, super);
return 0;
}
