static void logfs_kill_sb(struct super_block *sb)
{
struct logfs_super *super = logfs_super(sb);
log_super("LogFS: Start unmounting\n");
/* Alias entries slow down mount, so evict as many as possible */
sync_filesystem(sb);
logfs_write_anchor(sb);
free_areas(sb);
/*
* From this point on alias entries are simply dropped - and any
* writes to the object store are considered bugs.
*/
log_super("LogFS: Now in shutdown\n");
generic_shutdown_super(sb);
super->s_flags |= LOGFS_SB_FLAG_SHUTDOWN;
BUG_ON(super->s_dirty_used_bytes || super->s_dirty_free_bytes);
logfs_cleanup_gc(sb);
logfs_cleanup_journal(sb);
logfs_cleanup_areas(sb);
logfs_cleanup_rw(sb);
if (super->s_erase_page)
__free_page(super->s_erase_page);
super->s_devops->put_device(super);
logfs_mempool_destroy(super->s_btree_pool);
logfs_mempool_destroy(super->s_alias_pool);
kfree(super);
log_super("LogFS: Finished unmounting\n");
}
static struct dentry *logfs_get_sb_device(struct logfs_super *super,
struct file_system_type *type, int flags)
{
struct super_block *sb;
int err = -ENOMEM;
static int mount_count;
log_super("LogFS: Start mount %x\n", mount_count++);
err = -EINVAL;
sb = sget(type, logfs_sb_test, logfs_sb_set, flags | MS_NOATIME, super);
/*
if (IS_ERR(sb)) {
super->s_devops->put_device(super);
kfree(super);
return ERR_CAST(sb);
}
if (sb->s_root) {
// Device is already in use
super->s_devops->put_device(super);
kfree(super);
return dget(sb->s_root);
}
*/
/*
* sb->s_maxbytes is limited to 8TB. On 32bit systems, the page cache
* only covers 16TB and the upper 8TB are used for indirect blocks.
* On 64bit system we could bump up the limit, but that would make
* the filesystem incompatible with 32bit systems.
*/
sb->s_maxbytes = (1ull << 43) - 1;
sb->s_max_links = LOGFS_LINK_MAX;
sb->s_op = &logfs_super_operations;
err = logfs_read_sb(sb, sb->s_flags & MS_RDONLY);
if (err)
//goto err1;
return ERR_PTR(err);
sb->s_flags |= MS_ACTIVE;
err = logfs_get_sb_final(sb);
if (err) {
//deactivate_locked_super(sb);
return ERR_PTR(err);
}
return dget(sb->s_root);
/*
err1:
// no ->s_root, no ->put_super()
iput(super->s_master_inode);
iput(super->s_segfile_inode);
iput(super->s_mapping_inode);
deactivate_locked_super(sb);
return ERR_PTR(err);
*/
}
static int logfs_get_sb_final(struct super_block *sb)
{
struct logfs_super *super = logfs_super(sb);
struct inode *rootdir;
int err;
/* root dir */
rootdir = logfs_iget(sb, LOGFS_INO_ROOT);
if (IS_ERR(rootdir))
//goto fail;
return -EIO;
sb->s_root = d_make_root(rootdir);
if (!sb->s_root)
//goto fail;
return -EIO;
// at that point we know that ->put_super() will be called
super->s_erase_page = alloc_pages(GFP_KERNEL, 0);
if (!super->s_erase_page)
return -ENOMEM;
memset(page_address(super->s_erase_page), 0xFF, PAGE_SIZE);
/*
// FIXME: check for read-only mounts
err = logfs_make_writeable(sb);
if (err) {
__free_page(super->s_erase_page);
return err;
}
*/
log_super("LogFS: Finished mounting\n");
return 0;
/*
fail:
iput(super->s_master_inode);
iput(super->s_segfile_inode);
iput(super->s_mapping_inode);
return -EIO;
*/
}
static int log_writes_kthread(void *arg)
{
struct log_writes_c *lc = (struct log_writes_c *)arg;
sector_t sector = 0;
while (!kthread_should_stop()) {
bool super = false;
bool logging_enabled;
struct pending_block *block = NULL;
int ret;
spin_lock_irq(&lc->blocks_lock);
if (!list_empty(&lc->logging_blocks)) {
block = list_first_entry(&lc->logging_blocks,
struct pending_block, list);
list_del_init(&block->list);
if (!lc->logging_enabled)
goto next;
sector = lc->next_sector;
if (block->flags & LOG_DISCARD_FLAG)
lc->next_sector++;
else
lc->next_sector += block->nr_sectors + 1;
/*
* Apparently the size of the device may not be known
* right away, so handle this properly.
*/
if (!lc->end_sector)
lc->end_sector = logdev_last_sector(lc);
if (lc->end_sector &&
lc->next_sector >= lc->end_sector) {
DMERR("Ran out of space on the logdev");
lc->logging_enabled = false;
goto next;
}
lc->logged_entries++;
atomic_inc(&lc->io_blocks);
super = (block->flags & (LOG_FUA_FLAG | LOG_MARK_FLAG));
if (super)
atomic_inc(&lc->io_blocks);
}
next:
logging_enabled = lc->logging_enabled;
spin_unlock_irq(&lc->blocks_lock);
if (block) {
if (logging_enabled) {
ret = log_one_block(lc, block, sector);
if (!ret && super)
ret = log_super(lc);
if (ret) {
spin_lock_irq(&lc->blocks_lock);
lc->logging_enabled = false;
spin_unlock_irq(&lc->blocks_lock);
}
} else
free_pending_block(lc, block);
continue;
}
if (!try_to_freeze()) {
set_current_state(TASK_INTERRUPTIBLE);
if (!kthread_should_stop() &&
!atomic_read(&lc->pending_blocks))
schedule();
__set_current_state(TASK_RUNNING);
}
}
