/*
* __wt_block_checkpoint_unload --
* Unload a checkpoint.
*/
int
__wt_block_checkpoint_unload(
WT_SESSION_IMPL *session, WT_BLOCK *block, bool checkpoint)
{
WT_DECL_RET;
/* Verify cleanup. */
if (block->verify)
WT_TRET(__wt_verify_ckpt_unload(session, block));
/*
* If it's the live system, truncate to discard any extended blocks and
* discard the active extent lists. Hold the lock even though we're
* unloading the live checkpoint, there could be readers active in other
* checkpoints.
*/
if (!checkpoint) {
WT_TRET(__wt_block_truncate(session, block, block->size));
__wt_spin_lock(session, &block->live_lock);
__wt_block_ckpt_destroy(session, &block->live);
#ifdef HAVE_DIAGNOSTIC
block->live_open = false;
#endif
__wt_spin_unlock(session, &block->live_lock);
}
return (ret);
}
/*
* __wt_block_checkpoint_unload --
* Unload a checkpoint.
*/
int
__wt_block_checkpoint_unload(
WT_SESSION_IMPL *session, WT_BLOCK *block, bool checkpoint)
{
WT_DECL_RET;
/* Verify cleanup. */
if (block->verify)
WT_TRET(__wt_verify_ckpt_unload(session, block));
/*
* If it's the live system, truncate to discard any extended blocks and
* discard the active extent lists. Hold the lock even though we're
* unloading the live checkpoint, there could be readers active in
* other checkpoints.
*/
if (!checkpoint) {
/*
* The truncate might fail if there's a file mapping (if there's
* an open checkpoint on the file), that's OK.
*/
WT_TRET_BUSY_OK(
__wt_block_truncate(session, block->fh, block->fh->size));
__wt_spin_lock(session, &block->live_lock);
__wt_block_ckpt_destroy(session, &block->live);
__wt_spin_unlock(session, &block->live_lock);
}
return (ret);
}
/*
* __wt_block_salvage_start --
* Start a file salvage.
*/
int
__wt_block_salvage_start(WT_SESSION_IMPL *session, WT_BLOCK *block)
{
wt_off_t len;
uint32_t allocsize;
allocsize = block->allocsize;
/* Reset the description information in the first block. */
WT_RET(__wt_desc_write(session, block->fh, allocsize));
/*
* Salvage creates a new checkpoint when it's finished, set up for
* rolling an empty file forward.
*/
WT_RET(__wt_block_ckpt_init(session, &block->live, "live"));
/*
* Truncate the file to an allocation-size multiple of blocks (bytes
* trailing the last block must be garbage, by definition).
*/
len = allocsize;
if (block->size > allocsize)
len = (block->size / allocsize) * allocsize;
WT_RET(__wt_block_truncate(session, block, len));
/*
* The file's first allocation-sized block is description information,
* skip it when reading through the file.
*/
block->slvg_off = allocsize;
/*
* The only checkpoint extent we care about is the allocation list.
* Start with the entire file on the allocation list, we'll "free"
* any blocks we don't want as we process the file.
*/
WT_RET(__wt_block_insert_ext(
session, block, &block->live.alloc, allocsize, len - allocsize));
/* Salvage performs a checkpoint but doesn't start or resolve it. */
WT_ASSERT(session, block->ckpt_state == WT_CKPT_NONE);
block->ckpt_state = WT_CKPT_SALVAGE;
return (0);
}
/*
* __wt_block_checkpoint_load --
* Load a checkpoint.
*/
int
__wt_block_checkpoint_load(WT_SESSION_IMPL *session, WT_BLOCK *block,
const uint8_t *addr, size_t addr_size,
uint8_t *root_addr, size_t *root_addr_sizep, bool checkpoint)
{
WT_BLOCK_CKPT *ci, _ci;
WT_DECL_ITEM(tmp);
WT_DECL_RET;
uint8_t *endp;
ci = NULL;
/*
* Sometimes we don't find a root page (we weren't given a checkpoint,
* or the checkpoint was empty). In that case we return an empty root
* address, set that up now.
*/
*root_addr_sizep = 0;
#ifdef HAVE_VERBOSE
if (WT_VERBOSE_ISSET(session, WT_VERB_CHECKPOINT)) {
if (addr != NULL) {
WT_ERR(__wt_scr_alloc(session, 0, &tmp));
WT_ERR(__ckpt_string(session, block, addr, tmp));
}
__wt_verbose(session, WT_VERB_CHECKPOINT,
"%s: load-checkpoint: %s", block->name,
addr == NULL ? "[Empty]" : (const char *)tmp->data);
}
#endif
/*
* There's a single checkpoint in the file that can be written, all of
* the others are read-only. We use the same initialization calls for
* readonly checkpoints, but the information doesn't persist.
*/
if (checkpoint) {
ci = &_ci;
WT_ERR(__wt_block_ckpt_init(session, ci, "checkpoint"));
} else {
/*
* We depend on the btree level for locking: things will go bad
* fast if we open the live system in two handles, or salvage,
* truncate or verify the live/running file.
*/
#ifdef HAVE_DIAGNOSTIC
__wt_spin_lock(session, &block->live_lock);
WT_ASSERT(session, block->live_open == false);
block->live_open = true;
__wt_spin_unlock(session, &block->live_lock);
#endif
ci = &block->live;
WT_ERR(__wt_block_ckpt_init(session, ci, "live"));
}
/*
* If the checkpoint has an on-disk root page, load it. Otherwise, size
* the file past the description information.
*/
if (addr == NULL || addr_size == 0)
ci->file_size = block->allocsize;
else {
/* Crack the checkpoint cookie. */
WT_ERR(__wt_block_buffer_to_ckpt(session, block, addr, ci));
/* Verify sets up next. */
if (block->verify)
WT_ERR(__wt_verify_ckpt_load(session, block, ci));
/* Read any root page. */
if (ci->root_offset != WT_BLOCK_INVALID_OFFSET) {
endp = root_addr;
WT_ERR(__wt_block_addr_to_buffer(block, &endp,
ci->root_offset, ci->root_size, ci->root_checksum));
*root_addr_sizep = WT_PTRDIFF(endp, root_addr);
}
/*
* Rolling a checkpoint forward requires the avail list, the
* blocks from which we can allocate.
*/
if (!checkpoint)
WT_ERR(__wt_block_extlist_read_avail(
session, block, &ci->avail, ci->file_size));
}
/*
* If the checkpoint can be written, that means anything written after
* the checkpoint is no longer interesting, truncate the file. Don't
* bother checking the avail list for a block at the end of the file,
* that was done when the checkpoint was first written (re-writing the
* checkpoint might possibly make it relevant here, but it's unlikely
* enough I don't bother).
*/
if (!checkpoint)
WT_ERR(__wt_block_truncate(session, block, ci->file_size));
if (0) {
err: /*
* Don't call checkpoint-unload: unload does real work including
* file truncation. If we fail early enough that the checkpoint
* information isn't correct, bad things would happen. The only
* allocated memory was in the service of verify, clean that up.
*/
if (block->verify)
WT_TRET(__wt_verify_ckpt_unload(session, block));
}
/* Checkpoints don't need the original information, discard it. */
if (checkpoint && ci != NULL)
__wt_block_ckpt_destroy(session, ci);
__wt_scr_free(session, &tmp);
return (ret);
}