/*
* lock allocators, and reserving appropriate number of bits for
* meta blocks and data clusters.
*
* in some cases, we don't need to reserve clusters, just let data_ac
* be NULL.
*/
static int ocfs2_lock_allocators_move_extents(struct inode *inode,
struct ocfs2_extent_tree *et,
u32 clusters_to_move,
u32 extents_to_split,
struct ocfs2_alloc_context **meta_ac,
struct ocfs2_alloc_context **data_ac,
int extra_blocks,
int *credits)
{
int ret, num_free_extents;
unsigned int max_recs_needed = 2 * extents_to_split + clusters_to_move;
struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
num_free_extents = ocfs2_num_free_extents(osb, et);
if (num_free_extents < 0) {
ret = num_free_extents;
mlog_errno(ret);
goto out;
}
if (!num_free_extents ||
(ocfs2_sparse_alloc(osb) && num_free_extents < max_recs_needed))
extra_blocks += ocfs2_extend_meta_needed(et->et_root_el);
ret = ocfs2_reserve_new_metadata_blocks(osb, extra_blocks, meta_ac);
if (ret) {
mlog_errno(ret);
goto out;
}
if (data_ac) {
ret = ocfs2_reserve_clusters(osb, clusters_to_move, data_ac);
if (ret) {
mlog_errno(ret);
goto out;
}
}
*credits += ocfs2_calc_extend_credits(osb->sb, et->et_root_el,
clusters_to_move + 2);
mlog(0, "reserve metadata_blocks: %d, data_clusters: %u, credits: %d\n",
extra_blocks, clusters_to_move, *credits);
out:
if (ret) {
if (*meta_ac) {
ocfs2_free_alloc_context(*meta_ac);
*meta_ac = NULL;
}
}
return ret;
}
/*
* For a given allocation, determine which allocators will need to be
* accessed, and lock them, reserving the appropriate number of bits.
*
* Called from ocfs2_extend_allocation() for file systems which don't
* support holes, and from ocfs2_write() for file systems which
* understand sparse inodes.
*/
int ocfs2_lock_allocators(struct inode *inode, struct ocfs2_dinode *di,
u32 clusters_to_add,
struct ocfs2_alloc_context **data_ac,
struct ocfs2_alloc_context **meta_ac)
{
int ret, num_free_extents;
struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
*meta_ac = NULL;
*data_ac = NULL;
mlog(0, "extend inode %llu, i_size = %lld, di->i_clusters = %u, "
"clusters_to_add = %u\n",
(unsigned long long)OCFS2_I(inode)->ip_blkno, i_size_read(inode),
le32_to_cpu(di->i_clusters), clusters_to_add);
num_free_extents = ocfs2_num_free_extents(osb, inode, di);
if (num_free_extents < 0) {
ret = num_free_extents;
mlog_errno(ret);
goto out;
}
/*
* Sparse allocation file systems need to be more conservative
* with reserving room for expansion - the actual allocation
* happens while we've got a journal handle open so re-taking
* a cluster lock (because we ran out of room for another
* extent) will violate ordering rules.
*
* Most of the time we'll only be seeing this 1 cluster at a time
* anyway.
*/
if (!num_free_extents ||
(ocfs2_sparse_alloc(osb) && num_free_extents < clusters_to_add)) {
ret = ocfs2_reserve_new_metadata(osb, di, meta_ac);
if (ret < 0) {
if (ret != -ENOSPC)
mlog_errno(ret);
goto out;
}
}
ret = ocfs2_reserve_clusters(osb, clusters_to_add, data_ac);
if (ret < 0) {
if (ret != -ENOSPC)
mlog_errno(ret);
goto out;
}
out:
if (ret) {
if (*meta_ac) {
ocfs2_free_alloc_context(*meta_ac);
*meta_ac = NULL;
}
/*
* We cannot have an error and a non null *data_ac.
*/
}
return ret;
}
/*
* extend allocation only here.
* we'll update all the disk stuff, and oip->alloc_size
*
* expect stuff to be locked, a transaction started and enough data /
* metadata reservations in the contexts.
*
* Will return -EAGAIN, and a reason if a restart is needed.
* If passed in, *reason will always be set, even in error.
*/
int ocfs2_do_extend_allocation(struct ocfs2_super *osb,
struct inode *inode,
u32 *logical_offset,
u32 clusters_to_add,
struct buffer_head *fe_bh,
handle_t *handle,
struct ocfs2_alloc_context *data_ac,
struct ocfs2_alloc_context *meta_ac,
enum ocfs2_alloc_restarted *reason_ret)
{
int status = 0;
int free_extents;
struct ocfs2_dinode *fe = (struct ocfs2_dinode *) fe_bh->b_data;
enum ocfs2_alloc_restarted reason = RESTART_NONE;
u32 bit_off, num_bits;
u64 block;
BUG_ON(!clusters_to_add);
free_extents = ocfs2_num_free_extents(osb, inode, fe);
if (free_extents < 0) {
status = free_extents;
mlog_errno(status);
goto leave;
}
/* there are two cases which could cause us to EAGAIN in the
* we-need-more-metadata case:
* 1) we haven't reserved *any*
* 2) we are so fragmented, we've needed to add metadata too
* many times. */
if (!free_extents && !meta_ac) {
mlog(0, "we haven't reserved any metadata!\n");
status = -EAGAIN;
reason = RESTART_META;
goto leave;
} else if ((!free_extents)
&& (ocfs2_alloc_context_bits_left(meta_ac)
< ocfs2_extend_meta_needed(fe))) {
mlog(0, "filesystem is really fragmented...\n");
status = -EAGAIN;
reason = RESTART_META;
goto leave;
}
status = ocfs2_claim_clusters(osb, handle, data_ac, 1,
&bit_off, &num_bits);
if (status < 0) {
if (status != -ENOSPC)
mlog_errno(status);
goto leave;
}
BUG_ON(num_bits > clusters_to_add);
/* reserve our write early -- insert_extent may update the inode */
status = ocfs2_journal_access(handle, inode, fe_bh,
OCFS2_JOURNAL_ACCESS_WRITE);
if (status < 0) {
mlog_errno(status);
goto leave;
}
block = ocfs2_clusters_to_blocks(osb->sb, bit_off);
mlog(0, "Allocating %u clusters at block %u for inode %llu\n",
num_bits, bit_off, (unsigned long long)OCFS2_I(inode)->ip_blkno);
status = ocfs2_insert_extent(osb, handle, inode, fe_bh,
*logical_offset, block, num_bits,
meta_ac);
if (status < 0) {
mlog_errno(status);
goto leave;
}
status = ocfs2_journal_dirty(handle, fe_bh);
if (status < 0) {
mlog_errno(status);
goto leave;
}
clusters_to_add -= num_bits;
*logical_offset += num_bits;
if (clusters_to_add) {
mlog(0, "need to alloc once more, clusters = %u, wanted = "
"%u\n", fe->i_clusters, clusters_to_add);
status = -EAGAIN;
reason = RESTART_TRANS;
}
leave:
mlog_exit(status);
if (reason_ret)
*reason_ret = reason;
return status;
}
