* block will be so we can update his h_next_leaf_blk field, as well
* as the dinodes i_last_eb_blk */
static int ocfs2_find_new_last_ext_blk(struct inode *inode,
- u32 new_i_clusters,
+ unsigned int clusters_to_del,
struct ocfs2_path *path,
struct buffer_head **new_last_eb)
{
- int ret = 0;
+ int next_free, ret = 0;
u32 cpos;
+ struct ocfs2_extent_rec *rec;
struct ocfs2_extent_block *eb;
struct ocfs2_extent_list *el;
struct buffer_head *bh = NULL;
/* trunc to zero special case - this makes tree_depth = 0
* regardless of what it is. */
- if (!new_i_clusters)
+ if (OCFS2_I(inode)->ip_clusters == clusters_to_del)
goto out;
el = path_leaf_el(path);
BUG_ON(!el->l_next_free_rec);
- /* Make sure that this guy will actually be empty after we
- * clear away the data. */
+ /*
+ * Make sure that this extent list will actually be empty
+ * after we clear away the data. We can shortcut out if
+ * there's more than one non-empty extent in the
+ * list. Otherwise, a check of the remaining extent is
+ * necessary.
+ */
+ next_free = le16_to_cpu(el->l_next_free_rec);
+ rec = NULL;
if (ocfs2_is_empty_extent(&el->l_recs[0])) {
- if (le16_to_cpu(el->l_next_free_rec) > 1 &&
- le32_to_cpu(el->l_recs[1].e_cpos) < new_i_clusters)
+ if (next_free > 2)
goto out;
- } else if (le32_to_cpu(el->l_recs[0].e_cpos) < new_i_clusters)
- goto out;
+
+ /* We may have a valid extent in index 1, check it. */
+ if (next_free == 2)
+ rec = &el->l_recs[1];
+
+ /*
+ * Fall through - no more nonempty extents, so we want
+ * to delete this leaf.
+ */
+ } else {
+ if (next_free > 1)
+ goto out;
+
+ rec = &el->l_recs[0];
+ }
+
+ if (rec) {
+ /*
+ * Check it we'll only be trimming off the end of this
+ * cluster.
+ */
+ if (le16_to_cpu(rec->e_clusters) > clusters_to_del)
+ goto out;
+ }
ret = ocfs2_find_cpos_for_left_leaf(inode->i_sb, path, &cpos);
if (ret) {
return ret;
}
+/*
+ * Trim some clusters off the rightmost edge of a tree. Only called
+ * during truncate.
+ *
+ * The caller needs to:
+ * - start journaling of each path component.
+ * - compute and fully set up any new last ext block
+ */
+static int ocfs2_trim_tree(struct inode *inode, struct ocfs2_path *path,
+ handle_t *handle, struct ocfs2_truncate_context *tc,
+ u32 clusters_to_del, u64 *delete_start)
+{
+ int ret, i, index = path->p_tree_depth;
+ u32 new_edge = 0;
+ u64 deleted_eb = 0;
+ struct buffer_head *bh;
+ struct ocfs2_extent_list *el;
+ struct ocfs2_extent_rec *rec;
+
+ *delete_start = 0;
+
+ while (index >= 0) {
+ bh = path->p_node[index].bh;
+ el = path->p_node[index].el;
+
+ mlog(0, "traveling tree (index = %d, block = %llu)\n",
+ index, (unsigned long long)bh->b_blocknr);
+
+ BUG_ON(le16_to_cpu(el->l_next_free_rec) == 0);
+
+ if (index !=
+ (path->p_tree_depth - le16_to_cpu(el->l_tree_depth))) {
+ ocfs2_error(inode->i_sb,
+ "Inode %lu has invalid ext. block %llu",
+ inode->i_ino,
+ (unsigned long long)bh->b_blocknr);
+ ret = -EROFS;
+ goto out;
+ }
+
+find_tail_record:
+ i = le16_to_cpu(el->l_next_free_rec) - 1;
+ rec = &el->l_recs[i];
+
+ mlog(0, "Extent list before: record %d: (%u, %u, %llu), "
+ "next = %u\n", i, le32_to_cpu(rec->e_cpos),
+ le32_to_cpu(rec->e_clusters),
+ (unsigned long long)le64_to_cpu(rec->e_blkno),
+ le16_to_cpu(el->l_next_free_rec));
+
+ BUG_ON(le32_to_cpu(rec->e_clusters) < clusters_to_del);
+
+ if (le16_to_cpu(el->l_tree_depth) == 0) {
+ /*
+ * If the leaf block contains a single empty
+ * extent and no records, we can just remove
+ * the block.
+ */
+ if (i == 0 && ocfs2_is_empty_extent(rec)) {
+ memset(rec, 0,
+ sizeof(struct ocfs2_extent_rec));
+ el->l_next_free_rec = cpu_to_le16(0);
+
+ goto delete;
+ }
+
+ /*
+ * Remove any empty extents by shifting things
+ * left. That should make life much easier on
+ * the code below. This condition is rare
+ * enough that we shouldn't see a performance
+ * hit.
+ */
+ if (ocfs2_is_empty_extent(&el->l_recs[0])) {
+ le16_add_cpu(&el->l_next_free_rec, -1);
+
+ for(i = 0;
+ i < le16_to_cpu(el->l_next_free_rec); i++)
+ el->l_recs[i] = el->l_recs[i + 1];
+
+ memset(&el->l_recs[i], 0,
+ sizeof(struct ocfs2_extent_rec));
+
+ /*
+ * We've modified our extent list. The
+ * simplest way to handle this change
+ * is to being the search from the
+ * start again.
+ */
+ goto find_tail_record;
+ }
+
+ le32_add_cpu(&rec->e_clusters, -clusters_to_del);
+
+ /*
+ * We'll use "new_edge" on our way back up the
+ * tree to know what our rightmost cpos is.
+ */
+ new_edge = le32_to_cpu(rec->e_clusters);
+ new_edge += le32_to_cpu(rec->e_cpos);
+
+ /*
+ * The caller will use this to delete data blocks.
+ */
+ *delete_start = le64_to_cpu(rec->e_blkno)
+ + ocfs2_clusters_to_blocks(inode->i_sb,
+ le32_to_cpu(rec->e_clusters));
+
+ /*
+ * If it's now empty, remove this record.
+ */
+ if (le32_to_cpu(rec->e_clusters) == 0) {
+ memset(rec, 0,
+ sizeof(struct ocfs2_extent_rec));
+ le16_add_cpu(&el->l_next_free_rec, -1);
+ }
+ } else {
+ if (le64_to_cpu(rec->e_blkno) == deleted_eb) {
+ memset(rec, 0,
+ sizeof(struct ocfs2_extent_rec));
+ le16_add_cpu(&el->l_next_free_rec, -1);
+
+ goto delete;
+ }
+
+ /* Can this actually happen? */
+ if (le16_to_cpu(el->l_next_free_rec) == 0)
+ goto delete;
+
+ /*
+ * We never actually deleted any clusters
+ * because our leaf was empty. There's no
+ * reason to adjust the rightmost edge then.
+ */
+ if (new_edge == 0)
+ goto delete;
+
+ rec->e_clusters = cpu_to_le32(new_edge);
+ le32_add_cpu(&rec->e_clusters,
+ -le32_to_cpu(rec->e_cpos));
+
+ /*
+ * A deleted child record should have been
+ * caught above.
+ */
+ BUG_ON(le32_to_cpu(rec->e_clusters) == 0);
+ }
+
+delete:
+ ret = ocfs2_journal_dirty(handle, bh);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ mlog(0, "extent list container %llu, after: record %d: "
+ "(%u, %u, %llu), next = %u.\n",
+ (unsigned long long)bh->b_blocknr, i,
+ le32_to_cpu(rec->e_cpos), le32_to_cpu(rec->e_clusters),
+ (unsigned long long)le64_to_cpu(rec->e_blkno),
+ le16_to_cpu(el->l_next_free_rec));
+
+ /*
+ * We must be careful to only attempt delete of an
+ * extent block (and not the root inode block).
+ */
+ if (index > 0 && le16_to_cpu(el->l_next_free_rec) == 0) {
+ struct ocfs2_extent_block *eb =
+ (struct ocfs2_extent_block *)bh->b_data;
+
+ /*
+ * Save this for use when processing the
+ * parent block.
+ */
+ deleted_eb = le64_to_cpu(eb->h_blkno);
+
+ mlog(0, "deleting this extent block.\n");
+
+ ocfs2_remove_from_cache(inode, bh);
+
+ BUG_ON(le32_to_cpu(el->l_recs[0].e_clusters));
+ BUG_ON(le32_to_cpu(el->l_recs[0].e_cpos));
+ BUG_ON(le64_to_cpu(el->l_recs[0].e_blkno));
+
+ if (le16_to_cpu(eb->h_suballoc_slot) == 0) {
+ /*
+ * This code only understands how to
+ * lock the suballocator in slot 0,
+ * which is fine because allocation is
+ * only ever done out of that
+ * suballocator too. A future version
+ * might change that however, so avoid
+ * a free if we don't know how to
+ * handle it. This way an fs incompat
+ * bit will not be necessary.
+ */
+ ret = ocfs2_free_extent_block(handle,
+ tc->tc_ext_alloc_inode,
+ tc->tc_ext_alloc_bh,
+ eb);
+
+ /* An error here is not fatal. */
+ if (ret < 0)
+ mlog_errno(ret);
+ }
+ } else {
+ deleted_eb = 0;
+ }
+
+ index--;
+ }
+
+ ret = 0;
+out:
+ return ret;
+}
+
static int ocfs2_do_truncate(struct ocfs2_super *osb,
unsigned int clusters_to_del,
struct inode *inode,
struct ocfs2_truncate_context *tc,
struct ocfs2_path *path)
{
- int status, i, index;
+ int status;
struct ocfs2_dinode *fe;
- struct ocfs2_extent_block *eb;
struct ocfs2_extent_block *last_eb = NULL;
struct ocfs2_extent_list *el;
- struct buffer_head *eb_bh = NULL;
struct buffer_head *last_eb_bh = NULL;
u64 delete_blk = 0;
fe = (struct ocfs2_dinode *) fe_bh->b_data;
- status = ocfs2_find_new_last_ext_blk(inode,
- le32_to_cpu(fe->i_clusters) -
- clusters_to_del,
+ status = ocfs2_find_new_last_ext_blk(inode, clusters_to_del,
path, &last_eb_bh);
if (status < 0) {
mlog_errno(status);
* Each component will be touched, so we might as well journal
* here to avoid having to handle errors later.
*/
- for (i = 0; i < path_num_items(path); i++) {
- status = ocfs2_journal_access(handle, inode,
- path->p_node[i].bh,
- OCFS2_JOURNAL_ACCESS_WRITE);
- if (status < 0) {
- mlog_errno(status);
- goto bail;
- }
+ status = ocfs2_journal_access_path(inode, handle, path);
+ if (status < 0) {
+ mlog_errno(status);
+ goto bail;
}
if (last_eb_bh) {
ocfs2_error(inode->i_sb,
"Inode %lu has an empty extent record, depth %u\n",
inode->i_ino, le16_to_cpu(el->l_tree_depth));
+ status = -EROFS;
goto bail;
}
spin_unlock(&OCFS2_I(inode)->ip_lock);
le32_add_cpu(&fe->i_clusters, -clusters_to_del);
- i = le16_to_cpu(el->l_next_free_rec) - 1;
-
- BUG_ON(le32_to_cpu(el->l_recs[i].e_clusters) < clusters_to_del);
- le32_add_cpu(&el->l_recs[i].e_clusters, -clusters_to_del);
- /* tree depth zero, we can just delete the clusters, otherwise
- * we need to record the offset of the next level extent block
- * as we may overwrite it. */
- if (!el->l_tree_depth) {
- delete_blk = le64_to_cpu(el->l_recs[i].e_blkno)
- + ocfs2_clusters_to_blocks(osb->sb,
- le32_to_cpu(el->l_recs[i].e_clusters));
-
- if (!el->l_recs[i].e_clusters) {
- /* if we deleted the whole extent record, then clear
- * out the other fields and update the extent
- * list.
- */
- el->l_recs[i].e_cpos = 0;
- el->l_recs[i].e_blkno = 0;
- BUG_ON(!el->l_next_free_rec);
- le16_add_cpu(&el->l_next_free_rec, -1);
-
- /*
- * The leftmost record might be an empty extent -
- * delete it here too.
- */
- if (i == 1 && ocfs2_is_empty_extent(&el->l_recs[0])) {
- el->l_recs[0].e_cpos = 0;
- el->l_recs[0].e_blkno = 0;
- el->l_next_free_rec = 0;
- }
- }
+ status = ocfs2_trim_tree(inode, path, handle, tc,
+ clusters_to_del, &delete_blk);
+ if (status) {
+ mlog_errno(status);
+ goto bail;
}
if (le32_to_cpu(fe->i_clusters) == 0) {
}
}
- index = 1;
- /* if our tree depth > 0, update all the tree blocks below us. */
- while (index <= path->p_tree_depth) {
- eb_bh = path->p_node[index].bh;
- eb = (struct ocfs2_extent_block *)eb_bh->b_data;
- el = path->p_node[index].el;
-
- mlog(0, "traveling tree (index = %d, extent block: %llu)\n",
- index, (unsigned long long)eb_bh->b_blocknr);
-
- BUG_ON(le16_to_cpu(el->l_next_free_rec) == 0);
- if (index !=
- (path->p_tree_depth - le16_to_cpu(el->l_tree_depth))) {
- ocfs2_error(inode->i_sb,
- "Inode %lu has invalid ext. block %llu\n",
- inode->i_ino,
- (unsigned long long)eb_bh->b_blocknr);
- goto bail;
- }
-
- i = le16_to_cpu(el->l_next_free_rec) - 1;
-
- mlog(0, "extent block %llu, before: record %d: "
- "(%u, %u, %llu), next = %u\n",
- (unsigned long long)le64_to_cpu(eb->h_blkno), i,
- le32_to_cpu(el->l_recs[i].e_cpos),
- le32_to_cpu(el->l_recs[i].e_clusters),
- (unsigned long long)le64_to_cpu(el->l_recs[i].e_blkno),
- le16_to_cpu(el->l_next_free_rec));
-
- BUG_ON(le32_to_cpu(el->l_recs[i].e_clusters) < clusters_to_del);
- le32_add_cpu(&el->l_recs[i].e_clusters, -clusters_to_del);
-
- /* bottom-most block requires us to delete data.*/
- if (!el->l_tree_depth)
- delete_blk = le64_to_cpu(el->l_recs[i].e_blkno)
- + ocfs2_clusters_to_blocks(osb->sb,
- le32_to_cpu(el->l_recs[i].e_clusters));
- if (!el->l_recs[i].e_clusters) {
- el->l_recs[i].e_cpos = 0;
- el->l_recs[i].e_blkno = 0;
- BUG_ON(!el->l_next_free_rec);
- le16_add_cpu(&el->l_next_free_rec, -1);
- }
- if (i == 1 && ocfs2_is_empty_extent(&el->l_recs[0])) {
- el->l_recs[0].e_cpos = 0;
- el->l_recs[0].e_blkno = 0;
- el->l_next_free_rec = 0;
- }
-
- mlog(0, "extent block %llu, after: record %d: "
- "(%u, %u, %llu), next = %u\n",
- (unsigned long long)le64_to_cpu(eb->h_blkno), i,
- le32_to_cpu(el->l_recs[i].e_cpos),
- le32_to_cpu(el->l_recs[i].e_clusters),
- (unsigned long long)le64_to_cpu(el->l_recs[i].e_blkno),
- le16_to_cpu(el->l_next_free_rec));
-
- status = ocfs2_journal_dirty(handle, eb_bh);
+ if (delete_blk) {
+ status = ocfs2_truncate_log_append(osb, handle, delete_blk,
+ clusters_to_del);
if (status < 0) {
mlog_errno(status);
goto bail;
}
-
- if (!el->l_next_free_rec) {
- mlog(0, "deleting this extent block.\n");
-
- ocfs2_remove_from_cache(inode, eb_bh);
-
- BUG_ON(el->l_recs[0].e_clusters);
- BUG_ON(el->l_recs[0].e_cpos);
- BUG_ON(el->l_recs[0].e_blkno);
-
- /*
- * We need to remove this extent block from
- * the list above it.
- *
- * Since we've passed it already in this loop,
- * no need to worry about journaling.
- */
- el = path->p_node[index - 1].el;
- i = le16_to_cpu(el->l_next_free_rec) - 1;
- BUG_ON(i < 0);
- el->l_recs[i].e_cpos = 0;
- el->l_recs[i].e_clusters = 0;
- el->l_recs[i].e_blkno = 0;
- le16_add_cpu(&el->l_next_free_rec, -1);
-
- if (eb->h_suballoc_slot == 0) {
- /*
- * This code only understands how to
- * lock the suballocator in slot 0,
- * which is fine because allocation is
- * only ever done out of that
- * suballocator too. A future version
- * might change that however, so avoid
- * a free if we don't know how to
- * handle it. This way an fs incompat
- * bit will not be necessary.
- */
- status = ocfs2_free_extent_block(handle,
- tc->tc_ext_alloc_inode,
- tc->tc_ext_alloc_bh,
- eb);
- if (status < 0) {
- mlog_errno(status);
- goto bail;
- }
- }
- }
- index++;
- }
-
- BUG_ON(!delete_blk);
- status = ocfs2_truncate_log_append(osb, handle, delete_blk,
- clusters_to_del);
- if (status < 0) {
- mlog_errno(status);
- goto bail;
}
status = 0;
bail:
goto bail;
}
start:
+ /*
+ * Check that we still have allocation to delete.
+ */
+ if (OCFS2_I(inode)->ip_clusters == 0) {
+ status = 0;
+ goto bail;
+ }
+
/*
* Truncate always works against the rightmost tree branch.
*/
* - no record needs to be removed (truncate has completed)
*/
el = path_leaf_el(path);
+ if (le16_to_cpu(el->l_next_free_rec) == 0) {
+ ocfs2_error(inode->i_sb,
+ "Inode %llu has empty extent block at %llu\n",
+ (unsigned long long)OCFS2_I(inode)->ip_blkno,
+ (unsigned long long)path_leaf_bh(path)->b_blocknr);
+ status = -EROFS;
+ goto bail;
+ }
+
i = le16_to_cpu(el->l_next_free_rec) - 1;
range = le32_to_cpu(el->l_recs[i].e_cpos) +
le32_to_cpu(el->l_recs[i].e_clusters);
ocfs2_reinit_path(path, 1);
/*
- * Only loop if we still have allocation.
+ * The check above will catch the case where we've truncated
+ * away all allocation.
*/
- if (OCFS2_I(inode)->ip_clusters)
- goto start;
+ goto start;
+
bail:
up_write(&OCFS2_I(inode)->ip_alloc_sem);
"%llu\n", fe->i_clusters, new_i_clusters,
(unsigned long long)fe->i_size);
- if (!ocfs2_sparse_alloc(osb) &&
- le32_to_cpu(fe->i_clusters) <= new_i_clusters) {
- ocfs2_error(inode->i_sb, "Dinode %llu has cluster count "
- "%u and size %llu whereas struct inode has "
- "cluster count %u and size %llu which caused an "
- "invalid truncate to %u clusters.",
- (unsigned long long)le64_to_cpu(fe->i_blkno),
- le32_to_cpu(fe->i_clusters),
- (unsigned long long)le64_to_cpu(fe->i_size),
- OCFS2_I(inode)->ip_clusters, i_size_read(inode),
- new_i_clusters);
- mlog_meta_lvb(ML_ERROR, &OCFS2_I(inode)->ip_meta_lockres);
- status = -EIO;
- goto bail;
- }
-
*tc = kzalloc(sizeof(struct ocfs2_truncate_context), GFP_KERNEL);
if (!(*tc)) {
status = -ENOMEM;
projects / linux-2.6 / commitdiff