ocfs2: make room for unwritten extents flag
Due to the size of our group bitmaps, we'll never have a leaf node extent
record with more than 16 bits worth of clusters. Split e_clusters up so that
leaf nodes can get a flags field where we can mark unwritten extents.
Interior nodes whose length references all the child nodes beneath it can't
split their e_clusters field, so we use a union to preserve sizing there.
Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
diff --git a/fs/ocfs2/alloc.c b/fs/ocfs2/alloc.c
index 027cf5d..0eab0d3 100644
--- a/fs/ocfs2/alloc.c
+++ b/fs/ocfs2/alloc.c
@@ -218,20 +218,32 @@
CONTIG_RIGHT
};
+
+/*
+ * NOTE: ocfs2_block_extent_contig(), ocfs2_extents_adjacent() and
+ * ocfs2_extent_contig only work properly against leaf nodes!
+ */
static int ocfs2_block_extent_contig(struct super_block *sb,
struct ocfs2_extent_rec *ext,
u64 blkno)
{
- return blkno == (le64_to_cpu(ext->e_blkno) +
- ocfs2_clusters_to_blocks(sb,
- le32_to_cpu(ext->e_clusters)));
+ u64 blk_end = le64_to_cpu(ext->e_blkno);
+
+ blk_end += ocfs2_clusters_to_blocks(sb,
+ le16_to_cpu(ext->e_leaf_clusters));
+
+ return blkno == blk_end;
}
static int ocfs2_extents_adjacent(struct ocfs2_extent_rec *left,
struct ocfs2_extent_rec *right)
{
- return (le32_to_cpu(left->e_cpos) + le32_to_cpu(left->e_clusters) ==
- le32_to_cpu(right->e_cpos));
+ u32 left_range;
+
+ left_range = le32_to_cpu(left->e_cpos) +
+ le16_to_cpu(left->e_leaf_clusters);
+
+ return (left_range == le32_to_cpu(right->e_cpos));
}
static enum ocfs2_contig_type
@@ -430,7 +442,7 @@
i = le16_to_cpu(el->l_next_free_rec) - 1;
return le32_to_cpu(el->l_recs[i].e_cpos) +
- le32_to_cpu(el->l_recs[i].e_clusters);
+ ocfs2_rec_clusters(el, &el->l_recs[i]);
}
/*
@@ -442,7 +454,7 @@
* for the new last extent block.
*
* the new branch will be 'empty' in the sense that every block will
- * contain a single record with e_clusters == 0.
+ * contain a single record with cluster count == 0.
*/
static int ocfs2_add_branch(struct ocfs2_super *osb,
handle_t *handle,
@@ -532,7 +544,12 @@
*/
eb_el->l_recs[0].e_cpos = cpu_to_le32(new_cpos);
eb_el->l_recs[0].e_blkno = cpu_to_le64(next_blkno);
- eb_el->l_recs[0].e_clusters = cpu_to_le32(0);
+ /*
+ * eb_el isn't always an interior node, but even leaf
+ * nodes want a zero'd flags and reserved field so
+ * this gets the whole 32 bits regardless of use.
+ */
+ eb_el->l_recs[0].e_int_clusters = cpu_to_le32(0);
if (!eb_el->l_tree_depth)
new_last_eb_blk = le64_to_cpu(eb->h_blkno);
@@ -577,7 +594,7 @@
i = le16_to_cpu(el->l_next_free_rec);
el->l_recs[i].e_blkno = cpu_to_le64(next_blkno);
el->l_recs[i].e_cpos = cpu_to_le32(new_cpos);
- el->l_recs[i].e_clusters = 0;
+ el->l_recs[i].e_int_clusters = 0;
le16_add_cpu(&el->l_next_free_rec, 1);
/* fe needs a new last extent block pointer, as does the
@@ -662,11 +679,8 @@
/* copy the fe data into the new extent block */
eb_el->l_tree_depth = fe_el->l_tree_depth;
eb_el->l_next_free_rec = fe_el->l_next_free_rec;
- for(i = 0; i < le16_to_cpu(fe_el->l_next_free_rec); i++) {
- eb_el->l_recs[i].e_cpos = fe_el->l_recs[i].e_cpos;
- eb_el->l_recs[i].e_clusters = fe_el->l_recs[i].e_clusters;
- eb_el->l_recs[i].e_blkno = fe_el->l_recs[i].e_blkno;
- }
+ for(i = 0; i < le16_to_cpu(fe_el->l_next_free_rec); i++)
+ eb_el->l_recs[i] = fe_el->l_recs[i];
status = ocfs2_journal_dirty(handle, new_eb_bh);
if (status < 0) {
@@ -687,12 +701,9 @@
le16_add_cpu(&fe_el->l_tree_depth, 1);
fe_el->l_recs[0].e_cpos = 0;
fe_el->l_recs[0].e_blkno = eb->h_blkno;
- fe_el->l_recs[0].e_clusters = cpu_to_le32(new_clusters);
- for(i = 1; i < le16_to_cpu(fe_el->l_next_free_rec); i++) {
- fe_el->l_recs[i].e_cpos = 0;
- fe_el->l_recs[i].e_clusters = 0;
- fe_el->l_recs[i].e_blkno = 0;
- }
+ fe_el->l_recs[0].e_int_clusters = cpu_to_le32(new_clusters);
+ for(i = 1; i < le16_to_cpu(fe_el->l_next_free_rec); i++)
+ memset(&fe_el->l_recs[i], 0, sizeof(struct ocfs2_extent_rec));
fe_el->l_next_free_rec = cpu_to_le16(1);
/* If this is our 1st tree depth shift, then last_eb_blk
@@ -817,9 +828,13 @@
return status;
}
+/*
+ * This is only valid for leaf nodes, which are the only ones that can
+ * have empty extents anyway.
+ */
static inline int ocfs2_is_empty_extent(struct ocfs2_extent_rec *rec)
{
- return !rec->e_clusters;
+ return !rec->e_leaf_clusters;
}
/*
@@ -930,6 +945,8 @@
{
int next_free = le16_to_cpu(el->l_next_free_rec);
+ BUG_ON(le16_to_cpu(el->l_tree_depth) != 0);
+
if (next_free == 0)
goto set_and_inc;
@@ -1034,7 +1051,7 @@
* rightmost record.
*/
range = le32_to_cpu(rec->e_cpos) +
- le32_to_cpu(rec->e_clusters);
+ ocfs2_rec_clusters(el, rec);
if (cpos >= le32_to_cpu(rec->e_cpos) && cpos < range)
break;
}
@@ -1195,21 +1212,21 @@
*/
left_clusters = le32_to_cpu(right_child_el->l_recs[0].e_cpos);
left_clusters -= le32_to_cpu(left_rec->e_cpos);
- left_rec->e_clusters = cpu_to_le32(left_clusters);
+ left_rec->e_int_clusters = cpu_to_le32(left_clusters);
/*
* Calculate the rightmost cluster count boundary before
- * moving cpos - we will need to adjust e_clusters after
+ * moving cpos - we will need to adjust clusters after
* updating e_cpos to keep the same highest cluster count.
*/
right_end = le32_to_cpu(right_rec->e_cpos);
- right_end += le32_to_cpu(right_rec->e_clusters);
+ right_end += le32_to_cpu(right_rec->e_int_clusters);
right_rec->e_cpos = left_rec->e_cpos;
le32_add_cpu(&right_rec->e_cpos, left_clusters);
right_end -= le32_to_cpu(right_rec->e_cpos);
- right_rec->e_clusters = cpu_to_le32(right_end);
+ right_rec->e_int_clusters = cpu_to_le32(right_end);
}
/*
@@ -1452,6 +1469,8 @@
u64 blkno;
struct ocfs2_extent_list *el;
+ BUG_ON(path->p_tree_depth == 0);
+
*cpos = 0;
blkno = path_leaf_bh(path)->b_blocknr;
@@ -1486,7 +1505,9 @@
}
*cpos = le32_to_cpu(el->l_recs[j - 1].e_cpos);
- *cpos = *cpos + le32_to_cpu(el->l_recs[j - 1].e_clusters) - 1;
+ *cpos = *cpos + ocfs2_rec_clusters(el,
+ &el->l_recs[j - 1]);
+ *cpos = *cpos - 1;
goto out;
}
}
@@ -1715,7 +1736,7 @@
unsigned int range;
struct ocfs2_extent_rec *rec;
- BUG_ON(el->l_tree_depth);
+ BUG_ON(le16_to_cpu(el->l_tree_depth) != 0);
/*
* Contiguous insert - either left or right.
@@ -1726,8 +1747,8 @@
rec->e_blkno = insert_rec->e_blkno;
rec->e_cpos = insert_rec->e_cpos;
}
- le32_add_cpu(&rec->e_clusters,
- le32_to_cpu(insert_rec->e_clusters));
+ le16_add_cpu(&rec->e_leaf_clusters,
+ le16_to_cpu(insert_rec->e_leaf_clusters));
return;
}
@@ -1748,7 +1769,8 @@
if (insert->ins_appending == APPEND_TAIL) {
i = le16_to_cpu(el->l_next_free_rec) - 1;
rec = &el->l_recs[i];
- range = le32_to_cpu(rec->e_cpos) + le32_to_cpu(rec->e_clusters);
+ range = le32_to_cpu(rec->e_cpos)
+ + le16_to_cpu(rec->e_leaf_clusters);
BUG_ON(le32_to_cpu(insert_rec->e_cpos) < range);
mlog_bug_on_msg(le16_to_cpu(el->l_next_free_rec) >=
@@ -1761,9 +1783,9 @@
le16_to_cpu(el->l_count),
le16_to_cpu(el->l_next_free_rec),
le32_to_cpu(el->l_recs[i].e_cpos),
- le32_to_cpu(el->l_recs[i].e_clusters),
+ le16_to_cpu(el->l_recs[i].e_leaf_clusters),
le32_to_cpu(insert_rec->e_cpos),
- le32_to_cpu(insert_rec->e_clusters));
+ le16_to_cpu(insert_rec->e_leaf_clusters));
i++;
el->l_recs[i] = *insert_rec;
le16_add_cpu(&el->l_next_free_rec, 1);
@@ -1806,6 +1828,12 @@
*ret_left_path = NULL;
/*
+ * This shouldn't happen for non-trees. The extent rec cluster
+ * count manipulation below only works for interior nodes.
+ */
+ BUG_ON(right_path->p_tree_depth == 0);
+
+ /*
* If our appending insert is at the leftmost edge of a leaf,
* then we might need to update the rightmost records of the
* neighboring path.
@@ -1863,6 +1891,8 @@
bh = path_root_bh(right_path);
i = 0;
while (1) {
+ struct ocfs2_extent_rec *rec;
+
next_free = le16_to_cpu(el->l_next_free_rec);
if (next_free == 0) {
ocfs2_error(inode->i_sb,
@@ -1872,16 +1902,19 @@
goto out;
}
- el->l_recs[next_free - 1].e_clusters = insert_rec->e_cpos;
- le32_add_cpu(&el->l_recs[next_free - 1].e_clusters,
- le32_to_cpu(insert_rec->e_clusters));
- le32_add_cpu(&el->l_recs[next_free - 1].e_clusters,
- -le32_to_cpu(el->l_recs[next_free - 1].e_cpos));
+ rec = &el->l_recs[next_free - 1];
+
+ rec->e_int_clusters = insert_rec->e_cpos;
+ le32_add_cpu(&rec->e_int_clusters,
+ le16_to_cpu(insert_rec->e_leaf_clusters));
+ le32_add_cpu(&rec->e_int_clusters,
+ -le32_to_cpu(rec->e_cpos));
ret = ocfs2_journal_dirty(handle, bh);
if (ret)
mlog_errno(ret);
+ /* Don't touch the leaf node */
if (++i >= right_path->p_tree_depth)
break;
@@ -2068,7 +2101,7 @@
out_update_clusters:
ocfs2_update_dinode_clusters(inode, di,
- le32_to_cpu(insert_rec->e_clusters));
+ le16_to_cpu(insert_rec->e_leaf_clusters));
ret = ocfs2_journal_dirty(handle, di_bh);
if (ret)
@@ -2089,6 +2122,8 @@
int i;
enum ocfs2_contig_type contig_type = CONTIG_NONE;
+ BUG_ON(le16_to_cpu(el->l_tree_depth) != 0);
+
for(i = 0; i < le16_to_cpu(el->l_next_free_rec); i++) {
contig_type = ocfs2_extent_contig(inode, &el->l_recs[i],
insert_rec);
@@ -2120,7 +2155,7 @@
insert->ins_appending = APPEND_NONE;
- BUG_ON(el->l_tree_depth);
+ BUG_ON(le16_to_cpu(el->l_tree_depth) != 0);
if (!el->l_next_free_rec)
goto set_tail_append;
@@ -2134,7 +2169,8 @@
i = le16_to_cpu(el->l_next_free_rec) - 1;
rec = &el->l_recs[i];
- if (cpos >= (le32_to_cpu(rec->e_cpos) + le32_to_cpu(rec->e_clusters)))
+ if (cpos >=
+ (le32_to_cpu(rec->e_cpos) + le16_to_cpu(rec->e_leaf_clusters)))
goto set_tail_append;
return;
@@ -2242,7 +2278,7 @@
* The insert code isn't quite ready to deal with all cases of
* left contiguousness. Specifically, if it's an insert into
* the 1st record in a leaf, it will require the adjustment of
- * e_clusters on the last record of the path directly to it's
+ * cluster count on the last record of the path directly to it's
* left. For now, just catch that case and fool the layers
* above us. This works just fine for tree_depth == 0, which
* is why we allow that above.
@@ -2310,9 +2346,10 @@
(unsigned long long)OCFS2_I(inode)->ip_blkno, cpos,
OCFS2_I(inode)->ip_clusters);
+ memset(&rec, 0, sizeof(rec));
rec.e_cpos = cpu_to_le32(cpos);
rec.e_blkno = cpu_to_le64(start_blk);
- rec.e_clusters = cpu_to_le32(new_clusters);
+ rec.e_leaf_clusters = cpu_to_le16(new_clusters);
status = ocfs2_figure_insert_type(inode, fe_bh, &last_eb_bh, &rec,
&insert);
@@ -2981,7 +3018,7 @@
* Check it we'll only be trimming off the end of this
* cluster.
*/
- if (le16_to_cpu(rec->e_clusters) > clusters_to_del)
+ if (le16_to_cpu(rec->e_leaf_clusters) > clusters_to_del)
goto out;
}
@@ -3061,11 +3098,11 @@
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),
+ ocfs2_rec_clusters(el, rec),
(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);
+ BUG_ON(ocfs2_rec_clusters(el, rec) < clusters_to_del);
if (le16_to_cpu(el->l_tree_depth) == 0) {
/*
@@ -3107,13 +3144,13 @@
goto find_tail_record;
}
- le32_add_cpu(&rec->e_clusters, -clusters_to_del);
+ le16_add_cpu(&rec->e_leaf_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 = le16_to_cpu(rec->e_leaf_clusters);
new_edge += le32_to_cpu(rec->e_cpos);
/*
@@ -3121,12 +3158,12 @@
*/
*delete_start = le64_to_cpu(rec->e_blkno)
+ ocfs2_clusters_to_blocks(inode->i_sb,
- le32_to_cpu(rec->e_clusters));
+ le16_to_cpu(rec->e_leaf_clusters));
/*
* If it's now empty, remove this record.
*/
- if (le32_to_cpu(rec->e_clusters) == 0) {
+ if (le16_to_cpu(rec->e_leaf_clusters) == 0) {
memset(rec, 0,
sizeof(struct ocfs2_extent_rec));
le16_add_cpu(&el->l_next_free_rec, -1);
@@ -3152,15 +3189,15 @@
if (new_edge == 0)
goto delete;
- rec->e_clusters = cpu_to_le32(new_edge);
- le32_add_cpu(&rec->e_clusters,
+ rec->e_int_clusters = cpu_to_le32(new_edge);
+ le32_add_cpu(&rec->e_int_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);
+ BUG_ON(le32_to_cpu(rec->e_int_clusters) == 0);
}
delete:
@@ -3173,7 +3210,7 @@
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),
+ le32_to_cpu(rec->e_cpos), ocfs2_rec_clusters(el, rec),
(unsigned long long)le64_to_cpu(rec->e_blkno),
le16_to_cpu(el->l_next_free_rec));
@@ -3195,7 +3232,7 @@
ocfs2_remove_from_cache(inode, bh);
- BUG_ON(le32_to_cpu(el->l_recs[0].e_clusters));
+ BUG_ON(ocfs2_rec_clusters(el, &el->l_recs[0]));
BUG_ON(le32_to_cpu(el->l_recs[0].e_cpos));
BUG_ON(le64_to_cpu(el->l_recs[0].e_blkno));
@@ -3283,7 +3320,7 @@
* Lower levels depend on this never happening, but it's best
* to check it up here before changing the tree.
*/
- if (el->l_tree_depth && ocfs2_is_empty_extent(&el->l_recs[0])) {
+ if (el->l_tree_depth && el->l_recs[0].e_int_clusters == 0) {
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));
@@ -3644,13 +3681,13 @@
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_rec_clusters(el, &el->l_recs[i]);
if (i == 0 && ocfs2_is_empty_extent(&el->l_recs[i])) {
clusters_to_del = 0;
} else if (le32_to_cpu(el->l_recs[i].e_cpos) >= new_highest_cpos) {
- clusters_to_del = le32_to_cpu(el->l_recs[i].e_clusters);
+ clusters_to_del = ocfs2_rec_clusters(el, &el->l_recs[i]);
} else if (range > new_highest_cpos) {
- clusters_to_del = (le32_to_cpu(el->l_recs[i].e_clusters) +
+ clusters_to_del = (ocfs2_rec_clusters(el, &el->l_recs[i]) +
le32_to_cpu(el->l_recs[i].e_cpos)) -
new_highest_cpos;
} else {
diff --git a/fs/ocfs2/alloc.h b/fs/ocfs2/alloc.h
index 3cb39cd..fbcb593 100644
--- a/fs/ocfs2/alloc.h
+++ b/fs/ocfs2/alloc.h
@@ -85,4 +85,23 @@
int ocfs2_find_leaf(struct inode *inode, struct ocfs2_extent_list *root_el,
u32 cpos, struct buffer_head **leaf_bh);
+/*
+ * Helper function to look at the # of clusters in an extent record.
+ */
+static inline unsigned int ocfs2_rec_clusters(struct ocfs2_extent_list *el,
+ struct ocfs2_extent_rec *rec)
+{
+ /*
+ * Cluster count in extent records is slightly different
+ * between interior nodes and leaf nodes. This is to support
+ * unwritten extents which need a flags field in leaf node
+ * records, thus shrinking the available space for a clusters
+ * field.
+ */
+ if (el->l_tree_depth)
+ return le32_to_cpu(rec->e_int_clusters);
+ else
+ return le16_to_cpu(rec->e_leaf_clusters);
+}
+
#endif /* OCFS2_ALLOC_H */
diff --git a/fs/ocfs2/extent_map.c b/fs/ocfs2/extent_map.c
index 937c272..ea0ce41 100644
--- a/fs/ocfs2/extent_map.c
+++ b/fs/ocfs2/extent_map.c
@@ -50,13 +50,15 @@
int ret = -1;
int i;
struct ocfs2_extent_rec *rec;
- u32 rec_end, rec_start;
+ u32 rec_end, rec_start, clusters;
for(i = 0; i < le16_to_cpu(el->l_next_free_rec); i++) {
rec = &el->l_recs[i];
rec_start = le32_to_cpu(rec->e_cpos);
- rec_end = rec_start + le32_to_cpu(rec->e_clusters);
+ clusters = ocfs2_rec_clusters(el, rec);
+
+ rec_end = rec_start + clusters;
if (v_cluster >= rec_start && v_cluster < rec_end) {
ret = i;
@@ -98,6 +100,15 @@
eb = (struct ocfs2_extent_block *) eb_bh->b_data;
el = &eb->h_list;
+
+ if (el->l_tree_depth) {
+ ocfs2_error(inode->i_sb,
+ "Inode %lu has non zero tree depth in "
+ "leaf block %llu\n", inode->i_ino,
+ (unsigned long long)eb_bh->b_blocknr);
+ ret = -EROFS;
+ goto out;
+ }
}
i = ocfs2_search_extent_list(el, v_cluster);
@@ -118,7 +129,7 @@
ocfs2_error(inode->i_sb, "Inode %lu has bad extent "
"record (%u, %u, 0)", inode->i_ino,
le32_to_cpu(rec->e_cpos),
- le32_to_cpu(rec->e_clusters));
+ ocfs2_rec_clusters(el, rec));
ret = -EROFS;
goto out;
}
@@ -130,7 +141,7 @@
*p_cluster = *p_cluster + coff;
if (num_clusters)
- *num_clusters = le32_to_cpu(rec->e_clusters) - coff;
+ *num_clusters = ocfs2_rec_clusters(el, rec) - coff;
}
out:
diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index f516619..3617601 100644
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -1127,7 +1127,6 @@
size_t count)
{
int ret = 0;
- unsigned int extent_flags;
u32 cpos, clusters, extent_len, phys_cpos;
struct super_block *sb = inode->i_sb;
@@ -1135,14 +1134,13 @@
clusters = ocfs2_clusters_for_bytes(sb, pos + count) - cpos;
while (clusters) {
- ret = ocfs2_get_clusters(inode, cpos, &phys_cpos, &extent_len,
- &extent_flags);
+ ret = ocfs2_get_clusters(inode, cpos, &phys_cpos, &extent_len);
if (ret < 0) {
mlog_errno(ret);
goto out;
}
- if (phys_cpos == 0 || (extent_flags & OCFS2_EXT_UNWRITTEN)) {
+ if (phys_cpos == 0) {
ret = 1;
break;
}
diff --git a/fs/ocfs2/journal.h b/fs/ocfs2/journal.h
index d026b4f..3db5de4 100644
--- a/fs/ocfs2/journal.h
+++ b/fs/ocfs2/journal.h
@@ -390,7 +390,7 @@
/* We may be deleting metadata blocks, so metadata alloc dinode +
one desc. block for each possible delete. */
if (tree_depth && next_free == 1 &&
- le32_to_cpu(last_el->l_recs[i].e_clusters) == clusters_to_del)
+ ocfs2_rec_clusters(last_el, &last_el->l_recs[i]) == clusters_to_del)
credits += 1 + tree_depth;
/* update to the truncate log. */
diff --git a/fs/ocfs2/ocfs2_fs.h b/fs/ocfs2/ocfs2_fs.h
index f010197..7130647 100644
--- a/fs/ocfs2/ocfs2_fs.h
+++ b/fs/ocfs2/ocfs2_fs.h
@@ -156,6 +156,12 @@
#define OCFS2_FL_MODIFIABLE (0x000100FF) /* User modifiable flags */
/*
+ * Extent record flags (e_node.leaf.flags)
+ */
+#define OCFS2_EXT_UNWRITTEN (0x01) /* Extent is allocated but
+ * unwritten */
+
+/*
* ioctl commands
*/
#define OCFS2_IOC_GETFLAGS _IOR('f', 1, long)
@@ -283,10 +289,21 @@
/*
* On disk extent record for OCFS2
* It describes a range of clusters on disk.
+ *
+ * Length fields are divided into interior and leaf node versions.
+ * This leaves room for a flags field (OCFS2_EXT_*) in the leaf nodes.
*/
struct ocfs2_extent_rec {
/*00*/ __le32 e_cpos; /* Offset into the file, in clusters */
- __le32 e_clusters; /* Clusters covered by this extent */
+ union {
+ __le32 e_int_clusters; /* Clusters covered by all children */
+ struct {
+ __le16 e_leaf_clusters; /* Clusters covered by this
+ extent */
+ __u8 e_reserved1;
+ __u8 e_flags; /* Extent flags */
+ };
+ };
__le64 e_blkno; /* Physical disk offset, in blocks */
/*10*/
};