[PATCH] UBIFS: introduce LEB overhead

Artem Bityutskiy
2008-08-31T13:17:59Z

From: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>

This is a preparational patch for the following statfs()
report fix.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
---
fs/ubifs/super.c | 6 ++++++
fs/ubifs/ubifs.h | 5 +++++
2 files changed, 11 insertions(+), 0 deletions(-)

diff --git a/fs/ubifs/super.c b/fs/ubifs/super.c
index 1018053..be23fd3 100644
--- a/fs/ubifs/super.c
+++ b/fs/ubifs/super.c
@@ -530,6 +530,12 @@ static int init_constants_early(struct ubifs_info *c)
c->dead_wm = ALIGN(MIN_WRITE_SZ, c->min_io_size);
c->dark_wm = ALIGN(UBIFS_MAX_NODE_SZ, c->min_io_size);

+ /*
+ * Calculate how many bytes would be wasted at the end of LEB if it was
+ * fully filled with data nodes of maximum size. This is used in
+ * calculations when reporting free space.
+ */
+ c->leb_overhead = c->leb_size % UBIFS_MAX_DATA_NODE_SZ;
return 0;
}

diff --git a/fs/ubifs/ubifs.h b/fs/ubifs/ubifs.h
index 681d46e..57e5854 100644
--- a/fs/ubifs/ubifs.h
+++ b/fs/ubifs/ubifs.h
@@ -995,6 +995,9 @@ struct ubifs_mount_opts {
* @max_idx_node_sz: maximum indexing node aligned on 8-bytes boundary
* @max_inode_sz: maximum possible inode size in bytes
* @max_znode_sz: size of znode in bytes
+ *
+ * @leb_overhead: how many bytes are wasted in an LEB when it is filled with
+ * data nodes of maximum size - used in free space reporting
* @dead_wm: LEB dead space watermark
* @dark_wm: LEB dark space watermark
* @block_cnt: count of 4KiB blocks on the FS
@@ -1226,6 +1229,8 @@ struct ubifs_info {
int max_idx_node_sz;
long long max_inode_sz;
int max_znode_sz;
+
+ int leb_overhead;
int dead_wm;
int dark_wm;
int block_cnt;
--
1.5.4.1