ceph: add dir_layout to inode
Add a ceph_dir_layout to the inode, and calculate dentry hash values based
on the parent directory's specified dir_hash function. This is needed
because the old default Linux dcache hash function is extremely week and
leads to a poor distribution of files among dir fragments.
Signed-off-by: Sage Weil <sage@newdream.net>
diff --git a/include/linux/ceph/ceph_fs.h b/include/linux/ceph/ceph_fs.h
index c3c74ae..09dcc0c 100644
--- a/include/linux/ceph/ceph_fs.h
+++ b/include/linux/ceph/ceph_fs.h
@@ -43,6 +43,10 @@
#define CEPH_FEATURE_NOSRCADDR (1<<1)
#define CEPH_FEATURE_MONCLOCKCHECK (1<<2)
#define CEPH_FEATURE_FLOCK (1<<3)
+#define CEPH_FEATURE_SUBSCRIBE2 (1<<4)
+#define CEPH_FEATURE_MONNAMES (1<<5)
+#define CEPH_FEATURE_RECONNECT_SEQ (1<<6)
+#define CEPH_FEATURE_DIRLAYOUTHASH (1<<7)
/*
@@ -55,10 +59,10 @@
__le32 fl_stripe_count; /* over this many objects */
__le32 fl_object_size; /* until objects are this big, then move to
new objects */
- __le32 fl_cas_hash; /* 0 = none; 1 = sha256 */
+ __le32 fl_cas_hash; /* UNUSED. 0 = none; 1 = sha256 */
/* pg -> disk layout */
- __le32 fl_object_stripe_unit; /* for per-object parity, if any */
+ __le32 fl_object_stripe_unit; /* UNUSED. for per-object parity, if any */
/* object -> pg layout */
__le32 fl_pg_preferred; /* preferred primary for pg (-1 for none) */
@@ -69,6 +73,12 @@
int ceph_file_layout_is_valid(const struct ceph_file_layout *layout);
+struct ceph_dir_layout {
+ __u8 dl_dir_hash; /* see ceph_hash.h for ids */
+ __u8 dl_unused1;
+ __u16 dl_unused2;
+ __u32 dl_unused3;
+} __attribute__ ((packed));
/* crypto algorithms */
#define CEPH_CRYPTO_NONE 0x0
@@ -457,7 +467,7 @@
struct ceph_timespec rctime;
struct ceph_frag_tree_head fragtree; /* (must be at end of struct) */
} __attribute__ ((packed));
-/* followed by frag array, then symlink string, then xattr blob */
+/* followed by frag array, symlink string, dir layout, xattr blob */
/* reply_lease follows dname, and reply_inode */
struct ceph_mds_reply_lease {