btrfs-progs: Basic support for extended inode refs

This patch syncs the extended inode ref definitions from kernels ctree.h and
adds support in btrfs-debug-tree for visualizing the state of extended refs
on disk.

Signed-off-by: Mark Fasheh <mfasheh@suse.de>

diff --git a/ctree.h b/ctree.h
index 4da0af5..d0f6062 100644 (file)
--- a/ctree.h
+++ b/ctree.h
@@ -122,6 +122,13 @@ struct btrfs_trans_handle;
  */
 #define BTRFS_NAME_LEN 255
 
+/*
+ * Theoretical limit is larger, but we keep this down to a sane
+ * value. That should limit greatly the possibility of collisions on
+ * inode ref items.
+ */
+#define        BTRFS_LINK_MAX  65535U
+
 /* 32 bytes in various csum fields */
 #define BTRFS_CSUM_SIZE 32
 
@@ -424,6 +431,7 @@ struct btrfs_super_block {
 #define BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL  (1ULL << 1)
 #define BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS    (1ULL << 2)
 #define BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO    (1ULL << 3)
+
 /*
  * some patches floated around with a second compression method
  * lets save that incompat here for when they do get in
@@ -438,6 +446,7 @@ struct btrfs_super_block {
  */
 #define BTRFS_FEATURE_INCOMPAT_BIG_METADATA     (1ULL << 5)
 
+#define BTRFS_FEATURE_INCOMPAT_EXTENDED_IREF   (1ULL << 6)
 
 #define BTRFS_FEATURE_COMPAT_SUPP              0ULL
 #define BTRFS_FEATURE_COMPAT_RO_SUPP           0ULL
@@ -446,7 +455,8 @@ struct btrfs_super_block {
         BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL |        \
         BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO |          \
         BTRFS_FEATURE_INCOMPAT_BIG_METADATA |          \
-        BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS)
+        BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS |          \
+        BTRFS_FEATURE_INCOMPAT_EXTENDED_IREF)
 
 /*
  * A leaf is full of items. offset and size tell us where to find
@@ -585,6 +595,13 @@ struct btrfs_inode_ref {
        /* name goes here */
 } __attribute__ ((__packed__));
 
+struct btrfs_inode_extref {
+       __le64 parent_objectid;
+       __le64 index;
+       __le16 name_len;
+       __u8   name[0]; /* name goes here */
+} __attribute__ ((__packed__));
+
 struct btrfs_timespec {
        __le64 sec;
        __le32 nsec;
@@ -960,6 +977,7 @@ struct btrfs_root {
  */
 #define BTRFS_INODE_ITEM_KEY           1
 #define BTRFS_INODE_REF_KEY            12
+#define BTRFS_INODE_EXTREF_KEY         13
 #define BTRFS_XATTR_ITEM_KEY           24
 #define BTRFS_ORPHAN_ITEM_KEY          48
 
@@ -1259,6 +1277,13 @@ BTRFS_SETGET_FUNCS(inode_ref_name_len, struct btrfs_inode_ref, name_len, 16);
 BTRFS_SETGET_STACK_FUNCS(stack_inode_ref_name_len, struct btrfs_inode_ref, name_len, 16);
 BTRFS_SETGET_FUNCS(inode_ref_index, struct btrfs_inode_ref, index, 64);
 
+/* struct btrfs_inode_extref */
+BTRFS_SETGET_FUNCS(inode_extref_parent, struct btrfs_inode_extref,
+                  parent_objectid, 64);
+BTRFS_SETGET_FUNCS(inode_extref_name_len, struct btrfs_inode_extref,
+                  name_len, 16);
+BTRFS_SETGET_FUNCS(inode_extref_index, struct btrfs_inode_extref, index, 64);
+
 /* struct btrfs_inode_item */
 BTRFS_SETGET_FUNCS(inode_generation, struct btrfs_inode_item, generation, 64);
 BTRFS_SETGET_FUNCS(inode_sequence, struct btrfs_inode_item, sequence, 64);

diff --git a/print-tree.c b/print-tree.c
index e70e7f7..5739e19 100644 (file)
--- a/print-tree.c
+++ b/print-tree.c
@@ -61,6 +61,42 @@ static int print_dir_item(struct extent_buffer *eb, struct btrfs_item *item,
        return 0;
 }
 
+static int print_inode_extref_item(struct extent_buffer *eb,
+                                  struct btrfs_item *item,
+                                  struct btrfs_inode_extref *extref)
+{
+       u32 total;
+       u32 cur = 0;
+       u32 len;
+       u32 name_len = 0;
+       u64 index = 0;
+       u64 parent_objid;
+       char namebuf[BTRFS_NAME_LEN];
+
+       total = btrfs_item_size(eb, item);
+
+       while (cur < total) {
+               index = btrfs_inode_extref_index(eb, extref);
+               name_len = btrfs_inode_extref_name_len(eb, extref);
+               parent_objid = btrfs_inode_extref_parent(eb, extref);
+
+               len = (name_len <= sizeof(namebuf))? name_len: sizeof(namebuf);
+
+               read_extent_buffer(eb, namebuf, (unsigned long)(extref->name), len);
+
+               printf("\t\tinode extref index %llu parent %llu namelen %u "
+                      "name: %.*s\n",
+                      (unsigned long long)index,
+                      (unsigned long long)parent_objid,
+                      name_len, len, namebuf);
+
+               len = sizeof(*extref) + name_len;
+               extref = (struct btrfs_inode_extref *)((char *)extref + len);
+               cur += len;
+       }
+       return 0;
+}
+
 static int print_inode_ref_item(struct extent_buffer *eb, struct btrfs_item *item,
                                struct btrfs_inode_ref *ref)
 {
@@ -371,6 +407,9 @@ static void print_key_type(u64 objectid, u8 type)
        case BTRFS_INODE_REF_KEY:
                printf("INODE_REF");
                break;
+       case BTRFS_INODE_EXTREF_KEY:
+               printf("INODE_EXTREF");
+               break;
        case BTRFS_DIR_ITEM_KEY:
                printf("DIR_ITEM");
                break;
@@ -582,6 +621,7 @@ void btrfs_print_leaf(struct btrfs_root *root, struct extent_buffer *l)
        struct btrfs_extent_data_ref *dref;
        struct btrfs_shared_data_ref *sref;
        struct btrfs_inode_ref *iref;
+       struct btrfs_inode_extref *iref2;
        struct btrfs_dev_extent *dev_extent;
        struct btrfs_disk_key disk_key;
        struct btrfs_block_group_item bg_item;
@@ -629,6 +669,10 @@ void btrfs_print_leaf(struct btrfs_root *root, struct extent_buffer *l)
                        iref = btrfs_item_ptr(l, i, struct btrfs_inode_ref);
                        print_inode_ref_item(l, item, iref);
                        break;
+               case BTRFS_INODE_EXTREF_KEY:
+                       iref2 = btrfs_item_ptr(l, i, struct btrfs_inode_extref);
+                       print_inode_extref_item(l, item, iref2);
+                       break;
                case BTRFS_DIR_ITEM_KEY:
                case BTRFS_DIR_INDEX_KEY:
                case BTRFS_XATTR_ITEM_KEY: