From 77d0268cb28de75fd4410a4cb3df2e3297a0df1b Mon Sep 17 00:00:00 2001
From: Zach Brown <zab@versity.com>
Date: Thu, 9 Feb 2017 15:47:02 -0800
Subject: [PATCH] Add printing xattrs

For now we only print the xattr names, not the values.

Signed-off-by: Zach Brown <zab@versity.com>
---
 utils/src/format.h | 37 +++++++++++++++++++++++++------------
 utils/src/print.c  | 34 +++++++++++++++-------------------
 2 files changed, 40 insertions(+), 31 deletions(-)

diff --git a/utils/src/format.h b/utils/src/format.h
index 0d5edcfc..83c4d5d8 100644
--- a/utils/src/format.h
+++ b/utils/src/format.h
@@ -231,9 +231,7 @@ struct scoutfs_key {
  * have to stress about cleverly allocating the types.
  */
 #define SCOUTFS_INODE_KEY		1
-#define SCOUTFS_XATTR_KEY		2
-#define SCOUTFS_XATTR_NAME_HASH_KEY	3
-#define SCOUTFS_XATTR_VAL_HASH_KEY	4
+#define SCOUTFS_XATTR_KEY		3
 #define SCOUTFS_DIRENT_KEY		5
 #define SCOUTFS_READDIR_KEY		6
 #define SCOUTFS_LINK_BACKREF_KEY	7
@@ -286,6 +284,23 @@ struct scoutfs_data_key {
 	__be64 block;
 } __packed;
 
+/* value is each item's part of the full xattr value for the off/len */
+struct scoutfs_xattr_key {
+	__u8 type;
+	__be64 ino;
+	__u8 name[0];
+} __packed;
+
+struct scoutfs_xattr_key_footer {
+	__u8 null;
+	__u8 part;
+} __packed;
+
+struct scoutfs_xattr_val_header {
+	__le16 part_len;
+	__u8 last_part;
+} __packed;
+
 struct scoutfs_btree_root {
 	u8 height;
 	struct scoutfs_block_ref ref;
@@ -447,6 +462,13 @@ struct scoutfs_dirent {
 /* S32_MAX avoids the (int) sign bit and might avoid sloppy bugs */
 #define SCOUTFS_LINK_MAX S32_MAX
 
+#define SCOUTFS_XATTR_MAX_NAME_LEN 255
+#define SCOUTFS_XATTR_MAX_SIZE 65536
+#define SCOUTFS_XATTR_PART_SIZE \
+	(SCOUTFS_BLOCK_SIZE - sizeof(struct scoutfs_xattr_val_header))
+#define SCOUTFS_XATTR_MAX_PARTS \
+	DIV_ROUND_UP(SCOUTFS_XATTR_MAX_SIZE, SCOUTFS_XATTR_PART_SIZE)
+
 /*
  * We only use 31 bits for readdir positions so that we don't confuse
  * old signed 32bit f_pos applications or those on the other side of
@@ -470,15 +492,6 @@ enum {
 	SCOUTFS_DT_WHT,
 };
 
-#define SCOUTFS_MAX_XATTR_LEN 255
-#define SCOUTFS_XATTR_NAME_HASH_MASK 7ULL
-
-struct scoutfs_xattr {
-	__u8 name_len;
-	__u8 value_len;
-	__u8 name[0];
-} __packed;
-
 struct scoutfs_extent {
 	__le64	blkno;
 	__le64	len;
diff --git a/utils/src/print.c b/utils/src/print.c
index 2f98717f..ac8a5975 100644
--- a/utils/src/print.c
+++ b/utils/src/print.c
@@ -111,25 +111,6 @@ static void print_orphan(void *key, int key_len, void *val, int val_len)
 	printf("    orphan: ino %llu\n", be64_to_cpu(okey->ino));
 }
 
-#if 0
-
-static void print_xattr(struct scoutfs_xattr *xat)
-{
-	/* XXX check lengths */
-
-	printf("      xattr: name %.*s val_len %u\n",
-	       xat->name_len, xat->name, xat->value_len);
-}
-
-static void print_xattr_val_hash(__le64 *refcount)
-{
-	/* XXX check lengths */
-
-	printf("      xattr_val_hash: refcount %llu\n",
-	       le64_to_cpu(*refcount));
-}
-#endif
-
 static u8 *global_printable_name(u8 *name, int name_len)
 {
 	static u8 name_buf[SCOUTFS_NAME_LEN + 1];
@@ -143,6 +124,20 @@ static u8 *global_printable_name(u8 *name, int name_len)
 	return name_buf;
 }
 
+static void print_xattr(void *key, int key_len, void *val, int val_len)
+{
+	struct scoutfs_xattr_key *xkey = key;
+	struct scoutfs_xattr_key_footer *foot = key + key_len - sizeof(*foot);
+	struct scoutfs_xattr_val_header *vh = val;
+	unsigned int name_len = key_len - sizeof(*xkey) - sizeof(*foot);
+	u8 *name = global_printable_name(xkey->name, name_len);
+
+	printf("    xattr: ino %llu part %u part_len %u last_part %u\n"
+	       "      name %s\n",
+	       be64_to_cpu(xkey->ino), foot->part, le16_to_cpu(vh->part_len),
+	       vh->last_part, name);
+}
+
 static void print_dirent(void *key, int key_len, void *val, int val_len)
 {
 	struct scoutfs_dirent_key *dkey = key;
@@ -213,6 +208,7 @@ typedef void (*print_func_t)(void *key, int key_len, void *val, int val_len);
 
 static print_func_t printers[] = {
 	[SCOUTFS_INODE_KEY] = print_inode,
+	[SCOUTFS_XATTR_KEY] = print_xattr,
 	[SCOUTFS_ORPHAN_KEY] = print_orphan,
 	[SCOUTFS_DIRENT_KEY] = print_dirent,
 	[SCOUTFS_READDIR_KEY] = print_readdir,