xfs: merge xfs_ag.h into xfs_format.h

More on-disk format consolidation.  A few declarations that weren't on-disk
format related move into better suitable spots.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>

diff --git a/fs/xfs/libxfs/xfs_format.h b/fs/xfs/libxfs/xfs_format.h
index e99d329..9b6e424 100644
--- a/fs/xfs/libxfs/xfs_format.h
+++ b/fs/xfs/libxfs/xfs_format.h
@@ -33,6 +33,249 @@
 struct xfs_buf;
 struct xfs_ifork;
 
+/*
+ * Allocation group header
+ *
+ * This is divided into three structures, placed in sequential 512-byte
+ * buffers after a copy of the superblock (also in a 512-byte buffer).
+ */
+#define	XFS_AGF_MAGIC	0x58414746	/* 'XAGF' */
+#define	XFS_AGI_MAGIC	0x58414749	/* 'XAGI' */
+#define	XFS_AGFL_MAGIC	0x5841464c	/* 'XAFL' */
+#define	XFS_AGF_VERSION	1
+#define	XFS_AGI_VERSION	1
+
+#define	XFS_AGF_GOOD_VERSION(v)	((v) == XFS_AGF_VERSION)
+#define	XFS_AGI_GOOD_VERSION(v)	((v) == XFS_AGI_VERSION)
+
+/*
+ * Btree number 0 is bno, 1 is cnt.  This value gives the size of the
+ * arrays below.
+ */
+#define	XFS_BTNUM_AGF	((int)XFS_BTNUM_CNTi + 1)
+
+/*
+ * The second word of agf_levels in the first a.g. overlaps the EFS
+ * superblock's magic number.  Since the magic numbers valid for EFS
+ * are > 64k, our value cannot be confused for an EFS superblock's.
+ */
+
+typedef struct xfs_agf {
+	/*
+	 * Common allocation group header information
+	 */
+	__be32		agf_magicnum;	/* magic number == XFS_AGF_MAGIC */
+	__be32		agf_versionnum;	/* header version == XFS_AGF_VERSION */
+	__be32		agf_seqno;	/* sequence # starting from 0 */
+	__be32		agf_length;	/* size in blocks of a.g. */
+	/*
+	 * Freespace information
+	 */
+	__be32		agf_roots[XFS_BTNUM_AGF];	/* root blocks */
+	__be32		agf_spare0;	/* spare field */
+	__be32		agf_levels[XFS_BTNUM_AGF];	/* btree levels */
+	__be32		agf_spare1;	/* spare field */
+
+	__be32		agf_flfirst;	/* first freelist block's index */
+	__be32		agf_fllast;	/* last freelist block's index */
+	__be32		agf_flcount;	/* count of blocks in freelist */
+	__be32		agf_freeblks;	/* total free blocks */
+
+	__be32		agf_longest;	/* longest free space */
+	__be32		agf_btreeblks;	/* # of blocks held in AGF btrees */
+	uuid_t		agf_uuid;	/* uuid of filesystem */
+
+	/*
+	 * reserve some contiguous space for future logged fields before we add
+	 * the unlogged fields. This makes the range logging via flags and
+	 * structure offsets much simpler.
+	 */
+	__be64		agf_spare64[16];
+
+	/* unlogged fields, written during buffer writeback. */
+	__be64		agf_lsn;	/* last write sequence */
+	__be32		agf_crc;	/* crc of agf sector */
+	__be32		agf_spare2;
+
+	/* structure must be padded to 64 bit alignment */
+} xfs_agf_t;
+
+#define XFS_AGF_CRC_OFF		offsetof(struct xfs_agf, agf_crc)
+
+#define	XFS_AGF_MAGICNUM	0x00000001
+#define	XFS_AGF_VERSIONNUM	0x00000002
+#define	XFS_AGF_SEQNO		0x00000004
+#define	XFS_AGF_LENGTH		0x00000008
+#define	XFS_AGF_ROOTS		0x00000010
+#define	XFS_AGF_LEVELS		0x00000020
+#define	XFS_AGF_FLFIRST		0x00000040
+#define	XFS_AGF_FLLAST		0x00000080
+#define	XFS_AGF_FLCOUNT		0x00000100
+#define	XFS_AGF_FREEBLKS	0x00000200
+#define	XFS_AGF_LONGEST		0x00000400
+#define	XFS_AGF_BTREEBLKS	0x00000800
+#define	XFS_AGF_UUID		0x00001000
+#define	XFS_AGF_NUM_BITS	13
+#define	XFS_AGF_ALL_BITS	((1 << XFS_AGF_NUM_BITS) - 1)
+
+#define XFS_AGF_FLAGS \
+	{ XFS_AGF_MAGICNUM,	"MAGICNUM" }, \
+	{ XFS_AGF_VERSIONNUM,	"VERSIONNUM" }, \
+	{ XFS_AGF_SEQNO,	"SEQNO" }, \
+	{ XFS_AGF_LENGTH,	"LENGTH" }, \
+	{ XFS_AGF_ROOTS,	"ROOTS" }, \
+	{ XFS_AGF_LEVELS,	"LEVELS" }, \
+	{ XFS_AGF_FLFIRST,	"FLFIRST" }, \
+	{ XFS_AGF_FLLAST,	"FLLAST" }, \
+	{ XFS_AGF_FLCOUNT,	"FLCOUNT" }, \
+	{ XFS_AGF_FREEBLKS,	"FREEBLKS" }, \
+	{ XFS_AGF_LONGEST,	"LONGEST" }, \
+	{ XFS_AGF_BTREEBLKS,	"BTREEBLKS" }, \
+	{ XFS_AGF_UUID,		"UUID" }
+
+/* disk block (xfs_daddr_t) in the AG */
+#define XFS_AGF_DADDR(mp)	((xfs_daddr_t)(1 << (mp)->m_sectbb_log))
+#define	XFS_AGF_BLOCK(mp)	XFS_HDR_BLOCK(mp, XFS_AGF_DADDR(mp))
+#define	XFS_BUF_TO_AGF(bp)	((xfs_agf_t *)((bp)->b_addr))
+
+/*
+ * Size of the unlinked inode hash table in the agi.
+ */
+#define	XFS_AGI_UNLINKED_BUCKETS	64
+
+typedef struct xfs_agi {
+	/*
+	 * Common allocation group header information
+	 */
+	__be32		agi_magicnum;	/* magic number == XFS_AGI_MAGIC */
+	__be32		agi_versionnum;	/* header version == XFS_AGI_VERSION */
+	__be32		agi_seqno;	/* sequence # starting from 0 */
+	__be32		agi_length;	/* size in blocks of a.g. */
+	/*
+	 * Inode information
+	 * Inodes are mapped by interpreting the inode number, so no
+	 * mapping data is needed here.
+	 */
+	__be32		agi_count;	/* count of allocated inodes */
+	__be32		agi_root;	/* root of inode btree */
+	__be32		agi_level;	/* levels in inode btree */
+	__be32		agi_freecount;	/* number of free inodes */
+
+	__be32		agi_newino;	/* new inode just allocated */
+	__be32		agi_dirino;	/* last directory inode chunk */
+	/*
+	 * Hash table of inodes which have been unlinked but are
+	 * still being referenced.
+	 */
+	__be32		agi_unlinked[XFS_AGI_UNLINKED_BUCKETS];
+	/*
+	 * This marks the end of logging region 1 and start of logging region 2.
+	 */
+	uuid_t		agi_uuid;	/* uuid of filesystem */
+	__be32		agi_crc;	/* crc of agi sector */
+	__be32		agi_pad32;
+	__be64		agi_lsn;	/* last write sequence */
+
+	__be32		agi_free_root; /* root of the free inode btree */
+	__be32		agi_free_level;/* levels in free inode btree */
+
+	/* structure must be padded to 64 bit alignment */
+} xfs_agi_t;
+
+#define XFS_AGI_CRC_OFF		offsetof(struct xfs_agi, agi_crc)
+
+#define	XFS_AGI_MAGICNUM	(1 << 0)
+#define	XFS_AGI_VERSIONNUM	(1 << 1)
+#define	XFS_AGI_SEQNO		(1 << 2)
+#define	XFS_AGI_LENGTH		(1 << 3)
+#define	XFS_AGI_COUNT		(1 << 4)
+#define	XFS_AGI_ROOT		(1 << 5)
+#define	XFS_AGI_LEVEL		(1 << 6)
+#define	XFS_AGI_FREECOUNT	(1 << 7)
+#define	XFS_AGI_NEWINO		(1 << 8)
+#define	XFS_AGI_DIRINO		(1 << 9)
+#define	XFS_AGI_UNLINKED	(1 << 10)
+#define	XFS_AGI_NUM_BITS_R1	11	/* end of the 1st agi logging region */
+#define	XFS_AGI_ALL_BITS_R1	((1 << XFS_AGI_NUM_BITS_R1) - 1)
+#define	XFS_AGI_FREE_ROOT	(1 << 11)
+#define	XFS_AGI_FREE_LEVEL	(1 << 12)
+#define	XFS_AGI_NUM_BITS_R2	13
+
+/* disk block (xfs_daddr_t) in the AG */
+#define XFS_AGI_DADDR(mp)	((xfs_daddr_t)(2 << (mp)->m_sectbb_log))
+#define	XFS_AGI_BLOCK(mp)	XFS_HDR_BLOCK(mp, XFS_AGI_DADDR(mp))
+#define	XFS_BUF_TO_AGI(bp)	((xfs_agi_t *)((bp)->b_addr))
+
+/*
+ * The third a.g. block contains the a.g. freelist, an array
+ * of block pointers to blocks owned by the allocation btree code.
+ */
+#define XFS_AGFL_DADDR(mp)	((xfs_daddr_t)(3 << (mp)->m_sectbb_log))
+#define	XFS_AGFL_BLOCK(mp)	XFS_HDR_BLOCK(mp, XFS_AGFL_DADDR(mp))
+#define	XFS_BUF_TO_AGFL(bp)	((xfs_agfl_t *)((bp)->b_addr))
+
+#define XFS_BUF_TO_AGFL_BNO(mp, bp) \
+	(xfs_sb_version_hascrc(&((mp)->m_sb)) ? \
+		&(XFS_BUF_TO_AGFL(bp)->agfl_bno[0]) : \
+		(__be32 *)(bp)->b_addr)
+
+/*
+ * Size of the AGFL.  For CRC-enabled filesystes we steal a couple of
+ * slots in the beginning of the block for a proper header with the
+ * location information and CRC.
+ */
+#define XFS_AGFL_SIZE(mp) \
+	(((mp)->m_sb.sb_sectsize - \
+	 (xfs_sb_version_hascrc(&((mp)->m_sb)) ? \
+		sizeof(struct xfs_agfl) : 0)) / \
+	  sizeof(xfs_agblock_t))
+
+typedef struct xfs_agfl {
+	__be32		agfl_magicnum;
+	__be32		agfl_seqno;
+	uuid_t		agfl_uuid;
+	__be64		agfl_lsn;
+	__be32		agfl_crc;
+	__be32		agfl_bno[];	/* actually XFS_AGFL_SIZE(mp) */
+} xfs_agfl_t;
+
+#define XFS_AGFL_CRC_OFF	offsetof(struct xfs_agfl, agfl_crc)
+
+
+#define	XFS_AG_MAXLEVELS(mp)		((mp)->m_ag_maxlevels)
+#define	XFS_MIN_FREELIST_RAW(bl,cl,mp)	\
+	(MIN(bl + 1, XFS_AG_MAXLEVELS(mp)) + MIN(cl + 1, XFS_AG_MAXLEVELS(mp)))
+#define	XFS_MIN_FREELIST(a,mp)		\
+	(XFS_MIN_FREELIST_RAW(		\
+		be32_to_cpu((a)->agf_levels[XFS_BTNUM_BNOi]), \
+		be32_to_cpu((a)->agf_levels[XFS_BTNUM_CNTi]), mp))
+#define	XFS_MIN_FREELIST_PAG(pag,mp)	\
+	(XFS_MIN_FREELIST_RAW(		\
+		(unsigned int)(pag)->pagf_levels[XFS_BTNUM_BNOi], \
+		(unsigned int)(pag)->pagf_levels[XFS_BTNUM_CNTi], mp))
+
+#define XFS_AGB_TO_FSB(mp,agno,agbno)	\
+	(((xfs_fsblock_t)(agno) << (mp)->m_sb.sb_agblklog) | (agbno))
+#define	XFS_FSB_TO_AGNO(mp,fsbno)	\
+	((xfs_agnumber_t)((fsbno) >> (mp)->m_sb.sb_agblklog))
+#define	XFS_FSB_TO_AGBNO(mp,fsbno)	\
+	((xfs_agblock_t)((fsbno) & xfs_mask32lo((mp)->m_sb.sb_agblklog)))
+#define	XFS_AGB_TO_DADDR(mp,agno,agbno)	\
+	((xfs_daddr_t)XFS_FSB_TO_BB(mp, \
+		(xfs_fsblock_t)(agno) * (mp)->m_sb.sb_agblocks + (agbno)))
+#define	XFS_AG_DADDR(mp,agno,d)		(XFS_AGB_TO_DADDR(mp, agno, 0) + (d))
+
+/*
+ * For checking for bad ranges of xfs_daddr_t's, covering multiple
+ * allocation groups or a single xfs_daddr_t that's a superblock copy.
+ */
+#define	XFS_AG_CHECK_DADDR(mp,d,len)	\
+	((len) == 1 ? \
+	    ASSERT((d) == XFS_SB_DADDR || \
+		   xfs_daddr_to_agbno(mp, d) != XFS_SB_DADDR) : \
+	    ASSERT(xfs_daddr_to_agno(mp, d) == \
+		   xfs_daddr_to_agno(mp, (d) + (len) - 1)))
+
 typedef struct xfs_timestamp {
 	__be32		t_sec;		/* timestamp seconds */
 	__be32		t_nsec;		/* timestamp nanoseconds */