From 035e00acb5c719bd003639b90716a7e94e023b73 Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Wed, 3 Aug 2016 11:36:07 +1000 Subject: xfs: define the on-disk rmap btree format Originally-From: Dave Chinner Now we have all the surrounding call infrastructure in place, we can start filling out the rmap btree implementation. Start with the on-disk btree format; add everything needed to read, write and manipulate rmap btree blocks. This prepares the way for adding the btree operations implementation. [darrick: record owner and offset info in rmap btree] [darrick: fork, bmbt and unwritten state in rmap btree] [darrick: flags are a separate field in xfs_rmap_irec] [darrick: calculate maxlevels separately] [darrick: move the 'unwritten' bit into unused parts of rm_offset] Signed-off-by: Dave Chinner Signed-off-by: Darrick J. Wong Reviewed-by: Dave Chinner Reviewed-by: Brian Foster Signed-off-by: Dave Chinner --- fs/xfs/libxfs/xfs_format.h | 73 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 73 insertions(+) (limited to 'fs/xfs/libxfs/xfs_format.h') diff --git a/fs/xfs/libxfs/xfs_format.h b/fs/xfs/libxfs/xfs_format.h index eecfedf19be5..f6a0641e64c8 100644 --- a/fs/xfs/libxfs/xfs_format.h +++ b/fs/xfs/libxfs/xfs_format.h @@ -1347,6 +1347,79 @@ struct xfs_owner_info { #define XFS_RMAP_OWN_INODES (-7ULL) /* Inode chunk */ #define XFS_RMAP_OWN_MIN (-8ULL) /* guard */ +#define XFS_RMAP_NON_INODE_OWNER(owner) (!!((owner) & (1ULL << 63))) + +/* + * Data record structure + */ +struct xfs_rmap_rec { + __be32 rm_startblock; /* extent start block */ + __be32 rm_blockcount; /* extent length */ + __be64 rm_owner; /* extent owner */ + __be64 rm_offset; /* offset within the owner */ +}; + +/* + * rmap btree record + * rm_offset:63 is the attribute fork flag + * rm_offset:62 is the bmbt block flag + * rm_offset:61 is the unwritten extent flag (same as l0:63 in bmbt) + * rm_offset:54-60 aren't used and should be zero + * rm_offset:0-53 is the block offset within the inode + */ +#define XFS_RMAP_OFF_ATTR_FORK ((__uint64_t)1ULL << 63) +#define XFS_RMAP_OFF_BMBT_BLOCK ((__uint64_t)1ULL << 62) +#define XFS_RMAP_OFF_UNWRITTEN ((__uint64_t)1ULL << 61) + +#define XFS_RMAP_LEN_MAX ((__uint32_t)~0U) +#define XFS_RMAP_OFF_FLAGS (XFS_RMAP_OFF_ATTR_FORK | \ + XFS_RMAP_OFF_BMBT_BLOCK | \ + XFS_RMAP_OFF_UNWRITTEN) +#define XFS_RMAP_OFF_MASK ((__uint64_t)0x3FFFFFFFFFFFFFULL) + +#define XFS_RMAP_OFF(off) ((off) & XFS_RMAP_OFF_MASK) + +#define XFS_RMAP_IS_BMBT_BLOCK(off) (!!((off) & XFS_RMAP_OFF_BMBT_BLOCK)) +#define XFS_RMAP_IS_ATTR_FORK(off) (!!((off) & XFS_RMAP_OFF_ATTR_FORK)) +#define XFS_RMAP_IS_UNWRITTEN(len) (!!((off) & XFS_RMAP_OFF_UNWRITTEN)) + +#define RMAPBT_STARTBLOCK_BITLEN 32 +#define RMAPBT_BLOCKCOUNT_BITLEN 32 +#define RMAPBT_OWNER_BITLEN 64 +#define RMAPBT_ATTRFLAG_BITLEN 1 +#define RMAPBT_BMBTFLAG_BITLEN 1 +#define RMAPBT_EXNTFLAG_BITLEN 1 +#define RMAPBT_UNUSED_OFFSET_BITLEN 7 +#define RMAPBT_OFFSET_BITLEN 54 + +#define XFS_RMAP_ATTR_FORK (1 << 0) +#define XFS_RMAP_BMBT_BLOCK (1 << 1) +#define XFS_RMAP_UNWRITTEN (1 << 2) +#define XFS_RMAP_KEY_FLAGS (XFS_RMAP_ATTR_FORK | \ + XFS_RMAP_BMBT_BLOCK) +#define XFS_RMAP_REC_FLAGS (XFS_RMAP_UNWRITTEN) +struct xfs_rmap_irec { + xfs_agblock_t rm_startblock; /* extent start block */ + xfs_extlen_t rm_blockcount; /* extent length */ + __uint64_t rm_owner; /* extent owner */ + __uint64_t rm_offset; /* offset within the owner */ + unsigned int rm_flags; /* state flags */ +}; + +/* + * Key structure + * + * We don't use the length for lookups + */ +struct xfs_rmap_key { + __be32 rm_startblock; /* extent start block */ + __be64 rm_owner; /* extent owner */ + __be64 rm_offset; /* offset within the owner */ +} __attribute__((packed)); + +/* btree pointer type */ +typedef __be32 xfs_rmap_ptr_t; + #define XFS_RMAP_BLOCK(mp) \ (xfs_sb_version_hasfinobt(&((mp)->m_sb)) ? \ XFS_FIBT_BLOCK(mp) + 1 : \ -- cgit v1.2.3