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diff --git a/fs/xfs/libxfs/xfs_format.h b/fs/xfs/libxfs/xfs_format.h
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+++ b/fs/xfs/libxfs/xfs_format.h
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+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (c) 2000-2005 Silicon Graphics, Inc.
+ * All Rights Reserved.
+ */
+#ifndef __XFS_FORMAT_H__
+#define __XFS_FORMAT_H__
+
+/*
+ * XFS On Disk Format Definitions
+ *
+ * This header file defines all the on-disk format definitions for
+ * general XFS objects. Directory and attribute related objects are defined in
+ * xfs_da_format.h, which log and log item formats are defined in
+ * xfs_log_format.h. Everything else goes here.
+ */
+
+struct xfs_mount;
+struct xfs_trans;
+struct xfs_inode;
+struct xfs_buf;
+struct xfs_ifork;
+
+/*
+ * Super block
+ * Fits into a sector-sized buffer at address 0 of each allocation group.
+ * Only the first of these is ever updated except during growfs.
+ */
+#define XFS_SB_MAGIC 0x58465342 /* 'XFSB' */
+#define XFS_SB_VERSION_1 1 /* 5.3, 6.0.1, 6.1 */
+#define XFS_SB_VERSION_2 2 /* 6.2 - attributes */
+#define XFS_SB_VERSION_3 3 /* 6.2 - new inode version */
+#define XFS_SB_VERSION_4 4 /* 6.2+ - bitmask version */
+#define XFS_SB_VERSION_5 5 /* CRC enabled filesystem */
+#define XFS_SB_VERSION_NUMBITS 0x000f
+#define XFS_SB_VERSION_ALLFBITS 0xfff0
+#define XFS_SB_VERSION_ATTRBIT 0x0010
+#define XFS_SB_VERSION_NLINKBIT 0x0020
+#define XFS_SB_VERSION_QUOTABIT 0x0040
+#define XFS_SB_VERSION_ALIGNBIT 0x0080
+#define XFS_SB_VERSION_DALIGNBIT 0x0100
+#define XFS_SB_VERSION_SHAREDBIT 0x0200
+#define XFS_SB_VERSION_LOGV2BIT 0x0400
+#define XFS_SB_VERSION_SECTORBIT 0x0800
+#define XFS_SB_VERSION_EXTFLGBIT 0x1000
+#define XFS_SB_VERSION_DIRV2BIT 0x2000
+#define XFS_SB_VERSION_BORGBIT 0x4000 /* ASCII only case-insens. */
+#define XFS_SB_VERSION_MOREBITSBIT 0x8000
+
+/*
+ * The size of a single extended attribute on disk is limited by
+ * the size of index values within the attribute entries themselves.
+ * These are be16 fields, so we can only support attribute data
+ * sizes up to 2^16 bytes in length.
+ */
+#define XFS_XATTR_SIZE_MAX (1 << 16)
+
+/*
+ * Supported feature bit list is just all bits in the versionnum field because
+ * we've used them all up and understand them all. Except, of course, for the
+ * shared superblock bit, which nobody knows what it does and so is unsupported.
+ */
+#define XFS_SB_VERSION_OKBITS \
+ ((XFS_SB_VERSION_NUMBITS | XFS_SB_VERSION_ALLFBITS) & \
+ ~XFS_SB_VERSION_SHAREDBIT)
+
+/*
+ * There are two words to hold XFS "feature" bits: the original
+ * word, sb_versionnum, and sb_features2. Whenever a bit is set in
+ * sb_features2, the feature bit XFS_SB_VERSION_MOREBITSBIT must be set.
+ *
+ * These defines represent bits in sb_features2.
+ */
+#define XFS_SB_VERSION2_RESERVED1BIT 0x00000001
+#define XFS_SB_VERSION2_LAZYSBCOUNTBIT 0x00000002 /* Superblk counters */
+#define XFS_SB_VERSION2_RESERVED4BIT 0x00000004
+#define XFS_SB_VERSION2_ATTR2BIT 0x00000008 /* Inline attr rework */
+#define XFS_SB_VERSION2_PARENTBIT 0x00000010 /* parent pointers */
+#define XFS_SB_VERSION2_PROJID32BIT 0x00000080 /* 32 bit project id */
+#define XFS_SB_VERSION2_CRCBIT 0x00000100 /* metadata CRCs */
+#define XFS_SB_VERSION2_FTYPE 0x00000200 /* inode type in dir */
+
+#define XFS_SB_VERSION2_OKBITS \
+ (XFS_SB_VERSION2_LAZYSBCOUNTBIT | \
+ XFS_SB_VERSION2_ATTR2BIT | \
+ XFS_SB_VERSION2_PROJID32BIT | \
+ XFS_SB_VERSION2_FTYPE)
+
+/* Maximum size of the xfs filesystem label, no terminating NULL */
+#define XFSLABEL_MAX 12
+
+/*
+ * Superblock - in core version. Must match the ondisk version below.
+ * Must be padded to 64 bit alignment.
+ */
+typedef struct xfs_sb {
+ uint32_t sb_magicnum; /* magic number == XFS_SB_MAGIC */
+ uint32_t sb_blocksize; /* logical block size, bytes */
+ xfs_rfsblock_t sb_dblocks; /* number of data blocks */
+ xfs_rfsblock_t sb_rblocks; /* number of realtime blocks */
+ xfs_rtblock_t sb_rextents; /* number of realtime extents */
+ uuid_t sb_uuid; /* user-visible file system unique id */
+ xfs_fsblock_t sb_logstart; /* starting block of log if internal */
+ xfs_ino_t sb_rootino; /* root inode number */
+ xfs_ino_t sb_rbmino; /* bitmap inode for realtime extents */
+ xfs_ino_t sb_rsumino; /* summary inode for rt bitmap */
+ xfs_agblock_t sb_rextsize; /* realtime extent size, blocks */
+ xfs_agblock_t sb_agblocks; /* size of an allocation group */
+ xfs_agnumber_t sb_agcount; /* number of allocation groups */
+ xfs_extlen_t sb_rbmblocks; /* number of rt bitmap blocks */
+ xfs_extlen_t sb_logblocks; /* number of log blocks */
+ uint16_t sb_versionnum; /* header version == XFS_SB_VERSION */
+ uint16_t sb_sectsize; /* volume sector size, bytes */
+ uint16_t sb_inodesize; /* inode size, bytes */
+ uint16_t sb_inopblock; /* inodes per block */
+ char sb_fname[XFSLABEL_MAX]; /* file system name */
+ uint8_t sb_blocklog; /* log2 of sb_blocksize */
+ uint8_t sb_sectlog; /* log2 of sb_sectsize */
+ uint8_t sb_inodelog; /* log2 of sb_inodesize */
+ uint8_t sb_inopblog; /* log2 of sb_inopblock */
+ uint8_t sb_agblklog; /* log2 of sb_agblocks (rounded up) */
+ uint8_t sb_rextslog; /* log2 of sb_rextents */
+ uint8_t sb_inprogress; /* mkfs is in progress, don't mount */
+ uint8_t sb_imax_pct; /* max % of fs for inode space */
+ /* statistics */
+ /*
+ * These fields must remain contiguous. If you really
+ * want to change their layout, make sure you fix the
+ * code in xfs_trans_apply_sb_deltas().
+ */
+ uint64_t sb_icount; /* allocated inodes */
+ uint64_t sb_ifree; /* free inodes */
+ uint64_t sb_fdblocks; /* free data blocks */
+ uint64_t sb_frextents; /* free realtime extents */
+ /*
+ * End contiguous fields.
+ */
+ xfs_ino_t sb_uquotino; /* user quota inode */
+ xfs_ino_t sb_gquotino; /* group quota inode */
+ uint16_t sb_qflags; /* quota flags */
+ uint8_t sb_flags; /* misc. flags */
+ uint8_t sb_shared_vn; /* shared version number */
+ xfs_extlen_t sb_inoalignmt; /* inode chunk alignment, fsblocks */
+ uint32_t sb_unit; /* stripe or raid unit */
+ uint32_t sb_width; /* stripe or raid width */
+ uint8_t sb_dirblklog; /* log2 of dir block size (fsbs) */
+ uint8_t sb_logsectlog; /* log2 of the log sector size */
+ uint16_t sb_logsectsize; /* sector size for the log, bytes */
+ uint32_t sb_logsunit; /* stripe unit size for the log */
+ uint32_t sb_features2; /* additional feature bits */
+
+ /*
+ * bad features2 field as a result of failing to pad the sb structure to
+ * 64 bits. Some machines will be using this field for features2 bits.
+ * Easiest just to mark it bad and not use it for anything else.
+ *
+ * This is not kept up to date in memory; it is always overwritten by
+ * the value in sb_features2 when formatting the incore superblock to
+ * the disk buffer.
+ */
+ uint32_t sb_bad_features2;
+
+ /* version 5 superblock fields start here */
+
+ /* feature masks */
+ uint32_t sb_features_compat;
+ uint32_t sb_features_ro_compat;
+ uint32_t sb_features_incompat;
+ uint32_t sb_features_log_incompat;
+
+ uint32_t sb_crc; /* superblock crc */
+ xfs_extlen_t sb_spino_align; /* sparse inode chunk alignment */
+
+ xfs_ino_t sb_pquotino; /* project quota inode */
+ xfs_lsn_t sb_lsn; /* last write sequence */
+ uuid_t sb_meta_uuid; /* metadata file system unique id */
+
+ /* must be padded to 64 bit alignment */
+} xfs_sb_t;
+
+#define XFS_SB_CRC_OFF offsetof(struct xfs_sb, sb_crc)
+
+/*
+ * Superblock - on disk version. Must match the in core version above.
+ * Must be padded to 64 bit alignment.
+ */
+struct xfs_dsb {
+ __be32 sb_magicnum; /* magic number == XFS_SB_MAGIC */
+ __be32 sb_blocksize; /* logical block size, bytes */
+ __be64 sb_dblocks; /* number of data blocks */
+ __be64 sb_rblocks; /* number of realtime blocks */
+ __be64 sb_rextents; /* number of realtime extents */
+ uuid_t sb_uuid; /* user-visible file system unique id */
+ __be64 sb_logstart; /* starting block of log if internal */
+ __be64 sb_rootino; /* root inode number */
+ __be64 sb_rbmino; /* bitmap inode for realtime extents */
+ __be64 sb_rsumino; /* summary inode for rt bitmap */
+ __be32 sb_rextsize; /* realtime extent size, blocks */
+ __be32 sb_agblocks; /* size of an allocation group */
+ __be32 sb_agcount; /* number of allocation groups */
+ __be32 sb_rbmblocks; /* number of rt bitmap blocks */
+ __be32 sb_logblocks; /* number of log blocks */
+ __be16 sb_versionnum; /* header version == XFS_SB_VERSION */
+ __be16 sb_sectsize; /* volume sector size, bytes */
+ __be16 sb_inodesize; /* inode size, bytes */
+ __be16 sb_inopblock; /* inodes per block */
+ char sb_fname[XFSLABEL_MAX]; /* file system name */
+ __u8 sb_blocklog; /* log2 of sb_blocksize */
+ __u8 sb_sectlog; /* log2 of sb_sectsize */
+ __u8 sb_inodelog; /* log2 of sb_inodesize */
+ __u8 sb_inopblog; /* log2 of sb_inopblock */
+ __u8 sb_agblklog; /* log2 of sb_agblocks (rounded up) */
+ __u8 sb_rextslog; /* log2 of sb_rextents */
+ __u8 sb_inprogress; /* mkfs is in progress, don't mount */
+ __u8 sb_imax_pct; /* max % of fs for inode space */
+ /* statistics */
+ /*
+ * These fields must remain contiguous. If you really
+ * want to change their layout, make sure you fix the
+ * code in xfs_trans_apply_sb_deltas().
+ */
+ __be64 sb_icount; /* allocated inodes */
+ __be64 sb_ifree; /* free inodes */
+ __be64 sb_fdblocks; /* free data blocks */
+ __be64 sb_frextents; /* free realtime extents */
+ /*
+ * End contiguous fields.
+ */
+ __be64 sb_uquotino; /* user quota inode */
+ __be64 sb_gquotino; /* group quota inode */
+ __be16 sb_qflags; /* quota flags */
+ __u8 sb_flags; /* misc. flags */
+ __u8 sb_shared_vn; /* shared version number */
+ __be32 sb_inoalignmt; /* inode chunk alignment, fsblocks */
+ __be32 sb_unit; /* stripe or raid unit */
+ __be32 sb_width; /* stripe or raid width */
+ __u8 sb_dirblklog; /* log2 of dir block size (fsbs) */
+ __u8 sb_logsectlog; /* log2 of the log sector size */
+ __be16 sb_logsectsize; /* sector size for the log, bytes */
+ __be32 sb_logsunit; /* stripe unit size for the log */
+ __be32 sb_features2; /* additional feature bits */
+ /*
+ * bad features2 field as a result of failing to pad the sb
+ * structure to 64 bits. Some machines will be using this field
+ * for features2 bits. Easiest just to mark it bad and not use
+ * it for anything else.
+ */
+ __be32 sb_bad_features2;
+
+ /* version 5 superblock fields start here */
+
+ /* feature masks */
+ __be32 sb_features_compat;
+ __be32 sb_features_ro_compat;
+ __be32 sb_features_incompat;
+ __be32 sb_features_log_incompat;
+
+ __le32 sb_crc; /* superblock crc */
+ __be32 sb_spino_align; /* sparse inode chunk alignment */
+
+ __be64 sb_pquotino; /* project quota inode */
+ __be64 sb_lsn; /* last write sequence */
+ uuid_t sb_meta_uuid; /* metadata file system unique id */
+
+ /* must be padded to 64 bit alignment */
+};
+
+/*
+ * Misc. Flags - warning - these will be cleared by xfs_repair unless
+ * a feature bit is set when the flag is used.
+ */
+#define XFS_SBF_NOFLAGS 0x00 /* no flags set */
+#define XFS_SBF_READONLY 0x01 /* only read-only mounts allowed */
+
+/*
+ * define max. shared version we can interoperate with
+ */
+#define XFS_SB_MAX_SHARED_VN 0
+
+#define XFS_SB_VERSION_NUM(sbp) ((sbp)->sb_versionnum & XFS_SB_VERSION_NUMBITS)
+
+static inline bool xfs_sb_is_v5(struct xfs_sb *sbp)
+{
+ return XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5;
+}
+
+/*
+ * Detect a mismatched features2 field. Older kernels read/wrote
+ * this into the wrong slot, so to be safe we keep them in sync.
+ */
+static inline bool xfs_sb_has_mismatched_features2(struct xfs_sb *sbp)
+{
+ return sbp->sb_bad_features2 != sbp->sb_features2;
+}
+
+static inline bool xfs_sb_version_hasmorebits(struct xfs_sb *sbp)
+{
+ return xfs_sb_is_v5(sbp) ||
+ (sbp->sb_versionnum & XFS_SB_VERSION_MOREBITSBIT);
+}
+
+static inline void xfs_sb_version_addattr(struct xfs_sb *sbp)
+{
+ sbp->sb_versionnum |= XFS_SB_VERSION_ATTRBIT;
+}
+
+static inline void xfs_sb_version_addquota(struct xfs_sb *sbp)
+{
+ sbp->sb_versionnum |= XFS_SB_VERSION_QUOTABIT;
+}
+
+static inline void xfs_sb_version_addattr2(struct xfs_sb *sbp)
+{
+ sbp->sb_versionnum |= XFS_SB_VERSION_MOREBITSBIT;
+ sbp->sb_features2 |= XFS_SB_VERSION2_ATTR2BIT;
+}
+
+static inline void xfs_sb_version_addprojid32(struct xfs_sb *sbp)
+{
+ sbp->sb_versionnum |= XFS_SB_VERSION_MOREBITSBIT;
+ sbp->sb_features2 |= XFS_SB_VERSION2_PROJID32BIT;
+}
+
+/*
+ * Extended v5 superblock feature masks. These are to be used for new v5
+ * superblock features only.
+ *
+ * Compat features are new features that old kernels will not notice or affect
+ * and so can mount read-write without issues.
+ *
+ * RO-Compat (read only) are features that old kernels can read but will break
+ * if they write. Hence only read-only mounts of such filesystems are allowed on
+ * kernels that don't support the feature bit.
+ *
+ * InCompat features are features which old kernels will not understand and so
+ * must not mount.
+ *
+ * Log-InCompat features are for changes to log formats or new transactions that
+ * can't be replayed on older kernels. The fields are set when the filesystem is
+ * mounted, and a clean unmount clears the fields.
+ */
+#define XFS_SB_FEAT_COMPAT_ALL 0
+#define XFS_SB_FEAT_COMPAT_UNKNOWN ~XFS_SB_FEAT_COMPAT_ALL
+static inline bool
+xfs_sb_has_compat_feature(
+ struct xfs_sb *sbp,
+ uint32_t feature)
+{
+ return (sbp->sb_features_compat & feature) != 0;
+}
+
+#define XFS_SB_FEAT_RO_COMPAT_FINOBT (1 << 0) /* free inode btree */
+#define XFS_SB_FEAT_RO_COMPAT_RMAPBT (1 << 1) /* reverse map btree */
+#define XFS_SB_FEAT_RO_COMPAT_REFLINK (1 << 2) /* reflinked files */
+#define XFS_SB_FEAT_RO_COMPAT_INOBTCNT (1 << 3) /* inobt block counts */
+#define XFS_SB_FEAT_RO_COMPAT_ALL \
+ (XFS_SB_FEAT_RO_COMPAT_FINOBT | \
+ XFS_SB_FEAT_RO_COMPAT_RMAPBT | \
+ XFS_SB_FEAT_RO_COMPAT_REFLINK| \
+ XFS_SB_FEAT_RO_COMPAT_INOBTCNT)
+#define XFS_SB_FEAT_RO_COMPAT_UNKNOWN ~XFS_SB_FEAT_RO_COMPAT_ALL
+static inline bool
+xfs_sb_has_ro_compat_feature(
+ struct xfs_sb *sbp,
+ uint32_t feature)
+{
+ return (sbp->sb_features_ro_compat & feature) != 0;
+}
+
+#define XFS_SB_FEAT_INCOMPAT_FTYPE (1 << 0) /* filetype in dirent */
+#define XFS_SB_FEAT_INCOMPAT_SPINODES (1 << 1) /* sparse inode chunks */
+#define XFS_SB_FEAT_INCOMPAT_META_UUID (1 << 2) /* metadata UUID */
+#define XFS_SB_FEAT_INCOMPAT_BIGTIME (1 << 3) /* large timestamps */
+#define XFS_SB_FEAT_INCOMPAT_NEEDSREPAIR (1 << 4) /* needs xfs_repair */
+#define XFS_SB_FEAT_INCOMPAT_NREXT64 (1 << 5) /* large extent counters */
+#define XFS_SB_FEAT_INCOMPAT_ALL \
+ (XFS_SB_FEAT_INCOMPAT_FTYPE| \
+ XFS_SB_FEAT_INCOMPAT_SPINODES| \
+ XFS_SB_FEAT_INCOMPAT_META_UUID| \
+ XFS_SB_FEAT_INCOMPAT_BIGTIME| \
+ XFS_SB_FEAT_INCOMPAT_NEEDSREPAIR| \
+ XFS_SB_FEAT_INCOMPAT_NREXT64)
+
+#define XFS_SB_FEAT_INCOMPAT_UNKNOWN ~XFS_SB_FEAT_INCOMPAT_ALL
+static inline bool
+xfs_sb_has_incompat_feature(
+ struct xfs_sb *sbp,
+ uint32_t feature)
+{
+ return (sbp->sb_features_incompat & feature) != 0;
+}
+
+#define XFS_SB_FEAT_INCOMPAT_LOG_XATTRS (1 << 0) /* Delayed Attributes */
+#define XFS_SB_FEAT_INCOMPAT_LOG_ALL \
+ (XFS_SB_FEAT_INCOMPAT_LOG_XATTRS)
+#define XFS_SB_FEAT_INCOMPAT_LOG_UNKNOWN ~XFS_SB_FEAT_INCOMPAT_LOG_ALL
+static inline bool
+xfs_sb_has_incompat_log_feature(
+ struct xfs_sb *sbp,
+ uint32_t feature)
+{
+ return (sbp->sb_features_log_incompat & feature) != 0;
+}
+
+static inline void
+xfs_sb_remove_incompat_log_features(
+ struct xfs_sb *sbp)
+{
+ sbp->sb_features_log_incompat &= ~XFS_SB_FEAT_INCOMPAT_LOG_ALL;
+}
+
+static inline void
+xfs_sb_add_incompat_log_features(
+ struct xfs_sb *sbp,
+ unsigned int features)
+{
+ sbp->sb_features_log_incompat |= features;
+}
+
+static inline bool xfs_sb_version_haslogxattrs(struct xfs_sb *sbp)
+{
+ return xfs_sb_is_v5(sbp) && (sbp->sb_features_log_incompat &
+ XFS_SB_FEAT_INCOMPAT_LOG_XATTRS);
+}
+
+static inline bool
+xfs_is_quota_inode(struct xfs_sb *sbp, xfs_ino_t ino)
+{
+ return (ino == sbp->sb_uquotino ||
+ ino == sbp->sb_gquotino ||
+ ino == sbp->sb_pquotino);
+}
+
+#define XFS_SB_DADDR ((xfs_daddr_t)0) /* daddr in filesystem/ag */
+#define XFS_SB_BLOCK(mp) XFS_HDR_BLOCK(mp, XFS_SB_DADDR)
+
+#define XFS_HDR_BLOCK(mp,d) ((xfs_agblock_t)XFS_BB_TO_FSBT(mp,d))
+#define XFS_DADDR_TO_FSB(mp,d) XFS_AGB_TO_FSB(mp, \
+ xfs_daddr_to_agno(mp,d), xfs_daddr_to_agbno(mp,d))
+#define XFS_FSB_TO_DADDR(mp,fsbno) XFS_AGB_TO_DADDR(mp, \
+ XFS_FSB_TO_AGNO(mp,fsbno), XFS_FSB_TO_AGBNO(mp,fsbno))
+
+/*
+ * File system sector to basic block conversions.
+ */
+#define XFS_FSS_TO_BB(mp,sec) ((sec) << (mp)->m_sectbb_log)
+
+/*
+ * File system block to basic block conversions.
+ */
+#define XFS_FSB_TO_BB(mp,fsbno) ((fsbno) << (mp)->m_blkbb_log)
+#define XFS_BB_TO_FSB(mp,bb) \
+ (((bb) + (XFS_FSB_TO_BB(mp,1) - 1)) >> (mp)->m_blkbb_log)
+#define XFS_BB_TO_FSBT(mp,bb) ((bb) >> (mp)->m_blkbb_log)
+
+/*
+ * File system block to byte conversions.
+ */
+#define XFS_FSB_TO_B(mp,fsbno) ((xfs_fsize_t)(fsbno) << (mp)->m_sb.sb_blocklog)
+#define XFS_B_TO_FSB(mp,b) \
+ ((((uint64_t)(b)) + (mp)->m_blockmask) >> (mp)->m_sb.sb_blocklog)
+#define XFS_B_TO_FSBT(mp,b) (((uint64_t)(b)) >> (mp)->m_sb.sb_blocklog)
+
+/*
+ * 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, 2 is rmap. This value gives the size of the
+ * arrays below.
+ */
+#define XFS_BTNUM_AGF ((int)XFS_BTNUM_RMAPi + 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 and rmap information
+ */
+ __be32 agf_roots[XFS_BTNUM_AGF]; /* root blocks */
+ __be32 agf_levels[XFS_BTNUM_AGF]; /* btree levels */
+
+ __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 */
+
+ __be32 agf_rmap_blocks; /* rmapbt blocks used */
+ __be32 agf_refcount_blocks; /* refcountbt blocks used */
+
+ __be32 agf_refcount_root; /* refcount tree root block */
+ __be32 agf_refcount_level; /* refcount btree levels */
+
+ /*
+ * 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[14];
+
+ /* 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 (1u << 0)
+#define XFS_AGF_VERSIONNUM (1u << 1)
+#define XFS_AGF_SEQNO (1u << 2)
+#define XFS_AGF_LENGTH (1u << 3)
+#define XFS_AGF_ROOTS (1u << 4)
+#define XFS_AGF_LEVELS (1u << 5)
+#define XFS_AGF_FLFIRST (1u << 6)
+#define XFS_AGF_FLLAST (1u << 7)
+#define XFS_AGF_FLCOUNT (1u << 8)
+#define XFS_AGF_FREEBLKS (1u << 9)
+#define XFS_AGF_LONGEST (1u << 10)
+#define XFS_AGF_BTREEBLKS (1u << 11)
+#define XFS_AGF_UUID (1u << 12)
+#define XFS_AGF_RMAP_BLOCKS (1u << 13)
+#define XFS_AGF_REFCOUNT_BLOCKS (1u << 14)
+#define XFS_AGF_REFCOUNT_ROOT (1u << 15)
+#define XFS_AGF_REFCOUNT_LEVEL (1u << 16)
+#define XFS_AGF_SPARE64 (1u << 17)
+#define XFS_AGF_NUM_BITS 18
+#define XFS_AGF_ALL_BITS ((1u << 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" }, \
+ { XFS_AGF_RMAP_BLOCKS, "RMAP_BLOCKS" }, \
+ { XFS_AGF_REFCOUNT_BLOCKS, "REFCOUNT_BLOCKS" }, \
+ { XFS_AGF_REFCOUNT_ROOT, "REFCOUNT_ROOT" }, \
+ { XFS_AGF_REFCOUNT_LEVEL, "REFCOUNT_LEVEL" }, \
+ { XFS_AGF_SPARE64, "SPARE64" }
+
+/* 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))
+
+/*
+ * 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 */
+
+ __be32 agi_iblocks; /* inobt blocks used */
+ __be32 agi_fblocks; /* finobt blocks used */
+
+ /* 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 (1u << 0)
+#define XFS_AGI_VERSIONNUM (1u << 1)
+#define XFS_AGI_SEQNO (1u << 2)
+#define XFS_AGI_LENGTH (1u << 3)
+#define XFS_AGI_COUNT (1u << 4)
+#define XFS_AGI_ROOT (1u << 5)
+#define XFS_AGI_LEVEL (1u << 6)
+#define XFS_AGI_FREECOUNT (1u << 7)
+#define XFS_AGI_NEWINO (1u << 8)
+#define XFS_AGI_DIRINO (1u << 9)
+#define XFS_AGI_UNLINKED (1u << 10)
+#define XFS_AGI_NUM_BITS_R1 11 /* end of the 1st agi logging region */
+#define XFS_AGI_ALL_BITS_R1 ((1u << XFS_AGI_NUM_BITS_R1) - 1)
+#define XFS_AGI_FREE_ROOT (1u << 11)
+#define XFS_AGI_FREE_LEVEL (1u << 12)
+#define XFS_AGI_IBLOCKS (1u << 13) /* both inobt/finobt block counters */
+#define XFS_AGI_NUM_BITS_R2 14
+
+/* 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))
+
+/*
+ * 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) ((struct xfs_agfl *)((bp)->b_addr))
+
+struct xfs_agfl {
+ __be32 agfl_magicnum;
+ __be32 agfl_seqno;
+ uuid_t agfl_uuid;
+ __be64 agfl_lsn;
+ __be32 agfl_crc;
+} __attribute__((packed));
+
+#define XFS_AGFL_CRC_OFF offsetof(struct xfs_agfl, agfl_crc)
+
+#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)))
+
+/*
+ * XFS Timestamps
+ * ==============
+ *
+ * Traditional ondisk inode timestamps consist of signed 32-bit counters for
+ * seconds and nanoseconds; time zero is the Unix epoch, Jan 1 00:00:00 UTC
+ * 1970, which means that the timestamp epoch is the same as the Unix epoch.
+ * Therefore, the ondisk min and max defined here can be used directly to
+ * constrain the incore timestamps on a Unix system. Note that we actually
+ * encode a __be64 value on disk.
+ *
+ * When the bigtime feature is enabled, ondisk inode timestamps become an
+ * unsigned 64-bit nanoseconds counter. This means that the bigtime inode
+ * timestamp epoch is the start of the classic timestamp range, which is
+ * Dec 13 20:45:52 UTC 1901. Because the epochs are not the same, callers
+ * /must/ use the bigtime conversion functions when encoding and decoding raw
+ * timestamps.
+ */
+typedef __be64 xfs_timestamp_t;
+
+/* Legacy timestamp encoding format. */
+struct xfs_legacy_timestamp {
+ __be32 t_sec; /* timestamp seconds */
+ __be32 t_nsec; /* timestamp nanoseconds */
+};
+
+/*
+ * Smallest possible ondisk seconds value with traditional timestamps. This
+ * corresponds exactly with the incore timestamp Dec 13 20:45:52 UTC 1901.
+ */
+#define XFS_LEGACY_TIME_MIN ((int64_t)S32_MIN)
+
+/*
+ * Largest possible ondisk seconds value with traditional timestamps. This
+ * corresponds exactly with the incore timestamp Jan 19 03:14:07 UTC 2038.
+ */
+#define XFS_LEGACY_TIME_MAX ((int64_t)S32_MAX)
+
+/*
+ * Smallest possible ondisk seconds value with bigtime timestamps. This
+ * corresponds (after conversion to a Unix timestamp) with the traditional
+ * minimum timestamp of Dec 13 20:45:52 UTC 1901.
+ */
+#define XFS_BIGTIME_TIME_MIN ((int64_t)0)
+
+/*
+ * Largest supported ondisk seconds value with bigtime timestamps. This
+ * corresponds (after conversion to a Unix timestamp) with an incore timestamp
+ * of Jul 2 20:20:24 UTC 2486.
+ *
+ * We round down the ondisk limit so that the bigtime quota and inode max
+ * timestamps will be the same.
+ */
+#define XFS_BIGTIME_TIME_MAX ((int64_t)((-1ULL / NSEC_PER_SEC) & ~0x3ULL))
+
+/*
+ * Bigtime epoch is set exactly to the minimum time value that a traditional
+ * 32-bit timestamp can represent when using the Unix epoch as a reference.
+ * Hence the Unix epoch is at a fixed offset into the supported bigtime
+ * timestamp range.
+ *
+ * The bigtime epoch also matches the minimum value an on-disk 32-bit XFS
+ * timestamp can represent so we will not lose any fidelity in converting
+ * to/from unix and bigtime timestamps.
+ *
+ * The following conversion factor converts a seconds counter from the Unix
+ * epoch to the bigtime epoch.
+ */
+#define XFS_BIGTIME_EPOCH_OFFSET (-(int64_t)S32_MIN)
+
+/* Convert a timestamp from the Unix epoch to the bigtime epoch. */
+static inline uint64_t xfs_unix_to_bigtime(time64_t unix_seconds)
+{
+ return (uint64_t)unix_seconds + XFS_BIGTIME_EPOCH_OFFSET;
+}
+
+/* Convert a timestamp from the bigtime epoch to the Unix epoch. */
+static inline time64_t xfs_bigtime_to_unix(uint64_t ondisk_seconds)
+{
+ return (time64_t)ondisk_seconds - XFS_BIGTIME_EPOCH_OFFSET;
+}
+
+/*
+ * On-disk inode structure.
+ *
+ * This is just the header or "dinode core", the inode is expanded to fill a
+ * variable size the leftover area split into a data and an attribute fork.
+ * The format of the data and attribute fork depends on the format of the
+ * inode as indicated by di_format and di_aformat. To access the data and
+ * attribute use the XFS_DFORK_DPTR, XFS_DFORK_APTR, and XFS_DFORK_PTR macros
+ * below.
+ *
+ * There is a very similar struct xfs_log_dinode which matches the layout of
+ * this structure, but is kept in native format instead of big endian.
+ *
+ * Note: di_flushiter is only used by v1/2 inodes - it's effectively a zeroed
+ * padding field for v3 inodes.
+ */
+#define XFS_DINODE_MAGIC 0x494e /* 'IN' */
+struct xfs_dinode {
+ __be16 di_magic; /* inode magic # = XFS_DINODE_MAGIC */
+ __be16 di_mode; /* mode and type of file */
+ __u8 di_version; /* inode version */
+ __u8 di_format; /* format of di_c data */
+ __be16 di_onlink; /* old number of links to file */
+ __be32 di_uid; /* owner's user id */
+ __be32 di_gid; /* owner's group id */
+ __be32 di_nlink; /* number of links to file */
+ __be16 di_projid_lo; /* lower part of owner's project id */
+ __be16 di_projid_hi; /* higher part owner's project id */
+ union {
+ /* Number of data fork extents if NREXT64 is set */
+ __be64 di_big_nextents;
+
+ /* Padding for V3 inodes without NREXT64 set. */
+ __be64 di_v3_pad;
+
+ /* Padding and inode flush counter for V2 inodes. */
+ struct {
+ __u8 di_v2_pad[6];
+ __be16 di_flushiter;
+ };
+ };
+ xfs_timestamp_t di_atime; /* time last accessed */
+ xfs_timestamp_t di_mtime; /* time last modified */
+ xfs_timestamp_t di_ctime; /* time created/inode modified */
+ __be64 di_size; /* number of bytes in file */
+ __be64 di_nblocks; /* # of direct & btree blocks used */
+ __be32 di_extsize; /* basic/minimum extent size for file */
+ union {
+ /*
+ * For V2 inodes and V3 inodes without NREXT64 set, this
+ * is the number of data and attr fork extents.
+ */
+ struct {
+ __be32 di_nextents;
+ __be16 di_anextents;
+ } __packed;
+
+ /* Number of attr fork extents if NREXT64 is set. */
+ struct {
+ __be32 di_big_anextents;
+ __be16 di_nrext64_pad;
+ } __packed;
+ } __packed;
+ __u8 di_forkoff; /* attr fork offs, <<3 for 64b align */
+ __s8 di_aformat; /* format of attr fork's data */
+ __be32 di_dmevmask; /* DMIG event mask */
+ __be16 di_dmstate; /* DMIG state info */
+ __be16 di_flags; /* random flags, XFS_DIFLAG_... */
+ __be32 di_gen; /* generation number */
+
+ /* di_next_unlinked is the only non-core field in the old dinode */
+ __be32 di_next_unlinked;/* agi unlinked list ptr */
+
+ /* start of the extended dinode, writable fields */
+ __le32 di_crc; /* CRC of the inode */
+ __be64 di_changecount; /* number of attribute changes */
+ __be64 di_lsn; /* flush sequence */
+ __be64 di_flags2; /* more random flags */
+ __be32 di_cowextsize; /* basic cow extent size for file */
+ __u8 di_pad2[12]; /* more padding for future expansion */
+
+ /* fields only written to during inode creation */
+ xfs_timestamp_t di_crtime; /* time created */
+ __be64 di_ino; /* inode number */
+ uuid_t di_uuid; /* UUID of the filesystem */
+
+ /* structure must be padded to 64 bit alignment */
+};
+
+#define XFS_DINODE_CRC_OFF offsetof(struct xfs_dinode, di_crc)
+
+#define DI_MAX_FLUSH 0xffff
+
+/*
+ * Size of the core inode on disk. Version 1 and 2 inodes have
+ * the same size, but version 3 has grown a few additional fields.
+ */
+static inline uint xfs_dinode_size(int version)
+{
+ if (version == 3)
+ return sizeof(struct xfs_dinode);
+ return offsetof(struct xfs_dinode, di_crc);
+}
+
+/*
+ * The 32 bit link count in the inode theoretically maxes out at UINT_MAX.
+ * Since the pathconf interface is signed, we use 2^31 - 1 instead.
+ */
+#define XFS_MAXLINK ((1U << 31) - 1U)
+
+/*
+ * Values for di_format
+ *
+ * This enum is used in string mapping in xfs_trace.h; please keep the
+ * TRACE_DEFINE_ENUMs for it up to date.
+ */
+enum xfs_dinode_fmt {
+ XFS_DINODE_FMT_DEV, /* xfs_dev_t */
+ XFS_DINODE_FMT_LOCAL, /* bulk data */
+ XFS_DINODE_FMT_EXTENTS, /* struct xfs_bmbt_rec */
+ XFS_DINODE_FMT_BTREE, /* struct xfs_bmdr_block */
+ XFS_DINODE_FMT_UUID /* added long ago, but never used */
+};
+
+#define XFS_INODE_FORMAT_STR \
+ { XFS_DINODE_FMT_DEV, "dev" }, \
+ { XFS_DINODE_FMT_LOCAL, "local" }, \
+ { XFS_DINODE_FMT_EXTENTS, "extent" }, \
+ { XFS_DINODE_FMT_BTREE, "btree" }, \
+ { XFS_DINODE_FMT_UUID, "uuid" }
+
+/*
+ * Max values for extnum and aextnum.
+ *
+ * The original on-disk extent counts were held in signed fields, resulting in
+ * maximum extent counts of 2^31 and 2^15 for the data and attr forks
+ * respectively. Similarly the maximum extent length is limited to 2^21 blocks
+ * by the 21-bit wide blockcount field of a BMBT extent record.
+ *
+ * The newly introduced data fork extent counter can hold a 64-bit value,
+ * however the maximum number of extents in a file is also limited to 2^54
+ * extents by the 54-bit wide startoff field of a BMBT extent record.
+ *
+ * It is further limited by the maximum supported file size of 2^63
+ * *bytes*. This leads to a maximum extent count for maximally sized filesystem
+ * blocks (64kB) of:
+ *
+ * 2^63 bytes / 2^16 bytes per block = 2^47 blocks
+ *
+ * Rounding up 47 to the nearest multiple of bits-per-byte results in 48. Hence
+ * 2^48 was chosen as the maximum data fork extent count.
+ *
+ * The maximum file size that can be represented by the data fork extent counter
+ * in the worst case occurs when all extents are 1 block in length and each
+ * block is 1KB in size.
+ *
+ * With XFS_MAX_EXTCNT_DATA_FORK_SMALL representing maximum extent count and
+ * with 1KB sized blocks, a file can reach upto,
+ * 1KB * (2^31) = 2TB
+ *
+ * This is much larger than the theoretical maximum size of a directory
+ * i.e. XFS_DIR2_SPACE_SIZE * XFS_DIR2_MAX_SPACES = ~96GB.
+ *
+ * Hence, a directory inode can never overflow its data fork extent counter.
+ */
+#define XFS_MAX_EXTCNT_DATA_FORK_LARGE ((xfs_extnum_t)((1ULL << 48) - 1))
+#define XFS_MAX_EXTCNT_ATTR_FORK_LARGE ((xfs_extnum_t)((1ULL << 32) - 1))
+#define XFS_MAX_EXTCNT_DATA_FORK_SMALL ((xfs_extnum_t)((1ULL << 31) - 1))
+#define XFS_MAX_EXTCNT_ATTR_FORK_SMALL ((xfs_extnum_t)((1ULL << 15) - 1))
+
+/*
+ * When we upgrade an inode to the large extent counts, the maximum value by
+ * which the extent count can increase is bound by the change in size of the
+ * on-disk field. No upgrade operation should ever be adding more than a few
+ * tens of extents, so if we get a really large value it is a sign of a code bug
+ * or corruption.
+ */
+#define XFS_MAX_EXTCNT_UPGRADE_NR \
+ min(XFS_MAX_EXTCNT_ATTR_FORK_LARGE - XFS_MAX_EXTCNT_ATTR_FORK_SMALL, \
+ XFS_MAX_EXTCNT_DATA_FORK_LARGE - XFS_MAX_EXTCNT_DATA_FORK_SMALL)
+
+/*
+ * Inode minimum and maximum sizes.
+ */
+#define XFS_DINODE_MIN_LOG 8
+#define XFS_DINODE_MAX_LOG 11
+#define XFS_DINODE_MIN_SIZE (1 << XFS_DINODE_MIN_LOG)
+#define XFS_DINODE_MAX_SIZE (1 << XFS_DINODE_MAX_LOG)
+
+/*
+ * Inode size for given fs.
+ */
+#define XFS_DINODE_SIZE(mp) \
+ (xfs_has_v3inodes(mp) ? \
+ sizeof(struct xfs_dinode) : \
+ offsetof(struct xfs_dinode, di_crc))
+#define XFS_LITINO(mp) \
+ ((mp)->m_sb.sb_inodesize - XFS_DINODE_SIZE(mp))
+
+/*
+ * Inode data & attribute fork sizes, per inode.
+ */
+#define XFS_DFORK_BOFF(dip) ((int)((dip)->di_forkoff << 3))
+
+#define XFS_DFORK_DSIZE(dip,mp) \
+ ((dip)->di_forkoff ? XFS_DFORK_BOFF(dip) : XFS_LITINO(mp))
+#define XFS_DFORK_ASIZE(dip,mp) \
+ ((dip)->di_forkoff ? XFS_LITINO(mp) - XFS_DFORK_BOFF(dip) : 0)
+#define XFS_DFORK_SIZE(dip,mp,w) \
+ ((w) == XFS_DATA_FORK ? \
+ XFS_DFORK_DSIZE(dip, mp) : \
+ XFS_DFORK_ASIZE(dip, mp))
+
+#define XFS_DFORK_MAXEXT(dip, mp, w) \
+ (XFS_DFORK_SIZE(dip, mp, w) / sizeof(struct xfs_bmbt_rec))
+
+/*
+ * Return pointers to the data or attribute forks.
+ */
+#define XFS_DFORK_DPTR(dip) \
+ ((char *)dip + xfs_dinode_size(dip->di_version))
+#define XFS_DFORK_APTR(dip) \
+ (XFS_DFORK_DPTR(dip) + XFS_DFORK_BOFF(dip))
+#define XFS_DFORK_PTR(dip,w) \
+ ((w) == XFS_DATA_FORK ? XFS_DFORK_DPTR(dip) : XFS_DFORK_APTR(dip))
+
+#define XFS_DFORK_FORMAT(dip,w) \
+ ((w) == XFS_DATA_FORK ? \
+ (dip)->di_format : \
+ (dip)->di_aformat)
+
+/*
+ * For block and character special files the 32bit dev_t is stored at the
+ * beginning of the data fork.
+ */
+static inline xfs_dev_t xfs_dinode_get_rdev(struct xfs_dinode *dip)
+{
+ return be32_to_cpu(*(__be32 *)XFS_DFORK_DPTR(dip));
+}
+
+static inline void xfs_dinode_put_rdev(struct xfs_dinode *dip, xfs_dev_t rdev)
+{
+ *(__be32 *)XFS_DFORK_DPTR(dip) = cpu_to_be32(rdev);
+}
+
+/*
+ * Values for di_flags
+ */
+#define XFS_DIFLAG_REALTIME_BIT 0 /* file's blocks come from rt area */
+#define XFS_DIFLAG_PREALLOC_BIT 1 /* file space has been preallocated */
+#define XFS_DIFLAG_NEWRTBM_BIT 2 /* for rtbitmap inode, new format */
+#define XFS_DIFLAG_IMMUTABLE_BIT 3 /* inode is immutable */
+#define XFS_DIFLAG_APPEND_BIT 4 /* inode is append-only */
+#define XFS_DIFLAG_SYNC_BIT 5 /* inode is written synchronously */
+#define XFS_DIFLAG_NOATIME_BIT 6 /* do not update atime */
+#define XFS_DIFLAG_NODUMP_BIT 7 /* do not dump */
+#define XFS_DIFLAG_RTINHERIT_BIT 8 /* create with realtime bit set */
+#define XFS_DIFLAG_PROJINHERIT_BIT 9 /* create with parents projid */
+#define XFS_DIFLAG_NOSYMLINKS_BIT 10 /* disallow symlink creation */
+#define XFS_DIFLAG_EXTSIZE_BIT 11 /* inode extent size allocator hint */
+#define XFS_DIFLAG_EXTSZINHERIT_BIT 12 /* inherit inode extent size */
+#define XFS_DIFLAG_NODEFRAG_BIT 13 /* do not reorganize/defragment */
+#define XFS_DIFLAG_FILESTREAM_BIT 14 /* use filestream allocator */
+/* Do not use bit 15, di_flags is legacy and unchanging now */
+
+#define XFS_DIFLAG_REALTIME (1 << XFS_DIFLAG_REALTIME_BIT)
+#define XFS_DIFLAG_PREALLOC (1 << XFS_DIFLAG_PREALLOC_BIT)
+#define XFS_DIFLAG_NEWRTBM (1 << XFS_DIFLAG_NEWRTBM_BIT)
+#define XFS_DIFLAG_IMMUTABLE (1 << XFS_DIFLAG_IMMUTABLE_BIT)
+#define XFS_DIFLAG_APPEND (1 << XFS_DIFLAG_APPEND_BIT)
+#define XFS_DIFLAG_SYNC (1 << XFS_DIFLAG_SYNC_BIT)
+#define XFS_DIFLAG_NOATIME (1 << XFS_DIFLAG_NOATIME_BIT)
+#define XFS_DIFLAG_NODUMP (1 << XFS_DIFLAG_NODUMP_BIT)
+#define XFS_DIFLAG_RTINHERIT (1 << XFS_DIFLAG_RTINHERIT_BIT)
+#define XFS_DIFLAG_PROJINHERIT (1 << XFS_DIFLAG_PROJINHERIT_BIT)
+#define XFS_DIFLAG_NOSYMLINKS (1 << XFS_DIFLAG_NOSYMLINKS_BIT)
+#define XFS_DIFLAG_EXTSIZE (1 << XFS_DIFLAG_EXTSIZE_BIT)
+#define XFS_DIFLAG_EXTSZINHERIT (1 << XFS_DIFLAG_EXTSZINHERIT_BIT)
+#define XFS_DIFLAG_NODEFRAG (1 << XFS_DIFLAG_NODEFRAG_BIT)
+#define XFS_DIFLAG_FILESTREAM (1 << XFS_DIFLAG_FILESTREAM_BIT)
+
+#define XFS_DIFLAG_ANY \
+ (XFS_DIFLAG_REALTIME | XFS_DIFLAG_PREALLOC | XFS_DIFLAG_NEWRTBM | \
+ XFS_DIFLAG_IMMUTABLE | XFS_DIFLAG_APPEND | XFS_DIFLAG_SYNC | \
+ XFS_DIFLAG_NOATIME | XFS_DIFLAG_NODUMP | XFS_DIFLAG_RTINHERIT | \
+ XFS_DIFLAG_PROJINHERIT | XFS_DIFLAG_NOSYMLINKS | XFS_DIFLAG_EXTSIZE | \
+ XFS_DIFLAG_EXTSZINHERIT | XFS_DIFLAG_NODEFRAG | XFS_DIFLAG_FILESTREAM)
+
+/*
+ * Values for di_flags2 These start by being exposed to userspace in the upper
+ * 16 bits of the XFS_XFLAG_s range.
+ */
+#define XFS_DIFLAG2_DAX_BIT 0 /* use DAX for this inode */
+#define XFS_DIFLAG2_REFLINK_BIT 1 /* file's blocks may be shared */
+#define XFS_DIFLAG2_COWEXTSIZE_BIT 2 /* copy on write extent size hint */
+#define XFS_DIFLAG2_BIGTIME_BIT 3 /* big timestamps */
+#define XFS_DIFLAG2_NREXT64_BIT 4 /* large extent counters */
+
+#define XFS_DIFLAG2_DAX (1 << XFS_DIFLAG2_DAX_BIT)
+#define XFS_DIFLAG2_REFLINK (1 << XFS_DIFLAG2_REFLINK_BIT)
+#define XFS_DIFLAG2_COWEXTSIZE (1 << XFS_DIFLAG2_COWEXTSIZE_BIT)
+#define XFS_DIFLAG2_BIGTIME (1 << XFS_DIFLAG2_BIGTIME_BIT)
+#define XFS_DIFLAG2_NREXT64 (1 << XFS_DIFLAG2_NREXT64_BIT)
+
+#define XFS_DIFLAG2_ANY \
+ (XFS_DIFLAG2_DAX | XFS_DIFLAG2_REFLINK | XFS_DIFLAG2_COWEXTSIZE | \
+ XFS_DIFLAG2_BIGTIME | XFS_DIFLAG2_NREXT64)
+
+static inline bool xfs_dinode_has_bigtime(const struct xfs_dinode *dip)
+{
+ return dip->di_version >= 3 &&
+ (dip->di_flags2 & cpu_to_be64(XFS_DIFLAG2_BIGTIME));
+}
+
+static inline bool xfs_dinode_has_large_extent_counts(
+ const struct xfs_dinode *dip)
+{
+ return dip->di_version >= 3 &&
+ (dip->di_flags2 & cpu_to_be64(XFS_DIFLAG2_NREXT64));
+}
+
+/*
+ * Inode number format:
+ * low inopblog bits - offset in block
+ * next agblklog bits - block number in ag
+ * next agno_log bits - ag number
+ * high agno_log-agblklog-inopblog bits - 0
+ */
+#define XFS_INO_MASK(k) (uint32_t)((1ULL << (k)) - 1)
+#define XFS_INO_OFFSET_BITS(mp) (mp)->m_sb.sb_inopblog
+#define XFS_INO_AGBNO_BITS(mp) (mp)->m_sb.sb_agblklog
+#define XFS_INO_AGINO_BITS(mp) ((mp)->m_ino_geo.agino_log)
+#define XFS_INO_AGNO_BITS(mp) (mp)->m_agno_log
+#define XFS_INO_BITS(mp) \
+ XFS_INO_AGNO_BITS(mp) + XFS_INO_AGINO_BITS(mp)
+#define XFS_INO_TO_AGNO(mp,i) \
+ ((xfs_agnumber_t)((i) >> XFS_INO_AGINO_BITS(mp)))
+#define XFS_INO_TO_AGINO(mp,i) \
+ ((xfs_agino_t)(i) & XFS_INO_MASK(XFS_INO_AGINO_BITS(mp)))
+#define XFS_INO_TO_AGBNO(mp,i) \
+ (((xfs_agblock_t)(i) >> XFS_INO_OFFSET_BITS(mp)) & \
+ XFS_INO_MASK(XFS_INO_AGBNO_BITS(mp)))
+#define XFS_INO_TO_OFFSET(mp,i) \
+ ((int)(i) & XFS_INO_MASK(XFS_INO_OFFSET_BITS(mp)))
+#define XFS_INO_TO_FSB(mp,i) \
+ XFS_AGB_TO_FSB(mp, XFS_INO_TO_AGNO(mp,i), XFS_INO_TO_AGBNO(mp,i))
+#define XFS_AGINO_TO_INO(mp,a,i) \
+ (((xfs_ino_t)(a) << XFS_INO_AGINO_BITS(mp)) | (i))
+#define XFS_AGINO_TO_AGBNO(mp,i) ((i) >> XFS_INO_OFFSET_BITS(mp))
+#define XFS_AGINO_TO_OFFSET(mp,i) \
+ ((i) & XFS_INO_MASK(XFS_INO_OFFSET_BITS(mp)))
+#define XFS_OFFBNO_TO_AGINO(mp,b,o) \
+ ((xfs_agino_t)(((b) << XFS_INO_OFFSET_BITS(mp)) | (o)))
+#define XFS_FSB_TO_INO(mp, b) ((xfs_ino_t)((b) << XFS_INO_OFFSET_BITS(mp)))
+#define XFS_AGB_TO_AGINO(mp, b) ((xfs_agino_t)((b) << XFS_INO_OFFSET_BITS(mp)))
+
+#define XFS_MAXINUMBER ((xfs_ino_t)((1ULL << 56) - 1ULL))
+#define XFS_MAXINUMBER_32 ((xfs_ino_t)((1ULL << 32) - 1ULL))
+
+/*
+ * RealTime Device format definitions
+ */
+
+/* Min and max rt extent sizes, specified in bytes */
+#define XFS_MAX_RTEXTSIZE (1024 * 1024 * 1024) /* 1GB */
+#define XFS_DFL_RTEXTSIZE (64 * 1024) /* 64kB */
+#define XFS_MIN_RTEXTSIZE (4 * 1024) /* 4kB */
+
+#define XFS_BLOCKSIZE(mp) ((mp)->m_sb.sb_blocksize)
+#define XFS_BLOCKMASK(mp) ((mp)->m_blockmask)
+#define XFS_BLOCKWSIZE(mp) ((mp)->m_blockwsize)
+#define XFS_BLOCKWMASK(mp) ((mp)->m_blockwmask)
+
+/*
+ * RT Summary and bit manipulation macros.
+ */
+#define XFS_SUMOFFS(mp,ls,bb) ((int)((ls) * (mp)->m_sb.sb_rbmblocks + (bb)))
+#define XFS_SUMOFFSTOBLOCK(mp,s) \
+ (((s) * (uint)sizeof(xfs_suminfo_t)) >> (mp)->m_sb.sb_blocklog)
+#define XFS_SUMPTR(mp,bp,so) \
+ ((xfs_suminfo_t *)((bp)->b_addr + \
+ (((so) * (uint)sizeof(xfs_suminfo_t)) & XFS_BLOCKMASK(mp))))
+
+#define XFS_BITTOBLOCK(mp,bi) ((bi) >> (mp)->m_blkbit_log)
+#define XFS_BLOCKTOBIT(mp,bb) ((bb) << (mp)->m_blkbit_log)
+#define XFS_BITTOWORD(mp,bi) \
+ ((int)(((bi) >> XFS_NBWORDLOG) & XFS_BLOCKWMASK(mp)))
+
+#define XFS_RTMIN(a,b) ((a) < (b) ? (a) : (b))
+#define XFS_RTMAX(a,b) ((a) > (b) ? (a) : (b))
+
+#define XFS_RTLOBIT(w) xfs_lowbit32(w)
+#define XFS_RTHIBIT(w) xfs_highbit32(w)
+
+#define XFS_RTBLOCKLOG(b) xfs_highbit64(b)
+
+/*
+ * Dquot and dquot block format definitions
+ */
+#define XFS_DQUOT_MAGIC 0x4451 /* 'DQ' */
+#define XFS_DQUOT_VERSION (uint8_t)0x01 /* latest version number */
+
+#define XFS_DQTYPE_USER (1u << 0) /* user dquot record */
+#define XFS_DQTYPE_PROJ (1u << 1) /* project dquot record */
+#define XFS_DQTYPE_GROUP (1u << 2) /* group dquot record */
+#define XFS_DQTYPE_BIGTIME (1u << 7) /* large expiry timestamps */
+
+/* bitmask to determine if this is a user/group/project dquot */
+#define XFS_DQTYPE_REC_MASK (XFS_DQTYPE_USER | \
+ XFS_DQTYPE_PROJ | \
+ XFS_DQTYPE_GROUP)
+
+#define XFS_DQTYPE_ANY (XFS_DQTYPE_REC_MASK | \
+ XFS_DQTYPE_BIGTIME)
+
+/*
+ * XFS Quota Timers
+ * ================
+ *
+ * Traditional quota grace period expiration timers are an unsigned 32-bit
+ * seconds counter; time zero is the Unix epoch, Jan 1 00:00:01 UTC 1970.
+ * Note that an expiration value of zero means that the quota limit has not
+ * been reached, and therefore no expiration has been set. Therefore, the
+ * ondisk min and max defined here can be used directly to constrain the incore
+ * quota expiration timestamps on a Unix system.
+ *
+ * When bigtime is enabled, we trade two bits of precision to expand the
+ * expiration timeout range to match that of big inode timestamps. The min and
+ * max recorded here are the on-disk limits, not a Unix timestamp.
+ *
+ * The grace period for each quota type is stored in the root dquot (id = 0)
+ * and is applied to a non-root dquot when it exceeds the soft or hard limits.
+ * The length of quota grace periods are unsigned 32-bit quantities measured in
+ * units of seconds. A value of zero means to use the default period.
+ */
+
+/*
+ * Smallest possible ondisk quota expiration value with traditional timestamps.
+ * This corresponds exactly with the incore expiration Jan 1 00:00:01 UTC 1970.
+ */
+#define XFS_DQ_LEGACY_EXPIRY_MIN ((int64_t)1)
+
+/*
+ * Largest possible ondisk quota expiration value with traditional timestamps.
+ * This corresponds exactly with the incore expiration Feb 7 06:28:15 UTC 2106.
+ */
+#define XFS_DQ_LEGACY_EXPIRY_MAX ((int64_t)U32_MAX)
+
+/*
+ * Smallest possible ondisk quota expiration value with bigtime timestamps.
+ * This corresponds (after conversion to a Unix timestamp) with the incore
+ * expiration of Jan 1 00:00:04 UTC 1970.
+ */
+#define XFS_DQ_BIGTIME_EXPIRY_MIN (XFS_DQ_LEGACY_EXPIRY_MIN)
+
+/*
+ * Largest supported ondisk quota expiration value with bigtime timestamps.
+ * This corresponds (after conversion to a Unix timestamp) with an incore
+ * expiration of Jul 2 20:20:24 UTC 2486.
+ *
+ * The ondisk field supports values up to -1U, which corresponds to an incore
+ * expiration in 2514. This is beyond the maximum the bigtime inode timestamp,
+ * so we cap the maximum bigtime quota expiration to the max inode timestamp.
+ */
+#define XFS_DQ_BIGTIME_EXPIRY_MAX ((int64_t)4074815106U)
+
+/*
+ * The following conversion factors assist in converting a quota expiration
+ * timestamp between the incore and ondisk formats.
+ */
+#define XFS_DQ_BIGTIME_SHIFT (2)
+#define XFS_DQ_BIGTIME_SLACK ((int64_t)(1ULL << XFS_DQ_BIGTIME_SHIFT) - 1)
+
+/* Convert an incore quota expiration timestamp to an ondisk bigtime value. */
+static inline uint32_t xfs_dq_unix_to_bigtime(time64_t unix_seconds)
+{
+ /*
+ * Round the expiration timestamp up to the nearest bigtime timestamp
+ * that we can store, to give users the most time to fix problems.
+ */
+ return ((uint64_t)unix_seconds + XFS_DQ_BIGTIME_SLACK) >>
+ XFS_DQ_BIGTIME_SHIFT;
+}
+
+/* Convert an ondisk bigtime quota expiration value to an incore timestamp. */
+static inline time64_t xfs_dq_bigtime_to_unix(uint32_t ondisk_seconds)
+{
+ return (time64_t)ondisk_seconds << XFS_DQ_BIGTIME_SHIFT;
+}
+
+/*
+ * Default quota grace periods, ranging from zero (use the compiled defaults)
+ * to ~136 years. These are applied to a non-root dquot that has exceeded
+ * either limit.
+ */
+#define XFS_DQ_GRACE_MIN ((int64_t)0)
+#define XFS_DQ_GRACE_MAX ((int64_t)U32_MAX)
+
+/*
+ * This is the main portion of the on-disk representation of quota information
+ * for a user. We pad this with some more expansion room to construct the on
+ * disk structure.
+ */
+struct xfs_disk_dquot {
+ __be16 d_magic; /* dquot magic = XFS_DQUOT_MAGIC */
+ __u8 d_version; /* dquot version */
+ __u8 d_type; /* XFS_DQTYPE_USER/PROJ/GROUP */
+ __be32 d_id; /* user,project,group id */
+ __be64 d_blk_hardlimit;/* absolute limit on disk blks */
+ __be64 d_blk_softlimit;/* preferred limit on disk blks */
+ __be64 d_ino_hardlimit;/* maximum # allocated inodes */
+ __be64 d_ino_softlimit;/* preferred inode limit */
+ __be64 d_bcount; /* disk blocks owned by the user */
+ __be64 d_icount; /* inodes owned by the user */
+ __be32 d_itimer; /* zero if within inode limits if not,
+ this is when we refuse service */
+ __be32 d_btimer; /* similar to above; for disk blocks */
+ __be16 d_iwarns; /* warnings issued wrt num inodes */
+ __be16 d_bwarns; /* warnings issued wrt disk blocks */
+ __be32 d_pad0; /* 64 bit align */
+ __be64 d_rtb_hardlimit;/* absolute limit on realtime blks */
+ __be64 d_rtb_softlimit;/* preferred limit on RT disk blks */
+ __be64 d_rtbcount; /* realtime blocks owned */
+ __be32 d_rtbtimer; /* similar to above; for RT disk blocks */
+ __be16 d_rtbwarns; /* warnings issued wrt RT disk blocks */
+ __be16 d_pad;
+};
+
+/*
+ * This is what goes on disk. This is separated from the xfs_disk_dquot because
+ * carrying the unnecessary padding would be a waste of memory.
+ */
+struct xfs_dqblk {
+ struct xfs_disk_dquot dd_diskdq; /* portion living incore as well */
+ char dd_fill[4];/* filling for posterity */
+
+ /*
+ * These two are only present on filesystems with the CRC bits set.
+ */
+ __be32 dd_crc; /* checksum */
+ __be64 dd_lsn; /* last modification in log */
+ uuid_t dd_uuid; /* location information */
+};
+
+#define XFS_DQUOT_CRC_OFF offsetof(struct xfs_dqblk, dd_crc)
+
+/*
+ * This defines the unit of allocation of dquots.
+ *
+ * Currently, it is just one file system block, and a 4K blk contains 30
+ * (136 * 30 = 4080) dquots. It's probably not worth trying to make
+ * this more dynamic.
+ *
+ * However, if this number is changed, we have to make sure that we don't
+ * implicitly assume that we do allocations in chunks of a single filesystem
+ * block in the dquot/xqm code.
+ *
+ * This is part of the ondisk format because the structure size is not a power
+ * of two, which leaves slack at the end of the disk block.
+ */
+#define XFS_DQUOT_CLUSTER_SIZE_FSB (xfs_filblks_t)1
+
+/*
+ * Remote symlink format and access functions.
+ */
+#define XFS_SYMLINK_MAGIC 0x58534c4d /* XSLM */
+
+struct xfs_dsymlink_hdr {
+ __be32 sl_magic;
+ __be32 sl_offset;
+ __be32 sl_bytes;
+ __be32 sl_crc;
+ uuid_t sl_uuid;
+ __be64 sl_owner;
+ __be64 sl_blkno;
+ __be64 sl_lsn;
+};
+
+#define XFS_SYMLINK_CRC_OFF offsetof(struct xfs_dsymlink_hdr, sl_crc)
+
+#define XFS_SYMLINK_MAXLEN 1024
+/*
+ * The maximum pathlen is 1024 bytes. Since the minimum file system
+ * blocksize is 512 bytes, we can get a max of 3 extents back from
+ * bmapi when crc headers are taken into account.
+ */
+#define XFS_SYMLINK_MAPS 3
+
+#define XFS_SYMLINK_BUF_SPACE(mp, bufsize) \
+ ((bufsize) - (xfs_has_crc((mp)) ? \
+ sizeof(struct xfs_dsymlink_hdr) : 0))
+
+
+/*
+ * Allocation Btree format definitions
+ *
+ * There are two on-disk btrees, one sorted by blockno and one sorted
+ * by blockcount and blockno. All blocks look the same to make the code
+ * simpler; if we have time later, we'll make the optimizations.
+ */
+#define XFS_ABTB_MAGIC 0x41425442 /* 'ABTB' for bno tree */
+#define XFS_ABTB_CRC_MAGIC 0x41423342 /* 'AB3B' */
+#define XFS_ABTC_MAGIC 0x41425443 /* 'ABTC' for cnt tree */
+#define XFS_ABTC_CRC_MAGIC 0x41423343 /* 'AB3C' */
+
+/*
+ * Data record/key structure
+ */
+typedef struct xfs_alloc_rec {
+ __be32 ar_startblock; /* starting block number */
+ __be32 ar_blockcount; /* count of free blocks */
+} xfs_alloc_rec_t, xfs_alloc_key_t;
+
+typedef struct xfs_alloc_rec_incore {
+ xfs_agblock_t ar_startblock; /* starting block number */
+ xfs_extlen_t ar_blockcount; /* count of free blocks */
+} xfs_alloc_rec_incore_t;
+
+/* btree pointer type */
+typedef __be32 xfs_alloc_ptr_t;
+
+/*
+ * Block numbers in the AG:
+ * SB is sector 0, AGF is sector 1, AGI is sector 2, AGFL is sector 3.
+ */
+#define XFS_BNO_BLOCK(mp) ((xfs_agblock_t)(XFS_AGFL_BLOCK(mp) + 1))
+#define XFS_CNT_BLOCK(mp) ((xfs_agblock_t)(XFS_BNO_BLOCK(mp) + 1))
+
+
+/*
+ * Inode Allocation Btree format definitions
+ *
+ * There is a btree for the inode map per allocation group.
+ */
+#define XFS_IBT_MAGIC 0x49414254 /* 'IABT' */
+#define XFS_IBT_CRC_MAGIC 0x49414233 /* 'IAB3' */
+#define XFS_FIBT_MAGIC 0x46494254 /* 'FIBT' */
+#define XFS_FIBT_CRC_MAGIC 0x46494233 /* 'FIB3' */
+
+typedef uint64_t xfs_inofree_t;
+#define XFS_INODES_PER_CHUNK (NBBY * sizeof(xfs_inofree_t))
+#define XFS_INODES_PER_CHUNK_LOG (XFS_NBBYLOG + 3)
+#define XFS_INOBT_ALL_FREE ((xfs_inofree_t)-1)
+#define XFS_INOBT_MASK(i) ((xfs_inofree_t)1 << (i))
+
+#define XFS_INOBT_HOLEMASK_FULL 0 /* holemask for full chunk */
+#define XFS_INOBT_HOLEMASK_BITS (NBBY * sizeof(uint16_t))
+#define XFS_INODES_PER_HOLEMASK_BIT \
+ (XFS_INODES_PER_CHUNK / (NBBY * sizeof(uint16_t)))
+
+static inline xfs_inofree_t xfs_inobt_maskn(int i, int n)
+{
+ return ((n >= XFS_INODES_PER_CHUNK ? 0 : XFS_INOBT_MASK(n)) - 1) << i;
+}
+
+/*
+ * The on-disk inode record structure has two formats. The original "full"
+ * format uses a 4-byte freecount. The "sparse" format uses a 1-byte freecount
+ * and replaces the 3 high-order freecount bytes wth the holemask and inode
+ * count.
+ *
+ * The holemask of the sparse record format allows an inode chunk to have holes
+ * that refer to blocks not owned by the inode record. This facilitates inode
+ * allocation in the event of severe free space fragmentation.
+ */
+typedef struct xfs_inobt_rec {
+ __be32 ir_startino; /* starting inode number */
+ union {
+ struct {
+ __be32 ir_freecount; /* count of free inodes */
+ } f;
+ struct {
+ __be16 ir_holemask;/* hole mask for sparse chunks */
+ __u8 ir_count; /* total inode count */
+ __u8 ir_freecount; /* count of free inodes */
+ } sp;
+ } ir_u;
+ __be64 ir_free; /* free inode mask */
+} xfs_inobt_rec_t;
+
+typedef struct xfs_inobt_rec_incore {
+ xfs_agino_t ir_startino; /* starting inode number */
+ uint16_t ir_holemask; /* hole mask for sparse chunks */
+ uint8_t ir_count; /* total inode count */
+ uint8_t ir_freecount; /* count of free inodes (set bits) */
+ xfs_inofree_t ir_free; /* free inode mask */
+} xfs_inobt_rec_incore_t;
+
+static inline bool xfs_inobt_issparse(uint16_t holemask)
+{
+ /* non-zero holemask represents a sparse rec. */
+ return holemask;
+}
+
+/*
+ * Key structure
+ */
+typedef struct xfs_inobt_key {
+ __be32 ir_startino; /* starting inode number */
+} xfs_inobt_key_t;
+
+/* btree pointer type */
+typedef __be32 xfs_inobt_ptr_t;
+
+/*
+ * block numbers in the AG.
+ */
+#define XFS_IBT_BLOCK(mp) ((xfs_agblock_t)(XFS_CNT_BLOCK(mp) + 1))
+#define XFS_FIBT_BLOCK(mp) ((xfs_agblock_t)(XFS_IBT_BLOCK(mp) + 1))
+
+/*
+ * Reverse mapping btree format definitions
+ *
+ * There is a btree for the reverse map per allocation group
+ */
+#define XFS_RMAP_CRC_MAGIC 0x524d4233 /* 'RMB3' */
+
+/*
+ * Ownership info for an extent. This is used to create reverse-mapping
+ * entries.
+ */
+#define XFS_OWNER_INFO_ATTR_FORK (1 << 0)
+#define XFS_OWNER_INFO_BMBT_BLOCK (1 << 1)
+struct xfs_owner_info {
+ uint64_t oi_owner;
+ xfs_fileoff_t oi_offset;
+ unsigned int oi_flags;
+};
+
+/*
+ * Special owner types.
+ *
+ * Seeing as we only support up to 8EB, we have the upper bit of the owner field
+ * to tell us we have a special owner value. We use these for static metadata
+ * allocated at mkfs/growfs time, as well as for freespace management metadata.
+ */
+#define XFS_RMAP_OWN_NULL (-1ULL) /* No owner, for growfs */
+#define XFS_RMAP_OWN_UNKNOWN (-2ULL) /* Unknown owner, for EFI recovery */
+#define XFS_RMAP_OWN_FS (-3ULL) /* static fs metadata */
+#define XFS_RMAP_OWN_LOG (-4ULL) /* static fs metadata */
+#define XFS_RMAP_OWN_AG (-5ULL) /* AG freespace btree blocks */
+#define XFS_RMAP_OWN_INOBT (-6ULL) /* Inode btree blocks */
+#define XFS_RMAP_OWN_INODES (-7ULL) /* Inode chunk */
+#define XFS_RMAP_OWN_REFC (-8ULL) /* refcount tree */
+#define XFS_RMAP_OWN_COW (-9ULL) /* cow allocations */
+#define XFS_RMAP_OWN_MIN (-10ULL) /* 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
+
+/*
+ * 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_has_finobt(((mp))) ? \
+ XFS_FIBT_BLOCK(mp) + 1 : \
+ XFS_IBT_BLOCK(mp) + 1)
+
+/*
+ * Reference Count Btree format definitions
+ *
+ */
+#define XFS_REFC_CRC_MAGIC 0x52334643 /* 'R3FC' */
+
+unsigned int xfs_refc_block(struct xfs_mount *mp);
+
+/*
+ * Data record/key structure
+ *
+ * Each record associates a range of physical blocks (starting at
+ * rc_startblock and ending rc_blockcount blocks later) with a reference
+ * count (rc_refcount). Extents that are being used to stage a copy on
+ * write (CoW) operation are recorded in the refcount btree with a
+ * refcount of 1. All other records must have a refcount > 1 and must
+ * track an extent mapped only by file data forks.
+ *
+ * Extents with a single owner (attributes, metadata, non-shared file
+ * data) are not tracked here. Free space is also not tracked here.
+ * This is consistent with pre-reflink XFS.
+ */
+
+/*
+ * Extents that are being used to stage a copy on write are stored
+ * in the refcount btree with a refcount of 1 and the upper bit set
+ * on the startblock. This speeds up mount time deletion of stale
+ * staging extents because they're all at the right side of the tree.
+ */
+#define XFS_REFC_COWFLAG (1U << 31)
+#define REFCNTBT_COWFLAG_BITLEN 1
+#define REFCNTBT_AGBLOCK_BITLEN 31
+
+struct xfs_refcount_rec {
+ __be32 rc_startblock; /* starting block number */
+ __be32 rc_blockcount; /* count of blocks */
+ __be32 rc_refcount; /* number of inodes linked here */
+};
+
+struct xfs_refcount_key {
+ __be32 rc_startblock; /* starting block number */
+};
+
+#define MAXREFCOUNT ((xfs_nlink_t)~0U)
+#define MAXREFCEXTLEN ((xfs_extlen_t)~0U)
+
+/* btree pointer type */
+typedef __be32 xfs_refcount_ptr_t;
+
+
+/*
+ * BMAP Btree format definitions
+ *
+ * This includes both the root block definition that sits inside an inode fork
+ * and the record/pointer formats for the leaf/node in the blocks.
+ */
+#define XFS_BMAP_MAGIC 0x424d4150 /* 'BMAP' */
+#define XFS_BMAP_CRC_MAGIC 0x424d4133 /* 'BMA3' */
+
+/*
+ * Bmap root header, on-disk form only.
+ */
+typedef struct xfs_bmdr_block {
+ __be16 bb_level; /* 0 is a leaf */
+ __be16 bb_numrecs; /* current # of data records */
+} xfs_bmdr_block_t;
+
+/*
+ * Bmap btree record and extent descriptor.
+ * l0:63 is an extent flag (value 1 indicates non-normal).
+ * l0:9-62 are startoff.
+ * l0:0-8 and l1:21-63 are startblock.
+ * l1:0-20 are blockcount.
+ */
+#define BMBT_EXNTFLAG_BITLEN 1
+#define BMBT_STARTOFF_BITLEN 54
+#define BMBT_STARTBLOCK_BITLEN 52
+#define BMBT_BLOCKCOUNT_BITLEN 21
+
+#define BMBT_STARTOFF_MASK ((1ULL << BMBT_STARTOFF_BITLEN) - 1)
+#define BMBT_BLOCKCOUNT_MASK ((1ULL << BMBT_BLOCKCOUNT_BITLEN) - 1)
+
+#define XFS_MAX_BMBT_EXTLEN ((xfs_extlen_t)(BMBT_BLOCKCOUNT_MASK))
+
+/*
+ * bmbt records have a file offset (block) field that is 54 bits wide, so this
+ * is the largest xfs_fileoff_t that we ever expect to see.
+ */
+#define XFS_MAX_FILEOFF (BMBT_STARTOFF_MASK + BMBT_BLOCKCOUNT_MASK)
+
+typedef struct xfs_bmbt_rec {
+ __be64 l0, l1;
+} xfs_bmbt_rec_t;
+
+typedef uint64_t xfs_bmbt_rec_base_t; /* use this for casts */
+typedef xfs_bmbt_rec_t xfs_bmdr_rec_t;
+
+/*
+ * Values and macros for delayed-allocation startblock fields.
+ */
+#define STARTBLOCKVALBITS 17
+#define STARTBLOCKMASKBITS (15 + 20)
+#define STARTBLOCKMASK \
+ (((((xfs_fsblock_t)1) << STARTBLOCKMASKBITS) - 1) << STARTBLOCKVALBITS)
+
+static inline int isnullstartblock(xfs_fsblock_t x)
+{
+ return ((x) & STARTBLOCKMASK) == STARTBLOCKMASK;
+}
+
+static inline xfs_fsblock_t nullstartblock(int k)
+{
+ ASSERT(k < (1 << STARTBLOCKVALBITS));
+ return STARTBLOCKMASK | (k);
+}
+
+static inline xfs_filblks_t startblockval(xfs_fsblock_t x)
+{
+ return (xfs_filblks_t)((x) & ~STARTBLOCKMASK);
+}
+
+/*
+ * Key structure for non-leaf levels of the tree.
+ */
+typedef struct xfs_bmbt_key {
+ __be64 br_startoff; /* starting file offset */
+} xfs_bmbt_key_t, xfs_bmdr_key_t;
+
+/* btree pointer type */
+typedef __be64 xfs_bmbt_ptr_t, xfs_bmdr_ptr_t;
+
+
+/*
+ * Generic Btree block format definitions
+ *
+ * This is a combination of the actual format used on disk for short and long
+ * format btrees. The first three fields are shared by both format, but the
+ * pointers are different and should be used with care.
+ *
+ * To get the size of the actual short or long form headers please use the size
+ * macros below. Never use sizeof(xfs_btree_block).
+ *
+ * The blkno, crc, lsn, owner and uuid fields are only available in filesystems
+ * with the crc feature bit, and all accesses to them must be conditional on
+ * that flag.
+ */
+/* short form block header */
+struct xfs_btree_block_shdr {
+ __be32 bb_leftsib;
+ __be32 bb_rightsib;
+
+ __be64 bb_blkno;
+ __be64 bb_lsn;
+ uuid_t bb_uuid;
+ __be32 bb_owner;
+ __le32 bb_crc;
+};
+
+/* long form block header */
+struct xfs_btree_block_lhdr {
+ __be64 bb_leftsib;
+ __be64 bb_rightsib;
+
+ __be64 bb_blkno;
+ __be64 bb_lsn;
+ uuid_t bb_uuid;
+ __be64 bb_owner;
+ __le32 bb_crc;
+ __be32 bb_pad; /* padding for alignment */
+};
+
+struct xfs_btree_block {
+ __be32 bb_magic; /* magic number for block type */
+ __be16 bb_level; /* 0 is a leaf */
+ __be16 bb_numrecs; /* current # of data records */
+ union {
+ struct xfs_btree_block_shdr s;
+ struct xfs_btree_block_lhdr l;
+ } bb_u; /* rest */
+};
+
+/* size of a short form block */
+#define XFS_BTREE_SBLOCK_LEN \
+ (offsetof(struct xfs_btree_block, bb_u) + \
+ offsetof(struct xfs_btree_block_shdr, bb_blkno))
+/* size of a long form block */
+#define XFS_BTREE_LBLOCK_LEN \
+ (offsetof(struct xfs_btree_block, bb_u) + \
+ offsetof(struct xfs_btree_block_lhdr, bb_blkno))
+
+/* sizes of CRC enabled btree blocks */
+#define XFS_BTREE_SBLOCK_CRC_LEN \
+ (offsetof(struct xfs_btree_block, bb_u) + \
+ sizeof(struct xfs_btree_block_shdr))
+#define XFS_BTREE_LBLOCK_CRC_LEN \
+ (offsetof(struct xfs_btree_block, bb_u) + \
+ sizeof(struct xfs_btree_block_lhdr))
+
+#define XFS_BTREE_SBLOCK_CRC_OFF \
+ offsetof(struct xfs_btree_block, bb_u.s.bb_crc)
+#define XFS_BTREE_LBLOCK_CRC_OFF \
+ offsetof(struct xfs_btree_block, bb_u.l.bb_crc)
+
+/*
+ * On-disk XFS access control list structure.
+ */
+struct xfs_acl_entry {
+ __be32 ae_tag;
+ __be32 ae_id;
+ __be16 ae_perm;
+ __be16 ae_pad; /* fill the implicit hole in the structure */
+};
+
+struct xfs_acl {
+ __be32 acl_cnt;
+ struct xfs_acl_entry acl_entry[];
+};
+
+/*
+ * The number of ACL entries allowed is defined by the on-disk format.
+ * For v4 superblocks, that is limited to 25 entries. For v5 superblocks, it is
+ * limited only by the maximum size of the xattr that stores the information.
+ */
+#define XFS_ACL_MAX_ENTRIES(mp) \
+ (xfs_has_crc(mp) \
+ ? (XFS_XATTR_SIZE_MAX - sizeof(struct xfs_acl)) / \
+ sizeof(struct xfs_acl_entry) \
+ : 25)
+
+#define XFS_ACL_SIZE(cnt) \
+ (sizeof(struct xfs_acl) + \
+ sizeof(struct xfs_acl_entry) * cnt)
+
+#define XFS_ACL_MAX_SIZE(mp) \
+ XFS_ACL_SIZE(XFS_ACL_MAX_ENTRIES((mp)))
+
+
+/* On-disk XFS extended attribute names */
+#define SGI_ACL_FILE "SGI_ACL_FILE"
+#define SGI_ACL_DEFAULT "SGI_ACL_DEFAULT"
+#define SGI_ACL_FILE_SIZE (sizeof(SGI_ACL_FILE)-1)
+#define SGI_ACL_DEFAULT_SIZE (sizeof(SGI_ACL_DEFAULT)-1)
+
+#endif /* __XFS_FORMAT_H__ */