[PATCH 07/16] xfs: define the on-disk rmap btree format

Dave Chinner
2016-03-08T04:17:12Z

From: Dave Chinner <dchinner@redhat.com>

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.wong@oracle.com: record owner and offset info in rmap btree]
[darrick.wong@oracle.com: fork, bmbt and unwritten state in rmap btree]

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
---
fs/xfs/Makefile | 1 +
fs/xfs/libxfs/xfs_btree.c | 3 +
fs/xfs/libxfs/xfs_btree.h | 18 +++--
fs/xfs/libxfs/xfs_format.h | 95 +++++++++++++++++++++++
fs/xfs/libxfs/xfs_rmap_btree.c | 170 +++++++++++++++++++++++++++++++++++++++++
fs/xfs/libxfs/xfs_rmap_btree.h | 31 ++++++++
fs/xfs/libxfs/xfs_sb.c | 6 ++
fs/xfs/libxfs/xfs_shared.h | 2 +
fs/xfs/xfs_mount.h | 2 +
fs/xfs/xfs_ondisk.h | 3 +
10 files changed, 323 insertions(+), 8 deletions(-)
create mode 100644 fs/xfs/libxfs/xfs_rmap_btree.c

diff --git a/fs/xfs/Makefile b/fs/xfs/Makefile
index c202ce3..9391080 100644
--- a/fs/xfs/Makefile
+++ b/fs/xfs/Makefile
@@ -52,6 +52,7 @@ xfs-y += $(addprefix libxfs/, \
xfs_inode_buf.o \
xfs_log_rlimit.o \
xfs_rmap.o \
+ xfs_rmap_btree.o \
xfs_sb.o \
xfs_symlink_remote.o \
xfs_trans_resv.o \
diff --git a/fs/xfs/libxfs/xfs_btree.c b/fs/xfs/libxfs/xfs_btree.c
index 5953764..1240117 100644
--- a/fs/xfs/libxfs/xfs_btree.c
+++ b/fs/xfs/libxfs/xfs_btree.c
@@ -1144,6 +1144,9 @@ xfs_btree_set_refs(
case XFS_BTNUM_BMAP:
xfs_buf_set_ref(bp, XFS_BMAP_BTREE_REF);
break;
+ case XFS_BTNUM_RMAP:
+ xfs_buf_set_ref(bp, XFS_RMAP_BTREE_REF);
+ break;
default:
ASSERT(0);
}
diff --git a/fs/xfs/libxfs/xfs_btree.h b/fs/xfs/libxfs/xfs_btree.h
index 1fcf272..07fa27e 100644
--- a/fs/xfs/libxfs/xfs_btree.h
+++ b/fs/xfs/libxfs/xfs_btree.h
@@ -38,17 +38,19 @@ union xfs_btree_ptr {
};

union xfs_btree_key {
- xfs_bmbt_key_t bmbt;
- xfs_bmdr_key_t bmbr; /* bmbt root block */
- xfs_alloc_key_t alloc;
- xfs_inobt_key_t inobt;
+ struct xfs_bmbt_key bmbt;
+ xfs_bmdr_key_t bmbr; /* bmbt root block */
+ xfs_alloc_key_t alloc;
+ struct xfs_inobt_key inobt;
+ struct xfs_rmap_key rmap;
};

union xfs_btree_rec {
- xfs_bmbt_rec_t bmbt;
- xfs_bmdr_rec_t bmbr; /* bmbt root block */
- xfs_alloc_rec_t alloc;
- xfs_inobt_rec_t inobt;
+ struct xfs_bmbt_rec bmbt;
+ xfs_bmdr_rec_t bmbr; /* bmbt root block */
+ struct xfs_alloc_rec alloc;
+ struct xfs_inobt_rec inobt;
+ struct xfs_rmap_rec rmap;
};

/*
diff --git a/fs/xfs/libxfs/xfs_format.h b/fs/xfs/libxfs/xfs_format.h
index 232c145..508b3ea 100644
--- a/fs/xfs/libxfs/xfs_format.h
+++ b/fs/xfs/libxfs/xfs_format.h
@@ -1384,11 +1384,106 @@ xfs_rmap_ino_owner(
#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_blockcount:31 is the unwritten extent flag (same as l0:63 in bmbt)
+ * rm_blockcount:0-30 are the extent length
+ * rm_offset:63 is the attribute fork flag
+ * rm_offset:62 is the bmbt block flag
+ * rm_offset:0-61 is the block offset within the inode
+ */
+#define XFS_RMAP_OFF_ATTR ((__uint64_t)1ULL << 63)
+#define XFS_RMAP_OFF_BMBT ((__uint64_t)1ULL << 62)
+#define XFS_RMAP_LEN_UNWRITTEN ((xfs_extlen_t)1U << 31)
+
+#define XFS_RMAP_OFF_MASK ~(XFS_RMAP_OFF_ATTR | XFS_RMAP_OFF_BMBT)
+#define XFS_RMAP_LEN_MASK ~XFS_RMAP_LEN_UNWRITTEN
+
+#define XFS_RMAP_OFF(off) ((off) & XFS_RMAP_OFF_MASK)
+#define XFS_RMAP_LEN(len) ((len) & XFS_RMAP_LEN_MASK)
+
+#define XFS_RMAP_IS_BMBT(off) (!!((off) & XFS_RMAP_OFF_BMBT))
+#define XFS_RMAP_IS_ATTR_FORK(off) (!!((off) & XFS_RMAP_OFF_ATTR))
+#define XFS_RMAP_IS_UNWRITTEN(len) (!!((len) & XFS_RMAP_LEN_UNWRITTEN))
+
+#define RMAPBT_STARTBLOCK_BITLEN 32
+#define RMAPBT_EXNTFLAG_BITLEN 1
+#define RMAPBT_BLOCKCOUNT_BITLEN 31
+#define RMAPBT_OWNER_BITLEN 64
+#define RMAPBT_ATTRFLAG_BITLEN 1
+#define RMAPBT_BMBTFLAG_BITLEN 1
+#define RMAPBT_OFFSET_BITLEN 62
+
+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 */
+};
+
+/*
+ * 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 : \
XFS_IBT_BLOCK(mp) + 1)

+static inline void
+xfs_owner_info_unpack(
+ struct xfs_owner_info *oinfo,
+ uint64_t *owner,
+ uint64_t *offset)
+{
+ __uint64_t r;
+
+ *owner = oinfo->oi_owner;
+ r = oinfo->oi_offset;
+ if (oinfo->oi_flags & XFS_RMAP_INO_ATTR_FORK)
+ r |= XFS_RMAP_OFF_ATTR;
+ if (oinfo->oi_flags & XFS_RMAP_BMBT_BLOCK)
+ r |= XFS_RMAP_OFF_BMBT;
+ *offset = r;
+}
+
+static inline void
+xfs_owner_info_pack(
+ struct xfs_owner_info *oinfo,
+ uint64_t owner,
+ uint64_t offset)
+{
+ oinfo->oi_owner = owner;
+ oinfo->oi_offset = XFS_RMAP_OFF(offset);
+ oinfo->oi_flags = 0;
+ if (XFS_RMAP_IS_ATTR_FORK(offset))
+ oinfo->oi_flags |= XFS_RMAP_INO_ATTR_FORK;
+ if (XFS_RMAP_IS_BMBT(offset))
+ oinfo->oi_flags |= XFS_RMAP_BMBT_BLOCK;
+}
+
/*
* BMAP Btree format definitions
*
diff --git a/fs/xfs/libxfs/xfs_rmap_btree.c b/fs/xfs/libxfs/xfs_rmap_btree.c
new file mode 100644
index 0000000..882e8e2
--- /dev/null
+++ b/fs/xfs/libxfs/xfs_rmap_btree.c
@@ -0,0 +1,170 @@
+/*
+ * Copyright (c) 2014 Red Hat, Inc.
+ * All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+#include "xfs.h"
+#include "xfs_fs.h"
+#include "xfs_shared.h"
+#include "xfs_format.h"
+#include "xfs_log_format.h"
+#include "xfs_trans_resv.h"
+#include "xfs_bit.h"
+#include "xfs_sb.h"
+#include "xfs_mount.h"
+#include "xfs_inode.h"
+#include "xfs_trans.h"
+#include "xfs_alloc.h"
+#include "xfs_btree.h"
+#include "xfs_rmap_btree.h"
+#include "xfs_trace.h"
+#include "xfs_cksum.h"
+#include "xfs_error.h"
+#include "xfs_extent_busy.h"
+
+static struct xfs_btree_cur *
+xfs_rmapbt_dup_cursor(
+ struct xfs_btree_cur *cur)
+{
+ return xfs_rmapbt_init_cursor(cur->bc_mp, cur->bc_tp,
+ cur->bc_private.a.agbp, cur->bc_private.a.agno);
+}
+
+static bool
+xfs_rmapbt_verify(
+ struct xfs_buf *bp)
+{
+ struct xfs_mount *mp = bp->b_target->bt_mount;
+ struct xfs_btree_block *block = XFS_BUF_TO_BLOCK(bp);
+ struct xfs_perag *pag = bp->b_pag;
+ unsigned int level;
+
+ /*
+ * magic number and level verification
+ *
+ * During growfs operations, we can't verify the exact level or owner as
+ * the perag is not fully initialised and hence not attached to the
+ * buffer. In this case, check against the maximum tree depth.
+ *
+ * Similarly, during log recovery we will have a perag structure
+ * attached, but the agf information will not yet have been initialised
+ * from the on disk AGF. Again, we can only check against maximum limits
+ * in this case.
+ */
+ if (block->bb_magic != cpu_to_be32(XFS_RMAP_CRC_MAGIC))
+ return false;
+
+ if (!xfs_sb_version_hasrmapbt(&mp->m_sb))
+ return false;
+ if (!xfs_btree_sblock_v5hdr_verify(bp))
+ return false;
+
+ level = be16_to_cpu(block->bb_level);
+ if (pag && pag->pagf_init) {
+ if (level >= pag->pagf_levels[XFS_BTNUM_RMAPi])
+ return false;
+ } else if (level >= mp->m_ag_maxlevels)
+ return false;
+
+ return xfs_btree_sblock_verify(bp, mp->m_rmap_mxr[level != 0]);
+}
+
+static void
+xfs_rmapbt_read_verify(
+ struct xfs_buf *bp)
+{
+ if (!xfs_btree_sblock_verify_crc(bp))
+ xfs_buf_ioerror(bp, -EFSBADCRC);
+ else if (!xfs_rmapbt_verify(bp))
+ xfs_buf_ioerror(bp, -EFSCORRUPTED);
+
+ if (bp->b_error) {
+ trace_xfs_btree_corrupt(bp, _RET_IP_);
+ xfs_verifier_error(bp);
+ }
+}
+
+static void
+xfs_rmapbt_write_verify(
+ struct xfs_buf *bp)
+{
+ if (!xfs_rmapbt_verify(bp)) {
+ trace_xfs_btree_corrupt(bp, _RET_IP_);
+ xfs_buf_ioerror(bp, -EFSCORRUPTED);
+ xfs_verifier_error(bp);
+ return;
+ }
+ xfs_btree_sblock_calc_crc(bp);
+
+}
+
+const struct xfs_buf_ops xfs_rmapbt_buf_ops = {
+ .name = "xfs_rmapbt",
+ .verify_read = xfs_rmapbt_read_verify,
+ .verify_write = xfs_rmapbt_write_verify,
+};
+
+static const struct xfs_btree_ops xfs_rmapbt_ops = {
+ .rec_len = sizeof(struct xfs_rmap_rec),
+ .key_len = sizeof(struct xfs_rmap_key),
+
+ .dup_cursor = xfs_rmapbt_dup_cursor,
+ .buf_ops = &xfs_rmapbt_buf_ops,
+};
+
+/*
+ * Allocate a new allocation btree cursor.
+ */
+struct xfs_btree_cur *
+xfs_rmapbt_init_cursor(
+ struct xfs_mount *mp,
+ struct xfs_trans *tp,
+ struct xfs_buf *agbp,
+ xfs_agnumber_t agno)
+{
+ struct xfs_agf *agf = XFS_BUF_TO_AGF(agbp);
+ struct xfs_btree_cur *cur;
+
+ cur = kmem_zone_zalloc(xfs_btree_cur_zone, KM_SLEEP);
+ cur->bc_tp = tp;
+ cur->bc_mp = mp;
+ cur->bc_btnum = XFS_BTNUM_RMAP;
+ cur->bc_flags = XFS_BTREE_CRC_BLOCKS;
+ cur->bc_blocklog = mp->m_sb.sb_blocklog;
+ cur->bc_ops = &xfs_rmapbt_ops;
+ cur->bc_nlevels = be32_to_cpu(agf->agf_levels[XFS_BTNUM_RMAP]);
+
+ cur->bc_private.a.agbp = agbp;
+ cur->bc_private.a.agno = agno;
+
+ return cur;
+}
+
+/*
+ * Calculate number of records in an rmap btree block.
+ */
+int
+xfs_rmapbt_maxrecs(
+ struct xfs_mount *mp,
+ int blocklen,
+ int leaf)
+{
+ blocklen -= XFS_RMAP_BLOCK_LEN;
+
+ if (leaf)
+ return blocklen / sizeof(struct xfs_rmap_rec);
+ return blocklen /
+ (sizeof(struct xfs_rmap_key) + sizeof(xfs_rmap_ptr_t));
+}
diff --git a/fs/xfs/libxfs/xfs_rmap_btree.h b/fs/xfs/libxfs/xfs_rmap_btree.h
index a3b8f90..2e02362 100644
--- a/fs/xfs/libxfs/xfs_rmap_btree.h
+++ b/fs/xfs/libxfs/xfs_rmap_btree.h
@@ -19,6 +19,37 @@
#define __XFS_RMAP_BTREE_H__

struct xfs_buf;
+struct xfs_btree_cur;
+struct xfs_mount;
+
+/* rmaps only exist on crc enabled filesystems */
+#define XFS_RMAP_BLOCK_LEN XFS_BTREE_SBLOCK_CRC_LEN
+
+/*
+ * Record, key, and pointer address macros for btree blocks.
+ *
+ * (note that some of these may appear unused, but they are used in userspace)
+ */
+#define XFS_RMAP_REC_ADDR(block, index) \
+ ((struct xfs_rmap_rec *) \
+ ((char *)(block) + XFS_RMAP_BLOCK_LEN + \
+ (((index) - 1) * sizeof(struct xfs_rmap_rec))))
+
+#define XFS_RMAP_KEY_ADDR(block, index) \
+ ((struct xfs_rmap_key *) \
+ ((char *)(block) + XFS_RMAP_BLOCK_LEN + \
+ ((index) - 1) * sizeof(struct xfs_rmap_key)))
+
+#define XFS_RMAP_PTR_ADDR(block, index, maxrecs) \
+ ((xfs_rmap_ptr_t *) \
+ ((char *)(block) + XFS_RMAP_BLOCK_LEN + \
+ (maxrecs) * sizeof(struct xfs_rmap_key) + \
+ ((index) - 1) * sizeof(xfs_rmap_ptr_t)))
+
+struct xfs_btree_cur *xfs_rmapbt_init_cursor(struct xfs_mount *mp,
+ struct xfs_trans *tp, struct xfs_buf *bp,
+ xfs_agnumber_t agno);
+int xfs_rmapbt_maxrecs(struct xfs_mount *mp, int blocklen, int leaf);

int xfs_rmap_alloc(struct xfs_trans *tp, struct xfs_buf *agbp,
xfs_agnumber_t agno, xfs_agblock_t bno, xfs_extlen_t len,
diff --git a/fs/xfs/libxfs/xfs_sb.c b/fs/xfs/libxfs/xfs_sb.c
index 8a53eaa..fadf750 100644
--- a/fs/xfs/libxfs/xfs_sb.c
+++ b/fs/xfs/libxfs/xfs_sb.c
@@ -36,6 +36,7 @@
#include "xfs_alloc_btree.h"
#include "xfs_ialloc_btree.h"
#include "xfs_log.h"
+#include "xfs_rmap_btree.h"

/*
* Physical superblock buffer manipulations. Shared with libxfs in userspace.
@@ -729,6 +730,11 @@ xfs_sb_mount_common(
mp->m_bmap_dmnr[0] = mp->m_bmap_dmxr[0] / 2;
mp->m_bmap_dmnr[1] = mp->m_bmap_dmxr[1] / 2;

+ mp->m_rmap_mxr[0] = xfs_rmapbt_maxrecs(mp, sbp->sb_blocksize, 1);
+ mp->m_rmap_mxr[1] = xfs_rmapbt_maxrecs(mp, sbp->sb_blocksize, 0);
+ mp->m_rmap_mnr[0] = mp->m_rmap_mxr[0] / 2;
+ mp->m_rmap_mnr[1] = mp->m_rmap_mxr[1] / 2;
+
mp->m_bsize = XFS_FSB_TO_BB(mp, 1);
mp->m_ialloc_inos = (int)MAX((__uint16_t)XFS_INODES_PER_CHUNK,
sbp->sb_inopblock);
diff --git a/fs/xfs/libxfs/xfs_shared.h b/fs/xfs/libxfs/xfs_shared.h
index 81ac870..4912072 100644
--- a/fs/xfs/libxfs/xfs_shared.h
+++ b/fs/xfs/libxfs/xfs_shared.h
@@ -38,6 +38,7 @@ extern const struct xfs_buf_ops xfs_agi_buf_ops;
extern const struct xfs_buf_ops xfs_agf_buf_ops;
extern const struct xfs_buf_ops xfs_agfl_buf_ops;
extern const struct xfs_buf_ops xfs_allocbt_buf_ops;
+extern const struct xfs_buf_ops xfs_rmapbt_buf_ops;
extern const struct xfs_buf_ops xfs_attr3_leaf_buf_ops;
extern const struct xfs_buf_ops xfs_attr3_rmt_buf_ops;
extern const struct xfs_buf_ops xfs_bmbt_buf_ops;
@@ -212,6 +213,7 @@ int xfs_log_calc_minimum_size(struct xfs_mount *);
#define XFS_INO_BTREE_REF 3
#define XFS_ALLOC_BTREE_REF 2
#define XFS_BMAP_BTREE_REF 2
+#define XFS_RMAP_BTREE_REF 2
#define XFS_DIR_BTREE_REF 2
#define XFS_INO_REF 2
#define XFS_ATTR_BTREE_REF 1
diff --git a/fs/xfs/xfs_mount.h b/fs/xfs/xfs_mount.h
index 9788686..b409a2a 100644
--- a/fs/xfs/xfs_mount.h
+++ b/fs/xfs/xfs_mount.h
@@ -90,6 +90,8 @@ typedef struct xfs_mount {
uint m_bmap_dmnr[2]; /* min bmap btree records */
uint m_inobt_mxr[2]; /* max inobt btree records */
uint m_inobt_mnr[2]; /* min inobt btree records */
+ uint m_rmap_mxr[2]; /* max rmap btree records */
+ uint m_rmap_mnr[2]; /* min rmap btree records */
uint m_ag_maxlevels; /* XFS_AG_MAXLEVELS */
uint m_bm_maxlevels[2]; /* XFS_BM_MAXLEVELS */
uint m_in_maxlevels; /* max inobt btree levels. */
diff --git a/fs/xfs/xfs_ondisk.h b/fs/xfs/xfs_ondisk.h
index 9a78408..07fb5d8 100644
--- a/fs/xfs/xfs_ondisk.h
+++ b/fs/xfs/xfs_ondisk.h
@@ -42,11 +42,14 @@ xfs_check_ondisk_structs(void)
XFS_CHECK_STRUCT_SIZE(struct xfs_dsymlink_hdr, 56);
XFS_CHECK_STRUCT_SIZE(struct xfs_inobt_key, 4);
XFS_CHECK_STRUCT_SIZE(struct xfs_inobt_rec, 16);
+ XFS_CHECK_STRUCT_SIZE(struct xfs_rmap_key, 20);
+ XFS_CHECK_STRUCT_SIZE(struct xfs_rmap_rec, 24);
XFS_CHECK_STRUCT_SIZE(struct xfs_timestamp, 8);
XFS_CHECK_STRUCT_SIZE(xfs_alloc_key_t, 8);
XFS_CHECK_STRUCT_SIZE(xfs_alloc_ptr_t, 4);
XFS_CHECK_STRUCT_SIZE(xfs_alloc_rec_t, 8);
XFS_CHECK_STRUCT_SIZE(xfs_inobt_ptr_t, 4);
+ XFS_CHECK_STRUCT_SIZE(xfs_rmap_ptr_t, 4);

/* dir/attr trees */
XFS_CHECK_STRUCT_SIZE(struct xfs_attr3_leaf_hdr, 80);