[PATCH 054/119] xfs: introduce refcount btree definitions

Darrick J. Wong
2016-06-17T01:23:49Z

Add new per-AG refcount btree definitions to the per-AG structures.

v2: Move the reflink inode flag out of the way of the DAX flag, and
add the new cowextsize flag.

v3: Don't allow pNFS to export reflinked files; this will be removed
some day when the Linux pNFS server supports it.

[hch: don't allow pNFS export of reflinked files]
[darrick: fix the feature test in hch's patch]

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
fs/xfs/libxfs/xfs_alloc.c | 5 +++++
fs/xfs/libxfs/xfs_btree.c | 5 +++--
fs/xfs/libxfs/xfs_btree.h | 3 +++
fs/xfs/libxfs/xfs_format.h | 29 ++++++++++++++++++++++++++---
fs/xfs/libxfs/xfs_rmap_btree.c | 7 +++++--
fs/xfs/libxfs/xfs_types.h | 2 +-
fs/xfs/xfs_inode.h | 5 +++++
fs/xfs/xfs_mount.h | 3 +++
fs/xfs/xfs_pnfs.c | 7 +++++++
9 files changed, 58 insertions(+), 8 deletions(-)

diff --git a/fs/xfs/libxfs/xfs_alloc.c b/fs/xfs/libxfs/xfs_alloc.c
index 5f05c4e..9009b1f 100644
--- a/fs/xfs/libxfs/xfs_alloc.c
+++ b/fs/xfs/libxfs/xfs_alloc.c
@@ -2448,6 +2448,10 @@ xfs_agf_verify(
be32_to_cpu(agf->agf_btreeblks) > be32_to_cpu(agf->agf_length))
return false;

+ if (xfs_sb_version_hasreflink(&mp->m_sb) &&
+ be32_to_cpu(agf->agf_refcount_level) > XFS_BTREE_MAXLEVELS)
+ return false;
+
return true;;

}
@@ -2568,6 +2572,7 @@ xfs_alloc_read_agf(
be32_to_cpu(agf->agf_levels[XFS_BTNUM_CNTi]);
pag->pagf_levels[XFS_BTNUM_RMAPi] =
be32_to_cpu(agf->agf_levels[XFS_BTNUM_RMAPi]);
+ pag->pagf_refcount_level = be32_to_cpu(agf->agf_refcount_level);
spin_lock_init(&pag->pagb_lock);
pag->pagb_count = 0;
#ifdef __KERNEL__
diff --git a/fs/xfs/libxfs/xfs_btree.c b/fs/xfs/libxfs/xfs_btree.c
index 50b2c32..1593239 100644
--- a/fs/xfs/libxfs/xfs_btree.c
+++ b/fs/xfs/libxfs/xfs_btree.c
@@ -45,9 +45,10 @@ kmem_zone_t *xfs_btree_cur_zone;
*/
static const __uint32_t xfs_magics[2][XFS_BTNUM_MAX] = {
{ XFS_ABTB_MAGIC, XFS_ABTC_MAGIC, 0, XFS_BMAP_MAGIC, XFS_IBT_MAGIC,
- XFS_FIBT_MAGIC },
+ XFS_FIBT_MAGIC, 0 },
{ XFS_ABTB_CRC_MAGIC, XFS_ABTC_CRC_MAGIC, XFS_RMAP_CRC_MAGIC,
- XFS_BMAP_CRC_MAGIC, XFS_IBT_CRC_MAGIC, XFS_FIBT_CRC_MAGIC }
+ XFS_BMAP_CRC_MAGIC, XFS_IBT_CRC_MAGIC, XFS_FIBT_CRC_MAGIC,
+ XFS_REFC_CRC_MAGIC }
};
#define xfs_btree_magic(cur) \
xfs_magics[!!((cur)->bc_flags & XFS_BTREE_CRC_BLOCKS)][cur->bc_btnum]
diff --git a/fs/xfs/libxfs/xfs_btree.h b/fs/xfs/libxfs/xfs_btree.h
index 6fa13a9..9b5a921 100644
--- a/fs/xfs/libxfs/xfs_btree.h
+++ b/fs/xfs/libxfs/xfs_btree.h
@@ -66,6 +66,7 @@ union xfs_btree_rec {
#define XFS_BTNUM_INO ((xfs_btnum_t)XFS_BTNUM_INOi)
#define XFS_BTNUM_FINO ((xfs_btnum_t)XFS_BTNUM_FINOi)
#define XFS_BTNUM_RMAP ((xfs_btnum_t)XFS_BTNUM_RMAPi)
+#define XFS_BTNUM_REFC ((xfs_btnum_t)XFS_BTNUM_REFCi)

/*
* For logging record fields.
@@ -99,6 +100,7 @@ do { \
case XFS_BTNUM_INO: __XFS_BTREE_STATS_INC(__mp, ibt, stat); break; \
case XFS_BTNUM_FINO: __XFS_BTREE_STATS_INC(__mp, fibt, stat); break; \
case XFS_BTNUM_RMAP: __XFS_BTREE_STATS_INC(__mp, rmap, stat); break; \
+ case XFS_BTNUM_REFC: break; \
case XFS_BTNUM_MAX: ASSERT(0); __mp = __mp /* fucking gcc */ ; break; \
} \
} while (0)
@@ -121,6 +123,7 @@ do { \
__XFS_BTREE_STATS_ADD(__mp, fibt, stat, val); break; \
case XFS_BTNUM_RMAP: \
__XFS_BTREE_STATS_ADD(__mp, rmap, stat, val); break; \
+ case XFS_BTNUM_REFC: break; \
case XFS_BTNUM_MAX: ASSERT(0); __mp = __mp /* fucking gcc */ ; break; \
} \
} while (0)
diff --git a/fs/xfs/libxfs/xfs_format.h b/fs/xfs/libxfs/xfs_format.h
index 1b08237..63a97a9 100644
--- a/fs/xfs/libxfs/xfs_format.h
+++ b/fs/xfs/libxfs/xfs_format.h
@@ -456,6 +456,7 @@ xfs_sb_has_compat_feature(

#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_ALL \
(XFS_SB_FEAT_RO_COMPAT_FINOBT | \
XFS_SB_FEAT_RO_COMPAT_RMAPBT)
@@ -546,6 +547,12 @@ static inline bool xfs_sb_version_hasrmapbt(struct xfs_sb *sbp)
(sbp->sb_features_ro_compat & XFS_SB_FEAT_RO_COMPAT_RMAPBT);
}

+static inline bool xfs_sb_version_hasreflink(struct xfs_sb *sbp)
+{
+ return (XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5) &&
+ (sbp->sb_features_ro_compat & XFS_SB_FEAT_RO_COMPAT_REFLINK);
+}
+
/*
* end of superblock version macros
*/
@@ -640,12 +647,15 @@ typedef struct xfs_agf {
__be32 agf_btreeblks; /* # of blocks held in AGF btrees */
uuid_t agf_uuid; /* uuid of filesystem */

+ __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[16];
+ __be64 agf_spare64[15];

/* unlogged fields, written during buffer writeback. */
__be64 agf_lsn; /* last write sequence */
@@ -1033,9 +1043,14 @@ static inline void xfs_dinode_put_rdev(struct xfs_dinode *dip, xfs_dev_t rdev)
* 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_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_ANY (XFS_DIFLAG2_DAX)
+#define XFS_DIFLAG2_ANY \
+ (XFS_DIFLAG2_DAX | XFS_DIFLAG2_REFLINK | XFS_DIFLAG2_COWEXTSIZE)

/*
* Inode number format:
@@ -1382,7 +1397,8 @@ xfs_rmap_ino_owner(
#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_MIN (-8ULL) /* guard */
+#define XFS_RMAP_OWN_REFC (-8ULL) /* refcount tree */
+#define XFS_RMAP_OWN_MIN (-9ULL) /* guard */

#define XFS_RMAP_NON_INODE_OWNER(owner) (!!((owner) & (1ULL << 63)))

@@ -1530,6 +1546,13 @@ xfs_owner_info_pack(
}

/*
+ * Reference Count Btree format definitions
+ *
+ */
+#define XFS_REFC_CRC_MAGIC 0x52334643 /* 'R3FC' */
+
+
+/*
* BMAP Btree format definitions
*
* This includes both the root block definition that sits inside an inode fork
diff --git a/fs/xfs/libxfs/xfs_rmap_btree.c b/fs/xfs/libxfs/xfs_rmap_btree.c
index 9adb930..090dbbe 100644
--- a/fs/xfs/libxfs/xfs_rmap_btree.c
+++ b/fs/xfs/libxfs/xfs_rmap_btree.c
@@ -475,6 +475,9 @@ void
xfs_rmapbt_compute_maxlevels(
struct xfs_mount *mp)
{
- mp->m_rmap_maxlevels = xfs_btree_compute_maxlevels(mp,
- mp->m_rmap_mnr, mp->m_sb.sb_agblocks);
+ if (xfs_sb_version_hasreflink(&mp->m_sb))
+ mp->m_rmap_maxlevels = XFS_BTREE_MAXLEVELS;
+ else
+ mp->m_rmap_maxlevels = xfs_btree_compute_maxlevels(mp,
+ mp->m_rmap_mnr, mp->m_sb.sb_agblocks);
}
diff --git a/fs/xfs/libxfs/xfs_types.h b/fs/xfs/libxfs/xfs_types.h
index da87796..690d616 100644
--- a/fs/xfs/libxfs/xfs_types.h
+++ b/fs/xfs/libxfs/xfs_types.h
@@ -112,7 +112,7 @@ typedef enum {

typedef enum {
XFS_BTNUM_BNOi, XFS_BTNUM_CNTi, XFS_BTNUM_RMAPi, XFS_BTNUM_BMAPi,
- XFS_BTNUM_INOi, XFS_BTNUM_FINOi, XFS_BTNUM_MAX
+ XFS_BTNUM_INOi, XFS_BTNUM_FINOi, XFS_BTNUM_REFCi, XFS_BTNUM_MAX
} xfs_btnum_t;

struct xfs_name {
diff --git a/fs/xfs/xfs_inode.h b/fs/xfs/xfs_inode.h
index 633f2af..d0ea6ff 100644
--- a/fs/xfs/xfs_inode.h
+++ b/fs/xfs/xfs_inode.h
@@ -202,6 +202,11 @@ xfs_get_initial_prid(struct xfs_inode *dp)
return XFS_PROJID_DEFAULT;
}

+static inline bool xfs_is_reflink_inode(struct xfs_inode *ip)
+{
+ return ip->i_d.di_flags2 & XFS_DIFLAG2_REFLINK;
+}
+
/*
* In-core inode flags.
*/
diff --git a/fs/xfs/xfs_mount.h b/fs/xfs/xfs_mount.h
index e18d74e..823ee63 100644
--- a/fs/xfs/xfs_mount.h
+++ b/fs/xfs/xfs_mount.h
@@ -391,6 +391,9 @@ typedef struct xfs_perag {
struct xfs_ag_resv pag_meta_resv;
/* Blocks reserved for just AGFL-based metadata. */
struct xfs_ag_resv pag_agfl_resv;
+
+ /* reference count */
+ __uint8_t pagf_refcount_level;
} xfs_perag_t;

static inline struct xfs_ag_resv *
diff --git a/fs/xfs/xfs_pnfs.c b/fs/xfs/xfs_pnfs.c
index d5b7566..b21f532 100644
--- a/fs/xfs/xfs_pnfs.c
+++ b/fs/xfs/xfs_pnfs.c
@@ -139,6 +139,13 @@ xfs_fs_map_blocks(
return -ENXIO;

/*
+ * The pNFS block layout spec actually supports reflink like
+ * functionality, but the Linux pNFS server doesn't implement it yet.
+ */
+ if (xfs_is_reflink_inode(ip))
+ return -ENXIO;
+
+ /*
* Lock out any other I/O before we flush and invalidate the pagecache,
* and then hand out a layout to the remote system. This is very
* similar to direct I/O, except that the synchronization is much more