From 177c81e25b763c90f9815b1f4055d9d5c515a845 Mon Sep 17 00:00:00 2001

From: "Darrick J. Wong" <darrick.wong@oracle.com>

Date: Tue, 10 Nov 2020 15:11:09 -0500

Subject: [PATCH] xfs: store inode btree block counts in AGI header

Source kernel commit: 2a39946c984464e4aac82c556ba9915589be7323

Add a btree block usage counters for both inode btrees to the AGI header

so that we don't have to walk the entire finobt at mount time to create

the per-AG reservations.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

Reviewed-by: Brian Foster <bfoster@redhat.com>

Signed-off-by: Eric Sandeen <sandeen@sandeen.net>

---

NOTE: kernel routines are not used to initialize AGIs in this

version, so I added to the open-coded function in xfs_mkfs.c

diff --git a/libxfs/xfs_ag.c b/libxfs/xfs_ag.c

index a7d1a0d..850d6e3 100644

--- a/libxfs/xfs_ag.c

+++ b/libxfs/xfs_ag.c

@@ -258,6 +258,11 @@ xfs_agiblock_init(

 	}

 	for (bucket = 0; bucket < XFS_AGI_UNLINKED_BUCKETS; bucket++)

 		agi->agi_unlinked[bucket] = cpu_to_be32(NULLAGINO);

+	if (xfs_sb_version_hasinobtcounts(&mp->m_sb)) {

+		agi->agi_iblocks = cpu_to_be32(1);

+		if (xfs_sb_version_hasfinobt(&mp->m_sb))

+			agi->agi_fblocks = cpu_to_be32(1);

+	}

 }

 typedef void (*aghdr_init_work_f)(struct xfs_mount *mp, struct xfs_buf *bp,

diff --git a/libxfs/xfs_format.h b/libxfs/xfs_format.h

index 23eca3b..7f7b03a 100644

--- a/libxfs/xfs_format.h

+++ b/libxfs/xfs_format.h

@@ -449,6 +449,7 @@ 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_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 | \

@@ -546,6 +547,17 @@ static inline bool xfs_sb_version_hasreflink(struct xfs_sb *sbp)

 		(sbp->sb_features_ro_compat & XFS_SB_FEAT_RO_COMPAT_REFLINK);

 }

+/*

+ * Inode btree block counter.  We record the number of inobt and finobt blocks

+ * in the AGI header so that we can skip the finobt walk at mount time when

+ * setting up per-AG reservations.

+ */

+static inline bool xfs_sb_version_hasinobtcounts(struct xfs_sb *sbp)

+{

+	return XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5 &&

+		(sbp->sb_features_ro_compat & XFS_SB_FEAT_RO_COMPAT_INOBTCNT);

+}

+

 /*

  * end of superblock version macros

  */

@@ -750,6 +762,9 @@ typedef struct xfs_agi {

 	__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;

@@ -770,7 +785,8 @@ typedef struct xfs_agi {

 #define	XFS_AGI_ALL_BITS_R1	((1 << XFS_AGI_NUM_BITS_R1) - 1)

 #define	XFS_AGI_FREE_ROOT	(1 << 11)

 #define	XFS_AGI_FREE_LEVEL	(1 << 12)

-#define	XFS_AGI_NUM_BITS_R2	13

+#define	XFS_AGI_IBLOCKS		(1 << 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))

diff --git a/libxfs/xfs_ialloc.c b/libxfs/xfs_ialloc.c

index a600c03..9d380f9 100644

--- a/libxfs/xfs_ialloc.c

+++ b/libxfs/xfs_ialloc.c

@@ -2451,6 +2451,7 @@ xfs_ialloc_log_agi(

 		offsetof(xfs_agi_t, agi_unlinked),

 		offsetof(xfs_agi_t, agi_free_root),

 		offsetof(xfs_agi_t, agi_free_level),

+		offsetof(xfs_agi_t, agi_iblocks),

 		sizeof(xfs_agi_t)

 	};

 #ifdef DEBUG

diff --git a/libxfs/xfs_ialloc_btree.c b/libxfs/xfs_ialloc_btree.c

index 716a81f..9db87e9 100644

--- a/libxfs/xfs_ialloc_btree.c

+++ b/libxfs/xfs_ialloc_btree.c

@@ -68,6 +68,25 @@ xfs_finobt_set_root(

 			   XFS_AGI_FREE_ROOT | XFS_AGI_FREE_LEVEL);

 }

+/* Update the inode btree block counter for this btree. */

+static inline void

+xfs_inobt_mod_blockcount(

+	struct xfs_btree_cur	*cur,

+	int			howmuch)

+{

+	struct xfs_buf		*agbp = cur->bc_private.a.agbp;

+	struct xfs_agi		*agi = agbp->b_addr;

+

+	if (!xfs_sb_version_hasinobtcounts(&cur->bc_mp->m_sb))

+		return;

+

+	if (cur->bc_btnum == XFS_BTNUM_FINO)

+		be32_add_cpu(&agi->agi_fblocks, howmuch);

+	else if (cur->bc_btnum == XFS_BTNUM_INO)

+		be32_add_cpu(&agi->agi_iblocks, howmuch);

+	xfs_ialloc_log_agi(cur->bc_tp, agbp, XFS_AGI_IBLOCKS);

+}

+

 STATIC int

 __xfs_inobt_alloc_block(

 	struct xfs_btree_cur	*cur,

@@ -103,6 +122,7 @@ __xfs_inobt_alloc_block(

 	new->s = cpu_to_be32(XFS_FSB_TO_AGBNO(args.mp, args.fsbno));

 	*stat = 1;

+	xfs_inobt_mod_blockcount(cur, 1);

 	return 0;

 }

@@ -135,6 +155,7 @@ __xfs_inobt_free_block(

 	struct xfs_buf		*bp,

 	enum xfs_ag_resv_type	resv)

 {

+	xfs_inobt_mod_blockcount(cur, -1);

 	return xfs_free_extent(cur->bc_tp,

 			XFS_DADDR_TO_FSB(cur->bc_mp, XFS_BUF_ADDR(bp)), 1,

 			&XFS_RMAP_OINFO_INOBT, resv);

diff --git a/mkfs/xfs_mkfs.c b/mkfs/xfs_mkfs.c

index 16819d8..992224d 100644

--- a/mkfs/xfs_mkfs.c

+++ b/mkfs/xfs_mkfs.c

@@ -3588,6 +3588,11 @@ initialise_ag_headers(

 		platform_uuid_copy(&agi->agi_uuid, &sbp->sb_uuid);

 	for (c = 0; c < XFS_AGI_UNLINKED_BUCKETS; c++)

 		agi->agi_unlinked[c] = cpu_to_be32(NULLAGINO);

+	if (xfs_sb_version_hasinobtcounts(&mp->m_sb)) {

+		agi->agi_iblocks = cpu_to_be32(1);

+		if (xfs_sb_version_hasfinobt(&mp->m_sb))

+			agi->agi_fblocks = cpu_to_be32(1);

+	}

 	libxfs_writebuf(buf, LIBXFS_EXIT_ON_FAILURE);

 	/*