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mkfs: set agblklog when we're verifying minimum log size

PATCH In review Darrick J. Wong 2 participants 4 messages Jul 7, 2017

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#0 lore raw

PATCH 1/1 mkfs: set agblklog when we're verifying minimum log size

In e5cc9d560a ("mkfs: set agsize prior to calculating minimum log size"), we set the ag size in the superblock structure so that we can calculate the maximum btree height correctly. The btree heights are used to calculate transaction reservation sizes; these sizes are used to compute the minimum log length; and the minimum log length is checked by the kernel.

Unfortunately, I didn't realize that some of the btree sizing functions also depend on the agblklog (log2 of the ag size), so we've been underestimating the minimum log length allowable, which results in mkfs formatting filesystems that the kernel refuses to mount.

This can be trivially reproduced by formatting a small (~800M) volume with rmap and reflink turned on.

---
 mkfs/maxtrres.c |    1 +
 1 file changed, 1 insertion(+)
mkfs/maxtrres.c +1 -0
index fba7818..69ec67a 100644
@@ -54,6 +54,7 @@ max_trans_res(
 	sbp->sb_blocklog = blocklog;
 	sbp->sb_blocksize = 1 << blocklog;
 	sbp->sb_agblocks = agsize;
+	sbp->sb_agblklog = (uint8_t)libxfs_log2_roundup((unsigned int)agsize);
 	sbp->sb_inodelog = inodelog;
 	sbp->sb_inopblog = blocklog - inodelog;
 	sbp->sb_inodesize = 1 << inodelog;
#1 lore raw

PATCH 1/1 mkfs: set inode alignment and cluster size for minimum log size estimation

In order for mkfs to calculate the minimum log size correctly, it must be able to find the transaction type with the largest reservation. The iunlink transaction reservation size calculation depends on having the inode cluster size set correctly, which in turn depends on the inode alignment parameters being set as they will be in the final filesystem. Therefore we have to set up the inoalignmt field in max_trans_res.

---
 include/xfs_multidisk.h |    2 +-
 libxfs/init.c           |    7 +++++++
 mkfs/maxtrres.c         |   10 +++++++++-
 mkfs/xfs_mkfs.c         |    3 ++-
 4 files changed, 19 insertions(+), 3 deletions(-)
include/xfs_multidisk.h +1 -1
index ce9bbce..e5f53b7 100644
@@ -69,6 +69,6 @@ extern void res_failed (int err);
 extern int max_trans_res(unsigned long agsize, int crcs_enabled, int dirversion,
 		int sectorlog, int blocklog, int inodelog, int dirblocklog,
 		int logversion, int log_sunit, int finobt, int rmapbt,
-		int reflink);
+		int reflink, int inode_align);
 
 #endif	/* __XFS_MULTIDISK_H__ */
libxfs/init.c +7 -0
index 3fb0fdf..d77a9e6 100644
@@ -707,6 +707,13 @@ libxfs_mount(
 		mp->m_maxicount = 0;
 
 	mp->m_inode_cluster_size = XFS_INODE_BIG_CLUSTER_SIZE;
+	if (xfs_sb_version_hascrc(&mp->m_sb)) {
+		int	new_size = mp->m_inode_cluster_size;
+
+		new_size *= mp->m_sb.sb_inodesize / XFS_DINODE_MIN_SIZE;
+		if (mp->m_sb.sb_inoalignmt >= XFS_B_TO_FSBT(mp, new_size))
+			mp->m_inode_cluster_size = new_size;
+	}
 
 	/*
 	 * Set whether we're using stripe alignment.
mkfs/maxtrres.c +9 -1
index 69ec67a..04028bf 100644
@@ -40,7 +40,8 @@ max_trans_res(
 	int		log_sunit,
 	int		finobt,
 	int		rmapbt,
-	int		reflink)
+	int		reflink,
+	int		inode_align)
 {
 	xfs_sb_t	*sbp;
 	xfs_mount_t	mount;
@@ -61,6 +62,13 @@ max_trans_res(
 	sbp->sb_inopblock = 1 << (blocklog - inodelog);
 	sbp->sb_dirblklog = dirblocklog - blocklog;
 
+	if (inode_align) {
+		int	cluster_size = XFS_INODE_BIG_CLUSTER_SIZE;
+		if (crcs_enabled)
+			cluster_size *= sbp->sb_inodesize / XFS_DINODE_MIN_SIZE;
+		sbp->sb_inoalignmt = cluster_size >> blocklog;
+	}
+
 	if (log_sunit > 0) {
 		log_sunit <<= blocklog;
 		logversion = 2;
mkfs/xfs_mkfs.c +2 -1
index c839936..faa0e9a 100644
@@ -2612,7 +2612,8 @@ an AG size that is one stripe unit smaller, for example %llu.\n"),
 				   sb_feat.crcs_enabled, sb_feat.dir_version,
 				   sectorlog, blocklog, inodelog, dirblocklog,
 				   sb_feat.log_version, lsunit, sb_feat.finobt,
-				   sb_feat.rmapbt, sb_feat.reflink);
+				   sb_feat.rmapbt, sb_feat.reflink,
+				   sb_feat.inode_align);
 	ASSERT(min_logblocks);
 	min_logblocks = MAX(XFS_MIN_LOG_BLOCKS, min_logblocks);
 	if (!logsize && dblocks >= (1024*1024*1024) >> blocklog)
Reviewed-by on v1 1/1
#2 lore raw

Re: [PATCH] mkfs: set inode alignment and cluster size for minimum log size estimation

Quoted 9 lines · Darrick J. Wong

In order for mkfs to calculate the minimum log size correctly, it must be able to find the transaction type with the largest reservation. The iunlink transaction reservation size calculation depends on having the inode cluster size set correctly, which in turn depends on the inode alignment parameters being set as they will be in the final filesystem. Therefore we have to set up the inoalignmt field in max_trans_res.

---

Quoted 82 lines
 include/xfs_multidisk.h |    2 +-
 libxfs/init.c           |    7 +++++++
 mkfs/maxtrres.c         |   10 +++++++++-
 mkfs/xfs_mkfs.c         |    3 ++-
 4 files changed, 19 insertions(+), 3 deletions(-)
include/xfs_multidisk.h +1 -1
index ce9bbce..e5f53b7 100644
@@ -69,6 +69,6 @@ extern void res_failed (int err);
 extern int max_trans_res(unsigned long agsize, int crcs_enabled, int dirversion,
 		int sectorlog, int blocklog, int inodelog, int dirblocklog,
 		int logversion, int log_sunit, int finobt, int rmapbt,
-		int reflink);
+		int reflink, int inode_align);
 
 #endif	/* __XFS_MULTIDISK_H__ */
libxfs/init.c +7 -0
index 3fb0fdf..d77a9e6 100644
@@ -707,6 +707,13 @@ libxfs_mount(
 		mp->m_maxicount = 0;
 
 	mp->m_inode_cluster_size = XFS_INODE_BIG_CLUSTER_SIZE;
+	if (xfs_sb_version_hascrc(&mp->m_sb)) {
+		int	new_size = mp->m_inode_cluster_size;
+
+		new_size *= mp->m_sb.sb_inodesize / XFS_DINODE_MIN_SIZE;
+		if (mp->m_sb.sb_inoalignmt >= XFS_B_TO_FSBT(mp, new_size))
+			mp->m_inode_cluster_size = new_size;
+	}
 
 	/*
 	 * Set whether we're using stripe alignment.
mkfs/maxtrres.c +9 -1
index 69ec67a..04028bf 100644
@@ -40,7 +40,8 @@ max_trans_res(
 	int		log_sunit,
 	int		finobt,
 	int		rmapbt,
-	int		reflink)
+	int		reflink,
+	int		inode_align)
 {
 	xfs_sb_t	*sbp;
 	xfs_mount_t	mount;
@@ -61,6 +62,13 @@ max_trans_res(
 	sbp->sb_inopblock = 1 << (blocklog - inodelog);
 	sbp->sb_dirblklog = dirblocklog - blocklog;
 
+	if (inode_align) {
+		int	cluster_size = XFS_INODE_BIG_CLUSTER_SIZE;
+		if (crcs_enabled)
+			cluster_size *= sbp->sb_inodesize / XFS_DINODE_MIN_SIZE;
+		sbp->sb_inoalignmt = cluster_size >> blocklog;
+	}
+
 	if (log_sunit > 0) {
 		log_sunit <<= blocklog;
 		logversion = 2;
mkfs/xfs_mkfs.c +2 -2
index c839936..faa0e9a 100644
@@ -2612,7 +2612,8 @@ an AG size that is one stripe unit smaller, for example %llu.\n"),
 				   sb_feat.crcs_enabled, sb_feat.dir_version,
 				   sectorlog, blocklog, inodelog, dirblocklog,
 				   sb_feat.log_version, lsunit, sb_feat.finobt,
-				   sb_feat.rmapbt, sb_feat.reflink);
+				   sb_feat.rmapbt, sb_feat.reflink,
+				   sb_feat.inode_align);
 	ASSERT(min_logblocks);
 	min_logblocks = MAX(XFS_MIN_LOG_BLOCKS, min_logblocks);
 	if (!logsize && dblocks >= (1024*1024*1024) >> blocklog)
--

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Reviewed-by on v1 1/1
#3 lore raw
In reply to Darrick J. Wong
Quoted 12 lines · Darrick J. Wong

In e5cc9d560a ("mkfs: set agsize prior to calculating minimum log size"), we set the ag size in the superblock structure so that we can calculate the maximum btree height correctly. The btree heights are used to calculate transaction reservation sizes; these sizes are used to compute the minimum log length; and the minimum log length is checked by the kernel.

Unfortunately, I didn't realize that some of the btree sizing functions also depend on the agblklog (log2 of the ag size), so we've been underestimating the minimum log length allowable, which results in mkfs formatting filesystems that the kernel refuses to mount.

Quoted 5 lines

This can be trivially reproduced by formatting a small (~800M) volume with rmap and reflink turned on.

---

Quoted 19 lines
 mkfs/maxtrres.c |    1 +
 1 file changed, 1 insertion(+)
mkfs/maxtrres.c +1 -1
index fba7818..69ec67a 100644
@@ -54,6 +54,7 @@ max_trans_res(
 	sbp->sb_blocklog = blocklog;
 	sbp->sb_blocksize = 1 << blocklog;
 	sbp->sb_agblocks = agsize;
+	sbp->sb_agblklog = (uint8_t)libxfs_log2_roundup((unsigned int)agsize);
 	sbp->sb_inodelog = inodelog;
 	sbp->sb_inopblog = blocklog - inodelog;
 	sbp->sb_inodesize = 1 << inodelog;
--

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