Re: [PATCH 4/7] xfs_db: dump dir/attr btrees

["Darrick J. Wong" <darrick.wong@oracle.com>]

On Mon, Jul 31, 2017 at 05:05:36PM -0500, Eric Sandeen wrote:
> On 7/31/17 4:07 PM, Darrick J. Wong wrote:
> > From: Darrick J. Wong <darrick.wong@oracle.com>
> > 
> > Dump the directory or extended attribute btree contents.
> > 
> > Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
> > ---
> >  db/btdump.c       |  251 +++++++++++++++++++++++++++++++++++++++++++++++++++++
> >  man/man8/xfs_db.8 |    1 
> >  2 files changed, 252 insertions(+)
> > 
> > 
> > diff --git a/db/btdump.c b/db/btdump.c
> > index 3b76e17..e351202 100644
> > --- a/db/btdump.c
> > +++ b/db/btdump.c
> > @@ -227,6 +227,252 @@ dump_inode(
> >  	return ret;
> >  }
> >  
> > +static bool
> > +dir_has_rightsib(
> > +	void				*block,
> > +	int				level)
> > +{
> > +	struct xfs_dir3_icleaf_hdr	lhdr;
> > +	struct xfs_da3_icnode_hdr	nhdr;
> > +
> > +	if (level > 0) {
> > +		M_DIROPS(mp)->node_hdr_from_disk(&nhdr, block);
> > +		return nhdr.forw != 0;
> > +	}
> > +	M_DIROPS(mp)->leaf_hdr_from_disk(&lhdr, block);
> > +	return lhdr.forw != 0;
> > +}
> > +
> > +static int
> > +dir_level(
> > +	void				*block)
> > +{
> > +	struct xfs_dir3_icleaf_hdr	lhdr;
> > +	struct xfs_da3_icnode_hdr	nhdr;
> > +
> > +	switch (((struct xfs_da_intnode *)block)->hdr.info.magic) {
> > +	case cpu_to_be16(XFS_DIR2_LEAF1_MAGIC):
> > +	case cpu_to_be16(XFS_DIR2_LEAFN_MAGIC):
> > +		M_DIROPS(mp)->leaf_hdr_from_disk(&lhdr, block);
> > +		return 0;
> > +	case cpu_to_be16(XFS_DA_NODE_MAGIC):
> > +		M_DIROPS(mp)->node_hdr_from_disk(&nhdr, block);
> > +		return nhdr.level;
> > +	default:
> > +		return -1;
> > +	}
> > +}
> > +
> > +static int
> > +dir3_level(
> > +	void				*block)
> > +{
> > +	struct xfs_dir3_icleaf_hdr	lhdr;
> > +	struct xfs_da3_icnode_hdr	nhdr;
> > +
> > +	switch (((struct xfs_da_intnode *)block)->hdr.info.magic) {
> > +	case cpu_to_be16(XFS_DIR3_LEAF1_MAGIC):
> > +	case cpu_to_be16(XFS_DIR3_LEAFN_MAGIC):
> > +		M_DIROPS(mp)->leaf_hdr_from_disk(&lhdr, block);
> > +		return 0;
> > +	case cpu_to_be16(XFS_DA3_NODE_MAGIC):
> > +		M_DIROPS(mp)->node_hdr_from_disk(&nhdr, block);
> > +		return nhdr.level;
> > +	default:
> > +		return -1;
> > +	}
> > +}
> > +
> > +static bool
> > +attr_has_rightsib(
> > +	void				*block,
> > +	int				level)
> > +{
> > +        struct xfs_attr_leafblock	lhdr;
> > +	struct xfs_da3_icnode_hdr	nhdr;
> > +
> > +	if (level > 0) {
> > +		M_DIROPS(mp)->node_hdr_from_disk(&nhdr, block);
> > +		return nhdr.forw != 0;
> > +	}
> > +	xfs_attr3_leaf_hdr_to_disk(mp->m_attr_geo, &lhdr, block);
> > +	return lhdr.hdr.info.forw != 0;
> > +}
> > +
> > +static int
> > +attr_level(
> > +	void				*block)
> > +{
> > +        struct xfs_attr_leafblock	lhdr;
> 
> funky whitespace
> 
> > +	struct xfs_da3_icnode_hdr	nhdr;
> > +
> > +	switch (((struct xfs_da_intnode *)block)->hdr.info.magic) {
> > +	case cpu_to_be16(XFS_ATTR_LEAF_MAGIC):
> > +		xfs_attr3_leaf_hdr_to_disk(mp->m_attr_geo, &lhdr, block);
> > +		return 0;
> > +	case cpu_to_be16(XFS_DA_NODE_MAGIC):
> > +		M_DIROPS(mp)->node_hdr_from_disk(&nhdr, block);
> > +		return nhdr.level;
> > +	default:
> > +		return -1;
> > +	}
> > +}
> > +
> > +static int
> > +attr3_level(
> > +	void				*block)
> > +{
> > +        struct xfs_attr_leafblock	lhdr;
> 
> ... again

Fixed both.

> > +	struct xfs_da3_icnode_hdr	nhdr;
> > +
> > +	switch (((struct xfs_da_intnode *)block)->hdr.info.magic) {
> > +	case cpu_to_be16(XFS_ATTR3_LEAF_MAGIC):
> > +		xfs_attr3_leaf_hdr_to_disk(mp->m_attr_geo, &lhdr, block);
> > +		return 0;
> > +	case cpu_to_be16(XFS_DA3_NODE_MAGIC):
> > +		M_DIROPS(mp)->node_hdr_from_disk(&nhdr, block);
> > +		return nhdr.level;
> > +	default:
> > +		return -1;
> > +	}
> > +}
> > +
> > +struct dabprinter {
> > +	const char		*print_node_entries;
> > +	const char		*print_leaf_entries;
> > +	const char		*go_node_forward;
> > +	const char		*go_leaf_forward;
> > +	const char		*go_down;
> > +	bool			(*has_rightsib)(void *, int);
> > +	int			(*level)(void *);
> > +};
> > +
> > +static struct dabprinter attr_print = {
> > +	.print_node_entries	= "btree",
> > +	.print_leaf_entries	= "entries nvlist",
> > +	.go_node_forward	= "hdr.info.forw",
> > +	.go_leaf_forward	= "hdr.info.forw",
> > +	.go_down		= "btree[0].before",
> > +	.has_rightsib		= attr_has_rightsib,
> > +	.level			= attr_level,
> > +};
> > +
> > +static struct dabprinter attr3_print = {
> > +	.print_node_entries	= "btree",
> > +	.print_leaf_entries	= "entries nvlist",
> > +	.go_node_forward	= "hdr.info.hdr.forw",
> > +	.go_leaf_forward	= "hdr.info.hdr.forw",
> > +	.go_down		= "btree[0].before",
> > +	.has_rightsib		= attr_has_rightsib,
> > +	.level			= attr3_level,
> > +};
> > +
> > +static struct dabprinter dir_print = {
> > +	.print_node_entries	= "nbtree",
> > +	.print_leaf_entries	= "lents",
> > +	.go_node_forward	= "nhdr.info.hdr.forw",
> > +	.go_leaf_forward	= "lhdr.info.hdr.forw",
> > +	.go_down		= "nbtree[0].before",
> > +	.has_rightsib		= dir_has_rightsib,
> > +	.level			= dir_level,
> > +};
> > +
> > +static struct dabprinter dir3_print = {
> > +	.print_node_entries	= "nbtree",
> > +	.print_leaf_entries	= "lents",
> > +	.go_node_forward	= "nhdr.info.forw",
> > +	.go_leaf_forward	= "lhdr.info.forw",
> > +	.go_down		= "nbtree[0].before",
> > +	.has_rightsib		= dir_has_rightsib,
> > +	.level			= dir3_level,
> > +};
> > +
> > +static int
> > +dump_dablevel(
> > +	int			level,
> > +	struct dabprinter	*dbp)
> > +{
> > +	xfs_daddr_t		orig_daddr = iocur_top->bb;
> > +	xfs_daddr_t		last_daddr;
> > +	unsigned int		nr;
> > +	int			ret;
> > +
> > +	ret = eval("push");
> 
> stupid question, is this different from simply push_cur()? 

Yes, we need set_cur() to finish initializing iocur_top.

> > +	if (ret)
> > +		return ret;
> > +
> > +	nr = 1;
> > +	do {
> > +		last_daddr = iocur_top->bb;
> > +		dbprintf(_("%s level %u block %u daddr %llu\n"),
> > +			 iocur_top->typ->name, level, nr, last_daddr);
> > +		ret = eval("print %s", level > 0 ? dbp->print_node_entries :
> > +						   dbp->print_leaf_entries);
> > +		if (ret)
> > +			goto err;
> > +		if (dbp->has_rightsib(iocur_top->data, level)) {
> > +			ret = eval("addr %s", level > 0 ? dbp->go_node_forward :
> > +							  dbp->go_leaf_forward);
> > +			if (ret)
> > +				goto err;
> > +		}
> > +		nr++;
> > +	} while (iocur_top->bb != orig_daddr && iocur_top->bb != last_daddr);
> > +
> > +	ret = eval("pop");
> > +	return ret;
> > +err:
> > +	eval("pop");
> > +	return ret;
> > +}
> > +
> > +static int
> > +dump_dabtree(
> > +	bool				dump_node_blocks,
> > +	struct dabprinter		*dbp)
> > +{
> > +	xfs_daddr_t			orig_daddr = iocur_top->bb;
> > +	xfs_daddr_t			last_daddr;
> > +	int				level;
> > +	int				ret;
> > +
> > +	ret = eval("push");
> > +	if (ret)
> > +		return ret;
> > +
> > +	cur_agno = XFS_FSB_TO_AGNO(mp, XFS_DADDR_TO_FSB(mp, iocur_top->bb));
> > +	level = dbp->level(iocur_top->data);
> > +	if (level < 0) {
> > +		printf(_("Current location is not part of a dir/attr btree.\n"));
> > +		goto err;
> > +	}
> > +
> > +	do {
> > +		last_daddr = iocur_top->bb;
> > +		if (level > 0) {
> > +			if (dump_node_blocks) {
> > +				ret = dump_dablevel(level, dbp);
> > +				if (ret)
> > +					goto err;
> > +			}
> > +			ret = eval("addr %s", dbp->go_down);
> > +		} else {
> > +			ret = dump_dablevel(level, dbp);
> > +		}
> > +		if (ret)
> > +			goto err;
> > +		level--;
> > +	} while (level >= 0 &&
> > +		 iocur_top->bb != orig_daddr &&
> > +		 iocur_top->bb != last_daddr);
> > +
> > +	ret = eval("pop");
> > +	return ret;
> > +err:
> > +	eval("pop");
> > +	return ret;
> > +}
> > +
> >  static int
> >  btdump_f(
> >  	int		argc,
> > @@ -234,6 +480,7 @@ btdump_f(
> >  {
> >  	bool		aflag = false;
> >  	bool		iflag = false;
> > +	bool		crc = xfs_sb_version_hascrc(&mp->m_sb);
> >  	int		c;
> >  
> >  	if (cur_typ == NULL) {
> > @@ -276,6 +523,10 @@ btdump_f(
> >  		return dump_btree_long(iflag);
> >  	case TYP_INODE:
> >  		return dump_inode(iflag, aflag);
> > +	case TYP_ATTR:
> > +		return dump_dabtree(iflag, crc ? &attr3_print : &attr_print);
> > +	case TYP_DIR2:
> > +		return dump_dabtree(iflag, crc ? &dir3_print : &dir_print);
> >  	default:
> >  		dbprintf(_("type \"%s\" is not a btree type or inode\n"),
> >  				cur_typ->name);
> > diff --git a/man/man8/xfs_db.8 b/man/man8/xfs_db.8
> > index 6a97504..b3129f7 100644
> > --- a/man/man8/xfs_db.8
> > +++ b/man/man8/xfs_db.8
> > @@ -335,6 +335,7 @@ area of the inode, if neither option is given then both areas are shown.
> >  .B btdump [-a] [-i]
> >  If the cursor points to a btree node, dump the btree from that block downward.
> >  If instead the cursor points to an inode, dump the data fork block mapping btree if there is one.
> > +If the cursor points to a directory or extended attribute btree node, dump that.
> >  By default, only records stored in the btree are dumped.
> 
> adding this to the command long help would be nice too
> 
> xfs_db> help btdump
> btdump [-a] [-i] -- dump btree
> 
>  If the cursor points to a btree block, 'btdump' dumps the btree
>  downward from that block.  If the cursor points to an inode,
>  the data fork btree root is selected by default.
> 
>  Options:
>    -a -- Display an inode's extended attribute fork btree.
>    -i -- Print internal btree nodes.

Will do.

--D

> 
> 
> 
> >  .RS 1.0i
> >  .TP 0.4i
> > 
> 
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