Re: [PATCH 1/2] xfs_db: add a directory path lookup command

Darrick J. Wong
2021-01-20T18:46:25Z

On Wed, Jan 20, 2021 at 06:05:35PM +0530, Chandan Babu R wrote:
>
> On 16 Jan 2021 at 06:54, Darrick J. Wong wrote:
> > From: Darrick J. Wong <djwong@kernel.org>
> >
> > Add a command to xfs_db so that we can navigate to inodes by path.
> >
> > Signed-off-by: Darrick J. Wong <djwong@kernel.org>
> > ---
> > db/Makefile | 3 -
> > db/command.c | 1
> > db/command.h | 1
> > db/namei.c | 223 +++++++++++++++++++++++++++++++++++++++++++++++++++++
> > man/man8/xfs_db.8 | 4 +
> > 5 files changed, 231 insertions(+), 1 deletion(-)
> > create mode 100644 db/namei.c
> >
> >
> > diff --git a/db/Makefile b/db/Makefile
> > index 9d502bf0..beafb105 100644
> > --- a/db/Makefile
> > +++ b/db/Makefile
> > @@ -14,7 +14,8 @@ HFILES = addr.h agf.h agfl.h agi.h attr.h attrshort.h bit.h block.h bmap.h \
> > io.h logformat.h malloc.h metadump.h output.h print.h quit.h sb.h \
> > sig.h strvec.h text.h type.h write.h attrset.h symlink.h fsmap.h \
> > fuzz.h
> > -CFILES = $(HFILES:.h=.c) btdump.c btheight.c convert.c info.c timelimit.c
> > +CFILES = $(HFILES:.h=.c) btdump.c btheight.c convert.c info.c namei.c \
> > + timelimit.c
> > LSRCFILES = xfs_admin.sh xfs_ncheck.sh xfs_metadump.sh
> >
> > LLDLIBS = $(LIBXFS) $(LIBXLOG) $(LIBFROG) $(LIBUUID) $(LIBRT) $(LIBPTHREAD)
> > diff --git a/db/command.c b/db/command.c
> > index 43828369..02f778b9 100644
> > --- a/db/command.c
> > +++ b/db/command.c
> > @@ -131,6 +131,7 @@ init_commands(void)
> > logformat_init();
> > io_init();
> > metadump_init();
> > + namei_init();
> > output_init();
> > print_init();
> > quit_init();
> > diff --git a/db/command.h b/db/command.h
> > index 6913c817..498983ff 100644
> > --- a/db/command.h
> > +++ b/db/command.h
> > @@ -33,3 +33,4 @@ extern void btdump_init(void);
> > extern void info_init(void);
> > extern void btheight_init(void);
> > extern void timelimit_init(void);
> > +extern void namei_init(void);
> > diff --git a/db/namei.c b/db/namei.c
> > new file mode 100644
> > index 00000000..eebebe15
> > --- /dev/null
> > +++ b/db/namei.c
> > @@ -0,0 +1,223 @@

<snip some of this out>

> > +/* Walk a directory path to an inode and set the io cursor to that inode. */
> > +static int
> > +path_walk(
> > + char *path)
> > +{
> > + struct dirpath *dirpath;
> > + char *p = path;
> > + xfs_ino_t rootino = mp->m_sb.sb_rootino;
> > + int error = 0;
> > +
> > + if (*p == '/') {
> > + /* Absolute path, start from the root inode. */
> > + p++;
> > + } else {
> > + /* Relative path, start from current dir. */
> > + if (iocur_top->typ != &typtab[TYP_INODE] ||
> > + !S_ISDIR(iocur_top->mode))
> > + return ENOTDIR;
> > +
> > + rootino = iocur_top->ino;
> > + }
> > +
> > + dirpath = path_parse(p);
> > + if (!dirpath)
> > + return ENOMEM;
> > +
> > + error = path_navigate(mp, rootino, dirpath);
> > + if (error)
> > + return error;
>
> Memory pointed by dirpath (and its members) is not freed if the call to
> path_navigate() returns a non-zero error value.

Good catch, thanks!

--D