[PATCH v2 0/2] get UUID of mounted filesystems

[PATCH v2 0/2] get UUID of mounted filesystems

[Catherine Hoang]

Hi all,

This series adds a new fsuuid command and adapts xfs_admin to call xfs_io
when a filesystem is mounted. This is a precursor to enabling xfs_admin to
set the UUID of a mounted filesystem.

v1->v2:
- Add fsuuid command to xfs_io man page
- xfs_admin returns error if both online and offline options are specified
- Update xfs_admin man page

Comments and feedback appreciated!

Catherine

Catherine Hoang (2):
  xfs_io: add fsuuid command
  xfs_admin: get UUID of mounted filesystem

 db/xfs_admin.sh      | 27 ++++++++++++++++++++----
 io/Makefile          |  6 +++---
 io/fsuuid.c          | 49 ++++++++++++++++++++++++++++++++++++++++++++
 io/init.c            |  1 +
 io/io.h              |  1 +
 man/man8/xfs_admin.8 |  4 ++++
 man/man8/xfs_io.8    |  3 +++
 7 files changed, 84 insertions(+), 7 deletions(-)
 create mode 100644 io/fsuuid.c

-- 
2.25.1

[PATCH v2 1/2] xfs_io: add fsuuid command

[Catherine Hoang]

Add support for the fsuuid command to retrieve the UUID of a mounted
filesystem.

Signed-off-by: Catherine Hoang <catherine.hoang@oracle.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
---
 io/Makefile       |  6 +++---
 io/fsuuid.c       | 49 +++++++++++++++++++++++++++++++++++++++++++++++
 io/init.c         |  1 +
 io/io.h           |  1 +
 man/man8/xfs_io.8 |  3 +++
 5 files changed, 57 insertions(+), 3 deletions(-)
 create mode 100644 io/fsuuid.c

diff --git a/io/Makefile b/io/Makefile
index 498174cf..53fef09e 100644
--- a/io/Makefile
+++ b/io/Makefile
@@ -10,12 +10,12 @@ LSRCFILES = xfs_bmap.sh xfs_freeze.sh xfs_mkfile.sh
 HFILES = init.h io.h
 CFILES = init.c \
 	attr.c bmap.c bulkstat.c crc32cselftest.c cowextsize.c encrypt.c \
-	file.c freeze.c fsync.c getrusage.c imap.c inject.c label.c link.c \
-	mmap.c open.c parent.c pread.c prealloc.c pwrite.c reflink.c \
+	file.c freeze.c fsuuid.c fsync.c getrusage.c imap.c inject.c label.c \
+	link.c mmap.c open.c parent.c pread.c prealloc.c pwrite.c reflink.c \
 	resblks.c scrub.c seek.c shutdown.c stat.c swapext.c sync.c \
 	truncate.c utimes.c
 
-LLDLIBS = $(LIBXCMD) $(LIBHANDLE) $(LIBFROG) $(LIBPTHREAD)
+LLDLIBS = $(LIBXCMD) $(LIBHANDLE) $(LIBFROG) $(LIBPTHREAD) $(LIBUUID)
 LTDEPENDENCIES = $(LIBXCMD) $(LIBHANDLE) $(LIBFROG)
 LLDFLAGS = -static-libtool-libs
 
diff --git a/io/fsuuid.c b/io/fsuuid.c
new file mode 100644
index 00000000..7e14a95d
--- /dev/null
+++ b/io/fsuuid.c
@@ -0,0 +1,49 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2022 Oracle.
+ * All Rights Reserved.
+ */
+
+#include "libxfs.h"
+#include "command.h"
+#include "init.h"
+#include "io.h"
+#include "libfrog/fsgeom.h"
+#include "libfrog/logging.h"
+
+static cmdinfo_t fsuuid_cmd;
+
+static int
+fsuuid_f(
+	int			argc,
+	char			**argv)
+{
+	struct xfs_fsop_geom	fsgeo;
+	int			ret;
+	char			bp[40];
+
+	ret = -xfrog_geometry(file->fd, &fsgeo);
+
+	if (ret) {
+		xfrog_perror(ret, "XFS_IOC_FSGEOMETRY");
+		exitcode = 1;
+	} else {
+		platform_uuid_unparse((uuid_t *)fsgeo.uuid, bp);
+		printf("UUID = %s\n", bp);
+	}
+
+	return 0;
+}
+
+void
+fsuuid_init(void)
+{
+	fsuuid_cmd.name = "fsuuid";
+	fsuuid_cmd.cfunc = fsuuid_f;
+	fsuuid_cmd.argmin = 0;
+	fsuuid_cmd.argmax = 0;
+	fsuuid_cmd.flags = CMD_FLAG_ONESHOT | CMD_NOMAP_OK;
+	fsuuid_cmd.oneline = _("get mounted filesystem UUID");
+
+	add_command(&fsuuid_cmd);
+}
diff --git a/io/init.c b/io/init.c
index 033ed67d..104cd2c1 100644
--- a/io/init.c
+++ b/io/init.c
@@ -56,6 +56,7 @@ init_commands(void)
 	flink_init();
 	freeze_init();
 	fsmap_init();
+	fsuuid_init();
 	fsync_init();
 	getrusage_init();
 	help_init();
diff --git a/io/io.h b/io/io.h
index 64b7a663..fe474faf 100644
--- a/io/io.h
+++ b/io/io.h
@@ -94,6 +94,7 @@ extern void		encrypt_init(void);
 extern void		file_init(void);
 extern void		flink_init(void);
 extern void		freeze_init(void);
+extern void		fsuuid_init(void);
 extern void		fsync_init(void);
 extern void		getrusage_init(void);
 extern void		help_init(void);
diff --git a/man/man8/xfs_io.8 b/man/man8/xfs_io.8
index 223b5152..ef7087b3 100644
--- a/man/man8/xfs_io.8
+++ b/man/man8/xfs_io.8
@@ -1455,6 +1455,9 @@ This option is not compatible with the
 flag.
 .RE
 .PD
+.TP
+.B fsuuid
+Print the mounted filesystem UUID.
 
 
 .SH OTHER COMMANDS
-- 
2.25.1

Re: [PATCH v2 1/2] xfs_io: add fsuuid command

[Darrick J. Wong]

On Mon, Dec 19, 2022 at 10:18:23AM -0800, Catherine Hoang wrote:
> Add support for the fsuuid command to retrieve the UUID of a mounted
> filesystem.
> 
> Signed-off-by: Catherine Hoang <catherine.hoang@oracle.com>
> Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
> ---
>  io/Makefile       |  6 +++---
>  io/fsuuid.c       | 49 +++++++++++++++++++++++++++++++++++++++++++++++
>  io/init.c         |  1 +
>  io/io.h           |  1 +
>  man/man8/xfs_io.8 |  3 +++
>  5 files changed, 57 insertions(+), 3 deletions(-)
>  create mode 100644 io/fsuuid.c
> 
> diff --git a/io/Makefile b/io/Makefile
> index 498174cf..53fef09e 100644
> --- a/io/Makefile
> +++ b/io/Makefile
> @@ -10,12 +10,12 @@ LSRCFILES = xfs_bmap.sh xfs_freeze.sh xfs_mkfile.sh
>  HFILES = init.h io.h
>  CFILES = init.c \
>  	attr.c bmap.c bulkstat.c crc32cselftest.c cowextsize.c encrypt.c \
> -	file.c freeze.c fsync.c getrusage.c imap.c inject.c label.c link.c \
> -	mmap.c open.c parent.c pread.c prealloc.c pwrite.c reflink.c \
> +	file.c freeze.c fsuuid.c fsync.c getrusage.c imap.c inject.c label.c \
> +	link.c mmap.c open.c parent.c pread.c prealloc.c pwrite.c reflink.c \
>  	resblks.c scrub.c seek.c shutdown.c stat.c swapext.c sync.c \
>  	truncate.c utimes.c
>  
> -LLDLIBS = $(LIBXCMD) $(LIBHANDLE) $(LIBFROG) $(LIBPTHREAD)
> +LLDLIBS = $(LIBXCMD) $(LIBHANDLE) $(LIBFROG) $(LIBPTHREAD) $(LIBUUID)
>  LTDEPENDENCIES = $(LIBXCMD) $(LIBHANDLE) $(LIBFROG)
>  LLDFLAGS = -static-libtool-libs
>  
> diff --git a/io/fsuuid.c b/io/fsuuid.c
> new file mode 100644
> index 00000000..7e14a95d
> --- /dev/null
> +++ b/io/fsuuid.c
> @@ -0,0 +1,49 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (c) 2022 Oracle.
> + * All Rights Reserved.
> + */
> +
> +#include "libxfs.h"
> +#include "command.h"
> +#include "init.h"
> +#include "io.h"
> +#include "libfrog/fsgeom.h"
> +#include "libfrog/logging.h"
> +
> +static cmdinfo_t fsuuid_cmd;
> +
> +static int
> +fsuuid_f(
> +	int			argc,
> +	char			**argv)
> +{
> +	struct xfs_fsop_geom	fsgeo;
> +	int			ret;
> +	char			bp[40];
> +
> +	ret = -xfrog_geometry(file->fd, &fsgeo);
> +
> +	if (ret) {
> +		xfrog_perror(ret, "XFS_IOC_FSGEOMETRY");
> +		exitcode = 1;
> +	} else {
> +		platform_uuid_unparse((uuid_t *)fsgeo.uuid, bp);
> +		printf("UUID = %s\n", bp);

Lowercase "uuid" to match the xfs_db uuid command.

With that fixed,
Reviewed-by: Darrick J. Wong <djwong@kernel.org>

--D

> +	}
> +
> +	return 0;
> +}
> +
> +void
> +fsuuid_init(void)
> +{
> +	fsuuid_cmd.name = "fsuuid";
> +	fsuuid_cmd.cfunc = fsuuid_f;
> +	fsuuid_cmd.argmin = 0;
> +	fsuuid_cmd.argmax = 0;
> +	fsuuid_cmd.flags = CMD_FLAG_ONESHOT | CMD_NOMAP_OK;
> +	fsuuid_cmd.oneline = _("get mounted filesystem UUID");
> +
> +	add_command(&fsuuid_cmd);
> +}
> diff --git a/io/init.c b/io/init.c
> index 033ed67d..104cd2c1 100644
> --- a/io/init.c
> +++ b/io/init.c
> @@ -56,6 +56,7 @@ init_commands(void)
>  	flink_init();
>  	freeze_init();
>  	fsmap_init();
> +	fsuuid_init();
>  	fsync_init();
>  	getrusage_init();
>  	help_init();
> diff --git a/io/io.h b/io/io.h
> index 64b7a663..fe474faf 100644
> --- a/io/io.h
> +++ b/io/io.h
> @@ -94,6 +94,7 @@ extern void		encrypt_init(void);
>  extern void		file_init(void);
>  extern void		flink_init(void);
>  extern void		freeze_init(void);
> +extern void		fsuuid_init(void);
>  extern void		fsync_init(void);
>  extern void		getrusage_init(void);
>  extern void		help_init(void);
> diff --git a/man/man8/xfs_io.8 b/man/man8/xfs_io.8
> index 223b5152..ef7087b3 100644
> --- a/man/man8/xfs_io.8
> +++ b/man/man8/xfs_io.8
> @@ -1455,6 +1455,9 @@ This option is not compatible with the
>  flag.
>  .RE
>  .PD
> +.TP
> +.B fsuuid
> +Print the mounted filesystem UUID.
>  
>  
>  .SH OTHER COMMANDS
> -- 
> 2.25.1
> 

Re: [PATCH v2 1/2] xfs_io: add fsuuid command

[Catherine Hoang]

> On Dec 20, 2022, at 1:55 PM, Darrick J. Wong <djwong@kernel.org> wrote:
> 
> On Mon, Dec 19, 2022 at 10:18:23AM -0800, Catherine Hoang wrote:
>> Add support for the fsuuid command to retrieve the UUID of a mounted
>> filesystem.
>> 
>> Signed-off-by: Catherine Hoang <catherine.hoang@oracle.com>
>> Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
>> ---
>> io/Makefile       |  6 +++---
>> io/fsuuid.c       | 49 +++++++++++++++++++++++++++++++++++++++++++++++
>> io/init.c         |  1 +
>> io/io.h           |  1 +
>> man/man8/xfs_io.8 |  3 +++
>> 5 files changed, 57 insertions(+), 3 deletions(-)
>> create mode 100644 io/fsuuid.c
>> 
>> diff --git a/io/Makefile b/io/Makefile
>> index 498174cf..53fef09e 100644
>> --- a/io/Makefile
>> +++ b/io/Makefile
>> @@ -10,12 +10,12 @@ LSRCFILES = xfs_bmap.sh xfs_freeze.sh xfs_mkfile.sh
>> HFILES = init.h io.h
>> CFILES = init.c \
>> 	attr.c bmap.c bulkstat.c crc32cselftest.c cowextsize.c encrypt.c \
>> -	file.c freeze.c fsync.c getrusage.c imap.c inject.c label.c link.c \
>> -	mmap.c open.c parent.c pread.c prealloc.c pwrite.c reflink.c \
>> +	file.c freeze.c fsuuid.c fsync.c getrusage.c imap.c inject.c label.c \
>> +	link.c mmap.c open.c parent.c pread.c prealloc.c pwrite.c reflink.c \
>> 	resblks.c scrub.c seek.c shutdown.c stat.c swapext.c sync.c \
>> 	truncate.c utimes.c
>> 
>> -LLDLIBS = $(LIBXCMD) $(LIBHANDLE) $(LIBFROG) $(LIBPTHREAD)
>> +LLDLIBS = $(LIBXCMD) $(LIBHANDLE) $(LIBFROG) $(LIBPTHREAD) $(LIBUUID)
>> LTDEPENDENCIES = $(LIBXCMD) $(LIBHANDLE) $(LIBFROG)
>> LLDFLAGS = -static-libtool-libs
>> 
>> diff --git a/io/fsuuid.c b/io/fsuuid.c
>> new file mode 100644
>> index 00000000..7e14a95d
>> --- /dev/null
>> +++ b/io/fsuuid.c
>> @@ -0,0 +1,49 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/*
>> + * Copyright (c) 2022 Oracle.
>> + * All Rights Reserved.
>> + */
>> +
>> +#include "libxfs.h"
>> +#include "command.h"
>> +#include "init.h"
>> +#include "io.h"
>> +#include "libfrog/fsgeom.h"
>> +#include "libfrog/logging.h"
>> +
>> +static cmdinfo_t fsuuid_cmd;
>> +
>> +static int
>> +fsuuid_f(
>> +	int			argc,
>> +	char			**argv)
>> +{
>> +	struct xfs_fsop_geom	fsgeo;
>> +	int			ret;
>> +	char			bp[40];
>> +
>> +	ret = -xfrog_geometry(file->fd, &fsgeo);
>> +
>> +	if (ret) {
>> +		xfrog_perror(ret, "XFS_IOC_FSGEOMETRY");
>> +		exitcode = 1;
>> +	} else {
>> +		platform_uuid_unparse((uuid_t *)fsgeo.uuid, bp);
>> +		printf("UUID = %s\n", bp);
> 
> Lowercase "uuid" to match the xfs_db uuid command.

I noticed xfs_db also prints “uuid" in uppercase, so I didn’t change it
> 
> With that fixed,
> Reviewed-by: Darrick J. Wong <djwong@kernel.org>

Thanks for reviewing!
> 
> --D
> 
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +void
>> +fsuuid_init(void)
>> +{
>> +	fsuuid_cmd.name = "fsuuid";
>> +	fsuuid_cmd.cfunc = fsuuid_f;
>> +	fsuuid_cmd.argmin = 0;
>> +	fsuuid_cmd.argmax = 0;
>> +	fsuuid_cmd.flags = CMD_FLAG_ONESHOT | CMD_NOMAP_OK;
>> +	fsuuid_cmd.oneline = _("get mounted filesystem UUID");
>> +
>> +	add_command(&fsuuid_cmd);
>> +}
>> diff --git a/io/init.c b/io/init.c
>> index 033ed67d..104cd2c1 100644
>> --- a/io/init.c
>> +++ b/io/init.c
>> @@ -56,6 +56,7 @@ init_commands(void)
>> 	flink_init();
>> 	freeze_init();
>> 	fsmap_init();
>> +	fsuuid_init();
>> 	fsync_init();
>> 	getrusage_init();
>> 	help_init();
>> diff --git a/io/io.h b/io/io.h
>> index 64b7a663..fe474faf 100644
>> --- a/io/io.h
>> +++ b/io/io.h
>> @@ -94,6 +94,7 @@ extern void		encrypt_init(void);
>> extern void		file_init(void);
>> extern void		flink_init(void);
>> extern void		freeze_init(void);
>> +extern void		fsuuid_init(void);
>> extern void		fsync_init(void);
>> extern void		getrusage_init(void);
>> extern void		help_init(void);
>> diff --git a/man/man8/xfs_io.8 b/man/man8/xfs_io.8
>> index 223b5152..ef7087b3 100644
>> --- a/man/man8/xfs_io.8
>> +++ b/man/man8/xfs_io.8
>> @@ -1455,6 +1455,9 @@ This option is not compatible with the
>> flag.
>> .RE
>> .PD
>> +.TP
>> +.B fsuuid
>> +Print the mounted filesystem UUID.
>> 
>> 
>> .SH OTHER COMMANDS
>> -- 
>> 2.25.1
>> 

Re: [PATCH v2 1/2] xfs_io: add fsuuid command

[Darrick J. Wong]

On Wed, Dec 21, 2022 at 07:11:42AM +0000, Catherine Hoang wrote:
> > On Dec 20, 2022, at 1:55 PM, Darrick J. Wong <djwong@kernel.org> wrote:
> > 
> > On Mon, Dec 19, 2022 at 10:18:23AM -0800, Catherine Hoang wrote:
> >> Add support for the fsuuid command to retrieve the UUID of a mounted
> >> filesystem.
> >> 
> >> Signed-off-by: Catherine Hoang <catherine.hoang@oracle.com>
> >> Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
> >> ---
> >> io/Makefile       |  6 +++---
> >> io/fsuuid.c       | 49 +++++++++++++++++++++++++++++++++++++++++++++++
> >> io/init.c         |  1 +
> >> io/io.h           |  1 +
> >> man/man8/xfs_io.8 |  3 +++
> >> 5 files changed, 57 insertions(+), 3 deletions(-)
> >> create mode 100644 io/fsuuid.c
> >> 
> >> diff --git a/io/Makefile b/io/Makefile
> >> index 498174cf..53fef09e 100644
> >> --- a/io/Makefile
> >> +++ b/io/Makefile
> >> @@ -10,12 +10,12 @@ LSRCFILES = xfs_bmap.sh xfs_freeze.sh xfs_mkfile.sh
> >> HFILES = init.h io.h
> >> CFILES = init.c \
> >> 	attr.c bmap.c bulkstat.c crc32cselftest.c cowextsize.c encrypt.c \
> >> -	file.c freeze.c fsync.c getrusage.c imap.c inject.c label.c link.c \
> >> -	mmap.c open.c parent.c pread.c prealloc.c pwrite.c reflink.c \
> >> +	file.c freeze.c fsuuid.c fsync.c getrusage.c imap.c inject.c label.c \
> >> +	link.c mmap.c open.c parent.c pread.c prealloc.c pwrite.c reflink.c \
> >> 	resblks.c scrub.c seek.c shutdown.c stat.c swapext.c sync.c \
> >> 	truncate.c utimes.c
> >> 
> >> -LLDLIBS = $(LIBXCMD) $(LIBHANDLE) $(LIBFROG) $(LIBPTHREAD)
> >> +LLDLIBS = $(LIBXCMD) $(LIBHANDLE) $(LIBFROG) $(LIBPTHREAD) $(LIBUUID)
> >> LTDEPENDENCIES = $(LIBXCMD) $(LIBHANDLE) $(LIBFROG)
> >> LLDFLAGS = -static-libtool-libs
> >> 
> >> diff --git a/io/fsuuid.c b/io/fsuuid.c
> >> new file mode 100644
> >> index 00000000..7e14a95d
> >> --- /dev/null
> >> +++ b/io/fsuuid.c
> >> @@ -0,0 +1,49 @@
> >> +// SPDX-License-Identifier: GPL-2.0
> >> +/*
> >> + * Copyright (c) 2022 Oracle.
> >> + * All Rights Reserved.
> >> + */
> >> +
> >> +#include "libxfs.h"
> >> +#include "command.h"
> >> +#include "init.h"
> >> +#include "io.h"
> >> +#include "libfrog/fsgeom.h"
> >> +#include "libfrog/logging.h"
> >> +
> >> +static cmdinfo_t fsuuid_cmd;
> >> +
> >> +static int
> >> +fsuuid_f(
> >> +	int			argc,
> >> +	char			**argv)
> >> +{
> >> +	struct xfs_fsop_geom	fsgeo;
> >> +	int			ret;
> >> +	char			bp[40];
> >> +
> >> +	ret = -xfrog_geometry(file->fd, &fsgeo);
> >> +
> >> +	if (ret) {
> >> +		xfrog_perror(ret, "XFS_IOC_FSGEOMETRY");
> >> +		exitcode = 1;
> >> +	} else {
> >> +		platform_uuid_unparse((uuid_t *)fsgeo.uuid, bp);
> >> +		printf("UUID = %s\n", bp);
> > 
> > Lowercase "uuid" to match the xfs_db uuid command.
> 
> I noticed xfs_db also prints “uuid" in uppercase, so I didn’t change it

Lol, dunno why I didn't notice that. :/

Carry on!

--D

> > With that fixed,
> > Reviewed-by: Darrick J. Wong <djwong@kernel.org>
> 
> Thanks for reviewing!
> > 
> > --D
> > 
> >> +	}
> >> +
> >> +	return 0;
> >> +}
> >> +
> >> +void
> >> +fsuuid_init(void)
> >> +{
> >> +	fsuuid_cmd.name = "fsuuid";
> >> +	fsuuid_cmd.cfunc = fsuuid_f;
> >> +	fsuuid_cmd.argmin = 0;
> >> +	fsuuid_cmd.argmax = 0;
> >> +	fsuuid_cmd.flags = CMD_FLAG_ONESHOT | CMD_NOMAP_OK;
> >> +	fsuuid_cmd.oneline = _("get mounted filesystem UUID");
> >> +
> >> +	add_command(&fsuuid_cmd);
> >> +}
> >> diff --git a/io/init.c b/io/init.c
> >> index 033ed67d..104cd2c1 100644
> >> --- a/io/init.c
> >> +++ b/io/init.c
> >> @@ -56,6 +56,7 @@ init_commands(void)
> >> 	flink_init();
> >> 	freeze_init();
> >> 	fsmap_init();
> >> +	fsuuid_init();
> >> 	fsync_init();
> >> 	getrusage_init();
> >> 	help_init();
> >> diff --git a/io/io.h b/io/io.h
> >> index 64b7a663..fe474faf 100644
> >> --- a/io/io.h
> >> +++ b/io/io.h
> >> @@ -94,6 +94,7 @@ extern void		encrypt_init(void);
> >> extern void		file_init(void);
> >> extern void		flink_init(void);
> >> extern void		freeze_init(void);
> >> +extern void		fsuuid_init(void);
> >> extern void		fsync_init(void);
> >> extern void		getrusage_init(void);
> >> extern void		help_init(void);
> >> diff --git a/man/man8/xfs_io.8 b/man/man8/xfs_io.8
> >> index 223b5152..ef7087b3 100644
> >> --- a/man/man8/xfs_io.8
> >> +++ b/man/man8/xfs_io.8
> >> @@ -1455,6 +1455,9 @@ This option is not compatible with the
> >> flag.
> >> .RE
> >> .PD
> >> +.TP
> >> +.B fsuuid
> >> +Print the mounted filesystem UUID.
> >> 
> >> 
> >> .SH OTHER COMMANDS
> >> -- 
> >> 2.25.1
> >> 
> 

[PATCH v2 2/2] xfs_admin: get UUID of mounted filesystem

[Catherine Hoang]

Adapt this tool to call xfs_io to retrieve the UUID of a mounted filesystem.
This is a precursor to enabling xfs_admin to set the UUID of a mounted
filesystem.

Signed-off-by: Catherine Hoang <catherine.hoang@oracle.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
---
 db/xfs_admin.sh      | 27 +++++++++++++++++++++++----
 man/man8/xfs_admin.8 |  4 ++++
 2 files changed, 27 insertions(+), 4 deletions(-)

diff --git a/db/xfs_admin.sh b/db/xfs_admin.sh
index 409975b2..cc9a2150 100755
--- a/db/xfs_admin.sh
+++ b/db/xfs_admin.sh
@@ -6,10 +6,12 @@
 
 status=0
 DB_OPTS=""
+DB_EXTRA_OPTS=""
+IO_OPTS=""
 REPAIR_OPTS=""
 REPAIR_DEV_OPTS=""
 LOG_OPTS=""
-USAGE="Usage: xfs_admin [-efjlpuV] [-c 0|1] [-L label] [-O v5_feature] [-r rtdev] [-U uuid] device [logdev]"
+USAGE="Usage: xfs_admin [-efjlpuV] [-c 0|1] [-L label] [-O v5_feature] [-r rtdev] [-U uuid] [mountpoint|device] [logdev]"
 
 while getopts "c:efjlL:O:pr:uU:V" c
 do
@@ -23,7 +25,8 @@ do
 	O)	REPAIR_OPTS=$REPAIR_OPTS" -c $OPTARG";;
 	p)	DB_OPTS=$DB_OPTS" -c 'version projid32bit'";;
 	r)	REPAIR_DEV_OPTS=" -r '$OPTARG'";;
-	u)	DB_OPTS=$DB_OPTS" -r -c uuid";;
+	u)	DB_EXTRA_OPTS=$DB_EXTRA_OPTS" -r -c uuid";
+		IO_OPTS=$IO_OPTS" -r -c fsuuid";;
 	U)	DB_OPTS=$DB_OPTS" -c 'uuid "$OPTARG"'";;
 	V)	xfs_db -p xfs_admin -V
 		status=$?
@@ -38,14 +41,30 @@ set -- extra $@
 shift $OPTIND
 case $# in
 	1|2)
+		# Target either a device or mountpoint, not both
+		if [ -n "$(findmnt -t xfs -T $1)" ]; then
+			if [ -n "$DB_OPTS" ] || [ -n "$REPAIR_OPTS" ]; then
+				echo "Offline options target a device, not mountpoint."
+				exit 2
+			fi
+			DB_EXTRA_OPTS=""
+		else
+			IO_OPTS=""
+		fi
+
 		# Pick up the log device, if present
 		if [ -n "$2" ]; then
 			LOG_OPTS=" -l '$2'"
 		fi
 
-		if [ -n "$DB_OPTS" ]
+		if [ -n "$DB_OPTS" ] || [ -n "$DB_EXTRA_OPTS" ]
+		then
+			eval xfs_db -x -p xfs_admin $LOG_OPTS $DB_OPTS $DB_EXTRA_OPTS "$1"
+			status=$?
+		fi
+		if [ -n "$IO_OPTS" ]
 		then
-			eval xfs_db -x -p xfs_admin $LOG_OPTS $DB_OPTS "$1"
+			eval xfs_io -x -p xfs_admin $IO_OPTS "$1"
 			status=$?
 		fi
 		if [ -n "$REPAIR_OPTS" ]
diff --git a/man/man8/xfs_admin.8 b/man/man8/xfs_admin.8
index 4794d677..2c7ddc15 100644
--- a/man/man8/xfs_admin.8
+++ b/man/man8/xfs_admin.8
@@ -19,7 +19,11 @@ xfs_admin \- change parameters of an XFS filesystem
 .B \-r
 .I rtdev
 ]
+[
+.I mount-point
+|
 .I device
+]
 [
 .I logdev
 ]
-- 
2.25.1

Re: [PATCH v2 2/2] xfs_admin: get UUID of mounted filesystem

[Darrick J. Wong]

On Mon, Dec 19, 2022 at 10:18:24AM -0800, Catherine Hoang wrote:
> Adapt this tool to call xfs_io to retrieve the UUID of a mounted filesystem.
> This is a precursor to enabling xfs_admin to set the UUID of a mounted
> filesystem.
> 
> Signed-off-by: Catherine Hoang <catherine.hoang@oracle.com>
> Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
> ---
>  db/xfs_admin.sh      | 27 +++++++++++++++++++++++----
>  man/man8/xfs_admin.8 |  4 ++++
>  2 files changed, 27 insertions(+), 4 deletions(-)
> 
> diff --git a/db/xfs_admin.sh b/db/xfs_admin.sh
> index 409975b2..cc9a2150 100755
> --- a/db/xfs_admin.sh
> +++ b/db/xfs_admin.sh
> @@ -6,10 +6,12 @@
>  
>  status=0
>  DB_OPTS=""
> +DB_EXTRA_OPTS=""
> +IO_OPTS=""
>  REPAIR_OPTS=""
>  REPAIR_DEV_OPTS=""
>  LOG_OPTS=""
> -USAGE="Usage: xfs_admin [-efjlpuV] [-c 0|1] [-L label] [-O v5_feature] [-r rtdev] [-U uuid] device [logdev]"
> +USAGE="Usage: xfs_admin [-efjlpuV] [-c 0|1] [-L label] [-O v5_feature] [-r rtdev] [-U uuid] [mountpoint|device] [logdev]"

I don't think it's necessary to expand xfs_admin to take a mount point,
since findmnt returns the mount point associated with a block device.

>  
>  while getopts "c:efjlL:O:pr:uU:V" c
>  do
> @@ -23,7 +25,8 @@ do
>  	O)	REPAIR_OPTS=$REPAIR_OPTS" -c $OPTARG";;
>  	p)	DB_OPTS=$DB_OPTS" -c 'version projid32bit'";;
>  	r)	REPAIR_DEV_OPTS=" -r '$OPTARG'";;
> -	u)	DB_OPTS=$DB_OPTS" -r -c uuid";;
> +	u)	DB_EXTRA_OPTS=$DB_EXTRA_OPTS" -r -c uuid";
> +		IO_OPTS=$IO_OPTS" -r -c fsuuid";;
>  	U)	DB_OPTS=$DB_OPTS" -c 'uuid "$OPTARG"'";;
>  	V)	xfs_db -p xfs_admin -V
>  		status=$?
> @@ -38,14 +41,30 @@ set -- extra $@
>  shift $OPTIND
>  case $# in
>  	1|2)
> +		# Target either a device or mountpoint, not both
> +		if [ -n "$(findmnt -t xfs -T $1)" ]; then

Note that xfs_io acts upon a mountpoint, not a block device, so you
need to save the mount point that findmnt returns here.  You might also
want to look at the -o option to constrain its output to only the
information you need.

> +			if [ -n "$DB_OPTS" ] || [ -n "$REPAIR_OPTS" ]; then
> +				echo "Offline options target a device, not mountpoint."
> +				exit 2
> +			fi
> +			DB_EXTRA_OPTS=""
> +		else
> +			IO_OPTS=""

Hmm.  DB_EXTRA_OPS is really the container of xfs_db commands that also
have xfs_io alternatives, whereas DB_OPTS/REPAIR_OPTS are things that
require an unmounted fs.  Yet we can't access OPTIND until after we've
completely finished getopts processing.  I suspect this isn't a great
way to be handling this, because what does "EXTRA" mean, actually?  It's
not immediately obvious from the name.

I can't help but wonder if the behaviors would be clearer if we tracked
explicitly which subcommands require a mounted fs, which ones require an
unmounted fs (nearly all of them), and which ones can go back and forth.
Something like this:

require_offline=""
require_online=""
DB_OPTS=""
REPAIR_OPTS=""
IO_OPTS=""
<more initialization>

while getopts "c:efjlL:O:pr:uU:V" c
do
	case $c in
	c)
		REPAIR_OPTS=$REPAIR_OPTS" -c lazycount="$OPTARG
		require_offline=1
		;;

	<more options here>

	u)
		DB_OPTS=$DB_OPTS" -r -c uuid"
		IO_OPTS=$IO_OPTS" -c uuid"
		;;
	U)
		DB_OPTS=$DB_OPTS" -c 'uuid "$OPTARG"'"
		require_offline=1
		;;

	<rest of options here>
done

...and then later on when it's time to take action...

		if mntpt="$(findmnt -t xfs -f -n -o TARGET "$1" 2>/dev/null)"; then
			# filesystem is mounted
			if [ -n "$require_offline" ]; then
				echo "$1: filesystem is mounted."
				exit 2
			fi

			exec xfs_io -p xfs_admin "$IO_OPTS" "$mntpt"
		fi

		# filesystem is not mounted
		if [ -n "$require_offline" ]; then
			echo "$1: filesystem is not mounted"
			exit 2
		fi

		<regular DB_OPTS/REPAIR_OPTS processing>

--D

> +		fi
> +
>  		# Pick up the log device, if present
>  		if [ -n "$2" ]; then
>  			LOG_OPTS=" -l '$2'"
>  		fi
>  
> -		if [ -n "$DB_OPTS" ]
> +		if [ -n "$DB_OPTS" ] || [ -n "$DB_EXTRA_OPTS" ]
> +		then
> +			eval xfs_db -x -p xfs_admin $LOG_OPTS $DB_OPTS $DB_EXTRA_OPTS "$1"
> +			status=$?
> +		fi
> +		if [ -n "$IO_OPTS" ]
>  		then
> -			eval xfs_db -x -p xfs_admin $LOG_OPTS $DB_OPTS "$1"
> +			eval xfs_io -x -p xfs_admin $IO_OPTS "$1"
>  			status=$?
>  		fi
>  		if [ -n "$REPAIR_OPTS" ]
> diff --git a/man/man8/xfs_admin.8 b/man/man8/xfs_admin.8
> index 4794d677..2c7ddc15 100644
> --- a/man/man8/xfs_admin.8
> +++ b/man/man8/xfs_admin.8
> @@ -19,7 +19,11 @@ xfs_admin \- change parameters of an XFS filesystem
>  .B \-r
>  .I rtdev
>  ]
> +[
> +.I mount-point
> +|
>  .I device
> +]
>  [
>  .I logdev
>  ]
> -- 
> 2.25.1
>