On Thu, Jul 28, 2022 at 03:38:38AM +0000, liuyd.fnst@xxxxxxxxxxx wrote:
> Hi, Darrick.
>
>
> On 7/28/22 10:37, Darrick J. Wong wrote:
> > Does this patch fix NFS for you?
>
> It works for me. Thanks.
> BTW. It has conflict during "git am". Looks like your branch are ahead
> of master.
Yes, I base my development branch off of for-next nowadays. Thanks for
the report, I'll add a tested-by if that's ok and send it out as a bug
fix.
--D
> >
> > --D
> > ---
> > From: Darrick J. Wong <djwong@xxxxxxxxxx>
> >
> > seek_sanity_test: use XFS ioctls to determine file allocation unit size
> >
> > liuyd.fnst@xxxxxxxxxxx reported that my recent change to the seek sanity
> > test broke NFS. I foolishly thought that st_blksize was sufficient to
> > find the file allocation unit size so that applications could figure out
> > the SEEK_HOLE granularity. Replace that with an explicit callout to XFS
> > ioctls so that xfs realtime will work again.
> >
> > Fixes: e861a302 ("seek_sanity_test: fix allocation unit detection on XFS realtime")
> > Reported-by: liuyd.fnst@xxxxxxxxxxx
> > Signed-off-by: Darrick J. Wong <djwong@xxxxxxxxxx>
> > ---
> > src/Makefile | 4 ++++
> > src/seek_sanity_test.c | 40 +++++++++++++++++++++++++++++++---------
> > 2 files changed, 35 insertions(+), 9 deletions(-)
> >
> > diff --git a/src/Makefile b/src/Makefile
> > index 38628a22..b89a7a5e 100644
> > --- a/src/Makefile
> > +++ b/src/Makefile
> > @@ -82,6 +82,10 @@ ifeq ($(HAVE_LIBCAP), true)
> > LLDLIBS += -lcap
> > endif
> >
> > +ifeq ($(HAVE_FSXATTR_XFLAG_HASATTR), yes)
> > +LCFLAGS += -DHAVE_FSXATTR_XFLAG_HASATTR
> > +endif
> > +
> > ifeq ($(HAVE_SEEK_DATA), yes)
> > ifeq ($(HAVE_FSXATTR_XFLAG_HASATTR), yes)
> > ifeq ($(HAVE_NFTW), yes)
> > diff --git a/src/seek_sanity_test.c b/src/seek_sanity_test.c
> > index 1030d0c5..b53f4862 100644
> > --- a/src/seek_sanity_test.c
> > +++ b/src/seek_sanity_test.c
> > @@ -40,6 +40,32 @@ static void get_file_system(int fd)
> > }
> > }
> >
> > +#ifdef HAVE_FSXATTR_XFLAG_HASATTR
> > +/* Compute the file allocation unit size for an XFS file. */
> > +static int detect_xfs_alloc_unit(int fd)
> > +{
> > + struct fsxattr fsx;
> > + struct xfs_fsop_geom fsgeom;
> > + int ret;
> > +
> > + ret = ioctl(fd, XFS_IOC_FSGEOMETRY, &fsgeom);
> > + if (ret)
> > + return -1;
> > +
> > + ret = ioctl(fd, FS_IOC_FSGETXATTR, &fsx);
> > + if (ret)
> > + return -1;
> > +
> > + alloc_size = fsgeom.blocksize;
> > + if (fsx.fsx_xflags & FS_XFLAG_REALTIME)
> > + alloc_size *= fsgeom.rtextsize;
> > +
> > + return 0;
> > +}
> > +#else
> > +# define detect_xfs_alloc_unit(fd) (-1)
> > +#endif
> > +
> > static int get_io_sizes(int fd)
> > {
> > off_t pos = 0, offset = 1;
> > @@ -47,6 +73,10 @@ static int get_io_sizes(int fd)
> > int shift, ret;
> > int pagesz = sysconf(_SC_PAGE_SIZE);
> >
> > + ret = detect_xfs_alloc_unit(fd);
> > + if (!ret)
> > + goto done;
> > +
> > ret = fstat(fd, &buf);
> > if (ret) {
> > fprintf(stderr, " ERROR %d: Failed to find io blocksize\n",
> > @@ -54,16 +84,8 @@ static int get_io_sizes(int fd)
> > return ret;
> > }
> >
> > - /*
> > - * st_blksize is typically also the allocation size. However, XFS
> > - * rounds this up to the page size, so if the stat blocksize is exactly
> > - * one page, use this iterative algorithm to see if SEEK_DATA will hint
> > - * at a more precise answer based on the filesystem's (pre)allocation
> > - * decisions.
> > - */
> > + /* st_blksize is typically also the allocation size */
> > alloc_size = buf.st_blksize;
> > - if (alloc_size != pagesz)
> > - goto done;
> >
> > /* try to discover the actual alloc size */
> > while (pos == 0 && offset < alloc_size) {
