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.
>
> --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) {
