mkfs: validate extent size hint parameters

Validate extent and cow extent size hints that are passed to mkfs so
that we avoid formatting a filesystem that will never mount.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
[sandeen: use DIFLAG macros for now to be consistent, fixed later]
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>

diff --git a/mkfs/xfs_mkfs.c b/mkfs/xfs_mkfs.c
index d1387ddf0539173606ed60d03a6a0354a8e2b09c..3343aaf1e93d020e2e3d93359819c9128064f372 100644 (file)
--- a/mkfs/xfs_mkfs.c
+++ b/mkfs/xfs_mkfs.c
@@ -2202,6 +2202,85 @@ validate_rtextsize(
        ASSERT(cfg->rtextblocks);
 }
 
+/* Validate the incoming extsize hint. */
+static void
+validate_extsize_hint(
+       struct xfs_mount        *mp,
+       struct cli_params       *cli)
+{
+       xfs_failaddr_t          fa;
+       uint16_t                flags = 0;
+
+       /*
+        * First we validate the extent size inherit hint on a directory so
+        * that we know that we'll be propagating a correct hint and flag to
+        * new files on the data device.
+        */
+       if (cli->fsx.fsx_xflags & XFS_DIFLAG_EXTSZINHERIT)
+               flags |= XFS_DIFLAG_EXTSZINHERIT;
+
+       fa = libxfs_inode_validate_extsize(mp, cli->fsx.fsx_extsize, S_IFDIR,
+                       flags);
+       if (fa) {
+               fprintf(stderr,
+_("illegal extent size hint %lld, must be less than %u.\n"),
+                               (long long)cli->fsx.fsx_extsize,
+                               min(MAXEXTLEN, mp->m_sb.sb_agblocks / 2));
+               usage();
+       }
+
+       /*
+        * Now we do it again with a realtime file so that we know the hint and
+        * flag that get passed on to realtime files will be correct.
+        */
+       if (mp->m_sb.sb_rextsize == 0)
+               return;
+
+       flags = XFS_DIFLAG_REALTIME;
+       if (cli->fsx.fsx_xflags & XFS_DIFLAG_EXTSIZE)
+               flags |= XFS_DIFLAG_EXTSIZE;
+
+       fa = libxfs_inode_validate_extsize(mp, cli->fsx.fsx_extsize, S_IFREG,
+                       flags);
+
+       if (fa) {
+               fprintf(stderr,
+_("illegal extent size hint %lld, must be less than %u and a multiple of %u.\n"),
+                               (long long)cli->fsx.fsx_extsize,
+                               min(MAXEXTLEN, mp->m_sb.sb_agblocks / 2),
+                               mp->m_sb.sb_rextsize);
+               usage();
+       }
+}
+
+/* Validate the incoming CoW extsize hint. */
+static void
+validate_cowextsize_hint(
+       struct xfs_mount        *mp,
+       struct cli_params       *cli)
+{
+       xfs_failaddr_t          fa;
+       uint64_t                flags2 = 0;
+
+       /*
+        * Validate the copy on write extent size inherit hint on a directory
+        * so that we know that we'll be propagating a correct hint and flag to
+        * new files on the data device.
+        */
+       if (cli->fsx.fsx_xflags & FS_XFLAG_COWEXTSIZE)
+               flags2 |= XFS_DIFLAG2_COWEXTSIZE;
+
+       fa = libxfs_inode_validate_cowextsize(mp, cli->fsx.fsx_cowextsize,
+                       S_IFDIR, 0, flags2);
+       if (fa) {
+               fprintf(stderr,
+_("illegal CoW extent size hint %lld, must be less than %u.\n"),
+                               (long long)cli->fsx.fsx_cowextsize,
+                               min(MAXEXTLEN, mp->m_sb.sb_agblocks / 2));
+               usage();
+       }
+}
+
 /*
  * Validate the configured stripe geometry, or is none is specified, pull
  * the configuration from the underlying device.
@@ -3945,6 +4024,10 @@ main(
 
        finish_superblock_setup(&cfg, mp, sbp);
 
+       /* Validate the extent size hints now that @mp is fully set up. */
+       validate_extsize_hint(mp, &cli);
+       validate_cowextsize_hint(mp, &cli);
+
        /* Print the intended geometry of the fs. */
        if (!quiet || dry_run) {
                struct xfs_fsop_geom    geo;