[PATCH] fallocate() for FFS

[manu%netbsd.org@localhost (Emmanuel Dreyfus)]

Implementing fallocate for FFS seems quite obvious.  Is there anything I
missed in the patch below? Is it good enough to commit?

This lets me discover that posix_fallocate() libc stub is buggy. Using
it through #include <unistd.h> leads argument corruption. Defining it as
int      posix_fallocate(int, int, off_t, off_t); let it work (note the
second int pad, as in syscalls.master). I guess we need to add a libc
stub too.

Index: sys/ufs/ffs/ffs_vnops.c
===================================================================
RCS file: /cvsroot/src/sys/ufs/ffs/ffs_vnops.c,v
retrieving revision 1.125
diff -U 4 -r1.125 ffs_vnops.c
--- sys/ufs/ffs/ffs_vnops.c     25 Jul 2014 08:20:53 -0000      1.125
+++ sys/ufs/ffs/ffs_vnops.c     25 Sep 2014 01:09:50 -0000
@@ -114,9 +114,9 @@
        { &vop_getattr_desc, ufs_getattr },             /* getattr */
        { &vop_setattr_desc, ufs_setattr },             /* setattr */
        { &vop_read_desc, ffs_read },                   /* read */
        { &vop_write_desc, ffs_write },                 /* write */
-       { &vop_fallocate_desc, genfs_eopnotsupp },      /* fallocate */
+       { &vop_fallocate_desc, ffs_fallocate },         /* fallocate */
        { &vop_fdiscard_desc, genfs_eopnotsupp },       /* fdiscard */
        { &vop_ioctl_desc, ufs_ioctl },                 /* ioctl */
        { &vop_fcntl_desc, ufs_fcntl },                 /* fcntl */
        { &vop_poll_desc, ufs_poll },                   /* poll */
@@ -326,8 +326,41 @@
        return error;
 }
 
 int
+ffs_fallocate(void *v)
+{
+       struct vop_fallocate_args /* {
+               struct vnode *a_vp;
+               off_t a_pos;
+               off_t a_len;
+       } */ *ap = v;
+       struct vnode *vp;
+       struct mount *mp;
+       int error;
+
+
+       vp = ap->a_vp;
+       mp = vp->v_mount;
+
+       fstrans_start(mp, FSTRANS_LAZY);
+       error = UFS_WAPBL_BEGIN(vp->v_mount);
+       if (error)
+               goto out;
+
+       genfs_node_wrlock(vp);
+       error = GOP_ALLOC(vp, ap->a_pos, ap->a_len, 0, curlwp->l_cred);
+       genfs_node_unlock(vp);
+
+       UFS_WAPBL_UPDATE(vp, NULL, NULL, 0);
+       UFS_WAPBL_END(vp->v_mount);
+out:
+       fstrans_done(mp);
+
+       return error;
+}
+
+int
 ffs_fsync(void *v)
 {
        struct vop_fsync_args /* {
                struct vnode *a_vp;


-- 
Emmanuel Dreyfus
http://hcpnet.free.fr/pubz
manu%netbsd.org@localhost