keep track of vnode size changes.
[unix-history] / usr / src / sys / miscfs / union / union_vnops.c
index 22cbdf5..f165b98 100644 (file)
@@ -8,7 +8,7 @@
  *
  * %sccs.include.redist.c%
  *
  *
  * %sccs.include.redist.c%
  *
- *     @(#)union_vnops.c       8.8 (Berkeley) %G%
+ *     @(#)union_vnops.c       8.10 (Berkeley) %G%
  */
 
 #include <sys/param.h>
  */
 
 #include <sys/param.h>
@@ -151,7 +151,7 @@ union_lookup(ap)
         * then assume that something special is going
         * on and just return that vnode.
         */
         * then assume that something special is going
         * on and just return that vnode.
         */
-       if (upperdvp) {
+       if (upperdvp != NULLVP) {
                FIXUP(dun);
                uerror = union_lookup1(um->um_uppervp, &upperdvp,
                                        &uppervp, cnp);
                FIXUP(dun);
                uerror = union_lookup1(um->um_uppervp, &upperdvp,
                                        &uppervp, cnp);
@@ -175,7 +175,7 @@ union_lookup(ap)
         * back from the upper layer and return the lower vnode
         * instead.
         */
         * back from the upper layer and return the lower vnode
         * instead.
         */
-       if (lowerdvp) {
+       if (lowerdvp != NULLVP) {
                int nameiop;
 
                VOP_LOCK(lowerdvp);
                int nameiop;
 
                VOP_LOCK(lowerdvp);
@@ -200,7 +200,7 @@ union_lookup(ap)
                        VOP_UNLOCK(lowerdvp);
 
                if (cnp->cn_consume != 0) {
                        VOP_UNLOCK(lowerdvp);
 
                if (cnp->cn_consume != 0) {
-                       if (uppervp) {
+                       if (uppervp != NULLVP) {
                                if (uppervp == upperdvp)
                                        vrele(uppervp);
                                else
                                if (uppervp == upperdvp)
                                        vrele(uppervp);
                                else
@@ -260,7 +260,7 @@ union_lookup(ap)
                        dun->un_flags |= UN_ULOCK;
 
                        if (uerror) {
                        dun->un_flags |= UN_ULOCK;
 
                        if (uerror) {
-                               if (lowervp) {
+                               if (lowervp != NULLVP) {
                                        vput(lowervp);
                                        lowervp = NULLVP;
                                }
                                        vput(lowervp);
                                        lowervp = NULLVP;
                                }
@@ -269,16 +269,16 @@ union_lookup(ap)
                }
        }
 
                }
        }
 
-       if (lowervp)
+       if (lowervp != NULLVP)
                VOP_UNLOCK(lowervp);
 
        error = union_allocvp(ap->a_vpp, dvp->v_mount, dvp, upperdvp, cnp,
                              uppervp, lowervp);
 
        if (error) {
                VOP_UNLOCK(lowervp);
 
        error = union_allocvp(ap->a_vpp, dvp->v_mount, dvp, upperdvp, cnp,
                              uppervp, lowervp);
 
        if (error) {
-               if (uppervp)
+               if (uppervp != NULLVP)
                        vput(uppervp);
                        vput(uppervp);
-               if (lowervp)
+               if (lowervp != NULLVP)
                        vrele(lowervp);
        } else {
                if (*ap->a_vpp != dvp)
                        vrele(lowervp);
        } else {
                if (*ap->a_vpp != dvp)
@@ -301,7 +301,7 @@ union_create(ap)
        struct union_node *un = VTOUNION(ap->a_dvp);
        struct vnode *dvp = un->un_uppervp;
 
        struct union_node *un = VTOUNION(ap->a_dvp);
        struct vnode *dvp = un->un_uppervp;
 
-       if (dvp) {
+       if (dvp != NULLVP) {
                int error;
                struct vnode *vp;
 
                int error;
                struct vnode *vp;
 
@@ -343,7 +343,7 @@ union_mknod(ap)
        struct union_node *un = VTOUNION(ap->a_dvp);
        struct vnode *dvp = un->un_uppervp;
 
        struct union_node *un = VTOUNION(ap->a_dvp);
        struct vnode *dvp = un->un_uppervp;
 
-       if (dvp) {
+       if (dvp != NULLVP) {
                int error;
                struct vnode *vp;
 
                int error;
                struct vnode *vp;
 
@@ -356,7 +356,7 @@ union_mknod(ap)
                if (error)
                        return (error);
 
                if (error)
                        return (error);
 
-               if (vp) {
+               if (vp != NULLVP) {
                        error = union_allocvp(
                                        ap->a_vpp,
                                        ap->a_dvp->v_mount,
                        error = union_allocvp(
                                        ap->a_vpp,
                                        ap->a_dvp->v_mount,
@@ -510,7 +510,7 @@ union_close(ap)
        struct union_node *un = VTOUNION(ap->a_vp);
        struct vnode *vp;
 
        struct union_node *un = VTOUNION(ap->a_vp);
        struct vnode *vp;
 
-       if (un->un_uppervp) {
+       if (un->un_uppervp != NULLVP) {
                vp = un->un_uppervp;
        } else {
 #ifdef UNION_DIAGNOSTIC
                vp = un->un_uppervp;
        } else {
 #ifdef UNION_DIAGNOSTIC
@@ -546,12 +546,12 @@ union_access(ap)
        int error = EACCES;
        struct vnode *vp;
 
        int error = EACCES;
        struct vnode *vp;
 
-       if (vp = un->un_uppervp) {
+       if ((vp = un->un_uppervp) != NULLVP) {
                FIXUP(un);
                return (VOP_ACCESS(vp, ap->a_mode, ap->a_cred, ap->a_p));
        }
 
                FIXUP(un);
                return (VOP_ACCESS(vp, ap->a_mode, ap->a_cred, ap->a_p));
        }
 
-       if (vp = un->un_lowervp) {
+       if ((vp = un->un_lowervp) != NULLVP) {
                VOP_LOCK(vp);
                error = VOP_ACCESS(vp, ap->a_mode, ap->a_cred, ap->a_p);
                if (error == 0) {
                VOP_LOCK(vp);
                error = VOP_ACCESS(vp, ap->a_mode, ap->a_cred, ap->a_p);
                if (error == 0) {
@@ -570,7 +570,8 @@ union_access(ap)
 }
 
 /*
 }
 
 /*
- *  We handle getattr only to change the fsid.
+ * We handle getattr only to change the fsid and
+ * track object sizes
  */
 int
 union_getattr(ap)
  */
 int
 union_getattr(ap)
@@ -615,6 +616,7 @@ union_getattr(ap)
                error = VOP_GETATTR(vp, vap, ap->a_cred, ap->a_p);
                if (error)
                        return (error);
                error = VOP_GETATTR(vp, vap, ap->a_cred, ap->a_p);
                if (error)
                        return (error);
+               union_newsize(ap->a_vp, vap->va_size, VNOVAL);
        }
 
        if (vp == NULLVP) {
        }
 
        if (vp == NULLVP) {
@@ -632,6 +634,7 @@ union_getattr(ap)
                VOP_UNLOCK(vp);
                if (error)
                        return (error);
                VOP_UNLOCK(vp);
                if (error)
                        return (error);
+               union_newsize(ap->a_vp, VNOVAL, vap->va_size);
        }
 
        if ((vap != ap->a_vap) && (vap->va_type == VDIR))
        }
 
        if ((vap != ap->a_vap) && (vap->va_type == VDIR))
@@ -685,6 +688,8 @@ union_setattr(ap)
                FIXUP(un);
                error = VOP_SETATTR(un->un_uppervp, ap->a_vap,
                                        ap->a_cred, ap->a_p);
                FIXUP(un);
                error = VOP_SETATTR(un->un_uppervp, ap->a_vap,
                                        ap->a_cred, ap->a_p);
+               if ((error == 0) && (ap->a_vap->va_size != VNOVAL))
+                       union_newsize(ap->a_vp, ap->a_vap->va_size, VNOVAL);
        } else {
                error = EROFS;
        }
        } else {
                error = EROFS;
        }
@@ -713,6 +718,25 @@ union_read(ap)
        if (dolock)
                VOP_UNLOCK(vp);
 
        if (dolock)
                VOP_UNLOCK(vp);
 
+       /*
+        * XXX
+        * perhaps the size of the underlying object has changed under
+        * our feet.  take advantage of the offset information present
+        * in the uio structure.
+        */
+       if (error == 0) {
+               struct union_node *un = VTOUNION(ap->a_vp);
+               off_t cur = ap->a_uio->uio_offset;
+
+               if (vp == un->un_uppervp) {
+                       if (cur > un->un_uppersz)
+                               union_newsize(ap->a_vp, cur, VNOVAL);
+               } else {
+                       if (cur > un->un_lowersz)
+                               union_newsize(ap->a_vp, VNOVAL, cur);
+               }
+       }
+
        return (error);
 }
 
        return (error);
 }
 
@@ -737,6 +761,23 @@ union_write(ap)
        if (dolock)
                VOP_UNLOCK(vp);
 
        if (dolock)
                VOP_UNLOCK(vp);
 
+       /*
+        * the size of the underlying object may be changed by the
+        * write.
+        */
+       if (error == 0) {
+               struct union_node *un = VTOUNION(ap->a_vp);
+               off_t cur = ap->a_uio->uio_offset;
+
+               if (vp == un->un_uppervp) {
+                       if (cur > un->un_uppersz)
+                               union_newsize(ap->a_vp, cur, VNOVAL);
+               } else {
+                       if (cur > un->un_lowersz)
+                               union_newsize(ap->a_vp, VNOVAL, cur);
+               }
+       }
+
        return (error);
 }
 
        return (error);
 }
 
@@ -797,7 +838,7 @@ union_fsync(ap)
        int error = 0;
        struct vnode *targetvp = OTHERVP(ap->a_vp);
 
        int error = 0;
        struct vnode *targetvp = OTHERVP(ap->a_vp);
 
-       if (targetvp) {
+       if (targetvp != NULLVP) {
                int dolock = (targetvp == LOWERVP(ap->a_vp));
 
                if (dolock)
                int dolock = (targetvp == LOWERVP(ap->a_vp));
 
                if (dolock)
@@ -838,7 +879,7 @@ union_remove(ap)
        struct union_node *dun = VTOUNION(ap->a_dvp);
        struct union_node *un = VTOUNION(ap->a_vp);
 
        struct union_node *dun = VTOUNION(ap->a_dvp);
        struct union_node *un = VTOUNION(ap->a_vp);
 
-       if (dun->un_uppervp && un->un_uppervp) {
+       if (dun->un_uppervp != NULLVP && un->un_uppervp != NULLVP) {
                struct vnode *dvp = dun->un_uppervp;
                struct vnode *vp = un->un_uppervp;
 
                struct vnode *dvp = dun->un_uppervp;
                struct vnode *vp = un->un_uppervp;
 
@@ -882,7 +923,7 @@ union_link(ap)
        struct union_node *dun = VTOUNION(ap->a_vp);
        struct union_node *un = VTOUNION(ap->a_tdvp);
 
        struct union_node *dun = VTOUNION(ap->a_vp);
        struct union_node *un = VTOUNION(ap->a_tdvp);
 
-       if (dun->un_uppervp && un->un_uppervp) {
+       if (dun->un_uppervp != NULLVP && un->un_uppervp != NULLVP) {
                struct vnode *dvp = dun->un_uppervp;
                struct vnode *vp = un->un_uppervp;
 
                struct vnode *dvp = dun->un_uppervp;
                struct vnode *vp = un->un_uppervp;
 
@@ -897,7 +938,7 @@ union_link(ap)
                error = VOP_LINK(dvp, vp, ap->a_cnp);
        } else {
                /*
                error = VOP_LINK(dvp, vp, ap->a_cnp);
        } else {
                /*
-                * XXX: need to copy to upper layer
+                * XXX: perhaps could copy to upper layer
                 * and do the link there.
                 */
                vput(ap->a_vp);
                 * and do the link there.
                 */
                vput(ap->a_vp);
@@ -933,7 +974,6 @@ union_rename(ap)
                        goto bad;
                }
 
                        goto bad;
                }
 
-               FIXUP(un);
                fdvp = un->un_uppervp;
                VREF(fdvp);
                vrele(ap->a_fdvp);
                fdvp = un->un_uppervp;
                VREF(fdvp);
                vrele(ap->a_fdvp);
@@ -946,7 +986,6 @@ union_rename(ap)
                        goto bad;
                }
 
                        goto bad;
                }
 
-               FIXUP(un);
                fvp = un->un_uppervp;
                VREF(fvp);
                vrele(ap->a_fvp);
                fvp = un->un_uppervp;
                VREF(fvp);
                vrele(ap->a_fvp);
@@ -955,6 +994,12 @@ union_rename(ap)
        if (tdvp->v_op == union_vnodeop_p) {
                struct union_node *un = VTOUNION(tdvp);
                if (un->un_uppervp == NULLVP) {
        if (tdvp->v_op == union_vnodeop_p) {
                struct union_node *un = VTOUNION(tdvp);
                if (un->un_uppervp == NULLVP) {
+                       /*
+                        * this should never happen in normal
+                        * operation but might if there was
+                        * a problem creating the top-level shadow
+                        * directory.
+                        */
                        error = EROFS;
                        goto bad;
                }
                        error = EROFS;
                        goto bad;
                }
@@ -965,16 +1010,14 @@ union_rename(ap)
                vput(ap->a_tdvp);
        }
 
                vput(ap->a_tdvp);
        }
 
-       if (tvp && tvp->v_op == union_vnodeop_p) {
+       if (tvp != NULLVP && tvp->v_op == union_vnodeop_p) {
                struct union_node *un = VTOUNION(tvp);
                struct union_node *un = VTOUNION(tvp);
-               if (un->un_uppervp == NULLVP) {
-                       error = EROFS;
-                       goto bad;
-               }
 
                tvp = un->un_uppervp;
 
                tvp = un->un_uppervp;
-               VREF(tvp);
-               un->un_flags |= UN_KLOCK;
+               if (tvp != NULLVP) {
+                       VREF(tvp);
+                       un->un_flags |= UN_KLOCK;
+               }
                vput(ap->a_tvp);
        }
 
                vput(ap->a_tvp);
        }
 
@@ -984,7 +1027,7 @@ bad:
        vrele(fdvp);
        vrele(fvp);
        vput(tdvp);
        vrele(fdvp);
        vrele(fvp);
        vput(tdvp);
-       if (tvp)
+       if (tvp != NULLVP)
                vput(tvp);
 
        return (error);
                vput(tvp);
 
        return (error);
@@ -1002,7 +1045,7 @@ union_mkdir(ap)
        struct union_node *un = VTOUNION(ap->a_dvp);
        struct vnode *dvp = un->un_uppervp;
 
        struct union_node *un = VTOUNION(ap->a_dvp);
        struct vnode *dvp = un->un_uppervp;
 
-       if (dvp) {
+       if (dvp != NULLVP) {
                int error;
                struct vnode *vp;
 
                int error;
                struct vnode *vp;
 
@@ -1043,7 +1086,7 @@ union_rmdir(ap)
        struct union_node *dun = VTOUNION(ap->a_dvp);
        struct union_node *un = VTOUNION(ap->a_vp);
 
        struct union_node *dun = VTOUNION(ap->a_dvp);
        struct union_node *un = VTOUNION(ap->a_vp);
 
-       if (dun->un_uppervp && un->un_uppervp) {
+       if (dun->un_uppervp != NULLVP && un->un_uppervp != NULLVP) {
                struct vnode *dvp = dun->un_uppervp;
                struct vnode *vp = un->un_uppervp;
 
                struct vnode *dvp = dun->un_uppervp;
                struct vnode *vp = un->un_uppervp;
 
@@ -1088,7 +1131,7 @@ union_symlink(ap)
        struct union_node *un = VTOUNION(ap->a_dvp);
        struct vnode *dvp = un->un_uppervp;
 
        struct union_node *un = VTOUNION(ap->a_dvp);
        struct vnode *dvp = un->un_uppervp;
 
-       if (dvp) {
+       if (dvp != NULLVP) {
                int error;
                struct vnode *vp;
                struct mount *mp = ap->a_dvp->v_mount;
                int error;
                struct vnode *vp;
                struct mount *mp = ap->a_dvp->v_mount;
@@ -1126,7 +1169,7 @@ union_readdir(ap)
        int error = 0;
        struct union_node *un = VTOUNION(ap->a_vp);
 
        int error = 0;
        struct union_node *un = VTOUNION(ap->a_vp);
 
-       if (un->un_uppervp) {
+       if (un->un_uppervp != NULLVP) {
                FIXUP(un);
                error = VOP_READDIR(un->un_uppervp, ap->a_uio, ap->a_cred);
        }
                FIXUP(un);
                error = VOP_READDIR(un->un_uppervp, ap->a_uio, ap->a_cred);
        }
@@ -1244,7 +1287,7 @@ start:
 
        un = VTOUNION(vp);
 
 
        un = VTOUNION(vp);
 
-       if (un->un_uppervp) {
+       if (un->un_uppervp != NULLVP) {
                if ((un->un_flags & UN_ULOCK) == 0) {
                        un->un_flags |= UN_ULOCK;
                        VOP_LOCK(un->un_uppervp);
                if ((un->un_flags & UN_ULOCK) == 0) {
                        un->un_flags |= UN_ULOCK;
                        VOP_LOCK(un->un_uppervp);