Update the statfs structure with 64-bit fields to allow

accurate reporting of multi-terabyte filesystem sizes.

You should build and boot a new kernel BEFORE doing a `make world'
as the new kernel will know about binaries using the old statfs
structure, but an old kernel will not know about the new system
calls that support the new statfs structure. Running an old kernel
after a `make world' will cause programs such as `df' that do a
statfs system call to fail with a bad system call.

Reviewed by:	Bruce Evans <bde@zeta.org.au>
Reviewed by:	Tim Robbins <tjr@freebsd.org>
Reviewed by:	Julian Elischer <julian@elischer.org>
Reviewed by:	the hoards of <arch@freebsd.org>
Sponsored by:   DARPA & NAI Labs.

1 files changed, 296 insertions, 13 deletions

diff --git a/sys/kern/vfs_syscalls.c b/sys/kern/vfs_syscalls.c
index 3783010..a8900dc 100644
--- a/sys/kern/vfs_syscalls.c
+++ b/sys/kern/vfs_syscalls.c
@@ -226,11 +226,10 @@ statfs(td, uap)
 		struct statfs *buf;
 	} */ *uap;
 {
-	register struct mount *mp;
-	register struct statfs *sp;
+	struct mount *mp;
+	struct statfs *sp, sb;
 	int error;
 	struct nameidata nd;
-	struct statfs sb;
 
 	NDINIT(&nd, LOOKUP, FOLLOW, UIO_USERSPACE, uap->path, td);
 	if ((error = namei(&nd)) != 0)
@@ -244,10 +243,15 @@ statfs(td, uap)
 	if (error)
 		return (error);
 #endif
+	/*
+	 * Set these in case the underlying filesystem fails to do so.
+	 */
+	sp->f_version = STATFS_VERSION;
+	sp->f_namemax = NAME_MAX;
+	sp->f_flags = mp->mnt_flag & MNT_VISFLAGMASK;
 	error = VFS_STATFS(mp, sp, td);
 	if (error)
 		return (error);
-	sp->f_flags = mp->mnt_flag & MNT_VISFLAGMASK;
 	if (suser(td)) {
 		bcopy(sp, &sb, sizeof(sb));
 		sb.f_fsid.val[0] = sb.f_fsid.val[1] = 0;
@@ -276,9 +280,8 @@ fstatfs(td, uap)
 {
 	struct file *fp;
 	struct mount *mp;
-	register struct statfs *sp;
+	struct statfs *sp, sb;
 	int error;
-	struct statfs sb;
 
 	if ((error = getvnode(td->td_proc->p_fd, uap->fd, &fp)) != 0)
 		return (error);
@@ -292,10 +295,15 @@ fstatfs(td, uap)
 		return (error);
 #endif
 	sp = &mp->mnt_stat;
+	/*
+	 * Set these in case the underlying filesystem fails to do so.
+	 */
+	sp->f_version = STATFS_VERSION;
+	sp->f_namemax = NAME_MAX;
+	sp->f_flags = mp->mnt_flag & MNT_VISFLAGMASK;
 	error = VFS_STATFS(mp, sp, td);
 	if (error)
 		return (error);
-	sp->f_flags = mp->mnt_flag & MNT_VISFLAGMASK;
 	if (suser(td)) {
 		bcopy(sp, &sb, sizeof(sb));
 		sb.f_fsid.val[0] = sb.f_fsid.val[1] = 0;
@@ -323,8 +331,8 @@ getfsstat(td, uap)
 		int flags;
 	} */ *uap;
 {
-	register struct mount *mp, *nmp;
-	register struct statfs *sp;
+	struct mount *mp, *nmp;
+	struct statfs *sp, sb;
 	caddr_t sfsp;
 	long count, maxcount, error;
 
@@ -346,6 +354,13 @@ getfsstat(td, uap)
 		if (sfsp && count < maxcount) {
 			sp = &mp->mnt_stat;
 			/*
+			 * Set these in case the underlying filesystem
+			 * fails to do so.
+			 */
+			sp->f_version = STATFS_VERSION;
+			sp->f_namemax = NAME_MAX;
+			sp->f_flags = mp->mnt_flag & MNT_VISFLAGMASK;
+			/*
 			 * If MNT_NOWAIT or MNT_LAZY is specified, do not
 			 * refresh the fsstat cache. MNT_NOWAIT or MNT_LAZY
 			 * overrides MNT_WAIT.
@@ -358,7 +373,11 @@ getfsstat(td, uap)
 				vfs_unbusy(mp, td);
 				continue;
 			}
-			sp->f_flags = mp->mnt_flag & MNT_VISFLAGMASK;
+			if (suser(td)) {
+				bcopy(sp, &sb, sizeof(sb));
+				sb.f_fsid.val[0] = sb.f_fsid.val[1] = 0;
+				sp = &sb;
+			}
 			error = copyout(sp, sfsp, sizeof(*sp));
 			if (error) {
 				vfs_unbusy(mp, td);
@@ -379,6 +398,266 @@ getfsstat(td, uap)
 	return (0);
 }
 
+#ifdef COMPAT_FREEBSD4
+/*
+ * Get old format filesystem statistics.
+ */
+static void cvtstatfs(struct thread *, struct statfs *, struct ostatfs *);
+
+#ifndef _SYS_SYSPROTO_H_
+struct freebsd4_statfs_args {
+	char *path;
+	struct ostatfs *buf;
+};
+#endif
+/* ARGSUSED */
+int
+freebsd4_statfs(td, uap)
+	struct thread *td;
+	struct freebsd4_statfs_args /* {
+		char *path;
+		struct ostatfs *buf;
+	} */ *uap;
+{
+	struct mount *mp;
+	struct statfs *sp;
+	struct ostatfs osb;
+	int error;
+	struct nameidata nd;
+
+	NDINIT(&nd, LOOKUP, FOLLOW, UIO_USERSPACE, uap->path, td);
+	if ((error = namei(&nd)) != 0)
+		return (error);
+	mp = nd.ni_vp->v_mount;
+	sp = &mp->mnt_stat;
+	NDFREE(&nd, NDF_ONLY_PNBUF);
+	vrele(nd.ni_vp);
+#ifdef MAC
+	error = mac_check_mount_stat(td->td_ucred, mp);
+	if (error)
+		return (error);
+#endif
+	error = VFS_STATFS(mp, sp, td);
+	if (error)
+		return (error);
+	sp->f_flags = mp->mnt_flag & MNT_VISFLAGMASK;
+	cvtstatfs(td, sp, &osb);
+	return (copyout(&osb, uap->buf, sizeof(osb)));
+}
+
+/*
+ * Get filesystem statistics.
+ */
+#ifndef _SYS_SYSPROTO_H_
+struct freebsd4_fstatfs_args {
+	int fd;
+	struct ostatfs *buf;
+};
+#endif
+/* ARGSUSED */
+int
+freebsd4_fstatfs(td, uap)
+	struct thread *td;
+	struct freebsd4_fstatfs_args /* {
+		int fd;
+		struct ostatfs *buf;
+	} */ *uap;
+{
+	struct file *fp;
+	struct mount *mp;
+	struct statfs *sp;
+	struct ostatfs osb;
+	int error;
+
+	if ((error = getvnode(td->td_proc->p_fd, uap->fd, &fp)) != 0)
+		return (error);
+	mp = fp->f_vnode->v_mount;
+	fdrop(fp, td);
+	if (mp == NULL)
+		return (EBADF);
+#ifdef MAC
+	error = mac_check_mount_stat(td->td_ucred, mp);
+	if (error)
+		return (error);
+#endif
+	sp = &mp->mnt_stat;
+	error = VFS_STATFS(mp, sp, td);
+	if (error)
+		return (error);
+	sp->f_flags = mp->mnt_flag & MNT_VISFLAGMASK;
+	cvtstatfs(td, sp, &osb);
+	return (copyout(&osb, uap->buf, sizeof(osb)));
+}
+
+/*
+ * Get statistics on all filesystems.
+ */
+#ifndef _SYS_SYSPROTO_H_
+struct freebsd4_getfsstat_args {
+	struct ostatfs *buf;
+	long bufsize;
+	int flags;
+};
+#endif
+int
+freebsd4_getfsstat(td, uap)
+	struct thread *td;
+	register struct freebsd4_getfsstat_args /* {
+		struct ostatfs *buf;
+		long bufsize;
+		int flags;
+	} */ *uap;
+{
+	struct mount *mp, *nmp;
+	struct statfs *sp;
+	struct ostatfs osb;
+	caddr_t sfsp;
+	long count, maxcount, error;
+
+	maxcount = uap->bufsize / sizeof(struct ostatfs);
+	sfsp = (caddr_t)uap->buf;
+	count = 0;
+	mtx_lock(&mountlist_mtx);
+	for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) {
+#ifdef MAC
+		if (mac_check_mount_stat(td->td_ucred, mp) != 0) {
+			nmp = TAILQ_NEXT(mp, mnt_list);
+			continue;
+		}
+#endif
+		if (vfs_busy(mp, LK_NOWAIT, &mountlist_mtx, td)) {
+			nmp = TAILQ_NEXT(mp, mnt_list);
+			continue;
+		}
+		if (sfsp && count < maxcount) {
+			sp = &mp->mnt_stat;
+			/*
+			 * If MNT_NOWAIT or MNT_LAZY is specified, do not
+			 * refresh the fsstat cache. MNT_NOWAIT or MNT_LAZY
+			 * overrides MNT_WAIT.
+			 */
+			if (((uap->flags & (MNT_LAZY|MNT_NOWAIT)) == 0 ||
+			    (uap->flags & MNT_WAIT)) &&
+			    (error = VFS_STATFS(mp, sp, td))) {
+				mtx_lock(&mountlist_mtx);
+				nmp = TAILQ_NEXT(mp, mnt_list);
+				vfs_unbusy(mp, td);
+				continue;
+			}
+			sp->f_flags = mp->mnt_flag & MNT_VISFLAGMASK;
+			cvtstatfs(td, sp, &osb);
+			error = copyout(&osb, sfsp, sizeof(osb));
+			if (error) {
+				vfs_unbusy(mp, td);
+				return (error);
+			}
+			sfsp += sizeof(osb);
+		}
+		count++;
+		mtx_lock(&mountlist_mtx);
+		nmp = TAILQ_NEXT(mp, mnt_list);
+		vfs_unbusy(mp, td);
+	}
+	mtx_unlock(&mountlist_mtx);
+	if (sfsp && count > maxcount)
+		td->td_retval[0] = maxcount;
+	else
+		td->td_retval[0] = count;
+	return (0);
+}
+
+/*
+ * Implement fstatfs() for (NFS) file handles.
+ */
+#ifndef _SYS_SYSPROTO_H_
+struct freebsd4_fhstatfs_args {
+	struct fhandle *u_fhp;
+	struct ostatfs *buf;
+};
+#endif
+int
+freebsd4_fhstatfs(td, uap)
+	struct thread *td;
+	struct freebsd4_fhstatfs_args /* {
+		struct fhandle *u_fhp;
+		struct ostatfs *buf;
+	} */ *uap;
+{
+	struct statfs *sp;
+	struct mount *mp;
+	struct vnode *vp;
+	struct ostatfs osb;
+	fhandle_t fh;
+	int error;
+
+	/*
+	 * Must be super user
+	 */
+	error = suser(td);
+	if (error)
+		return (error);
+
+	if ((error = copyin(uap->u_fhp, &fh, sizeof(fhandle_t))) != 0)
+		return (error);
+
+	if ((mp = vfs_getvfs(&fh.fh_fsid)) == NULL)
+		return (ESTALE);
+	if ((error = VFS_FHTOVP(mp, &fh.fh_fid, &vp)))
+		return (error);
+	mp = vp->v_mount;
+	sp = &mp->mnt_stat;
+	vput(vp);
+#ifdef MAC
+	error = mac_check_mount_stat(td->td_ucred, mp);
+	if (error)
+		return (error);
+#endif
+	if ((error = VFS_STATFS(mp, sp, td)) != 0)
+		return (error);
+	sp->f_flags = mp->mnt_flag & MNT_VISFLAGMASK;
+	cvtstatfs(td, sp, &osb);
+	return (copyout(&osb, uap->buf, sizeof(osb)));
+}
+
+/*
+ * Convert a new format statfs structure to an old format statfs structure.
+ */
+static void
+cvtstatfs(td, nsp, osp)
+	struct thread *td;
+	struct statfs *nsp;
+	struct ostatfs *osp;
+{
+
+	bzero(osp, sizeof(*osp));
+	osp->f_bsize = MIN(nsp->f_bsize, LONG_MAX);
+	osp->f_iosize = MIN(nsp->f_iosize, LONG_MAX);
+	osp->f_blocks = MIN(nsp->f_blocks, LONG_MAX);
+	osp->f_bfree = MIN(nsp->f_bfree, LONG_MAX);
+	osp->f_bavail = MIN(nsp->f_bavail, LONG_MAX);
+	osp->f_files = MIN(nsp->f_files, LONG_MAX);
+	osp->f_ffree = MIN(nsp->f_ffree, LONG_MAX);
+	osp->f_owner = nsp->f_owner;
+	osp->f_type = nsp->f_type;
+	osp->f_flags = nsp->f_flags;
+	osp->f_syncwrites = MIN(nsp->f_syncwrites, LONG_MAX);
+	osp->f_asyncwrites = MIN(nsp->f_asyncwrites, LONG_MAX);
+	osp->f_syncreads = MIN(nsp->f_syncreads, LONG_MAX);
+	osp->f_asyncreads = MIN(nsp->f_asyncreads, LONG_MAX);
+	bcopy(nsp->f_fstypename, osp->f_fstypename,
+	    MIN(MFSNAMELEN, OMNAMELEN));
+	bcopy(nsp->f_mntonname, osp->f_mntonname,
+	    MIN(MFSNAMELEN, OMNAMELEN));
+	bcopy(nsp->f_mntfromname, osp->f_mntfromname,
+	    MIN(MFSNAMELEN, OMNAMELEN));
+	if (suser(td)) {
+		osp->f_fsid.val[0] = osp->f_fsid.val[1] = 0;
+	} else {
+		osp->f_fsid = nsp->f_fsid;
+	}
+}
+#endif /* COMPAT_FREEBSD4 */
+
 /*
  * Change current working directory to a given file descriptor.
  */
@@ -3788,10 +4067,9 @@ fhstatfs(td, uap)
 		struct statfs *buf;
 	} */ *uap;
 {
-	struct statfs *sp;
+	struct statfs *sp, sb;
 	struct mount *mp;
 	struct vnode *vp;
-	struct statfs sb;
 	fhandle_t fh;
 	int error;
 
@@ -3817,9 +4095,14 @@ fhstatfs(td, uap)
 	if (error)
 		return (error);
 #endif
+	/*
+	 * Set these in case the underlying filesystem fails to do so.
+	 */
+	sp->f_version = STATFS_VERSION;
+	sp->f_namemax = NAME_MAX;
+	sp->f_flags = mp->mnt_flag & MNT_VISFLAGMASK;
 	if ((error = VFS_STATFS(mp, sp, td)) != 0)
 		return (error);
-	sp->f_flags = mp->mnt_flag & MNT_VISFLAGMASK;
 	if (suser(td)) {
 		bcopy(sp, &sb, sizeof(sb));
 		sb.f_fsid.val[0] = sb.f_fsid.val[1] = 0;