have to protect acct_process from acctwatch closing the vnode

[unix-history] / usr / src / sys / kern / kern_acct.c

diff --git a/usr/src/sys/kern/kern_acct.c b/usr/src/sys/kern/kern_acct.c
index ebe0305..235c2e0 100644 (file)
--- a/usr/src/sys/kern/kern_acct.c
+++ b/usr/src/sys/kern/kern_acct.c
@@ -1,32 +1,38 @@
-/*
- * Copyright (c) 1982, 1986, 1989 Regents of the University of California.
- * All rights reserved.  The Berkeley software License Agreement
- * specifies the terms and conditions for redistribution.
+/*-
+ * Copyright (c) 1982, 1986, 1989, 1993
+ *     The Regents of the University of California.  All rights reserved.
+ * (c) UNIX System Laboratories, Inc.
+ * All or some portions of this file are derived from material licensed
+ * to the University of California by American Telephone and Telegraph
+ * Co. or Unix System Laboratories, Inc. and are reproduced herein with
+ * the permission of UNIX System Laboratories, Inc.
+ *
+ * %sccs.include.proprietary.c%

  *
  *

- *     @(#)kern_acct.c 7.13 (Berkeley) %G%
+ *     @(#)kern_acct.c 8.6 (Berkeley) %G%

  */
 
  */
 

-#include "param.h"
-#include "systm.h"
-#include "time.h"
-#include "proc.h"
-#include "ioctl.h"
-#include "termios.h"
-#include "tty.h"
-#include "user.h"
-#include "vnode.h"
-#include "mount.h"
-#include "kernel.h"
-#include "acct.h"
-#include "uio.h"
-#include "syslog.h"
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/namei.h>
+#include <sys/resourcevar.h>
+#include <sys/proc.h>
+#include <sys/ioctl.h>
+#include <sys/termios.h>
+#include <sys/tty.h>
+#include <sys/vnode.h>
+#include <sys/mount.h>
+#include <sys/kernel.h>
+#include <sys/file.h>
+#include <sys/acct.h>
+#include <sys/syslog.h>

 
 /*
  * Values associated with enabling and disabling accounting
  */
 int    acctsuspend = 2;        /* stop accounting when < 2% free space left */
 int    acctresume = 4;         /* resume when free space risen to > 4% */
 
 /*
  * Values associated with enabling and disabling accounting
  */
 int    acctsuspend = 2;        /* stop accounting when < 2% free space left */
 int    acctresume = 4;         /* resume when free space risen to > 4% */

-struct timeval chk = { 15, 0 };/* frequency to check space for accounting */
+int    acctchkfreq = 15;       /* frequency (in seconds) to check space */

 
 /*
  * SHOULD REPLACE THIS WITH A DRIVER THAT CAN BE READ TO SIMPLIFY.
 
 /*
  * SHOULD REPLACE THIS WITH A DRIVER THAT CAN BE READ TO SIMPLIFY.


@@ -35,130 +41,158 @@ struct    vnode *acctp;
 struct vnode *savacctp;
 
 /*
 struct vnode *savacctp;
 
 /*

- * Perform process accounting functions.
+ * Enable or disable process accounting.
+ *
+ * If a non-null filename is given, that file is used to store accounting
+ * records on process exit. If a null filename is given process accounting
+ * is suspended. If accounting is enabled, the system checks the amount
+ * of freespace on the filesystem at timeval intervals. If the amount of
+ * freespace is below acctsuspend percent, accounting is suspended. If
+ * accounting has been suspended, and freespace rises above acctresume,
+ * accounting is resumed.

  */
  */

-/* ARGSUSED */
-sysacct(p, uap, retval)
+struct acct_args {
+       char    *fname;
+};
+acct(p, uap, retval)

        struct proc *p;
        struct proc *p;

-       struct args {
-               char    *fname;
-       } *uap;
+       struct acct_args *uap;

        int *retval;
 {
        register struct vnode *vp;
        int *retval;
 {
        register struct vnode *vp;

-       register struct nameidata *ndp = &u.u_nd;
-       extern int acctwatch();
+       extern void acctwatch __P((void *));

        struct vnode *oacctp;
        int error;
        struct vnode *oacctp;
        int error;

+       struct nameidata nd;

 
 

-       if (error = suser(u.u_cred, &u.u_acflag))
+       if (error = suser(p->p_ucred, &p->p_acflag))

                return (error);
        if (savacctp) {
                acctp = savacctp;
                savacctp = NULL;
        }
                return (error);
        if (savacctp) {
                acctp = savacctp;
                savacctp = NULL;
        }

-       if (uap->fname==NULL) {
+       if (uap->fname == NULL) {

                if (vp = acctp) {
                        acctp = NULL;
                if (vp = acctp) {
                        acctp = NULL;

-                       vrele(vp);
-                       untimeout(acctwatch, (caddr_t)&chk);
+                       error = vn_close(vp, FWRITE, p->p_ucred, p);
+                       untimeout(acctwatch, NULL);

                }
                }

-               return (0);
+               return (error);

        }
        }

-       ndp->ni_nameiop = LOOKUP | FOLLOW;
-       ndp->ni_segflg = UIO_USERSPACE;
-       ndp->ni_dirp = uap->fname;
-       if (error = namei(ndp))
+       NDINIT(&nd, LOOKUP, FOLLOW, UIO_USERSPACE, uap->fname, p);
+       if (error = vn_open(&nd, FWRITE, 0644))

                return (error);
                return (error);

-       vp = ndp->ni_vp;
+       vp = nd.ni_vp;
+       VOP_UNLOCK(vp);

        if (vp->v_type != VREG) {
        if (vp->v_type != VREG) {

-               vrele(vp);
+               (void) vn_close(vp, FWRITE, p->p_ucred, p);

                return (EACCES);
        }
                return (EACCES);
        }

-       if (vp->v_mount->mnt_flag & MNT_RDONLY) {
-               vrele(vp);
-               return (EROFS);
-       }

        oacctp = acctp;
        acctp = vp;
        if (oacctp)
        oacctp = acctp;
        acctp = vp;
        if (oacctp)

-               vrele(oacctp);
-       acctwatch(&chk);
-       return (0);
+               error = vn_close(oacctp, FWRITE, p->p_ucred, p);
+       acctwatch(NULL);
+       return (error);

 }
 
 /*
  * Periodically check the file system to see if accounting
 }
 
 /*
  * Periodically check the file system to see if accounting

- * should be turned on or off.
+ * should be turned on or off. Beware the case where the vnode
+ * has been vgone()'d out from underneath us, e.g. when the file
+ * system containing the accounting file has been forcibly unmounted.

  */
  */

-acctwatch(resettime)
-       struct timeval *resettime;
+/* ARGSUSED */
+void
+acctwatch(a)
+       void *a;

 {
        struct statfs sb;
 
        if (savacctp) {
 {
        struct statfs sb;
 
        if (savacctp) {

-               (void)VFS_STATFS(savacctp->v_mount, &sb);
+               if (savacctp->v_type == VBAD) {
+                       (void) vn_close(savacctp, FWRITE, NOCRED, NULL);
+                       savacctp = NULL;
+                       return;
+               }
+               (void)VFS_STATFS(savacctp->v_mount, &sb, (struct proc *)0);

                if (sb.f_bavail > acctresume * sb.f_blocks / 100) {
                        acctp = savacctp;
                        savacctp = NULL;
                        log(LOG_NOTICE, "Accounting resumed\n");
                if (sb.f_bavail > acctresume * sb.f_blocks / 100) {
                        acctp = savacctp;
                        savacctp = NULL;
                        log(LOG_NOTICE, "Accounting resumed\n");

+               }
+       } else {
+               if (acctp == NULL)
+                       return;
+               if (acctp->v_type == VBAD) {
+                       (void) vn_close(acctp, FWRITE, NOCRED, NULL);
+                       acctp = NULL;

                        return;
                }
                        return;
                }

+               (void)VFS_STATFS(acctp->v_mount, &sb, (struct proc *)0);
+               if (sb.f_bavail <= acctsuspend * sb.f_blocks / 100) {
+                       savacctp = acctp;
+                       acctp = NULL;
+                       log(LOG_NOTICE, "Accounting suspended\n");
+               }

        }
        }

-       if (acctp == NULL)
-               return;
-       (void)VFS_STATFS(acctp->v_mount, &sb);
-       if (sb.f_bavail <= acctsuspend * sb.f_blocks / 100) {
-               savacctp = acctp;
-               acctp = NULL;
-               log(LOG_NOTICE, "Accounting suspended\n");
-       }
-       timeout(acctwatch, (caddr_t)resettime, hzto(resettime));
+       timeout(acctwatch, NULL, acctchkfreq * hz);

 }
 
 /*
 }
 
 /*

- * On exit, write a record on the accounting file.
+ * This routine calculates an accounting record for a process and,
+ * if accounting is enabled, writes it to the accounting file.

  */
  */

-acct(p)
+acct_process(p)

        register struct proc *p;
 {
        register struct rusage *ru;
        struct vnode *vp;
        struct timeval t, ut, st;
        register struct proc *p;
 {
        register struct rusage *ru;
        struct vnode *vp;
        struct timeval t, ut, st;

-       int i, s;
+       int error, i, s;

        struct acct acctbuf;
        register struct acct *ap = &acctbuf;
 
        struct acct acctbuf;
        register struct acct *ap = &acctbuf;
 

-       if ((vp = acctp) == NULL)
+       s = splclock();
+       if ((vp = acctp) == NULL) {
+               splx(s);

                return (0);
                return (0);

+       }
+       if (vp->v_type == VBAD) {
+               (void) vn_close(vp, FWRITE, NOCRED, NULL);
+               acctp = NULL;
+               splx(s);
+               return (0);
+       }

        bcopy(p->p_comm, ap->ac_comm, sizeof(ap->ac_comm));
        bcopy(p->p_comm, ap->ac_comm, sizeof(ap->ac_comm));

-       ru = &u.u_ru;
-       s = splclock();
-       ut = p->p_utime;
-       st = p->p_stime;
+       ru = &p->p_stats->p_ru;
+       calcru(p, &ut, &st, NULL);

        t = time;
        t = time;

-       splx(s);

        ap->ac_utime = compress(ut.tv_sec, ut.tv_usec);
        ap->ac_stime = compress(st.tv_sec, st.tv_usec);
        ap->ac_utime = compress(ut.tv_sec, ut.tv_usec);
        ap->ac_stime = compress(st.tv_sec, st.tv_usec);

-       timevalsub(&t, &u.u_start);
+       timevalsub(&t, &p->p_stats->p_start);

        ap->ac_etime = compress(t.tv_sec, t.tv_usec);
        ap->ac_etime = compress(t.tv_sec, t.tv_usec);

-       ap->ac_btime = u.u_start.tv_sec;
-       ap->ac_uid = p->p_ruid;
-       ap->ac_gid = p->p_rgid;
+       ap->ac_btime = p->p_stats->p_start.tv_sec;
+       ap->ac_uid = p->p_cred->p_ruid;
+       ap->ac_gid = p->p_cred->p_rgid;

        t = st;
        timevaladd(&t, &ut);
        if (i = t.tv_sec * hz + t.tv_usec / tick)
        t = st;
        timevaladd(&t, &ut);
        if (i = t.tv_sec * hz + t.tv_usec / tick)

-               ap->ac_mem = (ru->ru_ixrss+ru->ru_idrss+ru->ru_isrss) / i;
+               ap->ac_mem = (ru->ru_ixrss + ru->ru_idrss + ru->ru_isrss) / i;

        else
                ap->ac_mem = 0;
        ap->ac_io = compress(ru->ru_inblock + ru->ru_oublock, (long)0);
        else
                ap->ac_mem = 0;
        ap->ac_io = compress(ru->ru_inblock + ru->ru_oublock, (long)0);

-       if (p->p_flag&SCTTY && p->p_session->s_ttyp)
+       if (p->p_flag & P_CONTROLT && p->p_session->s_ttyp)

                ap->ac_tty = p->p_session->s_ttyp->t_dev;
        else
                ap->ac_tty = NODEV;
                ap->ac_tty = p->p_session->s_ttyp->t_dev;
        else
                ap->ac_tty = NODEV;

-       ap->ac_flag = u.u_acflag;
-       return (vn_rdwr(UIO_WRITE, vp, (caddr_t)ap, sizeof (acctbuf),
-               (off_t)0, UIO_SYSSPACE, IO_UNIT|IO_APPEND, u.u_cred, (int *)0));
+       ap->ac_flag = p->p_acflag;
+       VOP_LEASE(vp, p, p->p_ucred, LEASE_WRITE);
+       error = vn_rdwr(UIO_WRITE, vp, (caddr_t)ap, sizeof (acctbuf), (off_t)0,
+               UIO_SYSSPACE, IO_UNIT|IO_APPEND, p->p_ucred, (int *)0,
+               (struct proc *)0);
+       splx(s);
+       return (error);

 }
 
 /*
 }
 
 /*