FreeBSD/Linux Kernel Cross Reference
sys/coda/coda_vnops.c

     /*      $NetBSD: coda_vnops.c,v 1.68.22.1 2010/08/25 04:17:47 snj Exp $ */
     
     /*
      *
      *             Coda: an Experimental Distributed File System
      *                              Release 3.1
      *
      *           Copyright (c) 1987-1998 Carnegie Mellon University
      *                          All Rights Reserved
     *
     * Permission  to  use, copy, modify and distribute this software and its
     * documentation is hereby granted,  provided  that  both  the  copyright
     * notice  and  this  permission  notice  appear  in  all  copies  of the
     * software, derivative works or  modified  versions,  and  any  portions
     * thereof, and that both notices appear in supporting documentation, and
     * that credit is given to Carnegie Mellon University  in  all  documents
     * and publicity pertaining to direct or indirect use of this code or its
     * derivatives.
     *
     * CODA IS AN EXPERIMENTAL SOFTWARE SYSTEM AND IS  KNOWN  TO  HAVE  BUGS,
     * SOME  OF  WHICH MAY HAVE SERIOUS CONSEQUENCES.  CARNEGIE MELLON ALLOWS
     * FREE USE OF THIS SOFTWARE IN ITS "AS IS" CONDITION.   CARNEGIE  MELLON
     * DISCLAIMS  ANY  LIABILITY  OF  ANY  KIND  FOR  ANY  DAMAGES WHATSOEVER
     * RESULTING DIRECTLY OR INDIRECTLY FROM THE USE OF THIS SOFTWARE  OR  OF
     * ANY DERIVATIVE WORK.
     *
     * Carnegie  Mellon  encourages  users  of  this  software  to return any
     * improvements or extensions that  they  make,  and  to  grant  Carnegie
     * Mellon the rights to redistribute these changes without encumbrance.
     *
     *      @(#) coda/coda_vnops.c,v 1.1.1.1 1998/08/29 21:26:46 rvb Exp $
     */
    
    /*
     * Mach Operating System
     * Copyright (c) 1990 Carnegie-Mellon University
     * Copyright (c) 1989 Carnegie-Mellon University
     * All rights reserved.  The CMU software License Agreement specifies
     * the terms and conditions for use and redistribution.
     */
    
    /*
     * This code was written for the Coda file system at Carnegie Mellon
     * University.  Contributers include David Steere, James Kistler, and
     * M. Satyanarayanan.
     */
    
    #include <sys/cdefs.h>
    __KERNEL_RCSID(0, "$NetBSD: coda_vnops.c,v 1.68.22.1 2010/08/25 04:17:47 snj Exp $");
    
    #include <sys/param.h>
    #include <sys/systm.h>
    #include <sys/malloc.h>
    #include <sys/errno.h>
    #include <sys/acct.h>
    #include <sys/file.h>
    #include <sys/uio.h>
    #include <sys/namei.h>
    #include <sys/ioctl.h>
    #include <sys/mount.h>
    #include <sys/proc.h>
    #include <sys/select.h>
    #include <sys/user.h>
    #include <sys/vnode.h>
    #include <sys/kauth.h>
    
    #include <miscfs/genfs/genfs.h>
    
    #include <coda/coda.h>
    #include <coda/cnode.h>
    #include <coda/coda_vnops.h>
    #include <coda/coda_venus.h>
    #include <coda/coda_opstats.h>
    #include <coda/coda_subr.h>
    #include <coda/coda_namecache.h>
    #include <coda/coda_pioctl.h>
    
    /*
     * These flags select various performance enhancements.
     */
    int coda_attr_cache  = 1;       /* Set to cache attributes in the kernel */
    int coda_symlink_cache = 1;     /* Set to cache symbolic link information */
    int coda_access_cache = 1;      /* Set to handle some access checks directly */
    
    /* structure to keep track of vfs calls */
    
    struct coda_op_stats coda_vnodeopstats[CODA_VNODEOPS_SIZE];
    
    #define MARK_ENTRY(op) (coda_vnodeopstats[op].entries++)
    #define MARK_INT_SAT(op) (coda_vnodeopstats[op].sat_intrn++)
    #define MARK_INT_FAIL(op) (coda_vnodeopstats[op].unsat_intrn++)
    #define MARK_INT_GEN(op) (coda_vnodeopstats[op].gen_intrn++)
    
    /* What we are delaying for in printf */
    int coda_printf_delay = 0;  /* in microseconds */
    int coda_vnop_print_entry = 0;
    static int coda_lockdebug = 0;
    
    #define ENTRY if(coda_vnop_print_entry) myprintf(("Entered %s\n",__func__))
   
   /* Definition of the vnode operation vector */
   
   const struct vnodeopv_entry_desc coda_vnodeop_entries[] = {
       { &vop_default_desc, coda_vop_error },
       { &vop_lookup_desc, coda_lookup },          /* lookup */
       { &vop_create_desc, coda_create },          /* create */
       { &vop_mknod_desc, coda_vop_error },        /* mknod */
       { &vop_open_desc, coda_open },              /* open */
       { &vop_close_desc, coda_close },            /* close */
       { &vop_access_desc, coda_access },          /* access */
       { &vop_getattr_desc, coda_getattr },        /* getattr */
       { &vop_setattr_desc, coda_setattr },        /* setattr */
       { &vop_read_desc, coda_read },              /* read */
       { &vop_write_desc, coda_write },            /* write */
       { &vop_fcntl_desc, genfs_fcntl },           /* fcntl */
       { &vop_ioctl_desc, coda_ioctl },            /* ioctl */
       { &vop_mmap_desc, genfs_mmap },             /* mmap */
       { &vop_fsync_desc, coda_fsync },            /* fsync */
       { &vop_remove_desc, coda_remove },          /* remove */
       { &vop_link_desc, coda_link },              /* link */
       { &vop_rename_desc, coda_rename },          /* rename */
       { &vop_mkdir_desc, coda_mkdir },            /* mkdir */
       { &vop_rmdir_desc, coda_rmdir },            /* rmdir */
       { &vop_symlink_desc, coda_symlink },        /* symlink */
       { &vop_readdir_desc, coda_readdir },        /* readdir */
       { &vop_readlink_desc, coda_readlink },      /* readlink */
       { &vop_abortop_desc, coda_abortop },        /* abortop */
       { &vop_inactive_desc, coda_inactive },      /* inactive */
       { &vop_reclaim_desc, coda_reclaim },        /* reclaim */
       { &vop_lock_desc, coda_lock },              /* lock */
       { &vop_unlock_desc, coda_unlock },          /* unlock */
       { &vop_bmap_desc, coda_bmap },              /* bmap */
       { &vop_strategy_desc, coda_strategy },      /* strategy */
       { &vop_print_desc, coda_vop_error },        /* print */
       { &vop_islocked_desc, coda_islocked },      /* islocked */
       { &vop_pathconf_desc, coda_vop_error },     /* pathconf */
       { &vop_advlock_desc, coda_vop_nop },        /* advlock */
       { &vop_bwrite_desc, coda_vop_error },       /* bwrite */
       { &vop_seek_desc, genfs_seek },             /* seek */
       { &vop_poll_desc, genfs_poll },             /* poll */
       { &vop_getpages_desc, coda_getpages },      /* getpages */
       { &vop_putpages_desc, coda_putpages },      /* putpages */
       { NULL, NULL }
   };
   
   const struct vnodeopv_desc coda_vnodeop_opv_desc =
           { &coda_vnodeop_p, coda_vnodeop_entries };
   
   /* Definitions of NetBSD vnodeop interfaces */
   
   /*
    * A generic error routine.  Return EIO without looking at arguments.
    */
   int
   coda_vop_error(void *anon) {
       struct vnodeop_desc **desc = (struct vnodeop_desc **)anon;
   
       if (codadebug) {
           myprintf(("coda_vop_error: Vnode operation %s called (error).\n",
                     (*desc)->vdesc_name));
       }
   
       return EIO;
   }
   
   /* A generic do-nothing. */
   int
   coda_vop_nop(void *anon) {
       struct vnodeop_desc **desc = (struct vnodeop_desc **)anon;
   
       if (codadebug) {
           myprintf(("Vnode operation %s called, but unsupported\n",
                     (*desc)->vdesc_name));
       }
      return (0);
   }
   
   int
   coda_vnodeopstats_init(void)
   {
           int i;
   
           for(i=0;i<CODA_VNODEOPS_SIZE;i++) {
                   coda_vnodeopstats[i].opcode = i;
                   coda_vnodeopstats[i].entries = 0;
                   coda_vnodeopstats[i].sat_intrn = 0;
                   coda_vnodeopstats[i].unsat_intrn = 0;
                   coda_vnodeopstats[i].gen_intrn = 0;
           }
   
           return 0;
   }
   
   /*
    * XXX The entire relationship between VOP_OPEN and having a container
    * file (via venus_open) needs to be reexamined.  In particular, it's
    * valid to open/mmap/close and then reference.  Instead of doing
    * VOP_OPEN when getpages needs a container, we should do the
    * venus_open part, and record that the vnode has opened the container
    * for getpages, and do the matching logical close on coda_inactive.
    * Further, coda_rdwr needs a container file, and sometimes needs to
    * do the equivalent of open (core dumps).
    */
   /*
    * coda_open calls Venus to return the device and inode of the
    * container file, and then obtains a vnode for that file.  The
    * container vnode is stored in the coda vnode, and a reference is
    * added for each open file.
    */
   int
   coda_open(void *v)
   {
       /*
        * NetBSD can pass the O_EXCL flag in mode, even though the check
        * has already happened.  Venus defensively assumes that if open
        * is passed the EXCL, it must be a bug.  We strip the flag here.
        */
   /* true args */
       struct vop_open_args *ap = v;
       struct vnode *vp = ap->a_vp;
       struct cnode *cp = VTOC(vp);
       int flag = ap->a_mode & (~O_EXCL);
       kauth_cred_t cred = ap->a_cred;
   /* locals */
       int error;
       dev_t dev;                  /* container file device, inode, vnode */
       ino_t inode;
       struct vnode *container_vp;
   
       MARK_ENTRY(CODA_OPEN_STATS);
   
       /* Check for open of control file. */
       if (IS_CTL_VP(vp)) {
           /* if (WRITABLE(flag)) */
           if (flag & (FWRITE | O_TRUNC | O_CREAT | O_EXCL)) {
               MARK_INT_FAIL(CODA_OPEN_STATS);
               return(EACCES);
           }
           MARK_INT_SAT(CODA_OPEN_STATS);
           return(0);
       }
   
       error = venus_open(vtomi(vp), &cp->c_fid, flag, cred, curlwp, &dev, &inode);
       if (error)
           return (error);
       if (!error) {
           CODADEBUG(CODA_OPEN, myprintf(("open: dev %d inode %llu result %d\n",
                                     dev, (unsigned long long)inode, error)); )
       }
   
       /* 
        * Obtain locked and referenced container vnode from container
        * device/inode.
        */
       error = coda_grab_vnode(dev, inode, &container_vp);
       if (error)
           return (error);
   
       /* Save the vnode pointer for the container file. */
       if (cp->c_ovp == NULL) {
           cp->c_ovp = container_vp;
       } else {
           if (cp->c_ovp != container_vp)
               /*
                * Perhaps venus returned a different container, or
                * something else went wrong.
                */
               panic("coda_open: cp->c_ovp != container_vp");
       }
       cp->c_ocount++;
   
       /* Flush the attribute cache if writing the file. */
       if (flag & FWRITE) {
           cp->c_owrite++;
           cp->c_flags &= ~C_VATTR;
       }
   
       /* 
        * Save the <device, inode> pair for the container file to speed
        * up subsequent reads while closed (mmap, program execution).
        * This is perhaps safe because venus will invalidate the node
        * before changing the container file mapping.
        */
       cp->c_device = dev;
       cp->c_inode = inode;
   
       /* Open the container file. */
       error = VOP_OPEN(container_vp, flag, cred);
       /* 
        * Drop the lock on the container, after we have done VOP_OPEN
        * (which requires a locked vnode).
        */
       VOP_UNLOCK(container_vp, 0);
       return(error);
   }
   
   /*
    * Close the cache file used for I/O and notify Venus.
    */
   int
   coda_close(void *v)
   {
   /* true args */
       struct vop_close_args *ap = v;
       struct vnode *vp = ap->a_vp;
       struct cnode *cp = VTOC(vp);
       int flag = ap->a_fflag;
       kauth_cred_t cred = ap->a_cred;
   /* locals */
       int error;
   
       MARK_ENTRY(CODA_CLOSE_STATS);
   
       /* Check for close of control file. */
       if (IS_CTL_VP(vp)) {
           MARK_INT_SAT(CODA_CLOSE_STATS);
           return(0);
       }
   
       /*
        * XXX The IS_UNMOUNTING part of this is very suspect.
        */ 
       if (IS_UNMOUNTING(cp)) {
           if (cp->c_ovp) {
   #ifdef  CODA_VERBOSE
               printf("coda_close: destroying container ref %d, ufs vp %p of vp %p/cp %p\n",
                       vp->v_usecount, cp->c_ovp, vp, cp);
   #endif
   #ifdef  hmm
               vgone(cp->c_ovp);
   #else
               vn_lock(cp->c_ovp, LK_EXCLUSIVE | LK_RETRY);
               VOP_CLOSE(cp->c_ovp, flag, cred); /* Do errors matter here? */
               vput(cp->c_ovp);
   #endif
           } else {
   #ifdef  CODA_VERBOSE
               printf("coda_close: NO container vp %p/cp %p\n", vp, cp);
   #endif
           }
           return ENODEV;
       }
   
       /* Lock the container node, and VOP_CLOSE it. */
       vn_lock(cp->c_ovp, LK_EXCLUSIVE | LK_RETRY);
       VOP_CLOSE(cp->c_ovp, flag, cred); /* Do errors matter here? */
       /*
        * Drop the lock we just obtained, and vrele the container vnode.
        * Decrement reference counts, and clear container vnode pointer on
        * last close.
        */
       vput(cp->c_ovp);
       if (flag & FWRITE)
           --cp->c_owrite;
       if (--cp->c_ocount == 0)
           cp->c_ovp = NULL;
   
       error = venus_close(vtomi(vp), &cp->c_fid, flag, cred, curlwp);
   
       CODADEBUG(CODA_CLOSE, myprintf(("close: result %d\n",error)); )
       return(error);
   }
   
   int
   coda_read(void *v)
   {
       struct vop_read_args *ap = v;
   
       ENTRY;
       return(coda_rdwr(ap->a_vp, ap->a_uio, UIO_READ,
                       ap->a_ioflag, ap->a_cred, curlwp));
   }
   
   int
   coda_write(void *v)
   {
       struct vop_write_args *ap = v;
   
       ENTRY;
       return(coda_rdwr(ap->a_vp, ap->a_uio, UIO_WRITE,
                       ap->a_ioflag, ap->a_cred, curlwp));
   }
   
   int
   coda_rdwr(struct vnode *vp, struct uio *uiop, enum uio_rw rw, int ioflag,
           kauth_cred_t cred, struct lwp *l)
   {
   /* upcall decl */
     /* NOTE: container file operation!!! */
   /* locals */
       struct cnode *cp = VTOC(vp);
       struct vnode *cfvp = cp->c_ovp;
       struct proc *p = l->l_proc;
       int opened_internally = 0;
       int error = 0;
   
       MARK_ENTRY(CODA_RDWR_STATS);
   
       CODADEBUG(CODA_RDWR, myprintf(("coda_rdwr(%d, %p, %lu, %lld)\n", rw,
                                 uiop->uio_iov->iov_base,
                                 (unsigned long) uiop->uio_resid,
                                 (long long) uiop->uio_offset)); )
   
       /* Check for rdwr of control object. */
       if (IS_CTL_VP(vp)) {
           MARK_INT_FAIL(CODA_RDWR_STATS);
           return(EINVAL);
       }
   
       /* Redirect the request to UFS. */
   
       /*
        * If file is not already open this must be a page
        * {read,write} request.  Iget the cache file's inode
        * pointer if we still have its <device, inode> pair.
        * Otherwise, we must do an internal open to derive the
        * pair.
        * XXX Integrate this into a coherent strategy for container
        * file acquisition.
        */
       if (cfvp == NULL) {
           /*
            * If we're dumping core, do the internal open. Otherwise
            * venus won't have the correct size of the core when
            * it's completely written.
            */
           if (cp->c_inode != 0 && !(p && (p->p_acflag & ACORE))) {
               printf("coda_rdwr: grabbing container vnode, losing reference\n");
               /* Get locked and refed vnode. */
               error = coda_grab_vnode(cp->c_device, cp->c_inode, &cfvp);
               if (error) {
                   MARK_INT_FAIL(CODA_RDWR_STATS);
                   return(error);
               }
               /* 
                * Drop lock. 
                * XXX Where is reference released.
                */
               VOP_UNLOCK(cfvp, 0);
           }
           else {
               printf("coda_rdwr: internal VOP_OPEN\n");
               opened_internally = 1;
               MARK_INT_GEN(CODA_OPEN_STATS);
               error = VOP_OPEN(vp, (rw == UIO_READ ? FREAD : FWRITE), cred);
   #ifdef  CODA_VERBOSE
   printf("coda_rdwr: Internally Opening %p\n", vp);
   #endif
               if (error) {
                   MARK_INT_FAIL(CODA_RDWR_STATS);
                   return(error);
               }
               cfvp = cp->c_ovp;
           }
       }
   
       /* Have UFS handle the call. */
       CODADEBUG(CODA_RDWR, myprintf(("indirect rdwr: fid = %s, refcnt = %d\n",
                           coda_f2s(&cp->c_fid), CTOV(cp)->v_usecount)); )
   
       if (rw == UIO_READ) {
           error = VOP_READ(cfvp, uiop, ioflag, cred);
       } else {
           error = VOP_WRITE(cfvp, uiop, ioflag, cred);
       }
   
       if (error)
           MARK_INT_FAIL(CODA_RDWR_STATS);
       else
           MARK_INT_SAT(CODA_RDWR_STATS);
   
       /* Do an internal close if necessary. */
       if (opened_internally) {
           MARK_INT_GEN(CODA_CLOSE_STATS);
           (void)VOP_CLOSE(vp, (rw == UIO_READ ? FREAD : FWRITE), cred);
       }
   
       /* Invalidate cached attributes if writing. */
       if (rw == UIO_WRITE)
           cp->c_flags &= ~C_VATTR;
       return(error);
   }
   
   int
   coda_ioctl(void *v)
   {
   /* true args */
       struct vop_ioctl_args *ap = v;
       struct vnode *vp = ap->a_vp;
       int com = ap->a_command;
       void *data = ap->a_data;
       int flag = ap->a_fflag;
       kauth_cred_t cred = ap->a_cred;
   /* locals */
       int error;
       struct vnode *tvp;
       struct nameidata ndp;
       struct PioctlData *iap = (struct PioctlData *)data;
   
       MARK_ENTRY(CODA_IOCTL_STATS);
   
       CODADEBUG(CODA_IOCTL, myprintf(("in coda_ioctl on %s\n", iap->path));)
   
       /* Don't check for operation on a dying object, for ctlvp it
          shouldn't matter */
   
       /* Must be control object to succeed. */
       if (!IS_CTL_VP(vp)) {
           MARK_INT_FAIL(CODA_IOCTL_STATS);
           CODADEBUG(CODA_IOCTL, myprintf(("coda_ioctl error: vp != ctlvp"));)
               return (EOPNOTSUPP);
       }
       /* Look up the pathname. */
   
       /* Should we use the name cache here? It would get it from
          lookupname sooner or later anyway, right? */
   
       NDINIT(&ndp, LOOKUP, (iap->follow ? FOLLOW : NOFOLLOW), UIO_USERSPACE,
           iap->path);
       error = namei(&ndp);
       tvp = ndp.ni_vp;
   
       if (error) {
           MARK_INT_FAIL(CODA_IOCTL_STATS);
           CODADEBUG(CODA_IOCTL, myprintf(("coda_ioctl error: lookup returns %d\n",
                                      error));)
           return(error);
       }
   
       /*
        * Make sure this is a coda style cnode, but it may be a
        * different vfsp
        */
       /* XXX: this totally violates the comment about vtagtype in vnode.h */
       if (tvp->v_tag != VT_CODA) {
           vrele(tvp);
           MARK_INT_FAIL(CODA_IOCTL_STATS);
           CODADEBUG(CODA_IOCTL,
                    myprintf(("coda_ioctl error: %s not a coda object\n",
                           iap->path));)
           return(EINVAL);
       }
   
       if (iap->vi.in_size > VC_MAXDATASIZE || iap->vi.out_size > VC_MAXDATASIZE) {
           vrele(tvp);
           return(EINVAL);
       }
       error = venus_ioctl(vtomi(tvp), &((VTOC(tvp))->c_fid), com, flag, data,
           cred, curlwp);
   
       if (error)
           MARK_INT_FAIL(CODA_IOCTL_STATS);
       else
           CODADEBUG(CODA_IOCTL, myprintf(("Ioctl returns %d \n", error)); )
   
       vrele(tvp);
       return(error);
   }
   
   /*
    * To reduce the cost of a user-level venus;we cache attributes in
    * the kernel.  Each cnode has storage allocated for an attribute. If
    * c_vattr is valid, return a reference to it. Otherwise, get the
    * attributes from venus and store them in the cnode.  There is some
    * question if this method is a security leak. But I think that in
    * order to make this call, the user must have done a lookup and
    * opened the file, and therefore should already have access.
    */
   int
   coda_getattr(void *v)
   {
   /* true args */
       struct vop_getattr_args *ap = v;
       struct vnode *vp = ap->a_vp;
       struct cnode *cp = VTOC(vp);
       struct vattr *vap = ap->a_vap;
       kauth_cred_t cred = ap->a_cred;
   /* locals */
       int error;
   
       MARK_ENTRY(CODA_GETATTR_STATS);
   
       /* Check for getattr of control object. */
       if (IS_CTL_VP(vp)) {
           MARK_INT_FAIL(CODA_GETATTR_STATS);
           return(ENOENT);
       }
   
       /* Check to see if the attributes have already been cached */
       if (VALID_VATTR(cp)) {
           CODADEBUG(CODA_GETATTR, { myprintf(("attr cache hit: %s\n",
                                           coda_f2s(&cp->c_fid)));});
           CODADEBUG(CODA_GETATTR, if (!(codadebug & ~CODA_GETATTR))
                    print_vattr(&cp->c_vattr); );
   
           *vap = cp->c_vattr;
           MARK_INT_SAT(CODA_GETATTR_STATS);
           return(0);
       }
   
       error = venus_getattr(vtomi(vp), &cp->c_fid, cred, curlwp, vap);
   
       if (!error) {
           CODADEBUG(CODA_GETATTR, myprintf(("getattr miss %s: result %d\n",
                                        coda_f2s(&cp->c_fid), error)); )
   
           CODADEBUG(CODA_GETATTR, if (!(codadebug & ~CODA_GETATTR))
                    print_vattr(vap);      );
   
           /* If not open for write, store attributes in cnode */
           if ((cp->c_owrite == 0) && (coda_attr_cache)) {
               cp->c_vattr = *vap;
               cp->c_flags |= C_VATTR;
           }
   
       }
       return(error);
   }
   
   int
   coda_setattr(void *v)
   {
   /* true args */
       struct vop_setattr_args *ap = v;
       struct vnode *vp = ap->a_vp;
       struct cnode *cp = VTOC(vp);
       struct vattr *vap = ap->a_vap;
       kauth_cred_t cred = ap->a_cred;
   /* locals */
       int error;
   
       MARK_ENTRY(CODA_SETATTR_STATS);
   
       /* Check for setattr of control object. */
       if (IS_CTL_VP(vp)) {
           MARK_INT_FAIL(CODA_SETATTR_STATS);
           return(ENOENT);
       }
   
       if (codadebug & CODADBGMSK(CODA_SETATTR)) {
           print_vattr(vap);
       }
       error = venus_setattr(vtomi(vp), &cp->c_fid, vap, cred, curlwp);
   
       if (!error)
           cp->c_flags &= ~C_VATTR;
   
       CODADEBUG(CODA_SETATTR,     myprintf(("setattr %d\n", error)); )
       return(error);
   }
   
   int
   coda_access(void *v)
   {
   /* true args */
       struct vop_access_args *ap = v;
       struct vnode *vp = ap->a_vp;
       struct cnode *cp = VTOC(vp);
       int mode = ap->a_mode;
       kauth_cred_t cred = ap->a_cred;
   /* locals */
       int error;
   
       MARK_ENTRY(CODA_ACCESS_STATS);
   
       /* Check for access of control object.  Only read access is
          allowed on it. */
       if (IS_CTL_VP(vp)) {
           /* bogus hack - all will be marked as successes */
           MARK_INT_SAT(CODA_ACCESS_STATS);
           return(((mode & VREAD) && !(mode & (VWRITE | VEXEC)))
                  ? 0 : EACCES);
       }
   
       /*
        * if the file is a directory, and we are checking exec (eg lookup)
        * access, and the file is in the namecache, then the user must have
        * lookup access to it.
        */
       if (coda_access_cache) {
           if ((vp->v_type == VDIR) && (mode & VEXEC)) {
               if (coda_nc_lookup(cp, ".", 1, cred)) {
                   MARK_INT_SAT(CODA_ACCESS_STATS);
                   return(0);                     /* it was in the cache */
               }
           }
       }
   
       error = venus_access(vtomi(vp), &cp->c_fid, mode, cred, curlwp);
   
       return(error);
   }
   
   /*
    * CODA abort op, called after namei() when a CREATE/DELETE isn't actually
    * done. If a buffer has been saved in anticipation of a coda_create or
    * a coda_remove, delete it.
    */
   /* ARGSUSED */
   int
   coda_abortop(void *v)
   {
   /* true args */
       struct vop_abortop_args /* {
           struct vnode *a_dvp;
           struct componentname *a_cnp;
       } */ *ap = v;
   /* upcall decl */
   /* locals */
   
       if ((ap->a_cnp->cn_flags & (HASBUF | SAVESTART)) == HASBUF)
           PNBUF_PUT(ap->a_cnp->cn_pnbuf);
       return (0);
   }
   
   int
   coda_readlink(void *v)
   {
   /* true args */
       struct vop_readlink_args *ap = v;
       struct vnode *vp = ap->a_vp;
       struct cnode *cp = VTOC(vp);
       struct uio *uiop = ap->a_uio;
       kauth_cred_t cred = ap->a_cred;
   /* locals */
       struct lwp *l = curlwp;
       int error;
       char *str;
       int len;
   
       MARK_ENTRY(CODA_READLINK_STATS);
   
       /* Check for readlink of control object. */
       if (IS_CTL_VP(vp)) {
           MARK_INT_FAIL(CODA_READLINK_STATS);
           return(ENOENT);
       }
   
       if ((coda_symlink_cache) && (VALID_SYMLINK(cp))) { /* symlink was cached */
           uiop->uio_rw = UIO_READ;
           error = uiomove(cp->c_symlink, (int)cp->c_symlen, uiop);
           if (error)
               MARK_INT_FAIL(CODA_READLINK_STATS);
           else
               MARK_INT_SAT(CODA_READLINK_STATS);
           return(error);
       }
   
       error = venus_readlink(vtomi(vp), &cp->c_fid, cred, l, &str, &len);
   
       if (!error) {
           uiop->uio_rw = UIO_READ;
           error = uiomove(str, len, uiop);
   
           if (coda_symlink_cache) {
               cp->c_symlink = str;
               cp->c_symlen = len;
               cp->c_flags |= C_SYMLINK;
           } else
               CODA_FREE(str, len);
       }
   
       CODADEBUG(CODA_READLINK, myprintf(("in readlink result %d\n",error));)
       return(error);
   }
   
   int
   coda_fsync(void *v)
   {
   /* true args */
       struct vop_fsync_args *ap = v;
       struct vnode *vp = ap->a_vp;
       struct cnode *cp = VTOC(vp);
       kauth_cred_t cred = ap->a_cred;
   /* locals */
       struct vnode *convp = cp->c_ovp;
       int error;
   
       MARK_ENTRY(CODA_FSYNC_STATS);
   
       /* Check for fsync on an unmounting object */
       /* The NetBSD kernel, in it's infinite wisdom, can try to fsync
        * after an unmount has been initiated.  This is a Bad Thing,
        * which we have to avoid.  Not a legitimate failure for stats.
        */
       if (IS_UNMOUNTING(cp)) {
           return(ENODEV);
       }
   
       /* Check for fsync of control object. */
       if (IS_CTL_VP(vp)) {
           MARK_INT_SAT(CODA_FSYNC_STATS);
           return(0);
       }
   
       if (convp)
           VOP_FSYNC(convp, cred, MNT_WAIT, 0, 0);
   
       /*
        * We can expect fsync on any vnode at all if venus is pruging it.
        * Venus can't very well answer the fsync request, now can it?
        * Hopefully, it won't have to, because hopefully, venus preserves
        * the (possibly untrue) invariant that it never purges an open
        * vnode.  Hopefully.
        */
       if (cp->c_flags & C_PURGING) {
           return(0);
       }
   
       error = venus_fsync(vtomi(vp), &cp->c_fid, cred, curlwp);
   
       CODADEBUG(CODA_FSYNC, myprintf(("in fsync result %d\n",error)); );
       return(error);
   }
   
   /*
    * vp is locked on entry, and we must unlock it.
    * XXX This routine is suspect and probably needs rewriting.
    */
   int
   coda_inactive(void *v)
   {
   /* true args */
       struct vop_inactive_args *ap = v;
       struct vnode *vp = ap->a_vp;
       struct cnode *cp = VTOC(vp);
       kauth_cred_t cred __unused = NULL;
   
       /* We don't need to send inactive to venus - DCS */
       MARK_ENTRY(CODA_INACTIVE_STATS);
   
       if (IS_CTL_VP(vp)) {
           MARK_INT_SAT(CODA_INACTIVE_STATS);
           return 0;
       }
   
       CODADEBUG(CODA_INACTIVE, myprintf(("in inactive, %s, vfsp %p\n",
                                     coda_f2s(&cp->c_fid), vp->v_mount));)
   
       /* If an array has been allocated to hold the symlink, deallocate it */
       if ((coda_symlink_cache) && (VALID_SYMLINK(cp))) {
           if (cp->c_symlink == NULL)
               panic("coda_inactive: null symlink pointer in cnode");
   
           CODA_FREE(cp->c_symlink, cp->c_symlen);
           cp->c_flags &= ~C_SYMLINK;
           cp->c_symlen = 0;
       }
   
       /* Remove it from the table so it can't be found. */
       coda_unsave(cp);
       if (vp->v_mount->mnt_data == NULL) {
           myprintf(("Help! vfsp->vfs_data was NULL, but vnode %p wasn't dying\n", vp));
           panic("badness in coda_inactive");
       }
   
       if (IS_UNMOUNTING(cp)) {
           /* XXX Do we need to VOP_CLOSE container vnodes? */
           if (vp->v_usecount > 0)
               printf("coda_inactive: IS_UNMOUNTING %p usecount %d\n",
                      vp, vp->v_usecount);
           if (cp->c_ovp != NULL)
               printf("coda_inactive: %p ovp != NULL\n", vp);
           VOP_UNLOCK(vp, 0);
       } else {
           /* Sanity checks that perhaps should be panic. */
           if (vp->v_usecount) {
               printf("coda_inactive: %p usecount %d\n", vp, vp->v_usecount);
           }
           if (cp->c_ovp != NULL) {
               printf("coda_inactive: %p ovp != NULL\n", vp);
           }
           VOP_UNLOCK(vp, 0);
           *ap->a_recycle = true;
       }
   
       MARK_INT_SAT(CODA_INACTIVE_STATS);
       return(0);
   }
   
   /*
    * Coda does not use the normal namecache, but a private version.
    * Consider how to use the standard facility instead.
    */
   int
   coda_lookup(void *v)
   {
   /* true args */
       struct vop_lookup_args *ap = v;
       /* (locked) vnode of dir in which to do lookup */
       struct vnode *dvp = ap->a_dvp;
       struct cnode *dcp = VTOC(dvp);
       /* output variable for result */
       struct vnode **vpp = ap->a_vpp;
       /* name to lookup */
       struct componentname *cnp = ap->a_cnp;
       kauth_cred_t cred = cnp->cn_cred;
       struct lwp *l = curlwp;
   /* locals */
       struct cnode *cp;
       const char *nm = cnp->cn_nameptr;
       int len = cnp->cn_namelen;
       int flags = cnp->cn_flags;
       int isdot;
       CodaFid VFid;
       int vtype;
       int error = 0;
   
       MARK_ENTRY(CODA_LOOKUP_STATS);
   
       CODADEBUG(CODA_LOOKUP, myprintf(("lookup: %s in %s\n",
                                      nm, coda_f2s(&dcp->c_fid))););
   
       /*
        * XXX componentname flags in MODMASK are not handled at all
        */
   
       /*
        * The overall strategy is to switch on the lookup type and get a
        * result vnode that is vref'd but not locked.  Then, the code at
        * exit: switches on ., .., and regular lookups and does the right
        * locking.
        */
   
       /* Check for lookup of control object. */
       if (IS_CTL_NAME(dvp, nm, len)) {
           *vpp = coda_ctlvp;
           vref(*vpp);
           MARK_INT_SAT(CODA_LOOKUP_STATS);
           goto exit;
       }
   
       /* Avoid trying to hand venus an unreasonably long name. */
       if (len+1 > CODA_MAXNAMLEN) {
           MARK_INT_FAIL(CODA_LOOKUP_STATS);
           CODADEBUG(CODA_LOOKUP, myprintf(("name too long: lookup, %s (%s)\n",
                                       coda_f2s(&dcp->c_fid), nm)););
           *vpp = (struct vnode *)0;
           error = EINVAL;
           goto exit;
       }
   
       /*
        * XXX Check for DOT lookups, and short circuit all the caches,
        * just doing an extra vref.  (venus guarantees that lookup of
        * . returns self.)
        */
       isdot = (len == 1 && nm[0] == '.');
   
       /*
        * Try to resolve the lookup in the minicache.  If that fails, ask
        * venus to do the lookup.  XXX The interaction between vnode
        * locking and any locking that coda does is not clear.
        */
       cp = coda_nc_lookup(dcp, nm, len, cred);
       if (cp) {
           *vpp = CTOV(cp);
           vref(*vpp);
           CODADEBUG(CODA_LOOKUP,
                    myprintf(("lookup result %d vpp %p\n",error,*vpp));)
       } else {
           /* The name wasn't cached, so ask Venus. */
           error = venus_lookup(vtomi(dvp), &dcp->c_fid, nm, len, cred, l, &VFid, &vtype);
   
           if (error) {
               MARK_INT_FAIL(CODA_LOOKUP_STATS);
               CODADEBUG(CODA_LOOKUP, myprintf(("lookup error on %s (%s)%d\n",
                                           coda_f2s(&dcp->c_fid), nm, error));)
               *vpp = (struct vnode *)0;
           } else {
               MARK_INT_SAT(CODA_LOOKUP_STATS);
               CODADEBUG(CODA_LOOKUP,
                        myprintf(("lookup: %s type %o result %d\n",
                               coda_f2s(&VFid), vtype, error)); )
   
               cp = make_coda_node(&VFid, dvp->v_mount, vtype);
               *vpp = CTOV(cp);
               /* vpp is now vrefed. */
   
               /*
                * Unless this vnode is marked CODA_NOCACHE, enter it into
                * the coda name cache to avoid a future venus round-trip.
                * XXX Interaction with componentname NOCACHE is unclear.
                */
               if (!(vtype & CODA_NOCACHE))
                   coda_nc_enter(VTOC(dvp), nm, len, cred, VTOC(*vpp));
           }
       }
   
    exit:
       /*
        * If we are creating, and this was the last name to be looked up,
        * and the error was ENOENT, then make the leaf NULL and return
        * success.
        * XXX Check against new lookup rules.
        */
       if (((cnp->cn_nameiop == CREATE) || (cnp->cn_nameiop == RENAME))
           && (cnp->cn_flags & ISLASTCN)
           && (error == ENOENT))
      {
          error = EJUSTRETURN;
          cnp->cn_flags |= SAVENAME;
          *ap->a_vpp = NULL;
      }
  
      /*
       * If we are removing, and we are at the last element, and we
       * found it, then we need to keep the name around so that the
       * removal will go ahead as planned.
       * XXX Check against new lookup rules.
       */
      if ((cnp->cn_nameiop == DELETE)
          && (cnp->cn_flags & ISLASTCN)
          && !error)
      {
          cnp->cn_flags |= SAVENAME;
      }
  
      /*
       * If the lookup succeeded, we must generally lock the returned
       * vnode.  This could be a ., .., or normal lookup.  See
       * vnodeops(9) for the details.
       */
      /*
       * XXX LK_RETRY is likely incorrect.  Handle vn_lock failure
       * somehow, and remove LK_RETRY.
       */
      if (!error || (error == EJUSTRETURN)) {
          /* Lookup has a value and it isn't "."? */
          if (*ap->a_vpp && (*ap->a_vpp != dvp)) {
              if (flags & ISDOTDOT)
                  /* ..: unlock parent */
                  VOP_UNLOCK(dvp, 0);
              /* all but .: lock child */
              vn_lock(*ap->a_vpp, LK_EXCLUSIVE | LK_RETRY);
              if (flags & ISDOTDOT)
                  /* ..: relock parent */
                  vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY);
          }
          /* else .: leave dvp locked */
      } else {
          /* The lookup failed, so return NULL.  Leave dvp locked. */
          *ap->a_vpp = NULL;
      }
      return(error);
  }
  
  /*ARGSUSED*/
  int
  coda_create(void *v)
  {
  /* true args */
      struct vop_create_args *ap = v;
      struct vnode *dvp = ap->a_dvp;
      struct cnode *dcp = VTOC(dvp);
      struct vattr *va = ap->a_vap;
      int exclusive = 1;
      int mode = ap->a_vap->va_mode;
      struct vnode **vpp = ap->a_vpp;
      struct componentname  *cnp = ap->a_cnp;
      kauth_cred_t cred = cnp->cn_cred;
      struct lwp *l = curlwp;
  /* locals */
      int error;
      struct cnode *cp;
      const char *nm = cnp->cn_nameptr;
      int len = cnp->cn_namelen;
      CodaFid VFid;
      struct vattr attr;
  
      MARK_ENTRY(CODA_CREATE_STATS);
  
      /* All creates are exclusive XXX */
      /* I'm assuming the 'mode' argument is the file mode bits XXX */
  
      /* Check for create of control object. */
      if (IS_CTL_NAME(dvp, nm, len)) {
          *vpp = (struct vnode *)0;
          MARK_INT_FAIL(CODA_CREATE_STATS);
          return(EACCES);
      }
  
      error = venus_create(vtomi(dvp), &dcp->c_fid, nm, len, exclusive, mode, va, cred, l, &VFid, &attr);
  
      if (!error) {
  
          /*
           * XXX Violation of venus/kernel invariants is a difficult case,
           * but venus should not be able to cause a panic.
           */
          /* If this is an exclusive create, panic if the file already exists. */
          /* Venus should have detected the file and reported EEXIST. */
  
          if ((exclusive == 1) &&
              (coda_find(&VFid) != NULL))
              panic("cnode existed for newly created file!");
  
          cp = make_coda_node(&VFid, dvp->v_mount, attr.va_type);
          *vpp = CTOV(cp);
  
          /* XXX vnodeops doesn't say this argument can be changed. */
          /* Update va to reflect the new attributes. */
          (*va) = attr;
  
          /* Update the attribute cache and mark it as valid */
          if (coda_attr_cache) {
              VTOC(*vpp)->c_vattr = attr;
              VTOC(*vpp)->c_flags |= C_VATTR;
          }
  
          /* Invalidate parent's attr cache (modification time has changed). */
          VTOC(dvp)->c_flags &= ~C_VATTR;
  
          /* enter the new vnode in the Name Cache */
          coda_nc_enter(VTOC(dvp), nm, len, cred, VTOC(*vpp));
  
          CODADEBUG(CODA_CREATE,
                   myprintf(("create: %s, result %d\n",
                          coda_f2s(&VFid), error)); )
      } else {
          *vpp = (struct vnode *)0;
          CODADEBUG(CODA_CREATE, myprintf(("create error %d\n", error));)
      }
  
      /*
       * vnodeops(9) says that we must unlock the parent and lock the child.
       * XXX Should we lock the child first?
       */
      vput(dvp);
      if (!error) {
          if ((cnp->cn_flags & LOCKLEAF) == 0) {
              /* This should not happen; flags are for lookup only. */
              printf("coda_create: LOCKLEAF not set!\n");
          }
  
          if ((error = vn_lock(*ap->a_vpp, LK_EXCLUSIVE))) {
              /* XXX Perhaps avoid this panic. */
              panic("coda_create: couldn't lock child");
          }
      }
  
      /* Per vnodeops(9), free name except on success and SAVESTART. */
      if (error || (cnp->cn_flags & SAVESTART) == 0) {
          PNBUF_PUT(cnp->cn_pnbuf);
      }
      return(error);
  }
  
  int
  coda_remove(void *v)
  {
  /* true args */
      struct vop_remove_args *ap = v;
      struct vnode *dvp = ap->a_dvp;
      struct cnode *cp = VTOC(dvp);
      struct vnode *vp = ap->a_vp;
      struct componentname  *cnp = ap->a_cnp;
      kauth_cred_t cred = cnp->cn_cred;
      struct lwp *l = curlwp;
  /* locals */
      int error;
      const char *nm = cnp->cn_nameptr;
      int len = cnp->cn_namelen;
      struct cnode *tp;
  
      MARK_ENTRY(CODA_REMOVE_STATS);
  
      CODADEBUG(CODA_REMOVE, myprintf(("remove: %s in %s\n",
                                     nm, coda_f2s(&cp->c_fid))););
  
      /* Remove the file's entry from the CODA Name Cache */
      /* We're being conservative here, it might be that this person
       * doesn't really have sufficient access to delete the file
       * but we feel zapping the entry won't really hurt anyone -- dcs
       */
      /* I'm gonna go out on a limb here. If a file and a hardlink to it
       * exist, and one is removed, the link count on the other will be
       * off by 1. We could either invalidate the attrs if cached, or
       * fix them. I'll try to fix them. DCS 11/8/94
       */
      tp = coda_nc_lookup(VTOC(dvp), nm, len, cred);
      if (tp) {
          if (VALID_VATTR(tp)) {  /* If attrs are cached */
              if (tp->c_vattr.va_nlink > 1) {     /* If it's a hard link */
                  tp->c_vattr.va_nlink--;
              }
          }
  
          coda_nc_zapfile(VTOC(dvp), nm, len);
          /* No need to flush it if it doesn't exist! */
      }
      /* Invalidate the parent's attr cache, the modification time has changed */
      VTOC(dvp)->c_flags &= ~C_VATTR;
  
      /* Check for remove of control object. */
      if (IS_CTL_NAME(dvp, nm, len)) {
          MARK_INT_FAIL(CODA_REMOVE_STATS);
          return(ENOENT);
      }
  
      error = venus_remove(vtomi(dvp), &cp->c_fid, nm, len, cred, l);
  
      CODADEBUG(CODA_REMOVE, myprintf(("in remove result %d\n",error)); )
  
      /*
       * Unlock parent and child (avoiding double if ".").
       */
      if (dvp == vp) {
          vrele(vp);
      } else {
          vput(vp);
      }
      vput(dvp);
  
      return(error);
  }
  
  /*
   * dvp is the directory where the link is to go, and is locked.
   * vp is the object to be linked to, and is unlocked.
   * At exit, we must unlock dvp, and vput dvp.
   */
  int
  coda_link(void *v)
  {
  /* true args */
      struct vop_link_args *ap = v;
      struct vnode *vp = ap->a_vp;
      struct cnode *cp = VTOC(vp);
      struct vnode *dvp = ap->a_dvp;
      struct cnode *dcp = VTOC(dvp);
      struct componentname *cnp = ap->a_cnp;
      kauth_cred_t cred = cnp->cn_cred;
      struct lwp *l = curlwp;
  /* locals */
      int error;
      const char *nm = cnp->cn_nameptr;
      int len = cnp->cn_namelen;
  
      MARK_ENTRY(CODA_LINK_STATS);
  
      if (codadebug & CODADBGMSK(CODA_LINK)) {
  
          myprintf(("nb_link:   vp fid: %s\n",
                    coda_f2s(&cp->c_fid)));
          myprintf(("nb_link: dvp fid: %s)\n",
                    coda_f2s(&dcp->c_fid)));
  
      }
      if (codadebug & CODADBGMSK(CODA_LINK)) {
          myprintf(("link:   vp fid: %s\n",
                    coda_f2s(&cp->c_fid)));
          myprintf(("link: dvp fid: %s\n",
                    coda_f2s(&dcp->c_fid)));
  
      }
  
      /* Check for link to/from control object. */
      if (IS_CTL_NAME(dvp, nm, len) || IS_CTL_VP(vp)) {
          MARK_INT_FAIL(CODA_LINK_STATS);
          return(EACCES);
      }
  
      /* If linking . to a name, error out earlier. */
      if (vp == dvp) {
          printf("coda_link vp==dvp\n");
          error = EISDIR;
          goto exit;
      }
  
      /* XXX Why does venus_link need the vnode to be locked?*/
      if ((error = vn_lock(vp, LK_EXCLUSIVE)) != 0) {
          printf("coda_link: couldn't lock vnode %p\n", vp);
          error = EFAULT;         /* XXX better value */
          goto exit;
      }
      error = venus_link(vtomi(vp), &cp->c_fid, &dcp->c_fid, nm, len, cred, l);
      VOP_UNLOCK(vp, 0);
  
      /* Invalidate parent's attr cache (the modification time has changed). */
      VTOC(dvp)->c_flags &= ~C_VATTR;
      /* Invalidate child's attr cache (XXX why). */
      VTOC(vp)->c_flags &= ~C_VATTR;
  
      CODADEBUG(CODA_LINK,        myprintf(("in link result %d\n",error)); )
  
  exit:
      vput(dvp);
      return(error);
  }
  
  int
  coda_rename(void *v)
  {
  /* true args */
      struct vop_rename_args *ap = v;
      struct vnode *odvp = ap->a_fdvp;
      struct cnode *odcp = VTOC(odvp);
      struct componentname  *fcnp = ap->a_fcnp;
      struct vnode *ndvp = ap->a_tdvp;
      struct cnode *ndcp = VTOC(ndvp);
      struct componentname  *tcnp = ap->a_tcnp;
      kauth_cred_t cred = fcnp->cn_cred;
      struct lwp *l = curlwp;
  /* true args */
      int error;
      const char *fnm = fcnp->cn_nameptr;
      int flen = fcnp->cn_namelen;
      const char *tnm = tcnp->cn_nameptr;
      int tlen = tcnp->cn_namelen;
  
      MARK_ENTRY(CODA_RENAME_STATS);
  
      /* Hmmm.  The vnodes are already looked up.  Perhaps they are locked?
         This could be Bad. XXX */
  #ifdef OLD_DIAGNOSTIC
      if ((fcnp->cn_cred != tcnp->cn_cred)
          || (fcnp->cn_lwp != tcnp->cn_lwp))
      {
          panic("coda_rename: component names don't agree");
      }
  #endif
  
      /* Check for rename involving control object. */
      if (IS_CTL_NAME(odvp, fnm, flen) || IS_CTL_NAME(ndvp, tnm, tlen)) {
          MARK_INT_FAIL(CODA_RENAME_STATS);
          return(EACCES);
      }
  
      /* Problem with moving directories -- need to flush entry for .. */
      if (odvp != ndvp) {
          struct cnode *ovcp = coda_nc_lookup(VTOC(odvp), fnm, flen, cred);
          if (ovcp) {
              struct vnode *ovp = CTOV(ovcp);
              if ((ovp) &&
                  (ovp->v_type == VDIR)) /* If it's a directory */
                  coda_nc_zapfile(VTOC(ovp),"..", 2);
          }
      }
  
      /* Remove the entries for both source and target files */
      coda_nc_zapfile(VTOC(odvp), fnm, flen);
      coda_nc_zapfile(VTOC(ndvp), tnm, tlen);
  
      /* Invalidate the parent's attr cache, the modification time has changed */
      VTOC(odvp)->c_flags &= ~C_VATTR;
      VTOC(ndvp)->c_flags &= ~C_VATTR;
  
      if (flen+1 > CODA_MAXNAMLEN) {
          MARK_INT_FAIL(CODA_RENAME_STATS);
          error = EINVAL;
          goto exit;
      }
  
      if (tlen+1 > CODA_MAXNAMLEN) {
          MARK_INT_FAIL(CODA_RENAME_STATS);
          error = EINVAL;
          goto exit;
      }
  
      error = venus_rename(vtomi(odvp), &odcp->c_fid, &ndcp->c_fid, fnm, flen, tnm, tlen, cred, l);
  
   exit:
      CODADEBUG(CODA_RENAME, myprintf(("in rename result %d\n",error));)
      /* XXX - do we need to call cache pureg on the moved vnode? */
      cache_purge(ap->a_fvp);
  
      /* It seems to be incumbent on us to drop locks on all four vnodes */
      /* From-vnodes are not locked, only ref'd.  To-vnodes are locked. */
  
      vrele(ap->a_fvp);
      vrele(odvp);
  
      if (ap->a_tvp) {
          if (ap->a_tvp == ndvp) {
              vrele(ap->a_tvp);
          } else {
              vput(ap->a_tvp);
          }
      }
  
      vput(ndvp);
      return(error);
  }
  
  int
  coda_mkdir(void *v)
  {
  /* true args */
      struct vop_mkdir_args *ap = v;
      struct vnode *dvp = ap->a_dvp;
      struct cnode *dcp = VTOC(dvp);
      struct componentname  *cnp = ap->a_cnp;
      struct vattr *va = ap->a_vap;
      struct vnode **vpp = ap->a_vpp;
      kauth_cred_t cred = cnp->cn_cred;
      struct lwp *l = curlwp;
  /* locals */
      int error;
      const char *nm = cnp->cn_nameptr;
      int len = cnp->cn_namelen;
      struct cnode *cp;
      CodaFid VFid;
      struct vattr ova;
  
      MARK_ENTRY(CODA_MKDIR_STATS);
  
      /* Check for mkdir of target object. */
      if (IS_CTL_NAME(dvp, nm, len)) {
          *vpp = (struct vnode *)0;
          MARK_INT_FAIL(CODA_MKDIR_STATS);
          return(EACCES);
      }
  
      if (len+1 > CODA_MAXNAMLEN) {
          *vpp = (struct vnode *)0;
          MARK_INT_FAIL(CODA_MKDIR_STATS);
          return(EACCES);
      }
  
      error = venus_mkdir(vtomi(dvp), &dcp->c_fid, nm, len, va, cred, l, &VFid, &ova);
  
      if (!error) {
          if (coda_find(&VFid) != NULL)
              panic("cnode existed for newly created directory!");
  
  
          cp =  make_coda_node(&VFid, dvp->v_mount, va->va_type);
          *vpp = CTOV(cp);
  
          /* enter the new vnode in the Name Cache */
          coda_nc_enter(VTOC(dvp), nm, len, cred, VTOC(*vpp));
  
          /* as a side effect, enter "." and ".." for the directory */
          coda_nc_enter(VTOC(*vpp), ".", 1, cred, VTOC(*vpp));
          coda_nc_enter(VTOC(*vpp), "..", 2, cred, VTOC(dvp));
  
          if (coda_attr_cache) {
              VTOC(*vpp)->c_vattr = ova;          /* update the attr cache */
              VTOC(*vpp)->c_flags |= C_VATTR;     /* Valid attributes in cnode */
          }
  
          /* Invalidate the parent's attr cache, the modification time has changed */
          VTOC(dvp)->c_flags &= ~C_VATTR;
  
          CODADEBUG( CODA_MKDIR, myprintf(("mkdir: %s result %d\n",
                                      coda_f2s(&VFid), error)); )
      } else {
          *vpp = (struct vnode *)0;
          CODADEBUG(CODA_MKDIR, myprintf(("mkdir error %d\n",error));)
      }
  
      /*
       * Currently, all mkdirs explicitly vput their dvp's.
       * It also appears that we *must* lock the vpp, since
       * lockleaf isn't set, but someone down the road is going
       * to try to unlock the new directory.
       */
      vput(dvp);
      if (!error) {
          if ((error = vn_lock(*ap->a_vpp, LK_EXCLUSIVE))) {
              panic("coda_mkdir: couldn't lock child");
          }
      }
  
      /* Per vnodeops(9), free name except on success and SAVESTART. */
      if (error || (cnp->cn_flags & SAVESTART) == 0) {
          PNBUF_PUT(cnp->cn_pnbuf);
      }
      return(error);
  }
  
  int
  coda_rmdir(void *v)
  {
  /* true args */
      struct vop_rmdir_args *ap = v;
      struct vnode *dvp = ap->a_dvp;
      struct cnode *dcp = VTOC(dvp);
      struct vnode *vp = ap->a_vp;
      struct componentname  *cnp = ap->a_cnp;
      kauth_cred_t cred = cnp->cn_cred;
      struct lwp *l = curlwp;
  /* true args */
      int error;
      const char *nm = cnp->cn_nameptr;
      int len = cnp->cn_namelen;
      struct cnode *cp;
  
      MARK_ENTRY(CODA_RMDIR_STATS);
  
      /* Check for rmdir of control object. */
      if (IS_CTL_NAME(dvp, nm, len)) {
          MARK_INT_FAIL(CODA_RMDIR_STATS);
          return(ENOENT);
      }
  
      /* Can't remove . in self. */
      if (dvp == vp) {
          printf("coda_rmdir: dvp == vp\n");
          error = EINVAL;
          goto exit;
      }
  
      /*
       * The caller may not have adequate permissions, and the venus
       * operation may fail, but it doesn't hurt from a correctness
       * viewpoint to invalidate cache entries.
       * XXX Why isn't this done after the venus_rmdir call?
       */
      /* Look up child in name cache (by name, from parent). */
      cp = coda_nc_lookup(dcp, nm, len, cred);
      /* If found, remove all children of the child (., ..). */
      if (cp) coda_nc_zapParentfid(&(cp->c_fid), NOT_DOWNCALL);
  
      /* Remove child's own entry. */
      coda_nc_zapfile(dcp, nm, len);
  
      /* Invalidate parent's attr cache (the modification time has changed). */
      dcp->c_flags &= ~C_VATTR;
  
      error = venus_rmdir(vtomi(dvp), &dcp->c_fid, nm, len, cred, l);
  
      CODADEBUG(CODA_RMDIR, myprintf(("in rmdir result %d\n", error)); )
  
  exit:
      /* vput both vnodes */
      vput(dvp);
      if (dvp == vp) {
          vrele(vp);
      } else {
          vput(vp);
      }
  
      return(error);
  }
  
  int
  coda_symlink(void *v)
  {
  /* true args */
      struct vop_symlink_args *ap = v;
      struct vnode *dvp = ap->a_dvp;
      struct cnode *dcp = VTOC(dvp);
      /* a_vpp is used in place below */
      struct componentname *cnp = ap->a_cnp;
      struct vattr *tva = ap->a_vap;
      char *path = ap->a_target;
      kauth_cred_t cred = cnp->cn_cred;
      struct lwp *l = curlwp;
  /* locals */
      int error;
      u_long saved_cn_flags;
      const char *nm = cnp->cn_nameptr;
      int len = cnp->cn_namelen;
      int plen = strlen(path);
  
      /*
       * Here's the strategy for the moment: perform the symlink, then
       * do a lookup to grab the resulting vnode.  I know this requires
       * two communications with Venus for a new sybolic link, but
       * that's the way the ball bounces.  I don't yet want to change
       * the way the Mach symlink works.  When Mach support is
       * deprecated, we should change symlink so that the common case
       * returns the resultant vnode in a vpp argument.
       */
  
      MARK_ENTRY(CODA_SYMLINK_STATS);
  
      /* Check for symlink of control object. */
      if (IS_CTL_NAME(dvp, nm, len)) {
          MARK_INT_FAIL(CODA_SYMLINK_STATS);
          error = EACCES; 
          goto exit;
      }
  
      if (plen+1 > CODA_MAXPATHLEN) {
          MARK_INT_FAIL(CODA_SYMLINK_STATS);
          error = EINVAL;
          goto exit;
      }
  
      if (len+1 > CODA_MAXNAMLEN) {
          MARK_INT_FAIL(CODA_SYMLINK_STATS);
          error = EINVAL;
          goto exit;
      }
  
      error = venus_symlink(vtomi(dvp), &dcp->c_fid, path, plen, nm, len, tva, cred, l);
  
      /* Invalidate the parent's attr cache (modification time has changed). */
      dcp->c_flags &= ~C_VATTR;
  
      if (!error) {
          /*
           * VOP_SYMLINK is not defined to pay attention to cnp->cn_flags;
           * these are defined only for VOP_LOOKUP.   We desire to reuse
           * cnp for a VOP_LOOKUP operation, and must be sure to not pass
           * stray flags passed to us.  Such stray flags can occur because
           * sys_symlink makes a namei call and then reuses the
           * componentname structure.
           */
          /*
           * XXX Arguably we should create our own componentname structure
           * and not reuse the one that was passed in.
           */
          saved_cn_flags = cnp->cn_flags;
          cnp->cn_flags &= ~(MODMASK | OPMASK);
          cnp->cn_flags |= LOOKUP;
          error = VOP_LOOKUP(dvp, ap->a_vpp, cnp);
          cnp->cn_flags = saved_cn_flags;
          /* Either an error occurs, or ap->a_vpp is locked. */
      }
  
   exit:
      /* unlock and deference parent */
      vput(dvp);
  
      /* Per vnodeops(9), free name except on success and SAVESTART. */
      if (error || (cnp->cn_flags & SAVESTART) == 0) {
          PNBUF_PUT(cnp->cn_pnbuf);
      }
  
      CODADEBUG(CODA_SYMLINK, myprintf(("in symlink result %d\n",error)); )
      return(error);
  }
  
  /*
   * Read directory entries.
   */
  int
  coda_readdir(void *v)
  {
  /* true args */
      struct vop_readdir_args *ap = v;
      struct vnode *vp = ap->a_vp;
      struct cnode *cp = VTOC(vp);
      struct uio *uiop = ap->a_uio;
      kauth_cred_t cred = ap->a_cred;
      int *eofflag = ap->a_eofflag;
      off_t **cookies = ap->a_cookies;
      int *ncookies = ap->a_ncookies;
  /* upcall decl */
  /* locals */
      int error = 0;
  
      MARK_ENTRY(CODA_READDIR_STATS);
  
      CODADEBUG(CODA_READDIR, myprintf(("coda_readdir(%p, %lu, %lld)\n", uiop->uio_iov->iov_base, (unsigned long) uiop->uio_resid, (long long) uiop->uio_offset)); )
  
      /* Check for readdir of control object. */
      if (IS_CTL_VP(vp)) {
          MARK_INT_FAIL(CODA_READDIR_STATS);
          return(ENOENT);
      }
  
      {
          /* Redirect the request to UFS. */
  
          /* If directory is not already open do an "internal open" on it. */
          int opened_internally = 0;
          if (cp->c_ovp == NULL) {
              opened_internally = 1;
              MARK_INT_GEN(CODA_OPEN_STATS);
              error = VOP_OPEN(vp, FREAD, cred);
  #ifdef  CODA_VERBOSE
  printf("coda_readdir: Internally Opening %p\n", vp);
  #endif
              if (error) return(error);
          } else
              vp = cp->c_ovp;
  
          /* Have UFS handle the call. */
          CODADEBUG(CODA_READDIR, myprintf((
                                  "indirect readdir: fid = %s, refcnt = %d\n",
                                  coda_f2s(&cp->c_fid), vp->v_usecount)); )
          error = VOP_READDIR(vp, uiop, cred, eofflag, cookies, ncookies);
          if (error)
              MARK_INT_FAIL(CODA_READDIR_STATS);
          else
              MARK_INT_SAT(CODA_READDIR_STATS);
  
          /* Do an "internal close" if necessary. */
          if (opened_internally) {
              MARK_INT_GEN(CODA_CLOSE_STATS);
              (void)VOP_CLOSE(vp, FREAD, cred);
          }
      }
  
      return(error);
  }
  
  /*
   * Convert from file system blocks to device blocks
   */
  int
  coda_bmap(void *v)
  {
      /* XXX on the global proc */
  /* true args */
      struct vop_bmap_args *ap = v;
      struct vnode *vp __unused = ap->a_vp;       /* file's vnode */
      daddr_t bn __unused = ap->a_bn;     /* fs block number */
      struct vnode **vpp = ap->a_vpp;                     /* RETURN vp of device */
      daddr_t *bnp __unused = ap->a_bnp;  /* RETURN device block number */
      struct lwp *l __unused = curlwp;
  /* upcall decl */
  /* locals */
  
          *vpp = (struct vnode *)0;
          myprintf(("coda_bmap called!\n"));
          return(EINVAL);
  }
  
  /*
   * I don't think the following two things are used anywhere, so I've
   * commented them out
   *
   * struct buf *async_bufhead;
   * int async_daemon_count;
   */
  int
  coda_strategy(void *v)
  {
  /* true args */
      struct vop_strategy_args *ap = v;
      struct buf *bp __unused = ap->a_bp;
      struct lwp *l __unused = curlwp;
  /* upcall decl */
  /* locals */
  
          myprintf(("coda_strategy called!  "));
          return(EINVAL);
  }
  
  int
  coda_reclaim(void *v)
  {
  /* true args */
      struct vop_reclaim_args *ap = v;
      struct vnode *vp = ap->a_vp;
      struct cnode *cp = VTOC(vp);
  /* upcall decl */
  /* locals */
  
  /*
   * Forced unmount/flush will let vnodes with non zero use be destroyed!
   */
      ENTRY;
  
      if (IS_UNMOUNTING(cp)) {
  #ifdef  DEBUG
          if (VTOC(vp)->c_ovp) {
              if (IS_UNMOUNTING(cp))
                  printf("coda_reclaim: c_ovp not void: vp %p, cp %p\n", vp, cp);
          }
  #endif
      } else {
  #ifdef OLD_DIAGNOSTIC
          if (vp->v_usecount != 0)
              print("coda_reclaim: pushing active %p\n", vp);
          if (VTOC(vp)->c_ovp) {
              panic("coda_reclaim: c_ovp not void");
          }
  #endif
      }
      cache_purge(vp);
      coda_free(VTOC(vp));
      SET_VTOC(vp) = NULL;
      return (0);
  }
  
  int
  coda_lock(void *v)
  {
  /* true args */
      struct vop_lock_args *ap = v;
      struct vnode *vp = ap->a_vp;
      struct cnode *cp = VTOC(vp);
      int flags  = ap->a_flags;
  /* upcall decl */
  /* locals */
  
      ENTRY;
  
      if (coda_lockdebug) {
          myprintf(("Attempting lock on %s\n",
                    coda_f2s(&cp->c_fid)));
      }
  
      if ((flags & LK_INTERLOCK) != 0) {
          mutex_exit(&vp->v_interlock);
          flags &= ~LK_INTERLOCK;
      }
  
      return (vlockmgr(&vp->v_lock, flags));
  }
  
  int
  coda_unlock(void *v)
  {
  /* true args */
      struct vop_unlock_args *ap = v;
      struct vnode *vp = ap->a_vp;
      struct cnode *cp = VTOC(vp);
  /* upcall decl */
  /* locals */
  
      ENTRY;
      if (coda_lockdebug) {
          myprintf(("Attempting unlock on %s\n",
                    coda_f2s(&cp->c_fid)));
      }
  
      return (vlockmgr(&vp->v_lock, ap->a_flags | LK_RELEASE));
  }
  
  int
  coda_islocked(void *v)
  {
  /* true args */
      struct vop_islocked_args *ap = v;
      ENTRY;
  
      return (vlockstatus(&ap->a_vp->v_lock));
  }
  
  /*
   * Given a device and inode, obtain a locked vnode.  One reference is
   * obtained and passed back to the caller.
   */
  int
  coda_grab_vnode(dev_t dev, ino_t ino, struct vnode **vpp)
  {
      int           error;
      struct mount *mp;
  
      /* Obtain mount point structure from device. */
      if (!(mp = devtomp(dev))) {
          myprintf(("coda_grab_vnode: devtomp(%d) returns NULL\n", dev));
          return(ENXIO);
      }
  
      /*
       * Obtain vnode from mount point and inode.
       * XXX VFS_VGET does not clearly define locked/referenced state of
       * returned vnode.
       */
      error = VFS_VGET(mp, ino, vpp);
      if (error) {
          myprintf(("coda_grab_vnode: iget/vget(%d, %llu) returns %p, err %d\n",
                    dev, (unsigned long long)ino, *vpp, error));
          return(ENOENT);
      }
      return(0);
  }
  
  void
  print_vattr(struct vattr *attr)
  {
      const char *typestr;
  
      switch (attr->va_type) {
      case VNON:
          typestr = "VNON";
          break;
      case VREG:
          typestr = "VREG";
          break;
      case VDIR:
          typestr = "VDIR";
          break;
      case VBLK:
          typestr = "VBLK";
          break;
      case VCHR:
          typestr = "VCHR";
          break;
      case VLNK:
          typestr = "VLNK";
          break;
      case VSOCK:
          typestr = "VSCK";
          break;
      case VFIFO:
          typestr = "VFFO";
          break;
      case VBAD:
          typestr = "VBAD";
          break;
      default:
          typestr = "????";
          break;
      }
  
  
      myprintf(("attr: type %s mode %d uid %d gid %d fsid %d rdev %d\n",
                typestr, (int)attr->va_mode, (int)attr->va_uid,
                (int)attr->va_gid, (int)attr->va_fsid, (int)attr->va_rdev));
  
      myprintf(("      fileid %d nlink %d size %d blocksize %d bytes %d\n",
                (int)attr->va_fileid, (int)attr->va_nlink,
                (int)attr->va_size,
                (int)attr->va_blocksize,(int)attr->va_bytes));
      myprintf(("      gen %ld flags %ld vaflags %d\n",
                attr->va_gen, attr->va_flags, attr->va_vaflags));
      myprintf(("      atime sec %d nsec %d\n",
                (int)attr->va_atime.tv_sec, (int)attr->va_atime.tv_nsec));
      myprintf(("      mtime sec %d nsec %d\n",
                (int)attr->va_mtime.tv_sec, (int)attr->va_mtime.tv_nsec));
      myprintf(("      ctime sec %d nsec %d\n",
                (int)attr->va_ctime.tv_sec, (int)attr->va_ctime.tv_nsec));
  }
  
  /* How to print a ucred */
  void
  print_cred(kauth_cred_t cred)
  {
  
          uint16_t ngroups;
          int i;
  
          myprintf(("ref %d\tuid %d\n", kauth_cred_getrefcnt(cred),
                   kauth_cred_geteuid(cred)));
  
          ngroups = kauth_cred_ngroups(cred);
          for (i=0; i < ngroups; i++)
                  myprintf(("\tgroup %d: (%d)\n", i, kauth_cred_group(cred, i)));
          myprintf(("\n"));
  
  }
  
  /*
   * Return a vnode for the given fid.
   * If no cnode exists for this fid create one and put it
   * in a table hashed by coda_f2i().  If the cnode for
   * this fid is already in the table return it (ref count is
   * incremented by coda_find.  The cnode will be flushed from the
   * table when coda_inactive calls coda_unsave.
   */
  struct cnode *
  make_coda_node(CodaFid *fid, struct mount *vfsp, short type)
  {
      struct cnode *cp;
      int          err;
  
      if ((cp = coda_find(fid)) == NULL) {
          struct vnode *vp;
  
          cp = coda_alloc();
          cp->c_fid = *fid;
  
          err = getnewvnode(VT_CODA, vfsp, coda_vnodeop_p, &vp);
          if (err) {
              panic("coda: getnewvnode returned error %d", err);
          }
          vp->v_data = cp;
          vp->v_type = type;
          cp->c_vnode = vp;
          uvm_vnp_setsize(vp, 0);
          coda_save(cp);
  
      } else {
          vref(CTOV(cp));
      }
  
      return cp;
  }
  
  /*
   * coda_getpages may be called on a vnode which has not been opened,
   * e.g. to fault in pages to execute a program.  In that case, we must
   * open the file to get the container.  The vnode may or may not be
   * locked, and we must leave it in the same state.
   * XXX The protocol requires v_uobj.vmobjlock to be
   * held by caller, but this isn't documented in vnodeops(9) or vnode_if.src.
   */
  int
  coda_getpages(void *v)
  {
          struct vop_getpages_args /* {
                  struct vnode *a_vp;
                  voff_t a_offset;
                  struct vm_page **a_m;
                  int *a_count;
                  int a_centeridx;
                  vm_prot_t a_access_type;
                  int a_advice;
                  int a_flags;
          } */ *ap = v;
          struct vnode *vp = ap->a_vp;
          struct cnode *cp = VTOC(vp);
          struct lwp *l = curlwp;
          kauth_cred_t cred = l->l_cred;
          int error, cerror;
          int waslocked;         /* 1 if vnode lock was held on entry */
          int didopen = 0;        /* 1 if we opened container file */
  
          /*
           * Handle a case that uvm_fault doesn't quite use yet.
           * See layer_vnops.c. for inspiration.
           */
          if (ap->a_flags & PGO_LOCKED) {
                  return EBUSY;
          }
  
          /* Check for control object. */
          if (IS_CTL_VP(vp)) {
                  printf("coda_getpages: control object %p\n", vp);
                  mutex_exit(&vp->v_uobj.vmobjlock);
                  return(EINVAL);
          }
  
          /*
           * XXX It's really not ok to be releasing the lock we get,
           * because we could be overlapping with another call to
           * getpages and drop a lock they are relying on.  We need to
           * figure out whether getpages ever is called holding the
           * lock, and if we should serialize getpages calls by some
           * mechanism.
           */
          waslocked = VOP_ISLOCKED(vp);
  
          /* Drop the vmobject lock. */
          mutex_exit(&vp->v_uobj.vmobjlock);
  
          /* Get container file if not already present. */
          if (cp->c_ovp == NULL) {
                  /*
                   * VOP_OPEN requires a locked vnode.  We must avoid
                   * locking the vnode if it is already locked, and
                   * leave it in the same state on exit.
                   */
                  if (waslocked == 0) {
                          cerror = vn_lock(vp, LK_EXCLUSIVE);
                          if (cerror) {
                                  printf("coda_getpages: can't lock vnode %p\n",
                                         vp);
                                  return cerror;
                          }
  #if 0
                          printf("coda_getpages: locked vnode %p\n", vp);
  #endif
                  }
  
                  /*
                   * Open file (causes upcall to venus).
                   * XXX Perhaps we should not fully open the file, but
                   * simply obtain a container file.
                   */
                  /* XXX Is it ok to do this while holding the simplelock? */
                  cerror = VOP_OPEN(vp, FREAD, cred);
  
                  if (cerror) {
                          printf("coda_getpages: cannot open vnode %p => %d\n",
                                 vp, cerror);
                          if (waslocked == 0)
                                  VOP_UNLOCK(vp, 0);
                          return cerror;
                  }
  
  #if 0
                  printf("coda_getpages: opened vnode %p\n", vp);
  #endif
                  didopen = 1;
          }
          KASSERT(cp->c_ovp != NULL);
  
          /* Munge the arg structure to refer to the container vnode. */
          ap->a_vp = cp->c_ovp;
  
          /* Get the lock on the container vnode, and call getpages on it. */
          mutex_enter(&ap->a_vp->v_uobj.vmobjlock);
          error = VCALL(ap->a_vp, VOFFSET(vop_getpages), ap);
  
          /* If we opened the vnode, we must close it. */
          if (didopen) {
                  /*
                   * VOP_CLOSE requires a locked vnode, but we are still
                   * holding the lock (or riding a caller's lock).
                   */
                  cerror = VOP_CLOSE(vp, FREAD, cred);
                  if (cerror != 0)
                          /* XXX How should we handle this? */
                          printf("coda_getpages: closed vnode %p -> %d\n",
                                 vp, cerror);
  
                  /* If we obtained a lock, drop it. */
                  if (waslocked == 0)
                          VOP_UNLOCK(vp, 0);
          }
  
          return error;
  }
  
  /*
   * The protocol requires v_uobj.vmobjlock to be held by the caller, as
   * documented in vnodeops(9).  XXX vnode_if.src doesn't say this.
   */
  int
  coda_putpages(void *v)
  {
          struct vop_putpages_args /* {
                  struct vnode *a_vp;
                  voff_t a_offlo;
                  voff_t a_offhi;
                  int a_flags;
          } */ *ap = v;
          struct vnode *vp = ap->a_vp;
          struct cnode *cp = VTOC(vp);
          int error;
  
          /* Drop the vmobject lock. */
          mutex_exit(&vp->v_uobj.vmobjlock);
  
          /* Check for control object. */
          if (IS_CTL_VP(vp)) {
                  printf("coda_putpages: control object %p\n", vp);
                  return(EINVAL);
          }
  
          /*
           * If container object is not present, then there are no pages
           * to put; just return without error.  This happens all the
           * time, apparently during discard of a closed vnode (which
           * trivially can't have dirty pages).
           */
          if (cp->c_ovp == NULL)
                  return 0;
  
          /* Munge the arg structure to refer to the container vnode. */
          ap->a_vp = cp->c_ovp;
  
          /* Get the lock on the container vnode, and call putpages on it. */
          mutex_enter(&ap->a_vp->v_uobj.vmobjlock);
          error = VCALL(ap->a_vp, VOFFSET(vop_putpages), ap);
  
          return error;
  }

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