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coda_vnops.c revision 1.79.2.1
      1 /*	$NetBSD: coda_vnops.c,v 1.79.2.1 2011/06/23 14:19:52 cherry Exp $	*/
      2 
      3 /*
      4  *
      5  *             Coda: an Experimental Distributed File System
      6  *                              Release 3.1
      7  *
      8  *           Copyright (c) 1987-1998 Carnegie Mellon University
      9  *                          All Rights Reserved
     10  *
     11  * Permission  to  use, copy, modify and distribute this software and its
     12  * documentation is hereby granted,  provided  that  both  the  copyright
     13  * notice  and  this  permission  notice  appear  in  all  copies  of the
     14  * software, derivative works or  modified  versions,  and  any  portions
     15  * thereof, and that both notices appear in supporting documentation, and
     16  * that credit is given to Carnegie Mellon University  in  all  documents
     17  * and publicity pertaining to direct or indirect use of this code or its
     18  * derivatives.
     19  *
     20  * CODA IS AN EXPERIMENTAL SOFTWARE SYSTEM AND IS  KNOWN  TO  HAVE  BUGS,
     21  * SOME  OF  WHICH MAY HAVE SERIOUS CONSEQUENCES.  CARNEGIE MELLON ALLOWS
     22  * FREE USE OF THIS SOFTWARE IN ITS "AS IS" CONDITION.   CARNEGIE  MELLON
     23  * DISCLAIMS  ANY  LIABILITY  OF  ANY  KIND  FOR  ANY  DAMAGES WHATSOEVER
     24  * RESULTING DIRECTLY OR INDIRECTLY FROM THE USE OF THIS SOFTWARE  OR  OF
     25  * ANY DERIVATIVE WORK.
     26  *
     27  * Carnegie  Mellon  encourages  users  of  this  software  to return any
     28  * improvements or extensions that  they  make,  and  to  grant  Carnegie
     29  * Mellon the rights to redistribute these changes without encumbrance.
     30  *
     31  * 	@(#) coda/coda_vnops.c,v 1.1.1.1 1998/08/29 21:26:46 rvb Exp $
     32  */
     33 
     34 /*
     35  * Mach Operating System
     36  * Copyright (c) 1990 Carnegie-Mellon University
     37  * Copyright (c) 1989 Carnegie-Mellon University
     38  * All rights reserved.  The CMU software License Agreement specifies
     39  * the terms and conditions for use and redistribution.
     40  */
     41 
     42 /*
     43  * This code was written for the Coda file system at Carnegie Mellon
     44  * University.  Contributers include David Steere, James Kistler, and
     45  * M. Satyanarayanan.
     46  */
     47 
     48 #include <sys/cdefs.h>
     49 __KERNEL_RCSID(0, "$NetBSD: coda_vnops.c,v 1.79.2.1 2011/06/23 14:19:52 cherry Exp $");
     50 
     51 #include <sys/param.h>
     52 #include <sys/systm.h>
     53 #include <sys/malloc.h>
     54 #include <sys/errno.h>
     55 #include <sys/acct.h>
     56 #include <sys/file.h>
     57 #include <sys/uio.h>
     58 #include <sys/namei.h>
     59 #include <sys/ioctl.h>
     60 #include <sys/mount.h>
     61 #include <sys/proc.h>
     62 #include <sys/select.h>
     63 #include <sys/vnode.h>
     64 #include <sys/kauth.h>
     65 
     66 #include <miscfs/genfs/genfs.h>
     67 
     68 #include <coda/coda.h>
     69 #include <coda/cnode.h>
     70 #include <coda/coda_vnops.h>
     71 #include <coda/coda_venus.h>
     72 #include <coda/coda_opstats.h>
     73 #include <coda/coda_subr.h>
     74 #include <coda/coda_namecache.h>
     75 #include <coda/coda_pioctl.h>
     76 
     77 /*
     78  * These flags select various performance enhancements.
     79  */
     80 int coda_attr_cache  = 1;       /* Set to cache attributes in the kernel */
     81 int coda_symlink_cache = 1;     /* Set to cache symbolic link information */
     82 int coda_access_cache = 1;      /* Set to handle some access checks directly */
     83 
     84 /* structure to keep track of vfs calls */
     85 
     86 struct coda_op_stats coda_vnodeopstats[CODA_VNODEOPS_SIZE];
     87 
     88 #define MARK_ENTRY(op) (coda_vnodeopstats[op].entries++)
     89 #define MARK_INT_SAT(op) (coda_vnodeopstats[op].sat_intrn++)
     90 #define MARK_INT_FAIL(op) (coda_vnodeopstats[op].unsat_intrn++)
     91 #define MARK_INT_GEN(op) (coda_vnodeopstats[op].gen_intrn++)
     92 
     93 /* What we are delaying for in printf */
     94 int coda_printf_delay = 0;  /* in microseconds */
     95 int coda_vnop_print_entry = 0;
     96 static int coda_lockdebug = 0;
     97 
     98 #define ENTRY if(coda_vnop_print_entry) myprintf(("Entered %s\n",__func__))
     99 
    100 /* Definition of the vnode operation vector */
    101 
    102 const struct vnodeopv_entry_desc coda_vnodeop_entries[] = {
    103     { &vop_default_desc, coda_vop_error },
    104     { &vop_lookup_desc, coda_lookup },		/* lookup */
    105     { &vop_create_desc, coda_create },		/* create */
    106     { &vop_mknod_desc, coda_vop_error },	/* mknod */
    107     { &vop_open_desc, coda_open },		/* open */
    108     { &vop_close_desc, coda_close },		/* close */
    109     { &vop_access_desc, coda_access },		/* access */
    110     { &vop_getattr_desc, coda_getattr },	/* getattr */
    111     { &vop_setattr_desc, coda_setattr },	/* setattr */
    112     { &vop_read_desc, coda_read },		/* read */
    113     { &vop_write_desc, coda_write },		/* write */
    114     { &vop_fcntl_desc, genfs_fcntl },		/* fcntl */
    115     { &vop_ioctl_desc, coda_ioctl },		/* ioctl */
    116     { &vop_mmap_desc, genfs_mmap },		/* mmap */
    117     { &vop_fsync_desc, coda_fsync },		/* fsync */
    118     { &vop_remove_desc, coda_remove },		/* remove */
    119     { &vop_link_desc, coda_link },		/* link */
    120     { &vop_rename_desc, coda_rename },		/* rename */
    121     { &vop_mkdir_desc, coda_mkdir },		/* mkdir */
    122     { &vop_rmdir_desc, coda_rmdir },		/* rmdir */
    123     { &vop_symlink_desc, coda_symlink },	/* symlink */
    124     { &vop_readdir_desc, coda_readdir },	/* readdir */
    125     { &vop_readlink_desc, coda_readlink },	/* readlink */
    126     { &vop_abortop_desc, coda_abortop },	/* abortop */
    127     { &vop_inactive_desc, coda_inactive },	/* inactive */
    128     { &vop_reclaim_desc, coda_reclaim },	/* reclaim */
    129     { &vop_lock_desc, coda_lock },		/* lock */
    130     { &vop_unlock_desc, coda_unlock },		/* unlock */
    131     { &vop_bmap_desc, coda_bmap },		/* bmap */
    132     { &vop_strategy_desc, coda_strategy },	/* strategy */
    133     { &vop_print_desc, coda_vop_error },	/* print */
    134     { &vop_islocked_desc, coda_islocked },	/* islocked */
    135     { &vop_pathconf_desc, coda_vop_error },	/* pathconf */
    136     { &vop_advlock_desc, coda_vop_nop },	/* advlock */
    137     { &vop_bwrite_desc, coda_vop_error },	/* bwrite */
    138     { &vop_seek_desc, genfs_seek },		/* seek */
    139     { &vop_poll_desc, genfs_poll },		/* poll */
    140     { &vop_getpages_desc, coda_getpages },	/* getpages */
    141     { &vop_putpages_desc, coda_putpages },	/* putpages */
    142     { NULL, NULL }
    143 };
    144 
    145 const struct vnodeopv_desc coda_vnodeop_opv_desc =
    146         { &coda_vnodeop_p, coda_vnodeop_entries };
    147 
    148 /* Definitions of NetBSD vnodeop interfaces */
    149 
    150 /*
    151  * A generic error routine.  Return EIO without looking at arguments.
    152  */
    153 int
    154 coda_vop_error(void *anon) {
    155     struct vnodeop_desc **desc = (struct vnodeop_desc **)anon;
    156 
    157     if (codadebug) {
    158 	myprintf(("coda_vop_error: Vnode operation %s called (error).\n",
    159 		  (*desc)->vdesc_name));
    160     }
    161 
    162     return EIO;
    163 }
    164 
    165 /* A generic do-nothing. */
    166 int
    167 coda_vop_nop(void *anon) {
    168     struct vnodeop_desc **desc = (struct vnodeop_desc **)anon;
    169 
    170     if (codadebug) {
    171 	myprintf(("Vnode operation %s called, but unsupported\n",
    172 		  (*desc)->vdesc_name));
    173     }
    174    return (0);
    175 }
    176 
    177 int
    178 coda_vnodeopstats_init(void)
    179 {
    180 	int i;
    181 
    182 	for(i=0;i<CODA_VNODEOPS_SIZE;i++) {
    183 		coda_vnodeopstats[i].opcode = i;
    184 		coda_vnodeopstats[i].entries = 0;
    185 		coda_vnodeopstats[i].sat_intrn = 0;
    186 		coda_vnodeopstats[i].unsat_intrn = 0;
    187 		coda_vnodeopstats[i].gen_intrn = 0;
    188 	}
    189 
    190 	return 0;
    191 }
    192 
    193 /*
    194  * XXX The entire relationship between VOP_OPEN and having a container
    195  * file (via venus_open) needs to be reexamined.  In particular, it's
    196  * valid to open/mmap/close and then reference.  Instead of doing
    197  * VOP_OPEN when getpages needs a container, we should do the
    198  * venus_open part, and record that the vnode has opened the container
    199  * for getpages, and do the matching logical close on coda_inactive.
    200  * Further, coda_rdwr needs a container file, and sometimes needs to
    201  * do the equivalent of open (core dumps).
    202  */
    203 /*
    204  * coda_open calls Venus to return the device and inode of the
    205  * container file, and then obtains a vnode for that file.  The
    206  * container vnode is stored in the coda vnode, and a reference is
    207  * added for each open file.
    208  */
    209 int
    210 coda_open(void *v)
    211 {
    212     /*
    213      * NetBSD can pass the O_EXCL flag in mode, even though the check
    214      * has already happened.  Venus defensively assumes that if open
    215      * is passed the EXCL, it must be a bug.  We strip the flag here.
    216      */
    217 /* true args */
    218     struct vop_open_args *ap = v;
    219     struct vnode *vp = ap->a_vp;
    220     struct cnode *cp = VTOC(vp);
    221     int flag = ap->a_mode & (~O_EXCL);
    222     kauth_cred_t cred = ap->a_cred;
    223 /* locals */
    224     int error;
    225     dev_t dev;			/* container file device, inode, vnode */
    226     ino_t inode;
    227     struct vnode *container_vp;
    228 
    229     MARK_ENTRY(CODA_OPEN_STATS);
    230 
    231     /* Check for open of control file. */
    232     if (IS_CTL_VP(vp)) {
    233 	/* if (WRITABLE(flag)) */
    234 	if (flag & (FWRITE | O_TRUNC | O_CREAT | O_EXCL)) {
    235 	    MARK_INT_FAIL(CODA_OPEN_STATS);
    236 	    return(EACCES);
    237 	}
    238 	MARK_INT_SAT(CODA_OPEN_STATS);
    239 	return(0);
    240     }
    241 
    242     error = venus_open(vtomi(vp), &cp->c_fid, flag, cred, curlwp, &dev, &inode);
    243     if (error)
    244 	return (error);
    245     if (!error) {
    246 	    CODADEBUG(CODA_OPEN,
    247 		myprintf(("open: dev 0x%llx inode %llu result %d\n",
    248 	        (unsigned long long)dev, (unsigned long long)inode, error));)
    249     }
    250 
    251     /*
    252      * Obtain locked and referenced container vnode from container
    253      * device/inode.
    254      */
    255     error = coda_grab_vnode(dev, inode, &container_vp);
    256     if (error)
    257 	return (error);
    258 
    259     /* Save the vnode pointer for the container file. */
    260     if (cp->c_ovp == NULL) {
    261 	cp->c_ovp = container_vp;
    262     } else {
    263 	if (cp->c_ovp != container_vp)
    264 	    /*
    265 	     * Perhaps venus returned a different container, or
    266 	     * something else went wrong.
    267 	     */
    268 	    panic("coda_open: cp->c_ovp != container_vp");
    269     }
    270     cp->c_ocount++;
    271 
    272     /* Flush the attribute cache if writing the file. */
    273     if (flag & FWRITE) {
    274 	cp->c_owrite++;
    275 	cp->c_flags &= ~C_VATTR;
    276     }
    277 
    278     /*
    279      * Save the <device, inode> pair for the container file to speed
    280      * up subsequent reads while closed (mmap, program execution).
    281      * This is perhaps safe because venus will invalidate the node
    282      * before changing the container file mapping.
    283      */
    284     cp->c_device = dev;
    285     cp->c_inode = inode;
    286 
    287     /* Open the container file. */
    288     error = VOP_OPEN(container_vp, flag, cred);
    289     /*
    290      * Drop the lock on the container, after we have done VOP_OPEN
    291      * (which requires a locked vnode).
    292      */
    293     VOP_UNLOCK(container_vp);
    294     return(error);
    295 }
    296 
    297 /*
    298  * Close the cache file used for I/O and notify Venus.
    299  */
    300 int
    301 coda_close(void *v)
    302 {
    303 /* true args */
    304     struct vop_close_args *ap = v;
    305     struct vnode *vp = ap->a_vp;
    306     struct cnode *cp = VTOC(vp);
    307     int flag = ap->a_fflag;
    308     kauth_cred_t cred = ap->a_cred;
    309 /* locals */
    310     int error;
    311 
    312     MARK_ENTRY(CODA_CLOSE_STATS);
    313 
    314     /* Check for close of control file. */
    315     if (IS_CTL_VP(vp)) {
    316 	MARK_INT_SAT(CODA_CLOSE_STATS);
    317 	return(0);
    318     }
    319 
    320     /*
    321      * XXX The IS_UNMOUNTING part of this is very suspect.
    322      */
    323     if (IS_UNMOUNTING(cp)) {
    324 	if (cp->c_ovp) {
    325 #ifdef	CODA_VERBOSE
    326 	    printf("coda_close: destroying container ref %d, ufs vp %p of vp %p/cp %p\n",
    327 		    vp->v_usecount, cp->c_ovp, vp, cp);
    328 #endif
    329 #ifdef	hmm
    330 	    vgone(cp->c_ovp);
    331 #else
    332 	    vn_lock(cp->c_ovp, LK_EXCLUSIVE | LK_RETRY);
    333 	    VOP_CLOSE(cp->c_ovp, flag, cred); /* Do errors matter here? */
    334 	    vput(cp->c_ovp);
    335 #endif
    336 	} else {
    337 #ifdef	CODA_VERBOSE
    338 	    printf("coda_close: NO container vp %p/cp %p\n", vp, cp);
    339 #endif
    340 	}
    341 	return ENODEV;
    342     }
    343 
    344     /* Lock the container node, and VOP_CLOSE it. */
    345     vn_lock(cp->c_ovp, LK_EXCLUSIVE | LK_RETRY);
    346     VOP_CLOSE(cp->c_ovp, flag, cred); /* Do errors matter here? */
    347     /*
    348      * Drop the lock we just obtained, and vrele the container vnode.
    349      * Decrement reference counts, and clear container vnode pointer on
    350      * last close.
    351      */
    352     vput(cp->c_ovp);
    353     if (flag & FWRITE)
    354 	--cp->c_owrite;
    355     if (--cp->c_ocount == 0)
    356 	cp->c_ovp = NULL;
    357 
    358     error = venus_close(vtomi(vp), &cp->c_fid, flag, cred, curlwp);
    359 
    360     CODADEBUG(CODA_CLOSE, myprintf(("close: result %d\n",error)); )
    361     return(error);
    362 }
    363 
    364 int
    365 coda_read(void *v)
    366 {
    367     struct vop_read_args *ap = v;
    368 
    369     ENTRY;
    370     return(coda_rdwr(ap->a_vp, ap->a_uio, UIO_READ,
    371 		    ap->a_ioflag, ap->a_cred, curlwp));
    372 }
    373 
    374 int
    375 coda_write(void *v)
    376 {
    377     struct vop_write_args *ap = v;
    378 
    379     ENTRY;
    380     return(coda_rdwr(ap->a_vp, ap->a_uio, UIO_WRITE,
    381 		    ap->a_ioflag, ap->a_cred, curlwp));
    382 }
    383 
    384 int
    385 coda_rdwr(struct vnode *vp, struct uio *uiop, enum uio_rw rw, int ioflag,
    386 	kauth_cred_t cred, struct lwp *l)
    387 {
    388 /* upcall decl */
    389   /* NOTE: container file operation!!! */
    390 /* locals */
    391     struct cnode *cp = VTOC(vp);
    392     struct vnode *cfvp = cp->c_ovp;
    393     struct proc *p = l->l_proc;
    394     int opened_internally = 0;
    395     int error = 0;
    396 
    397     MARK_ENTRY(CODA_RDWR_STATS);
    398 
    399     CODADEBUG(CODA_RDWR, myprintf(("coda_rdwr(%d, %p, %lu, %lld)\n", rw,
    400 			      uiop->uio_iov->iov_base,
    401 			      (unsigned long) uiop->uio_resid,
    402 			      (long long) uiop->uio_offset)); )
    403 
    404     /* Check for rdwr of control object. */
    405     if (IS_CTL_VP(vp)) {
    406 	MARK_INT_FAIL(CODA_RDWR_STATS);
    407 	return(EINVAL);
    408     }
    409 
    410     /* Redirect the request to UFS. */
    411 
    412     /*
    413      * If file is not already open this must be a page
    414      * {read,write} request.  Iget the cache file's inode
    415      * pointer if we still have its <device, inode> pair.
    416      * Otherwise, we must do an internal open to derive the
    417      * pair.
    418      * XXX Integrate this into a coherent strategy for container
    419      * file acquisition.
    420      */
    421     if (cfvp == NULL) {
    422 	/*
    423 	 * If we're dumping core, do the internal open. Otherwise
    424 	 * venus won't have the correct size of the core when
    425 	 * it's completely written.
    426 	 */
    427 	if (cp->c_inode != 0 && !(p && (p->p_acflag & ACORE))) {
    428 	    printf("coda_rdwr: grabbing container vnode, losing reference\n");
    429 	    /* Get locked and refed vnode. */
    430 	    error = coda_grab_vnode(cp->c_device, cp->c_inode, &cfvp);
    431 	    if (error) {
    432 		MARK_INT_FAIL(CODA_RDWR_STATS);
    433 		return(error);
    434 	    }
    435 	    /*
    436 	     * Drop lock.
    437 	     * XXX Where is reference released.
    438 	     */
    439 	    VOP_UNLOCK(cfvp);
    440 	}
    441 	else {
    442 	    printf("coda_rdwr: internal VOP_OPEN\n");
    443 	    opened_internally = 1;
    444 	    MARK_INT_GEN(CODA_OPEN_STATS);
    445 	    error = VOP_OPEN(vp, (rw == UIO_READ ? FREAD : FWRITE), cred);
    446 #ifdef	CODA_VERBOSE
    447 printf("coda_rdwr: Internally Opening %p\n", vp);
    448 #endif
    449 	    if (error) {
    450 		MARK_INT_FAIL(CODA_RDWR_STATS);
    451 		return(error);
    452 	    }
    453 	    cfvp = cp->c_ovp;
    454 	}
    455     }
    456 
    457     /* Have UFS handle the call. */
    458     CODADEBUG(CODA_RDWR, myprintf(("indirect rdwr: fid = %s, refcnt = %d\n",
    459 			coda_f2s(&cp->c_fid), CTOV(cp)->v_usecount)); )
    460 
    461     if (rw == UIO_READ) {
    462 	error = VOP_READ(cfvp, uiop, ioflag, cred);
    463     } else {
    464 	error = VOP_WRITE(cfvp, uiop, ioflag, cred);
    465     }
    466 
    467     if (error)
    468 	MARK_INT_FAIL(CODA_RDWR_STATS);
    469     else
    470 	MARK_INT_SAT(CODA_RDWR_STATS);
    471 
    472     /* Do an internal close if necessary. */
    473     if (opened_internally) {
    474 	MARK_INT_GEN(CODA_CLOSE_STATS);
    475 	(void)VOP_CLOSE(vp, (rw == UIO_READ ? FREAD : FWRITE), cred);
    476     }
    477 
    478     /* Invalidate cached attributes if writing. */
    479     if (rw == UIO_WRITE)
    480 	cp->c_flags &= ~C_VATTR;
    481     return(error);
    482 }
    483 
    484 int
    485 coda_ioctl(void *v)
    486 {
    487 /* true args */
    488     struct vop_ioctl_args *ap = v;
    489     struct vnode *vp = ap->a_vp;
    490     int com = ap->a_command;
    491     void *data = ap->a_data;
    492     int flag = ap->a_fflag;
    493     kauth_cred_t cred = ap->a_cred;
    494 /* locals */
    495     int error;
    496     struct vnode *tvp;
    497     struct PioctlData *iap = (struct PioctlData *)data;
    498     namei_simple_flags_t sflags;
    499 
    500     MARK_ENTRY(CODA_IOCTL_STATS);
    501 
    502     CODADEBUG(CODA_IOCTL, myprintf(("in coda_ioctl on %s\n", iap->path));)
    503 
    504     /* Don't check for operation on a dying object, for ctlvp it
    505        shouldn't matter */
    506 
    507     /* Must be control object to succeed. */
    508     if (!IS_CTL_VP(vp)) {
    509 	MARK_INT_FAIL(CODA_IOCTL_STATS);
    510 	CODADEBUG(CODA_IOCTL, myprintf(("coda_ioctl error: vp != ctlvp"));)
    511 	    return (EOPNOTSUPP);
    512     }
    513     /* Look up the pathname. */
    514 
    515     /* Should we use the name cache here? It would get it from
    516        lookupname sooner or later anyway, right? */
    517 
    518     sflags = iap->follow ? NSM_FOLLOW_NOEMULROOT : NSM_NOFOLLOW_NOEMULROOT;
    519     error = namei_simple_user(iap->path, sflags, &tvp);
    520 
    521     if (error) {
    522 	MARK_INT_FAIL(CODA_IOCTL_STATS);
    523 	CODADEBUG(CODA_IOCTL, myprintf(("coda_ioctl error: lookup returns %d\n",
    524 				   error));)
    525 	return(error);
    526     }
    527 
    528     /*
    529      * Make sure this is a coda style cnode, but it may be a
    530      * different vfsp
    531      */
    532     /* XXX: this totally violates the comment about vtagtype in vnode.h */
    533     if (tvp->v_tag != VT_CODA) {
    534 	vrele(tvp);
    535 	MARK_INT_FAIL(CODA_IOCTL_STATS);
    536 	CODADEBUG(CODA_IOCTL,
    537 		 myprintf(("coda_ioctl error: %s not a coda object\n",
    538 			iap->path));)
    539 	return(EINVAL);
    540     }
    541 
    542     if (iap->vi.in_size > VC_MAXDATASIZE || iap->vi.out_size > VC_MAXDATASIZE) {
    543 	vrele(tvp);
    544 	return(EINVAL);
    545     }
    546     error = venus_ioctl(vtomi(tvp), &((VTOC(tvp))->c_fid), com, flag, data,
    547 	cred, curlwp);
    548 
    549     if (error)
    550 	MARK_INT_FAIL(CODA_IOCTL_STATS);
    551     else
    552 	CODADEBUG(CODA_IOCTL, myprintf(("Ioctl returns %d \n", error)); )
    553 
    554     vrele(tvp);
    555     return(error);
    556 }
    557 
    558 /*
    559  * To reduce the cost of a user-level venus;we cache attributes in
    560  * the kernel.  Each cnode has storage allocated for an attribute. If
    561  * c_vattr is valid, return a reference to it. Otherwise, get the
    562  * attributes from venus and store them in the cnode.  There is some
    563  * question if this method is a security leak. But I think that in
    564  * order to make this call, the user must have done a lookup and
    565  * opened the file, and therefore should already have access.
    566  */
    567 int
    568 coda_getattr(void *v)
    569 {
    570 /* true args */
    571     struct vop_getattr_args *ap = v;
    572     struct vnode *vp = ap->a_vp;
    573     struct cnode *cp = VTOC(vp);
    574     struct vattr *vap = ap->a_vap;
    575     kauth_cred_t cred = ap->a_cred;
    576 /* locals */
    577     int error;
    578 
    579     MARK_ENTRY(CODA_GETATTR_STATS);
    580 
    581     /* Check for getattr of control object. */
    582     if (IS_CTL_VP(vp)) {
    583 	MARK_INT_FAIL(CODA_GETATTR_STATS);
    584 	return(ENOENT);
    585     }
    586 
    587     /* Check to see if the attributes have already been cached */
    588     if (VALID_VATTR(cp)) {
    589 	CODADEBUG(CODA_GETATTR, { myprintf(("attr cache hit: %s\n",
    590 					coda_f2s(&cp->c_fid)));});
    591 	CODADEBUG(CODA_GETATTR, if (!(codadebug & ~CODA_GETATTR))
    592 		 print_vattr(&cp->c_vattr); );
    593 
    594 	*vap = cp->c_vattr;
    595 	MARK_INT_SAT(CODA_GETATTR_STATS);
    596 	return(0);
    597     }
    598 
    599     error = venus_getattr(vtomi(vp), &cp->c_fid, cred, curlwp, vap);
    600 
    601     if (!error) {
    602 	CODADEBUG(CODA_GETATTR, myprintf(("getattr miss %s: result %d\n",
    603 				     coda_f2s(&cp->c_fid), error)); )
    604 
    605 	CODADEBUG(CODA_GETATTR, if (!(codadebug & ~CODA_GETATTR))
    606 		 print_vattr(vap);	);
    607 
    608 	/* If not open for write, store attributes in cnode */
    609 	if ((cp->c_owrite == 0) && (coda_attr_cache)) {
    610 	    cp->c_vattr = *vap;
    611 	    cp->c_flags |= C_VATTR;
    612 	}
    613 
    614     }
    615     return(error);
    616 }
    617 
    618 int
    619 coda_setattr(void *v)
    620 {
    621 /* true args */
    622     struct vop_setattr_args *ap = v;
    623     struct vnode *vp = ap->a_vp;
    624     struct cnode *cp = VTOC(vp);
    625     struct vattr *vap = ap->a_vap;
    626     kauth_cred_t cred = ap->a_cred;
    627 /* locals */
    628     int error;
    629 
    630     MARK_ENTRY(CODA_SETATTR_STATS);
    631 
    632     /* Check for setattr of control object. */
    633     if (IS_CTL_VP(vp)) {
    634 	MARK_INT_FAIL(CODA_SETATTR_STATS);
    635 	return(ENOENT);
    636     }
    637 
    638     if (codadebug & CODADBGMSK(CODA_SETATTR)) {
    639 	print_vattr(vap);
    640     }
    641     error = venus_setattr(vtomi(vp), &cp->c_fid, vap, cred, curlwp);
    642 
    643     if (!error)
    644 	cp->c_flags &= ~C_VATTR;
    645 
    646     CODADEBUG(CODA_SETATTR,	myprintf(("setattr %d\n", error)); )
    647     return(error);
    648 }
    649 
    650 int
    651 coda_access(void *v)
    652 {
    653 /* true args */
    654     struct vop_access_args *ap = v;
    655     struct vnode *vp = ap->a_vp;
    656     struct cnode *cp = VTOC(vp);
    657     int mode = ap->a_mode;
    658     kauth_cred_t cred = ap->a_cred;
    659 /* locals */
    660     int error;
    661 
    662     MARK_ENTRY(CODA_ACCESS_STATS);
    663 
    664     /* Check for access of control object.  Only read access is
    665        allowed on it. */
    666     if (IS_CTL_VP(vp)) {
    667 	/* bogus hack - all will be marked as successes */
    668 	MARK_INT_SAT(CODA_ACCESS_STATS);
    669 	return(((mode & VREAD) && !(mode & (VWRITE | VEXEC)))
    670 	       ? 0 : EACCES);
    671     }
    672 
    673     /*
    674      * if the file is a directory, and we are checking exec (eg lookup)
    675      * access, and the file is in the namecache, then the user must have
    676      * lookup access to it.
    677      */
    678     if (coda_access_cache) {
    679 	if ((vp->v_type == VDIR) && (mode & VEXEC)) {
    680 	    if (coda_nc_lookup(cp, ".", 1, cred)) {
    681 		MARK_INT_SAT(CODA_ACCESS_STATS);
    682 		return(0);                     /* it was in the cache */
    683 	    }
    684 	}
    685     }
    686 
    687     error = venus_access(vtomi(vp), &cp->c_fid, mode, cred, curlwp);
    688 
    689     return(error);
    690 }
    691 
    692 /*
    693  * CODA abort op, called after namei() when a CREATE/DELETE isn't actually
    694  * done. If a buffer has been saved in anticipation of a coda_create or
    695  * a coda_remove, delete it.
    696  */
    697 /* ARGSUSED */
    698 int
    699 coda_abortop(void *v)
    700 {
    701 /* true args */
    702     struct vop_abortop_args /* {
    703 	struct vnode *a_dvp;
    704 	struct componentname *a_cnp;
    705     } */ *ap = v;
    706 
    707     (void)ap;
    708 /* upcall decl */
    709 /* locals */
    710 
    711     return (0);
    712 }
    713 
    714 int
    715 coda_readlink(void *v)
    716 {
    717 /* true args */
    718     struct vop_readlink_args *ap = v;
    719     struct vnode *vp = ap->a_vp;
    720     struct cnode *cp = VTOC(vp);
    721     struct uio *uiop = ap->a_uio;
    722     kauth_cred_t cred = ap->a_cred;
    723 /* locals */
    724     struct lwp *l = curlwp;
    725     int error;
    726     char *str;
    727     int len;
    728 
    729     MARK_ENTRY(CODA_READLINK_STATS);
    730 
    731     /* Check for readlink of control object. */
    732     if (IS_CTL_VP(vp)) {
    733 	MARK_INT_FAIL(CODA_READLINK_STATS);
    734 	return(ENOENT);
    735     }
    736 
    737     if ((coda_symlink_cache) && (VALID_SYMLINK(cp))) { /* symlink was cached */
    738 	uiop->uio_rw = UIO_READ;
    739 	error = uiomove(cp->c_symlink, (int)cp->c_symlen, uiop);
    740 	if (error)
    741 	    MARK_INT_FAIL(CODA_READLINK_STATS);
    742 	else
    743 	    MARK_INT_SAT(CODA_READLINK_STATS);
    744 	return(error);
    745     }
    746 
    747     error = venus_readlink(vtomi(vp), &cp->c_fid, cred, l, &str, &len);
    748 
    749     if (!error) {
    750 	uiop->uio_rw = UIO_READ;
    751 	error = uiomove(str, len, uiop);
    752 
    753 	if (coda_symlink_cache) {
    754 	    cp->c_symlink = str;
    755 	    cp->c_symlen = len;
    756 	    cp->c_flags |= C_SYMLINK;
    757 	} else
    758 	    CODA_FREE(str, len);
    759     }
    760 
    761     CODADEBUG(CODA_READLINK, myprintf(("in readlink result %d\n",error));)
    762     return(error);
    763 }
    764 
    765 int
    766 coda_fsync(void *v)
    767 {
    768 /* true args */
    769     struct vop_fsync_args *ap = v;
    770     struct vnode *vp = ap->a_vp;
    771     struct cnode *cp = VTOC(vp);
    772     kauth_cred_t cred = ap->a_cred;
    773 /* locals */
    774     struct vnode *convp = cp->c_ovp;
    775     int error;
    776 
    777     MARK_ENTRY(CODA_FSYNC_STATS);
    778 
    779     /* Check for fsync on an unmounting object */
    780     /* The NetBSD kernel, in it's infinite wisdom, can try to fsync
    781      * after an unmount has been initiated.  This is a Bad Thing,
    782      * which we have to avoid.  Not a legitimate failure for stats.
    783      */
    784     if (IS_UNMOUNTING(cp)) {
    785 	return(ENODEV);
    786     }
    787 
    788     /* Check for fsync of control object. */
    789     if (IS_CTL_VP(vp)) {
    790 	MARK_INT_SAT(CODA_FSYNC_STATS);
    791 	return(0);
    792     }
    793 
    794     if (convp)
    795     	VOP_FSYNC(convp, cred, MNT_WAIT, 0, 0);
    796 
    797     /*
    798      * We can expect fsync on any vnode at all if venus is pruging it.
    799      * Venus can't very well answer the fsync request, now can it?
    800      * Hopefully, it won't have to, because hopefully, venus preserves
    801      * the (possibly untrue) invariant that it never purges an open
    802      * vnode.  Hopefully.
    803      */
    804     if (cp->c_flags & C_PURGING) {
    805 	return(0);
    806     }
    807 
    808     error = venus_fsync(vtomi(vp), &cp->c_fid, cred, curlwp);
    809 
    810     CODADEBUG(CODA_FSYNC, myprintf(("in fsync result %d\n",error)); );
    811     return(error);
    812 }
    813 
    814 /*
    815  * vp is locked on entry, and we must unlock it.
    816  * XXX This routine is suspect and probably needs rewriting.
    817  */
    818 int
    819 coda_inactive(void *v)
    820 {
    821 /* true args */
    822     struct vop_inactive_args *ap = v;
    823     struct vnode *vp = ap->a_vp;
    824     struct cnode *cp = VTOC(vp);
    825     kauth_cred_t cred __unused = NULL;
    826 
    827     /* We don't need to send inactive to venus - DCS */
    828     MARK_ENTRY(CODA_INACTIVE_STATS);
    829 
    830     if (IS_CTL_VP(vp)) {
    831 	MARK_INT_SAT(CODA_INACTIVE_STATS);
    832 	return 0;
    833     }
    834 
    835     CODADEBUG(CODA_INACTIVE, myprintf(("in inactive, %s, vfsp %p\n",
    836 				  coda_f2s(&cp->c_fid), vp->v_mount));)
    837 
    838     /* If an array has been allocated to hold the symlink, deallocate it */
    839     if ((coda_symlink_cache) && (VALID_SYMLINK(cp))) {
    840 	if (cp->c_symlink == NULL)
    841 	    panic("coda_inactive: null symlink pointer in cnode");
    842 
    843 	CODA_FREE(cp->c_symlink, cp->c_symlen);
    844 	cp->c_flags &= ~C_SYMLINK;
    845 	cp->c_symlen = 0;
    846     }
    847 
    848     /* Remove it from the table so it can't be found. */
    849     coda_unsave(cp);
    850     if (vp->v_mount->mnt_data == NULL) {
    851 	myprintf(("Help! vfsp->vfs_data was NULL, but vnode %p wasn't dying\n", vp));
    852 	panic("badness in coda_inactive");
    853     }
    854 
    855     if (IS_UNMOUNTING(cp)) {
    856 	/* XXX Do we need to VOP_CLOSE container vnodes? */
    857 	if (vp->v_usecount > 0)
    858 	    printf("coda_inactive: IS_UNMOUNTING %p usecount %d\n",
    859 		   vp, vp->v_usecount);
    860 	if (cp->c_ovp != NULL)
    861 	    printf("coda_inactive: %p ovp != NULL\n", vp);
    862 	VOP_UNLOCK(vp);
    863     } else {
    864         /* Sanity checks that perhaps should be panic. */
    865 	if (vp->v_usecount) {
    866 	    printf("coda_inactive: %p usecount %d\n", vp, vp->v_usecount);
    867 	}
    868 	if (cp->c_ovp != NULL) {
    869 	    printf("coda_inactive: %p ovp != NULL\n", vp);
    870 	}
    871 	VOP_UNLOCK(vp);
    872 	*ap->a_recycle = true;
    873     }
    874 
    875     MARK_INT_SAT(CODA_INACTIVE_STATS);
    876     return(0);
    877 }
    878 
    879 /*
    880  * Coda does not use the normal namecache, but a private version.
    881  * Consider how to use the standard facility instead.
    882  */
    883 int
    884 coda_lookup(void *v)
    885 {
    886 /* true args */
    887     struct vop_lookup_args *ap = v;
    888     /* (locked) vnode of dir in which to do lookup */
    889     struct vnode *dvp = ap->a_dvp;
    890     struct cnode *dcp = VTOC(dvp);
    891     /* output variable for result */
    892     struct vnode **vpp = ap->a_vpp;
    893     /* name to lookup */
    894     struct componentname *cnp = ap->a_cnp;
    895     kauth_cred_t cred = cnp->cn_cred;
    896     struct lwp *l = curlwp;
    897 /* locals */
    898     struct cnode *cp;
    899     const char *nm = cnp->cn_nameptr;
    900     int len = cnp->cn_namelen;
    901     int flags = cnp->cn_flags;
    902     int isdot;
    903     CodaFid VFid;
    904     int	vtype;
    905     int error = 0;
    906 
    907     MARK_ENTRY(CODA_LOOKUP_STATS);
    908 
    909     CODADEBUG(CODA_LOOKUP, myprintf(("lookup: %s in %s\n",
    910 				   nm, coda_f2s(&dcp->c_fid))););
    911 
    912     /*
    913      * XXX componentname flags in MODMASK are not handled at all
    914      */
    915 
    916     /*
    917      * The overall strategy is to switch on the lookup type and get a
    918      * result vnode that is vref'd but not locked.  Then, the code at
    919      * exit: switches on ., .., and regular lookups and does the right
    920      * locking.
    921      */
    922 
    923     /* Check for lookup of control object. */
    924     if (IS_CTL_NAME(dvp, nm, len)) {
    925 	*vpp = coda_ctlvp;
    926 	vref(*vpp);
    927 	MARK_INT_SAT(CODA_LOOKUP_STATS);
    928 	goto exit;
    929     }
    930 
    931     /* Avoid trying to hand venus an unreasonably long name. */
    932     if (len+1 > CODA_MAXNAMLEN) {
    933 	MARK_INT_FAIL(CODA_LOOKUP_STATS);
    934 	CODADEBUG(CODA_LOOKUP, myprintf(("name too long: lookup, %s (%s)\n",
    935 				    coda_f2s(&dcp->c_fid), nm)););
    936 	*vpp = (struct vnode *)0;
    937 	error = EINVAL;
    938 	goto exit;
    939     }
    940 
    941     /*
    942      * XXX Check for DOT lookups, and short circuit all the caches,
    943      * just doing an extra vref.  (venus guarantees that lookup of
    944      * . returns self.)
    945      */
    946     isdot = (len == 1 && nm[0] == '.');
    947 
    948     /*
    949      * Try to resolve the lookup in the minicache.  If that fails, ask
    950      * venus to do the lookup.  XXX The interaction between vnode
    951      * locking and any locking that coda does is not clear.
    952      */
    953     cp = coda_nc_lookup(dcp, nm, len, cred);
    954     if (cp) {
    955 	*vpp = CTOV(cp);
    956 	vref(*vpp);
    957 	CODADEBUG(CODA_LOOKUP,
    958 		 myprintf(("lookup result %d vpp %p\n",error,*vpp));)
    959     } else {
    960 	/* The name wasn't cached, so ask Venus. */
    961 	error = venus_lookup(vtomi(dvp), &dcp->c_fid, nm, len, cred, l, &VFid, &vtype);
    962 
    963 	if (error) {
    964 	    MARK_INT_FAIL(CODA_LOOKUP_STATS);
    965 	    CODADEBUG(CODA_LOOKUP, myprintf(("lookup error on %s (%s)%d\n",
    966 					coda_f2s(&dcp->c_fid), nm, error));)
    967 	    *vpp = (struct vnode *)0;
    968 	} else {
    969 	    MARK_INT_SAT(CODA_LOOKUP_STATS);
    970 	    CODADEBUG(CODA_LOOKUP,
    971 		     myprintf(("lookup: %s type %o result %d\n",
    972 			    coda_f2s(&VFid), vtype, error)); )
    973 
    974 	    cp = make_coda_node(&VFid, dvp->v_mount, vtype);
    975 	    *vpp = CTOV(cp);
    976 	    /* vpp is now vrefed. */
    977 
    978 	    /*
    979 	     * Unless this vnode is marked CODA_NOCACHE, enter it into
    980 	     * the coda name cache to avoid a future venus round-trip.
    981 	     * XXX Interaction with componentname NOCACHE is unclear.
    982 	     */
    983 	    if (!(vtype & CODA_NOCACHE))
    984 		coda_nc_enter(VTOC(dvp), nm, len, cred, VTOC(*vpp));
    985 	}
    986     }
    987 
    988  exit:
    989     /*
    990      * If we are creating, and this was the last name to be looked up,
    991      * and the error was ENOENT, then make the leaf NULL and return
    992      * success.
    993      * XXX Check against new lookup rules.
    994      */
    995     if (((cnp->cn_nameiop == CREATE) || (cnp->cn_nameiop == RENAME))
    996 	&& (cnp->cn_flags & ISLASTCN)
    997 	&& (error == ENOENT))
    998     {
    999 	error = EJUSTRETURN;
   1000 	*ap->a_vpp = NULL;
   1001     }
   1002 
   1003     /*
   1004      * If the lookup succeeded, we must generally lock the returned
   1005      * vnode.  This could be a ., .., or normal lookup.  See
   1006      * vnodeops(9) for the details.
   1007      */
   1008     /*
   1009      * XXX LK_RETRY is likely incorrect.  Handle vn_lock failure
   1010      * somehow, and remove LK_RETRY.
   1011      */
   1012     if (!error || (error == EJUSTRETURN)) {
   1013 	/* Lookup has a value and it isn't "."? */
   1014 	if (*ap->a_vpp && (*ap->a_vpp != dvp)) {
   1015 	    if (flags & ISDOTDOT)
   1016 		/* ..: unlock parent */
   1017 		VOP_UNLOCK(dvp);
   1018 	    /* all but .: lock child */
   1019 	    vn_lock(*ap->a_vpp, LK_EXCLUSIVE | LK_RETRY);
   1020 	    if (flags & ISDOTDOT)
   1021 		/* ..: relock parent */
   1022 	        vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY);
   1023 	}
   1024 	/* else .: leave dvp locked */
   1025     } else {
   1026 	/* The lookup failed, so return NULL.  Leave dvp locked. */
   1027 	*ap->a_vpp = NULL;
   1028     }
   1029     return(error);
   1030 }
   1031 
   1032 /*ARGSUSED*/
   1033 int
   1034 coda_create(void *v)
   1035 {
   1036 /* true args */
   1037     struct vop_create_args *ap = v;
   1038     struct vnode *dvp = ap->a_dvp;
   1039     struct cnode *dcp = VTOC(dvp);
   1040     struct vattr *va = ap->a_vap;
   1041     int exclusive = 1;
   1042     int mode = ap->a_vap->va_mode;
   1043     struct vnode **vpp = ap->a_vpp;
   1044     struct componentname  *cnp = ap->a_cnp;
   1045     kauth_cred_t cred = cnp->cn_cred;
   1046     struct lwp *l = curlwp;
   1047 /* locals */
   1048     int error;
   1049     struct cnode *cp;
   1050     const char *nm = cnp->cn_nameptr;
   1051     int len = cnp->cn_namelen;
   1052     CodaFid VFid;
   1053     struct vattr attr;
   1054 
   1055     MARK_ENTRY(CODA_CREATE_STATS);
   1056 
   1057     /* All creates are exclusive XXX */
   1058     /* I'm assuming the 'mode' argument is the file mode bits XXX */
   1059 
   1060     /* Check for create of control object. */
   1061     if (IS_CTL_NAME(dvp, nm, len)) {
   1062 	*vpp = (struct vnode *)0;
   1063 	MARK_INT_FAIL(CODA_CREATE_STATS);
   1064 	return(EACCES);
   1065     }
   1066 
   1067     error = venus_create(vtomi(dvp), &dcp->c_fid, nm, len, exclusive, mode, va, cred, l, &VFid, &attr);
   1068 
   1069     if (!error) {
   1070 
   1071         /*
   1072 	 * XXX Violation of venus/kernel invariants is a difficult case,
   1073 	 * but venus should not be able to cause a panic.
   1074 	 */
   1075 	/* If this is an exclusive create, panic if the file already exists. */
   1076 	/* Venus should have detected the file and reported EEXIST. */
   1077 
   1078 	if ((exclusive == 1) &&
   1079 	    (coda_find(&VFid) != NULL))
   1080 	    panic("cnode existed for newly created file!");
   1081 
   1082 	cp = make_coda_node(&VFid, dvp->v_mount, attr.va_type);
   1083 	*vpp = CTOV(cp);
   1084 
   1085 	/* XXX vnodeops doesn't say this argument can be changed. */
   1086 	/* Update va to reflect the new attributes. */
   1087 	(*va) = attr;
   1088 
   1089 	/* Update the attribute cache and mark it as valid */
   1090 	if (coda_attr_cache) {
   1091 	    VTOC(*vpp)->c_vattr = attr;
   1092 	    VTOC(*vpp)->c_flags |= C_VATTR;
   1093 	}
   1094 
   1095 	/* Invalidate parent's attr cache (modification time has changed). */
   1096 	VTOC(dvp)->c_flags &= ~C_VATTR;
   1097 
   1098 	/* enter the new vnode in the Name Cache */
   1099 	coda_nc_enter(VTOC(dvp), nm, len, cred, VTOC(*vpp));
   1100 
   1101 	CODADEBUG(CODA_CREATE,
   1102 		 myprintf(("create: %s, result %d\n",
   1103 			coda_f2s(&VFid), error)); )
   1104     } else {
   1105 	*vpp = (struct vnode *)0;
   1106 	CODADEBUG(CODA_CREATE, myprintf(("create error %d\n", error));)
   1107     }
   1108 
   1109     /*
   1110      * vnodeops(9) says that we must unlock the parent and lock the child.
   1111      * XXX Should we lock the child first?
   1112      */
   1113     vput(dvp);
   1114     if (!error) {
   1115 	if ((cnp->cn_flags & LOCKLEAF) == 0) {
   1116 	    /* This should not happen; flags are for lookup only. */
   1117 	    printf("coda_create: LOCKLEAF not set!\n");
   1118 	}
   1119 
   1120 	if ((error = vn_lock(*ap->a_vpp, LK_EXCLUSIVE))) {
   1121 	    /* XXX Perhaps avoid this panic. */
   1122 	    panic("coda_create: couldn't lock child");
   1123 	}
   1124     }
   1125 
   1126     return(error);
   1127 }
   1128 
   1129 int
   1130 coda_remove(void *v)
   1131 {
   1132 /* true args */
   1133     struct vop_remove_args *ap = v;
   1134     struct vnode *dvp = ap->a_dvp;
   1135     struct cnode *cp = VTOC(dvp);
   1136     struct vnode *vp = ap->a_vp;
   1137     struct componentname  *cnp = ap->a_cnp;
   1138     kauth_cred_t cred = cnp->cn_cred;
   1139     struct lwp *l = curlwp;
   1140 /* locals */
   1141     int error;
   1142     const char *nm = cnp->cn_nameptr;
   1143     int len = cnp->cn_namelen;
   1144     struct cnode *tp;
   1145 
   1146     MARK_ENTRY(CODA_REMOVE_STATS);
   1147 
   1148     CODADEBUG(CODA_REMOVE, myprintf(("remove: %s in %s\n",
   1149 				   nm, coda_f2s(&cp->c_fid))););
   1150 
   1151     /* Remove the file's entry from the CODA Name Cache */
   1152     /* We're being conservative here, it might be that this person
   1153      * doesn't really have sufficient access to delete the file
   1154      * but we feel zapping the entry won't really hurt anyone -- dcs
   1155      */
   1156     /* I'm gonna go out on a limb here. If a file and a hardlink to it
   1157      * exist, and one is removed, the link count on the other will be
   1158      * off by 1. We could either invalidate the attrs if cached, or
   1159      * fix them. I'll try to fix them. DCS 11/8/94
   1160      */
   1161     tp = coda_nc_lookup(VTOC(dvp), nm, len, cred);
   1162     if (tp) {
   1163 	if (VALID_VATTR(tp)) {	/* If attrs are cached */
   1164 	    if (tp->c_vattr.va_nlink > 1) {	/* If it's a hard link */
   1165 		tp->c_vattr.va_nlink--;
   1166 	    }
   1167 	}
   1168 
   1169 	coda_nc_zapfile(VTOC(dvp), nm, len);
   1170 	/* No need to flush it if it doesn't exist! */
   1171     }
   1172     /* Invalidate the parent's attr cache, the modification time has changed */
   1173     VTOC(dvp)->c_flags &= ~C_VATTR;
   1174 
   1175     /* Check for remove of control object. */
   1176     if (IS_CTL_NAME(dvp, nm, len)) {
   1177 	MARK_INT_FAIL(CODA_REMOVE_STATS);
   1178 	return(ENOENT);
   1179     }
   1180 
   1181     error = venus_remove(vtomi(dvp), &cp->c_fid, nm, len, cred, l);
   1182 
   1183     CODADEBUG(CODA_REMOVE, myprintf(("in remove result %d\n",error)); )
   1184 
   1185     /*
   1186      * Unlock parent and child (avoiding double if ".").
   1187      */
   1188     if (dvp == vp) {
   1189 	vrele(vp);
   1190     } else {
   1191 	vput(vp);
   1192     }
   1193     vput(dvp);
   1194 
   1195     return(error);
   1196 }
   1197 
   1198 /*
   1199  * dvp is the directory where the link is to go, and is locked.
   1200  * vp is the object to be linked to, and is unlocked.
   1201  * At exit, we must unlock dvp, and vput dvp.
   1202  */
   1203 int
   1204 coda_link(void *v)
   1205 {
   1206 /* true args */
   1207     struct vop_link_args *ap = v;
   1208     struct vnode *vp = ap->a_vp;
   1209     struct cnode *cp = VTOC(vp);
   1210     struct vnode *dvp = ap->a_dvp;
   1211     struct cnode *dcp = VTOC(dvp);
   1212     struct componentname *cnp = ap->a_cnp;
   1213     kauth_cred_t cred = cnp->cn_cred;
   1214     struct lwp *l = curlwp;
   1215 /* locals */
   1216     int error;
   1217     const char *nm = cnp->cn_nameptr;
   1218     int len = cnp->cn_namelen;
   1219 
   1220     MARK_ENTRY(CODA_LINK_STATS);
   1221 
   1222     if (codadebug & CODADBGMSK(CODA_LINK)) {
   1223 
   1224 	myprintf(("nb_link:   vp fid: %s\n",
   1225 		  coda_f2s(&cp->c_fid)));
   1226 	myprintf(("nb_link: dvp fid: %s)\n",
   1227 		  coda_f2s(&dcp->c_fid)));
   1228 
   1229     }
   1230     if (codadebug & CODADBGMSK(CODA_LINK)) {
   1231 	myprintf(("link:   vp fid: %s\n",
   1232 		  coda_f2s(&cp->c_fid)));
   1233 	myprintf(("link: dvp fid: %s\n",
   1234 		  coda_f2s(&dcp->c_fid)));
   1235 
   1236     }
   1237 
   1238     /* Check for link to/from control object. */
   1239     if (IS_CTL_NAME(dvp, nm, len) || IS_CTL_VP(vp)) {
   1240 	MARK_INT_FAIL(CODA_LINK_STATS);
   1241 	return(EACCES);
   1242     }
   1243 
   1244     /* If linking . to a name, error out earlier. */
   1245     if (vp == dvp) {
   1246         printf("coda_link vp==dvp\n");
   1247 	error = EISDIR;
   1248 	goto exit;
   1249     }
   1250 
   1251     /* XXX Why does venus_link need the vnode to be locked?*/
   1252     if ((error = vn_lock(vp, LK_EXCLUSIVE)) != 0) {
   1253 	printf("coda_link: couldn't lock vnode %p\n", vp);
   1254 	error = EFAULT;		/* XXX better value */
   1255 	goto exit;
   1256     }
   1257     error = venus_link(vtomi(vp), &cp->c_fid, &dcp->c_fid, nm, len, cred, l);
   1258     VOP_UNLOCK(vp);
   1259 
   1260     /* Invalidate parent's attr cache (the modification time has changed). */
   1261     VTOC(dvp)->c_flags &= ~C_VATTR;
   1262     /* Invalidate child's attr cache (XXX why). */
   1263     VTOC(vp)->c_flags &= ~C_VATTR;
   1264 
   1265     CODADEBUG(CODA_LINK,	myprintf(("in link result %d\n",error)); )
   1266 
   1267 exit:
   1268     vput(dvp);
   1269     return(error);
   1270 }
   1271 
   1272 int
   1273 coda_rename(void *v)
   1274 {
   1275 /* true args */
   1276     struct vop_rename_args *ap = v;
   1277     struct vnode *odvp = ap->a_fdvp;
   1278     struct cnode *odcp = VTOC(odvp);
   1279     struct componentname  *fcnp = ap->a_fcnp;
   1280     struct vnode *ndvp = ap->a_tdvp;
   1281     struct cnode *ndcp = VTOC(ndvp);
   1282     struct componentname  *tcnp = ap->a_tcnp;
   1283     kauth_cred_t cred = fcnp->cn_cred;
   1284     struct lwp *l = curlwp;
   1285 /* true args */
   1286     int error;
   1287     const char *fnm = fcnp->cn_nameptr;
   1288     int flen = fcnp->cn_namelen;
   1289     const char *tnm = tcnp->cn_nameptr;
   1290     int tlen = tcnp->cn_namelen;
   1291 
   1292     MARK_ENTRY(CODA_RENAME_STATS);
   1293 
   1294     /* Hmmm.  The vnodes are already looked up.  Perhaps they are locked?
   1295        This could be Bad. XXX */
   1296 #ifdef OLD_DIAGNOSTIC
   1297     if ((fcnp->cn_cred != tcnp->cn_cred)
   1298 	|| (fcnp->cn_lwp != tcnp->cn_lwp))
   1299     {
   1300 	panic("coda_rename: component names don't agree");
   1301     }
   1302 #endif
   1303 
   1304     /* Check for rename involving control object. */
   1305     if (IS_CTL_NAME(odvp, fnm, flen) || IS_CTL_NAME(ndvp, tnm, tlen)) {
   1306 	MARK_INT_FAIL(CODA_RENAME_STATS);
   1307 	return(EACCES);
   1308     }
   1309 
   1310     /* Problem with moving directories -- need to flush entry for .. */
   1311     if (odvp != ndvp) {
   1312 	struct cnode *ovcp = coda_nc_lookup(VTOC(odvp), fnm, flen, cred);
   1313 	if (ovcp) {
   1314 	    struct vnode *ovp = CTOV(ovcp);
   1315 	    if ((ovp) &&
   1316 		(ovp->v_type == VDIR)) /* If it's a directory */
   1317 		coda_nc_zapfile(VTOC(ovp),"..", 2);
   1318 	}
   1319     }
   1320 
   1321     /* Remove the entries for both source and target files */
   1322     coda_nc_zapfile(VTOC(odvp), fnm, flen);
   1323     coda_nc_zapfile(VTOC(ndvp), tnm, tlen);
   1324 
   1325     /* Invalidate the parent's attr cache, the modification time has changed */
   1326     VTOC(odvp)->c_flags &= ~C_VATTR;
   1327     VTOC(ndvp)->c_flags &= ~C_VATTR;
   1328 
   1329     if (flen+1 > CODA_MAXNAMLEN) {
   1330 	MARK_INT_FAIL(CODA_RENAME_STATS);
   1331 	error = EINVAL;
   1332 	goto exit;
   1333     }
   1334 
   1335     if (tlen+1 > CODA_MAXNAMLEN) {
   1336 	MARK_INT_FAIL(CODA_RENAME_STATS);
   1337 	error = EINVAL;
   1338 	goto exit;
   1339     }
   1340 
   1341     error = venus_rename(vtomi(odvp), &odcp->c_fid, &ndcp->c_fid, fnm, flen, tnm, tlen, cred, l);
   1342 
   1343  exit:
   1344     CODADEBUG(CODA_RENAME, myprintf(("in rename result %d\n",error));)
   1345     /* XXX - do we need to call cache pureg on the moved vnode? */
   1346     cache_purge(ap->a_fvp);
   1347 
   1348     /* It seems to be incumbent on us to drop locks on all four vnodes */
   1349     /* From-vnodes are not locked, only ref'd.  To-vnodes are locked. */
   1350 
   1351     vrele(ap->a_fvp);
   1352     vrele(odvp);
   1353 
   1354     if (ap->a_tvp) {
   1355 	if (ap->a_tvp == ndvp) {
   1356 	    vrele(ap->a_tvp);
   1357 	} else {
   1358 	    vput(ap->a_tvp);
   1359 	}
   1360     }
   1361 
   1362     vput(ndvp);
   1363     return(error);
   1364 }
   1365 
   1366 int
   1367 coda_mkdir(void *v)
   1368 {
   1369 /* true args */
   1370     struct vop_mkdir_args *ap = v;
   1371     struct vnode *dvp = ap->a_dvp;
   1372     struct cnode *dcp = VTOC(dvp);
   1373     struct componentname  *cnp = ap->a_cnp;
   1374     struct vattr *va = ap->a_vap;
   1375     struct vnode **vpp = ap->a_vpp;
   1376     kauth_cred_t cred = cnp->cn_cred;
   1377     struct lwp *l = curlwp;
   1378 /* locals */
   1379     int error;
   1380     const char *nm = cnp->cn_nameptr;
   1381     int len = cnp->cn_namelen;
   1382     struct cnode *cp;
   1383     CodaFid VFid;
   1384     struct vattr ova;
   1385 
   1386     MARK_ENTRY(CODA_MKDIR_STATS);
   1387 
   1388     /* Check for mkdir of target object. */
   1389     if (IS_CTL_NAME(dvp, nm, len)) {
   1390 	*vpp = (struct vnode *)0;
   1391 	MARK_INT_FAIL(CODA_MKDIR_STATS);
   1392 	return(EACCES);
   1393     }
   1394 
   1395     if (len+1 > CODA_MAXNAMLEN) {
   1396 	*vpp = (struct vnode *)0;
   1397 	MARK_INT_FAIL(CODA_MKDIR_STATS);
   1398 	return(EACCES);
   1399     }
   1400 
   1401     error = venus_mkdir(vtomi(dvp), &dcp->c_fid, nm, len, va, cred, l, &VFid, &ova);
   1402 
   1403     if (!error) {
   1404 	if (coda_find(&VFid) != NULL)
   1405 	    panic("cnode existed for newly created directory!");
   1406 
   1407 
   1408 	cp =  make_coda_node(&VFid, dvp->v_mount, va->va_type);
   1409 	*vpp = CTOV(cp);
   1410 
   1411 	/* enter the new vnode in the Name Cache */
   1412 	coda_nc_enter(VTOC(dvp), nm, len, cred, VTOC(*vpp));
   1413 
   1414 	/* as a side effect, enter "." and ".." for the directory */
   1415 	coda_nc_enter(VTOC(*vpp), ".", 1, cred, VTOC(*vpp));
   1416 	coda_nc_enter(VTOC(*vpp), "..", 2, cred, VTOC(dvp));
   1417 
   1418 	if (coda_attr_cache) {
   1419 	    VTOC(*vpp)->c_vattr = ova;		/* update the attr cache */
   1420 	    VTOC(*vpp)->c_flags |= C_VATTR;	/* Valid attributes in cnode */
   1421 	}
   1422 
   1423 	/* Invalidate the parent's attr cache, the modification time has changed */
   1424 	VTOC(dvp)->c_flags &= ~C_VATTR;
   1425 
   1426 	CODADEBUG( CODA_MKDIR, myprintf(("mkdir: %s result %d\n",
   1427 				    coda_f2s(&VFid), error)); )
   1428     } else {
   1429 	*vpp = (struct vnode *)0;
   1430 	CODADEBUG(CODA_MKDIR, myprintf(("mkdir error %d\n",error));)
   1431     }
   1432 
   1433     /*
   1434      * Currently, all mkdirs explicitly vput their dvp's.
   1435      * It also appears that we *must* lock the vpp, since
   1436      * lockleaf isn't set, but someone down the road is going
   1437      * to try to unlock the new directory.
   1438      */
   1439     vput(dvp);
   1440     if (!error) {
   1441 	if ((error = vn_lock(*ap->a_vpp, LK_EXCLUSIVE))) {
   1442 	    panic("coda_mkdir: couldn't lock child");
   1443 	}
   1444     }
   1445 
   1446     return(error);
   1447 }
   1448 
   1449 int
   1450 coda_rmdir(void *v)
   1451 {
   1452 /* true args */
   1453     struct vop_rmdir_args *ap = v;
   1454     struct vnode *dvp = ap->a_dvp;
   1455     struct cnode *dcp = VTOC(dvp);
   1456     struct vnode *vp = ap->a_vp;
   1457     struct componentname  *cnp = ap->a_cnp;
   1458     kauth_cred_t cred = cnp->cn_cred;
   1459     struct lwp *l = curlwp;
   1460 /* true args */
   1461     int error;
   1462     const char *nm = cnp->cn_nameptr;
   1463     int len = cnp->cn_namelen;
   1464     struct cnode *cp;
   1465 
   1466     MARK_ENTRY(CODA_RMDIR_STATS);
   1467 
   1468     /* Check for rmdir of control object. */
   1469     if (IS_CTL_NAME(dvp, nm, len)) {
   1470 	MARK_INT_FAIL(CODA_RMDIR_STATS);
   1471 	return(ENOENT);
   1472     }
   1473 
   1474     /* Can't remove . in self. */
   1475     if (dvp == vp) {
   1476 	printf("coda_rmdir: dvp == vp\n");
   1477 	error = EINVAL;
   1478 	goto exit;
   1479     }
   1480 
   1481     /*
   1482      * The caller may not have adequate permissions, and the venus
   1483      * operation may fail, but it doesn't hurt from a correctness
   1484      * viewpoint to invalidate cache entries.
   1485      * XXX Why isn't this done after the venus_rmdir call?
   1486      */
   1487     /* Look up child in name cache (by name, from parent). */
   1488     cp = coda_nc_lookup(dcp, nm, len, cred);
   1489     /* If found, remove all children of the child (., ..). */
   1490     if (cp) coda_nc_zapParentfid(&(cp->c_fid), NOT_DOWNCALL);
   1491 
   1492     /* Remove child's own entry. */
   1493     coda_nc_zapfile(dcp, nm, len);
   1494 
   1495     /* Invalidate parent's attr cache (the modification time has changed). */
   1496     dcp->c_flags &= ~C_VATTR;
   1497 
   1498     error = venus_rmdir(vtomi(dvp), &dcp->c_fid, nm, len, cred, l);
   1499 
   1500     CODADEBUG(CODA_RMDIR, myprintf(("in rmdir result %d\n", error)); )
   1501 
   1502 exit:
   1503     /* vput both vnodes */
   1504     vput(dvp);
   1505     if (dvp == vp) {
   1506 	vrele(vp);
   1507     } else {
   1508 	vput(vp);
   1509     }
   1510 
   1511     return(error);
   1512 }
   1513 
   1514 int
   1515 coda_symlink(void *v)
   1516 {
   1517 /* true args */
   1518     struct vop_symlink_args *ap = v;
   1519     struct vnode *dvp = ap->a_dvp;
   1520     struct cnode *dcp = VTOC(dvp);
   1521     /* a_vpp is used in place below */
   1522     struct componentname *cnp = ap->a_cnp;
   1523     struct vattr *tva = ap->a_vap;
   1524     char *path = ap->a_target;
   1525     kauth_cred_t cred = cnp->cn_cred;
   1526     struct lwp *l = curlwp;
   1527 /* locals */
   1528     int error;
   1529     u_long saved_cn_flags;
   1530     const char *nm = cnp->cn_nameptr;
   1531     int len = cnp->cn_namelen;
   1532     int plen = strlen(path);
   1533 
   1534     /*
   1535      * Here's the strategy for the moment: perform the symlink, then
   1536      * do a lookup to grab the resulting vnode.  I know this requires
   1537      * two communications with Venus for a new sybolic link, but
   1538      * that's the way the ball bounces.  I don't yet want to change
   1539      * the way the Mach symlink works.  When Mach support is
   1540      * deprecated, we should change symlink so that the common case
   1541      * returns the resultant vnode in a vpp argument.
   1542      */
   1543 
   1544     MARK_ENTRY(CODA_SYMLINK_STATS);
   1545 
   1546     /* Check for symlink of control object. */
   1547     if (IS_CTL_NAME(dvp, nm, len)) {
   1548 	MARK_INT_FAIL(CODA_SYMLINK_STATS);
   1549 	error = EACCES;
   1550 	goto exit;
   1551     }
   1552 
   1553     if (plen+1 > CODA_MAXPATHLEN) {
   1554 	MARK_INT_FAIL(CODA_SYMLINK_STATS);
   1555 	error = EINVAL;
   1556 	goto exit;
   1557     }
   1558 
   1559     if (len+1 > CODA_MAXNAMLEN) {
   1560 	MARK_INT_FAIL(CODA_SYMLINK_STATS);
   1561 	error = EINVAL;
   1562 	goto exit;
   1563     }
   1564 
   1565     error = venus_symlink(vtomi(dvp), &dcp->c_fid, path, plen, nm, len, tva, cred, l);
   1566 
   1567     /* Invalidate the parent's attr cache (modification time has changed). */
   1568     dcp->c_flags &= ~C_VATTR;
   1569 
   1570     if (!error) {
   1571 	/*
   1572 	 * VOP_SYMLINK is not defined to pay attention to cnp->cn_flags;
   1573 	 * these are defined only for VOP_LOOKUP.   We desire to reuse
   1574 	 * cnp for a VOP_LOOKUP operation, and must be sure to not pass
   1575 	 * stray flags passed to us.  Such stray flags can occur because
   1576 	 * sys_symlink makes a namei call and then reuses the
   1577 	 * componentname structure.
   1578 	 */
   1579 	/*
   1580 	 * XXX Arguably we should create our own componentname structure
   1581 	 * and not reuse the one that was passed in.
   1582 	 */
   1583 	saved_cn_flags = cnp->cn_flags;
   1584 	cnp->cn_flags &= ~(MODMASK | OPMASK);
   1585 	cnp->cn_flags |= LOOKUP;
   1586 	error = VOP_LOOKUP(dvp, ap->a_vpp, cnp);
   1587 	cnp->cn_flags = saved_cn_flags;
   1588 	/* Either an error occurs, or ap->a_vpp is locked. */
   1589     }
   1590 
   1591  exit:
   1592     /* unlock and deference parent */
   1593     vput(dvp);
   1594 
   1595     CODADEBUG(CODA_SYMLINK, myprintf(("in symlink result %d\n",error)); )
   1596     return(error);
   1597 }
   1598 
   1599 /*
   1600  * Read directory entries.
   1601  */
   1602 int
   1603 coda_readdir(void *v)
   1604 {
   1605 /* true args */
   1606     struct vop_readdir_args *ap = v;
   1607     struct vnode *vp = ap->a_vp;
   1608     struct cnode *cp = VTOC(vp);
   1609     struct uio *uiop = ap->a_uio;
   1610     kauth_cred_t cred = ap->a_cred;
   1611     int *eofflag = ap->a_eofflag;
   1612     off_t **cookies = ap->a_cookies;
   1613     int *ncookies = ap->a_ncookies;
   1614 /* upcall decl */
   1615 /* locals */
   1616     int error = 0;
   1617 
   1618     MARK_ENTRY(CODA_READDIR_STATS);
   1619 
   1620     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)); )
   1621 
   1622     /* Check for readdir of control object. */
   1623     if (IS_CTL_VP(vp)) {
   1624 	MARK_INT_FAIL(CODA_READDIR_STATS);
   1625 	return(ENOENT);
   1626     }
   1627 
   1628     {
   1629 	/* Redirect the request to UFS. */
   1630 
   1631 	/* If directory is not already open do an "internal open" on it. */
   1632 	int opened_internally = 0;
   1633 	if (cp->c_ovp == NULL) {
   1634 	    opened_internally = 1;
   1635 	    MARK_INT_GEN(CODA_OPEN_STATS);
   1636 	    error = VOP_OPEN(vp, FREAD, cred);
   1637 #ifdef	CODA_VERBOSE
   1638 printf("coda_readdir: Internally Opening %p\n", vp);
   1639 #endif
   1640 	    if (error) return(error);
   1641 	} else
   1642 	    vp = cp->c_ovp;
   1643 
   1644 	/* Have UFS handle the call. */
   1645 	CODADEBUG(CODA_READDIR, myprintf((
   1646 				"indirect readdir: fid = %s, refcnt = %d\n",
   1647 				coda_f2s(&cp->c_fid), vp->v_usecount)); )
   1648 	error = VOP_READDIR(vp, uiop, cred, eofflag, cookies, ncookies);
   1649 	if (error)
   1650 	    MARK_INT_FAIL(CODA_READDIR_STATS);
   1651 	else
   1652 	    MARK_INT_SAT(CODA_READDIR_STATS);
   1653 
   1654 	/* Do an "internal close" if necessary. */
   1655 	if (opened_internally) {
   1656 	    MARK_INT_GEN(CODA_CLOSE_STATS);
   1657 	    (void)VOP_CLOSE(vp, FREAD, cred);
   1658 	}
   1659     }
   1660 
   1661     return(error);
   1662 }
   1663 
   1664 /*
   1665  * Convert from file system blocks to device blocks
   1666  */
   1667 int
   1668 coda_bmap(void *v)
   1669 {
   1670     /* XXX on the global proc */
   1671 /* true args */
   1672     struct vop_bmap_args *ap = v;
   1673     struct vnode *vp __unused = ap->a_vp;	/* file's vnode */
   1674     daddr_t bn __unused = ap->a_bn;	/* fs block number */
   1675     struct vnode **vpp = ap->a_vpp;			/* RETURN vp of device */
   1676     daddr_t *bnp __unused = ap->a_bnp;	/* RETURN device block number */
   1677     struct lwp *l __unused = curlwp;
   1678 /* upcall decl */
   1679 /* locals */
   1680 
   1681 	*vpp = (struct vnode *)0;
   1682 	myprintf(("coda_bmap called!\n"));
   1683 	return(EINVAL);
   1684 }
   1685 
   1686 /*
   1687  * I don't think the following two things are used anywhere, so I've
   1688  * commented them out
   1689  *
   1690  * struct buf *async_bufhead;
   1691  * int async_daemon_count;
   1692  */
   1693 int
   1694 coda_strategy(void *v)
   1695 {
   1696 /* true args */
   1697     struct vop_strategy_args *ap = v;
   1698     struct buf *bp __unused = ap->a_bp;
   1699     struct lwp *l __unused = curlwp;
   1700 /* upcall decl */
   1701 /* locals */
   1702 
   1703 	myprintf(("coda_strategy called!  "));
   1704 	return(EINVAL);
   1705 }
   1706 
   1707 int
   1708 coda_reclaim(void *v)
   1709 {
   1710 /* true args */
   1711     struct vop_reclaim_args *ap = v;
   1712     struct vnode *vp = ap->a_vp;
   1713     struct cnode *cp = VTOC(vp);
   1714 /* upcall decl */
   1715 /* locals */
   1716 
   1717 /*
   1718  * Forced unmount/flush will let vnodes with non zero use be destroyed!
   1719  */
   1720     ENTRY;
   1721 
   1722     if (IS_UNMOUNTING(cp)) {
   1723 #ifdef	DEBUG
   1724 	if (VTOC(vp)->c_ovp) {
   1725 	    if (IS_UNMOUNTING(cp))
   1726 		printf("coda_reclaim: c_ovp not void: vp %p, cp %p\n", vp, cp);
   1727 	}
   1728 #endif
   1729     } else {
   1730 #ifdef OLD_DIAGNOSTIC
   1731 	if (vp->v_usecount != 0)
   1732 	    print("coda_reclaim: pushing active %p\n", vp);
   1733 	if (VTOC(vp)->c_ovp) {
   1734 	    panic("coda_reclaim: c_ovp not void");
   1735 	}
   1736 #endif
   1737     }
   1738     coda_free(VTOC(vp));
   1739     SET_VTOC(vp) = NULL;
   1740     return (0);
   1741 }
   1742 
   1743 int
   1744 coda_lock(void *v)
   1745 {
   1746 /* true args */
   1747     struct vop_lock_args *ap = v;
   1748     struct vnode *vp = ap->a_vp;
   1749     struct cnode *cp = VTOC(vp);
   1750 /* upcall decl */
   1751 /* locals */
   1752 
   1753     ENTRY;
   1754 
   1755     if (coda_lockdebug) {
   1756 	myprintf(("Attempting lock on %s\n",
   1757 		  coda_f2s(&cp->c_fid)));
   1758     }
   1759 
   1760     return genfs_lock(v);
   1761 }
   1762 
   1763 int
   1764 coda_unlock(void *v)
   1765 {
   1766 /* true args */
   1767     struct vop_unlock_args *ap = v;
   1768     struct vnode *vp = ap->a_vp;
   1769     struct cnode *cp = VTOC(vp);
   1770 /* upcall decl */
   1771 /* locals */
   1772 
   1773     ENTRY;
   1774     if (coda_lockdebug) {
   1775 	myprintf(("Attempting unlock on %s\n",
   1776 		  coda_f2s(&cp->c_fid)));
   1777     }
   1778 
   1779     return genfs_unlock(v);
   1780 }
   1781 
   1782 int
   1783 coda_islocked(void *v)
   1784 {
   1785 /* true args */
   1786     ENTRY;
   1787 
   1788     return genfs_islocked(v);
   1789 }
   1790 
   1791 /*
   1792  * Given a device and inode, obtain a locked vnode.  One reference is
   1793  * obtained and passed back to the caller.
   1794  */
   1795 int
   1796 coda_grab_vnode(dev_t dev, ino_t ino, struct vnode **vpp)
   1797 {
   1798     int           error;
   1799     struct mount *mp;
   1800 
   1801     /* Obtain mount point structure from device. */
   1802     if (!(mp = devtomp(dev))) {
   1803 	myprintf(("coda_grab_vnode: devtomp(0x%llx) returns NULL\n",
   1804 	    (unsigned long long)dev));
   1805 	return(ENXIO);
   1806     }
   1807 
   1808     /*
   1809      * Obtain vnode from mount point and inode.
   1810      * XXX VFS_VGET does not clearly define locked/referenced state of
   1811      * returned vnode.
   1812      */
   1813     error = VFS_VGET(mp, ino, vpp);
   1814     if (error) {
   1815 	myprintf(("coda_grab_vnode: iget/vget(0x%llx, %llu) returns %p, err %d\n",
   1816 	    (unsigned long long)dev, (unsigned long long)ino, *vpp, error));
   1817 	return(ENOENT);
   1818     }
   1819     return(0);
   1820 }
   1821 
   1822 void
   1823 print_vattr(struct vattr *attr)
   1824 {
   1825     const char *typestr;
   1826 
   1827     switch (attr->va_type) {
   1828     case VNON:
   1829 	typestr = "VNON";
   1830 	break;
   1831     case VREG:
   1832 	typestr = "VREG";
   1833 	break;
   1834     case VDIR:
   1835 	typestr = "VDIR";
   1836 	break;
   1837     case VBLK:
   1838 	typestr = "VBLK";
   1839 	break;
   1840     case VCHR:
   1841 	typestr = "VCHR";
   1842 	break;
   1843     case VLNK:
   1844 	typestr = "VLNK";
   1845 	break;
   1846     case VSOCK:
   1847 	typestr = "VSCK";
   1848 	break;
   1849     case VFIFO:
   1850 	typestr = "VFFO";
   1851 	break;
   1852     case VBAD:
   1853 	typestr = "VBAD";
   1854 	break;
   1855     default:
   1856 	typestr = "????";
   1857 	break;
   1858     }
   1859 
   1860 
   1861     myprintf(("attr: type %s mode %d uid %d gid %d fsid %d rdev %d\n",
   1862 	      typestr, (int)attr->va_mode, (int)attr->va_uid,
   1863 	      (int)attr->va_gid, (int)attr->va_fsid, (int)attr->va_rdev));
   1864 
   1865     myprintf(("      fileid %d nlink %d size %d blocksize %d bytes %d\n",
   1866 	      (int)attr->va_fileid, (int)attr->va_nlink,
   1867 	      (int)attr->va_size,
   1868 	      (int)attr->va_blocksize,(int)attr->va_bytes));
   1869     myprintf(("      gen %ld flags %ld vaflags %d\n",
   1870 	      attr->va_gen, attr->va_flags, attr->va_vaflags));
   1871     myprintf(("      atime sec %d nsec %d\n",
   1872 	      (int)attr->va_atime.tv_sec, (int)attr->va_atime.tv_nsec));
   1873     myprintf(("      mtime sec %d nsec %d\n",
   1874 	      (int)attr->va_mtime.tv_sec, (int)attr->va_mtime.tv_nsec));
   1875     myprintf(("      ctime sec %d nsec %d\n",
   1876 	      (int)attr->va_ctime.tv_sec, (int)attr->va_ctime.tv_nsec));
   1877 }
   1878 
   1879 /* How to print a ucred */
   1880 void
   1881 print_cred(kauth_cred_t cred)
   1882 {
   1883 
   1884 	uint16_t ngroups;
   1885 	int i;
   1886 
   1887 	myprintf(("ref %d\tuid %d\n", kauth_cred_getrefcnt(cred),
   1888 		 kauth_cred_geteuid(cred)));
   1889 
   1890 	ngroups = kauth_cred_ngroups(cred);
   1891 	for (i=0; i < ngroups; i++)
   1892 		myprintf(("\tgroup %d: (%d)\n", i, kauth_cred_group(cred, i)));
   1893 	myprintf(("\n"));
   1894 
   1895 }
   1896 
   1897 /*
   1898  * Return a vnode for the given fid.
   1899  * If no cnode exists for this fid create one and put it
   1900  * in a table hashed by coda_f2i().  If the cnode for
   1901  * this fid is already in the table return it (ref count is
   1902  * incremented by coda_find.  The cnode will be flushed from the
   1903  * table when coda_inactive calls coda_unsave.
   1904  */
   1905 struct cnode *
   1906 make_coda_node(CodaFid *fid, struct mount *vfsp, short type)
   1907 {
   1908     struct cnode *cp;
   1909     int          err;
   1910 
   1911     if ((cp = coda_find(fid)) == NULL) {
   1912 	struct vnode *vp;
   1913 
   1914 	cp = coda_alloc();
   1915 	cp->c_fid = *fid;
   1916 
   1917 	err = getnewvnode(VT_CODA, vfsp, coda_vnodeop_p, NULL, &vp);
   1918 	if (err) {
   1919 	    panic("coda: getnewvnode returned error %d", err);
   1920 	}
   1921 	vp->v_data = cp;
   1922 	vp->v_type = type;
   1923 	cp->c_vnode = vp;
   1924 	uvm_vnp_setsize(vp, 0);
   1925 	coda_save(cp);
   1926 
   1927     } else {
   1928 	vref(CTOV(cp));
   1929     }
   1930 
   1931     return cp;
   1932 }
   1933 
   1934 /*
   1935  * coda_getpages may be called on a vnode which has not been opened,
   1936  * e.g. to fault in pages to execute a program.  In that case, we must
   1937  * open the file to get the container.  The vnode may or may not be
   1938  * locked, and we must leave it in the same state.
   1939  * XXX The protocol requires v_uobj.vmobjlock to be
   1940  * held by caller, but this isn't documented in vnodeops(9) or vnode_if.src.
   1941  */
   1942 int
   1943 coda_getpages(void *v)
   1944 {
   1945 	struct vop_getpages_args /* {
   1946 		struct vnode *a_vp;
   1947 		voff_t a_offset;
   1948 		struct vm_page **a_m;
   1949 		int *a_count;
   1950 		int a_centeridx;
   1951 		vm_prot_t a_access_type;
   1952 		int a_advice;
   1953 		int a_flags;
   1954 	} */ *ap = v;
   1955 	struct vnode *vp = ap->a_vp;
   1956 	struct cnode *cp = VTOC(vp);
   1957 	struct lwp *l = curlwp;
   1958 	kauth_cred_t cred = l->l_cred;
   1959 	int error, cerror;
   1960 	int waslocked;	       /* 1 if vnode lock was held on entry */
   1961 	int didopen = 0;	/* 1 if we opened container file */
   1962 
   1963 	/*
   1964 	 * Handle a case that uvm_fault doesn't quite use yet.
   1965 	 * See layer_vnops.c. for inspiration.
   1966 	 */
   1967 	if (ap->a_flags & PGO_LOCKED) {
   1968 		return EBUSY;
   1969 	}
   1970 
   1971 	/* Check for control object. */
   1972 	if (IS_CTL_VP(vp)) {
   1973 		printf("coda_getpages: control object %p\n", vp);
   1974 		mutex_exit(vp->v_uobj.vmobjlock);
   1975 		return(EINVAL);
   1976 	}
   1977 
   1978 	/*
   1979 	 * XXX It's really not ok to be releasing the lock we get,
   1980 	 * because we could be overlapping with another call to
   1981 	 * getpages and drop a lock they are relying on.  We need to
   1982 	 * figure out whether getpages ever is called holding the
   1983 	 * lock, and if we should serialize getpages calls by some
   1984 	 * mechanism.
   1985 	 */
   1986 	/* XXX VOP_ISLOCKED() may not be used for lock decisions. */
   1987 	waslocked = VOP_ISLOCKED(vp);
   1988 
   1989 	/* Drop the vmobject lock. */
   1990 	mutex_exit(vp->v_uobj.vmobjlock);
   1991 
   1992 	/* Get container file if not already present. */
   1993 	if (cp->c_ovp == NULL) {
   1994 		/*
   1995 		 * VOP_OPEN requires a locked vnode.  We must avoid
   1996 		 * locking the vnode if it is already locked, and
   1997 		 * leave it in the same state on exit.
   1998 		 */
   1999 		if (waslocked == 0) {
   2000 			cerror = vn_lock(vp, LK_EXCLUSIVE);
   2001 			if (cerror) {
   2002 				printf("coda_getpages: can't lock vnode %p\n",
   2003 				       vp);
   2004 				return cerror;
   2005 			}
   2006 #if 0
   2007 			printf("coda_getpages: locked vnode %p\n", vp);
   2008 #endif
   2009 		}
   2010 
   2011 		/*
   2012 		 * Open file (causes upcall to venus).
   2013 		 * XXX Perhaps we should not fully open the file, but
   2014 		 * simply obtain a container file.
   2015 		 */
   2016 		/* XXX Is it ok to do this while holding the simplelock? */
   2017 		cerror = VOP_OPEN(vp, FREAD, cred);
   2018 
   2019 		if (cerror) {
   2020 			printf("coda_getpages: cannot open vnode %p => %d\n",
   2021 			       vp, cerror);
   2022 			if (waslocked == 0)
   2023 				VOP_UNLOCK(vp);
   2024 			return cerror;
   2025 		}
   2026 
   2027 #if 0
   2028 		printf("coda_getpages: opened vnode %p\n", vp);
   2029 #endif
   2030 		didopen = 1;
   2031 	}
   2032 	KASSERT(cp->c_ovp != NULL);
   2033 
   2034 	/* Munge the arg structure to refer to the container vnode. */
   2035 	ap->a_vp = cp->c_ovp;
   2036 
   2037 	/* Get the lock on the container vnode, and call getpages on it. */
   2038 	mutex_enter(ap->a_vp->v_uobj.vmobjlock);
   2039 	error = VCALL(ap->a_vp, VOFFSET(vop_getpages), ap);
   2040 
   2041 	/* If we opened the vnode, we must close it. */
   2042 	if (didopen) {
   2043 		/*
   2044 		 * VOP_CLOSE requires a locked vnode, but we are still
   2045 		 * holding the lock (or riding a caller's lock).
   2046 		 */
   2047 		cerror = VOP_CLOSE(vp, FREAD, cred);
   2048 		if (cerror != 0)
   2049 			/* XXX How should we handle this? */
   2050 			printf("coda_getpages: closed vnode %p -> %d\n",
   2051 			       vp, cerror);
   2052 
   2053 		/* If we obtained a lock, drop it. */
   2054 		if (waslocked == 0)
   2055 			VOP_UNLOCK(vp);
   2056 	}
   2057 
   2058 	return error;
   2059 }
   2060 
   2061 /*
   2062  * The protocol requires v_uobj.vmobjlock to be held by the caller, as
   2063  * documented in vnodeops(9).  XXX vnode_if.src doesn't say this.
   2064  */
   2065 int
   2066 coda_putpages(void *v)
   2067 {
   2068 	struct vop_putpages_args /* {
   2069 		struct vnode *a_vp;
   2070 		voff_t a_offlo;
   2071 		voff_t a_offhi;
   2072 		int a_flags;
   2073 	} */ *ap = v;
   2074 	struct vnode *vp = ap->a_vp;
   2075 	struct cnode *cp = VTOC(vp);
   2076 	int error;
   2077 
   2078 	/* Drop the vmobject lock. */
   2079 	mutex_exit(vp->v_uobj.vmobjlock);
   2080 
   2081 	/* Check for control object. */
   2082 	if (IS_CTL_VP(vp)) {
   2083 		printf("coda_putpages: control object %p\n", vp);
   2084 		return(EINVAL);
   2085 	}
   2086 
   2087 	/*
   2088 	 * If container object is not present, then there are no pages
   2089 	 * to put; just return without error.  This happens all the
   2090 	 * time, apparently during discard of a closed vnode (which
   2091 	 * trivially can't have dirty pages).
   2092 	 */
   2093 	if (cp->c_ovp == NULL)
   2094 		return 0;
   2095 
   2096 	/* Munge the arg structure to refer to the container vnode. */
   2097 	ap->a_vp = cp->c_ovp;
   2098 
   2099 	/* Get the lock on the container vnode, and call putpages on it. */
   2100 	mutex_enter(ap->a_vp->v_uobj.vmobjlock);
   2101 	error = VCALL(ap->a_vp, VOFFSET(vop_putpages), ap);
   2102 
   2103 	return error;
   2104 }
   2105