Пример #1
0
/* question: does afs_create need to set CDirty in the adp or the avc?
 * I think we can get away without it, but I'm not sure.  Note that
 * afs_setattr is called in here for truncation.
 */
#ifdef AFS_SGI64_ENV
int
afs_create(OSI_VC_DECL(adp), char *aname, struct vattr *attrs, int flags,
	   int amode, struct vcache **avcp, afs_ucred_t *acred)
#else /* AFS_SGI64_ENV */
int
afs_create(OSI_VC_DECL(adp), char *aname, struct vattr *attrs,
	   enum vcexcl aexcl, int amode, struct vcache **avcp,
	   afs_ucred_t *acred)
#endif				/* AFS_SGI64_ENV */
{
    afs_int32 origCBs, origZaps, finalZaps;
    struct vrequest *treq = NULL;
    afs_int32 code;
    struct afs_conn *tc;
    struct VenusFid newFid;
    struct AFSStoreStatus InStatus;
    struct AFSFetchStatus *OutFidStatus, *OutDirStatus;
    struct AFSVolSync tsync;
    struct AFSCallBack CallBack;
    afs_int32 now;
    struct dcache *tdc;
    afs_size_t offset, len;
    struct server *hostp = 0;
    struct vcache *tvc;
    struct volume *volp = 0;
    struct afs_fakestat_state fakestate;
    struct rx_connection *rxconn;
    XSTATS_DECLS;
    OSI_VC_CONVERT(adp);

    AFS_STATCNT(afs_create);

    OutFidStatus = osi_AllocSmallSpace(sizeof(struct AFSFetchStatus));
    OutDirStatus = osi_AllocSmallSpace(sizeof(struct AFSFetchStatus));
    memset(&InStatus, 0, sizeof(InStatus));

    if ((code = afs_CreateReq(&treq, acred)))
	goto done2;

    afs_Trace3(afs_iclSetp, CM_TRACE_CREATE, ICL_TYPE_POINTER, adp,
	       ICL_TYPE_STRING, aname, ICL_TYPE_INT32, amode);

    afs_InitFakeStat(&fakestate);

#ifdef AFS_SGI65_ENV
    /* If avcp is passed not null, it's the old reference to this file.
     * We can use this to avoid create races. For now, just decrement
     * the reference count on it.
     */
    if (*avcp) {
	AFS_RELE(AFSTOV(*avcp));
	*avcp = NULL;
    }
#endif

    if (strlen(aname) > AFSNAMEMAX) {
	code = ENAMETOOLONG;
	goto done3;
    }

    if (!afs_ENameOK(aname)) {
	code = EINVAL;
	goto done3;
    }
    switch (attrs->va_type) {
    case VBLK:
    case VCHR:
#if	!defined(AFS_SUN5_ENV)
    case VSOCK:
#endif
    case VFIFO:
	/* We don't support special devices or FIFOs */
	code = EINVAL;
	goto done3;
    default:
	;
    }
    AFS_DISCON_LOCK();

    code = afs_EvalFakeStat(&adp, &fakestate, treq);
    if (code)
	goto done;
  tagain:
    code = afs_VerifyVCache(adp, treq);
    if (code)
	goto done;

    /** If the volume is read-only, return error without making an RPC to the
      * fileserver
      */
    if (adp->f.states & CRO) {
	code = EROFS;
	goto done;
    }

    if (AFS_IS_DISCONNECTED && !AFS_IS_DISCON_RW) {
        code = ENETDOWN;
        goto done;
    }

    tdc = afs_GetDCache(adp, (afs_size_t) 0, treq, &offset, &len, 1);
    ObtainWriteLock(&adp->lock, 135);
    if (tdc)
	ObtainSharedLock(&tdc->lock, 630);

    /*
     * Make sure that the data in the cache is current. We may have
     * received a callback while we were waiting for the write lock.
     */
    if (!(adp->f.states & CStatd)
	|| (tdc && !hsame(adp->f.m.DataVersion, tdc->f.versionNo))) {
	ReleaseWriteLock(&adp->lock);
	if (tdc) {
	    ReleaseSharedLock(&tdc->lock);
	    afs_PutDCache(tdc);
	}
	goto tagain;
    }
    if (tdc) {
	/* see if file already exists.  If it does, we only set 
	 * the size attributes (to handle O_TRUNC) */
	code = afs_dir_Lookup(tdc, aname, &newFid.Fid);	/* use dnlc first xxx */
	if (code == 0) {
	    ReleaseSharedLock(&tdc->lock);
	    afs_PutDCache(tdc);
	    ReleaseWriteLock(&adp->lock);
#ifdef AFS_SGI64_ENV
	    if (flags & VEXCL) {
#else
	    if (aexcl != NONEXCL) {
#endif
		code = EEXIST;	/* file exists in excl mode open */
		goto done;
	    }
	    /* found the file, so use it */
	    newFid.Cell = adp->f.fid.Cell;
	    newFid.Fid.Volume = adp->f.fid.Fid.Volume;
	    tvc = NULL;
	    if (newFid.Fid.Unique == 0) {
		tvc = afs_LookupVCache(&newFid, treq, NULL, adp, aname);
	    }
	    if (!tvc)		/* lookup failed or wasn't called */
		tvc = afs_GetVCache(&newFid, treq, NULL, NULL);

	    if (tvc) {
		/* if the thing exists, we need the right access to open it.
		 * we must check that here, since no other checks are
		 * made by the open system call */
		len = attrs->va_size;	/* only do the truncate */
		/*
		 * We used to check always for READ access before; the
		 * problem is that we will fail if the existing file
		 * has mode -w-w-w, which is wrong.
		 */
		if ((amode & VREAD)
		    && !afs_AccessOK(tvc, PRSFS_READ, treq, CHECK_MODE_BITS)) {
		    afs_PutVCache(tvc);
		    code = EACCES;
		    goto done;
		}
#if defined(AFS_DARWIN80_ENV)
		if ((amode & VWRITE) || VATTR_IS_ACTIVE(attrs, va_data_size))
#elif defined(AFS_SUN5_ENV) || defined(AFS_SGI_ENV)
		if ((amode & VWRITE) || (attrs->va_mask & AT_SIZE))
#else
		if ((amode & VWRITE) || len != 0xffffffff)
#endif
		{
		    /* needed for write access check */
		    tvc->f.parent.vnode = adp->f.fid.Fid.Vnode;
		    tvc->f.parent.unique = adp->f.fid.Fid.Unique;
		    /* need write mode for these guys */
		    if (!afs_AccessOK
			(tvc, PRSFS_WRITE, treq, CHECK_MODE_BITS)) {
			afs_PutVCache(tvc);
			code = EACCES;
			goto done;
		    }
		}
#if defined(AFS_DARWIN80_ENV)
		if (VATTR_IS_ACTIVE(attrs, va_data_size))
#elif defined(AFS_SUN5_ENV) || defined(AFS_SGI_ENV)
		if (attrs->va_mask & AT_SIZE)
#else
		if (len != 0xffffffff)
#endif
		{
		    if (vType(tvc) != VREG) {
			afs_PutVCache(tvc);
			code = EISDIR;
			goto done;
		    }
		    /* do a truncate */
#if defined(AFS_DARWIN80_ENV)
		    VATTR_INIT(attrs);
		    VATTR_SET_SUPPORTED(attrs, va_data_size);
		    VATTR_SET_ACTIVE(attrs, va_data_size);
#elif defined(UKERNEL)
		    attrs->va_mask = ATTR_SIZE;
#elif defined(AFS_SUN5_ENV) || defined(AFS_SGI_ENV)
		    attrs->va_mask = AT_SIZE;
#else
		    VATTR_NULL(attrs);
#endif
		    attrs->va_size = len;
		    ObtainWriteLock(&tvc->lock, 136);
		    tvc->f.states |= CCreating;
		    ReleaseWriteLock(&tvc->lock);
#if defined(AFS_SUN5_ENV) || defined(AFS_SGI_ENV)
#if defined(AFS_SGI64_ENV)
		    code =
			afs_setattr(VNODE_TO_FIRST_BHV((vnode_t *) tvc),
				    attrs, 0, acred);
#else
		    code = afs_setattr(tvc, attrs, 0, acred);
#endif /* AFS_SGI64_ENV */
#else /* SUN5 || SGI */
		    code = afs_setattr(tvc, attrs, acred);
#endif /* SUN5 || SGI */
		    ObtainWriteLock(&tvc->lock, 137);
		    tvc->f.states &= ~CCreating;
		    ReleaseWriteLock(&tvc->lock);
		    if (code) {
			afs_PutVCache(tvc);
			goto done;
		    }
		}
		*avcp = tvc;
	    } else
		code = ENOENT;	/* shouldn't get here */
	    /* make sure vrefCount bumped only if code == 0 */
	    goto done;
	}
    }
    
    /* if we create the file, we don't do any access checks, since
     * that's how O_CREAT is supposed to work */
    if (adp->f.states & CForeign) {
	origCBs = afs_allCBs;
	origZaps = afs_allZaps;
    } else {
	origCBs = afs_evenCBs;	/* if changes, we don't really have a callback */
	origZaps = afs_evenZaps;	/* number of even numbered vnodes discarded */
    }
    InStatus.Mask = AFS_SETMODTIME | AFS_SETMODE | AFS_SETGROUP;
    InStatus.ClientModTime = osi_Time();
    InStatus.Group = (afs_int32) afs_cr_gid(acred);
    if (AFS_NFSXLATORREQ(acred)) {
	/*
	 * XXX The following is mainly used to fix a bug in the HP-UX
	 * nfs client where they create files with mode of 0 without
	 * doing any setattr later on to fix it.  * XXX
	 */
#if	defined(AFS_AIX_ENV)
	if (attrs->va_mode != -1) {
#else
#if	defined(AFS_SUN5_ENV) || defined(AFS_SGI_ENV)
	if (attrs->va_mask & AT_MODE) {
#else
	if (attrs->va_mode != ((unsigned short)-1)) {
#endif
#endif
	    if (!attrs->va_mode)
		attrs->va_mode = 0x1b6;	/* XXX default mode: rw-rw-rw XXX */
	}
    }

    if (!AFS_IS_DISCONNECTED) {
	/* If not disconnected, connect to the server.*/

    	InStatus.UnixModeBits = attrs->va_mode & 0xffff;	/* only care about protection bits */
    	do {
	    tc = afs_Conn(&adp->f.fid, treq, SHARED_LOCK, &rxconn);
	    if (tc) {
	    	hostp = tc->srvr->server;	/* remember for callback processing */
	    	now = osi_Time();
	    	XSTATS_START_TIME(AFS_STATS_FS_RPCIDX_CREATEFILE);
	    	RX_AFS_GUNLOCK();
	    	code =
		    RXAFS_CreateFile(rxconn, (struct AFSFid *)&adp->f.fid.Fid,
				 aname, &InStatus, (struct AFSFid *)
				 &newFid.Fid, OutFidStatus, OutDirStatus,
				 &CallBack, &tsync);
	    	RX_AFS_GLOCK();
	    	XSTATS_END_TIME;
	    	CallBack.ExpirationTime += now;
	    } else
	    	code = -1;
    	} while (afs_Analyze
	         (tc, rxconn, code, &adp->f.fid, treq, AFS_STATS_FS_RPCIDX_CREATEFILE,
	          SHARED_LOCK, NULL));

	if ((code == EEXIST || code == UAEEXIST) &&
#ifdef AFS_SGI64_ENV
    	!(flags & VEXCL)
#else /* AFS_SGI64_ENV */
    	aexcl == NONEXCL
#endif
    	) {
	    /* if we get an EEXIST in nonexcl mode, just do a lookup */
	    if (tdc) {
	    	ReleaseSharedLock(&tdc->lock);
	    	afs_PutDCache(tdc);
	    }
	    ReleaseWriteLock(&adp->lock);


#if defined(AFS_SGI64_ENV)
	    code = afs_lookup(VNODE_TO_FIRST_BHV((vnode_t *) adp), aname, avcp,
				  NULL, 0, NULL, acred);
#elif defined(AFS_SUN5_ENV) || defined(AFS_SGI_ENV)
	    code = afs_lookup(adp, aname, avcp, NULL, 0, NULL, acred);
#elif defined(UKERNEL)
	    code = afs_lookup(adp, aname, avcp, acred, 0);
#elif !defined(AFS_DARWIN_ENV)
	    code = afs_lookup(adp, aname, avcp, acred);
#endif
	goto done;
        }

	if (code) {
	    if (code < 0) {
	    	ObtainWriteLock(&afs_xcbhash, 488);
	    	afs_DequeueCallback(adp);
	    	adp->f.states &= ~CStatd;
	    	ReleaseWriteLock(&afs_xcbhash);
	    	osi_dnlc_purgedp(adp);
	    }
	    ReleaseWriteLock(&adp->lock);
	    if (tdc) {
	    	ReleaseSharedLock(&tdc->lock);
	    	afs_PutDCache(tdc);
	    }
	goto done;
	}

    } else {
	/* Generate a fake FID for disconnected mode. */
	newFid.Cell = adp->f.fid.Cell;
	newFid.Fid.Volume = adp->f.fid.Fid.Volume;
	afs_GenFakeFid(&newFid, VREG, 1);
    }				/* if (!AFS_IS_DISCON_RW) */

    /* otherwise, we should see if we can make the change to the dir locally */
    if (tdc)
	UpgradeSToWLock(&tdc->lock, 631);
    if (AFS_IS_DISCON_RW || afs_LocalHero(adp, tdc, OutDirStatus, 1)) {
	/* we can do it locally */
	ObtainWriteLock(&afs_xdcache, 291);
	code = afs_dir_Create(tdc, aname, &newFid.Fid);
	ReleaseWriteLock(&afs_xdcache);
	if (code) {
	    ZapDCE(tdc);
	    DZap(tdc);
	}
    }
    if (tdc) {
	ReleaseWriteLock(&tdc->lock);
	afs_PutDCache(tdc);
    }
    if (AFS_IS_DISCON_RW)
	adp->f.m.LinkCount++;

    newFid.Cell = adp->f.fid.Cell;
    newFid.Fid.Volume = adp->f.fid.Fid.Volume;
    ReleaseWriteLock(&adp->lock);
    volp = afs_FindVolume(&newFid, READ_LOCK);

    /* New tricky optimistic callback handling algorithm for file creation works
     * as follows.  We create the file essentially with no locks set at all.  File
     * server may thus handle operations from others cache managers as well as from
     * this very own cache manager that reference the file in question before
     * we managed to create the cache entry.  However, if anyone else changes
     * any of the status information for a file, we'll see afs_evenCBs increase
     * (files always have even fids).  If someone on this workstation manages
     * to do something to the file, they'll end up having to create a cache
     * entry for the new file.  Either we'll find it once we've got the afs_xvcache
     * lock set, or it was also *deleted* the vnode before we got there, in which case
     * we will find evenZaps has changed, too.  Thus, we only assume we have the right
     * status information if no callbacks or vnode removals have occurred to even
     * numbered files from the time the call started until the time that we got the xvcache
     * lock set.  Of course, this also assumes that any call that modifies a file first
     * gets a write lock on the file's vnode, but if that weren't true, the whole cache manager
     * would fail, since no call would be able to update the local vnode status after modifying
     * a file on a file server. */
    ObtainWriteLock(&afs_xvcache, 138);
    if (adp->f.states & CForeign)
	finalZaps = afs_allZaps;	/* do this before calling newvcache */
    else
	finalZaps = afs_evenZaps;	/* do this before calling newvcache */
    /* don't need to call RemoveVCB, since only path leaving a callback is the
     * one where we pass through afs_NewVCache.  Can't have queued a VCB unless
     * we created and freed an entry between file creation time and here, and the
     * freeing of the vnode will change evenZaps.  Don't need to update the VLRU
     * queue, since the find will only succeed in the event of a create race, and 
     * then the vcache will be at the front of the VLRU queue anyway...  */
    if (!(tvc = afs_FindVCache(&newFid, 0, DO_STATS))) {
	tvc = afs_NewVCache(&newFid, hostp);
	if (tvc) {
	    int finalCBs;
	    ObtainWriteLock(&tvc->lock, 139);

	    ObtainWriteLock(&afs_xcbhash, 489);
	    finalCBs = afs_evenCBs;
	    /* add the callback in */
	    if (adp->f.states & CForeign) {
		tvc->f.states |= CForeign;
		finalCBs = afs_allCBs;
	    }
	    if (origCBs == finalCBs && origZaps == finalZaps) {
		tvc->f.states |= CStatd;	/* we've fake entire thing, so don't stat */
		tvc->f.states &= ~CBulkFetching;
		if (!AFS_IS_DISCON_RW) {
		    tvc->cbExpires = CallBack.ExpirationTime;
		    afs_QueueCallback(tvc, CBHash(CallBack.ExpirationTime), volp);
		}
	    } else {
		afs_DequeueCallback(tvc);
		tvc->f.states &= ~(CStatd | CUnique);
		tvc->callback = 0;
		if (tvc->f.fid.Fid.Vnode & 1 || (vType(tvc) == VDIR))
		    osi_dnlc_purgedp(tvc);
	    }
	    ReleaseWriteLock(&afs_xcbhash);
	    if (AFS_IS_DISCON_RW) {
		afs_DisconAddDirty(tvc, VDisconCreate, 0);
		afs_GenDisconStatus(adp, tvc, &newFid, attrs, treq, VREG);
	    } else {
		afs_ProcessFS(tvc, OutFidStatus, treq);
	    }

	    tvc->f.parent.vnode = adp->f.fid.Fid.Vnode;
	    tvc->f.parent.unique = adp->f.fid.Fid.Unique;
#if !defined(UKERNEL)
            if (volp && (volp->states & VPartVisible))
                tvc->f.states |= CPartVisible;
#endif
	    ReleaseWriteLock(&tvc->lock);
	    *avcp = tvc;
	    code = 0;
	} else
	    code = ENOENT;
    } else {
	/* otherwise cache entry already exists, someone else must
	 * have created it.  Comments used to say:  "don't need write
	 * lock to *clear* these flags" but we should do it anyway.
	 * Code used to clear stat bit and callback, but I don't see 
	 * the point -- we didn't have a create race, somebody else just
	 * snuck into NewVCache before we got here, probably a racing 
	 * lookup.
	 */
	*avcp = tvc;
	code = 0;
    }
    ReleaseWriteLock(&afs_xvcache);

  done:
    AFS_DISCON_UNLOCK();

  done3:
    if (volp)
	afs_PutVolume(volp, READ_LOCK);

    if (code == 0) {
	if (afs_mariner)
	    afs_AddMarinerName(aname, *avcp);
	/* return the new status in vattr */
	afs_CopyOutAttrs(*avcp, attrs);
	if (afs_mariner)
	    afs_MarinerLog("store$Creating", *avcp);
    }

    afs_PutFakeStat(&fakestate);
    code = afs_CheckCode(code, treq, 20);
    afs_DestroyReq(treq);

  done2:
    osi_FreeSmallSpace(OutFidStatus);
    osi_FreeSmallSpace(OutDirStatus);
    return code;
}


/*
 * Check to see if we can track the change locally: requires that
 * we have sufficiently recent info in data cache.  If so, we
 * know the new DataVersion number, and place it correctly in both the
 * data and stat cache entries.  This routine returns 1 if we should
 * do the operation locally, and 0 otherwise.
 *
 * This routine must be called with the stat cache entry write-locked,
 * and dcache entry write-locked.
 */
int
afs_LocalHero(struct vcache *avc, struct dcache *adc,
	      AFSFetchStatus * astat, int aincr)
{
    afs_int32 ok;
    afs_hyper_t avers;

    AFS_STATCNT(afs_LocalHero);
    hset64(avers, astat->dataVersionHigh, astat->DataVersion);
    /* avers *is* the version number now, no matter what */

    if (adc) {
	/* does what's in the dcache *now* match what's in the vcache *now*,
	 * and do we have a valid callback? if not, our local copy is not "ok" */
	ok = (hsame(avc->f.m.DataVersion, adc->f.versionNo) && avc->callback
	      && (avc->f.states & CStatd) && avc->cbExpires >= osi_Time());
    } else {
	ok = 0;
    }
    if (ok) {
	/* check that the DV on the server is what we expect it to be */
	afs_hyper_t newDV;
	hset(newDV, adc->f.versionNo);
	hadd32(newDV, aincr);
	if (!hsame(avers, newDV)) {
	    ok = 0;
	}
    }
#if defined(AFS_SGI_ENV)
    osi_Assert(avc->v.v_type == VDIR);
#endif
    /* The bulk status code used the length as a sequence number.  */
    /* Don't update the vcache entry unless the stats are current. */
    if (avc->f.states & CStatd) {
	hset(avc->f.m.DataVersion, avers);
#ifdef AFS_64BIT_CLIENT
	FillInt64(avc->f.m.Length, astat->Length_hi, astat->Length);
#else /* AFS_64BIT_CLIENT */
	avc->f.m.Length = astat->Length;
#endif /* AFS_64BIT_CLIENT */
	avc->f.m.Date = astat->ClientModTime;
    }
    if (ok) {
	/* we've been tracking things correctly */
	adc->dflags |= DFEntryMod;
	adc->f.versionNo = avers;
	return 1;
    } else {
	if (adc) {
	    ZapDCE(adc);
	    DZap(adc);
	}
	if (avc->f.states & CStatd) {
	    osi_dnlc_purgedp(avc);
	}
	return 0;
    }
}
Пример #2
0
kern_return_t
map_fd_funneled(
	int			fd,
	vm_object_offset_t	offset,
	vm_offset_t		*va,
	boolean_t		findspace,
	vm_size_t		size)
{
	kern_return_t	result;
	struct fileproc	*fp;
	struct vnode	*vp;
	void *	pager;
	vm_offset_t	map_addr=0;
	vm_size_t	map_size;
	int		err=0;
	vm_map_t	my_map;
	proc_t		p = current_proc();
	struct vnode_attr vattr;

	/*
	 *	Find the inode; verify that it's a regular file.
	 */

	err = fp_lookup(p, fd, &fp, 0);
	if (err)
		return(err);
	
	if (fp->f_fglob->fg_type != DTYPE_VNODE){
		err = KERN_INVALID_ARGUMENT;
		goto bad;
	}

	if (!(fp->f_fglob->fg_flag & FREAD)) {
		err = KERN_PROTECTION_FAILURE;
		goto bad;
	}

	vp = (struct vnode *)fp->f_fglob->fg_data;
	err = vnode_getwithref(vp);
	if(err != 0) 
		goto bad;

	if (vp->v_type != VREG) {
		(void)vnode_put(vp);
		err = KERN_INVALID_ARGUMENT;
		goto bad;
	}

	AUDIT_ARG(vnpath, vp, ARG_VNODE1);

	/*
	 * POSIX: mmap needs to update access time for mapped files
	 */
	if ((vnode_vfsvisflags(vp) & MNT_NOATIME) == 0) {
		VATTR_INIT(&vattr);
		nanotime(&vattr.va_access_time);
		VATTR_SET_ACTIVE(&vattr, va_access_time);
		vnode_setattr(vp, &vattr, vfs_context_current());
	}
	
	if (offset & PAGE_MASK_64) {
		printf("map_fd: file offset not page aligned(%d : %s)\n",p->p_pid, p->p_comm);
		(void)vnode_put(vp);
		err = KERN_INVALID_ARGUMENT;
		goto bad;
	}
	map_size = round_page(size);

	/*
	 * Allow user to map in a zero length file.
	 */
	if (size == 0) {
		(void)vnode_put(vp);
		err = KERN_SUCCESS;
		goto bad;
	}
	/*
	 *	Map in the file.
	 */
	pager = (void *)ubc_getpager(vp);
	if (pager == NULL) {
		(void)vnode_put(vp);
		err = KERN_FAILURE;
		goto bad;
	}


	my_map = current_map();

	result = vm_map_64(
			my_map,
			&map_addr, map_size, (vm_offset_t)0, 
			VM_FLAGS_ANYWHERE, pager, offset, TRUE,
			VM_PROT_DEFAULT, VM_PROT_ALL,
			VM_INHERIT_DEFAULT);
	if (result != KERN_SUCCESS) {
		(void)vnode_put(vp);
		err = result;
		goto bad;
	}


	if (!findspace) {
		vm_offset_t	dst_addr;
		vm_map_copy_t	tmp;

		if (copyin(CAST_USER_ADDR_T(va), &dst_addr, sizeof (dst_addr))	||
					trunc_page_32(dst_addr) != dst_addr) {
			(void) vm_map_remove(
					my_map,
					map_addr, map_addr + map_size,
					VM_MAP_NO_FLAGS);
			(void)vnode_put(vp);
			err = KERN_INVALID_ADDRESS;
			goto bad;
		}

		result = vm_map_copyin(my_map, (vm_map_address_t)map_addr,
				       (vm_map_size_t)map_size, TRUE, &tmp);
		if (result != KERN_SUCCESS) {
			
			(void) vm_map_remove(my_map, vm_map_trunc_page(map_addr),
					vm_map_round_page(map_addr + map_size),
					VM_MAP_NO_FLAGS);
			(void)vnode_put(vp);
			err = result;
			goto bad;
		}

		result = vm_map_copy_overwrite(my_map,
					(vm_map_address_t)dst_addr, tmp, FALSE);
		if (result != KERN_SUCCESS) {
			vm_map_copy_discard(tmp);
			(void)vnode_put(vp);
			err = result;
			goto bad;
		}
	} else {
		if (copyout(&map_addr, CAST_USER_ADDR_T(va), sizeof (map_addr))) {
			(void) vm_map_remove(my_map, vm_map_trunc_page(map_addr),
					vm_map_round_page(map_addr + map_size),
					VM_MAP_NO_FLAGS);
			(void)vnode_put(vp);
			err = KERN_INVALID_ADDRESS;
			goto bad;
		}
	}

	ubc_setthreadcred(vp, current_proc(), current_thread());
	(void)ubc_map(vp, (PROT_READ | PROT_EXEC));
	(void)vnode_put(vp);
	err = 0;
bad:
	fp_drop(p, fd, fp, 0);
	return (err);
}
Пример #3
0
/*
 * XXX Internally, we use VM_PROT_* somewhat interchangeably, but the correct
 * XXX usage is PROT_* from an interface perspective.  Thus the values of
 * XXX VM_PROT_* and PROT_* need to correspond.
 */
int
mmap(proc_t p, struct mmap_args *uap, user_addr_t *retval)
{
	/*
	 *	Map in special device (must be SHARED) or file
	 */
	struct fileproc *fp;
	register struct		vnode *vp;
	int			flags;
	int			prot, file_prot;
	int			err=0;
	vm_map_t		user_map;
	kern_return_t		result;
	mach_vm_offset_t	user_addr;
	mach_vm_size_t		user_size;
	vm_object_offset_t	pageoff;
	vm_object_offset_t	file_pos;
	int			alloc_flags=0;
	boolean_t		docow;
	vm_prot_t		maxprot;
	void 			*handle;
	vm_pager_t		pager;
	int 			mapanon=0;
	int 			fpref=0;
	int error =0;
	int fd = uap->fd;

	user_addr = (mach_vm_offset_t)uap->addr;
	user_size = (mach_vm_size_t) uap->len;

	AUDIT_ARG(addr, user_addr);
	AUDIT_ARG(len, user_size);
	AUDIT_ARG(fd, uap->fd);

	prot = (uap->prot & VM_PROT_ALL);
#if 3777787
	/*
	 * Since the hardware currently does not support writing without
	 * read-before-write, or execution-without-read, if the request is
	 * for write or execute access, we must imply read access as well;
	 * otherwise programs expecting this to work will fail to operate.
	 */
	if (prot & (VM_PROT_EXECUTE | VM_PROT_WRITE))
		prot |= VM_PROT_READ;
#endif	/* radar 3777787 */

	flags = uap->flags;
	vp = NULLVP;

	/*
	 * The vm code does not have prototypes & compiler doesn't do the'
	 * the right thing when you cast 64bit value and pass it in function 
	 * call. So here it is.
	 */
	file_pos = (vm_object_offset_t)uap->pos;


	/* make sure mapping fits into numeric range etc */
	if (file_pos + user_size > (vm_object_offset_t)-PAGE_SIZE_64)
		return (EINVAL);

	/*
	 * Align the file position to a page boundary,
	 * and save its page offset component.
	 */
	pageoff = (file_pos & PAGE_MASK);
	file_pos -= (vm_object_offset_t)pageoff;


	/* Adjust size for rounding (on both ends). */
	user_size += pageoff;			/* low end... */
	user_size = mach_vm_round_page(user_size);	/* hi end */


	/*
	 * Check for illegal addresses.  Watch out for address wrap... Note
	 * that VM_*_ADDRESS are not constants due to casts (argh).
	 */
	if (flags & MAP_FIXED) {
		/*
		 * The specified address must have the same remainder
		 * as the file offset taken modulo PAGE_SIZE, so it
		 * should be aligned after adjustment by pageoff.
		 */
		user_addr -= pageoff;
		if (user_addr & PAGE_MASK)
		return (EINVAL);
	}
#ifdef notyet
	/* DO not have apis to get this info, need to wait till then*/
	/*
	 * XXX for non-fixed mappings where no hint is provided or
	 * the hint would fall in the potential heap space,
	 * place it after the end of the largest possible heap.
	 *
	 * There should really be a pmap call to determine a reasonable
	 * location.
	 */
	else if (addr < mach_vm_round_page(p->p_vmspace->vm_daddr + MAXDSIZ))
		addr = mach_vm_round_page(p->p_vmspace->vm_daddr + MAXDSIZ);

#endif

	alloc_flags = 0;

	if (flags & MAP_ANON) {
		/*
		 * Mapping blank space is trivial.  Use positive fds as the alias
		 * value for memory tracking. 
		 */
		if (fd != -1) {
			/*
			 * Use "fd" to pass (some) Mach VM allocation flags,
			 * (see the VM_FLAGS_* definitions).
			 */
			alloc_flags = fd & (VM_FLAGS_ALIAS_MASK |
					    VM_FLAGS_PURGABLE);
			if (alloc_flags != fd) {
				/* reject if there are any extra flags */
				return EINVAL;
			}
		}
			
		handle = NULL;
		maxprot = VM_PROT_ALL;
		file_pos = 0;
		mapanon = 1;
	} else {
		struct vnode_attr va;
		vfs_context_t ctx = vfs_context_current();

		/*
		 * Mapping file, get fp for validation. Obtain vnode and make
		 * sure it is of appropriate type.
		 */
		err = fp_lookup(p, fd, &fp, 0);
		if (err)
			return(err);
		fpref = 1;
		if(fp->f_fglob->fg_type == DTYPE_PSXSHM) {
			uap->addr = (user_addr_t)user_addr;
			uap->len = (user_size_t)user_size;
			uap->prot = prot;
			uap->flags = flags;
			uap->pos = file_pos;
			error = pshm_mmap(p, uap, retval, fp, (off_t)pageoff);
			goto bad;
		}

		if (fp->f_fglob->fg_type != DTYPE_VNODE) {
			error = EINVAL;
			goto bad;
		}
		vp = (struct vnode *)fp->f_fglob->fg_data;
		error = vnode_getwithref(vp);
		if(error != 0)
			goto bad;

		if (vp->v_type != VREG && vp->v_type != VCHR) {
			(void)vnode_put(vp);
			error = EINVAL;
			goto bad;
		}

		AUDIT_ARG(vnpath, vp, ARG_VNODE1);
		
		/*
		 * POSIX: mmap needs to update access time for mapped files
		 */
		if ((vnode_vfsvisflags(vp) & MNT_NOATIME) == 0) {
			VATTR_INIT(&va);
			nanotime(&va.va_access_time);
			VATTR_SET_ACTIVE(&va, va_access_time);
			vnode_setattr(vp, &va, ctx);
		}
		
		/*
		 * XXX hack to handle use of /dev/zero to map anon memory (ala
		 * SunOS).
		 */
		if (vp->v_type == VCHR || vp->v_type == VSTR) {
			(void)vnode_put(vp);
			error = ENODEV;
			goto bad;
		} else {
			/*
			 * Ensure that file and memory protections are
			 * compatible.  Note that we only worry about
			 * writability if mapping is shared; in this case,
			 * current and max prot are dictated by the open file.
			 * XXX use the vnode instead?  Problem is: what
			 * credentials do we use for determination? What if
			 * proc does a setuid?
			 */
			maxprot = VM_PROT_EXECUTE;	/* ??? */
			if (fp->f_fglob->fg_flag & FREAD)
				maxprot |= VM_PROT_READ;
			else if (prot & PROT_READ) {
				(void)vnode_put(vp);
				error = EACCES;
				goto bad;
			}
			/*
			 * If we are sharing potential changes (either via
			 * MAP_SHARED or via the implicit sharing of character
			 * device mappings), and we are trying to get write
			 * permission although we opened it without asking
			 * for it, bail out. 
			 */

			if ((flags & MAP_SHARED) != 0) {
				if ((fp->f_fglob->fg_flag & FWRITE) != 0) {
 					/*
 					 * check for write access
 					 *
 					 * Note that we already made this check when granting FWRITE
 					 * against the file, so it seems redundant here.
 					 */
 					error = vnode_authorize(vp, NULL, KAUTH_VNODE_CHECKIMMUTABLE, ctx);
 
 					/* if not granted for any reason, but we wanted it, bad */
 					if ((prot & PROT_WRITE) && (error != 0)) {
 						vnode_put(vp);
  						goto bad;
  					}
 
 					/* if writable, remember */
 					if (error == 0)
  						maxprot |= VM_PROT_WRITE;

				} else if ((prot & PROT_WRITE) != 0) {
					(void)vnode_put(vp);
					error = EACCES;
					goto bad;
				}
			} else
				maxprot |= VM_PROT_WRITE;

			handle = (void *)vp;
#if CONFIG_MACF
			error = mac_file_check_mmap(vfs_context_ucred(ctx),
			    fp->f_fglob, prot, flags, &maxprot);
			if (error) {
				(void)vnode_put(vp);
				goto bad;
			}
#endif /* MAC */
		}
	}

	if (user_size == 0)  {
		if (!mapanon)
			(void)vnode_put(vp);
		error = 0;
		goto bad;
	}

	/*
	 *	We bend a little - round the start and end addresses
	 *	to the nearest page boundary.
	 */
	user_size = mach_vm_round_page(user_size);

	if (file_pos & PAGE_MASK_64) {
		if (!mapanon)
			(void)vnode_put(vp);
		error = EINVAL;
		goto bad;
	}

	user_map = current_map();

	if ((flags & MAP_FIXED) == 0) {
		alloc_flags |= VM_FLAGS_ANYWHERE;
		user_addr = mach_vm_round_page(user_addr);
	} else {
		if (user_addr != mach_vm_trunc_page(user_addr)) {
		        if (!mapanon)
			        (void)vnode_put(vp);
			error = EINVAL;
			goto bad;
		}
		/*
		 * mmap(MAP_FIXED) will replace any existing mappings in the
		 * specified range, if the new mapping is successful.
		 * If we just deallocate the specified address range here,
		 * another thread might jump in and allocate memory in that
		 * range before we get a chance to establish the new mapping,
		 * and we won't have a chance to restore the old mappings.
		 * So we use VM_FLAGS_OVERWRITE to let Mach VM know that it
		 * has to deallocate the existing mappings and establish the
		 * new ones atomically.
		 */
		alloc_flags |= VM_FLAGS_FIXED | VM_FLAGS_OVERWRITE;
	}

	if (flags & MAP_NOCACHE)
		alloc_flags |= VM_FLAGS_NO_CACHE;

	/*
	 * Lookup/allocate object.
	 */
	if (handle == NULL) {
		pager = NULL;
#ifdef notyet
/* Hmm .. */
#if defined(VM_PROT_READ_IS_EXEC)
		if (prot & VM_PROT_READ)
			prot |= VM_PROT_EXECUTE;
		if (maxprot & VM_PROT_READ)
			maxprot |= VM_PROT_EXECUTE;
#endif
#endif

#if 3777787
		if (prot & (VM_PROT_EXECUTE | VM_PROT_WRITE))
			prot |= VM_PROT_READ;
		if (maxprot & (VM_PROT_EXECUTE | VM_PROT_WRITE))
			maxprot |= VM_PROT_READ;
#endif	/* radar 3777787 */

		result = vm_map_enter_mem_object(user_map,
						 &user_addr, user_size,
						 0, alloc_flags,
						 IPC_PORT_NULL, 0, FALSE,
						 prot, maxprot,
						 (flags & MAP_SHARED) ?
						 VM_INHERIT_SHARE : 
						 VM_INHERIT_DEFAULT);
		if (result != KERN_SUCCESS) 
				goto out;
	} else {
		pager = (vm_pager_t)ubc_getpager(vp);
		
		if (pager == NULL) {
			(void)vnode_put(vp);
			error = ENOMEM;
			goto bad;
		}

		/*
		 *  Set credentials:
		 *	FIXME: if we're writing the file we need a way to
		 *      ensure that someone doesn't replace our R/W creds
		 * 	with ones that only work for read.
		 */

		ubc_setthreadcred(vp, p, current_thread());
		docow = FALSE;
		if ((flags & (MAP_ANON|MAP_SHARED)) == 0) {
			docow = TRUE;
		}

#ifdef notyet
/* Hmm .. */
#if defined(VM_PROT_READ_IS_EXEC)
		if (prot & VM_PROT_READ)
			prot |= VM_PROT_EXECUTE;
		if (maxprot & VM_PROT_READ)
			maxprot |= VM_PROT_EXECUTE;
#endif
#endif /* notyet */

#if 3777787
		if (prot & (VM_PROT_EXECUTE | VM_PROT_WRITE))
			prot |= VM_PROT_READ;
		if (maxprot & (VM_PROT_EXECUTE | VM_PROT_WRITE))
			maxprot |= VM_PROT_READ;
#endif	/* radar 3777787 */

		result = vm_map_enter_mem_object(user_map,
						 &user_addr, user_size,
						 0, alloc_flags,
						 (ipc_port_t)pager, file_pos,
						 docow, prot, maxprot, 
						 (flags & MAP_SHARED) ?
						 VM_INHERIT_SHARE : 
						 VM_INHERIT_DEFAULT);

		if (result != KERN_SUCCESS)  {
				(void)vnode_put(vp);
				goto out;
		}

		file_prot = prot & (PROT_READ | PROT_WRITE | PROT_EXEC);
		if (docow) {
			/* private mapping: won't write to the file */
			file_prot &= ~PROT_WRITE;
		}
		(void) ubc_map(vp, file_prot);
	}

	if (!mapanon)
		(void)vnode_put(vp);

out:
	switch (result) {
	case KERN_SUCCESS:
		*retval = user_addr + pageoff;
		error = 0;
		break;
	case KERN_INVALID_ADDRESS:
	case KERN_NO_SPACE:
		error =  ENOMEM;
		break;
	case KERN_PROTECTION_FAILURE:
		error =  EACCES;
		break;
	default:
		error =  EINVAL;
		break;
	}
bad:
	if (fpref)
		fp_drop(p, fd, fp, 0);

	KERNEL_DEBUG_CONSTANT((BSDDBG_CODE(DBG_BSD_SC_EXTENDED_INFO, SYS_mmap) | DBG_FUNC_NONE), fd, (uint32_t)(*retval), (uint32_t)user_size, error, 0);
	KERNEL_DEBUG_CONSTANT((BSDDBG_CODE(DBG_BSD_SC_EXTENDED_INFO2, SYS_mmap) | DBG_FUNC_NONE), (uint32_t)(*retval >> 32), (uint32_t)(user_size >> 32),
			      (uint32_t)(file_pos >> 32), (uint32_t)file_pos, 0);

	return(error);
}
Пример #4
0
/*
 * shared_region_map_np()
 *
 * This system call is intended for dyld.
 *
 * dyld uses this to map a shared cache file into a shared region.
 * This is usually done only the first time a shared cache is needed.
 * Subsequent processes will just use the populated shared region without
 * requiring any further setup.
 */
int
shared_region_map_np(
	struct proc				*p,
	struct shared_region_map_np_args	*uap,
	__unused int				*retvalp)
{
	int				error;
	kern_return_t			kr;
	int				fd;
	struct fileproc			*fp;
	struct vnode			*vp, *root_vp;
	struct vnode_attr		va;
	off_t				fs;
	memory_object_size_t		file_size;
	user_addr_t			user_mappings;
	struct shared_file_mapping_np	*mappings;
#define SFM_MAX_STACK	8
	struct shared_file_mapping_np	stack_mappings[SFM_MAX_STACK];
	unsigned int			mappings_count;
	vm_size_t			mappings_size;
	memory_object_control_t		file_control;
	struct vm_shared_region		*shared_region;

	SHARED_REGION_TRACE_DEBUG(
		("shared_region: %p [%d(%s)] -> map\n",
		 current_thread(), p->p_pid, p->p_comm));

	shared_region = NULL;
	mappings_count = 0;
	mappings_size = 0;
	mappings = NULL;
	fp = NULL;
	vp = NULL;

	/* get file descriptor for shared region cache file */
	fd = uap->fd;

	/* get file structure from file descriptor */
	error = fp_lookup(p, fd, &fp, 0);
	if (error) {
		SHARED_REGION_TRACE_ERROR(
			("shared_region: %p [%d(%s)] map: "
			 "fd=%d lookup failed (error=%d)\n",
			 current_thread(), p->p_pid, p->p_comm, fd, error));
		goto done;
	}

	/* make sure we're attempting to map a vnode */
	if (fp->f_fglob->fg_type != DTYPE_VNODE) {
		SHARED_REGION_TRACE_ERROR(
			("shared_region: %p [%d(%s)] map: "
			 "fd=%d not a vnode (type=%d)\n",
			 current_thread(), p->p_pid, p->p_comm,
			 fd, fp->f_fglob->fg_type));
		error = EINVAL;
		goto done;
	}

	/* we need at least read permission on the file */
	if (! (fp->f_fglob->fg_flag & FREAD)) {
		SHARED_REGION_TRACE_ERROR(
			("shared_region: %p [%d(%s)] map: "
			 "fd=%d not readable\n",
			 current_thread(), p->p_pid, p->p_comm, fd));
		error = EPERM;
		goto done;
	}

	/* get vnode from file structure */
	error = vnode_getwithref((vnode_t) fp->f_fglob->fg_data);
	if (error) {
		SHARED_REGION_TRACE_ERROR(
			("shared_region: %p [%d(%s)] map: "
			 "fd=%d getwithref failed (error=%d)\n",
			 current_thread(), p->p_pid, p->p_comm, fd, error));
		goto done;
	}
	vp = (struct vnode *) fp->f_fglob->fg_data;

	/* make sure the vnode is a regular file */
	if (vp->v_type != VREG) {
		SHARED_REGION_TRACE_ERROR(
			("shared_region: %p [%d(%s)] map(%p:'%s'): "
			 "not a file (type=%d)\n",
			 current_thread(), p->p_pid, p->p_comm,
			 vp, vp->v_name, vp->v_type));
		error = EINVAL;
		goto done;
	}

	/* make sure vnode is on the process's root volume */
	root_vp = p->p_fd->fd_rdir;
	if (root_vp == NULL) {
		root_vp = rootvnode;
	}
	if (vp->v_mount != root_vp->v_mount) {
		SHARED_REGION_TRACE_ERROR(
			("shared_region: %p [%d(%s)] map(%p:'%s'): "
			 "not on process's root volume\n",
			 current_thread(), p->p_pid, p->p_comm,
			 vp, vp->v_name));
		error = EPERM;
		goto done;
	}

	/* make sure vnode is owned by "root" */
	VATTR_INIT(&va);
	VATTR_WANTED(&va, va_uid);
	error = vnode_getattr(vp, &va, vfs_context_current());
	if (error) {
		SHARED_REGION_TRACE_ERROR(
			("shared_region: %p [%d(%s)] map(%p:'%s'): "
			 "vnode_getattr(%p) failed (error=%d)\n",
			 current_thread(), p->p_pid, p->p_comm,
			 vp, vp->v_name, vp, error));
		goto done;
	}
	if (va.va_uid != 0) {
		SHARED_REGION_TRACE_ERROR(
			("shared_region: %p [%d(%s)] map(%p:'%s'): "
			 "owned by uid=%d instead of 0\n",
			 current_thread(), p->p_pid, p->p_comm,
			 vp, vp->v_name, va.va_uid));
		error = EPERM;
		goto done;
	}

	/* get vnode size */
	error = vnode_size(vp, &fs, vfs_context_current());
	if (error) {
		SHARED_REGION_TRACE_ERROR(
			("shared_region: %p [%d(%s)] map(%p:'%s'): "
			 "vnode_size(%p) failed (error=%d)\n",
			 current_thread(), p->p_pid, p->p_comm,
			 vp, vp->v_name, vp, error));
		goto done;
	}
	file_size = fs;

	/* get the file's memory object handle */
	file_control = ubc_getobject(vp, UBC_HOLDOBJECT);
	if (file_control == MEMORY_OBJECT_CONTROL_NULL) {
		SHARED_REGION_TRACE_ERROR(
			("shared_region: %p [%d(%s)] map(%p:'%s'): "
			 "no memory object\n",
			 current_thread(), p->p_pid, p->p_comm,
			 vp, vp->v_name));
		error = EINVAL;
		goto done;
	}
			 
	/* get the list of mappings the caller wants us to establish */
	mappings_count = uap->count;	/* number of mappings */
	mappings_size = (vm_size_t) (mappings_count * sizeof (mappings[0]));
	if (mappings_count == 0) {
		SHARED_REGION_TRACE_INFO(
			("shared_region: %p [%d(%s)] map(%p:'%s'): "
			 "no mappings\n",
			 current_thread(), p->p_pid, p->p_comm,
			 vp, vp->v_name));
		error = 0;	/* no mappings: we're done ! */
		goto done;
	} else if (mappings_count <= SFM_MAX_STACK) {
		mappings = &stack_mappings[0];
	} else {
		SHARED_REGION_TRACE_ERROR(
			("shared_region: %p [%d(%s)] map(%p:'%s'): "
			 "too many mappings (%d)\n",
			 current_thread(), p->p_pid, p->p_comm,
			 vp, vp->v_name, mappings_count));
		error = EINVAL;
		goto done;
	}

	user_mappings = uap->mappings;	/* the mappings, in user space */
	error = copyin(user_mappings,
		       mappings,
		       mappings_size);
	if (error) {
		SHARED_REGION_TRACE_ERROR(
			("shared_region: %p [%d(%s)] map(%p:'%s'): "
			 "copyin(0x%llx, %d) failed (error=%d)\n",
			 current_thread(), p->p_pid, p->p_comm,
			 vp, vp->v_name, (uint64_t)user_mappings, mappings_count, error));
		goto done;
	}

	/* get the process's shared region (setup in vm_map_exec()) */
	shared_region = vm_shared_region_get(current_task());
	if (shared_region == NULL) {
		SHARED_REGION_TRACE_ERROR(
			("shared_region: %p [%d(%s)] map(%p:'%s'): "
			 "no shared region\n",
			 current_thread(), p->p_pid, p->p_comm,
			 vp, vp->v_name));
		goto done;
	}

	/* map the file into that shared region's submap */
	kr = vm_shared_region_map_file(shared_region,
				       mappings_count,
				       mappings,
				       file_control,
				       file_size,
				       (void *) p->p_fd->fd_rdir);
	if (kr != KERN_SUCCESS) {
		SHARED_REGION_TRACE_ERROR(
			("shared_region: %p [%d(%s)] map(%p:'%s'): "
			 "vm_shared_region_map_file() failed kr=0x%x\n",
			 current_thread(), p->p_pid, p->p_comm,
			 vp, vp->v_name, kr));
		switch (kr) {
		case KERN_INVALID_ADDRESS:
			error = EFAULT;
			break;
		case KERN_PROTECTION_FAILURE:
			error = EPERM;
			break;
		case KERN_NO_SPACE:
			error = ENOMEM;
			break;
		case KERN_FAILURE:
		case KERN_INVALID_ARGUMENT:
		default:
			error = EINVAL;
			break;
		}
		goto done;
	}

	/*
	 * The mapping was successful.  Let the buffer cache know
	 * that we've mapped that file with these protections.  This
	 * prevents the vnode from getting recycled while it's mapped.
	 */
	(void) ubc_map(vp, VM_PROT_READ);
	error = 0;

	/* update the vnode's access time */
	if (! (vnode_vfsvisflags(vp) & MNT_NOATIME)) {
		VATTR_INIT(&va);
		nanotime(&va.va_access_time);
		VATTR_SET_ACTIVE(&va, va_access_time);
		vnode_setattr(vp, &va, vfs_context_current());
	}

	if (p->p_flag & P_NOSHLIB) {
		/* signal that this process is now using split libraries */
		OSBitAndAtomic(~((uint32_t)P_NOSHLIB), (UInt32 *)&p->p_flag);
	}

done:
	if (vp != NULL) {
		/*
		 * release the vnode...
		 * ubc_map() still holds it for us in the non-error case
		 */
		(void) vnode_put(vp);
		vp = NULL;
	}
	if (fp != NULL) {
		/* release the file descriptor */
		fp_drop(p, fd, fp, 0);
		fp = NULL;
	}

	if (shared_region != NULL) {
		vm_shared_region_deallocate(shared_region);
	}

	SHARED_REGION_TRACE_DEBUG(
		("shared_region: %p [%d(%s)] <- map\n",
		 current_thread(), p->p_pid, p->p_comm));

	return error;
}