Exemple #1
0
/*
 * Truncate the file described by dep to the length specified by length.
 */
int
detrunc(struct denode *dep, u_long length, int flags, struct ucred *cred)
{
	int error;
	int allerror;
	u_long eofentry;
	u_long chaintofree;
	daddr_t bn;
	int boff;
	int isadir = dep->de_Attributes & ATTR_DIRECTORY;
	struct buf *bp;
	struct msdosfsmount *pmp = dep->de_pmp;

#ifdef MSDOSFS_DEBUG
	printf("detrunc(): file %s, length %lu, flags %x\n", dep->de_Name, length, flags);
#endif

	/*
	 * Disallow attempts to truncate the root directory since it is of
	 * fixed size.  That's just the way dos filesystems are.  We use
	 * the VROOT bit in the vnode because checking for the directory
	 * bit and a startcluster of 0 in the denode is not adequate to
	 * recognize the root directory at this point in a file or
	 * directory's life.
	 */
	if ((DETOV(dep)->v_vflag & VV_ROOT) && !FAT32(pmp)) {
#ifdef MSDOSFS_DEBUG
		printf("detrunc(): can't truncate root directory, clust %ld, offset %ld\n",
		    dep->de_dirclust, dep->de_diroffset);
#endif
		return (EINVAL);
	}

	if (dep->de_FileSize < length) {
		vnode_pager_setsize(DETOV(dep), length);
		return deextend(dep, length, cred);
	}

	/*
	 * If the desired length is 0 then remember the starting cluster of
	 * the file and set the StartCluster field in the directory entry
	 * to 0.  If the desired length is not zero, then get the number of
	 * the last cluster in the shortened file.  Then get the number of
	 * the first cluster in the part of the file that is to be freed.
	 * Then set the next cluster pointer in the last cluster of the
	 * file to CLUST_EOFE.
	 */
	if (length == 0) {
		chaintofree = dep->de_StartCluster;
		dep->de_StartCluster = 0;
		eofentry = ~0;
	} else {
		error = pcbmap(dep, de_clcount(pmp, length) - 1, 0, 
			       &eofentry, 0);
		if (error) {
#ifdef MSDOSFS_DEBUG
			printf("detrunc(): pcbmap fails %d\n", error);
#endif
			return (error);
		}
	}

	fc_purge(dep, de_clcount(pmp, length));

	/*
	 * If the new length is not a multiple of the cluster size then we
	 * must zero the tail end of the new last cluster in case it
	 * becomes part of the file again because of a seek.
	 */
	if ((boff = length & pmp->pm_crbomask) != 0) {
		if (isadir) {
			bn = cntobn(pmp, eofentry);
			error = bread(pmp->pm_devvp, bn, pmp->pm_bpcluster,
			    NOCRED, &bp);
			if (error) {
				brelse(bp);
#ifdef MSDOSFS_DEBUG
				printf("detrunc(): bread fails %d\n", error);
#endif
				return (error);
			}
			bzero(bp->b_data + boff, pmp->pm_bpcluster - boff);
			if (flags & IO_SYNC)
				bwrite(bp);
			else
				bdwrite(bp);
		}
	}

	/*
	 * Write out the updated directory entry.  Even if the update fails
	 * we free the trailing clusters.
	 */
	dep->de_FileSize = length;
	if (!isadir)
		dep->de_flag |= DE_UPDATE | DE_MODIFIED;
	allerror = vtruncbuf(DETOV(dep), cred, length, pmp->pm_bpcluster);
#ifdef MSDOSFS_DEBUG
	if (allerror)
		printf("detrunc(): vtruncbuf error %d\n", allerror);
#endif
	error = deupdat(dep, !DOINGASYNC((DETOV(dep))));
	if (error != 0 && allerror == 0)
		allerror = error;
#ifdef MSDOSFS_DEBUG
	printf("detrunc(): allerror %d, eofentry %lu\n",
	       allerror, eofentry);
#endif

	/*
	 * If we need to break the cluster chain for the file then do it
	 * now.
	 */
	if (eofentry != ~0) {
		error = fatentry(FAT_GET_AND_SET, pmp, eofentry,
				 &chaintofree, CLUST_EOFE);
		if (error) {
#ifdef MSDOSFS_DEBUG
			printf("detrunc(): fatentry errors %d\n", error);
#endif
			return (error);
		}
		fc_setcache(dep, FC_LASTFC, de_cluster(pmp, length - 1),
			    eofentry);
	}

	/*
	 * Now free the clusters removed from the file because of the
	 * truncation.
	 */
	if (chaintofree != 0 && !MSDOSFSEOF(pmp, chaintofree))
		freeclusterchain(pmp, chaintofree);

	return (allerror);
}
/*
 * dep  - directory entry to copy into the directory
 * ddep - directory to add to
 * depp - return the address of the denode for the created directory entry
 *	  if depp != 0
 * cnp  - componentname needed for Win95 long filenames
 */
int
createde(struct denode *dep, struct denode *ddep, struct denode **depp, struct componentname *cnp)
{
	int error, rberror;
	u_long dirclust, clusoffset;
	u_long fndoffset, havecnt = 0, wcnt = 1, i;
	struct direntry *ndep;
	struct msdosfsmount *pmp = ddep->de_pmp;
	struct buf *bp;
	daddr_t bn;
	int blsize;
#ifdef _KERNEL
	int async = ddep->de_pmp->pm_mountp->mnt_flag & MNT_ASYNC;
#else
#define async 0
#endif

#ifdef MSDOSFS_DEBUG
	printf("createde(dep %p, ddep %p, depp %p, cnp %p)\n",
	    dep, ddep, depp, cnp);
#endif

	/*
	 * If no space left in the directory then allocate another cluster
	 * and chain it onto the end of the file.  There is one exception
	 * to this.  That is, if the root directory has no more space it
	 * can NOT be expanded.  extendfile() checks for and fails attempts
	 * to extend the root directory.  We just return an error in that
	 * case.
	 */
	if (ddep->de_fndoffset >= ddep->de_FileSize) {
		u_long needlen = ddep->de_fndoffset + sizeof(struct direntry)
		    - ddep->de_FileSize;
		dirclust = de_clcount(pmp, needlen);
		if ((error = extendfile(ddep, dirclust, 0, 0, DE_CLEAR)) != 0) {
			(void)detrunc(ddep, ddep->de_FileSize, 0, NOCRED);
			goto err_norollback;
		}

		/*
		 * Update the size of the directory
		 */
		ddep->de_FileSize += de_cn2off(pmp, dirclust);
	}

	/*
	 * We just read in the cluster with space.  Copy the new directory
	 * entry in.  Then write it to disk. NOTE:  DOS directories
	 * do not get smaller as clusters are emptied.
	 */
	error = pcbmap(ddep, de_cluster(pmp, ddep->de_fndoffset),
		       &bn, &dirclust, &blsize);
	if (error)
		goto err_norollback;
	clusoffset = ddep->de_fndoffset;
	if (dirclust != MSDOSFSROOT)
		clusoffset &= pmp->pm_crbomask;
	if ((error = bread(pmp->pm_devvp, de_bn2kb(pmp, bn), blsize, NOCRED,
	    B_MODIFY, &bp)) != 0) {
		goto err_norollback;
	}
	ndep = bptoep(pmp, bp, clusoffset);

	DE_EXTERNALIZE(ndep, dep);

	/*
	 * Now write the Win95 long name
	 */
	if (ddep->de_fndcnt > 0) {
		u_int8_t chksum = winChksum(ndep->deName);
		const u_char *un = (const u_char *)cnp->cn_nameptr;
		int unlen = cnp->cn_namelen;
		u_long xhavecnt;

		fndoffset = ddep->de_fndoffset;
		xhavecnt = ddep->de_fndcnt + 1;

		for(; wcnt < xhavecnt; wcnt++) {
			if ((fndoffset & pmp->pm_crbomask) == 0) {
				/* we should never get here if ddep is root
				 * directory */

				if (async)
					(void) bdwrite(bp);
				else if ((error = bwrite(bp)) != 0)
					goto rollback;

				fndoffset -= sizeof(struct direntry);
				error = pcbmap(ddep,
					       de_cluster(pmp, fndoffset),
					       &bn, 0, &blsize);
				if (error)
					goto rollback;

				error = bread(pmp->pm_devvp, de_bn2kb(pmp, bn),
				    blsize, NOCRED, B_MODIFY, &bp);
				if (error) {
					goto rollback;
				}
				ndep = bptoep(pmp, bp,
						fndoffset & pmp->pm_crbomask);
			} else {
				ndep--;
				fndoffset -= sizeof(struct direntry);
			}
			if (!unix2winfn(un, unlen, (struct winentry *)ndep,
						wcnt, chksum))
				break;
		}
	}

	if (async)
		bdwrite(bp);
	else if ((error = bwrite(bp)) != 0)
		goto rollback;

	/*
	 * If they want us to return with the denode gotten.
	 */
	if (depp) {
		u_long diroffset = clusoffset;
		if (dep->de_Attributes & ATTR_DIRECTORY) {
			dirclust = dep->de_StartCluster;
			if (FAT32(pmp) && dirclust == pmp->pm_rootdirblk)
				dirclust = MSDOSFSROOT;
			if (dirclust == MSDOSFSROOT)
				diroffset = MSDOSFSROOT_OFS;
			else
				diroffset = 0;
		}
		error = deget(pmp, dirclust, diroffset, depp);
#ifndef MAKEFS
		if (error == 0)
			VOP_UNLOCK(DETOV(*depp));
#endif
		return error;
	}

	return 0;

    rollback:
	/*
	 * Mark all slots modified so far as deleted. Note that we
	 * can't just call removede(), since directory is not in
	 * consistent state.
	 */
	fndoffset = ddep->de_fndoffset;
	rberror = pcbmap(ddep, de_cluster(pmp, fndoffset),
	       &bn, NULL, &blsize);
	if (rberror)
		goto err_norollback;
	if ((rberror = bread(pmp->pm_devvp, de_bn2kb(pmp, bn), blsize, NOCRED,
	    B_MODIFY, &bp)) != 0) {
		goto err_norollback;
	}
	ndep = bptoep(pmp, bp, clusoffset);

	havecnt = ddep->de_fndcnt + 1;
	for(i = wcnt; i <= havecnt; i++) {
		/* mark entry as deleted */
		ndep->deName[0] = SLOT_DELETED;

		if ((fndoffset & pmp->pm_crbomask) == 0) {
			/* we should never get here if ddep is root
			 * directory */

			if (async)
				bdwrite(bp);
			else if ((rberror = bwrite(bp)) != 0)
				goto err_norollback;

			fndoffset -= sizeof(struct direntry);
			rberror = pcbmap(ddep,
				       de_cluster(pmp, fndoffset),
				       &bn, 0, &blsize);
			if (rberror)
				goto err_norollback;

			rberror = bread(pmp->pm_devvp, de_bn2kb(pmp, bn),
			    blsize, NOCRED, B_MODIFY, &bp);
			if (rberror) {
				goto err_norollback;
			}
			ndep = bptoep(pmp, bp, fndoffset);
		} else {
			ndep--;
			fndoffset -= sizeof(struct direntry);
		}
	}

	/* ignore any further error */
	if (async)
		(void) bdwrite(bp);
	else
		(void) bwrite(bp);

    err_norollback:
	return error;
}
/*
 * Remove a directory entry. At this point the file represented by the
 * directory entry to be removed is still full length until noone has it
 * open.  When the file no longer being used msdosfs_inactive() is called
 * and will truncate the file to 0 length.  When the vnode containing the
 * denode is needed for some other purpose by VFS it will call
 * msdosfs_reclaim() which will remove the denode from the denode cache.
 */
int
removede(struct denode *pdep, struct denode *dep)
	/* pdep:	 directory where the entry is removed */
	/* dep:	 file to be removed */
{
	int error;
	struct direntry *ep;
	struct buf *bp;
	daddr_t bn;
	int blsize;
	struct msdosfsmount *pmp = pdep->de_pmp;
	u_long offset = pdep->de_fndoffset;
#ifdef _KERNEL
	int async = pdep->de_pmp->pm_mountp->mnt_flag & MNT_ASYNC;
#else
#define async 0
#endif

#ifdef MSDOSFS_DEBUG
	printf("removede(): filename %s, dep %p, offset %08lx\n",
	    dep->de_Name, dep, offset);
#endif

	dep->de_refcnt--;
	offset += sizeof(struct direntry);
	do {
		offset -= sizeof(struct direntry);
		error = pcbmap(pdep, de_cluster(pmp, offset), &bn, 0, &blsize);
		if (error)
			return error;
		error = bread(pmp->pm_devvp, de_bn2kb(pmp, bn), blsize, NOCRED,
		    B_MODIFY, &bp);
		if (error) {
			return error;
		}
		ep = bptoep(pmp, bp, offset);
		/*
		 * Check whether, if we came here the second time, i.e.
		 * when underflowing into the previous block, the last
		 * entry in this block is a longfilename entry, too.
		 */
		if (ep->deAttributes != ATTR_WIN95
		    && offset != pdep->de_fndoffset) {
			brelse(bp, 0);
			break;
		}
		offset += sizeof(struct direntry);
		while (1) {
			/*
			 * We are a bit agressive here in that we delete any Win95
			 * entries preceding this entry, not just the ones we "own".
			 * Since these presumably aren't valid anyway,
			 * there should be no harm.
			 */
			offset -= sizeof(struct direntry);
			ep--->deName[0] = SLOT_DELETED;
			if ((pmp->pm_flags & MSDOSFSMNT_NOWIN95)
			    || !(offset & pmp->pm_crbomask)
			    || ep->deAttributes != ATTR_WIN95)
				break;
		}
		if (async)
			bdwrite(bp);
		else if ((error = bwrite(bp)) != 0)
			return error;
	} while (!(pmp->pm_flags & MSDOSFSMNT_NOWIN95)
	    && !(offset & pmp->pm_crbomask)
	    && offset);
	return 0;
}
Exemple #4
0
/*
 * dep  - directory entry to copy into the directory
 * ddep - directory to add to
 * depp - return the address of the denode for the created directory entry
 *	  if depp != 0
 * cnp  - componentname needed for Win95 long filenames
 */
int
createde(struct denode *dep, struct denode *ddep, struct denode **depp,
	 struct componentname *cnp)
{
	int error;
	u_long dirclust, diroffset;
	struct direntry *ndep;
	struct msdosfsmount *pmp = ddep->de_pmp;
	struct buf *bp;
	daddr_t bn;
	int blsize;

#ifdef MSDOSFS_DEBUG
	kprintf("createde(dep %p, ddep %p, depp %p, cnp %p)\n",
	    dep, ddep, depp, cnp);
#endif

	/*
	 * If no space left in the directory then allocate another cluster
	 * and chain it onto the end of the file.  There is one exception
	 * to this.  That is, if the root directory has no more space it
	 * can NOT be expanded.  extendfile() checks for and fails attempts
	 * to extend the root directory.  We just return an error in that
	 * case.
	 */
	if (ddep->de_fndoffset >= ddep->de_FileSize) {
		diroffset = ddep->de_fndoffset + sizeof(struct direntry)
		    - ddep->de_FileSize;
		dirclust = de_clcount(pmp, diroffset);
		error = extendfile(ddep, dirclust, 0, 0, DE_CLEAR);
		if (error) {
			detrunc(ddep, ddep->de_FileSize, 0);
			return error;
		}

		/*
		 * Update the size of the directory
		 */
		ddep->de_FileSize += de_cn2off(pmp, dirclust);
	}

	/*
	 * We just read in the cluster with space.  Copy the new directory
	 * entry in.  Then write it to disk. NOTE:  DOS directories
	 * do not get smaller as clusters are emptied.
	 */
	error = pcbmap(ddep, de_cluster(pmp, ddep->de_fndoffset),
		       &bn, &dirclust, &blsize);
	if (error)
		return error;
	diroffset = ddep->de_fndoffset;
	if (dirclust != MSDOSFSROOT)
		diroffset &= pmp->pm_crbomask;
	if ((error = bread(pmp->pm_devvp, de_bntodoff(pmp, bn), blsize, &bp)) != 0) {
		brelse(bp);
		return error;
	}
	ndep = bptoep(pmp, bp, ddep->de_fndoffset);

	DE_EXTERNALIZE(ndep, dep);

	/*
	 * Now write the Win95 long name
	 */
	if (ddep->de_fndcnt > 0) {
		u_int8_t chksum = winChksum(ndep->deName);
		const u_char *un = (const u_char *)cnp->cn_nameptr;
		int unlen = cnp->cn_namelen;
		int cnt = 1;

		while (--ddep->de_fndcnt >= 0) {
			if (!(ddep->de_fndoffset & pmp->pm_crbomask)) {
				if ((error = bwrite(bp)) != 0)
					return error;

				ddep->de_fndoffset -= sizeof(struct direntry);
				error = pcbmap(ddep,
					       de_cluster(pmp,
							  ddep->de_fndoffset),
					       &bn, NULL, &blsize);
				if (error)
					return error;

				error = bread(pmp->pm_devvp, de_bntodoff(pmp, bn), blsize, &bp);
				if (error) {
					brelse(bp);
					return error;
				}
				ndep = bptoep(pmp, bp, ddep->de_fndoffset);
			} else {
				ndep--;
				ddep->de_fndoffset -= sizeof(struct direntry);
			}
			if (!unix2winfn(un, unlen, (struct winentry *)ndep,
					cnt++, chksum,
					pmp))
				break;
		}
	}

	if ((error = bwrite(bp)) != 0)
		return error;

	/*
	 * If they want us to return with the denode gotten.
	 */
	if (depp) {
		if (dep->de_Attributes & ATTR_DIRECTORY) {
			dirclust = dep->de_StartCluster;
			if (FAT32(pmp) && dirclust == pmp->pm_rootdirblk)
				dirclust = MSDOSFSROOT;
			if (dirclust == MSDOSFSROOT)
				diroffset = MSDOSFSROOT_OFS;
			else
				diroffset = 0;
		}
		return deget(pmp, dirclust, diroffset, depp);
	}

	return 0;
}
Exemple #5
0
/*
 * Renames on files require moving the denode to a new hash queue since the
 * denode's location is used to compute which hash queue to put the file
 * in. Unless it is a rename in place.  For example "mv a b".
 *
 * What follows is the basic algorithm:
 *
 * if (file move) {
 *	if (dest file exists) {
 *		remove dest file
 *	}
 *	if (dest and src in same directory) {
 *		rewrite name in existing directory slot
 *	} else {
 *		write new entry in dest directory
 *		update offset and dirclust in denode
 *		move denode to new hash chain
 *		clear old directory entry
 *	}
 * } else {
 *	directory move
 *	if (dest directory exists) {
 *		if (dest is not empty) {
 *			return ENOTEMPTY
 *		}
 *		remove dest directory
 *	}
 *	if (dest and src in same directory) {
 *		rewrite name in existing entry
 *	} else {
 *		be sure dest is not a child of src directory
 *		write entry in dest directory
 *		update "." and ".." in moved directory
 *		update offset and dirclust in denode
 *		move denode to new hash chain
 *		clear old directory entry for moved directory
 *	}
 * }
 *
 * On entry:
 *	source's parent directory is unlocked
 *	source file or directory is unlocked
 *	destination's parent directory is locked
 *	destination file or directory is locked if it exists
 *
 * On exit:
 *	all denodes should be released
 *
 * Notes:
 * I'm not sure how the memory containing the pathnames pointed at by the
 * componentname structures is freed, there may be some memory bleeding
 * for each rename done.
 */
int
msdosfs_rename(void *v)
{
	struct vop_rename_args *ap = v;
	struct vnode *tvp = ap->a_tvp;
	struct vnode *tdvp = ap->a_tdvp;
	struct vnode *fvp = ap->a_fvp;
	struct vnode *fdvp = ap->a_fdvp;
	struct componentname *tcnp = ap->a_tcnp;
	struct componentname *fcnp = ap->a_fcnp;
	struct proc *p = curproc; /* XXX */
	struct denode *ip, *xp, *dp, *zp;
	u_char toname[11], oldname[11];
	uint32_t from_diroffset, to_diroffset;
	u_char to_count;
	int doingdirectory = 0, newparent = 0;
	int error;
	uint32_t cn, pcl;
	daddr64_t bn;
	struct msdosfsmount *pmp;
	struct direntry *dotdotp;
	struct buf *bp;

	pmp = VFSTOMSDOSFS(fdvp->v_mount);

#ifdef DIAGNOSTIC
	if ((tcnp->cn_flags & HASBUF) == 0 ||
	    (fcnp->cn_flags & HASBUF) == 0)
		panic("msdosfs_rename: no name");
#endif
	/*
	 * Check for cross-device rename.
	 */
	if ((fvp->v_mount != tdvp->v_mount) ||
	    (tvp && (fvp->v_mount != tvp->v_mount))) {
		error = EXDEV;
abortit:
		VOP_ABORTOP(tdvp, tcnp);
		if (tdvp == tvp)
			vrele(tdvp);
		else
			vput(tdvp);
		if (tvp)
			vput(tvp);
		VOP_ABORTOP(fdvp, fcnp);
		vrele(fdvp);
		vrele(fvp);
		return (error);
	}
	
	/*
	 * If source and dest are the same, do nothing.
	 */
	if (tvp == fvp) {
		error = 0;
		goto abortit;
	}

	/* */
	if ((error = vn_lock(fvp, LK_EXCLUSIVE | LK_RETRY, p)) != 0)
		goto abortit;
	dp = VTODE(fdvp);
	ip = VTODE(fvp);

	/*
	 * Be sure we are not renaming ".", "..", or an alias of ".". This
	 * leads to a crippled directory tree.  It's pretty tough to do a
	 * "ls" or "pwd" with the "." directory entry missing, and "cd .."
	 * doesn't work if the ".." entry is missing.
	 */
	if (ip->de_Attributes & ATTR_DIRECTORY) {
		/*
		 * Avoid ".", "..", and aliases of "." for obvious reasons.
		 */
		if ((fcnp->cn_namelen == 1 && fcnp->cn_nameptr[0] == '.') ||
		    dp == ip ||
		    (fcnp->cn_flags & ISDOTDOT) ||
		    (tcnp->cn_flags & ISDOTDOT) ||
		    (ip->de_flag & DE_RENAME)) {
			VOP_UNLOCK(fvp, 0, p);
			error = EINVAL;
			goto abortit;
		}
		ip->de_flag |= DE_RENAME;
		doingdirectory++;
	}

	/*
	 * When the target exists, both the directory
	 * and target vnodes are returned locked.
	 */
	dp = VTODE(tdvp);
	xp = tvp ? VTODE(tvp) : NULL;
	/*
	 * Remember direntry place to use for destination
	 */
	to_diroffset = dp->de_fndoffset;
	to_count = dp->de_fndcnt;

	/*
	 * If ".." must be changed (ie the directory gets a new
	 * parent) then the source directory must not be in the
	 * directory hierarchy above the target, as this would
	 * orphan everything below the source directory. Also
	 * the user must have write permission in the source so
	 * as to be able to change "..". We must repeat the call
	 * to namei, as the parent directory is unlocked by the
	 * call to doscheckpath().
	 */
	error = VOP_ACCESS(fvp, VWRITE, tcnp->cn_cred, tcnp->cn_proc);
	VOP_UNLOCK(fvp, 0, p);
	if (VTODE(fdvp)->de_StartCluster != VTODE(tdvp)->de_StartCluster)
		newparent = 1;
	vrele(fdvp);
	if (doingdirectory && newparent) {
		if (error)	/* write access check above */
			goto bad1;
		if (xp != NULL)
			vput(tvp);
		/*
		 * doscheckpath() vput()'s dp,
		 * so we have to do a relookup afterwards
		 */
		if ((error = doscheckpath(ip, dp)) != 0)
			goto out;
		if ((tcnp->cn_flags & SAVESTART) == 0)
			panic("msdosfs_rename: lost to startdir");
		if ((error = vfs_relookup(tdvp, &tvp, tcnp)) != 0)
			goto out;
		dp = VTODE(tdvp);
		xp = tvp ? VTODE(tvp) : NULL;
	}

	if (xp != NULL) {
		/*
		 * Target must be empty if a directory and have no links
		 * to it. Also, ensure source and target are compatible
		 * (both directories, or both not directories).
		 */
		if (xp->de_Attributes & ATTR_DIRECTORY) {
			if (!dosdirempty(xp)) {
				error = ENOTEMPTY;
				goto bad1;
			}
			if (!doingdirectory) {
				error = ENOTDIR;
				goto bad1;
			}
			cache_purge(tdvp);
		} else if (doingdirectory) {
			error = EISDIR;
			goto bad1;
		}
		if ((error = removede(dp, xp)) != 0)
			goto bad1;
		vput(tvp);
		xp = NULL;
	}

	/*
	 * Convert the filename in tcnp into a dos filename. We copy this
	 * into the denode and directory entry for the destination
	 * file/directory.
	 */
	if ((error = uniqdosname(VTODE(tdvp), tcnp, toname)) != 0)
		goto bad1;

	/*
	 * Since from wasn't locked at various places above,
	 * have to do a relookup here.
	 */
	fcnp->cn_flags &= ~MODMASK;
	fcnp->cn_flags |= LOCKPARENT | LOCKLEAF;
	if ((fcnp->cn_flags & SAVESTART) == 0)
		panic("msdosfs_rename: lost from startdir");
	if (!newparent)
		VOP_UNLOCK(tdvp, 0, p);
	(void) vfs_relookup(fdvp, &fvp, fcnp);
	if (fvp == NULL) {
		/*
		 * From name has disappeared.
		 */
		if (doingdirectory)
			panic("rename: lost dir entry");
		vrele(ap->a_fvp);
		if (newparent)
			VOP_UNLOCK(tdvp, 0, p);
		vrele(tdvp);
		return 0;
	}
	xp = VTODE(fvp);
	zp = VTODE(fdvp);
	from_diroffset = zp->de_fndoffset;

	/*
	 * Ensure that the directory entry still exists and has not
	 * changed till now. If the source is a file the entry may
	 * have been unlinked or renamed. In either case there is
	 * no further work to be done. If the source is a directory
	 * then it cannot have been rmdir'ed or renamed; this is
	 * prohibited by the DE_RENAME flag.
	 */
	if (xp != ip) {
		if (doingdirectory)
			panic("rename: lost dir entry");
		vrele(ap->a_fvp);
		if (newparent)
			VOP_UNLOCK(fdvp, 0, p);
		xp = NULL;
	} else {
		vrele(fvp);
		xp = NULL;

		/*
		 * First write a new entry in the destination
		 * directory and mark the entry in the source directory
		 * as deleted.  Then move the denode to the correct hash
		 * chain for its new location in the filesystem.  And, if
		 * we moved a directory, then update its .. entry to point
		 * to the new parent directory.
		 */
		bcopy(ip->de_Name, oldname, 11);
		bcopy(toname, ip->de_Name, 11);	/* update denode */
		dp->de_fndoffset = to_diroffset;
		dp->de_fndcnt = to_count;
		error = createde(ip, dp, (struct denode **)0, tcnp);
		if (error) {
			bcopy(oldname, ip->de_Name, 11);
			if (newparent)
				VOP_UNLOCK(fdvp, 0, p);
			goto bad;
		}
		ip->de_refcnt++;
		zp->de_fndoffset = from_diroffset;
		if ((error = removede(zp, ip)) != 0) {
			/* XXX should really panic here, fs is corrupt */
			if (newparent)
				VOP_UNLOCK(fdvp, 0, p);
			goto bad;
		}

		cache_purge(fvp);

		if (!doingdirectory) {
			error = pcbmap(dp, de_cluster(pmp, to_diroffset), 0,
				       &ip->de_dirclust, 0);
			if (error) {
				/* XXX should really panic here, fs is corrupt */
				if (newparent)
					VOP_UNLOCK(fdvp, 0, p);
				goto bad;
			}
			if (ip->de_dirclust != MSDOSFSROOT)
				ip->de_diroffset = to_diroffset & pmp->pm_crbomask;
		}
		reinsert(ip);
		if (newparent)
			VOP_UNLOCK(fdvp, 0, p);
	}

	/*
	 * If we moved a directory to a new parent directory, then we must
	 * fixup the ".." entry in the moved directory.
	 */
	if (doingdirectory && newparent) {
		cn = ip->de_StartCluster;
		if (cn == MSDOSFSROOT) {
			/* this should never happen */
			panic("msdosfs_rename: updating .. in root directory?");
		} else
			bn = cntobn(pmp, cn);
		error = bread(pmp->pm_devvp, bn, pmp->pm_bpcluster,
			      NOCRED, &bp);
		if (error) {
			/* XXX should really panic here, fs is corrupt */
			brelse(bp);
			goto bad;
		}
		dotdotp = (struct direntry *)bp->b_data;
		putushort(dotdotp[0].deStartCluster, cn);
		pcl = dp->de_StartCluster;
		if (FAT32(pmp) && pcl == pmp->pm_rootdirblk)
			pcl = 0;
		putushort(dotdotp[1].deStartCluster, pcl);
		if (FAT32(pmp)) {
			putushort(dotdotp[0].deHighClust, cn >> 16);
			putushort(dotdotp[1].deHighClust, pcl >> 16);
		}
		if ((error = bwrite(bp)) != 0) {
			/* XXX should really panic here, fs is corrupt */
			goto bad;
		}
	}
Exemple #6
0
/*
 * Write data to a file or directory.
 */
int
msdosfs_write(void *v)
{
	struct vop_write_args *ap = v;
	int n;
	int croffset;
	int resid;
	uint32_t osize;
	int error = 0;
	uint32_t count, lastcn;
	daddr64_t bn;
	struct buf *bp;
	int ioflag = ap->a_ioflag;
	struct uio *uio = ap->a_uio;
	struct proc *p = uio->uio_procp;
	struct vnode *vp = ap->a_vp;
	struct vnode *thisvp;
	struct denode *dep = VTODE(vp);
	struct msdosfsmount *pmp = dep->de_pmp;
	struct ucred *cred = ap->a_cred;

#ifdef MSDOSFS_DEBUG
	printf("msdosfs_write(vp %08x, uio %08x, ioflag %08x, cred %08x\n",
	    vp, uio, ioflag, cred);
	printf("msdosfs_write(): diroff %d, dirclust %d, startcluster %d\n",
	    dep->de_diroffset, dep->de_dirclust, dep->de_StartCluster);
#endif

	switch (vp->v_type) {
	case VREG:
		if (ioflag & IO_APPEND)
			uio->uio_offset = dep->de_FileSize;
		thisvp = vp;
		break;
	case VDIR:
		return EISDIR;
	default:
		panic("msdosfs_write(): bad file type");
	}

	if (uio->uio_offset < 0)
		return (EINVAL);

	if (uio->uio_resid == 0)
		return (0);

	/* Don't bother to try to write files larger than the f/s limit */
	if (uio->uio_offset + uio->uio_resid > MSDOSFS_FILESIZE_MAX)
		return (EFBIG);

	/*
	 * If they've exceeded their filesize limit, tell them about it.
	 */
	if (p &&
	    ((uio->uio_offset + uio->uio_resid) >
	    p->p_rlimit[RLIMIT_FSIZE].rlim_cur)) {
		psignal(p, SIGXFSZ);
		return (EFBIG);
	}

	/*
	 * If the offset we are starting the write at is beyond the end of
	 * the file, then they've done a seek.  Unix filesystems allow
	 * files with holes in them, DOS doesn't so we must fill the hole
	 * with zeroed blocks.
	 */
	if (uio->uio_offset > dep->de_FileSize) {
		if ((error = deextend(dep, uio->uio_offset, cred)) != 0)
			return (error);
	}

	/*
	 * Remember some values in case the write fails.
	 */
	resid = uio->uio_resid;
	osize = dep->de_FileSize;

	/*
	 * If we write beyond the end of the file, extend it to its ultimate
	 * size ahead of the time to hopefully get a contiguous area.
	 */
	if (uio->uio_offset + resid > osize) {
		count = de_clcount(pmp, uio->uio_offset + resid) -
			de_clcount(pmp, osize);
		if ((error = extendfile(dep, count, NULL, NULL, 0)) &&
		    (error != ENOSPC || (ioflag & IO_UNIT)))
			goto errexit;
		lastcn = dep->de_fc[FC_LASTFC].fc_frcn;
	} else
		lastcn = de_clcount(pmp, osize) - 1;

	do {
		if (de_cluster(pmp, uio->uio_offset) > lastcn) {
			error = ENOSPC;
			break;
		}

		bn = de_blk(pmp, uio->uio_offset);
		if ((uio->uio_offset & pmp->pm_crbomask) == 0
		    && (de_blk(pmp, uio->uio_offset + uio->uio_resid) > de_blk(pmp, uio->uio_offset)
			|| uio->uio_offset + uio->uio_resid >= dep->de_FileSize)) {
			/*
			 * If either the whole cluster gets written,
			 * or we write the cluster from its start beyond EOF,
			 * then no need to read data from disk.
			 */
			bp = getblk(thisvp, bn, pmp->pm_bpcluster, 0, 0);
			clrbuf(bp);
			/*
			 * Do the bmap now, since pcbmap needs buffers
			 * for the fat table. (see msdosfs_strategy)
			 */
			if (bp->b_blkno == bp->b_lblkno) {
				error = pcbmap(dep,
					       de_bn2cn(pmp, bp->b_lblkno),
					       &bp->b_blkno, 0, 0);
				if (error)
					bp->b_blkno = -1;
			}
			if (bp->b_blkno == -1) {
				brelse(bp);
				if (!error)
					error = EIO;		/* XXX */
				break;
			}
		} else {
			/*
			 * The block we need to write into exists, so read it in.
			 */
			error = bread(thisvp, bn, pmp->pm_bpcluster,
				      NOCRED, &bp);
			if (error) {
				brelse(bp);
				break;
			}
		}

		croffset = uio->uio_offset & pmp->pm_crbomask;
		n = min(uio->uio_resid, pmp->pm_bpcluster - croffset);
		if (uio->uio_offset + n > dep->de_FileSize) {
			dep->de_FileSize = uio->uio_offset + n;
			uvm_vnp_setsize(vp, dep->de_FileSize);
		}
		uvm_vnp_uncache(vp);
		/*
		 * Should these vnode_pager_* functions be done on dir
		 * files?
		 */

		/*
		 * Copy the data from user space into the buf header.
		 */
		error = uiomove(bp->b_data + croffset, n, uio);

		/*
		 * If they want this synchronous then write it and wait for
		 * it.  Otherwise, if on a cluster boundary write it
		 * asynchronously so we can move on to the next block
		 * without delay.  Otherwise do a delayed write because we
		 * may want to write somemore into the block later.
		 */
		if (ioflag & IO_SYNC)
			(void) bwrite(bp);
		else if (n + croffset == pmp->pm_bpcluster)
			bawrite(bp);
		else
			bdwrite(bp);
		dep->de_flag |= DE_UPDATE;
	} while (error == 0 && uio->uio_resid > 0);

	/*
	 * If the write failed and they want us to, truncate the file back
	 * to the size it was before the write was attempted.
	 */
errexit:
	if (error) {
		if (ioflag & IO_UNIT) {
			detrunc(dep, osize, ioflag & IO_SYNC, NOCRED, NULL);
			uio->uio_offset -= resid - uio->uio_resid;
			uio->uio_resid = resid;
		} else {
			detrunc(dep, dep->de_FileSize, ioflag & IO_SYNC, NOCRED, NULL);
			if (uio->uio_resid != resid)
				error = 0;
		}
	} else if (ioflag & IO_SYNC)
		error = deupdat(dep, 1);
	return (error);
}
Exemple #7
0
int
msdosfs_read(void *v)
{
	struct vop_read_args *ap = v;
	int error = 0;
	uint32_t diff;
	int blsize;
	int isadir;
	uint32_t n;
	long on;
	daddr64_t lbn, rablock, rablkno;
	struct buf *bp;
	struct vnode *vp = ap->a_vp;
	struct denode *dep = VTODE(vp);
	struct msdosfsmount *pmp = dep->de_pmp;
	struct uio *uio = ap->a_uio;

	/*
	 * If they didn't ask for any data, then we are done.
	 */
	if (uio->uio_resid == 0)
		return (0);
	if (uio->uio_offset < 0)
		return (EINVAL);

	isadir = dep->de_Attributes & ATTR_DIRECTORY;
	do {
		if (uio->uio_offset >= dep->de_FileSize)
			return (0);

		lbn = de_cluster(pmp, uio->uio_offset);
		on = uio->uio_offset & pmp->pm_crbomask;
		n = min((uint32_t) (pmp->pm_bpcluster - on), uio->uio_resid);

		/*
		 * de_FileSize is uint32_t, and we know that uio_offset <
		 * de_FileSize, so uio->uio_offset < 2^32.  Therefore
		 * the cast to uint32_t on the next line is safe.
		 */
		diff = dep->de_FileSize - (uint32_t)uio->uio_offset;
		if (diff < n)
			n = diff;

		/* convert cluster # to block # if a directory */
		if (isadir) {
			error = pcbmap(dep, lbn, &lbn, 0, &blsize);
			if (error)
				return (error);
		}
		/*
		 * If we are operating on a directory file then be sure to
		 * do i/o with the vnode for the filesystem instead of the
		 * vnode for the directory.
		 */
		if (isadir) {
			error = bread(pmp->pm_devvp, lbn, blsize, NOCRED, &bp);
		} else {
			rablock = lbn + 1;
			rablkno = de_cn2bn(pmp, rablock);
			if (dep->de_lastr + 1 == lbn &&
			    de_cn2off(pmp, rablock) < dep->de_FileSize)
				error = breadn(vp, de_cn2bn(pmp, lbn),
				    pmp->pm_bpcluster, &rablkno,
				    &pmp->pm_bpcluster, 1, NOCRED, &bp);
			else
				error = bread(vp, de_cn2bn(pmp, lbn),
				    pmp->pm_bpcluster, NOCRED, &bp);
			dep->de_lastr = lbn;
		}
		n = min(n, pmp->pm_bpcluster - bp->b_resid);
		if (error) {
			brelse(bp);
			return (error);
		}
		error = uiomove(bp->b_data + on, (int) n, uio);
		brelse(bp);
	} while (error == 0 && uio->uio_resid > 0 && n != 0);
	if (!isadir && !(vp->v_mount->mnt_flag & MNT_NOATIME))
		dep->de_flag |= DE_ACCESS;
	return (error);
}
Exemple #8
0
int
msdosfs_readdir(void *v)
{
	struct vop_readdir_args *ap = v;
	int error = 0;
	int diff;
	long n;
	int blsize;
	long on;
	long lost;
	long count;
	uint32_t dirsperblk;
	uint32_t cn, lbn;
	uint32_t fileno;
	long bias = 0;
	daddr64_t bn;
	struct buf *bp;
	struct denode *dep = VTODE(ap->a_vp);
	struct msdosfsmount *pmp = dep->de_pmp;
	struct direntry *dentp;
	struct dirent dirbuf;
	struct uio *uio = ap->a_uio;
	u_long *cookies = NULL;
	int ncookies = 0;
	off_t offset, wlast = -1;
	int chksum = -1;

#ifdef MSDOSFS_DEBUG
	printf("msdosfs_readdir(): vp %08x, uio %08x, cred %08x, eofflagp %08x\n",
	    ap->a_vp, uio, ap->a_cred, ap->a_eofflag);
#endif

	/*
	 * msdosfs_readdir() won't operate properly on regular files since
	 * it does i/o only with the filesystem vnode, and hence can
	 * retrieve the wrong block from the buffer cache for a plain file.
	 * So, fail attempts to readdir() on a plain file.
	 */
	if ((dep->de_Attributes & ATTR_DIRECTORY) == 0)
		return (ENOTDIR);

	/*
	 * To be safe, initialize dirbuf
	 */
	bzero(dirbuf.d_name, sizeof(dirbuf.d_name));

	/*
	 * If the user buffer is smaller than the size of one dos directory
	 * entry or the file offset is not a multiple of the size of a
	 * directory entry, then we fail the read.
	 */
	count = uio->uio_resid & ~(sizeof(struct direntry) - 1);
	offset = uio->uio_offset;
	if (count < sizeof(struct direntry) ||
	    (offset & (sizeof(struct direntry) - 1)))
		return (EINVAL);
	lost = uio->uio_resid - count;
	uio->uio_resid = count;

	if (ap->a_ncookies) {
		ncookies = uio->uio_resid / sizeof(struct direntry) + 3;
		cookies = malloc(ncookies * sizeof(u_long), M_TEMP, M_WAITOK);
		*ap->a_cookies = cookies;
		*ap->a_ncookies = ncookies;
	}

	dirsperblk = pmp->pm_BytesPerSec / sizeof(struct direntry);

	/*
	 * If they are reading from the root directory then, we simulate
	 * the . and .. entries since these don't exist in the root
	 * directory.  We also set the offset bias to make up for having to
	 * simulate these entries. By this I mean that at file offset 64 we
	 * read the first entry in the root directory that lives on disk.
	 */
	if (dep->de_StartCluster == MSDOSFSROOT
	    || (FAT32(pmp) && dep->de_StartCluster == pmp->pm_rootdirblk)) {
#if 0
		printf("msdosfs_readdir(): going after . or .. in root dir, offset %d\n",
		    offset);
#endif
		bias = 2 * sizeof(struct direntry);
		if (offset < bias) {
			for (n = (int)offset / sizeof(struct direntry);
			     n < 2; n++) {
			        if (FAT32(pmp))
				        dirbuf.d_fileno = pmp->pm_rootdirblk;
				else
				        dirbuf.d_fileno = 1;
				dirbuf.d_type = DT_DIR;
				switch (n) {
				case 0:
					dirbuf.d_namlen = 1;
					strlcpy(dirbuf.d_name, ".",
					    sizeof dirbuf.d_name);
					break;
				case 1:
					dirbuf.d_namlen = 2;
					strlcpy(dirbuf.d_name, "..",
					    sizeof dirbuf.d_name);
					break;
				}
				dirbuf.d_reclen = DIRENT_SIZE(&dirbuf);
				if (uio->uio_resid < dirbuf.d_reclen)
					goto out;
				error = uiomove((caddr_t) &dirbuf,
						dirbuf.d_reclen, uio);
				if (error)
					goto out;
				offset += sizeof(struct direntry);
				if (cookies) {
					*cookies++ = offset;
					if (--ncookies <= 0)
						goto out;
				}
			}
		}
	}

	while (uio->uio_resid > 0) {
		lbn = de_cluster(pmp, offset - bias);
		on = (offset - bias) & pmp->pm_crbomask;
		n = min(pmp->pm_bpcluster - on, uio->uio_resid);
		diff = dep->de_FileSize - (offset - bias);
		if (diff <= 0)
			break;
		n = min(n, diff);
		if ((error = pcbmap(dep, lbn, &bn, &cn, &blsize)) != 0)
			break;
		error = bread(pmp->pm_devvp, bn, blsize, NOCRED, &bp);
		if (error) {
			brelse(bp);
			return (error);
		}
		n = min(n, blsize - bp->b_resid);

		/*
		 * Convert from dos directory entries to fs-independent
		 * directory entries.
		 */
		for (dentp = (struct direntry *)(bp->b_data + on);
		     (char *)dentp < bp->b_data + on + n;
		     dentp++, offset += sizeof(struct direntry)) {
#if 0
			printf("rd: dentp %08x prev %08x crnt %08x deName %02x attr %02x\n",
			    dentp, prev, crnt, dentp->deName[0], dentp->deAttributes);
#endif
			/*
			 * If this is an unused entry, we can stop.
			 */
			if (dentp->deName[0] == SLOT_EMPTY) {
				brelse(bp);
				goto out;
			}
			/*
			 * Skip deleted entries.
			 */
			if (dentp->deName[0] == SLOT_DELETED) {
				chksum = -1;
				wlast = -1;
				continue;
			}

			/*
			 * Handle Win95 long directory entries
			 */
			if (dentp->deAttributes == ATTR_WIN95) {
				struct winentry *wep;
				if (pmp->pm_flags & MSDOSFSMNT_SHORTNAME)
					continue;
				wep = (struct winentry *)dentp;
				chksum = win2unixfn(wep, &dirbuf, chksum);
				if (wep->weCnt & WIN_LAST)
					wlast = offset;
				continue;
			}

			/*
			 * Skip volume labels
			 */
			if (dentp->deAttributes & ATTR_VOLUME) {
				chksum = -1;
				wlast = -1;
				continue;
			}

			/*
			 * This computation of d_fileno must match
			 * the computation of va_fileid in
			 * msdosfs_getattr.
			 */
			fileno = getushort(dentp->deStartCluster);
			if (FAT32(pmp))
			    fileno |= getushort(dentp->deHighClust) << 16;

			if (dentp->deAttributes & ATTR_DIRECTORY) {
				/* Special-case root */
				if (fileno == MSDOSFSROOT)  {
					fileno = FAT32(pmp) ?
					    pmp->pm_rootdirblk : 1;
				}

				dirbuf.d_fileno = fileno;
				dirbuf.d_type = DT_DIR;
			} else {
				if (getulong(dentp->deFileSize) == 0) {
					uint64_t fileno64;

					fileno64 = (cn == MSDOSFSROOT) ?
					    roottobn(pmp, 0) : cntobn(pmp, cn);

					fileno64 *= dirsperblk;
					fileno64 += dentp -
					    (struct direntry *)bp->b_data;

					fileno = fileidhash(fileno64);
				}

				dirbuf.d_fileno = fileno;
				dirbuf.d_type = DT_REG;
			}

			if (chksum != winChksum(dentp->deName))
				dirbuf.d_namlen = dos2unixfn(dentp->deName,
				    (u_char *)dirbuf.d_name,
				    pmp->pm_flags & MSDOSFSMNT_SHORTNAME);
			else
				dirbuf.d_name[dirbuf.d_namlen] = 0;
			chksum = -1;
			dirbuf.d_reclen = DIRENT_SIZE(&dirbuf);
			if (uio->uio_resid < dirbuf.d_reclen) {
				brelse(bp);
				/* Remember long-name offset. */
				if (wlast != -1)
					offset = wlast;
				goto out;
			}
			wlast = -1;
			error = uiomove((caddr_t) &dirbuf,
					dirbuf.d_reclen, uio);
			if (error) {
				brelse(bp);
				goto out;
			}
			if (cookies) {
				*cookies++ = offset + sizeof(struct direntry);
				if (--ncookies <= 0) {
					brelse(bp);
					goto out;
				}
			}
		}
		brelse(bp);
	}

out:
	/* Subtract unused cookies */
	if (ap->a_ncookies)
		*ap->a_ncookies -= ncookies;

	uio->uio_offset = offset;
	uio->uio_resid += lost;
	if (dep->de_FileSize - (offset - bias) <= 0)
		*ap->a_eofflag = 1;
	else
		*ap->a_eofflag = 0;
	return (error);
}