freebsd-nq/sys/fs/udf/udf_vfsops.c
Scott Long 1703656a17 Factor out some ugle code that's shared by udf_readdir and udf_lookup.
Significantly de-obfuscate udf_lookup

Inspired By: tes@sgi.com
2002-08-15 00:43:43 +00:00

767 lines
18 KiB
C

/*-
* Copyright (c) 2001, 2002 Scott Long <scottl@freebsd.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
/* udf_vfsops.c */
/* Implement the VFS side of things */
/*
* Ok, here's how it goes. The UDF specs are pretty clear on how each data
* structure is made up, but not very clear on how they relate to each other.
* Here is the skinny... This demostrates a filesystem with one file in the
* root directory. Subdirectories are treated just as normal files, but they
* have File Id Descriptors of their children as their file data. As for the
* Anchor Volume Descriptor Pointer, it can exist in two of the following three
* places: sector 256, sector n (the max sector of the disk), or sector
* n - 256. It's a pretty good bet that one will exist at sector 256 though.
* One caveat is unclosed CD media. For that, sector 256 cannot be written,
* so the Anchor Volume Descriptor Pointer can exist at sector 512 until the
* media is closed.
*
* Sector:
* 256:
* n: Anchor Volume Descriptor Pointer
* n - 256: |
* |
* |-->Main Volume Descriptor Sequence
* | |
* | |
* | |-->Logical Volume Descriptor
* | |
* |-->Partition Descriptor |
* | |
* | |
* |-->Fileset Descriptor
* |
* |
* |-->Root Dir File Entry
* |
* |
* |-->File data:
* File Id Descriptor
* |
* |
* |-->File Entry
* |
* |
* |-->File data
*/
#include <sys/types.h>
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/uio.h>
#include <sys/bio.h>
#include <sys/buf.h>
#include <sys/conf.h>
#include <sys/dirent.h>
#include <sys/fcntl.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/mount.h>
#include <sys/namei.h>
#include <sys/proc.h>
#include <sys/queue.h>
#include <sys/vnode.h>
#include <vm/uma.h>
#include <fs/udf/ecma167-udf.h>
#include <fs/udf/udf.h>
#include <fs/udf/osta.h>
MALLOC_DEFINE(M_UDFMOUNT, "UDF mount", "UDF mount structure");
MALLOC_DEFINE(M_UDFFENTRY, "UDF fentry", "UDF file entry structure");
MALLOC_DEFINE(M_UDFSTABLE, "UDF s_table", "UDF sparing table");
/* Zones */
uma_zone_t udf_zone_trans = NULL;
uma_zone_t udf_zone_node = NULL;
uma_zone_t udf_zone_ds = NULL;
static int udf_init(struct vfsconf *);
static int udf_uninit(struct vfsconf *);
static int udf_mount(struct mount *, struct nameidata *, struct thread *);
static int udf_unmount(struct mount *, int, struct thread *);
static int udf_root(struct mount *, struct vnode **);
static int udf_statfs(struct mount *, struct statfs *, struct thread *);
static int udf_fhtovp(struct mount *, struct fid *, struct vnode **);
static int udf_vptofh(struct vnode *, struct fid *);
static int udf_find_partmaps(struct udf_mnt *, struct logvol_desc *);
static struct vfsops udf_vfsops = {
NULL,
vfs_stdstart,
udf_unmount,
udf_root,
vfs_stdquotactl,
udf_statfs,
vfs_stdsync,
udf_vget,
udf_fhtovp,
vfs_stdcheckexp,
udf_vptofh,
udf_init,
udf_uninit,
vfs_stdextattrctl,
udf_mount,
};
VFS_SET(udf_vfsops, udf, VFCF_READONLY);
static int udf_mountfs(struct vnode *, struct mount *, struct thread *);
static int
udf_init(struct vfsconf *foo)
{
/*
* This code used to pre-allocate a certain number of pages for each
* pool, reducing the need to grow the zones later on. UMA doesn't
* advertise any such functionality, unfortunately =-<
*/
udf_zone_trans = uma_zcreate("UDF translation buffer, zone", MAXNAMLEN *
sizeof(unicode_t), NULL, NULL, NULL, NULL, 0, 0);
udf_zone_node = uma_zcreate("UDF Node zone", sizeof(struct udf_node),
NULL, NULL, NULL, NULL, 0, 0);
udf_zone_ds = uma_zcreate("UDF Dirstream zone",
sizeof(struct udf_dirstream), NULL, NULL, NULL, NULL, 0, 0);
if ((udf_zone_node == NULL) || (udf_zone_trans == NULL) ||
(udf_zone_ds == NULL)) {
printf("Cannot create allocation zones.\n");
return (ENOMEM);
}
return 0;
}
static int
udf_uninit(struct vfsconf *foo)
{
if (udf_zone_trans != NULL) {
uma_zdestroy(udf_zone_trans);
udf_zone_trans = NULL;
}
if (udf_zone_node != NULL) {
uma_zdestroy(udf_zone_node);
udf_zone_node = NULL;
}
if (udf_zone_ds != NULL) {
uma_zdestroy(udf_zone_ds);
udf_zone_ds = NULL;
}
return (0);
}
static int
udf_mount(struct mount *mp, struct nameidata *ndp, struct thread *td)
{
struct vnode *devvp; /* vnode of the mount device */
struct udf_mnt *imp = 0;
struct export_args *export;
struct vfsoptlist *opts;
char *fspec;
size_t size;
int error, len;
opts = mp->mnt_optnew;
if ((mp->mnt_flag & MNT_RDONLY) == 0)
return (EROFS);
/*
* No root filesystem support. Probably not a big deal, since the
* bootloader doesn't understand UDF.
*/
if (mp->mnt_flag & MNT_ROOTFS)
return (ENOTSUP);
fspec = NULL;
error = vfs_getopt(opts, "from", (void **)&fspec, &len);
if (!error && fspec[len - 1] != '\0')
return (EINVAL);
if (mp->mnt_flag & MNT_UPDATE) {
imp = VFSTOUDFFS(mp);
if (fspec == NULL) {
error = vfs_getopt(opts, "export", (void **)&export,
&len);
if (error || len != sizeof(struct export_args))
return (EINVAL);
return (vfs_export(mp, export));
}
}
/* Check that the mount device exists */
if (fspec == NULL)
return (EINVAL);
NDINIT(ndp, LOOKUP, FOLLOW, UIO_SYSSPACE, fspec, td);
if ((error = namei(ndp)))
return (error);
NDFREE(ndp, NDF_ONLY_PNBUF);
devvp = ndp->ni_vp;
if (vn_isdisk(devvp, &error) == 0) {
vrele(devvp);
return (error);
}
/* Check the access rights on the mount device */
vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY, td);
error = VOP_ACCESS(devvp, VREAD, td->td_ucred, td);
if (error)
error = suser(td);
if (error) {
vput(devvp);
return (error);
}
VOP_UNLOCK(devvp, 0, td);
if ((error = udf_mountfs(devvp, mp, td))) {
vrele(devvp);
return (error);
}
imp = VFSTOUDFFS(mp);
copystr(fspec, mp->mnt_stat.f_mntfromname, MNAMELEN - 1, &size);
bzero(mp->mnt_stat.f_mntfromname + size, MNAMELEN - size);
udf_statfs(mp, &mp->mnt_stat, td);
return 0;
};
/*
* Check the descriptor tag for both the correct id and correct checksum.
* Return zero if all is good, EINVAL if not.
*/
int
udf_checktag(struct desc_tag *tag, uint16_t id)
{
uint8_t *itag;
uint8_t i, cksum = 0;
itag = (uint8_t *)tag;
if (tag->id != id)
return (EINVAL);
for (i = 0; i < 15; i++)
cksum = cksum + itag[i];
cksum = cksum - itag[4];
if (cksum == tag->cksum)
return (0);
return (EINVAL);
}
static int
udf_mountfs(struct vnode *devvp, struct mount *mp, struct thread *td) {
struct buf *bp = NULL;
struct anchor_vdp avdp;
struct udf_mnt *udfmp = NULL;
struct part_desc *pd;
struct logvol_desc *lvd;
struct fileset_desc *fsd;
struct file_entry *root_fentry;
uint32_t sector, size, mvds_start, mvds_end;
uint32_t fsd_offset = 0;
uint16_t part_num = 0, fsd_part = 0;
int error = EINVAL, needclose = 0;
int logvol_found = 0, part_found = 0, fsd_found = 0;
int bsize;
/*
* Disallow multiple mounts of the same device. Flush the buffer
* cache for the device.
*/
if ((error = vfs_mountedon(devvp)))
return (error);
if (vcount(devvp) > 1)
return (EBUSY);
if ((error = vinvalbuf(devvp, V_SAVE, td->td_ucred, td, 0, 0)))
return (error);
vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY, td);
error = VOP_OPEN(devvp, FREAD, FSCRED, td);
VOP_UNLOCK(devvp, 0, td);
if (error)
return error;
needclose = 1;
MALLOC(udfmp, struct udf_mnt *, sizeof(struct udf_mnt), M_UDFMOUNT,
M_NOWAIT | M_ZERO);
if (udfmp == NULL) {
printf("Cannot allocate UDF mount struct\n");
error = ENOMEM;
goto bail;
}
mp->mnt_data = (qaddr_t)udfmp;
mp->mnt_stat.f_fsid.val[0] = dev2udev(devvp->v_rdev);
mp->mnt_stat.f_fsid.val[1] = mp->mnt_vfc->vfc_typenum;
mp->mnt_flag |= MNT_LOCAL;
udfmp->im_mountp = mp;
udfmp->im_dev = devvp->v_rdev;
udfmp->im_devvp = devvp;
bsize = 2048; /* XXX Should probe the media for it's size */
/*
* Get the Anchor Volume Descriptor Pointer from sector 256.
* XXX Should also check sector n - 256, n, and 512.
*/
sector = 256;
if ((error = bread(devvp, sector * btodb(bsize), bsize, NOCRED,
&bp)) != 0)
goto bail;
if ((error = udf_checktag((struct desc_tag *)bp->b_data, TAGID_ANCHOR)))
goto bail;
bcopy(bp->b_data, &avdp, sizeof(struct anchor_vdp));
brelse(bp);
bp = NULL;
/*
* Extract the Partition Descriptor and Logical Volume Descriptor
* from the Volume Descriptor Sequence.
* XXX Should we care about the partition type right now?
* XXX What about multiple partitions?
*/
mvds_start = avdp.main_vds_ex.loc;
mvds_end = mvds_start + (avdp.main_vds_ex.len - 1) / bsize;
for (sector = mvds_start; sector < mvds_end; sector++) {
if ((error = bread(devvp, sector * btodb(bsize), bsize,
NOCRED, &bp)) != 0) {
printf("Can't read sector %d of VDS\n", sector);
goto bail;
}
lvd = (struct logvol_desc *)bp->b_data;
if (!udf_checktag(&lvd->tag, TAGID_LOGVOL)) {
udfmp->bsize = lvd->lb_size;
udfmp->bmask = udfmp->bsize - 1;
udfmp->bshift = ffs(udfmp->bsize) - 1;
fsd_part = lvd->_lvd_use.fsd_loc.loc.part_num;
fsd_offset = lvd->_lvd_use.fsd_loc.loc.lb_num;
if (udf_find_partmaps(udfmp, lvd))
break;
logvol_found = 1;
}
pd = (struct part_desc *)bp->b_data;
if (!udf_checktag(&pd->tag, TAGID_PARTITION)) {
part_found = 1;
part_num = pd->part_num;
udfmp->part_len = pd->part_len;
udfmp->part_start = pd->start_loc;
}
brelse(bp);
bp = NULL;
if ((part_found) && (logvol_found))
break;
}
if (!part_found || !logvol_found) {
error = EINVAL;
goto bail;
}
if (fsd_part != part_num) {
printf("FSD does not lie within the partition!\n");
error = EINVAL;
goto bail;
}
/*
* Grab the Fileset Descriptor
* Thanks to Chuck McCrobie <mccrobie@cablespeed.com> for pointing
* me in the right direction here.
*/
sector = udfmp->part_start + fsd_offset;
if ((error = RDSECTOR(devvp, sector, udfmp->bsize, &bp)) != 0) {
printf("Cannot read sector %d of FSD\n", sector);
goto bail;
}
fsd = (struct fileset_desc *)bp->b_data;
if (!udf_checktag(&fsd->tag, TAGID_FSD)) {
fsd_found = 1;
bcopy(&fsd->rootdir_icb, &udfmp->root_icb,
sizeof(struct long_ad));
}
brelse(bp);
bp = NULL;
if (!fsd_found) {
printf("Couldn't find the fsd\n");
error = EINVAL;
goto bail;
}
/*
* Find the file entry for the root directory.
*/
sector = udfmp->root_icb.loc.lb_num + udfmp->part_start;
size = udfmp->root_icb.len;
if ((error = udf_readlblks(udfmp, sector, size, &bp)) != 0) {
printf("Cannot read sector %d\n", sector);
goto bail;
}
root_fentry = (struct file_entry *)bp->b_data;
if ((error = udf_checktag(&root_fentry->tag, TAGID_FENTRY))) {
printf("Invalid root file entry!\n");
goto bail;
}
brelse(bp);
bp = NULL;
TAILQ_INIT(&udfmp->udf_tqh);
devvp->v_rdev->si_mountpoint = mp;
mtx_init(&udfmp->hash_mtx, "udf_hash", NULL, MTX_DEF);
return 0;
bail:
if (udfmp != NULL)
FREE(udfmp, M_UDFMOUNT);
if (bp != NULL)
brelse(bp);
if (needclose)
VOP_CLOSE(devvp, FREAD, NOCRED, td);
return error;
};
static int
udf_unmount(struct mount *mp, int mntflags, struct thread *td)
{
struct udf_mnt *udfmp;
int error, flags = 0;
udfmp = VFSTOUDFFS(mp);
if (mntflags & MNT_FORCE)
flags |= FORCECLOSE;
if ((error = vflush(mp, 0, flags)))
return (error);
udfmp->im_devvp->v_rdev->si_mountpoint = NULL;
error = VOP_CLOSE(udfmp->im_devvp, FREAD, NOCRED, td);
vrele(udfmp->im_devvp);
if (udfmp->s_table != NULL)
FREE(udfmp->s_table, M_UDFSTABLE);
FREE(udfmp, M_UDFMOUNT);
mp->mnt_data = (qaddr_t)0;
mp->mnt_flag &= ~MNT_LOCAL;
return (0);
}
static int
udf_root(struct mount *mp, struct vnode **vpp)
{
struct udf_mnt *udfmp;
struct vnode *vp;
ino_t id;
int error;
udfmp = VFSTOUDFFS(mp);
id = udf_getid(&udfmp->root_icb);
error = udf_vget(mp, id, LK_EXCLUSIVE, vpp);
if (error)
return error;
vp = *vpp;
vp->v_vflag |= VV_ROOT;
udfmp->root_vp = vp;
return (0);
}
static int
udf_statfs(struct mount *mp, struct statfs *sbp, struct thread *td)
{
struct udf_mnt *udfmp;
udfmp = VFSTOUDFFS(mp);
sbp->f_bsize = udfmp->bsize;
sbp->f_iosize = udfmp->bsize;
sbp->f_blocks = udfmp->part_len;
sbp->f_bfree = 0;
sbp->f_bavail = 0;
sbp->f_files = 0;
sbp->f_ffree = 0;
if (sbp != &mp->mnt_stat) {
sbp->f_type = mp->mnt_vfc->vfc_typenum;
bcopy(mp->mnt_stat.f_mntonname, sbp->f_mntonname, MNAMELEN);
bcopy(mp->mnt_stat.f_mntfromname, sbp->f_mntfromname, MNAMELEN);
}
return 0;
}
int
udf_vget(struct mount *mp, ino_t ino, int flags, struct vnode **vpp)
{
struct buf *bp;
struct vnode *devvp;
struct udf_mnt *udfmp;
struct thread *td;
struct vnode *vp;
struct udf_node *unode;
struct file_entry *fe;
int error, sector, size;
td = curthread;
udfmp = VFSTOUDFFS(mp);
/* See if we already have this in the cache */
if ((error = udf_hashlookup(udfmp, ino, flags, vpp)) != 0)
return (error);
if (*vpp != NULL) {
return (0);
}
/*
* Allocate memory and check the tag id's before grabbing a new
* vnode, since it's hard to roll back if there is a problem.
*/
unode = uma_zalloc(udf_zone_node, M_WAITOK);
if (unode == NULL) {
printf("Cannot allocate udf node\n");
return (ENOMEM);
}
/*
* Copy in the file entry. Per the spec, the size can only be 1 block.
*/
sector = ino + udfmp->part_start;
devvp = udfmp->im_devvp;
if ((error = RDSECTOR(devvp, sector, udfmp->bsize, &bp)) != 0) {
printf("Cannot read sector %d\n", sector);
uma_zfree(udf_zone_node, unode);
return (error);
}
fe = (struct file_entry *)bp->b_data;
if (udf_checktag(&fe->tag, TAGID_FENTRY)) {
printf("Invalid file entry!\n");
uma_zfree(udf_zone_node, unode);
brelse(bp);
return (ENOMEM);
}
size = UDF_FENTRY_SIZE + fe->l_ea + fe->l_ad;
MALLOC(unode->fentry, struct file_entry *, size, M_UDFFENTRY,
M_NOWAIT | M_ZERO);
if (unode->fentry == NULL) {
printf("Cannot allocate file entry block\n");
uma_zfree(udf_zone_node, unode);
brelse(bp);
return (ENOMEM);
}
bcopy(bp->b_data, unode->fentry, size);
brelse(bp);
bp = NULL;
if ((error = udf_allocv(mp, &vp, td))) {
printf("Error from udf_allocv\n");
uma_zfree(udf_zone_node, unode);
return (error);
}
unode->i_vnode = vp;
unode->hash_id = ino;
unode->i_devvp = udfmp->im_devvp;
unode->i_dev = udfmp->im_dev;
unode->udfmp = udfmp;
vp->v_data = unode;
lockinit(&vp->v_lock, PINOD, "udfnode", 0, 0);
vp->v_vnlock = &vp->v_lock;
VREF(udfmp->im_devvp);
udf_hashins(unode);
switch (unode->fentry->icbtag.file_type) {
default:
vp->v_type = VBAD;
break;
case 4:
vp->v_type = VDIR;
break;
case 5:
vp->v_type = VREG;
break;
case 6:
vp->v_type = VBLK;
break;
case 7:
vp->v_type = VCHR;
break;
case 9:
vp->v_type = VFIFO;
break;
case 10:
vp->v_type = VSOCK;
break;
case 12:
vp->v_type = VLNK;
break;
}
*vpp = vp;
return (0);
}
struct ifid {
ushort ifid_len;
ushort ifid_pad;
int ifid_ino;
long ifid_start;
};
static int
udf_fhtovp(struct mount *mp, struct fid *fhp, struct vnode **vpp)
{
struct ifid *ifhp;
struct vnode *nvp;
int error;
ifhp = (struct ifid *)fhp;
if ((error = VFS_VGET(mp, ifhp->ifid_ino, LK_EXCLUSIVE, &nvp)) != 0) {
*vpp = NULLVP;
return (error);
}
*vpp = nvp;
return (0);
}
static int
udf_vptofh (struct vnode *vp, struct fid *fhp)
{
struct udf_node *node;
struct ifid *ifhp;
node = VTON(vp);
ifhp = (struct ifid *)fhp;
ifhp->ifid_len = sizeof(struct ifid);
ifhp->ifid_ino = node->hash_id;
return (0);
}
static int
udf_find_partmaps(struct udf_mnt *udfmp, struct logvol_desc *lvd)
{
union udf_pmap *pmap;
struct part_map_spare *pms;
struct regid *pmap_id;
struct buf *bp;
unsigned char regid_id[UDF_REGID_ID_SIZE + 1];
int i, ptype, psize, error;
for (i = 0; i < lvd->n_pm; i++) {
pmap = (union udf_pmap *)&lvd->maps[i * UDF_PMAP_SIZE];
ptype = pmap->data[0];
psize = pmap->data[1];
if (((ptype != 1) && (ptype != 2)) ||
((psize != UDF_PMAP_SIZE) && (psize != 6))) {
printf("Invalid partition map found\n");
return (1);
}
if (ptype == 1) {
/* Type 1 map. We don't care */
continue;
}
/* Type 2 map. Gotta find out the details */
pmap_id = (struct regid *)&pmap->data[4];
bzero(&regid_id[0], UDF_REGID_ID_SIZE);
bcopy(&pmap_id->id[0], &regid_id[0], UDF_REGID_ID_SIZE);
if (bcmp(&regid_id[0], "*UDF Sparable Partition",
UDF_REGID_ID_SIZE)) {
printf("Unsupported partition map: %s\n", &regid_id[0]);
return (1);
}
pms = &pmap->pms;
MALLOC(udfmp->s_table, struct udf_sparing_table *, pms->st_size,
M_UDFSTABLE, M_NOWAIT | M_ZERO);
if (udfmp->s_table == NULL)
return (ENOMEM);
/* Calculate the number of sectors per packet. */
/* XXX Logical or physical? */
udfmp->p_sectors = pms->packet_len / udfmp->bsize;
/*
* XXX If reading the first Sparing Table fails, should look
* for another table.
*/
if ((error = udf_readlblks(udfmp, pms->st_loc[0], pms->st_size,
&bp)) != 0) {
printf("Failed to read Sparing Table at sector %d\n",
pms->st_loc[0]);
return (error);
}
bcopy(bp->b_data, udfmp->s_table, pms->st_size);
brelse(bp);
if (udf_checktag(&udfmp->s_table->tag, 0)) {
printf("Invalid sparing table found\n");
return (EINVAL);
}
/* See how many valid entries there are here. The list is
* supposed to be sorted. 0xfffffff0 and higher are not valid
*/
for (i = 0; i < udfmp->s_table->rt_l; i++) {
udfmp->s_table_entries = i;
if (udfmp->s_table->entries[i].org >= 0xfffffff0)
break;
}
}
return (0);
}