/*
* Return buffer with the contents of block "offset" from the beginning of
* directory "ip". If "res" is non-zero, fill it in with a pointer to the
* remaining space in the directory.
*/
int
cd9660_blkatoff(struct vnode *vp, off_t offset, char **res, struct buf **bpp)
{
struct iso_node *ip;
struct iso_mnt *imp;
struct buf *bp;
daddr_t lbn;
int bsize, error;
ip = VTOI(vp);
imp = ip->i_mnt;
lbn = cd9660_lblkno(imp, offset);
bsize = cd9660_blksize(imp, ip, lbn);
if ((error = bread(vp, lbn, bsize, NOCRED, 0, &bp)) != 0) {
*bpp = NULL;
return (error);
}
if (res)
*res = (char *)bp->b_data + cd9660_blkoff(imp, offset);
*bpp = bp;
return (0);
}
/*
* Vnode op for reading.
*/
int
cd9660_read(void *v)
{
struct vop_read_args /* {
struct vnode *a_vp;
struct uio *a_uio;
int a_ioflag;
kauth_cred_t a_cred;
} */ *ap = v;
struct vnode *vp = ap->a_vp;
struct uio *uio = ap->a_uio;
struct iso_node *ip = VTOI(vp);
struct iso_mnt *imp;
struct buf *bp;
daddr_t lbn, rablock;
off_t diff;
int rasize, error = 0;
long size, n, on;
if (uio->uio_resid == 0)
return (0);
if (uio->uio_offset < 0)
return (EINVAL);
if (uio->uio_offset >= ip->i_size)
return 0;
ip->i_flag |= IN_ACCESS;
imp = ip->i_mnt;
if (vp->v_type == VREG) {
const int advice = IO_ADV_DECODE(ap->a_ioflag);
error = 0;
while (uio->uio_resid > 0) {
vsize_t bytelen = MIN(ip->i_size - uio->uio_offset,
uio->uio_resid);
if (bytelen == 0)
break;
error = ubc_uiomove(&vp->v_uobj, uio, bytelen, advice,
UBC_READ | UBC_PARTIALOK | UBC_UNMAP_FLAG(vp));
if (error)
break;
}
goto out;
}
do {
lbn = cd9660_lblkno(imp, uio->uio_offset);
on = cd9660_blkoff(imp, uio->uio_offset);
n = MIN(imp->logical_block_size - on, uio->uio_resid);
diff = (off_t)ip->i_size - uio->uio_offset;
if (diff <= 0)
return (0);
if (diff < n)
n = diff;
size = cd9660_blksize(imp, ip, lbn);
rablock = lbn + 1;
if (cd9660_lblktosize(imp, rablock) < ip->i_size) {
rasize = cd9660_blksize(imp, ip, rablock);
error = breadn(vp, lbn, size, &rablock,
&rasize, 1, NOCRED, 0, &bp);
} else {
error = bread(vp, lbn, size, NOCRED, 0, &bp);
}
if (error) {
return (error);
}
n = MIN(n, size - bp->b_resid);
error = uiomove((char *)bp->b_data + on, (int)n, uio);
brelse(bp, 0);
} while (error == 0 && uio->uio_resid > 0 && n != 0);
out:
return (error);
}
