/*
* File table vnode read routine.
*/
static int
vn_read(file_t *fp, off_t *offset, struct uio *uio, kauth_cred_t cred,
int flags)
{
struct vnode *vp = (struct vnode *)fp->f_data;
int error, ioflag, fflag;
size_t count;
ioflag = IO_ADV_ENCODE(fp->f_advice);
fflag = fp->f_flag;
if (fflag & FNONBLOCK)
ioflag |= IO_NDELAY;
if ((fflag & (FFSYNC | FRSYNC)) == (FFSYNC | FRSYNC))
ioflag |= IO_SYNC;
if (fflag & FALTIO)
ioflag |= IO_ALTSEMANTICS;
if (fflag & FDIRECT)
ioflag |= IO_DIRECT;
vn_lock(vp, LK_SHARED | LK_RETRY);
uio->uio_offset = *offset;
count = uio->uio_resid;
error = VOP_READ(vp, uio, ioflag, cred);
if (flags & FOF_UPDATE_OFFSET)
*offset += count - uio->uio_resid;
VOP_UNLOCK(vp);
return (error);
}
/*
* File table vnode write routine.
*/
static int
vn_write(file_t *fp, off_t *offset, struct uio *uio, kauth_cred_t cred,
int flags)
{
struct vnode *vp = (struct vnode *)fp->f_data;
int error, ioflag, fflag;
size_t count;
ioflag = IO_ADV_ENCODE(fp->f_advice) | IO_UNIT;
fflag = fp->f_flag;
if (vp->v_type == VREG && (fflag & O_APPEND))
ioflag |= IO_APPEND;
if (fflag & FNONBLOCK)
ioflag |= IO_NDELAY;
if (fflag & FFSYNC ||
(vp->v_mount && (vp->v_mount->mnt_flag & MNT_SYNCHRONOUS)))
ioflag |= IO_SYNC;
else if (fflag & FDSYNC)
ioflag |= IO_DSYNC;
if (fflag & FALTIO)
ioflag |= IO_ALTSEMANTICS;
if (fflag & FDIRECT)
ioflag |= IO_DIRECT;
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
uio->uio_offset = *offset;
count = uio->uio_resid;
if ((error = enforce_rlimit_fsize(vp, uio, ioflag)) != 0)
goto out;
error = VOP_WRITE(vp, uio, ioflag, cred);
if (flags & FOF_UPDATE_OFFSET) {
if (ioflag & IO_APPEND) {
/*
* SUSv3 describes behaviour for count = 0 as following:
* "Before any action ... is taken, and if nbyte is zero
* and the file is a regular file, the write() function
* ... in the absence of errors ... shall return zero
* and have no other results."
*/
if (count)
*offset = uio->uio_offset;
} else
*offset += count - uio->uio_resid;
}
out:
VOP_UNLOCK(vp);
return (error);
}
/*
* Handes the read/write request given in 'bp' using the vnode's VOP_READ
* and VOP_WRITE operations.
*
* 'obp' is a pointer to the original request fed to the vnd device.
*/
static void
handle_with_rdwr(struct vnd_softc *vnd, const struct buf *obp, struct buf *bp)
{
bool doread;
off_t offset;
size_t len, resid;
struct vnode *vp;
doread = bp->b_flags & B_READ;
offset = obp->b_rawblkno * vnd->sc_dkdev.dk_label->d_secsize;
len = bp->b_bcount;
vp = vnd->sc_vp;
#if defined(DEBUG)
if (vnddebug & VDB_IO)
printf("vnd (rdwr): vp %p, %s, rawblkno 0x%" PRIx64
", secsize %d, offset %" PRIu64
", bcount %d\n",
vp, doread ? "read" : "write", obp->b_rawblkno,
vnd->sc_dkdev.dk_label->d_secsize, offset,
bp->b_bcount);
#endif
/* Issue the read or write operation. */
bp->b_error =
vn_rdwr(doread ? UIO_READ : UIO_WRITE,
vp, bp->b_data, len, offset, UIO_SYSSPACE,
IO_ADV_ENCODE(POSIX_FADV_NOREUSE), vnd->sc_cred, &resid, NULL);
bp->b_resid = resid;
mutex_enter(vp->v_interlock);
(void) VOP_PUTPAGES(vp, 0, 0,
PGO_ALLPAGES | PGO_CLEANIT | PGO_FREE | PGO_SYNCIO);
/* We need to increase the number of outputs on the vnode if
* there was any write to it. */
if (!doread) {
mutex_enter(vp->v_interlock);
vp->v_numoutput++;
mutex_exit(vp->v_interlock);
}
biodone(bp);
}
/*
* Read/write clusters from/to backing store.
* For persistent snapshots must be called with cl == 0. off is the
* offset into the snapshot.
*/
static int
fss_bs_io(struct fss_softc *sc, fss_io_type rw,
u_int32_t cl, off_t off, int len, void *data)
{
int error;
off += FSS_CLTOB(sc, cl);
vn_lock(sc->sc_bs_vp, LK_EXCLUSIVE|LK_RETRY);
error = vn_rdwr((rw == FSS_READ ? UIO_READ : UIO_WRITE), sc->sc_bs_vp,
data, len, off, UIO_SYSSPACE,
IO_ADV_ENCODE(POSIX_FADV_NOREUSE) | IO_NODELOCKED,
sc->sc_bs_lwp->l_cred, NULL, NULL);
if (error == 0) {
mutex_enter(sc->sc_bs_vp->v_interlock);
error = VOP_PUTPAGES(sc->sc_bs_vp, trunc_page(off),
round_page(off+len), PGO_CLEANIT | PGO_FREE | PGO_SYNCIO);
}
VOP_UNLOCK(sc->sc_bs_vp);
return error;
}
