Extend m_copyback() to support unmapped mbufs.
Reviewed by: gallatin, markj Sponsored by: Netflix Differential Revision: https://reviews.freebsd.org/D30133
This commit is contained in:
parent
3c7a01d773
commit
3f9dac85cc
@ -1139,6 +1139,29 @@ m_devget(char *buf, int totlen, int off, struct ifnet *ifp,
|
||||
return (top);
|
||||
}
|
||||
|
||||
static void
|
||||
m_copytounmapped(const struct mbuf *m, int off, int len, c_caddr_t cp)
|
||||
{
|
||||
struct iovec iov;
|
||||
struct uio uio;
|
||||
int error;
|
||||
|
||||
KASSERT(off >= 0, ("m_copytounmapped: negative off %d", off));
|
||||
KASSERT(len >= 0, ("m_copytounmapped: negative len %d", len));
|
||||
KASSERT(off < m->m_len, ("m_copytounmapped: len exceeds mbuf length"));
|
||||
iov.iov_base = __DECONST(caddr_t, cp);
|
||||
iov.iov_len = len;
|
||||
uio.uio_resid = len;
|
||||
uio.uio_iov = &iov;
|
||||
uio.uio_segflg = UIO_SYSSPACE;
|
||||
uio.uio_iovcnt = 1;
|
||||
uio.uio_offset = 0;
|
||||
uio.uio_rw = UIO_WRITE;
|
||||
error = m_unmappedtouio(m, off, &uio, len);
|
||||
KASSERT(error == 0, ("m_unmappedtouio failed: off %d, len %d", off,
|
||||
len));
|
||||
}
|
||||
|
||||
/*
|
||||
* Copy data from a buffer back into the indicated mbuf chain,
|
||||
* starting "off" bytes from the beginning, extending the mbuf
|
||||
@ -1172,6 +1195,9 @@ m_copyback(struct mbuf *m0, int off, int len, c_caddr_t cp)
|
||||
M_TRAILINGSPACE(m));
|
||||
}
|
||||
mlen = min (m->m_len - off, len);
|
||||
if ((m->m_flags & M_EXTPG) != 0)
|
||||
m_copytounmapped(m, off, mlen, cp);
|
||||
else
|
||||
bcopy(cp, off + mtod(m, caddr_t), (u_int)mlen);
|
||||
cp += mlen;
|
||||
len -= mlen;
|
||||
@ -1870,7 +1896,7 @@ m_uiotombuf(struct uio *uio, int how, int len, int align, int flags)
|
||||
}
|
||||
|
||||
/*
|
||||
* Copy data from an unmapped mbuf into a uio limited by len if set.
|
||||
* Copy data to/from an unmapped mbuf into a uio limited by len if set.
|
||||
*/
|
||||
int
|
||||
m_unmappedtouio(const struct mbuf *m, int m_off, struct uio *uio, int len)
|
||||
|
Loading…
Reference in New Issue
Block a user