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[PATCH] IB/ipath: fix a bug that results in addresses near 0 being written via DMA

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We can't tell for sure if any packets are in the infinipath receive buffer
when we shut down a chip port.  Normally this is taken care of by orderly
shutdown, but when processes are terminated, or sending process has a bug, we
can continue to receive packets.  So rather than writing zero to the address
registers for the closing port, we point it at a dummy memory.

Signed-off-by: Dave Olson <dave.olson@qlogic.com>
Signed-off-by: Bryan O'Sullivan <bryan.osullivan@qlogic.com>
Cc: "Michael S. Tsirkin" <mst@mellanox.co.il>
Cc: Roland Dreier <rolandd@cisco.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Bryan O'Sullivan
2006-07-01 04:36:15 -07:00
committed by Linus Torvalds
parent 6d8e9dd050
commit 35783ec07c
4 changed files with 59 additions and 25 deletions
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59
drivers/infiniband/hw/ipath/ipath_file_ops.c
View File

@ -1486,42 +1486,51 @@ static int ipath_close(struct inode *in, struct file *fp)
}
if (dd->ipath_kregbase) {
ipath_write_kreg_port(
dd, dd->ipath_kregs->kr_rcvhdrtailaddr,
port, 0ULL);
ipath_write_kreg_port(
dd, dd->ipath_kregs->kr_rcvhdraddr,
pd->port_port, 0);
int i;
/* atomically clear receive enable port. */
clear_bit(INFINIPATH_R_PORTENABLE_SHIFT + port,
&dd->ipath_rcvctrl);
ipath_write_kreg( dd, dd->ipath_kregs->kr_rcvctrl,
dd->ipath_rcvctrl);
/* and read back from chip to be sure that nothing
* else is in flight when we do the rest */
(void)ipath_read_kreg64(dd, dd->ipath_kregs->kr_scratch);
/* clean up the pkeys for this port user */
ipath_clean_part_key(pd, dd);
if (port < dd->ipath_cfgports) {
int i = dd->ipath_pbufsport * (port - 1);
ipath_disarm_piobufs(dd, i, dd->ipath_pbufsport);
/* atomically clear receive enable port. */
clear_bit(INFINIPATH_R_PORTENABLE_SHIFT + port,
&dd->ipath_rcvctrl);
ipath_write_kreg(
dd,
dd->ipath_kregs->kr_rcvctrl,
dd->ipath_rcvctrl);
/*
* be paranoid, and never write 0's to these, just use an
* unused part of the port 0 tail page. Of course,
* rcvhdraddr points to a large chunk of memory, so this
* could still trash things, but at least it won't trash
* page 0, and by disabling the port, it should stop "soon",
* even if a packet or two is in already in flight after we
* disabled the port.
*/
ipath_write_kreg_port(dd,
dd->ipath_kregs->kr_rcvhdrtailaddr, port,
dd->ipath_dummy_hdrq_phys);
ipath_write_kreg_port(dd, dd->ipath_kregs->kr_rcvhdraddr,
pd->port_port, dd->ipath_dummy_hdrq_phys);
if (dd->ipath_pageshadow)
unlock_expected_tids(pd);
ipath_stats.sps_ports--;
ipath_cdbg(PROC, "%s[%u] closed port %u:%u\n",
pd->port_comm, pd->port_pid,
dd->ipath_unit, port);
}
i = dd->ipath_pbufsport * (port - 1);
ipath_disarm_piobufs(dd, i, dd->ipath_pbufsport);
if (dd->ipath_pageshadow)
unlock_expected_tids(pd);
ipath_stats.sps_ports--;
ipath_cdbg(PROC, "%s[%u] closed port %u:%u\n",
pd->port_comm, pd->port_pid,
dd->ipath_unit, port);
dd->ipath_f_clear_tids(dd, pd->port_port);
}
pd->port_cnt = 0;
pd->port_pid = 0;
dd->ipath_f_clear_tids(dd, pd->port_port);
dd->ipath_pd[pd->port_port] = NULL; /* before releasing mutex */
mutex_unlock(&ipath_mutex);
ipath_free_pddata(dd, pd); /* after releasing the mutex */