Revision aa76042a016474775ccd187c068669148c30c3bb authored by James Hogan on 27 May 2016, 21:25:23 UTC, committed by Ralf Baechle on 28 May 2016, 10:35:11 UTC
The Hardware page Table Walker (HTW) is being misconfigured on 64-bit
kernels. The PWSize.PS (pointer size) bit determines whether pointers
within directories are loaded as 32-bit or 64-bit addresses, but was
never being set to 1 for 64-bit kernels where the unsigned long in pgd_t
is 64-bits wide.
This actually reduces rather than improves performance when the HTW is
enabled on P6600 since the HTW is initiated lots, but walks are all
aborted due I think to bad intermediate pointers.
Since we were already taking the width of the PTEs into account by
setting PWSize.PTEW, which is the left shift applied to the page table
index *in addition to* the native pointer size, we also need to reduce
PTEW by 1 when PS=1. This is done by calculating PTEW based on the
relative size of pte_t compared to pgd_t.
Finally in order for the HTW to be used when PS=1, the appropriate
XK/XS/XU bits corresponding to the different 64-bit segments need to be
set in PWCtl. We enable only XU for now to enable walking for XUSeg.
Supporting walking for XKSeg would be a bit more involved so is left for
a future patch. It would either require the use of a per-CPU top level
base directory if supported by the HTW (a bit like pgd_current but with
a second entry pointing at swapper_pg_dir), or the HTW would prepend bit
63 of the address to the global directory index which doesn't really
match how we split user and kernel page directories.
Fixes: cab25bc7537b ("MIPS: Extend hardware table walking support to MIPS64")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/13364/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
1 parent 6446e6c
rfc1002pdu.h
/*
* fs/cifs/rfc1002pdu.h
*
* Protocol Data Unit definitions for RFC 1001/1002 support
*
* Copyright (c) International Business Machines Corp., 2004
* Author(s): Steve French (sfrench@us.ibm.com)
*
* This library is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published
* by the Free Software Foundation; either version 2.1 of the License, or
* (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
* the GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
/* NB: unlike smb/cifs packets, the RFC1002 structures are big endian */
/* RFC 1002 session packet types */
#define RFC1002_SESSION_MESSAGE 0x00
#define RFC1002_SESSION_REQUEST 0x81
#define RFC1002_POSITIVE_SESSION_RESPONSE 0x82
#define RFC1002_NEGATIVE_SESSION_RESPONSE 0x83
#define RFC1002_RETARGET_SESSION_RESPONSE 0x84
#define RFC1002_SESSION_KEEP_ALIVE 0x85
/* RFC 1002 flags (only one defined */
#define RFC1002_LENGTH_EXTEND 0x80 /* high order bit of length (ie +64K) */
struct rfc1002_session_packet {
__u8 type;
__u8 flags;
__u16 length;
union {
struct {
__u8 called_len;
__u8 called_name[32];
__u8 scope1; /* null */
__u8 calling_len;
__u8 calling_name[32];
__u8 scope2; /* null */
} __attribute__((packed)) session_req;
struct {
__u32 retarget_ip_addr;
__u16 port;
} __attribute__((packed)) retarget_resp;
__u8 neg_ses_resp_error_code;
/* POSITIVE_SESSION_RESPONSE packet does not include trailer.
SESSION_KEEP_ALIVE packet also does not include a trailer.
Trailer for the SESSION_MESSAGE packet is SMB/CIFS header */
} __attribute__((packed)) trailer;
} __attribute__((packed));
/* Negative Session Response error codes */
#define RFC1002_NOT_LISTENING_CALLED 0x80 /* not listening on called name */
#define RFC1002_NOT_LISTENING_CALLING 0x81 /* not listening on calling name */
#define RFC1002_NOT_PRESENT 0x82 /* called name not present */
#define RFC1002_INSUFFICIENT_RESOURCE 0x83
#define RFC1002_UNSPECIFIED_ERROR 0x8F
/* RFC 1002 Datagram service packets are not defined here as they
are not needed for the network filesystem client unless we plan on
implementing broadcast resolution of the server ip address (from
server netbios name). Currently server names are resolved only via DNS
(tcp name) or ip address or an /etc/hosts equivalent mapping to ip address.*/
#define DEFAULT_CIFS_CALLED_NAME "*SMBSERVER "
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