/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 2004-2008 Silicon Graphics, Inc. All rights reserved.
*/
/*
* External Cross Partition (XP) structures and defines.
*/
#ifndef _DRIVERS_MISC_SGIXP_XP_H
#define _DRIVERS_MISC_SGIXP_XP_H
#include <linux/cache.h>
#include <linux/hardirq.h>
#include <linux/mutex.h>
#include <asm/sn/types.h>
#include <asm/sn/bte.h>
#ifdef USE_DBUG_ON
#define DBUG_ON(condition) BUG_ON(condition)
#else
#define DBUG_ON(condition)
#endif
/*
* Define the maximum number of logically defined partitions the system
* can support. It is constrained by the maximum number of hardware
* partitionable regions. The term 'region' in this context refers to the
* minimum number of nodes that can comprise an access protection grouping.
* The access protection is in regards to memory, IPI and IOI.
*
* The maximum number of hardware partitionable regions is equal to the
* maximum number of nodes in the entire system divided by the minimum number
* of nodes that comprise an access protection grouping.
*/
#define XP_MAX_PARTITIONS 64
/*
* Define the number of u64s required to represent all the C-brick nasids
* as a bitmap. The cross-partition kernel modules deal only with
* C-brick nasids, thus the need for bitmaps which don't account for
* odd-numbered (non C-brick) nasids.
*/
#define XP_MAX_PHYSNODE_ID (MAX_NUMALINK_NODES / 2)
#define XP_NASID_MASK_BYTES ((XP_MAX_PHYSNODE_ID + 7) / 8)
#define XP_NASID_MASK_WORDS ((XP_MAX_PHYSNODE_ID + 63) / 64)
/*
* Wrapper for bte_copy() that should it return a failure status will retry
* the bte_copy() once in the hope that the failure was due to a temporary
* aberration (i.e., the link going down temporarily).
*
* src - physical address of the source of the transfer.
* vdst - virtual address of the destination of the transfer.
* len - number of bytes to transfer from source to destination.
* mode - see bte_copy() for definition.
* notification - see bte_copy() for definition.
*
* Note: xp_bte_copy() should never be called while holding a spinlock.
*/
static inline bte_result_t
xp_bte_copy(u64 src, u64 vdst, u64 len, u64 mode, void *notification)
{
bte_result_t ret;
u64 pdst = ia64_tpa(vdst);
/*
* Ensure that the physically mapped memory is contiguous.
*
* We do this by ensuring that the memory is from region 7 only.
* If the need should arise to use memory from one of the other
* regions, then modify the BUG_ON() statement to ensure that the
* memory from that region is always physically contiguous.
*/
BUG_ON(REGION_NUMBER(vdst) != RGN_KERNEL);
ret = bte_copy(src, pdst, len, mode, notification);
if ((ret != BTE_SUCCESS) && BTE_ERROR_RETRY(ret)) {
if (!in_interrupt())
cond_resched();
ret = bte_copy(src, pdst, len, mode, notification);
}
return ret;
}
/*
* XPC establishes channel connections between the local partition and any
* other partition that is currently up. Over these channels, kernel-level
* `users' can communicate with their counterparts on the other partitions.
*
* The maxinum number of channels is limited to eight. For performance reasons,
* the internal cross partition structures require sixteen bytes per channel,
* and eight allows all of this interface-shared info to fit in one cache line.
*
* XPC_NCHANNELS reflects the total number of channels currently defined.
* If the need for additional channels arises, one can simply increase
* XPC_NCHANNELS accordingly. If the day should come where that number
* exceeds the MAXIMUM number of channels allowed (eight), then one will need
* to make changes to the XPC code to allow for this.
*/
#define XPC_MEM_CHANNEL 0 /* memory channel number */
#define XPC_NET_CHANNEL 1 /* network channel number */
#define XPC_NCHANNELS 2 /* #of defined channels */
#define XPC_MAX_NCHANNELS 8 /* max #of channels allowed */
#if XPC_NCHANNELS > XPC_MAX_NCHANNELS
#error XPC_NCHANNELS exceeds MAXIMUM allowed.
#endif
/*
* The format of an XPC message is as follows:
*
* +-------+--------------------------------+
* | flags |////////////////////////////////|
* +-------+--------------------------------+
* | message # |
* +----------------------------------------+
* | payload (user-defined message) |
* | |
* :
* | |
* +----------------------------------------+
*
* The size of the payload is defined by the user via xpc_connect(). A user-
* defined message resides in the payload area.
*
* The user should have no dealings with the message header, but only the
* message's payload. When a message entry is allocated (via xpc_allocate())
* a pointer to the payload area is returned and not the actual beginning of
* the XPC message. The user then constructs a message in the payload area
* and passes that pointer as an argument on xpc_send() or xpc_send_notify().
*
* The size of a message entry (within a message queue) must be a cacheline
* sized multiple in order to facilitate the BTE transfer of messages from one
* message queue to another. A macro, XPC_MSG_SIZE(), is provided for the user
* that wants to fit as many msg entries as possible in a given memory size
* (e.g. a memory page).
*/
struct xpc_msg {
u8 flags; /* FOR XPC INTERNAL USE ONLY */
u8 reserved[7]; /* FOR XPC INTERNAL USE ONLY */
s64 number; /* FOR XPC INTERNAL USE ONLY */
u64 payload; /* user defined portion of message */
};
#define XPC_MSG_PAYLOAD_OFFSET (u64) (&((struct xpc_msg *)0)->payload)
#define XPC_MSG_SIZE(_payload_size) \
L1_CACHE_ALIGN(XPC_MSG_PAYLOAD_OFFSET + (_payload_size))
/*
* Define the return values and values passed to user's callout functions.
* (It is important to add new value codes at the end just preceding
* xpUnknownReason, which must have the highest numerical value.)
*/
enum xp_retval {
xpSuccess = 0,
xpNotConnected, /* 1: channel is not connected */
xpConnected, /* 2: channel connected (opened) */
xpRETIRED1, /* 3: (formerly xpDisconnected) */
xpMsgReceived, /* 4: message received */
xpMsgDelivered, /* 5: message delivered and acknowledged */
xpRETIRED2, /* 6: (formerly xpTransferFailed) */
xpNoWait, /* 7: operation would require wait */
xpRetry, /* 8: retry operation */
xpTimeout, /* 9: timeout in xpc_allocate_msg_wait() */
xpInterrupted, /* 10: interrupted wait */
xpUnequalMsgSizes, /* 11: message size disparity between sides */
xpInvalidAddress, /* 12: invalid address */
xpNoMemory, /* 13: no memory available for XPC structures */
xpLackOfResources, /* 14: insufficient resources for operation */
xpUnregistered, /* 15: channel is not registered */
xpAlreadyRegistered, /* 16: channel is already registered */
xpPartitionDown, /* 17: remote partition is down */
xpNotLoaded, /* 18: XPC module is not loaded */
xpUnloading, /* 19: this side is unloading XPC module */
xpBadMagic, /* 20: XPC MAGIC string not found */
xpReactivating, /* 21: remote partition was reactivated */
xpUnregistering, /* 22: this side is unregistering channel */
xpOtherUnregistering, /* 23: other side is unregistering channel */
xpCloneKThread, /* 24: cloning kernel thread */
xpCloneKThreadFailed, /* 25: cloning kernel thread failed */
xpNoHeartbeat, /* 26: remote partition has no heartbeat */
xpPioReadError, /* 27: PIO read error */
xpPhysAddrRegFailed, /* 28: registration of phys addr range failed */
xpRETIRED3, /* 29: (formerly xpBteDirectoryError) */
xpRETIRED4, /* 30: (formerly xpBtePoisonError) */
xpRETIRED5, /* 31: (formerly xpBteWriteError) */
xpRETIRED6, /* 32: (formerly xpBteAccessError) */
xpRETIRED7, /* 33: (formerly xpBtePWriteError) */
xpRETIRED8, /* 34: (formerly xpBtePReadError) */
xpRETIRED9, /* 35: (formerly xpBteTimeOutError) */
xpRETIRED10, /* 36: (formerly xpBteXtalkError) */
xpRETIRED11, /* 37: (formerly xpBteNotAvailable) */
xpRETIRED12, /* 38: (formerly xpBteUnmappedError) */
xpBadVersion, /* 39: bad version number */
xpVarsNotSet, /* 40: the XPC variables are not set up */
xpNoRsvdPageAddr, /* 41: unable to get rsvd page's phys addr */
xpInvalidPartid, /* 42: invalid partition ID */
xpLocalPartid, /* 43: local partition ID */
xpOtherGoingDown, /* 44: other side going down, reason unknown */
xpSystemGoingDown, /* 45: system is going down, reason unknown */
xpSystemHalt, /* 46: system is being halted */
xpSystemReboot, /* 47: system is being rebooted */
xpSystemPoweroff, /* 48: system is being powered off */
xpDisconnecting, /* 49: channel disconnecting (closing) */
xpOpenCloseError, /* 50: channel open/close protocol error */
xpDisconnected, /* 51: channel disconnected (closed) */
xpBteCopyError, /* 52: bte_copy() returned error */
xpUnknownReason /* 53: unknown reason - must be last in enum */
};
/*
* Define the callout function type used by XPC to update the user on
* connection activity and state changes via the user function registered
* by xpc_connect().
*
* Arguments:
*
* reason - reason code.
* partid - partition ID associated with condition.
* ch_number - channel # associated with condition.
* data - pointer to optional data.
* key - pointer to optional user-defined value provided as the "key"
* argument to xpc_connect().
*
* A reason code of xpConnected indicates that a connection has been
* established to the specified partition on the specified channel. The data
* argument indicates the max number of entries allowed in the message queue.
*
* A reason code of xpMsgReceived indicates that a XPC message arrived from
* the specified partition on the specified channel. The data argument
* specifies the address of the message's payload. The user must call
* xpc_received() when finished with the payload.
*
* All other reason codes indicate failure. The data argmument is NULL.
* When a failure reason code is received, one can assume that the channel
* is not connected.
*/
typedef void (*xpc_channel_func) (enum xp_retval reason, short partid,
int ch_number, void *data, void *key);
/*
* Define the callout function type used by XPC to notify the user of
* messages received and delivered via the user function registered by
* xpc_send_notify().
*
* Arguments:
*
* reason - reason code.
* partid - partition ID associated with condition.
* ch_number - channel # associated with condition.
* key - pointer to optional user-defined value provided as the "key"
* argument to xpc_send_notify().
*
* A reason code of xpMsgDelivered indicates that the message was delivered
* to the intended recipient and that they have acknowledged its receipt by
* calling xpc_received().
*
* All other reason codes indicate failure.
*/
typedef void (*xpc_notify_func) (enum xp_retval reason, short partid,
int ch_number, void *key);
/*
* The following is a registration entry. There is a global array of these,
* one per channel. It is used to record the connection registration made
* by the users of XPC. As long as a registration entry exists, for any
* partition that comes up, XPC will attempt to establish a connection on
* that channel. Notification that a connection has been made will occur via
* the xpc_channel_func function.
*
* The 'func' field points to the function to call when aynchronous
* notification is required for such events as: a connection established/lost,
* or an incoming message received, or an error condition encountered. A
* non-NULL 'func' field indicates that there is an active registration for
* the channel.
*/
struct xpc_registration {
struct mutex mutex;
xpc_channel_func func; /* function to call */
void *key; /* pointer to user's key */
u16 nentries; /* #of msg entries in local msg queue */
u16 msg_size; /* message queue's message size */
u32 assigned_limit; /* limit on #of assigned kthreads */
u32 idle_limit; /* limit on #of idle kthreads */
} ____cacheline_aligned;
#define XPC_CHANNEL_REGISTERED(_c) (xpc_registrations[_c].func != NULL)
/* the following are valid xpc_allocate() flags */
#define XPC_WAIT 0 /* wait flag */
#define XPC_NOWAIT 1 /* no wait flag */
struct xpc_interface {
void (*connect) (int);
void (*disconnect) (int);
enum xp_retval (*allocate) (short, int, u32, void **);
enum xp_retval (*send) (short, int, void *);
enum xp_retval (*send_notify) (short, int, void *,
xpc_notify_func, void *);
void (*received) (short, int, void *);
enum xp_retval (*partid_to_nasids) (short, void *);
};
extern struct xpc_interface xpc_interface;
extern void xpc_set_interface(void (*)(int),
void (*)(int),
enum xp_retval (*)(short, int, u32, void **),
enum xp_retval (*)(short, int, void *),
enum xp_retval (*)(short, int, void *,
xpc_notify_func, void *),
void (*)(short, int, void *),
enum xp_retval (*)(short, void *));
extern void xpc_clear_interface(void);
extern enum xp_retval xpc_connect(int, xpc_channel_func, void *, u16,
u16, u32, u32);
extern void xpc_disconnect(int);
static inline enum xp_retval
xpc_allocate(short partid, int ch_number, u32 flags, void **payload)
{
return xpc_interface.allocate(partid, ch_number, flags, payload);
}
static inline enum xp_retval
xpc_send(short partid, int ch_number, void *payload)
{
return xpc_interface.send(partid, ch_number, payload);
}
static inline enum xp_retval
xpc_send_notify(short partid, int ch_number, void *payload,
xpc_notify_func func, void *key)
{
return xpc_interface.send_notify(partid, ch_number, payload, func, key);
}
static inline void
xpc_received(short partid, int ch_number, void *payload)
{
return xpc_interface.received(partid, ch_number, payload);
}
static inline enum xp_retval
xpc_partid_to_nasids(short partid, void *nasids)
{
return xpc_interface.partid_to_nasids(partid, nasids);
}
extern u64 xp_nofault_PIOR_target;
extern int xp_nofault_PIOR(void *);
extern int xp_error_PIOR(void);
#endif /* _DRIVERS_MISC_SGIXP_XP_H */
