/*
* SN Platform GRU Driver
*
* GRU DRIVER TABLES, MACROS, externs, etc
*
* Copyright (c) 2008 Silicon Graphics, Inc. All Rights Reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#ifndef __GRUTABLES_H__
#define __GRUTABLES_H__
/*
* GRU Chiplet:
* The GRU is a user addressible memory accelerator. It provides
* several forms of load, store, memset, bcopy instructions. In addition, it
* contains special instructions for AMOs, sending messages to message
* queues, etc.
*
* The GRU is an integral part of the node controller. It connects
* directly to the cpu socket. In its current implementation, there are 2
* GRU chiplets in the node controller on each blade (~node).
*
* The entire GRU memory space is fully coherent and cacheable by the cpus.
*
* Each GRU chiplet has a physical memory map that looks like the following:
*
* +-----------------+
* |/////////////////|
* |/////////////////|
* |/////////////////|
* |/////////////////|
* |/////////////////|
* |/////////////////|
* |/////////////////|
* |/////////////////|
* +-----------------+
* | system control |
* +-----------------+ _______ +-------------+
* |/////////////////| / | |
* |/////////////////| / | |
* |/////////////////| / | instructions|
* |/////////////////| / | |
* |/////////////////| / | |
* |/////////////////| / |-------------|
* |/////////////////| / | |
* +-----------------+ | |
* | context 15 | | data |
* +-----------------+ | |
* | ...... | \ | |
* +-----------------+ \____________ +-------------+
* | context 1 |
* +-----------------+
* | context 0 |
* +-----------------+
*
* Each of the "contexts" is a chunk of memory that can be mmaped into user
* space. The context consists of 2 parts:
*
* - an instruction space that can be directly accessed by the user
* to issue GRU instructions and to check instruction status.
*
* - a data area that acts as normal RAM.
*
* User instructions contain virtual addresses of data to be accessed by the
* GRU. The GRU contains a TLB that is used to convert these user virtual
* addresses to physical addresses.
*
* The "system control" area of the GRU chiplet is used by the kernel driver
* to manage user contexts and to perform functions such as TLB dropin and
* purging.
*
* One context may be reserved for the kernel and used for cross-partition
* communication. The GRU will also be used to asynchronously zero out
* large blocks of memory (not currently implemented).
*
*
* Tables:
*
* VDATA-VMA Data - Holds a few parameters. Head of linked list of
* GTS tables for threads using the GSEG
* GTS - Gru Thread State - contains info for managing a GSEG context. A
* GTS is allocated for each thread accessing a
* GSEG.
* GTD - GRU Thread Data - contains shadow copy of GRU data when GSEG is
* not loaded into a GRU
* GMS - GRU Memory Struct - Used to manage TLB shootdowns. Tracks GRUs
* where a GSEG has been loaded. Similar to
* an mm_struct but for GRU.
*
* GS - GRU State - Used to manage the state of a GRU chiplet
* BS - Blade State - Used to manage state of all GRU chiplets
* on a blade
*
*
* Normal task tables for task using GRU.
* - 2 threads in process
* - 2 GSEGs open in process
* - GSEG1 is being used by both threads
* - GSEG2 is used only by thread 2
*
* task -->|
* task ---+---> mm ->------ (notifier) -------+-> gms
* | |
* |--> vma -> vdata ---> gts--->| GSEG1 (thread1)
* | | |
* | +-> gts--->| GSEG1 (thread2)
* | |
* |--> vma -> vdata ---> gts--->| GSEG2 (thread2)
* .
* .
*
* GSEGs are marked DONTCOPY on fork
*
* At open
* file.private_data -> NULL
*
* At mmap,
* vma -> vdata
*
* After gseg reference
* vma -> vdata ->gts
*
* After fork
* parent
* vma -> vdata -> gts
* child
* (vma is not copied)
*
*/
#include <linux/rmap.h>
#include <linux/interrupt.h>
#include <linux/mutex.h>
#include <linux/wait.h>
#include <linux/mmu_notifier.h>
#include "gru.h"
#include "grulib.h"
#include "gruhandles.h"
extern struct gru_stats_s gru_stats;
extern struct gru_blade_state *gru_base[];
extern unsigned long gru_start_paddr, gru_end_paddr;
extern void *gru_start_vaddr;
extern unsigned int gru_max_gids;
#define GRU_MAX_BLADES MAX_NUMNODES
#define GRU_MAX_GRUS (GRU_MAX_BLADES * GRU_CHIPLETS_PER_BLADE)
#define GRU_DRIVER_ID_STR "SGI GRU Device Driver"
#define GRU_DRIVER_VERSION_STR "0.85"
/*
* GRU statistics.
*/
struct gru_stats_s {
atomic_long_t vdata_alloc;
atomic_long_t vdata_free;
atomic_long_t gts_alloc;
atomic_long_t gts_free;
atomic_long_t gms_alloc;
atomic_long_t gms_free;
atomic_long_t gts_double_allocate;
atomic_long_t assign_context;
atomic_long_t assign_context_failed;
atomic_long_t free_context;
atomic_long_t load_user_context;
atomic_long_t load_kernel_context;
atomic_long_t lock_kernel_context;
atomic_long_t unlock_kernel_context;
atomic_long_t steal_user_context;
atomic_long_t steal_kernel_context;
atomic_long_t steal_context_failed;
atomic_long_t nopfn;
atomic_long_t asid_new;
atomic_long_t asid_next;
atomic_long_t asid_wrap;
atomic_long_t asid_reuse;
atomic_long_t intr;
atomic_long_t intr_cbr;
atomic_long_t intr_tfh;
atomic_long_t intr_spurious;
atomic_long_t intr_mm_lock_failed;
atomic_long_t call_os;
atomic_long_t call_os_wait_queue;
atomic_long_t user_flush_tlb;
atomic_long_t user_unload_context;
atomic_long_t user_exception;
atomic_long_t set_context_option;
atomic_long_t check_context_retarget_intr;
atomic_long_t check_context_unload;
atomic_long_t tlb_dropin;
atomic_long_t tlb_preload_page;
atomic_long_t tlb_dropin_fail_no_asid;
atomic_long_t tlb_dropin_fail_upm;
atomic_long_t tlb_dropin_fail_invalid;
atomic_long_t tlb_dropin_fail_range_active;
atomic_long_t tlb_dropin_fail_idle;
atomic_long_t tlb_dropin_fail_fmm;
atomic_long_t tlb_dropin_fail_no_exception;
atomic_long_t tfh_stale_on_fault;
atomic_long_t mmu_invalidate_range;
atomic_long_t mmu_invalidate_page;
atomic_long_t flush_tlb;
atomic_long_t flush_tlb_gru;
atomic_long_t flush_tlb_gru_tgh;
atomic_long_t flush_tlb_gru_zero_asid;
atomic_long_t copy_gpa;
atomic_long_t read_gpa;
atomic_long_t mesq_receive;
atomic_long_t mesq_receive_none;
atomic_long_t mesq_send;
atomic_long_t mesq_send_failed;
atomic_long_t mesq_noop;
atomic_long_t mesq_send_unexpected_error;
atomic_long_t mesq_send_lb_overflow;
atomic_long_t mesq_send_qlimit_reached;
atomic_long_t mesq_send_amo_nacked;
atomic_long_t mesq_send_put_nacked;
atomic_long_t mesq_page_overflow;
atomic_long_t mesq_qf_locked;
atomic_long_t mesq_qf_noop_not_full;
atomic_long_t mesq_qf_switch_head_failed;
atomic_long_t mesq_qf_unexpected_error;
atomic_long_t mesq_noop_unexpected_error;
atomic_long_t mesq_noop_lb_overflow;
atomic_long_t mesq_noop_qlimit_reached;
atomic_long_t mesq_noop_amo_nacked;
atomic_long_t mesq_noop_put_nacked;
atomic_long_t mesq_noop_page_overflow;
};
enum mcs_op {cchop_allocate, cchop_start, cchop_interrupt, cchop_interrupt_sync,
cchop_deallocate, tfhop_write_only, tfhop_write_restart,
tghop_invalidate, mcsop_last};
struct mcs_op_statistic {
atomic_long_t count;
atomic_long_t total;
unsigned long max;
};
extern struct mcs_op_statistic mcs_op_statistics[mcsop_last];
#define OPT_DPRINT 1
#define OPT_STATS 2
#define IRQ_GRU 110 /* Starting IRQ number for interrupts */
/* Delay in jiffies between attempts to assign a GRU context */
#define GRU_ASSIGN_DELAY ((HZ * 20) / 1000)
/*
* If a process has it's context stolen, min delay in jiffies before trying to
* steal a context from another process.
*/
#define GRU_STEAL_DELAY ((HZ * 200) / 1000)
#define STAT(id) do { \
if (gru_options & OPT_STATS) \
atomic_long_inc(&gru_stats.id); \
} while (0)
#ifdef CONFIG_SGI_GRU_DEBUG
#define gru_dbg(dev, fmt, x...) \
do { \
if (gru_options & OPT_DPRINT) \
printk(KERN_DEBUG "GRU:%d %s: " fmt, smp_processor_id(), __func__, x);\
} while (0)
#else
#define gru_dbg(x...)
#endif
/*-----------------------------------------------------------------------------
* ASID management
*/
#define MAX_ASID 0xfffff0
#define MIN_ASID 8
#define ASID_INC 8 /* number of regions */
/* Generate a GRU asid value from a GRU base asid & a virtual address. */
#define VADDR_HI_BIT 64
#define GRUREGION(addr) ((addr) >> (VADDR_HI_BIT - 3) & 3)
#define GRUASID(asid, addr) ((asid) + GRUREGION(addr))
/*------------------------------------------------------------------------------
* File & VMS Tables
*/
struct gru_state;
/*
* This structure is pointed to from the mmstruct via the notifier pointer.
* There is one of these per address space.
*/
struct gru_mm_tracker { /* pack to reduce size */
unsigned int mt_asid_gen:24; /* ASID wrap count */
unsigned int mt_asid:24; /* current base ASID for gru */
unsigned short mt_ctxbitmap:16;/* bitmap of contexts using
asid */
} __attribute__ ((packed));
struct gru_mm_struct {
struct mmu_notifier ms_notifier;
atomic_t ms_refcnt;
spinlock_t ms_asid_lock; /* protects ASID assignment */
atomic_t ms_range_active;/* num range_invals active */
char ms_released;
wait_queue_head_t ms_wait_queue;
DECLARE_BITMAP(ms_asidmap, GRU_MAX_GRUS);
struct gru_mm_tracker ms_asids[GRU_MAX_GRUS];
};
/*
* One of these structures is allocated when a GSEG is mmaped. The
* structure is pointed to by the vma->vm_private_data field in the vma struct.
*/
struct gru_vma_data {
spinlock_t vd_lock; /* Serialize access to vma */
struct list_head vd_head; /* head of linked list of gts */
long vd_user_options;/* misc user option flags */
int vd_cbr_au_count;
int vd_dsr_au_count;
unsigned char vd_tlb_preload_count;
};
/*
* One of these is allocated for each thread accessing a mmaped GRU. A linked
* list of these structure is hung off the struct gru_vma_data in the mm_struct.
*/
struct gru_thread_state {
struct list_head ts_next; /* list - head at vma-private */
struct mutex ts_ctxlock; /* load/unload CTX lock */
struct mm_struct *ts_mm; /* mm currently mapped to
context */
struct vm_area_struct *ts_vma; /* vma of GRU context */
struct gru_state *ts_gru; /* GRU where the context is
loaded */
struct gru_mm_struct *ts_gms; /* asid & ioproc struct */
unsigned char ts_tlb_preload_count; /* TLB preload pages */
unsigned long ts_cbr_map; /* map of allocated CBRs */
unsigned long ts_dsr_map; /* map of allocated DATA
resources */
unsigned long ts_steal_jiffies;/* jiffies when context last
stolen */
long ts_user_options;/* misc user option flags */
pid_t ts_tgid_owner; /* task that is using the
context - for migration */
short ts_user_blade_id;/* user selected blade */
char ts_user_chiplet_id;/* user selected chiplet */
unsigned short ts_sizeavail; /* Pagesizes in use */
int ts_tsid; /* thread that owns the
structure */
int ts_tlb_int_select;/* target cpu if interrupts
enabled */
int ts_ctxnum; /* context number where the
context is loaded */
atomic_t ts_refcnt; /* reference count GTS */
unsigned char ts_dsr_au_count;/* Number of DSR resources
required for contest */
unsigned char ts_cbr_au_count;/* Number of CBR resources
required for contest */
char ts_cch_req_slice;/* CCH packet slice */
char ts_blade; /* If >= 0, migrate context if
ref from diferent blade */
char ts_force_cch_reload;
char ts_cbr_idx[GRU_CBR_AU];/* CBR numbers of each
allocated CB */
int ts_data_valid; /* Indicates if ts_gdata has
valid data */
struct gru_gseg_statistics ustats; /* User statistics */
unsigned long ts_gdata[0]; /* save area for GRU data (CB,
DS, CBE) */
};
/*
* Threaded programs actually allocate an array of GSEGs when a context is
* created. Each thread uses a separate GSEG. TSID is the index into the GSEG
* array.
*/
#define TSID(a, v) (((a) - (v)->vm_start) / GRU_GSEG_PAGESIZE)
#define UGRUADDR(gts) ((gts)->ts_vma->vm_start + \
(gts)->ts_tsid * GRU_GSEG_PAGESIZE)
#define NULLCTX (-1) /* if context not loaded into GRU */
/*-----------------------------------------------------------------------------
* GRU State Tables
*/
/*
* One of these exists for each GRU chiplet.
*/
struct gru_state {
struct gru_blade_state *gs_blade; /* GRU state for entire
blade */
unsigned long gs_gru_base_paddr; /* Physical address of
gru segments (64) */
void *gs_gru_base_vaddr; /* Virtual address of
gru segments (64) */
unsigned short gs_gid; /* unique GRU number */
unsigned short gs_blade_id; /* blade of GRU */
unsigned char gs_chiplet_id; /* blade chiplet of GRU */
unsigned char gs_tgh_local_shift; /* used to pick TGH for
local flush */
unsigned char gs_tgh_first_remote; /* starting TGH# for
remote flush */
spinlock_t gs_asid_lock; /* lock used for
assigning asids */
spinlock_t gs_lock; /* lock used for
assigning contexts */
/* -- the following are protected by the gs_asid_lock spinlock ---- */
unsigned int gs_asid; /* Next availe ASID */
unsigned int gs_asid_limit; /* Limit of available
ASIDs */
unsigned int gs_asid_gen; /* asid generation.
Inc on wrap */
/* --- the following fields are protected by the gs_lock spinlock --- */
unsigned long gs_context_map; /* bitmap to manage
contexts in use */
unsigned long gs_cbr_map; /* bitmap to manage CB
resources */
unsigned long gs_dsr_map; /* bitmap used to manage
DATA resources */
unsigned int gs_reserved_cbrs; /* Number of kernel-
reserved cbrs */
unsigned int gs_reserved_dsr_bytes; /* Bytes of kernel-
reserved dsrs */
unsigned short gs_active_contexts; /* number of contexts
in use */
struct gru_thread_state *gs_gts[GRU_NUM_CCH]; /* GTS currently using
the context */
int gs_irq[GRU_NUM_TFM]; /* Interrupt irqs */
};
/*
* This structure contains the GRU state for all the GRUs on a blade.
*/
struct gru_blade_state {
void *kernel_cb; /* First kernel
reserved cb */
void *kernel_dsr; /* First kernel
reserved DSR */
struct rw_semaphore bs_kgts_sema; /* lock for kgts */
struct gru_thread_state *bs_kgts; /* GTS for kernel use */
/* ---- the following are used for managing kernel async GRU CBRs --- */
int bs_async_dsr_bytes; /* DSRs for async */
int bs_async_cbrs; /* CBRs AU for async */
struct completion *bs_async_wq;
/* ---- the following are protected by the bs_lock spinlock ---- */
spinlock_t bs_lock; /* lock used for
stealing contexts */
int bs_lru_ctxnum; /* STEAL - last context
stolen */
struct gru_state *bs_lru_gru; /* STEAL - last gru
stolen */
struct gru_state bs_grus[GRU_CHIPLETS_PER_BLADE];
};
/*-----------------------------------------------------------------------------
* Address Primitives
*/
#define get_tfm_for_cpu(g, c) \
((struct gru_tlb_fault_map *)get_tfm((g)->gs_gru_base_vaddr, (c)))
#define get_tfh_by_index(g, i) \
((struct gru_tlb_fault_handle *)get_tfh((g)->gs_gru_base_vaddr, (i)))
#define get_tgh_by_index(g, i) \
((struct gru_tlb_global_handle *)get_tgh((g)->gs_gru_base_vaddr, (i)))
#define get_cbe_by_index(g, i) \
((struct gru_control_block_extended *)get_cbe((g)->gs_gru_base_vaddr,\
(i)))
/*-----------------------------------------------------------------------------
* Useful Macros
*/
/* Given a blade# & chiplet#, get a pointer to the GRU */
#define get_gru(b, c) (&gru_base[b]->bs_grus[c])
/* Number of bytes to save/restore when unloading/loading GRU contexts */
#define DSR_BYTES(dsr) ((dsr) * GRU_DSR_AU_BYTES)
#define CBR_BYTES(cbr) ((cbr) * GRU_HANDLE_BYTES * GRU_CBR_AU_SIZE * 2)
/* Convert a user CB number to the actual CBRNUM */
#define thread_cbr_number(gts, n) ((gts)->ts_cbr_idx[(n) / GRU_CBR_AU_SIZE] \
* GRU_CBR_AU_SIZE + (n) % GRU_CBR_AU_SIZE)
/* Convert a gid to a pointer to the GRU */
#define GID_TO_GRU(gid) \
(gru_base[(gid) / GRU_CHIPLETS_PER_BLADE] ? \
(&gru_base[(gid) / GRU_CHIPLETS_PER_BLADE]-> \
bs_grus[(gid) % GRU_CHIPLETS_PER_BLADE]) : \
NULL)
/* Scan all active GRUs in a GRU bitmap */
#define for_each_gru_in_bitmap(gid, map) \
for_each_set_bit((gid), (map), GRU_MAX_GRUS)
/* Scan all active GRUs on a specific blade */
#define for_each_gru_on_blade(gru, nid, i) \
for ((gru) = gru_base[nid]->bs_grus, (i) = 0; \
(i) < GRU_CHIPLETS_PER_BLADE; \
(i)++, (gru)++)
/* Scan all GRUs */
#define foreach_gid(gid) \
for ((gid) = 0; (gid) < gru_max_gids; (gid)++)
/* Scan all active GTSs on a gru. Note: must hold ss_lock to use this macro. */
#define for_each_gts_on_gru(gts, gru, ctxnum) \
for ((ctxnum) = 0; (ctxnum) < GRU_NUM_CCH; (ctxnum)++) \
if (((gts) = (gru)->gs_gts[ctxnum]))
/* Scan each CBR whose bit is set in a TFM (or copy of) */
#define for_each_cbr_in_tfm(i, map) \
for_each_set_bit((i), (map), GRU_NUM_CBE)
/* Scan each CBR in a CBR bitmap. Note: multiple CBRs in an allocation unit */
#define for_each_cbr_in_allocation_map(i, map, k) \
for_each_set_bit((k), (map), GRU_CBR_AU) \
for ((i) = (k)*GRU_CBR_AU_SIZE; \
(i) < ((k) + 1) * GRU_CBR_AU_SIZE; (i)++)
/* Scan each DSR in a DSR bitmap. Note: multiple DSRs in an allocation unit */
#define for_each_dsr_in_allocation_map(i, map, k) \
for_each_set_bit((k), (const unsigned long *)(map), GRU_DSR_AU) \
for ((i) = (k) * GRU_DSR_AU_CL; \
(i) < ((k) + 1) * GRU_DSR_AU_CL; (i)++)
#define gseg_physical_address(gru, ctxnum) \
((gru)->gs_gru_base_paddr + ctxnum * GRU_GSEG_STRIDE)
#define gseg_virtual_address(gru, ctxnum) \
((gru)->gs_gru_base_vaddr + ctxnum * GRU_GSEG_STRIDE)
/*-----------------------------------------------------------------------------
* Lock / Unlock GRU handles
* Use the "delresp" bit in the handle as a "lock" bit.
*/
/* Lock hierarchy checking enabled only in emulator */
/* 0 = lock failed, 1 = locked */
static inline int __trylock_handle(void *h)
{
return !test_and_set_bit(1, h);
}
static inline void __lock_handle(void *h)
{
while (test_and_set_bit(1, h))
cpu_relax();
}
static inline void __unlock_handle(void *h)
{
clear_bit(1, h);
}
static inline int trylock_cch_handle(struct gru_context_configuration_handle *cch)
{
return __trylock_handle(cch);
}
static inline void lock_cch_handle(struct gru_context_configuration_handle *cch)
{
__lock_handle(cch);
}
static inline void unlock_cch_handle(struct gru_context_configuration_handle
*cch)
{
__unlock_handle(cch);
}
static inline void lock_tgh_handle(struct gru_tlb_global_handle *tgh)
{
__lock_handle(tgh);
}
static inline void unlock_tgh_handle(struct gru_tlb_global_handle *tgh)
{
__unlock_handle(tgh);
}
static inline int is_kernel_context(struct gru_thread_state *gts)
{
return !gts->ts_mm;
}
/*
* The following are for Nehelem-EX. A more general scheme is needed for
* future processors.
*/
#define UV_MAX_INT_CORES 8
#define uv_cpu_socket_number(p) ((cpu_physical_id(p) >> 5) & 1)
#define uv_cpu_ht_number(p) (cpu_physical_id(p) & 1)
#define uv_cpu_core_number(p) (((cpu_physical_id(p) >> 2) & 4) | \
((cpu_physical_id(p) >> 1) & 3))
/*-----------------------------------------------------------------------------
* Function prototypes & externs
*/
struct gru_unload_context_req;
extern const struct vm_operations_struct gru_vm_ops;
extern struct device *grudev;
extern struct gru_vma_data *gru_alloc_vma_data(struct vm_area_struct *vma,
int tsid);
extern struct gru_thread_state *gru_find_thread_state(struct vm_area_struct
*vma, int tsid);
extern struct gru_thread_state *gru_alloc_thread_state(struct vm_area_struct
*vma, int tsid);
extern struct gru_state *gru_assign_gru_context(struct gru_thread_state *gts);
extern void gru_load_context(struct gru_thread_state *gts);
extern void gru_steal_context(struct gru_thread_state *gts);
extern void gru_unload_context(struct gru_thread_state *gts, int savestate);
extern int gru_update_cch(struct gru_thread_state *gts);
extern void gts_drop(struct gru_thread_state *gts);
extern void gru_tgh_flush_init(struct gru_state *gru);
extern int gru_kservices_init(void);
extern void gru_kservices_exit(void);
extern irqreturn_t gru0_intr(int irq, void *dev_id);
extern irqreturn_t gru1_intr(int irq, void *dev_id);
extern irqreturn_t gru_intr_mblade(int irq, void *dev_id);
extern int gru_dump_chiplet_request(unsigned long arg);
extern long gru_get_gseg_statistics(unsigned long arg);
extern int gru_handle_user_call_os(unsigned long address);
extern int gru_user_flush_tlb(unsigned long arg);
extern int gru_user_unload_context(unsigned long arg);
extern int gru_get_exception_detail(unsigned long arg);
extern int gru_set_context_option(unsigned long address);
extern void gru_check_context_placement(struct gru_thread_state *gts);
extern int gru_cpu_fault_map_id(void);
extern struct vm_area_struct *gru_find_vma(unsigned long vaddr);
extern void gru_flush_all_tlb(struct gru_state *gru);
extern int gru_proc_init(void);
extern void gru_proc_exit(void);
extern struct gru_thread_state *gru_alloc_gts(struct vm_area_struct *vma,
int cbr_au_count, int dsr_au_count,
unsigned char tlb_preload_count, int options, int tsid);
extern unsigned long gru_reserve_cb_resources(struct gru_state *gru,
int cbr_au_count, char *cbmap);
extern unsigned long gru_reserve_ds_resources(struct gru_state *gru,
int dsr_au_count, char *dsmap);
extern int gru_fault(struct vm_area_struct *, struct vm_fault *vmf);
extern struct gru_mm_struct *gru_register_mmu_notifier(void);
extern void gru_drop_mmu_notifier(struct gru_mm_struct *gms);
extern int gru_ktest(unsigned long arg);
extern void gru_flush_tlb_range(struct gru_mm_struct *gms, unsigned long start,
unsigned long len);
extern unsigned long gru_options;
#endif /* __GRUTABLES_H__ */
