blob: c4acac74725c4de50ef0954a258a851c05a03930 [file] [log] [blame]
Jack Steiner14258642008-07-29 22:33:57 -07001/*
2 * SN Platform GRU Driver
3 *
4 * FAULT HANDLER FOR GRU DETECTED TLB MISSES
5 *
6 * This file contains code that handles TLB misses within the GRU.
7 * These misses are reported either via interrupts or user polling of
8 * the user CB.
9 *
10 * Copyright (c) 2008 Silicon Graphics, Inc. All Rights Reserved.
11 *
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License as published by
14 * the Free Software Foundation; either version 2 of the License, or
15 * (at your option) any later version.
16 *
17 * This program is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 * GNU General Public License for more details.
21 *
22 * You should have received a copy of the GNU General Public License
23 * along with this program; if not, write to the Free Software
24 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
25 */
26
27#include <linux/kernel.h>
28#include <linux/errno.h>
29#include <linux/spinlock.h>
30#include <linux/mm.h>
31#include <linux/hugetlb.h>
32#include <linux/device.h>
33#include <linux/io.h>
34#include <linux/uaccess.h>
Jack Steinerbb04aa72009-04-02 16:59:07 -070035#include <linux/security.h>
Linus Torvalds268bb0c2011-05-20 12:50:29 -070036#include <linux/prefetch.h>
Jack Steiner14258642008-07-29 22:33:57 -070037#include <asm/pgtable.h>
38#include "gru.h"
39#include "grutables.h"
40#include "grulib.h"
41#include "gru_instructions.h"
42#include <asm/uv/uv_hub.h>
43
Jack Steiner9c13cb32009-12-15 16:48:14 -080044/* Return codes for vtop functions */
45#define VTOP_SUCCESS 0
46#define VTOP_INVALID -1
47#define VTOP_RETRY -2
48
49
Jack Steiner14258642008-07-29 22:33:57 -070050/*
51 * Test if a physical address is a valid GRU GSEG address
52 */
53static inline int is_gru_paddr(unsigned long paddr)
54{
55 return paddr >= gru_start_paddr && paddr < gru_end_paddr;
56}
57
58/*
59 * Find the vma of a GRU segment. Caller must hold mmap_sem.
60 */
61struct vm_area_struct *gru_find_vma(unsigned long vaddr)
62{
63 struct vm_area_struct *vma;
64
65 vma = find_vma(current->mm, vaddr);
66 if (vma && vma->vm_start <= vaddr && vma->vm_ops == &gru_vm_ops)
67 return vma;
68 return NULL;
69}
70
71/*
72 * Find and lock the gts that contains the specified user vaddr.
73 *
74 * Returns:
75 * - *gts with the mmap_sem locked for read and the GTS locked.
76 * - NULL if vaddr invalid OR is not a valid GSEG vaddr.
77 */
78
79static struct gru_thread_state *gru_find_lock_gts(unsigned long vaddr)
80{
81 struct mm_struct *mm = current->mm;
82 struct vm_area_struct *vma;
83 struct gru_thread_state *gts = NULL;
84
85 down_read(&mm->mmap_sem);
86 vma = gru_find_vma(vaddr);
87 if (vma)
88 gts = gru_find_thread_state(vma, TSID(vaddr, vma));
89 if (gts)
90 mutex_lock(&gts->ts_ctxlock);
91 else
92 up_read(&mm->mmap_sem);
93 return gts;
94}
95
96static struct gru_thread_state *gru_alloc_locked_gts(unsigned long vaddr)
97{
98 struct mm_struct *mm = current->mm;
99 struct vm_area_struct *vma;
Jack Steinere0060432009-12-15 16:48:10 -0800100 struct gru_thread_state *gts = ERR_PTR(-EINVAL);
Jack Steiner14258642008-07-29 22:33:57 -0700101
102 down_write(&mm->mmap_sem);
103 vma = gru_find_vma(vaddr);
Jack Steinere0060432009-12-15 16:48:10 -0800104 if (!vma)
105 goto err;
Jack Steiner14258642008-07-29 22:33:57 -0700106
Jack Steinere0060432009-12-15 16:48:10 -0800107 gts = gru_alloc_thread_state(vma, TSID(vaddr, vma));
108 if (IS_ERR(gts))
109 goto err;
110 mutex_lock(&gts->ts_ctxlock);
111 downgrade_write(&mm->mmap_sem);
112 return gts;
113
114err:
115 up_write(&mm->mmap_sem);
Jack Steiner14258642008-07-29 22:33:57 -0700116 return gts;
117}
118
119/*
120 * Unlock a GTS that was previously locked with gru_find_lock_gts().
121 */
122static void gru_unlock_gts(struct gru_thread_state *gts)
123{
124 mutex_unlock(&gts->ts_ctxlock);
125 up_read(&current->mm->mmap_sem);
126}
127
128/*
129 * Set a CB.istatus to active using a user virtual address. This must be done
130 * just prior to a TFH RESTART. The new cb.istatus is an in-cache status ONLY.
131 * If the line is evicted, the status may be lost. The in-cache update
132 * is necessary to prevent the user from seeing a stale cb.istatus that will
133 * change as soon as the TFH restart is complete. Races may cause an
134 * occasional failure to clear the cb.istatus, but that is ok.
Jack Steiner14258642008-07-29 22:33:57 -0700135 */
Jack Steinerb61fc692009-12-15 16:48:03 -0800136static void gru_cb_set_istatus_active(struct gru_instruction_bits *cbk)
Jack Steiner14258642008-07-29 22:33:57 -0700137{
Jack Steinerb61fc692009-12-15 16:48:03 -0800138 if (cbk) {
139 cbk->istatus = CBS_ACTIVE;
Jack Steiner14258642008-07-29 22:33:57 -0700140 }
141}
142
143/*
Jack Steiner14258642008-07-29 22:33:57 -0700144 * Read & clear a TFM
145 *
146 * The GRU has an array of fault maps. A map is private to a cpu
147 * Only one cpu will be accessing a cpu's fault map.
148 *
149 * This function scans the cpu-private fault map & clears all bits that
150 * are set. The function returns a bitmap that indicates the bits that
151 * were cleared. Note that sense the maps may be updated asynchronously by
152 * the GRU, atomic operations must be used to clear bits.
153 */
154static void get_clear_fault_map(struct gru_state *gru,
Jack Steiner4a7a17c2009-06-17 16:28:25 -0700155 struct gru_tlb_fault_map *imap,
156 struct gru_tlb_fault_map *dmap)
Jack Steiner14258642008-07-29 22:33:57 -0700157{
158 unsigned long i, k;
159 struct gru_tlb_fault_map *tfm;
160
161 tfm = get_tfm_for_cpu(gru, gru_cpu_fault_map_id());
162 prefetchw(tfm); /* Helps on hardware, required for emulator */
163 for (i = 0; i < BITS_TO_LONGS(GRU_NUM_CBE); i++) {
164 k = tfm->fault_bits[i];
165 if (k)
166 k = xchg(&tfm->fault_bits[i], 0UL);
Jack Steiner4a7a17c2009-06-17 16:28:25 -0700167 imap->fault_bits[i] = k;
168 k = tfm->done_bits[i];
169 if (k)
170 k = xchg(&tfm->done_bits[i], 0UL);
171 dmap->fault_bits[i] = k;
Jack Steiner14258642008-07-29 22:33:57 -0700172 }
173
174 /*
175 * Not functionally required but helps performance. (Required
176 * on emulator)
177 */
178 gru_flush_cache(tfm);
179}
180
181/*
182 * Atomic (interrupt context) & non-atomic (user context) functions to
183 * convert a vaddr into a physical address. The size of the page
184 * is returned in pageshift.
185 * returns:
186 * 0 - successful
187 * < 0 - error code
188 * 1 - (atomic only) try again in non-atomic context
189 */
190static int non_atomic_pte_lookup(struct vm_area_struct *vma,
191 unsigned long vaddr, int write,
192 unsigned long *paddr, int *pageshift)
193{
194 struct page *page;
195
Jack Steiner74ccd092009-12-15 16:48:17 -0800196#ifdef CONFIG_HUGETLB_PAGE
197 *pageshift = is_vm_hugetlb_page(vma) ? HPAGE_SHIFT : PAGE_SHIFT;
198#else
Jack Steiner14258642008-07-29 22:33:57 -0700199 *pageshift = PAGE_SHIFT;
Jack Steiner74ccd092009-12-15 16:48:17 -0800200#endif
Jack Steiner14258642008-07-29 22:33:57 -0700201 if (get_user_pages
202 (current, current->mm, vaddr, 1, write, 0, &page, NULL) <= 0)
203 return -EFAULT;
204 *paddr = page_to_phys(page);
205 put_page(page);
206 return 0;
207}
208
209/*
Jack Steiner14258642008-07-29 22:33:57 -0700210 * atomic_pte_lookup
211 *
212 * Convert a user virtual address to a physical address
213 * Only supports Intel large pages (2MB only) on x86_64.
214 * ZZZ - hugepage support is incomplete
Jack Steiner923f7f62008-10-15 22:05:13 -0700215 *
216 * NOTE: mmap_sem is already held on entry to this function. This
217 * guarantees existence of the page tables.
Jack Steiner14258642008-07-29 22:33:57 -0700218 */
219static int atomic_pte_lookup(struct vm_area_struct *vma, unsigned long vaddr,
220 int write, unsigned long *paddr, int *pageshift)
221{
222 pgd_t *pgdp;
223 pmd_t *pmdp;
224 pud_t *pudp;
225 pte_t pte;
226
Jack Steiner14258642008-07-29 22:33:57 -0700227 pgdp = pgd_offset(vma->vm_mm, vaddr);
228 if (unlikely(pgd_none(*pgdp)))
229 goto err;
230
231 pudp = pud_offset(pgdp, vaddr);
232 if (unlikely(pud_none(*pudp)))
233 goto err;
234
235 pmdp = pmd_offset(pudp, vaddr);
236 if (unlikely(pmd_none(*pmdp)))
237 goto err;
238#ifdef CONFIG_X86_64
239 if (unlikely(pmd_large(*pmdp)))
240 pte = *(pte_t *) pmdp;
241 else
242#endif
243 pte = *pte_offset_kernel(pmdp, vaddr);
244
Jack Steiner14258642008-07-29 22:33:57 -0700245 if (unlikely(!pte_present(pte) ||
246 (write && (!pte_write(pte) || !pte_dirty(pte)))))
247 return 1;
248
249 *paddr = pte_pfn(pte) << PAGE_SHIFT;
Jack Steiner023a4072008-12-09 10:51:32 -0600250#ifdef CONFIG_HUGETLB_PAGE
Jack Steiner14258642008-07-29 22:33:57 -0700251 *pageshift = is_vm_hugetlb_page(vma) ? HPAGE_SHIFT : PAGE_SHIFT;
Jack Steiner023a4072008-12-09 10:51:32 -0600252#else
253 *pageshift = PAGE_SHIFT;
254#endif
Jack Steiner14258642008-07-29 22:33:57 -0700255 return 0;
256
257err:
Jack Steiner14258642008-07-29 22:33:57 -0700258 return 1;
259}
260
Jack Steinerecdaf2b2009-04-02 16:59:09 -0700261static int gru_vtop(struct gru_thread_state *gts, unsigned long vaddr,
262 int write, int atomic, unsigned long *gpa, int *pageshift)
263{
264 struct mm_struct *mm = gts->ts_mm;
265 struct vm_area_struct *vma;
266 unsigned long paddr;
267 int ret, ps;
268
269 vma = find_vma(mm, vaddr);
270 if (!vma)
271 goto inval;
272
273 /*
274 * Atomic lookup is faster & usually works even if called in non-atomic
275 * context.
276 */
277 rmb(); /* Must/check ms_range_active before loading PTEs */
278 ret = atomic_pte_lookup(vma, vaddr, write, &paddr, &ps);
279 if (ret) {
280 if (atomic)
281 goto upm;
282 if (non_atomic_pte_lookup(vma, vaddr, write, &paddr, &ps))
283 goto inval;
284 }
285 if (is_gru_paddr(paddr))
286 goto inval;
287 paddr = paddr & ~((1UL << ps) - 1);
288 *gpa = uv_soc_phys_ram_to_gpa(paddr);
289 *pageshift = ps;
Jack Steiner9c13cb32009-12-15 16:48:14 -0800290 return VTOP_SUCCESS;
Jack Steinerecdaf2b2009-04-02 16:59:09 -0700291
292inval:
Jack Steiner9c13cb32009-12-15 16:48:14 -0800293 return VTOP_INVALID;
Jack Steinerecdaf2b2009-04-02 16:59:09 -0700294upm:
Jack Steiner9c13cb32009-12-15 16:48:14 -0800295 return VTOP_RETRY;
Jack Steinerecdaf2b2009-04-02 16:59:09 -0700296}
297
298
Jack Steiner14258642008-07-29 22:33:57 -0700299/*
Jack Steinerc5502222009-12-15 16:48:13 -0800300 * Flush a CBE from cache. The CBE is clean in the cache. Dirty the
301 * CBE cacheline so that the line will be written back to home agent.
302 * Otherwise the line may be silently dropped. This has no impact
303 * except on performance.
304 */
305static void gru_flush_cache_cbe(struct gru_control_block_extended *cbe)
306{
307 if (unlikely(cbe)) {
308 cbe->cbrexecstatus = 0; /* make CL dirty */
309 gru_flush_cache(cbe);
310 }
311}
312
313/*
314 * Preload the TLB with entries that may be required. Currently, preloading
315 * is implemented only for BCOPY. Preload <tlb_preload_count> pages OR to
316 * the end of the bcopy tranfer, whichever is smaller.
317 */
318static void gru_preload_tlb(struct gru_state *gru,
319 struct gru_thread_state *gts, int atomic,
320 unsigned long fault_vaddr, int asid, int write,
321 unsigned char tlb_preload_count,
322 struct gru_tlb_fault_handle *tfh,
323 struct gru_control_block_extended *cbe)
324{
325 unsigned long vaddr = 0, gpa;
326 int ret, pageshift;
327
328 if (cbe->opccpy != OP_BCOPY)
329 return;
330
331 if (fault_vaddr == cbe->cbe_baddr0)
332 vaddr = fault_vaddr + GRU_CACHE_LINE_BYTES * cbe->cbe_src_cl - 1;
333 else if (fault_vaddr == cbe->cbe_baddr1)
334 vaddr = fault_vaddr + (1 << cbe->xtypecpy) * cbe->cbe_nelemcur - 1;
335
336 fault_vaddr &= PAGE_MASK;
337 vaddr &= PAGE_MASK;
338 vaddr = min(vaddr, fault_vaddr + tlb_preload_count * PAGE_SIZE);
339
340 while (vaddr > fault_vaddr) {
341 ret = gru_vtop(gts, vaddr, write, atomic, &gpa, &pageshift);
342 if (ret || tfh_write_only(tfh, gpa, GAA_RAM, vaddr, asid, write,
343 GRU_PAGESIZE(pageshift)))
344 return;
345 gru_dbg(grudev,
346 "%s: gid %d, gts 0x%p, tfh 0x%p, vaddr 0x%lx, asid 0x%x, rw %d, ps %d, gpa 0x%lx\n",
347 atomic ? "atomic" : "non-atomic", gru->gs_gid, gts, tfh,
348 vaddr, asid, write, pageshift, gpa);
349 vaddr -= PAGE_SIZE;
350 STAT(tlb_preload_page);
351 }
352}
353
354/*
Jack Steiner14258642008-07-29 22:33:57 -0700355 * Drop a TLB entry into the GRU. The fault is described by info in an TFH.
356 * Input:
357 * cb Address of user CBR. Null if not running in user context
358 * Return:
359 * 0 = dropin, exception, or switch to UPM successful
360 * 1 = range invalidate active
361 * < 0 = error code
362 *
363 */
Jack Steiner2ce4d4c2009-12-15 16:48:18 -0800364static int gru_try_dropin(struct gru_state *gru,
365 struct gru_thread_state *gts,
Jack Steiner14258642008-07-29 22:33:57 -0700366 struct gru_tlb_fault_handle *tfh,
Jack Steinerb61fc692009-12-15 16:48:03 -0800367 struct gru_instruction_bits *cbk)
Jack Steiner14258642008-07-29 22:33:57 -0700368{
Jack Steinerc5502222009-12-15 16:48:13 -0800369 struct gru_control_block_extended *cbe = NULL;
370 unsigned char tlb_preload_count = gts->ts_tlb_preload_count;
Jack Steiner563447d2009-12-15 16:48:12 -0800371 int pageshift = 0, asid, write, ret, atomic = !cbk, indexway;
Jack Steinerecdaf2b2009-04-02 16:59:09 -0700372 unsigned long gpa = 0, vaddr = 0;
Jack Steiner14258642008-07-29 22:33:57 -0700373
374 /*
375 * NOTE: The GRU contains magic hardware that eliminates races between
376 * TLB invalidates and TLB dropins. If an invalidate occurs
377 * in the window between reading the TFH and the subsequent TLB dropin,
378 * the dropin is ignored. This eliminates the need for additional locks.
379 */
380
381 /*
Jack Steinerc5502222009-12-15 16:48:13 -0800382 * Prefetch the CBE if doing TLB preloading
383 */
384 if (unlikely(tlb_preload_count)) {
385 cbe = gru_tfh_to_cbe(tfh);
386 prefetchw(cbe);
387 }
388
389 /*
Jack Steiner14258642008-07-29 22:33:57 -0700390 * Error if TFH state is IDLE or FMM mode & the user issuing a UPM call.
391 * Might be a hardware race OR a stupid user. Ignore FMM because FMM
392 * is a transient state.
393 */
Jack Steiner270952a2009-06-17 16:28:27 -0700394 if (tfh->status != TFHSTATUS_EXCEPTION) {
395 gru_flush_cache(tfh);
Jack Steiner67bf04a2009-12-15 16:48:11 -0800396 sync_core();
Jack Steiner270952a2009-06-17 16:28:27 -0700397 if (tfh->status != TFHSTATUS_EXCEPTION)
398 goto failnoexception;
399 STAT(tfh_stale_on_fault);
400 }
Jack Steiner14258642008-07-29 22:33:57 -0700401 if (tfh->state == TFHSTATE_IDLE)
402 goto failidle;
Jack Steinerb61fc692009-12-15 16:48:03 -0800403 if (tfh->state == TFHSTATE_MISS_FMM && cbk)
Jack Steiner14258642008-07-29 22:33:57 -0700404 goto failfmm;
405
406 write = (tfh->cause & TFHCAUSE_TLB_MOD) != 0;
407 vaddr = tfh->missvaddr;
408 asid = tfh->missasid;
Jack Steiner563447d2009-12-15 16:48:12 -0800409 indexway = tfh->indexway;
Jack Steiner14258642008-07-29 22:33:57 -0700410 if (asid == 0)
411 goto failnoasid;
412
413 rmb(); /* TFH must be cache resident before reading ms_range_active */
414
415 /*
416 * TFH is cache resident - at least briefly. Fail the dropin
417 * if a range invalidate is active.
418 */
419 if (atomic_read(&gts->ts_gms->ms_range_active))
420 goto failactive;
421
Jack Steinerecdaf2b2009-04-02 16:59:09 -0700422 ret = gru_vtop(gts, vaddr, write, atomic, &gpa, &pageshift);
Jack Steiner9c13cb32009-12-15 16:48:14 -0800423 if (ret == VTOP_INVALID)
Jack Steiner14258642008-07-29 22:33:57 -0700424 goto failinval;
Jack Steiner9c13cb32009-12-15 16:48:14 -0800425 if (ret == VTOP_RETRY)
Jack Steinerecdaf2b2009-04-02 16:59:09 -0700426 goto failupm;
Jack Steiner14258642008-07-29 22:33:57 -0700427
Jack Steiner7b8274e2009-04-02 16:59:12 -0700428 if (!(gts->ts_sizeavail & GRU_SIZEAVAIL(pageshift))) {
429 gts->ts_sizeavail |= GRU_SIZEAVAIL(pageshift);
Jack Steiner99f7c222009-12-15 16:48:06 -0800430 if (atomic || !gru_update_cch(gts)) {
Jack Steiner7b8274e2009-04-02 16:59:12 -0700431 gts->ts_force_cch_reload = 1;
432 goto failupm;
433 }
434 }
Jack Steinerc5502222009-12-15 16:48:13 -0800435
436 if (unlikely(cbe) && pageshift == PAGE_SHIFT) {
Jack Steiner2ce4d4c2009-12-15 16:48:18 -0800437 gru_preload_tlb(gru, gts, atomic, vaddr, asid, write, tlb_preload_count, tfh, cbe);
Jack Steinerc5502222009-12-15 16:48:13 -0800438 gru_flush_cache_cbe(cbe);
439 }
440
Jack Steinerb61fc692009-12-15 16:48:03 -0800441 gru_cb_set_istatus_active(cbk);
Jack Steiner5958ab82009-12-15 16:48:18 -0800442 gts->ustats.tlbdropin++;
Jack Steiner14258642008-07-29 22:33:57 -0700443 tfh_write_restart(tfh, gpa, GAA_RAM, vaddr, asid, write,
444 GRU_PAGESIZE(pageshift));
Jack Steiner14258642008-07-29 22:33:57 -0700445 gru_dbg(grudev,
Jack Steiner563447d2009-12-15 16:48:12 -0800446 "%s: gid %d, gts 0x%p, tfh 0x%p, vaddr 0x%lx, asid 0x%x, indexway 0x%x,"
447 " rw %d, ps %d, gpa 0x%lx\n",
Jack Steiner2ce4d4c2009-12-15 16:48:18 -0800448 atomic ? "atomic" : "non-atomic", gru->gs_gid, gts, tfh, vaddr, asid,
Jack Steiner563447d2009-12-15 16:48:12 -0800449 indexway, write, pageshift, gpa);
450 STAT(tlb_dropin);
Jack Steiner14258642008-07-29 22:33:57 -0700451 return 0;
452
453failnoasid:
454 /* No asid (delayed unload). */
455 STAT(tlb_dropin_fail_no_asid);
456 gru_dbg(grudev, "FAILED no_asid tfh: 0x%p, vaddr 0x%lx\n", tfh, vaddr);
Jack Steinerb61fc692009-12-15 16:48:03 -0800457 if (!cbk)
Jack Steiner14258642008-07-29 22:33:57 -0700458 tfh_user_polling_mode(tfh);
459 else
460 gru_flush_cache(tfh);
Jack Steinerc5502222009-12-15 16:48:13 -0800461 gru_flush_cache_cbe(cbe);
Jack Steiner14258642008-07-29 22:33:57 -0700462 return -EAGAIN;
463
464failupm:
465 /* Atomic failure switch CBR to UPM */
466 tfh_user_polling_mode(tfh);
Jack Steinerc5502222009-12-15 16:48:13 -0800467 gru_flush_cache_cbe(cbe);
Jack Steiner14258642008-07-29 22:33:57 -0700468 STAT(tlb_dropin_fail_upm);
469 gru_dbg(grudev, "FAILED upm tfh: 0x%p, vaddr 0x%lx\n", tfh, vaddr);
470 return 1;
471
472failfmm:
473 /* FMM state on UPM call */
Jack Steinerfe5bb6b2009-04-02 16:59:04 -0700474 gru_flush_cache(tfh);
Jack Steinerc5502222009-12-15 16:48:13 -0800475 gru_flush_cache_cbe(cbe);
Jack Steiner14258642008-07-29 22:33:57 -0700476 STAT(tlb_dropin_fail_fmm);
477 gru_dbg(grudev, "FAILED fmm tfh: 0x%p, state %d\n", tfh, tfh->state);
478 return 0;
479
Jack Steinercd1334f2009-06-17 16:28:19 -0700480failnoexception:
481 /* TFH status did not show exception pending */
482 gru_flush_cache(tfh);
Jack Steinerc5502222009-12-15 16:48:13 -0800483 gru_flush_cache_cbe(cbe);
Jack Steinerb61fc692009-12-15 16:48:03 -0800484 if (cbk)
485 gru_flush_cache(cbk);
Jack Steinercd1334f2009-06-17 16:28:19 -0700486 STAT(tlb_dropin_fail_no_exception);
Jack Steinerb61fc692009-12-15 16:48:03 -0800487 gru_dbg(grudev, "FAILED non-exception tfh: 0x%p, status %d, state %d\n",
488 tfh, tfh->status, tfh->state);
Jack Steinercd1334f2009-06-17 16:28:19 -0700489 return 0;
490
Jack Steiner14258642008-07-29 22:33:57 -0700491failidle:
Jack Steinercd1334f2009-06-17 16:28:19 -0700492 /* TFH state was idle - no miss pending */
Jack Steiner14258642008-07-29 22:33:57 -0700493 gru_flush_cache(tfh);
Jack Steinerc5502222009-12-15 16:48:13 -0800494 gru_flush_cache_cbe(cbe);
Jack Steinerb61fc692009-12-15 16:48:03 -0800495 if (cbk)
496 gru_flush_cache(cbk);
Jack Steiner14258642008-07-29 22:33:57 -0700497 STAT(tlb_dropin_fail_idle);
498 gru_dbg(grudev, "FAILED idle tfh: 0x%p, state %d\n", tfh, tfh->state);
499 return 0;
500
501failinval:
502 /* All errors (atomic & non-atomic) switch CBR to EXCEPTION state */
503 tfh_exception(tfh);
Jack Steinerc5502222009-12-15 16:48:13 -0800504 gru_flush_cache_cbe(cbe);
Jack Steiner14258642008-07-29 22:33:57 -0700505 STAT(tlb_dropin_fail_invalid);
506 gru_dbg(grudev, "FAILED inval tfh: 0x%p, vaddr 0x%lx\n", tfh, vaddr);
507 return -EFAULT;
508
509failactive:
510 /* Range invalidate active. Switch to UPM iff atomic */
Jack Steinerb61fc692009-12-15 16:48:03 -0800511 if (!cbk)
Jack Steiner14258642008-07-29 22:33:57 -0700512 tfh_user_polling_mode(tfh);
513 else
514 gru_flush_cache(tfh);
Jack Steinerc5502222009-12-15 16:48:13 -0800515 gru_flush_cache_cbe(cbe);
Jack Steiner14258642008-07-29 22:33:57 -0700516 STAT(tlb_dropin_fail_range_active);
517 gru_dbg(grudev, "FAILED range active: tfh 0x%p, vaddr 0x%lx\n",
518 tfh, vaddr);
519 return 1;
520}
521
522/*
523 * Process an external interrupt from the GRU. This interrupt is
524 * caused by a TLB miss.
525 * Note that this is the interrupt handler that is registered with linux
526 * interrupt handlers.
527 */
Jack Steiner4107e1d2009-12-15 16:48:11 -0800528static irqreturn_t gru_intr(int chiplet, int blade)
Jack Steiner14258642008-07-29 22:33:57 -0700529{
530 struct gru_state *gru;
Jack Steiner4a7a17c2009-06-17 16:28:25 -0700531 struct gru_tlb_fault_map imap, dmap;
Jack Steiner14258642008-07-29 22:33:57 -0700532 struct gru_thread_state *gts;
533 struct gru_tlb_fault_handle *tfh = NULL;
Jack Steiner2ce4d4c2009-12-15 16:48:18 -0800534 struct completion *cmp;
Jack Steiner14258642008-07-29 22:33:57 -0700535 int cbrnum, ctxnum;
536
537 STAT(intr);
538
Jack Steiner4107e1d2009-12-15 16:48:11 -0800539 gru = &gru_base[blade]->bs_grus[chiplet];
Jack Steiner14258642008-07-29 22:33:57 -0700540 if (!gru) {
Jack Steiner4107e1d2009-12-15 16:48:11 -0800541 dev_err(grudev, "GRU: invalid interrupt: cpu %d, chiplet %d\n",
542 raw_smp_processor_id(), chiplet);
Jack Steiner14258642008-07-29 22:33:57 -0700543 return IRQ_NONE;
544 }
Jack Steiner4a7a17c2009-06-17 16:28:25 -0700545 get_clear_fault_map(gru, &imap, &dmap);
Jack Steiner4107e1d2009-12-15 16:48:11 -0800546 gru_dbg(grudev,
547 "cpu %d, chiplet %d, gid %d, imap %016lx %016lx, dmap %016lx %016lx\n",
548 smp_processor_id(), chiplet, gru->gs_gid,
549 imap.fault_bits[0], imap.fault_bits[1],
550 dmap.fault_bits[0], dmap.fault_bits[1]);
Jack Steiner14258642008-07-29 22:33:57 -0700551
Jack Steiner4a7a17c2009-06-17 16:28:25 -0700552 for_each_cbr_in_tfm(cbrnum, dmap.fault_bits) {
Jack Steiner563447d2009-12-15 16:48:12 -0800553 STAT(intr_cbr);
Jack Steiner2ce4d4c2009-12-15 16:48:18 -0800554 cmp = gru->gs_blade->bs_async_wq;
555 if (cmp)
556 complete(cmp);
Jack Steiner4a7a17c2009-06-17 16:28:25 -0700557 gru_dbg(grudev, "gid %d, cbr_done %d, done %d\n",
Jack Steiner2ce4d4c2009-12-15 16:48:18 -0800558 gru->gs_gid, cbrnum, cmp ? cmp->done : -1);
Jack Steiner4a7a17c2009-06-17 16:28:25 -0700559 }
560
561 for_each_cbr_in_tfm(cbrnum, imap.fault_bits) {
Jack Steiner563447d2009-12-15 16:48:12 -0800562 STAT(intr_tfh);
Jack Steiner14258642008-07-29 22:33:57 -0700563 tfh = get_tfh_by_index(gru, cbrnum);
564 prefetchw(tfh); /* Helps on hdw, required for emulator */
565
566 /*
567 * When hardware sets a bit in the faultmap, it implicitly
568 * locks the GRU context so that it cannot be unloaded.
569 * The gts cannot change until a TFH start/writestart command
570 * is issued.
571 */
572 ctxnum = tfh->ctxnum;
573 gts = gru->gs_gts[ctxnum];
574
Jack Steiner2ce4d4c2009-12-15 16:48:18 -0800575 /* Spurious interrupts can cause this. Ignore. */
576 if (!gts) {
577 STAT(intr_spurious);
578 continue;
579 }
580
Jack Steiner14258642008-07-29 22:33:57 -0700581 /*
582 * This is running in interrupt context. Trylock the mmap_sem.
583 * If it fails, retry the fault in user context.
584 */
Jack Steiner5958ab82009-12-15 16:48:18 -0800585 gts->ustats.fmm_tlbmiss++;
Jack Steinercd1334f2009-06-17 16:28:19 -0700586 if (!gts->ts_force_cch_reload &&
587 down_read_trylock(&gts->ts_mm->mmap_sem)) {
Jack Steiner2ce4d4c2009-12-15 16:48:18 -0800588 gru_try_dropin(gru, gts, tfh, NULL);
Jack Steiner14258642008-07-29 22:33:57 -0700589 up_read(&gts->ts_mm->mmap_sem);
590 } else {
591 tfh_user_polling_mode(tfh);
Jack Steiner43884602009-04-02 16:59:05 -0700592 STAT(intr_mm_lock_failed);
Jack Steiner14258642008-07-29 22:33:57 -0700593 }
594 }
595 return IRQ_HANDLED;
596}
597
Jack Steiner4107e1d2009-12-15 16:48:11 -0800598irqreturn_t gru0_intr(int irq, void *dev_id)
599{
600 return gru_intr(0, uv_numa_blade_id());
601}
602
603irqreturn_t gru1_intr(int irq, void *dev_id)
604{
605 return gru_intr(1, uv_numa_blade_id());
606}
607
608irqreturn_t gru_intr_mblade(int irq, void *dev_id)
609{
610 int blade;
611
612 for_each_possible_blade(blade) {
613 if (uv_blade_nr_possible_cpus(blade))
614 continue;
615 gru_intr(0, blade);
616 gru_intr(1, blade);
617 }
618 return IRQ_HANDLED;
619}
620
Jack Steiner14258642008-07-29 22:33:57 -0700621
622static int gru_user_dropin(struct gru_thread_state *gts,
623 struct gru_tlb_fault_handle *tfh,
Jack Steinerb61fc692009-12-15 16:48:03 -0800624 void *cb)
Jack Steiner14258642008-07-29 22:33:57 -0700625{
626 struct gru_mm_struct *gms = gts->ts_gms;
627 int ret;
628
Jack Steiner5958ab82009-12-15 16:48:18 -0800629 gts->ustats.upm_tlbmiss++;
Jack Steiner14258642008-07-29 22:33:57 -0700630 while (1) {
631 wait_event(gms->ms_wait_queue,
632 atomic_read(&gms->ms_range_active) == 0);
633 prefetchw(tfh); /* Helps on hdw, required for emulator */
Jack Steiner2ce4d4c2009-12-15 16:48:18 -0800634 ret = gru_try_dropin(gts->ts_gru, gts, tfh, cb);
Jack Steiner14258642008-07-29 22:33:57 -0700635 if (ret <= 0)
636 return ret;
637 STAT(call_os_wait_queue);
638 }
639}
640
641/*
642 * This interface is called as a result of a user detecting a "call OS" bit
643 * in a user CB. Normally means that a TLB fault has occurred.
644 * cb - user virtual address of the CB
645 */
646int gru_handle_user_call_os(unsigned long cb)
647{
648 struct gru_tlb_fault_handle *tfh;
649 struct gru_thread_state *gts;
Jack Steinerb61fc692009-12-15 16:48:03 -0800650 void *cbk;
Jack Steiner14258642008-07-29 22:33:57 -0700651 int ucbnum, cbrnum, ret = -EINVAL;
652
653 STAT(call_os);
Jack Steiner14258642008-07-29 22:33:57 -0700654
655 /* sanity check the cb pointer */
656 ucbnum = get_cb_number((void *)cb);
657 if ((cb & (GRU_HANDLE_STRIDE - 1)) || ucbnum >= GRU_NUM_CB)
658 return -EINVAL;
Jack Steiner14258642008-07-29 22:33:57 -0700659
660 gts = gru_find_lock_gts(cb);
661 if (!gts)
662 return -EINVAL;
Jack Steiner563447d2009-12-15 16:48:12 -0800663 gru_dbg(grudev, "address 0x%lx, gid %d, gts 0x%p\n", cb, gts->ts_gru ? gts->ts_gru->gs_gid : -1, gts);
Jack Steiner14258642008-07-29 22:33:57 -0700664
Jack Steinerfe5bb6b2009-04-02 16:59:04 -0700665 if (ucbnum >= gts->ts_cbr_au_count * GRU_CBR_AU_SIZE)
Jack Steiner14258642008-07-29 22:33:57 -0700666 goto exit;
Jack Steiner14258642008-07-29 22:33:57 -0700667
Jack Steiner55484c42009-12-15 16:48:05 -0800668 gru_check_context_placement(gts);
Jack Steinerfe5bb6b2009-04-02 16:59:04 -0700669
Jack Steiner7b8274e2009-04-02 16:59:12 -0700670 /*
671 * CCH may contain stale data if ts_force_cch_reload is set.
672 */
673 if (gts->ts_gru && gts->ts_force_cch_reload) {
Jack Steiner7b8274e2009-04-02 16:59:12 -0700674 gts->ts_force_cch_reload = 0;
Jack Steiner99f7c222009-12-15 16:48:06 -0800675 gru_update_cch(gts);
Jack Steiner7b8274e2009-04-02 16:59:12 -0700676 }
677
Jack Steiner14258642008-07-29 22:33:57 -0700678 ret = -EAGAIN;
679 cbrnum = thread_cbr_number(gts, ucbnum);
Jack Steiner99f7c222009-12-15 16:48:06 -0800680 if (gts->ts_gru) {
Jack Steiner14258642008-07-29 22:33:57 -0700681 tfh = get_tfh_by_index(gts->ts_gru, cbrnum);
Jack Steinerb61fc692009-12-15 16:48:03 -0800682 cbk = get_gseg_base_address_cb(gts->ts_gru->gs_gru_base_vaddr,
683 gts->ts_ctxnum, ucbnum);
684 ret = gru_user_dropin(gts, tfh, cbk);
Jack Steiner14258642008-07-29 22:33:57 -0700685 }
686exit:
687 gru_unlock_gts(gts);
688 return ret;
689}
690
691/*
692 * Fetch the exception detail information for a CB that terminated with
693 * an exception.
694 */
695int gru_get_exception_detail(unsigned long arg)
696{
697 struct control_block_extended_exc_detail excdet;
698 struct gru_control_block_extended *cbe;
699 struct gru_thread_state *gts;
700 int ucbnum, cbrnum, ret;
701
702 STAT(user_exception);
703 if (copy_from_user(&excdet, (void __user *)arg, sizeof(excdet)))
704 return -EFAULT;
705
Jack Steiner14258642008-07-29 22:33:57 -0700706 gts = gru_find_lock_gts(excdet.cb);
707 if (!gts)
708 return -EINVAL;
709
Jack Steiner563447d2009-12-15 16:48:12 -0800710 gru_dbg(grudev, "address 0x%lx, gid %d, gts 0x%p\n", excdet.cb, gts->ts_gru ? gts->ts_gru->gs_gid : -1, gts);
Jack Steinerfe5bb6b2009-04-02 16:59:04 -0700711 ucbnum = get_cb_number((void *)excdet.cb);
712 if (ucbnum >= gts->ts_cbr_au_count * GRU_CBR_AU_SIZE) {
713 ret = -EINVAL;
714 } else if (gts->ts_gru) {
Jack Steiner14258642008-07-29 22:33:57 -0700715 cbrnum = thread_cbr_number(gts, ucbnum);
716 cbe = get_cbe_by_index(gts->ts_gru, cbrnum);
Jack Steiner1a2c09e2009-06-17 16:28:28 -0700717 gru_flush_cache(cbe); /* CBE not coherent */
Jack Steiner67bf04a2009-12-15 16:48:11 -0800718 sync_core(); /* make sure we are have current data */
Jack Steiner14258642008-07-29 22:33:57 -0700719 excdet.opc = cbe->opccpy;
720 excdet.exopc = cbe->exopccpy;
721 excdet.ecause = cbe->ecause;
722 excdet.exceptdet0 = cbe->idef1upd;
723 excdet.exceptdet1 = cbe->idef3upd;
Jack Steinercd1334f2009-06-17 16:28:19 -0700724 excdet.cbrstate = cbe->cbrstate;
725 excdet.cbrexecstatus = cbe->cbrexecstatus;
Jack Steinerc5502222009-12-15 16:48:13 -0800726 gru_flush_cache_cbe(cbe);
Jack Steiner14258642008-07-29 22:33:57 -0700727 ret = 0;
728 } else {
729 ret = -EAGAIN;
730 }
731 gru_unlock_gts(gts);
732
Jack Steinercd1334f2009-06-17 16:28:19 -0700733 gru_dbg(grudev,
734 "cb 0x%lx, op %d, exopc %d, cbrstate %d, cbrexecstatus 0x%x, ecause 0x%x, "
735 "exdet0 0x%lx, exdet1 0x%x\n",
736 excdet.cb, excdet.opc, excdet.exopc, excdet.cbrstate, excdet.cbrexecstatus,
737 excdet.ecause, excdet.exceptdet0, excdet.exceptdet1);
Jack Steiner14258642008-07-29 22:33:57 -0700738 if (!ret && copy_to_user((void __user *)arg, &excdet, sizeof(excdet)))
739 ret = -EFAULT;
740 return ret;
741}
742
743/*
744 * User request to unload a context. Content is saved for possible reload.
745 */
Jack Steinerbb04aa72009-04-02 16:59:07 -0700746static int gru_unload_all_contexts(void)
747{
748 struct gru_thread_state *gts;
749 struct gru_state *gru;
Jack Steinere1c32192009-04-02 16:59:10 -0700750 int gid, ctxnum;
Jack Steinerbb04aa72009-04-02 16:59:07 -0700751
752 if (!capable(CAP_SYS_ADMIN))
753 return -EPERM;
Jack Steinere1c32192009-04-02 16:59:10 -0700754 foreach_gid(gid) {
Jack Steinerbb04aa72009-04-02 16:59:07 -0700755 gru = GID_TO_GRU(gid);
756 spin_lock(&gru->gs_lock);
757 for (ctxnum = 0; ctxnum < GRU_NUM_CCH; ctxnum++) {
758 gts = gru->gs_gts[ctxnum];
759 if (gts && mutex_trylock(&gts->ts_ctxlock)) {
760 spin_unlock(&gru->gs_lock);
761 gru_unload_context(gts, 1);
Jack Steinerd57c82b2009-06-17 16:28:20 -0700762 mutex_unlock(&gts->ts_ctxlock);
Jack Steinerbb04aa72009-04-02 16:59:07 -0700763 spin_lock(&gru->gs_lock);
764 }
765 }
766 spin_unlock(&gru->gs_lock);
767 }
768 return 0;
769}
770
Jack Steiner14258642008-07-29 22:33:57 -0700771int gru_user_unload_context(unsigned long arg)
772{
773 struct gru_thread_state *gts;
774 struct gru_unload_context_req req;
775
776 STAT(user_unload_context);
777 if (copy_from_user(&req, (void __user *)arg, sizeof(req)))
778 return -EFAULT;
779
780 gru_dbg(grudev, "gseg 0x%lx\n", req.gseg);
781
Jack Steinerbb04aa72009-04-02 16:59:07 -0700782 if (!req.gseg)
783 return gru_unload_all_contexts();
784
Jack Steiner14258642008-07-29 22:33:57 -0700785 gts = gru_find_lock_gts(req.gseg);
786 if (!gts)
787 return -EINVAL;
788
789 if (gts->ts_gru)
790 gru_unload_context(gts, 1);
791 gru_unlock_gts(gts);
792
793 return 0;
794}
795
796/*
797 * User request to flush a range of virtual addresses from the GRU TLB
798 * (Mainly for testing).
799 */
800int gru_user_flush_tlb(unsigned long arg)
801{
802 struct gru_thread_state *gts;
803 struct gru_flush_tlb_req req;
Jack Steiner1926ee82009-06-17 16:28:33 -0700804 struct gru_mm_struct *gms;
Jack Steiner14258642008-07-29 22:33:57 -0700805
806 STAT(user_flush_tlb);
807 if (copy_from_user(&req, (void __user *)arg, sizeof(req)))
808 return -EFAULT;
809
810 gru_dbg(grudev, "gseg 0x%lx, vaddr 0x%lx, len 0x%lx\n", req.gseg,
811 req.vaddr, req.len);
812
813 gts = gru_find_lock_gts(req.gseg);
814 if (!gts)
815 return -EINVAL;
816
Jack Steiner1926ee82009-06-17 16:28:33 -0700817 gms = gts->ts_gms;
Jack Steiner14258642008-07-29 22:33:57 -0700818 gru_unlock_gts(gts);
Jack Steiner1926ee82009-06-17 16:28:33 -0700819 gru_flush_tlb_range(gms, req.vaddr, req.len);
Jack Steiner14258642008-07-29 22:33:57 -0700820
821 return 0;
822}
823
824/*
Jack Steiner7e796a72009-06-17 16:28:30 -0700825 * Fetch GSEG statisticss
826 */
827long gru_get_gseg_statistics(unsigned long arg)
828{
829 struct gru_thread_state *gts;
830 struct gru_get_gseg_statistics_req req;
831
832 if (copy_from_user(&req, (void __user *)arg, sizeof(req)))
833 return -EFAULT;
834
Jack Steiner091f1a12009-12-15 16:48:02 -0800835 /*
836 * The library creates arrays of contexts for threaded programs.
837 * If no gts exists in the array, the context has never been used & all
838 * statistics are implicitly 0.
839 */
Jack Steiner7e796a72009-06-17 16:28:30 -0700840 gts = gru_find_lock_gts(req.gseg);
841 if (gts) {
842 memcpy(&req.stats, &gts->ustats, sizeof(gts->ustats));
843 gru_unlock_gts(gts);
844 } else {
845 memset(&req.stats, 0, sizeof(gts->ustats));
846 }
847
848 if (copy_to_user((void __user *)arg, &req, sizeof(req)))
849 return -EFAULT;
850
851 return 0;
852}
853
854/*
Jack Steiner14258642008-07-29 22:33:57 -0700855 * Register the current task as the user of the GSEG slice.
856 * Needed for TLB fault interrupt targeting.
857 */
Jack Steiner92b39382009-06-17 16:28:32 -0700858int gru_set_context_option(unsigned long arg)
Jack Steiner14258642008-07-29 22:33:57 -0700859{
860 struct gru_thread_state *gts;
Jack Steiner92b39382009-06-17 16:28:32 -0700861 struct gru_set_context_option_req req;
862 int ret = 0;
Jack Steiner14258642008-07-29 22:33:57 -0700863
Jack Steiner92b39382009-06-17 16:28:32 -0700864 STAT(set_context_option);
865 if (copy_from_user(&req, (void __user *)arg, sizeof(req)))
866 return -EFAULT;
867 gru_dbg(grudev, "op %d, gseg 0x%lx, value1 0x%lx\n", req.op, req.gseg, req.val1);
868
Jack Steinerc5502222009-12-15 16:48:13 -0800869 gts = gru_find_lock_gts(req.gseg);
870 if (!gts) {
871 gts = gru_alloc_locked_gts(req.gseg);
872 if (IS_ERR(gts))
873 return PTR_ERR(gts);
874 }
Jack Steiner14258642008-07-29 22:33:57 -0700875
Jack Steiner92b39382009-06-17 16:28:32 -0700876 switch (req.op) {
Jack Steiner518e5cd2009-12-15 16:48:04 -0800877 case sco_blade_chiplet:
878 /* Select blade/chiplet for GRU context */
879 if (req.val1 < -1 || req.val1 >= GRU_MAX_BLADES || !gru_base[req.val1] ||
880 req.val0 < -1 || req.val0 >= GRU_CHIPLETS_PER_HUB) {
881 ret = -EINVAL;
882 } else {
883 gts->ts_user_blade_id = req.val1;
884 gts->ts_user_chiplet_id = req.val0;
Jack Steiner55484c42009-12-15 16:48:05 -0800885 gru_check_context_placement(gts);
Jack Steiner518e5cd2009-12-15 16:48:04 -0800886 }
887 break;
Jack Steiner92b39382009-06-17 16:28:32 -0700888 case sco_gseg_owner:
889 /* Register the current task as the GSEG owner */
890 gts->ts_tgid_owner = current->tgid;
891 break;
Jack Steinerb1b19fc2009-06-17 16:28:33 -0700892 case sco_cch_req_slice:
893 /* Set the CCH slice option */
894 gts->ts_cch_req_slice = req.val1 & 3;
895 break;
Jack Steiner92b39382009-06-17 16:28:32 -0700896 default:
897 ret = -EINVAL;
898 }
Jack Steiner14258642008-07-29 22:33:57 -0700899 gru_unlock_gts(gts);
900
Jack Steiner92b39382009-06-17 16:28:32 -0700901 return ret;
Jack Steiner14258642008-07-29 22:33:57 -0700902}