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33#include <linux/types.h>
34#include <linux/kernel.h>
35#include <linux/module.h>
36#include <linux/init.h>
37#include <linux/errno.h>
38#include <linux/miscdevice.h>
39#include <linux/spinlock.h>
40#include <linux/mm.h>
41#include <linux/fs.h>
42#include <linux/vmalloc.h>
43#include <linux/string.h>
44#include <linux/slab.h>
45#include <linux/numa.h>
46#include <asm/page.h>
47#include <asm/system.h>
48#include <asm/pgtable.h>
49#include <asm/atomic.h>
50#include <asm/tlbflush.h>
51#include <asm/uncached.h>
52#include <asm/sn/addrs.h>
53#include <asm/sn/arch.h>
54#include <asm/sn/mspec.h>
55#include <asm/sn/sn_cpuid.h>
56#include <asm/sn/io.h>
57#include <asm/sn/bte.h>
58#include <asm/sn/shubio.h>
59
60
61#define FETCHOP_ID "SGI Fetchop,"
62#define CACHED_ID "Cached,"
63#define UNCACHED_ID "Uncached"
64#define REVISION "4.0"
65#define MSPEC_BASENAME "mspec"
66
67
68
69
70enum mspec_page_type {
71 MSPEC_FETCHOP = 1,
72 MSPEC_CACHED,
73 MSPEC_UNCACHED
74};
75
76#ifdef CONFIG_SGI_SN
77static int is_sn2;
78#else
79#define is_sn2 0
80#endif
81
82
83
84
85
86
87
88
89
90
91
92struct vma_data {
93 atomic_t refcnt;
94 spinlock_t lock;
95 int count;
96 enum mspec_page_type type;
97 int flags;
98 unsigned long vm_start;
99 unsigned long vm_end;
100 unsigned long maddr[0];
101};
102
103#define VMD_VMALLOCED 0x1
104
105
106static unsigned long scratch_page[MAX_NUMNODES];
107#define SH2_AMO_CACHE_ENTRIES 4
108
109static inline int
110mspec_zero_block(unsigned long addr, int len)
111{
112 int status;
113
114 if (is_sn2) {
115 if (is_shub2()) {
116 int nid;
117 void *p;
118 int i;
119
120 nid = nasid_to_cnodeid(get_node_number(__pa(addr)));
121 p = (void *)TO_AMO(scratch_page[nid]);
122
123 for (i=0; i < SH2_AMO_CACHE_ENTRIES; i++) {
124 FETCHOP_LOAD_OP(p, FETCHOP_LOAD);
125 p += FETCHOP_VAR_SIZE;
126 }
127 }
128
129 status = bte_copy(0, addr & ~__IA64_UNCACHED_OFFSET, len,
130 BTE_WACQUIRE | BTE_ZERO_FILL, NULL);
131 } else {
132 memset((char *) addr, 0, len);
133 status = 0;
134 }
135 return status;
136}
137
138
139
140
141
142
143
144
145static void
146mspec_open(struct vm_area_struct *vma)
147{
148 struct vma_data *vdata;
149
150 vdata = vma->vm_private_data;
151 atomic_inc(&vdata->refcnt);
152}
153
154
155
156
157
158
159
160static void
161mspec_close(struct vm_area_struct *vma)
162{
163 struct vma_data *vdata;
164 int index, last_index;
165 unsigned long my_page;
166
167 vdata = vma->vm_private_data;
168
169 if (!atomic_dec_and_test(&vdata->refcnt))
170 return;
171
172 last_index = (vdata->vm_end - vdata->vm_start) >> PAGE_SHIFT;
173 for (index = 0; index < last_index; index++) {
174 if (vdata->maddr[index] == 0)
175 continue;
176
177
178
179
180 my_page = vdata->maddr[index];
181 vdata->maddr[index] = 0;
182 if (!mspec_zero_block(my_page, PAGE_SIZE))
183 uncached_free_page(my_page, 1);
184 else
185 printk(KERN_WARNING "mspec_close(): "
186 "failed to zero page %ld\n", my_page);
187 }
188
189 if (vdata->flags & VMD_VMALLOCED)
190 vfree(vdata);
191 else
192 kfree(vdata);
193}
194
195
196
197
198
199
200static int
201mspec_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
202{
203 unsigned long paddr, maddr;
204 unsigned long pfn;
205 pgoff_t index = vmf->pgoff;
206 struct vma_data *vdata = vma->vm_private_data;
207
208 maddr = (volatile unsigned long) vdata->maddr[index];
209 if (maddr == 0) {
210 maddr = uncached_alloc_page(numa_node_id(), 1);
211 if (maddr == 0)
212 return VM_FAULT_OOM;
213
214 spin_lock(&vdata->lock);
215 if (vdata->maddr[index] == 0) {
216 vdata->count++;
217 vdata->maddr[index] = maddr;
218 } else {
219 uncached_free_page(maddr, 1);
220 maddr = vdata->maddr[index];
221 }
222 spin_unlock(&vdata->lock);
223 }
224
225 if (vdata->type == MSPEC_FETCHOP)
226 paddr = TO_AMO(maddr);
227 else
228 paddr = maddr & ~__IA64_UNCACHED_OFFSET;
229
230 pfn = paddr >> PAGE_SHIFT;
231
232
233
234
235
236
237 vm_insert_pfn(vma, (unsigned long)vmf->virtual_address, pfn);
238
239 return VM_FAULT_NOPAGE;
240}
241
242static const struct vm_operations_struct mspec_vm_ops = {
243 .open = mspec_open,
244 .close = mspec_close,
245 .fault = mspec_fault,
246};
247
248
249
250
251
252
253
254
255static int
256mspec_mmap(struct file *file, struct vm_area_struct *vma,
257 enum mspec_page_type type)
258{
259 struct vma_data *vdata;
260 int pages, vdata_size, flags = 0;
261
262 if (vma->vm_pgoff != 0)
263 return -EINVAL;
264
265 if ((vma->vm_flags & VM_SHARED) == 0)
266 return -EINVAL;
267
268 if ((vma->vm_flags & VM_WRITE) == 0)
269 return -EPERM;
270
271 pages = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
272 vdata_size = sizeof(struct vma_data) + pages * sizeof(long);
273 if (vdata_size <= PAGE_SIZE)
274 vdata = kmalloc(vdata_size, GFP_KERNEL);
275 else {
276 vdata = vmalloc(vdata_size);
277 flags = VMD_VMALLOCED;
278 }
279 if (!vdata)
280 return -ENOMEM;
281 memset(vdata, 0, vdata_size);
282
283 vdata->vm_start = vma->vm_start;
284 vdata->vm_end = vma->vm_end;
285 vdata->flags = flags;
286 vdata->type = type;
287 spin_lock_init(&vdata->lock);
288 vdata->refcnt = ATOMIC_INIT(1);
289 vma->vm_private_data = vdata;
290
291 vma->vm_flags |= (VM_IO | VM_RESERVED | VM_PFNMAP | VM_DONTEXPAND);
292 if (vdata->type == MSPEC_FETCHOP || vdata->type == MSPEC_UNCACHED)
293 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
294 vma->vm_ops = &mspec_vm_ops;
295
296 return 0;
297}
298
299static int
300fetchop_mmap(struct file *file, struct vm_area_struct *vma)
301{
302 return mspec_mmap(file, vma, MSPEC_FETCHOP);
303}
304
305static int
306cached_mmap(struct file *file, struct vm_area_struct *vma)
307{
308 return mspec_mmap(file, vma, MSPEC_CACHED);
309}
310
311static int
312uncached_mmap(struct file *file, struct vm_area_struct *vma)
313{
314 return mspec_mmap(file, vma, MSPEC_UNCACHED);
315}
316
317static const struct file_operations fetchop_fops = {
318 .owner = THIS_MODULE,
319 .mmap = fetchop_mmap,
320 .llseek = noop_llseek,
321};
322
323static struct miscdevice fetchop_miscdev = {
324 .minor = MISC_DYNAMIC_MINOR,
325 .name = "sgi_fetchop",
326 .fops = &fetchop_fops
327};
328
329static const struct file_operations cached_fops = {
330 .owner = THIS_MODULE,
331 .mmap = cached_mmap,
332 .llseek = noop_llseek,
333};
334
335static struct miscdevice cached_miscdev = {
336 .minor = MISC_DYNAMIC_MINOR,
337 .name = "mspec_cached",
338 .fops = &cached_fops
339};
340
341static const struct file_operations uncached_fops = {
342 .owner = THIS_MODULE,
343 .mmap = uncached_mmap,
344 .llseek = noop_llseek,
345};
346
347static struct miscdevice uncached_miscdev = {
348 .minor = MISC_DYNAMIC_MINOR,
349 .name = "mspec_uncached",
350 .fops = &uncached_fops
351};
352
353
354
355
356
357
358static int __init
359mspec_init(void)
360{
361 int ret;
362 int nid;
363
364
365
366
367
368#ifdef CONFIG_SGI_SN
369 if (ia64_platform_is("sn2")) {
370 is_sn2 = 1;
371 if (is_shub2()) {
372 ret = -ENOMEM;
373 for_each_node_state(nid, N_ONLINE) {
374 int actual_nid;
375 int nasid;
376 unsigned long phys;
377
378 scratch_page[nid] = uncached_alloc_page(nid, 1);
379 if (scratch_page[nid] == 0)
380 goto free_scratch_pages;
381 phys = __pa(scratch_page[nid]);
382 nasid = get_node_number(phys);
383 actual_nid = nasid_to_cnodeid(nasid);
384 if (actual_nid != nid)
385 goto free_scratch_pages;
386 }
387 }
388
389 ret = misc_register(&fetchop_miscdev);
390 if (ret) {
391 printk(KERN_ERR
392 "%s: failed to register device %i\n",
393 FETCHOP_ID, ret);
394 goto free_scratch_pages;
395 }
396 }
397#endif
398 ret = misc_register(&cached_miscdev);
399 if (ret) {
400 printk(KERN_ERR "%s: failed to register device %i\n",
401 CACHED_ID, ret);
402 if (is_sn2)
403 misc_deregister(&fetchop_miscdev);
404 goto free_scratch_pages;
405 }
406 ret = misc_register(&uncached_miscdev);
407 if (ret) {
408 printk(KERN_ERR "%s: failed to register device %i\n",
409 UNCACHED_ID, ret);
410 misc_deregister(&cached_miscdev);
411 if (is_sn2)
412 misc_deregister(&fetchop_miscdev);
413 goto free_scratch_pages;
414 }
415
416 printk(KERN_INFO "%s %s initialized devices: %s %s %s\n",
417 MSPEC_BASENAME, REVISION, is_sn2 ? FETCHOP_ID : "",
418 CACHED_ID, UNCACHED_ID);
419
420 return 0;
421
422 free_scratch_pages:
423 for_each_node(nid) {
424 if (scratch_page[nid] != 0)
425 uncached_free_page(scratch_page[nid], 1);
426 }
427 return ret;
428}
429
430static void __exit
431mspec_exit(void)
432{
433 int nid;
434
435 misc_deregister(&uncached_miscdev);
436 misc_deregister(&cached_miscdev);
437 if (is_sn2) {
438 misc_deregister(&fetchop_miscdev);
439
440 for_each_node(nid) {
441 if (scratch_page[nid] != 0)
442 uncached_free_page(scratch_page[nid], 1);
443 }
444 }
445}
446
447module_init(mspec_init);
448module_exit(mspec_exit);
449
450MODULE_AUTHOR("Silicon Graphics, Inc. <linux-altix@sgi.com>");
451MODULE_DESCRIPTION("Driver for SGI SN special memory operations");
452MODULE_LICENSE("GPL");
453