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15#include <linux/types.h>
16#include <linux/kernel.h>
17#include <linux/module.h>
18#include <linux/init.h>
19#include <linux/errno.h>
20#include <linux/string.h>
21#include <linux/slab.h>
22#include <linux/efi.h>
23#include <linux/genalloc.h>
24#include <asm/page.h>
25#include <asm/pal.h>
26#include <asm/system.h>
27#include <asm/pgtable.h>
28#include <asm/atomic.h>
29#include <asm/tlbflush.h>
30#include <asm/sn/arch.h>
31
32
33extern void __init efi_memmap_walk_uc(efi_freemem_callback_t, void *);
34
35struct uncached_pool {
36 struct gen_pool *pool;
37 struct mutex add_chunk_mutex;
38 int nchunks_added;
39 atomic_t status;
40};
41
42#define MAX_CONVERTED_CHUNKS_PER_NODE 2
43
44struct uncached_pool uncached_pools[MAX_NUMNODES];
45
46
47static void uncached_ipi_visibility(void *data)
48{
49 int status;
50 struct uncached_pool *uc_pool = (struct uncached_pool *)data;
51
52 status = ia64_pal_prefetch_visibility(PAL_VISIBILITY_PHYSICAL);
53 if ((status != PAL_VISIBILITY_OK) &&
54 (status != PAL_VISIBILITY_OK_REMOTE_NEEDED))
55 atomic_inc(&uc_pool->status);
56}
57
58
59static void uncached_ipi_mc_drain(void *data)
60{
61 int status;
62 struct uncached_pool *uc_pool = (struct uncached_pool *)data;
63
64 status = ia64_pal_mc_drain();
65 if (status != PAL_STATUS_SUCCESS)
66 atomic_inc(&uc_pool->status);
67}
68
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77
78
79static int uncached_add_chunk(struct uncached_pool *uc_pool, int nid)
80{
81 struct page *page;
82 int status, i, nchunks_added = uc_pool->nchunks_added;
83 unsigned long c_addr, uc_addr;
84
85 if (mutex_lock_interruptible(&uc_pool->add_chunk_mutex) != 0)
86 return -1;
87
88 if (uc_pool->nchunks_added > nchunks_added) {
89
90 mutex_unlock(&uc_pool->add_chunk_mutex);
91 return 0;
92 }
93
94 if (uc_pool->nchunks_added >= MAX_CONVERTED_CHUNKS_PER_NODE) {
95 mutex_unlock(&uc_pool->add_chunk_mutex);
96 return -1;
97 }
98
99
100
101 page = alloc_pages_exact_node(nid,
102 GFP_KERNEL | __GFP_ZERO | GFP_THISNODE,
103 IA64_GRANULE_SHIFT-PAGE_SHIFT);
104 if (!page) {
105 mutex_unlock(&uc_pool->add_chunk_mutex);
106 return -1;
107 }
108
109
110
111 c_addr = (unsigned long)page_address(page);
112 uc_addr = c_addr - PAGE_OFFSET + __IA64_UNCACHED_OFFSET;
113
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117
118
119 for (i = 0; i < (IA64_GRANULE_SIZE / PAGE_SIZE); i++)
120 SetPageUncached(&page[i]);
121
122 flush_tlb_kernel_range(uc_addr, uc_addr + IA64_GRANULE_SIZE);
123
124 status = ia64_pal_prefetch_visibility(PAL_VISIBILITY_PHYSICAL);
125 if (status == PAL_VISIBILITY_OK_REMOTE_NEEDED) {
126 atomic_set(&uc_pool->status, 0);
127 status = smp_call_function(uncached_ipi_visibility, uc_pool, 1);
128 if (status || atomic_read(&uc_pool->status))
129 goto failed;
130 } else if (status != PAL_VISIBILITY_OK)
131 goto failed;
132
133 preempt_disable();
134
135 if (ia64_platform_is("sn2"))
136 sn_flush_all_caches(uc_addr, IA64_GRANULE_SIZE);
137 else
138 flush_icache_range(uc_addr, uc_addr + IA64_GRANULE_SIZE);
139
140
141 local_flush_tlb_all();
142
143 preempt_enable();
144
145 status = ia64_pal_mc_drain();
146 if (status != PAL_STATUS_SUCCESS)
147 goto failed;
148 atomic_set(&uc_pool->status, 0);
149 status = smp_call_function(uncached_ipi_mc_drain, uc_pool, 1);
150 if (status || atomic_read(&uc_pool->status))
151 goto failed;
152
153
154
155
156
157 status = gen_pool_add(uc_pool->pool, uc_addr, IA64_GRANULE_SIZE, nid);
158 if (status)
159 goto failed;
160
161 uc_pool->nchunks_added++;
162 mutex_unlock(&uc_pool->add_chunk_mutex);
163 return 0;
164
165
166failed:
167 for (i = 0; i < (IA64_GRANULE_SIZE / PAGE_SIZE); i++)
168 ClearPageUncached(&page[i]);
169
170 free_pages(c_addr, IA64_GRANULE_SHIFT-PAGE_SHIFT);
171 mutex_unlock(&uc_pool->add_chunk_mutex);
172 return -1;
173}
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184
185
186unsigned long uncached_alloc_page(int starting_nid, int n_pages)
187{
188 unsigned long uc_addr;
189 struct uncached_pool *uc_pool;
190 int nid;
191
192 if (unlikely(starting_nid >= MAX_NUMNODES))
193 return 0;
194
195 if (starting_nid < 0)
196 starting_nid = numa_node_id();
197 nid = starting_nid;
198
199 do {
200 if (!node_state(nid, N_HIGH_MEMORY))
201 continue;
202 uc_pool = &uncached_pools[nid];
203 if (uc_pool->pool == NULL)
204 continue;
205 do {
206 uc_addr = gen_pool_alloc(uc_pool->pool,
207 n_pages * PAGE_SIZE);
208 if (uc_addr != 0)
209 return uc_addr;
210 } while (uncached_add_chunk(uc_pool, nid) == 0);
211
212 } while ((nid = (nid + 1) % MAX_NUMNODES) != starting_nid);
213
214 return 0;
215}
216EXPORT_SYMBOL(uncached_alloc_page);
217
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226
227void uncached_free_page(unsigned long uc_addr, int n_pages)
228{
229 int nid = paddr_to_nid(uc_addr - __IA64_UNCACHED_OFFSET);
230 struct gen_pool *pool = uncached_pools[nid].pool;
231
232 if (unlikely(pool == NULL))
233 return;
234
235 if ((uc_addr & (0XFUL << 60)) != __IA64_UNCACHED_OFFSET)
236 panic("uncached_free_page invalid address %lx\n", uc_addr);
237
238 gen_pool_free(pool, uc_addr, n_pages * PAGE_SIZE);
239}
240EXPORT_SYMBOL(uncached_free_page);
241
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252
253static int __init uncached_build_memmap(u64 uc_start, u64 uc_end, void *arg)
254{
255 int nid = paddr_to_nid(uc_start - __IA64_UNCACHED_OFFSET);
256 struct gen_pool *pool = uncached_pools[nid].pool;
257 size_t size = uc_end - uc_start;
258
259 touch_softlockup_watchdog();
260
261 if (pool != NULL) {
262 memset((char *)uc_start, 0, size);
263 (void) gen_pool_add(pool, uc_start, size, nid);
264 }
265 return 0;
266}
267
268
269static int __init uncached_init(void)
270{
271 int nid;
272
273 for_each_node_state(nid, N_ONLINE) {
274 uncached_pools[nid].pool = gen_pool_create(PAGE_SHIFT, nid);
275 mutex_init(&uncached_pools[nid].add_chunk_mutex);
276 }
277
278 efi_memmap_walk_uc(uncached_build_memmap, NULL);
279 return 0;
280}
281
282__initcall(uncached_init);
283