1 // SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
2
3 /* Authors: Bernard Metzler <bmt@zurich.ibm.com> */
4 /* Copyright (c) 2008-2019, IBM Corporation */
5
6 #include <linux/gfp.h>
7 #include <rdma/ib_verbs.h>
8 #include <rdma/ib_umem.h>
9 #include <linux/dma-mapping.h>
10 #include <linux/slab.h>
11 #include <linux/sched/mm.h>
12 #include <linux/resource.h>
13
14 #include "siw.h"
15 #include "siw_mem.h"
16
17 /* Stag lookup is based on its index part only (24 bits). */
18 #define SIW_STAG_MAX_INDEX 0x00ffffff
19
20 /*
21 * The code avoids special Stag of zero and tries to randomize
22 * STag values between 1 and SIW_STAG_MAX_INDEX.
23 */
siw_mem_add(struct siw_device * sdev,struct siw_mem * m)24 int siw_mem_add(struct siw_device *sdev, struct siw_mem *m)
25 {
26 struct xa_limit limit = XA_LIMIT(1, SIW_STAG_MAX_INDEX);
27 u32 id, next;
28
29 get_random_bytes(&next, 4);
30 next &= SIW_STAG_MAX_INDEX;
31
32 if (xa_alloc_cyclic(&sdev->mem_xa, &id, m, limit, &next,
33 GFP_KERNEL) < 0)
34 return -ENOMEM;
35
36 /* Set the STag index part */
37 m->stag = id << 8;
38
39 siw_dbg_mem(m, "new MEM object\n");
40
41 return 0;
42 }
43
44 /*
45 * siw_mem_id2obj()
46 *
47 * resolves memory from stag given by id. might be called from:
48 * o process context before sending out of sgl, or
49 * o in softirq when resolving target memory
50 */
siw_mem_id2obj(struct siw_device * sdev,int stag_index)51 struct siw_mem *siw_mem_id2obj(struct siw_device *sdev, int stag_index)
52 {
53 struct siw_mem *mem;
54
55 rcu_read_lock();
56 mem = xa_load(&sdev->mem_xa, stag_index);
57 if (likely(mem && kref_get_unless_zero(&mem->ref))) {
58 rcu_read_unlock();
59 return mem;
60 }
61 rcu_read_unlock();
62
63 return NULL;
64 }
65
siw_umem_release(struct siw_umem * umem)66 void siw_umem_release(struct siw_umem *umem)
67 {
68 int i, num_pages = umem->num_pages;
69
70 if (umem->base_mem)
71 ib_umem_release(umem->base_mem);
72
73 for (i = 0; num_pages > 0; i++) {
74 kfree(umem->page_chunk[i].plist);
75 num_pages -= PAGES_PER_CHUNK;
76 }
77 kfree(umem->page_chunk);
78 kfree(umem);
79 }
80
siw_mr_add_mem(struct siw_mr * mr,struct ib_pd * pd,void * mem_obj,u64 start,u64 len,int rights)81 int siw_mr_add_mem(struct siw_mr *mr, struct ib_pd *pd, void *mem_obj,
82 u64 start, u64 len, int rights)
83 {
84 struct siw_device *sdev = to_siw_dev(pd->device);
85 struct siw_mem *mem = kzalloc(sizeof(*mem), GFP_KERNEL);
86 struct xa_limit limit = XA_LIMIT(1, SIW_STAG_MAX_INDEX);
87 u32 id, next;
88
89 if (!mem)
90 return -ENOMEM;
91
92 mem->mem_obj = mem_obj;
93 mem->stag_valid = 0;
94 mem->sdev = sdev;
95 mem->va = start;
96 mem->len = len;
97 mem->pd = pd;
98 mem->perms = rights & IWARP_ACCESS_MASK;
99 kref_init(&mem->ref);
100
101 get_random_bytes(&next, 4);
102 next &= SIW_STAG_MAX_INDEX;
103
104 if (xa_alloc_cyclic(&sdev->mem_xa, &id, mem, limit, &next,
105 GFP_KERNEL) < 0) {
106 kfree(mem);
107 return -ENOMEM;
108 }
109
110 mr->mem = mem;
111 /* Set the STag index part */
112 mem->stag = id << 8;
113 mr->base_mr.lkey = mr->base_mr.rkey = mem->stag;
114
115 return 0;
116 }
117
siw_mr_drop_mem(struct siw_mr * mr)118 void siw_mr_drop_mem(struct siw_mr *mr)
119 {
120 struct siw_mem *mem = mr->mem, *found;
121
122 mem->stag_valid = 0;
123
124 /* make STag invalid visible asap */
125 smp_mb();
126
127 found = xa_erase(&mem->sdev->mem_xa, mem->stag >> 8);
128 WARN_ON(found != mem);
129 siw_mem_put(mem);
130 }
131
siw_free_mem(struct kref * ref)132 void siw_free_mem(struct kref *ref)
133 {
134 struct siw_mem *mem = container_of(ref, struct siw_mem, ref);
135
136 siw_dbg_mem(mem, "free mem, pbl: %s\n", mem->is_pbl ? "y" : "n");
137
138 if (!mem->is_mw && mem->mem_obj) {
139 if (mem->is_pbl == 0)
140 siw_umem_release(mem->umem);
141 else
142 kfree(mem->pbl);
143 }
144 kfree(mem);
145 }
146
147 /*
148 * siw_check_mem()
149 *
150 * Check protection domain, STAG state, access permissions and
151 * address range for memory object.
152 *
153 * @pd: Protection Domain memory should belong to
154 * @mem: memory to be checked
155 * @addr: starting addr of mem
156 * @perms: requested access permissions
157 * @len: len of memory interval to be checked
158 *
159 */
siw_check_mem(struct ib_pd * pd,struct siw_mem * mem,u64 addr,enum ib_access_flags perms,int len)160 int siw_check_mem(struct ib_pd *pd, struct siw_mem *mem, u64 addr,
161 enum ib_access_flags perms, int len)
162 {
163 if (!mem->stag_valid) {
164 siw_dbg_pd(pd, "STag 0x%08x invalid\n", mem->stag);
165 return -E_STAG_INVALID;
166 }
167 if (mem->pd != pd) {
168 siw_dbg_pd(pd, "STag 0x%08x: PD mismatch\n", mem->stag);
169 return -E_PD_MISMATCH;
170 }
171 /*
172 * check access permissions
173 */
174 if ((mem->perms & perms) < perms) {
175 siw_dbg_pd(pd, "permissions 0x%08x < 0x%08x\n",
176 mem->perms, perms);
177 return -E_ACCESS_PERM;
178 }
179 /*
180 * Check if access falls into valid memory interval.
181 */
182 if (addr < mem->va || addr + len > mem->va + mem->len) {
183 siw_dbg_pd(pd, "MEM interval len %d\n", len);
184 siw_dbg_pd(pd, "[0x%pK, 0x%pK] out of bounds\n",
185 (void *)(uintptr_t)addr,
186 (void *)(uintptr_t)(addr + len));
187 siw_dbg_pd(pd, "[0x%pK, 0x%pK] STag=0x%08x\n",
188 (void *)(uintptr_t)mem->va,
189 (void *)(uintptr_t)(mem->va + mem->len),
190 mem->stag);
191
192 return -E_BASE_BOUNDS;
193 }
194 return E_ACCESS_OK;
195 }
196
197 /*
198 * siw_check_sge()
199 *
200 * Check SGE for access rights in given interval
201 *
202 * @pd: Protection Domain memory should belong to
203 * @sge: SGE to be checked
204 * @mem: location of memory reference within array
205 * @perms: requested access permissions
206 * @off: starting offset in SGE
207 * @len: len of memory interval to be checked
208 *
209 * NOTE: Function references SGE's memory object (mem->obj)
210 * if not yet done. New reference is kept if check went ok and
211 * released if check failed. If mem->obj is already valid, no new
212 * lookup is being done and mem is not released it check fails.
213 */
siw_check_sge(struct ib_pd * pd,struct siw_sge * sge,struct siw_mem * mem[],enum ib_access_flags perms,u32 off,int len)214 int siw_check_sge(struct ib_pd *pd, struct siw_sge *sge, struct siw_mem *mem[],
215 enum ib_access_flags perms, u32 off, int len)
216 {
217 struct siw_device *sdev = to_siw_dev(pd->device);
218 struct siw_mem *new = NULL;
219 int rv = E_ACCESS_OK;
220
221 if (len + off > sge->length) {
222 rv = -E_BASE_BOUNDS;
223 goto fail;
224 }
225 if (*mem == NULL) {
226 new = siw_mem_id2obj(sdev, sge->lkey >> 8);
227 if (unlikely(!new)) {
228 siw_dbg_pd(pd, "STag unknown: 0x%08x\n", sge->lkey);
229 rv = -E_STAG_INVALID;
230 goto fail;
231 }
232 *mem = new;
233 }
234 /* Check if user re-registered with different STag key */
235 if (unlikely((*mem)->stag != sge->lkey)) {
236 siw_dbg_mem((*mem), "STag mismatch: 0x%08x\n", sge->lkey);
237 rv = -E_STAG_INVALID;
238 goto fail;
239 }
240 rv = siw_check_mem(pd, *mem, sge->laddr + off, perms, len);
241 if (unlikely(rv))
242 goto fail;
243
244 return 0;
245
246 fail:
247 if (new) {
248 *mem = NULL;
249 siw_mem_put(new);
250 }
251 return rv;
252 }
253
siw_wqe_put_mem(struct siw_wqe * wqe,enum siw_opcode op)254 void siw_wqe_put_mem(struct siw_wqe *wqe, enum siw_opcode op)
255 {
256 switch (op) {
257 case SIW_OP_SEND:
258 case SIW_OP_WRITE:
259 case SIW_OP_SEND_WITH_IMM:
260 case SIW_OP_SEND_REMOTE_INV:
261 case SIW_OP_READ:
262 case SIW_OP_READ_LOCAL_INV:
263 if (!(wqe->sqe.flags & SIW_WQE_INLINE))
264 siw_unref_mem_sgl(wqe->mem, wqe->sqe.num_sge);
265 break;
266
267 case SIW_OP_RECEIVE:
268 siw_unref_mem_sgl(wqe->mem, wqe->rqe.num_sge);
269 break;
270
271 case SIW_OP_READ_RESPONSE:
272 siw_unref_mem_sgl(wqe->mem, 1);
273 break;
274
275 default:
276 /*
277 * SIW_OP_INVAL_STAG and SIW_OP_REG_MR
278 * do not hold memory references
279 */
280 break;
281 }
282 }
283
siw_invalidate_stag(struct ib_pd * pd,u32 stag)284 int siw_invalidate_stag(struct ib_pd *pd, u32 stag)
285 {
286 struct siw_device *sdev = to_siw_dev(pd->device);
287 struct siw_mem *mem = siw_mem_id2obj(sdev, stag >> 8);
288 int rv = 0;
289
290 if (unlikely(!mem)) {
291 siw_dbg_pd(pd, "STag 0x%08x unknown\n", stag);
292 return -EINVAL;
293 }
294 if (unlikely(mem->pd != pd)) {
295 siw_dbg_pd(pd, "PD mismatch for STag 0x%08x\n", stag);
296 rv = -EACCES;
297 goto out;
298 }
299 /*
300 * Per RDMA verbs definition, an STag may already be in invalid
301 * state if invalidation is requested. So no state check here.
302 */
303 mem->stag_valid = 0;
304
305 siw_dbg_pd(pd, "STag 0x%08x now invalid\n", stag);
306 out:
307 siw_mem_put(mem);
308 return rv;
309 }
310
311 /*
312 * Gets physical address backed by PBL element. Address is referenced
313 * by linear byte offset into list of variably sized PB elements.
314 * Optionally, provides remaining len within current element, and
315 * current PBL index for later resume at same element.
316 */
siw_pbl_get_buffer(struct siw_pbl * pbl,u64 off,int * len,int * idx)317 dma_addr_t siw_pbl_get_buffer(struct siw_pbl *pbl, u64 off, int *len, int *idx)
318 {
319 int i = idx ? *idx : 0;
320
321 while (i < pbl->num_buf) {
322 struct siw_pble *pble = &pbl->pbe[i];
323
324 if (pble->pbl_off + pble->size > off) {
325 u64 pble_off = off - pble->pbl_off;
326
327 if (len)
328 *len = pble->size - pble_off;
329 if (idx)
330 *idx = i;
331
332 return pble->addr + pble_off;
333 }
334 i++;
335 }
336 if (len)
337 *len = 0;
338 return 0;
339 }
340
siw_pbl_alloc(u32 num_buf)341 struct siw_pbl *siw_pbl_alloc(u32 num_buf)
342 {
343 struct siw_pbl *pbl;
344
345 if (num_buf == 0)
346 return ERR_PTR(-EINVAL);
347
348 pbl = kzalloc(struct_size(pbl, pbe, num_buf), GFP_KERNEL);
349 if (!pbl)
350 return ERR_PTR(-ENOMEM);
351
352 pbl->max_buf = num_buf;
353
354 return pbl;
355 }
356
siw_umem_get(struct ib_device * base_dev,u64 start,u64 len,int rights)357 struct siw_umem *siw_umem_get(struct ib_device *base_dev, u64 start,
358 u64 len, int rights)
359 {
360 struct siw_umem *umem;
361 struct ib_umem *base_mem;
362 struct sg_page_iter sg_iter;
363 struct sg_table *sgt;
364 u64 first_page_va;
365 int num_pages, num_chunks, i, rv = 0;
366
367 if (!len)
368 return ERR_PTR(-EINVAL);
369
370 first_page_va = start & PAGE_MASK;
371 num_pages = PAGE_ALIGN(start + len - first_page_va) >> PAGE_SHIFT;
372 num_chunks = (num_pages >> CHUNK_SHIFT) + 1;
373
374 umem = kzalloc(sizeof(*umem), GFP_KERNEL);
375 if (!umem)
376 return ERR_PTR(-ENOMEM);
377
378 umem->page_chunk =
379 kcalloc(num_chunks, sizeof(struct siw_page_chunk), GFP_KERNEL);
380 if (!umem->page_chunk) {
381 rv = -ENOMEM;
382 goto err_out;
383 }
384 base_mem = ib_umem_get(base_dev, start, len, rights);
385 if (IS_ERR(base_mem)) {
386 rv = PTR_ERR(base_mem);
387 siw_dbg(base_dev, "Cannot pin user memory: %d\n", rv);
388 goto err_out;
389 }
390 umem->fp_addr = first_page_va;
391 umem->base_mem = base_mem;
392
393 sgt = &base_mem->sgt_append.sgt;
394 __sg_page_iter_start(&sg_iter, sgt->sgl, sgt->orig_nents, 0);
395
396 if (!__sg_page_iter_next(&sg_iter)) {
397 rv = -EINVAL;
398 goto err_out;
399 }
400 for (i = 0; num_pages > 0; i++) {
401 int nents = min_t(int, num_pages, PAGES_PER_CHUNK);
402 struct page **plist =
403 kcalloc(nents, sizeof(struct page *), GFP_KERNEL);
404
405 if (!plist) {
406 rv = -ENOMEM;
407 goto err_out;
408 }
409 umem->page_chunk[i].plist = plist;
410 while (nents--) {
411 *plist = sg_page_iter_page(&sg_iter);
412 umem->num_pages++;
413 num_pages--;
414 plist++;
415 if (!__sg_page_iter_next(&sg_iter))
416 break;
417 }
418 }
419 return umem;
420 err_out:
421 siw_umem_release(umem);
422
423 return ERR_PTR(rv);
424 }
425