contigmem: cleanup properly when load fails
[dpdk.git] / kernel / freebsd / contigmem / contigmem.c
1 /* SPDX-License-Identifier: BSD-3-Clause
2  * Copyright(c) 2010-2014 Intel Corporation
3  */
4
5 #include <sys/cdefs.h>
6 __FBSDID("$FreeBSD$");
7
8 #include <sys/param.h>
9 #include <sys/bio.h>
10 #include <sys/bus.h>
11 #include <sys/conf.h>
12 #include <sys/kernel.h>
13 #include <sys/malloc.h>
14 #include <sys/module.h>
15 #include <sys/proc.h>
16 #include <sys/lock.h>
17 #include <sys/rwlock.h>
18 #include <sys/mutex.h>
19 #include <sys/systm.h>
20 #include <sys/sysctl.h>
21 #include <sys/vmmeter.h>
22 #include <sys/eventhandler.h>
23
24 #include <machine/bus.h>
25
26 #include <vm/vm.h>
27 #include <vm/pmap.h>
28 #include <vm/vm_param.h>
29 #include <vm/vm_object.h>
30 #include <vm/vm_page.h>
31 #include <vm/vm_pager.h>
32 #include <vm/vm_phys.h>
33
34 struct contigmem_buffer {
35         void           *addr;
36         int             refcnt;
37         struct mtx      mtx;
38 };
39
40 struct contigmem_vm_handle {
41         int             buffer_index;
42 };
43
44 static int              contigmem_load(void);
45 static int              contigmem_unload(void);
46 static int              contigmem_physaddr(SYSCTL_HANDLER_ARGS);
47
48 static d_mmap_single_t  contigmem_mmap_single;
49 static d_open_t         contigmem_open;
50 static d_close_t        contigmem_close;
51
52 static int              contigmem_num_buffers = RTE_CONTIGMEM_DEFAULT_NUM_BUFS;
53 static int64_t          contigmem_buffer_size = RTE_CONTIGMEM_DEFAULT_BUF_SIZE;
54
55 static eventhandler_tag contigmem_eh_tag;
56 static struct contigmem_buffer contigmem_buffers[RTE_CONTIGMEM_MAX_NUM_BUFS];
57 static struct cdev     *contigmem_cdev = NULL;
58 static int              contigmem_refcnt;
59
60 TUNABLE_INT("hw.contigmem.num_buffers", &contigmem_num_buffers);
61 TUNABLE_QUAD("hw.contigmem.buffer_size", &contigmem_buffer_size);
62
63 static SYSCTL_NODE(_hw, OID_AUTO, contigmem, CTLFLAG_RD, 0, "contigmem");
64
65 SYSCTL_INT(_hw_contigmem, OID_AUTO, num_buffers, CTLFLAG_RD,
66         &contigmem_num_buffers, 0, "Number of contigmem buffers allocated");
67 SYSCTL_QUAD(_hw_contigmem, OID_AUTO, buffer_size, CTLFLAG_RD,
68         &contigmem_buffer_size, 0, "Size of each contiguous buffer");
69 SYSCTL_INT(_hw_contigmem, OID_AUTO, num_references, CTLFLAG_RD,
70         &contigmem_refcnt, 0, "Number of references to contigmem");
71
72 static SYSCTL_NODE(_hw_contigmem, OID_AUTO, physaddr, CTLFLAG_RD, 0,
73         "physaddr");
74
75 MALLOC_DEFINE(M_CONTIGMEM, "contigmem", "contigmem(4) allocations");
76
77 static int contigmem_modevent(module_t mod, int type, void *arg)
78 {
79         int error = 0;
80
81         switch (type) {
82         case MOD_LOAD:
83                 error = contigmem_load();
84                 break;
85         case MOD_UNLOAD:
86                 error = contigmem_unload();
87                 break;
88         default:
89                 break;
90         }
91
92         return error;
93 }
94
95 moduledata_t contigmem_mod = {
96         "contigmem",
97         (modeventhand_t)contigmem_modevent,
98         0
99 };
100
101 DECLARE_MODULE(contigmem, contigmem_mod, SI_SUB_DRIVERS, SI_ORDER_ANY);
102 MODULE_VERSION(contigmem, 1);
103
104 static struct cdevsw contigmem_ops = {
105         .d_name         = "contigmem",
106         .d_version      = D_VERSION,
107         .d_flags        = D_TRACKCLOSE,
108         .d_mmap_single  = contigmem_mmap_single,
109         .d_open         = contigmem_open,
110         .d_close        = contigmem_close,
111 };
112
113 static int
114 contigmem_load()
115 {
116         char index_string[8], description[32];
117         int  i, error = 0;
118         void *addr;
119
120         if (contigmem_num_buffers > RTE_CONTIGMEM_MAX_NUM_BUFS) {
121                 printf("%d buffers requested is greater than %d allowed\n",
122                                 contigmem_num_buffers, RTE_CONTIGMEM_MAX_NUM_BUFS);
123                 error = EINVAL;
124                 goto error;
125         }
126
127         if (contigmem_buffer_size < PAGE_SIZE ||
128                         (contigmem_buffer_size & (contigmem_buffer_size - 1)) != 0) {
129                 printf("buffer size 0x%lx is not greater than PAGE_SIZE and "
130                                 "power of two\n", contigmem_buffer_size);
131                 error = EINVAL;
132                 goto error;
133         }
134
135         for (i = 0; i < contigmem_num_buffers; i++) {
136                 addr = contigmalloc(contigmem_buffer_size, M_CONTIGMEM, M_ZERO,
137                         0, BUS_SPACE_MAXADDR, contigmem_buffer_size, 0);
138                 if (addr == NULL) {
139                         printf("contigmalloc failed for buffer %d\n", i);
140                         error = ENOMEM;
141                         goto error;
142                 }
143
144                 printf("%2u: virt=%p phys=%p\n", i, addr,
145                         (void *)pmap_kextract((vm_offset_t)addr));
146
147                 mtx_init(&contigmem_buffers[i].mtx, "contigmem", NULL, MTX_DEF);
148                 contigmem_buffers[i].addr = addr;
149                 contigmem_buffers[i].refcnt = 0;
150
151                 snprintf(index_string, sizeof(index_string), "%d", i);
152                 snprintf(description, sizeof(description),
153                                 "phys addr for buffer %d", i);
154                 SYSCTL_ADD_PROC(NULL,
155                                 &SYSCTL_NODE_CHILDREN(_hw_contigmem, physaddr), OID_AUTO,
156                                 index_string, CTLTYPE_U64 | CTLFLAG_RD,
157                                 (void *)(uintptr_t)i, 0, contigmem_physaddr, "LU",
158                                 description);
159         }
160
161         contigmem_cdev = make_dev_credf(0, &contigmem_ops, 0, NULL, UID_ROOT,
162                         GID_WHEEL, 0600, "contigmem");
163
164         return 0;
165
166 error:
167         for (i = 0; i < contigmem_num_buffers; i++) {
168                 if (contigmem_buffers[i].addr != NULL) {
169                         contigfree(contigmem_buffers[i].addr,
170                                 contigmem_buffer_size, M_CONTIGMEM);
171                         contigmem_buffers[i].addr = NULL;
172                 }
173                 if (mtx_initialized(&contigmem_buffers[i].mtx))
174                         mtx_destroy(&contigmem_buffers[i].mtx);
175         }
176
177         return error;
178 }
179
180 static int
181 contigmem_unload()
182 {
183         int i;
184
185         if (contigmem_refcnt > 0)
186                 return EBUSY;
187
188         if (contigmem_cdev != NULL)
189                 destroy_dev(contigmem_cdev);
190
191         if (contigmem_eh_tag != NULL)
192                 EVENTHANDLER_DEREGISTER(process_exit, contigmem_eh_tag);
193
194         for (i = 0; i < RTE_CONTIGMEM_MAX_NUM_BUFS; i++) {
195                 if (contigmem_buffers[i].addr != NULL)
196                         contigfree(contigmem_buffers[i].addr,
197                                 contigmem_buffer_size, M_CONTIGMEM);
198                 if (mtx_initialized(&contigmem_buffers[i].mtx))
199                         mtx_destroy(&contigmem_buffers[i].mtx);
200         }
201
202         return 0;
203 }
204
205 static int
206 contigmem_physaddr(SYSCTL_HANDLER_ARGS)
207 {
208         uint64_t        physaddr;
209         int             index = (int)(uintptr_t)arg1;
210
211         physaddr = (uint64_t)vtophys(contigmem_buffers[index].addr);
212         return sysctl_handle_64(oidp, &physaddr, 0, req);
213 }
214
215 static int
216 contigmem_open(struct cdev *cdev, int fflags, int devtype,
217                 struct thread *td)
218 {
219
220         atomic_add_int(&contigmem_refcnt, 1);
221
222         return 0;
223 }
224
225 static int
226 contigmem_close(struct cdev *cdev, int fflags, int devtype,
227                 struct thread *td)
228 {
229
230         atomic_subtract_int(&contigmem_refcnt, 1);
231
232         return 0;
233 }
234
235 static int
236 contigmem_cdev_pager_ctor(void *handle, vm_ooffset_t size, vm_prot_t prot,
237                 vm_ooffset_t foff, struct ucred *cred, u_short *color)
238 {
239         struct contigmem_vm_handle *vmh = handle;
240         struct contigmem_buffer *buf;
241
242         buf = &contigmem_buffers[vmh->buffer_index];
243
244         atomic_add_int(&contigmem_refcnt, 1);
245
246         mtx_lock(&buf->mtx);
247         if (buf->refcnt == 0)
248                 memset(buf->addr, 0, contigmem_buffer_size);
249         buf->refcnt++;
250         mtx_unlock(&buf->mtx);
251
252         return 0;
253 }
254
255 static void
256 contigmem_cdev_pager_dtor(void *handle)
257 {
258         struct contigmem_vm_handle *vmh = handle;
259         struct contigmem_buffer *buf;
260
261         buf = &contigmem_buffers[vmh->buffer_index];
262
263         mtx_lock(&buf->mtx);
264         buf->refcnt--;
265         mtx_unlock(&buf->mtx);
266
267         free(vmh, M_CONTIGMEM);
268
269         atomic_subtract_int(&contigmem_refcnt, 1);
270 }
271
272 static int
273 contigmem_cdev_pager_fault(vm_object_t object, vm_ooffset_t offset, int prot,
274                 vm_page_t *mres)
275 {
276         vm_paddr_t paddr;
277         vm_page_t m_paddr, page;
278         vm_memattr_t memattr, memattr1;
279
280         memattr = object->memattr;
281
282         VM_OBJECT_WUNLOCK(object);
283
284         paddr = offset;
285
286         m_paddr = vm_phys_paddr_to_vm_page(paddr);
287         if (m_paddr != NULL) {
288                 memattr1 = pmap_page_get_memattr(m_paddr);
289                 if (memattr1 != memattr)
290                         memattr = memattr1;
291         }
292
293         if (((*mres)->flags & PG_FICTITIOUS) != 0) {
294                 /*
295                  * If the passed in result page is a fake page, update it with
296                  * the new physical address.
297                  */
298                 page = *mres;
299                 VM_OBJECT_WLOCK(object);
300                 vm_page_updatefake(page, paddr, memattr);
301         } else {
302                 /*
303                  * Replace the passed in reqpage page with our own fake page and
304                  * free up the original page.
305                  */
306                 page = vm_page_getfake(paddr, memattr);
307                 VM_OBJECT_WLOCK(object);
308 #if __FreeBSD__ >= 13
309                 vm_page_replace(page, object, (*mres)->pindex, *mres);
310 #else
311                 vm_page_t mret = vm_page_replace(page, object, (*mres)->pindex);
312                 KASSERT(mret == *mres,
313                     ("invalid page replacement, old=%p, ret=%p", *mres, mret));
314                 vm_page_lock(mret);
315                 vm_page_free(mret);
316                 vm_page_unlock(mret);
317 #endif
318                 *mres = page;
319         }
320
321         page->valid = VM_PAGE_BITS_ALL;
322
323         return VM_PAGER_OK;
324 }
325
326 static struct cdev_pager_ops contigmem_cdev_pager_ops = {
327         .cdev_pg_ctor = contigmem_cdev_pager_ctor,
328         .cdev_pg_dtor = contigmem_cdev_pager_dtor,
329         .cdev_pg_fault = contigmem_cdev_pager_fault,
330 };
331
332 static int
333 contigmem_mmap_single(struct cdev *cdev, vm_ooffset_t *offset, vm_size_t size,
334                 struct vm_object **obj, int nprot)
335 {
336         struct contigmem_vm_handle *vmh;
337         uint64_t buffer_index;
338
339         /*
340          * The buffer index is encoded in the offset.  Divide the offset by
341          *  PAGE_SIZE to get the index of the buffer requested by the user
342          *  app.
343          */
344         buffer_index = *offset / PAGE_SIZE;
345         if (buffer_index >= contigmem_num_buffers)
346                 return EINVAL;
347
348         if (size > contigmem_buffer_size)
349                 return EINVAL;
350
351         vmh = malloc(sizeof(*vmh), M_CONTIGMEM, M_NOWAIT | M_ZERO);
352         if (vmh == NULL)
353                 return ENOMEM;
354         vmh->buffer_index = buffer_index;
355
356         *offset = (vm_ooffset_t)vtophys(contigmem_buffers[buffer_index].addr);
357         *obj = cdev_pager_allocate(vmh, OBJT_DEVICE, &contigmem_cdev_pager_ops,
358                         size, nprot, *offset, curthread->td_ucred);
359
360         return 0;
361 }