1 /* 2 * videobuf2-vmalloc.c - vmalloc memory allocator for videobuf2 3 * 4 * Copyright (C) 2010 Samsung Electronics 5 * 6 * Author: Pawel Osciak <pawel@osciak.com> 7 * 8 * This program is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License as published by 10 * the Free Software Foundation. 11 */ 12 13 #include <linux/dma-resv.h> 14 #include <linux/io.h> 15 #include <linux/module.h> 16 #include <linux/mm.h> 17 #include <linux/refcount.h> 18 #include <linux/sched.h> 19 #include <linux/slab.h> 20 #include <linux/vmalloc.h> 21 22 #include <media/videobuf2-v4l2.h> 23 #include <media/videobuf2-vmalloc.h> 24 #include <media/videobuf2-memops.h> 25 26 struct vb2_vmalloc_buf { 27 void *vaddr; 28 struct frame_vector *vec; 29 enum dma_data_direction dma_dir; 30 unsigned long size; 31 refcount_t refcount; 32 struct vb2_vmarea_handler handler; 33 struct dma_buf *dbuf; 34 }; 35 36 static void vb2_vmalloc_put(void *buf_priv); 37 38 static void *vb2_vmalloc_alloc(struct vb2_buffer *vb, struct device *dev, 39 unsigned long size) 40 { 41 struct vb2_vmalloc_buf *buf; 42 43 buf = kzalloc(sizeof(*buf), GFP_KERNEL | vb->vb2_queue->gfp_flags); 44 if (!buf) 45 return ERR_PTR(-ENOMEM); 46 47 buf->size = size; 48 buf->vaddr = vmalloc_user(buf->size); 49 if (!buf->vaddr) { 50 pr_debug("vmalloc of size %ld failed\n", buf->size); 51 kfree(buf); 52 return ERR_PTR(-ENOMEM); 53 } 54 55 buf->dma_dir = vb->vb2_queue->dma_dir; 56 buf->handler.refcount = &buf->refcount; 57 buf->handler.put = vb2_vmalloc_put; 58 buf->handler.arg = buf; 59 60 refcount_set(&buf->refcount, 1); 61 return buf; 62 } 63 64 static void vb2_vmalloc_put(void *buf_priv) 65 { 66 struct vb2_vmalloc_buf *buf = buf_priv; 67 68 if (refcount_dec_and_test(&buf->refcount)) { 69 vfree(buf->vaddr); 70 kfree(buf); 71 } 72 } 73 74 static void *vb2_vmalloc_get_userptr(struct vb2_buffer *vb, struct device *dev, 75 unsigned long vaddr, unsigned long size) 76 { 77 struct vb2_vmalloc_buf *buf; 78 struct frame_vector *vec; 79 int n_pages, offset, i; 80 int ret = -ENOMEM; 81 82 buf = kzalloc(sizeof(*buf), GFP_KERNEL); 83 if (!buf) 84 return ERR_PTR(-ENOMEM); 85 86 buf->dma_dir = vb->vb2_queue->dma_dir; 87 offset = vaddr & ~PAGE_MASK; 88 buf->size = size; 89 vec = vb2_create_framevec(vaddr, size, 90 buf->dma_dir == DMA_FROM_DEVICE || 91 buf->dma_dir == DMA_BIDIRECTIONAL); 92 if (IS_ERR(vec)) { 93 ret = PTR_ERR(vec); 94 goto fail_pfnvec_create; 95 } 96 buf->vec = vec; 97 n_pages = frame_vector_count(vec); 98 if (frame_vector_to_pages(vec) < 0) { 99 unsigned long *nums = frame_vector_pfns(vec); 100 101 /* 102 * We cannot get page pointers for these pfns. Check memory is 103 * physically contiguous and use direct mapping. 104 */ 105 for (i = 1; i < n_pages; i++) 106 if (nums[i-1] + 1 != nums[i]) 107 goto fail_map; 108 buf->vaddr = (__force void *) 109 ioremap(__pfn_to_phys(nums[0]), size + offset); 110 } else { 111 buf->vaddr = vm_map_ram(frame_vector_pages(vec), n_pages, -1); 112 } 113 114 if (!buf->vaddr) 115 goto fail_map; 116 buf->vaddr += offset; 117 return buf; 118 119 fail_map: 120 vb2_destroy_framevec(vec); 121 fail_pfnvec_create: 122 kfree(buf); 123 124 return ERR_PTR(ret); 125 } 126 127 static void vb2_vmalloc_put_userptr(void *buf_priv) 128 { 129 struct vb2_vmalloc_buf *buf = buf_priv; 130 unsigned long vaddr = (unsigned long)buf->vaddr & PAGE_MASK; 131 unsigned int i; 132 struct page **pages; 133 unsigned int n_pages; 134 135 if (!buf->vec->is_pfns) { 136 n_pages = frame_vector_count(buf->vec); 137 pages = frame_vector_pages(buf->vec); 138 if (vaddr) 139 vm_unmap_ram((void *)vaddr, n_pages); 140 if (buf->dma_dir == DMA_FROM_DEVICE || 141 buf->dma_dir == DMA_BIDIRECTIONAL) 142 for (i = 0; i < n_pages; i++) 143 set_page_dirty_lock(pages[i]); 144 } else { 145 iounmap((__force void __iomem *)buf->vaddr); 146 } 147 vb2_destroy_framevec(buf->vec); 148 kfree(buf); 149 } 150 151 static void *vb2_vmalloc_vaddr(struct vb2_buffer *vb, void *buf_priv) 152 { 153 struct vb2_vmalloc_buf *buf = buf_priv; 154 155 if (!buf->vaddr) { 156 pr_err("Address of an unallocated plane requested or cannot map user pointer\n"); 157 return NULL; 158 } 159 160 return buf->vaddr; 161 } 162 163 static unsigned int vb2_vmalloc_num_users(void *buf_priv) 164 { 165 struct vb2_vmalloc_buf *buf = buf_priv; 166 return refcount_read(&buf->refcount); 167 } 168 169 static int vb2_vmalloc_mmap(void *buf_priv, struct vm_area_struct *vma) 170 { 171 struct vb2_vmalloc_buf *buf = buf_priv; 172 int ret; 173 174 if (!buf) { 175 pr_err("No memory to map\n"); 176 return -EINVAL; 177 } 178 179 ret = remap_vmalloc_range(vma, buf->vaddr, 0); 180 if (ret) { 181 pr_err("Remapping vmalloc memory, error: %d\n", ret); 182 return ret; 183 } 184 185 /* 186 * Make sure that vm_areas for 2 buffers won't be merged together 187 */ 188 vm_flags_set(vma, VM_DONTEXPAND); 189 190 /* 191 * Use common vm_area operations to track buffer refcount. 192 */ 193 vma->vm_private_data = &buf->handler; 194 vma->vm_ops = &vb2_common_vm_ops; 195 196 vma->vm_ops->open(vma); 197 198 return 0; 199 } 200 201 #ifdef CONFIG_HAS_DMA 202 /*********************************************/ 203 /* DMABUF ops for exporters */ 204 /*********************************************/ 205 206 struct vb2_vmalloc_attachment { 207 struct sg_table sgt; 208 enum dma_data_direction dma_dir; 209 }; 210 211 static int vb2_vmalloc_dmabuf_ops_attach(struct dma_buf *dbuf, 212 struct dma_buf_attachment *dbuf_attach) 213 { 214 struct vb2_vmalloc_attachment *attach; 215 struct vb2_vmalloc_buf *buf = dbuf->priv; 216 int num_pages = PAGE_ALIGN(buf->size) / PAGE_SIZE; 217 struct sg_table *sgt; 218 struct scatterlist *sg; 219 void *vaddr = buf->vaddr; 220 int ret; 221 int i; 222 223 attach = kzalloc(sizeof(*attach), GFP_KERNEL); 224 if (!attach) 225 return -ENOMEM; 226 227 sgt = &attach->sgt; 228 ret = sg_alloc_table(sgt, num_pages, GFP_KERNEL); 229 if (ret) { 230 kfree(attach); 231 return ret; 232 } 233 for_each_sgtable_sg(sgt, sg, i) { 234 struct page *page = vmalloc_to_page(vaddr); 235 236 if (!page) { 237 sg_free_table(sgt); 238 kfree(attach); 239 return -ENOMEM; 240 } 241 sg_set_page(sg, page, PAGE_SIZE, 0); 242 vaddr += PAGE_SIZE; 243 } 244 245 attach->dma_dir = DMA_NONE; 246 dbuf_attach->priv = attach; 247 return 0; 248 } 249 250 static void vb2_vmalloc_dmabuf_ops_detach(struct dma_buf *dbuf, 251 struct dma_buf_attachment *db_attach) 252 { 253 struct vb2_vmalloc_attachment *attach = db_attach->priv; 254 struct sg_table *sgt; 255 256 if (!attach) 257 return; 258 259 sgt = &attach->sgt; 260 261 /* release the scatterlist cache */ 262 if (attach->dma_dir != DMA_NONE) 263 dma_unmap_sgtable(db_attach->dev, sgt, attach->dma_dir, 0); 264 sg_free_table(sgt); 265 kfree(attach); 266 db_attach->priv = NULL; 267 } 268 269 static struct sg_table *vb2_vmalloc_dmabuf_ops_map( 270 struct dma_buf_attachment *db_attach, enum dma_data_direction dma_dir) 271 { 272 struct vb2_vmalloc_attachment *attach = db_attach->priv; 273 struct sg_table *sgt; 274 275 sgt = &attach->sgt; 276 /* return previously mapped sg table */ 277 if (attach->dma_dir == dma_dir) 278 return sgt; 279 280 /* release any previous cache */ 281 if (attach->dma_dir != DMA_NONE) { 282 dma_unmap_sgtable(db_attach->dev, sgt, attach->dma_dir, 0); 283 attach->dma_dir = DMA_NONE; 284 } 285 286 /* mapping to the client with new direction */ 287 if (dma_map_sgtable(db_attach->dev, sgt, dma_dir, 0)) { 288 pr_err("failed to map scatterlist\n"); 289 return ERR_PTR(-EIO); 290 } 291 292 attach->dma_dir = dma_dir; 293 294 return sgt; 295 } 296 297 static void vb2_vmalloc_dmabuf_ops_unmap(struct dma_buf_attachment *db_attach, 298 struct sg_table *sgt, enum dma_data_direction dma_dir) 299 { 300 /* nothing to be done here */ 301 } 302 303 static void vb2_vmalloc_dmabuf_ops_release(struct dma_buf *dbuf) 304 { 305 /* drop reference obtained in vb2_vmalloc_get_dmabuf */ 306 vb2_vmalloc_put(dbuf->priv); 307 } 308 309 static int vb2_vmalloc_dmabuf_ops_vmap(struct dma_buf *dbuf, 310 struct iosys_map *map) 311 { 312 struct vb2_vmalloc_buf *buf = dbuf->priv; 313 314 iosys_map_set_vaddr(map, buf->vaddr); 315 316 return 0; 317 } 318 319 static int vb2_vmalloc_dmabuf_ops_mmap(struct dma_buf *dbuf, 320 struct vm_area_struct *vma) 321 { 322 dma_resv_assert_held(dbuf->resv); 323 324 return vb2_vmalloc_mmap(dbuf->priv, vma); 325 } 326 327 static const struct dma_buf_ops vb2_vmalloc_dmabuf_ops = { 328 .attach = vb2_vmalloc_dmabuf_ops_attach, 329 .detach = vb2_vmalloc_dmabuf_ops_detach, 330 .map_dma_buf = vb2_vmalloc_dmabuf_ops_map, 331 .unmap_dma_buf = vb2_vmalloc_dmabuf_ops_unmap, 332 .vmap = vb2_vmalloc_dmabuf_ops_vmap, 333 .mmap = vb2_vmalloc_dmabuf_ops_mmap, 334 .release = vb2_vmalloc_dmabuf_ops_release, 335 }; 336 337 static struct dma_buf *vb2_vmalloc_get_dmabuf(struct vb2_buffer *vb, 338 void *buf_priv, 339 unsigned long flags) 340 { 341 struct vb2_vmalloc_buf *buf = buf_priv; 342 struct dma_buf *dbuf; 343 DEFINE_DMA_BUF_EXPORT_INFO(exp_info); 344 345 exp_info.ops = &vb2_vmalloc_dmabuf_ops; 346 exp_info.size = buf->size; 347 exp_info.flags = flags; 348 exp_info.priv = buf; 349 350 if (WARN_ON(!buf->vaddr)) 351 return NULL; 352 353 dbuf = dma_buf_export(&exp_info); 354 if (IS_ERR(dbuf)) 355 return NULL; 356 357 /* dmabuf keeps reference to vb2 buffer */ 358 refcount_inc(&buf->refcount); 359 360 return dbuf; 361 } 362 #endif /* CONFIG_HAS_DMA */ 363 364 365 /*********************************************/ 366 /* callbacks for DMABUF buffers */ 367 /*********************************************/ 368 369 static int vb2_vmalloc_map_dmabuf(void *mem_priv) 370 { 371 struct vb2_vmalloc_buf *buf = mem_priv; 372 struct iosys_map map; 373 int ret; 374 375 ret = dma_buf_vmap_unlocked(buf->dbuf, &map); 376 if (ret) 377 return -EFAULT; 378 buf->vaddr = map.vaddr; 379 380 return 0; 381 } 382 383 static void vb2_vmalloc_unmap_dmabuf(void *mem_priv) 384 { 385 struct vb2_vmalloc_buf *buf = mem_priv; 386 struct iosys_map map = IOSYS_MAP_INIT_VADDR(buf->vaddr); 387 388 dma_buf_vunmap_unlocked(buf->dbuf, &map); 389 buf->vaddr = NULL; 390 } 391 392 static void vb2_vmalloc_detach_dmabuf(void *mem_priv) 393 { 394 struct vb2_vmalloc_buf *buf = mem_priv; 395 struct iosys_map map = IOSYS_MAP_INIT_VADDR(buf->vaddr); 396 397 if (buf->vaddr) 398 dma_buf_vunmap_unlocked(buf->dbuf, &map); 399 400 kfree(buf); 401 } 402 403 static void *vb2_vmalloc_attach_dmabuf(struct vb2_buffer *vb, 404 struct device *dev, 405 struct dma_buf *dbuf, 406 unsigned long size) 407 { 408 struct vb2_vmalloc_buf *buf; 409 410 if (dbuf->size < size) 411 return ERR_PTR(-EFAULT); 412 413 buf = kzalloc(sizeof(*buf), GFP_KERNEL); 414 if (!buf) 415 return ERR_PTR(-ENOMEM); 416 417 buf->dbuf = dbuf; 418 buf->dma_dir = vb->vb2_queue->dma_dir; 419 buf->size = size; 420 421 return buf; 422 } 423 424 425 const struct vb2_mem_ops vb2_vmalloc_memops = { 426 .alloc = vb2_vmalloc_alloc, 427 .put = vb2_vmalloc_put, 428 .get_userptr = vb2_vmalloc_get_userptr, 429 .put_userptr = vb2_vmalloc_put_userptr, 430 #ifdef CONFIG_HAS_DMA 431 .get_dmabuf = vb2_vmalloc_get_dmabuf, 432 #endif 433 .map_dmabuf = vb2_vmalloc_map_dmabuf, 434 .unmap_dmabuf = vb2_vmalloc_unmap_dmabuf, 435 .attach_dmabuf = vb2_vmalloc_attach_dmabuf, 436 .detach_dmabuf = vb2_vmalloc_detach_dmabuf, 437 .vaddr = vb2_vmalloc_vaddr, 438 .mmap = vb2_vmalloc_mmap, 439 .num_users = vb2_vmalloc_num_users, 440 }; 441 EXPORT_SYMBOL_GPL(vb2_vmalloc_memops); 442 443 MODULE_DESCRIPTION("vmalloc memory handling routines for videobuf2"); 444 MODULE_AUTHOR("Pawel Osciak <pawel@osciak.com>"); 445 MODULE_LICENSE("GPL"); 446 MODULE_IMPORT_NS(DMA_BUF); 447