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