target/linux/bcm27xx/patches-5.4/950-0733-dma-buf-heaps-Add-heap-helpers.patch

   1 From adde2d6532428cdcaeb60081abb299ce6e5aa76b Mon Sep 17 00:00:00 2001
   2 From: John Stultz <john.stultz@linaro.org>
   3 Date: Tue, 3 Dec 2019 17:26:38 +0000
   4 Subject: [PATCH] dma-buf: heaps: Add heap helpers
   5
   6 Commit 5248eb12fea890a03b4cdc3ef546d6319d4d9b73 upstream.
   7
   8 Add generic helper dmabuf ops for dma heaps, so we can reduce
   9 the amount of duplicative code for the exported dmabufs.
  10
  11 This code is an evolution of the Android ION implementation, so
  12 thanks to its original authors and maintainters:
  13   Rebecca Schultz Zavin, Colin Cross, Laura Abbott, and others!
  14
  15 Cc: Laura Abbott <labbott@redhat.com>
  16 Cc: Benjamin Gaignard <benjamin.gaignard@linaro.org>
  17 Cc: Sumit Semwal <sumit.semwal@linaro.org>
  18 Cc: Liam Mark <lmark@codeaurora.org>
  19 Cc: Pratik Patel <pratikp@codeaurora.org>
  20 Cc: Brian Starkey <Brian.Starkey@arm.com>
  21 Cc: Vincent Donnefort <Vincent.Donnefort@arm.com>
  22 Cc: Sudipto Paul <Sudipto.Paul@arm.com>
  23 Cc: Andrew F. Davis <afd@ti.com>
  24 Cc: Christoph Hellwig <hch@infradead.org>
  25 Cc: Chenbo Feng <fengc@google.com>
  26 Cc: Alistair Strachan <astrachan@google.com>
  27 Cc: Hridya Valsaraju <hridya@google.com>
  28 Cc: Sandeep Patil <sspatil@google.com>
  29 Cc: Hillf Danton <hdanton@sina.com>
  30 Cc: Dave Airlie <airlied@gmail.com>
  31 Cc: dri-devel@lists.freedesktop.org
  32 Reviewed-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
  33 Reviewed-by: Brian Starkey <brian.starkey@arm.com>
  34 Acked-by: Sandeep Patil <sspatil@android.com>
  35 Acked-by: Laura Abbott <labbott@redhat.com>
  36 Tested-by: Ayan Kumar Halder <ayan.halder@arm.com>
  37 Signed-off-by: John Stultz <john.stultz@linaro.org>
  38 Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
  39 Link: https://patchwork.freedesktop.org/patch/msgid/20191203172641.66642-3-john.stultz@linaro.org
  40 ---
  41  drivers/dma-buf/Makefile             |   1 +
  42  drivers/dma-buf/heaps/Makefile       |   2 +
  43  drivers/dma-buf/heaps/heap-helpers.c | 271 +++++++++++++++++++++++++++
  44  drivers/dma-buf/heaps/heap-helpers.h |  53 ++++++
  45  4 files changed, 327 insertions(+)
  46  create mode 100644 drivers/dma-buf/heaps/Makefile
  47  create mode 100644 drivers/dma-buf/heaps/heap-helpers.c
  48  create mode 100644 drivers/dma-buf/heaps/heap-helpers.h
  49
  50 --- a/drivers/dma-buf/Makefile
  51 +++ b/drivers/dma-buf/Makefile
  52 @@ -4,6 +4,7 @@ obj-$(CONFIG_DMA_SHARED_BUFFER) := dma-s
  53  dma-buf-objs-y := dma-buf.o dma-fence.o dma-fence-array.o dma-fence-chain.o \
  54                   dma-resv.o seqno-fence.o
  55  obj-$(CONFIG_DMABUF_HEAPS)     += dma-heap.o
  56 +obj-$(CONFIG_DMABUF_HEAPS)     += heaps/
  57  dma-buf-objs-$(CONFIG_SYNC_FILE)       += sync_file.o
  58  dma-buf-objs-$(CONFIG_SW_SYNC)         += sw_sync.o sync_debug.o
  59  dma-buf-objs-$(CONFIG_UDMABUF)         += udmabuf.o
  60 --- /dev/null
  61 +++ b/drivers/dma-buf/heaps/Makefile
  62 @@ -0,0 +1,2 @@
  63 +# SPDX-License-Identifier: GPL-2.0
  64 +obj-y                                  += heap-helpers.o
  65 --- /dev/null
  66 +++ b/drivers/dma-buf/heaps/heap-helpers.c
  67 @@ -0,0 +1,271 @@
  68 +// SPDX-License-Identifier: GPL-2.0
  69 +#include <linux/device.h>
  70 +#include <linux/dma-buf.h>
  71 +#include <linux/err.h>
  72 +#include <linux/highmem.h>
  73 +#include <linux/idr.h>
  74 +#include <linux/list.h>
  75 +#include <linux/slab.h>
  76 +#include <linux/uaccess.h>
  77 +#include <linux/vmalloc.h>
  78 +#include <uapi/linux/dma-heap.h>
  79 +
  80 +#include "heap-helpers.h"
  81 +
  82 +void init_heap_helper_buffer(struct heap_helper_buffer *buffer,
  83 +                            void (*free)(struct heap_helper_buffer *))
  84 +{
  85 +       buffer->priv_virt = NULL;
  86 +       mutex_init(&buffer->lock);
  87 +       buffer->vmap_cnt = 0;
  88 +       buffer->vaddr = NULL;
  89 +       buffer->pagecount = 0;
  90 +       buffer->pages = NULL;
  91 +       INIT_LIST_HEAD(&buffer->attachments);
  92 +       buffer->free = free;
  93 +}
  94 +
  95 +struct dma_buf *heap_helper_export_dmabuf(struct heap_helper_buffer *buffer,
  96 +                                         int fd_flags)
  97 +{
  98 +       DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
  99 +
 100 +       exp_info.ops = &heap_helper_ops;
 101 +       exp_info.size = buffer->size;
 102 +       exp_info.flags = fd_flags;
 103 +       exp_info.priv = buffer;
 104 +
 105 +       return dma_buf_export(&exp_info);
 106 +}
 107 +
 108 +static void *dma_heap_map_kernel(struct heap_helper_buffer *buffer)
 109 +{
 110 +       void *vaddr;
 111 +
 112 +       vaddr = vmap(buffer->pages, buffer->pagecount, VM_MAP, PAGE_KERNEL);
 113 +       if (!vaddr)
 114 +               return ERR_PTR(-ENOMEM);
 115 +
 116 +       return vaddr;
 117 +}
 118 +
 119 +static void dma_heap_buffer_destroy(struct heap_helper_buffer *buffer)
 120 +{
 121 +       if (buffer->vmap_cnt > 0) {
 122 +               WARN(1, "%s: buffer still mapped in the kernel\n", __func__);
 123 +               vunmap(buffer->vaddr);
 124 +       }
 125 +
 126 +       buffer->free(buffer);
 127 +}
 128 +
 129 +static void *dma_heap_buffer_vmap_get(struct heap_helper_buffer *buffer)
 130 +{
 131 +       void *vaddr;
 132 +
 133 +       if (buffer->vmap_cnt) {
 134 +               buffer->vmap_cnt++;
 135 +               return buffer->vaddr;
 136 +       }
 137 +       vaddr = dma_heap_map_kernel(buffer);
 138 +       if (IS_ERR(vaddr))
 139 +               return vaddr;
 140 +       buffer->vaddr = vaddr;
 141 +       buffer->vmap_cnt++;
 142 +       return vaddr;
 143 +}
 144 +
 145 +static void dma_heap_buffer_vmap_put(struct heap_helper_buffer *buffer)
 146 +{
 147 +       if (!--buffer->vmap_cnt) {
 148 +               vunmap(buffer->vaddr);
 149 +               buffer->vaddr = NULL;
 150 +       }
 151 +}
 152 +
 153 +struct dma_heaps_attachment {
 154 +       struct device *dev;
 155 +       struct sg_table table;
 156 +       struct list_head list;
 157 +};
 158 +
 159 +static int dma_heap_attach(struct dma_buf *dmabuf,
 160 +                          struct dma_buf_attachment *attachment)
 161 +{
 162 +       struct dma_heaps_attachment *a;
 163 +       struct heap_helper_buffer *buffer = dmabuf->priv;
 164 +       int ret;
 165 +
 166 +       a = kzalloc(sizeof(*a), GFP_KERNEL);
 167 +       if (!a)
 168 +               return -ENOMEM;
 169 +
 170 +       ret = sg_alloc_table_from_pages(&a->table, buffer->pages,
 171 +                                       buffer->pagecount, 0,
 172 +                                       buffer->pagecount << PAGE_SHIFT,
 173 +                                       GFP_KERNEL);
 174 +       if (ret) {
 175 +               kfree(a);
 176 +               return ret;
 177 +       }
 178 +
 179 +       a->dev = attachment->dev;
 180 +       INIT_LIST_HEAD(&a->list);
 181 +
 182 +       attachment->priv = a;
 183 +
 184 +       mutex_lock(&buffer->lock);
 185 +       list_add(&a->list, &buffer->attachments);
 186 +       mutex_unlock(&buffer->lock);
 187 +
 188 +       return 0;
 189 +}
 190 +
 191 +static void dma_heap_detach(struct dma_buf *dmabuf,
 192 +                           struct dma_buf_attachment *attachment)
 193 +{
 194 +       struct dma_heaps_attachment *a = attachment->priv;
 195 +       struct heap_helper_buffer *buffer = dmabuf->priv;
 196 +
 197 +       mutex_lock(&buffer->lock);
 198 +       list_del(&a->list);
 199 +       mutex_unlock(&buffer->lock);
 200 +
 201 +       sg_free_table(&a->table);
 202 +       kfree(a);
 203 +}
 204 +
 205 +static
 206 +struct sg_table *dma_heap_map_dma_buf(struct dma_buf_attachment *attachment,
 207 +                                     enum dma_data_direction direction)
 208 +{
 209 +       struct dma_heaps_attachment *a = attachment->priv;
 210 +       struct sg_table *table;
 211 +
 212 +       table = &a->table;
 213 +
 214 +       if (!dma_map_sg(attachment->dev, table->sgl, table->nents,
 215 +                       direction))
 216 +               table = ERR_PTR(-ENOMEM);
 217 +       return table;
 218 +}
 219 +
 220 +static void dma_heap_unmap_dma_buf(struct dma_buf_attachment *attachment,
 221 +                                  struct sg_table *table,
 222 +                                  enum dma_data_direction direction)
 223 +{
 224 +       dma_unmap_sg(attachment->dev, table->sgl, table->nents, direction);
 225 +}
 226 +
 227 +static vm_fault_t dma_heap_vm_fault(struct vm_fault *vmf)
 228 +{
 229 +       struct vm_area_struct *vma = vmf->vma;
 230 +       struct heap_helper_buffer *buffer = vma->vm_private_data;
 231 +
 232 +       if (vmf->pgoff > buffer->pagecount)
 233 +               return VM_FAULT_SIGBUS;
 234 +
 235 +       vmf->page = buffer->pages[vmf->pgoff];
 236 +       get_page(vmf->page);
 237 +
 238 +       return 0;
 239 +}
 240 +
 241 +static const struct vm_operations_struct dma_heap_vm_ops = {
 242 +       .fault = dma_heap_vm_fault,
 243 +};
 244 +
 245 +static int dma_heap_mmap(struct dma_buf *dmabuf, struct vm_area_struct *vma)
 246 +{
 247 +       struct heap_helper_buffer *buffer = dmabuf->priv;
 248 +
 249 +       if ((vma->vm_flags & (VM_SHARED | VM_MAYSHARE)) == 0)
 250 +               return -EINVAL;
 251 +
 252 +       vma->vm_ops = &dma_heap_vm_ops;
 253 +       vma->vm_private_data = buffer;
 254 +
 255 +       return 0;
 256 +}
 257 +
 258 +static void dma_heap_dma_buf_release(struct dma_buf *dmabuf)
 259 +{
 260 +       struct heap_helper_buffer *buffer = dmabuf->priv;
 261 +
 262 +       dma_heap_buffer_destroy(buffer);
 263 +}
 264 +
 265 +static int dma_heap_dma_buf_begin_cpu_access(struct dma_buf *dmabuf,
 266 +                                            enum dma_data_direction direction)
 267 +{
 268 +       struct heap_helper_buffer *buffer = dmabuf->priv;
 269 +       struct dma_heaps_attachment *a;
 270 +       int ret = 0;
 271 +
 272 +       mutex_lock(&buffer->lock);
 273 +
 274 +       if (buffer->vmap_cnt)
 275 +               invalidate_kernel_vmap_range(buffer->vaddr, buffer->size);
 276 +
 277 +       list_for_each_entry(a, &buffer->attachments, list) {
 278 +               dma_sync_sg_for_cpu(a->dev, a->table.sgl, a->table.nents,
 279 +                                   direction);
 280 +       }
 281 +       mutex_unlock(&buffer->lock);
 282 +
 283 +       return ret;
 284 +}
 285 +
 286 +static int dma_heap_dma_buf_end_cpu_access(struct dma_buf *dmabuf,
 287 +                                          enum dma_data_direction direction)
 288 +{
 289 +       struct heap_helper_buffer *buffer = dmabuf->priv;
 290 +       struct dma_heaps_attachment *a;
 291 +
 292 +       mutex_lock(&buffer->lock);
 293 +
 294 +       if (buffer->vmap_cnt)
 295 +               flush_kernel_vmap_range(buffer->vaddr, buffer->size);
 296 +
 297 +       list_for_each_entry(a, &buffer->attachments, list) {
 298 +               dma_sync_sg_for_device(a->dev, a->table.sgl, a->table.nents,
 299 +                                      direction);
 300 +       }
 301 +       mutex_unlock(&buffer->lock);
 302 +
 303 +       return 0;
 304 +}
 305 +
 306 +static void *dma_heap_dma_buf_vmap(struct dma_buf *dmabuf)
 307 +{
 308 +       struct heap_helper_buffer *buffer = dmabuf->priv;
 309 +       void *vaddr;
 310 +
 311 +       mutex_lock(&buffer->lock);
 312 +       vaddr = dma_heap_buffer_vmap_get(buffer);
 313 +       mutex_unlock(&buffer->lock);
 314 +
 315 +       return vaddr;
 316 +}
 317 +
 318 +static void dma_heap_dma_buf_vunmap(struct dma_buf *dmabuf, void *vaddr)
 319 +{
 320 +       struct heap_helper_buffer *buffer = dmabuf->priv;
 321 +
 322 +       mutex_lock(&buffer->lock);
 323 +       dma_heap_buffer_vmap_put(buffer);
 324 +       mutex_unlock(&buffer->lock);
 325 +}
 326 +
 327 +const struct dma_buf_ops heap_helper_ops = {
 328 +       .map_dma_buf = dma_heap_map_dma_buf,
 329 +       .unmap_dma_buf = dma_heap_unmap_dma_buf,
 330 +       .mmap = dma_heap_mmap,
 331 +       .release = dma_heap_dma_buf_release,
 332 +       .attach = dma_heap_attach,
 333 +       .detach = dma_heap_detach,
 334 +       .begin_cpu_access = dma_heap_dma_buf_begin_cpu_access,
 335 +       .end_cpu_access = dma_heap_dma_buf_end_cpu_access,
 336 +       .vmap = dma_heap_dma_buf_vmap,
 337 +       .vunmap = dma_heap_dma_buf_vunmap,
 338 +};
 339 --- /dev/null
 340 +++ b/drivers/dma-buf/heaps/heap-helpers.h
 341 @@ -0,0 +1,53 @@
 342 +/* SPDX-License-Identifier: GPL-2.0 */
 343 +/*
 344 + * DMABUF Heaps helper code
 345 + *
 346 + * Copyright (C) 2011 Google, Inc.
 347 + * Copyright (C) 2019 Linaro Ltd.
 348 + */
 349 +
 350 +#ifndef _HEAP_HELPERS_H
 351 +#define _HEAP_HELPERS_H
 352 +
 353 +#include <linux/dma-heap.h>
 354 +#include <linux/list.h>
 355 +
 356 +/**
 357 + * struct heap_helper_buffer - helper buffer metadata
 358 + * @heap:              back pointer to the heap the buffer came from
 359 + * @dmabuf:            backing dma-buf for this buffer
 360 + * @size:              size of the buffer
 361 + * @priv_virt          pointer to heap specific private value
 362 + * @lock               mutext to protect the data in this structure
 363 + * @vmap_cnt           count of vmap references on the buffer
 364 + * @vaddr              vmap'ed virtual address
 365 + * @pagecount          number of pages in the buffer
 366 + * @pages              list of page pointers
 367 + * @attachments                list of device attachments
 368 + *
 369 + * @free               heap callback to free the buffer
 370 + */
 371 +struct heap_helper_buffer {
 372 +       struct dma_heap *heap;
 373 +       struct dma_buf *dmabuf;
 374 +       size_t size;
 375 +
 376 +       void *priv_virt;
 377 +       struct mutex lock;
 378 +       int vmap_cnt;
 379 +       void *vaddr;
 380 +       pgoff_t pagecount;
 381 +       struct page **pages;
 382 +       struct list_head attachments;
 383 +
 384 +       void (*free)(struct heap_helper_buffer *buffer);
 385 +};
 386 +
 387 +void init_heap_helper_buffer(struct heap_helper_buffer *buffer,
 388 +                            void (*free)(struct heap_helper_buffer *));
 389 +
 390 +struct dma_buf *heap_helper_export_dmabuf(struct heap_helper_buffer *buffer,
 391 +                                         int fd_flags);
 392 +
 393 +extern const struct dma_buf_ops heap_helper_ops;
 394 +#endif /* _HEAP_HELPERS_H */