target/linux/bcm27xx/patches-5.4/950-0732-dma-buf-heaps-Add-system-heap-to-dmabuf-heaps.patch

   1 From 8392cd87592f31737286ea16f11781a234de3564 Mon Sep 17 00:00:00 2001
   2 From: John Stultz <john.stultz@linaro.org>
   3 Date: Tue, 3 Dec 2019 17:26:39 +0000
   4 Subject: [PATCH] dma-buf: heaps: Add system heap to dmabuf heaps
   5
   6 Commit efa04fefebbd724ffda7f49e42d057a7217c45b0 upstream.
   7
   8 This patch adds system heap to the dma-buf heaps framework.
   9
  10 This allows applications to get a page-allocator backed dma-buf
  11 for non-contiguous memory.
  12
  13 This code is an evolution of the Android ION implementation, so
  14 thanks to its original authors and maintainters:
  15   Rebecca Schultz Zavin, Colin Cross, Laura Abbott, and others!
  16
  17 Cc: Laura Abbott <labbott@redhat.com>
  18 Cc: Benjamin Gaignard <benjamin.gaignard@linaro.org>
  19 Cc: Sumit Semwal <sumit.semwal@linaro.org>
  20 Cc: Liam Mark <lmark@codeaurora.org>
  21 Cc: Pratik Patel <pratikp@codeaurora.org>
  22 Cc: Brian Starkey <Brian.Starkey@arm.com>
  23 Cc: Vincent Donnefort <Vincent.Donnefort@arm.com>
  24 Cc: Sudipto Paul <Sudipto.Paul@arm.com>
  25 Cc: Andrew F. Davis <afd@ti.com>
  26 Cc: Christoph Hellwig <hch@infradead.org>
  27 Cc: Chenbo Feng <fengc@google.com>
  28 Cc: Alistair Strachan <astrachan@google.com>
  29 Cc: Hridya Valsaraju <hridya@google.com>
  30 Cc: Sandeep Patil <sspatil@google.com>
  31 Cc: Hillf Danton <hdanton@sina.com>
  32 Cc: Dave Airlie <airlied@gmail.com>
  33 Cc: dri-devel@lists.freedesktop.org
  34 Reviewed-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
  35 Reviewed-by: Brian Starkey <brian.starkey@arm.com>
  36 Acked-by: Sandeep Patil <sspatil@android.com>
  37 Acked-by: Laura Abbott <labbott@redhat.com>
  38 Tested-by: Ayan Kumar Halder <ayan.halder@arm.com>
  39 Signed-off-by: John Stultz <john.stultz@linaro.org>
  40 Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
  41 Link: https://patchwork.freedesktop.org/patch/msgid/20191203172641.66642-4-john.stultz@linaro.org
  42 ---
  43  drivers/dma-buf/Kconfig             |   2 +
  44  drivers/dma-buf/heaps/Kconfig       |   6 ++
  45  drivers/dma-buf/heaps/Makefile      |   1 +
  46  drivers/dma-buf/heaps/system_heap.c | 123 ++++++++++++++++++++++++++++
  47  4 files changed, 132 insertions(+)
  48  create mode 100644 drivers/dma-buf/heaps/Kconfig
  49  create mode 100644 drivers/dma-buf/heaps/system_heap.c
  50
  51 --- a/drivers/dma-buf/Kconfig
  52 +++ b/drivers/dma-buf/Kconfig
  53 @@ -53,4 +53,6 @@ menuconfig DMABUF_HEAPS
  54           allows userspace to allocate dma-bufs that can be shared
  55           between drivers.
  56
  57 +source "drivers/dma-buf/heaps/Kconfig"
  58 +
  59  endmenu
  60 --- /dev/null
  61 +++ b/drivers/dma-buf/heaps/Kconfig
  62 @@ -0,0 +1,6 @@
  63 +config DMABUF_HEAPS_SYSTEM
  64 +       bool "DMA-BUF System Heap"
  65 +       depends on DMABUF_HEAPS
  66 +       help
  67 +         Choose this option to enable the system dmabuf heap. The system heap
  68 +         is backed by pages from the buddy allocator. If in doubt, say Y.
  69 --- a/drivers/dma-buf/heaps/Makefile
  70 +++ b/drivers/dma-buf/heaps/Makefile
  71 @@ -1,2 +1,3 @@
  72  # SPDX-License-Identifier: GPL-2.0
  73  obj-y                                  += heap-helpers.o
  74 +obj-$(CONFIG_DMABUF_HEAPS_SYSTEM)      += system_heap.o
  75 --- /dev/null
  76 +++ b/drivers/dma-buf/heaps/system_heap.c
  77 @@ -0,0 +1,123 @@
  78 +// SPDX-License-Identifier: GPL-2.0
  79 +/*
  80 + * DMABUF System heap exporter
  81 + *
  82 + * Copyright (C) 2011 Google, Inc.
  83 + * Copyright (C) 2019 Linaro Ltd.
  84 + */
  85 +
  86 +#include <linux/dma-buf.h>
  87 +#include <linux/dma-mapping.h>
  88 +#include <linux/dma-heap.h>
  89 +#include <linux/err.h>
  90 +#include <linux/highmem.h>
  91 +#include <linux/mm.h>
  92 +#include <linux/module.h>
  93 +#include <linux/scatterlist.h>
  94 +#include <linux/slab.h>
  95 +#include <linux/sched/signal.h>
  96 +#include <asm/page.h>
  97 +
  98 +#include "heap-helpers.h"
  99 +
 100 +struct dma_heap *sys_heap;
 101 +
 102 +static void system_heap_free(struct heap_helper_buffer *buffer)
 103 +{
 104 +       pgoff_t pg;
 105 +
 106 +       for (pg = 0; pg < buffer->pagecount; pg++)
 107 +               __free_page(buffer->pages[pg]);
 108 +       kfree(buffer->pages);
 109 +       kfree(buffer);
 110 +}
 111 +
 112 +static int system_heap_allocate(struct dma_heap *heap,
 113 +                               unsigned long len,
 114 +                               unsigned long fd_flags,
 115 +                               unsigned long heap_flags)
 116 +{
 117 +       struct heap_helper_buffer *helper_buffer;
 118 +       struct dma_buf *dmabuf;
 119 +       int ret = -ENOMEM;
 120 +       pgoff_t pg;
 121 +
 122 +       helper_buffer = kzalloc(sizeof(*helper_buffer), GFP_KERNEL);
 123 +       if (!helper_buffer)
 124 +               return -ENOMEM;
 125 +
 126 +       init_heap_helper_buffer(helper_buffer, system_heap_free);
 127 +       helper_buffer->heap = heap;
 128 +       helper_buffer->size = len;
 129 +
 130 +       helper_buffer->pagecount = len / PAGE_SIZE;
 131 +       helper_buffer->pages = kmalloc_array(helper_buffer->pagecount,
 132 +                                            sizeof(*helper_buffer->pages),
 133 +                                            GFP_KERNEL);
 134 +       if (!helper_buffer->pages) {
 135 +               ret = -ENOMEM;
 136 +               goto err0;
 137 +       }
 138 +
 139 +       for (pg = 0; pg < helper_buffer->pagecount; pg++) {
 140 +               /*
 141 +                * Avoid trying to allocate memory if the process
 142 +                * has been killed by by SIGKILL
 143 +                */
 144 +               if (fatal_signal_pending(current))
 145 +                       goto err1;
 146 +
 147 +               helper_buffer->pages[pg] = alloc_page(GFP_KERNEL | __GFP_ZERO);
 148 +               if (!helper_buffer->pages[pg])
 149 +                       goto err1;
 150 +       }
 151 +
 152 +       /* create the dmabuf */
 153 +       dmabuf = heap_helper_export_dmabuf(helper_buffer, fd_flags);
 154 +       if (IS_ERR(dmabuf)) {
 155 +               ret = PTR_ERR(dmabuf);
 156 +               goto err1;
 157 +       }
 158 +
 159 +       helper_buffer->dmabuf = dmabuf;
 160 +
 161 +       ret = dma_buf_fd(dmabuf, fd_flags);
 162 +       if (ret < 0) {
 163 +               dma_buf_put(dmabuf);
 164 +               /* just return, as put will call release and that will free */
 165 +               return ret;
 166 +       }
 167 +
 168 +       return ret;
 169 +
 170 +err1:
 171 +       while (pg > 0)
 172 +               __free_page(helper_buffer->pages[--pg]);
 173 +       kfree(helper_buffer->pages);
 174 +err0:
 175 +       kfree(helper_buffer);
 176 +
 177 +       return ret;
 178 +}
 179 +
 180 +static const struct dma_heap_ops system_heap_ops = {
 181 +       .allocate = system_heap_allocate,
 182 +};
 183 +
 184 +static int system_heap_create(void)
 185 +{
 186 +       struct dma_heap_export_info exp_info;
 187 +       int ret = 0;
 188 +
 189 +       exp_info.name = "system_heap";
 190 +       exp_info.ops = &system_heap_ops;
 191 +       exp_info.priv = NULL;
 192 +
 193 +       sys_heap = dma_heap_add(&exp_info);
 194 +       if (IS_ERR(sys_heap))
 195 +               ret = PTR_ERR(sys_heap);
 196 +
 197 +       return ret;
 198 +}
 199 +module_init(system_heap_create);
 200 +MODULE_LICENSE("GPL v2");