gpu: nvgpu: Move dma_buf usage from mm_gk20a.c

Move most of the dma_buf usage present in the mm_gk20a.c code
out to Linux specific code and some commom/mm code. There's
two primary groups of code:

  1. dma_buf priv field code (for holding comptag data)
  2. Comptag usage that relies on dma_buf pointers

For (1) the dma_buf code was simply moved to common/linux/dmabuf.c
since most of this code is clearly Linux specific.

The comptag code was a bit more complicated since there is two
parts to the comptag code. Firstly there's the code that manages
the comptag memory. This is essentially a simple allocator. This
was moved to common/mm/comptags.c since it can be shared across
all chips. The second set of code is moved to
common/linux/comptags.c since it is the interface between dma_bufs
and the comptag memory.

Two other fixes were done as well:

 - Add struct gk20a to the comptag allocator init so that
   the proper nvgpu_vzalloc() function could be used.
 - Add necessary includes to common/linux/vm_priv.h.

JIRA NVGPU-30
JIRA NVGPU-138

Change-Id: I96c57f2763e5ebe18a2f2ee4b33e0e1a2597848c
Signed-off-by: Alex Waterman <alexw@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/1566628
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>

1 files changed, 95 insertions, 0 deletions

diff --git a/drivers/gpu/nvgpu/common/mm/comptags.c b/drivers/gpu/nvgpu/common/mm/comptags.c
new file mode 100644
index 00000000..01ab646a
--- /dev/null
+++ b/drivers/gpu/nvgpu/common/mm/comptags.c
@@ -0,0 +1,95 @@
+/*
+ * Copyright (c) 2017, NVIDIA CORPORATION.  All rights reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ */
+
+#include <nvgpu/bitops.h>
+#include <nvgpu/comptags.h>
+
+#include "gk20a/gk20a.h"
+
+int gk20a_comptaglines_alloc(struct gk20a_comptag_allocator *allocator,
+                             u32 *offset, u32 len)
+{
+        unsigned long addr;
+        int err = 0;
+
+        nvgpu_mutex_acquire(&allocator->lock);
+        addr = bitmap_find_next_zero_area(allocator->bitmap, allocator->size,
+                        0, len, 0);
+        if (addr < allocator->size) {
+                /* number zero is reserved; bitmap base is 1 */
+                *offset = 1 + addr;
+                bitmap_set(allocator->bitmap, addr, len);
+        } else {
+                err = -ENOMEM;
+        }
+        nvgpu_mutex_release(&allocator->lock);
+
+        return err;
+}
+
+void gk20a_comptaglines_free(struct gk20a_comptag_allocator *allocator,
+                             u32 offset, u32 len)
+{
+        /* number zero is reserved; bitmap base is 1 */
+        u32 addr = offset - 1;
+
+        WARN_ON(offset == 0);
+        WARN_ON(addr > allocator->size);
+        WARN_ON(addr + len > allocator->size);
+
+        nvgpu_mutex_acquire(&allocator->lock);
+        bitmap_clear(allocator->bitmap, addr, len);
+        nvgpu_mutex_release(&allocator->lock);
+}
+
+int gk20a_comptag_allocator_init(struct gk20a *g,
+                                 struct gk20a_comptag_allocator *allocator,
+                                 unsigned long size)
+{
+        nvgpu_mutex_init(&allocator->lock);
+
+        /*
+         * 0th comptag is special and is never used. The base for this bitmap
+         * is 1, and its size is one less than the size of comptag store.
+         */
+        size--;
+        allocator->bitmap = nvgpu_vzalloc(g,
+                                          BITS_TO_LONGS(size) * sizeof(long));
+        if (!allocator->bitmap)
+                return -ENOMEM;
+
+        allocator->size = size;
+
+        return 0;
+}
+
+void gk20a_comptag_allocator_destroy(struct gk20a *g,
+                                     struct gk20a_comptag_allocator *allocator)
+{
+        /*
+         * called only when exiting the driver (gk20a_remove, or unwinding the
+         * init stage); no users should be active, so taking the mutex is
+         * unnecessary here.
+         */
+        allocator->size = 0;
+        nvgpu_vfree(allocator->g, allocator->bitmap);
+}