gpu: nvgpu: Implement 64k large page support

Implement support for 64kB large page size. Add an API to create an
address space via IOCTL so that we can accept flags, and assign one
flag for enabling 64kB large page size.

Also adds APIs to set per-context large page size. This is possible
only on Maxwell, so return error if caller tries to set large page
size on Kepler.

Default large page size is still 128kB.

Change-Id: I20b51c8f6d4a984acae8411ace3de9000c78e82f
Signed-off-by: Terje Bergstrom <tbergstrom@nvidia.com>

1 files changed, 53 insertions, 0 deletions

diff --git a/drivers/gpu/nvgpu/gk20a/ctrl_gk20a.c b/drivers/gpu/nvgpu/gk20a/ctrl_gk20a.c
index ca587d00..6969a3a7 100644
--- a/drivers/gpu/nvgpu/gk20a/ctrl_gk20a.c
+++ b/drivers/gpu/nvgpu/gk20a/ctrl_gk20a.c
@@ -16,6 +16,8 @@
 
 #include <linux/highmem.h>
 #include <linux/cdev.h>
+#include <linux/file.h>
+#include <linux/anon_inodes.h>
 #include <uapi/linux/nvgpu.h>
 
 #include "gk20a.h"
@@ -148,6 +150,53 @@ static int gk20a_ctrl_mark_compressible_write(
         return ret;
 }
 
+static int gk20a_ctrl_alloc_as(
+                struct gk20a *g,
+                struct nvgpu_alloc_as_args *args)
+{
+        struct platform_device *dev = g->dev;
+        struct gk20a_as_share *as_share;
+        int err;
+        int fd;
+        struct file *file;
+        char *name;
+
+        err = get_unused_fd_flags(O_RDWR);
+        if (err < 0)
+                return err;
+        fd = err;
+
+        name = kasprintf(GFP_KERNEL, "nvhost-%s-fd%d",
+                        dev_name(&dev->dev), fd);
+
+        file = anon_inode_getfile(name, g->as.cdev.ops, NULL, O_RDWR);
+        kfree(name);
+        if (IS_ERR(file)) {
+                err = PTR_ERR(file);
+                goto clean_up;
+        }
+        fd_install(fd, file);
+
+        err = gk20a_get_client(g);
+        if (err)
+                goto clean_up;
+
+        err = gk20a_as_alloc_share(&g->as, args->big_page_size, &as_share);
+        if (err)
+                goto clean_up_client;
+
+        file->private_data = as_share;
+
+        args->as_fd = fd;
+        return 0;
+
+clean_up_client:
+        gk20a_put_client(g);
+clean_up:
+        put_unused_fd(fd);
+        return err;
+}
+
 long gk20a_ctrl_dev_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 {
         struct platform_device *dev = filp->private_data;
@@ -309,6 +358,10 @@ long gk20a_ctrl_dev_ioctl(struct file *filp, unsigned int cmd, unsigned long arg
                 err = gk20a_ctrl_mark_compressible_write(g,
                         (struct nvgpu_gpu_mark_compressible_write_args *)buf);
                 break;
+        case NVGPU_GPU_IOCTL_ALLOC_AS:
+                err = gk20a_ctrl_alloc_as(g,
+                        (struct nvgpu_alloc_as_args *)buf);
+                break;
         default:
                 dev_dbg(dev_from_gk20a(g), "unrecognized gpu ioctl cmd: 0x%x", cmd);
                 err = -ENOTTY;