Move mmfs ioctls into the DRM. Untested.

5 files changed, 414 insertions, 2 deletions

diff --git a/linux-core/Makefile.kernel b/linux-core/Makefile.kernel
index c4975924..4580a738 100644
--- a/linux-core/Makefile.kernel
+++ b/linux-core/Makefile.kernel
@@ -14,7 +14,7 @@ drm-objs    := drm_auth.o drm_bufs.o drm_context.o drm_dma.o drm_drawable.o \
 		drm_memory_debug.o ati_pcigart.o drm_sman.o \
 		drm_hashtab.o drm_memrange.o drm_object.o drm_compat.o \
 	        drm_fence.o drm_ttm.o drm_bo.o drm_bo_move.o drm_bo_lock.o \
-		drm_regman.o
+		drm_regman.o drm_mm.o
 tdfx-objs   := tdfx_drv.o
 r128-objs   := r128_drv.o r128_cce.o r128_state.o r128_irq.o
 mga-objs    := mga_drv.o mga_dma.o mga_state.o mga_warp.o mga_irq.o
diff --git a/linux-core/drmP.h b/linux-core/drmP.h
index ea8a997f..29dd4321 100644
--- a/linux-core/drmP.h
+++ b/linux-core/drmP.h
@@ -107,7 +107,7 @@ struct drm_file;
 #define DRIVER_IRQ_SHARED  0x80
 #define DRIVER_DMA_QUEUE   0x100
 #define DRIVER_FB_DMA      0x200
-
+#define DRIVER_MM	   0x400
 
 /*@}*/
 
@@ -427,6 +427,11 @@ struct drm_file {
 
 	struct list_head refd_objects;
 
+	/** Mapping of mm object handles to object pointers. */
+	struct idr object_idr;
+	/** Lock for synchronization of access to object_idr. */
+	spinlock_t table_lock;
+
 	struct drm_open_hash refd_object_hash[_DRM_NO_REF_TYPES];
 	struct file *filp;
 	void *driver_priv;
@@ -604,6 +609,26 @@ struct drm_ati_pcigart_info {
 	int table_size;
 };
 
+/**
+ * This structure defines the drm_mm memory object, which will be used by the
+ * DRM for its buffer objects.
+ */
+struct drm_mm_object {
+	/** File representing the shmem storage */
+	struct file *filp;
+
+	spinlock_t lock;
+
+	/**
+	 * Size of the object, in bytes.  Immutable over the object's
+	 * lifetime.
+	 */
+	size_t size;
+
+	/** Reference count of this object, protected by object_lock */
+	int refcount;
+};
+
 #include "drm_objects.h"
 
 /**
@@ -1259,6 +1284,22 @@ static inline struct drm_memrange *drm_get_mm(struct drm_memrange_node *block)
 	return block->mm;
 }
 
+/* Memory manager (drm_mm.c) */
+void drm_mm_object_reference(struct drm_mm_object *obj);
+void drm_mm_object_unreference(struct drm_mm_object *obj);
+int drm_mm_alloc_ioctl(struct drm_device *dev, void *data,
+		       struct drm_file *file_priv);
+int drm_mm_unreference_ioctl(struct drm_device *dev, void *data,
+			     struct drm_file *file_priv);
+int drm_mm_pread_ioctl(struct drm_device *dev, void *data,
+		       struct drm_file *file_priv);
+int drm_mm_pwrite_ioctl(struct drm_device *dev, void *data,
+			struct drm_file *file_priv);
+int drm_mm_mmap_ioctl(struct drm_device *dev, void *data,
+		      struct drm_file *file_priv);
+void drm_mm_open(struct drm_file *file_private);
+void drm_mm_release(struct drm_file *file_private);
+
 extern void drm_core_ioremap(struct drm_map *map, struct drm_device *dev);
 extern void drm_core_ioremapfree(struct drm_map *map, struct drm_device *dev);
 
diff --git a/linux-core/drm_drv.c b/linux-core/drm_drv.c
index b5bd3616..2847f51b 100644
--- a/linux-core/drm_drv.c
+++ b/linux-core/drm_drv.c
@@ -150,6 +150,12 @@ static struct drm_ioctl_desc drm_ioctls[] = {
 	DRM_IOCTL_DEF(DRM_IOCTL_BO_VERSION, drm_bo_version_ioctl, 0),
 
 	DRM_IOCTL_DEF(DRM_IOCTL_MM_INFO, drm_mm_info_ioctl, 0),
+
+	DRM_IOCTL_DEF(DRM_IOCTL_MM_ALLOC, drm_mm_alloc_ioctl, 0),
+	DRM_IOCTL_DEF(DRM_IOCTL_MM_UNREFERENCE, drm_mm_unreference_ioctl, 0),
+	DRM_IOCTL_DEF(DRM_IOCTL_MM_PREAD, drm_mm_pread_ioctl, 0),
+	DRM_IOCTL_DEF(DRM_IOCTL_MM_PWRITE, drm_mm_pwrite_ioctl, 0),
+	DRM_IOCTL_DEF(DRM_IOCTL_MM_MMAP, drm_mm_mmap_ioctl, 0),
 };
 
 #define DRM_CORE_IOCTL_COUNT	ARRAY_SIZE( drm_ioctls )
diff --git a/linux-core/drm_fops.c b/linux-core/drm_fops.c
index a4c76f75..2213230c 100644
--- a/linux-core/drm_fops.c
+++ b/linux-core/drm_fops.c
@@ -274,6 +274,9 @@ static int drm_open_helper(struct inode *inode, struct file *filp,
 		goto out_free;
 	}
 
+	if (dev->driver->driver_features & DRIVER_MM)
+		drm_mm_open(priv);
+
 	if (dev->driver->open) {
 		ret = dev->driver->open(dev, priv);
 		if (ret < 0)
@@ -447,6 +450,9 @@ int drm_release(struct inode *inode, struct file *filp)
 		dev->driver->reclaim_buffers(dev, file_priv);
 	}
 
+	if (dev->driver->driver_features & DRIVER_MM)
+		drm_mm_release(file_priv);
+
 	drm_fasync(-1, filp, 0);
 
 	mutex_lock(&dev->ctxlist_mutex);
diff --git a/linux-core/drm_mm.c b/linux-core/drm_mm.c
new file mode 100644
index 00000000..7e9fe39c
--- /dev/null
+++ b/linux-core/drm_mm.c
@@ -0,0 +1,359 @@
+/*
+ * Copyright © 2008 Intel Corporation
+ *
+ * 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 (including the next
+ * paragraph) 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.
+ *
+ * Authors:
+ *    Eric Anholt <eric@anholt.net>
+ *
+ */
+
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/mm.h>
+#include <linux/uaccess.h>
+#include <linux/fs.h>
+#include <linux/file.h>
+#include <linux/module.h>
+#include <linux/mman.h>
+#include <linux/pagemap.h>
+#include "drmP.h"
+
+/** @file drm_mm.c
+ *
+ * This file provides some of the base ioctls and library routines for
+ * the graphics memory manager implemented by each device driver.
+ *
+ * Because various devices have different requirements in terms of
+ * synchronization and migration strategies, implementing that is left up to
+ * the driver, and all that the general API provides should be generic --
+ * allocating objects, reading/writing data with the cpu, freeing objects.
+ * Even there, platform-dependent optimizations for reading/writing data with
+ * the CPU mean we'll likely hook those out to driver-specific calls.  However,
+ * the DRI2 implementation wants to have at least allocate/mmap be generic.
+ *
+ * The goal was to have swap-backed object allocation managed through
+ * struct file.  However, file descriptors as handles to a struct file have
+ * two major failings:
+ * - Process limits prevent more than 1024 or so being used at a time by
+ *   default.
+ * - Inability to allocate high fds will aggravate the X Server's select()
+ *   handling, and likely that of many GL client applications as well.
+ *
+ * This led to a plan of using our own integer IDs (called handles, following
+ * DRM terminology) to mimic fds, and implement the fd syscalls we need as
+ * ioctls.  The objects themselves will still include the struct file so
+ * that we can transition to fds if the required kernel infrastructure shows
+ * up at a later data, and as our interface with shmfs for memory allocation.
+ */
+
+static struct drm_mm_object *
+drm_mm_object_alloc(size_t size)
+{
+	struct drm_mm_object *obj;
+
+	BUG_ON((size & (PAGE_SIZE - 1)) != 0);
+
+	obj = kcalloc(1, sizeof(*obj), GFP_KERNEL);
+
+	obj->filp = shmem_file_setup("drm mm object", size, 0);
+	if (IS_ERR(obj->filp)) {
+		kfree(obj);
+		return NULL;
+	}
+
+	obj->refcount = 1;
+
+	return obj;
+}
+
+/**
+ * Removes the mapping from handle to filp for this object.
+ */
+static int
+drm_mm_handle_delete(struct drm_file *filp, int handle)
+{
+	struct drm_mm_object *obj;
+
+	/* This is gross. The idr system doesn't let us try a delete and
+	 * return an error code.  It just spews if you fail at deleting.
+	 * So, we have to grab a lock around finding the object and then
+	 * doing the delete on it and dropping the refcount, or the user
+	 * could race us to double-decrement the refcount and cause a
+	 * use-after-free later.  Given the frequency of our handle lookups,
+	 * we may want to use ida for number allocation and a hash table
+	 * for the pointers, anyway.
+	 */
+	spin_lock(&filp->table_lock);
+
+	/* Check if we currently have a reference on the object */
+	obj = idr_find(&filp->object_idr, handle);
+	if (obj == NULL) {
+		spin_unlock(&filp->table_lock);
+		return -EINVAL;
+	}
+
+	/* Release reference and decrement refcount. */
+	idr_remove(&filp->object_idr, handle);
+	drm_mm_object_unreference(obj);
+
+	spin_unlock(&filp->table_lock);
+
+	return 0;
+}
+
+/** Returns a reference to the object named by the handle. */
+static struct drm_mm_object *
+drm_mm_object_lookup(struct drm_file *filp, int handle)
+{
+	struct drm_mm_object *obj;
+
+	spin_lock(&filp->table_lock);
+
+	/* Check if we currently have a reference on the object */
+	obj = idr_find(&filp->object_idr, handle);
+	if (obj == NULL) {
+		spin_unlock(&filp->table_lock);
+		return NULL;
+	}
+
+	drm_mm_object_reference(obj);
+
+	spin_unlock(&filp->table_lock);
+
+	return obj;
+}
+
+
+/**
+ * Allocates a new mm object and returns a handle to it.
+ */
+int
+drm_mm_alloc_ioctl(struct drm_device *dev, void *data,
+		   struct drm_file *file_priv)
+{
+	struct drm_mm_alloc_args *args = data;
+	struct drm_mm_object *obj;
+	int handle, ret;
+
+	/* Round requested size up to page size */
+	args->size = (args->size + PAGE_SIZE - 1) & ~(PAGE_SIZE - 1);
+
+	/* Allocate the new object */
+	obj = drm_mm_object_alloc(args->size);
+	if (obj == NULL)
+		return -ENOMEM;
+
+	/* Get the user-visible handle using idr.
+	 *
+	 * I'm not really sure why the idr api needs us to do this in two
+	 * repeating steps.  It handles internal locking of its data
+	 * structure, yet insists that we keep its memory allocation step
+	 * separate from its slot-finding step for locking purposes.
+	 */
+	do {
+		if (idr_pre_get(&file_priv->object_idr, GFP_KERNEL) == 0) {
+			kfree(obj);
+			return -EFAULT;
+		}
+
+		ret = idr_get_new(&file_priv->object_idr, obj, &handle);
+	} while (ret == -EAGAIN);
+
+	if (ret != 0) {
+		drm_mm_object_unreference(obj);
+		return -EFAULT;
+	}
+
+	args->handle = handle;
+
+	return 0;
+}
+
+/**
+ * Releases the handle to an mm object.
+ */
+int
+drm_mm_unreference_ioctl(struct drm_device *dev, void *data,
+			 struct drm_file *file_priv)
+{
+	struct drm_mm_unreference_args *args = data;
+	int ret;
+
+	ret = drm_mm_handle_delete(file_priv, args->handle);
+
+	return ret;
+}
+
+/**
+ * Reads data from the object referenced by handle.
+ *
+ * On error, the contents of *data are undefined.
+ */
+int
+drm_mm_pread_ioctl(struct drm_device *dev, void *data,
+		   struct drm_file *file_priv)
+{
+	struct drm_mm_pread_args *args = data;
+	struct drm_mm_object *obj;
+	ssize_t read;
+	loff_t offset;
+
+	obj = drm_mm_object_lookup(file_priv, args->handle);
+	if (obj == NULL)
+		return -EINVAL;
+
+	offset = args->offset;
+
+	read = obj->filp->f_op->read(obj->filp, (char __user *)args->data,
+				     args->size, &offset);
+	if (read != args->size) {
+		drm_mm_object_unreference(obj);
+		if (read < 0)
+			return read;
+		else
+			return -EINVAL;
+	}
+
+	drm_mm_object_unreference(obj);
+
+	return 0;
+}
+
+/**
+ * Maps the contents of an object, returning the address it is mapped
+ * into.
+ *
+ * While the mapping holds a reference on the contents of the object, it doesn't
+ * imply a ref on the object itself.
+ */
+int
+drm_mm_mmap_ioctl(struct drm_device *dev, void *data,
+		  struct drm_file *file_priv)
+{
+	struct drm_mm_mmap_args *args = data;
+	struct drm_mm_object *obj;
+	loff_t offset;
+
+	obj = drm_mm_object_lookup(file_priv, args->handle);
+	if (obj == NULL)
+		return -EINVAL;
+
+	offset = args->offset;
+
+	down_write(&current->mm->mmap_sem);
+	args->addr = (void *)do_mmap(obj->filp, 0, args->size,
+				    PROT_READ | PROT_WRITE, MAP_SHARED,
+				    args->offset);
+	up_write(&current->mm->mmap_sem);
+
+	drm_mm_object_unreference(obj);
+
+	return 0;
+}
+
+/**
+ * Writes data to the object referenced by handle.
+ *
+ * On error, the contents of the buffer that were to be modified are undefined.
+ */
+int
+drm_mm_pwrite_ioctl(struct drm_device *dev, void *data,
+		    struct drm_file *file_priv)
+{
+	struct drm_mm_pwrite_args *args = data;
+	struct drm_mm_object *obj;
+	ssize_t written;
+	loff_t offset;
+
+	obj = drm_mm_object_lookup(file_priv, args->handle);
+	if (obj == NULL)
+		return -EINVAL;
+
+	offset = args->offset;
+
+	written = obj->filp->f_op->write(obj->filp, (char __user *)args->data,
+					 args->size, &offset);
+	if (written != args->size) {
+		drm_mm_object_unreference(obj);
+		if (written < 0)
+			return written;
+		else
+			return -EINVAL;
+	}
+
+	drm_mm_object_unreference(obj);
+
+	return 0;
+}
+
+/**
+ * Called at device open time, sets up the structure for handling refcounting
+ * of mm objects.
+ */
+void
+drm_mm_open(struct drm_file *file_private)
+{
+	idr_init(&file_private->object_idr);
+}
+
+/** Called at device close to release the file's references on objects. */
+static int
+drm_mm_object_release(int id, void *ptr, void *data)
+{
+	struct drm_mm_object *obj = ptr;
+
+	drm_mm_object_unreference(obj);
+
+	return 0;
+}
+
+/**
+ * Called at close time when the filp is going away.
+ *
+ * Releases any remaining references on objects by this filp.
+ */
+void
+drm_mm_release(struct drm_file *file_private)
+{
+	idr_for_each(&file_private->object_idr, &drm_mm_object_release, NULL);
+
+	idr_destroy(&file_private->object_idr);
+}
+
+void
+drm_mm_object_reference(struct drm_mm_object *obj)
+{
+	spin_lock(&obj->lock);
+	obj->refcount++;
+	spin_unlock(&obj->lock);
+}
+
+void
+drm_mm_object_unreference(struct drm_mm_object *obj)
+{
+	spin_lock(&obj->lock);
+	obj->refcount--;
+	spin_unlock(&obj->lock);
+	if (obj->refcount == 0) {
+		fput(obj->filp);
+		kfree(obj);
+	}
+}