1 files changed, 471 insertions, 0 deletions
diff --git a/drivers/gpu/drm/drm_context.c b/drivers/gpu/drm/drm_context.c
new file mode 100644
index 000000000000..d505f695421f
--- /dev/null
+++ b/drivers/gpu/drm/drm_context.c
@@ -0,0 +1,471 @@
+/**
+ * \file drm_context.c
+ * IOCTLs for generic contexts
+ *
+ * \author Rickard E. (Rik) Faith <faith@valinux.com>
+ * \author Gareth Hughes <gareth@valinux.com>
+ */
+
+/*
+ * Created: Fri Nov 24 18:31:37 2000 by gareth@valinux.com
+ *
+ * Copyright 1999, 2000 Precision Insight, Inc., Cedar Park, Texas.
+ * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
+ * 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 (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
+ * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS 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.
+ */
+
+/*
+ * ChangeLog:
+ *  2001-11-16	Torsten Duwe <duwe@caldera.de>
+ *		added context constructor/destructor hooks,
+ *		needed by SiS driver's memory management.
+ */
+
+#include "drmP.h"
+
+/******************************************************************/
+/** \name Context bitmap support */
+/*@{*/
+
+/**
+ * Free a handle from the context bitmap.
+ *
+ * \param dev DRM device.
+ * \param ctx_handle context handle.
+ *
+ * Clears the bit specified by \p ctx_handle in drm_device::ctx_bitmap and the entry
+ * in drm_device::ctx_idr, while holding the drm_device::struct_mutex
+ * lock.
+ */
+void drm_ctxbitmap_free(struct drm_device * dev, int ctx_handle)
+{
+	mutex_lock(&dev->struct_mutex);
+	idr_remove(&dev->ctx_idr, ctx_handle);
+	mutex_unlock(&dev->struct_mutex);
+}
+
+/**
+ * Context bitmap allocation.
+ *
+ * \param dev DRM device.
+ * \return (non-negative) context handle on success or a negative number on failure.
+ *
+ * Allocate a new idr from drm_device::ctx_idr while holding the
+ * drm_device::struct_mutex lock.
+ */
+static int drm_ctxbitmap_next(struct drm_device * dev)
+{
+	int new_id;
+	int ret;
+
+again:
+	if (idr_pre_get(&dev->ctx_idr, GFP_KERNEL) == 0) {
+		DRM_ERROR("Out of memory expanding drawable idr\n");
+		return -ENOMEM;
+	}
+	mutex_lock(&dev->struct_mutex);
+	ret = idr_get_new_above(&dev->ctx_idr, NULL,
+				DRM_RESERVED_CONTEXTS, &new_id);
+	if (ret == -EAGAIN) {
+		mutex_unlock(&dev->struct_mutex);
+		goto again;
+	}
+	mutex_unlock(&dev->struct_mutex);
+	return new_id;
+}
+
+/**
+ * Context bitmap initialization.
+ *
+ * \param dev DRM device.
+ *
+ * Initialise the drm_device::ctx_idr
+ */
+int drm_ctxbitmap_init(struct drm_device * dev)
+{
+	idr_init(&dev->ctx_idr);
+	return 0;
+}
+
+/**
+ * Context bitmap cleanup.
+ *
+ * \param dev DRM device.
+ *
+ * Free all idr members using drm_ctx_sarea_free helper function
+ * while holding the drm_device::struct_mutex lock.
+ */
+void drm_ctxbitmap_cleanup(struct drm_device * dev)
+{
+	mutex_lock(&dev->struct_mutex);
+	idr_remove_all(&dev->ctx_idr);
+	mutex_unlock(&dev->struct_mutex);
+}
+
+/*@}*/
+
+/******************************************************************/
+/** \name Per Context SAREA Support */
+/*@{*/
+
+/**
+ * Get per-context SAREA.
+ *
+ * \param inode device inode.
+ * \param file_priv DRM file private.
+ * \param cmd command.
+ * \param arg user argument pointing to a drm_ctx_priv_map structure.
+ * \return zero on success or a negative number on failure.
+ *
+ * Gets the map from drm_device::ctx_idr with the handle specified and
+ * returns its handle.
+ */
+int drm_getsareactx(struct drm_device *dev, void *data,
+		    struct drm_file *file_priv)
+{
+	struct drm_ctx_priv_map *request = data;
+	struct drm_map *map;
+	struct drm_map_list *_entry;
+
+	mutex_lock(&dev->struct_mutex);
+
+	map = idr_find(&dev->ctx_idr, request->ctx_id);
+	if (!map) {
+		mutex_unlock(&dev->struct_mutex);
+		return -EINVAL;
+	}
+
+	mutex_unlock(&dev->struct_mutex);
+
+	request->handle = NULL;
+	list_for_each_entry(_entry, &dev->maplist, head) {
+		if (_entry->map == map) {
+			request->handle =
+			    (void *)(unsigned long)_entry->user_token;
+			break;
+		}
+	}
+	if (request->handle == NULL)
+		return -EINVAL;
+
+	return 0;
+}
+
+/**
+ * Set per-context SAREA.
+ *
+ * \param inode device inode.
+ * \param file_priv DRM file private.
+ * \param cmd command.
+ * \param arg user argument pointing to a drm_ctx_priv_map structure.
+ * \return zero on success or a negative number on failure.
+ *
+ * Searches the mapping specified in \p arg and update the entry in
+ * drm_device::ctx_idr with it.
+ */
+int drm_setsareactx(struct drm_device *dev, void *data,
+		    struct drm_file *file_priv)
+{
+	struct drm_ctx_priv_map *request = data;
+	struct drm_map *map = NULL;
+	struct drm_map_list *r_list = NULL;
+
+	mutex_lock(&dev->struct_mutex);
+	list_for_each_entry(r_list, &dev->maplist, head) {
+		if (r_list->map
+		    && r_list->user_token == (unsigned long) request->handle)
+			goto found;
+	}
+      bad:
+	mutex_unlock(&dev->struct_mutex);
+	return -EINVAL;
+
+      found:
+	map = r_list->map;
+	if (!map)
+		goto bad;
+
+	if (IS_ERR(idr_replace(&dev->ctx_idr, map, request->ctx_id)))
+		goto bad;
+
+	mutex_unlock(&dev->struct_mutex);
+
+	return 0;
+}
+
+/*@}*/
+
+/******************************************************************/
+/** \name The actual DRM context handling routines */
+/*@{*/
+
+/**
+ * Switch context.
+ *
+ * \param dev DRM device.
+ * \param old old context handle.
+ * \param new new context handle.
+ * \return zero on success or a negative number on failure.
+ *
+ * Attempt to set drm_device::context_flag.
+ */
+static int drm_context_switch(struct drm_device * dev, int old, int new)
+{
+	if (test_and_set_bit(0, &dev->context_flag)) {
+		DRM_ERROR("Reentering -- FIXME\n");
+		return -EBUSY;
+	}
+
+	DRM_DEBUG("Context switch from %d to %d\n", old, new);
+
+	if (new == dev->last_context) {
+		clear_bit(0, &dev->context_flag);
+		return 0;
+	}
+
+	return 0;
+}
+
+/**
+ * Complete context switch.
+ *
+ * \param dev DRM device.
+ * \param new new context handle.
+ * \return zero on success or a negative number on failure.
+ *
+ * Updates drm_device::last_context and drm_device::last_switch. Verifies the
+ * hardware lock is held, clears the drm_device::context_flag and wakes up
+ * drm_device::context_wait.
+ */
+static int drm_context_switch_complete(struct drm_device * dev, int new)
+{
+	dev->last_context = new;	/* PRE/POST: This is the _only_ writer. */
+	dev->last_switch = jiffies;
+
+	if (!_DRM_LOCK_IS_HELD(dev->lock.hw_lock->lock)) {
+		DRM_ERROR("Lock isn't held after context switch\n");
+	}
+
+	/* If a context switch is ever initiated
+	   when the kernel holds the lock, release
+	   that lock here. */
+	clear_bit(0, &dev->context_flag);
+	wake_up(&dev->context_wait);
+
+	return 0;
+}
+
+/**
+ * Reserve contexts.
+ *
+ * \param inode device inode.
+ * \param file_priv DRM file private.
+ * \param cmd command.
+ * \param arg user argument pointing to a drm_ctx_res structure.
+ * \return zero on success or a negative number on failure.
+ */
+int drm_resctx(struct drm_device *dev, void *data,
+	       struct drm_file *file_priv)
+{
+	struct drm_ctx_res *res = data;
+	struct drm_ctx ctx;
+	int i;
+
+	if (res->count >= DRM_RESERVED_CONTEXTS) {
+		memset(&ctx, 0, sizeof(ctx));
+		for (i = 0; i < DRM_RESERVED_CONTEXTS; i++) {
+			ctx.handle = i;
+			if (copy_to_user(&res->contexts[i], &ctx, sizeof(ctx)))
+				return -EFAULT;
+		}
+	}
+	res->count = DRM_RESERVED_CONTEXTS;
+
+	return 0;
+}
+
+/**
+ * Add context.
+ *
+ * \param inode device inode.
+ * \param file_priv DRM file private.
+ * \param cmd command.
+ * \param arg user argument pointing to a drm_ctx structure.
+ * \return zero on success or a negative number on failure.
+ *
+ * Get a new handle for the context and copy to userspace.
+ */
+int drm_addctx(struct drm_device *dev, void *data,
+	       struct drm_file *file_priv)
+{
+	struct drm_ctx_list *ctx_entry;
+	struct drm_ctx *ctx = data;
+
+	ctx->handle = drm_ctxbitmap_next(dev);
+	if (ctx->handle == DRM_KERNEL_CONTEXT) {
+		/* Skip kernel's context and get a new one. */
+		ctx->handle = drm_ctxbitmap_next(dev);
+	}
+	DRM_DEBUG("%d\n", ctx->handle);
+	if (ctx->handle == -1) {
+		DRM_DEBUG("Not enough free contexts.\n");
+		/* Should this return -EBUSY instead? */
+		return -ENOMEM;
+	}
+
+	if (ctx->handle != DRM_KERNEL_CONTEXT) {
+		if (dev->driver->context_ctor)
+			if (!dev->driver->context_ctor(dev, ctx->handle)) {
+				DRM_DEBUG("Running out of ctxs or memory.\n");
+				return -ENOMEM;
+			}
+	}
+
+	ctx_entry = drm_alloc(sizeof(*ctx_entry), DRM_MEM_CTXLIST);
+	if (!ctx_entry) {
+		DRM_DEBUG("out of memory\n");
+		return -ENOMEM;
+	}
+
+	INIT_LIST_HEAD(&ctx_entry->head);
+	ctx_entry->handle = ctx->handle;
+	ctx_entry->tag = file_priv;
+
+	mutex_lock(&dev->ctxlist_mutex);
+	list_add(&ctx_entry->head, &dev->ctxlist);
+	++dev->ctx_count;
+	mutex_unlock(&dev->ctxlist_mutex);
+
+	return 0;
+}
+
+int drm_modctx(struct drm_device *dev, void *data, struct drm_file *file_priv)
+{
+	/* This does nothing */
+	return 0;
+}
+
+/**
+ * Get context.
+ *
+ * \param inode device inode.
+ * \param file_priv DRM file private.
+ * \param cmd command.
+ * \param arg user argument pointing to a drm_ctx structure.
+ * \return zero on success or a negative number on failure.
+ */
+int drm_getctx(struct drm_device *dev, void *data, struct drm_file *file_priv)
+{
+	struct drm_ctx *ctx = data;
+
+	/* This is 0, because we don't handle any context flags */
+	ctx->flags = 0;
+
+	return 0;
+}
+
+/**
+ * Switch context.
+ *
+ * \param inode device inode.
+ * \param file_priv DRM file private.
+ * \param cmd command.
+ * \param arg user argument pointing to a drm_ctx structure.
+ * \return zero on success or a negative number on failure.
+ *
+ * Calls context_switch().
+ */
+int drm_switchctx(struct drm_device *dev, void *data,
+		  struct drm_file *file_priv)
+{
+	struct drm_ctx *ctx = data;
+
+	DRM_DEBUG("%d\n", ctx->handle);
+	return drm_context_switch(dev, dev->last_context, ctx->handle);
+}
+
+/**
+ * New context.
+ *
+ * \param inode device inode.
+ * \param file_priv DRM file private.
+ * \param cmd command.
+ * \param arg user argument pointing to a drm_ctx structure.
+ * \return zero on success or a negative number on failure.
+ *
+ * Calls context_switch_complete().
+ */
+int drm_newctx(struct drm_device *dev, void *data,
+	       struct drm_file *file_priv)
+{
+	struct drm_ctx *ctx = data;
+
+	DRM_DEBUG("%d\n", ctx->handle);
+	drm_context_switch_complete(dev, ctx->handle);
+
+	return 0;
+}
+
+/**
+ * Remove context.
+ *
+ * \param inode device inode.
+ * \param file_priv DRM file private.
+ * \param cmd command.
+ * \param arg user argument pointing to a drm_ctx structure.
+ * \return zero on success or a negative number on failure.
+ *
+ * If not the special kernel context, calls ctxbitmap_free() to free the specified context.
+ */
+int drm_rmctx(struct drm_device *dev, void *data,
+	      struct drm_file *file_priv)
+{
+	struct drm_ctx *ctx = data;
+
+	DRM_DEBUG("%d\n", ctx->handle);
+	if (ctx->handle == DRM_KERNEL_CONTEXT + 1) {
+		file_priv->remove_auth_on_close = 1;
+	}
+	if (ctx->handle != DRM_KERNEL_CONTEXT) {
+		if (dev->driver->context_dtor)
+			dev->driver->context_dtor(dev, ctx->handle);
+		drm_ctxbitmap_free(dev, ctx->handle);
+	}
+
+	mutex_lock(&dev->ctxlist_mutex);
+	if (!list_empty(&dev->ctxlist)) {
+		struct drm_ctx_list *pos, *n;
+
+		list_for_each_entry_safe(pos, n, &dev->ctxlist, head) {
+			if (pos->handle == ctx->handle) {
+				list_del(&pos->head);
+				drm_free(pos, sizeof(*pos), DRM_MEM_CTXLIST);
+				--dev->ctx_count;
+			}
+		}
+	}
+	mutex_unlock(&dev->ctxlist_mutex);
+
+	return 0;
+}
+
+/*@}*/