linux/drivers/gpu/drm/drm_context.c

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/**
* \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_local_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_local_map *map = NULL;
struct drm_map_list *r_list = NULL;
mutex_lock(&dev->struct_mutex);
list_for_each_entry(r_list, &dev->maplist, head) {
drm: 32/64-bit DRM ioctl compatibility patch The patch is against a 2.6.11 kernel tree. I am running this with a 32-bit X server (compiled up from X.org CVS as of a couple of weeks ago) and 32-bit DRI libraries and clients. All the userland stuff is identical to what I am using under a 32-bit kernel on my G4 powerbook (which is a 32-bit machine of course). I haven't tried compiling up a 64-bit X server or clients yet. In the compatibility routines I have assumed that the kernel can safely access user addresses after set_fs(KERNEL_DS). That is, where an ioctl argument structure contains pointers to other structures, and those other structures are already compatible between the 32-bit and 64-bit ABIs (i.e. they only contain things like chars, shorts or ints), I just check the address with access_ok() and then pass it through to the 64-bit ioctl code. I believe this approach may not work on sparc64, but it does work on ppc64 and x86_64 at least. One tricky area which may need to be revisited is the question of how to handle the handles which we pass back to userspace to identify mappings. These handles are generated in the ADDMAP ioctl and then passed in as the offset value to mmap. However, offset values for mmap seem to be generated in other ways as well, particularly for AGP mappings. The approach I have ended up with is to generate a fake 32-bit handle only for _DRM_SHM mappings. The handles for other mappings (AGP, REG, FB) are physical addresses which are already limited to 32 bits, and generating fake handles for them created all sorts of problems in the mmap/nopage code. This patch has been updated to use the new compatibility ioctls. From: Paul Mackerras <paulus@samba.org> Signed-off-by: Dave Airlie <airlied@linux.ie>
2005-06-23 11:29:18 +00:00
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,
struct drm_file *file_priv, int new)
{
dev->last_context = new; /* PRE/POST: This is the _only_ writer. */
dev->last_switch = jiffies;
if (!_DRM_LOCK_IS_HELD(file_priv->master->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;
}
ctx_entry = kmalloc(sizeof(*ctx_entry), GFP_KERNEL);
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, file_priv, 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) {
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);
kfree(pos);
--dev->ctx_count;
}
}
}
mutex_unlock(&dev->ctxlist_mutex);
return 0;
}
/*@}*/