OpenCloudOS-Kernel/drivers/gpu/drm/drm_drv.c

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/*
* Created: Fri Jan 19 10:48:35 2001 by faith@acm.org
*
* Copyright 2001 VA Linux Systems, Inc., Sunnyvale, California.
* All Rights Reserved.
*
* Author Rickard E. (Rik) Faith <faith@valinux.com>
*
* 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
* PRECISION INSIGHT 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.
*/
#include <linux/debugfs.h>
drm: add pseudo filesystem for shared inodes Our current DRM design uses a single address_space for all users of the same DRM device. However, there is no way to create an anonymous address_space without an underlying inode. Therefore, we wait for the first ->open() callback on a registered char-dev and take-over the inode of the char-dev. This worked well so far, but has several drawbacks: - We screw with FS internals and rely on some non-obvious invariants like inode->i_mapping being the same as inode->i_data for char-devs. - We don't have any address_space prior to the first ->open() from user-space. This leads to ugly fallback code and we cannot allocate global objects early. As pointed out by Al-Viro, fs/anon_inode.c is *not* supposed to be used by drivers for anonymous inode-allocation. Therefore, this patch follows the proposed alternative solution and adds a pseudo filesystem mount-point to DRM. We can then allocate private inodes including a private address_space for each DRM device at initialization time. Note that we could use: sysfs_get_inode(sysfs_mnt->mnt_sb, drm_device->dev->kobj.sd); to get access to the underlying sysfs-inode of a "struct device" object. However, most of this information is currently hidden and it's not clear whether this address_space is suitable for driver access. Thus, unless linux allows anonymous address_space objects or driver-core provides a public inode per device, we're left with our own private internal mount point. Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
2014-01-03 21:09:47 +08:00
#include <linux/fs.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
drm: add pseudo filesystem for shared inodes Our current DRM design uses a single address_space for all users of the same DRM device. However, there is no way to create an anonymous address_space without an underlying inode. Therefore, we wait for the first ->open() callback on a registered char-dev and take-over the inode of the char-dev. This worked well so far, but has several drawbacks: - We screw with FS internals and rely on some non-obvious invariants like inode->i_mapping being the same as inode->i_data for char-devs. - We don't have any address_space prior to the first ->open() from user-space. This leads to ugly fallback code and we cannot allocate global objects early. As pointed out by Al-Viro, fs/anon_inode.c is *not* supposed to be used by drivers for anonymous inode-allocation. Therefore, this patch follows the proposed alternative solution and adds a pseudo filesystem mount-point to DRM. We can then allocate private inodes including a private address_space for each DRM device at initialization time. Note that we could use: sysfs_get_inode(sysfs_mnt->mnt_sb, drm_device->dev->kobj.sd); to get access to the underlying sysfs-inode of a "struct device" object. However, most of this information is currently hidden and it's not clear whether this address_space is suitable for driver access. Thus, unless linux allows anonymous address_space objects or driver-core provides a public inode per device, we're left with our own private internal mount point. Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
2014-01-03 21:09:47 +08:00
#include <linux/mount.h>
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 16:04:11 +08:00
#include <linux/slab.h>
#include <drm/drmP.h>
#include <drm/drm_core.h>
#include "drm_legacy.h"
#include "drm_internal.h"
unsigned int drm_debug = 0; /* bitmask of DRM_UT_x */
EXPORT_SYMBOL(drm_debug);
MODULE_AUTHOR(CORE_AUTHOR);
MODULE_DESCRIPTION(CORE_DESC);
MODULE_LICENSE("GPL and additional rights");
MODULE_PARM_DESC(debug, "Enable debug output");
module_param_named(debug, drm_debug, int, 0600);
static DEFINE_SPINLOCK(drm_minor_lock);
static struct idr drm_minors_idr;
static struct dentry *drm_debugfs_root;
void drm_err(const char *format, ...)
{
struct va_format vaf;
va_list args;
va_start(args, format);
vaf.fmt = format;
vaf.va = &args;
printk(KERN_ERR "[" DRM_NAME ":%ps] *ERROR* %pV",
__builtin_return_address(0), &vaf);
va_end(args);
}
EXPORT_SYMBOL(drm_err);
void drm_ut_debug_printk(const char *function_name, const char *format, ...)
2009-06-02 14:09:47 +08:00
{
struct va_format vaf;
2009-06-02 14:09:47 +08:00
va_list args;
va_start(args, format);
vaf.fmt = format;
vaf.va = &args;
printk(KERN_DEBUG "[" DRM_NAME ":%s] %pV", function_name, &vaf);
va_end(args);
2009-06-02 14:09:47 +08:00
}
EXPORT_SYMBOL(drm_ut_debug_printk);
struct drm_master *drm_master_create(struct drm_minor *minor)
{
struct drm_master *master;
master = kzalloc(sizeof(*master), GFP_KERNEL);
if (!master)
return NULL;
kref_init(&master->refcount);
spin_lock_init(&master->lock.spinlock);
init_waitqueue_head(&master->lock.lock_queue);
idr_init(&master->magic_map);
master->minor = minor;
return master;
}
struct drm_master *drm_master_get(struct drm_master *master)
{
kref_get(&master->refcount);
return master;
}
EXPORT_SYMBOL(drm_master_get);
static void drm_master_destroy(struct kref *kref)
{
struct drm_master *master = container_of(kref, struct drm_master, refcount);
struct drm_device *dev = master->minor->dev;
struct drm_map_list *r_list, *list_temp;
mutex_lock(&dev->struct_mutex);
if (dev->driver->master_destroy)
dev->driver->master_destroy(dev, master);
list_for_each_entry_safe(r_list, list_temp, &dev->maplist, head) {
if (r_list->master == master) {
drm_legacy_rmmap_locked(dev, r_list->map);
r_list = NULL;
}
}
mutex_unlock(&dev->struct_mutex);
idr_destroy(&master->magic_map);
kfree(master->unique);
kfree(master);
}
void drm_master_put(struct drm_master **master)
{
kref_put(&(*master)->refcount, drm_master_destroy);
*master = NULL;
}
EXPORT_SYMBOL(drm_master_put);
int drm_setmaster_ioctl(struct drm_device *dev, void *data,
struct drm_file *file_priv)
{
int ret = 0;
mutex_lock(&dev->master_mutex);
if (file_priv->is_master)
goto out_unlock;
if (file_priv->minor->master) {
ret = -EINVAL;
goto out_unlock;
}
if (!file_priv->master) {
ret = -EINVAL;
goto out_unlock;
}
drm: fix returning -EINVAL on setmaster if another master is active We link every DRM "file_priv" to a "drm_master" structure. Currently, the drmSetMaster() call returns 0 when there is _any_ active master associated with the "drm_master" structure of the calling "file_priv". This means, that after drmSetMaster() we are not guaranteed to be DRM-Master and might not be able to perform mode-setting. A way to reproduce this is by starting weston with the DRM backend from within an X-console (eg., xterm). Because the xserver's "drm_master" is currently active, weston is assigned to the same master but is inactive because its VT is inactive and the xserver is still active. But when "fake-activating" weston, it calls drmSetMaster(). With current behavior this returns "0/success" and weston thinks that it is DRM-Master, even though it is not (as the xserver is still DRM-Master). Expected behavior would be drmSetMaster() to return -EINVAL, because the xserver is still DRM-Master. This patch changes exactly that. The only way this bogus behavior would be useful is for clients to check whether their associated "drm_master" is currently the active DRM-Master. But this logic fails if no DRM-Master is currently active at all. Because then the client itself would become DRM-Master (if it is root) and this makes this whole thing useles. Also note that the second "if-condition": file_priv->minor->master != file_priv->master is always true and can be skipped. Signed-off-by: David Herrmann <dh.herrmann@googlemail.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2012-11-15 21:04:37 +08:00
if (!file_priv->allowed_master) {
ret = drm_new_set_master(dev, file_priv);
goto out_unlock;
}
drm: fix returning -EINVAL on setmaster if another master is active We link every DRM "file_priv" to a "drm_master" structure. Currently, the drmSetMaster() call returns 0 when there is _any_ active master associated with the "drm_master" structure of the calling "file_priv". This means, that after drmSetMaster() we are not guaranteed to be DRM-Master and might not be able to perform mode-setting. A way to reproduce this is by starting weston with the DRM backend from within an X-console (eg., xterm). Because the xserver's "drm_master" is currently active, weston is assigned to the same master but is inactive because its VT is inactive and the xserver is still active. But when "fake-activating" weston, it calls drmSetMaster(). With current behavior this returns "0/success" and weston thinks that it is DRM-Master, even though it is not (as the xserver is still DRM-Master). Expected behavior would be drmSetMaster() to return -EINVAL, because the xserver is still DRM-Master. This patch changes exactly that. The only way this bogus behavior would be useful is for clients to check whether their associated "drm_master" is currently the active DRM-Master. But this logic fails if no DRM-Master is currently active at all. Because then the client itself would become DRM-Master (if it is root) and this makes this whole thing useles. Also note that the second "if-condition": file_priv->minor->master != file_priv->master is always true and can be skipped. Signed-off-by: David Herrmann <dh.herrmann@googlemail.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2012-11-15 21:04:37 +08:00
file_priv->minor->master = drm_master_get(file_priv->master);
file_priv->is_master = 1;
drm: fix returning -EINVAL on setmaster if another master is active We link every DRM "file_priv" to a "drm_master" structure. Currently, the drmSetMaster() call returns 0 when there is _any_ active master associated with the "drm_master" structure of the calling "file_priv". This means, that after drmSetMaster() we are not guaranteed to be DRM-Master and might not be able to perform mode-setting. A way to reproduce this is by starting weston with the DRM backend from within an X-console (eg., xterm). Because the xserver's "drm_master" is currently active, weston is assigned to the same master but is inactive because its VT is inactive and the xserver is still active. But when "fake-activating" weston, it calls drmSetMaster(). With current behavior this returns "0/success" and weston thinks that it is DRM-Master, even though it is not (as the xserver is still DRM-Master). Expected behavior would be drmSetMaster() to return -EINVAL, because the xserver is still DRM-Master. This patch changes exactly that. The only way this bogus behavior would be useful is for clients to check whether their associated "drm_master" is currently the active DRM-Master. But this logic fails if no DRM-Master is currently active at all. Because then the client itself would become DRM-Master (if it is root) and this makes this whole thing useles. Also note that the second "if-condition": file_priv->minor->master != file_priv->master is always true and can be skipped. Signed-off-by: David Herrmann <dh.herrmann@googlemail.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2012-11-15 21:04:37 +08:00
if (dev->driver->master_set) {
ret = dev->driver->master_set(dev, file_priv, false);
if (unlikely(ret != 0)) {
file_priv->is_master = 0;
drm: fix returning -EINVAL on setmaster if another master is active We link every DRM "file_priv" to a "drm_master" structure. Currently, the drmSetMaster() call returns 0 when there is _any_ active master associated with the "drm_master" structure of the calling "file_priv". This means, that after drmSetMaster() we are not guaranteed to be DRM-Master and might not be able to perform mode-setting. A way to reproduce this is by starting weston with the DRM backend from within an X-console (eg., xterm). Because the xserver's "drm_master" is currently active, weston is assigned to the same master but is inactive because its VT is inactive and the xserver is still active. But when "fake-activating" weston, it calls drmSetMaster(). With current behavior this returns "0/success" and weston thinks that it is DRM-Master, even though it is not (as the xserver is still DRM-Master). Expected behavior would be drmSetMaster() to return -EINVAL, because the xserver is still DRM-Master. This patch changes exactly that. The only way this bogus behavior would be useful is for clients to check whether their associated "drm_master" is currently the active DRM-Master. But this logic fails if no DRM-Master is currently active at all. Because then the client itself would become DRM-Master (if it is root) and this makes this whole thing useles. Also note that the second "if-condition": file_priv->minor->master != file_priv->master is always true and can be skipped. Signed-off-by: David Herrmann <dh.herrmann@googlemail.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2012-11-15 21:04:37 +08:00
drm_master_put(&file_priv->minor->master);
}
}
out_unlock:
mutex_unlock(&dev->master_mutex);
return ret;
}
int drm_dropmaster_ioctl(struct drm_device *dev, void *data,
struct drm_file *file_priv)
{
int ret = -EINVAL;
mutex_lock(&dev->master_mutex);
if (!file_priv->is_master)
goto out_unlock;
if (!file_priv->minor->master)
goto out_unlock;
ret = 0;
if (dev->driver->master_drop)
dev->driver->master_drop(dev, file_priv, false);
drm_master_put(&file_priv->minor->master);
file_priv->is_master = 0;
out_unlock:
mutex_unlock(&dev->master_mutex);
return ret;
}
/*
* DRM Minors
* A DRM device can provide several char-dev interfaces on the DRM-Major. Each
* of them is represented by a drm_minor object. Depending on the capabilities
* of the device-driver, different interfaces are registered.
*
* Minors can be accessed via dev->$minor_name. This pointer is either
* NULL or a valid drm_minor pointer and stays valid as long as the device is
* valid. This means, DRM minors have the same life-time as the underlying
* device. However, this doesn't mean that the minor is active. Minors are
* registered and unregistered dynamically according to device-state.
*/
static struct drm_minor **drm_minor_get_slot(struct drm_device *dev,
unsigned int type)
{
switch (type) {
case DRM_MINOR_LEGACY:
return &dev->primary;
case DRM_MINOR_RENDER:
return &dev->render;
case DRM_MINOR_CONTROL:
return &dev->control;
default:
return NULL;
}
}
static int drm_minor_alloc(struct drm_device *dev, unsigned int type)
{
struct drm_minor *minor;
unsigned long flags;
int r;
minor = kzalloc(sizeof(*minor), GFP_KERNEL);
if (!minor)
return -ENOMEM;
minor->type = type;
minor->dev = dev;
idr_preload(GFP_KERNEL);
spin_lock_irqsave(&drm_minor_lock, flags);
r = idr_alloc(&drm_minors_idr,
NULL,
64 * type,
64 * (type + 1),
GFP_NOWAIT);
spin_unlock_irqrestore(&drm_minor_lock, flags);
idr_preload_end();
if (r < 0)
goto err_free;
minor->index = r;
minor->kdev = drm_sysfs_minor_alloc(minor);
if (IS_ERR(minor->kdev)) {
r = PTR_ERR(minor->kdev);
goto err_index;
}
*drm_minor_get_slot(dev, type) = minor;
return 0;
err_index:
spin_lock_irqsave(&drm_minor_lock, flags);
idr_remove(&drm_minors_idr, minor->index);
spin_unlock_irqrestore(&drm_minor_lock, flags);
err_free:
kfree(minor);
return r;
}
static void drm_minor_free(struct drm_device *dev, unsigned int type)
{
struct drm_minor **slot, *minor;
unsigned long flags;
slot = drm_minor_get_slot(dev, type);
minor = *slot;
if (!minor)
return;
put_device(minor->kdev);
spin_lock_irqsave(&drm_minor_lock, flags);
idr_remove(&drm_minors_idr, minor->index);
spin_unlock_irqrestore(&drm_minor_lock, flags);
kfree(minor);
*slot = NULL;
}
static int drm_minor_register(struct drm_device *dev, unsigned int type)
{
struct drm_minor *minor;
unsigned long flags;
int ret;
DRM_DEBUG("\n");
minor = *drm_minor_get_slot(dev, type);
if (!minor)
return 0;
ret = drm_debugfs_init(minor, minor->index, drm_debugfs_root);
if (ret) {
DRM_ERROR("DRM: Failed to initialize /sys/kernel/debug/dri.\n");
return ret;
}
ret = device_add(minor->kdev);
if (ret)
drm: remove procfs code, take 2 So almost two years ago I've tried to nuke the procfs code already once before: http://lists.freedesktop.org/archives/dri-devel/2011-October/015707.html The conclusion was that userspace drivers (specifically libdrm device node detection) stopped relying on procfs in 2001. But after some digging it turned out that the drmstat tool in libdrm is still using those files (but only when certain options are set). So we've decided to keep profcs. But I when I've started to dig around again what exactly this tool does I've noticed that it tries to read the "mem", "vm", and "vma" files from procfs. Now as far my git history digging shows "mem" never did anything useful (at least in the version that first showed up in upstream history in 2004) and the file was remove in commit 955b12def42e83287c1bdb1411d99451753c1391 Author: Ben Gamari <bgamari@gmail.com> Date: Tue Feb 17 20:08:49 2009 -0500 drm: Convert proc files to seq_file and introduce debugfs Which means that for over 4 years drmstat has been broken, and no one cared. In my opinion that's proof enough that no one is actually using drmstat, and so that we can savely nuke the procfs support from drm. While at it fix up the error case cleanup for debugfs in drm_get_minor. v2: Fix dates, libdrm stopped relying on procfs for drm node detection in 2001. v3: fixup compilation warning for !CONFIG_DEBUG_FS, reported by Fengguang Wu. Cc: kbuild test robot <fengguang.wu@intel.com> Cc: Dave Airlie <airlied@linux.ie> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Dave Airlie <airlied@redhat.com>
2013-08-08 21:41:34 +08:00
goto err_debugfs;
/* replace NULL with @minor so lookups will succeed from now on */
spin_lock_irqsave(&drm_minor_lock, flags);
idr_replace(&drm_minors_idr, minor, minor->index);
spin_unlock_irqrestore(&drm_minor_lock, flags);
DRM_DEBUG("new minor registered %d\n", minor->index);
return 0;
drm: remove procfs code, take 2 So almost two years ago I've tried to nuke the procfs code already once before: http://lists.freedesktop.org/archives/dri-devel/2011-October/015707.html The conclusion was that userspace drivers (specifically libdrm device node detection) stopped relying on procfs in 2001. But after some digging it turned out that the drmstat tool in libdrm is still using those files (but only when certain options are set). So we've decided to keep profcs. But I when I've started to dig around again what exactly this tool does I've noticed that it tries to read the "mem", "vm", and "vma" files from procfs. Now as far my git history digging shows "mem" never did anything useful (at least in the version that first showed up in upstream history in 2004) and the file was remove in commit 955b12def42e83287c1bdb1411d99451753c1391 Author: Ben Gamari <bgamari@gmail.com> Date: Tue Feb 17 20:08:49 2009 -0500 drm: Convert proc files to seq_file and introduce debugfs Which means that for over 4 years drmstat has been broken, and no one cared. In my opinion that's proof enough that no one is actually using drmstat, and so that we can savely nuke the procfs support from drm. While at it fix up the error case cleanup for debugfs in drm_get_minor. v2: Fix dates, libdrm stopped relying on procfs for drm node detection in 2001. v3: fixup compilation warning for !CONFIG_DEBUG_FS, reported by Fengguang Wu. Cc: kbuild test robot <fengguang.wu@intel.com> Cc: Dave Airlie <airlied@linux.ie> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Dave Airlie <airlied@redhat.com>
2013-08-08 21:41:34 +08:00
err_debugfs:
drm_debugfs_cleanup(minor);
return ret;
}
static void drm_minor_unregister(struct drm_device *dev, unsigned int type)
{
struct drm_minor *minor;
unsigned long flags;
minor = *drm_minor_get_slot(dev, type);
if (!minor || !device_is_registered(minor->kdev))
return;
/* replace @minor with NULL so lookups will fail from now on */
spin_lock_irqsave(&drm_minor_lock, flags);
idr_replace(&drm_minors_idr, NULL, minor->index);
spin_unlock_irqrestore(&drm_minor_lock, flags);
device_del(minor->kdev);
dev_set_drvdata(minor->kdev, NULL); /* safety belt */
drm_debugfs_cleanup(minor);
}
/**
* drm_minor_acquire - Acquire a DRM minor
* @minor_id: Minor ID of the DRM-minor
*
* Looks up the given minor-ID and returns the respective DRM-minor object. The
* refence-count of the underlying device is increased so you must release this
* object with drm_minor_release().
*
* As long as you hold this minor, it is guaranteed that the object and the
* minor->dev pointer will stay valid! However, the device may get unplugged and
* unregistered while you hold the minor.
*
* Returns:
* Pointer to minor-object with increased device-refcount, or PTR_ERR on
* failure.
*/
struct drm_minor *drm_minor_acquire(unsigned int minor_id)
{
struct drm_minor *minor;
unsigned long flags;
spin_lock_irqsave(&drm_minor_lock, flags);
minor = idr_find(&drm_minors_idr, minor_id);
if (minor)
drm_dev_ref(minor->dev);
spin_unlock_irqrestore(&drm_minor_lock, flags);
if (!minor) {
return ERR_PTR(-ENODEV);
} else if (drm_device_is_unplugged(minor->dev)) {
drm_dev_unref(minor->dev);
return ERR_PTR(-ENODEV);
}
return minor;
}
/**
* drm_minor_release - Release DRM minor
* @minor: Pointer to DRM minor object
*
* Release a minor that was previously acquired via drm_minor_acquire().
*/
void drm_minor_release(struct drm_minor *minor)
{
drm_dev_unref(minor->dev);
}
/**
* DOC: driver instance overview
*
* A device instance for a drm driver is represented by struct &drm_device. This
* is allocated with drm_dev_alloc(), usually from bus-specific ->probe()
* callbacks implemented by the driver. The driver then needs to initialize all
* the various subsystems for the drm device like memory management, vblank
* handling, modesetting support and intial output configuration plus obviously
* initialize all the corresponding hardware bits. An important part of this is
* also calling drm_dev_set_unique() to set the userspace-visible unique name of
* this device instance. Finally when everything is up and running and ready for
* userspace the device instance can be published using drm_dev_register().
*
* There is also deprecated support for initalizing device instances using
* bus-specific helpers and the ->load() callback. But due to
* backwards-compatibility needs the device instance have to be published too
* early, which requires unpretty global locking to make safe and is therefore
* only support for existing drivers not yet converted to the new scheme.
*
* When cleaning up a device instance everything needs to be done in reverse:
* First unpublish the device instance with drm_dev_unregister(). Then clean up
* any other resources allocated at device initialization and drop the driver's
* reference to &drm_device using drm_dev_unref().
*
* Note that the lifetime rules for &drm_device instance has still a lot of
* historical baggage. Hence use the reference counting provided by
* drm_dev_ref() and drm_dev_unref() only carefully.
*
* Also note that embedding of &drm_device is currently not (yet) supported (but
* it would be easy to add). Drivers can store driver-private data in the
* dev_priv field of &drm_device.
*/
/**
* drm_put_dev - Unregister and release a DRM device
* @dev: DRM device
*
* Called at module unload time or when a PCI device is unplugged.
*
* Cleans up all DRM device, calling drm_lastclose().
*
* Note: Use of this function is deprecated. It will eventually go away
* completely. Please use drm_dev_unregister() and drm_dev_unref() explicitly
* instead to make sure that the device isn't userspace accessible any more
* while teardown is in progress, ensuring that userspace can't access an
* inconsistent state.
*/
void drm_put_dev(struct drm_device *dev)
{
DRM_DEBUG("\n");
if (!dev) {
DRM_ERROR("cleanup called no dev\n");
return;
}
drm_dev_unregister(dev);
drm_dev_unref(dev);
}
EXPORT_SYMBOL(drm_put_dev);
void drm_unplug_dev(struct drm_device *dev)
{
/* for a USB device */
drm_minor_unregister(dev, DRM_MINOR_LEGACY);
drm_minor_unregister(dev, DRM_MINOR_RENDER);
drm_minor_unregister(dev, DRM_MINOR_CONTROL);
mutex_lock(&drm_global_mutex);
drm_device_set_unplugged(dev);
if (dev->open_count == 0) {
drm_put_dev(dev);
}
mutex_unlock(&drm_global_mutex);
}
EXPORT_SYMBOL(drm_unplug_dev);
drm: add pseudo filesystem for shared inodes Our current DRM design uses a single address_space for all users of the same DRM device. However, there is no way to create an anonymous address_space without an underlying inode. Therefore, we wait for the first ->open() callback on a registered char-dev and take-over the inode of the char-dev. This worked well so far, but has several drawbacks: - We screw with FS internals and rely on some non-obvious invariants like inode->i_mapping being the same as inode->i_data for char-devs. - We don't have any address_space prior to the first ->open() from user-space. This leads to ugly fallback code and we cannot allocate global objects early. As pointed out by Al-Viro, fs/anon_inode.c is *not* supposed to be used by drivers for anonymous inode-allocation. Therefore, this patch follows the proposed alternative solution and adds a pseudo filesystem mount-point to DRM. We can then allocate private inodes including a private address_space for each DRM device at initialization time. Note that we could use: sysfs_get_inode(sysfs_mnt->mnt_sb, drm_device->dev->kobj.sd); to get access to the underlying sysfs-inode of a "struct device" object. However, most of this information is currently hidden and it's not clear whether this address_space is suitable for driver access. Thus, unless linux allows anonymous address_space objects or driver-core provides a public inode per device, we're left with our own private internal mount point. Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
2014-01-03 21:09:47 +08:00
/*
* DRM internal mount
* We want to be able to allocate our own "struct address_space" to control
* memory-mappings in VRAM (or stolen RAM, ...). However, core MM does not allow
* stand-alone address_space objects, so we need an underlying inode. As there
* is no way to allocate an independent inode easily, we need a fake internal
* VFS mount-point.
*
* The drm_fs_inode_new() function allocates a new inode, drm_fs_inode_free()
* frees it again. You are allowed to use iget() and iput() to get references to
* the inode. But each drm_fs_inode_new() call must be paired with exactly one
* drm_fs_inode_free() call (which does not have to be the last iput()).
* We use drm_fs_inode_*() to manage our internal VFS mount-point and share it
* between multiple inode-users. You could, technically, call
* iget() + drm_fs_inode_free() directly after alloc and sometime later do an
* iput(), but this way you'd end up with a new vfsmount for each inode.
*/
static int drm_fs_cnt;
static struct vfsmount *drm_fs_mnt;
static const struct dentry_operations drm_fs_dops = {
.d_dname = simple_dname,
};
static const struct super_operations drm_fs_sops = {
.statfs = simple_statfs,
};
static struct dentry *drm_fs_mount(struct file_system_type *fs_type, int flags,
const char *dev_name, void *data)
{
return mount_pseudo(fs_type,
"drm:",
&drm_fs_sops,
&drm_fs_dops,
0x010203ff);
}
static struct file_system_type drm_fs_type = {
.name = "drm",
.owner = THIS_MODULE,
.mount = drm_fs_mount,
.kill_sb = kill_anon_super,
};
static struct inode *drm_fs_inode_new(void)
{
struct inode *inode;
int r;
r = simple_pin_fs(&drm_fs_type, &drm_fs_mnt, &drm_fs_cnt);
if (r < 0) {
DRM_ERROR("Cannot mount pseudo fs: %d\n", r);
return ERR_PTR(r);
}
inode = alloc_anon_inode(drm_fs_mnt->mnt_sb);
if (IS_ERR(inode))
simple_release_fs(&drm_fs_mnt, &drm_fs_cnt);
return inode;
}
static void drm_fs_inode_free(struct inode *inode)
{
if (inode) {
iput(inode);
simple_release_fs(&drm_fs_mnt, &drm_fs_cnt);
}
}
/**
* drm_dev_alloc - Allocate new DRM device
* @driver: DRM driver to allocate device for
* @parent: Parent device object
*
* Allocate and initialize a new DRM device. No device registration is done.
* Call drm_dev_register() to advertice the device to user space and register it
* with other core subsystems. This should be done last in the device
* initialization sequence to make sure userspace can't access an inconsistent
* state.
*
* The initial ref-count of the object is 1. Use drm_dev_ref() and
* drm_dev_unref() to take and drop further ref-counts.
*
* Note that for purely virtual devices @parent can be NULL.
*
* RETURNS:
* Pointer to new DRM device, or NULL if out of memory.
*/
struct drm_device *drm_dev_alloc(struct drm_driver *driver,
struct device *parent)
{
struct drm_device *dev;
int ret;
dev = kzalloc(sizeof(*dev), GFP_KERNEL);
if (!dev)
return NULL;
kref_init(&dev->ref);
dev->dev = parent;
dev->driver = driver;
INIT_LIST_HEAD(&dev->filelist);
INIT_LIST_HEAD(&dev->ctxlist);
INIT_LIST_HEAD(&dev->vmalist);
INIT_LIST_HEAD(&dev->maplist);
INIT_LIST_HEAD(&dev->vblank_event_list);
spin_lock_init(&dev->buf_lock);
spin_lock_init(&dev->event_lock);
mutex_init(&dev->struct_mutex);
mutex_init(&dev->ctxlist_mutex);
mutex_init(&dev->master_mutex);
dev->anon_inode = drm_fs_inode_new();
if (IS_ERR(dev->anon_inode)) {
ret = PTR_ERR(dev->anon_inode);
DRM_ERROR("Cannot allocate anonymous inode: %d\n", ret);
goto err_free;
}
if (drm_core_check_feature(dev, DRIVER_MODESET)) {
ret = drm_minor_alloc(dev, DRM_MINOR_CONTROL);
if (ret)
goto err_minors;
WARN_ON(driver->suspend || driver->resume);
}
if (drm_core_check_feature(dev, DRIVER_RENDER)) {
ret = drm_minor_alloc(dev, DRM_MINOR_RENDER);
if (ret)
goto err_minors;
}
ret = drm_minor_alloc(dev, DRM_MINOR_LEGACY);
if (ret)
goto err_minors;
if (drm_ht_create(&dev->map_hash, 12))
goto err_minors;
drm_legacy_ctxbitmap_init(dev);
if (drm_core_check_feature(dev, DRIVER_GEM)) {
ret = drm_gem_init(dev);
if (ret) {
DRM_ERROR("Cannot initialize graphics execution manager (GEM)\n");
goto err_ctxbitmap;
}
}
if (parent) {
ret = drm_dev_set_unique(dev, dev_name(parent));
if (ret)
goto err_setunique;
}
return dev;
err_setunique:
if (drm_core_check_feature(dev, DRIVER_GEM))
drm_gem_destroy(dev);
err_ctxbitmap:
drm_legacy_ctxbitmap_cleanup(dev);
drm_ht_remove(&dev->map_hash);
err_minors:
drm_minor_free(dev, DRM_MINOR_LEGACY);
drm_minor_free(dev, DRM_MINOR_RENDER);
drm_minor_free(dev, DRM_MINOR_CONTROL);
drm_fs_inode_free(dev->anon_inode);
err_free:
mutex_destroy(&dev->master_mutex);
kfree(dev);
return NULL;
}
EXPORT_SYMBOL(drm_dev_alloc);
static void drm_dev_release(struct kref *ref)
{
struct drm_device *dev = container_of(ref, struct drm_device, ref);
if (drm_core_check_feature(dev, DRIVER_GEM))
drm_gem_destroy(dev);
drm_legacy_ctxbitmap_cleanup(dev);
drm_ht_remove(&dev->map_hash);
drm_fs_inode_free(dev->anon_inode);
drm_minor_free(dev, DRM_MINOR_LEGACY);
drm_minor_free(dev, DRM_MINOR_RENDER);
drm_minor_free(dev, DRM_MINOR_CONTROL);
mutex_destroy(&dev->master_mutex);
kfree(dev->unique);
kfree(dev);
}
/**
* drm_dev_ref - Take reference of a DRM device
* @dev: device to take reference of or NULL
*
* This increases the ref-count of @dev by one. You *must* already own a
* reference when calling this. Use drm_dev_unref() to drop this reference
* again.
*
* This function never fails. However, this function does not provide *any*
* guarantee whether the device is alive or running. It only provides a
* reference to the object and the memory associated with it.
*/
void drm_dev_ref(struct drm_device *dev)
{
if (dev)
kref_get(&dev->ref);
}
EXPORT_SYMBOL(drm_dev_ref);
/**
* drm_dev_unref - Drop reference of a DRM device
* @dev: device to drop reference of or NULL
*
* This decreases the ref-count of @dev by one. The device is destroyed if the
* ref-count drops to zero.
*/
void drm_dev_unref(struct drm_device *dev)
{
if (dev)
kref_put(&dev->ref, drm_dev_release);
}
EXPORT_SYMBOL(drm_dev_unref);
/**
* drm_dev_register - Register DRM device
* @dev: Device to register
* @flags: Flags passed to the driver's .load() function
*
* Register the DRM device @dev with the system, advertise device to user-space
* and start normal device operation. @dev must be allocated via drm_dev_alloc()
* previously.
*
* Never call this twice on any device!
*
* NOTE: To ensure backward compatibility with existing drivers method this
* function calls the ->load() method after registering the device nodes,
* creating race conditions. Usage of the ->load() methods is therefore
* deprecated, drivers must perform all initialization before calling
* drm_dev_register().
*
* RETURNS:
* 0 on success, negative error code on failure.
*/
int drm_dev_register(struct drm_device *dev, unsigned long flags)
{
int ret;
mutex_lock(&drm_global_mutex);
ret = drm_minor_register(dev, DRM_MINOR_CONTROL);
if (ret)
goto err_minors;
ret = drm_minor_register(dev, DRM_MINOR_RENDER);
if (ret)
goto err_minors;
ret = drm_minor_register(dev, DRM_MINOR_LEGACY);
if (ret)
goto err_minors;
if (dev->driver->load) {
ret = dev->driver->load(dev, flags);
if (ret)
goto err_minors;
}
ret = 0;
goto out_unlock;
err_minors:
drm_minor_unregister(dev, DRM_MINOR_LEGACY);
drm_minor_unregister(dev, DRM_MINOR_RENDER);
drm_minor_unregister(dev, DRM_MINOR_CONTROL);
out_unlock:
mutex_unlock(&drm_global_mutex);
return ret;
}
EXPORT_SYMBOL(drm_dev_register);
/**
* drm_dev_unregister - Unregister DRM device
* @dev: Device to unregister
*
* Unregister the DRM device from the system. This does the reverse of
* drm_dev_register() but does not deallocate the device. The caller must call
* drm_dev_unref() to drop their final reference.
*
* This should be called first in the device teardown code to make sure
* userspace can't access the device instance any more.
*/
void drm_dev_unregister(struct drm_device *dev)
{
struct drm_map_list *r_list, *list_temp;
drm_lastclose(dev);
if (dev->driver->unload)
dev->driver->unload(dev);
if (dev->agp)
drm_pci_agp_destroy(dev);
drm_vblank_cleanup(dev);
list_for_each_entry_safe(r_list, list_temp, &dev->maplist, head)
drm_legacy_rmmap(dev, r_list->map);
drm_minor_unregister(dev, DRM_MINOR_LEGACY);
drm_minor_unregister(dev, DRM_MINOR_RENDER);
drm_minor_unregister(dev, DRM_MINOR_CONTROL);
}
EXPORT_SYMBOL(drm_dev_unregister);
/**
* drm_dev_set_unique - Set the unique name of a DRM device
* @dev: device of which to set the unique name
* @name: unique name
*
* Sets the unique name of a DRM device using the specified string. Drivers
* can use this at driver probe time if the unique name of the devices they
* drive is static.
*
* Return: 0 on success or a negative error code on failure.
*/
int drm_dev_set_unique(struct drm_device *dev, const char *name)
{
kfree(dev->unique);
dev->unique = kstrdup(name, GFP_KERNEL);
return dev->unique ? 0 : -ENOMEM;
}
EXPORT_SYMBOL(drm_dev_set_unique);
/*
* DRM Core
* The DRM core module initializes all global DRM objects and makes them
* available to drivers. Once setup, drivers can probe their respective
* devices.
* Currently, core management includes:
* - The "DRM-Global" key/value database
* - Global ID management for connectors
* - DRM major number allocation
* - DRM minor management
* - DRM sysfs class
* - DRM debugfs root
*
* Furthermore, the DRM core provides dynamic char-dev lookups. For each
* interface registered on a DRM device, you can request minor numbers from DRM
* core. DRM core takes care of major-number management and char-dev
* registration. A stub ->open() callback forwards any open() requests to the
* registered minor.
*/
static int drm_stub_open(struct inode *inode, struct file *filp)
{
const struct file_operations *new_fops;
struct drm_minor *minor;
int err;
DRM_DEBUG("\n");
mutex_lock(&drm_global_mutex);
minor = drm_minor_acquire(iminor(inode));
if (IS_ERR(minor)) {
err = PTR_ERR(minor);
goto out_unlock;
}
new_fops = fops_get(minor->dev->driver->fops);
if (!new_fops) {
err = -ENODEV;
goto out_release;
}
replace_fops(filp, new_fops);
if (filp->f_op->open)
err = filp->f_op->open(inode, filp);
else
err = 0;
out_release:
drm_minor_release(minor);
out_unlock:
mutex_unlock(&drm_global_mutex);
return err;
}
static const struct file_operations drm_stub_fops = {
.owner = THIS_MODULE,
.open = drm_stub_open,
.llseek = noop_llseek,
};
static int __init drm_core_init(void)
{
int ret = -ENOMEM;
drm_global_init();
drm_connector_ida_init();
idr_init(&drm_minors_idr);
if (register_chrdev(DRM_MAJOR, "drm", &drm_stub_fops))
goto err_p1;
ret = drm_sysfs_init();
if (ret < 0) {
printk(KERN_ERR "DRM: Error creating drm class.\n");
goto err_p2;
}
drm_debugfs_root = debugfs_create_dir("dri", NULL);
if (!drm_debugfs_root) {
DRM_ERROR("Cannot create /sys/kernel/debug/dri\n");
ret = -1;
goto err_p3;
}
DRM_INFO("Initialized %s %d.%d.%d %s\n",
CORE_NAME, CORE_MAJOR, CORE_MINOR, CORE_PATCHLEVEL, CORE_DATE);
return 0;
err_p3:
drm_sysfs_destroy();
err_p2:
unregister_chrdev(DRM_MAJOR, "drm");
idr_destroy(&drm_minors_idr);
err_p1:
return ret;
}
static void __exit drm_core_exit(void)
{
debugfs_remove(drm_debugfs_root);
drm_sysfs_destroy();
unregister_chrdev(DRM_MAJOR, "drm");
drm_connector_ida_destroy();
idr_destroy(&drm_minors_idr);
}
module_init(drm_core_init);
module_exit(drm_core_exit);