linux_dsm_epyc7002/drivers/gpu/drm/drm_fops.c

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/*
* \file drm_fops.c
* File operations for DRM
*
* \author Rickard E. (Rik) Faith <faith@valinux.com>
* \author Daryll Strauss <daryll@valinux.com>
* \author Gareth Hughes <gareth@valinux.com>
*/
/*
* Created: Mon Jan 4 08:58:31 1999 by faith@valinux.com
*
* Copyright 1999 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.
*/
#include <drm/drmP.h>
#include <linux/poll.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 15:04:11 +07:00
#include <linux/slab.h>
#include <linux/module.h>
#include "drm_legacy.h"
#include "drm_internal.h"
#include "drm_crtc_internal.h"
/* from BKL pushdown */
DEFINE_MUTEX(drm_global_mutex);
/**
* DOC: file operations
*
* Drivers must define the file operations structure that forms the DRM
* userspace API entry point, even though most of those operations are
* implemented in the DRM core. The mandatory functions are drm_open(),
* drm_read(), drm_ioctl() and drm_compat_ioctl if CONFIG_COMPAT is enabled.
* Drivers which implement private ioctls that require 32/64 bit compatibility
* support must provided their onw .compat_ioctl() handler that processes
* private ioctls and calls drm_compat_ioctl() for core ioctls.
*
* In addition drm_read() and drm_poll() provide support for DRM events. DRM
* events are a generic and extensible means to send asynchronous events to
* userspace through the file descriptor. They are used to send vblank event and
* page flip completions by the KMS API. But drivers can also use it for their
* own needs, e.g. to signal completion of rendering.
*
* The memory mapping implementation will vary depending on how the driver
* manages memory. Legacy drivers will use the deprecated drm_legacy_mmap()
* function, modern drivers should use one of the provided memory-manager
* specific implementations. For GEM-based drivers this is drm_gem_mmap().
*
* No other file operations are supported by the DRM userspace API. Overall the
* following is an example #file_operations structure::
*
* static const example_drm_fops = {
* .owner = THIS_MODULE,
* .open = drm_open,
* .release = drm_release,
* .unlocked_ioctl = drm_ioctl,
* #ifdef CONFIG_COMPAT
* .compat_ioctl = drm_compat_ioctl,
* #endif
* .poll = drm_poll,
* .read = drm_read,
* .llseek = no_llseek,
* .mmap = drm_gem_mmap,
* };
*/
static int drm_open_helper(struct file *filp, struct drm_minor *minor);
static int drm_setup(struct drm_device * dev)
{
int ret;
if (dev->driver->firstopen &&
!drm_core_check_feature(dev, DRIVER_MODESET)) {
ret = dev->driver->firstopen(dev);
if (ret != 0)
return ret;
}
ret = drm_legacy_dma_setup(dev);
if (ret < 0)
return ret;
DRM_DEBUG("\n");
return 0;
}
/**
* drm_open - open method for DRM file
* @inode: device inode
* @filp: file pointer.
*
* This function must be used by drivers as their .open() #file_operations
* method. It looks up the correct DRM device and instantiates all the per-file
* resources for it.
*
* RETURNS:
*
* 0 on success or negative errno value on falure.
*/
int drm_open(struct inode *inode, struct file *filp)
{
struct drm_device *dev;
struct drm_minor *minor;
int retcode;
int need_setup = 0;
minor = drm_minor_acquire(iminor(inode));
if (IS_ERR(minor))
return PTR_ERR(minor);
dev = minor->dev;
if (!dev->open_count++)
need_setup = 1;
/* share address_space across all char-devs of a single device */
filp->f_mapping = dev->anon_inode->i_mapping;
retcode = drm_open_helper(filp, minor);
if (retcode)
goto err_undo;
if (need_setup) {
retcode = drm_setup(dev);
if (retcode)
goto err_undo;
}
return 0;
err_undo:
dev->open_count--;
drm_minor_release(minor);
return retcode;
}
EXPORT_SYMBOL(drm_open);
/*
* Check whether DRI will run on this CPU.
*
* \return non-zero if the DRI will run on this CPU, or zero otherwise.
*/
static int drm_cpu_valid(void)
{
#if defined(__sparc__) && !defined(__sparc_v9__)
return 0; /* No cmpxchg before v9 sparc. */
#endif
return 1;
}
/*
* Called whenever a process opens /dev/drm.
*
* \param filp file pointer.
* \param minor acquired minor-object.
* \return zero on success or a negative number on failure.
*
* Creates and initializes a drm_file structure for the file private data in \p
* filp and add it into the double linked list in \p dev.
*/
static int drm_open_helper(struct file *filp, struct drm_minor *minor)
{
struct drm_device *dev = minor->dev;
struct drm_file *priv;
int ret;
if (filp->f_flags & O_EXCL)
return -EBUSY; /* No exclusive opens */
if (!drm_cpu_valid())
return -EINVAL;
if (dev->switch_power_state != DRM_SWITCH_POWER_ON && dev->switch_power_state != DRM_SWITCH_POWER_DYNAMIC_OFF)
return -EINVAL;
DRM_DEBUG("pid = %d, minor = %d\n", task_pid_nr(current), minor->index);
priv = kzalloc(sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
filp->private_data = priv;
priv->filp = filp;
priv->uid = current_euid();
priv->pid = get_pid(task_pid(current));
priv->minor = minor;
/* for compatibility root is always authenticated */
priv->authenticated = capable(CAP_SYS_ADMIN);
priv->lock_count = 0;
INIT_LIST_HEAD(&priv->lhead);
INIT_LIST_HEAD(&priv->fbs);
drm: revamp locking around fb creation/destruction Well, at least step 1. The goal here is that framebuffer objects can survive outside of the mode_config lock, with just a reference held as protection. The first step to get there is to introduce a special fb_lock which protects fb lookup, creation and destruction, to make them appear atomic. This new fb_lock can nest within the mode_config lock. But the idea is (once the reference counting part is completed) that we only quickly take that fb_lock to lookup a framebuffer and grab a reference, without any other locks involved. vmwgfx is the only driver which does framebuffer lookups itself, also wrap those calls to drm_mode_object_find with the new lock. Also protect the fb_list walking in i915 and omapdrm with the new lock. As a slight complication there's also the list of user-created fbs attached to the file private. The problem now is that at fclose() time we need to walk that list, eventually do a modeset call to remove the fb from active usage (and are required to be able to take the mode_config lock), but in the end we need to grab the new fb_lock to remove the fb from the list. The easiest solution is to add another mutex to protect this per-file list. Currently that new fbs_lock nests within the modeset locks and so appears redudant. But later patches will switch around this sequence so that taking the modeset locks in the fb destruction path is optional in the fastpath. Ultimately the goal is that addfb and rmfb do not require the mode_config lock, since otherwise they have the potential to introduce stalls in the pageflip sequence of a compositor (if the compositor e.g. switches to a fullscreen client or if it enables a plane). But that requires a few more steps and hoops to jump through. Note that framebuffer creation/destruction is now double-protected - once by the fb_lock and in parts by the idr_lock. The later would be unnecessariy if framebuffers would have their own idr allocator. But that's material for another patch (series). v2: Properly initialize the fb->filp_head list in _init, otherwise the newly added WARN to check whether the fb isn't on a fpriv list any more will fail for driver-private objects. v3: Fixup two error-case unlock bugs spotted by Richard Wilbur. Reviewed-by: Rob Clark <rob@ti.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-12-11 03:19:18 +07:00
mutex_init(&priv->fbs_lock);
INIT_LIST_HEAD(&priv->blobs);
INIT_LIST_HEAD(&priv->pending_event_list);
INIT_LIST_HEAD(&priv->event_list);
init_waitqueue_head(&priv->event_wait);
priv->event_space = 4096; /* set aside 4k for event buffer */
mutex_init(&priv->event_read_lock);
if (drm_core_check_feature(dev, DRIVER_GEM))
drm_gem_open(dev, priv);
if (drm_core_check_feature(dev, DRIVER_PRIME))
drm_prime_init_file_private(&priv->prime);
if (dev->driver->open) {
ret = dev->driver->open(dev, priv);
if (ret < 0)
goto out_prime_destroy;
}
if (drm_is_primary_client(priv)) {
ret = drm_master_open(priv);
if (ret)
goto out_close;
}
mutex_lock(&dev->filelist_mutex);
list_add(&priv->lhead, &dev->filelist);
mutex_unlock(&dev->filelist_mutex);
#ifdef __alpha__
/*
* Default the hose
*/
if (!dev->hose) {
struct pci_dev *pci_dev;
pci_dev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, NULL);
if (pci_dev) {
dev->hose = pci_dev->sysdata;
pci_dev_put(pci_dev);
}
if (!dev->hose) {
struct pci_bus *b = list_entry(pci_root_buses.next,
struct pci_bus, node);
if (b)
dev->hose = b->sysdata;
}
}
#endif
return 0;
out_close:
if (dev->driver->postclose)
dev->driver->postclose(dev, priv);
out_prime_destroy:
if (drm_core_check_feature(dev, DRIVER_PRIME))
drm_prime_destroy_file_private(&priv->prime);
if (drm_core_check_feature(dev, DRIVER_GEM))
drm_gem_release(dev, priv);
put_pid(priv->pid);
kfree(priv);
filp->private_data = NULL;
return ret;
}
static void drm_events_release(struct drm_file *file_priv)
{
struct drm_device *dev = file_priv->minor->dev;
struct drm_pending_event *e, *et;
unsigned long flags;
spin_lock_irqsave(&dev->event_lock, flags);
/* Unlink pending events */
list_for_each_entry_safe(e, et, &file_priv->pending_event_list,
pending_link) {
list_del(&e->pending_link);
e->file_priv = NULL;
}
/* Remove unconsumed events */
list_for_each_entry_safe(e, et, &file_priv->event_list, link) {
list_del(&e->link);
kfree(e);
}
spin_unlock_irqrestore(&dev->event_lock, flags);
}
/*
* drm_legacy_dev_reinit
*
* Reinitializes a legacy/ums drm device in it's lastclose function.
*/
static void drm_legacy_dev_reinit(struct drm_device *dev)
{
if (dev->irq_enabled)
drm_irq_uninstall(dev);
mutex_lock(&dev->struct_mutex);
drm_legacy_agp_clear(dev);
drm_legacy_sg_cleanup(dev);
drm_legacy_vma_flush(dev);
drm_legacy_dma_takedown(dev);
mutex_unlock(&dev->struct_mutex);
dev->sigdata.lock = NULL;
dev->context_flag = 0;
dev->last_context = 0;
dev->if_version = 0;
DRM_DEBUG("lastclose completed\n");
}
/*
* Take down the DRM device.
*
* \param dev DRM device structure.
*
* Frees every resource in \p dev.
*
* \sa drm_device
*/
void drm_lastclose(struct drm_device * dev)
{
DRM_DEBUG("\n");
if (dev->driver->lastclose)
dev->driver->lastclose(dev);
DRM_DEBUG("driver lastclose completed\n");
if (!drm_core_check_feature(dev, DRIVER_MODESET))
drm_legacy_dev_reinit(dev);
}
/**
* drm_release - release method for DRM file
* @inode: device inode
* @filp: file pointer.
*
* This function must be used by drivers as their .release() #file_operations
* method. It frees any resources associated with the open file, and if this is
* the last open file for the DRM device also proceeds to call drm_lastclose().
*
* RETURNS:
*
* Always succeeds and returns 0.
*/
int drm_release(struct inode *inode, struct file *filp)
{
struct drm_file *file_priv = filp->private_data;
struct drm_minor *minor = file_priv->minor;
struct drm_device *dev = minor->dev;
mutex_lock(&drm_global_mutex);
DRM_DEBUG("open_count = %d\n", dev->open_count);
mutex_lock(&dev->filelist_mutex);
drm: Unlink dead file_priv from list of active files first In order to prevent external observers walking the list of open DRM files from seeing an invalid drm_file_private in the process of being torndown, the first operation we need to take is to unlink the drm_file_private from that list. general protection fault: 0000 [#1] PREEMPT SMP Modules linked in: i915 i2c_algo_bit drm_kms_helper drm lpc_ich mfd_core nls_iso8859_1 i2c_hid video hid_generic usbhid hid e1000e ahci ptp libahci pps_core CPU: 3 PID: 8220 Comm: cat Not tainted 3.16.0-rc6+ #4 Hardware name: Intel Corporation Shark Bay Client platform/WhiteTip Mountain 1, BIOS HSWLPTU1.86C.0119.R00.1303230105 03/23/2013 task: ffff8800219642c0 ti: ffff880047024000 task.ti: ffff880047024000 RIP: 0010:[<ffffffffa0137c70>] [<ffffffffa0137c70>] per_file_stats+0x110/0x160 [i915] RSP: 0018:ffff880047027d48 EFLAGS: 00010246 RAX: 6b6b6b6b6b6b6b6b RBX: ffff880047027e30 RCX: 0000000000000000 RDX: 0000000000000001 RSI: 0000000000000000 RDI: ffff88003a05cd00 RBP: ffff880047027d58 R08: 0000000000000001 R09: 0000000000000000 R10: ffff8800219642c0 R11: 0000000000000000 R12: ffff88003a05cd00 R13: 0000000000000000 R14: ffff88003a05cd00 R15: ffff880047027d88 FS: 00007f5f73a13740(0000) GS:ffff88014e380000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000023ff038 CR3: 0000000021a4b000 CR4: 00000000001407e0 Stack: 0000000000000001 000000000000ffff ffff880047027dc8 ffffffff813438e4 ffff880047027e30 ffffffffa0137b60 ffff880021a8af58 ffff880021a8f1a0 ffff8800a2061fb0 ffff8800a2062048 ffff8800a2061fb0 ffff8800a1e23478 Call Trace: [<ffffffff813438e4>] idr_for_each+0xf4/0x180 [<ffffffffa0137b60>] ? i915_gem_stolen_list_info+0x1f0/0x1f0 [i915] [<ffffffffa013a17a>] i915_gem_object_info+0x5ca/0x6a0 [i915] [<ffffffff81193ec5>] seq_read+0xf5/0x3a0 [<ffffffff8116d950>] vfs_read+0x90/0x150 [<ffffffff8116e509>] SyS_read+0x49/0xb0 [<ffffffff815d8622>] tracesys+0xd0/0xd5 Code: 01 00 00 49 39 84 24 08 01 00 00 74 55 49 8b 84 24 b8 00 00 00 48 01 43 18 31 c0 5b 41 5c 5d c3 0f 1f 00 49 8b 44 24 08 4c 89 e7 <48> 8b 70 28 48 81 c6 48 80 00 00 e8 80 14 01 00 84 c0 74 bc 49 RIP [<ffffffffa0137c70>] per_file_stats+0x110/0x160 [i915] RSP <ffff880047027d48> Reported-by: "Ursulin, Tvrtko" <tvrtko.ursulin@intel.com> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=81712 Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: "Ursulin, Tvrtko" <tvrtko.ursulin@intel.com> Reviewed-by: David Herrmann <dh.herrmann@gmail.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2014-07-24 20:23:10 +07:00
list_del(&file_priv->lhead);
mutex_unlock(&dev->filelist_mutex);
if (dev->driver->preclose)
dev->driver->preclose(dev, file_priv);
/* ========================================================
* Begin inline drm_release
*/
DRM_DEBUG("pid = %d, device = 0x%lx, open_count = %d\n",
task_pid_nr(current),
(long)old_encode_dev(file_priv->minor->kdev->devt),
dev->open_count);
if (!drm_core_check_feature(dev, DRIVER_MODESET))
drm_legacy_lock_release(dev, filp);
if (drm_core_check_feature(dev, DRIVER_HAVE_DMA))
drm_legacy_reclaim_buffers(dev, file_priv);
drm_events_release(file_priv);
if (drm_core_check_feature(dev, DRIVER_MODESET)) {
drm_fb_release(file_priv);
drm_property_destroy_user_blobs(dev, file_priv);
}
if (drm_core_check_feature(dev, DRIVER_GEM))
drm_gem_release(dev, file_priv);
drm_legacy_ctxbitmap_flush(dev, file_priv);
if (drm_is_primary_client(file_priv))
drm_master_release(file_priv);
if (dev->driver->postclose)
dev->driver->postclose(dev, file_priv);
if (drm_core_check_feature(dev, DRIVER_PRIME))
drm_prime_destroy_file_private(&file_priv->prime);
WARN_ON(!list_empty(&file_priv->event_list));
put_pid(file_priv->pid);
kfree(file_priv);
/* ========================================================
* End inline drm_release
*/
if (!--dev->open_count) {
drm_lastclose(dev);
if (drm_device_is_unplugged(dev))
drm_put_dev(dev);
}
mutex_unlock(&drm_global_mutex);
drm_minor_release(minor);
return 0;
}
EXPORT_SYMBOL(drm_release);
/**
* drm_read - read method for DRM file
* @filp: file pointer
* @buffer: userspace destination pointer for the read
* @count: count in bytes to read
* @offset: offset to read
*
* This function must be used by drivers as their .read() #file_operations
* method iff they use DRM events for asynchronous signalling to userspace.
* Since events are used by the KMS API for vblank and page flip completion this
* means all modern display drivers must use it.
*
* @offset is ignore, DRM events are read like a pipe. Therefore drivers also
* must set the .llseek() #file_operation to no_llseek(). Polling support is
* provided by drm_poll().
*
* This function will only ever read a full event. Therefore userspace must
* supply a big enough buffer to fit any event to ensure forward progress. Since
* the maximum event space is currently 4K it's recommended to just use that for
* safety.
*
* RETURNS:
*
* Number of bytes read (always aligned to full events, and can be 0) or a
* negative error code on failure.
*/
ssize_t drm_read(struct file *filp, char __user *buffer,
size_t count, loff_t *offset)
{
struct drm_file *file_priv = filp->private_data;
struct drm_device *dev = file_priv->minor->dev;
ssize_t ret;
if (!access_ok(VERIFY_WRITE, buffer, count))
return -EFAULT;
ret = mutex_lock_interruptible(&file_priv->event_read_lock);
if (ret)
return ret;
for (;;) {
struct drm_pending_event *e = NULL;
spin_lock_irq(&dev->event_lock);
if (!list_empty(&file_priv->event_list)) {
e = list_first_entry(&file_priv->event_list,
struct drm_pending_event, link);
file_priv->event_space += e->event->length;
list_del(&e->link);
}
spin_unlock_irq(&dev->event_lock);
if (e == NULL) {
if (ret)
break;
if (filp->f_flags & O_NONBLOCK) {
ret = -EAGAIN;
break;
}
mutex_unlock(&file_priv->event_read_lock);
ret = wait_event_interruptible(file_priv->event_wait,
!list_empty(&file_priv->event_list));
if (ret >= 0)
ret = mutex_lock_interruptible(&file_priv->event_read_lock);
if (ret)
return ret;
} else {
unsigned length = e->event->length;
if (length > count - ret) {
put_back_event:
spin_lock_irq(&dev->event_lock);
file_priv->event_space -= length;
list_add(&e->link, &file_priv->event_list);
spin_unlock_irq(&dev->event_lock);
break;
}
if (copy_to_user(buffer + ret, e->event, length)) {
if (ret == 0)
ret = -EFAULT;
goto put_back_event;
}
ret += length;
kfree(e);
}
}
mutex_unlock(&file_priv->event_read_lock);
return ret;
}
EXPORT_SYMBOL(drm_read);
/**
* drm_poll - poll method for DRM file
* @filp: file pointer
* @wait: poll waiter table
*
* This function must be used by drivers as their .read() #file_operations
* method iff they use DRM events for asynchronous signalling to userspace.
* Since events are used by the KMS API for vblank and page flip completion this
* means all modern display drivers must use it.
*
* See also drm_read().
*
* RETURNS:
*
* Mask of POLL flags indicating the current status of the file.
*/
unsigned int drm_poll(struct file *filp, struct poll_table_struct *wait)
{
struct drm_file *file_priv = filp->private_data;
unsigned int mask = 0;
poll_wait(filp, &file_priv->event_wait, wait);
if (!list_empty(&file_priv->event_list))
mask |= POLLIN | POLLRDNORM;
return mask;
}
EXPORT_SYMBOL(drm_poll);
/**
* drm_event_reserve_init_locked - init a DRM event and reserve space for it
* @dev: DRM device
* @file_priv: DRM file private data
* @p: tracking structure for the pending event
* @e: actual event data to deliver to userspace
*
* This function prepares the passed in event for eventual delivery. If the event
* doesn't get delivered (because the IOCTL fails later on, before queuing up
* anything) then the even must be cancelled and freed using
* drm_event_cancel_free(). Successfully initialized events should be sent out
* using drm_send_event() or drm_send_event_locked() to signal completion of the
* asynchronous event to userspace.
*
* If callers embedded @p into a larger structure it must be allocated with
* kmalloc and @p must be the first member element.
*
* This is the locked version of drm_event_reserve_init() for callers which
* already hold dev->event_lock.
*
* RETURNS:
*
* 0 on success or a negative error code on failure.
*/
int drm_event_reserve_init_locked(struct drm_device *dev,
struct drm_file *file_priv,
struct drm_pending_event *p,
struct drm_event *e)
{
if (file_priv->event_space < e->length)
return -ENOMEM;
file_priv->event_space -= e->length;
p->event = e;
list_add(&p->pending_link, &file_priv->pending_event_list);
p->file_priv = file_priv;
return 0;
}
EXPORT_SYMBOL(drm_event_reserve_init_locked);
/**
* drm_event_reserve_init - init a DRM event and reserve space for it
* @dev: DRM device
* @file_priv: DRM file private data
* @p: tracking structure for the pending event
* @e: actual event data to deliver to userspace
*
* This function prepares the passed in event for eventual delivery. If the event
* doesn't get delivered (because the IOCTL fails later on, before queuing up
* anything) then the even must be cancelled and freed using
* drm_event_cancel_free(). Successfully initialized events should be sent out
* using drm_send_event() or drm_send_event_locked() to signal completion of the
* asynchronous event to userspace.
*
* If callers embedded @p into a larger structure it must be allocated with
* kmalloc and @p must be the first member element.
*
* Callers which already hold dev->event_lock should use
* drm_event_reserve_init() instead.
*
* RETURNS:
*
* 0 on success or a negative error code on failure.
*/
int drm_event_reserve_init(struct drm_device *dev,
struct drm_file *file_priv,
struct drm_pending_event *p,
struct drm_event *e)
{
unsigned long flags;
int ret;
spin_lock_irqsave(&dev->event_lock, flags);
ret = drm_event_reserve_init_locked(dev, file_priv, p, e);
spin_unlock_irqrestore(&dev->event_lock, flags);
return ret;
}
EXPORT_SYMBOL(drm_event_reserve_init);
/**
* drm_event_cancel_free - free a DRM event and release it's space
* @dev: DRM device
* @p: tracking structure for the pending event
*
* This function frees the event @p initialized with drm_event_reserve_init()
* and releases any allocated space.
*/
void drm_event_cancel_free(struct drm_device *dev,
struct drm_pending_event *p)
{
unsigned long flags;
spin_lock_irqsave(&dev->event_lock, flags);
if (p->file_priv) {
p->file_priv->event_space += p->event->length;
list_del(&p->pending_link);
}
spin_unlock_irqrestore(&dev->event_lock, flags);
kfree(p);
}
EXPORT_SYMBOL(drm_event_cancel_free);
/**
* drm_send_event_locked - send DRM event to file descriptor
* @dev: DRM device
* @e: DRM event to deliver
*
* This function sends the event @e, initialized with drm_event_reserve_init(),
* to its associated userspace DRM file. Callers must already hold
* dev->event_lock, see drm_send_event() for the unlocked version.
*
* Note that the core will take care of unlinking and disarming events when the
* corresponding DRM file is closed. Drivers need not worry about whether the
* DRM file for this event still exists and can call this function upon
* completion of the asynchronous work unconditionally.
*/
void drm_send_event_locked(struct drm_device *dev, struct drm_pending_event *e)
{
assert_spin_locked(&dev->event_lock);
if (e->completion) {
/* ->completion might disappear as soon as it signalled. */
complete_all(e->completion);
e->completion = NULL;
}
if (e->fence) {
fence_signal(e->fence);
fence_put(e->fence);
}
if (!e->file_priv) {
kfree(e);
return;
}
list_del(&e->pending_link);
list_add_tail(&e->link,
&e->file_priv->event_list);
wake_up_interruptible(&e->file_priv->event_wait);
}
EXPORT_SYMBOL(drm_send_event_locked);
/**
* drm_send_event - send DRM event to file descriptor
* @dev: DRM device
* @e: DRM event to deliver
*
* This function sends the event @e, initialized with drm_event_reserve_init(),
* to its associated userspace DRM file. This function acquires dev->event_lock,
* see drm_send_event_locked() for callers which already hold this lock.
*
* Note that the core will take care of unlinking and disarming events when the
* corresponding DRM file is closed. Drivers need not worry about whether the
* DRM file for this event still exists and can call this function upon
* completion of the asynchronous work unconditionally.
*/
void drm_send_event(struct drm_device *dev, struct drm_pending_event *e)
{
unsigned long irqflags;
spin_lock_irqsave(&dev->event_lock, irqflags);
drm_send_event_locked(dev, e);
spin_unlock_irqrestore(&dev->event_lock, irqflags);
}
EXPORT_SYMBOL(drm_send_event);