drm/src/drm_fops.c

/*
 * Copyright (c) 2006, 2013, Oracle and/or its affiliates. All rights reserved.
 */

/**
 * \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.
 * Copyright (c) 2009, 2013, Intel Corporation.
 * 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 "drmP.h"

static int drm_open_helper(struct drm_minor *minor,
            int clone_id, int flags, cred_t *credp);

static __inline__ int drm_device_is_agp(struct drm_device *dev)
{
    if (drm_core_check_feature(dev, DRIVER_USE_PLATFORM_DEVICE))
        return 0;
    if (dev->driver->device_is_agp != NULL) {
        int err = (*dev->driver->device_is_agp) (dev);

        if (err != 2) {
            return err;
        }
    }

    return pci_find_capability(dev->pdev, PCI_CAP_ID_AGP);
}

static int drm_setup(struct drm_device * dev)
{
    int i;
    int ret;
    static bool first_call = true;

    if (first_call) {
        /* OSOL_drm: moved from drm_fill_in_dev */
        if (drm_core_has_AGP(dev)) {
            if (drm_device_is_agp(dev))
                dev->agp = drm_agp_init(dev);
            if (drm_core_check_feature(dev, DRIVER_REQUIRE_AGP)
                && (dev->agp == NULL)) {
                DRM_ERROR("Cannot initialize the agpgart module.\n");
                return -EINVAL;
            }
        }
    }

    if (dev->driver->firstopen) {
        ret = dev->driver->firstopen(dev);
        if (ret != 0)
            return ret;
    }

    if (first_call) {
        /* OSOL_drm: moved from drm_get_dev */
        /* setup the grouping for the legacy output */
        if (drm_core_check_feature(dev, DRIVER_MODESET)) {
            ret = drm_mode_group_init_legacy_group(dev, &dev->primary->mode_group);
            if (ret)
                return ret;
        }
    }

    atomic_set(&dev->ioctl_count, 0);

    if (drm_core_check_feature(dev, DRIVER_HAVE_DMA) &&
        !drm_core_check_feature(dev, DRIVER_MODESET)) {
        dev->buf_use = 0;
        atomic_set(&dev->buf_alloc, 0);

        i = drm_dma_setup(dev);
        if (i < 0)
            return i;
    }

    for (i = 0; i < DRM_ARRAY_SIZE(dev->counts); i++)
        atomic_set(&dev->counts[i], 0);

    dev->context_flag = 0;
    dev->last_context = 0;
    dev->if_version = 0;


    DRM_DEBUG("\n");

    /*
     * The kernel's context could be created here, but is now created
     * in drm_dma_enqueue.  This is more resource-efficient for
     * hardware that does not do DMA, but may mean that
     * drm_select_queue fails between the time the interrupt is
     * initialized and the time the queues are initialized.
     */

    first_call = false;
    return 0;
}

/**
 * Open file.
 *
 * \return zero on success or a negative number on failure.
 *
 * Searches the DRM device with the same minor number, calls open_helper(), and
 * increments the device open count. If the open count was previous at zero,
 * i.e., it's the first that the device is open, then calls setup().
 */
int drm_open(struct drm_minor *minor, int clone_id, int flags, cred_t *credp)
{
    struct drm_device *dev = minor->dev;
    int retcode = 0;

    DRM_DEBUG("minor->index=%d, clone_id=%d", minor->index, clone_id);

    retcode = drm_open_helper(minor, clone_id, flags, credp);
    if (!retcode) {
        atomic_inc(&dev->counts[_DRM_STAT_OPENS]);
        spin_lock(&dev->count_lock);
        if (!dev->open_count++) {
            spin_unlock(&dev->count_lock);
            retcode = drm_setup(dev);
            goto out;
        }
        spin_unlock(&dev->count_lock);
    }
out:
    return retcode;
}

/**
 * Called whenever a process opens /dev/drm.
 *
 * 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 drm_minor *minor,
            int clone_id, int flags, cred_t *credp)
{
    struct drm_device *dev = minor->dev;
    struct drm_file *priv;
    int minor_id = minor->index;
    int ret;

    if (flags & FEXCL)
        return -EBUSY;  /* No exclusive opens */

    if (dev->switch_power_state != DRM_SWITCH_POWER_ON)
        return -EINVAL;

    DRM_DEBUG("pid = %d, minor = %d\n", ddi_get_pid(), minor_id);

    priv = kmalloc(sizeof(*priv), GFP_KERNEL);
    if (!priv)
        return -ENOMEM;

    (void) memset(priv, 0, sizeof(*priv));
    (void) idr_replace(&minor->clone_idr, priv, clone_id);  /* OSOL_drm */
    priv->uid = crgetsuid(credp);
    priv->pid = ddi_get_pid();
    priv->minor = minor;
    priv->ioctl_count = 0;
    /* for compatibility root is always authenticated */
    priv->authenticated = DRM_SUSER(credp);
    priv->lock_count = 0;

    INIT_LIST_HEAD(&priv->lhead);
    INIT_LIST_HEAD(&priv->fbs);
    mutex_init(&priv->fbs_lock, NULL, MUTEX_DRIVER, NULL);
    INIT_LIST_HEAD(&priv->event_list);
    DRM_INIT_WAITQUEUE(&priv->event_wait, DRM_INTR_PRI(dev));
    priv->event_space = 4096; /* set aside 4k for event buffer */

    if (dev->driver->driver_features & DRIVER_GEM)
        drm_gem_open(dev, priv);

    if (dev->driver->open) {
        ret = dev->driver->open(dev, priv);
        if (ret < 0)
            goto out_free;
    }


    /* if there is no current master make this fd it */
    mutex_lock(&dev->struct_mutex);
    if (!priv->minor->master) {
        /* create a new master */
        priv->minor->master = drm_master_create(priv->minor);
        if (!priv->minor->master) {
            mutex_unlock(&dev->struct_mutex);
            ret = -ENOMEM;
            goto out_free;
        }

        priv->is_master = 1;
        /* take another reference for the copy in the local file priv */
        priv->master = drm_master_get(priv->minor->master);

        priv->authenticated = 1;

        mutex_unlock(&dev->struct_mutex);
        if (dev->driver->master_create) {
            ret = dev->driver->master_create(dev, priv->master);
            if (ret) {
                mutex_lock(&dev->struct_mutex);
                /* drop both references if this fails */
                drm_master_put(&priv->minor->master);
                drm_master_put(&priv->master);
                mutex_unlock(&dev->struct_mutex);
                goto out_free;
            }
        }
        mutex_lock(&dev->struct_mutex);
        if (dev->driver->master_set) {
            ret = dev->driver->master_set(dev, priv, true);
            if (ret) {
                /* drop both references if this fails */
                drm_master_put(&priv->minor->master);
                drm_master_put(&priv->master);
                mutex_unlock(&dev->struct_mutex);
                goto out_free;
            }
        }
        mutex_unlock(&dev->struct_mutex);
    } else {
        /* get a reference to the master */
        priv->master = drm_master_get(priv->minor->master);
        mutex_unlock(&dev->struct_mutex);
    }

    mutex_lock(&dev->struct_mutex);
    list_add(&priv->lhead, &dev->filelist, (caddr_t)priv);
    mutex_unlock(&dev->struct_mutex);

    return 0;
out_free:
    kfree(priv, sizeof (*priv));
    return ret;
}

void drm_master_release(struct drm_device *dev, struct drm_file *fpriv)
{
    struct drm_master *master = fpriv->master;

    if (drm_i_have_hw_lock(dev, fpriv)) {
        DRM_DEBUG("Process %d dead, freeing lock for context %d",
            DRM_CURRENTPID,  _DRM_LOCKING_CONTEXT(master->lock.hw_lock->lock));
        (void) drm_lock_free(&master->lock,
            _DRM_LOCKING_CONTEXT(master->lock.hw_lock->lock));
    }

}

static void drm_events_release(struct drm_file *file_priv)
{
    struct drm_device *dev = file_priv->minor->dev;
    struct drm_pending_event *e, *et;
    struct drm_pending_vblank_event *v, *vt;
    unsigned long flags;

    spin_lock_irqsave(&dev->event_lock, flags);

    /* Remove pending flips */
    list_for_each_entry_safe(v, vt, struct drm_pending_vblank_event, &dev->vblank_event_list, base.link)
    if (v->base.file_priv == file_priv) {
        list_del(&v->base.link);
        drm_vblank_put(dev, v->pipe);
        v->base.destroy(&v->base, sizeof(struct drm_pending_vblank_event));
    }

    /* Remove unconsumed events */
    list_for_each_entry_safe(e, et, struct drm_pending_event, &file_priv->event_list, link)
        e->destroy(e,  sizeof(struct drm_pending_vblank_event));

    spin_unlock_irqrestore(&dev->event_lock, flags);
}

/**
 * Release file.
 *
 * \return zero on success or a negative number on failure.
 *
 * If the hardware lock is held then free it, and take it again for the kernel
 * context since it's necessary to reclaim buffers. Unlink the file private
 * data from its list and free it. Decreases the open count and if it reaches
 * zero calls drm_lastclose().
 */
int
drm_release(struct drm_file *file_priv)
{
    struct drm_device *dev = file_priv->minor->dev;
    int retcode = 0;


    DRM_DEBUG("open_count = %d\n", dev->open_count);

    if (dev->driver->preclose)
        dev->driver->preclose(dev, file_priv);

    /* ========================================================
     * Begin inline drm_release
     */

    /* Release any auth tokens that might point to this file_priv,
       (do that under the drm_global_mutex) */
    if (file_priv->magic)
        (void) drm_remove_magic(file_priv->master, file_priv->magic);

    /* if the master has gone away we can't do anything with the lock */
    if (file_priv->minor->master)
        drm_master_release(dev, file_priv);

    if (drm_core_check_feature(dev, DRIVER_HAVE_DMA))
        drm_core_reclaim_buffers(dev, file_priv);

    drm_events_release(file_priv);

    if (dev->driver->driver_features & DRIVER_MODESET)
        drm_fb_release(file_priv);

    if (dev->driver->driver_features & DRIVER_GEM)
        drm_gem_release(dev, file_priv);

    mutex_lock(&dev->ctxlist_mutex);
    if (!list_empty(&dev->ctxlist)) {
        struct drm_ctx_list *pos, *n;

        list_for_each_entry_safe(pos, n, struct drm_ctx_list, &dev->ctxlist, head) {
            if (pos->tag == file_priv &&
                pos->handle != DRM_KERNEL_CONTEXT) {
                if (dev->driver->context_dtor)
                    dev->driver->context_dtor(dev,
                                  pos->handle);

                drm_ctxbitmap_free(dev, pos->handle);

                list_del(&pos->head);
                kfree(pos, sizeof (*pos));
                --dev->ctx_count;
            }
        }
    }
    mutex_unlock(&dev->ctxlist_mutex);

    mutex_lock(&dev->struct_mutex);

    if (file_priv->is_master) {
        struct drm_master *master = file_priv->master;
        struct drm_file *temp;
        list_for_each_entry(temp, struct drm_file, &dev->filelist, lhead) {
            if ((temp->master == file_priv->master) &&
                (temp != file_priv))
                temp->authenticated = 0;
        }

        /**
         * Since the master is disappearing, so is the
         * possibility to lock.
         */

        if (master->lock.hw_lock) {
            master->lock.hw_lock = NULL;
            master->lock.file_priv = NULL;
        }

        if (file_priv->minor->master == file_priv->master) {
            /* drop the reference held my the minor */
            if (dev->driver->master_drop)
                dev->driver->master_drop(dev, file_priv, true);
            drm_master_put(&file_priv->minor->master);
        }
    }

    /* drop the reference held my the file priv */
    drm_master_put(&file_priv->master);
    file_priv->is_master = 0;
    list_del(&file_priv->lhead);
    mutex_unlock(&dev->struct_mutex);

    if (dev->driver->postclose)
        dev->driver->postclose(dev, file_priv);
    kfree(file_priv, sizeof (*file_priv));

    /* ========================================================
     * End inline drm_release
     */

    atomic_inc(&dev->counts[_DRM_STAT_CLOSES]);
    spin_lock(&dev->count_lock);
    if (!--dev->open_count) {
        if (atomic_read(&dev->ioctl_count)) {
            DRM_ERROR("Device busy: %d\n",
                  atomic_read(&dev->ioctl_count));
            spin_unlock(&dev->count_lock);
            return -EBUSY;
        }
        spin_unlock(&dev->count_lock);
        return drm_lastclose(dev);
    }
    spin_unlock(&dev->count_lock);

    return retcode;
}

static bool
drm_dequeue_event(struct drm_file *file_priv,
    size_t total, size_t max, struct drm_pending_event **out)
{
    struct drm_device *dev = file_priv->minor->dev;
    struct drm_pending_event *e;
    unsigned long flags;
    bool ret = false;

    spin_lock_irqsave(&dev->event_lock, flags);

    *out = NULL;
    if (list_empty(&file_priv->event_list))
        goto out;
    e = list_first_entry(&file_priv->event_list,
    struct drm_pending_event, link);
    if (e->event->length + total > max)
        goto out;

    file_priv->event_space += e->event->length;
    list_del(&e->link);
    *out = e;
    ret = true;

out:
    spin_unlock_irqrestore(&dev->event_lock, flags);
    return ret;
}

ssize_t drm_read(struct drm_file *file_priv, struct uio *uiop)
{
    struct drm_pending_event *e;
    size_t total;
    int ret = 0;

    DRM_WAIT(ret, &file_priv->event_wait,
        !list_empty(&file_priv->event_list));
    if (ret < 0) {
        DRM_ERROR("returns %d event_list is %d", ret, list_empty(&file_priv->event_list));
        return ret;
    }

    total = 0;
    while (drm_dequeue_event(file_priv, total, uiop->uio_iov->iov_len, &e)) {
        ret = uiomove((caddr_t)e->event, e->event->length, UIO_READ, uiop);
        if (ret) {
            DRM_ERROR("Failed to copy to user: %d", ret);
            return (0);
        }
        total += e->event->length;
        e->destroy(e, sizeof(struct drm_pending_vblank_event));
    }

    return total;
}

short drm_poll(struct drm_file *file_priv, short events)
{
    short revent = 0;

    if (!list_empty(&file_priv->event_list)) {
        if (events & POLLIN)
            revent |= POLLIN;
        if (events & POLLRDNORM)
            revent |= POLLRDNORM;
    }

    return revent;
}