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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
commit4352b8aee98005853aa63f57d6377282de17a33f (patch)
tree27614d7a9ef05c32d089004e104364ce42324837 /drivers/media/mc/mc-request.c
downloadlinux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz
linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip
Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted
Pull I3C updates from Alexandre Belloni: "A new driver this cycle, for the AMD AXI I3C controller. There are also new features such as IBI wakeup support, SETAASA device discovery and ACPI support for the the DAA methods, meaning we can now communicate with the SPD devices on DDR5 modules. New driver: - AMD AXI I3C master controller Subsystem: - I3C Common Command Code (CCC) handling improvements, especially around GET CCCs - SETAASA device discovery support - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as well as I2C devices on I3C bus - IBI-based wakeup support Drivers: - dw: SETAASA support - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C controller support, PIO queue management support for HCI v1.2 - renesas: improve suspend to RAM support, add runtime PM support" * tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits) i3c: dw: reduce do_daa time if there's no client i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2 i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode i3c: dw: rename "pclk" to "apb" to match dt-binding i3c: dw: make struct dw_i3c_cmd smaller i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding i3c: renesas: Don't register devices when ENTDAA times out i3c: master: dw-i3c-master: fix OD timing for first broadcast i3c: mipi-i3c-hci: Advertise IBI wakeup capability i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev() i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI i3c: master: Reject IBI requests from non-IBI-capable devices i3c: master: Add helper to query bus wakeup requirements i3c: master: Report wakeup events for IBIs i3c: master: Support IBI-based wakeup capability i3c: master: Fix potential UAF in i3c_device_match() i3c: master: Fix potential UAF in i3c_device_uevent() i3c: Make dev->desc locking assumptions explicit i3c: master: Fix use-after-free of master->this ...
Diffstat (limited to 'drivers/media/mc/mc-request.c')
-rw-r--r--drivers/media/mc/mc-request.c539
1 files changed, 539 insertions, 0 deletions
diff --git a/drivers/media/mc/mc-request.c b/drivers/media/mc/mc-request.c
new file mode 100644
index 000000000..13e776488
--- /dev/null
+++ b/drivers/media/mc/mc-request.c
@@ -0,0 +1,539 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Media device request objects
+ *
+ * Copyright 2018 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
+ * Copyright (C) 2018 Intel Corporation
+ * Copyright (C) 2018 Google, Inc.
+ *
+ * Author: Hans Verkuil <hverkuil@kernel.org>
+ * Author: Sakari Ailus <sakari.ailus@linux.intel.com>
+ */
+
+#include <linux/anon_inodes.h>
+#include <linux/file.h>
+#include <linux/refcount.h>
+
+#include <media/media-device.h>
+#include <media/media-request.h>
+
+static const char * const request_state[] = {
+ [MEDIA_REQUEST_STATE_IDLE] = "idle",
+ [MEDIA_REQUEST_STATE_VALIDATING] = "validating",
+ [MEDIA_REQUEST_STATE_QUEUED] = "queued",
+ [MEDIA_REQUEST_STATE_COMPLETE] = "complete",
+ [MEDIA_REQUEST_STATE_CLEANING] = "cleaning",
+ [MEDIA_REQUEST_STATE_UPDATING] = "updating",
+};
+
+static const char *
+media_request_state_str(enum media_request_state state)
+{
+ BUILD_BUG_ON(ARRAY_SIZE(request_state) != NR_OF_MEDIA_REQUEST_STATE);
+
+ if (WARN_ON(state >= ARRAY_SIZE(request_state)))
+ return "invalid";
+ return request_state[state];
+}
+
+static void media_request_clean(struct media_request *req)
+{
+ struct media_request_object *obj, *obj_safe;
+
+ /* Just a sanity check. No other code path is allowed to change this. */
+ WARN_ON(req->state != MEDIA_REQUEST_STATE_CLEANING);
+ WARN_ON(req->updating_count);
+ WARN_ON(req->access_count);
+
+ list_for_each_entry_safe(obj, obj_safe, &req->objects, list) {
+ media_request_object_unbind(obj);
+ media_request_object_put(obj);
+ }
+
+ req->updating_count = 0;
+ req->access_count = 0;
+ WARN_ON(req->num_incomplete_objects);
+ req->num_incomplete_objects = 0;
+ req->manual_completion = false;
+ wake_up_interruptible_all(&req->poll_wait);
+}
+
+static void media_request_release(struct kref *kref)
+{
+ struct media_request *req =
+ container_of(kref, struct media_request, kref);
+ struct media_device *mdev = req->mdev;
+
+ dev_dbg(mdev->dev, "request: release %s\n", req->debug_str);
+
+ /* No other users, no need for a spinlock */
+ req->state = MEDIA_REQUEST_STATE_CLEANING;
+
+ media_request_clean(req);
+
+ if (mdev->ops->req_free)
+ mdev->ops->req_free(req);
+ else
+ kfree(req);
+ atomic_dec(&mdev->num_requests);
+}
+
+void media_request_put(struct media_request *req)
+{
+ kref_put(&req->kref, media_request_release);
+}
+EXPORT_SYMBOL_GPL(media_request_put);
+
+static int media_request_close(struct inode *inode, struct file *filp)
+{
+ struct media_request *req = filp->private_data;
+
+ media_request_put(req);
+ return 0;
+}
+
+static __poll_t media_request_poll(struct file *filp,
+ struct poll_table_struct *wait)
+{
+ struct media_request *req = filp->private_data;
+ unsigned long flags;
+ __poll_t ret = 0;
+
+ if (!(poll_requested_events(wait) & EPOLLPRI))
+ return 0;
+
+ poll_wait(filp, &req->poll_wait, wait);
+ spin_lock_irqsave(&req->lock, flags);
+ if (req->state == MEDIA_REQUEST_STATE_COMPLETE) {
+ ret = EPOLLPRI;
+ goto unlock;
+ }
+ if (req->state != MEDIA_REQUEST_STATE_QUEUED) {
+ ret = EPOLLERR;
+ goto unlock;
+ }
+
+unlock:
+ spin_unlock_irqrestore(&req->lock, flags);
+ return ret;
+}
+
+static long media_request_ioctl_queue(struct media_request *req)
+{
+ struct media_device *mdev = req->mdev;
+ enum media_request_state state;
+ unsigned long flags;
+ int ret;
+
+ dev_dbg(mdev->dev, "request: queue %s\n", req->debug_str);
+
+ /*
+ * Ensure the request that is validated will be the one that gets queued
+ * next by serialising the queueing process. This mutex is also used
+ * to serialize with canceling a vb2 queue and with setting values such
+ * as controls in a request.
+ */
+ mutex_lock(&mdev->req_queue_mutex);
+
+ media_request_get(req);
+
+ spin_lock_irqsave(&req->lock, flags);
+ if (req->state == MEDIA_REQUEST_STATE_IDLE)
+ req->state = MEDIA_REQUEST_STATE_VALIDATING;
+ state = req->state;
+ spin_unlock_irqrestore(&req->lock, flags);
+ if (state != MEDIA_REQUEST_STATE_VALIDATING) {
+ dev_dbg(mdev->dev,
+ "request: unable to queue %s, request in state %s\n",
+ req->debug_str, media_request_state_str(state));
+ media_request_put(req);
+ mutex_unlock(&mdev->req_queue_mutex);
+ return -EBUSY;
+ }
+
+ ret = mdev->ops->req_validate(req);
+
+ /*
+ * If the req_validate was successful, then we mark the state as QUEUED
+ * and call req_queue. The reason we set the state first is that this
+ * allows req_queue to unbind or complete the queued objects in case
+ * they are immediately 'consumed'. State changes from QUEUED to another
+ * state can only happen if either the driver changes the state or if
+ * the user cancels the vb2 queue. The driver can only change the state
+ * after each object is queued through the req_queue op (and note that
+ * that op cannot fail), so setting the state to QUEUED up front is
+ * safe.
+ *
+ * The other reason for changing the state is if the vb2 queue is
+ * canceled, and that uses the req_queue_mutex which is still locked
+ * while req_queue is called, so that's safe as well.
+ */
+ spin_lock_irqsave(&req->lock, flags);
+ req->state = ret ? MEDIA_REQUEST_STATE_IDLE
+ : MEDIA_REQUEST_STATE_QUEUED;
+ spin_unlock_irqrestore(&req->lock, flags);
+
+ if (!ret)
+ mdev->ops->req_queue(req);
+
+ mutex_unlock(&mdev->req_queue_mutex);
+
+ if (ret) {
+ dev_dbg(mdev->dev, "request: can't queue %s (%d)\n",
+ req->debug_str, ret);
+ media_request_put(req);
+ }
+
+ return ret;
+}
+
+static long media_request_ioctl_reinit(struct media_request *req)
+{
+ struct media_device *mdev = req->mdev;
+ unsigned long flags;
+
+ mutex_lock(&mdev->req_queue_mutex);
+
+ spin_lock_irqsave(&req->lock, flags);
+ if (req->state != MEDIA_REQUEST_STATE_IDLE &&
+ req->state != MEDIA_REQUEST_STATE_COMPLETE) {
+ dev_dbg(mdev->dev,
+ "request: %s not in idle or complete state, cannot reinit\n",
+ req->debug_str);
+ spin_unlock_irqrestore(&req->lock, flags);
+ mutex_unlock(&mdev->req_queue_mutex);
+ return -EBUSY;
+ }
+ if (req->access_count) {
+ dev_dbg(mdev->dev,
+ "request: %s is being accessed, cannot reinit\n",
+ req->debug_str);
+ spin_unlock_irqrestore(&req->lock, flags);
+ mutex_unlock(&mdev->req_queue_mutex);
+ return -EBUSY;
+ }
+ req->state = MEDIA_REQUEST_STATE_CLEANING;
+ spin_unlock_irqrestore(&req->lock, flags);
+
+ media_request_clean(req);
+
+ spin_lock_irqsave(&req->lock, flags);
+ req->state = MEDIA_REQUEST_STATE_IDLE;
+ spin_unlock_irqrestore(&req->lock, flags);
+ mutex_unlock(&mdev->req_queue_mutex);
+
+ return 0;
+}
+
+static long media_request_ioctl(struct file *filp, unsigned int cmd,
+ unsigned long arg)
+{
+ struct media_request *req = filp->private_data;
+
+ switch (cmd) {
+ case MEDIA_REQUEST_IOC_QUEUE:
+ return media_request_ioctl_queue(req);
+ case MEDIA_REQUEST_IOC_REINIT:
+ return media_request_ioctl_reinit(req);
+ default:
+ return -ENOIOCTLCMD;
+ }
+}
+
+static const struct file_operations request_fops = {
+ .owner = THIS_MODULE,
+ .poll = media_request_poll,
+ .unlocked_ioctl = media_request_ioctl,
+#ifdef CONFIG_COMPAT
+ .compat_ioctl = media_request_ioctl,
+#endif /* CONFIG_COMPAT */
+ .release = media_request_close,
+};
+
+struct media_request *
+media_request_get_by_fd(struct media_device *mdev, int request_fd)
+{
+ struct media_request *req;
+
+ if (!mdev || !mdev->ops ||
+ !mdev->ops->req_validate || !mdev->ops->req_queue)
+ return ERR_PTR(-EBADR);
+
+ CLASS(fd, f)(request_fd);
+ if (fd_empty(f))
+ goto err;
+
+ if (fd_file(f)->f_op != &request_fops)
+ goto err;
+ req = fd_file(f)->private_data;
+ if (req->mdev != mdev)
+ goto err;
+
+ /*
+ * Note: as long as someone has an open filehandle of the request,
+ * the request can never be released. The fdget() above ensures that
+ * even if userspace closes the request filehandle, the release()
+ * fop won't be called, so the media_request_get() always succeeds
+ * and there is no race condition where the request was released
+ * before media_request_get() is called.
+ */
+ media_request_get(req);
+ return req;
+
+err:
+ dev_dbg(mdev->dev, "cannot find request_fd %d\n", request_fd);
+ return ERR_PTR(-EINVAL);
+}
+EXPORT_SYMBOL_GPL(media_request_get_by_fd);
+
+int media_request_alloc(struct media_device *mdev, int *alloc_fd)
+{
+ struct media_request *req;
+ int ret;
+
+ /* Either both are NULL or both are non-NULL */
+ if (WARN_ON(!mdev->ops->req_alloc ^ !mdev->ops->req_free))
+ return -ENOMEM;
+
+ if (mdev->ops->req_alloc)
+ req = mdev->ops->req_alloc(mdev);
+ else
+ req = kzalloc_obj(*req);
+ if (!req)
+ return -ENOMEM;
+
+ req->mdev = mdev;
+ req->state = MEDIA_REQUEST_STATE_IDLE;
+ req->num_incomplete_objects = 0;
+ req->manual_completion = false;
+ kref_init(&req->kref);
+ INIT_LIST_HEAD(&req->objects);
+ spin_lock_init(&req->lock);
+ init_waitqueue_head(&req->poll_wait);
+ req->updating_count = 0;
+ req->access_count = 0;
+
+ FD_PREPARE(fdf, O_CLOEXEC,
+ anon_inode_getfile("request", &request_fops, NULL,
+ O_CLOEXEC));
+ if (fdf.err) {
+ ret = fdf.err;
+ goto err_free_req;
+ }
+
+ fd_prepare_file(fdf)->private_data = req;
+
+ snprintf(req->debug_str, sizeof(req->debug_str), "%u:%d",
+ atomic_inc_return(&mdev->request_id), fd_prepare_fd(fdf));
+ atomic_inc(&mdev->num_requests);
+ dev_dbg(mdev->dev, "request: allocated %s\n", req->debug_str);
+
+ *alloc_fd = fd_publish(fdf);
+
+ return 0;
+
+err_free_req:
+ if (mdev->ops->req_free)
+ mdev->ops->req_free(req);
+ else
+ kfree(req);
+
+ return ret;
+}
+
+static void media_request_object_release(struct kref *kref)
+{
+ struct media_request_object *obj =
+ container_of(kref, struct media_request_object, kref);
+ struct media_request *req = obj->req;
+ struct media_device *mdev = obj->mdev;
+
+ if (WARN_ON(req))
+ media_request_object_unbind(obj);
+ obj->ops->release(obj);
+ atomic_dec(&mdev->num_request_objects);
+}
+
+struct media_request_object *
+media_request_object_find(struct media_request *req,
+ const struct media_request_object_ops *ops,
+ void *priv)
+{
+ struct media_request_object *obj;
+ struct media_request_object *found = NULL;
+ unsigned long flags;
+
+ if (WARN_ON(!ops || !priv))
+ return NULL;
+
+ spin_lock_irqsave(&req->lock, flags);
+ list_for_each_entry(obj, &req->objects, list) {
+ if (obj->ops == ops && obj->priv == priv) {
+ media_request_object_get(obj);
+ found = obj;
+ break;
+ }
+ }
+ spin_unlock_irqrestore(&req->lock, flags);
+ return found;
+}
+EXPORT_SYMBOL_GPL(media_request_object_find);
+
+void media_request_object_put(struct media_request_object *obj)
+{
+ kref_put(&obj->kref, media_request_object_release);
+}
+EXPORT_SYMBOL_GPL(media_request_object_put);
+
+void media_request_object_init(struct media_request_object *obj)
+{
+ obj->ops = NULL;
+ obj->req = NULL;
+ obj->priv = NULL;
+ obj->completed = false;
+ INIT_LIST_HEAD(&obj->list);
+ kref_init(&obj->kref);
+}
+EXPORT_SYMBOL_GPL(media_request_object_init);
+
+int media_request_object_bind(struct media_request *req,
+ const struct media_request_object_ops *ops,
+ void *priv, bool is_buffer,
+ struct media_request_object *obj)
+{
+ unsigned long flags;
+ int ret = -EBUSY;
+
+ if (WARN_ON(!ops->release))
+ return -EBADR;
+
+ spin_lock_irqsave(&req->lock, flags);
+
+ if (WARN_ON(req->state != MEDIA_REQUEST_STATE_UPDATING &&
+ req->state != MEDIA_REQUEST_STATE_QUEUED))
+ goto unlock;
+
+ obj->req = req;
+ obj->ops = ops;
+ obj->priv = priv;
+ obj->mdev = req->mdev;
+
+ if (is_buffer)
+ list_add_tail(&obj->list, &req->objects);
+ else
+ list_add(&obj->list, &req->objects);
+ req->num_incomplete_objects++;
+ ret = 0;
+ atomic_inc(&obj->mdev->num_request_objects);
+
+unlock:
+ spin_unlock_irqrestore(&req->lock, flags);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(media_request_object_bind);
+
+void media_request_object_unbind(struct media_request_object *obj)
+{
+ struct media_request *req = obj->req;
+ unsigned long flags;
+ bool completed = false;
+
+ if (WARN_ON(!req))
+ return;
+
+ spin_lock_irqsave(&req->lock, flags);
+ list_del(&obj->list);
+ obj->req = NULL;
+
+ if (req->state == MEDIA_REQUEST_STATE_COMPLETE)
+ goto unlock;
+
+ if (WARN_ON(req->state == MEDIA_REQUEST_STATE_VALIDATING))
+ goto unlock;
+
+ if (req->state == MEDIA_REQUEST_STATE_CLEANING) {
+ if (!obj->completed)
+ req->num_incomplete_objects--;
+ goto unlock;
+ }
+
+ if (WARN_ON(!req->num_incomplete_objects))
+ goto unlock;
+
+ req->num_incomplete_objects--;
+ if (req->state == MEDIA_REQUEST_STATE_QUEUED &&
+ !req->num_incomplete_objects && !req->manual_completion) {
+ req->state = MEDIA_REQUEST_STATE_COMPLETE;
+ completed = true;
+ wake_up_interruptible_all(&req->poll_wait);
+ }
+
+unlock:
+ spin_unlock_irqrestore(&req->lock, flags);
+ if (obj->ops->unbind)
+ obj->ops->unbind(obj);
+ if (completed)
+ media_request_put(req);
+}
+EXPORT_SYMBOL_GPL(media_request_object_unbind);
+
+void media_request_object_complete(struct media_request_object *obj)
+{
+ struct media_request *req = obj->req;
+ unsigned long flags;
+ bool completed = false;
+
+ spin_lock_irqsave(&req->lock, flags);
+ if (obj->completed)
+ goto unlock;
+ obj->completed = true;
+ if (WARN_ON(!req->num_incomplete_objects) ||
+ WARN_ON(req->state != MEDIA_REQUEST_STATE_QUEUED))
+ goto unlock;
+
+ if (!--req->num_incomplete_objects && !req->manual_completion) {
+ req->state = MEDIA_REQUEST_STATE_COMPLETE;
+ wake_up_interruptible_all(&req->poll_wait);
+ completed = true;
+ }
+unlock:
+ spin_unlock_irqrestore(&req->lock, flags);
+ if (completed)
+ media_request_put(req);
+}
+EXPORT_SYMBOL_GPL(media_request_object_complete);
+
+void media_request_manual_complete(struct media_request *req)
+{
+ bool completed = false;
+ unsigned long flags;
+
+ if (WARN_ON_ONCE(!req))
+ return;
+
+ spin_lock_irqsave(&req->lock, flags);
+
+ if (WARN_ON_ONCE(!req->manual_completion))
+ goto unlock;
+
+ if (WARN_ON_ONCE(req->state != MEDIA_REQUEST_STATE_QUEUED))
+ goto unlock;
+
+ req->manual_completion = false;
+ /*
+ * It is expected that all other objects in this request are
+ * completed when this function is called. WARN if that is
+ * not the case.
+ */
+ if (!WARN_ON(req->num_incomplete_objects)) {
+ req->state = MEDIA_REQUEST_STATE_COMPLETE;
+ wake_up_interruptible_all(&req->poll_wait);
+ completed = true;
+ }
+
+unlock:
+ spin_unlock_irqrestore(&req->lock, flags);
+ if (completed)
+ media_request_put(req);
+}
+EXPORT_SYMBOL_GPL(media_request_manual_complete);