[PATCH 1/2] drm/drm_vma_manager: Add drm_vma_node_allow_once()
Tvrtko Ursulin
tvrtko.ursulin at linux.intel.com
Wed Jan 18 13:34:07 UTC 2023
On 18/01/2023 13:19, Tvrtko Ursulin wrote:
>
> Hi Dave & Daniel,
>
> On 17/01/2023 17:52, Nirmoy Das wrote:
>> Currently there is no easy way for a drm driver to safely check and allow
>> drm_vma_offset_node for a drm file just once. Allow drm drivers to call
>> non-refcounted version of drm_vma_node_allow() so that a driver doesn't
>> need to keep track of each drm_vma_node_allow() to call subsequent
>> drm_vma_node_revoke() to prevent memory leak.
>>
>> Cc: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>
>> Cc: Maxime Ripard <mripard at kernel.org>
>> Cc: Thomas Zimmermann <tzimmermann at suse.de>
>> Cc: David Airlie <airlied at gmail.com>
>> Cc: Daniel Vetter <daniel at ffwll.ch>
>> Cc: Tvrtko Ursulin <tvrtko.ursulin at linux.intel.com>
>> Cc: Andi Shyti <andi.shyti at linux.intel.com>
>
> Okay to take this via drm-intel?
Or both patches via drm-misc-fixes so that we avoid drm-intel fixes flow?
Regards,
Tvrtko
> Do we need an additional r-b from the DRM core side?
>
> Regards,
>
> Tvrtko
>
>> Suggested-by: Chris Wilson <chris.p.wilson at intel.com>
>> Signed-off-by: Nirmoy Das <nirmoy.das at intel.com>
>> ---
>> drivers/gpu/drm/drm_vma_manager.c | 76 ++++++++++++++++++++++---------
>> include/drm/drm_vma_manager.h | 1 +
>> 2 files changed, 55 insertions(+), 22 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/drm_vma_manager.c
>> b/drivers/gpu/drm/drm_vma_manager.c
>> index 7de37f8c68fd..83229a031af0 100644
>> --- a/drivers/gpu/drm/drm_vma_manager.c
>> +++ b/drivers/gpu/drm/drm_vma_manager.c
>> @@ -240,27 +240,8 @@ void drm_vma_offset_remove(struct
>> drm_vma_offset_manager *mgr,
>> }
>> EXPORT_SYMBOL(drm_vma_offset_remove);
>> -/**
>> - * drm_vma_node_allow - Add open-file to list of allowed users
>> - * @node: Node to modify
>> - * @tag: Tag of file to remove
>> - *
>> - * Add @tag to the list of allowed open-files for this node. If @tag is
>> - * already on this list, the ref-count is incremented.
>> - *
>> - * The list of allowed-users is preserved across drm_vma_offset_add()
>> and
>> - * drm_vma_offset_remove() calls. You may even call it if the node is
>> currently
>> - * not added to any offset-manager.
>> - *
>> - * You must remove all open-files the same number of times as you
>> added them
>> - * before destroying the node. Otherwise, you will leak memory.
>> - *
>> - * This is locked against concurrent access internally.
>> - *
>> - * RETURNS:
>> - * 0 on success, negative error code on internal failure (out-of-mem)
>> - */
>> -int drm_vma_node_allow(struct drm_vma_offset_node *node, struct
>> drm_file *tag)
>> +static int vma_node_allow(struct drm_vma_offset_node *node,
>> + struct drm_file *tag, bool ref_counted)
>> {
>> struct rb_node **iter;
>> struct rb_node *parent = NULL;
>> @@ -282,7 +263,8 @@ int drm_vma_node_allow(struct drm_vma_offset_node
>> *node, struct drm_file *tag)
>> entry = rb_entry(*iter, struct drm_vma_offset_file, vm_rb);
>> if (tag == entry->vm_tag) {
>> - entry->vm_count++;
>> + if (ref_counted)
>> + entry->vm_count++;
>> goto unlock;
>> } else if (tag > entry->vm_tag) {
>> iter = &(*iter)->rb_right;
>> @@ -307,8 +289,58 @@ int drm_vma_node_allow(struct drm_vma_offset_node
>> *node, struct drm_file *tag)
>> kfree(new);
>> return ret;
>> }
>> +
>> +/**
>> + * drm_vma_node_allow - Add open-file to list of allowed users
>> + * @node: Node to modify
>> + * @tag: Tag of file to remove
>> + *
>> + * Add @tag to the list of allowed open-files for this node. If @tag is
>> + * already on this list, the ref-count is incremented.
>> + *
>> + * The list of allowed-users is preserved across drm_vma_offset_add()
>> and
>> + * drm_vma_offset_remove() calls. You may even call it if the node is
>> currently
>> + * not added to any offset-manager.
>> + *
>> + * You must remove all open-files the same number of times as you
>> added them
>> + * before destroying the node. Otherwise, you will leak memory.
>> + *
>> + * This is locked against concurrent access internally.
>> + *
>> + * RETURNS:
>> + * 0 on success, negative error code on internal failure (out-of-mem)
>> + */
>> +int drm_vma_node_allow(struct drm_vma_offset_node *node, struct
>> drm_file *tag)
>> +{
>> + return vma_node_allow(node, tag, true);
>> +}
>> EXPORT_SYMBOL(drm_vma_node_allow);
>> +/**
>> + * drm_vma_node_allow_once - Add open-file to list of allowed users
>> + * @node: Node to modify
>> + * @tag: Tag of file to remove
>> + *
>> + * Add @tag to the list of allowed open-files for this node.
>> + *
>> + * The list of allowed-users is preserved across drm_vma_offset_add()
>> and
>> + * drm_vma_offset_remove() calls. You may even call it if the node is
>> currently
>> + * not added to any offset-manager.
>> + *
>> + * This is not ref-counted unlike drm_vma_node_allow() hence
>> drm_vma_node_revoke()
>> + * should only be called once after this.
>> + *
>> + * This is locked against concurrent access internally.
>> + *
>> + * RETURNS:
>> + * 0 on success, negative error code on internal failure (out-of-mem)
>> + */
>> +int drm_vma_node_allow_once(struct drm_vma_offset_node *node, struct
>> drm_file *tag)
>> +{
>> + return vma_node_allow(node, tag, false);
>> +}
>> +EXPORT_SYMBOL(drm_vma_node_allow_once);
>> +
>> /**
>> * drm_vma_node_revoke - Remove open-file from list of allowed users
>> * @node: Node to modify
>> diff --git a/include/drm/drm_vma_manager.h
>> b/include/drm/drm_vma_manager.h
>> index 4f8c35206f7c..6c2a2f21dbf0 100644
>> --- a/include/drm/drm_vma_manager.h
>> +++ b/include/drm/drm_vma_manager.h
>> @@ -74,6 +74,7 @@ void drm_vma_offset_remove(struct
>> drm_vma_offset_manager *mgr,
>> struct drm_vma_offset_node *node);
>> int drm_vma_node_allow(struct drm_vma_offset_node *node, struct
>> drm_file *tag);
>> +int drm_vma_node_allow_once(struct drm_vma_offset_node *node, struct
>> drm_file *tag);
>> void drm_vma_node_revoke(struct drm_vma_offset_node *node,
>> struct drm_file *tag);
>> bool drm_vma_node_is_allowed(struct drm_vma_offset_node *node,
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