KVM: Don't pre-reserve xarray entries when storing empty/NULL attributesgrafted

Skip the xarray reservation loop when clearing all memory attributes, as
storing NULL only erases the entry and never needs to allocate, so no
reservation (and no cleanup of a failed one) is required in that case.

Suggested-by: Sean Christopherson <seanjc@google.com>
Cc: David Ballesteros <davimaba.v@proton.me>
Signed-off-by: Zeng Chi <zengchi@kylinos.cn>
Link: https://patch.msgid.link/20260921102442.1232375-1-zeng_chi911@163.com
[sean: split to separate patch]
Signed-off-by: Sean Christopherson <seanjc@google.com>

1 files changed, 36 insertions, 0 deletions

diff --git a/Documentation/gpu/nova/index.rst b/Documentation/gpu/nova/index.rst
new file mode 100644
index 000000000..2afa58e8f
--- /dev/null
+++ b/Documentation/gpu/nova/index.rst
@@ -0,0 +1,36 @@
+.. SPDX-License-Identifier: (GPL-2.0+ OR MIT)
+
+=======================
+nova NVIDIA GPU drivers
+=======================
+
+The nova driver project consists out of two separate drivers nova-core and
+nova-drm and intends to supersede the nouveau driver for NVIDIA GPUs based on
+the GPU System Processor (GSP).
+
+The following documents apply to both nova-core and nova-drm.
+
+.. toctree::
+   :titlesonly:
+
+   guidelines
+
+nova-core
+=========
+
+The nova-core driver is the core driver for NVIDIA GPUs based on GSP. nova-core,
+as the 1st level driver, provides an abstraction around the GPUs hard- and
+firmware interfaces providing a common base for 2nd level drivers, such as the
+vGPU manager VFIO driver and the nova-drm driver.
+
+.. toctree::
+   :titlesonly:
+
+   core/guidelines
+   core/todo
+   core/vbios
+   core/devinit
+   core/fsp
+   core/fwsec
+   core/falcon
+   core/tlv