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, 109 insertions, 0 deletions

diff --git a/Documentation/driver-api/infiniband.rst b/Documentation/driver-api/infiniband.rst
new file mode 100644
index 000000000..d48f24677
--- /dev/null
+++ b/Documentation/driver-api/infiniband.rst
@@ -0,0 +1,109 @@
+===========================================
+InfiniBand and Remote DMA (RDMA) Interfaces
+===========================================
+
+Introduction and Overview
+=========================
+
+TBD
+
+InfiniBand core interfaces
+==========================
+
+.. kernel-doc:: drivers/infiniband/core/iwpm_util.h
+    :internal:
+
+.. kernel-doc:: drivers/infiniband/core/cq.c
+    :export:
+
+.. kernel-doc:: drivers/infiniband/core/cm.c
+    :export:
+
+.. kernel-doc:: drivers/infiniband/core/rw.c
+    :export:
+
+.. kernel-doc:: drivers/infiniband/core/device.c
+    :export:
+
+.. kernel-doc:: drivers/infiniband/core/verbs.c
+    :export:
+
+.. kernel-doc:: drivers/infiniband/core/packer.c
+    :export:
+
+.. kernel-doc:: drivers/infiniband/core/sa_query.c
+    :export:
+
+.. kernel-doc:: drivers/infiniband/core/ud_header.c
+    :export:
+
+.. kernel-doc:: drivers/infiniband/core/umem.c
+    :export:
+
+.. kernel-doc:: drivers/infiniband/core/umem_odp.c
+    :export:
+
+RDMA Verbs transport library
+============================
+
+.. kernel-doc:: drivers/infiniband/sw/rdmavt/mr.c
+    :export:
+
+.. kernel-doc:: drivers/infiniband/sw/rdmavt/rc.c
+    :export:
+
+.. kernel-doc:: drivers/infiniband/sw/rdmavt/ah.c
+    :export:
+
+.. kernel-doc:: drivers/infiniband/sw/rdmavt/vt.c
+    :export:
+
+.. kernel-doc:: drivers/infiniband/sw/rdmavt/cq.c
+    :export:
+
+.. kernel-doc:: drivers/infiniband/sw/rdmavt/qp.c
+    :export:
+
+.. kernel-doc:: drivers/infiniband/sw/rdmavt/mcast.c
+    :export:
+
+Upper Layer Protocols
+=====================
+
+iSCSI Extensions for RDMA (iSER)
+--------------------------------
+
+.. kernel-doc:: drivers/infiniband/ulp/iser/iscsi_iser.h
+   :internal:
+
+.. kernel-doc:: drivers/infiniband/ulp/iser/iscsi_iser.c
+   :functions: iscsi_iser_pdu_alloc iser_initialize_task_headers
+               iscsi_iser_task_init iscsi_iser_mtask_xmit iscsi_iser_task_xmit
+               iscsi_iser_cleanup_task iscsi_iser_check_protection
+               iscsi_iser_conn_create iscsi_iser_conn_bind
+               iscsi_iser_conn_start iscsi_iser_conn_stop
+               iscsi_iser_session_destroy iscsi_iser_session_create
+               iscsi_iser_set_param iscsi_iser_ep_connect iscsi_iser_ep_poll
+               iscsi_iser_ep_disconnect
+
+.. kernel-doc:: drivers/infiniband/ulp/iser/iser_initiator.c
+   :internal:
+
+.. kernel-doc:: drivers/infiniband/ulp/iser/iser_verbs.c
+   :internal:
+
+InfiniBand SCSI RDMA protocol target support
+--------------------------------------------
+
+.. kernel-doc:: drivers/infiniband/ulp/srpt/ib_srpt.h
+   :internal:
+
+.. kernel-doc:: drivers/infiniband/ulp/srpt/ib_srpt.c
+   :internal:
+
+iSCSI Extensions for RDMA (iSER) target support
+-----------------------------------------------
+
+.. kernel-doc:: drivers/infiniband/ulp/isert/ib_isert.c
+   :internal:
+