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, 123 insertions, 0 deletions

diff --git a/include/uapi/rdma/mana-abi.h b/include/uapi/rdma/mana-abi.h
new file mode 100644
index 000000000..32cbbfc80
--- /dev/null
+++ b/include/uapi/rdma/mana-abi.h
@@ -0,0 +1,123 @@
+/* SPDX-License-Identifier: (GPL-2.0 WITH Linux-syscall-note) */
+/*
+ * Copyright (c) 2022, Microsoft Corporation. All rights reserved.
+ */
+
+#ifndef MANA_ABI_USER_H
+#define MANA_ABI_USER_H
+
+#include <linux/types.h>
+#include <rdma/ib_user_ioctl_verbs.h>
+
+/*
+ * Increment this value if any changes that break userspace ABI
+ * compatibility are made.
+ */
+
+#define MANA_IB_UVERBS_ABI_VERSION 1
+
+enum mana_ib_create_cq_flags {
+	/* Reserved for backward compatibility. Legacy
+	 * kernel versions use it to create CQs in RNIC
+	 */
+	MANA_IB_CREATE_RNIC_CQ	= 1 << 0,
+};
+
+struct mana_ib_create_cq {
+	__aligned_u64 buf_addr;
+	__u16	comp_mask;
+	__u16	reserved0;
+	__u32	reserved1;
+};
+
+struct mana_ib_create_cq_resp {
+	__u32 cqid;
+	__u32 reserved;
+};
+
+struct mana_ib_create_qp {
+	__aligned_u64 sq_buf_addr;
+	__u32 sq_buf_size;
+	__u32 port;
+};
+
+struct mana_ib_create_qp_resp {
+	__u32 sqid;
+	__u32 cqid;
+	__u32 tx_vp_offset;
+	__u32 reserved;
+};
+
+struct mana_ib_create_rc_qp {
+	__aligned_u64 queue_buf[4];
+	__u32 queue_size[4];
+};
+
+struct mana_ib_create_rc_qp_resp {
+	__u32 queue_id[4];
+};
+
+struct mana_ib_create_uc_qp {
+	__aligned_u64 queue_buf[3];
+	__u32 queue_size[3];
+	__u32 comp_mask;
+};
+
+struct mana_ib_create_uc_qp_resp {
+	__u32 queue_id[3];
+	__u32 reserved;
+};
+
+struct mana_ib_create_wq {
+	__aligned_u64 wq_buf_addr;
+	__u32 wq_buf_size;
+	__u32 reserved;
+};
+
+/* RX Hash function flags */
+enum mana_ib_rx_hash_function_flags {
+	MANA_IB_RX_HASH_FUNC_TOEPLITZ = 1 << 0,
+};
+
+struct mana_ib_create_qp_rss {
+	__aligned_u64 rx_hash_fields_mask;
+	__u8 rx_hash_function;
+	__u8 reserved[7];
+	__u32 rx_hash_key_len;
+	__u8 rx_hash_key[40];
+	__u32 port;
+};
+
+struct rss_resp_entry {
+	__u32 cqid;
+	__u32 wqid;
+};
+
+struct mana_ib_create_qp_rss_resp {
+	__aligned_u64 num_entries;
+	struct rss_resp_entry entries[64];
+};
+
+enum mana_ib_ucontext_support {
+	MANA_IB_UCNTX_ALLOC_PDN_SUPPORT = 1 << 0,
+};
+
+struct mana_ib_alloc_ucontext_resp {
+	__aligned_u64 comp_mask;
+};
+
+enum mana_ib_create_pd_flags {
+	MANA_IB_PD_SHORT_PDN = 1 << 0,
+};
+
+struct mana_ib_alloc_pd {
+	__u32 comp_mask;
+	__u32 reserved;
+};
+
+struct mana_ib_alloc_pd_resp {
+	__u32 pdn;
+	__u32 reserved;
+};
+
+#endif