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, 86 insertions, 0 deletions

diff --git a/drivers/md/dm-vdo/status-codes.h b/drivers/md/dm-vdo/status-codes.h
new file mode 100644
index 000000000..426dc8e2c
--- /dev/null
+++ b/drivers/md/dm-vdo/status-codes.h
@@ -0,0 +1,86 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright 2023 Red Hat
+ */
+
+#ifndef VDO_STATUS_CODES_H
+#define VDO_STATUS_CODES_H
+
+#include "errors.h"
+
+enum {
+	UDS_ERRORS_BLOCK_SIZE = UDS_ERROR_CODE_BLOCK_END - UDS_ERROR_CODE_BASE,
+	VDO_ERRORS_BLOCK_START = UDS_ERROR_CODE_BLOCK_END,
+	VDO_ERRORS_BLOCK_END = VDO_ERRORS_BLOCK_START + UDS_ERRORS_BLOCK_SIZE,
+};
+
+/* VDO-specific status codes. */
+enum vdo_status_codes {
+	/* base of all VDO errors */
+	VDO_STATUS_CODE_BASE = VDO_ERRORS_BLOCK_START,
+	/* we haven't written this yet */
+	VDO_NOT_IMPLEMENTED = VDO_STATUS_CODE_BASE,
+	/* input out of range */
+	VDO_OUT_OF_RANGE,
+	/* an invalid reference count would result */
+	VDO_REF_COUNT_INVALID,
+	/* a free block could not be allocated */
+	VDO_NO_SPACE,
+	/* improper or missing configuration option */
+	VDO_BAD_CONFIGURATION,
+	/* prior operation still in progress */
+	VDO_COMPONENT_BUSY,
+	/* page contents incorrect or corrupt data */
+	VDO_BAD_PAGE,
+	/* unsupported version of some component */
+	VDO_UNSUPPORTED_VERSION,
+	/* component id mismatch in decoder */
+	VDO_INCORRECT_COMPONENT,
+	/* parameters have conflicting values */
+	VDO_PARAMETER_MISMATCH,
+	/* no partition exists with a given id */
+	VDO_UNKNOWN_PARTITION,
+	/* a partition already exists with a given id */
+	VDO_PARTITION_EXISTS,
+	/* physical block growth of too few blocks */
+	VDO_INCREMENT_TOO_SMALL,
+	/* incorrect checksum */
+	VDO_CHECKSUM_MISMATCH,
+	/* a lock is held incorrectly */
+	VDO_LOCK_ERROR,
+	/* the VDO is in read-only mode */
+	VDO_READ_ONLY,
+	/* the VDO is shutting down */
+	VDO_SHUTTING_DOWN,
+	/* the recovery journal has corrupt entries or corrupt metadata */
+	VDO_CORRUPT_JOURNAL,
+	/* exceeds maximum number of slabs supported */
+	VDO_TOO_MANY_SLABS,
+	/* a compressed block fragment is invalid */
+	VDO_INVALID_FRAGMENT,
+	/* action is unsupported while rebuilding */
+	VDO_RETRY_AFTER_REBUILD,
+	/* a block map entry is invalid */
+	VDO_BAD_MAPPING,
+	/* bio_add_page failed */
+	VDO_BIO_CREATION_FAILED,
+	/* bad magic number */
+	VDO_BAD_MAGIC,
+	/* bad nonce */
+	VDO_BAD_NONCE,
+	/* sequence number overflow */
+	VDO_JOURNAL_OVERFLOW,
+	/* the VDO is not in a state to perform an admin operation */
+	VDO_INVALID_ADMIN_STATE,
+	/* one more than last error code */
+	VDO_STATUS_CODE_LAST,
+	VDO_STATUS_CODE_BLOCK_END = VDO_ERRORS_BLOCK_END
+};
+
+extern const struct error_info vdo_status_list[];
+
+int vdo_register_status_codes(void);
+
+int vdo_status_to_errno(int error);
+
+#endif /* VDO_STATUS_CODES_H */