qemu

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/*
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 * Block utility functions
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 *
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 * Copyright IBM, Corp. 2011
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 * Copyright (c) 2020 Coiby Xu <coiby.xu@gmail.com>
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 *
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 * This work is licensed under the terms of the GNU GPL, version 2 or later.
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 * See the COPYING file in the top-level directory.
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 */
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#include "qemu/osdep.h"
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#include "qapi/error.h"
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#include "qapi/qmp/qerror.h"
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#include "block-helpers.h"
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/**
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 * check_block_size:
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 * @id: The unique ID of the object
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 * @name: The name of the property being validated
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 * @value: The block size in bytes
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 * @errp: A pointer to an area to store an error
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 *
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 * This function checks that the block size meets the following conditions:
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 * 1. At least MIN_BLOCK_SIZE
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 * 2. No larger than MAX_BLOCK_SIZE
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 * 3. A power of 2
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 */
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void check_block_size(const char *id, const char *name, int64_t value,
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                      Error **errp)
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{
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    /* value of 0 means "unset" */
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    if (value && (value < MIN_BLOCK_SIZE || value > MAX_BLOCK_SIZE)) {
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        error_setg(errp, QERR_PROPERTY_VALUE_OUT_OF_RANGE,
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                   id, name, value, MIN_BLOCK_SIZE, MAX_BLOCK_SIZE);
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        return;
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    }
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    /* We rely on power-of-2 blocksizes for bitmasks */
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    if ((value & (value - 1)) != 0) {
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        error_setg(errp,
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                   "Property %s.%s doesn't take value '%" PRId64
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                   "', it's not a power of 2",
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                   id, name, value);
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        return;
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    }
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}
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