qemu

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#include "qemu/osdep.h"
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#include "qemu/units.h"
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#include "qemu/bswap.h"
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#include "hw/scsi/emulation.h"
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int scsi_emulate_block_limits(uint8_t *outbuf, const SCSIBlockLimits *bl)
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{
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    /* required VPD size with unmap support */
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    memset(outbuf, 0, 0x3c);
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    outbuf[0] = bl->wsnz; /* wsnz */
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    if (bl->max_io_sectors) {
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        /* optimal transfer length granularity.  This field and the optimal
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         * transfer length can't be greater than maximum transfer length.
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         */
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        stw_be_p(outbuf + 2, MIN(bl->min_io_size, bl->max_io_sectors));
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        /* maximum transfer length */
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        stl_be_p(outbuf + 4, bl->max_io_sectors);
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        /* optimal transfer length */
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        stl_be_p(outbuf + 8, MIN(bl->opt_io_size, bl->max_io_sectors));
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    } else {
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        stw_be_p(outbuf + 2, bl->min_io_size);
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        stl_be_p(outbuf + 8, bl->opt_io_size);
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    }
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    /* max unmap LBA count */
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    stl_be_p(outbuf + 16, bl->max_unmap_sectors);
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    /* max unmap descriptors */
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    stl_be_p(outbuf + 20, bl->max_unmap_descr);
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    /* optimal unmap granularity; alignment is zero */
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    stl_be_p(outbuf + 24, bl->unmap_sectors);
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    /* max write same size, make it the same as maximum transfer length */
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    stl_be_p(outbuf + 36, bl->max_io_sectors);
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    return 0x3c;
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}
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