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Lines 497-503
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| 497 |
char *buf, size_t *rsize) |
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char *buf, size_t *rsize) |
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{ |
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{ |
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struct disk_devdesc *dev = (struct disk_devdesc *)devdata; |
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struct disk_devdesc *dev = (struct disk_devdesc *)devdata; |
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int blks; |
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int blks, remaining; |
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#ifdef BD_SUPPORT_FRAGS /* XXX: sector size */ |
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#ifdef BD_SUPPORT_FRAGS /* XXX: sector size */ |
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char fragbuf[BIOSDISK_SECSIZE]; |
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char fragbuf[BIOSDISK_SECSIZE]; |
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size_t fragsize; |
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size_t fragsize; |
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Lines 513-526
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| 513 |
if (rsize) |
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if (rsize) |
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*rsize = 0; |
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*rsize = 0; |
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if (dblk >= BD(dev).bd_sectors) { |
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/* |
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DEBUG("IO past disk end %llu", (unsigned long long)dblk); |
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* Perform partial read to prevent read-ahead crossing |
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return (EIO); |
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* the end of disk - or any 32 bit aliases of the end. |
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} |
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* Signed arithmetic is used to handle wrap-around cases |
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* like we do for TCP sequence numbers. |
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if (dblk + blks > BD(dev).bd_sectors) { |
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*/ |
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/* perform partial read */ |
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remaining = (int)(BD(dev).bd_sectors - dblk); /* truncate */ |
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blks = BD(dev).bd_sectors - dblk; |
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if (remaining > 0 && remaining < blks) { |
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blks = remaining; |
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size = blks * BD(dev).bd_sectorsize; |
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size = blks * BD(dev).bd_sectorsize; |
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DEBUG("short read %d", blks); |
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DEBUG("short read %d", blks); |
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} |
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} |