d48d0fb1bb
the kernel), which encapsulates the information needed to refer to an external buffer. Under normal operation, this can just be a void * equivalent, but under -DKEEP_IT_REAL it would be a segoff_t equivalent. Use this concept to avoid the need for bounce buffers in int13.c, which reduces memory usage and opens up the possibility of using multi-sector reads. Extend the block-device API and the SCSI block device implementation to support multi-sector reads. Update iscsi.c to use user buffers. Move the obsolete portions of realmode.h to old_realmode.h. MS-DOS now boots an order of magnitude faster over iSCSI (~10 seconds from power-up to C:> prompt in bochs).
25 lines
750 B
C
25 lines
750 B
C
#ifndef _GPXE_UACCESS_H
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#define _GPXE_UACCESS_H
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/**
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* @file
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*
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* Access to external ("user") memory
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*
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* gPXE often needs to transfer data between internal and external
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* buffers. On i386, the external buffers may require access via a
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* different segment, and the buffer address cannot be encoded into a
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* simple void * pointer. The @c userptr_t type encapsulates the
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* information needed to identify an external buffer, and the
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* copy_to_user() and copy_from_user() functions provide methods for
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* transferring data between internal and external buffers.
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*
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* Note that userptr_t is an opaque type; in particular, performing
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* arithmetic upon a userptr_t is not allowed.
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*
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*/
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#include <bits/uaccess.h>
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#endif /* _GPXE_UACCESS_H */
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