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Diff for /src/sys/sys/xio.h between versions 1.5 and 1.6

version 1.5, 2004/07/16 05:51:57 version 1.6, 2005/03/01 23:35:16
Line 35 Line 35
  */   */
   
 /*  /*
  * The XIO structure is intended to replace UIO for messaged I/O operations   * An XIO holds a platform-agnostic page list representing a data set for
  * within the kernel.  The originator of the transaction must supply an XIO   * the purposes of I/O, mapping (SFBUF/MSFBUF), or other operations.  The
  * structure containing a list of appropriate held vm_page's representing   * representation of the data set is byte aligned.  xio_offset and xio_bytes
  * the buffer.  The target of the transaction will generally map the   * specifies the precise byte-ranged block within the page list being
  * pages using the SF_BUF facility, complete the operation, and reply the   * represented.
  * message.   *
    * XIOs do not track an ongoing I/O, they simply represent a block of data.
    * For this reason most XIO API functions have a 'uoffset' argument which
    * the caller may use to index within the represented dataset.  This index
    * is relative to the represented dataset, NOT to the beginning of the
    * first page.
  */   */
 #ifndef _SYS_XIO_H_  #ifndef _SYS_XIO_H_
 #define _SYS_XIO_H_  #define _SYS_XIO_H_
Line 70  typedef struct xio *xio_t; Line 75  typedef struct xio *xio_t;
   
 #define XIOF_READ       0x0001  #define XIOF_READ       0x0001
 #define XIOF_WRITE      0x0002  #define XIOF_WRITE      0x0002
 #define XIOF_LINMAP     0x0004  
   
 #endif  #endif
   
Line 80  void xio_init(xio_t xio); Line 84  void xio_init(xio_t xio);
 int xio_init_ubuf(xio_t xio, void *ubase, size_t ubytes, int vmprot);  int xio_init_ubuf(xio_t xio, void *ubase, size_t ubytes, int vmprot);
 int xio_init_kbuf(xio_t xio, void *kbase, size_t kbytes);  int xio_init_kbuf(xio_t xio, void *kbase, size_t kbytes);
 void xio_release(xio_t xio);  void xio_release(xio_t xio);
 int xio_uio_copy(xio_t xio, struct uio *uio, int *sizep);  int xio_uio_copy(xio_t xio, int uoffset, struct uio *uio, int *sizep);
 int xio_copy_xtou(xio_t xio, void *uptr, int bytes);  int xio_copy_xtou(xio_t xio, int uoffset, void *uptr, int bytes);
 int xio_copy_xtok(xio_t xio, void *kptr, int bytes);  int xio_copy_xtok(xio_t xio, int uoffset, void *kptr, int bytes);
   
   /*
    * XIOs are not modified by copy operations, the caller must track the 
    * offset itself.  This routine will return the number of bytes remaining
    * in an XIO's buffer given an offset relative to the buffer used to
    * originally construct the XIO.
    */
   static __inline
   int
   xio_remaining(xio_t xio, int uoffset)
   {
           return(xio->xio_bytes - uoffset);
   }
   
   /*
    * XIOs do not map data but if the page list WERE mapped, this routine will
    * return the actual KVA offset given a user offset relative to the original
    * buffer used to construct the XIO.
    */
   static __inline
   int
   xio_kvaoffset(xio_t xio, int uoffset)
   {
           return(xio->xio_offset + uoffset);
   }
   
 #endif /* _KERNEL */  #endif /* _KERNEL */
   
Removed from v.1.5  
changed lines
  Added in v.1.6