get_pktiopb(9f)

1get_pktiopb(9F)          Kernel Functions for Drivers          get_pktiopb(9F)
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NAME

6       get_pktiopb, free_pktiopb - allocate/free a SCSI packet in the iopb map
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SYNOPSIS

9       #include <sys/scsi/scsi.h>
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13       struct scsi_pkt *get_pktiopb(struct scsi_address *ap,
14            caddr_t *datap, int cdblen, int statuslen, int datalen,
15            int readflag, int (*callback);
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18       void free_pktiopb(struct scsi_pkt *pkt, caddr_t datap, int datalen);
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INTERFACE LEVEL

22       These   interfaces   are  obsolete.  Use  scsi_alloc_consistent_buf(9F)
23       instead of get_pktiopb(). Use scsi_free_consistent_buf(9F)  instead  of
24       free_pktiopb().
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PARAMETERS

27       ap           Pointer to the target's scsi_address structure.
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30       datap        Pointer  to  the  address of the packet, set by this func‐
31                    tion.
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34       cdblen       Number of bytes required for the SCSI  command  descriptor
35                    block (CDB).
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38       statuslen    Number of bytes required for the SCSI status area.
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41       datalen      Number  of  bytes  required  for the data area of the SCSI
42                    command.
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45       readflag     If non-zero, data will be transferred from the  SCSI  tar‐
46                    get.
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49       callback     Pointer to a callback function, or NULL_FUNC or SLEEP_FUNC
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52       pkt          Pointer to a scsi_pkt(9S) structure.
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DESCRIPTION

56       The  get_pktiopb()  function  allocates a scsi_pkt structure that has a
57       small data area allocated. It is used by some  SCSI  commands  such  as
58       REQUEST_SENSE,  which involve a small amount of data and require cache-
59       consistent memory for proper operation. It uses ddi_iopb_alloc(9F)  for
60       allocating  the  data area and scsi_resalloc(9F) to allocate the packet
61       and DMA resources.
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64       callback indicates what get_pktiopb() should do when resources are  not
65       available:
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67       NULL_FUNC       Do not wait for resources. Return a NULL pointer.
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70       SLEEP_FUNC      Wait indefinitely for resources.
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73       Other Values    callback  points  to  a  function  which is called when
74                       resources may  have  become  available.  callback  must
75                       return  either 0 (indicating that it attempted to allo‐
76                       cate resources but failed to do  so  again),  in  which
77                       case it is put back on a list to be called again later,
78                       or 1 indicating either success in allocating  resources
79                       or indicating that it no longer cares for a retry.
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83       The  free_pktiopb()  function  is  used  for freeing the packet and its
84       associated resources.
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RETURN VALUES

87       The get_pktiopb() function returns a pointer  to  the  newly  allocated
88       scsi_pkt or a NULL pointer.
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CONTEXT

91       If  callback  is  SLEEP_FUNC, then this routine can be called only from
92       user or kernel context. Otherwise, it can be called from  user,  inter‐
93       rupt, or kernel context. The callback function should not block or call
94       routines that block.
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97       The free_pktiopb() function can be called from user, interrupt, or ker‐
98       nel context.
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ATTRIBUTES

101       See attributes(5) for a description of the following attributes:
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106       ┌─────────────────────────────┬─────────────────────────────┐
107       │      ATTRIBUTE TYPE         │      ATTRIBUTE VALUE        │
108       ├─────────────────────────────┼─────────────────────────────┤
109       │Stability Level              │Obsolete                     │
110       └─────────────────────────────┴─────────────────────────────┘
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NOTES

121       The get_pktiopb() and free_pktiopb() functions are obsolete and will be
122       discontinued in a future release. These functions  have  been  replaced
123       by,  respectively,  scsi_alloc_consistent_buf(9F) and scsi_free_consis‐
124       tent_buf(9F).
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127       The get_pktiopb() function uses scarce resources. For this  reason  and
128       its obsolescence (see above), its use is discouraged.
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132SunOS 5.11                        16 Jan 2006                  get_pktiopb(9F)