diff options
author | Christoph Hellwig <hch@lst.de> | 2006-11-04 14:10:55 -0500 |
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committer | James Bottomley <jejb@mulgrave.il.steeleye.com> | 2006-11-15 15:14:20 -0500 |
commit | 3b00315799d78f76531b71435fbc2643cd71ae4c (patch) | |
tree | 82f4041632d24e90c18482ffffa6511207978636 /Documentation/dvb | |
parent | 2dc611de5a3fd955cd0298c50691d4c05046db97 (diff) |
[SCSI] untangle scsi_prep_fn
I wanted to add some BUG checks to scsi_prep_fn to make sure no one
sends us a non-sg command, but this function is a horrible mess.
So I decided to detangle the function and document what the valid
cases are. While doing that I found that REQ_TYPE_SPECIAL commands
aren't used by the SCSI layer anymore and we can get rid of the code
handling them.
The new structure of scsi_prep_fn is:
(1) check if we're allowed to send this command
(2) big switch on cmd_type. For the two valid types call into
a function to set the command up, else error
(3) code to handle error cases
Because FS and BLOCK_PC commands are handled entirely separate after
the patch this introduces a tiny amount of code duplication. This
improves readabiulity though and will help to avoid the bidi command
overhead for FS commands so it's a good thing.
I've tested this on both sata and mptsas.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
Diffstat (limited to 'Documentation/dvb')
0 files changed, 0 insertions, 0 deletions