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path: root/drivers/usb/storage/cypress_atacb.c
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2008-05-02[SCSI] Let scsi_cmnd->cmnd use request->cmd bufferBoaz Harrosh
- struct scsi_cmnd had a 16 bytes command buffer of its own. This is an unnecessary duplication and copy of request's cmd. It is probably left overs from the time that scsi_cmnd could function without a request attached. So clean that up. - Once above is done, few places, apart from scsi-ml, needed adjustments due to changing the data type of scsi_cmnd->cmnd. - Lots of drivers still use MAX_COMMAND_SIZE. So I have left that #define but equate it to BLK_MAX_CDB. The way I see it and is reflected in the patch below is. MAX_COMMAND_SIZE - means: The longest fixed-length (*) SCSI CDB as per the SCSI standard and is not related to the implementation. BLK_MAX_CDB. - The allocated space at the request level - I have audit all ISA drivers and made sure none use ->cmnd in a DMA Operation. Same audit was done by Andi Kleen. (*)fixed-length here means commands that their size can be determined by their opcode and the CDB does not carry a length specifier, (unlike the VARIABLE_LENGTH_CMD(0x7f) command). This is actually not exactly true and the SCSI standard also defines extended commands and vendor specific commands that can be bigger than 16 bytes. The kernel will support these using the same infrastructure used for VARLEN CDB's. So in effect MAX_COMMAND_SIZE means the maximum size command scsi-ml supports without specifying a cmd_len by ULD's Signed-off-by: Boaz Harrosh <bharrosh@panasas.com> Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-04-24USB: mass storage: emulation of sat scsi_pass_thru with ATACBmatthieu castet
I have got a cypress usb-ide bridge and I would like to tune or monitor my disk with tools like hdparm, hddtemp or smartctl. My controller support a way to send raw ATA command to the disk with something call atacb (see http://download.cypress.com.edgesuite.net/design_resources/datasheets/contents/cy7c68300c_8.pdf). Atacb support can be added for each application, but there is some disadvantages : - all application need to be patched - A race is possible if there other accesses, because the emulation can be split in 2 atacb scsi transactions. One for sending the command, one for reading the register (if ck_cond is set). I have implemented the emulation in usb-storage with a special proto_handler, and an unsual entry. Signed-off-by: Matthieu CASTET <castet.matthieu@free.fr> Signed-off-by: Matthew Dharm <mdharm-usb@one-eyed-alien.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>