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* Allow 'empty' ModeSelect6 tl;dr Treat a computed length of 0 as `has_valid_page_code`. Details: The SRM console (aka 'BIOS') of DEC Alpha sends an empty ModeSelect6 with the following data: ~~~ ModeSelect6, CDB $151000000c00 ~~~ That makes 12 byte(s) as follows ~~~ 0 1 2 3 4 5 6 7 8 9 10 11 00 00 00 08 00 00 00 00 00 00 02 00 ~~~ decoding it (accoring to [1], Section 8.3.3, Table 94) gives us Mode Data Length 0 Medium Type 0 Device-specific 0 Block desc len 8 Density Code 0 Number of blks 0 Reserved 0 Block length 512 `scsi_command_util::ModeSelect` computes ~~~ offset = 4 + buf[3]; ~~~ giving 12 and ~~~ length -= offset; ~~~ giving 0. Thus it never enters the `while` loop and `has_valid_page_code` stays `false`, raising an error. [1] [Small Computer System Interface - 2 rev 10L.pdf](https://dn790004.ca.archive.org/0/items/SCSISpecificationDocumentsSCSIDocuments/Small%20Computer%20System%20Interface%20-%202%20rev%2010L.pdf) Signed-off-by: Klaus Kämpf <kkaempf@gmail.com> * Allow ModeSelect with page code 1 OpenVMS Alpha (the operating system, not the SRM BIOS) uses ModeSelect6 with a page code of 1. The semantics are unknown, just accepting it works for me. Signed-off-by: Klaus Kämpf <kkaempf@gmail.com> * Fix page length computation in ModeSelect tl;dr The 'skip to next ModeSelect page' computation was off-by-one, either not taking the page code itself into account or missing the fact that the page length is given as `n - 1`. Fix: Add 1 to the computed length. Details: OpenVMS Alpha sends a ModeSelect6 as follows ~~~ command: ModeSelect6, CDB $151000001900 payload: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 00 00 00 08 00 00 00 00 00 00 02 00 01 0a 24 00 00 00 00 00 00 00 00 00 00 ~~~ This translates to (accoring to [1], Section 8.3.3) ~~~ Mode Data Length 0 Medium Type 0 Device-specific 0 Block desc len 8 ~~~ with the following offset / length computation _before_ the `while` loop ~~~ offset = 12 length = 13 ~~~ The first payload section is ~~~ 4 5 6 7 8 9 10 11 00 00 00 00 00 00 02 00 ~~~ translating to ~~~ Density Code 0 Number of blks 0 Reserved 0 Block length 0x200 512 ~~~ Then follows a pagecode 1 as ~~~ 12 13 14 15 16 17 18 19 20 21 22 23 24 01 0a 24 00 00 00 00 00 00 00 00 00 00 ~~~ translating to ~~~~ Page code 1 Page length -1 10 Mode parameters 24 00 00 00 00 00 00 00 00 00 00 ~~~ computing (inside the `while` loop, as `// Advance to the next page`) ~~~ size = 10 + 2 = 12 ~~~ followed by new `offset` and `length` values ~~~ offset = 25 length = 1 ~~~ So it stays in the `while` loop (and has a larger-than-buffer `offset` value) Signed-off-by: Klaus Kämpf <kkaempf@gmail.com> |
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| controllers | ||
| devices | ||
| hal | ||
| piscsi | ||
| scsictl | ||
| scsidump | ||
| scsiloop | ||
| scsimon | ||
| shared | ||
| test | ||
| .gitignore | ||
| Makefile | ||
| piscsi_interface.proto | ||