bug in invoking SaveResume device driver command on device driver chain

[Lars Erdmann]

There a a couple of errors in an attempt to send a SaveResume request packet to all device drivers in the device driver chain: For once, the request packet is wrong, additionally the function code 20h (SaveResume) is overwritten with 0 (DEVICE init). See corrections below

file "thunk.asm":

the request packet should look like this:

SRPacket       db  14           ; Size
               db  0            ; Unit
               db  20h          ; Cmd
               dw  0            ; Status
               db  0            ; Flag
               db  0,0,0        ; Reserved
               dd  0            ; Link
               db  0            ; Save/Restore

likewise at label "To16DDNotify"

delete this line:

              mov      Word Ptr es:[bx+3],0

[Lars Erdmann]

routine "SendDDNotify" : maybe it's also a very good idea to call KernSerialize16BitDD/KernUnserialize16BitDD before/after traversing the device driver chain and invoking SaveRestore on each driver. I think that could be necessary for SMP system to properly serialize access to all the device drivers.

[Lars Erdmann]

1.) correction: move Word Ptr es:[bx+3],0 has to stay in. I confused this with the offset for the command code. Nevertheless this call should be moved INSIDE the loop that invokes all device drivers entry points because it might be potentially set by each device driver

2.) maybe this code as a whole is obsolete with newer versions of APM.ADD. Will check

[David Azarewicz]

Milestone eCS 2.x deleted