On 05/27/05 06:45, Jeff Garzik wrote: > Christoph Hellwig wrote: > >>On Fri, May 27, 2005 at 04:37:29AM -0400, Jeff Garzik wrote: >> >> >>>Christoph Hellwig wrote: >>> >>> >>>>You can sleep in them. You must however release the host lock and enable >>>>irqs first and reverse that before returning. The error handlers don't >>>>need the host lock, but we're stuck with the unfortunate calling convention >>>>for now. >>> >>>Why are we stuck with this calling convention, when everyone who cares >>>circumvents it? >> >> >>Because no one found the time to do a full transition yet. If you want to >>update all scsi drivers feel free. One patch per method please. > > > Something like the attached? I like it very, _very_ much. That is, what is the point to have EH in the first place (from a kernel thread) when a lock is held and irqs are off? (no sleeping) Might as well go back to abort()... ;-) The whole point of EH is so that LLDD can sleep waiting possible for TMFs to return. In general I don't like to see SCSI Core imposed locking onto the LLDDs. LLDDs should take care of their own locking as should SCSI Core. Next: off with the host_lock. ;-) > * Returns SUCCESS if command aborted else FAILED > * > - * Locks: struct Scsi_Host::host_lock held (with irqsave) on entry > - * and assumed to be held on return. > + * Locks: None held. EH context. > * > * Calling context: kernel thread Is it possible to mention explicitly that sleeping is allowed and encouraged while waiting for TMFs to return and to change "LLD", "Low Level Driver" -- I've seen those on the streets, either drunks or bad drivers, -- to "LLDD", "Low Level _Device_ Drivers"? Luben - : send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
