Richard Sharpe wrote: > On Mon, Jul 28, 2008 at 7:49 PM, Mark Harvey <[EMAIL PROTECTED]> wrote: >> Richard Sharpe wrote: >>>> From a16d368a29298170df2c21fd19d8490c248f06b1 Mon Sep 17 00:00:00 2001 >>> From: Richard Sharpe <[EMAIL PROTECTED]> >>> Date: Mon, 28 Jul 2008 14:34:12 -0700 >>> Subject: [PATCH] Make changes so that VTL stuff works properly ... >>> Signed-off-by: Richard Sharpe <[EMAIL PROTECTED]> >>> >>> There are three changes here. >>> >>> In target.h I expose device_lookup for use by the smc.c code. >>> >>> In target.h I modify tgt_device_path_update so that we can call it to >>> both open and close a file that has been allocated to a >>> data_transfer_station. >>> >>> In smc.c I modified set_slot_full and set_slot_empty to call the >>> modified tgt_device_path_update to achieve my goals. We call >>> device_lookup to figure out the device we are interested in. >>> >>> I have tested this by loading and unloading tapes and DVDs, doing tar >>> to the drive and using cdrecord on the device, and verifying with lsof >>> that the tgtd has the files open when they are in the transfer station >>> and does not have them open when the station has been unloaded. >>> >>> It all seems to work. I have attached the patch as well because gmail >>> seems to kill patches ... I hope the attached patch is OK. >> Sorry, I don't quite understand the reason for this patch. >> >> The smc already calls a non-static dtd_load_unload() which performs a >> similar function to tgt_device_path_update() but with different args. >> >> int dtd_load_unload(int tid, uint64_t lun, int load, char *file) >> vs >> int tgt_device_path_update(struct target *target, struct scsi_lu *lu, char >> *path) >> >> i.e. dtd_load_unload calls __device_lookup() and then opens/closes the >> backing store. >> >> All this patch seems to do is call the 'open' or 'close' backing store >> twice. >> >> >> Perhaps 'fixing' dtd_load_unload() so it then calls tgt_device_path_update() >> if this function is not correct. >> >> FWIW: dtd_load_unload == Data Transfer Device load/unload >> >> At the time this function was added, the tgt_device_path_update() did not >> exist. > > All I know is that the current code segfaults when you ask for a tape > to be loaded into the transfer station. > > It segfaults because the appropriate bs_open method has not been > called (which initializes some lists and such). > > tgt_device_path_update calls the bs_open routine (through the dev structure) > ...
The initial open should setup/initialise the backing store methods. Once they have been initialised, this should not be required on each media load/unload. Or am I missing something here ? i.e. The init routine(s) should be called at startup/setup time, and the open/close should be called on each media load/unload. Maybe its the ssc is not calling the backing store init correctly at startup ? I'm not in a position to examine the code at the moment - however I'll have a look (tomorrow) also. Please advise if I'm way off course with this - I missed the whole core-dump email thread and need to get up to speed. Cheers Mark > _______________________________________________ > Stgt-devel mailing list > [email protected] > https://lists.berlios.de/mailman/listinfo/stgt-devel > _______________________________________________ Stgt-devel mailing list [email protected] https://lists.berlios.de/mailman/listinfo/stgt-devel
