[ECOS] Thread deadlock in high level disk driver?

[ECOS] Thread deadlock in high level disk driver?

[Davy Wouters Atos (Gmail)]

Hello everyone,

I have found something strange in de High level Disk Driver 
(/packages/io/disk/current/src/disk.c).
I am using this to access the mmc_spi driver and an spi driver I wrote 
myself.
When something goes wrong in the mmc_spi or spi driver, a deadlock occurs 
leaving the disk controller busy.

The functions disk_bread and disk_bwrite contains 'goto done;' statements. 
In the case these goto statements
are executed (probably something wrong in low level driver), the ctrl->busy 
is not cleared to false and any subsequent
calls to the disk driver result in a cyg_drv_cond_wait. (putting the thread 
it's in to sleep)

For now i have patched to code as follows below to prevent this from 
happening.
Maybe this code is intended to lock the disk controller when an error 
occurs?

Any comments anyone?
Tnx,
Kind regards,
Davy Wouters

*** disk.c Wed Dec  1 10:38:15 2010
--- _disk.c Wed Dec  1 10:37:47 2010
***************
*** 560,570 ****
--- 560,576 ----
              cyg_drv_dsr_unlock();

              if (ENOERR != res)
+             {
+     ctlr->busy = false;
+     cyg_drv_cond_signal( &ctlr->queue );
                  goto done;
+             }

              if (!info->connected)
              {
                  res = -EINVAL;
+                 ctlr->busy = false;
+                 cyg_drv_cond_signal( &ctlr->queue );
                  goto done;
              }

***************
*** 636,642 ****
              if (pos > last)
              {
                  res = -EIO;
!                 goto done;
              }

              if( tfr > info->ident.max_transfer )
--- 642,648 ----
              if (pos > last)
              {
                  res = -EIO;
!                 break;
              }

              if( tfr > info->ident.max_transfer )
***************
*** 664,674 ****
--- 670,686 ----
              cyg_drv_dsr_unlock();

              if (ENOERR != res)
+             {
+     ctlr->busy = false;
+     cyg_drv_cond_signal( &ctlr->queue );
                  goto done;
+             }

              if (!info->connected)
+     ctlr->busy = false;
+     cyg_drv_cond_signal( &ctlr->queue );
                  goto done;
              }




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