1. 11 May, 2009 1 commit
    • Tejun Heo's avatar
      block: add rq->resid_len · c3a4d78c
      Tejun Heo authored
      rq->data_len served two purposes - the length of data buffer on issue
      and the residual count on completion.  This duality creates some
      headaches.
      
      First of all, block layer and low level drivers can't really determine
      what rq->data_len contains while a request is executing.  It could be
      the total request length or it coulde be anything else one of the
      lower layers is using to keep track of residual count.  This
      complicates things because blk_rq_bytes() and thus
      [__]blk_end_request_all() relies on rq->data_len for PC commands.
      Drivers which want to report residual count should first cache the
      total request length, update rq->data_len and then complete the
      request with the cached data length.
      
      Secondly, it makes requests default to reporting full residual count,
      ie. reporting that no data transfer occurred.  The residual count is
      an exception not the norm; however, the driver should clear
      rq->data_len to zero to signify the normal cases while leaving it
      alone means no data transfer occurred at all.  This reverse default
      behavior complicates code unnecessarily and renders block PC on some
      drivers (ide-tape/floppy) unuseable.
      
      This patch adds rq->resid_len which is used only for residual count.
      
      While at it, remove now unnecessasry blk_rq_bytes() caching in
      ide_pc_intr() as rq->data_len is not changed anymore.
      
      Boaz	: spotted missing conversion in osd
      Sergei	: spotted too early conversion to blk_rq_bytes() in ide-tape
      
      [ Impact: cleanup residual count handling, report 0 resid by default ]
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
      Cc: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
      Cc: Borislav Petkov <petkovbb@googlemail.com>
      Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
      Cc: Mike Miller <mike.miller@hp.com>
      Cc: Eric Moore <Eric.Moore@lsi.com>
      Cc: Alan Stern <stern@rowland.harvard.edu>
      Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
      Cc: Doug Gilbert <dgilbert@interlog.com>
      Cc: Mike Miller <mike.miller@hp.com>
      Cc: Eric Moore <Eric.Moore@lsi.com>
      Cc: Darrick J. Wong <djwong@us.ibm.com>
      Cc: Pete Zaitcev <zaitcev@redhat.com>
      Cc: Boaz Harrosh <bharrosh@panasas.com>
      Signed-off-by: default avatarJens Axboe <jens.axboe@oracle.com>
      c3a4d78c
  2. 12 Mar, 2009 1 commit
  3. 02 Jan, 2009 13 commits
  4. 29 Dec, 2008 13 commits
  5. 21 Oct, 2008 2 commits
  6. 16 Oct, 2008 1 commit
  7. 26 Jul, 2008 2 commits
  8. 20 Jun, 2008 1 commit
  9. 20 May, 2008 1 commit
    • Greg Kroah-Hartman's avatar
      SCSI: fix race in device_create · 24b42566
      Greg Kroah-Hartman authored
      There is a race from when a device is created with device_create() and
      then the drvdata is set with a call to dev_set_drvdata() in which a
      sysfs file could be open, yet the drvdata will be NULL, causing all
      sorts of bad things to happen.
      
      This patch fixes the problem by using the new function,
      device_create_drvdata().  It fixes the problem in all of the scsi
      drivers that need it.
      
      Cc: Kay Sievers <kay.sievers@vrfy.org>
      Cc: Doug Gilbert <dgilbert@interlog.com>
      Cc: James E.J. Bottomley <James.Bottomley@HansenPartnership.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
      24b42566
  10. 22 Apr, 2008 1 commit
  11. 19 Apr, 2008 1 commit
  12. 16 Apr, 2008 1 commit
  13. 07 Apr, 2008 2 commits