1. 22 May, 2009 1 commit
  2. 11 May, 2009 4 commits
    • Tejun Heo's avatar
      block: implement and enforce request peek/start/fetch · 9934c8c0
      Tejun Heo authored
      Till now block layer allowed two separate modes of request execution.
      A request is always acquired from the request queue via
      elv_next_request().  After that, drivers are free to either dequeue it
      or process it without dequeueing.  Dequeue allows elv_next_request()
      to return the next request so that multiple requests can be in flight.
      
      Executing requests without dequeueing has its merits mostly in
      allowing drivers for simpler devices which can't do sg to deal with
      segments only without considering request boundary.  However, the
      benefit this brings is dubious and declining while the cost of the API
      ambiguity is increasing.  Segment based drivers are usually for very
      old or limited devices and as converting to dequeueing model isn't
      difficult, it doesn't justify the API overhead it puts on block layer
      and its more modern users.
      
      Previous patches converted all block low level drivers to dequeueing
      model.  This patch completes the API transition by...
      
      * renaming elv_next_request() to blk_peek_request()
      
      * renaming blkdev_dequeue_request() to blk_start_request()
      
      * adding blk_fetch_request() which is combination of peek and start
      
      * disallowing completion of queued (not started) requests
      
      * applying new API to all LLDs
      
      Renamings are for consistency and to break out of tree code so that
      it's apparent that out of tree drivers need updating.
      
      [ Impact: block request issue API cleanup, no functional change ]
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      Cc: Rusty Russell <rusty@rustcorp.com.au>
      Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
      Cc: Mike Miller <mike.miller@hp.com>
      Cc: unsik Kim <donari75@gmail.com>
      Cc: Paul Clements <paul.clements@steeleye.com>
      Cc: Tim Waugh <tim@cyberelk.net>
      Cc: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
      Cc: David S. Miller <davem@davemloft.net>
      Cc: Laurent Vivier <Laurent@lvivier.info>
      Cc: Jeff Garzik <jgarzik@pobox.com>
      Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
      Cc: Grant Likely <grant.likely@secretlab.ca>
      Cc: Adrian McMenamin <adrian@mcmen.demon.co.uk>
      Cc: Stephen Rothwell <sfr@canb.auug.org.au>
      Cc: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
      Cc: Borislav Petkov <petkovbb@googlemail.com>
      Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
      Cc: Alex Dubov <oakad@yahoo.com>
      Cc: Pierre Ossman <drzeus@drzeus.cx>
      Cc: David Woodhouse <dwmw2@infradead.org>
      Cc: Markus Lidel <Markus.Lidel@shadowconnect.com>
      Cc: Stefan Weinhuber <wein@de.ibm.com>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: Pete Zaitcev <zaitcev@redhat.com>
      Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
      Signed-off-by: default avatarJens Axboe <jens.axboe@oracle.com>
      9934c8c0
    • Tejun Heo's avatar
      mg_disk: dequeue and track in-flight request · 5b36ad60
      Tejun Heo authored
      mg_disk has at most single request in flight per device.  Till now,
      whenever it needs to access the in-flight request it called
      elv_next_request().  This patch makes mg_disk track the in-flight
      request directly using mg_host->req and dequeue it when processing
      starts.
      
      q->queuedata is set to mg_host so that mg_host can be determined
      without fetching request from the queue.
      
      [ Impact: dequeue in-flight request, one elv_next_request() per request ]
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      Cc: unsik Kim <donari75@gmail.com>
      Signed-off-by: default avatarJens Axboe <jens.axboe@oracle.com>
      5b36ad60
    • Tejun Heo's avatar
      mg_disk: fix queue hang / infinite retry on !fs requests · 9a8d23d8
      Tejun Heo authored
      Both request functions in mg_disk simply return when they encounter a
      !fs request, which means the request will never be cleared from the
      queue causing queue hang and indefinite retry of the request.  Fix it.
      
      While at it, flatten condition checks and add unlikely to !fs tests.
      
      [ Impact: fix possible queue hang / infinite retry of !fs requests ]
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      Cc: unsik Kim <donari75@gmail.com>
      Signed-off-by: default avatarJens Axboe <jens.axboe@oracle.com>
      9a8d23d8
    • Tejun Heo's avatar
      block: convert to pos and nr_sectors accessors · 83096ebf
      Tejun Heo authored
      With recent cleanups, there is no place where low level driver
      directly manipulates request fields.  This means that the 'hard'
      request fields always equal the !hard fields.  Convert all
      rq->sectors, nr_sectors and current_nr_sectors references to
      accessors.
      
      While at it, drop superflous blk_rq_pos() < 0 test in swim.c.
      
      [ Impact: use pos and nr_sectors accessors ]
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      Acked-by: default avatarGeert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
      Tested-by: default avatarGrant Likely <grant.likely@secretlab.ca>
      Acked-by: default avatarGrant Likely <grant.likely@secretlab.ca>
      Tested-by: default avatarAdrian McMenamin <adrian@mcmen.demon.co.uk>
      Acked-by: default avatarAdrian McMenamin <adrian@mcmen.demon.co.uk>
      Acked-by: default avatarMike Miller <mike.miller@hp.com>
      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: Eric Moore <Eric.Moore@lsi.com>
      Cc: Alan Stern <stern@rowland.harvard.edu>
      Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
      Cc: Pete Zaitcev <zaitcev@redhat.com>
      Cc: Stephen Rothwell <sfr@canb.auug.org.au>
      Cc: Paul Clements <paul.clements@steeleye.com>
      Cc: Tim Waugh <tim@cyberelk.net>
      Cc: Jeff Garzik <jgarzik@pobox.com>
      Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
      Cc: Alex Dubov <oakad@yahoo.com>
      Cc: David Woodhouse <dwmw2@infradead.org>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: Dario Ballabio <ballabio_dario@emc.com>
      Cc: David S. Miller <davem@davemloft.net>
      Cc: Rusty Russell <rusty@rustcorp.com.au>
      Cc: unsik Kim <donari75@gmail.com>
      Cc: Laurent Vivier <Laurent@lvivier.info>
      Signed-off-by: default avatarJens Axboe <jens.axboe@oracle.com>
      83096ebf
  3. 28 Apr, 2009 7 commits
  4. 27 Apr, 2009 3 commits
    • Tejun Heo's avatar
      block: replace end_request() with [__]blk_end_request_cur() · f06d9a2b
      Tejun Heo authored
      end_request() has been kept around for backward compatibility;
      however, it's about time for it to go away.
      
      * There aren't too many users left.
      
      * Its use of @updtodate is pretty confusing.
      
      * In some cases, newer code ends up using mixture of end_request() and
        [__]blk_end_request[_all](), which is way too confusing.
      
      So, add [__]blk_end_request_cur() and replace end_request() with it.
      Most conversions are straightforward.  Noteworthy ones are...
      
      * paride/pcd: next_request() updated to take 0/-errno instead of 1/0.
      
      * paride/pf: pf_end_request() and next_request() updated to take
        0/-errno instead of 1/0.
      
      * xd: xd_readwrite() updated to return 0/-errno instead of 1/0.
      
      * mtd/mtd_blkdevs: blktrans_discard_request() updated to return
        0/-errno instead of 1/0.  Unnecessary local variable res
        initialization removed from mtd_blktrans_thread().
      
      [ Impact: cleanup ]
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      Acked-by: default avatarJoerg Dorchain <joerg@dorchain.net>
      Acked-by: default avatarGeert Uytterhoeven <geert@linux-m68k.org>
      Acked-by: default avatarGrant Likely <grant.likely@secretlab.ca>
      Acked-by: default avatarLaurent Vivier <Laurent@lvivier.info>
      Cc: Tim Waugh <tim@cyberelk.net>
      Cc: Stephen Rothwell <sfr@canb.auug.org.au>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
      Cc: Markus Lidel <Markus.Lidel@shadowconnect.com>
      Cc: David Woodhouse <dwmw2@infradead.org>
      Cc: Pete Zaitcev <zaitcev@redhat.com>
      Cc: unsik Kim <donari75@gmail.com>
      f06d9a2b
    • Bartlomiej Zolnierkiewicz's avatar
      mg_disk: fix CONFIG_LBD=y warning · 7090a0a9
      Bartlomiej Zolnierkiewicz authored
      drivers/block/mg_disk.c: In function ‘mg_dump_status’:
      drivers/block/mg_disk.c:265: warning: format ‘%ld’ expects type ‘long int’, but
      argument 2 has type ‘sector_t’
      
      [ Impact: kill build warning ]
      
      Cc: unsik Kim <donari75@gmail.com>
      Signed-off-by: default avatarBartlomiej Zolnierkiewicz <bzolnier@gmail.com>
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      7090a0a9
    • Tejun Heo's avatar
      mg_disk: fix locking · ac2ff946
      Tejun Heo authored
      IRQ and timeout handlers call functions which expect locked queue lock
      without locking it.  Fix it.
      
      While at it, convert 0s used as null pointer constant to NULLs.
      
      [ Impact: fix locking, cleanup ]
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      Cc: unsik Kim <donari75@gmail.com>
      ac2ff946
  5. 07 Apr, 2009 1 commit
    • unsik Kim's avatar
      mflash: initial support · 3fbed4c6
      unsik Kim authored
      This driver supports mflash IO mode for linux.
      
      Mflash is embedded flash drive and mainly targeted mobile and consumer
      electronic devices.
      
      Internally, mflash has nand flash and other hardware logics and supports 2
      different operation (ATA, IO) modes.  ATA mode doesn't need any new driver
      and currently works well under standard IDE subsystem.  Actually it's one
      chip SSD.  IO mode is ATA-like custom mode for the host that doesn't have
      IDE interface.
      
      Followings are brief descriptions about IO mode.
      A. IO mode based on ATA protocol and uses some custom command. (read confirm,
      write confirm)
      B. IO mode uses SRAM bus interface.
      C. IO mode supports 4kB boot area, so host can boot from mflash.
      
      This driver is quitely similar to a standard ATA driver, but because of
      following reasons it is currently seperated with ATA layer.
      
      1. ATA layer deals standard ATA protocol.  ATA layer have many low-
         level device specific interface, but data transfer keeps ATA rule.
         But, mflash IO mode doesn't.
      
      2. Even though currently not used in mflash driver code, mflash has
         some custom command and modes.  (nand fusing, firmware patch, etc) If
         this feature supported in linux kernel, ATA layer more altered.
      
      3. Currently PATA platform device driver doesn't support interrupt.
         (I'm not sure) But, mflash uses interrupt (polling mode is just for
         debug).
      
      4. mflash is somewhat under-develop product.  Even though some company
         already using mflash their own product, I think more time is needed for
         standardization of custom command and mode.  That time (maybe October)
         I will talk to with ATA people.  If they accept integration, I will
         integrate.
      Signed-off-by: default avatarunsik Kim <donari75@gmail.com>
      Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarJens Axboe <jens.axboe@oracle.com>
      3fbed4c6