Commit Graph

287 Commits

Author SHA1 Message Date
Alexey Dobriyan
83d5cde47d const: make block_device_operations const
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-22 07:17:25 -07:00
Alexey Dobriyan
6d703a81ad ide: convert to ->proc_fops
->read_proc, ->write_proc are going away, ->proc_fops should be used instead.

The only tricky place is IDENTIFY handling: if for some reason
taskfile_lib_get_identify() fails, buffer _is_ changed and at least
first byte is overwritten. Emulate old behaviour with returning
that first byte to userspace and reporting length=1 despite overall -E.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-09-01 17:52:57 -07:00
Borislav Petkov
6f3848ac23 ide-tape: fix handling of postponed rqs
ide-tape used to hit

[   58.614854] ide-tape: ht0: BUG: Two DSC requests queued!

due to the fact that another rq was being issued while the driver was
waiting for DSC to get set for the device executing ATAPI commands which
set the DSC to 1 to indicate completion.

Here's a sample output of that case:

issue REZERO_UNIT

[  143.088505] ide-tape: ide_tape_issue_pc: retry #0, cmd: 0x01
[  143.095122] ide: Enter ide_pc_intr - interrupt handler
[  143.096118] ide: Packet command completed, 0 bytes transferred
[  143.106319] ide-tape: ide_tape_callback: cmd: 0x1, dsc: 1, err: 0
[  143.112601] ide-tape: idetape_postpone_request: cmd: 0x1, dsc_poll_freq: 2000

we stall the ide-tape queue here waiting for DSC

[  143.119936] ide-tape: ide_tape_read_position: enter
[  145.119019] ide-tape: idetape_do_request: sector: 4294967295, nr_sectors: 0

and issue the new READ_POSITION rq and hit the check.

[  145.126247] ide-tape: ht0: BUG: Two DSC requests queued!
[  145.131748] ide-tape: ide_tape_read_position: BOP - No
[  145.137059] ide-tape: ide_tape_read_position: EOP - No

Also, ->postponed_rq used to point to that postponed request. To make
things worse, in certain circumstances the rq it was pointing to got
replaced unterneath it by swiftly reusing the same rq from the mempool
of the block layer practically confusing stuff even more.

However, we don't need to keep a pointer to that rq but simply wait for
DSC to be set first before issuing the follow-up request in the drive's
queue. In order to do that, we make idetape_do_request() first check the
DSC and if not set, we stall the drive queue giving the other device on
that IDE channel a chance.

Signed-off-by: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-07 10:42:57 -07:00
Borislav Petkov
e972d7027c ide-tape: convert to ide_debug_log macro
Remove tape->debug_mask and use drive->debug_mask instead.

There should be no functional change resulting from this patch.

Signed-off-by: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-07 10:42:57 -07:00
Mark de Wever
37bbe084d1 ide-tape: fix debug call
This error only occurs when IDETAPE_DEBUG_LOG is enabled.

Signed-off-by: Mark de Wever <koraq@xs4all.nl>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-07 10:42:56 -07:00
Michael Buesch
2fc2111c27 ide-tape: Don't leak kernel stack information
Don't leak kernel stack information through uninitialized structure members.

Signed-off-by: Michael Buesch <mb@bu3sch.de>
Acked-by: Borislav Petkov <petkovbb@gmail.com>.
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-07-21 20:36:25 -07:00
Bartlomiej Zolnierkiewicz
2c7eaa43c3 ide: BUG() on unknown requests
Unsupported requests should be never handed down to device drivers
and the best thing we can do upon discovering such request inside
driver's ->do_request method is to just BUG().

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-06-15 22:16:10 +02:00
Borislav Petkov
79ca743f68 ide-tape: fix build issue
This fixes

drivers/ide/ide-tape.c: In function `idetape_chrdev_open':
drivers/ide/ide-tape.c:1515: error: implicit declaration of function `idetape_read_position'
make[1]: *** [drivers/ide/ide-tape.o] Error 1

Signed-off-by: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-06-15 18:52:52 +02:00
Bartlomiej Zolnierkiewicz
8dcce40813 Merge branch 'bp-remove-pc-buf' into for-next
Conflicts:
	drivers/ide/ide-tape.c
2009-06-13 12:00:54 +02:00
Linus Torvalds
d614aec475 Merge branch 'for-2.6.31' of git://git.kernel.org/pub/scm/linux/kernel/git/bart/ide-2.6
* 'for-2.6.31' of git://git.kernel.org/pub/scm/linux/kernel/git/bart/ide-2.6: (29 commits)
  ide: re-implement ide_pci_init_one() on top of ide_pci_init_two()
  ide: unexport ide_find_dma_mode()
  ide: fix PowerMac bootup oops
  ide: skip probe if there are no devices on the port (v2)
  sl82c105: add printk() logging facility
  ide-tape: fix proc warning
  ide: add IDE_DFLAG_NIEN_QUIRK device flag
  ide: respect quirk_drives[] list on all controllers
  hpt366: enable all quirks for devices on quirk_drives[] list
  hpt366: sync quirk_drives[] list with pdc202xx_{new,old}.c
  ide: remove superfluous SELECT_MASK() call from do_rw_taskfile()
  ide: remove superfluous SELECT_MASK() call from ide_driveid_update()
  icside: remove superfluous ->maskproc method
  ide-tape: fix IDE_AFLAG_* atomic accesses
  ide-tape: change IDE_AFLAG_IGNORE_DSC non-atomically
  pdc202xx_old: kill resetproc() method
  pdc202xx_old: don't call pdc202xx_reset() on IRQ timeout
  pdc202xx_old: use ide_dma_test_irq()
  ide: preserve Host Protected Area by default (v2)
  ide-gd: implement block device ->set_capacity method (v2)
  ...
2009-06-12 09:29:42 -07:00
Linus Torvalds
c9059598ea Merge branch 'for-2.6.31' of git://git.kernel.dk/linux-2.6-block
* 'for-2.6.31' of git://git.kernel.dk/linux-2.6-block: (153 commits)
  block: add request clone interface (v2)
  floppy: fix hibernation
  ramdisk: remove long-deprecated "ramdisk=" boot-time parameter
  fs/bio.c: add missing __user annotation
  block: prevent possible io_context->refcount overflow
  Add serial number support for virtio_blk, V4a
  block: Add missing bounce_pfn stacking and fix comments
  Revert "block: Fix bounce limit setting in DM"
  cciss: decode unit attention in SCSI error handling code
  cciss: Remove no longer needed sendcmd reject processing code
  cciss: change SCSI error handling routines to work with interrupts enabled.
  cciss: separate error processing and command retrying code in sendcmd_withirq_core()
  cciss: factor out fix target status processing code from sendcmd functions
  cciss: simplify interface of sendcmd() and sendcmd_withirq()
  cciss: factor out core of sendcmd_withirq() for use by SCSI error handling code
  cciss: Use schedule_timeout_uninterruptible in SCSI error handling code
  block: needs to set the residual length of a bidi request
  Revert "block: implement blkdev_readpages"
  block: Fix bounce limit setting in DM
  Removed reference to non-existing file Documentation/PCI/PCI-DMA-mapping.txt
  ...

Manually fix conflicts with tracing updates in:
	block/blk-sysfs.c
	drivers/ide/ide-atapi.c
	drivers/ide/ide-cd.c
	drivers/ide/ide-floppy.c
	drivers/ide/ide-tape.c
	include/trace/events/block.h
	kernel/trace/blktrace.c
2009-06-11 11:10:35 -07:00
Borislav Petkov
9d01e4cd7e ide-tape: fix proc warning
ide_tape_chrdev_get() was missing an ide_device_get() refcount increment
which lead to the following warning:

[  278.147906] ------------[ cut here ]------------
[  278.152685] WARNING: at fs/proc/generic.c:847 remove_proc_entry+0x199/0x1b8()
[  278.160070] Hardware name: P4I45PE    1.00
[  278.160076] remove_proc_entry: removing non-empty directory 'ide0/hdb', leaking at least 'name'
[  278.160080] Modules linked in: rtc intel_agp pcspkr thermal processor thermal_sys parport_pc parport agpgart button
[  278.160100] Pid: 2312, comm: mt Not tainted 2.6.30-rc2 #3
[  278.160105] Call Trace:
[  278.160117]  [<c012141d>] warn_slowpath+0x71/0xa0
[  278.160126]  [<c035f219>] ? _spin_unlock_irqrestore+0x29/0x2c
[  278.160132]  [<c011c686>] ? try_to_wake_up+0x1b6/0x1c0
[  278.160141]  [<c011c69b>] ? default_wake_function+0xb/0xd
[  278.160149]  [<c0177ead>] ? pollwake+0x4a/0x55
[  278.160156]  [<c035f240>] ? _spin_unlock+0x24/0x26
[  278.160163]  [<c0165d38>] ? add_partial+0x44/0x49
[  278.160169]  [<c01669e8>] ? __slab_free+0xba/0x29c
[  278.160177]  [<c01a13d8>] ? sysfs_delete_inode+0x0/0x3c
[  278.160184]  [<c019ca92>] remove_proc_entry+0x199/0x1b8
[  278.160191]  [<c01a297e>] ? remove_dir+0x27/0x2e
[  278.160199]  [<c025f3ab>] ide_proc_unregister_device+0x40/0x4c
[  278.160207]  [<c02599cd>] drive_release_dev+0x14/0x47
[  278.160214]  [<c0250538>] device_release+0x35/0x5a
[  278.160221]  [<c01f8bed>] kobject_release+0x40/0x50
[  278.160226]  [<c01f8bad>] ? kobject_release+0x0/0x50
[  278.160232]  [<c01f96ac>] kref_put+0x3c/0x4a
[  278.160238]  [<c01f8b29>] kobject_put+0x37/0x3c
[  278.160243]  [<c025020c>] put_device+0xf/0x11
[  278.160249]  [<c025789f>] ide_device_put+0x2d/0x30
[  278.160255]  [<c02658da>] ide_tape_put+0x24/0x32
[  278.160261]  [<c0266e0c>] idetape_chrdev_release+0x17f/0x18e
[  278.160269]  [<c016c4f5>] __fput+0xca/0x175
[  278.160275]  [<c016c5b9>] fput+0x19/0x1b
[  278.160280]  [<c0169d19>] filp_close+0x51/0x5b
[  278.160286]  [<c0169d96>] sys_close+0x73/0xad
[  278.160293]  [<c0102a61>] syscall_call+0x7/0xb
[  278.160298] ---[ end trace f16d907ea1f89336 ]---

Instead of trivially fixing it by adding the missing call,
ide_tape_chrdev_get() and ide_tape_get() were merged into one function
since both were almost identical. The only difference was that
ide_tape_chrdev_get() was accessing the ide-tape reference through the
idetape_devs[] array of minors instead of through the gendisk.

Accomodate that by adding two additional parameters to ide_tape_get() to
annotate the call site and invoke the proper behavior.

As a result, remove ide_tape_chrdev_get().

Signed-off-by: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-06-08 22:03:03 +02:00
Borislav Petkov
49d8078ad1 ide-tape: fix IDE_AFLAG_* atomic accesses
These flags used to be bit numbers and now are single bits in the
->atapi_flags vector. Use them properly.

Spotted-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-06-07 15:37:06 +02:00
Borislav Petkov
626542ca22 ide-tape: change IDE_AFLAG_IGNORE_DSC non-atomically
There are two sites where the flag is being changed: ide_retry_pc
and idetape_do_request. Both codepaths are protected by hwif->busy
(ide_lock_port) and therefore we shouldn't need the atomic accesses.

Spotted-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-06-07 15:37:05 +02:00
Tejun Heo
5f49f63178 block: set rq->resid_len to blk_rq_bytes() on issue
In commit c3a4d78c58, while introducing
rq->resid_len, the default value of residue count was changed from
full count to zero.  The conversion was done under the assumption that
when a request fails residue count wasn't defined.  However, Boaz and
James pointed out that this wasn't true and the residue count should
be preserved for failed requests too.

This patchset restores the original behavior by setting rq->resid_len
to blk_rq_bytes(rq) on request start and restoring explicit clearing
in affected drivers.  While at it, take advantage of the fact that
rq->resid_len is set to full count where applicable.

* ide-cd: rq->resid_len cleared on pc success

* mptsas: req->resid_len cleared on success

* sas_expander: rsp/req->resid_len cleared on success

* mpt2sas_transport: req->resid_len cleared on success

* ide-cd, ide-tape, mptsas, sas_host_smp, mpt2sas_transport, ub: take
  advantage of initial full count to simplify code

Boaz Harrosh spotted bug in resid_len initialization.  Fixed as
suggested.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Borislav Petkov <petkovbb@googlemail.com>
Cc: Boaz Harrosh <bharrosh@panasas.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Pete Zaitcev <zaitcev@redhat.com>
Cc: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: Eric Moore <Eric.Moore@lsi.com>
Cc: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-19 11:36:08 +02:00
Mark de Wever
e8e7526c3c ide-tape: fix debug call
This error only occurs when IDETAPE_DEBUG_LOG is enabled.

Signed-off-by: Mark de Wever <koraq@xs4all.nl>
Signed-off-by: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-05-17 17:22:53 +02:00
Borislav Petkov
19f52a784f ide-atapi: remove pc->buf
Now after all users of pc->buf have been converted, remove the 64B buffer
embedded in each packet command.

There should be no functional change resulting from this patch.

Signed-off-by: Borislav Petkov <petkovbb@gmail.com>
2009-05-15 06:44:38 +02:00
Borislav Petkov
55ce3a129e ide-tape: fix READ POSITION cmd handling
ide-tape used to issue READ POSITION in several places and the
evaluation of the returned READ POSITION data was done in the
->pc_callback. Convert it to use local buffer and move that
evaluation chunk in the idetape_read_position(). Additionally, fold
idetape_create_read_position_cmd() into it, too, thus concentrating READ
POSITION handling in one method only and making all places call that.

Finally, mv {idetape,ide_tape}_read_position.

There should be no functional change resulting from this patch.

Signed-off-by: Borislav Petkov <petkovbb@gmail.com>
2009-05-15 06:44:35 +02:00
Borislav Petkov
837272b4f9 ide-tape/ide_tape_get_bsize_from_bdesc: use local buffer
There should be no functional change resulting from this patch.

Signed-off-by: Borislav Petkov <petkovbb@gmail.com>
2009-05-15 06:44:31 +02:00
Borislav Petkov
ae3a8387be ide-atapi: use local sense buffer
Access the sense buffer through the bio in ->pc_callback method thus
alleviating the need for the pc->buf pointer.

There should be no functional change resulting from this patch.

Signed-off-by: Borislav Petkov <petkovbb@gmail.com>
2009-05-15 06:44:23 +02:00
Borislav Petkov
b13345f39d ide-atapi: add a buffer-arg to ide_queue_pc_tail
This is in preparation of removing ide_atapi_pc. Expose the buffer as an
argument to ide_queue_pc_tail with later replacing it with local buffer
or even kmalloc'ed one if needed due to stack usage constraints.

Also, add the possibility of passing a NULL-ptr buffer for cmds which
don't transfer data besides the cdb. While at it, switch to local buffer
in idetape_get_mode_sense_results().

There should be no functional change resulting from this patch.

Signed-off-by: Borislav Petkov <petkovbb@gmail.com>
2009-05-15 06:44:09 +02:00
Borislav Petkov
5a0e43b5e2 ide-atapi: add a len-parameter to ide_queue_pc_tail
This is in preparation for removing ide_atapi_pc.

There should be no functional change resulting from this patch.

Signed-off-by: Borislav Petkov <petkovbb@gmail.com>
2009-05-15 06:44:06 +02:00
Borislav Petkov
077e6dba20 ide-atapi: switch to rq->resid_len
Now that we have rq->resid_len, use it to account partial completion
amount during the lifetime of an rq, decrementing it on each successful
transfer. As a result, get rid of now unused pc->xferred.

While at it, remove noisy debug call in ide_prep_sense.

Signed-off-by: Borislav Petkov <petkovbb@gmail.com>
2009-05-15 06:44:02 +02:00
Borislav Petkov
dfb7e621fa ide-atapi: switch to blk_rq_bytes() on do_request() path
After the recent struct request cleanups, blk_rq_bytes() is guaranteed
to be valid and is the current total length of the rq's bio. Use that
instead of pc->req_xfer in the do_request() path after the command has
been queued

The remaining usage of pc->req_xfer now is only until we map the rq to a
bio.

While at it:

- remove local caching of rq completion length in ide_tape_issue_pc()

Signed-off-by: Borislav Petkov <petkovbb@gmail.com>
2009-05-15 06:43:59 +02:00
Borislav Petkov
10c0b3437c ide-tape: fix potential fs requests bug
ide-tape had a potential bug for fs requests when preparing the command
packet: it was writing the transfer length as a number of fixed blocks.
However, the block layer implies 512 byte blocks and ide-tape can have
other block sizes so account for that too.

ide-floppy does this calculation properly with the block size factor
(floppy->bs_factor).

Signed-off-by: Borislav Petkov <petkovbb@gmail.com>
2009-05-15 06:43:45 +02:00
Tejun Heo
34b7d2c957 ide: cleanup rq->data_len usages
With recent unification of fields, it's now guaranteed that
rq->data_len always equals blk_rq_bytes().  Convert all direct users
to accessors.

[ Impact: convert direct rq->data_len usages to blk_rq_bytes() ]

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Cc: Borislav Petkov <petkovbb@googlemail.com>
Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-11 09:50:55 +02:00
Tejun Heo
9780e2dd82 ide: convert to rq pos and nr_sectors accessors
ide doesn't manipulate request fields anymore and thus all hard and
their soft equivalents are always equal.  Convert all references to
accessors.

[ Impact: use pos and nr_sectors accessors ]

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Cc: Borislav Petkov <petkovbb@googlemail.com>
Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-11 09:50:54 +02:00
Tejun Heo
c3a4d78c58 block: add rq->resid_len
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: Tejun 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: Jens Axboe <jens.axboe@oracle.com>
2009-05-11 09:50:53 +02:00
Tejun Heo
9720aef253 ide-tape: don't initialize rq->sector for rw requests
rq->sector is set to the tape->first_frame but it's never actually
used and not even in the correct unit (512 byte sectors).  Don't set
it.

[ Impact: cleanup ]

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Borislav Petkov <petkovbb@gmail.com>
Acked-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-11 09:50:53 +02:00
Tejun Heo
29d1a43710 ide-atapi: kill unused fields and callbacks
Impact: remove fields and code paths which are no longer necessary

Now that ide-tape uses standard mechanisms to transfer data, special
case handling for bh handling can be dropped from ide-atapi.  Drop the
followings.

* pc->cur_pos, b_count, bh and b_data
* drive->pc_update_buffers() and pc_io_buffers().

Signed-off-by: Tejun Heo <tj@kernel.org>
2009-04-28 07:37:32 +02:00
Tejun Heo
4344d07fb8 ide-tape: simplify read/write functions
Impact: cleanup

idetape_chrdev_read/write() functions are unnecessarily complex when
everything can be handled in a single loop.  Collapse
idetape_add_chrdev_read/write_request() into the rw functions and
simplify the implementation.

Signed-off-by: Tejun Heo <tj@kernel.org>
2009-04-28 07:37:32 +02:00
Tejun Heo
71294cf93d ide-tape: use byte size instead of sectors on rw issue functions
Impact: cleanup

Byte size is what most issue functions deal with, make
idetape_queue_rw_tail() and its wrappers take byte size instead of
sector counts.  idetape_chrdev_read() and write() functions are
converted to use tape->buffer_size instead of ctl from tape->cap.

This cleans up code a little bit and will ease the next r/w
reimplementation.

Signed-off-by: Tejun Heo <tj@kernel.org>
2009-04-28 07:37:32 +02:00
Tejun Heo
3596b66452 ide-tape: unify r/w init paths
Impact: cleanup

Read and write init paths are almost identical.  Unify them into
idetape_init_rw().

Signed-off-by: Tejun Heo <tj@kernel.org>
2009-04-28 07:37:32 +02:00
Tejun Heo
6cf3d545f7 ide-tape: kill idetape_bh
Impact: kill now unnecessary idetape_bh

With everything using standard mechanisms, there is no need for
idetape_bh anymore.  Kill it and use tape->buf, cur and valid to
describe data buffer instead.

Changes worth mentioning are...

* idetape_queue_rq_tail() now always queue tape->buf and and adjusts
  buffer state properly before completion.

* idetape_pad_zeros() clears the buffer only once.

Signed-off-by: Tejun Heo <tj@kernel.org>
2009-04-28 07:37:31 +02:00
Tejun Heo
e998f30b45 ide-tape: use standard data transfer mechanism
Impact: use standard way to transfer data

ide-tape uses rq in an interesting way.  For r/w requests, rq->special
is used to carry a private buffer management structure idetape_bh and
rq->nr_sectors and current_nr_sectors are initialized to the number of
idetape blocks which isn't necessary 512 bytes.  Also,
rq->current_nr_sectors is used to report back the residual count in
units of idetape blocks.

This peculiarity taxes both block layer and ide.  ide-atapi has
different paths and hooks to accomodate it and what a rq means becomes
quite confusing and making changes at the block layer becomes quite
difficult and error-prone.

This patch makes ide-tape use bio instead.  With the previous patch,
ide-tape currently is using single contiguos buffer so replacing it
isn't difficult.  Data buffer is mapped into bio using
blk_rq_map_kern() in idetape_queue_rw_tail().  idetape_io_buffers()
and idetape_update_buffers() are dropped and pc->bh is set to null to
tell ide-atapi to use standard data transfer mechanism and idetape_bh
byte counts are updated by the issuer on completion using the residual
count.

This change also nicely removes the FIXME in ide_pc_intr() where
ide-tape rqs need to be completed using ide_rq_bytes() instead of
blk_rq_bytes() (although this didn't really matter as the request
didn't have bio).

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <jens.axboe@oracle.com>
2009-04-28 07:37:31 +02:00
Tejun Heo
7b13354eea ide-tape: use single continuous buffer
Impact: simpler buffer allocation and handling, kills OOM, fix DMA transfers

ide-tape has its own multiple buffer mechanism using struct
idetape_bh.  It allocates buffer with decreasing order-of-two
allocations so that it results in minimum number of segments.
However, the implementation is quite complex and works in a way that
no other block or ide driver works necessitating a lot of special case
handling.

The benefit this complex allocation scheme brings is questionable as
PIO or DMA the number of segments (16 maximum) doesn't make any
noticeable difference and it also doesn't negate the need for multiple
order allocation which can fail under memory pressure or high
fragmentation although it does lower the highest order necessary by
one when the buffer size isn't power of two.

As the first step to remove the custom buffer management, this patch
makes ide-tape allocate single continous buffer.  The maximum order is
four.  I doubt the change would cause any trouble but if it ever
matters, it should be converted to regular sg mechanism like everyone
else and even in that case dropping custom buffer handling and moving
to standard mechanism first make sense as an intermediate step.

This patch makes the first bh to contain the whole buffer and drops
multi bh handling code.  Following patches will make further changes.

This patch has the side effect of killing OOM triggered by allocation
path and fixing DMA transfers.  Previously, bug in alloc path
triggered OOM on command issue and commands were passed to DMA engine
without DMA-mapping all the segments.

Signed-off-by: Tejun Heo <tj@kernel.org>
2009-04-28 07:37:31 +02:00
Tejun Heo
eb6a61bb95 ide-atapi,tape,floppy: allow ->pc_callback() to change rq->data_len
Impact: allow residual count implementation in ->pc_callback()

rq->data_len has two duties - carrying the number of input bytes on
issue and carrying residual count back to the issuer on completion.
ide-atapi completion callback ->pc_callback() is the right place to do
this but currently ide-atapi depends on rq->data_len carrying the
original request size after calling ->pc_callback() to complete the pc
request.

This patch makes ide_pc_intr(), ide_tape_issue_pc() and
ide_floppy_issue_pc() cache length to complete before calling
->pc_callback() so that it can modify rq->data_len as necessary.

Note: As using rq->data_len for two purposes can make cases like this
      incorrect in subtle ways, future changes will introduce separate
      field for residual count.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <jens.axboe@oracle.com>
2009-04-28 07:37:31 +02:00
Tejun Heo
08f370f0a2 ide-tape,floppy: fix failed command completion after request sense
Impact: fix infinite retry loop

After a command failed, ide-tape and floppy inserts REQUEST_SENSE in
front of the failed command and according to the result, sets
pc->retries, flags and errors.  After REQUEST_SENSE is complete, the
failed command is again at the front of the queue and if the verdict
was to terminate the request, the issue functions tries to complete it
directly by calling drive->pc_callback() and returning ide_stopped.

However, drive->pc_callback() doesn't complete a request.  It only
prepares for completion of the request.  As a result, this creates an
infinite loop where the failed request is retried perpetually.

Fix it by actually ending the request by calling ide_complete_rq().

Signed-off-by: Tejun Heo <tj@kernel.org>
2009-04-28 07:37:31 +02:00
Tejun Heo
02e7cf8f84 ide-cd,atapi: use bio for internal commands
Impact: unify request data buffer handling

rq->data is used mostly to pass kernel buffer through request queue
without using bio.  There are only a couple of places which still do
this in kernel and converting to bio isn't difficult.

This patch converts ide-cd and atapi to use bio instead of rq->data
for request sense and internal pc commands.  With previous change to
unify sense request handling, this is relatively easily achieved by
adding blk_rq_map_kern() during sense_rq prep and PC issue.

If blk_rq_map_kern() fails for sense, the error is deferred till sense
issue and aborts the failed command which triggered the sense.  Note
that this is a slim possibility as sense prep is done on each command
issue, so for the above condition to actually trigger, all preps since
the last sense issue till the issue of the request which would require
a sense should fail.

* do_request functions might sleep now.  This should be okay as ide
  request_fn - do_ide_request() - is invoked only from make_request
  and plug work.  Make sure this is the case by adding might_sleep()
  to do_ide_request().

* Functions which access the read sense data before the sense request
  is complete now should access bio_data(sense_rq->bio) as the sense
  buffer might have been copied during blk_rq_map_kern().

* ide-tape updated to map sg.

* cdrom_do_block_pc() now doesn't have to deal with REQ_TYPE_ATA_PC
  special case.  Simplified.

* tp_ops->output/input_data path dropped from ide_pc_intr().

Signed-off-by: Tejun Heo <tj@kernel.org>
2009-04-28 07:37:30 +02:00
Borislav Petkov
068753203e ide-atapi: convert ide-{floppy,tape} to using preallocated sense buffer
Since we're issuing REQ_TYPE_SENSE now we need to allow those types of
rqs in the ->do_request callbacks. As a future improvement, sense_len
assignment might be unified across all ATAPI devices. Borislav to
check with specs and test.

As a result, get rid of ide_queue_pc_head() and
drive->request_sense_rq.

tj: * Init request sense ide_atapi_pc from sense request.  In the
      longer timer, it would probably better to fold
      ide_create_request_sense_cmd() into its only current user -
      ide_floppy_get_format_progress().

    * ide_retry_pc() no longer takes @disk.

CC: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
CC: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2009-04-28 07:37:30 +02:00
Tejun Heo
ac0b0113dd ide-atapi: don't abuse rq->buffer
Impact: rq->buffer usage cleanup

ide-atapi uses rq->buffer as private opaque value for internal special
requests.  rq->special isn't used for these cases (the only case where
rq->special is used is for ide-tape rw requests).  Use rq->special
instead.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
2009-04-28 07:37:29 +02:00
Tejun Heo
0de57fb93b ide-tape: remove back-to-back REQUEST_SENSE detection
Impact: fix an oops which always triggers

ide_tape_issue_pc() assumed drive->pc isn't NULL on invocation when
checking for back-to-back request sense issues but drive->pc can be
NULL and even when it's not NULL, it's not safe to dereference it once
the previous command is complete because pc could have been freed or
was on stack.  Kill back-to-back REQUEST_SENSE detection.

Signed-off-by: Tejun Heo <tj@kernel.org>
2009-04-28 07:37:28 +02:00
Tejun Heo
6d7003877c ide-atapi: kill unused fields and callbacks
Impact: remove fields and code paths which are no longer necessary

Now that ide-tape uses standard mechanisms to transfer data, special
case handling for bh handling can be dropped from ide-atapi.  Drop the
followings.

* pc->cur_pos, b_count, bh and b_data
* drive->pc_update_buffers() and pc_io_buffers().

Signed-off-by: Tejun Heo <tj@kernel.org>
2009-04-19 08:46:03 +09:00
Tejun Heo
07bd9686c5 ide-tape: simplify read/write functions
Impact: cleanup

idetape_chrdev_read/write() functions are unnecessarily complex when
everything can be handled in a single loop.  Collapse
idetape_add_chrdev_read/write_request() into the rw functions and
simplify the implementation.

Signed-off-by: Tejun Heo <tj@kernel.org>
2009-04-19 08:46:03 +09:00
Tejun Heo
6bb11dd14f ide-tape: use byte size instead of sectors on rw issue functions
Impact: cleanup

Byte size is what most issue functions deal with, make
idetape_queue_rw_tail() and its wrappers take byte size instead of
sector counts.  idetape_chrdev_read() and write() functions are
converted to use tape->buffer_size instead of ctl from tape->cap.

This cleans up code a little bit and will ease the next r/w
reimplementation.

Signed-off-by: Tejun Heo <tj@kernel.org>
2009-04-19 08:46:03 +09:00
Tejun Heo
88f1b941c5 ide-tape: unify r/w init paths
Impact: cleanup

Read and write init paths are almost identical.  Unify them into
idetape_init_rw().

Signed-off-by: Tejun Heo <tj@kernel.org>
2009-04-19 08:46:02 +09:00
Tejun Heo
963da55c4b ide-tape: kill idetape_bh
Impact: kill now unnecessary idetape_bh

With everything using standard mechanisms, there is no need for
idetape_bh anymore.  Kill it and use tape->buf, cur and valid to
describe data buffer instead.

Changes worth mentioning are...

* idetape_queue_rq_tail() now always queue tape->buf and and adjusts
  buffer state properly before completion.

* idetape_pad_zeros() clears the buffer only once.

Signed-off-by: Tejun Heo <tj@kernel.org>
2009-04-19 08:46:02 +09:00
Tejun Heo
21d9c5d227 ide-tape: use standard data transfer mechanism
Impact: use standard way to transfer data

ide-tape uses rq in an interesting way.  For r/w requests, rq->special
is used to carry a private buffer management structure idetape_bh and
rq->nr_sectors and current_nr_sectors are initialized to the number of
idetape blocks which isn't necessary 512 bytes.  Also,
rq->current_nr_sectors is used to report back the residual count in
units of idetape blocks.

This peculiarity taxes both block layer and ide.  ide-atapi has
different paths and hooks to accomodate it and what a rq means becomes
quite confusing and making changes at the block layer becomes quite
difficult and error-prone.

This patch makes ide-tape use bio instead.  With the previous patch,
ide-tape currently is using single contiguos buffer so replacing it
isn't difficult.  Data buffer is mapped into bio using
blk_rq_map_kern() in idetape_queue_rw_tail().  idetape_io_buffers()
and idetape_update_buffers() are dropped and pc->bh is set to null to
tell ide-atapi to use standard data transfer mechanism and idetape_bh
byte counts are updated by the issuer on completion using the residual
count.

This change also nicely removes the FIXME in ide_pc_intr() where
ide-tape rqs need to be completed using ide_rq_bytes() instead of
blk_rq_bytes() (although this didn't really matter as the request
didn't have bio).

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <jens.axboe@oracle.com>
2009-04-19 08:46:02 +09:00
Tejun Heo
35ab8d3251 ide-tape: use single continuous buffer
Impact: simpler buffer allocation and handling, kills OOM, fix DMA transfers

ide-tape has its own multiple buffer mechanism using struct
idetape_bh.  It allocates buffer with decreasing order-of-two
allocations so that it results in minimum number of segments.
However, the implementation is quite complex and works in a way that
no other block or ide driver works necessitating a lot of special case
handling.

The benefit this complex allocation scheme brings is questionable as
PIO or DMA the number of segments (16 maximum) doesn't make any
noticeable difference and it also doesn't negate the need for multiple
order allocation which can fail under memory pressure or high
fragmentation although it does lower the highest order necessary by
one when the buffer size isn't power of two.

As the first step to remove the custom buffer management, this patch
makes ide-tape allocate single continous buffer.  The maximum order is
four.  I doubt the change would cause any trouble but if it ever
matters, it should be converted to regular sg mechanism like everyone
else and even in that case dropping custom buffer handling and moving
to standard mechanism first make sense as an intermediate step.

This patch makes the first bh to contain the whole buffer and drops
multi bh handling code.  Following patches will make further changes.

This patch has the side effect of killing OOM triggered by allocation
path and fixing DMA transfers.  Previously, bug in alloc path
triggered OOM on command issue and commands were passed to DMA engine
without DMA-mapping all the segments.

Signed-off-by: Tejun Heo <tj@kernel.org>
2009-04-19 08:46:02 +09:00
Tejun Heo
b3071d190d ide-atapi,tape,floppy: allow ->pc_callback() to change rq->data_len
Impact: allow residual count implementation in ->pc_callback()

rq->data_len has two duties - carrying the number of input bytes on
issue and carrying residual count back to the issuer on completion.
ide-atapi completion callback ->pc_callback() is the right place to do
this but currently ide-atapi depends on rq->data_len carrying the
original request size after calling ->pc_callback() to complete the pc
request.

This patch makes ide_pc_intr(), ide_tape_issue_pc() and
ide_floppy_issue_pc() cache length to complete before calling
->pc_callback() so that it can modify rq->data_len as necessary.

Note: As using rq->data_len for two purposes can make cases like this
      incorrect in subtle ways, future changes will introduce separate
      field for residual count.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <jens.axboe@oracle.com>
2009-04-19 08:46:02 +09:00