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path: root/drivers/ide/ide-tape.c
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2009-09-22const: make block_device_operations constAlexey Dobriyan
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>
2009-09-01ide: convert to ->proc_fopsAlexey Dobriyan
->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>
2009-08-07ide-tape: fix handling of postponed rqsBorislav Petkov
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>
2009-08-07ide-tape: convert to ide_debug_log macroBorislav Petkov
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>
2009-08-07ide-tape: fix debug callMark de Wever
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>
2009-07-21ide-tape: Don't leak kernel stack informationMichael Buesch
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>
2009-06-15ide: BUG() on unknown requestsBartlomiej Zolnierkiewicz
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>
2009-06-15ide-tape: fix build issueBorislav Petkov
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>
2009-06-13Merge branch 'bp-remove-pc-buf' into for-nextBartlomiej Zolnierkiewicz
Conflicts: drivers/ide/ide-tape.c
2009-06-12Merge branch 'for-2.6.31' of ↵Linus Torvalds
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) ...
2009-06-11Merge branch 'for-2.6.31' of git://git.kernel.dk/linux-2.6-blockLinus Torvalds
* '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
2009-06-08ide-tape: fix proc warningBorislav Petkov
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>
2009-06-07ide-tape: fix IDE_AFLAG_* atomic accessesBorislav Petkov
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>
2009-06-07ide-tape: change IDE_AFLAG_IGNORE_DSC non-atomicallyBorislav Petkov
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>
2009-05-19block: set rq->resid_len to blk_rq_bytes() on issueTejun Heo
In commit c3a4d78c580de4edc9ef0f7c59812fb02ceb037f, 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>
2009-05-17ide-tape: fix debug callMark de Wever
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>
2009-05-15ide-atapi: remove pc->bufBorislav Petkov
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>
2009-05-15ide-tape: fix READ POSITION cmd handlingBorislav Petkov
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>
2009-05-15ide-tape/ide_tape_get_bsize_from_bdesc: use local bufferBorislav Petkov
There should be no functional change resulting from this patch. Signed-off-by: Borislav Petkov <petkovbb@gmail.com>
2009-05-15ide-atapi: use local sense bufferBorislav Petkov
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>
2009-05-15ide-atapi: add a buffer-arg to ide_queue_pc_tailBorislav Petkov
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>
2009-05-15ide-atapi: add a len-parameter to ide_queue_pc_tailBorislav Petkov
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>
2009-05-15ide-atapi: switch to rq->resid_lenBorislav Petkov
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>
2009-05-15ide-atapi: switch to blk_rq_bytes() on do_request() pathBorislav Petkov
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>
2009-05-15ide-tape: fix potential fs requests bugBorislav Petkov
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>
2009-05-11ide: cleanup rq->data_len usagesTejun Heo
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>
2009-05-11ide: convert to rq pos and nr_sectors accessorsTejun Heo
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>
2009-05-11block: add rq->resid_lenTejun Heo
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>
2009-05-11ide-tape: don't initialize rq->sector for rw requestsTejun Heo
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>
2009-04-28ide-atapi: kill unused fields and callbacksTejun Heo
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>
2009-04-28ide-tape: simplify read/write functionsTejun Heo
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>
2009-04-28ide-tape: use byte size instead of sectors on rw issue functionsTejun Heo
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>
2009-04-28ide-tape: unify r/w init pathsTejun Heo
Impact: cleanup Read and write init paths are almost identical. Unify them into idetape_init_rw(). Signed-off-by: Tejun Heo <tj@kernel.org>
2009-04-28ide-tape: kill idetape_bhTejun Heo
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>
2009-04-28ide-tape: use standard data transfer mechanismTejun Heo
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>
2009-04-28ide-tape: use single continuous bufferTejun Heo
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>
2009-04-28ide-atapi,tape,floppy: allow ->pc_callback() to change rq->data_lenTejun Heo
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>
2009-04-28ide-tape,floppy: fix failed command completion after request senseTejun Heo
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>
2009-04-28ide-cd,atapi: use bio for internal commandsTejun Heo
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>
2009-04-28ide-atapi: convert ide-{floppy,tape} to using preallocated sense bufferBorislav Petkov
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>
2009-04-28ide-atapi: don't abuse rq->bufferTejun Heo
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>
2009-04-28ide-tape: remove back-to-back REQUEST_SENSE detectionTejun Heo
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>
2009-04-19ide-atapi: kill unused fields and callbacksTejun Heo
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>
2009-04-19ide-tape: simplify read/write functionsTejun Heo
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>
2009-04-19ide-tape: use byte size instead of sectors on rw issue functionsTejun Heo
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>
2009-04-19ide-tape: unify r/w init pathsTejun Heo
Impact: cleanup Read and write init paths are almost identical. Unify them into idetape_init_rw(). Signed-off-by: Tejun Heo <tj@kernel.org>
2009-04-19ide-tape: kill idetape_bhTejun Heo
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>
2009-04-19ide-tape: use standard data transfer mechanismTejun Heo
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>
2009-04-19ide-tape: use single continuous bufferTejun Heo
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>
2009-04-19ide-atapi,tape,floppy: allow ->pc_callback() to change rq->data_lenTejun Heo
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>