02 Aug, 2010

1 commit

  • Make the following changes to prepare for NCQ command completion
    update. Changes made by this patch don't cause any functional
    difference.

    * sata_fsl_host_intr(): rename the local variable qc_active to
    done_mask as that's what it is.

    * mv_process_crpb_response(): restructure if clause for easier update.

    * nv_adma_interrupt(): drop unnecessary error variable.

    * nv_swncq_sdbfis(): drop unnecessary nr_done and return 0 on success.
    Typo fix.

    * nv_swncq_dmafis(): drop unused return value and return void.

    * nv_swncq_host_interrupt(): drop unnecessary return value handling.

    Signed-off-by: Tejun Heo
    Cc: Ashish Kalra
    Cc: Saeed Bishara
    Cc: Mark Lord
    Cc: Robert Hancock
    Signed-off-by: Jeff Garzik

    Tejun Heo
     

03 Jun, 2010

1 commit

  • On mcp55, nIEN gets stuck once set and liteon blueray rom iHOS104-08
    violates ATA specification and fails to set I on D2H Reg FIS if nIEN
    is set when the command was issued. When the other party is following
    the spec, both devices can work fine but when the two flaws are put
    together, they can't talk to each other.

    mcp55 has its own IRQ masking mechanism and there's no reason to mess
    with nIEN in the first place. Fix it by dropping nIEN diddling from
    nv_mcp55_freeze/thaw().

    This was originally reported by Cengiz. Although Cengiz hasn't
    verified the fix yet, I could reproduce this problem and verfiy the
    fix. Even if Cengiz is experiencing different or additional problems,
    this patch is needed.

    Signed-off-by: Tejun Heo
    Reported-by: Cengiz Günay
    Cc: stable@kernel.org
    Signed-off-by: Jeff Garzik

    Tejun Heo
     

26 May, 2010

3 commits

  • Separate out ata_pci_bmdma_prepare_host() and ata_pci_bmdma_init_one()
    from their SFF counterparts. SFF ones no longer try to initialize
    BMDMA or set PCI master.

    Signed-off-by: Tejun Heo
    Signed-off-by: Jeff Garzik

    Tejun Heo
     
  • Separate out BMDMA irq handler from SFF irq handler. The misnamed
    host_intr() functions are renamed to ata_sff_port_intr() and
    ata_bmdma_port_intr(). Common parts are factored into
    __ata_sff_port_intr() and __ata_sff_interrupt() and used by sff and
    bmdma interrupt routines.

    All BMDMA drivers now use ata_bmdma_interrupt() or
    ata_bmdma_port_intr() while all non-BMDMA SFF ones use
    ata_sff_interrupt() or ata_sff_port_intr().

    For now, ata_pci_sff_init_one() uses ata_bmdma_interrupt() as it's
    used by both SFF and BMDMA drivers.

    Signed-off-by: Tejun Heo
    Signed-off-by: Jeff Garzik

    Tejun Heo
     
  • ata_sff_irq_clear() is BMDMA specific. Rename it to
    ata_bmdma_irq_clear(), move it to ata_bmdma_port_ops and make
    ->sff_irq_clear() optional.

    Note: ata_bmdma_irq_clear() is actually only needed by ata_piix and
    possibly by sata_sil. This should be moved to respective low
    level drivers later.

    Signed-off-by: Tejun Heo
    Signed-off-by: Jeff Garzik

    Tejun Heo
     

20 May, 2010

5 commits

  • Separate out ata_bmdma_qc_issue() from ata_sff_qc_issue() such that
    ata_sff_qc_issue() only deals with non-BMDMA SFF protocols (PIO and
    nodata) while ata_bmdma_qc_issue() deals with the BMDMA protocols and
    uses ata_sff_qc_issue() for non-DMA commands. All the users are
    updated accordingly.

    Signed-off-by: Tejun Heo
    Signed-off-by: Jeff Garzik

    Tejun Heo
     
  • struct ata_prd and ap->prd are BMDMA specific. Add bmdma_ prefix to
    them and move them inside CONFIG_ATA_SFF.

    Signed-off-by: Tejun Heo
    Signed-off-by: Jeff Garzik

    Tejun Heo
     
  • Both qc_prep functions deal only with BMDMA PRD setup and PIO only SFF
    drivers don't need them. Rename to ata_bmdma_[dumb_]qc_prep() and
    relocate.

    All usages are renamed except for pdc_adma and sata_qstor. Those two
    drivers are not BMDMA drivers and don't need to call BMDMA qc_prep
    functions. Calls to ata_sff_qc_prep() in the two drivers are removed.

    Signed-off-by: Tejun Heo
    Signed-off-by: Jeff Garzik

    Tejun Heo
     
  • Some of error handling logic in ata_sff_error_handler() and all of
    ata_sff_post_internal_cmd() are for BMDMA. Create
    ata_bmdma_error_handler() and ata_bmdma_post_internal_cmd() and move
    BMDMA part into those.

    While at it, change DMA protocol check to ata_is_dma(), fix
    post_internal_cmd to call ap->ops->bmdma_stop instead of directly
    calling ata_bmdma_stop() and open code hardreset selection so that
    ata_std_error_handler() doesn't have to know about sff hardreset.

    As these two functions are BMDMA specific, there's no reason to check
    for bmdma_addr before calling bmdma methods if the protocol of the
    failed command is DMA. sata_mv and pata_mpc52xx now don't need to set
    .post_internal_cmd to ATA_OP_NULL and pata_icside and sata_qstor don't
    need to set it to their bmdma_stop routines.

    ata_sff_post_internal_cmd() becomes noop and is removed.

    This fixes p3 described in clean-up-BMDMA-initialization patch.

    Signed-off-by: Tejun Heo
    Signed-off-by: Jeff Garzik

    Tejun Heo
     
  • When BMDMA initialization failed or BMDMA was not available for
    whatever reason, bmdma_addr was left at zero and used as an indication
    that BMDMA shouldn't be used. This leads to the following problems.

    p1. For BMDMA drivers which don't use traditional BMDMA register,
    ata_bmdma_mode_filter() incorrectly inhibits DMA modes. Those
    drivers either have to inherit from ata_sff_port_ops or clear
    ->mode_filter explicitly.

    p2. non-BMDMA drivers call into BMDMA PRD table allocation. It
    doesn't actually allocate PRD table if bmdma_addr is not
    initialized but is still confusing.

    p3. For BMDMA drivers which don't use traditional BMDMA register, some
    methods might not be invoked as expected (e.g. bmdma_stop from
    ata_sff_post_internal_cmd()).

    p4. SFF drivers w/ custom DMA interface implement noop BMDMA ops
    worrying libata core might call into one of them.

    These problems are caused by the muddy line between SFF and BMDMA and
    the assumption that all BMDMA controllers initialize bmdma_addr.

    This patch fixes p1 and p2 by removing the bmdma_addr assumption and
    moving prd allocation to BMDMA port start. Later patches will fix the
    remaining issues.

    This patch improves BMDMA initialization such that

    * When BMDMA register initialization fails, falls back to PIO instead
    of failing. ata_pci_bmdma_init() never fails now.

    * When ata_pci_bmdma_init() falls back to PIO, it clears
    ap->mwdma_mask and udma_mask instead of depending on
    ata_bmdma_mode_filter(). This makes ata_bmdma_mode_filter()
    unnecessary thus resolving p1.

    * ata_port_start() which actually is BMDMA specific is moved to
    ata_bmdma_port_start(). ata_port_start() and ata_sff_port_start()
    are killed.

    * ata_sff_port_start32() is moved and renamed to
    ata_bmdma_port_start32().

    Drivers which no longer call into PRD table allocation are...

    pdc_adma, sata_inic162x, sata_qstor, sata_sx4, pata_cmd640 and all
    drivers which inherit from ata_sff_port_ops.

    pata_icside sets ->port_start to ATA_OP_NULL as it doesn't need PRD
    but is a BMDMA controller and doesn't have custom port_start like
    other such controllers.

    Note that with the previous patch which makes all and only BMDMA
    drivers inherit from ata_bmdma_port_ops, this change doesn't break
    drivers which need PRD table.

    Signed-off-by: Tejun Heo
    Signed-off-by: Jeff Garzik

    Tejun Heo
     

18 May, 2010

1 commit

  • ATA_FLAG_DISABLED is only used by drivers which don't use
    ->error_handler framework and is largely broken. Its only meaningful
    function is to make irq handlers skip processing if the flag is set,
    which is largely useless and even harmful as it makes those ports more
    likely to cause IRQ storms.

    Kill ATA_FLAG_DISABLED and makes the callers disable attached devices
    instead. ata_port_probe() and ata_port_disable() which manipulate the
    flag are also killed.

    This simplifies condition check in IRQ handlers. While updating IRQ
    handlers, remove ap NULL check as libata guarantees consecutive port
    allocation (unoccupied ports are initialized with dummies) and
    long-obsolete ATA_QCFLAG_ACTIVE check (checked by ata_qc_from_tag()).

    Signed-off-by: Tejun Heo
    Signed-off-by: Jeff Garzik

    Tejun Heo
     

15 May, 2010

1 commit


30 Mar, 2010

1 commit

  • …it slab.h inclusion from percpu.h

    percpu.h is included by sched.h and module.h and thus ends up being
    included when building most .c files. percpu.h includes slab.h which
    in turn includes gfp.h making everything defined by the two files
    universally available and complicating inclusion dependencies.

    percpu.h -> slab.h dependency is about to be removed. Prepare for
    this change by updating users of gfp and slab facilities include those
    headers directly instead of assuming availability. As this conversion
    needs to touch large number of source files, the following script is
    used as the basis of conversion.

    http://userweb.kernel.org/~tj/misc/slabh-sweep.py

    The script does the followings.

    * Scan files for gfp and slab usages and update includes such that
    only the necessary includes are there. ie. if only gfp is used,
    gfp.h, if slab is used, slab.h.

    * When the script inserts a new include, it looks at the include
    blocks and try to put the new include such that its order conforms
    to its surrounding. It's put in the include block which contains
    core kernel includes, in the same order that the rest are ordered -
    alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
    doesn't seem to be any matching order.

    * If the script can't find a place to put a new include (mostly
    because the file doesn't have fitting include block), it prints out
    an error message indicating which .h file needs to be added to the
    file.

    The conversion was done in the following steps.

    1. The initial automatic conversion of all .c files updated slightly
    over 4000 files, deleting around 700 includes and adding ~480 gfp.h
    and ~3000 slab.h inclusions. The script emitted errors for ~400
    files.

    2. Each error was manually checked. Some didn't need the inclusion,
    some needed manual addition while adding it to implementation .h or
    embedding .c file was more appropriate for others. This step added
    inclusions to around 150 files.

    3. The script was run again and the output was compared to the edits
    from #2 to make sure no file was left behind.

    4. Several build tests were done and a couple of problems were fixed.
    e.g. lib/decompress_*.c used malloc/free() wrappers around slab
    APIs requiring slab.h to be added manually.

    5. The script was run on all .h files but without automatically
    editing them as sprinkling gfp.h and slab.h inclusions around .h
    files could easily lead to inclusion dependency hell. Most gfp.h
    inclusion directives were ignored as stuff from gfp.h was usually
    wildly available and often used in preprocessor macros. Each
    slab.h inclusion directive was examined and added manually as
    necessary.

    6. percpu.h was updated not to include slab.h.

    7. Build test were done on the following configurations and failures
    were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
    distributed build env didn't work with gcov compiles) and a few
    more options had to be turned off depending on archs to make things
    build (like ipr on powerpc/64 which failed due to missing writeq).

    * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
    * powerpc and powerpc64 SMP allmodconfig
    * sparc and sparc64 SMP allmodconfig
    * ia64 SMP allmodconfig
    * s390 SMP allmodconfig
    * alpha SMP allmodconfig
    * um on x86_64 SMP allmodconfig

    8. percpu.h modifications were reverted so that it could be applied as
    a separate patch and serve as bisection point.

    Given the fact that I had only a couple of failures from tests on step
    6, I'm fairly confident about the coverage of this conversion patch.
    If there is a breakage, it's likely to be something in one of the arch
    headers which should be easily discoverable easily on most builds of
    the specific arch.

    Signed-off-by: Tejun Heo <tj@kernel.org>
    Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
    Cc: Ingo Molnar <mingo@redhat.com>
    Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

    Tejun Heo
     

26 Feb, 2010

1 commit


05 Dec, 2009

1 commit

  • This patch modifies scsi_host_template->change_queue_depth so that
    it takes an argument indicating why it is being called. This will be
    used so that if a LLD needs to do some extra processing when
    handling queue fulls or later ramp ups, it can do so.

    This is a simple port of the drivers setting a change_queue_depth
    callback. In the patch I just have these LLDs adjust the queue depth
    if the user was requesting it.

    Signed-off-by: Mike Christie

    [Vasu.Dev: v2
    Also converted pmcraid_change_queue_depth and then verified
    all modules compile using "make allmodconfig" for any new build
    warnings on X86_64.

    Updated original description after combing two original
    patches from Mike to make this patch git bisectable.]
    Signed-off-by: Vasu Dev
    [jejb: fixed up 53c700]
    Signed-off-by: James Bottomley

    Mike Christie
     

16 Oct, 2009

1 commit

  • prereset doesn't bring link online if hardreset is about to happen and
    nv_hardreset() may skip if conditions are not right so softreset may
    be entered with non-working link status if the system firmware didn't
    bring it up before entering OS code which can happen during resume.
    This patch makes nv_hardreset() to bring up the link if it's skipping
    reset.

    This bug was reported by frodone@gmail.com in the following bug entry.

    http://bugzilla.kernel.org/show_bug.cgi?id=14329

    Signed-off-by: Tejun Heo
    Reported-by: frodone@gmail.com
    Cc: stable@kernel.org
    Signed-off-by: Jeff Garzik

    Tejun Heo
     

12 Aug, 2009

1 commit

  • At least the nVidia MCP55 controller quite happily supports MSI.
    This adds an option to use it. It is disabled by default.
    As per feedback by Robert Hancock, it will honour the user
    request as the kernel will not enable MSI where the controller
    or the specific system configuration do not support it.

    Signed-off-by: Tony Vroon
    Cc: Robert Hancock
    Signed-off-by: Jeff Garzik

    Tony Vroon
     

10 Jun, 2009

1 commit

  • When I thought it was finally defeated, it came back with vengeance.
    The failure cases are ever more convoluted. Now there is a single
    combination which fails boot probing - MCP5x + Intel SSD and there are
    two hotplug failure reports on different flavors where softreset fails
    to bring up the device.

    Through the many bug reports after the switch to hardreset, the
    following patterns emerged.

    - Softreset during boot always works.

    - Hardreset during boot sometimes fails to bring up the link on
    certain comibnations and device signature acquisition is unreliable.

    - Hardreset is often necessary after hotplug.

    It looks like the old behavior of preferring softreset was somehow
    pretty close to the working reset protocol although it could have lost
    a device during phy error handling by issuing hardreset.

    This patch implements nv_hardreset() which kicks in only for post-boot
    (!LOADING) device probing resets. This should be able to work around
    all known problem cases. This isn't perfect but given the various
    hardreset quirks on these controllers, I think this is as good as it
    can get.

    Tested on mcp5x (swncq), nf3 and ck804 for all both boot, warm and
    hot probing cases.

    Kudos to all the bug reporters and their painful hours with these damn
    controllers. ;-)

    Signed-off-by: Tejun Heo
    Cc: Robert Hancock
    Reported-by: David Lang
    Reported-by: Samo Vodopivec
    Signed-off-by: Jeff Garzik

    Tejun Heo
     

25 Mar, 2009

2 commits


05 Mar, 2009

1 commit


17 Feb, 2009

1 commit


03 Feb, 2009

1 commit

  • While playing with nvraid, I found out that rmmoding and insmoding
    often trigger hardreset failure on the first port (the second one was
    always okay). Seriously, how diverse can you get with hardreset
    behaviors? Anyways, make ck804 use noclassify variant too.

    Signed-off-by: Tejun Heo
    Signed-off-by: Jeff Garzik

    Tejun Heo
     

26 Jan, 2009

2 commits

  • MCP5x family of controllers seem to share much more with nf2's as far
    as reset protocol is concerned. It requires heardreset to get the PHY
    going and classfication code report after hardreset is unreliable.
    Create a new board type MCP5x and use noclassify hardreset. SWNCQ is
    modified to inherit from this new type.

    This fixes hotplug regression reported in kernel bz#12351.

    Signed-off-by: Tejun Heo
    Signed-off-by: Jeff Garzik

    Tejun Heo
     
  • nv_nf2_hardreset() will be used by other flavors too. Rename it to
    nv_noclassify_hardreset().

    Signed-off-by: Tejun Heo
    Signed-off-by: Jeff Garzik

    Tejun Heo
     

04 Nov, 2008

1 commit

  • All three flavors of sata_nv's are different in how their hardreset
    behaves.

    * generic: Hardreset is not reliable. Link often doesn't come online
    after hardreset.

    * nf2/3: A little bit better - link comes online with longer debounce
    timing. However, nf2/3 can't reliable wait for the first D2H
    Register FIS, so it can't wait for device readiness or classify the
    device after hardreset. Follow-up SRST required.

    * ck804: Hardreset finally works.

    The core layer change to prefer hardreset and follow up changes
    exposed the above issues and caused various detection regressions for
    all three flavors. This patch, hopefully, fixes all the known issues
    and should make sata_nv error handling more reliable.

    Signed-off-by: Tejun Heo
    Signed-off-by: Jeff Garzik

    Tejun Heo
     

10 Oct, 2008

1 commit

  • * 'upstream-2.6.28' of git://git.kernel.org/pub/scm/linux/kernel/git/jgarzik/libata-dev:
    ata_piix: IDE Mode SATA patch for Intel Ibex Peak DeviceIDs
    libata-eh: clear UNIT ATTENTION after reset
    ata_piix: add Hercules EC-900 mini-notebook to ich_laptop short cable list
    libata: reorder ata_device to remove 8 bytes of padding on 64 bits
    [libata] pata_bf54x: Add proper PM operation
    pata_sil680: convert CONFIG_PPC_MERGE to CONFIG_PPC
    libata: Implement disk shock protection support
    [libata] Introduce ata_id_has_unload()
    PATA: RPC now selects HAVE_PATA_PLATFORM for pata platform driver
    ata_piix: drop merged SCR access and use slave_link instead
    libata: implement slave_link
    libata: misc updates to prepare for slave link
    libata: reimplement link iterator
    libata: make SCR access ops per-link

    Linus Torvalds
     

29 Sep, 2008

2 commits

  • Logically, SCR access ops should take @link; however, there was no
    compelling reason to convert all SCR access ops when adding @link
    abstraction as there's one-to-one mapping between a port and a non-PMP
    link. However, that assumption won't hold anymore with the scheduled
    addition of slave link.

    Make SCR access ops per-link.

    Signed-off-by: Tejun Heo
    Signed-off-by: Jeff Garzik

    Tejun Heo
     
  • Commit 2fd673ecf0378ddeeeb87b3605e50212e0c0ddc6 which tried to remove
    hardreset for generic accidentally removed it for all flavors as all
    others were inheriting from nv_generic_ops. This patch reinstates
    nv_hardreset() and puts it into nv_common_ops which all flavors
    inherit from. nv_generic_ops now inherits from nv_common_ops and
    overrides .hardreset to ATA_OP_NULL.

    While at it, explain why nv_hardreset and ATA_OP_NULL override are
    necessary.

    Signed-off-by: Tejun Heo
    Signed-off-by: Jeff Garzik

    Tejun Heo
     

09 Sep, 2008

1 commit

  • of them being unifying probing, hotplug and EH reset paths uniform.
    Previously, broken hardreset could go unnoticed as it wasn't used
    during probing but when something goes wrong or after hotplug the
    problem will surface and bite hard.

    OSDL bug 11195 reports that sata_nv generic flavor falls into this
    category. Hardreset itself succeeds but PHY stays offline after
    hardreset. I tried longer debounce timing but the result was the
    same.

    http://bugzilla.kernel.org/show_bug.cgi?id=11195

    So, it seems we'll have to drop hardreset from the generic flavor.

    Signed-off-by: Tejun Heo
    Cc: Peer Chen
    Signed-off-by: Jeff Garzik

    Tejun Heo
     

25 Apr, 2008

1 commit

  • sata_nv hardreset can't classify but was left out while unifying
    follow-up SRST request mechanism[1]. This caused detection failures
    on those controllers. Fix it.

    Reported and bisected by Roland Dreier, Petr Vandrovec and Marc
    Dionne. Thanks guys.

    [1] 305d2a1ab137d11d573319c315748a87060fe82d

    Signed-off-by: Tejun Heo
    Cc: Roland Dreier
    Cc: Petr Vandrovec
    Cc: Marc Dionne
    Signed-off-by: Jeff Garzik

    Tejun Heo
     

18 Apr, 2008

9 commits

  • Add sff_ prefix to SFF specific port ops.

    This rename is in preparation of separating SFF support out of libata
    core layer. This patch strictly renames ops and doesn't introduce any
    behavior difference.

    Signed-off-by: Tejun Heo

    Tejun Heo
     
  • SFF functions have confusing names. Some have sff prefix, some have
    bmdma, some std, some pci and some none. Unify the naming by...

    * SFF functions which are common to both BMDMA and non-BMDMA are
    prefixed with ata_sff_.

    * SFF functions which are specific to BMDMA are prefixed with
    ata_bmdma_.

    * SFF functions which are specific to PCI but apply to both BMDMA and
    non-BMDMA are prefixed with ata_pci_sff_.

    * SFF functions which are specific to PCI and BMDMA are prefixed with
    ata_pci_bmdma_.

    * Drop generic prefixes from LLD specific routines. For example,
    bfin_std_dev_select -> bfin_dev_select.

    The following renames are noteworthy.

    ata_qc_issue_prot() -> ata_sff_qc_issue()
    ata_pci_default_filter() -> ata_bmdma_mode_filter()
    ata_dev_try_classify() -> ata_sff_dev_classify()

    This rename is in preparation of separating SFF support out of libata
    core layer. This patch strictly renames functions and doesn't
    introduce any behavior difference.

    Signed-off-by: Tejun Heo

    Tejun Heo
     
  • Continues to have open issues, and engineering support is extremely difficult
    to come by, according to fellow NVIDIA engineers.

    Signed-off-by: Jeff Garzik

    Jeff Garzik
     
  • Signed-off-by: Zoltan Boszormenyi
    Cc: Robert Hancock
    Signed-off-by: Andrew Morton
    Signed-off-by: Jeff Garzik

    Zoltan Boszormenyi
     
  • Currently reset methods are not specified directly in the
    ata_port_operations table. If a LLD wants to use custom reset
    methods, it should construct and use a error_handler which uses those
    reset methods. It's done this way for two reasons.

    First, the ops table already contained too many methods and adding
    four more of them would noticeably increase the amount of necessary
    boilerplate code all over low level drivers.

    Second, as ->error_handler uses those reset methods, it can get
    confusing. ie. By overriding ->error_handler, those reset ops can be
    made useless making layering a bit hazy.

    Now that ops table uses inheritance, the first problem doesn't exist
    anymore. The second isn't completely solved but is relieved by
    providing default values - most drivers can just override what it has
    implemented and don't have to concern itself about higher level
    callbacks. In fact, there currently is no driver which actually
    modifies error handling behavior. Drivers which override
    ->error_handler just wraps the standard error handler only to prepare
    the controller for EH. I don't think making ops layering strict has
    any noticeable benefit.

    This patch makes ->prereset, ->softreset, ->hardreset, ->postreset and
    their PMP counterparts propoer ops. Default ops are provided in the
    base ops tables and drivers are converted to override individual reset
    methods instead of creating custom error_handler.

    * ata_std_error_handler() doesn't use sata_std_hardreset() if SCRs
    aren't accessible. sata_promise doesn't need to use separate
    error_handlers for PATA and SATA anymore.

    * softreset is broken for sata_inic162x and sata_sx4. As libata now
    always prefers hardreset, this doesn't really matter but the ops are
    forced to NULL using ATA_OP_NULL for documentation purpose.

    * pata_hpt374 needs to use different prereset for the first and second
    PCI functions. This used to be done by branching from
    hpt374_error_handler(). The proper way to do this is to use
    separate ops and port_info tables for each function. Converted.

    Signed-off-by: Tejun Heo

    Tejun Heo
     
  • libata core layer doesn't care about sht or ->irq_handler. Those are
    only of interest to the LLD during initialization. This is confusing
    and has caused several drivers to have duplicate unused initializers
    for these fields.

    Currently only sata_nv uses these fields. Make sata_nv use
    ->private_data, which is supposed to carry LLD-specific information,
    instead and kill ->sht and ->irq_handler. nv_pi_priv structure is
    defined and struct literals are used to initialize private_data.
    Notational overhead is negligible.

    Signed-off-by: Tejun Heo

    Tejun Heo
     
  • libata lets low level drivers build ata_port_operations table and
    register it with libata core layer. This allows low level drivers
    high level of flexibility but also burdens them with lots of
    boilerplate entries.

    This becomes worse for drivers which support related similar
    controllers which differ slightly. They share most of the operations
    except for a few. However, the driver still needs to list all
    operations for each variant. This results in large number of
    duplicate entries, which is not only inefficient but also error-prone
    as it becomes very difficult to tell what the actual differences are.

    This duplicate boilerplates all over the low level drivers also make
    updating the core layer exteremely difficult and error-prone. When
    compounded with multi-branched development model, it ends up
    accumulating inconsistencies over time. Some of those inconsistencies
    cause immediate problems and fixed. Others just remain there dormant
    making maintenance increasingly difficult.

    To rectify the problem, this patch implements ata_port_operations
    inheritance. To allow LLDs to easily re-use their own ops tables
    overriding only specific methods, this patch implements poor man's
    class inheritance. An ops table has ->inherits field which can be set
    to any ops table as long as it doesn't create a loop. When the host
    is started, the inheritance chain is followed and any operation which
    isn't specified is taken from the nearest ancestor which has it
    specified. This operation is called finalization and done only once
    per an ops table and the LLD doesn't have to do anything special about
    it other than making the ops table non-const such that libata can
    update it.

    libata provides four base ops tables lower drivers can inherit from -
    base, sata, pmp, sff and bmdma. To avoid overriding these ops
    accidentaly, these ops are declared const and LLDs should always
    inherit these instead of using them directly.

    After finalization, all the ops table are identical before and after
    the patch except for setting .irq_handler to ata_interrupt in drivers
    which didn't use to. The .irq_handler doesn't have any actual effect
    and the field will soon be removed by later patch.

    * sata_sx4 is still using old style EH and currently doesn't take
    advantage of ops inheritance.

    Signed-off-by: Tejun Heo

    Tejun Heo
     
  • libata lets low level drivers build scsi_host_template and register it
    to the SCSI layer. This allows low level drivers high level of
    flexibility but also burdens them with lots of boilerplate entries.

    This patch implements SHT initializers which can be used to initialize
    all the boilerplate entries in a sht. Three variants of them are
    implemented - BASE, BMDMA and NCQ - for different types of drivers.
    Note that entries can be overriden by putting individual initializers
    after the helper macro.

    All sht tables are identical before and after this patch.

    Signed-off-by: Tejun Heo

    Tejun Heo
     
  • Over the time, port info, ops and sht structures developed quite a bit
    of inconsistencies. This patch updates drivers.

    * Enable/disable_pm callbacks added to all ahci ops tables.

    * Every driver for SFF controllers now uses ata_sff_port_start()
    instead of ata_port_start() unless the driver has custom
    implementation.

    * Every driver for SFF controllers now uses ata_pci_default_filter()
    unless the driver has custom implementation.

    * Removed an odd port_info->sht initialization from ata_piix.c.
    Likely a merge byproduct.

    * A port which has ATA_FLAG_SATA set doesn't need to set cable_detect
    to ata_cable_sata(). Remove it from via and mv port ops.

    * Some drivers had unnecessary .max_sectors initialization which is
    ignored and was missing .slave_destroy callback. Fixed.

    * Removed unnecessary sht initializations port_info's.

    * Removed onsolete scsi device suspend/resume callbacks from
    pata_bf54x.

    * No reason to set ata_pci_default_filter() and bmdma functions for
    PIO-only drivers. Remove those callbacks and replace
    ata_bmdma_irq_clear with ata_noop_irq_clear.

    * pata_platform sets port_start to ata_dummy_ret0. port_start can
    just be set to NULL.

    * sata_fsl supports NCQ but was missing qc_defer. Fixed.

    * pata_rb600_cf implements dummy port_start. Removed.

    Signed-off-by: Tejun Heo

    Tejun Heo