24 Jul, 2011

1 commit

  • Saves text by removing nearly duplicated text format strings by
    creating ata__printk functions and printf extension %pV.

    ata defconfig size shrinks ~5% (~8KB), allyesconfig ~2.5% (~13KB)

    Format string duplication comes from:

    #define ata_link_printk(link, lv, fmt, args...) do { \
    if (sata_pmp_attached((link)->ap) || (link)->ap->slave_link) \
    printk("%sata%u.%02u: "fmt, lv, (link)->ap->print_id, \
    (link)->pmp , ##args); \
    else \
    printk("%sata%u: "fmt, lv, (link)->ap->print_id , ##args); \
    } while(0)

    Coalesce long formats.

    $ size drivers/ata/built-in.*
    text data bss dec hex filename
    544969 73893 116584 735446 b38d6 drivers/ata/built-in.allyesconfig.ata.o
    558429 73893 117864 750186 b726a drivers/ata/built-in.allyesconfig.dev_level.o
    141328 14689 4220 160237 271ed drivers/ata/built-in.defconfig.ata.o
    149567 14689 4220 168476 2921c drivers/ata/built-in.defconfig.dev_level.o

    Signed-off-by: Joe Perches
    Signed-off-by: Jeff Garzik

    Joe Perches
     

26 May, 2010

1 commit

  • 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
     

20 May, 2010

3 commits

  • 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
     
  • 1. pata_cmd640 is PIO only. Inherit from sff.

    2. pata_macio is BMDMA. Inherit from bmdma and drop explicit
    bmdma_mode_filter() setting.

    3. In sata_mv, unlike mv5, mv6 is BMDMA. Inherit from bmdma and
    don't clear ->post_internal_cmd().

    4. bf54x and icside are quasi-BMDMA controllers which don't use the
    standard BMDMA registers so they don't initialize bmdma_addr and
    inherit from sff to avoid the default mode_filter which disables
    DMA modes if bmdma_addr is not initialized.

    For 2 and 3, this patch makes the drivers explicitly specify
    ->mode_filter to ATA_OP_NULL while inheriting from ata_bmdma_port_ops.
    These will be removed by the next patch.

    This patch makes all and only BMDMA drivers inherit from
    ata_bmdma_port_ops to ease further SFF/BMDMA separation.

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

    Tejun Heo
     

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
     

29 Mar, 2009

1 commit


25 Mar, 2009

1 commit


12 Dec, 2008

1 commit

  • The hardware supports transfers up to a page boundary per buffer.
    Currently, we work around that in the DMA code by splitting each
    buffer up as we run through the scatterlist. Avoid this by telling
    the block layers about the hardware restriction.

    Eventually, this will allow us to phase out the splitting code,
    but not until the old IDE layer allows us to control the value it
    gives to blk_queue_segment_boundary().

    Signed-off-by: Russell King

    Russell King
     

11 Dec, 2008

1 commit


04 Jun, 2008

1 commit

  • - Make ata_sff_altstatus private so nobody uses it by mistake
    - Drop the 400nS delay from it

    Add

    ata_sff_irq_status - encapsulates the IRQ check logic

    This function keeps the existing behaviour for altstatus using devices. I
    actually suspect the logic was wrong before the changes but -rc isn't the
    time to play with that

    ata_sff_sync - ensure writes hit the device

    Really we want an io* operation for 'is posted' eg ioisposted(ioaddr) so
    that we can fix the nasty delay this causes on most systems.

    - ata_sff_pause - 400nS delay

    Ensure the command hit the device and delay 400nS

    - ata_sff_dma_pause

    Ensure the I/O hit the device and enforce an HDMA1:0 transition delay.
    Requires altstatus register exists, BUG if not so we don't risk
    corruption in MWDMA modes. (UDMA the checksum will save your backside in
    theory)

    The only other complication then is devices with their own handlers.
    rb532 can use dma_pause but scc needs to access its own altstatus
    register for internal errata workarounds so directly call the drivers own
    altstatus function.

    Signed-off-by: Alan Cox
    Signed-off-by: Jeff Garzik

    Alan Cox
     

18 Apr, 2008

6 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
     
  • 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 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
     
  • ->irq_clear() is used to clear IRQ bit of a SFF controller and isn't
    useful for drivers which don't use libata SFF HSM implementation.
    However, it's a required callback and many drivers implement their own
    noop version as placeholder. This patch implements ata_noop_irq_clear
    and use it to replace those custom placeholders.

    Also, SFF drivers which don't support BMDMA don't need to use
    ata_bmdma_irq_clear(). It becomes noop if BMDMA address isn't
    initialized. Convert them to use ata_noop_irq_clear().

    Signed-off-by: Tejun Heo

    Tejun Heo
     

19 Feb, 2008

1 commit

  • that provided by the block layer

    ATA requires that all DMA transfers begin and end on word boundaries.
    Because of this, a large amount of machinery grew up in ide to adjust
    scatterlists on this basis. However, as of 2.5, the block layer has a
    dma_alignment variable which ensures both the beginning and length of a
    DMA transfer are aligned on the dma_alignment boundary. Although the
    block layer does adjust the beginning of the transfer to ensure this
    happens, it doesn't actually adjust the length, it merely makes sure
    that space is allocated for transfers beyond the declared length. The
    upshot of this is that scatterlists may be padded to any size between
    the actual length and the length adjusted to the dma_alignment safely
    knowing that memory is allocated in this region.

    Right at the moment, SCSI takes the default dma_aligment which is on a
    512 byte boundary. Note that this aligment only applies to transfers
    coming in from user space. However, since all kernel allocations are
    automatically aligned on a minimum of 32 byte boundaries, it is safe to
    adjust them in this manner as well.

    tj: * Adjusting sg after padding is done in block layer. Make libata
    set queue alignment correctly for ATAPI devices and drop broken
    sg mangling from ata_sg_setup().
    * Use request->raw_data_len for ATAPI transfer chunk size.
    * Killed qc->raw_nbytes.
    * Separated out killing qc->n_iter.

    Signed-off-by: James Bottomley
    Signed-off-by: Tejun Heo
    Signed-off-by: Jens Axboe

    James Bottomley
     

23 Jan, 2008

1 commit

  • libata used private sg iterator to handle padding sg. Now that sg can
    be chained, padding can be handled using standard sg ops. Convert to
    chained sg.

    * s/qc->__sg/qc->sg/

    * s/qc->pad_sgent/qc->extra_sg[]/. Because chaining consumes one sg
    entry. There need to be two extra sg entries. The renaming is also
    for future addition of other extra sg entries.

    * Padding setup is moved into ata_sg_setup_extra() which is organized
    in a way that future addition of other extra sg entries is easy.

    * qc->orig_n_elem is unused and removed.

    * qc->n_elem now contains the number of sg entries that LLDs should
    map. qc->mapped_n_elem is added to carry the original number of
    mapped sgs for unmapping.

    * The last sg of the original sg list is used to chain to extra sg
    list. The original last sg is pointed to by qc->last_sg and the
    content is stored in qc->saved_last_sg. It's restored during
    ata_sg_clean().

    * All sg walking code has been updated. Unnecessary assertions and
    checks for conditions the core layer already guarantees are removed.

    Signed-off-by: Tejun Heo
    Cc: Jens Axboe
    Signed-off-by: Jeff Garzik

    Tejun Heo
     

25 Oct, 2007

1 commit


13 Oct, 2007

3 commits

  • Currently, port configuration reporting has the following problems.

    * iomapped address is reported instead of raw address
    * report contains irrelevant fields or lacks necessary fields for
    non-SFF controllers.
    * host->irq/irq2 are there just for reporting and hacky.

    This patch implements and uses ata_port_desc() and
    ata_port_pbar_desc(). ata_port_desc() is almost identical to
    ata_ehi_push_desc() except that it takes @ap instead of @ehi, has no
    locking requirement, can only be used during host initialization and "
    " is used as separator instead of ", ". ata_port_pbar_desc() is a
    helper to ease reporting of a PCI BAR or an offsetted address into it.

    LLD pushes whatever description it wants using the above two
    functions. The accumulated description is printed on host
    registration after "[S/P]ATA max MAX_XFERMODE ".

    SFF init helpers and ata_host_activate() automatically add
    descriptions for addresses and irq respectively, so only LLDs which
    isn't standard SFF need to add custom descriptions. In many cases,
    such controllers need to report different things anyway.

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

    Tejun Heo
     
  • It was always set to ata_port_disable(). Removed the hook, and replaced
    the very few ap->ops->port_disable() callsites with direct calls to
    ata_port_disable().

    Signed-off-by: Jeff Garzik

    Jeff Garzik
     
  • * ->irq_ack() is redundant to what the irq handler already
    performs... chk-status + irq-clear. Furthermore, it is only
    called in one place, when screaming-irq-debugging is enabled,
    so we don't want to bother with a hook just for that.

    * ata_dummy_irq_on() is only ever used in drivers that have
    no callpath reaching ->irq_on(). Remove .irq_on hook from
    those drivers, and the now-unused ata_dummy_irq_on()

    Signed-off-by: Jeff Garzik

    Jeff Garzik
     

06 Aug, 2007

1 commit

  • Alan Cox suggested that the solution to the FIXMEs in pata_icside is
    to use a private postreset method to detect the lack of devices on a
    port, and in such a case, disable the interrupt for the port.

    This patch implements such a method, and removes the hard coded
    disable of port 0. Tested as working.

    Acked-by: Jeff Garzik
    Signed-off-by: Russell King

    Russell King
     

10 Jul, 2007

1 commit


12 May, 2007

3 commits


03 May, 2007

1 commit