libata-sff.c checks for legacy mode by testing if both primary and
secondary ports on a controller are in legacy mode and selects legacy
if either one is. However on some south bridge chips (e.g AMD
SB600/SB700) the secondary port is not wired, and when it is disabled
by setting the disable bit in the PCI header it appears as a fixed
legacy port.

Prevent incorrect detection by not testing ports that are marked as
'dummy'

tj: Addressed Sergei's review points.  Other style edits.
Signed-off-by: NDarren Stevens <darren@stevens-zone.net>
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>

For Atari Falcon PATA support we need to check the current command
in its ->sff_data_xfer method.  Update core code and all users
accordingly.

There should be no functional changes caused by this patch.
Signed-off-by: NBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: NTejun Heo <tj@kernel.org>

The bulk of ATA host state machine is implemented by
ata_sff_hsm_move().  The function is called from either the interrupt
handler or, if polling, a work item.  Unlike from the interrupt path,
the polling path calls the function without holding the host lock and
ata_sff_hsm_move() selectively grabs the lock.

This is completely broken.  If an IRQ triggers while polling is in
progress, the two can easily race and end up accessing the hardware
and updating state machine state at the same time.  This can put the
state machine in an illegal state and lead to a crash like the
following.

  kernel BUG at drivers/ata/libata-sff.c:1302!
  invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN
  Modules linked in:
  CPU: 1 PID: 10679 Comm: syz-executor Not tainted 4.5.0-rc1+ #300
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
  task: ffff88002bd00000 ti: ffff88002e048000 task.ti: ffff88002e048000
  RIP: 0010:[<ffffffff83a83409>]  [<ffffffff83a83409>] ata_sff_hsm_move+0x619/0x1c60
  ...
  Call Trace:
   <IRQ>
   [<ffffffff83a84c31>] __ata_sff_port_intr+0x1e1/0x3a0 drivers/ata/libata-sff.c:1584
   [<ffffffff83a85611>] ata_bmdma_port_intr+0x71/0x400 drivers/ata/libata-sff.c:2877
   [<     inline     >] __ata_sff_interrupt drivers/ata/libata-sff.c:1629
   [<ffffffff83a85bf3>] ata_bmdma_interrupt+0x253/0x580 drivers/ata/libata-sff.c:2902
   [<ffffffff81479f98>] handle_irq_event_percpu+0x108/0x7e0 kernel/irq/handle.c:157
   [<ffffffff8147a717>] handle_irq_event+0xa7/0x140 kernel/irq/handle.c:205
   [<ffffffff81484573>] handle_edge_irq+0x1e3/0x8d0 kernel/irq/chip.c:623
   [<     inline     >] generic_handle_irq_desc include/linux/irqdesc.h:146
   [<ffffffff811a92bc>] handle_irq+0x10c/0x2a0 arch/x86/kernel/irq_64.c:78
   [<ffffffff811a7e4d>] do_IRQ+0x7d/0x1a0 arch/x86/kernel/irq.c:240
   [<ffffffff86653d4c>] common_interrupt+0x8c/0x8c arch/x86/entry/entry_64.S:520
   <EOI>
   [<     inline     >] rcu_lock_acquire include/linux/rcupdate.h:490
   [<     inline     >] rcu_read_lock include/linux/rcupdate.h:874
   [<ffffffff8164b4a1>] filemap_map_pages+0x131/0xba0 mm/filemap.c:2145
   [<     inline     >] do_fault_around mm/memory.c:2943
   [<     inline     >] do_read_fault mm/memory.c:2962
   [<     inline     >] do_fault mm/memory.c:3133
   [<     inline     >] handle_pte_fault mm/memory.c:3308
   [<     inline     >] __handle_mm_fault mm/memory.c:3418
   [<ffffffff816efb16>] handle_mm_fault+0x2516/0x49a0 mm/memory.c:3447
   [<ffffffff8127dc16>] __do_page_fault+0x376/0x960 arch/x86/mm/fault.c:1238
   [<ffffffff8127e358>] trace_do_page_fault+0xe8/0x420 arch/x86/mm/fault.c:1331
   [<ffffffff8126f514>] do_async_page_fault+0x14/0xd0 arch/x86/kernel/kvm.c:264
   [<ffffffff86655578>] async_page_fault+0x28/0x30 arch/x86/entry/entry_64.S:986

Fix it by ensuring that the polling path is holding the host lock
before entering ata_sff_hsm_move() so that all hardware accesses and
state updates are performed under the host lock.
Signed-off-by: NTejun Heo <tj@kernel.org>
Reported-and-tested-by: NDmitry Vyukov <dvyukov@google.com>
Link: http://lkml.kernel.org/g/CACT4Y+b_JsOxJu2EZyEf+mOXORc_zid5V1-pLZSroJVxyWdSpw@mail.gmail.com
Cc: stable@vger.kernel.org

ata_sff_hsm_move() triggers BUG if it sees a host state machine state
that it dind't expect.  The risk for data corruption when the
condition occurs is low as it's highly unlikely that it would lead to
spurious completion of commands.  The BUG occasionally triggered for
subtle race conditions in the driver.  Let's downgrade it to WARN so
that it doesn't kill the machine unnecessarily.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Dmitry Vyukov <dvyukov@google.com>

Replace occurences of the pci api by appropriate call to the dma api.

A simplified version of the semantic patch that finds this problem is as
follows: (http://coccinelle.lip6.fr)

@deprecated@
idexpression id;
position p;
@@

(
  pci_dma_supported@p ( id, ...)
|
  pci_alloc_consistent@p ( id, ...)
)

@bad1@
idexpression id;
position deprecated.p;
@@
...when != &id->dev
   when != pci_get_drvdata ( id )
   when != pci_enable_device ( id )
(
  pci_dma_supported@p ( id, ...)
|
  pci_alloc_consistent@p ( id, ...)
)

@depends on !bad1@
idexpression id;
expression direction;
position deprecated.p;
@@

(
- pci_dma_supported@p ( id,
+ dma_supported ( &id->dev,
...
+ , GFP_ATOMIC
  )
|
- pci_alloc_consistent@p ( id,
+ dma_alloc_coherent ( &id->dev,
...
+ , GFP_ATOMIC
  )
)
Signed-off-by: NQuentin Lambert <lambert.quentin@gmail.com>
Signed-off-by: NTejun Heo <tj@kernel.org>

It is possible for ata_sff_flush_pio_task() to set ap->hsm_task_state to
HSM_ST_IDLE in between the time __ata_sff_port_intr() checks for HSM_ST_IDLE
and before it calls ata_sff_hsm_move() causing ata_sff_hsm_move() to BUG().

This problem is hard to reproduce making this patch hard to verify, but this
fix will prevent the race.

I have not been able to reproduce the problem, but here is a crash dump from
a 2.6.32 kernel.

On examining the ata port's state, its hsm_task_state field has a value of HSM_ST_IDLE:

crash> struct ata_port.hsm_task_state ffff881c1121c000
  hsm_task_state = 0

Normally, this should not be possible as ata_sff_hsm_move() was called from ata_sff_host_intr(),
which checks hsm_task_state and won't call ata_sff_hsm_move() if it has a HSM_ST_IDLE value.

PID: 11053  TASK: ffff8816e846cae0  CPU: 0   COMMAND: "sshd"
 #0 [ffff88008ba03960] machine_kexec at ffffffff81038f3b
 #1 [ffff88008ba039c0] crash_kexec at ffffffff810c5d92
 #2 [ffff88008ba03a90] oops_end at ffffffff8152b510
 #3 [ffff88008ba03ac0] die at ffffffff81010e0b
 #4 [ffff88008ba03af0] do_trap at ffffffff8152ad74
 #5 [ffff88008ba03b50] do_invalid_op at ffffffff8100cf95
 #6 [ffff88008ba03bf0] invalid_op at ffffffff8100bf9b
    [exception RIP: ata_sff_hsm_move+317]
    RIP: ffffffff813a77ad  RSP: ffff88008ba03ca0  RFLAGS: 00010097
    RAX: 0000000000000000  RBX: ffff881c1121dc60  RCX: 0000000000000000
    RDX: ffff881c1121dd10  RSI: ffff881c1121dc60  RDI: ffff881c1121c000
    RBP: ffff88008ba03d00   R8: 0000000000000000   R9: 000000000000002e
    R10: 000000000001003f  R11: 000000000000009b  R12: ffff881c1121c000
    R13: 0000000000000000  R14: 0000000000000050  R15: ffff881c1121dd78
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 #7 [ffff88008ba03d08] ata_sff_host_intr at ffffffff813a7fbd
 #8 [ffff88008ba03d38] ata_sff_interrupt at ffffffff813a821e
 #9 [ffff88008ba03d78] handle_IRQ_event at ffffffff810e6ec0
--- <IRQ stack> ---
    [exception RIP: pipe_poll+48]
    RIP: ffffffff81192780  RSP: ffff880f26d459b8  RFLAGS: 00000246
    RAX: 0000000000000000  RBX: ffff880f26d459c8  RCX: 0000000000000000
    RDX: 0000000000000001  RSI: 0000000000000000  RDI: ffff881a0539fa80
    RBP: ffffffff8100bb8e   R8: ffff8803b23324a0   R9: 0000000000000000
    R10: ffff880f26d45dd0  R11: 0000000000000008  R12: ffffffff8109b646
    R13: ffff880f26d45948  R14: 0000000000000246  R15: 0000000000000246
    ORIG_RAX: ffffffffffffff10  CS: 0010  SS: 0018
    RIP: 00007f26017435c3  RSP: 00007fffe020c420  RFLAGS: 00000206
    RAX: 0000000000000017  RBX: ffffffff8100b072  RCX: 00007fffe020c45c
    RDX: 00007f2604a3f120  RSI: 00007f2604a3f140  RDI: 000000000000000d
    RBP: 0000000000000000   R8: 00007fffe020e570   R9: 0101010101010101
    R10: 0000000000000000  R11: 0000000000000246  R12: 00007fffe020e5f0
    R13: 00007fffe020e5f4  R14: 00007f26045f373c  R15: 00007fffe020e5e0
    ORIG_RAX: 0000000000000017  CS: 0033  SS: 002b

Somewhere between the ata_sff_hsm_move() check and the ata_sff_host_intr() check, the value changed.
On examining the other cpus to see what else was running, another cpu was running the error handler
routines:

PID: 326    TASK: ffff881c11014aa0  CPU: 1   COMMAND: "scsi_eh_1"
 #0 [ffff88008ba27e90] crash_nmi_callback at ffffffff8102fee6
 #1 [ffff88008ba27ea0] notifier_call_chain at ffffffff8152d515
 #2 [ffff88008ba27ee0] atomic_notifier_call_chain at ffffffff8152d57a
 #3 [ffff88008ba27ef0] notify_die at ffffffff810a154e
 #4 [ffff88008ba27f20] do_nmi at ffffffff8152b1db
 #5 [ffff88008ba27f50] nmi at ffffffff8152aaa0
    [exception RIP: _spin_lock_irqsave+47]
    RIP: ffffffff8152a1ff  RSP: ffff881c11a73aa0  RFLAGS: 00000006
    RAX: 0000000000000001  RBX: ffff881c1121deb8  RCX: 0000000000000000
    RDX: 0000000000000246  RSI: 0000000000000020  RDI: ffff881c122612d8
    RBP: ffff881c11a73aa0   R8: ffff881c17083800   R9: 0000000000000000
    R10: 0000000000000000  R11: 0000000000000000  R12: ffff881c1121c000
    R13: 000000000000001f  R14: ffff881c1121dd50  R15: ffff881c1121dc60
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0000
--- <NMI exception stack> ---
 #6 [ffff881c11a73aa0] _spin_lock_irqsave at ffffffff8152a1ff
 #7 [ffff881c11a73aa8] ata_exec_internal_sg at ffffffff81396fb5
 #8 [ffff881c11a73b58] ata_exec_internal at ffffffff81397109
 #9 [ffff881c11a73bd8] atapi_eh_request_sense at ffffffff813a34eb

Before it tried to acquire a spinlock, ata_exec_internal_sg() called ata_sff_flush_pio_task().
This function will set ap->hsm_task_state to HSM_ST_IDLE, and has no locking around setting this
value. ata_sff_flush_pio_task() can then race with the interrupt handler and potentially set
HSM_ST_IDLE at a fatal moment, which will trigger a kernel BUG.

v2: Fixup comment in ata_sff_flush_pio_task()

tj: Further updated comment.  Use ap->lock instead of shost lock and
    use the [un]lock_irq variant instead of the irqsave/restore one.
Signed-off-by: NDavid Milburn <dmilburn@redhat.com>
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: stable@vger.kernel.org

Currently, ata_sff_softreset is skipped for controllers with no ctl port.
But that also skips ata_sff_dev_classify required for device detection.
This means that libata is currently broken on controllers with no ctl port.

No device connected:
[    1.872480] pata_isapnp 01:01.02: activated
[    1.889823] scsi2 : pata_isapnp
[    1.890109] ata3: PATA max PIO0 cmd 0x1e8 ctl 0x0 irq 11
[    6.888110] ata3.01: qc timeout (cmd 0xec)
[    6.888179] ata3.01: failed to IDENTIFY (I/O error, err_mask=0x5)
[   16.888085] ata3.01: qc timeout (cmd 0xec)
[   16.888147] ata3.01: failed to IDENTIFY (I/O error, err_mask=0x5)
[   46.888086] ata3.01: qc timeout (cmd 0xec)
[   46.888148] ata3.01: failed to IDENTIFY (I/O error, err_mask=0x5)
[   51.888100] ata3.00: qc timeout (cmd 0xec)
[   51.888160] ata3.00: failed to IDENTIFY (I/O error, err_mask=0x5)
[   61.888079] ata3.00: qc timeout (cmd 0xec)
[   61.888141] ata3.00: failed to IDENTIFY (I/O error, err_mask=0x5)
[   91.888089] ata3.00: qc timeout (cmd 0xec)
[   91.888152] ata3.00: failed to IDENTIFY (I/O error, err_mask=0x5)

ATAPI device connected:
[    1.882061] pata_isapnp 01:01.02: activated
[    1.893430] scsi2 : pata_isapnp
[    1.893719] ata3: PATA max PIO0 cmd 0x1e8 ctl 0x0 irq 11
[    6.892107] ata3.01: qc timeout (cmd 0xec)
[    6.892171] ata3.01: failed to IDENTIFY (I/O error, err_mask=0x5)
[   16.892079] ata3.01: qc timeout (cmd 0xec)
[   16.892138] ata3.01: failed to IDENTIFY (I/O error, err_mask=0x5)
[   46.892079] ata3.01: qc timeout (cmd 0xec)
[   46.892138] ata3.01: failed to IDENTIFY (I/O error, err_mask=0x5)
[   46.908586] ata3.00: ATAPI: ACER CD-767E/O, V1.5X, max PIO2, CDB intr
[   46.924570] ata3.00: configured for PIO0 (device error ignored)
[   46.926295] scsi 2:0:0:0: CD-ROM            ACER     CD-767E/O        1.5X PQ: 0 ANSI: 5
[   46.984519] sr0: scsi3-mmc drive: 6x/6x xa/form2 tray
[   46.984592] cdrom: Uniform CD-ROM driver Revision: 3.20

So don't skip ata_sff_softreset, just skip the reset part of ata_bus_softreset
if the ctl port is not available.

This makes IDE port on ES968 behave correctly:

No device connected:
[    4.670888] pata_isapnp 01:01.02: activated
[    4.673207] scsi host2: pata_isapnp
[    4.673675] ata3: PATA max PIO0 cmd 0x1e8 ctl 0x0 irq 11
[    7.081840] Adding 2541652k swap on /dev/sda2.  Priority:-1 extents:1 across:2541652k

ATAPI device connected:
[    4.704362] pata_isapnp 01:01.02: activated
[    4.706620] scsi host2: pata_isapnp
[    4.706877] ata3: PATA max PIO0 cmd 0x1e8 ctl 0x0 irq 11
[    4.872782] ata3.00: ATAPI: ACER CD-767E/O, V1.5X, max PIO2, CDB intr
[    4.888673] ata3.00: configured for PIO0 (device error ignored)
[    4.893984] scsi 2:0:0:0: CD-ROM            ACER     CD-767E/O        1.5X PQ: 0 ANSI: 5
[    7.015578] Adding 2541652k swap on /dev/sda2.  Priority:-1 extents:1 across:2541652k
Signed-off-by: NOndrej Zary <linux@rainbow-software.org>
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: stable@vger.kernel.org

Ever since v2.6.19 the code contains a check for CONFIG_NO_ATA_LEGACY.
But that macro has never been defined. Apparently no one ran into
problems on platforms that do not support compatibility mode. So remove
this code that has been dead for over seven years.
Signed-off-by: NPaul Bolle <pebolle@tiscali.nl>
Signed-off-by: NTejun Heo <tj@kernel.org>

Jeff moved on to a greener pasture.

 s/Maintained by: Jeff Garzik/Maintained by: Tejun Heo/g
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Jeff Garzik <jgarzik@pobox.com>

Acked-by: NJeff Garzik <jgarzik@redhat.com>
Signed-off-by: NCong Wang <amwang@redhat.com>

atapi_pio_bytes() uses bare numbers for the ATAPI interrupt reason bits despite
these are #define'd in <linux/ata.h>.
Signed-off-by: NSergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

fix these errors:
drivers/ata/libata-sff.c:2538:3: error: implicit declaration of function
'ata_pci_bmdma_prepare_host'
drivers/ata/libata-sff.c:2549:40: error: 'ata_bmdma_interrupt'
undeclared (first use in this function)
Signed-off-by: NAlexander Beregalov <a.beregalov@gmail.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

A pending cleanup will mean that module.h won't be implicitly
everywhere anymore.  Make sure the modular drivers in the ide dir
are actually calling out for <module.h> explicitly in advance.
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>

Always use ata_sff_data_xfer32() in ata_sff_data_xfer_noirq()
so the latter can be also used for host controllers supporting
32-bit PIO operations.

It is a completely safe thing to do because if 32-bit PIO is
not supported or enabled ata_sff_data_xfer32() will fallback
to a standard method.
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Turn both helpers (which are used only during LLDs initialization
time and thus are not performance sensitive) into wrappers around
the new ata_pci_init_one() function, this cuts 20 LOC and saves
~1.1k of the output code size (x86-64):

 text    data     bss     dec     hex filename
  21392       0      19   21411    53a3 drivers/ata/libata-sff.o.before
  20256       0      19   20275    4f33 drivers/ata/libata-sff.o.after
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

ata_sff_data_xfer[32]() use pad area if the transfer size isn't
multiple of transfer size; however, this area wasn't cleared and
garbage data in pad area could be transferred to the device.  Make
sure the pad area is cleared.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Lei Ming <tom.leiming@gmail.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Cleanup sff_pio_task_link when a command is cancel while the
pio_task thread has been scheduled.
Signed-off-by: NGwendal Grignou <gwendal@google.com>
Acked-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NJeff Garzik <jgarzik@pobox.com>

Saves text by removing nearly duplicated text format strings by
creating ata_<foo>_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: NJoe Perches <joe@perches.com>
Signed-off-by: NJeff Garzik <jgarzik@pobox.com>

Saves a bit of text as the call takes fewer args.

Coalesce a few formats.
Convert a few bare printks to pr_cont.

$ size drivers/ata/built-in.o*
   text	   data	    bss	    dec	    hex	filename
 558429	  73893	 117864	 750186	  b726a	drivers/ata/built-in.o.allyesconfig.new
 559574	  73893	 117888	 751355	  b76fb	drivers/ata/built-in.o.allyesconfig.old
 149567	  14689	   4220	 168476	  2921c	drivers/ata/built-in.o.defconfig.new
 149851	  14689	   4220	 168760	  29338	drivers/ata/built-in.o.defconfig.old
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NJeff Garzik <jgarzik@pobox.com>

This is a cosmetic change to prevent libata-sff adding irq
descriptions to dummy ports, since the information, while largely
unused, is erroneous.
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>
Signed-off-by: NJeff Garzik <jgarzik@pobox.com>

Fixes generated by 'codespell' and manually reviewed.
Signed-off-by: NLucas De Marchi <lucas.demarchi@profusion.mobi>

This patch adds ata_sff_queue_work() & ata_sff_queue_delayed_work() routine in
libata-sff.c file. This routine can be used by ata drivers to use ata_sff_wq.
Signed-off-by: NViresh Kumar <viresh.kumar@st.com>
Acked-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NJeff Garzik <jgarzik@pobox.com>

While separating out BMDMA irq handler from SFF, commit c3b28894
(libata-sff: separate out BMDMA irq handler) incorrectly made
__ata_sff_port_intr() consider an IRQ to be an idle one if the host
state was transitioned to HSM_ST_ERR by ata_bmdma_port_intr().

This makes BMDMA drivers ignore IRQs reporting host bus error which
leads to timeouts instead of triggering EH immediately.  Fix it by
making __ata_sff_port_intr() consider the IRQ to be an idle one iff
the state is HSM_ST_IDLE.  This is equivalent to adding HSM_ST_ERR to
the "break"ing case but less error-prone.
Signed-off-by: NTejun Heo <tj@kernel.org>
Reported-by: NAntonio Toma <antonio.toma@gmail.com>
Cc: stable@kernel.org
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

cancel_rearming_delayed_work[queue]() has been superceded by
cancel_delayed_work_sync() quite some time ago.  Convert all the
in-kernel users.  The conversions are completely equivalent and
trivial.
Signed-off-by: NTejun Heo <tj@kernel.org>
Acked-by: N"David S. Miller" <davem@davemloft.net>
Acked-by: NGreg Kroah-Hartman <gregkh@suse.de>
Acked-by: NEvgeniy Polyakov <zbr@ioremap.net>
Cc: Jeff Garzik <jgarzik@pobox.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Mauro Carvalho Chehab <mchehab@infradead.org>
Cc: netdev@vger.kernel.org
Cc: Anton Vorontsov <cbou@mail.ru>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Neil Brown <neilb@suse.de>
Cc: Alex Elder <aelder@sgi.com>
Cc: xfs-masters@oss.sgi.com
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: netfilter-devel@vger.kernel.org
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: linux-nfs@vger.kernel.org

Add optional @ap argument to ata_wait_register() and replace msleep()
calls with ata_msleep() which take optional @ap in addition to the
duration.  These will be used to implement EH exclusion.

This patch doesn't cause any behavior difference.
Signed-off-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

This build error showed up in linux-next tag next-20100820 for ia64:

WARNING: vmlinux.o(.init.text+0x4a952): Section mismatch in reference from the function ata_init() to the function .exit.text:ata_sff_exit()
The function __init ata_init() references
a function __exit ata_sff_exit().
This is often seen when error handling in the init function
uses functionality in the exit path.
The fix is often to remove the __exit annotation of
ata_sff_exit() so it may be used outside an exit section.

Sure enough, dropping the __exit fixes the problem.
Signed-off-by: NTony Luck <tony.luck@intel.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Add WQ_MEM_RECLAIM flag which currently maps to WQ_RESCUER, mark
WQ_RESCUER as internal and replace all external WQ_RESCUER usages to
WQ_MEM_RECLAIM.

This makes the API users express the intent of the workqueue instead
of indicating the internal mechanism used to guarantee forward
progress.  This is also to make it cleaner to add more semantics to
WQ_MEM_RECLAIM.  For example, if deemed necessary, memory reclaim
workqueues can be made highpri.

This patch doesn't introduce any functional change.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Jeff Garzik <jgarzik@pobox.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>

Keep track of the link on the which the current request is in progress.
It allows support of links behind port multiplier.

Not all libata-sff is PMP compliant. Code for native BMDMA controller
does not take in accound PMP.

Tested on Marvell 7042 and Sil7526.
Signed-off-by: NGwendal Grignou <gwendal@google.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Commit 978c0666 (libata: Remove excess delay in the tf_load path)
removed ata_wait_idle() from ata_sff_tf_load() and via_tf_load().
This caused obscure detection problems in sata_sil.

  https://bugzilla.kernel.org/show_bug.cgi?id=16606

The commit was pure performance optimization.  Revert it for now.
Reported-by: NDieter Plaetinck <dieter@plaetinck.be>
Reported-by: NJan Beulich <JBeulich@novell.com>
Bisected-by: Ngianluca <gianluca@sottospazio.it>
Cc: stable@kernel.org
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Remove harmful BUG_ON() from ata_bmdma_qc_issue(),
as it casts too wide of a net and breaks sata_mv.
It also crashes the kernel while doing the BUG_ON().

There's already a WARN_ON_ONCE() further down to catch
the case of POLLING for a BMDMA operation.
Signed-off-by: NMark Lord <mlord@pobox.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>
Cc: stable@kernel.org

libata has two concurrency related limitations.

a. ata_wq which is used for polling PIO has single thread per CPU.  If
   there are multiple devices doing polling PIO on the same CPU, they
   can't be executed simultaneously.

b. ata_aux_wq which is used for SCSI probing has single thread.  In
   cases where SCSI probing is stalled for extended period of time
   which is possible for ATAPI devices, this will stall all probing.

#a is solved by increasing maximum concurrency of ata_wq.  Please note
that polling PIO might be used under allocation path and thus needs to
be served by a separate wq with a rescuer.

#b is solved by using the default wq instead and achieving exclusion
via per-port mutex.
Signed-off-by: NTejun Heo <tj@kernel.org>
Acked-by: NJeff Garzik <jgarzik@pobox.com>

Make BMDMA optional depending on new config variable CONFIG_ATA_BMDMA.
In Kconfig, drivers are grouped into five groups - non-SFF native, SFF
w/ custom DMA interface, SFF w/ BMDMA, PIO-only SFF, and generic
fallback / legacy ones.  Kconfig and Makefile are reorganized
according to the groups and ordered alphabetically inside each group.

ata_ioports.bmdma_addr and ata_port.bmdma_prd[_dma] are put into
CONFIG_ATA_BMDMA, as are all bmdma related ops, variables and
functions.

This increase the binary size slightly when BMDMA is enabled but on
both native-only and PIO-only configurations the size is slightly
reduced.  Either way, the size difference is insignificant.  This
change is more meaningful to signify the separation between SFF and
BMDMA and as a tool to verify the separation.
Signed-off-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

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: NTejun Heo <tj@kernel.org>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

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: NTejun Heo <tj@kernel.org>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

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: NTejun Heo <tj@kernel.org>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

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: NTejun Heo <tj@kernel.org>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

struct ata_prd and ap->prd are BMDMA specific.  Add bmdma_ prefix to
them and move them inside CONFIG_ATA_SFF.
Signed-off-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

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: NTejun Heo <tj@kernel.org>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

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: NTejun Heo <tj@kernel.org>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>