* Add ide_do_start_stop() helper and convert ide-{floppy,tape}.c
to use it.
* Remove no longer used idefloppy_create_start_stop_cmd()
and idetape_create_load_unload_cmd().
There should be no functional changes caused by this patch.
Acked-by: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
* Set IDE_AFLAG_NO_DOORLOCK in idetape_get_mode_sense_result(), check it
in ide_tape_set_media_lock() and cleanup idetape_create_prevent_cmd().
* Set IDE_AFLAG_NO_DOORLOCK in ide_floppy_create_read_capacity_cmd() and
check it instead of IDE_AFLAG_CLIK_DRIVE in ide_floppy_set_media_lock().
* Add ide_set_media_lock() helper and convert ide-{floppy,tape}.c to use it.
* Remove no longer used ide*_create_prevent_cmd()/ide*_set_media_lock().
* Update comment in <linux/ide.h> accordingly.
Acked-by: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Add IDE_AFLAG_{SRFP,WP} drive->atapi_flags and use them
instead of ->{srfp,wp} struct ide_floppy_obj fields.
There should be no functional changes caused by this patch.
Acked-by: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
* Add ide_queue_pc_tail() and convert ide-{floppy,tape}.c to use it
instead of ide*_queue_pc_tail().
* Remove no longer used ide*_queue_pc_tail().
There should be no functional changes caused by this patch.
Acked-by: Borislav Petkov <petkovbb@gmail.com>
Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
* Move REQ_IDETAPE_* enums to <linux/ide.h>.
* Add ide_queue_pc_head() and convert ide-{floppy,tape}.c to use it
instead of ide*_queue_pc_head().
* Remove no longer used ide*_queue_pc_head().
There should be no functional changes caused by this patch.
Acked-by: Borislav Petkov <petkovbb@gmail.com>
Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
* Add IDE_PC_BUFFER_SIZE define.
* Add ide_init_pc() and convert ide-{floppy,tape}.c to use it
instead of ide*_init_pc().
* Remove no longer used IDE*_PC_BUFFER_SIZE and ide*_init_pc().
There should be no functional changes caused by this patch.
Acked-by: Borislav Petkov <petkovbb@gmail.com>
Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
* Make ->io_buffers method return number of bytes transferred.
* Use ide_end_request() instead of idefloppy_end_request()
in ide_floppy_io_buffers() and then move the call out to
ide_pc_intr().
* Add ide_io_buffers() helper and convert ide-{floppy,scsi}.c
to use it instead of ide*_io_buffers().
There should be no functional changes caused by this patch.
Acked-by: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
* Add ide_check_atapi_device() to ide-atapi.c and convert
ide-{floppy,tape}.c to use it instead of ide*_identify_device().
While at it:
* Add DRV_NAME defines to ide-{floppy,tape}.c.
Cc: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
* Add struct ide_ioctl_devset representing ioctl device setting.
* Add ide_setting_ioctl() helper for matching given ioctl
and its parameters against table of ioctl device settings.
* Convert ide_setting_ioctl() and idedisk_ioctl() to use
ide_setting_ioctl().
* Un-export ide_setting_mtx.
While at it:
* {get,set}_lba_addressing() -> {get,set}_addressing()
There should be no functional changes caused by this patch.
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
* Keep pointer to ->init_chipset method also in
struct ide_host and set it in ide_host_alloc_all().
* Add ide_pci_suspend() and ide_pci_resume() helpers
(default ->suspend and ->resume implementations).
* ->init_chipset can no longer be marked __devinit.
* Add proper PCI PM support to IDE PCI host drivers
(rz1000.c and tc86c001.c are skipped for now since
they need to be converted from using ->init_hwif
to use ->init_chipset instead).
v2:
* Cleanup CONFIG_PM #ifdef-s per akpm's suggestion.
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Rename lba_capacity_is_ok() to ata_id_is_lba_capacity_ok()
and move it to <linux/ata.h> (remove needless parens while at it).
Cc: Jeff Garzik <jgarzik@pobox.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Rename ide_id_to_hd_driveid() to ata_id_to_hd_driveid()
and move it to <linux/ata.h>.
Cc: Jeff Garzik <jgarzik@pobox.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
* Add ata_id_flush_ext_enabled() inline helper to <linux/ata.h>.
* ide_id_has_flush_cache_ext() -> ata_id_flush_ext_enabled()
The latter one also checks if the command is marked as
supported in word 83 and validity of words 83 & 86.
Cc: Jeff Garzik <jgarzik@pobox.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
* Add ata_id_flush_enabled() inline helper to <linux/ata.h>.
* ide_id_has_flush_cache() -> ata_id_flush_enabled()
The latter one also checks if the command is marked as
supported in word 83 and validity of words 83 & 86.
Cc: Jeff Garzik <jgarzik@pobox.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
All devices supporting CACHE FLUSH EXT command should also support
CACHE FLUSH command so it is sufficient to check only for CACHE FLUSH
in ide_id_has_flush_cache().
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
* Add ata_id_lba48_enabled() inline helper to <linux/ata.h>.
* idedisk_supports_lba48() -> ata_id_lba48_enabled()
The latter one also checks validity of words 83 & 86.
Cc: Jeff Garzik <jgarzik@pobox.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
* Use optimized ATA version check from Sergei in ata_id_is_sata().
* ide_dev_is_sata() -> ata_id_is_sata()
Cc: Jeff Garzik <jgarzik@pobox.com>
Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
* Remove (id[ATA_ID_FIELD_VALID] & 2) check from ide_dev_has_iordy()
(it is for validity of words 64-70, IORDY is in word 49).
* ide_dev_has_iordy() -> ata_id_has_iordy()
Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
* Use drive->media and drive->scsi to check if ->dsc_overlap
can be set by HDIO_SET_NICE ioctl in generic_ide_ioctl().
* Remove unused ->supports_dsc_overlap field from ide_driver_t.
There should be no functional changes caused by this patch.
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
* Add struct ide_devset, S_* flags, *DEVSET() & ide*_devset_*() macros.
* Add 'const struct ide_devset **settings' to ide_driver_t.
* Use 'const struct ide_devset **settings' in ide_drive_t instead of
'struct ide_settings_s *settings'. Then convert core code and device
drivers to use struct ide_devset and co.:
- device settings are no longer allocated dynamically for each device
but instead there is an unique struct ide_devset instance per setting
- device driver keeps the pointer to the table of pointers to its
settings in ide_driver_t.settings
- generic settings are kept in ide_generic_setting[]
- ide_proc_[un]register_driver(), ide_find_setting_by_name(),
ide_{read,write}_setting() and proc_ide_{read,write}_settings()
are updated accordingly
- ide*_add_settings() are removed
* Remove no longer used __ide_add_setting(), ide_add_setting(),
__ide_remove_setting() and auto_remove_settings().
* Remove no longer used TYPE_*, SETTING_*, ide_procset_t
and ide_settings_t.
* ->keep_settings, ->using_dma, ->unmask, ->noflush, ->dsc_overlap,
->nice1, ->addressing, ->wcache and ->nowerr ide_drive_t fields
can now be bitfield flags.
While at it:
* Rename ide_find_setting_by_name() to ide_find_setting().
* Rename write_wcache() to set_wcache().
There should be no functional changes caused by this patch.
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
After rework settings will be no longer created dynamically
for each device so we need to make some fixups first.
* Use set_[ksettings,unmaskirq]() as a set function for
["keepsettings","unmaskirq"] setting.
* Allow writes to ["io_32bit","unmaskirq"] settings also when
drive->no_[io_32bit,unmask] is set (this is checked later inside
set_[io_32bit,unmaskirq]() anywyay and keeps consistency with
the corresponding HDIO_SET_[32BIT,UNMASKINTR] ioctls).
* Use max possible multi sectors value (16) as an allowed max for
"multcount" setting. set_multcount() set function checks against
device's max possbile value anyway and it makes the proc setting
consistent with the corresponding HDIO_SET_MULTCOUNT ioctl.
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
* Include <linux/ata.h> directly in <linux/ide.h>
instead of through <linux/hdreg.h>.
* Include <linux/hdreg.h> only when needed.
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
* Change ide_get_paired_drive() to return NULL if peer device
is not present and update all users accordingly.
While at it:
* ide_get_paired_drive() -> ide_get_pair_dev()
* Use ide_get_pair_dev() in cs5530.c, sc1200.c and via82cxxx.c.
There should be no functional changes caused by this patch.
Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
* Make ide_busy_sleep() take timeout value as a parameter
and also allow use of AltStatus Register if requested with
altstatus parameter. Update existing users accordingly.
* Convert ide_driveid_update() and actual_try_to_identify()
to use ide_busy_sleep().
There should be no functional changes caused by this patch.
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
* Factor out HDIO_[OBSOLETE,GET]_IDENTITY ioctls handling
to ide_get_identity_ioctl().
* Use temporary buffer in ide_get_identity_ioctl() instead
of accessing drive->id directly.
* Add ide_id_to_hd_driveid() inline to convert raw id into
struct hd_driveid format (needed on big-endian).
* Use ide_id_to_hd_driveid() in ide_get_identity_ioctl(),
cleanup ide_fix_driveid() and switch ide to use use raw id.
* Remove no longer needed drive->driveid.
This leaves us with 3 users of struct hd_driveid in tree:
- arch/um/drivers/ubd_kern.c
- drivers/block/xsysace.c
- drivers/usb/storage/isd200.c
While at it:
* Use ata_id_u{32,64}() and ata_id_has_{dma,lba,iordy}() macros.
There should be no functional changes caused by this patch.
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Make drive->id an unnamed union so id can be accessed either by using
'u16 *id' or 'struct hd_driveid *driveid'. Then convert all existing
drive->id users accordingly (using 'u16 *id' when possible).
This is an intermediate step to make ide 'struct hd_driveid'-free.
While at it:
- Add missing KERN_CONTs in it821x.c.
- Use ATA_ID_WORDS and ATA_ID_*_LEN defines.
- Remove unnecessary checks for drive->id.
- s/drive_table/table/ in ide_in_drive_list().
- Cleanup ide_config_drive_speed() a bit.
- s/drive1/dev1/ & s/drive0/dev0/ in ide_undecoded_slave().
v2:
Fix typo in drivers/ide/ppc/pmac.c. (From Stephen Rothwell)
There should be no functional changes caused by this patch.
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
* 'rcu-v28-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (21 commits)
rcu: RCU-based detection of stalled CPUs for Classic RCU, fix
rcu: RCU-based detection of stalled CPUs for Classic RCU
rcu: add rcu_read_lock_sched() / rcu_read_unlock_sched()
rcu: fix sparse shadowed variable warning
doc/RCU: fix pseudocode in rcuref.txt
rcuclassic: fix compiler warning
rcu: use irq-safe locks
rcuclassic: fix compilation NG
rcu: fix locking cleanup fallout
rcu: remove redundant ACCESS_ONCE definition from rcupreempt.c
rcu: fix classic RCU locking cleanup lockdep problem
rcu: trace fix possible mem-leak
rcu: just rename call_rcu_bh instead of making it a macro
rcu: remove list_for_each_rcu()
rcu: fixes to include/linux/rcupreempt.h
rcu: classic RCU locking and memory-barrier cleanups
rcu: prevent console flood when one CPU sees another AWOL via RCU
rcu, debug: detect stalled grace periods, cleanups
rcu, debug: detect stalled grace periods
rcu classic: new algorithm for callbacks-processing(v2)
...
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6:
selinux: Fix an uninitialized variable BUG/panic in selinux_secattr_to_sid()
selinux: use default proc sid on symlinks
file capabilities: uninline cap_safe_nice
Update selinux info in MAINTAINERS and Kconfig help text
SELinux: add gitignore file for mdp script
SELinux: add boundary support and thread context assignment
securityfs: do not depend on CONFIG_SECURITY
selinux: add support for installing a dummy policy (v2)
security: add/fix security kernel-doc
selinux: Unify for- and while-loop style
selinux: conditional expression type validation was off-by-one
smack: limit privilege by label
SELinux: Fix a potentially uninitialised variable in SELinux hooks
SELinux: trivial, remove unneeded local variable
SELinux: Trivial minor fixes that change C null character style
make selinux_write_opts() static
* 'sched-v28-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (38 commits)
sched debug: add name to sched_domain sysctl entries
sched: sync wakeups vs avg_overlap
sched: remove redundant code in cpu_cgroup_create()
sched_rt.c: resch needed in rt_rq_enqueue() for the root rt_rq
cpusets: scan_for_empty_cpusets(), cpuset doesn't seem to be so const
sched: minor optimizations in wake_affine and select_task_rq_fair
sched: maintain only task entities in cfs_rq->tasks list
sched: fixup buddy selection
sched: more sanity checks on the bandwidth settings
sched: add some comments to the bandwidth code
sched: fixlet for group load balance
sched: rework wakeup preemption
CFS scheduler: documentation about scheduling policies
sched: clarify ifdef tangle
sched: fix list traversal to use _rcu variant
sched: turn off WAKEUP_OVERLAP
sched: wakeup preempt when small overlap
kernel/cpu.c: create a CPU_STARTING cpu_chain notifier
kernel/cpu.c: Move the CPU_DYING notifiers
sched: fix __load_balance_iterator() for cfq with only one task
...
* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
crypto: skcipher - Use RNG interface instead of get_random_bytes
crypto: rng - RNG interface and implementation
crypto: api - Add fips_enable flag
crypto: skcipher - Move IV generators into their own modules
crypto: cryptomgr - Test ciphers using ECB
crypto: api - Use test infrastructure
crypto: cryptomgr - Add test infrastructure
crypto: tcrypt - Add alg_test interface
crypto: tcrypt - Abort and only log if there is an error
crypto: crc32c - Use Intel CRC32 instruction
crypto: tcrypt - Avoid using contiguous pages
crypto: api - Display larval objects properly
crypto: api - Export crypto_alg_lookup instead of __crypto_alg_lookup
crypto: Kconfig - Replace leading spaces with tabs
* git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6-nmw:
GFS2: Support for I/O barriers
GFS2: Add UUID to GFS2 sb
GFS2: high time to take some time over atime
GFS2: The war on bloat
GFS2: GFS2 will panic if you misspell any mount options
GFS2: Direct IO write at end of file error
GFS2: Use an IS_ERR test rather than a NULL test
GFS2: Fix race relating to glock min-hold time
GFS2: Fix & clean up GFS2 rename
GFS2: rm on multiple nodes causes panic
GFS2: Fix metafs mounts
GFS2: Fix debugfs glock file iterator
* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6: (37 commits)
[SCSI] zfcp: fix double dbf id usage
[SCSI] zfcp: wait on SCSI work to be finished before proceeding with init dev
[SCSI] zfcp: fix erp list usage without using locks
[SCSI] zfcp: prevent fc_remote_port_delete calls for unregistered rport
[SCSI] zfcp: fix deadlock caused by shared work queue tasks
[SCSI] zfcp: put threshold data in hba trace
[SCSI] zfcp: Simplify zfcp data structures
[SCSI] zfcp: Simplify get_adapter_by_busid
[SCSI] zfcp: remove all typedefs and replace them with standards
[SCSI] zfcp: attach and release SAN nameserver port on demand
[SCSI] zfcp: remove unused references, declarations and flags
[SCSI] zfcp: Update message with input from review
[SCSI] zfcp: add queue_full sysfs attribute
[SCSI] scsi_dh: suppress comparison warning
[SCSI] scsi_dh: add Dell product information into rdac device handler
[SCSI] qla2xxx: remove the unused SCSI_QLOGIC_FC_FIRMWARE option
[SCSI] qla2xxx: fix printk format warnings
[SCSI] qla2xxx: Update version number to 8.02.01-k8.
[SCSI] qla2xxx: Ignore payload reserved-bits during RSCN processing.
[SCSI] qla2xxx: Additional residual-count corrections during UNDERRUN handling.
...
* 'for-2.6.28' of git://git.kernel.dk/linux-2.6-block: (132 commits)
doc/cdrom: Trvial documentation error, file not present
block_dev: fix kernel-doc in new functions
block: add some comments around the bio read-write flags
block: mark bio_split_pool static
block: Find bio sector offset given idx and offset
block: gendisk integrity wrapper
block: Switch blk_integrity_compare from bdev to gendisk
block: Fix double put in blk_integrity_unregister
block: Introduce integrity data ownership flag
block: revert part of d7533ad0e132f92e75c1b2eb7c26387b25a583c1
bio.h: Remove unused conditional code
block: remove end_{queued|dequeued}_request()
block: change elevator to use __blk_end_request()
gdrom: change to use __blk_end_request()
memstick: change to use __blk_end_request()
virtio_blk: change to use __blk_end_request()
blktrace: use BLKTRACE_BDEV_SIZE as the name size for setup structure
block: add lld busy state exporting interface
block: Fix blk_start_queueing() to not kick a stopped queue
include blktrace_api.h in headers_install
...
Track the memtype for RAM pages in page struct instead of using the
memtype list. This avoids the explosion in the number of entries in
memtype list (of the order of 20,000 with AGP) and makes the PAT
tracking simpler.
We are using PG_arch_1 bit in page->flags.
We still use the memtype list for non RAM pages.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Interrupt context no longer splits large page in cpa(). So we can do away
with cpa memory pool code.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: arjan@linux.intel.com
Cc: venkatesh.pallipadi@intel.com
Cc: jeremy@goop.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
remove USER from the PTE/PDE attributes for the very early identity
mapping. We overwrite these mappings with KERNEL attribute later
in the boot. Just being paranoid here as there is no need for USER bit
to be set.
If this breaks something(don't know the history), then we can simply drop
this change.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: arjan@linux.intel.com
Cc: venkatesh.pallipadi@intel.com
Cc: jeremy@goop.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This merges phase 1 of the x86 tree, which is a collection of branches:
x86/alternatives, x86/cleanups, x86/commandline, x86/crashdump,
x86/debug, x86/defconfig, x86/doc, x86/exports, x86/fpu, x86/gart,
x86/idle, x86/mm, x86/mtrr, x86/nmi-watchdog, x86/oprofile,
x86/paravirt, x86/reboot, x86/sparse-fixes, x86/tsc, x86/urgent and
x86/vmalloc
and as Ingo says: "these are the easiest, purely independent x86 topics
with no conflicts, in one nice Octopus merge".
* 'x86-v28-for-linus-phase1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (147 commits)
x86: mtrr_cleanup: treat WRPROT as UNCACHEABLE
x86: mtrr_cleanup: first 1M may be covered in var mtrrs
x86: mtrr_cleanup: print out correct type v2
x86: trivial printk fix in efi.c
x86, debug: mtrr_cleanup print out var mtrr before change it
x86: mtrr_cleanup try gran_size to less than 1M, v3
x86: mtrr_cleanup try gran_size to less than 1M, cleanup
x86: change MTRR_SANITIZER to def_bool y
x86, debug printouts: IOMMU setup failures should not be KERN_ERR
x86: export set_memory_ro and set_memory_rw
x86: mtrr_cleanup try gran_size to less than 1M
x86: mtrr_cleanup prepare to make gran_size to less 1M
x86: mtrr_cleanup safe to get more spare regs now
x86_64: be less annoying on boot, v2
x86: mtrr_cleanup hole size should be less than half of chunk_size, v2
x86: add mtrr_cleanup_debug command line
x86: mtrr_cleanup optimization, v2
x86: don't need to go to chunksize to 4G
x86_64: be less annoying on boot
x86, olpc: fix endian bug in openfirmware workaround
...
* '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