Describe NUMA node symlink created for CPUs when CONFIG_NUMA is set.
Signed-off-by: Alex Chiang <achiang@hp.com>
Cc: Greg KH <greg@kroah.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Gary Hade <garyhade@us.ibm.com>
Cc: Badari Pulavarty <pbadari@us.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Rientjes <rientjes@google.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit c04fc586c (mm: show node to memory section relationship with
symlinks in sysfs) created symlinks from nodes to memory sections, e.g.
/sys/devices/system/node/node1/memory135 -> ../../memory/memory135
If you're examining the memory section though and are wondering what node
it might belong to, you can find it by grovelling around in sysfs, but
it's a little cumbersome.
Add a reverse symlink for each memory section that points back to the
node to which it belongs.
Signed-off-by: Alex Chiang <achiang@hp.com>
Cc: Gary Hade <garyhade@us.ibm.com>
Cc: Badari Pulavarty <pbadari@us.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Greg KH <greg@kroah.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Cc: David Rientjes <rientjes@google.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (151 commits)
powerpc: Fix usage of 64-bit instruction in 32-bit altivec code
MAINTAINERS: Add PowerPC patterns
powerpc/pseries: Track previous CPPR values to correctly EOI interrupts
powerpc/pseries: Correct pseries/dlpar.c build break without CONFIG_SMP
powerpc: Make "intspec" pointers in irq_host->xlate() const
powerpc/8xx: DTLB Miss cleanup
powerpc/8xx: Remove DIRTY pte handling in DTLB Error.
powerpc/8xx: Start using dcbX instructions in various copy routines
powerpc/8xx: Restore _PAGE_WRITETHRU
powerpc/8xx: Add missing Guarded setting in DTLB Error.
powerpc/8xx: Fixup DAR from buggy dcbX instructions.
powerpc/8xx: Tag DAR with 0x00f0 to catch buggy instructions.
powerpc/8xx: Update TLB asm so it behaves as linux mm expects.
powerpc/8xx: Invalidate non present TLBs
powerpc/pseries: Serialize cpu hotplug operations during deactivate Vs deallocate
pseries/pseries: Add code to online/offline CPUs of a DLPAR node
powerpc: stop_this_cpu: remove the cpu from the online map.
powerpc/pseries: Add kernel based CPU DLPAR handling
sysfs/cpu: Add probe/release files
powerpc/pseries: Kernel DLPAR Infrastructure
...
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/davej/cpufreq:
[ACPI/CPUFREQ] Introduce bios_limit per cpu cpufreq sysfs interface
[CPUFREQ] make internal cpufreq_add_dev_* static
[CPUFREQ] use an enum for speedstep processor identification
[CPUFREQ] Document units for transition latency
[CPUFREQ] Use global sysfs cpufreq structure for conservative governor tunings
[CPUFREQ] Documentation: ABI: /sys/devices/system/cpu/cpu#/cpufreq/
[CPUFREQ] powernow-k6: set transition latency value so ondemand governor can be used
[CPUFREQ] cpumask: don't put a cpumask on the stack in x86...cpufreq/powernow-k8.c
Accroding commit 0994375e, which is adding remove_id sysfs attr
for pci drivers, for management tools dynamically bind/unbind
a pci/usb devices to a specified drivers; with this patch,
the management tools can be simplied.
And the original code didn't handle the failure of
usb_create_newid_file, fixed in this patch.
Signed-off-by: CHENG Renquan <rqcheng@smu.edu.sg>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Add the wusb_phy_rate sysfs file to Wireless USB host controllers. This
sets the maximum PHY rate that will be used for all connected devices.
Signed-off-by: David Vrabel <david.vrabel@csr.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6: (222 commits)
[SCSI] zfcp: Remove flag ZFCP_STATUS_FSFREQ_TMFUNCNOTSUPP
[SCSI] zfcp: Activate fc4s attributes for zfcp in FC transport class
[SCSI] zfcp: Block scsi_eh thread for rport state BLOCKED
[SCSI] zfcp: Update FSF error reporting
[SCSI] zfcp: Improve ELS ADISC handling
[SCSI] zfcp: Simplify handling of ct and els requests
[SCSI] zfcp: Remove ZFCP_DID_MASK
[SCSI] zfcp: Move WKA port to zfcp FC code
[SCSI] zfcp: Use common code definitions for FC CT structs
[SCSI] zfcp: Use common code definitions for FC ELS structs
[SCSI] zfcp: Update FCP protocol related code
[SCSI] zfcp: Dont fail SCSI commands when transitioning to blocked fc_rport
[SCSI] zfcp: Assign scheduled work to driver queue
[SCSI] zfcp: Remove STATUS_COMMON_REMOVE flag as it is not required anymore
[SCSI] zfcp: Implement module unloading
[SCSI] zfcp: Merge trace code for fsf requests in one function
[SCSI] zfcp: Access ports and units with container_of in sysfs code
[SCSI] zfcp: Remove suspend callback
[SCSI] zfcp: Remove global config_mutex
[SCSI] zfcp: Replace local reference counting with common kref
...
Version 3 of this patch is updated with documentation added to
Documentation/ABI. There are no changes to any of the C code from v2
of the patch.
In order to support kernel DLPAR of CPU resources we need to provide an
interface to add (probe) and remove (release) the resource from the system.
This patch Creates new generic probe and release sysfs files to facilitate
cpu probe/release. The probe/release interface provides for allowing each
arch to supply their own routines for implementing the backend of adding
and removing cpus to/from the system.
This also creates the powerpc specific stubs to handle the arch callouts
from writes to the sysfs files.
The creation and use of these files is regulated by the
CONFIG_ARCH_CPU_PROBE_RELEASE option so that only architectures that need the
capability will have the files created.
Signed-off-by: Nathan Fontenot <nfont@austin.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This is a complex interface and is already described in
Documentation/cpu-freq/, especially in the user-guide.txt file.
No need to copy/paste all that information. Let's just alert the reader
to the presence of the user-guide.
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Dave Jones <davej@redhat.com>
Describe NUMA node symlink created for CPUs when CONFIG_NUMA is set.
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Add brief descriptions for the following sysfs files:
/sys/devices/system/cpu/cpu#/topology/core_id
/sys/devices/system/cpu/cpu#/topology/core_siblings
/sys/devices/system/cpu/cpu#/topology/core_siblings_list
/sys/devices/system/cpu/cpu#/topology/physical_package_id
/sys/devices/system/cpu/cpu#/topology/thread_siblings
/sys/devices/system/cpu/cpu#/topology/thread_siblings_list
The descriptions in Documentation/cputopology.txt weren't very
informative, so I attempted a better description based on code
reading and hopeful guessing.
Updated Documentation/cputopology.txt with the better descriptions and
fixed some style issues.
Cc: Mike Travis <travis@sgi.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Add brief descriptions for the following sysfs files:
/sys/devices/system/cpu/kernel_max
/sys/devices/system/cpu/offline
/sys/devices/system/cpu/online
/sys/devices/system/cpu/possible
/sys/devices/system/cpu/present
Excerpted the relevant information from Documentation/cputopology.txt
and pointed back to cputopology.txt as the authoritative source of
information.
Cc: Mike Travis <travis@sgi.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This interface has been around for a long time, but hasn't been
officially documented.
Document the top level sysfs directory for CPU attributes.
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Rename sysfs-devices-cache_disable to sysfs-devices-system-cpu, in
order to keep a stricter correlation between a sysfs directory and
its documentation.
Reported-by: David Rientjes <rientjes@google.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
When collecting slub stats for particular workloads, it's necessary to
collect each statistic for all caches before the job is even started
because the counters are usually greater than zero just from boot and
initialization.
This allows a statistic to be cleared on each cpu by writing '0' to its
sysfs file. This creates a baseline for statistics of interest before
the workload is started.
Setting a statistic to a particular value is not supported, so all values
written to these files other than '0' returns -EINVAL.
Cc: Christoph Lameter <cl@linux-foundation.org>
Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
The usb_host class is no more. Rename its documentation file (which
only contained WUSB specific files) to .../sysfs-class-uwb_rc-wusbhc.
Signed-off-by: David Vrabel <david.vrabel@csr.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Add usage_count attribute to each logical drive at
/sys/devices/<dev>/ccissX/cXdY/usage_count for controller X,
logical drive Y. The usage count is the number of times
the device has currently been opened.
Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
and change get rid of some magic numbers in raid lavel decoding.
Add raid_level attribute to each logical drive at
/sys/devices/<dev>/ccissX/cXdY/raid_level for controller X,
logical drive Y
Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Add lunid attribute to each logical drive at
/sys/devices/<dev>/ccissX/cXdY/lunid for controller X,
logical drive Y
Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Added /sys/bus/pci/devices/<dev>/ccissX/rescan sysfs entry used
to kick off a rescan that discovers logical drive topology changes.
Signed-off-by: Andrew Patterson <andrew.patterson@hp.com>
Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>
Acked-by: Mike Miller <mike.miller@hp.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6: (119 commits)
ACPI: don't pass handle for fixed hardware notifications
ACPI: remove null pointer checks in deferred execution path
ACPI: simplify deferred execution path
acerhdf: additional BIOS versions
acerhdf: convert to dev_pm_ops
acerhdf: fix fan control for AOA150 model
thermal: add missing Kconfig dependency
acpi: switch /proc/acpi/{debug_layer,debug_level} to seq_file
hp-wmi: fix rfkill memory leak on unload
ACPI: remove unnecessary #ifdef CONFIG_DMI
ACPI: linux/acpi.h should not include linux/dmi.h
hwmon driver for ACPI 4.0 power meters
topstar-laptop: add new driver for hotkeys support on Topstar N01
thinkpad_acpi: fix rfkill memory leak on unload
thinkpad-acpi: report brightness events when required
thinkpad-acpi: don't poll by default any of the reserved hotkeys
thinkpad-acpi: Fix procfs hotkey reset command
thinkpad-acpi: deprecate hotkey_bios_mask
thinkpad-acpi: hotkey poll fixes
thinkpad-acpi: be more strict when detecting a ThinkPad
...
Many gpio chips allow to generate interrupts when the value of a pin
changes. This patch gives usermode application the opportunity to make
use of this feature by calling poll(2) on the /sys/class/gpio/gpioN/value
sysfs file. The edge to trigger can be set in the edge file in the same
directory. Possible values are "none", "rising", "falling", and "both".
Using level triggers is not possible with current sysfs since nothing
changes the GPIO value (and the IRQ keeps triggering). Edge triggering
will "just work". Note that if there was an event between read() and
poll(), the poll() returns immediately.
Also note that this version only supports true GPIO interrupts. Some
later patch might be able to synthesize this behavior by timer-driven
polling; some systems seem to need that.
[dbrownell@users.sourceforge.net: align ids to 16 bit ids; whitespace]
Signed-off-by: Daniel Glöckner <dg@emlix.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Some devices allow an individual function to be reset without affecting
other functions in the same device: that's what pci_reset_function does.
For devices that have this support, expose reset attribite in sysfs.
This is useful e.g. for virtualization, where a qemu userspace
process wants to reset the device when the guest is reset,
to emulate machine reboot as closely as possible.
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Also fix Documentation/led-class.txt, the acceptable
range of values for brightness is 0-max_brightness, not 0-255.
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Corentin Chary <corentincj@iksaif.net>
Signed-off-by: Len Brown <len.brown@intel.com>
Date and KernelVersion may be wrong because the lcd
interface was introduced before git initial import.
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Corentin Chary <corentincj@iksaif.net>
Signed-off-by: Len Brown <len.brown@intel.com>
Date and KernelVersion may be wrong because the backlight
interface was introduced before git initial import.
Cc:Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Corentin Chary <corentincj@iksaif.net>
Signed-off-by: Len Brown <len.brown@intel.com>
Update topology comments and sysfs documentation based upon discussions
with Neil Brown.
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* git://git.infradead.org/mtd-2.6: (63 commits)
mtd: OneNAND: Allow setting of boundary information when built as module
jffs2: leaking jffs2_summary in function jffs2_scan_medium
mtd: nand: Fix memory leak on txx9ndfmc probe failure.
mtd: orion_nand: use burst reads with double word accesses
mtd/nand: s3c6400 support for s3c2410 driver
[MTD] [NAND] S3C2410: Use DIV_ROUND_UP
[MTD] [NAND] S3C2410: Deal with unaligned lengths in S3C2440 buffer read/write
[MTD] [NAND] S3C2410: Allow the machine code to get the BBT table from NAND
[MTD] [NAND] S3C2410: Added a kerneldoc for s3c2410_nand_set
mtd: physmap_of: Add multiple regions and concatenation support
mtd: nand: max_retries off by one in mxc_nand
mtd: nand: s3c2410_nand_setrate(): use correct macros for 2412/2440
mtd: onenand: add bbt_wait & unlock_all as replaceable for some platform
mtd: Flex-OneNAND support
mtd: nand: add OMAP2/OMAP3 NAND driver
mtd: maps: Blackfin async: fix memory leaks in probe/remove funcs
mtd: uclinux: mark local stuff static
mtd: uclinux: do not allow to be built as a module
mtd: uclinux: allow systems to override map addr/size
mtd: blackfin NFC: fix hang when using NAND on BF527-EZKITs
...
* 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6: (74 commits)
PCI: make msi_free_irqs() to use msix_mask_irq() instead of open coded write
PCI: Fix the NIU MSI-X problem in a better way
PCI ASPM: remove get_root_port_link
PCI ASPM: cleanup pcie_aspm_sanity_check
PCI ASPM: remove has_switch field
PCI ASPM: cleanup calc_Lx_latency
PCI ASPM: cleanup pcie_aspm_get_cap_device
PCI ASPM: cleanup clkpm checks
PCI ASPM: cleanup __pcie_aspm_check_state_one
PCI ASPM: cleanup initialization
PCI ASPM: cleanup change input argument of aspm functions
PCI ASPM: cleanup misc in struct pcie_link_state
PCI ASPM: cleanup clkpm state in struct pcie_link_state
PCI ASPM: cleanup latency field in struct pcie_link_state
PCI ASPM: cleanup aspm state field in struct pcie_link_state
PCI ASPM: fix typo in struct pcie_link_state
PCI: drivers/pci/slot.c should depend on CONFIG_SYSFS
PCI: remove redundant __msi_set_enable()
PCI PM: consistently use type bool for wake enable variable
x86/ACPI: Correct maximum allowed _CRS returned resources and warn if exceeded
...
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
jbd2: clean up jbd2_journal_try_to_free_buffers()
ext4: Don't update ctime for non-extent-mapped inodes
ext4: Fix up whitespace issues in fs/ext4/inode.c
ext4: Fix 64-bit block type problem on 32-bit platforms
ext4: teach the inode allocator to use a goal inode number
ext4: Use a hash of the topdir directory name for the Orlov parent group
ext4: document the "abort" mount option
ext4: move the abort flag from s_mount_opts to s_mount_flags
ext4: update the s_last_mounted field in the superblock
ext4: change s_mount_opt to be an unsigned int
ext4: online defrag -- Add EXT4_IOC_MOVE_EXT ioctl
ext4: avoid unnecessary spinlock in critical POSIX ACL path
ext3: avoid unnecessary spinlock in critical POSIX ACL path
ext4: convert instrumentation from markers to tracepoints
jbd2: convert instrumentation from markers to tracepoints
This patch adds the kernel side of the PPS support currently named
"LinuxPPS".
PPS means "pulse per second" and a PPS source is just a device which
provides a high precision signal each second so that an application can
use it to adjust system clock time.
Common use is the combination of the NTPD as userland program with a GPS
receiver as PPS source to obtain a wallclock-time with sub-millisecond
synchronisation to UTC.
To obtain this goal the userland programs shoud use the PPS API
specification (RFC 2783 - Pulse-Per-Second API for UNIX-like Operating
Systems, Version 1.0) which in part is implemented by this patch. It
provides a set of chars devices, one per PPS source, which can be used to
get the time signal. The RFC's functions can be implemented by accessing
to these char devices.
Signed-off-by: Rodolfo Giometti <giometti@linux.it>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Greg KH <greg@kroah.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Michael Kerrisk <mtk.manpages@googlemail.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Create symbolic link to hotplug driver module in the PCI slot
directory (/sys/bus/pci/slots/<SLOT#>). In the past, we need to load
hotplug drivers one by one to identify the hotplug driver that handles
the slot, and it was very inconvenient especially for trouble shooting.
With this change, we can easily identify the hotplug driver.
Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Reviewed-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Enhance the inode allocator to take a goal inode number as a
paremeter; if it is specified, it takes precedence over Orlov or
parent directory inode allocation algorithms.
The extents migration function uses the goal inode number so that the
extent trees allocated the migration function use the correct flex_bg.
In the future, the goal inode functionality will also be used to
allocate an adjacent inode for the extended attributes.
Also, for testing purposes the goal inode number can be specified via
/sys/fs/{dev}/inode_goal. This can be useful for testing inode
allocation beyond 2^32 blocks on very large filesystems.
Signed-off-by: Andreas Dilger <adilger@sun.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
* 'for-2.6.31' of git://git.kernel.dk/linux-2.6-block: (153 commits)
block: add request clone interface (v2)
floppy: fix hibernation
ramdisk: remove long-deprecated "ramdisk=" boot-time parameter
fs/bio.c: add missing __user annotation
block: prevent possible io_context->refcount overflow
Add serial number support for virtio_blk, V4a
block: Add missing bounce_pfn stacking and fix comments
Revert "block: Fix bounce limit setting in DM"
cciss: decode unit attention in SCSI error handling code
cciss: Remove no longer needed sendcmd reject processing code
cciss: change SCSI error handling routines to work with interrupts enabled.
cciss: separate error processing and command retrying code in sendcmd_withirq_core()
cciss: factor out fix target status processing code from sendcmd functions
cciss: simplify interface of sendcmd() and sendcmd_withirq()
cciss: factor out core of sendcmd_withirq() for use by SCSI error handling code
cciss: Use schedule_timeout_uninterruptible in SCSI error handling code
block: needs to set the residual length of a bidi request
Revert "block: implement blkdev_readpages"
block: Fix bounce limit setting in DM
Removed reference to non-existing file Documentation/PCI/PCI-DMA-mapping.txt
...
Manually fix conflicts with tracing updates in:
block/blk-sysfs.c
drivers/ide/ide-atapi.c
drivers/ide/ide-cd.c
drivers/ide/ide-floppy.c
drivers/ide/ide-tape.c
include/trace/events/block.h
kernel/trace/blktrace.c
Add sysfs entries to the cciss driver needed for the dm/multipath tools.
A file for vendor, model, rev, and unique_id is added for each logical
drive under directory /sys/bus/pci/devices/<dev>/ccissX/cXdY. Where X =
the controller (or host) number and Y is the logical drive number.
A link from /sys/bus/pci/devices/<dev>/ccissX/cXdY/block:cciss!cXdY to
/sys/block/cciss!cXdY/device is also created. A bus is created in
/sys/bus/cciss. A link is created from the pci ccissX entry to
/sys/bus/cciss/devices/ccissX. Please consider this for inclusion.
Signed-off-by: Mike Miller <mike.miller@hp.com>
Cc: Stephen M. Cameron <scameron@beardog.cca.cpqcorp.net>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
To support devices with physical block sizes bigger than 512 bytes we
need to ensure proper alignment. This patch adds support for exposing
I/O topology characteristics as devices are stacked.
logical_block_size is the smallest unit the device can address.
physical_block_size indicates the smallest I/O the device can write
without incurring a read-modify-write penalty.
The io_min parameter is the smallest preferred I/O size reported by
the device. In many cases this is the same as the physical block
size. However, the io_min parameter can be scaled up when stacking
(RAID5 chunk size > physical block size).
The io_opt characteristic indicates the optimal I/O size reported by
the device. This is usually the stripe width for arrays.
The alignment_offset parameter indicates the number of bytes the start
of the device/partition is offset from the device's natural alignment.
Partition tools and MD/DM utilities can use this to pad their offsets
so filesystems start on proper boundaries.
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Adds documentation for the slub ABI.
This is placed in the `testing' directory since the meanings of these
files are still subject to change as slub is developed.
Acked-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>