This patch is preparation for replacing most uses of
".bss.page_aligned" and ".data.page_aligned" in the kernel with
macros, so that the section name can later be changed without having
to touch a lot of the kernel.
The long-term goal here is to be able to change the kernel's magic
section names to those that are compatible with -ffunction-sections
-fdata-sections. This requires renaming all magic sections with names
of the form ".data.foo".
Signed-off-by: Tim Abbott <tabbott@ksplice.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Currently the 4th parameter of get_user_pages() is called len, but its
in pages, not bytes. Rename the thing to nr_pages to avoid future
confusion.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* git://git.infradead.org/battery-2.6:
da9030_battery: Fix race between event handler and monitor
Add MAX17040 Fuel Gauge driver
w1: ds2760_battery: add support for sleep mode feature
w1: ds2760: add support for EEPROM read and write
ds2760_battery: cleanups in ds2760_battery_probe()
* git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-2.6-dm: (48 commits)
dm mpath: change to be request based
dm: disable interrupt when taking map_lock
dm: do not set QUEUE_ORDERED_DRAIN if request based
dm: enable request based option
dm: prepare for request based option
dm raid1: add userspace log
dm: calculate queue limits during resume not load
dm log: fix create_log_context to use logical_block_size of log device
dm target:s introduce iterate devices fn
dm table: establish queue limits by copying table limits
dm table: replace struct io_restrictions with struct queue_limits
dm table: validate device logical_block_size
dm table: ensure targets are aligned to logical_block_size
dm ioctl: support cookies for udev
dm: sysfs add suspended attribute
dm table: improve warning message when devices not freed before destruction
dm mpath: add service time load balancer
dm mpath: add queue length load balancer
dm mpath: add start_io and nr_bytes to path selectors
dm snapshot: use barrier when writing exception store
...
* 'audit.b63' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit-current:
Fix rule eviction order for AUDIT_DIR
Audit: clean up all op= output to include string quoting
Audit: move audit_get_nd completely into audit_watch
audit: seperate audit inode watches into a subfile
Audit: clean up audit_receive_skb
Audit: cleanup netlink mesg handling
Audit: unify the printk of an skb when auditd not around
Audit: dereferencing krule as if it were an audit_watch
Audit: better estimation of execve record length
Audit: fix audit watch use after free
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6: (72 commits)
asus-laptop: remove EXPERIMENTAL dependency
asus-laptop: use pr_fmt and pr_<level>
eeepc-laptop: cpufv updates
eeepc-laptop: sync eeepc-laptop with asus_acpi
asus_acpi: Deprecate in favor of asus-laptop
acpi4asus: update MAINTAINER and KConfig links
asus-laptop: platform dev as parent for led and backlight
eeepc-laptop: enable camera by default
ACPI: Rename ACPI processor device bus ID
acerhdf: Acer Aspire One fan control
ACPI: video: DMI workaround broken Acer 7720 BIOS enabling display brightness
ACPI: run ACPI device hot removal in kacpi_hotplug_wq
ACPI: Add the reference count to avoid unloading ACPI video bus twice
ACPI: DMI to disable Vista compatibility on some Sony laptops
ACPI: fix a deadlock in hotplug case
Show the physical device node of backlight class device.
ACPI: pdc init related memory leak with physical CPU hotplug
ACPI: pci_root: remove unused dev/fn information
ACPI: pci_root: simplify list traversals
ACPI: pci_root: use driver data rather than list lookup
...
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (23 commits)
switch xfs to generic acl caching helpers
helpers for acl caching + switch to those
switch shmem to inode->i_acl
switch reiserfs to inode->i_acl
switch reiserfs to usual conventions for caching ACLs
reiserfs: minimal fix for ACL caching
switch nilfs2 to inode->i_acl
switch btrfs to inode->i_acl
switch jffs2 to inode->i_acl
switch jfs to inode->i_acl
switch ext4 to inode->i_acl
switch ext3 to inode->i_acl
switch ext2 to inode->i_acl
add caching of ACLs in struct inode
fs: Add new pre-allocation ioctls to vfs for compatibility with legacy xfs ioctls
cleanup __writeback_single_inode
... and the same for vfsmount id/mount group id
Make allocation of anon devices cheaper
update Documentation/filesystems/Locking
devpts: remove module-related code
...
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6:
bnx2: Fix the behavior of ethtool when ONBOOT=no
qla3xxx: Don't sleep while holding lock.
qla3xxx: Give the PHY time to come out of reset.
ipv4 routing: Ensure that route cache entries are usable and reclaimable with caching is off
net: Move rx skb_orphan call to where needed
ipv6: Use correct data types for ICMPv6 type and code
net: let KS8842 driver depend on HAS_IOMEM
can: let SJA1000 driver depend on HAS_IOMEM
netxen: fix firmware init handshake
netxen: fix build with without CONFIG_PM
netfilter: xt_rateest: fix comparison with self
netfilter: xt_quota: fix incomplete initialization
netfilter: nf_log: fix direct userspace memory access in proc handler
netfilter: fix some sparse endianess warnings
netfilter: nf_conntrack: fix conntrack lookup race
netfilter: nf_conntrack: fix confirmation race condition
netfilter: nf_conntrack: death_by_timeout() fix
helpers: get_cached_acl(inode, type), set_cached_acl(inode, type, acl),
forget_cached_acl(inode, type).
ubifs/xattr.c needed includes reordered, the rest is a plain switchover.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This patch adds ioctls to vfs for compatibility with legacy XFS
pre-allocation ioctls (XFS_IOC_*RESVP*). The implementation
effectively invokes sys_fallocate for the new ioctls.
Also handles the compat_ioctl case.
Note: These legacy ioctls are also implemented by OCFS2.
[AV: folded fixes from hch]
Signed-off-by: Ankit Jain <me@ankitjain.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
There are some broken devices that report multiple DMA xfer modes
enabled at once (ATA spec doesn't allow it) but otherwise work fine
with DMA so just delete ide_id_dma_bug().
[ As discovered by detective work by Frans and Bart, due to how
handling of the ID block was handled before commit c419993
("ide-iops: only clear DMA words on setting DMA mode") this
check was always seeing zeros in the fields or other similar
garbage. Therefore this check wasn't actually checking anything.
Now that the tests actually check the real bits, all we see are
devices that trigger the check yet work perfectly fine, therefore
killing this useless check is the best thing to do. -DaveM ]
Reported-by: Frans Pop <elendil@planet.nl>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
A number of places in the audit system we send an op= followed by a string
that includes spaces. Somehow this works but it's just wrong. This patch
moves all of those that I could find to be quoted.
Example:
Change From: type=CONFIG_CHANGE msg=audit(1244666690.117:31): auid=0 ses=1
subj=unconfined_u:unconfined_r:auditctl_t:s0-s0:c0.c1023 op=remove rule
key="number2" list=4 res=0
Change To: type=CONFIG_CHANGE msg=audit(1244666690.117:31): auid=0 ses=1
subj=unconfined_u:unconfined_r:auditctl_t:s0-s0:c0.c1023 op="remove rule"
key="number2" list=4 res=0
Signed-off-by: Eric Paris <eparis@redhat.com>
* git://git.infradead.org/iommu-2.6:
Intel-IOMMU, intr-remap: source-id checking
Intel-IOMMU, intr-remap: set the whole 128bits of irte when modify/free it
IOMMU Identity Mapping Support (drivers/pci/intel_iommu.c)
* 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jlbec/ocfs2:
ocfs2/trivial: Wrap ocfs2_sysfile_cluster_lock_key within define.
ocfs2: Add lockdep annotations
vfs: Set special lockdep map for dirs only if not set by fs
ocfs2: Disable orphan scanning for local and hard-ro mounts
ocfs2: Do not initialize lvb in ocfs2_orphan_scan_lock_res_init()
ocfs2: Stop orphan scan as early as possible during umount
ocfs2: Fix ocfs2_osb_dump()
ocfs2: Pin journal head before accessing jh->b_committed_data
ocfs2: Update atime in splice read if necessary.
ocfs2: Provide the ocfs2_dlm_lvb_valid() stack API.
To support domain-isolation usages, the platform hardware must be
capable of uniquely identifying the requestor (source-id) for each
interrupt message. Without source-id checking for interrupt remapping
, a rouge guest/VM with assigned devices can launch interrupt attacks
to bring down anothe guest/VM or the VMM itself.
This patch adds source-id checking for interrupt remapping, and then
really isolates interrupts for guests/VMs with assigned devices.
Because PCI subsystem is not initialized yet when set up IOAPIC
entries, use read_pci_config_byte to access PCI config space directly.
Signed-off-by: Weidong Han <weidong.han@intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
After the recent changes that went into mm/vmscan.c to overhaul stuff, we
ended up with these warnings on no-mmu systems:
mm/vmscan.c: In function `shrink_page_list':
mm/vmscan.c:580: warning: unused variable `vm_flags'
mm/vmscan.c: In function `shrink_active_list':
mm/vmscan.c:1294: warning: `vm_flags' may be used uninitialized in this function
mm/vmscan.c:1242: note: `vm_flags' was declared here
This is because the no-mmu function defines page_referenced() to work on
the first argument only (the page). It does not clear the vm_flags given
to it because for no-mmu systems, they never actually get utilized. Since
that is no longer strictly true, we need to set vm_flags to 0 like
everyone else so gcc can do proper dead code elimination without annoying
us with unused warnings.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Cc: David Howells <dhowells@redhat.com>
Acked-by: David McCullough <davidm@snapgear.com>
Cc: Greg Ungerer <gerg@uclinux.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If a kthread happens to use get_user_pages() on an mm (as KSM does),
there's a chance that it will end up trying to read in a swap page, then
oops in grab_swap_token() because the kthread has no mm: GUP passes down
the right mm, so grab_swap_token() ought to be using it.
We have not identified a stronger case than KSM's daemon (not yet in
mainline), but the issue must have come up before, since RHEL has included
a fix for this for years (though a different fix, they just back out of
grab_swap_token if current->mm is unset: which is what we first proposed,
but using the right mm here seems more correct).
Reported-by: Izik Eidus <ieidus@redhat.com>
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
handle_mm_fault() is now passing fault flags rather than write_access
down to hugetlb_fault(), so better recognize that in hugetlb_fault(),
and in hugetlb_no_page().
Signed-off-by: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Acked-by: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Change all the code that deals directly with ICMPv6 type and code
values to use u8 instead of a signed int as that's the actual data
type.
Signed-off-by: Brian Haley <brian.haley@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
gspca_ov519: add support for the ov511 bridge
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
This patch adds autobrightness (so that it can
be turned off to make the already present brightness
control work) and light frequency filtering controls.
The lightfreq control needed 2 different entries
in the ctrls array, as the number of options differs
depending on the sensor. Always one of the 2 entires is
disabled ofcourse.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
* git://git.infradead.org/~dwmw2/iommu-2.6.31:
intel-iommu: Fix one last ia64 build problem in Pass Through Support
VT-d: support the device IOTLB
VT-d: cleanup iommu_flush_iotlb_psi and flush_unmaps
VT-d: add device IOTLB invalidation support
VT-d: parse ATSR in DMA Remapping Reporting Structure
PCI: handle Virtual Function ATS enabling
PCI: support the ATS capability
intel-iommu: dmar_set_interrupt return error value
intel-iommu: Tidy up iommu->gcmd handling
intel-iommu: Fix tiny theoretical race in write-buffer flush.
intel-iommu: Clean up handling of "caching mode" vs. IOTLB flushing.
intel-iommu: Clean up handling of "caching mode" vs. context flushing.
VT-d: fix invalid domain id for KVM context flush
Fix !CONFIG_DMAR build failure introduced by Intel IOMMU Pass Through Support
Intel IOMMU Pass Through Support
Fix up trivial conflicts in drivers/pci/{intel-iommu.c,intr_remapping.c}
The purpose of this patch is to improve the remote mount path lookup
support for distributed filesystems such as the NFSv4 client.
When given a mount command of the form "mount server:/foo/bar /mnt", the
NFSv4 client is required to look up the filehandle for "server:/", and
then look up each component of the remote mount path "foo/bar" in order
to find the directory that is actually going to be mounted on /mnt.
Following that remote mount path may involve following symlinks,
crossing server-side mount points and even following referrals to
filesystem volumes on other servers.
Since the standard VFS path lookup code already supports walking paths
that contain all these features (using in-kernel automounts for
following referrals) we would like to be able to reuse that rather than
duplicate the full path traversal functionality in the NFSv4 client code.
This patch therefore defines a VFS helper function create_mnt_ns(), that
sets up a temporary filesystem namespace and attaches a root filesystem to
it. It exports the create_mnt_ns() and put_mnt_ns() function for use by
filesystem modules.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In order to allow modules to use it without having to export vfsmount_lock.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
SLAB uses get/put_online_cpus() which use a mutex which is itself only
initialized when cpu_hotplug_init() is called. Currently we hang suring
boot in SLAB due to doing that too late.
Reported by James Bottomley and Sachin Sant (and possibly others).
Debugged by Benjamin Herrenschmidt.
This just removes the dynamic initialization of the data structures, and
replaces it with a static one, avoiding this dependency entirely, and
removing one unnecessary special initcall.
Tested-by: Sachin Sant <sachinp@in.ibm.com>
Tested-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Tested-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 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
...
Some filesystems need to set lockdep map for i_mutex differently for
different directories. For example OCFS2 has system directories (for
orphan inode tracking and for gathering all system files like journal
or quota files into a single place) which have different locking
locking rules than standard directories. For a filesystem setting
lockdep map is naturaly done when the inode is read but we have to
modify unlock_new_inode() not to overwrite the lockdep map the filesystem
has set.
Acked-by: peterz@infradead.org
CC: mingo@redhat.com
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
* 'for-2.6.31' of git://fieldses.org/git/linux-nfsd: (60 commits)
SUNRPC: Fix the TCP server's send buffer accounting
nfsd41: Backchannel: minorversion support for the back channel
nfsd41: Backchannel: cleanup nfs4.0 callback encode routines
nfsd41: Remove ip address collision detection case
nfsd: optimise the starting of zero threads when none are running.
nfsd: don't take nfsd_mutex twice when setting number of threads.
nfsd41: sanity check client drc maxreqs
nfsd41: move channel attributes from nfsd4_session to a nfsd4_channel_attr struct
NFS: kill off complicated macro 'PROC'
sunrpc: potential memory leak in function rdma_read_xdr
nfsd: minor nfsd_vfs_write cleanup
nfsd: Pull write-gathering code out of nfsd_vfs_write
nfsd: track last inode only in use_wgather case
sunrpc: align cache_clean work's timer
nfsd: Use write gathering only with NFSv2
NFSv4: kill off complicated macro 'PROC'
NFSv4: do exact check about attribute specified
knfsd: remove unreported filehandle stats counters
knfsd: fix reply cache memory corruption
knfsd: reply cache cleanups
...
* 'for-2.6.31' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6: (128 commits)
nfs41: sunrpc: xprt_alloc_bc_request() should not use spin_lock_bh()
nfs41: Move initialization of nfs4_opendata seq_res to nfs4_init_opendata_res
nfs: remove unnecessary NFS_INO_INVALID_ACL checks
NFS: More "sloppy" parsing problems
NFS: Invalid mount option values should always fail, even with "sloppy"
NFS: Remove unused XDR decoder functions
NFS: Update MNT and MNT3 reply decoding functions
NFS: add XDR decoder for mountd version 3 auth-flavor lists
NFS: add new file handle decoders to in-kernel mountd client
NFS: Add separate mountd status code decoders for each mountd version
NFS: remove unused function in fs/nfs/mount_clnt.c
NFS: Use xdr_stream-based XDR encoder for MNT's dirpath argument
NFS: Clean up MNT program definitions
lockd: Don't bother with RPC ping for NSM upcalls
lockd: Update NSM state from SM_MON replies
NFS: Fix false error return from nfs_callback_up() if ipv6.ko is not available
NFS: Return error code from nfs_callback_up() to user space
NFS: Do not display the setting of the "intr" mount option
NFS: add support for splice writes
nfs41: Backchannel: CB_SEQUENCE validation
...
* '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
...
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6: (43 commits)
via-velocity: Fix velocity driver unmapping incorrect size.
mlx4_en: Remove redundant refill code on RX
mlx4_en: Removed redundant check on lso header size
mlx4_en: Cancel port_up check in transmit function
mlx4_en: using stop/start_all_queues
mlx4_en: Removed redundant skb->len check
mlx4_en: Counting all the dropped packets on the TX side
usbnet cdc_subset: fix issues talking to PXA gadgets
Net: qla3xxx, remove sleeping in atomic
ipv4: fix NULL pointer + success return in route lookup path
isdn: clean up documentation index
cfg80211: validate station settings
cfg80211: allow setting station parameters in mesh
cfg80211: allow adding/deleting stations on mesh
ath5k: fix beacon_int handling
MAINTAINERS: Fix Atheros pattern paths
ath9k: restore PS mode, before we put the chip into FULL SLEEP state.
ath9k: wait for beacon frame along with CAB
acer-wmi: fix rfkill conversion
ath5k: avoid PCI FATAL interrupts by restoring RETRY_TIMEOUT disabling
...
Add the wakeup enable register to the list of OMAP-specific UART
registers. This is to support forthcoming OMAP PM enhancements which
use the wakeup feature of the OMAP's 8250-based UART.
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch adds core functions for request-based dm.
When struct mapped device (md) is initialized, md->queue has
an I/O scheduler and the following functions are used for
request-based dm as the queue functions:
make_request_fn: dm_make_request()
pref_fn: dm_prep_fn()
request_fn: dm_request_fn()
softirq_done_fn: dm_softirq_done()
lld_busy_fn: dm_lld_busy()
Actual initializations are done in another patch (PATCH 2).
Below is a brief summary of how request-based dm behaves, including:
- making request from bio
- cloning, mapping and dispatching request
- completing request and bio
- suspending md
- resuming md
bio to request
==============
md->queue->make_request_fn() (dm_make_request()) calls __make_request()
for a bio submitted to the md.
Then, the bio is kept in the queue as a new request or merged into
another request in the queue if possible.
Cloning and Mapping
===================
Cloning and mapping are done in md->queue->request_fn() (dm_request_fn()),
when requests are dispatched after they are sorted by the I/O scheduler.
dm_request_fn() checks busy state of underlying devices using
target's busy() function and stops dispatching requests to keep them
on the dm device's queue if busy.
It helps better I/O merging, since no merge is done for a request
once it is dispatched to underlying devices.
Actual cloning and mapping are done in dm_prep_fn() and map_request()
called from dm_request_fn().
dm_prep_fn() clones not only request but also bios of the request
so that dm can hold bio completion in error cases and prevent
the bio submitter from noticing the error.
(See the "Completion" section below for details.)
After the cloning, the clone is mapped by target's map_rq() function
and inserted to underlying device's queue using
blk_insert_cloned_request().
Completion
==========
Request completion can be hooked by rq->end_io(), but then, all bios
in the request will have been completed even error cases, and the bio
submitter will have noticed the error.
To prevent the bio completion in error cases, request-based dm clones
both bio and request and hooks both bio->bi_end_io() and rq->end_io():
bio->bi_end_io(): end_clone_bio()
rq->end_io(): end_clone_request()
Summary of the request completion flow is below:
blk_end_request() for a clone request
=> blk_update_request()
=> bio->bi_end_io() == end_clone_bio() for each clone bio
=> Free the clone bio
=> Success: Complete the original bio (blk_update_request())
Error: Don't complete the original bio
=> blk_finish_request()
=> rq->end_io() == end_clone_request()
=> blk_complete_request()
=> dm_softirq_done()
=> Free the clone request
=> Success: Complete the original request (blk_end_request())
Error: Requeue the original request
end_clone_bio() completes the original request on the size of
the original bio in successful cases.
Even if all bios in the original request are completed by that
completion, the original request must not be completed yet to keep
the ordering of request completion for the stacking.
So end_clone_bio() uses blk_update_request() instead of
blk_end_request().
In error cases, end_clone_bio() doesn't complete the original bio.
It just frees the cloned bio and gives over the error handling to
end_clone_request().
end_clone_request(), which is called with queue lock held, completes
the clone request and the original request in a softirq context
(dm_softirq_done()), which has no queue lock, to avoid a deadlock
issue on submission of another request during the completion:
- The submitted request may be mapped to the same device
- Request submission requires queue lock, but the queue lock
has been held by itself and it doesn't know that
The clone request has no clone bio when dm_softirq_done() is called.
So target drivers can't resubmit it again even error cases.
Instead, they can ask dm core for requeueing and remapping
the original request in that cases.
suspend
=======
Request-based dm uses stopping md->queue as suspend of the md.
For noflush suspend, just stops md->queue.
For flush suspend, inserts a marker request to the tail of md->queue.
And dispatches all requests in md->queue until the marker comes to
the front of md->queue. Then, stops dispatching request and waits
for the all dispatched requests to complete.
After that, completes the marker request, stops md->queue and
wake up the waiter on the suspend queue, md->wait.
resume
======
Starts md->queue.
Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
This patch contains a device-mapper mirror log module that forwards
requests to userspace for processing.
The structures used for communication between kernel and userspace are
located in include/linux/dm-log-userspace.h. Due to the frequency,
diversity, and 2-way communication nature of the exchanges between
kernel and userspace, 'connector' was chosen as the interface for
communication.
The first log implementations written in userspace - "clustered-disk"
and "clustered-core" - support clustered shared storage. A userspace
daemon (in the LVM2 source code repository) uses openAIS/corosync to
process requests in an ordered fashion with the rest of the nodes in the
cluster so as to prevent log state corruption. Other implementations
with no association to LVM or openAIS/corosync, are certainly possible.
(Imagine if two machines are writing to the same region of a mirror.
They would both mark the region dirty, but you need a cluster-aware
entity that can handle properly marking the region clean when they are
done. Otherwise, you might clear the region when the first machine is
done, not the second.)
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Cc: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Currently, device-mapper maintains a separate instance of 'struct
queue_limits' for each table of each device. When the configuration of
a device is to be changed, first its table is loaded and this structure
is populated, then the device is 'resumed' and the calculated
queue_limits are applied.
This places restrictions on how userspace may process related devices,
where it is often advantageous to 'load' tables for several devices
at once before 'resuming' them together. As the new queue_limits
only take effect after the 'resume', if they are changing and one
device uses another, the latter must be 'resumed' before the former
may be 'loaded'.
This patch moves the calculation of these queue_limits out of
the 'load' operation into 'resume'. Since we are no longer
pre-calculating this struct, we no longer need to maintain copies
within our dm structs.
dm_set_device_limits() now passes the 'start' of the device's
data area (aka pe_start) as the 'offset' to blk_stack_limits().
init_valid_queue_limits() is replaced by blk_set_default_limits().
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: martin.petersen@oracle.com
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Add .iterate_devices to 'struct target_type' to allow a function to be
called for all devices in a DM target. Implemented it for all targets
except those in dm-snap.c (origin and snapshot).
(The raid1 version number jumps to 1.12 because we originally reserved
1.1 to 1.11 for 'block_on_error' but ended up using 'handle_errors'
instead.)
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Cc: martin.petersen@oracle.com
Use blk_stack_limits() to stack block limits (including topology) rather
than duplicate the equivalent within Device Mapper.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Add support for passing a 32 bit "cookie" into the kernel with the
DM_SUSPEND, DM_DEV_RENAME and DM_DEV_REMOVE ioctls. The (unsigned)
value of this cookie is returned to userspace alongside the uevents
issued by these ioctls in the variable DM_COOKIE.
This means the userspace process issuing these ioctls can be notified
by udev after udev has completed any actions triggered.
To minimise the interface extension, we pass the cookie into the
kernel in the event_nr field which is otherwise unused when calling
these ioctls. Incrementing the version number allows userspace to
determine in advance whether or not the kernel supports the cookie.
If the kernel does support this but userspace does not, there should
be no impact as the new variable will just get ignored.
Signed-off-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Introduce num_flush_requests for a target to set to say how many flush
instructions (empty barriers) it wants to receive. These are sent by
__clone_and_map_empty_barrier with map_info->flush_request going from 0
to (num_flush_requests - 1).
Old targets without flush support won't receive any flush requests.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Tim Abbott
Linus Torvalds
Peter Zijlstra
Al Viro
Markus Trippelsdorf
Ankit Jain
Bartlomiej Zolnierkiewicz
Len Brown
Eric Paris
Weidong Han
Mike Frysinger
Hugh Dickins
Brian Haley
Hans de Goede
Trond Myklebust
Jan Kara
Robert Love
Kevin Hilman
Kiyoshi Ueda
Jonthan Brassow
Mike Snitzer
Milan Broz
Mikulas Patocka