On an SMP system the kgdb_single_step flag has the possibility to
indefinitely hang the system in the case.  Consider the case where,
CPU 1 has the schedule lock and CPU 0 is set to single step, there is
no way for CPU 0 to run another task.

The easy way to observe the problem is to make 2 cpus busy, and run
the kgdb test suite.  You will see that it hangs the system very
quickly.

while [ 1 ] ; do find /proc > /dev/null 2>&1 ; done &
while [ 1 ] ; do find /proc > /dev/null 2>&1 ; done &
echo V1 > /sys/module/kgdbts/parameters/kgdbts

The side effect of this patch is that there is the possibility
to miss a breakpoint in the case that a single step operation
was executed to step over a breakpoint in common code.

The trade off of the missed breakpoint is preferred to
hanging the kernel.  This can be fixed in the future by
using kprobes or another strategy to step over planted
breakpoints with out of line execution.

CC: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>

The kgdb core should not assume that a single step operation of a
kernel thread will complete on the same CPU.  The single step flag is
set at the "thread" level and it is possible in a multi cpu system
that a kernel thread can get scheduled on another cpu the next time it
is run.

As a further safety net in case a slave cpu is hung, the debug master
cpu will try 100 times before giving up and assuming control of the
slave cpus is no longer possible.  It is more useful to be able to get
some information out of kgdb instead of spinning forever.
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>

It is possible for the user_mode_vm(regs) check to return true on the
i368 arch for a non master kgdb cpu or when the master kgdb cpu
handles the NMI watch dog exception.

The solution is simply to select the correct gdb_ss location
based on the check to user_mode_vm(regs).

CC: Ingo Molnar <mingo@elte.hu>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>

Some versions of gcc replace calls to strstr() with single-character
"needle" string parameters by calls to strchr() behind our back.
This causes linking errors if strchr() is defined as an inline function
in <asm/string.h> (e.g. on m68k, which BTW doesn't have kgdb support).

Prevent this by explicitly calling strchr() instead.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>

Prevent write to put_buf[BUFMAX] in kgdb test suite.

If put_buf_cnt was BUFMAX - 1 at the earlier test,
`\0' is written to put_buf[BUFMAX].
Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>

Roel Kluin reported an error found with Parfait.  Where we want to
ensure that that kgdb_info[-1] never gets accessed.

Also check to ensure any negative tid does not exceed the size of the
shadow CPU array, else report critical debug context because it is an
internal kgdb failure.
Reported-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>

The for loop starts with a breakno of 0, and ends when it's 4. so
this test is always true.
Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>

* 'drm-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6: (189 commits)
  drm/radeon/kms: fix warning about cur_placement being uninitialised.
  drm/ttm: Print debug information on memory manager when eviction fails
  drm: Add memory manager debug function
  drm/radeon/kms: restore surface registers on resume.
  drm/radeon/kms/r600/r700: fallback gracefully on ucode failure
  drm/ttm: Initialize eviction placement in case the driver callback doesn't
  drm/radeon/kms: cleanup structure and module if initialization fails
  drm/radeon/kms: actualy set the eviction placements we choose
  drm/radeon/kms: Fix NULL ptr dereference
  drm/radeon/kms/avivo: add support for new pll selection algo
  drm/radeon/kms/avivo: fix some bugs in the display bandwidth setup
  drm/radeon/kms: fix return value from fence function.
  drm/radeon: Remove tests for -ERESTART from the TTM code.
  drm/ttm: Have the TTM code return -ERESTARTSYS instead of -ERESTART.
  drm/radeon/kms: Convert radeon to new TTM validation API (V2)
  drm/ttm: Rework validation & memory space allocation (V3)
  drm: Add search/get functions to get a block in a specific range
  drm/radeon/kms: fix avivo tiling regression since radeon object rework
  drm/i915: Remove a debugging printk from hangcheck
  drm/radeon/kms: make sure i2c id matches
  ...

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/bp/bp: (21 commits)
  amd64_edac: bump driver version
  amd64_edac: fix use-uninitialised bug
  amd64_edac: correct sys address to chip select mapping
  amd64_edac: add a leaner syndrome decoding algorithm
  amd64_edac: remove early hw support check
  amd64_edac: detect DDR3 memory type
  edac: add memory types strings for debugging
  edac, mce: update AMD F10h revD check
  amd64_edac: remove unneeded extract_error_address wrapper
  amd64_edac: rename StinkyIdentifier
  amd64_edac: remove superfluous dbg printk
  amd64_edac: enhance address to DRAM bank mapping
  amd64_edac: cleanup f10_early_channel_count
  amd64_edac: dump DIMM sizes on K8 too
  amd64_edac: cleanup rest of amd64_dump_misc_regs
  amd64_edac: cleanup DRAM cfg low debug output
  amd64_edac: wrap-up pci config read error handling
  amd64_edac: unify MCGCTL ECC switching
  cpumask: use modern cpumask style in drivers/edac/amd64_edac.c
  amd64_edac: make DRAM regions output more human-readable
  ...

* 'for-linus' of git://gitorious.org/linux-omap-dss2/linux:
  MAINTAINERS: Add OMAP2/3 DSS and OMAPFB maintainer
  OMAP: SDP: Enable DSS2 for OMAP3 SDP board
  OMAP: DSS2: Taal DSI command mode panel driver
  OMAP: DSS2: Add generic and Sharp panel drivers
  OMAP: DSS2: omapfb driver
  OMAP: DSS2: DSI driver
  OMAP: DSS2: SDI driver
  OMAP: DSS2: RFBI driver
  OMAP: DSS2: Video encoder driver
  OMAP: DSS2: DPI driver
  OMAP: DSS2: DISPC
  OMAP: DSS2: Add more core files
  OMAP: DSS2: Display Subsystem Driver core
  OMAP: DSS2: Documentation for DSS2
  OMAP: Add support for VRFB rotation engine
  OMAP: Add VRAM manager
  OMAP: OMAPFB: add omapdss device
  OMAP: OMAPFB: split omapfb.h
  OMAP2: Add funcs for writing SMS_ROT_* registers

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  workqueue: Add debugobjects support

* 'bugfix' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen:
  xen: try harder to balloon up under memory pressure.
  Xen balloon: fix totalram_pages counting.
  xen: explicitly create/destroy stop_machine workqueues outside suspend/resume region.
  xen: improve error handling in do_suspend.
  xen: don't leak IRQs over suspend/resume.
  xen: call clock resume notifier on all CPUs
  xen: use iret for return from 64b kernel to 32b usermode
  xen: don't call dpm_resume_noirq() with interrupts disabled.
  xen: register runstate info for boot CPU early
  xen: register runstate on secondary CPUs
  xen: register timer interrupt with IRQF_TIMER
  xen: correctly restore pfn_to_mfn_list_list after resume
  xen: restore runstate_info even if !have_vcpu_info_placement
  xen: re-register runstate area earlier on resume.
  xen: wait up to 5 minutes for device connetion
  xen: improvement to wait_for_devices()
  xen: fix is_disconnected_device/exists_disconnected_device
  xen/xenbus: make DEVICE_ATTR()s static

* 'xen/fbdev' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen:
  xen pvfb: Inhibit VM_IO flag to be set on vmalloc-ed framebuffers.
  fb-defio: Inhibit VM_IO flag to be set on vmalloc-ed framebuffers.
  fb-defio: If FBINFO_VIRTFB is defined, do not set VM_IO flag.
  Fix toogle whether xenbus driver should be built as module or part of kernel.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/teigland/dlm:
  dlm: always use GFP_NOFS

* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (47 commits)
  ext4: Fix potential fiemap deadlock (mmap_sem vs. i_data_sem)
  ext4: Do not override ext2 or ext3 if built they are built as modules
  jbd2: Export jbd2_log_start_commit to fix ext4 build
  ext4: Fix insufficient checks in EXT4_IOC_MOVE_EXT
  ext4: Wait for proper transaction commit on fsync
  ext4: fix incorrect block reservation on quota transfer.
  ext4: quota macros cleanup
  ext4: ext4_get_reserved_space() must return bytes instead of blocks
  ext4: remove blocks from inode prealloc list on failure
  ext4: wait for log to commit when umounting
  ext4: Avoid data / filesystem corruption when write fails to copy data
  ext4: Use ext4 file system driver for ext2/ext3 file system mounts
  ext4: Return the PTR_ERR of the correct pointer in setup_new_group_blocks()
  jbd2: Add ENOMEM checking in and for jbd2_journal_write_metadata_buffer()
  ext4: remove unused parameter wbc from __ext4_journalled_writepage()
  ext4: remove encountered_congestion trace
  ext4: move_extent_per_page() cleanup
  ext4: initialize moved_len before calling ext4_move_extents()
  ext4: Fix double-free of blocks with EXT4_IOC_MOVE_EXT
  ext4: use ext4_data_block_valid() in ext4_free_blocks()
  ...

* 'for-linus' of git://git.open-osd.org/linux-open-osd:
  exofs: Multi-device mirror support
  exofs: Move all operations to an io_engine
  exofs: move osd.c to ios.c
  exofs: statfs blocks is sectors not FS blocks
  exofs: Prints on mount and unmout
  exofs: refactor exofs_i_info initialization into common helper
  exofs: dbg-print less
  exofs: More sane debug print
  trivial: some small fixes in exofs documentation

* git://git.infradead.org/ubifs-2.6:
  UBIFS: fix return code in check_leaf
  UBI: flush wl before clearing update marker
  MAINTAINERS: change e-mail of Artem Bityutskiy
  UBIFS: remove manual O_SYNC handling
  UBIFS: support mounting of UBI volume character devices
  UBI: Add ubi_open_volume_path

This patch drops usage of floating point variable for 32bit build
Signed-off-by: David T. L. Wong <davidtlwong@gmail.com>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

This patch changes on-disk format, it is accompanied with a parallel
patch to mkfs.exofs that enables multi-device capabilities.

After this patch, old exofs will refuse to mount a new formatted FS and
new exofs will refuse an old format. This is done by moving the magic
field offset inside the FSCB. A new FSCB *version* field was added. In
the future, exofs will refuse to mount unmatched FSCB version. To
up-grade or down-grade an exofs one must use mkfs.exofs --upgrade option
before mounting.

Introduced, a new object that contains a *device-table*. This object
contains the default *data-map* and a linear array of devices
information, which identifies the devices used in the filesystem. This
object is only written to offline by mkfs.exofs. This is why it is kept
separate from the FSCB, since the later is written to while mounted.

Same partition number, same object number is used on all devices only
the device varies.

* define the new format, then load the device table on mount time make
  sure every thing is supported.

* Change I/O engine to now support Mirror IO, .i.e write same data
  to multiple devices, read from a random device to spread the
  read-load from multiple clients (TODO: stripe read)

Implementation notes:
 A few points introduced in previous patch should be mentioned here:

* Special care was made so absolutlly all operation that have any chance
  of failing are done before any osd-request is executed. This is to
  minimize the need for a data consistency recovery, to only real IO
  errors.

* Each IO state has a kref. It starts at 1, any osd-request executed
  will increment the kref, finally when all are executed the first ref
  is dropped. At IO-done, each request completion decrements the kref,
  the last one to return executes the internal _last_io() routine.
  _last_io() will call the registered io_state_done. On sync mode a
  caller does not supply a done method, indicating a synchronous
  request, the caller is put to sleep and a special io_state_done is
  registered that will awaken the caller. Though also in sync mode all
  operations are executed in parallel.
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>

In anticipation for multi-device operations, we separate osd operations
into an abstract I/O API. Currently only one device is used but later
when adding more devices, we will drive all devices in parallel according
to a "data_map" that describes how data is arranged on multiple devices.
The file system level operates, like before, as if there is one object
(inode-number) and an i_size. The io engine will split this to the same
object-number but on multiple device.

At first we introduce Mirror (raid 1) layout. But at the final outcome
we intend to fully implement the pNFS-Objects data-map, including
raid 0,4,5,6 over mirrored devices, over multiple device-groups. And
more. See: http://tools.ietf.org/html/draft-ietf-nfsv4-pnfs-obj-12

* Define an io_state based API for accessing osd storage devices
  in an abstract way.
  Usage:
	First a caller allocates an io state with:
		exofs_get_io_state(struct exofs_sb_info *sbi,
				   struct exofs_io_state** ios);

	Then calles one of:
		exofs_sbi_create(struct exofs_io_state *ios);
		exofs_sbi_remove(struct exofs_io_state *ios);
		exofs_sbi_write(struct exofs_io_state *ios);
		exofs_sbi_read(struct exofs_io_state *ios);
		exofs_oi_truncate(struct exofs_i_info *oi, u64 new_len);

	And when done
		exofs_put_io_state(struct exofs_io_state *ios);

* Convert all source files to use this new API
* Convert from bio_alloc to bio_kmalloc
* In io engine we make use of the now fixed osd_req_decode_sense

There are no functional changes or on disk additions after this patch.
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>

If I do a "git mv" together with a massive code change
and commit in one patch, git looses the rename and
records a delete/new instead. This is bad because I want
a rename recorded so later rebased/cherry-picked patches
to the old name will work. Also the --follow is lost.
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>

Even though exofs has a 4k block size, statfs blocks
is in sectors (512 bytes).

Also if target returns 0 for capacity then make it
ULLONG_MAX. df does not like zero-size filesystems
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>

It is important to print in the logs when a filesystem was
mounted and eventually unmounted.

Print the osd-device's osd_name and pid the FS was
mounted/unmounted on.

TODO: How to also print the namespace path the filesystem was
      mounted on?
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>

There are two places that initialize inodes: exofs_iget() and
exofs_new_inode()

As more members of exofs_i_info that need initialization are
added this code will grow. (soon)
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>

Iner-loops printing is converted to EXOFS_DBG2 which is #defined
to nothing.

It is now almost bareable to just leave debug-on. Every operation
is printed once, with most relevant info (I hope).
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>

debug prints should be somewhat useful without actually
reading the source code
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>

Add exofs.txt to filesystems Documentation index and fix some typos,
identation and grammar.
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>

Signed-off-by: Dave Airlie <airlied@redhat.com>

This merges some TTM overhauls to allow us to do better object placement
for certain radeon GPUs that need scanout+cursor within range of each other,
along with an API change to not return ERESTART to userspace, but to use
ERESTARTSYS properly internally and have it convert to EINTR and catch that
correctly. Also lots of radeon fixes across the board.

Pull more Intel changes in, especially one to init the GTT properly

This add helper function to print information on eviction placements
and memory manager status when eviction fails to allocate memory
space.
Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

drm_mm_debug_table will print the memory manager state
in table allowing to give a snapshot of the manager at
given point in time. Usefull for debugging.
Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

On resume on my rv530 laptop surface cntl was left disabled, so
wierd stuff would happen with rendering to a tiled front buffer.

This checks if the surface regs are assigned to bos and reprograms
the surface registers on resume using the same path that clears
them all on init.
Signed-off-by: Dave Airlie <airlied@redhat.com>

Sent the wrong patch earlier.
Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

This would allow to catch driver callback error of not properly
setting the eviction placement structure.
Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@linux.ie>

This would allow us to properly unload others module like TTM if
initialization fails after we initiliazed TTM structure.
Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@linux.ie>

Stupid bug, somehow copying the eviction placements into the
result structure was missing.
Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@linux.ie>

radeon_atombios_fini might be call while there is not valid
atombios structure allocated, thus test for a not null ptr
before trying to access this structure.
Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@linux.ie>

Supported on all AVIVO-based asics.
Can be disabled via the new_pll module parameter:
new_pll=0 - disable
new_pll=1 - enable
enabled by default

[airlied: fixed to use do_div]
Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Dave Airlie <airlied@linux.ie>

Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Dave Airlie <airlied@linux.ie>