Merge 3.20 NVMe changes from Keith.

When reading blkio.throttle.io_serviced in a recently created blkio
cgroup, it's possible to race against the creation of a throttle policy,
which delays the allocation of stats_cpu.

Like other functions in the throttle code, just checking for a NULL
stats_cpu prevents the following oops caused by that race.

[ 1117.285199] Unable to handle kernel paging request for data at address 0x7fb4d0020
[ 1117.285252] Faulting instruction address: 0xc0000000003efa2c
[ 1137.733921] Oops: Kernel access of bad area, sig: 11 [#1]
[ 1137.733945] SMP NR_CPUS=2048 NUMA PowerNV
[ 1137.734025] Modules linked in: bridge stp llc kvm_hv kvm binfmt_misc autofs4
[ 1137.734102] CPU: 3 PID: 5302 Comm: blkcgroup Not tainted 3.19.0 #5
[ 1137.734132] task: c000000f1d188b00 ti: c000000f1d210000 task.ti: c000000f1d210000
[ 1137.734167] NIP: c0000000003efa2c LR: c0000000003ef9f0 CTR: c0000000003ef980
[ 1137.734202] REGS: c000000f1d213500 TRAP: 0300   Not tainted  (3.19.0)
[ 1137.734230] MSR: 9000000000009032 <SF,HV,EE,ME,IR,DR,RI>  CR: 42008884  XER: 20000000
[ 1137.734325] CFAR: 0000000000008458 DAR: 00000007fb4d0020 DSISR: 40000000 SOFTE: 0
GPR00: c0000000003ed3a0 c000000f1d213780 c000000000c59538 0000000000000000
GPR04: 0000000000000800 0000000000000000 0000000000000000 0000000000000000
GPR08: ffffffffffffffff 00000007fb4d0020 00000007fb4d0000 c000000000780808
GPR12: 0000000022000888 c00000000fdc0d80 0000000000000000 0000000000000000
GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
GPR20: 000001003e120200 c000000f1d5b0cc0 0000000000000200 0000000000000000
GPR24: 0000000000000001 c000000000c269e0 0000000000000020 c000000f1d5b0c80
GPR28: c000000000ca3a08 c000000000ca3dec c000000f1c667e00 c000000f1d213850
[ 1137.734886] NIP [c0000000003efa2c] .tg_prfill_cpu_rwstat+0xac/0x180
[ 1137.734915] LR [c0000000003ef9f0] .tg_prfill_cpu_rwstat+0x70/0x180
[ 1137.734943] Call Trace:
[ 1137.734952] [c000000f1d213780] [d000000005560520] 0xd000000005560520 (unreliable)
[ 1137.734996] [c000000f1d2138a0] [c0000000003ed3a0] .blkcg_print_blkgs+0xe0/0x1a0
[ 1137.735039] [c000000f1d213960] [c0000000003efb50] .tg_print_cpu_rwstat+0x50/0x70
[ 1137.735082] [c000000f1d2139e0] [c000000000104b48] .cgroup_seqfile_show+0x58/0x150
[ 1137.735125] [c000000f1d213a70] [c0000000002749dc] .kernfs_seq_show+0x3c/0x50
[ 1137.735161] [c000000f1d213ae0] [c000000000218630] .seq_read+0xe0/0x510
[ 1137.735197] [c000000f1d213bd0] [c000000000275b04] .kernfs_fop_read+0x164/0x200
[ 1137.735240] [c000000f1d213c80] [c0000000001eb8e0] .__vfs_read+0x30/0x80
[ 1137.735276] [c000000f1d213cf0] [c0000000001eb9c4] .vfs_read+0x94/0x1b0
[ 1137.735312] [c000000f1d213d90] [c0000000001ebb38] .SyS_read+0x58/0x100
[ 1137.735349] [c000000f1d213e30] [c000000000009218] syscall_exit+0x0/0x98
[ 1137.735383] Instruction dump:
[ 1137.735405] 7c6307b4 7f891800 409d00b8 60000000 60420000 3d420004 392a63b0 786a1f24
[ 1137.735471] 7d49502a e93e01c8 7d495214 7d2ad214 <7cead02a> e9090008 e9490010 e9290018

And here is one code that allows to easily reproduce this, although this
has first been found by running docker.

void run(pid_t pid)
{
	int n;
	int status;
	int fd;
	char *buffer;
	buffer = memalign(BUFFER_ALIGN, BUFFER_SIZE);
	n = snprintf(buffer, BUFFER_SIZE, "%d\n", pid);
	fd = open(CGPATH "/test/tasks", O_WRONLY);
	write(fd, buffer, n);
	close(fd);
	if (fork() > 0) {
		fd = open("/dev/sda", O_RDONLY | O_DIRECT);
		read(fd, buffer, 512);
		close(fd);
		wait(&status);
	} else {
		fd = open(CGPATH "/test/blkio.throttle.io_serviced", O_RDONLY);
		n = read(fd, buffer, BUFFER_SIZE);
		close(fd);
	}
	free(buffer);
	exit(0);
}

void test(void)
{
	int status;
	mkdir(CGPATH "/test", 0666);
	if (fork() > 0)
		wait(&status);
	else
		run(getpid());
	rmdir(CGPATH "/test");
}

int main(int argc, char **argv)
{
	int i;
	for (i = 0; i < NR_TESTS; i++)
		test();
	return 0;
}
Reported-by: Ricardo Marin Matinata <rmm@br.ibm.com>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@linux.vnet.ibm.com>
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@fb.com>

Pull more thermal managament updates from Zhang Rui:
 "Specifics:

   - Exynos thermal driver refactoring.  Several cleanups, code
     optimization, unused symbols removal, and unused feature removal in
     Exynos thermal driver.  Thanks Lukasz for this effort.

   - Exynos thermal driver support to OF thermal.  After the code
     refactoring, the driver earned the support to OF thermal.  Chip
     thermal data were moved from driver code to DTS, reducing the code
     footprint.  Thanks Lukasz for this.

   - After receiving the OF thermal support, the exynos thermal driver
     now must allow modular build.  Thanks Arnd for detecting, reporting
     and fixing this.

   - Exynos thermal driver support to Exynos 7 SoC.  Thanks Abhilash for
     this.

   - Accurate temperature reporting on Rockchip thermal driver, thanks
     to Caesar.

   - Fix on how OF thermal enables its zones, thanks Lukasz for fixing.

   - Fixes in OF thermal examples under Documentation/.  Thanks Srinivas
     for fixing"

* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/evalenti/linux-soc-thermal:
  thermal: exynos: Add TMU support for Exynos7 SoC
  dts: Documentation: Add documentation for Exynos7 SoC thermal bindings
  cpufreq: exynos: allow modular build
  thermal: Fix examples in DT documentation
  thermal: exynos: Correct sanity check at exynos_report_trigger() function
  thermal: Kconfig: Remove config for not used EXYNOS_THERMAL_CORE
  thermal: exynos: Remove exynos_tmu_data.c file
  thermal: rockchip: make temperature reporting much more accurate
  thermal: exynos: Remove exynos_thermal_common.[c|h] files
  thermal: samsung: core: Exynos TMU rework to use device tree for configuration
  dts: Documentation: Update exynos-thermal.txt example for Exynos5440
  dts: Documentation: Extending documentation entry for exynos-thermal
  cpufreq: exynos: Use device tree to determine if cpufreq cooling should be registered
  thermal: exynos: Modify exynos thermal code to use device tree for cpu cooling configuration
  thermal: exynos: Provide thermal_exynos.h file to be included in device tree files
  thermal: exynos: cosmetic: Correct comment format
  thermal: of: Enable thermal_zoneX when sensor is correctly added

This makes all sync commands uninterruptible and schedules without timeout
so the controller either has to post a completion or the timeout recovery
fails the command. This fixes potential memory or data corruption from
a command timing out too early or woken by a signal. Previously any DMA
buffers mapped for that command would have been released even though we
don't know what the controller is planning to do with those addresses.
Signed-off-by: Keith Busch <keith.busch@intel.com>

We don't track queues in a llist, subscribe to hot-cpu notifications,
or internally retry commands. Delete the unused artifacts.
Signed-off-by: Keith Busch <keith.busch@intel.com>

It should be a logical bitwise AND, not conditional.
Signed-off-by: Keith Busch <keith.busch@intel.com>

The driver has to end unreturned commands at some point even if the
controller has not provided a completion. The driver tried to be safe by
deleting IO queues prior to ending all unreturned commands. That should
cause the controller to internally abort inflight commands, but IO queue
deletion request does not have to be successful, so all bets are off. We
still have to make progress, so to be extra safe, this patch doesn't
clear a queue to release the dma mapping for a command until after the
pci device has been disabled.

This patch removes the special handling during device initialization
so controller recovery can be done all the time. This is possible since
initialization is not inlined with pci probe anymore.
Reported-by: Nilish Choudhury <nilesh.choudhury@oracle.com>
Signed-off-by: Keith Busch <keith.busch@intel.com>

This performs the longest parts of nvme device probe in scheduled work.
This speeds up probe significantly when multiple devices are in use.
Signed-off-by: Keith Busch <keith.busch@intel.com>

This creates a new class type for nvme devices to register their
management character devices with. This is so we do not rely on miscdev
to provide enough minors for as many nvme devices some people plan to
use. The previous limit was approximately 60 NVMe controllers, depending
on the platform and kernel. Now the limit is 1M, which ought to be enough
for anybody.

Since we have a new device class, it makes sense to attach the block
devices under this as well, so part of this patch moves the management
handle initialization prior to the namespaces discovery.
Signed-off-by: Keith Busch <keith.busch@intel.com>

The original translation created collisions on Inquiry VPD 83 for many
existing devices. Newer specifications provide other ways to translate
based on the device's version can be used to create unique identifiers.

Version 1.1 provides an EUI64 field that uniquely identifies each
namespace, and 1.2 added the longer NGUID field for the same reason.
Both follow the IEEE EUI format and readily translate to the SCSI device
identification EUI designator type 2h. For devices implementing either,
the translation will use this type, defaulting to the EUI64 8-byte type if
implemented then NGUID's 16 byte version if not. If neither are provided,
the 1.0 translation is used, and is updated to use the SCSI String format
to guarantee a unique identifier.

Knowing when to use the new fields depends on the nvme controller's
revision. The NVME_VS macro was not decoding this correctly, so that is
fixed in this patch and moved to a more appropriate place.

Since the Identify Namespace structure required an update for the NGUID
field, this patch adds the remaining new 1.2 fields to the structure.
Signed-off-by: Keith Busch <keith.busch@intel.com>

Adds support for NVMe metadata formats and exposes block devices for
all namespaces regardless of their format. Namespace formats that are
unusable will have disk capacity set to 0, but a handle to the block
device is created to simplify device management. A namespace is not
usable when the format requires host interleave block and metadata in
single buffer, has no provisioned storage, or has better data but failed
to register with blk integrity.

The namespace has to be scanned in two phases to support separate
metadata formats. The first establishes the sector size and capacity
prior to invoking add_disk. If metadata is required, the capacity will
be temporarilly set to 0 until it can be revalidated and registered with
the integrity extenstions after add_disk completes.

The driver relies on the integrity extensions to provide the metadata
buffer. NVMe requires this be a single physically contiguous region,
so only one integrity segment is allowed per command. If the metadata
is used for T10 PI, the driver provides mappings to save and restore
the reftag physical block translation. The driver provides no-op
functions for generate and verify if metadata is not used for protection
information. This way the setup is always provided by the block layer.

If a request does not supply a required metadata buffer, the command
is failed with bad address. This could only happen if a user manually
disables verify/generate on such a disk. The only exception to where
this is okay is if the controller is capable of stripping/generating
the metadata, which is possible on some types of formats.

The metadata scatter gather list now occupies the spot in the nvme_iod
that used to be used to link retryable IOD's, but we don't do that
anymore, so the field was unused.
Signed-off-by: Keith Busch <keith.busch@intel.com>

Since _PAGE_PROTNONE aliases _PAGE_GLOBAL it is only valid if
_PAGE_PRESENT is clear.  Make pte_protnone() and pmd_protnone() check
for this.

This fixes a 64-bit Xen PV guest regression introduced by 8a0516ed
("mm: convert p[te|md]_numa users to p[te|md]_protnone_numa").  Any
userspace process would endlessly fault.

In a 64-bit PV guest, userspace page table entries have _PAGE_GLOBAL set
by the hypervisor.  This meant that any fault on a present userspace
entry (e.g., a write to a read-only mapping) would be misinterpreted as
a NUMA hinting fault and the fault would not be correctly handled,
resulting in the access endlessly faulting.
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull btrfs updates from Chris Mason:
 "This pull is mostly cleanups and fixes:

   - The raid5/6 cleanups from Zhao Lei fixup some long standing warts
     in the code and add improvements on top of the scrubbing support
     from 3.19.

   - Josef has round one of our ENOSPC fixes coming from large btrfs
     clusters here at FB.

   - Dave Sterba continues a long series of cleanups (thanks Dave), and
     Filipe continues hammering on corner cases in fsync and others

  This all was held up a little trying to track down a use-after-free in
  btrfs raid5/6.  It's not clear yet if this is just made easier to
  trigger with this pull or if its a new bug from the raid5/6 cleanups.
  Dave Sterba is the only one to trigger it so far, but he has a
  consistent way to reproduce, so we'll get it nailed shortly"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (68 commits)
  Btrfs: don't remove extents and xattrs when logging new names
  Btrfs: fix fsync data loss after adding hard link to inode
  Btrfs: fix BUG_ON in btrfs_orphan_add() when delete unused block group
  Btrfs: account for large extents with enospc
  Btrfs: don't set and clear delalloc for O_DIRECT writes
  Btrfs: only adjust outstanding_extents when we do a short write
  btrfs: Fix out-of-space bug
  Btrfs: scrub, fix sleep in atomic context
  Btrfs: fix scheduler warning when syncing log
  Btrfs: Remove unnecessary placeholder in btrfs_err_code
  btrfs: cleanup init for list in free-space-cache
  btrfs: delete chunk allocation attemp when setting block group ro
  btrfs: clear bio reference after submit_one_bio()
  Btrfs: fix scrub race leading to use-after-free
  Btrfs: add missing cleanup on sysfs init failure
  Btrfs: fix race between transaction commit and empty block group removal
  btrfs: add more checks to btrfs_read_sys_array
  btrfs: cleanup, rename a few variables in btrfs_read_sys_array
  btrfs: add checks for sys_chunk_array sizes
  btrfs: more superblock checks, lower bounds on devices and sectorsize/nodesize
  ...

Pull Ceph changes from Sage Weil:
 "On the RBD side, there is a conversion to blk-mq from Christoph,
  several long-standing bug fixes from Ilya, and some cleanup from
  Rickard Strandqvist.

  On the CephFS side there is a long list of fixes from Zheng, including
  improved session handling, a few IO path fixes, some dcache management
  correctness fixes, and several blocking while !TASK_RUNNING fixes.

  The core code gets a few cleanups and Chaitanya has added support for
  TCP_NODELAY (which has been used on the server side for ages but we
  somehow missed on the kernel client).

  There is also an update to MAINTAINERS to fix up some email addresses
  and reflect that Ilya and Zheng are doing most of the maintenance for
  RBD and CephFS these days.  Do not be surprised to see a pull request
  come from one of them in the future if I am unavailable for some
  reason"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: (27 commits)
  MAINTAINERS: update Ceph and RBD maintainers
  libceph: kfree() in put_osd() shouldn't depend on authorizer
  libceph: fix double __remove_osd() problem
  rbd: convert to blk-mq
  ceph: return error for traceless reply race
  ceph: fix dentry leaks
  ceph: re-send requests when MDS enters reconnecting stage
  ceph: show nocephx_require_signatures and notcp_nodelay options
  libceph: tcp_nodelay support
  rbd: do not treat standalone as flatten
  ceph: fix atomic_open snapdir
  ceph: properly mark empty directory as complete
  client: include kernel version in client metadata
  ceph: provide seperate {inode,file}_operations for snapdir
  ceph: fix request time stamp encoding
  ceph: fix reading inline data when i_size > PAGE_SIZE
  ceph: avoid block operation when !TASK_RUNNING (ceph_mdsc_close_sessions)
  ceph: avoid block operation when !TASK_RUNNING (ceph_get_caps)
  ceph: avoid block operation when !TASK_RUNNING (ceph_mdsc_sync)
  rbd: fix error paths in rbd_dev_refresh()
  ...

Pull thermal managament updates from Zhang Rui:
 "Specifics:

   - Abstract the code and introduce helper functions for all int340x
     thermal drivers.  From: Srinivas Pandruvada.

   - Reorganize the ACPI LPAT table support code so that it can be
     shared for both ACPI PMIC driver and int340x thermal driver.

   - Add support for Braswell in intel_soc_dts thermal driver.

   - a couple of small fixes/cleanups for step_wise governor and int340x
     thermal driver"

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux:
  Thermal/int340x_thermal: remove unused uuids.
  thermal: step_wise: spelling fixes
  thermal: int340x: fix sparse warning
  Thermal/int340x: LPAT conversion for temperature
  ACPI / PMIC: Use common LPAT table handling functions
  ACPI / LPAT: Common table processing functions
  thermal: Intel SoC DTS: Add Braswell support
  Thermal/int340x/int3402: Provide notification support
  Thermal/int340x/processor_thermal: Add thermal zone support
  Thermal/int340x/int3403: Use int340x thermal API
  Thermal/int340x/int3402: Use int340x thermal API
  Thermal/int340x: Add common thermal zone handler

Pull two EDAC fixes from Borislav Petkov:

 - A fix to sb_edac for proper detection on SNB machines

 - A fix to amd64_edac to not explode on Numascale machines with more
   than 16 memory controllers, from Daniel J Blueman.

* tag 'edac_fixes_for_3.20' of git://git.kernel.org/pub/scm/linux/kernel/git/bp/bp:
  EDAC, amd64_edac: Prevent OOPS with >16 memory controllers
  sb_edac: Fix detection on SNB machines

Merge tag 'platform-drivers-x86-v3.20-1' of git://git.infradead.org/users/dvhart/linux-platform-drivers-x86

Pull platform driver update from Darren Hart:
 "This includes a significant update to the toshiba_acpi driver,
  bringing it to feature parity with the Windows driver, followed by
  some needed cleanups.

  The other changes are mostly minor updates, quirks, sparse fixes, or
  cleanups.

  Details:

   - toshiba_acpi:
       Add support for missing features from the Windows driver, bump the
       sysfs version, and clean up the driver.

   - thinkpad_acpi:
       BIOS string versions, unhandled hkey events.

   - msamsung-laptop:
       Add native backlight quirk, enable better lid handling.

   - intel_scu_ipc:
       Read resources from PCI configuration

   - other:
       Fix sparse warnings, general cleanups"

* tag 'platform-drivers-x86-v3.20-1' of git://git.infradead.org/users/dvhart/linux-platform-drivers-x86: (34 commits)
  toshiba_acpi: Cleanup GPL header
  toshiba_acpi: Cleanup comment blocks and capitalization
  toshiba_acpi: Make use of DEVICE_ATTR_{RO, RW} macros
  toshiba_acpi: Drop the toshiba_ prefix from sysfs function names
  toshiba_acpi: Move sysfs function and struct declarations further down
  Documentation/ABI: Add file describing the sysfs entries for toshiba_acpi
  toshiba_acpi: Clean file according to coding style
  toshiba_acpi: Bump version number to 0.21
  toshiba_acpi: Add support to enable/disable USB 3
  toshiba_acpi: Add support for Panel Power ON
  toshiba_acpi: Add support for Keyboard functions mode
  toshiba_acpi: Add fan entry to sysfs
  toshiba_acpi: Add version entry to sysfs
  thinkpad_acpi: support new BIOS version string pattern
  thinkpad_acpi: unhandled hkey event
  toshiba_acpi: Make toshiba_eco_mode_available more robust
  classmate-laptop: Fix sparse warning (0 as NULL)
  Sony-laptop: Fix sparse warning (make undeclared var static)
  thinkpad_acpi.c: Fix sparse warning (make undeclared var static)
  samsung-laptop.c: Prefer kstrtoint over single variable sscanf
  ...

Pull kconfig updates from Michal Marek:
 "Yann E Morin was supposed to take over kconfig maintainership, but
  this hasn't happened.  So I'm sending a few kconfig patches that I
  collected:

   - Fix for missing va_end in kconfig
   - merge_config.sh displays used if given too few arguments
   - s/boolean/bool/ in Kconfig files for consistency, with the plan to
     only support bool in the future"

* 'kconfig' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
  kconfig: use va_end to match corresponding va_start
  merge_config.sh: Display usage if given too few arguments
  kconfig: use bool instead of boolean for type definition attributes

Pull misc kbuild changes from Michal Marek:
 "Just a few non-critical kbuild changes:

   - builddeb adds the actual distribution name in the changelog
   - documentation fixes"

* 'misc' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
  kbuild: trivial - fix the help doc of CONFIG_CC_OPTIMIZE_FOR_SIZE
  kbuild: Update documentation of clean-files and clean-dirs
  builddeb: Try to determine distribution
  builddeb: Update year and git repository URL in debian/copyright

- add Ilya, drop Yehuda as an RBD maintainer
- add Zheng as a Ceph maintainer
- update Yehuda and Sage's emails
Signed-off-by: Sage Weil <sage@redhat.com>

Pull kbuild updates from Michal Marek:

 - several cleanups in kbuild

 - serialize multiple *config targets so that 'make defconfig kvmconfig'
   works

 - The cc-ifversion macro got support for an else-branch

* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
  kbuild,gcov: simplify kernel/gcov/Makefile more
  kbuild: allow cc-ifversion to have the argument for false condition
  kbuild,gcov: simplify kernel/gcov/Makefile
  kbuild,gcov: remove unnecessary workaround
  kbuild: do not add $(call ...) to invoke cc-version or cc-fullversion
  kbuild: fix cc-ifversion macro
  kbuild: drop $(version_h) from MRPROPER_FILES
  kbuild: use mixed-targets when two or more config targets are given
  kbuild: remove redundant line from bounds.h/asm-offsets.h
  kbuild: merge bounds.h and asm-offsets.h rules
  kbuild: Drop support for clean-rule

a255651d ("ceph: ensure auth ops are defined before use") made
kfree() in put_osd() conditional on the authorizer.  A mechanical
mistake most likely - fix it.

Cc: Alex Elder <elder@linaro.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Sage Weil <sage@redhat.com>
Reviewed-by: Alex Elder <elder@linaro.org>

It turns out it's possible to get __remove_osd() called twice on the
same OSD.  That doesn't sit well with rb_erase() - depending on the
shape of the tree we can get a NULL dereference, a soft lockup or
a random crash at some point in the future as we end up touching freed
memory.  One scenario that I was able to reproduce is as follows:

            <osd3 is idle, on the osd lru list>
<con reset - osd3>
con_fault_finish()
  osd_reset()
                              <osdmap - osd3 down>
                              ceph_osdc_handle_map()
                                <takes map_sem>
                                kick_requests()
                                  <takes request_mutex>
                                  reset_changed_osds()
                                    __reset_osd()
                                      __remove_osd()
                                  <releases request_mutex>
                                <releases map_sem>
    <takes map_sem>
    <takes request_mutex>
    __kick_osd_requests()
      __reset_osd()
        __remove_osd() <-- !!!

A case can be made that osd refcounting is imperfect and reworking it
would be a proper resolution, but for now Sage and I decided to fix
this by adding a safe guard around __remove_osd().

Fixes: http://tracker.ceph.com/issues/8087

Cc: Sage Weil <sage@redhat.com>
Cc: stable@vger.kernel.org # 3.9+: 7c6e6fc5: libceph: assert both regular and lingering lists in __remove_osd()
Cc: stable@vger.kernel.org # 3.9+: cc9f1f51: libceph: change from BUG to WARN for __remove_osd() asserts
Cc: stable@vger.kernel.org # 3.9+
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Sage Weil <sage@redhat.com>
Reviewed-by: Alex Elder <elder@linaro.org>

This converts the rbd driver to use the blk-mq infrastructure.  Except
for switching to a per-request work item this is almost mechanical.

This was tested by Alexandre DERUMIER in November, and found to give
him 120000 iops, although the only comparism available was an old
3.10 kernel which gave 80000iops.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <elder@linaro.org>
[idryomov@gmail.com: context, blk_mq_init_queue() EH]
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

When we receives traceless reply for request that created new inode,
we re-send a lookup request to MDS get information of the newly created
inode. (VFS expects FS' callback return an inode in create case)
This breaks one request into two requests. Other client may modify or
move to the new inode in the middle.

When the race happens, ceph_handle_notrace_create() unconditionally
links the dentry for 'create' operation to the inode returned by lookup.
This may confuse VFS when the inode is a directory (VFS does not allow
multiple linkages for directory inode).

This patch makes ceph_handle_notrace_create() when it detect a race.
This event should be rare and it happens only when we talk to old MDS.
Recent MDS does not send traceless reply for request that creates new
inode.
Signed-off-by: Yan, Zheng <zyan@redhat.com>

Signed-off-by: Yan, Zheng <zyan@redhat.com>

So that MDS can check if any request is already completed and process
completed requests in clientreplay stage. When completed requests are
processed in clientreplay stage, MDS can avoid sending traceless
replies.
Signed-off-by: Yan, Zheng <zyan@redhat.com>

Signed-off-by: Ilya Dryomov <idryomov@redhat.com>

TCP_NODELAY socket option set on connection sockets,
disables Nagle’s algorithm and improves latency characteristics.
tcp_nodelay(default)/notcp_nodelay option flags provided to
enable/disable setting the socket option.
Signed-off-by: Chaitanya Huilgol <chaitanya.huilgol@sandisk.com>
[idryomov@redhat.com: NO_TCP_NODELAY -> TCP_NODELAY, minor adjustments]
Signed-off-by: Ilya Dryomov <idryomov@redhat.com>

If the clone is resized down to 0, it becomes standalone.  If such
resize is carried over while an image is mapped we would detect this
and call rbd_dev_parent_put() which means "let go of all parent state,
including the spec(s) of parent images(s)".  This leads to a mismatch
between "rbd info" and sysfs parent fields, so a fix is in order.

    # rbd create --image-format 2 --size 1 foo
    # rbd snap create foo@snap
    # rbd snap protect foo@snap
    # rbd clone foo@snap bar
    # DEV=$(rbd map bar)
    # rbd resize --allow-shrink --size 0 bar
    # rbd resize --size 1 bar
    # rbd info bar | grep parent
            parent: rbd/foo@snap

Before:

    # cat /sys/bus/rbd/devices/0/parent
    (no parent image)

After:

    # cat /sys/bus/rbd/devices/0/parent
    pool_id 0
    pool_name rbd
    image_id 10056b8b4567
    image_name foo
    snap_id 2
    snap_name snap
    overlap 0
Signed-off-by: Ilya Dryomov <idryomov@redhat.com>
Reviewed-by: Josh Durgin <jdurgin@redhat.com>
Reviewed-by: Alex Elder <elder@linaro.org>

ceph_handle_snapdir() checks ceph_mdsc_do_request()'s return value
and creates snapdir inode if it's -ENOENT
Signed-off-by: Yan, Zheng <zyan@redhat.com>

ceph_add_cap() calls __check_cap_issue(), which clears directory
inode' complete flag. so we should set the complete flag for empty
directory should be set after calling ceph_add_cap().
Signed-off-by: Yan, Zheng <zyan@redhat.com>

Signed-off-by: Yan, Zheng <zyan@redhat.com>

remove all unsupported operations from {inode,file}_operations.
Signed-off-by: Yan, Zheng <zyan@redhat.com>

struct timespec uses 'long' to present second and nanosecond. 'long'
is 64 bits on 64bits machine. ceph MDS expects time stamp to be
encoded as struct ceph_timespec, which uses 'u32' to present second
and nanosecond.
Signed-off-by: Yan, Zheng <zyan@redhat.com>

when inode has inline data but its size > PAGE_SIZE (it was truncated
to larger size), previous direct read code return -EIO. This patch adds
code to return zeros for data whose offset > PAGE_SIZE.
Signed-off-by: Yan, Zheng <zyan@redhat.com>

use an atomic variable to track number of sessions, this can avoid block
operation inside wait loops.
Signed-off-by: Yan, Zheng <zyan@redhat.com>

we should not do block operation in wait_event_interruptible()'s condition
check function, but reading inline data can block. so move the read inline
data code to ceph_get_caps()
Signed-off-by: Yan, Zheng <zyan@redhat.com>

check_cap_flush() calls mutex_lock(), which may block. So we can't
use it as condition check function for wait_event();
Signed-off-by: Yan, Zheng <zyan@redhat.com>

header_rwsem should be released on errors.  Also remove useless
rbd_dev->mapping.size != rbd_dev->header.image_size test.
Signed-off-by: Ilya Dryomov <idryomov@redhat.com>