BMC/Intel-BMC/linux.git/fs/block_dev.c, branch v4.2

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2015-07-05T02:36:06+00:00

Pull more vfs updates from Al Viro: "Assorted VFS fixes and related cleanups (IMO the most interesting in that part are f_path-related things and Eric's descriptor-related stuff). UFS regression fixes (it got broken last cycle). 9P fixes. fs-cache series, DAX patches, Jan's file_remove_suid() work" [ I'd say this is much more than "fixes and related cleanups". The file_table locking rule change by Eric Dumazet is a rather big and fundamental update even if the patch isn't huge. - Linus ] * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (49 commits) 9p: cope with bogus responses from server in p9_client_{read,write} p9_client_write(): avoid double p9_free_req() 9p: forgetting to cancel request on interrupted zero-copy RPC dax: bdev_direct_access() may sleep block: Add support for DAX reads/writes to block devices dax: Use copy_from_iter_nocache dax: Add block size note to documentation fs/file.c: __fget() and dup2() atomicity rules fs/file.c: don't acquire files->file_lock in fd_install() fs:super:get_anon_bdev: fix race condition could cause dev exceed its upper limitation vfs: avoid creation of inode number 0 in get_next_ino namei: make set_root_rcu() return void make simple_positive() public ufs: use dir_pages instead of ufs_dir_pages() pagemap.h: move dir_pages() over there remove the pointless include of lglock.h fs: cleanup slight list_entry abuse xfs: Correctly lock inode when removing suid and file capabilities fs: Call security_ops->inode_killpriv on truncate fs: Provide function telling whether file_remove_privs() will do anything ...

dax: bdev_direct_access() may sleep

2015-07-04T19:56:57+00:00

The brd driver is the only in-tree driver that may sleep currently. After some discussion on linux-fsdevel, we decided that any driver may choose to sleep in its ->direct_access method. To ensure that all callers of bdev_direct_access() are prepared for this, add a call to might_sleep(). Signed-off-by: Matthew Wilcox Signed-off-by: Al Viro

block: Add support for DAX reads/writes to block devices

2015-07-04T19:56:57+00:00

If a block device supports the ->direct_access methods, bypass the normal DIO path and use DAX to go straight to memcpy() instead of allocating a DIO and a BIO. Includes support for the DIO_SKIP_DIO_COUNT flag in DAX, as is done in do_blockdev_direct_IO(). Signed-off-by: Matthew Wilcox Signed-off-by: Al Viro

Merge branch 'for-linus' of git://git.kernel.dk/linux-block

2015-07-01T02:46:34+00:00

Pull more block layer patches from Jens Axboe: "A few later arrivers that I didn't fold into the first pull request, so we had a chance to run some testing. This contains: - NVMe: - Set of fixes from Keith - 4.4 and earlier gcc build fix from Andrew - small set of xen-blk{back,front} fixes from Bob Liu. - warnings fix for bogus inline statement in I_BDEV() from Geert. - error code fixup for SG_IO ioctl from Paolo Bonzini" * 'for-linus' of git://git.kernel.dk/linux-block: drivers/block/nvme-core.c: fix build with gcc-4.4.4 bdi: Remove "inline" keyword from exported I_BDEV() implementation block: fix bogus EFAULT error from SG_IO ioctl NVMe: Fix filesystem deadlock on removal NVMe: Failed controller initialization fixes NVMe: Unify controller probe and resume NVMe: Don't use fake status on cancelled command NVMe: Fix device cleanup on initialization failure drivers: xen-blkfront: only talk_to_blkback() when in XenbusStateInitialising xen/block: add multi-page ring support driver: xen-blkfront: move talk_to_blkback to a more suitable place drivers: xen-blkback: delay pending_req allocation to connect_ring

Merge tag 'libnvdimm-for-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/nvdimm

2015-06-29T17:34:42+00:00

Pull libnvdimm subsystem from Dan Williams: "The libnvdimm sub-system introduces, in addition to the libnvdimm-core, 4 drivers / enabling modules: NFIT: Instantiates an "nvdimm bus" with the core and registers memory devices (NVDIMMs) enumerated by the ACPI 6.0 NFIT (NVDIMM Firmware Interface table). After registering NVDIMMs the NFIT driver then registers "region" devices. A libnvdimm-region defines an access mode and the boundaries of persistent memory media. A region may span multiple NVDIMMs that are interleaved by the hardware memory controller. In turn, a libnvdimm-region can be carved into a "namespace" device and bound to the PMEM or BLK driver which will attach a Linux block device (disk) interface to the memory. PMEM: Initially merged in v4.1 this driver for contiguous spans of persistent memory address ranges is re-worked to drive PMEM-namespaces emitted by the libnvdimm-core. In this update the PMEM driver, on x86, gains the ability to assert that writes to persistent memory have been flushed all the way through the caches and buffers in the platform to persistent media. See memcpy_to_pmem() and wmb_pmem(). BLK: This new driver enables access to persistent memory media through "Block Data Windows" as defined by the NFIT. The primary difference of this driver to PMEM is that only a small window of persistent memory is mapped into system address space at any given point in time. Per-NVDIMM windows are reprogrammed at run time, per-I/O, to access different portions of the media. BLK-mode, by definition, does not support DAX. BTT: This is a library, optionally consumed by either PMEM or BLK, that converts a byte-accessible namespace into a disk with atomic sector update semantics (prevents sector tearing on crash or power loss). The sinister aspect of sector tearing is that most applications do not know they have a atomic sector dependency. At least today's disk's rarely ever tear sectors and if they do one almost certainly gets a CRC error on access. NVDIMMs will always tear and always silently. Until an application is audited to be robust in the presence of sector-tearing the usage of BTT is recommended. Thanks to: Ross Zwisler, Jeff Moyer, Vishal Verma, Christoph Hellwig, Ingo Molnar, Neil Brown, Boaz Harrosh, Robert Elliott, Matthew Wilcox, Andy Rudoff, Linda Knippers, Toshi Kani, Nicholas Moulin, Rafael Wysocki, and Bob Moore" * tag 'libnvdimm-for-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/nvdimm: (33 commits) arch, x86: pmem api for ensuring durability of persistent memory updates libnvdimm: Add sysfs numa_node to NVDIMM devices libnvdimm: Set numa_node to NVDIMM devices acpi: Add acpi_map_pxm_to_online_node() libnvdimm, nfit: handle unarmed dimms, mark namespaces read-only pmem: flag pmem block devices as non-rotational libnvdimm: enable iostat pmem: make_request cleanups libnvdimm, pmem: fix up max_hw_sectors libnvdimm, blk: add support for blk integrity libnvdimm, btt: add support for blk integrity fs/block_dev.c: skip rw_page if bdev has integrity libnvdimm: Non-Volatile Devices tools/testing/nvdimm: libnvdimm unit test infrastructure libnvdimm, nfit, nd_blk: driver for BLK-mode access persistent memory nd_btt: atomic sector updates libnvdimm: infrastructure for btt devices libnvdimm: write blk label set libnvdimm: write pmem label set libnvdimm: blk labels and namespace instantiation ...

bdi: Remove "inline" keyword from exported I_BDEV() implementation

2015-06-27T17:44:12+00:00

With gcc 3.4.6/4.1.2/4.2.4 (not with 4.4.7/4.6.4/4.8.4): CC fs/block_dev.o include/linux/fs.h:804: warning: ‘I_BDEV’ declared inline after being called include/linux/fs.h:804: warning: previous declaration of ‘I_BDEV’ was here Commit a212b105b07d75b4 ("bdi: make inode_to_bdi() inline") added a caller of I_BDEV() in a header file, exposing the bogus "inline" on the exported implementation. Drop the "inline" keyword to fix this. Signed-off-by: Geert Uytterhoeven Signed-off-by: Jens Axboe

fs/block_dev.c: skip rw_page if bdev has integrity

2015-06-26T15:23:38+00:00

If a block device has bio integrity enabled, rw_page will bypass the integrity payload, which is undesirable. Skip rw_page if this is the case. Currently brd and zram provide rw_page, and the proposed 'nd' drivers will too. Cc: Jens Axboe Cc: Martin K. Petersen Suggested-by: Matthew Wilcox Signed-off-by: Vishal Verma Signed-off-by: Dan Williams

bdi: make inode_to_bdi() inline

2015-06-02T14:33:34+00:00

Now that bdi definitions are moved to backing-dev-defs.h, backing-dev.h can include blkdev.h and inline inode_to_bdi() without worrying about introducing circular include dependency. The function gets called from hot paths and fairly trivial. This patch makes inode_to_bdi() and sb_is_blkdev_sb() that the function calls inline. blockdev_superblock and noop_backing_dev_info are EXPORT_GPL'd to allow the inline functions to be used from modules. While at it, make sb_is_blkdev_sb() return bool instead of int. v2: Fixed typo in description as suggested by Jan. Signed-off-by: Tejun Heo Reviewed-by: Jens Axboe Cc: Christoph Hellwig Signed-off-by: Jens Axboe

writeback: separate out include/linux/backing-dev-defs.h

2015-06-02T14:33:34+00:00

With the planned cgroup writeback support, backing-dev related declarations will be more widely used across block and cgroup; unfortunately, including backing-dev.h from include/linux/blkdev.h makes cyclic include dependency quite likely. This patch separates out backing-dev-defs.h which only has the essential definitions and updates blkdev.h to include it. c files which need access to more backing-dev details now include backing-dev.h directly. This takes backing-dev.h off the common include dependency chain making it a lot easier to use it across block and cgroup. v2: fs/fat build failure fixed. Signed-off-by: Tejun Heo Reviewed-by: Jan Kara Cc: Jens Axboe Signed-off-by: Jens Axboe

direct-io: only inc/dec inode->i_dio_count for file systems

2015-04-24T19:45:28+00:00

do_blockdev_direct_IO() increments and decrements the inode ->i_dio_count for each IO operation. It does this to protect against truncate of a file. Block devices don't need this sort of protection. For a capable multiqueue setup, this atomic int is the only shared state between applications accessing the device for O_DIRECT, and it presents a scaling wall for that. In my testing, as much as 30% of system time is spent incrementing and decrementing this value. A mixed read/write workload improved from ~2.5M IOPS to ~9.6M IOPS, with better latencies too. Before: clat percentiles (usec): | 1.00th=[ 33], 5.00th=[ 34], 10.00th=[ 34], 20.00th=[ 34], | 30.00th=[ 34], 40.00th=[ 34], 50.00th=[ 35], 60.00th=[ 35], | 70.00th=[ 35], 80.00th=[ 35], 90.00th=[ 37], 95.00th=[ 80], | 99.00th=[ 98], 99.50th=[ 151], 99.90th=[ 155], 99.95th=[ 155], | 99.99th=[ 165] After: clat percentiles (usec): | 1.00th=[ 95], 5.00th=[ 108], 10.00th=[ 129], 20.00th=[ 149], | 30.00th=[ 155], 40.00th=[ 161], 50.00th=[ 167], 60.00th=[ 171], | 70.00th=[ 177], 80.00th=[ 185], 90.00th=[ 201], 95.00th=[ 270], | 99.00th=[ 390], 99.50th=[ 398], 99.90th=[ 418], 99.95th=[ 422], | 99.99th=[ 438] In other setups, Robert Elliott reported seeing good performance improvements: https://lkml.org/lkml/2015/4/3/557 The more applications accessing the device, the worse it gets. Add a new direct-io flags, DIO_SKIP_DIO_COUNT, which tells do_blockdev_direct_IO() that it need not worry about incrementing or decrementing the inode i_dio_count for this caller. Cc: Andrew Morton Cc: Christoph Hellwig Cc: Theodore Ts'o Cc: Elliott, Robert (Server Storage) Cc: Al Viro Signed-off-by: Jens Axboe Signed-off-by: Al Viro