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* Merge 4.4.201 into android-4.4-pGreg Kroah-Hartman2019-11-14
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Changes in 4.4.201 CDC-NCM: handle incomplete transfer of MTU net: fix data-race in neigh_event_send() NFC: fdp: fix incorrect free object NFC: st21nfca: fix double free qede: fix NULL pointer deref in __qede_remove() nfc: netlink: fix double device reference drop ALSA: bebob: fix to detect configured source of sampling clock for Focusrite Saffire Pro i/o series ALSA: hda/ca0132 - Fix possible workqueue stall mm, vmstat: hide /proc/pagetypeinfo from normal users dump_stack: avoid the livelock of the dump_lock perf tools: Fix time sorting drm/radeon: fix si_enable_smc_cac() failed issue ceph: fix use-after-free in __ceph_remove_cap() iio: imu: adis16480: make sure provided frequency is positive netfilter: nf_tables: Align nft_expr private data to 64-bit netfilter: ipset: Fix an error code in ip_set_sockfn_get() can: usb_8dev: fix use-after-free on disconnect can: c_can: c_can_poll(): only read status register after status IRQ can: peak_usb: fix a potential out-of-sync while decoding packets can: gs_usb: gs_can_open(): prevent memory leak can: peak_usb: fix slab info leak drivers: usb: usbip: Add missing break statement to switch configfs: fix a deadlock in configfs_symlink() PCI: tegra: Enable Relaxed Ordering only for Tegra20 & Tegra30 scsi: qla2xxx: fixup incorrect usage of host_byte scsi: lpfc: Honor module parameter lpfc_use_adisc ipvs: move old_secure_tcp into struct netns_ipvs bonding: fix unexpected IFF_BONDING bit unset usb: fsl: Check memory resource before releasing it usb: gadget: udc: atmel: Fix interrupt storm in FIFO mode. usb: gadget: composite: Fix possible double free memory bug usb: gadget: configfs: fix concurrent issue between composite APIs perf/x86/amd/ibs: Fix reading of the IBS OpData register and thus precise RIP validity USB: Skip endpoints with 0 maxpacket length scsi: qla2xxx: stop timer in shutdown path net: hisilicon: Fix "Trying to free already-free IRQ" NFSv4: Don't allow a cached open with a revoked delegation igb: Fix constant media auto sense switching when no cable is connected e1000: fix memory leaks can: flexcan: disable completely the ECC mechanism mm/filemap.c: don't initiate writeback if mapping has no dirty pages cgroup,writeback: don't switch wbs immediately on dead wbs if the memcg is dead net: prevent load/store tearing on sk->sk_stamp drm/i915/gtt: Add read only pages to gen8_pte_encode drm/i915/gtt: Read-only pages for insert_entries on bdw+ drm/i915/gtt: Disable read-only support under GVT drm/i915: Rename gen7 cmdparser tables drm/i915: Disable Secure Batches for gen6+ drm/i915: Remove Master tables from cmdparser drm/i915: Add support for mandatory cmdparsing drm/i915: Support ro ppgtt mapped cmdparser shadow buffers drm/i915: Allow parsing of unsized batches drm/i915: Add gen9 BCS cmdparsing drm/i915/cmdparser: Add support for backward jumps drm/i915/cmdparser: Ignore Length operands during command matching drm/i915: Lower RM timeout to avoid DSI hard hangs drm/i915/gen8+: Add RC6 CTX corruption WA drm/i915/cmdparser: Fix jump whitelist clearing Linux 4.4.201 Change-Id: Ifc1fa5b9734f244745b862c6dbf7e34b73245806 Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
| * cgroup,writeback: don't switch wbs immediately on dead wbs if the memcg is deadTejun Heo2019-11-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 65de03e251382306a4575b1779c57c87889eee49 upstream. cgroup writeback tries to refresh the associated wb immediately if the current wb is dead. This is to avoid keeping issuing IOs on the stale wb after memcg - blkcg association has changed (ie. when blkcg got disabled / enabled higher up in the hierarchy). Unfortunately, the logic gets triggered spuriously on inodes which are associated with dead cgroups. When the logic is triggered on dead cgroups, the attempt fails only after doing quite a bit of work allocating and initializing a new wb. While c3aab9a0bd91 ("mm/filemap.c: don't initiate writeback if mapping has no dirty pages") alleviated the issue significantly as it now only triggers when the inode has dirty pages. However, the condition can still be triggered before the inode is switched to a different cgroup and the logic simply doesn't make sense. Skip the immediate switching if the associated memcg is dying. This is a simplified version of the following two patches: * https://lore.kernel.org/linux-mm/20190513183053.GA73423@dennisz-mbp/ * http://lkml.kernel.org/r/156355839560.2063.5265687291430814589.stgit@buzz Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Fixes: e8a7abf5a5bd ("writeback: disassociate inodes from dying bdi_writebacks") Acked-by: Dennis Zhou <dennis@kernel.org> Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | Merge 4.4.181 into android-4.4-pGreg Kroah-Hartman2019-06-11
|\| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Changes in 4.4.181 x86/speculation/mds: Revert CPU buffer clear on double fault exit x86/speculation/mds: Improve CPU buffer clear documentation ARM: exynos: Fix a leaked reference by adding missing of_node_put crypto: vmx - fix copy-paste error in CTR mode crypto: crct10dif-generic - fix use via crypto_shash_digest() crypto: x86/crct10dif-pcl - fix use via crypto_shash_digest() ALSA: usb-audio: Fix a memory leak bug ALSA: hda/hdmi - Consider eld_valid when reporting jack event ALSA: hda/realtek - EAPD turn on later ASoC: max98090: Fix restore of DAPM Muxes ASoC: RT5677-SPI: Disable 16Bit SPI Transfers mm/mincore.c: make mincore() more conservative ocfs2: fix ocfs2 read inode data panic in ocfs2_iget mfd: da9063: Fix OTP control register names to match datasheets for DA9063/63L tty/vt: fix write/write race in ioctl(KDSKBSENT) handler ext4: actually request zeroing of inode table after grow ext4: fix ext4_show_options for file systems w/o journal Btrfs: do not start a transaction at iterate_extent_inodes() bcache: fix a race between cache register and cacheset unregister bcache: never set KEY_PTRS of journal key to 0 in journal_reclaim() ipmi:ssif: compare block number correctly for multi-part return messages crypto: gcm - Fix error return code in crypto_gcm_create_common() crypto: gcm - fix incompatibility between "gcm" and "gcm_base" crypto: chacha20poly1305 - set cra_name correctly crypto: salsa20 - don't access already-freed walk.iv crypto: arm/aes-neonbs - don't access already-freed walk.iv writeback: synchronize sync(2) against cgroup writeback membership switches fs/writeback.c: use rcu_barrier() to wait for inflight wb switches going into workqueue when umount ext4: zero out the unused memory region in the extent tree block ALSA: hda/realtek - Fix for Lenovo B50-70 inverted internal microphone bug KVM: x86: Skip EFER vs. guest CPUID checks for host-initiated writes net: avoid weird emergency message net/mlx4_core: Change the error print to info print ppp: deflate: Fix possible crash in deflate_init tipc: switch order of device registration to fix a crash tipc: fix modprobe tipc failed after switch order of device registration stm class: Fix channel free in stm output free path md: add mddev->pers to avoid potential NULL pointer dereference intel_th: msu: Fix single mode with IOMMU of: fix clang -Wunsequenced for be32_to_cpu() cifs: fix strcat buffer overflow and reduce raciness in smb21_set_oplock_level() media: ov6650: Fix sensor possibly not detected on probe NFS4: Fix v4.0 client state corruption when mount clk: tegra: Fix PLLM programming on Tegra124+ when PMC overrides divider fuse: fix writepages on 32bit fuse: honor RLIMIT_FSIZE in fuse_file_fallocate iommu/tegra-smmu: Fix invalid ASID bits on Tegra30/114 ceph: flush dirty inodes before proceeding with remount tracing: Fix partial reading of trace event's id file memory: tegra: Fix integer overflow on tick value calculation perf intel-pt: Fix instructions sampling rate perf intel-pt: Fix improved sample timestamp perf intel-pt: Fix sample timestamp wrt non-taken branches fbdev: sm712fb: fix brightness control on reboot, don't set SR30 fbdev: sm712fb: fix VRAM detection, don't set SR70/71/74/75 fbdev: sm712fb: fix white screen of death on reboot, don't set CR3B-CR3F fbdev: sm712fb: fix boot screen glitch when sm712fb replaces VGA fbdev: sm712fb: fix crashes during framebuffer writes by correctly mapping VRAM fbdev: sm712fb: fix support for 1024x768-16 mode fbdev: sm712fb: use 1024x768 by default on non-MIPS, fix garbled display fbdev: sm712fb: fix crashes and garbled display during DPMS modesetting PCI: Mark Atheros AR9462 to avoid bus reset dm delay: fix a crash when invalid device is specified xfrm: policy: Fix out-of-bound array accesses in __xfrm_policy_unlink xfrm6_tunnel: Fix potential panic when unloading xfrm6_tunnel module vti4: ipip tunnel deregistration fixes. xfrm4: Fix uninitialized memory read in _decode_session4 KVM: arm/arm64: Ensure vcpu target is unset on reset failure power: supply: sysfs: prevent endless uevent loop with CONFIG_POWER_SUPPLY_DEBUG ufs: fix braino in ufs_get_inode_gid() for solaris UFS flavour perf bench numa: Add define for RUSAGE_THREAD if not present Revert "Don't jump to compute_result state from check_result state" md/raid: raid5 preserve the writeback action after the parity check btrfs: Honour FITRIM range constraints during free space trim fbdev: sm712fb: fix memory frequency by avoiding a switch/case fallthrough ext4: do not delete unlinked inode from orphan list on failed truncate KVM: x86: fix return value for reserved EFER bio: fix improper use of smp_mb__before_atomic() Revert "scsi: sd: Keep disk read-only when re-reading partition" crypto: vmx - CTR: always increment IV as quadword gfs2: Fix sign extension bug in gfs2_update_stats Btrfs: fix race between ranged fsync and writeback of adjacent ranges btrfs: sysfs: don't leak memory when failing add fsid fbdev: fix divide error in fb_var_to_videomode hugetlb: use same fault hash key for shared and private mappings fbdev: fix WARNING in __alloc_pages_nodemask bug media: cpia2: Fix use-after-free in cpia2_exit media: vivid: use vfree() instead of kfree() for dev->bitmap_cap ssb: Fix possible NULL pointer dereference in ssb_host_pcmcia_exit at76c50x-usb: Don't register led_trigger if usb_register_driver failed perf tools: No need to include bitops.h in util.h tools include: Adopt linux/bits.h gfs2: Fix lru_count going negative cxgb4: Fix error path in cxgb4_init_module mmc: core: Verify SD bus width powerpc/boot: Fix missing check of lseek() return value ASoC: imx: fix fiq dependencies spi: pxa2xx: fix SCR (divisor) calculation brcm80211: potential NULL dereference in brcmf_cfg80211_vndr_cmds_dcmd_handler() rtc: 88pm860x: prevent use-after-free on device remove w1: fix the resume command API dmaengine: pl330: _stop: clear interrupt status mac80211/cfg80211: update bss channel on channel switch ASoC: fsl_sai: Update is_slave_mode with correct value mwifiex: prevent an array overflow net: cw1200: fix a NULL pointer dereference bcache: return error immediately in bch_journal_replay() bcache: fix failure in journal relplay bcache: add failure check to run_cache_set() for journal replay bcache: avoid clang -Wunintialized warning x86/build: Move _etext to actual end of .text smpboot: Place the __percpu annotation correctly x86/mm: Remove in_nmi() warning from 64-bit implementation of vmalloc_fault() mm/uaccess: Use 'unsigned long' to placate UBSAN warnings on older GCC versions HID: logitech-hidpp: use RAP instead of FAP to get the protocol version pinctrl: pistachio: fix leaked of_node references dmaengine: at_xdmac: remove BUG_ON macro in tasklet media: coda: clear error return value before picture run media: ov6650: Move v4l2_clk_get() to ov6650_video_probe() helper media: au0828: stop video streaming only when last user stops media: ov2659: make S_FMT succeed even if requested format doesn't match audit: fix a memory leak bug media: au0828: Fix NULL pointer dereference in au0828_analog_stream_enable() media: pvrusb2: Prevent a buffer overflow powerpc/numa: improve control of topology updates sched/core: Check quota and period overflow at usec to nsec conversion sched/core: Handle overflow in cpu_shares_write_u64 USB: core: Don't unbind interfaces following device reset failure x86/irq/64: Limit IST stack overflow check to #DB stack i40e: don't allow changes to HW VLAN stripping on active port VLANs RDMA/cxgb4: Fix null pointer dereference on alloc_skb failure hwmon: (vt1211) Use request_muxed_region for Super-IO accesses hwmon: (smsc47m1) Use request_muxed_region for Super-IO accesses hwmon: (smsc47b397) Use request_muxed_region for Super-IO accesses hwmon: (pc87427) Use request_muxed_region for Super-IO accesses hwmon: (f71805f) Use request_muxed_region for Super-IO accesses scsi: libsas: Do discovery on empty PHY to update PHY info mmc_spi: add a status check for spi_sync_locked mmc: sdhci-of-esdhc: add erratum eSDHC5 support mmc: sdhci-of-esdhc: add erratum eSDHC-A001 and A-008358 support PM / core: Propagate dev->power.wakeup_path when no callbacks extcon: arizona: Disable mic detect if running when driver is removed s390: cio: fix cio_irb declaration cpufreq: ppc_cbe: fix possible object reference leak cpufreq/pasemi: fix possible object reference leak cpufreq: pmac32: fix possible object reference leak x86/build: Keep local relocations with ld.lld iio: ad_sigma_delta: Properly handle SPI bus locking vs CS assertion iio: hmc5843: fix potential NULL pointer dereferences iio: common: ssp_sensors: Initialize calculated_time in ssp_common_process_data rtlwifi: fix a potential NULL pointer dereference brcmfmac: fix missing checks for kmemdup b43: shut up clang -Wuninitialized variable warning brcmfmac: convert dev_init_lock mutex to completion brcmfmac: fix race during disconnect when USB completion is in progress scsi: ufs: Fix regulator load and icc-level configuration scsi: ufs: Avoid configuring regulator with undefined voltage range arm64: cpu_ops: fix a leaked reference by adding missing of_node_put x86/ia32: Fix ia32_restore_sigcontext() AC leak chardev: add additional check for minor range overlap HID: core: move Usage Page concatenation to Main item ASoC: eukrea-tlv320: fix a leaked reference by adding missing of_node_put ASoC: fsl_utils: fix a leaked reference by adding missing of_node_put cxgb3/l2t: Fix undefined behaviour spi: tegra114: reset controller on probe media: wl128x: prevent two potential buffer overflows virtio_console: initialize vtermno value for ports tty: ipwireless: fix missing checks for ioremap rcutorture: Fix cleanup path for invalid torture_type strings usb: core: Add PM runtime calls to usb_hcd_platform_shutdown scsi: qla4xxx: avoid freeing unallocated dma memory media: m88ds3103: serialize reset messages in m88ds3103_set_frontend media: go7007: avoid clang frame overflow warning with KASAN media: saa7146: avoid high stack usage with clang scsi: lpfc: Fix SLI3 commands being issued on SLI4 devices spi : spi-topcliff-pch: Fix to handle empty DMA buffers spi: rspi: Fix sequencer reset during initialization spi: Fix zero length xfer bug ASoC: davinci-mcasp: Fix clang warning without CONFIG_PM ipv6: Consider sk_bound_dev_if when binding a raw socket to an address llc: fix skb leak in llc_build_and_send_ui_pkt() net-gro: fix use-after-free read in napi_gro_frags() net: stmmac: fix reset gpio free missing usbnet: fix kernel crash after disconnect tipc: Avoid copying bytes beyond the supplied data bnxt_en: Fix aggregation buffer leak under OOM condition. net: mvpp2: fix bad MVPP2_TXQ_SCHED_TOKEN_CNTR_REG queue value crypto: vmx - ghash: do nosimd fallback manually xen/pciback: Don't disable PCI_COMMAND on PCI device reset. Revert "tipc: fix modprobe tipc failed after switch order of device registration" tipc: fix modprobe tipc failed after switch order of device registration -v2 sparc64: Fix regression in non-hypervisor TLB flush xcall include/linux/bitops.h: sanitize rotate primitives xhci: Convert xhci_handshake() to use readl_poll_timeout_atomic() usb: xhci: avoid null pointer deref when bos field is NULL USB: Fix slab-out-of-bounds write in usb_get_bos_descriptor USB: sisusbvga: fix oops in error path of sisusb_probe USB: Add LPM quirk for Surface Dock GigE adapter USB: rio500: refuse more than one device at a time USB: rio500: fix memory leak in close after disconnect media: usb: siano: Fix general protection fault in smsusb media: usb: siano: Fix false-positive "uninitialized variable" warning media: smsusb: better handle optional alignment scsi: zfcp: fix missing zfcp_port reference put on -EBUSY from port_remove scsi: zfcp: fix to prevent port_remove with pure auto scan LUNs (only sdevs) Btrfs: fix race updating log root item during fsync ALSA: hda/realtek - Set default power save node to 0 drm/nouveau/i2c: Disable i2c bus access after ->fini() tty: serial: msm_serial: Fix XON/XOFF tty: max310x: Fix external crystal register setup memcg: make it work on sparse non-0-node systems kernel/signal.c: trace_signal_deliver when signal_group_exit CIFS: cifs_read_allocate_pages: don't iterate through whole page array on ENOMEM binder: Replace "%p" with "%pK" for stable binder: replace "%p" with "%pK" net: create skb_gso_validate_mac_len() bnx2x: disable GSO where gso_size is too big for hardware brcmfmac: Add length checks on firmware events brcmfmac: screening firmware event packet brcmfmac: revise handling events in receive path brcmfmac: fix incorrect event channel deduction brcmfmac: add length checks in scheduled scan result handler brcmfmac: add subtype check for event handling in data path userfaultfd: don't pin the user memory in userfaultfd_file_create() Revert "x86/build: Move _etext to actual end of .text" net: cdc_ncm: GetNtbFormat endian fix usb: gadget: fix request length error for isoc transfer media: uvcvideo: Fix uvc_alloc_entity() allocation alignment ethtool: fix potential userspace buffer overflow neighbor: Call __ipv4_neigh_lookup_noref in neigh_xmit net/mlx4_en: ethtool, Remove unsupported SFP EEPROM high pages query net: rds: fix memory leak in rds_ib_flush_mr_pool pktgen: do not sleep with the thread lock held. rcu: locking and unlocking need to always be at least barriers parisc: Use implicit space register selection for loading the coherence index of I/O pdirs fuse: fallocate: fix return with locked inode MIPS: pistachio: Build uImage.gz by default genwqe: Prevent an integer overflow in the ioctl drm/gma500/cdv: Check vbt config bits when detecting lvds panels fs: stream_open - opener for stream-like files so that read and write can run simultaneously without deadlock fuse: Add FOPEN_STREAM to use stream_open() ipv4: Define __ipv4_neigh_lookup_noref when CONFIG_INET is disabled ethtool: check the return value of get_regs_len Linux 4.4.181 Change-Id: I0c9e7effbb6bd5d1978b4ffad3db3b76af6692bc Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
| * fs/writeback.c: use rcu_barrier() to wait for inflight wb switches going ↵Jiufei Xue2019-06-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | into workqueue when umount commit ec084de929e419e51bcdafaafe567d9e7d0273b7 upstream. synchronize_rcu() didn't wait for call_rcu() callbacks, so inode wb switch may not go to the workqueue after synchronize_rcu(). Thus previous scheduled switches was not finished even flushing the workqueue, which will cause a NULL pointer dereferenced followed below. VFS: Busy inodes after unmount of vdd. Self-destruct in 5 seconds. Have a nice day... BUG: unable to handle kernel NULL pointer dereference at 0000000000000278 evict+0xb3/0x180 iput+0x1b0/0x230 inode_switch_wbs_work_fn+0x3c0/0x6a0 worker_thread+0x4e/0x490 ? process_one_work+0x410/0x410 kthread+0xe6/0x100 ret_from_fork+0x39/0x50 Replace the synchronize_rcu() call with a rcu_barrier() to wait for all pending callbacks to finish. And inc isw_nr_in_flight after call_rcu() in inode_switch_wbs() to make more sense. Link: http://lkml.kernel.org/r/20190429024108.54150-1-jiufei.xue@linux.alibaba.com Signed-off-by: Jiufei Xue <jiufei.xue@linux.alibaba.com> Acked-by: Tejun Heo <tj@kernel.org> Suggested-by: Tejun Heo <tj@kernel.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * writeback: synchronize sync(2) against cgroup writeback membership switchesTejun Heo2019-06-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 7fc5854f8c6efae9e7624970ab49a1eac2faefb1 upstream. sync_inodes_sb() can race against cgwb (cgroup writeback) membership switches and fail to writeback some inodes. For example, if an inode switches to another wb while sync_inodes_sb() is in progress, the new wb might not be visible to bdi_split_work_to_wbs() at all or the inode might jump from a wb which hasn't issued writebacks yet to one which already has. This patch adds backing_dev_info->wb_switch_rwsem to synchronize cgwb switch path against sync_inodes_sb() so that sync_inodes_sb() is guaranteed to see all the target wbs and inodes can't jump wbs to escape syncing. v2: Fixed misplaced rwsem init. Spotted by Jiufei. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Jiufei Xue <xuejiufei@gmail.com> Link: http://lkml.kernel.org/r/dc694ae2-f07f-61e1-7097-7c8411cee12d@gmail.com Acked-by: Jan Kara <jack@suse.cz> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | Merge 4.4.132 into android-4.4Greg Kroah-Hartman2018-05-16
|\| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Changes in 4.4.132 perf/core: Fix the perf_cpu_time_max_percent check bpf: map_get_next_key to return first key on NULL KVM: s390: Enable all facility bits that are known good for passthrough percpu: include linux/sched.h for cond_resched() mac80211: allow not sending MIC up from driver for HW crypto mac80211: allow same PN for AMSDU sub-frames mac80211: Add RX flag to indicate ICV stripped ath10k: fix rfc1042 header retrieval in QCA4019 with eth decap mode ath10k: rebuild crypto header in rx data frames gpmi-nand: Handle ECC Errors in erased pages USB: serial: option: Add support for Quectel EP06 ALSA: pcm: Check PCM state at xfern compat ioctl ALSA: seq: Fix races at MIDI encoding in snd_virmidi_output_trigger() ALSA: aloop: Mark paused device as inactive ALSA: aloop: Add missing cable lock to ctl API callbacks tracepoint: Do not warn on ENOMEM Input: leds - fix out of bound access Input: atmel_mxt_ts - add touchpad button mapping for Samsung Chromebook Pro xfs: prevent creating negative-sized file via INSERT_RANGE RDMA/ucma: Allow resolving address w/o specifying source address RDMA/mlx5: Protect from shift operand overflow NET: usb: qmi_wwan: add support for ublox R410M PID 0x90b2 IB/mlx5: Use unlimited rate when static rate is not supported drm/vmwgfx: Fix a buffer object leak test_firmware: fix setting old custom fw path back on exit, second try USB: serial: visor: handle potential invalid device configuration USB: Accept bulk endpoints with 1024-byte maxpacket USB: serial: option: reimplement interface masking USB: serial: option: adding support for ublox R410M usb: musb: host: fix potential NULL pointer dereference ipvs: fix rtnl_lock lockups caused by start_sync_thread crypto: af_alg - fix possible uninit-value in alg_bind() netlink: fix uninit-value in netlink_sendmsg net: fix rtnh_ok() net: initialize skb->peeked when cloning net: fix uninit-value in __hw_addr_add_ex() dccp: initialize ireq->ir_mark soreuseport: initialise timewait reuseport field perf: Remove superfluous allocation error check tcp: fix TCP_REPAIR_QUEUE bound checking bdi: Fix oops in wb_workfn() f2fs: fix a dead loop in f2fs_fiemap() xfrm_user: fix return value from xfrm_user_rcv_msg rfkill: gpio: fix memory leak in probe error path libata: Apply NOLPM quirk for SanDisk SD7UB3Q*G1001 SSDs tracing: Fix regex_match_front() to not over compare the test string can: kvaser_usb: Increase correct stats counter in kvaser_usb_rx_can_msg() net: atm: Fix potential Spectre v1 atm: zatm: Fix potential Spectre v1 Revert "Bluetooth: btusb: Fix quirk for Atheros 1525/QCA6174" tracing/uprobe_event: Fix strncpy corner case perf/x86: Fix possible Spectre-v1 indexing for hw_perf_event cache_* perf/x86/cstate: Fix possible Spectre-v1 indexing for pkg_msr perf/x86/msr: Fix possible Spectre-v1 indexing in the MSR driver perf/core: Fix possible Spectre-v1 indexing for ->aux_pages[] perf/x86: Fix possible Spectre-v1 indexing for x86_pmu::event_map() Linux 4.4.132 Change-Id: I66c21e374dff5a5735f1c5958021612387c635bf Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
| * bdi: Fix oops in wb_workfn()Jan Kara2018-05-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit b8b784958eccbf8f51ebeee65282ca3fd59ea391 upstream. Syzbot has reported that it can hit a NULL pointer dereference in wb_workfn() due to wb->bdi->dev being NULL. This indicates that wb_workfn() was called for an already unregistered bdi which should not happen as wb_shutdown() called from bdi_unregister() should make sure all pending writeback works are completed before bdi is unregistered. Except that wb_workfn() itself can requeue the work with: mod_delayed_work(bdi_wq, &wb->dwork, 0); and if this happens while wb_shutdown() is waiting in: flush_delayed_work(&wb->dwork); the dwork can get executed after wb_shutdown() has finished and bdi_unregister() has cleared wb->bdi->dev. Make wb_workfn() use wakeup_wb() for requeueing the work which takes all the necessary precautions against racing with bdi unregistration. CC: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> CC: Tejun Heo <tj@kernel.org> Fixes: 839a8e8660b6777e7fe4e80af1a048aebe2b5977 Reported-by: syzbot <syzbot+9873874c735f2892e7e9@syzkaller.appspotmail.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | Merge 4.4.129 into android-4.4Greg Kroah-Hartman2018-04-24
|\| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Changes in 4.4.129 media: v4l2-compat-ioctl32: don't oops on overlay parisc: Fix out of array access in match_pci_device() perf intel-pt: Fix overlap detection to identify consecutive buffers correctly perf intel-pt: Fix sync_switch perf intel-pt: Fix error recovery from missing TIP packet perf intel-pt: Fix timestamp following overflow radeon: hide pointless #warning when compile testing Revert "perf tests: Decompress kernel module before objdump" block/loop: fix deadlock after loop_set_status s390/qdio: don't retry EQBS after CCQ 96 s390/qdio: don't merge ERROR output buffers s390/ipl: ensure loadparm valid flag is set getname_kernel() needs to make sure that ->name != ->iname in long case rtl8187: Fix NULL pointer dereference in priv->conf_mutex hwmon: (ina2xx) Fix access to uninitialized mutex cdc_ether: flag the Cinterion AHS8 modem by gemalto as WWAN slip: Check if rstate is initialized before uncompressing lan78xx: Correctly indicate invalid OTP x86/hweight: Get rid of the special calling convention x86/hweight: Don't clobber %rdi tty: make n_tty_read() always abort if hangup is in progress ubifs: Check ubifs_wbuf_sync() return code ubi: fastmap: Don't flush fastmap work on detach ubi: Fix error for write access ubi: Reject MLC NAND fs/reiserfs/journal.c: add missing resierfs_warning() arg resource: fix integer overflow at reallocation ipc/shm: fix use-after-free of shm file via remap_file_pages() mm, slab: reschedule cache_reap() on the same CPU usb: musb: gadget: misplaced out of bounds check ARM: dts: at91: at91sam9g25: fix mux-mask pinctrl property ARM: dts: at91: sama5d4: fix pinctrl compatible string xen-netfront: Fix hang on device removal regmap: Fix reversed bounds check in regmap_raw_write() ACPI / video: Add quirk to force acpi-video backlight on Samsung 670Z5E ACPI / hotplug / PCI: Check presence of slot itself in get_slot_status() USB:fix USB3 devices behind USB3 hubs not resuming at hibernate thaw usb: dwc3: pci: Properly cleanup resource HID: i2c-hid: fix size check and type usage powerpc/powernv: Handle unknown OPAL errors in opal_nvram_write() powerpc/64: Fix smp_wmb barrier definition use use lwsync consistently powerpc/powernv: define a standard delay for OPAL_BUSY type retry loops powerpc/powernv: Fix OPAL NVRAM driver OPAL_BUSY loops HID: Fix hid_report_len usage HID: core: Fix size as type u32 ASoC: ssm2602: Replace reg_default_raw with reg_default thunderbolt: Resume control channel after hibernation image is created random: use a tighter cap in credit_entropy_bits_safe() jbd2: if the journal is aborted then don't allow update of the log tail ext4: don't update checksum of new initialized bitmaps ext4: fail ext4_iget for root directory if unallocated RDMA/ucma: Don't allow setting RDMA_OPTION_IB_PATH without an RDMA device ALSA: pcm: Fix UAF at PCM release via PCM timer access IB/srp: Fix srp_abort() IB/srp: Fix completion vector assignment algorithm dmaengine: at_xdmac: fix rare residue corruption um: Use POSIX ucontext_t instead of struct ucontext iommu/vt-d: Fix a potential memory leak mmc: jz4740: Fix race condition in IRQ mask update clk: mvebu: armada-38x: add support for 1866MHz variants clk: mvebu: armada-38x: add support for missing clocks clk: bcm2835: De-assert/assert PLL reset signal when appropriate thermal: imx: Fix race condition in imx_thermal_probe() watchdog: f71808e_wdt: Fix WD_EN register read ALSA: oss: consolidate kmalloc/memset 0 call to kzalloc ALSA: pcm: Use ERESTARTSYS instead of EINTR in OSS emulation ALSA: pcm: Avoid potential races between OSS ioctls and read/write ALSA: pcm: Return -EBUSY for OSS ioctls changing busy streams ALSA: pcm: Fix mutex unbalance in OSS emulation ioctls ALSA: pcm: Fix endless loop for XRUN recovery in OSS emulation vfio-pci: Virtualize PCIe & AF FLR vfio/pci: Virtualize Maximum Payload Size vfio/pci: Virtualize Maximum Read Request Size ext4: don't allow r/w mounts if metadata blocks overlap the superblock drm/radeon: Fix PCIe lane width calculation ext4: fix crashes in dioread_nolock mode ext4: fix deadlock between inline_data and ext4_expand_extra_isize_ea() ALSA: line6: Use correct endpoint type for midi output ALSA: rawmidi: Fix missing input substream checks in compat ioctls ALSA: hda - New VIA controller suppor no-snoop path HID: hidraw: Fix crash on HIDIOCGFEATURE with a destroyed device MIPS: uaccess: Add micromips clobbers to bzero invocation MIPS: memset.S: EVA & fault support for small_memset MIPS: memset.S: Fix return of __clear_user from Lpartial_fixup MIPS: memset.S: Fix clobber of v1 in last_fixup powerpc/eeh: Fix enabling bridge MMIO windows powerpc/lib: Fix off-by-one in alternate feature patching jffs2_kill_sb(): deal with failed allocations hypfs_kill_super(): deal with failed allocations rpc_pipefs: fix double-dput() Don't leak MNT_INTERNAL away from internal mounts autofs: mount point create should honour passed in mode mm: allow GFP_{FS,IO} for page_cache_read page cache allocation mm/filemap.c: fix NULL pointer in page_cache_tree_insert() ext4: bugfix for mmaped pages in mpage_release_unused_pages() fanotify: fix logic of events on child writeback: safer lock nesting Linux 4.4.129 Change-Id: I8806d2cc92fe512f27a349e8f630ced0cac9a8d7 Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
| * writeback: safer lock nestingGreg Thelen2018-04-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 2e898e4c0a3897ccd434adac5abb8330194f527b upstream. lock_page_memcg()/unlock_page_memcg() use spin_lock_irqsave/restore() if the page's memcg is undergoing move accounting, which occurs when a process leaves its memcg for a new one that has memory.move_charge_at_immigrate set. unlocked_inode_to_wb_begin,end() use spin_lock_irq/spin_unlock_irq() if the given inode is switching writeback domains. Switches occur when enough writes are issued from a new domain. This existing pattern is thus suspicious: lock_page_memcg(page); unlocked_inode_to_wb_begin(inode, &locked); ... unlocked_inode_to_wb_end(inode, locked); unlock_page_memcg(page); If both inode switch and process memcg migration are both in-flight then unlocked_inode_to_wb_end() will unconditionally enable interrupts while still holding the lock_page_memcg() irq spinlock. This suggests the possibility of deadlock if an interrupt occurs before unlock_page_memcg(). truncate __cancel_dirty_page lock_page_memcg unlocked_inode_to_wb_begin unlocked_inode_to_wb_end <interrupts mistakenly enabled> <interrupt> end_page_writeback test_clear_page_writeback lock_page_memcg <deadlock> unlock_page_memcg Due to configuration limitations this deadlock is not currently possible because we don't mix cgroup writeback (a cgroupv2 feature) and memory.move_charge_at_immigrate (a cgroupv1 feature). If the kernel is hacked to always claim inode switching and memcg moving_account, then this script triggers lockup in less than a minute: cd /mnt/cgroup/memory mkdir a b echo 1 > a/memory.move_charge_at_immigrate echo 1 > b/memory.move_charge_at_immigrate ( echo $BASHPID > a/cgroup.procs while true; do dd if=/dev/zero of=/mnt/big bs=1M count=256 done ) & while true; do sync done & sleep 1h & SLEEP=$! while true; do echo $SLEEP > a/cgroup.procs echo $SLEEP > b/cgroup.procs done The deadlock does not seem possible, so it's debatable if there's any reason to modify the kernel. I suggest we should to prevent future surprises. And Wang Long said "this deadlock occurs three times in our environment", so there's more reason to apply this, even to stable. Stable 4.4 has minor conflicts applying this patch. For a clean 4.4 patch see "[PATCH for-4.4] writeback: safer lock nesting" https://lkml.org/lkml/2018/4/11/146 Wang Long said "this deadlock occurs three times in our environment" [gthelen@google.com: v4] Link: http://lkml.kernel.org/r/20180411084653.254724-1-gthelen@google.com [akpm@linux-foundation.org: comment tweaks, struct initialization simplification] Change-Id: Ibb773e8045852978f6207074491d262f1b3fb613 Link: http://lkml.kernel.org/r/20180410005908.167976-1-gthelen@google.com Fixes: 682aa8e1a6a1 ("writeback: implement unlocked_inode_to_wb transaction and use it for stat updates") Signed-off-by: Greg Thelen <gthelen@google.com> Reported-by: Wang Long <wanglong19@meituan.com> Acked-by: Wang Long <wanglong19@meituan.com> Acked-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Tejun Heo <tj@kernel.org> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: <stable@vger.kernel.org> [v4.2+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> [natechancellor: Applied to 4.4 based on Greg's backport on lkml.org] Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | Merge 4.4.107 into android-4.4Greg Kroah-Hartman2017-12-20
|\| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Changes in 4.4.107 crypto: hmac - require that the underlying hash algorithm is unkeyed crypto: salsa20 - fix blkcipher_walk API usage autofs: fix careless error in recent commit tracing: Allocate mask_str buffer dynamically USB: uas and storage: Add US_FL_BROKEN_FUA for another JMicron JMS567 ID USB: core: prevent malicious bNumInterfaces overflow usbip: fix stub_send_ret_submit() vulnerability to null transfer_buffer ceph: drop negative child dentries before try pruning inode's alias Bluetooth: btusb: driver to enable the usb-wakeup feature xhci: Don't add a virt_dev to the devs array before it's fully allocated sched/rt: Do not pull from current CPU if only one CPU to pull dmaengine: dmatest: move callback wait queue to thread context ext4: fix fdatasync(2) after fallocate(2) operation ext4: fix crash when a directory's i_size is too small KEYS: add missing permission check for request_key() destination mac80211: Fix addition of mesh configuration element usb: phy: isp1301: Add OF device ID table md-cluster: free md_cluster_info if node leave cluster userfaultfd: shmem: __do_fault requires VM_FAULT_NOPAGE userfaultfd: selftest: vm: allow to build in vm/ directory net: initialize msg.msg_flags in recvfrom net: bcmgenet: correct the RBUF_OVFL_CNT and RBUF_ERR_CNT MIB values net: bcmgenet: correct MIB access of UniMAC RUNT counters net: bcmgenet: reserved phy revisions must be checked first net: bcmgenet: power down internal phy if open or resume fails net: bcmgenet: Power up the internal PHY before probing the MII NFSD: fix nfsd_minorversion(.., NFSD_AVAIL) NFSD: fix nfsd_reset_versions for NFSv4. Input: i8042 - add TUXEDO BU1406 (N24_25BU) to the nomux list drm/omap: fix dmabuf mmap for dma_alloc'ed buffers netfilter: bridge: honor frag_max_size when refragmenting writeback: fix memory leak in wb_queue_work() net: wimax/i2400m: fix NULL-deref at probe dmaengine: Fix array index out of bounds warning in __get_unmap_pool() net: Resend IGMP memberships upon peer notification. mlxsw: reg: Fix SPVM max record count mlxsw: reg: Fix SPVMLR max record count intel_th: pci: Add Gemini Lake support openrisc: fix issue handling 8 byte get_user calls scsi: hpsa: update check for logical volume status scsi: hpsa: limit outstanding rescans fjes: Fix wrong netdevice feature flags drm/radeon/si: add dpm quirk for Oland sched/deadline: Make sure the replenishment timer fires in the next period sched/deadline: Throttle a constrained deadline task activated after the deadline sched/deadline: Use deadline instead of period when calculating overflow mmc: mediatek: Fixed bug where clock frequency could be set wrong drm/radeon: reinstate oland workaround for sclk afs: Fix missing put_page() afs: Populate group ID from vnode status afs: Adjust mode bits processing afs: Flush outstanding writes when an fd is closed afs: Migrate vlocation fields to 64-bit afs: Prevent callback expiry timer overflow afs: Fix the maths in afs_fs_store_data() afs: Populate and use client modification time afs: Fix page leak in afs_write_begin() afs: Fix afs_kill_pages() net/mlx4_core: Avoid delays during VF driver device shutdown perf symbols: Fix symbols__fixup_end heuristic for corner cases efi/esrt: Cleanup bad memory map log messages NFSv4.1 respect server's max size in CREATE_SESSION btrfs: add missing memset while reading compressed inline extents target: Use system workqueue for ALUA transitions target: fix ALUA transition timeout handling target: fix race during implicit transition work flushes sfc: don't warn on successful change of MAC fbdev: controlfb: Add missing modes to fix out of bounds access video: udlfb: Fix read EDID timeout video: fbdev: au1200fb: Release some resources if a memory allocation fails video: fbdev: au1200fb: Return an error code if a memory allocation fails rtc: pcf8563: fix output clock rate dmaengine: ti-dma-crossbar: Correct am335x/am43xx mux value type PCI/PME: Handle invalid data when reading Root Status powerpc/powernv/cpufreq: Fix the frequency read by /proc/cpuinfo netfilter: ipvs: Fix inappropriate output of procfs powerpc/opal: Fix EBUSY bug in acquiring tokens powerpc/ipic: Fix status get and status clear target/iscsi: Fix a race condition in iscsit_add_reject_from_cmd() iscsi-target: fix memory leak in lio_target_tiqn_addtpg() target:fix condition return in core_pr_dump_initiator_port() target/file: Do not return error for UNMAP if length is zero arm-ccn: perf: Prevent module unload while PMU is in use crypto: tcrypt - fix buffer lengths in test_aead_speed() mm: Handle 0 flags in _calc_vm_trans() macro clk: mediatek: add the option for determining PLL source clock clk: imx6: refine hdmi_isfr's parent to make HDMI work on i.MX6 SoCs w/o VPU clk: tegra: Fix cclk_lp divisor register ppp: Destroy the mutex when cleanup thermal/drivers/step_wise: Fix temperature regulation misbehavior GFS2: Take inode off order_write list when setting jdata flag bcache: explicitly destroy mutex while exiting bcache: fix wrong cache_misses statistics l2tp: cleanup l2tp_tunnel_delete calls xfs: fix log block underflow during recovery cycle verification xfs: fix incorrect extent state in xfs_bmap_add_extent_unwritten_real PCI: Detach driver before procfs & sysfs teardown on device remove scsi: hpsa: cleanup sas_phy structures in sysfs when unloading scsi: hpsa: destroy sas transport properties before scsi_host powerpc/perf/hv-24x7: Fix incorrect comparison in memord tty fix oops when rmmod 8250 usb: musb: da8xx: fix babble condition handling pinctrl: adi2: Fix Kconfig build problem raid5: Set R5_Expanded on parity devices as well as data. scsi: scsi_devinfo: Add REPORTLUN2 to EMC SYMMETRIX blacklist entry vt6655: Fix a possible sleep-in-atomic bug in vt6655_suspend scsi: sd: change manage_start_stop to bool in sysfs interface scsi: sd: change allow_restart to bool in sysfs interface scsi: bfa: integer overflow in debugfs udf: Avoid overflow when session starts at large offset macvlan: Only deliver one copy of the frame to the macvlan interface RDMA/cma: Avoid triggering undefined behavior IB/ipoib: Grab rtnl lock on heavy flush when calling ndo_open/stop ath9k: fix tx99 potential info leak Linux 4.4.107 Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
| * writeback: fix memory leak in wb_queue_work()Tahsin Erdogan2017-12-20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit 4a3a485b1ed0e109718cc8c9d094fa0f552de9b2 ] When WB_registered flag is not set, wb_queue_work() skips queuing the work, but does not perform the necessary clean up. In particular, if work->auto_free is true, it should free the memory. The leak condition can be reprouced by following these steps: mount /dev/sdb /mnt/sdb /* In qemu console: device_del sdb */ umount /dev/sdb Above will result in a wb_queue_work() call on an unregistered wb and thus leak memory. Reported-by: John Sperbeck <jsperbeck@google.com> Signed-off-by: Tahsin Erdogan <tahsin@google.com> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Jens Axboe <axboe@fb.com> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | Merge tag 'v4.4.16' into android-4.4.yDmitry Shmidt2016-08-01
|\| | | | | | | | | | | This is the 4.4.16 stable release Change-Id: Ibaf7b7e03695e1acebc654a2ca1a4bfcc48fcea4
| * writeback, cgroup: fix use of the wrong bdi_writeback which mismatches the inodeTejun Heo2016-04-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit aaf2559332ba272671bb870464a99b909b29a3a1 upstream. When cgroup writeback is in use, there can be multiple wb's (bdi_writeback's) per bdi and an inode may switch among them dynamically. In a couple places, the wrong wb was used leading to performing operations on the wrong list under the wrong lock corrupting the io lists. * writeback_single_inode() was taking @wb parameter and used it to remove the inode from io lists if it becomes clean after writeback. The callers of this function were always passing in the root wb regardless of the actual wb that the inode was associated with, which could also change while writeback is in progress. Fix it by dropping the @wb parameter and using inode_to_wb_and_lock_list() to determine and lock the associated wb. * After writeback_sb_inodes() writes out an inode, it re-locks @wb and inode to remove it from or move it to the right io list. It assumes that the inode is still associated with @wb; however, the inode may have switched to another wb while writeback was in progress. Fix it by using inode_to_wb_and_lock_list() to determine and lock the associated wb after writeback is complete. As the function requires the original @wb->list_lock locked for the next iteration, in the unlikely case where the inode has changed association, switch the locks. Kudos to Tahsin for pinpointing these subtle breakages. Signed-off-by: Tejun Heo <tj@kernel.org> Fixes: d10c80955265 ("writeback: implement foreign cgroup inode bdi_writeback switching") Link: http://lkml.kernel.org/g/CAAeU0aMYeM_39Y2+PaRvyB1nqAPYZSNngJ1eBRmrxn7gKAt2Mg@mail.gmail.com Reported-and-diagnosed-by: Tahsin Erdogan <tahsin@google.com> Tested-by: Tahsin Erdogan <tahsin@google.com> Signed-off-by: Jens Axboe <axboe@fb.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * writeback, cgroup: fix premature wb_put() in locked_inode_to_wb_and_lock_list()Tejun Heo2016-04-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 614a4e3773148a31f58dc174bbf578ceb63510c2 upstream. locked_inode_to_wb_and_lock_list() wb_get()'s the wb associated with the target inode, unlocks inode, locks the wb's list_lock and verifies that the inode is still associated with the wb. To prevent the wb going away between dropping inode lock and acquiring list_lock, the wb is pinned while inode lock is held. The wb reference is put right after acquiring list_lock citing that the wb won't be dereferenced anymore. This isn't true. If the inode is still associated with the wb, the inode has reference and it's safe to return the wb; however, if inode has been switched, the wb still needs to be unlocked which is a dereference and can lead to use-after-free if it it races with wb destruction. Fix it by putting the reference after releasing list_lock. Signed-off-by: Tejun Heo <tj@kernel.org> Fixes: 87e1d789bf55 ("writeback: implement [locked_]inode_to_wb_and_lock_list()") Tested-by: Tahsin Erdogan <tahsin@google.com> Signed-off-by: Jens Axboe <axboe@fb.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * writeback: flush inode cgroup wb switches instead of pinning super_blockTejun Heo2016-03-09
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit a1a0e23e49037c23ea84bc8cc146a03584d13577 upstream. If cgroup writeback is in use, inodes can be scheduled for asynchronous wb switching. Before 5ff8eaac1636 ("writeback: keep superblock pinned during cgroup writeback association switches"), this could race with umount leading to super_block being destroyed while inodes are pinned for wb switching. 5ff8eaac1636 fixed it by bumping s_active while wb switches are in flight; however, this allowed in-flight wb switches to make umounts asynchronous when the userland expected synchronosity - e.g. fsck immediately following umount may fail because the device is still busy. This patch removes the problematic super_block pinning and instead makes generic_shutdown_super() flush in-flight wb switches. wb switches are now executed on a dedicated isw_wq so that they can be flushed and isw_nr_in_flight keeps track of the number of in-flight wb switches so that flushing can be avoided in most cases. v2: Move cgroup_writeback_umount() further below and add MS_ACTIVE check in inode_switch_wbs() as Jan an Al suggested. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Tahsin Erdogan <tahsin@google.com> Cc: Jan Kara <jack@suse.cz> Cc: Al Viro <viro@ZenIV.linux.org.uk> Link: http://lkml.kernel.org/g/CAAeU0aNCq7LGODvVGRU-oU_o-6enii5ey0p1c26D1ZzYwkDc5A@mail.gmail.com Fixes: 5ff8eaac1636 ("writeback: keep superblock pinned during cgroup writeback association switches") Reviewed-by: Jan Kara <jack@suse.cz> Tested-by: Tahsin Erdogan <tahsin@google.com> Signed-off-by: Jens Axboe <axboe@fb.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * writeback: keep superblock pinned during cgroup writeback association switchesTejun Heo2016-03-03
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 5ff8eaac1636bf6deae86491f4818c4c69d1a9ac upstream. If cgroup writeback is in use, an inode is associated with a cgroup for writeback. If the inode's main dirtier changes to another cgroup, the association gets updated asynchronously. Nothing was pinning the superblock while such switches are in progress and superblock could go away while async switching is pending or in progress leading to crashes like the following. kernel BUG at fs/jbd2/transaction.c:319! invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC CPU: 1 PID: 29158 Comm: kworker/1:10 Not tainted 4.5.0-rc3 #51 Hardware name: Google Google, BIOS Google 01/01/2011 Workqueue: events inode_switch_wbs_work_fn task: ffff880213dbbd40 ti: ffff880209264000 task.ti: ffff880209264000 RIP: 0010:[<ffffffff803e6922>] [<ffffffff803e6922>] start_this_handle+0x382/0x3e0 RSP: 0018:ffff880209267c30 EFLAGS: 00010202 ... Call Trace: [<ffffffff803e6be4>] jbd2__journal_start+0xf4/0x190 [<ffffffff803cfc7e>] __ext4_journal_start_sb+0x4e/0x70 [<ffffffff803b31ec>] ext4_evict_inode+0x12c/0x3d0 [<ffffffff8035338b>] evict+0xbb/0x190 [<ffffffff80354190>] iput+0x130/0x190 [<ffffffff80360223>] inode_switch_wbs_work_fn+0x343/0x4c0 [<ffffffff80279819>] process_one_work+0x129/0x300 [<ffffffff80279b16>] worker_thread+0x126/0x480 [<ffffffff8027ed14>] kthread+0xc4/0xe0 [<ffffffff809771df>] ret_from_fork+0x3f/0x70 Fix it by bumping s_active while cgroup association switching is in flight. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-and-tested-by: Tahsin Erdogan <tahsin@google.com> Link: http://lkml.kernel.org/g/CAAeU0aNCq7LGODvVGRU-oU_o-6enii5ey0p1c26D1ZzYwkDc5A@mail.gmail.com Fixes: d10c80955265 ("writeback: implement foreign cgroup inode bdi_writeback switching") Signed-off-by: Jens Axboe <axboe@fb.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | fs: block_dump: Don't display inode changes if block_dump < 2San Mehat2016-02-16
|/ | | | Signed-off-by: San Mehat <san@android.com>
* fs/writeback.c: fix kernel-doc warningsRandy Dunlap2015-11-09
| | | | | | | | | | | | | | Fix kernel-doc warnings in fs/fs-writeback.c by moving a #define macro to after the function's opening brace. Also #undef this macro at the end of the function. ../fs/fs-writeback.c:1984: warning: Excess function parameter 'inode' description in 'I_DIRTY_INODE' ../fs/fs-writeback.c:1984: warning: Excess function parameter 'flags' description in 'I_DIRTY_INODE' Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/filemap.c: make global sync not clear error status of individual inodesJunichi Nomura2015-11-05
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | filemap_fdatawait() is a function to wait for on-going writeback to complete but also consume and clear error status of the mapping set during writeback. The latter functionality is critical for applications to detect writeback error with system calls like fsync(2)/fdatasync(2). However filemap_fdatawait() is also used by sync(2) or FIFREEZE ioctl, which don't check error status of individual mappings. As a result, fsync() may not be able to detect writeback error if events happen in the following order: Application System admin ---------------------------------------------------------- write data on page cache Run sync command writeback completes with error filemap_fdatawait() clears error fsync returns success (but the data is not on disk) This patch adds filemap_fdatawait_keep_errors() for call sites where writeback error is not handled so that they don't clear error status. Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com> Acked-by: Andi Kleen <ak@linux.intel.com> Reviewed-by: Tejun Heo <tj@kernel.org> Cc: Fengguang Wu <fengguang.wu@gmail.com> Cc: Dave Chinner <david@fromorbit.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* fs/writeback, rcu: Don't use list_entry_rcu() for pointer offsetting in ↵Tejun Heo2015-10-28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | bdi_split_work_to_wbs() bdi_split_work_to_wbs() uses list_for_each_entry_rcu_continue() to walk @bdi->wb_list. To set up the initial iteration condition, it uses list_entry_rcu() to calculate the entry pointer corresponding to the list head; however, this isn't an actual RCU dereference and using list_entry_rcu() for it ended up breaking a proposed list_entry_rcu() change because it was feeding an non-lvalue pointer into the macro. Don't use the RCU variant for simple pointer offsetting. Use list_entry() instead. Reported-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Darren Hart <dvhart@linux.intel.com> Cc: David Howells <dhowells@redhat.com> Cc: Dipankar Sarma <dipankar@in.ibm.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Josh Triplett <josh@joshtriplett.org> Cc: Lai Jiangshan <jiangshanlai@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Patrick Marlier <patrick.marlier@gmail.com> Cc: Paul McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: pranith kumar <bobby.prani@gmail.com> Link: http://lkml.kernel.org/r/20151027051939.GA19355@mtj.duckdns.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* writeback: bdi_writeback iteration must not skip dying onesTejun Heo2015-10-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | bdi_for_each_wb() is used in several places to wake up or issue writeback work items to all wb's (bdi_writeback's) on a given bdi. The iteration is performed by walking bdi->cgwb_tree; however, the tree only indexes wb's which are currently active. For example, when a memcg gets associated with a different blkcg, the old wb is removed from the tree so that the new one can be indexed. The old wb starts dying from then on but will linger till all its inodes are drained. As these dying wb's may still host dirty inodes, writeback operations which affect all wb's must include them. bdi_for_each_wb() skipping dying wb's led to sync(2) missing and failing to sync the inodes belonging to those wb's. This patch adds a RCU protected @bdi->wb_list which lists all wb's beloinging to that bdi. wb's are added on creation and removed on release rather than on the start of destruction. bdi_for_each_wb() usages are replaced with list_for_each[_continue]_rcu() iterations over @bdi->wb_list and bdi_for_each_wb() and its helpers are removed. v2: Updated as per Jan. last_wb ref leak in bdi_split_work_to_wbs() fixed and unnecessary list head severing in cgwb_bdi_destroy() removed. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-and-tested-by: Artem Bityutskiy <dedekind1@gmail.com> Fixes: ebe41ab0c79d ("writeback: implement bdi_for_each_wb()") Link: http://lkml.kernel.org/g/1443012552.19983.209.camel@gmail.com Cc: Jan Kara <jack@suse.cz> Signed-off-by: Jens Axboe <axboe@fb.com>
* writeback: fix bdi_writeback iteration in wakeup_dirtytime_writeback()Tejun Heo2015-10-12
| | | | | | | | | | | wakeup_dirtytime_writeback() walks and wakes up all wb's of all bdi's; unfortunately, it was always waking up bdi->wb instead of the wb being walked. Fix it. Signed-off-by: Tejun Heo <tj@kernel.org> Fixes: 001fe6f617b1 ("writeback: make wakeup_dirtytime_writeback() handle multiple bdi_writeback's") Reviewed-by: Jan Kara <jack@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>
* fs-writeback: unplug before cond_resched in writeback_sb_inodesChris Mason2015-09-19
| | | | | | | | | | | | | | | | | | | | | | | Commit 505a666ee3fc ("writeback: plug writeback in wb_writeback() and writeback_inodes_wb()") has us holding a plug during writeback_sb_inodes, which increases the merge rate when relatively contiguous small files are written by the filesystem. It helps both on flash and spindles. For an fs_mark workload creating 4K files in parallel across 8 drives, this commit improves performance ~9% more by unplugging before calling cond_resched(). cond_resched() doesn't trigger an implicit unplug, so explicitly getting the IO down to the device before scheduling reduces latencies for anyone waiting on clean pages. It also cuts down on how often we use kblockd to unplug, which means less work bouncing from one workqueue to another. Many more details about how we got here: https://lkml.org/lkml/2015/9/11/570 Signed-off-by: Chris Mason <clm@fb.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* writeback: plug writeback in wb_writeback() and writeback_inodes_wb()Linus Torvalds2015-09-12
| | | | | | | | | | | | | | | | | | | | | | | | | We had to revert the pluggin in writeback_sb_inodes() because the wb->list_lock is held, but we could easily plug at a higher level before taking that lock, and unplug after releasing it. This does that. Chris will run performance numbers, just to verify that this approach is comparable to the alternative (we could just drop and re-take the lock around the blk_finish_plug() rather than these two commits. I'd have preferred waiting for actual performance numbers before picking one approach over the other, but I don't want to release rc1 with the known "sleeping function called from invalid context" issue, so I'll pick this cleanup version for now. But if the numbers show that we really want to plug just at the writeback_sb_inodes() level, and we should just play ugly games with the spinlock, we'll switch to that. Cc: Chris Mason <clm@fb.com> Cc: Josef Bacik <jbacik@fb.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Neil Brown <neilb@suse.de> Cc: Jan Kara <jack@suse.cz> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Revert "writeback: plug writeback at a high level"Linus Torvalds2015-09-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This reverts commit d353d7587d02116b9732d5c06615aed75a4d3a47. Doing the block layer plug/unplug inside writeback_sb_inodes() is broken, because that function is actually called with a spinlock held: wb->list_lock, as pointed out by Chris Mason. Chris suggested just dropping and re-taking the spinlock around the blk_finish_plug() call (the plgging itself can happen under the spinlock), and that would technically work, but is just disgusting. We do something fairly similar - but not quite as disgusting because we at least have a better reason for it - in writeback_single_inode(), so it's not like the caller can depend on the lock being held over the call, but in this case there just isn't any good reason for that "release and re-take the lock" pattern. [ In general, we should really strive to avoid the "release and retake" pattern for locks, because in the general case it can easily cause subtle bugs when the caller caches any state around the call that might be invalidated by dropping the lock even just temporarily. ] But in this case, the plugging should be easy to just move up to the callers before the spinlock is taken, which should even improve the effectiveness of the plug. So there is really no good reason to play games with locking here. I'll send off a test-patch so that Dave Chinner can verify that that plug movement works. In the meantime this just reverts the problematic commit and adds a comment to the function so that we hopefully don't make this mistake again. Reported-by: Chris Mason <clm@fb.com> Cc: Josef Bacik <jbacik@fb.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Neil Brown <neilb@suse.de> Cc: Jan Kara <jack@suse.cz> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'for-4.3/blkcg' of git://git.kernel.dk/linux-blockLinus Torvalds2015-09-10
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull blk-cg updates from Jens Axboe: "A bit later in the cycle, but this has been in the block tree for a a while. This is basically four patchsets from Tejun, that improve our buffered cgroup writeback. It was dependent on the other cgroup changes, but they went in earlier in this cycle. Series 1 is set of 5 patches that has cgroup writeback updates: - bdi_writeback iteration fix which could lead to some wb's being skipped or repeated during e.g. sync under memory pressure. - Simplification of wb work wait mechanism. - Writeback tracepoints updated to report cgroup. Series 2 is is a set of updates for the CFQ cgroup writeback handling: cfq has always charged all async IOs to the root cgroup. It didn't have much choice as writeback didn't know about cgroups and there was no way to tell who to blame for a given writeback IO. writeback finally grew support for cgroups and now tags each writeback IO with the appropriate cgroup to charge it against. This patchset updates cfq so that it follows the blkcg each bio is tagged with. Async cfq_queues are now shared across cfq_group, which is per-cgroup, instead of per-request_queue cfq_data. This makes all IOs follow the weight based IO resource distribution implemented by cfq. - Switched from GFP_ATOMIC to GFP_NOWAIT as suggested by Jeff. - Other misc review points addressed, acks added and rebased. Series 3 is the blkcg policy cleanup patches: This patchset contains assorted cleanups for blkcg_policy methods and blk[c]g_policy_data handling. - alloc/free added for blkg_policy_data. exit dropped. - alloc/free added for blkcg_policy_data. - blk-throttle's async percpu allocation is replaced with direct allocation. - all methods now take blk[c]g_policy_data instead of blkcg_gq or blkcg. And finally, series 4 is a set of patches cleaning up the blkcg stats handling: blkcg's stats have always been somwhat of a mess. This patchset tries to improve the situation a bit. - The following patches added to consolidate blkcg entry point and blkg creation. This is in itself is an improvement and helps colllecting common stats on bio issue. - per-blkg stats now accounted on bio issue rather than request completion so that bio based and request based drivers can behave the same way. The issue was spotted by Vivek. - cfq-iosched implements custom recursive stats and blk-throttle implements custom per-cpu stats. This patchset make blkcg core support both by default. - cfq-iosched and blk-throttle keep track of the same stats multiple times. Unify them" * 'for-4.3/blkcg' of git://git.kernel.dk/linux-block: (45 commits) blkcg: use CGROUP_WEIGHT_* scale for io.weight on the unified hierarchy blkcg: s/CFQ_WEIGHT_*/CFQ_WEIGHT_LEGACY_*/ blkcg: implement interface for the unified hierarchy blkcg: misc preparations for unified hierarchy interface blkcg: separate out tg_conf_updated() from tg_set_conf() blkcg: move body parsing from blkg_conf_prep() to its callers blkcg: mark existing cftypes as legacy blkcg: rename subsystem name from blkio to io blkcg: refine error codes returned during blkcg configuration blkcg: remove unnecessary NULL checks from __cfqg_set_weight_device() blkcg: reduce stack usage of blkg_rwstat_recursive_sum() blkcg: remove cfqg_stats->sectors blkcg: move io_service_bytes and io_serviced stats into blkcg_gq blkcg: make blkg_[rw]stat_recursive_sum() to be able to index into blkcg_gq blkcg: make blkcg_[rw]stat per-cpu blkcg: add blkg_[rw]stat->aux_cnt and replace cfq_group->dead_stats with it blkcg: consolidate blkg creation in blkcg_bio_issue_check() blk-throttle: improve queue bypass handling blkcg: move root blkg lookup optimization from throtl_lookup_tg() to __blkg_lookup() blkcg: inline [__]blkg_lookup() ...
| * writeback: update writeback tracepoints to report cgroupTejun Heo2015-08-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The following tracepoints are updated to report the cgroup used during cgroup writeback. * writeback_write_inode[_start] * writeback_queue * writeback_exec * writeback_start * writeback_written * writeback_wait * writeback_nowork * writeback_wake_background * wbc_writepage * writeback_queue_io * bdi_dirty_ratelimit * balance_dirty_pages * writeback_sb_inodes_requeue * writeback_single_inode[_start] Note that writeback_bdi_register is separated out from writeback_class as reporting cgroup doesn't make sense to it. Tracepoints which take bdi are updated to take bdi_writeback instead. Signed-off-by: Tejun Heo <tj@kernel.org> Suggested-by: Jan Kara <jack@suse.cz> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Jens Axboe <axboe@fb.com>
| * writeback: explain why @inode is allowed to be NULL for inode_congested()Tejun Heo2015-08-18
| | | | | | | | | | | | Signed-off-by: Tejun Heo <tj@kernel.org> Suggested-by: Jan Kara <jack@suse.cz> Signed-off-by: Jens Axboe <axboe@fb.com>
| * writeback: remove wb_writeback_work->single_wait/doneTejun Heo2015-08-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | wb_writeback_work->single_wait/done are used for the wait mechanism for synchronous wb_work (wb_writeback_work) items which are issued when bdi_split_work_to_wbs() fails to allocate memory for asynchronous wb_work items; however, there's no reason to use a separate wait mechanism for this. bdi_split_work_to_wbs() can simply use on-stack fallback wb_work item and separate wb_completion to wait for it. This patch removes wb_work->single_wait/done and the related code and make bdi_split_work_to_wbs() use on-stack fallback wb_work and wb_completion instead. Signed-off-by: Tejun Heo <tj@kernel.org> Suggested-by: Jan Kara <jack@suse.cz> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Jens Axboe <axboe@fb.com>
| * writeback: bdi_for_each_wb() iteration is memcg ID based not blkcgTejun Heo2015-08-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | wb's (bdi_writeback's) are currently keyed by memcg ID; however, in an earlier implementation, wb's were keyed by blkcg ID. bdi_for_each_wb() walks bdi->cgwb_tree in the ascending ID order and allows iterations to start from an arbitrary ID which is used to interrupt and resume iterations. Unfortunately, while changing wb to be keyed by memcg ID instead of blkcg, bdi_for_each_wb() was missed and is still assuming that wb's are keyed by blkcg ID. This doesn't affect iterations which don't get interrupted but bdi_split_work_to_wbs() makes use of iteration resuming on allocation failures and thus may incorrectly skip or repeat wb's. Fix it by changing bdi_for_each_wb() to take memcg IDs instead of blkcg IDs and updating bdi_split_work_to_wbs() accordingly. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <axboe@fb.com>
* | Merge branch 'for-linus' of ↵Linus Torvalds2015-09-05
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs updates from Al Viro: "In this one: - d_move fixes (Eric Biederman) - UFS fixes (me; locking is mostly sane now, a bunch of bugs in error handling ought to be fixed) - switch of sb_writers to percpu rwsem (Oleg Nesterov) - superblock scalability (Josef Bacik and Dave Chinner) - swapon(2) race fix (Hugh Dickins)" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (65 commits) vfs: Test for and handle paths that are unreachable from their mnt_root dcache: Reduce the scope of i_lock in d_splice_alias dcache: Handle escaped paths in prepend_path mm: fix potential data race in SyS_swapon inode: don't softlockup when evicting inodes inode: rename i_wb_list to i_io_list sync: serialise per-superblock sync operations inode: convert inode_sb_list_lock to per-sb inode: add hlist_fake to avoid the inode hash lock in evict writeback: plug writeback at a high level change sb_writers to use percpu_rw_semaphore shift percpu_counter_destroy() into destroy_super_work() percpu-rwsem: kill CONFIG_PERCPU_RWSEM percpu-rwsem: introduce percpu_rwsem_release() and percpu_rwsem_acquire() percpu-rwsem: introduce percpu_down_read_trylock() document rwsem_release() in sb_wait_write() fix the broken lockdep logic in __sb_start_write() introduce __sb_writers_{acquired,release}() helpers ufs_inode_get{frag,block}(): get rid of 'phys' argument ufs_getfrag_block(): tidy up a bit ...
| * | inode: rename i_wb_list to i_io_listDave Chinner2015-08-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There's a small consistency problem between the inode and writeback naming. Writeback calls the "for IO" inode queues b_io and b_more_io, but the inode calls these the "writeback list" or i_wb_list. This makes it hard to an new "under writeback" list to the inode, or call it an "under IO" list on the bdi because either way we'll have writeback on IO and IO on writeback and it'll just be confusing. I'm getting confused just writing this! So, rename the inode "for IO" list variable to i_io_list so we can add a new "writeback list" in a subsequent patch. Signed-off-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Josef Bacik <jbacik@fb.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Christoph Hellwig <hch@lst.de> Tested-by: Dave Chinner <dchinner@redhat.com>
| * | sync: serialise per-superblock sync operationsDave Chinner2015-08-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When competing sync(2) calls walk the same filesystem, they need to walk the list of inodes on the superblock to find all the inodes that we need to wait for IO completion on. However, when multiple wait_sb_inodes() calls do this at the same time, they contend on the the inode_sb_list_lock and the contention causes system wide slowdowns. In effect, concurrent sync(2) calls can take longer and burn more CPU than if they were serialised. Stop the worst of the contention by adding a per-sb mutex to wrap around wait_sb_inodes() so that we only execute one sync(2) IO completion walk per superblock superblock at a time and hence avoid contention being triggered by concurrent sync(2) calls. Signed-off-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Josef Bacik <jbacik@fb.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Christoph Hellwig <hch@lst.de> Tested-by: Dave Chinner <dchinner@redhat.com>
| * | inode: convert inode_sb_list_lock to per-sbDave Chinner2015-08-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The process of reducing contention on per-superblock inode lists starts with moving the locking to match the per-superblock inode list. This takes the global lock out of the picture and reduces the contention problems to within a single filesystem. This doesn't get rid of contention as the locks still have global CPU scope, but it does isolate operations on different superblocks form each other. Signed-off-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Josef Bacik <jbacik@fb.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Christoph Hellwig <hch@lst.de> Tested-by: Dave Chinner <dchinner@redhat.com>
| * | writeback: plug writeback at a high levelDave Chinner2015-08-17
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Doing writeback on lots of little files causes terrible IOPS storms because of the per-mapping writeback plugging we do. This essentially causes imeediate dispatch of IO for each mapping, regardless of the context in which writeback is occurring. IOWs, running a concurrent write-lots-of-small 4k files using fsmark on XFS results in a huge number of IOPS being issued for data writes. Metadata writes are sorted and plugged at a high level by XFS, so aggregate nicely into large IOs. However, data writeback IOs are dispatched in individual 4k IOs, even when the blocks of two consecutively written files are adjacent. Test VM: 8p, 8GB RAM, 4xSSD in RAID0, 100TB sparse XFS filesystem, metadata CRCs enabled. Kernel: 3.10-rc5 + xfsdev + my 3.11 xfs queue (~70 patches) Test: $ ./fs_mark -D 10000 -S0 -n 10000 -s 4096 -L 120 -d /mnt/scratch/0 -d /mnt/scratch/1 -d /mnt/scratch/2 -d /mnt/scratch/3 -d /mnt/scratch/4 -d /mnt/scratch/5 -d /mnt/scratch/6 -d /mnt/scratch/7 Result: wall sys create rate Physical write IO time CPU (avg files/s) IOPS Bandwidth ----- ----- ------------ ------ --------- unpatched 6m56s 15m47s 24,000+/-500 26,000 130MB/s patched 5m06s 13m28s 32,800+/-600 1,500 180MB/s improvement -26.44% -14.68% +36.67% -94.23% +38.46% If I use zero length files, this workload at about 500 IOPS, so plugging drops the data IOs from roughly 25,500/s to 1000/s. 3 lines of code, 35% better throughput for 15% less CPU. The benefits of plugging at this layer are likely to be higher for spinning media as the IO patterns for this workload are going make a much bigger difference on high IO latency devices..... Signed-off-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Josef Bacik <jbacik@fb.com> Reviewed-by: Jan Kara <jack@suse.cz> Tested-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
* / writeback: sync_inodes_sb() must write out I_DIRTY_TIME inodes and always ↵Tejun Heo2015-08-25
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | call wait_sb_inodes() e79729123f63 ("writeback: don't issue wb_writeback_work if clean") updated writeback path to avoid kicking writeback work items if there are no inodes to be written out; unfortunately, the avoidance logic was too aggressive and broke sync_inodes_sb(). * sync_inodes_sb() must write out I_DIRTY_TIME inodes but I_DIRTY_TIME inodes dont't contribute to bdi/wb_has_dirty_io() tests and were being skipped over. * inodes are taken off wb->b_dirty/io/more_io lists after writeback starts on them. sync_inodes_sb() skipping wait_sb_inodes() when bdi_has_dirty_io() breaks it by making it return while writebacks are in-flight. This patch fixes the breakages by * Removing bdi_has_dirty_io() shortcut from bdi_split_work_to_wbs(). The callers are already testing the condition. * Removing bdi_has_dirty_io() shortcut from sync_inodes_sb() so that it always calls into bdi_split_work_to_wbs() and wait_sb_inodes(). * Making bdi_split_work_to_wbs() consider the b_dirty_time list for WB_SYNC_ALL writebacks. Kudos to Eryu, Dave and Jan for tracking down the issue. Signed-off-by: Tejun Heo <tj@kernel.org> Fixes: e79729123f63 ("writeback: don't issue wb_writeback_work if clean") Link: http://lkml.kernel.org/g/20150812101204.GE17933@dhcp-13-216.nay.redhat.com Reported-and-bisected-by: Eryu Guan <eguan@redhat.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Jan Kara <jack@suse.com> Cc: Ted Ts'o <tytso@google.com> Signed-off-by: Jens Axboe <axboe@fb.com>
* block: export bio_associate_*() and wbc_account_io()Tejun Heo2015-07-23
| | | | | | | | | | bio_associate_blkcg(), bio_associate_current() and wbc_account_io() are used to implement cgroup writeback support for filesystems and thus need to be exported. Export them. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Jens Axboe <axboe@fb.com>
* writeback: do foreign inode detection iff cgroup writeback is enabledTejun Heo2015-06-17
| | | | | | | | | | | | | | | | Currently, even when a filesystem doesn't set the FS_CGROUP_WRITEBACK flag, if the filesystem uses wbc_init_bio() and wbc_account_io(), the foreign inode detection and migration logic still ends up activating cgroup writeback which is unexpected. This patch ensures that the foreign inode detection logic stays disabled when inode_cgwb_enabled() is false by not associating writeback_control's with bdi_writeback's. This also avoids unnecessary operations in wbc_init_bio(), wbc_account_io() and wbc_detach_inode() for filesystems which don't support cgroup writeback. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <axboe@fb.com>
* writeback: disassociate inodes from dying bdi_writebacksTejun Heo2015-06-02
| | | | | | | | | | | | | | | | | | | | | | | | | | | | For the purpose of foreign inode detection, wb's (bdi_writeback's) are identified by the associated memcg ID. As we create a separate wb for each memcg, this is enough to identify the active wb's; however, when blkcg is enabled or disabled higher up in the hierarchy, the mapping between memcg and blkcg changes which in turn creates a new wb to service the new mapping. The old wb is unlinked from index and released after all references are drained. The foreign inode detection logic can't detect this condition because both the old and new wb's point to the same memcg and thus never decides to move inodes attached to the old wb to the new one. This patch adds logic to initiate switching immediately in wbc_attach_and_unlock_inode() if the associated wb is dying. We can make the usual foreign detection logic to distinguish the different wb's mapped to the memcg but the dying wb is never gonna be in active service again and there's no point in tracking the usage history and reaching the switch verdict after enough data points are collected. It's already known that the wb has to be switched. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: Jan Kara <jack@suse.cz> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Greg Thelen <gthelen@google.com> Signed-off-by: Jens Axboe <axboe@fb.com>
* writeback: implement foreign cgroup inode bdi_writeback switchingTejun Heo2015-06-02
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As concurrent write sharing of an inode is expected to be very rare and memcg only tracks page ownership on first-use basis severely confining the usefulness of such sharing, cgroup writeback tracks ownership per-inode. While the support for concurrent write sharing of an inode is deemed unnecessary, an inode being written to by different cgroups at different points in time is a lot more common, and, more importantly, charging only by first-use can too readily lead to grossly incorrect behaviors (single foreign page can lead to gigabytes of writeback to be incorrectly attributed). To resolve this issue, cgroup writeback detects the majority dirtier of an inode and transfers the ownership to it. The previous patches implemented the foreign condition detection mechanism and laid the groundwork. This patch implements the actual switching. With the previously implemented [unlocked_]inode_to_wb_and_list_lock() and wb stat transaction, grabbing wb->list_lock, inode->i_lock and mapping->tree_lock gives us full exclusion against all wb operations on the target inode. inode_switch_wb_work_fn() grabs all the locks and transfers the inode atomically along with its RECLAIMABLE and WRITEBACK stats. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: Jan Kara <jack@suse.cz> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Greg Thelen <gthelen@google.com> Signed-off-by: Jens Axboe <axboe@fb.com>
* writeback: add lockdep annotation to inode_to_wb()Tejun Heo2015-06-02
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With the previous three patches, all operations which acquire wb from inode are either under one of inode->i_lock, mapping->tree_lock or wb->list_lock or protected by unlocked_inode_to_wb transaction. This will be depended upon by foreign inode wb switching. This patch adds lockdep assertion to inode_to_wb() so that usages outside the above list locks can be caught easily. There are three exceptions. * locked_inode_to_wb_and_lock_list() is holding wb->list_lock but the wb may not be the inode's. Ensuring that is the function's role after all. Updated to deref inode->i_wb directly. * inode_wb_stat_unlocked_begin() is usually protected by combination of !I_WB_SWITCH and rcu_read_lock(). Updated to deref inode->i_wb directly. * inode_congested() wants to test whether inode->i_wb is set before starting the transaction. Added inode_to_wb_is_valid() which tests inode->i_wb directly. v5: might_lock() removed. It annotates that the lock is grabbed w/ irq enabled which isn't the case and triggering lockdep warning spuriously. v4: might_lock() added to unlocked_inode_to_wb_begin(). v3: inode_congested() conversion added. v2: locked_inode_to_wb_and_lock_list() was missing in the first version. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: Jan Kara <jack@suse.cz> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Greg Thelen <gthelen@google.com> Signed-off-by: Jens Axboe <axboe@fb.com>
* writeback: use unlocked_inode_to_wb transaction in inode_congested()Tejun Heo2015-06-02
| | | | | | | | | | | | | | | | | | | Similar to wb stat updates, inode_congested() accesses the associated wb of an inode locklessly, which will break with foreign inode wb switching. This path updates inode_congested() to use unlocked inode wb access transaction introduced by the previous patch. Combined with the previous two patches, this makes all wb list and access operations to be protected by either of inode->i_lock, wb->list_lock, or mapping->tree_lock while wb switching is in progress. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: Jan Kara <jack@suse.cz> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Greg Thelen <gthelen@google.com> Signed-off-by: Jens Axboe <axboe@fb.com>
* writeback: implement unlocked_inode_to_wb transaction and use it for stat ↵Tejun Heo2015-06-02
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | updates The mechanism for detecting whether an inode should switch its wb (bdi_writeback) association is now in place. This patch build the framework for the actual switching. This patch adds a new inode flag I_WB_SWITCHING, which has two functions. First, the easy one, it ensures that there's only one switching in progress for a give inode. Second, it's used as a mechanism to synchronize wb stat updates. The two stats, WB_RECLAIMABLE and WB_WRITEBACK, aren't event counters but track the current number of dirty pages and pages under writeback respectively. As such, when an inode is moved from one wb to another, the inode's portion of those stats have to be transferred together; unfortunately, this is a bit tricky as those stat updates are percpu operations which are performed without holding any lock in some places. This patch solves the problem in a similar way as memcg. Each such lockless stat updates are wrapped in transaction surrounded by unlocked_inode_to_wb_begin/end(). During normal operation, they map to rcu_read_lock/unlock(); however, if I_WB_SWITCHING is asserted, mapping->tree_lock is grabbed across the transaction. In turn, the switching path sets I_WB_SWITCHING and waits for a RCU grace period to pass before actually starting to switch, which guarantees that all stat update paths are synchronizing against mapping->tree_lock. This patch still doesn't implement the actual switching. v3: Updated on top of the recent cancel_dirty_page() updates. unlocked_inode_to_wb_begin() now nests inside mem_cgroup_begin_page_stat() to match the locking order. v2: The i_wb access transaction will be used for !stat accesses too. Function names and comments updated accordingly. s/inode_wb_stat_unlocked_{begin|end}/unlocked_inode_to_wb_{begin|end}/ s/switch_wb/switch_wbs/ Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: Jan Kara <jack@suse.cz> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Greg Thelen <gthelen@google.com> Signed-off-by: Jens Axboe <axboe@fb.com>
* writeback: implement [locked_]inode_to_wb_and_lock_list()Tejun Heo2015-06-02
| | | | | | | | | | | | | | | | | | | | | | | | | cgroup writeback currently assumes that inode to wb association doesn't change; however, with the planned foreign inode wb switching mechanism, the association will change dynamically. When an inode needs to be put on one of the IO lists of its wb, the current code simply calls inode_to_wb() and locks the returned wb; however, with the planned wb switching, the association may change before locking the wb and may even get released. This patch implements [locked_]inode_to_wb_and_lock_list() which pins the associated wb while holding i_lock, releases it, acquires wb->list_lock and verifies that the association hasn't changed inbetween. As the association will be protected by both locks among other things, this guarantees that the wb is the inode's associated wb until the list_lock is released. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: Jan Kara <jack@suse.cz> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Greg Thelen <gthelen@google.com> Signed-off-by: Jens Axboe <axboe@fb.com>
* writeback: implement foreign cgroup inode detectionTejun Heo2015-06-02
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As concurrent write sharing of an inode is expected to be very rare and memcg only tracks page ownership on first-use basis severely confining the usefulness of such sharing, cgroup writeback tracks ownership per-inode. While the support for concurrent write sharing of an inode is deemed unnecessary, an inode being written to by different cgroups at different points in time is a lot more common, and, more importantly, charging only by first-use can too readily lead to grossly incorrect behaviors (single foreign page can lead to gigabytes of writeback to be incorrectly attributed). To resolve this issue, cgroup writeback detects the majority dirtier of an inode and will transfer the ownership to it. To avoid unnnecessary oscillation, the detection mechanism keeps track of history and gives out the switch verdict only if the foreign usage pattern is stable over a certain amount of time and/or writeback attempts. The detection mechanism has fairly low space and computation overhead. It adds 8 bytes to struct inode (one int and two u16's) and minimal amount of calculation per IO. The detection mechanism converges to the correct answer usually in several seconds of IO time when there's a clear majority dirtier. Even when there isn't, it can reach an acceptable answer fairly quickly under most circumstances. Please see wb_detach_inode() for more details. This patch only implements detection. Following patches will implement actual switching. v2: wbc_account_io() now checks whether the wbc is associated with a wb before dereferencing it. This can happen when pageout() is writing pages directly without going through the usual writeback path. As pageout() path is single-threaded, we don't want it to be blocked behind a slow cgroup and ultimately want it to delegate actual writing to the usual writeback path. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: Jan Kara <jack@suse.cz> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Greg Thelen <gthelen@google.com> Signed-off-by: Jens Axboe <axboe@fb.com>
* writeback: make writeback_control track the inode being written backTejun Heo2015-06-02
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, for cgroup writeback, the IO submission paths directly associate the bio's with the blkcg from inode_to_wb_blkcg_css(); however, it'd be necessary to keep more writeback context to implement foreign inode writeback detection. wbc (writeback_control) is the natural fit for the extra context - it persists throughout the writeback of each inode and is passed all the way down to IO submission paths. This patch adds wbc_attach_and_unlock_inode(), wbc_detach_inode(), and wbc_attach_fdatawrite_inode() which are used to associate wbc with the inode being written back. IO submission paths now use wbc_init_bio() instead of directly associating bio's with blkcg themselves. This leaves inode_to_wb_blkcg_css() w/o any user. The function is removed. wbc currently only tracks the associated wb (bdi_writeback). Future patches will add more for foreign inode detection. The association is established under i_lock which will be depended upon when migrating foreign inodes to other wb's. As currently, once established, inode to wb association never changes, going through wbc when initializing bio's doesn't cause any behavior changes. v2: submit_blk_blkcg() now checks whether the wbc is associated with a wb before dereferencing it. This can happen when pageout() is writing pages directly without going through the usual writeback path. As pageout() path is single-threaded, we don't want it to be blocked behind a slow cgroup and ultimately want it to delegate actual writing to the usual writeback path. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: Jan Kara <jack@suse.cz> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Greg Thelen <gthelen@google.com> Signed-off-by: Jens Axboe <axboe@fb.com>
* writeback: relocate wb[_try]_get(), wb_put(), inode_{attach|detach}_wb()Tejun Heo2015-06-02
| | | | | | | | | | | | | | | | | | | | | | | Currently, majority of cgroup writeback support including all the above functions are implemented in include/linux/backing-dev.h and mm/backing-dev.c; however, the portion closely related to writeback logic implemented in include/linux/writeback.h and mm/page-writeback.c will expand to support foreign writeback detection and correction. This patch moves wb[_try]_get() and wb_put() to include/linux/backing-dev-defs.h so that they can be used from writeback.h and inode_{attach|detach}_wb() to writeback.h and page-writeback.c. This is pure reorganization and doesn't introduce any functional changes. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: Jan Kara <jack@suse.cz> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Greg Thelen <gthelen@google.com> Signed-off-by: Jens Axboe <axboe@fb.com>
* writeback: move over_bground_thresh() to mm/page-writeback.cTejun Heo2015-06-02
| | | | | | | | | | | | | | | | | | | and rename it to wb_over_bg_thresh(). The function is closely tied to the dirty throttling mechanism implemented in page-writeback.c. This relocation will allow future updates necessary for cgroup writeback support. While at it, add function comment. This is pure reorganization and doesn't introduce any behavioral changes. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: Jan Kara <jack@suse.cz> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Greg Thelen <gthelen@google.com> Signed-off-by: Jens Axboe <axboe@fb.com>
* writeback: move global_dirty_limit into wb_domainTejun Heo2015-06-02
| | | | | | | | | | | | | | | | | | | | | This patch is a part of the series to define wb_domain which represents a domain that wb's (bdi_writeback's) belong to and are measured against each other in. This will enable IO backpressure propagation for cgroup writeback. global_dirty_limit exists to regulate the global dirty threshold which is a property of the wb_domain. This patch moves hard_dirty_limit, dirty_lock, and update_time into wb_domain. This is pure reorganization and doesn't introduce any behavioral changes. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: Jan Kara <jack@suse.cz> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Greg Thelen <gthelen@google.com> Signed-off-by: Jens Axboe <axboe@fb.com>
* writeback: reorganize [__]wb_update_bandwidth()Tejun Heo2015-06-02
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | __wb_update_bandwidth() is called from two places - fs/fs-writeback.c::balance_dirty_pages() and mm/page-writeback.c::wb_writeback(). The latter updates only the write bandwidth while the former also deals with the dirty ratelimit. The two callsites are distinguished by whether @thresh parameter is zero or not, which is cryptic. In addition, the two files define their own different versions of wb_update_bandwidth() on top of __wb_update_bandwidth(), which is confusing to say the least. This patch cleans up [__]wb_update_bandwidth() in the following ways. * __wb_update_bandwidth() now takes explicit @update_ratelimit parameter to gate dirty ratelimit handling. * mm/page-writeback.c::wb_update_bandwidth() is flattened into its caller - balance_dirty_pages(). * fs/fs-writeback.c::wb_update_bandwidth() is moved to mm/page-writeback.c and __wb_update_bandwidth() is made static. * While at it, add a lockdep assertion to __wb_update_bandwidth(). Except for the lockdep addition, this is pure reorganization and doesn't introduce any behavioral changes. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: Jan Kara <jack@suse.cz> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Greg Thelen <gthelen@google.com> Signed-off-by: Jens Axboe <axboe@fb.com>