[v2,0/8] cleanup llseek and splice

The goal of this patchset is to enable splicing to internal pipes for select chardevs where it makes sense to do so. In the process, however, it was revealed that many regular files are problematic here. The key insight is that splicing to internal pipes is okay so long as the splice operation is rewindable. That means these devices need to be llseekable. So the series first tries to make llseek a bit tamer, fixing up the long-standing tension between llseek==NULL vs llseek==no_llseek vs ~FMODE_LSEEK. With FMODE_LSEEK as good information, the series is able to adjust internal pipe splicing to use that. It is then able to remove no_llseek entirely, and make all checks use FMODE_LSEEK and all invocations use vfs_llseek. Along the way the series also fixes related bugs in ksmbd, dma-buf, and vfio. Jason A. Donenfeld (8): ksmbd: use vfs_llseek instead of dereferencing NULL fs: do not set no_llseek in fops fs: clear or set FMODE_LSEEK based on llseek function fs: check FMODE_LSEEK to control internal pipe splicing fs: do not compare against ->llseek fs: remove no_llseek dma-buf: remove useless FMODE_LSEEK flag vfio: do not set FMODE_LSEEK flag .../watchdog/convert_drivers_to_kernel_api.rst | 1 - arch/parisc/kernel/perf.c | 1 - arch/powerpc/kernel/eeh.c | 4 ---- arch/powerpc/platforms/52xx/mpc52xx_gpt.c | 1 - arch/powerpc/platforms/cell/spufs/file.c | 17 ----------------- arch/powerpc/platforms/powernv/eeh-powernv.c | 1 - arch/powerpc/platforms/pseries/dtl.c | 1 - arch/s390/hypfs/hypfs_dbfs.c | 1 - arch/s390/hypfs/inode.c | 1 - arch/s390/kernel/debug.c | 1 - arch/s390/kernel/perf_cpum_cf.c | 1 - arch/s390/kernel/sysinfo.c | 1 - arch/s390/pci/pci_clp.c | 1 - arch/um/drivers/harddog_kern.c | 1 - arch/um/drivers/hostaudio_kern.c | 2 -- arch/x86/kernel/cpu/mce/dev-mcelog.c | 1 - arch/x86/kernel/cpu/resctrl/pseudo_lock.c | 1 - drivers/acpi/apei/erst-dbg.c | 1 - drivers/auxdisplay/charlcd.c | 1 - drivers/block/mtip32xx/mtip32xx.c | 3 --- drivers/block/pktcdvd.c | 1 - drivers/bluetooth/hci_vhci.c | 1 - drivers/bus/moxtet.c | 2 -- drivers/char/agp/frontend.c | 1 - drivers/char/applicom.c | 1 - drivers/char/ds1620.c | 1 - drivers/char/dtlk.c | 1 - drivers/char/hpet.c | 1 - drivers/char/ipmi/ipmi_watchdog.c | 1 - drivers/char/pc8736x_gpio.c | 1 - drivers/char/pcmcia/cm4000_cs.c | 1 - drivers/char/pcmcia/cm4040_cs.c | 1 - drivers/char/pcmcia/scr24x_cs.c | 1 - drivers/char/ppdev.c | 1 - drivers/char/scx200_gpio.c | 1 - drivers/char/sonypi.c | 1 - drivers/char/tb0219.c | 1 - drivers/char/tpm/tpm-dev.c | 1 - drivers/char/tpm/tpm_vtpm_proxy.c | 1 - drivers/char/tpm/tpmrm-dev.c | 1 - drivers/char/virtio_console.c | 1 - drivers/counter/counter-chrdev.c | 1 - drivers/dma-buf/dma-buf.c | 1 - drivers/firewire/core-cdev.c | 1 - drivers/firmware/efi/capsule-loader.c | 1 - drivers/firmware/efi/test/efi_test.c | 1 - drivers/firmware/turris-mox-rwtm.c | 1 - drivers/gnss/core.c | 1 - drivers/gpio/gpio-mockup.c | 1 - drivers/gpio/gpiolib-cdev.c | 1 - drivers/gpu/drm/drm_file.c | 4 +--- drivers/gpu/drm/i915/i915_perf.c | 1 - drivers/gpu/drm/msm/msm_perf.c | 1 - drivers/gpu/drm/msm/msm_rd.c | 1 - drivers/hid/uhid.c | 1 - drivers/hwmon/asus_atk0110.c | 1 - drivers/hwmon/fschmd.c | 1 - drivers/hwmon/w83793.c | 1 - drivers/hwtracing/coresight/coresight-etb10.c | 1 - .../hwtracing/coresight/coresight-tmc-core.c | 1 - drivers/hwtracing/intel_th/msu.c | 1 - drivers/hwtracing/stm/core.c | 1 - drivers/i2c/i2c-dev.c | 1 - drivers/infiniband/core/ucma.c | 1 - drivers/infiniband/core/user_mad.c | 2 -- drivers/infiniband/core/uverbs_main.c | 4 ---- drivers/infiniband/hw/hfi1/fault.c | 1 - drivers/infiniband/hw/mlx5/devx.c | 2 -- drivers/input/evdev.c | 1 - drivers/input/joydev.c | 1 - drivers/input/keyboard/applespi.c | 1 - drivers/input/misc/uinput.c | 1 - drivers/input/serio/userio.c | 1 - drivers/isdn/capi/capi.c | 1 - drivers/isdn/mISDN/timerdev.c | 1 - drivers/leds/uleds.c | 1 - drivers/macintosh/adb.c | 1 - drivers/macintosh/smu.c | 1 - drivers/media/cec/core/cec-api.c | 1 - drivers/media/mc/mc-devnode.c | 1 - drivers/media/rc/lirc_dev.c | 1 - drivers/media/usb/uvc/uvc_debugfs.c | 1 - drivers/media/v4l2-core/v4l2-dev.c | 1 - drivers/message/fusion/mptctl.c | 1 - drivers/misc/lis3lv02d/lis3lv02d.c | 1 - drivers/misc/mei/main.c | 1 - drivers/misc/phantom.c | 1 - drivers/mmc/core/block.c | 1 - drivers/mtd/ubi/cdev.c | 2 -- drivers/mtd/ubi/debug.c | 1 - drivers/net/netdevsim/fib.c | 1 - drivers/net/tap.c | 1 - drivers/net/tun.c | 1 - .../wireless/broadcom/brcm80211/brcmfmac/core.c | 1 - drivers/net/wireless/intel/iwlwifi/mvm/d3.c | 1 - drivers/pinctrl/pinmux.c | 1 - drivers/platform/chrome/cros_ec_debugfs.c | 1 - drivers/platform/chrome/wilco_ec/debugfs.c | 1 - drivers/platform/chrome/wilco_ec/event.c | 1 - drivers/platform/chrome/wilco_ec/telemetry.c | 1 - .../platform/surface/surface_aggregator_cdev.c | 1 - drivers/platform/surface/surface_dtx.c | 1 - drivers/pps/pps.c | 1 - drivers/rtc/dev.c | 1 - drivers/rtc/rtc-m41t80.c | 1 - drivers/s390/char/fs3270.c | 1 - drivers/s390/char/sclp_ctl.c | 1 - drivers/s390/char/tape_char.c | 1 - drivers/s390/char/uvdevice.c | 1 - drivers/s390/char/vmcp.c | 1 - drivers/s390/char/vmlogrdr.c | 1 - drivers/s390/char/zcore.c | 2 -- drivers/s390/cio/chsc_sch.c | 1 - drivers/s390/cio/css.c | 1 - drivers/s390/crypto/pkey_api.c | 1 - drivers/s390/crypto/zcrypt_api.c | 1 - drivers/sbus/char/openprom.c | 1 - drivers/sbus/char/uctrl.c | 1 - drivers/scsi/sg.c | 1 - drivers/spi/spidev.c | 1 - drivers/staging/pi433/pi433_if.c | 1 - .../intel/int340x_thermal/acpi_thermal_rel.c | 1 - drivers/tty/tty_io.c | 3 --- drivers/usb/gadget/function/f_fs.c | 2 -- drivers/usb/gadget/legacy/inode.c | 2 -- drivers/usb/gadget/legacy/raw_gadget.c | 1 - drivers/usb/gadget/udc/atmel_usba_udc.c | 1 - drivers/usb/misc/ftdi-elan.c | 1 - drivers/usb/misc/ldusb.c | 1 - drivers/usb/mon/mon_bin.c | 1 - drivers/usb/mon/mon_stat.c | 1 - drivers/usb/mon/mon_text.c | 2 -- drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c | 2 -- drivers/vfio/pci/mlx5/main.c | 2 -- drivers/vfio/vfio.c | 2 +- drivers/watchdog/acquirewdt.c | 1 - drivers/watchdog/advantechwdt.c | 1 - drivers/watchdog/alim1535_wdt.c | 1 - drivers/watchdog/alim7101_wdt.c | 1 - drivers/watchdog/ar7_wdt.c | 1 - drivers/watchdog/at91rm9200_wdt.c | 1 - drivers/watchdog/ath79_wdt.c | 1 - drivers/watchdog/cpu5wdt.c | 1 - drivers/watchdog/cpwd.c | 1 - drivers/watchdog/eurotechwdt.c | 1 - drivers/watchdog/gef_wdt.c | 1 - drivers/watchdog/geodewdt.c | 1 - drivers/watchdog/ib700wdt.c | 1 - drivers/watchdog/ibmasr.c | 1 - drivers/watchdog/indydog.c | 1 - drivers/watchdog/it8712f_wdt.c | 1 - drivers/watchdog/m54xx_wdt.c | 1 - drivers/watchdog/machzwd.c | 1 - drivers/watchdog/mixcomwd.c | 1 - drivers/watchdog/mtx-1_wdt.c | 1 - drivers/watchdog/nv_tco.c | 1 - drivers/watchdog/pc87413_wdt.c | 1 - drivers/watchdog/pcwd.c | 2 -- drivers/watchdog/pcwd_pci.c | 2 -- drivers/watchdog/pcwd_usb.c | 2 -- drivers/watchdog/pika_wdt.c | 1 - drivers/watchdog/rc32434_wdt.c | 1 - drivers/watchdog/rdc321x_wdt.c | 1 - drivers/watchdog/riowd.c | 1 - drivers/watchdog/sa1100_wdt.c | 1 - drivers/watchdog/sb_wdog.c | 1 - drivers/watchdog/sbc60xxwdt.c | 1 - drivers/watchdog/sbc7240_wdt.c | 1 - drivers/watchdog/sbc8360.c | 1 - drivers/watchdog/sbc_epx_c3.c | 1 - drivers/watchdog/sbc_fitpc2_wdt.c | 1 - drivers/watchdog/sc1200wdt.c | 1 - drivers/watchdog/sc520_wdt.c | 1 - drivers/watchdog/sch311x_wdt.c | 1 - drivers/watchdog/scx200_wdt.c | 1 - drivers/watchdog/smsc37b787_wdt.c | 1 - drivers/watchdog/w83877f_wdt.c | 1 - drivers/watchdog/w83977f_wdt.c | 1 - drivers/watchdog/wafer5823wdt.c | 1 - drivers/watchdog/wdrtas.c | 2 -- drivers/watchdog/wdt.c | 2 -- drivers/watchdog/wdt285.c | 1 - drivers/watchdog/wdt977.c | 1 - drivers/watchdog/wdt_pci.c | 2 -- drivers/xen/evtchn.c | 1 - drivers/xen/mcelog.c | 1 - drivers/xen/xenbus/xenbus_dev_frontend.c | 1 - fs/coredump.c | 4 ++-- fs/debugfs/file.c | 1 - fs/dlm/debug_fs.c | 1 - fs/efivarfs/file.c | 1 - fs/file_table.c | 2 ++ fs/fsopen.c | 1 - fs/fuse/control.c | 4 ---- fs/fuse/dev.c | 1 - fs/ksmbd/vfs.c | 4 ++-- fs/nsfs.c | 1 - fs/open.c | 2 ++ fs/overlayfs/copy_up.c | 3 +-- fs/pipe.c | 1 - fs/read_write.c | 16 +++------------- fs/splice.c | 10 ++++------ fs/ubifs/debug.c | 2 -- include/linux/debugfs.h | 1 - include/linux/fs.h | 1 - kernel/bpf/bpf_iter.c | 1 - kernel/events/core.c | 1 - kernel/power/user.c | 1 - kernel/relay.c | 1 - kernel/time/posix-clock.c | 1 - kernel/trace/trace.c | 3 --- mm/huge_memory.c | 1 - net/mac80211/rc80211_minstrel_ht_debugfs.c | 2 -- net/rfkill/core.c | 1 - net/socket.c | 1 - net/sunrpc/cache.c | 4 ---- net/sunrpc/rpc_pipe.c | 1 - scripts/coccinelle/api/stream_open.cocci | 1 - sound/core/control.c | 1 - sound/core/oss/mixer_oss.c | 1 - sound/core/oss/pcm_oss.c | 1 - sound/core/pcm_native.c | 2 -- sound/core/rawmidi.c | 1 - sound/core/seq/seq_clientmgr.c | 1 - sound/core/timer.c | 1 - sound/oss/dmasound/dmasound_core.c | 3 --- virt/kvm/kvm_main.c | 1 - 227 files changed, 18 insertions(+), 303 deletions(-)

Message ID	20220625110115.39956-1-Jason@zx2c4.com (mailing list archive)
Headers	show Return-Path: <linux-fsdevel-owner@kernel.org> From: "Jason A. Donenfeld" <Jason@zx2c4.com> To: linux-kernel@vger.kernel.org, viro@zeniv.linux.org.uk, Jens Axboe <axboe@kernel.dk>, linux-fsdevel@vger.kernel.org Cc: "Jason A. Donenfeld" <Jason@zx2c4.com> Subject: [PATCH v2 0/8] cleanup llseek and splice Date: Sat, 25 Jun 2022 13:01:07 +0200 Message-Id: <20220625110115.39956-1-Jason@zx2c4.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk
Series	cleanup llseek and splice \| expand [v2,0/8] cleanup llseek and splice [v2,1/8] ksmbd: use vfs_llseek instead of dereferencing NULL [v2,2/8] fs: do not set no_llseek in fops [v2,3/8] fs: clear or set FMODE_LSEEK based on llseek function [v2,4/8] fs: check FMODE_LSEEK to control internal pipe splicing [v2,5/8] fs: do not compare against ->llseek [v2,6/8] fs: remove no_llseek [v2,7/8] dma-buf: remove useless FMODE_LSEEK flag [v2,8/8] vfio: do not set FMODE_LSEEK flag

[v2,0/8] cleanup llseek and splice

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