[PATCH v2 0/8] cleanup llseek and splice

From: Jason A. Donenfeld
Date: Sat Jun 25 2022 - 07:01:30 EST

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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(-)

--
2.35.1

Next message: Jason A. Donenfeld: "[PATCH v2 1/8] ksmbd: use vfs_llseek instead of dereferencing NULL"
Previous message: Lad, Prabhakar: "Re: [PATCH v5 2/5] irqchip: Add RZ/G2L IA55 Interrupt Controller driver"
Next in thread: Jason A. Donenfeld: "[PATCH v2 1/8] ksmbd: use vfs_llseek instead of dereferencing NULL"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]