From patchwork Sat Jun 25 11:01:07 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Jason A. Donenfeld" X-Patchwork-Id: 12895318 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9C27EC43334 for ; Sat, 25 Jun 2022 11:01:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232296AbiFYLB0 (ORCPT ); Sat, 25 Jun 2022 07:01:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33772 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231768AbiFYLBZ (ORCPT ); Sat, 25 Jun 2022 07:01:25 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D7A8033E10; Sat, 25 Jun 2022 04:01:24 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 559E16118D; Sat, 25 Jun 2022 11:01:24 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 18F90C3411C; Sat, 25 Jun 2022 11:01:23 +0000 (UTC) Authentication-Results: smtp.kernel.org; dkim=pass (1024-bit key) header.d=zx2c4.com header.i=@zx2c4.com header.b="j44E2yAA" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=zx2c4.com; s=20210105; t=1656154881; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=YJIW6iV4R7B7BD9c90hEDSf00G0qR7asHZoTcz8Yq+g=; b=j44E2yAA5Z3pwhXbITnVvENIVK/SlZM5nPwB+k1bgBS5rnQKHtUUBb3xvZMtQA33VZxW2R gmmYvpOPZyqdcuVqvENjnA0HINai/7b7RmVjtvJcBuGowLKK2Uj2H9A6KgChYBj7KvyV0H UmrY3gOK2VQqmaMeo1iok4e8eLVouGQ= Received: by mail.zx2c4.com (ZX2C4 Mail Server) with ESMTPSA id de6ae465 (TLSv1.3:AEAD-AES256-GCM-SHA384:256:NO); Sat, 25 Jun 2022 11:01:21 +0000 (UTC) From: "Jason A. Donenfeld" To: linux-kernel@vger.kernel.org, viro@zeniv.linux.org.uk, Jens Axboe , linux-fsdevel@vger.kernel.org Cc: "Jason A. Donenfeld" 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 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org 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(-)