[RFC] stop using ->read and ->write for kernel access v3

From: Christoph Hellwig
Date: Wed Jul 01 2020 - 16:12:20 EST


Hi Al and Linus (and Stephen, see below),

as part of removing set_fs entirely (for which I have a working
prototype), we need to stop calling ->read and ->write with kernel
pointers under set_fs.

This removes the option to call ->read and ->write with kernel pointers
entirely. The replacements are the existing ->read_iter and ->write_iter
methods which cope with kvecs and kernel pointers just fine and are
already used by many instances including all the "real" file systems.

A git branch is available here:

git://git.infradead.org/users/hch/misc.git set_fs-rw

Gitweb:

http://git.infradead.org/users/hch/misc.git/shortlog/refs/heads/set_fs-rw

Given that this has been out and cooking for a while, is there a chance to
add the above as a temp branch to linux-next to get a little more exposure
until Al reviews it and (hopefully) picks it up?

Changes since v2:
- merged with the prep series
- simplify warn_unsupported()
- make splice do the right thing on files with the iter ops by
default instead of requiring manual setup

Changes since v1:
- drop the read_uptr/write_uptr methods
- pick up a bunch of sysctl fixes and iter conversion from Matthew Wilcox

Diffstat:
Documentation/filesystems/seq_file.rst | 2
Documentation/process/clang-format.rst | 4
Documentation/translations/it_IT/process/clang-format.rst | 4
arch/alpha/kernel/srm_env.c | 2
arch/arm/mm/alignment.c | 2
arch/arm/mm/ptdump_debugfs.c | 2
arch/arm64/kvm/vgic/vgic-debug.c | 2
arch/c6x/platforms/pll.c | 2
arch/mips/cavium-octeon/oct_ilm.c | 2
arch/mips/kernel/segment.c | 2
arch/mips/ralink/bootrom.c | 2
arch/powerpc/kernel/rtas-proc.c | 10
arch/powerpc/kvm/book3s_xive_native.c | 2
arch/powerpc/kvm/timing.c | 2
arch/powerpc/mm/numa.c | 2
arch/powerpc/mm/ptdump/bats.c | 2
arch/powerpc/mm/ptdump/hashpagetable.c | 2
arch/powerpc/mm/ptdump/ptdump.c | 2
arch/powerpc/mm/ptdump/segment_regs.c | 2
arch/powerpc/platforms/cell/spufs/file.c | 8
arch/powerpc/platforms/pseries/hvCall_inst.c | 2
arch/powerpc/platforms/pseries/lpar.c | 4
arch/powerpc/platforms/pseries/lparcfg.c | 2
arch/s390/kernel/diag.c | 2
arch/s390/mm/dump_pagetables.c | 2
arch/s390/pci/pci_debug.c | 2
arch/sh/mm/alignment.c | 2
arch/sh/mm/asids-debugfs.c | 2
arch/sh/mm/cache-debugfs.c | 2
arch/sh/mm/pmb.c | 2
arch/sh/mm/tlb-debugfs.c | 2
arch/sparc/kernel/led.c | 2
arch/um/kernel/exitcode.c | 2
arch/um/kernel/process.c | 2
arch/x86/kernel/cpu/mce/severity.c | 2
arch/x86/kernel/cpu/mtrr/if.c | 2
arch/x86/mm/pat/memtype.c | 2
arch/x86/mm/pat/set_memory.c | 2
arch/x86/platform/uv/tlb_uv.c | 2
arch/x86/xen/p2m.c | 2
block/blk-mq-debugfs.c | 2
drivers/acpi/battery.c | 2
drivers/acpi/proc.c | 2
drivers/base/power/wakeup.c | 2
drivers/block/aoe/aoeblk.c | 2
drivers/block/drbd/drbd_debugfs.c | 10
drivers/block/nbd.c | 4
drivers/block/pktcdvd.c | 2
drivers/block/rsxx/core.c | 4
drivers/bus/mvebu-mbus.c | 4
drivers/char/tpm/eventlog/common.c | 2
drivers/crypto/allwinner/sun8i-ce/sun8i-ce-core.c | 2
drivers/crypto/allwinner/sun8i-ss/sun8i-ss-core.c | 2
drivers/crypto/amlogic/amlogic-gxl-core.c | 2
drivers/crypto/caam/dpseci-debugfs.c | 2
drivers/crypto/cavium/zip/zip_main.c | 6
drivers/crypto/hisilicon/qm.c | 2
drivers/crypto/qat/qat_common/adf_cfg.c | 2
drivers/crypto/qat/qat_common/adf_transport_debug.c | 4
drivers/firmware/tegra/bpmp-debugfs.c | 2
drivers/gpio/gpiolib.c | 2
drivers/gpu/drm/amd/amdkfd/kfd_debugfs.c | 4
drivers/gpu/drm/arm/display/komeda/komeda_dev.c | 2
drivers/gpu/drm/arm/malidp_drv.c | 2
drivers/gpu/drm/armada/armada_debugfs.c | 2
drivers/gpu/drm/drm_debugfs.c | 6
drivers/gpu/drm/drm_debugfs_crc.c | 2
drivers/gpu/drm/drm_mipi_dbi.c | 2
drivers/gpu/drm/i915/display/intel_display_debugfs.c | 16
drivers/gpu/drm/i915/gt/debugfs_gt.h | 2
drivers/gpu/drm/i915/i915_debugfs_params.c | 12
drivers/gpu/drm/msm/disp/dpu1/dpu_core_irq.c | 2
drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c | 4
drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c | 2
drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c | 4
drivers/gpu/drm/msm/msm_debugfs.c | 2
drivers/gpu/drm/nouveau/nouveau_debugfs.c | 2
drivers/gpu/drm/omapdrm/dss/dss.c | 2
drivers/gpu/host1x/debug.c | 4
drivers/gpu/vga/vga_switcheroo.c | 2
drivers/hid/hid-picolcd_debugfs.c | 2
drivers/hid/hid-wiimote-debug.c | 2
drivers/hwmon/dell-smm-hwmon.c | 2
drivers/ide/ide-proc.c | 4
drivers/infiniband/hw/cxgb4/device.c | 4
drivers/infiniband/hw/qib/qib_debugfs.c | 2
drivers/infiniband/ulp/ipoib/ipoib_fs.c | 4
drivers/input/input.c | 4
drivers/macintosh/via-pmu.c | 2
drivers/md/bcache/closure.c | 2
drivers/md/md.c | 2
drivers/media/cec/core/cec-core.c | 2
drivers/media/pci/saa7164/saa7164-core.c | 2
drivers/memory/emif.c | 4
drivers/memory/tegra/tegra124-emc.c | 2
drivers/memory/tegra/tegra186-emc.c | 2
drivers/memory/tegra/tegra20-emc.c | 2
drivers/memory/tegra/tegra30-emc.c | 2
drivers/mfd/ab3100-core.c | 2
drivers/mfd/ab3100-otp.c | 2
drivers/mfd/ab8500-debugfs.c | 14
drivers/mfd/tps65010.c | 2
drivers/misc/habanalabs/debugfs.c | 2
drivers/misc/sgi-gru/gruprocfs.c | 6
drivers/mmc/core/mmc_test.c | 2
drivers/mtd/mtdcore.c | 4
drivers/mtd/ubi/debug.c | 2
drivers/net/ethernet/chelsio/cxgb4/cxgb4_debugfs.c | 38 +-
drivers/net/ethernet/chelsio/cxgb4/l2t.c | 2
drivers/net/ethernet/chelsio/cxgb4vf/cxgb4vf_main.c | 8
drivers/net/ethernet/freescale/dpaa2/dpaa2-eth-debugfs.c | 6
drivers/net/ethernet/intel/fm10k/fm10k_debugfs.c | 2
drivers/net/ethernet/marvell/octeontx2/af/rvu_debugfs.c | 2
drivers/net/wireless/ath/ath5k/debug.c | 2
drivers/net/wireless/ath/wil6210/debugfs.c | 14
drivers/net/wireless/broadcom/brcm80211/brcmsmac/debug.c | 2
drivers/net/wireless/intel/ipw2x00/libipw_module.c | 2
drivers/net/wireless/intel/iwlwifi/fw/debugfs.c | 2
drivers/net/wireless/intel/iwlwifi/pcie/trans.c | 2
drivers/net/wireless/intersil/hostap/hostap_download.c | 2
drivers/net/wireless/mediatek/mt76/mt7603/debugfs.c | 2
drivers/net/wireless/mediatek/mt76/mt7615/debugfs.c | 2
drivers/net/wireless/mediatek/mt76/mt76x02_debugfs.c | 4
drivers/net/wireless/mediatek/mt76/mt7915/debugfs.c | 4
drivers/net/wireless/mediatek/mt7601u/debugfs.c | 4
drivers/net/wireless/realtek/rtlwifi/debug.c | 2
drivers/net/wireless/realtek/rtw88/debug.c | 4
drivers/net/wireless/rsi/rsi_91x_debugfs.c | 4
drivers/net/xen-netback/xenbus.c | 2
drivers/nvme/host/fabrics.c | 2
drivers/parisc/led.c | 2
drivers/pci/controller/pci-tegra.c | 2
drivers/platform/x86/asus-wmi.c | 2
drivers/platform/x86/intel_pmc_core.c | 2
drivers/platform/x86/intel_telemetry_debugfs.c | 4
drivers/platform/x86/thinkpad_acpi.c | 2
drivers/platform/x86/toshiba_acpi.c | 8
drivers/pnp/pnpbios/proc.c | 2
drivers/power/supply/da9030_battery.c | 2
drivers/pwm/core.c | 2
drivers/ras/cec.c | 2
drivers/ras/debugfs.c | 2
drivers/s390/block/dasd.c | 2
drivers/s390/block/dasd_proc.c | 2
drivers/s390/cio/blacklist.c | 2
drivers/s390/cio/qdio_debug.c | 2
drivers/scsi/hisi_sas/hisi_sas_main.c | 32 -
drivers/scsi/qedf/qedf_dbg.h | 2
drivers/scsi/qedi/qedi_dbg.h | 2
drivers/scsi/qla2xxx/qla_dfs.c | 12
drivers/scsi/scsi_devinfo.c | 2
drivers/scsi/scsi_proc.c | 4
drivers/scsi/sg.c | 4
drivers/scsi/snic/snic_debugfs.c | 4
drivers/sh/intc/virq-debugfs.c | 2
drivers/soc/qcom/cmd-db.c | 2
drivers/soc/qcom/socinfo.c | 4
drivers/soc/ti/knav_dma.c | 2
drivers/soc/ti/knav_qmss_queue.c | 2
drivers/staging/rtl8192u/ieee80211/ieee80211_module.c | 2
drivers/staging/vc04_services/interface/vchiq_arm/vchiq_debugfs.c | 4
drivers/usb/chipidea/debug.c | 4
drivers/usb/dwc2/debugfs.c | 2
drivers/usb/dwc3/debugfs.c | 8
drivers/usb/gadget/function/rndis.c | 2
drivers/usb/gadget/udc/lpc32xx_udc.c | 2
drivers/usb/gadget/udc/renesas_usb3.c | 2
drivers/usb/host/xhci-debugfs.c | 6
drivers/usb/mtu3/mtu3_debugfs.c | 8
drivers/usb/musb/musb_debugfs.c | 4
drivers/video/fbdev/via/viafbdev.c | 14
drivers/visorbus/visorbus_main.c | 2
drivers/xen/xenfs/xensyms.c | 2
fs/adfs/file.c | 1
fs/affs/file.c | 1
fs/afs/file.c | 1
fs/autofs/waitq.c | 2
fs/bfs/file.c | 1
fs/block_dev.c | 2
fs/btrfs/file.c | 1
fs/cachefiles/rdwr.c | 2
fs/ceph/file.c | 2
fs/cifs/cifs_debug.c | 14
fs/cifs/cifsfs.c | 12
fs/cifs/dfs_cache.c | 2
fs/coda/file.c | 1
fs/cramfs/inode.c | 1
fs/debugfs/file.c | 4
fs/dlm/debug_fs.c | 8
fs/ecryptfs/file.c | 1
fs/exfat/file.c | 2
fs/ext2/file.c | 2
fs/ext4/file.c | 2
fs/f2fs/file.c | 2
fs/fat/file.c | 2
fs/fscache/object-list.c | 2
fs/fuse/file.c | 2
fs/gfs2/file.c | 2
fs/gfs2/glock.c | 6
fs/hfs/inode.c | 1
fs/hfsplus/inode.c | 1
fs/hostfs/hostfs_kern.c | 1
fs/hpfs/file.c | 1
fs/jbd2/journal.c | 2
fs/jffs2/file.c | 1
fs/jfs/file.c | 2
fs/jfs/jfs_debug.c | 2
fs/minix/file.c | 1
fs/nfs/file.c | 2
fs/nfs/nfs4file.c | 2
fs/nfsd/nfs4state.c | 4
fs/nfsd/nfsctl.c | 12
fs/nfsd/stats.c | 2
fs/nilfs2/file.c | 1
fs/ntfs/file.c | 1
fs/ocfs2/cluster/netdebug.c | 6
fs/ocfs2/dlm/dlmdebug.c | 2
fs/ocfs2/dlmglue.c | 2
fs/ocfs2/file.c | 4
fs/omfs/file.c | 1
fs/openpromfs/inode.c | 2
fs/orangefs/orangefs-debugfs.c | 2
fs/proc/array.c | 2
fs/proc/base.c | 24 -
fs/proc/cpuinfo.c | 2
fs/proc/fd.c | 2
fs/proc/generic.c | 4
fs/proc/inode.c | 28 +
fs/proc/proc_net.c | 4
fs/proc/proc_sysctl.c | 50 +-
fs/proc/stat.c | 2
fs/proc/task_mmu.c | 8
fs/proc/task_nommu.c | 2
fs/proc_namespace.c | 6
fs/ramfs/file-mmu.c | 2
fs/ramfs/file-nommu.c | 2
fs/read_write.c | 176 ++++++----
fs/reiserfs/file.c | 2
fs/romfs/mmap-nommu.c | 1
fs/seq_file.c | 34 +
fs/splice.c | 125 -------
fs/sysv/file.c | 1
fs/ubifs/file.c | 2
fs/udf/file.c | 1
fs/ufs/file.c | 1
fs/vboxsf/file.c | 1
fs/xfs/xfs_file.c | 2
fs/zonefs/super.c | 2
include/linux/bpf-cgroup.h | 2
include/linux/fs.h | 6
include/linux/proc_fs.h | 1
include/linux/seq_file.h | 7
ipc/util.c | 2
kernel/bpf/cgroup.c | 2
kernel/bpf/inode.c | 2
kernel/fail_function.c | 2
kernel/gcov/fs.c | 2
kernel/irq/debugfs.c | 2
kernel/irq/proc.c | 6
kernel/kallsyms.c | 2
kernel/kcsan/debugfs.c | 2
kernel/latencytop.c | 2
kernel/locking/lockdep_proc.c | 2
kernel/module.c | 2
kernel/profile.c | 2
kernel/sched/debug.c | 2
kernel/sched/psi.c | 6
kernel/time/test_udelay.c | 2
kernel/trace/ftrace.c | 16
kernel/trace/trace.c | 20 -
kernel/trace/trace_dynevent.c | 2
kernel/trace/trace_events.c | 10
kernel/trace/trace_events_hist.c | 4
kernel/trace/trace_events_synth.c | 2
kernel/trace/trace_events_trigger.c | 2
kernel/trace/trace_kprobe.c | 4
kernel/trace/trace_printk.c | 2
kernel/trace/trace_stack.c | 4
kernel/trace/trace_stat.c | 2
kernel/trace/trace_uprobe.c | 4
lib/debugobjects.c | 2
lib/dynamic_debug.c | 4
lib/error-inject.c | 2
lib/kunit/debugfs.c | 2
mm/kmemleak.c | 2
mm/shmem.c | 2
mm/slab_common.c | 2
mm/swapfile.c | 2
net/6lowpan/debugfs.c | 2
net/atm/mpoa_proc.c | 2
net/batman-adv/debugfs.c | 4
net/bluetooth/6lowpan.c | 2
net/bpfilter/bpfilter_kern.c | 2
net/core/pktgen.c | 6
net/hsr/hsr_debugfs.c | 2
net/ipv4/netfilter/ipt_CLUSTERIP.c | 2
net/ipv4/route.c | 4
net/l2tp/l2tp_debugfs.c | 2
net/netfilter/xt_recent.c | 2
net/sunrpc/cache.c | 4
net/sunrpc/debugfs.c | 4
net/sunrpc/rpc_pipe.c | 2
net/sunrpc/stats.c | 2
security/apparmor/apparmorfs.c | 10
security/integrity/iint.c | 14
security/integrity/ima/ima_fs.c | 6
security/selinux/selinuxfs.c | 2
security/smack/smackfs.c | 20 -
sound/core/info.c | 2
309 files changed, 678 insertions(+), 791 deletions(-)