From 933ec999511f3d29de005bfa8966ae007b161c0f Mon Sep 17 00:00:00 2001 From: Chunwei Chen Date: Fri, 27 Jan 2017 10:43:39 -0800 Subject: [PATCH] Retire .write/.read file operations The .write/.read file operations callbacks can be retired since support for .read_iter/.write_iter and .aio_read/.aio_write has been added. The vfs_write()/vfs_read() entry functions will select the correct interface for the kernel. This is desirable because all VFS write/read operations now rely on common code. This change also add the generic write checks to make sure that ulimits are enforced correctly on write. Signed-off-by: Brian Behlendorf Signed-off-by: Chunwei Chen Closes #5587 Closes #5673 --- config/kernel-vfs-rw-iterate.m4 | 21 +++++ config/kernel.m4 | 1 + module/zfs/zpl_file.c | 84 +++++++++++-------- tests/runfiles/linux.run | 5 +- .../tests/functional/large_files/Makefile.am | 3 +- .../large_files/large_files_002_pos.ksh | 55 ++++++++++++ 6 files changed, 132 insertions(+), 37 deletions(-) create mode 100755 tests/zfs-tests/tests/functional/large_files/large_files_002_pos.ksh diff --git a/config/kernel-vfs-rw-iterate.m4 b/config/kernel-vfs-rw-iterate.m4 index f8dc42229686..af44beb7bcfc 100644 --- a/config/kernel-vfs-rw-iterate.m4 +++ b/config/kernel-vfs-rw-iterate.m4 @@ -25,3 +25,24 @@ AC_DEFUN([ZFS_AC_KERNEL_VFS_RW_ITERATE], AC_MSG_RESULT(no) ]) ]) + +dnl # +dnl # Linux 4.1.x API +dnl # +AC_DEFUN([ZFS_AC_KERNEL_GENERIC_WRITE_CHECKS], + [AC_MSG_CHECKING([whether generic_write_checks() takes kiocb]) + ZFS_LINUX_TRY_COMPILE([ + #include + + ],[ + struct kiocb *iocb = NULL; + struct iov_iter *iov = NULL; + generic_write_checks(iocb, iov); + ],[ + AC_MSG_RESULT(yes) + AC_DEFINE(HAVE_GENERIC_WRITE_CHECKS_KIOCB, 1, + [generic_write_checks() takes kiocb]) + ],[ + AC_MSG_RESULT(no) + ]) +]) diff --git a/config/kernel.m4 b/config/kernel.m4 index 980d2801f6df..afb0cc7faad6 100644 --- a/config/kernel.m4 +++ b/config/kernel.m4 @@ -104,6 +104,7 @@ AC_DEFUN([ZFS_AC_CONFIG_KERNEL], [ ZFS_AC_KERNEL_LSEEK_EXECUTE ZFS_AC_KERNEL_VFS_ITERATE ZFS_AC_KERNEL_VFS_RW_ITERATE + ZFS_AC_KERNEL_GENERIC_WRITE_CHECKS ZFS_AC_KERNEL_KMAP_ATOMIC_ARGS ZFS_AC_KERNEL_FOLLOW_DOWN_ONE ZFS_AC_KERNEL_MAKE_REQUEST_FN diff --git a/module/zfs/zpl_file.c b/module/zfs/zpl_file.c index 356fa78f83af..75a3b55d1f89 100644 --- a/module/zfs/zpl_file.c +++ b/module/zfs/zpl_file.c @@ -258,21 +258,6 @@ zpl_read_common(struct inode *ip, const char *buf, size_t len, loff_t *ppos, flags, cr, 0)); } -static ssize_t -zpl_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos) -{ - cred_t *cr = CRED(); - ssize_t read; - - crhold(cr); - read = zpl_read_common(filp->f_mapping->host, buf, len, ppos, - UIO_USERSPACE, filp->f_flags, cr); - crfree(cr); - - file_accessed(filp); - return (read); -} - static ssize_t zpl_iter_read_common(struct kiocb *kiocb, const struct iovec *iovp, unsigned long nr_segs, size_t count, uio_seg_t seg, size_t skip) @@ -311,7 +296,14 @@ static ssize_t zpl_aio_read(struct kiocb *kiocb, const struct iovec *iovp, unsigned long nr_segs, loff_t pos) { - return (zpl_iter_read_common(kiocb, iovp, nr_segs, kiocb->ki_nbytes, + ssize_t ret; + size_t count; + + ret = generic_segment_checks(iovp, &nr_segs, &count, VERIFY_WRITE); + if (ret) + return (ret); + + return (zpl_iter_read_common(kiocb, iovp, nr_segs, count, UIO_USERSPACE, 0)); } #endif /* HAVE_VFS_RW_ITERATE */ @@ -349,6 +341,7 @@ zpl_write_common_iovec(struct inode *ip, const struct iovec *iovp, size_t count, return (wrote); } + inline ssize_t zpl_write_common(struct inode *ip, const char *buf, size_t len, loff_t *ppos, uio_seg_t segment, int flags, cred_t *cr) @@ -362,20 +355,6 @@ zpl_write_common(struct inode *ip, const char *buf, size_t len, loff_t *ppos, flags, cr, 0)); } -static ssize_t -zpl_write(struct file *filp, const char __user *buf, size_t len, loff_t *ppos) -{ - cred_t *cr = CRED(); - ssize_t wrote; - - crhold(cr); - wrote = zpl_write_common(filp->f_mapping->host, buf, len, ppos, - UIO_USERSPACE, filp->f_flags, cr); - crfree(cr); - - return (wrote); -} - static ssize_t zpl_iter_write_common(struct kiocb *kiocb, const struct iovec *iovp, unsigned long nr_segs, size_t count, uio_seg_t seg, size_t skip) @@ -396,16 +375,40 @@ zpl_iter_write_common(struct kiocb *kiocb, const struct iovec *iovp, static ssize_t zpl_iter_write(struct kiocb *kiocb, struct iov_iter *from) { + size_t count; ssize_t ret; uio_seg_t seg = UIO_USERSPACE; + +#ifndef HAVE_GENERIC_WRITE_CHECKS_KIOCB + struct file *file = kiocb->ki_filp; + struct address_space *mapping = file->f_mapping; + struct inode *ip = mapping->host; + int isblk = S_ISBLK(ip->i_mode); + + count = iov_iter_count(from); + ret = generic_write_checks(file, &kiocb->ki_pos, &count, isblk); +#else + /* + * XXX - ideally this check should be in the same lock region with + * write operations, so that there's no TOCTTOU race when doing + * append and someone else grow the file. + */ + ret = generic_write_checks(kiocb, from); + count = ret; +#endif + if (ret <= 0) + return (ret); + if (from->type & ITER_KVEC) seg = UIO_SYSSPACE; if (from->type & ITER_BVEC) seg = UIO_BVEC; + ret = zpl_iter_write_common(kiocb, from->iov, from->nr_segs, - iov_iter_count(from), seg, from->iov_offset); + count, seg, from->iov_offset); if (ret > 0) iov_iter_advance(from, ret); + return (ret); } #else @@ -413,7 +416,22 @@ static ssize_t zpl_aio_write(struct kiocb *kiocb, const struct iovec *iovp, unsigned long nr_segs, loff_t pos) { - return (zpl_iter_write_common(kiocb, iovp, nr_segs, kiocb->ki_nbytes, + struct file *file = kiocb->ki_filp; + struct address_space *mapping = file->f_mapping; + struct inode *ip = mapping->host; + int isblk = S_ISBLK(ip->i_mode); + size_t count; + ssize_t ret; + + ret = generic_segment_checks(iovp, &nr_segs, &count, VERIFY_READ); + if (ret) + return (ret); + + ret = generic_write_checks(file, &pos, &count, isblk); + if (ret) + return (ret); + + return (zpl_iter_write_common(kiocb, iovp, nr_segs, count, UIO_USERSPACE, 0)); } #endif /* HAVE_VFS_RW_ITERATE */ @@ -835,8 +853,6 @@ const struct file_operations zpl_file_operations = { .open = zpl_open, .release = zpl_release, .llseek = zpl_llseek, - .read = zpl_read, - .write = zpl_write, #ifdef HAVE_VFS_RW_ITERATE .read_iter = zpl_iter_read, .write_iter = zpl_iter_write, diff --git a/tests/runfiles/linux.run b/tests/runfiles/linux.run index f09001d24ed4..0a8198236fbf 100644 --- a/tests/runfiles/linux.run +++ b/tests/runfiles/linux.run @@ -458,8 +458,9 @@ tests = ['inuse_004_pos'] post = # DISABLED: needs investigation -#[tests/functional/large_files] -#tests = ['large_files_001_pos'] +# large_files_001_pos +[tests/functional/large_files] +tests = ['large_files_002_pos'] # DISABLED: needs investigation #[tests/functional/largest_pool] diff --git a/tests/zfs-tests/tests/functional/large_files/Makefile.am b/tests/zfs-tests/tests/functional/large_files/Makefile.am index d78ea4722887..0e471533090c 100644 --- a/tests/zfs-tests/tests/functional/large_files/Makefile.am +++ b/tests/zfs-tests/tests/functional/large_files/Makefile.am @@ -2,4 +2,5 @@ pkgdatadir = $(datadir)/@PACKAGE@/zfs-tests/tests/functional/large_files dist_pkgdata_SCRIPTS = \ setup.ksh \ cleanup.ksh \ - large_files_001_pos.ksh + large_files_001_pos.ksh \ + large_files_002_pos.ksh diff --git a/tests/zfs-tests/tests/functional/large_files/large_files_002_pos.ksh b/tests/zfs-tests/tests/functional/large_files/large_files_002_pos.ksh new file mode 100755 index 000000000000..152fe2e08121 --- /dev/null +++ b/tests/zfs-tests/tests/functional/large_files/large_files_002_pos.ksh @@ -0,0 +1,55 @@ +#!/bin/ksh -p +# +# CDDL HEADER START +# +# The contents of this file are subject to the terms of the +# Common Development and Distribution License (the "License"). +# You may not use this file except in compliance with the License. +# +# You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE +# or http://www.opensolaris.org/os/licensing. +# See the License for the specific language governing permissions +# and limitations under the License. +# +# When distributing Covered Code, include this CDDL HEADER in each +# file and include the License file at usr/src/OPENSOLARIS.LICENSE. +# If applicable, add the following below this CDDL HEADER, with the +# fields enclosed by brackets "[]" replaced with your own identifying +# information: Portions Copyright [yyyy] [name of copyright owner] +# +# CDDL HEADER END +# + +# +# Copyright (c) 2015 by Lawrence Livermore National Security, LLC. +# All rights reserved. +# + +. $STF_SUITE/include/libtest.shlib + +# +# DESCRIPTION: +# Verify 'ulimit -f' file size restrictions are enforced. +# +# STRATEGY: +# 1. Set ulimit file size to unlimited, verify files can be created. +# 2. Reduce ulimit file size, verify the expected error is returned. +# + +verify_runnable "both" + +log_assert "Verify 'ulimit -f' maximum file size is enforced" + +# Verify 'ulimit -f unlimited' works +log_must ulimit -f unlimited +log_must sh -c 'dd if=/dev/zero of=$TESTDIR/ulimit_write_file bs=1M count=2' +log_must sh -c '$TRUNCATE -s2M $TESTDIR/ulimit_trunc_file' +log_must $RM $TESTDIR/ulimit_write_file $TESTDIR/ulimit_trunc_file + +# Verify 'ulimit -f ' works +log_must ulimit -f 1024 +log_mustnot sh -c 'dd if=/dev/zero of=$TESTDIR/ulimit_write_file bs=1M count=2' +log_mustnot sh -c '$TRUNCATE -s2M $TESTDIR/ulimit_trunc_file' +log_must $RM $TESTDIR/ulimit_write_file $TESTDIR/ulimit_trunc_file + +log_pass "Successfully enforced 'ulimit -f' maximum file size"