]> granicus.if.org Git - zfs/commitdiff
Retire .write/.read file operations
authorChunwei Chen <tuxoko@gmail.com>
Fri, 27 Jan 2017 18:43:39 +0000 (10:43 -0800)
committerBrian Behlendorf <behlendorf1@llnl.gov>
Fri, 27 Jan 2017 18:43:39 +0000 (10:43 -0800)
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 <behlendorf1@llnl.gov>
Signed-off-by: Chunwei Chen <david.chen@osnexus.com>
Closes #5587
Closes #5673

config/kernel-vfs-rw-iterate.m4
config/kernel.m4
module/zfs/zpl_file.c
tests/runfiles/linux.run
tests/zfs-tests/tests/functional/large_files/Makefile.am
tests/zfs-tests/tests/functional/large_files/large_files_002_pos.ksh [new file with mode: 0755]

index f8dc4222968680db788ee5b507875e26489f8475..af44beb7bcfce1633371f83ec166c8e8dab93374 100644 (file)
@@ -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 <linux/fs.h>
+
+       ],[
+               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)
+       ])
+])
index 980d2801f6df020041b8412626cf487221d4c0df..afb0cc7faad68e5a82148f4b105264eaafdd7db2 100644 (file)
@@ -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
index 356fa78f83afd4728cdecfa54e32e4ace47f2a5c..75a3b55d1f8931a76c37fd3ea8d8d642a715bf16 100644 (file)
@@ -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,
index f09001d24ed4658417ad0bba66e79036ada1ca8e..0a8198236fbfbcbe09adeb544df894688f604e52 100644 (file)
@@ -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]
index d78ea472288739a00691ce91ee6746bea41d41ed..0e471533090c8ec449893782f29984408ec5660b 100644 (file)
@@ -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 (executable)
index 0000000..152fe2e
--- /dev/null
@@ -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 $TESTDIR/ulimit_trunc_file
+
+# Verify 'ulimit -f <size>' works
+log_must ulimit -f 1024
+log_mustnot sh -c 'dd if=/dev/zero of=$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"