mirror_zfs/config/kernel.m4
Ned Bass f1a05fa114 Fix false ENOENT on snapshot control dentries
Lookups in the snapshot control directory for an existing snapshot
fail with ENOENT if an earlier lookup failed before the snapshot was
created.  This is because the earlier lookup causes a negative dentry
to be cached which is never invalidated.

The bug can be reproduced as follows (the second ls should succeed):

 $ ls /tank/.zfs/snapshot/s
 ls: cannot access /tank/.zfs/snapshot/s: No such file or directory
 $ zfs snap tank@s
 $ ls /tank/.zfs/snapshot/s
 ls: cannot access /tank/.zfs/snapshot/s: No such file or directory

To remedy this, always invalidate cached dentries in the snapshot
control directory.  Since these entries never exist on disk there is
no significant performance penalty for the extra lookups.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #1192
2013-01-16 16:28:54 -08:00

576 lines
15 KiB
Plaintext

dnl #
dnl # Default ZFS kernel configuration
dnl #
AC_DEFUN([ZFS_AC_CONFIG_KERNEL], [
ZFS_AC_KERNEL
ZFS_AC_SPL
ZFS_AC_TEST_MODULE
ZFS_AC_KERNEL_CONFIG
ZFS_AC_KERNEL_BDEV_BLOCK_DEVICE_OPERATIONS
ZFS_AC_KERNEL_TYPE_FMODE_T
ZFS_AC_KERNEL_KOBJ_NAME_LEN
ZFS_AC_KERNEL_3ARG_BLKDEV_GET
ZFS_AC_KERNEL_BLKDEV_GET_BY_PATH
ZFS_AC_KERNEL_OPEN_BDEV_EXCLUSIVE
ZFS_AC_KERNEL_INVALIDATE_BDEV_ARGS
ZFS_AC_KERNEL_BDEV_LOGICAL_BLOCK_SIZE
ZFS_AC_KERNEL_BDEV_PHYSICAL_BLOCK_SIZE
ZFS_AC_KERNEL_BIO_EMPTY_BARRIER
ZFS_AC_KERNEL_BIO_FAILFAST
ZFS_AC_KERNEL_BIO_FAILFAST_DTD
ZFS_AC_KERNEL_REQ_FAILFAST_MASK
ZFS_AC_KERNEL_BIO_END_IO_T_ARGS
ZFS_AC_KERNEL_BIO_RW_SYNC
ZFS_AC_KERNEL_BIO_RW_SYNCIO
ZFS_AC_KERNEL_REQ_SYNC
ZFS_AC_KERNEL_BLK_END_REQUEST
ZFS_AC_KERNEL_BLK_QUEUE_FLUSH
ZFS_AC_KERNEL_BLK_QUEUE_MAX_HW_SECTORS
ZFS_AC_KERNEL_BLK_QUEUE_MAX_SEGMENTS
ZFS_AC_KERNEL_BLK_QUEUE_PHYSICAL_BLOCK_SIZE
ZFS_AC_KERNEL_BLK_QUEUE_IO_OPT
ZFS_AC_KERNEL_BLK_QUEUE_NONROT
ZFS_AC_KERNEL_BLK_QUEUE_DISCARD
ZFS_AC_KERNEL_BLK_FETCH_REQUEST
ZFS_AC_KERNEL_BLK_REQUEUE_REQUEST
ZFS_AC_KERNEL_BLK_RQ_BYTES
ZFS_AC_KERNEL_BLK_RQ_POS
ZFS_AC_KERNEL_BLK_RQ_SECTORS
ZFS_AC_KERNEL_GET_DISK_RO
ZFS_AC_KERNEL_GET_GENDISK
ZFS_AC_KERNEL_RQ_IS_SYNC
ZFS_AC_KERNEL_RQ_FOR_EACH_SEGMENT
ZFS_AC_KERNEL_DISCARD_GRANULARITY
ZFS_AC_KERNEL_CONST_XATTR_HANDLER
ZFS_AC_KERNEL_XATTR_HANDLER_GET
ZFS_AC_KERNEL_XATTR_HANDLER_SET
ZFS_AC_KERNEL_SHOW_OPTIONS
ZFS_AC_KERNEL_FSYNC
ZFS_AC_KERNEL_EVICT_INODE
ZFS_AC_KERNEL_DIRTY_INODE_WITH_FLAGS
ZFS_AC_KERNEL_NR_CACHED_OBJECTS
ZFS_AC_KERNEL_FREE_CACHED_OBJECTS
ZFS_AC_KERNEL_FALLOCATE
ZFS_AC_KERNEL_MKDIR_UMODE_T
ZFS_AC_KERNEL_LOOKUP_NAMEIDATA
ZFS_AC_KERNEL_CREATE_NAMEIDATA
ZFS_AC_KERNEL_TRUNCATE_RANGE
ZFS_AC_KERNEL_AUTOMOUNT
ZFS_AC_KERNEL_ENCODE_FH_WITH_INODE
ZFS_AC_KERNEL_COMMIT_METADATA
ZFS_AC_KERNEL_CLEAR_INODE
ZFS_AC_KERNEL_INSERT_INODE_LOCKED
ZFS_AC_KERNEL_D_MAKE_ROOT
ZFS_AC_KERNEL_D_OBTAIN_ALIAS
ZFS_AC_KERNEL_D_SET_D_OP
ZFS_AC_KERNEL_D_REVALIDATE_NAMEIDATA
ZFS_AC_KERNEL_CONST_DENTRY_OPERATIONS
ZFS_AC_KERNEL_CHECK_DISK_SIZE_CHANGE
ZFS_AC_KERNEL_TRUNCATE_SETSIZE
ZFS_AC_KERNEL_6ARGS_SECURITY_INODE_INIT_SECURITY
ZFS_AC_KERNEL_CALLBACK_SECURITY_INODE_INIT_SECURITY
ZFS_AC_KERNEL_MOUNT_NODEV
ZFS_AC_KERNEL_SHRINK
ZFS_AC_KERNEL_BDI
ZFS_AC_KERNEL_BDI_SETUP_AND_REGISTER
ZFS_AC_KERNEL_SET_NLINK
ZFS_AC_KERNEL_ELEVATOR_CHANGE
ZFS_AC_KERNEL_5ARG_SGET
AS_IF([test "$LINUX_OBJ" != "$LINUX"], [
KERNELMAKE_PARAMS="$KERNELMAKE_PARAMS O=$LINUX_OBJ"
])
AC_SUBST(KERNELMAKE_PARAMS)
dnl # -Wall -fno-strict-aliasing -Wstrict-prototypes and other
dnl # compiler options are added by the kernel build system.
KERNELCPPFLAGS="$KERNELCPPFLAGS $NO_UNUSED_BUT_SET_VARIABLE"
KERNELCPPFLAGS="$KERNELCPPFLAGS -DHAVE_SPL -D_KERNEL"
KERNELCPPFLAGS="$KERNELCPPFLAGS -DTEXT_DOMAIN=\\\"zfs-linux-kernel\\\""
AC_SUBST(KERNELCPPFLAGS)
])
dnl #
dnl # Detect name used for Module.symvers file in kernel
dnl #
AC_DEFUN([ZFS_AC_MODULE_SYMVERS], [
modpost=$LINUX/scripts/Makefile.modpost
AC_MSG_CHECKING([kernel file name for module symbols])
AS_IF([test "x$enable_linux_builtin" != xyes -a -f "$modpost"], [
AS_IF([grep -q Modules.symvers $modpost], [
LINUX_SYMBOLS=Modules.symvers
], [
LINUX_SYMBOLS=Module.symvers
])
AS_IF([test ! -f "$LINUX_OBJ/$LINUX_SYMBOLS"], [
AC_MSG_ERROR([
*** Please make sure the kernel devel package for your distribution
*** is installed. If your building with a custom kernel make sure the
*** kernel is configured, built, and the '--with-linux=PATH' configure
*** option refers to the location of the kernel source.])
])
], [
LINUX_SYMBOLS=NONE
])
AC_MSG_RESULT($LINUX_SYMBOLS)
AC_SUBST(LINUX_SYMBOLS)
])
dnl #
dnl # Detect the kernel to be built against
dnl #
AC_DEFUN([ZFS_AC_KERNEL], [
AC_ARG_WITH([linux],
AS_HELP_STRING([--with-linux=PATH],
[Path to kernel source]),
[kernelsrc="$withval"])
AC_ARG_WITH(linux-obj,
AS_HELP_STRING([--with-linux-obj=PATH],
[Path to kernel build objects]),
[kernelbuild="$withval"])
AC_MSG_CHECKING([kernel source directory])
AS_IF([test -z "$kernelsrc"], [
AS_IF([test -e "/lib/modules/$(uname -r)/source"], [
headersdir="/lib/modules/$(uname -r)/source"
sourcelink=$(readlink -f "$headersdir")
], [test -e "/lib/modules/$(uname -r)/build"], [
headersdir="/lib/modules/$(uname -r)/build"
sourcelink=$(readlink -f "$headersdir")
], [
sourcelink=$(ls -1d /usr/src/kernels/* \
/usr/src/linux-* \
2>/dev/null | grep -v obj | tail -1)
])
AS_IF([test -n "$sourcelink" && test -e ${sourcelink}], [
kernelsrc=`readlink -f ${sourcelink}`
], [
kernelsrc="[Not found]"
])
], [
AS_IF([test "$kernelsrc" = "NONE"], [
kernsrcver=NONE
])
])
AC_MSG_RESULT([$kernelsrc])
AS_IF([test ! -d "$kernelsrc"], [
AC_MSG_ERROR([
*** Please make sure the kernel devel package for your distribution
*** is installed then try again. If that fails you can specify the
*** location of the kernel source with the '--with-linux=PATH' option.])
])
AC_MSG_CHECKING([kernel build directory])
AS_IF([test -z "$kernelbuild"], [
AS_IF([test -e "/lib/modules/$(uname -r)/build"], [
kernelbuild=`readlink -f /lib/modules/$(uname -r)/build`
], [test -d ${kernelsrc}-obj/${target_cpu}/${target_cpu}], [
kernelbuild=${kernelsrc}-obj/${target_cpu}/${target_cpu}
], [test -d ${kernelsrc}-obj/${target_cpu}/default], [
kernelbuild=${kernelsrc}-obj/${target_cpu}/default
], [test -d `dirname ${kernelsrc}`/build-${target_cpu}], [
kernelbuild=`dirname ${kernelsrc}`/build-${target_cpu}
], [
kernelbuild=${kernelsrc}
])
])
AC_MSG_RESULT([$kernelbuild])
AC_MSG_CHECKING([kernel source version])
utsrelease1=$kernelbuild/include/linux/version.h
utsrelease2=$kernelbuild/include/linux/utsrelease.h
utsrelease3=$kernelbuild/include/generated/utsrelease.h
AS_IF([test -r $utsrelease1 && fgrep -q UTS_RELEASE $utsrelease1], [
utsrelease=linux/version.h
], [test -r $utsrelease2 && fgrep -q UTS_RELEASE $utsrelease2], [
utsrelease=linux/utsrelease.h
], [test -r $utsrelease3 && fgrep -q UTS_RELEASE $utsrelease3], [
utsrelease=generated/utsrelease.h
])
AS_IF([test "$utsrelease"], [
kernsrcver=`(echo "#include <$utsrelease>";
echo "kernsrcver=UTS_RELEASE") |
cpp -I $kernelbuild/include |
grep "^kernsrcver=" | cut -d \" -f 2`
AS_IF([test -z "$kernsrcver"], [
AC_MSG_RESULT([Not found])
AC_MSG_ERROR([*** Cannot determine kernel version.])
])
], [
AC_MSG_RESULT([Not found])
if test "x$enable_linux_builtin" != xyes; then
AC_MSG_ERROR([*** Cannot find UTS_RELEASE definition.])
else
AC_MSG_ERROR([
*** Cannot find UTS_RELEASE definition.
*** Please run 'make prepare' inside the kernel source tree.])
fi
])
AC_MSG_RESULT([$kernsrcver])
LINUX=${kernelsrc}
LINUX_OBJ=${kernelbuild}
LINUX_VERSION=${kernsrcver}
AC_SUBST(LINUX)
AC_SUBST(LINUX_OBJ)
AC_SUBST(LINUX_VERSION)
ZFS_AC_MODULE_SYMVERS
])
dnl #
dnl # Detect name used for the additional SPL Module.symvers file. If one
dnl # does not exist this is likely because the SPL has been configured
dnl # but not built. The '--with-spl-timeout' option can be passed
dnl # to pause here, waiting for the file to appear from a concurrently
dnl # building SPL package. If the file does not appear in time, a good
dnl # guess is made as to what this file will be named based on what it
dnl # is named in the kernel build products. This file will first be
dnl # used at link time so if the guess is wrong the build will fail
dnl # then. This unfortunately means the ZFS package does not contain a
dnl # reliable mechanism to detect symbols exported by the SPL at
dnl # configure time.
dnl #
AC_DEFUN([ZFS_AC_SPL_MODULE_SYMVERS], [
AC_ARG_WITH([spl-timeout],
AS_HELP_STRING([--with-spl-timeout=SECS],
[Wait SECS for symvers file to appear @<:@default=0@:>@]),
[timeout="$withval"], [timeout=0])
AC_MSG_CHECKING([spl file name for module symbols])
SPL_SYMBOLS=NONE
while true; do
AS_IF([test -r $SPL_OBJ/Module.symvers], [
SPL_SYMBOLS=Module.symvers
], [test -r $SPL_OBJ/Modules.symvers], [
SPL_SYMBOLS=Modules.symvers
], [test -r $SPL_OBJ/module/Module.symvers], [
SPL_SYMBOLS=Module.symvers
], [test -r $SPL_OBJ/module/Modules.symvers], [
SPL_SYMBOLS=Modules.symvers
])
AS_IF([test $SPL_SYMBOLS != NONE -o $timeout -le 0], [
break;
], [
sleep 1
timeout=$((timeout-1))
])
done
AS_IF([test "$SPL_SYMBOLS" = NONE], [
SPL_SYMBOLS=$LINUX_SYMBOLS
])
AC_MSG_RESULT([$SPL_SYMBOLS])
AC_SUBST(SPL_SYMBOLS)
])
dnl #
dnl # Detect the SPL module to be built against
dnl #
AC_DEFUN([ZFS_AC_SPL], [
AC_ARG_WITH([spl],
AS_HELP_STRING([--with-spl=PATH],
[Path to spl source]),
[splsrc="$withval"])
AC_ARG_WITH([spl-obj],
AS_HELP_STRING([--with-spl-obj=PATH],
[Path to spl build objects]),
[splbuild="$withval"])
AC_MSG_CHECKING([spl source directory])
AS_IF([test -z "$splsrc"], [
dnl #
dnl # Look in the standard development package location
dnl #
sourcelink=`ls -1d /usr/src/spl-*/${LINUX_VERSION} \
2>/dev/null | tail -1`
dnl #
dnl # Look in the DKMS source location
dnl #
AS_IF([test -z "$sourcelink" || test ! -e $sourcelink/spl_config.h], [
sourcelink=`ls -1d /var/lib/dkms/spl/*/build \
2>/dev/null | tail -1`
])
dnl #
dnl # Look in the parent directory
dnl #
AS_IF([test -z "$sourcelink" || test ! -e $sourcelink/spl_config.h], [
sourcelink=../spl
])
dnl #
dnl # Look in the kernel directory
dnl #
AS_IF([test -z "$sourcelink" || test ! -e $sourcelink/spl_config.h], [
sourcelink="$LINUX"
])
AS_IF([test -e $sourcelink/spl_config.h], [
splsrc=`readlink -f ${sourcelink}`
], [
AC_MSG_RESULT([Not found])
AC_MSG_ERROR([
*** Please make sure the spl devel package for your distribution
*** is installed then try again. If that fails you can specify the
*** location of the spl source with the '--with-spl=PATH' option.])
])
], [
AS_IF([test "$splsrc" = "NONE"], [
splbuild=NONE
splsrcver=NONE
])
])
AC_MSG_RESULT([$splsrc])
AC_MSG_CHECKING([spl build directory])
AS_IF([test -z "$splbuild"], [
splbuild=${splsrc}
])
AC_MSG_RESULT([$splbuild])
AC_MSG_CHECKING([spl source version])
AS_IF([test -r $splbuild/spl_config.h &&
fgrep -q SPL_META_VERSION $splbuild/spl_config.h], [
splsrcver=`(echo "#include <spl_config.h>";
echo "splsrcver=SPL_META_VERSION-SPL_META_RELEASE") |
cpp -I $splbuild |
grep "^splsrcver=" | tr -d \" | cut -d= -f2`
])
AS_IF([test -z "$splsrcver"], [
AC_MSG_RESULT([Not found])
AC_MSG_ERROR([
*** Cannot determine the version of the spl source.
*** Please prepare the spl source before running this script])
])
AC_MSG_RESULT([$splsrcver])
SPL=${splsrc}
SPL_OBJ=${splbuild}
SPL_VERSION=${splsrcver}
AC_SUBST(SPL)
AC_SUBST(SPL_OBJ)
AC_SUBST(SPL_VERSION)
ZFS_AC_SPL_MODULE_SYMVERS
])
dnl #
dnl # Basic toolchain sanity check.
dnl #
AC_DEFUN([ZFS_AC_TEST_MODULE],
[AC_MSG_CHECKING([whether modules can be built])
ZFS_LINUX_TRY_COMPILE([],[],[
AC_MSG_RESULT([yes])
],[
AC_MSG_RESULT([no])
if test "x$enable_linux_builtin" != xyes; then
AC_MSG_ERROR([*** Unable to build an empty module.])
else
AC_MSG_ERROR([
*** Unable to build an empty module.
*** Please run 'make scripts' inside the kernel source tree.])
fi
])
])
dnl #
dnl # Certain kernel build options are not supported. These must be
dnl # detected at configure time and cause a build failure. Otherwise
dnl # modules may be successfully built that behave incorrectly.
dnl #
AC_DEFUN([ZFS_AC_KERNEL_CONFIG], [
AS_IF([test "$ZFS_META_LICENSE" = GPL], [
AC_DEFINE([HAVE_GPL_ONLY_SYMBOLS], [1],
[Define to 1 if licensed under the GPL])
])
ZFS_AC_KERNEL_CONFIG_DEBUG_LOCK_ALLOC
])
dnl #
dnl # Check CONFIG_DEBUG_LOCK_ALLOC
dnl #
dnl # This is typically only set for debug kernels because it comes with
dnl # a performance penalty. However, when it is set it maps the non-GPL
dnl # symbol mutex_lock() to the GPL-only mutex_lock_nested() symbol.
dnl # This will cause a failure at link time which we'd rather know about
dnl # at compile time.
dnl #
dnl # Since we plan to pursue making mutex_lock_nested() a non-GPL symbol
dnl # with the upstream community we add a check to detect this case.
dnl #
AC_DEFUN([ZFS_AC_KERNEL_CONFIG_DEBUG_LOCK_ALLOC], [
ZFS_LINUX_CONFIG([DEBUG_LOCK_ALLOC], [
AC_MSG_CHECKING([whether mutex_lock() is GPL-only])
tmp_flags="$EXTRA_KCFLAGS"
ZFS_LINUX_TRY_COMPILE([
#include <linux/module.h>
#include <linux/mutex.h>
MODULE_LICENSE("$ZFS_META_LICENSE");
],[
struct mutex lock;
mutex_init(&lock);
mutex_lock(&lock);
mutex_unlock(&lock);
],[
AC_MSG_RESULT(no)
],[
AC_MSG_RESULT(yes)
AC_MSG_ERROR([
*** Kernel built with CONFIG_DEBUG_LOCK_ALLOC which is incompatible
*** with the CDDL license and will prevent the module linking stage
*** from succeeding. You must rebuild your kernel without this
*** option enabled.])
])
EXTRA_KCFLAGS="$tmp_flags"
], [])
])
dnl #
dnl # ZFS_LINUX_CONFTEST
dnl #
AC_DEFUN([ZFS_LINUX_CONFTEST], [
cat confdefs.h - <<_ACEOF >conftest.c
$1
_ACEOF
])
dnl #
dnl # ZFS_LANG_PROGRAM(C)([PROLOGUE], [BODY])
dnl #
m4_define([ZFS_LANG_PROGRAM], [
$1
int
main (void)
{
dnl Do *not* indent the following line: there may be CPP directives.
dnl Don't move the `;' right after for the same reason.
$2
;
return 0;
}
])
dnl #
dnl # ZFS_LINUX_COMPILE_IFELSE / like AC_COMPILE_IFELSE
dnl #
AC_DEFUN([ZFS_LINUX_COMPILE_IFELSE], [
m4_ifvaln([$1], [ZFS_LINUX_CONFTEST([$1])])
rm -Rf build && mkdir -p build && touch build/conftest.mod.c
echo "obj-m := conftest.o" >build/Makefile
modpost_flag=''
test "x$enable_linux_builtin" = xyes && modpost_flag='modpost=true' # fake modpost stage
AS_IF(
[AC_TRY_COMMAND(cp conftest.c build && make [$2] -C $LINUX_OBJ EXTRA_CFLAGS="-Werror-implicit-function-declaration $EXTRA_KCFLAGS" $ARCH_UM M=$PWD/build $modpost_flag) >/dev/null && AC_TRY_COMMAND([$3])],
[$4],
[_AC_MSG_LOG_CONFTEST m4_ifvaln([$5],[$5])]
)
rm -Rf build
])
dnl #
dnl # ZFS_LINUX_TRY_COMPILE like AC_TRY_COMPILE
dnl #
AC_DEFUN([ZFS_LINUX_TRY_COMPILE],
[ZFS_LINUX_COMPILE_IFELSE(
[AC_LANG_SOURCE([ZFS_LANG_PROGRAM([[$1]], [[$2]])])],
[modules],
[test -s build/conftest.o],
[$3], [$4])
])
dnl #
dnl # ZFS_LINUX_CONFIG
dnl #
AC_DEFUN([ZFS_LINUX_CONFIG],
[AC_MSG_CHECKING([whether Linux was built with CONFIG_$1])
ZFS_LINUX_TRY_COMPILE([
#include <linux/module.h>
],[
#ifndef CONFIG_$1
#error CONFIG_$1 not #defined
#endif
],[
AC_MSG_RESULT([yes])
$2
],[
AC_MSG_RESULT([no])
$3
])
])
dnl #
dnl # ZFS_CHECK_SYMBOL_EXPORT
dnl # check symbol exported or not
dnl #
AC_DEFUN([ZFS_CHECK_SYMBOL_EXPORT], [
grep -q -E '[[[:space:]]]$1[[[:space:]]]' \
$LINUX_OBJ/$LINUX_SYMBOLS 2>/dev/null
rc=$?
if test $rc -ne 0; then
export=0
for file in $2; do
grep -q -E "EXPORT_SYMBOL.*($1)" \
"$LINUX/$file" 2>/dev/null
rc=$?
if test $rc -eq 0; then
export=1
break;
fi
done
if test $export -eq 0; then :
$4
else :
$3
fi
else :
$3
fi
])
dnl #
dnl # ZFS_LINUX_TRY_COMPILE_SYMBOL
dnl # like ZFS_LINUX_TRY_COMPILE, except ZFS_CHECK_SYMBOL_EXPORT
dnl # is called if not compiling for builtin
dnl #
AC_DEFUN([ZFS_LINUX_TRY_COMPILE_SYMBOL], [
ZFS_LINUX_TRY_COMPILE([$1], [$2], [rc=0], [rc=1])
if test $rc -ne 0; then :
$6
else
if test "x$enable_linux_builtin" != xyes; then
ZFS_CHECK_SYMBOL_EXPORT([$3], [$4], [rc=0], [rc=1])
fi
if test $rc -ne 0; then :
$6
else :
$5
fi
fi
])