Remove kallsyms_lookup_name() wrapper

After the removable of get_vmalloc_info(), the unused global memory
variables, and the optional dcache/icache shrinkers there is no
longer a need for the kallsyms compatibility code.  This allows
us to eliminate another brittle area of the code by removing the
kernel upcall this functionality depended on for older kernels.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
This commit is contained in:
Brian Behlendorf 2014-10-01 19:58:11 -04:00
parent 89a461e70c
commit 44778f4110
6 changed files with 1 additions and 209 deletions

View File

@ -28,7 +28,6 @@ AC_DEFUN([SPL_AC_CONFIG_KERNEL], [
SPL_AC_PDE_DATA
SPL_AC_MUTEX_OWNER
SPL_AC_MUTEX_OWNER_TASK_STRUCT
SPL_AC_KALLSYMS_LOOKUP_NAME
SPL_AC_USER_PATH_DIR
SPL_AC_SET_FS_PWD
SPL_AC_SET_FS_PWD_WITH_CONST
@ -47,7 +46,6 @@ AC_DEFUN([SPL_AC_CONFIG_KERNEL], [
SPL_AC_EXPORTED_RWSEM_IS_LOCKED
SPL_AC_KERNEL_FALLOCATE
SPL_AC_KERN_PATH
SPL_AC_CONFIG_KALLSYMS
SPL_AC_CONFIG_ZLIB_INFLATE
SPL_AC_CONFIG_ZLIB_DEFLATE
SPL_AC_2ARGS_ZLIB_DEFLATE_WORKSPACESIZE
@ -957,25 +955,6 @@ AC_DEFUN([SPL_AC_MUTEX_OWNER_TASK_STRUCT], [
EXTRA_KCFLAGS="$tmp_flags"
])
dnl #
dnl # 2.6.18 API change,
dnl # kallsyms_lookup_name no longer exported
dnl #
AC_DEFUN([SPL_AC_KALLSYMS_LOOKUP_NAME],
[AC_MSG_CHECKING([whether kallsyms_lookup_name() is available])
SPL_LINUX_TRY_COMPILE_SYMBOL([
#include <linux/kallsyms.h>
], [
kallsyms_lookup_name(NULL);
], [kallsyms_lookup_name], [], [
AC_MSG_RESULT(yes)
AC_DEFINE(HAVE_KALLSYMS_LOOKUP_NAME, 1,
[kallsyms_lookup_name() is available])
], [
AC_MSG_RESULT(no)
])
])
dnl #
dnl # 3.10 API change,
dnl # PDE is replaced by PDE_DATA
@ -1501,26 +1480,6 @@ AC_DEFUN([SPL_AC_KERN_PATH],
])
])
dnl #
dnl # /proc/kallsyms support,
dnl # Verify the kernel has CONFIG_KALLSYMS support enabled.
dnl #
AC_DEFUN([SPL_AC_CONFIG_KALLSYMS], [
AC_MSG_CHECKING([whether CONFIG_KALLSYMS is defined])
SPL_LINUX_TRY_COMPILE([
#if !defined(CONFIG_KALLSYMS)
#error CONFIG_KALLSYMS not defined
#endif
],[ ],[
AC_MSG_RESULT([yes])
],[
AC_MSG_RESULT([no])
AC_MSG_ERROR([
*** This kernel does not include the required kallsyms support.
*** Rebuild the kernel with CONFIG_KALLSYMS=y set.])
])
])
dnl #
dnl # zlib inflate compat,
dnl # Verify the kernel has CONFIG_ZLIB_INFLATE support enabled.

View File

@ -5,7 +5,6 @@ KERNEL_H = \
$(top_srcdir)/include/linux/compiler_compat.h \
$(top_srcdir)/include/linux/delay_compat.h \
$(top_srcdir)/include/linux/file_compat.h \
$(top_srcdir)/include/linux/kallsyms_compat.h \
$(top_srcdir)/include/linux/list_compat.h \
$(top_srcdir)/include/linux/math64_compat.h \
$(top_srcdir)/include/linux/mm_compat.h \

View File

@ -1,44 +0,0 @@
/*****************************************************************************\
* Copyright (C) 2007-2010 Lawrence Livermore National Security, LLC.
* Copyright (C) 2007 The Regents of the University of California.
* Produced at Lawrence Livermore National Laboratory (cf, DISCLAIMER).
* Written by Brian Behlendorf <behlendorf1@llnl.gov>.
* UCRL-CODE-235197
*
* This file is part of the SPL, Solaris Porting Layer.
* For details, see <http://zfsonlinux.org/>.
*
* The SPL is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*
* The SPL is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* for more details.
*
* You should have received a copy of the GNU General Public License along
* with the SPL. If not, see <http://www.gnu.org/licenses/>.
\*****************************************************************************/
#ifndef _SPL_KALLSYMS_COMPAT_H
#define _SPL_KALLSYMS_COMPAT_H
#define SYMBOL_POISON ((void*)0xabcddcba)
#ifdef HAVE_KALLSYMS_LOOKUP_NAME
#include <linux/kallsyms.h>
#define spl_kallsyms_lookup_name(name) kallsyms_lookup_name(name)
#else
extern wait_queue_head_t spl_kallsyms_lookup_name_waitq;
typedef unsigned long (*kallsyms_lookup_name_t)(const char *);
extern kallsyms_lookup_name_t spl_kallsyms_lookup_name_fn;
#define spl_kallsyms_lookup_name(name) spl_kallsyms_lookup_name_fn(name)
#endif /* HAVE_KALLSYMS_LOOKUP_NAME */
#endif /* _SPL_KALLSYMS_COMPAT_H */

View File

@ -31,7 +31,6 @@
#include <linux/file_compat.h>
#include <linux/list_compat.h>
#include <linux/bitops_compat.h>
#include <linux/kallsyms_compat.h>
#include <linux/module_compat.h>
#include <linux/sysctl_compat.h>
#include <linux/proc_compat.h>

View File

@ -59,11 +59,6 @@ MODULE_PARM_DESC(spl_hostid, "The system hostid.");
proc_t p0 = { 0 };
EXPORT_SYMBOL(p0);
#ifndef HAVE_KALLSYMS_LOOKUP_NAME
DECLARE_WAIT_QUEUE_HEAD(spl_kallsyms_lookup_name_waitq);
kallsyms_lookup_name_t spl_kallsyms_lookup_name_fn = SYMBOL_POISON;
#endif
#if BITS_PER_LONG == 32
/*
* Support 64/64 => 64 division on a 32-bit platform. While the kernel
@ -490,64 +485,6 @@ zone_get_hostid(void *zone)
}
EXPORT_SYMBOL(zone_get_hostid);
/*
* The kallsyms_lookup_name() kernel function is not an exported symbol in
* Linux 2.6.19 through 2.6.32 inclusive.
*
* This function replaces the functionality by performing an upcall to user
* space where /proc/kallsyms is consulted for the requested address.
*
*/
#define GET_KALLSYMS_ADDR_CMD \
"exec 0</dev/null " \
" 1>/proc/sys/kernel/spl/kallsyms_lookup_name " \
" 2>/dev/null; " \
"awk '{ if ( $3 == \"kallsyms_lookup_name\" ) { print $1 } }' " \
" /proc/kallsyms "
static int
set_kallsyms_lookup_name(void)
{
#ifndef HAVE_KALLSYMS_LOOKUP_NAME
char *argv[] = { "/bin/sh",
"-c",
GET_KALLSYMS_ADDR_CMD,
NULL };
char *envp[] = { "HOME=/",
"TERM=linux",
"PATH=/sbin:/usr/sbin:/bin:/usr/bin",
NULL };
int rc;
rc = call_usermodehelper(argv[0], argv, envp, UMH_WAIT_PROC);
/*
* Due to I/O buffering the helper may return successfully before
* the proc handler has a chance to execute. To catch this case
* wait up to 1 second to verify spl_kallsyms_lookup_name_fn was
* updated to a non SYMBOL_POISON value.
*/
if (rc == 0) {
rc = wait_event_timeout(spl_kallsyms_lookup_name_waitq,
spl_kallsyms_lookup_name_fn != SYMBOL_POISON, HZ);
if (rc == 0)
rc = -ETIMEDOUT;
else if (spl_kallsyms_lookup_name_fn == SYMBOL_POISON)
rc = -EFAULT;
else
rc = 0;
}
if (rc)
printk("SPL: Failed user helper '%s %s %s', rc = %d\n",
argv[0], argv[1], argv[2], rc);
return (rc);
#else
return (0);
#endif /* HAVE_KALLSYMS_LOOKUP_NAME */
}
static int
__init spl_init(void)
{
@ -583,14 +520,10 @@ __init spl_init(void)
if ((rc = spl_zlib_init()))
SGOTO(out9, rc);
if ((rc = set_kallsyms_lookup_name()))
SGOTO(out10, rc = -EADDRNOTAVAIL);
printk(KERN_NOTICE "SPL: Loaded module v%s-%s%s\n", SPL_META_VERSION,
SPL_META_RELEASE, SPL_DEBUG_STR);
SRETURN(rc);
out10:
spl_zlib_fini();
out9:
spl_tsd_fini();
out8:

View File

@ -409,51 +409,6 @@ SPL_PROC_HANDLER(proc_dohostid)
SRETURN(rc);
}
#ifndef HAVE_KALLSYMS_LOOKUP_NAME
SPL_PROC_HANDLER(proc_dokallsyms_lookup_name)
{
int len, rc = 0;
char *end, str[32];
SENTRY;
if (write) {
/* This may only be set once at module load time */
if (spl_kallsyms_lookup_name_fn != SYMBOL_POISON)
SRETURN(-EEXIST);
/* We can't use spl_proc_doulongvec_minmax() in the write
* case here because the address while a hex value has no
* leading 0x which confuses the helper function. */
rc = proc_copyin_string(str, sizeof(str), buffer, *lenp);
if (rc < 0)
SRETURN(rc);
spl_kallsyms_lookup_name_fn =
(kallsyms_lookup_name_t)simple_strtoul(str, &end, 16);
wake_up(&spl_kallsyms_lookup_name_waitq);
if (str == end)
SRETURN(-EINVAL);
*ppos += *lenp;
} else {
len = snprintf(str, sizeof(str), "%lx",
(unsigned long)spl_kallsyms_lookup_name_fn);
if (*ppos >= len)
rc = 0;
else
rc = proc_copyout_string(buffer,*lenp,str+*ppos,"\n");
if (rc >= 0) {
*lenp = rc;
*ppos += rc;
}
}
SRETURN(rc);
}
#endif /* HAVE_KALLSYMS_LOOKUP_NAME */
#ifdef DEBUG_KMEM
static void
slab_seq_show_headers(struct seq_file *f)
@ -792,15 +747,6 @@ static struct ctl_table spl_table[] = {
.mode = 0644,
.proc_handler = &proc_dohostid,
},
#ifndef HAVE_KALLSYMS_LOOKUP_NAME
{
.procname = "kallsyms_lookup_name",
.data = &spl_kallsyms_lookup_name_fn,
.maxlen = sizeof(unsigned long),
.mode = 0644,
.proc_handler = &proc_dokallsyms_lookup_name,
},
#endif
#ifdef DEBUG_LOG
{
.procname = "debug",