tracing: Extract out common code for kprobes/uprobes trace events
Move parts of trace_kprobe.c that can be shared with upcoming trace_uprobe.c. Common code to kernel/trace/trace_probe.h and kernel/trace/trace_probe.c. There are no functional changes. Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Jim Keniston <jkenisto@linux.vnet.ibm.com> Cc: Linux-mm <linux-mm@kvack.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Christoph Hellwig <hch@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Anton Arapov <anton@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20120409091144.8343.76218.sendpatchset@srdronam.in.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Srikar Dronamraju
committed by
Ingo Molnar
Ingo Molnar
parent
3a6b76661d
commit
8ab83f5647
833
kernel/trace/trace_probe.c
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833
kernel/trace/trace_probe.c
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@@ -0,0 +1,833 @@
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/*
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* Common code for probe-based Dynamic events.
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*
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* This code was copied from kernel/trace/trace_kprobe.c written by
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* Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
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*
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* Updates to make this generic:
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* Copyright (C) IBM Corporation, 2010-2011
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* Author: Srikar Dronamraju
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*/
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#include "trace_probe.h"
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const char *reserved_field_names[] = {
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"common_type",
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"common_flags",
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"common_preempt_count",
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"common_pid",
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"common_tgid",
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FIELD_STRING_IP,
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FIELD_STRING_RETIP,
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FIELD_STRING_FUNC,
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};
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/* Printing function type */
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#define PRINT_TYPE_FUNC_NAME(type) print_type_##type
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#define PRINT_TYPE_FMT_NAME(type) print_type_format_##type
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/* Printing in basic type function template */
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#define DEFINE_BASIC_PRINT_TYPE_FUNC(type, fmt, cast) \
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static __kprobes int PRINT_TYPE_FUNC_NAME(type)(struct trace_seq *s, \
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const char *name, \
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void *data, void *ent)\
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{ \
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return trace_seq_printf(s, " %s=" fmt, name, (cast)*(type *)data);\
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} \
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static const char PRINT_TYPE_FMT_NAME(type)[] = fmt;
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DEFINE_BASIC_PRINT_TYPE_FUNC(u8, "%x", unsigned int)
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DEFINE_BASIC_PRINT_TYPE_FUNC(u16, "%x", unsigned int)
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DEFINE_BASIC_PRINT_TYPE_FUNC(u32, "%lx", unsigned long)
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DEFINE_BASIC_PRINT_TYPE_FUNC(u64, "%llx", unsigned long long)
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DEFINE_BASIC_PRINT_TYPE_FUNC(s8, "%d", int)
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DEFINE_BASIC_PRINT_TYPE_FUNC(s16, "%d", int)
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DEFINE_BASIC_PRINT_TYPE_FUNC(s32, "%ld", long)
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DEFINE_BASIC_PRINT_TYPE_FUNC(s64, "%lld", long long)
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static inline void *get_rloc_data(u32 *dl)
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{
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return (u8 *)dl + get_rloc_offs(*dl);
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}
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/* For data_loc conversion */
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static inline void *get_loc_data(u32 *dl, void *ent)
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{
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return (u8 *)ent + get_rloc_offs(*dl);
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}
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/* For defining macros, define string/string_size types */
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typedef u32 string;
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typedef u32 string_size;
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/* Print type function for string type */
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static __kprobes int PRINT_TYPE_FUNC_NAME(string)(struct trace_seq *s,
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const char *name,
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void *data, void *ent)
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{
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int len = *(u32 *)data >> 16;
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if (!len)
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return trace_seq_printf(s, " %s=(fault)", name);
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else
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return trace_seq_printf(s, " %s=\"%s\"", name,
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(const char *)get_loc_data(data, ent));
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}
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static const char PRINT_TYPE_FMT_NAME(string)[] = "\\\"%s\\\"";
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#define FETCH_FUNC_NAME(method, type) fetch_##method##_##type
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/*
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* Define macro for basic types - we don't need to define s* types, because
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* we have to care only about bitwidth at recording time.
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*/
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#define DEFINE_BASIC_FETCH_FUNCS(method) \
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DEFINE_FETCH_##method(u8) \
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DEFINE_FETCH_##method(u16) \
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DEFINE_FETCH_##method(u32) \
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DEFINE_FETCH_##method(u64)
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#define CHECK_FETCH_FUNCS(method, fn) \
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(((FETCH_FUNC_NAME(method, u8) == fn) || \
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(FETCH_FUNC_NAME(method, u16) == fn) || \
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(FETCH_FUNC_NAME(method, u32) == fn) || \
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(FETCH_FUNC_NAME(method, u64) == fn) || \
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(FETCH_FUNC_NAME(method, string) == fn) || \
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(FETCH_FUNC_NAME(method, string_size) == fn)) \
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&& (fn != NULL))
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/* Data fetch function templates */
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#define DEFINE_FETCH_reg(type) \
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static __kprobes void FETCH_FUNC_NAME(reg, type)(struct pt_regs *regs, \
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void *offset, void *dest) \
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{ \
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*(type *)dest = (type)regs_get_register(regs, \
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(unsigned int)((unsigned long)offset)); \
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}
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DEFINE_BASIC_FETCH_FUNCS(reg)
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/* No string on the register */
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#define fetch_reg_string NULL
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#define fetch_reg_string_size NULL
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#define DEFINE_FETCH_stack(type) \
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static __kprobes void FETCH_FUNC_NAME(stack, type)(struct pt_regs *regs,\
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void *offset, void *dest) \
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{ \
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*(type *)dest = (type)regs_get_kernel_stack_nth(regs, \
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(unsigned int)((unsigned long)offset)); \
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}
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DEFINE_BASIC_FETCH_FUNCS(stack)
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/* No string on the stack entry */
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#define fetch_stack_string NULL
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#define fetch_stack_string_size NULL
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#define DEFINE_FETCH_retval(type) \
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static __kprobes void FETCH_FUNC_NAME(retval, type)(struct pt_regs *regs,\
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void *dummy, void *dest) \
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{ \
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*(type *)dest = (type)regs_return_value(regs); \
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}
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DEFINE_BASIC_FETCH_FUNCS(retval)
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/* No string on the retval */
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#define fetch_retval_string NULL
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#define fetch_retval_string_size NULL
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#define DEFINE_FETCH_memory(type) \
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static __kprobes void FETCH_FUNC_NAME(memory, type)(struct pt_regs *regs,\
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void *addr, void *dest) \
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{ \
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type retval; \
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if (probe_kernel_address(addr, retval)) \
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*(type *)dest = 0; \
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else \
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*(type *)dest = retval; \
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}
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DEFINE_BASIC_FETCH_FUNCS(memory)
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/*
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* Fetch a null-terminated string. Caller MUST set *(u32 *)dest with max
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* length and relative data location.
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*/
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static __kprobes void FETCH_FUNC_NAME(memory, string)(struct pt_regs *regs,
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void *addr, void *dest)
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{
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long ret;
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int maxlen = get_rloc_len(*(u32 *)dest);
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u8 *dst = get_rloc_data(dest);
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u8 *src = addr;
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mm_segment_t old_fs = get_fs();
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if (!maxlen)
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return;
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/*
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* Try to get string again, since the string can be changed while
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* probing.
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*/
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set_fs(KERNEL_DS);
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pagefault_disable();
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do
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ret = __copy_from_user_inatomic(dst++, src++, 1);
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while (dst[-1] && ret == 0 && src - (u8 *)addr < maxlen);
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dst[-1] = '\0';
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pagefault_enable();
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set_fs(old_fs);
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if (ret < 0) { /* Failed to fetch string */
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((u8 *)get_rloc_data(dest))[0] = '\0';
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*(u32 *)dest = make_data_rloc(0, get_rloc_offs(*(u32 *)dest));
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} else {
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*(u32 *)dest = make_data_rloc(src - (u8 *)addr,
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get_rloc_offs(*(u32 *)dest));
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}
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}
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/* Return the length of string -- including null terminal byte */
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static __kprobes void FETCH_FUNC_NAME(memory, string_size)(struct pt_regs *regs,
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void *addr, void *dest)
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{
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mm_segment_t old_fs;
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int ret, len = 0;
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u8 c;
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old_fs = get_fs();
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set_fs(KERNEL_DS);
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pagefault_disable();
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do {
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ret = __copy_from_user_inatomic(&c, (u8 *)addr + len, 1);
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len++;
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} while (c && ret == 0 && len < MAX_STRING_SIZE);
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pagefault_enable();
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set_fs(old_fs);
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if (ret < 0) /* Failed to check the length */
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*(u32 *)dest = 0;
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else
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*(u32 *)dest = len;
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}
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/* Memory fetching by symbol */
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struct symbol_cache {
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char *symbol;
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long offset;
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unsigned long addr;
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};
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static unsigned long update_symbol_cache(struct symbol_cache *sc)
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{
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sc->addr = (unsigned long)kallsyms_lookup_name(sc->symbol);
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if (sc->addr)
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sc->addr += sc->offset;
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return sc->addr;
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}
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static void free_symbol_cache(struct symbol_cache *sc)
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{
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kfree(sc->symbol);
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kfree(sc);
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}
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static struct symbol_cache *alloc_symbol_cache(const char *sym, long offset)
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{
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struct symbol_cache *sc;
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if (!sym || strlen(sym) == 0)
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return NULL;
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sc = kzalloc(sizeof(struct symbol_cache), GFP_KERNEL);
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if (!sc)
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return NULL;
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sc->symbol = kstrdup(sym, GFP_KERNEL);
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if (!sc->symbol) {
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kfree(sc);
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return NULL;
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}
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sc->offset = offset;
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update_symbol_cache(sc);
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return sc;
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}
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#define DEFINE_FETCH_symbol(type) \
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static __kprobes void FETCH_FUNC_NAME(symbol, type)(struct pt_regs *regs,\
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void *data, void *dest) \
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{ \
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struct symbol_cache *sc = data; \
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if (sc->addr) \
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fetch_memory_##type(regs, (void *)sc->addr, dest); \
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else \
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*(type *)dest = 0; \
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}
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DEFINE_BASIC_FETCH_FUNCS(symbol)
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DEFINE_FETCH_symbol(string)
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DEFINE_FETCH_symbol(string_size)
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/* Dereference memory access function */
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struct deref_fetch_param {
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struct fetch_param orig;
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long offset;
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};
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#define DEFINE_FETCH_deref(type) \
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static __kprobes void FETCH_FUNC_NAME(deref, type)(struct pt_regs *regs,\
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void *data, void *dest) \
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{ \
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struct deref_fetch_param *dprm = data; \
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unsigned long addr; \
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call_fetch(&dprm->orig, regs, &addr); \
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if (addr) { \
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addr += dprm->offset; \
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fetch_memory_##type(regs, (void *)addr, dest); \
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} else \
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*(type *)dest = 0; \
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}
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DEFINE_BASIC_FETCH_FUNCS(deref)
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DEFINE_FETCH_deref(string)
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DEFINE_FETCH_deref(string_size)
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static __kprobes void update_deref_fetch_param(struct deref_fetch_param *data)
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{
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if (CHECK_FETCH_FUNCS(deref, data->orig.fn))
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update_deref_fetch_param(data->orig.data);
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else if (CHECK_FETCH_FUNCS(symbol, data->orig.fn))
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update_symbol_cache(data->orig.data);
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}
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static __kprobes void free_deref_fetch_param(struct deref_fetch_param *data)
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{
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if (CHECK_FETCH_FUNCS(deref, data->orig.fn))
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free_deref_fetch_param(data->orig.data);
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else if (CHECK_FETCH_FUNCS(symbol, data->orig.fn))
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free_symbol_cache(data->orig.data);
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kfree(data);
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}
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/* Bitfield fetch function */
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struct bitfield_fetch_param {
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struct fetch_param orig;
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unsigned char hi_shift;
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unsigned char low_shift;
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};
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#define DEFINE_FETCH_bitfield(type) \
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static __kprobes void FETCH_FUNC_NAME(bitfield, type)(struct pt_regs *regs,\
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void *data, void *dest) \
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{ \
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struct bitfield_fetch_param *bprm = data; \
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type buf = 0; \
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call_fetch(&bprm->orig, regs, &buf); \
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if (buf) { \
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buf <<= bprm->hi_shift; \
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buf >>= bprm->low_shift; \
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} \
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*(type *)dest = buf; \
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}
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DEFINE_BASIC_FETCH_FUNCS(bitfield)
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#define fetch_bitfield_string NULL
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#define fetch_bitfield_string_size NULL
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static __kprobes void
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update_bitfield_fetch_param(struct bitfield_fetch_param *data)
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{
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/*
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* Don't check the bitfield itself, because this must be the
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* last fetch function.
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*/
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if (CHECK_FETCH_FUNCS(deref, data->orig.fn))
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update_deref_fetch_param(data->orig.data);
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else if (CHECK_FETCH_FUNCS(symbol, data->orig.fn))
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update_symbol_cache(data->orig.data);
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}
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static __kprobes void
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free_bitfield_fetch_param(struct bitfield_fetch_param *data)
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{
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/*
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* Don't check the bitfield itself, because this must be the
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* last fetch function.
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*/
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if (CHECK_FETCH_FUNCS(deref, data->orig.fn))
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free_deref_fetch_param(data->orig.data);
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else if (CHECK_FETCH_FUNCS(symbol, data->orig.fn))
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free_symbol_cache(data->orig.data);
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kfree(data);
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}
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/* Default (unsigned long) fetch type */
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#define __DEFAULT_FETCH_TYPE(t) u##t
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#define _DEFAULT_FETCH_TYPE(t) __DEFAULT_FETCH_TYPE(t)
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#define DEFAULT_FETCH_TYPE _DEFAULT_FETCH_TYPE(BITS_PER_LONG)
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#define DEFAULT_FETCH_TYPE_STR __stringify(DEFAULT_FETCH_TYPE)
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#define ASSIGN_FETCH_FUNC(method, type) \
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[FETCH_MTD_##method] = FETCH_FUNC_NAME(method, type)
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#define __ASSIGN_FETCH_TYPE(_name, ptype, ftype, _size, sign, _fmttype) \
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{.name = _name, \
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.size = _size, \
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.is_signed = sign, \
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.print = PRINT_TYPE_FUNC_NAME(ptype), \
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.fmt = PRINT_TYPE_FMT_NAME(ptype), \
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.fmttype = _fmttype, \
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.fetch = { \
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ASSIGN_FETCH_FUNC(reg, ftype), \
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ASSIGN_FETCH_FUNC(stack, ftype), \
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ASSIGN_FETCH_FUNC(retval, ftype), \
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ASSIGN_FETCH_FUNC(memory, ftype), \
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ASSIGN_FETCH_FUNC(symbol, ftype), \
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ASSIGN_FETCH_FUNC(deref, ftype), \
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ASSIGN_FETCH_FUNC(bitfield, ftype), \
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} \
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}
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#define ASSIGN_FETCH_TYPE(ptype, ftype, sign) \
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__ASSIGN_FETCH_TYPE(#ptype, ptype, ftype, sizeof(ftype), sign, #ptype)
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#define FETCH_TYPE_STRING 0
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#define FETCH_TYPE_STRSIZE 1
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/* Fetch type information table */
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static const struct fetch_type fetch_type_table[] = {
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/* Special types */
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[FETCH_TYPE_STRING] = __ASSIGN_FETCH_TYPE("string", string, string,
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sizeof(u32), 1, "__data_loc char[]"),
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[FETCH_TYPE_STRSIZE] = __ASSIGN_FETCH_TYPE("string_size", u32,
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string_size, sizeof(u32), 0, "u32"),
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/* Basic types */
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ASSIGN_FETCH_TYPE(u8, u8, 0),
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ASSIGN_FETCH_TYPE(u16, u16, 0),
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ASSIGN_FETCH_TYPE(u32, u32, 0),
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ASSIGN_FETCH_TYPE(u64, u64, 0),
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ASSIGN_FETCH_TYPE(s8, u8, 1),
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ASSIGN_FETCH_TYPE(s16, u16, 1),
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ASSIGN_FETCH_TYPE(s32, u32, 1),
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ASSIGN_FETCH_TYPE(s64, u64, 1),
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};
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static const struct fetch_type *find_fetch_type(const char *type)
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{
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int i;
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if (!type)
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type = DEFAULT_FETCH_TYPE_STR;
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|
||||
/* Special case: bitfield */
|
||||
if (*type == 'b') {
|
||||
unsigned long bs;
|
||||
|
||||
type = strchr(type, '/');
|
||||
if (!type)
|
||||
goto fail;
|
||||
|
||||
type++;
|
||||
if (strict_strtoul(type, 0, &bs))
|
||||
goto fail;
|
||||
|
||||
switch (bs) {
|
||||
case 8:
|
||||
return find_fetch_type("u8");
|
||||
case 16:
|
||||
return find_fetch_type("u16");
|
||||
case 32:
|
||||
return find_fetch_type("u32");
|
||||
case 64:
|
||||
return find_fetch_type("u64");
|
||||
default:
|
||||
goto fail;
|
||||
}
|
||||
}
|
||||
|
||||
for (i = 0; i < ARRAY_SIZE(fetch_type_table); i++)
|
||||
if (strcmp(type, fetch_type_table[i].name) == 0)
|
||||
return &fetch_type_table[i];
|
||||
|
||||
fail:
|
||||
return NULL;
|
||||
}
|
||||
|
||||
/* Special function : only accept unsigned long */
|
||||
static __kprobes void fetch_stack_address(struct pt_regs *regs,
|
||||
void *dummy, void *dest)
|
||||
{
|
||||
*(unsigned long *)dest = kernel_stack_pointer(regs);
|
||||
}
|
||||
|
||||
static fetch_func_t get_fetch_size_function(const struct fetch_type *type,
|
||||
fetch_func_t orig_fn)
|
||||
{
|
||||
int i;
|
||||
|
||||
if (type != &fetch_type_table[FETCH_TYPE_STRING])
|
||||
return NULL; /* Only string type needs size function */
|
||||
|
||||
for (i = 0; i < FETCH_MTD_END; i++)
|
||||
if (type->fetch[i] == orig_fn)
|
||||
return fetch_type_table[FETCH_TYPE_STRSIZE].fetch[i];
|
||||
|
||||
WARN_ON(1); /* This should not happen */
|
||||
|
||||
return NULL;
|
||||
}
|
||||
|
||||
/* Split symbol and offset. */
|
||||
int traceprobe_split_symbol_offset(char *symbol, unsigned long *offset)
|
||||
{
|
||||
char *tmp;
|
||||
int ret;
|
||||
|
||||
if (!offset)
|
||||
return -EINVAL;
|
||||
|
||||
tmp = strchr(symbol, '+');
|
||||
if (tmp) {
|
||||
/* skip sign because strict_strtol doesn't accept '+' */
|
||||
ret = strict_strtoul(tmp + 1, 0, offset);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
*tmp = '\0';
|
||||
} else
|
||||
*offset = 0;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
#define PARAM_MAX_STACK (THREAD_SIZE / sizeof(unsigned long))
|
||||
|
||||
static int parse_probe_vars(char *arg, const struct fetch_type *t,
|
||||
struct fetch_param *f, bool is_return)
|
||||
{
|
||||
int ret = 0;
|
||||
unsigned long param;
|
||||
|
||||
if (strcmp(arg, "retval") == 0) {
|
||||
if (is_return)
|
||||
f->fn = t->fetch[FETCH_MTD_retval];
|
||||
else
|
||||
ret = -EINVAL;
|
||||
} else if (strncmp(arg, "stack", 5) == 0) {
|
||||
if (arg[5] == '\0') {
|
||||
if (strcmp(t->name, DEFAULT_FETCH_TYPE_STR) == 0)
|
||||
f->fn = fetch_stack_address;
|
||||
else
|
||||
ret = -EINVAL;
|
||||
} else if (isdigit(arg[5])) {
|
||||
ret = strict_strtoul(arg + 5, 10, ¶m);
|
||||
if (ret || param > PARAM_MAX_STACK)
|
||||
ret = -EINVAL;
|
||||
else {
|
||||
f->fn = t->fetch[FETCH_MTD_stack];
|
||||
f->data = (void *)param;
|
||||
}
|
||||
} else
|
||||
ret = -EINVAL;
|
||||
} else
|
||||
ret = -EINVAL;
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
/* Recursive argument parser */
|
||||
static int parse_probe_arg(char *arg, const struct fetch_type *t,
|
||||
struct fetch_param *f, bool is_return)
|
||||
{
|
||||
unsigned long param;
|
||||
long offset;
|
||||
char *tmp;
|
||||
int ret;
|
||||
|
||||
ret = 0;
|
||||
switch (arg[0]) {
|
||||
case '$':
|
||||
ret = parse_probe_vars(arg + 1, t, f, is_return);
|
||||
break;
|
||||
|
||||
case '%': /* named register */
|
||||
ret = regs_query_register_offset(arg + 1);
|
||||
if (ret >= 0) {
|
||||
f->fn = t->fetch[FETCH_MTD_reg];
|
||||
f->data = (void *)(unsigned long)ret;
|
||||
ret = 0;
|
||||
}
|
||||
break;
|
||||
|
||||
case '@': /* memory or symbol */
|
||||
if (isdigit(arg[1])) {
|
||||
ret = strict_strtoul(arg + 1, 0, ¶m);
|
||||
if (ret)
|
||||
break;
|
||||
|
||||
f->fn = t->fetch[FETCH_MTD_memory];
|
||||
f->data = (void *)param;
|
||||
} else {
|
||||
ret = traceprobe_split_symbol_offset(arg + 1, &offset);
|
||||
if (ret)
|
||||
break;
|
||||
|
||||
f->data = alloc_symbol_cache(arg + 1, offset);
|
||||
if (f->data)
|
||||
f->fn = t->fetch[FETCH_MTD_symbol];
|
||||
}
|
||||
break;
|
||||
|
||||
case '+': /* deref memory */
|
||||
arg++; /* Skip '+', because strict_strtol() rejects it. */
|
||||
case '-':
|
||||
tmp = strchr(arg, '(');
|
||||
if (!tmp)
|
||||
break;
|
||||
|
||||
*tmp = '\0';
|
||||
ret = strict_strtol(arg, 0, &offset);
|
||||
|
||||
if (ret)
|
||||
break;
|
||||
|
||||
arg = tmp + 1;
|
||||
tmp = strrchr(arg, ')');
|
||||
|
||||
if (tmp) {
|
||||
struct deref_fetch_param *dprm;
|
||||
const struct fetch_type *t2;
|
||||
|
||||
t2 = find_fetch_type(NULL);
|
||||
*tmp = '\0';
|
||||
dprm = kzalloc(sizeof(struct deref_fetch_param), GFP_KERNEL);
|
||||
|
||||
if (!dprm)
|
||||
return -ENOMEM;
|
||||
|
||||
dprm->offset = offset;
|
||||
ret = parse_probe_arg(arg, t2, &dprm->orig, is_return);
|
||||
if (ret)
|
||||
kfree(dprm);
|
||||
else {
|
||||
f->fn = t->fetch[FETCH_MTD_deref];
|
||||
f->data = (void *)dprm;
|
||||
}
|
||||
}
|
||||
break;
|
||||
}
|
||||
if (!ret && !f->fn) { /* Parsed, but do not find fetch method */
|
||||
pr_info("%s type has no corresponding fetch method.\n", t->name);
|
||||
ret = -EINVAL;
|
||||
}
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
#define BYTES_TO_BITS(nb) ((BITS_PER_LONG * (nb)) / sizeof(long))
|
||||
|
||||
/* Bitfield type needs to be parsed into a fetch function */
|
||||
static int __parse_bitfield_probe_arg(const char *bf,
|
||||
const struct fetch_type *t,
|
||||
struct fetch_param *f)
|
||||
{
|
||||
struct bitfield_fetch_param *bprm;
|
||||
unsigned long bw, bo;
|
||||
char *tail;
|
||||
|
||||
if (*bf != 'b')
|
||||
return 0;
|
||||
|
||||
bprm = kzalloc(sizeof(*bprm), GFP_KERNEL);
|
||||
if (!bprm)
|
||||
return -ENOMEM;
|
||||
|
||||
bprm->orig = *f;
|
||||
f->fn = t->fetch[FETCH_MTD_bitfield];
|
||||
f->data = (void *)bprm;
|
||||
bw = simple_strtoul(bf + 1, &tail, 0); /* Use simple one */
|
||||
|
||||
if (bw == 0 || *tail != '@')
|
||||
return -EINVAL;
|
||||
|
||||
bf = tail + 1;
|
||||
bo = simple_strtoul(bf, &tail, 0);
|
||||
|
||||
if (tail == bf || *tail != '/')
|
||||
return -EINVAL;
|
||||
|
||||
bprm->hi_shift = BYTES_TO_BITS(t->size) - (bw + bo);
|
||||
bprm->low_shift = bprm->hi_shift + bo;
|
||||
|
||||
return (BYTES_TO_BITS(t->size) < (bw + bo)) ? -EINVAL : 0;
|
||||
}
|
||||
|
||||
/* String length checking wrapper */
|
||||
int traceprobe_parse_probe_arg(char *arg, ssize_t *size,
|
||||
struct probe_arg *parg, bool is_return)
|
||||
{
|
||||
const char *t;
|
||||
int ret;
|
||||
|
||||
if (strlen(arg) > MAX_ARGSTR_LEN) {
|
||||
pr_info("Argument is too long.: %s\n", arg);
|
||||
return -ENOSPC;
|
||||
}
|
||||
parg->comm = kstrdup(arg, GFP_KERNEL);
|
||||
if (!parg->comm) {
|
||||
pr_info("Failed to allocate memory for command '%s'.\n", arg);
|
||||
return -ENOMEM;
|
||||
}
|
||||
t = strchr(parg->comm, ':');
|
||||
if (t) {
|
||||
arg[t - parg->comm] = '\0';
|
||||
t++;
|
||||
}
|
||||
parg->type = find_fetch_type(t);
|
||||
if (!parg->type) {
|
||||
pr_info("Unsupported type: %s\n", t);
|
||||
return -EINVAL;
|
||||
}
|
||||
parg->offset = *size;
|
||||
*size += parg->type->size;
|
||||
ret = parse_probe_arg(arg, parg->type, &parg->fetch, is_return);
|
||||
|
||||
if (ret >= 0 && t != NULL)
|
||||
ret = __parse_bitfield_probe_arg(t, parg->type, &parg->fetch);
|
||||
|
||||
if (ret >= 0) {
|
||||
parg->fetch_size.fn = get_fetch_size_function(parg->type,
|
||||
parg->fetch.fn);
|
||||
parg->fetch_size.data = parg->fetch.data;
|
||||
}
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
/* Return 1 if name is reserved or already used by another argument */
|
||||
int traceprobe_conflict_field_name(const char *name,
|
||||
struct probe_arg *args, int narg)
|
||||
{
|
||||
int i;
|
||||
|
||||
for (i = 0; i < ARRAY_SIZE(reserved_field_names); i++)
|
||||
if (strcmp(reserved_field_names[i], name) == 0)
|
||||
return 1;
|
||||
|
||||
for (i = 0; i < narg; i++)
|
||||
if (strcmp(args[i].name, name) == 0)
|
||||
return 1;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
void traceprobe_update_arg(struct probe_arg *arg)
|
||||
{
|
||||
if (CHECK_FETCH_FUNCS(bitfield, arg->fetch.fn))
|
||||
update_bitfield_fetch_param(arg->fetch.data);
|
||||
else if (CHECK_FETCH_FUNCS(deref, arg->fetch.fn))
|
||||
update_deref_fetch_param(arg->fetch.data);
|
||||
else if (CHECK_FETCH_FUNCS(symbol, arg->fetch.fn))
|
||||
update_symbol_cache(arg->fetch.data);
|
||||
}
|
||||
|
||||
void traceprobe_free_probe_arg(struct probe_arg *arg)
|
||||
{
|
||||
if (CHECK_FETCH_FUNCS(bitfield, arg->fetch.fn))
|
||||
free_bitfield_fetch_param(arg->fetch.data);
|
||||
else if (CHECK_FETCH_FUNCS(deref, arg->fetch.fn))
|
||||
free_deref_fetch_param(arg->fetch.data);
|
||||
else if (CHECK_FETCH_FUNCS(symbol, arg->fetch.fn))
|
||||
free_symbol_cache(arg->fetch.data);
|
||||
|
||||
kfree(arg->name);
|
||||
kfree(arg->comm);
|
||||
}
|
||||
|
||||
int traceprobe_command(const char *buf, int (*createfn)(int, char **))
|
||||
{
|
||||
char **argv;
|
||||
int argc, ret;
|
||||
|
||||
argc = 0;
|
||||
ret = 0;
|
||||
argv = argv_split(GFP_KERNEL, buf, &argc);
|
||||
if (!argv)
|
||||
return -ENOMEM;
|
||||
|
||||
if (argc)
|
||||
ret = createfn(argc, argv);
|
||||
|
||||
argv_free(argv);
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
#define WRITE_BUFSIZE 4096
|
||||
|
||||
ssize_t traceprobe_probes_write(struct file *file, const char __user *buffer,
|
||||
size_t count, loff_t *ppos,
|
||||
int (*createfn)(int, char **))
|
||||
{
|
||||
char *kbuf, *tmp;
|
||||
int ret = 0;
|
||||
size_t done = 0;
|
||||
size_t size;
|
||||
|
||||
kbuf = kmalloc(WRITE_BUFSIZE, GFP_KERNEL);
|
||||
if (!kbuf)
|
||||
return -ENOMEM;
|
||||
|
||||
while (done < count) {
|
||||
size = count - done;
|
||||
|
||||
if (size >= WRITE_BUFSIZE)
|
||||
size = WRITE_BUFSIZE - 1;
|
||||
|
||||
if (copy_from_user(kbuf, buffer + done, size)) {
|
||||
ret = -EFAULT;
|
||||
goto out;
|
||||
}
|
||||
kbuf[size] = '\0';
|
||||
tmp = strchr(kbuf, '\n');
|
||||
|
||||
if (tmp) {
|
||||
*tmp = '\0';
|
||||
size = tmp - kbuf + 1;
|
||||
} else if (done + size < count) {
|
||||
pr_warning("Line length is too long: "
|
||||
"Should be less than %d.", WRITE_BUFSIZE);
|
||||
ret = -EINVAL;
|
||||
goto out;
|
||||
}
|
||||
done += size;
|
||||
/* Remove comments */
|
||||
tmp = strchr(kbuf, '#');
|
||||
|
||||
if (tmp)
|
||||
*tmp = '\0';
|
||||
|
||||
ret = traceprobe_command(kbuf, createfn);
|
||||
if (ret)
|
||||
goto out;
|
||||
}
|
||||
ret = done;
|
||||
|
||||
out:
|
||||
kfree(kbuf);
|
||||
|
||||
return ret;
|
||||
}
|
||||
Reference in New Issue
Block a user