mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-25 02:09:42 +00:00
304 lines
5.8 KiB
C
304 lines
5.8 KiB
C
![]() |
/*
|
||
|
* trace_seq.c
|
||
|
*
|
||
|
* Copyright (C) 2008-2014 Red Hat Inc, Steven Rostedt <srostedt@redhat.com>
|
||
|
*
|
||
|
*/
|
||
|
#include <linux/uaccess.h>
|
||
|
#include <linux/seq_file.h>
|
||
|
#include <linux/trace_seq.h>
|
||
|
|
||
|
int trace_print_seq(struct seq_file *m, struct trace_seq *s)
|
||
|
{
|
||
|
int len = s->len >= PAGE_SIZE ? PAGE_SIZE - 1 : s->len;
|
||
|
int ret;
|
||
|
|
||
|
ret = seq_write(m, s->buffer, len);
|
||
|
|
||
|
/*
|
||
|
* Only reset this buffer if we successfully wrote to the
|
||
|
* seq_file buffer.
|
||
|
*/
|
||
|
if (!ret)
|
||
|
trace_seq_init(s);
|
||
|
|
||
|
return ret;
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* trace_seq_printf - sequence printing of trace information
|
||
|
* @s: trace sequence descriptor
|
||
|
* @fmt: printf format string
|
||
|
*
|
||
|
* It returns 0 if the trace oversizes the buffer's free
|
||
|
* space, 1 otherwise.
|
||
|
*
|
||
|
* The tracer may use either sequence operations or its own
|
||
|
* copy to user routines. To simplify formating of a trace
|
||
|
* trace_seq_printf is used to store strings into a special
|
||
|
* buffer (@s). Then the output may be either used by
|
||
|
* the sequencer or pulled into another buffer.
|
||
|
*/
|
||
|
int
|
||
|
trace_seq_printf(struct trace_seq *s, const char *fmt, ...)
|
||
|
{
|
||
|
int len = (PAGE_SIZE - 1) - s->len;
|
||
|
va_list ap;
|
||
|
int ret;
|
||
|
|
||
|
if (s->full || !len)
|
||
|
return 0;
|
||
|
|
||
|
va_start(ap, fmt);
|
||
|
ret = vsnprintf(s->buffer + s->len, len, fmt, ap);
|
||
|
va_end(ap);
|
||
|
|
||
|
/* If we can't write it all, don't bother writing anything */
|
||
|
if (ret >= len) {
|
||
|
s->full = 1;
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
s->len += ret;
|
||
|
|
||
|
return 1;
|
||
|
}
|
||
|
EXPORT_SYMBOL_GPL(trace_seq_printf);
|
||
|
|
||
|
/**
|
||
|
* trace_seq_bitmask - put a list of longs as a bitmask print output
|
||
|
* @s: trace sequence descriptor
|
||
|
* @maskp: points to an array of unsigned longs that represent a bitmask
|
||
|
* @nmaskbits: The number of bits that are valid in @maskp
|
||
|
*
|
||
|
* It returns 0 if the trace oversizes the buffer's free
|
||
|
* space, 1 otherwise.
|
||
|
*
|
||
|
* Writes a ASCII representation of a bitmask string into @s.
|
||
|
*/
|
||
|
int
|
||
|
trace_seq_bitmask(struct trace_seq *s, const unsigned long *maskp,
|
||
|
int nmaskbits)
|
||
|
{
|
||
|
int len = (PAGE_SIZE - 1) - s->len;
|
||
|
int ret;
|
||
|
|
||
|
if (s->full || !len)
|
||
|
return 0;
|
||
|
|
||
|
ret = bitmap_scnprintf(s->buffer, len, maskp, nmaskbits);
|
||
|
s->len += ret;
|
||
|
|
||
|
return 1;
|
||
|
}
|
||
|
EXPORT_SYMBOL_GPL(trace_seq_bitmask);
|
||
|
|
||
|
/**
|
||
|
* trace_seq_vprintf - sequence printing of trace information
|
||
|
* @s: trace sequence descriptor
|
||
|
* @fmt: printf format string
|
||
|
*
|
||
|
* The tracer may use either sequence operations or its own
|
||
|
* copy to user routines. To simplify formating of a trace
|
||
|
* trace_seq_printf is used to store strings into a special
|
||
|
* buffer (@s). Then the output may be either used by
|
||
|
* the sequencer or pulled into another buffer.
|
||
|
*/
|
||
|
int
|
||
|
trace_seq_vprintf(struct trace_seq *s, const char *fmt, va_list args)
|
||
|
{
|
||
|
int len = (PAGE_SIZE - 1) - s->len;
|
||
|
int ret;
|
||
|
|
||
|
if (s->full || !len)
|
||
|
return 0;
|
||
|
|
||
|
ret = vsnprintf(s->buffer + s->len, len, fmt, args);
|
||
|
|
||
|
/* If we can't write it all, don't bother writing anything */
|
||
|
if (ret >= len) {
|
||
|
s->full = 1;
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
s->len += ret;
|
||
|
|
||
|
return len;
|
||
|
}
|
||
|
EXPORT_SYMBOL_GPL(trace_seq_vprintf);
|
||
|
|
||
|
int trace_seq_bprintf(struct trace_seq *s, const char *fmt, const u32 *binary)
|
||
|
{
|
||
|
int len = (PAGE_SIZE - 1) - s->len;
|
||
|
int ret;
|
||
|
|
||
|
if (s->full || !len)
|
||
|
return 0;
|
||
|
|
||
|
ret = bstr_printf(s->buffer + s->len, len, fmt, binary);
|
||
|
|
||
|
/* If we can't write it all, don't bother writing anything */
|
||
|
if (ret >= len) {
|
||
|
s->full = 1;
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
s->len += ret;
|
||
|
|
||
|
return len;
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* trace_seq_puts - trace sequence printing of simple string
|
||
|
* @s: trace sequence descriptor
|
||
|
* @str: simple string to record
|
||
|
*
|
||
|
* The tracer may use either the sequence operations or its own
|
||
|
* copy to user routines. This function records a simple string
|
||
|
* into a special buffer (@s) for later retrieval by a sequencer
|
||
|
* or other mechanism.
|
||
|
*/
|
||
|
int trace_seq_puts(struct trace_seq *s, const char *str)
|
||
|
{
|
||
|
int len = strlen(str);
|
||
|
|
||
|
if (s->full)
|
||
|
return 0;
|
||
|
|
||
|
if (len > ((PAGE_SIZE - 1) - s->len)) {
|
||
|
s->full = 1;
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
memcpy(s->buffer + s->len, str, len);
|
||
|
s->len += len;
|
||
|
|
||
|
return len;
|
||
|
}
|
||
|
|
||
|
int trace_seq_putc(struct trace_seq *s, unsigned char c)
|
||
|
{
|
||
|
if (s->full)
|
||
|
return 0;
|
||
|
|
||
|
if (s->len >= (PAGE_SIZE - 1)) {
|
||
|
s->full = 1;
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
s->buffer[s->len++] = c;
|
||
|
|
||
|
return 1;
|
||
|
}
|
||
|
EXPORT_SYMBOL(trace_seq_putc);
|
||
|
|
||
|
int trace_seq_putmem(struct trace_seq *s, const void *mem, size_t len)
|
||
|
{
|
||
|
if (s->full)
|
||
|
return 0;
|
||
|
|
||
|
if (len > ((PAGE_SIZE - 1) - s->len)) {
|
||
|
s->full = 1;
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
memcpy(s->buffer + s->len, mem, len);
|
||
|
s->len += len;
|
||
|
|
||
|
return len;
|
||
|
}
|
||
|
|
||
|
#define HEX_CHARS (MAX_MEMHEX_BYTES*2 + 1)
|
||
|
|
||
|
int trace_seq_putmem_hex(struct trace_seq *s, const void *mem, size_t len)
|
||
|
{
|
||
|
unsigned char hex[HEX_CHARS];
|
||
|
const unsigned char *data = mem;
|
||
|
int i, j;
|
||
|
|
||
|
if (s->full)
|
||
|
return 0;
|
||
|
|
||
|
#ifdef __BIG_ENDIAN
|
||
|
for (i = 0, j = 0; i < len; i++) {
|
||
|
#else
|
||
|
for (i = len-1, j = 0; i >= 0; i--) {
|
||
|
#endif
|
||
|
hex[j++] = hex_asc_hi(data[i]);
|
||
|
hex[j++] = hex_asc_lo(data[i]);
|
||
|
}
|
||
|
hex[j++] = ' ';
|
||
|
|
||
|
return trace_seq_putmem(s, hex, j);
|
||
|
}
|
||
|
|
||
|
void *trace_seq_reserve(struct trace_seq *s, size_t len)
|
||
|
{
|
||
|
void *ret;
|
||
|
|
||
|
if (s->full)
|
||
|
return NULL;
|
||
|
|
||
|
if (len > ((PAGE_SIZE - 1) - s->len)) {
|
||
|
s->full = 1;
|
||
|
return NULL;
|
||
|
}
|
||
|
|
||
|
ret = s->buffer + s->len;
|
||
|
s->len += len;
|
||
|
|
||
|
return ret;
|
||
|
}
|
||
|
|
||
|
int trace_seq_path(struct trace_seq *s, const struct path *path)
|
||
|
{
|
||
|
unsigned char *p;
|
||
|
|
||
|
if (s->full)
|
||
|
return 0;
|
||
|
|
||
|
if (s->len >= (PAGE_SIZE - 1)) {
|
||
|
s->full = 1;
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
p = d_path(path, s->buffer + s->len, PAGE_SIZE - s->len);
|
||
|
if (!IS_ERR(p)) {
|
||
|
p = mangle_path(s->buffer + s->len, p, "\n");
|
||
|
if (p) {
|
||
|
s->len = p - s->buffer;
|
||
|
return 1;
|
||
|
}
|
||
|
} else {
|
||
|
s->buffer[s->len++] = '?';
|
||
|
return 1;
|
||
|
}
|
||
|
|
||
|
s->full = 1;
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt)
|
||
|
{
|
||
|
int len;
|
||
|
int ret;
|
||
|
|
||
|
if (!cnt)
|
||
|
return 0;
|
||
|
|
||
|
if (s->len <= s->readpos)
|
||
|
return -EBUSY;
|
||
|
|
||
|
len = s->len - s->readpos;
|
||
|
if (cnt > len)
|
||
|
cnt = len;
|
||
|
ret = copy_to_user(ubuf, s->buffer + s->readpos, cnt);
|
||
|
if (ret == cnt)
|
||
|
return -EFAULT;
|
||
|
|
||
|
cnt -= ret;
|
||
|
|
||
|
s->readpos += cnt;
|
||
|
return cnt;
|
||
|
}
|