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linux/drivers/gpu/drm/drm_print.c
Matthew Brost 53369581dc drm/printer: Allow NULL data in devcoredump printer
We want to determine the size of the devcoredump before writing it out.
To that end, we will run the devcoredump printer with NULL data to get
the size, alloc data based on the generated offset, then run the
devcorecump again with a valid data pointer to print.  This necessitates
not writing data to the data pointer on the initial pass, when it is
NULL.

v5:
 - Better commit message (Jonathan)
 - Add kerenl doc with examples (Jani)

Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Acked-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Jonathan Cavitt <jonathan.cavitt@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240801154118.2547543-3-matthew.brost@intel.com
2024-08-01 11:00:12 -07:00

379 lines
9.6 KiB
C

/*
* Copyright (C) 2016 Red Hat
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
* OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
* ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
* OTHER DEALINGS IN THE SOFTWARE.
*
* Authors:
* Rob Clark <robdclark@gmail.com>
*/
#include <linux/debugfs.h>
#include <linux/dynamic_debug.h>
#include <linux/io.h>
#include <linux/moduleparam.h>
#include <linux/seq_file.h>
#include <linux/slab.h>
#include <linux/stdarg.h>
#include <drm/drm.h>
#include <drm/drm_drv.h>
#include <drm/drm_print.h>
/*
* __drm_debug: Enable debug output.
* Bitmask of DRM_UT_x. See include/drm/drm_print.h for details.
*/
unsigned long __drm_debug;
EXPORT_SYMBOL(__drm_debug);
MODULE_PARM_DESC(debug, "Enable debug output, where each bit enables a debug category.\n"
"\t\tBit 0 (0x01) will enable CORE messages (drm core code)\n"
"\t\tBit 1 (0x02) will enable DRIVER messages (drm controller code)\n"
"\t\tBit 2 (0x04) will enable KMS messages (modesetting code)\n"
"\t\tBit 3 (0x08) will enable PRIME messages (prime code)\n"
"\t\tBit 4 (0x10) will enable ATOMIC messages (atomic code)\n"
"\t\tBit 5 (0x20) will enable VBL messages (vblank code)\n"
"\t\tBit 7 (0x80) will enable LEASE messages (leasing code)\n"
"\t\tBit 8 (0x100) will enable DP messages (displayport code)");
#if !defined(CONFIG_DRM_USE_DYNAMIC_DEBUG)
module_param_named(debug, __drm_debug, ulong, 0600);
#else
/* classnames must match vals of enum drm_debug_category */
DECLARE_DYNDBG_CLASSMAP(drm_debug_classes, DD_CLASS_TYPE_DISJOINT_BITS, 0,
"DRM_UT_CORE",
"DRM_UT_DRIVER",
"DRM_UT_KMS",
"DRM_UT_PRIME",
"DRM_UT_ATOMIC",
"DRM_UT_VBL",
"DRM_UT_STATE",
"DRM_UT_LEASE",
"DRM_UT_DP",
"DRM_UT_DRMRES");
static struct ddebug_class_param drm_debug_bitmap = {
.bits = &__drm_debug,
.flags = "p",
.map = &drm_debug_classes,
};
module_param_cb(debug, &param_ops_dyndbg_classes, &drm_debug_bitmap, 0600);
#endif
void __drm_puts_coredump(struct drm_printer *p, const char *str)
{
struct drm_print_iterator *iterator = p->arg;
ssize_t len;
if (!iterator->remain)
return;
if (iterator->offset < iterator->start) {
ssize_t copy;
len = strlen(str);
if (iterator->offset + len <= iterator->start) {
iterator->offset += len;
return;
}
copy = len - (iterator->start - iterator->offset);
if (copy > iterator->remain)
copy = iterator->remain;
/* Copy out the bit of the string that we need */
if (iterator->data)
memcpy(iterator->data,
str + (iterator->start - iterator->offset), copy);
iterator->offset = iterator->start + copy;
iterator->remain -= copy;
} else {
ssize_t pos = iterator->offset - iterator->start;
len = min_t(ssize_t, strlen(str), iterator->remain);
if (iterator->data)
memcpy(iterator->data + pos, str, len);
iterator->offset += len;
iterator->remain -= len;
}
}
EXPORT_SYMBOL(__drm_puts_coredump);
void __drm_printfn_coredump(struct drm_printer *p, struct va_format *vaf)
{
struct drm_print_iterator *iterator = p->arg;
size_t len;
char *buf;
if (!iterator->remain)
return;
/* Figure out how big the string will be */
len = snprintf(NULL, 0, "%pV", vaf);
/* This is the easiest path, we've already advanced beyond the offset */
if (iterator->offset + len <= iterator->start) {
iterator->offset += len;
return;
}
/* Then check if we can directly copy into the target buffer */
if ((iterator->offset >= iterator->start) && (len < iterator->remain)) {
ssize_t pos = iterator->offset - iterator->start;
if (iterator->data)
snprintf(((char *) iterator->data) + pos,
iterator->remain, "%pV", vaf);
iterator->offset += len;
iterator->remain -= len;
return;
}
/*
* Finally, hit the slow path and make a temporary string to copy over
* using _drm_puts_coredump
*/
buf = kmalloc(len + 1, GFP_KERNEL | __GFP_NOWARN | __GFP_NORETRY);
if (!buf)
return;
snprintf(buf, len + 1, "%pV", vaf);
__drm_puts_coredump(p, (const char *) buf);
kfree(buf);
}
EXPORT_SYMBOL(__drm_printfn_coredump);
void __drm_puts_seq_file(struct drm_printer *p, const char *str)
{
seq_puts(p->arg, str);
}
EXPORT_SYMBOL(__drm_puts_seq_file);
void __drm_printfn_seq_file(struct drm_printer *p, struct va_format *vaf)
{
seq_printf(p->arg, "%pV", vaf);
}
EXPORT_SYMBOL(__drm_printfn_seq_file);
static void __drm_dev_vprintk(const struct device *dev, const char *level,
const void *origin, const char *prefix,
struct va_format *vaf)
{
const char *prefix_pad = prefix ? " " : "";
if (!prefix)
prefix = "";
if (dev) {
if (origin)
dev_printk(level, dev, "[" DRM_NAME ":%ps]%s%s %pV",
origin, prefix_pad, prefix, vaf);
else
dev_printk(level, dev, "[" DRM_NAME "]%s%s %pV",
prefix_pad, prefix, vaf);
} else {
if (origin)
printk("%s" "[" DRM_NAME ":%ps]%s%s %pV",
level, origin, prefix_pad, prefix, vaf);
else
printk("%s" "[" DRM_NAME "]%s%s %pV",
level, prefix_pad, prefix, vaf);
}
}
void __drm_printfn_info(struct drm_printer *p, struct va_format *vaf)
{
dev_info(p->arg, "[" DRM_NAME "] %pV", vaf);
}
EXPORT_SYMBOL(__drm_printfn_info);
void __drm_printfn_dbg(struct drm_printer *p, struct va_format *vaf)
{
const struct drm_device *drm = p->arg;
const struct device *dev = drm ? drm->dev : NULL;
enum drm_debug_category category = p->category;
if (!__drm_debug_enabled(category))
return;
__drm_dev_vprintk(dev, KERN_DEBUG, p->origin, p->prefix, vaf);
}
EXPORT_SYMBOL(__drm_printfn_dbg);
void __drm_printfn_err(struct drm_printer *p, struct va_format *vaf)
{
struct drm_device *drm = p->arg;
if (p->prefix)
drm_err(drm, "%s %pV", p->prefix, vaf);
else
drm_err(drm, "%pV", vaf);
}
EXPORT_SYMBOL(__drm_printfn_err);
/**
* drm_puts - print a const string to a &drm_printer stream
* @p: the &drm printer
* @str: const string
*
* Allow &drm_printer types that have a constant string
* option to use it.
*/
void drm_puts(struct drm_printer *p, const char *str)
{
if (p->puts)
p->puts(p, str);
else
drm_printf(p, "%s", str);
}
EXPORT_SYMBOL(drm_puts);
/**
* drm_printf - print to a &drm_printer stream
* @p: the &drm_printer
* @f: format string
*/
void drm_printf(struct drm_printer *p, const char *f, ...)
{
va_list args;
va_start(args, f);
drm_vprintf(p, f, &args);
va_end(args);
}
EXPORT_SYMBOL(drm_printf);
/**
* drm_print_bits - print bits to a &drm_printer stream
*
* Print bits (in flag fields for example) in human readable form.
*
* @p: the &drm_printer
* @value: field value.
* @bits: Array with bit names.
* @nbits: Size of bit names array.
*/
void drm_print_bits(struct drm_printer *p, unsigned long value,
const char * const bits[], unsigned int nbits)
{
bool first = true;
unsigned int i;
if (WARN_ON_ONCE(nbits > BITS_PER_TYPE(value)))
nbits = BITS_PER_TYPE(value);
for_each_set_bit(i, &value, nbits) {
if (WARN_ON_ONCE(!bits[i]))
continue;
drm_printf(p, "%s%s", first ? "" : ",",
bits[i]);
first = false;
}
if (first)
drm_printf(p, "(none)");
}
EXPORT_SYMBOL(drm_print_bits);
void drm_dev_printk(const struct device *dev, const char *level,
const char *format, ...)
{
struct va_format vaf;
va_list args;
va_start(args, format);
vaf.fmt = format;
vaf.va = &args;
__drm_dev_vprintk(dev, level, __builtin_return_address(0), NULL, &vaf);
va_end(args);
}
EXPORT_SYMBOL(drm_dev_printk);
void __drm_dev_dbg(struct _ddebug *desc, const struct device *dev,
enum drm_debug_category category, const char *format, ...)
{
struct va_format vaf;
va_list args;
if (!__drm_debug_enabled(category))
return;
/* we know we are printing for either syslog, tracefs, or both */
va_start(args, format);
vaf.fmt = format;
vaf.va = &args;
__drm_dev_vprintk(dev, KERN_DEBUG, __builtin_return_address(0), NULL, &vaf);
va_end(args);
}
EXPORT_SYMBOL(__drm_dev_dbg);
void __drm_err(const char *format, ...)
{
struct va_format vaf;
va_list args;
va_start(args, format);
vaf.fmt = format;
vaf.va = &args;
__drm_dev_vprintk(NULL, KERN_ERR, __builtin_return_address(0), "*ERROR*", &vaf);
va_end(args);
}
EXPORT_SYMBOL(__drm_err);
/**
* drm_print_regset32 - print the contents of registers to a
* &drm_printer stream.
*
* @p: the &drm printer
* @regset: the list of registers to print.
*
* Often in driver debug, it's useful to be able to either capture the
* contents of registers in the steady state using debugfs or at
* specific points during operation. This lets the driver have a
* single list of registers for both.
*/
void drm_print_regset32(struct drm_printer *p, struct debugfs_regset32 *regset)
{
int namelen = 0;
int i;
for (i = 0; i < regset->nregs; i++)
namelen = max(namelen, (int)strlen(regset->regs[i].name));
for (i = 0; i < regset->nregs; i++) {
drm_printf(p, "%*s = 0x%08x\n",
namelen, regset->regs[i].name,
readl(regset->base + regset->regs[i].offset));
}
}
EXPORT_SYMBOL(drm_print_regset32);