linux/include/drm/drm_print.h
Daniel Vetter c6603c740e drm: add managed resources tied to drm_device
We have lots of these. And the cleanup code tends to be of dubious
quality. The biggest wrong pattern is that developers use devm_, which
ties the release action to the underlying struct device, whereas
all the userspace visible stuff attached to a drm_device can long
outlive that one (e.g. after a hotunplug while userspace has open
files and mmap'ed buffers). Give people what they want, but with more
correctness.

Mostly copied from devres.c, with types adjusted to fit drm_device and
a few simplifications - I didn't (yet) copy over everything. Since
the types don't match code sharing looked like a hopeless endeavour.

For now it's only super simplified, no groups, you can't remove
actions (but kfree exists, we'll need that soon). Plus all specific to
drm_device ofc, including the logging. Which I didn't bother to make
compile-time optional, since none of the other drm logging is compile
time optional either.

One tricky bit here is the chicken&egg between allocating your
drm_device structure and initiliazing it with drm_dev_init. For
perfect onion unwinding we'd need to have the action to kfree the
allocation registered before drm_dev_init registers any of its own
release handlers. But drm_dev_init doesn't know where exactly the
drm_device is emebedded into the overall structure, and by the time it
returns it'll all be too late. And forcing drivers to be able clean up
everything except the one kzalloc is silly.

Work around this by having a very special final_kfree pointer. This
also avoids troubles with the list head possibly disappearing from
underneath us when we release all resources attached to the
drm_device.

v2: Do all the kerneldoc at the end, to avoid lots of fairly pointless
shuffling while getting everything into shape.

v3: Add static to add/del_dr (Neil)
Move typo fix to the right patch (Neil)

v4: Enforce contract for drmm_add_final_kfree:

Use ksize() to check that the drm_device is indeed contained somewhere
in the final kfree(). Because we need that or the entire managed
release logic blows up in a pile of use-after-frees. Motivated by a
discussion with Laurent.

v5: Review from Laurent:
- %zu instead of casting size_t
- header guards
- sorting of includes
- guarding of data assignment if we didn't allocate it for a NULL
  pointer
- delete spurious newline
- cast void* data parameter correctly in ->release call, no idea how
  this even worked before

v6: Review from Sam
- Add the kerneldoc for the managed sub-struct back in, even if it
  doesn't show up in the generated html somehow.
- Explain why __always_inline.
- Fix bisectability around the final kfree() in drm_dev_relase(). This
  is just interim code which will disappear again.
- Some whitespace polish.
- Add debug output when drmm_add_action or drmm_kmalloc fail.

v7: My bisectability fix wasn't up to par as noticed by smatch.

v8: Remove unecessary {} around if else

v9: Use kstrdup_const, which requires kfree_const and introducing a free_dr()
helper (Thomas).

v10: kfree_const goes boom on the plain "kmalloc" assignment, somehow
we need to wrap that in kstrdup_const() too!! Also renumber revision
log, I somehow reset it midway thruh.

Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Neil Armstrong <narmstrong@baylibre.com
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200324124540.3227396-1-daniel.vetter@ffwll.ch
2020-03-26 14:49:13 +01:00

553 lines
15 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>
*/
#ifndef DRM_PRINT_H_
#define DRM_PRINT_H_
#include <linux/compiler.h>
#include <linux/printk.h>
#include <linux/seq_file.h>
#include <linux/device.h>
#include <linux/debugfs.h>
#include <drm/drm.h>
/* Do *not* use outside of drm_print.[ch]! */
extern unsigned int __drm_debug;
/**
* DOC: print
*
* A simple wrapper for dev_printk(), seq_printf(), etc. Allows same
* debug code to be used for both debugfs and printk logging.
*
* For example::
*
* void log_some_info(struct drm_printer *p)
* {
* drm_printf(p, "foo=%d\n", foo);
* drm_printf(p, "bar=%d\n", bar);
* }
*
* #ifdef CONFIG_DEBUG_FS
* void debugfs_show(struct seq_file *f)
* {
* struct drm_printer p = drm_seq_file_printer(f);
* log_some_info(&p);
* }
* #endif
*
* void some_other_function(...)
* {
* struct drm_printer p = drm_info_printer(drm->dev);
* log_some_info(&p);
* }
*/
/**
* struct drm_printer - drm output "stream"
*
* Do not use struct members directly. Use drm_printer_seq_file(),
* drm_printer_info(), etc to initialize. And drm_printf() for output.
*/
struct drm_printer {
/* private: */
void (*printfn)(struct drm_printer *p, struct va_format *vaf);
void (*puts)(struct drm_printer *p, const char *str);
void *arg;
const char *prefix;
};
void __drm_printfn_coredump(struct drm_printer *p, struct va_format *vaf);
void __drm_puts_coredump(struct drm_printer *p, const char *str);
void __drm_printfn_seq_file(struct drm_printer *p, struct va_format *vaf);
void __drm_puts_seq_file(struct drm_printer *p, const char *str);
void __drm_printfn_info(struct drm_printer *p, struct va_format *vaf);
void __drm_printfn_debug(struct drm_printer *p, struct va_format *vaf);
void __drm_printfn_err(struct drm_printer *p, struct va_format *vaf);
__printf(2, 3)
void drm_printf(struct drm_printer *p, const char *f, ...);
void drm_puts(struct drm_printer *p, const char *str);
void drm_print_regset32(struct drm_printer *p, struct debugfs_regset32 *regset);
void drm_print_bits(struct drm_printer *p, unsigned long value,
const char * const bits[], unsigned int nbits);
__printf(2, 0)
/**
* drm_vprintf - print to a &drm_printer stream
* @p: the &drm_printer
* @fmt: format string
* @va: the va_list
*/
static inline void
drm_vprintf(struct drm_printer *p, const char *fmt, va_list *va)
{
struct va_format vaf = { .fmt = fmt, .va = va };
p->printfn(p, &vaf);
}
/**
* drm_printf_indent - Print to a &drm_printer stream with indentation
* @printer: DRM printer
* @indent: Tab indentation level (max 5)
* @fmt: Format string
*/
#define drm_printf_indent(printer, indent, fmt, ...) \
drm_printf((printer), "%.*s" fmt, (indent), "\t\t\t\t\tX", ##__VA_ARGS__)
/**
* struct drm_print_iterator - local struct used with drm_printer_coredump
* @data: Pointer to the devcoredump output buffer
* @start: The offset within the buffer to start writing
* @remain: The number of bytes to write for this iteration
*/
struct drm_print_iterator {
void *data;
ssize_t start;
ssize_t remain;
/* private: */
ssize_t offset;
};
/**
* drm_coredump_printer - construct a &drm_printer that can output to a buffer
* from the read function for devcoredump
* @iter: A pointer to a struct drm_print_iterator for the read instance
*
* This wrapper extends drm_printf() to work with a dev_coredumpm() callback
* function. The passed in drm_print_iterator struct contains the buffer
* pointer, size and offset as passed in from devcoredump.
*
* For example::
*
* void coredump_read(char *buffer, loff_t offset, size_t count,
* void *data, size_t datalen)
* {
* struct drm_print_iterator iter;
* struct drm_printer p;
*
* iter.data = buffer;
* iter.start = offset;
* iter.remain = count;
*
* p = drm_coredump_printer(&iter);
*
* drm_printf(p, "foo=%d\n", foo);
* }
*
* void makecoredump(...)
* {
* ...
* dev_coredumpm(dev, THIS_MODULE, data, 0, GFP_KERNEL,
* coredump_read, ...)
* }
*
* RETURNS:
* The &drm_printer object
*/
static inline struct drm_printer
drm_coredump_printer(struct drm_print_iterator *iter)
{
struct drm_printer p = {
.printfn = __drm_printfn_coredump,
.puts = __drm_puts_coredump,
.arg = iter,
};
/* Set the internal offset of the iterator to zero */
iter->offset = 0;
return p;
}
/**
* drm_seq_file_printer - construct a &drm_printer that outputs to &seq_file
* @f: the &struct seq_file to output to
*
* RETURNS:
* The &drm_printer object
*/
static inline struct drm_printer drm_seq_file_printer(struct seq_file *f)
{
struct drm_printer p = {
.printfn = __drm_printfn_seq_file,
.puts = __drm_puts_seq_file,
.arg = f,
};
return p;
}
/**
* drm_info_printer - construct a &drm_printer that outputs to dev_printk()
* @dev: the &struct device pointer
*
* RETURNS:
* The &drm_printer object
*/
static inline struct drm_printer drm_info_printer(struct device *dev)
{
struct drm_printer p = {
.printfn = __drm_printfn_info,
.arg = dev,
};
return p;
}
/**
* drm_debug_printer - construct a &drm_printer that outputs to pr_debug()
* @prefix: debug output prefix
*
* RETURNS:
* The &drm_printer object
*/
static inline struct drm_printer drm_debug_printer(const char *prefix)
{
struct drm_printer p = {
.printfn = __drm_printfn_debug,
.prefix = prefix
};
return p;
}
/**
* drm_err_printer - construct a &drm_printer that outputs to pr_err()
* @prefix: debug output prefix
*
* RETURNS:
* The &drm_printer object
*/
static inline struct drm_printer drm_err_printer(const char *prefix)
{
struct drm_printer p = {
.printfn = __drm_printfn_err,
.prefix = prefix
};
return p;
}
/**
* enum drm_debug_category - The DRM debug categories
*
* Each of the DRM debug logging macros use a specific category, and the logging
* is filtered by the drm.debug module parameter. This enum specifies the values
* for the interface.
*
* Each DRM_DEBUG_<CATEGORY> macro logs to DRM_UT_<CATEGORY> category, except
* DRM_DEBUG() logs to DRM_UT_CORE.
*
* Enabling verbose debug messages is done through the drm.debug parameter, each
* category being enabled by a bit:
*
* - drm.debug=0x1 will enable CORE messages
* - drm.debug=0x2 will enable DRIVER messages
* - drm.debug=0x3 will enable CORE and DRIVER messages
* - ...
* - drm.debug=0x1ff will enable all messages
*
* An interesting feature is that it's possible to enable verbose logging at
* run-time by echoing the debug value in its sysfs node::
*
* # echo 0xf > /sys/module/drm/parameters/debug
*
*/
enum drm_debug_category {
/**
* @DRM_UT_CORE: Used in the generic drm code: drm_ioctl.c, drm_mm.c,
* drm_memory.c, ...
*/
DRM_UT_CORE = 0x01,
/**
* @DRM_UT_DRIVER: Used in the vendor specific part of the driver: i915,
* radeon, ... macro.
*/
DRM_UT_DRIVER = 0x02,
/**
* @DRM_UT_KMS: Used in the modesetting code.
*/
DRM_UT_KMS = 0x04,
/**
* @DRM_UT_PRIME: Used in the prime code.
*/
DRM_UT_PRIME = 0x08,
/**
* @DRM_UT_ATOMIC: Used in the atomic code.
*/
DRM_UT_ATOMIC = 0x10,
/**
* @DRM_UT_VBL: Used for verbose debug message in the vblank code.
*/
DRM_UT_VBL = 0x20,
/**
* @DRM_UT_STATE: Used for verbose atomic state debugging.
*/
DRM_UT_STATE = 0x40,
/**
* @DRM_UT_LEASE: Used in the lease code.
*/
DRM_UT_LEASE = 0x80,
/**
* @DRM_UT_DP: Used in the DP code.
*/
DRM_UT_DP = 0x100,
/**
* @DRM_UT_DRMRES: Used in the drm managed resources code.
*/
DRM_UT_DRMRES = 0x200,
};
static inline bool drm_debug_enabled(enum drm_debug_category category)
{
return unlikely(__drm_debug & category);
}
/*
* struct device based logging
*
* Prefer drm_device based logging over device or prink based logging.
*/
__printf(3, 4)
void drm_dev_printk(const struct device *dev, const char *level,
const char *format, ...);
__printf(3, 4)
void drm_dev_dbg(const struct device *dev, enum drm_debug_category category,
const char *format, ...);
/**
* Error output.
*
* @dev: device pointer
* @fmt: printf() like format string.
*/
#define DRM_DEV_ERROR(dev, fmt, ...) \
drm_dev_printk(dev, KERN_ERR, "*ERROR* " fmt, ##__VA_ARGS__)
/**
* Rate limited error output. Like DRM_ERROR() but won't flood the log.
*
* @dev: device pointer
* @fmt: printf() like format string.
*/
#define DRM_DEV_ERROR_RATELIMITED(dev, fmt, ...) \
({ \
static DEFINE_RATELIMIT_STATE(_rs, \
DEFAULT_RATELIMIT_INTERVAL, \
DEFAULT_RATELIMIT_BURST); \
\
if (__ratelimit(&_rs)) \
DRM_DEV_ERROR(dev, fmt, ##__VA_ARGS__); \
})
#define DRM_DEV_INFO(dev, fmt, ...) \
drm_dev_printk(dev, KERN_INFO, fmt, ##__VA_ARGS__)
#define DRM_DEV_INFO_ONCE(dev, fmt, ...) \
({ \
static bool __print_once __read_mostly; \
if (!__print_once) { \
__print_once = true; \
DRM_DEV_INFO(dev, fmt, ##__VA_ARGS__); \
} \
})
/**
* Debug output.
*
* @dev: device pointer
* @fmt: printf() like format string.
*/
#define DRM_DEV_DEBUG(dev, fmt, ...) \
drm_dev_dbg(dev, DRM_UT_CORE, fmt, ##__VA_ARGS__)
#define DRM_DEV_DEBUG_DRIVER(dev, fmt, ...) \
drm_dev_dbg(dev, DRM_UT_DRIVER, fmt, ##__VA_ARGS__)
#define DRM_DEV_DEBUG_KMS(dev, fmt, ...) \
drm_dev_dbg(dev, DRM_UT_KMS, fmt, ##__VA_ARGS__)
/*
* struct drm_device based logging
*
* Prefer drm_device based logging over device or prink based logging.
*/
/* Helper for struct drm_device based logging. */
#define __drm_printk(drm, level, type, fmt, ...) \
dev_##level##type((drm)->dev, "[drm] " fmt, ##__VA_ARGS__)
#define drm_info(drm, fmt, ...) \
__drm_printk((drm), info,, fmt, ##__VA_ARGS__)
#define drm_notice(drm, fmt, ...) \
__drm_printk((drm), notice,, fmt, ##__VA_ARGS__)
#define drm_warn(drm, fmt, ...) \
__drm_printk((drm), warn,, fmt, ##__VA_ARGS__)
#define drm_err(drm, fmt, ...) \
__drm_printk((drm), err,, "*ERROR* " fmt, ##__VA_ARGS__)
#define drm_info_once(drm, fmt, ...) \
__drm_printk((drm), info, _once, fmt, ##__VA_ARGS__)
#define drm_notice_once(drm, fmt, ...) \
__drm_printk((drm), notice, _once, fmt, ##__VA_ARGS__)
#define drm_warn_once(drm, fmt, ...) \
__drm_printk((drm), warn, _once, fmt, ##__VA_ARGS__)
#define drm_err_once(drm, fmt, ...) \
__drm_printk((drm), err, _once, "*ERROR* " fmt, ##__VA_ARGS__)
#define drm_err_ratelimited(drm, fmt, ...) \
__drm_printk((drm), err, _ratelimited, "*ERROR* " fmt, ##__VA_ARGS__)
#define drm_dbg_core(drm, fmt, ...) \
drm_dev_dbg((drm)->dev, DRM_UT_CORE, fmt, ##__VA_ARGS__)
#define drm_dbg(drm, fmt, ...) \
drm_dev_dbg((drm)->dev, DRM_UT_DRIVER, fmt, ##__VA_ARGS__)
#define drm_dbg_kms(drm, fmt, ...) \
drm_dev_dbg((drm)->dev, DRM_UT_KMS, fmt, ##__VA_ARGS__)
#define drm_dbg_prime(drm, fmt, ...) \
drm_dev_dbg((drm)->dev, DRM_UT_PRIME, fmt, ##__VA_ARGS__)
#define drm_dbg_atomic(drm, fmt, ...) \
drm_dev_dbg((drm)->dev, DRM_UT_ATOMIC, fmt, ##__VA_ARGS__)
#define drm_dbg_vbl(drm, fmt, ...) \
drm_dev_dbg((drm)->dev, DRM_UT_VBL, fmt, ##__VA_ARGS__)
#define drm_dbg_state(drm, fmt, ...) \
drm_dev_dbg((drm)->dev, DRM_UT_STATE, fmt, ##__VA_ARGS__)
#define drm_dbg_lease(drm, fmt, ...) \
drm_dev_dbg((drm)->dev, DRM_UT_LEASE, fmt, ##__VA_ARGS__)
#define drm_dbg_dp(drm, fmt, ...) \
drm_dev_dbg((drm)->dev, DRM_UT_DP, fmt, ##__VA_ARGS__)
#define drm_dbg_drmres(drm, fmt, ...) \
drm_dev_dbg((drm)->dev, DRM_UT_DRMRES, fmt, ##__VA_ARGS__)
/*
* printk based logging
*
* Prefer drm_device based logging over device or prink based logging.
*/
__printf(2, 3)
void __drm_dbg(enum drm_debug_category category, const char *format, ...);
__printf(1, 2)
void __drm_err(const char *format, ...);
/* Macros to make printk easier */
#define _DRM_PRINTK(once, level, fmt, ...) \
printk##once(KERN_##level "[" DRM_NAME "] " fmt, ##__VA_ARGS__)
#define DRM_INFO(fmt, ...) \
_DRM_PRINTK(, INFO, fmt, ##__VA_ARGS__)
#define DRM_NOTE(fmt, ...) \
_DRM_PRINTK(, NOTICE, fmt, ##__VA_ARGS__)
#define DRM_WARN(fmt, ...) \
_DRM_PRINTK(, WARNING, fmt, ##__VA_ARGS__)
#define DRM_INFO_ONCE(fmt, ...) \
_DRM_PRINTK(_once, INFO, fmt, ##__VA_ARGS__)
#define DRM_NOTE_ONCE(fmt, ...) \
_DRM_PRINTK(_once, NOTICE, fmt, ##__VA_ARGS__)
#define DRM_WARN_ONCE(fmt, ...) \
_DRM_PRINTK(_once, WARNING, fmt, ##__VA_ARGS__)
#define DRM_ERROR(fmt, ...) \
__drm_err(fmt, ##__VA_ARGS__)
#define DRM_ERROR_RATELIMITED(fmt, ...) \
DRM_DEV_ERROR_RATELIMITED(NULL, fmt, ##__VA_ARGS__)
#define DRM_DEBUG(fmt, ...) \
__drm_dbg(DRM_UT_CORE, fmt, ##__VA_ARGS__)
#define DRM_DEBUG_DRIVER(fmt, ...) \
__drm_dbg(DRM_UT_DRIVER, fmt, ##__VA_ARGS__)
#define DRM_DEBUG_KMS(fmt, ...) \
__drm_dbg(DRM_UT_KMS, fmt, ##__VA_ARGS__)
#define DRM_DEBUG_PRIME(fmt, ...) \
__drm_dbg(DRM_UT_PRIME, fmt, ##__VA_ARGS__)
#define DRM_DEBUG_ATOMIC(fmt, ...) \
__drm_dbg(DRM_UT_ATOMIC, fmt, ##__VA_ARGS__)
#define DRM_DEBUG_VBL(fmt, ...) \
__drm_dbg(DRM_UT_VBL, fmt, ##__VA_ARGS__)
#define DRM_DEBUG_LEASE(fmt, ...) \
__drm_dbg(DRM_UT_LEASE, fmt, ##__VA_ARGS__)
#define DRM_DEBUG_DP(fmt, ...) \
__drm_dbg(DRM_UT_DP, fmt, ## __VA_ARGS__)
#define DRM_DEBUG_KMS_RATELIMITED(fmt, ...) \
({ \
static DEFINE_RATELIMIT_STATE(_rs, \
DEFAULT_RATELIMIT_INTERVAL, \
DEFAULT_RATELIMIT_BURST); \
if (__ratelimit(&_rs)) \
drm_dev_dbg(NULL, DRM_UT_KMS, fmt, ##__VA_ARGS__); \
})
/*
* struct drm_device based WARNs
*
* drm_WARN*() acts like WARN*(), but with the key difference of
* using device specific information so that we know from which device
* warning is originating from.
*
* Prefer drm_device based drm_WARN* over regular WARN*
*/
/* Helper for struct drm_device based WARNs */
#define drm_WARN(drm, condition, format, arg...) \
WARN(condition, "%s %s: " format, \
dev_driver_string((drm)->dev), \
dev_name((drm)->dev), ## arg)
#define drm_WARN_ONCE(drm, condition, format, arg...) \
WARN_ONCE(condition, "%s %s: " format, \
dev_driver_string((drm)->dev), \
dev_name((drm)->dev), ## arg)
#define drm_WARN_ON(drm, x) \
drm_WARN((drm), (x), "%s", \
"drm_WARN_ON(" __stringify(x) ")")
#define drm_WARN_ON_ONCE(drm, x) \
drm_WARN_ONCE((drm), (x), "%s", \
"drm_WARN_ON_ONCE(" __stringify(x) ")")
#endif /* DRM_PRINT_H_ */