mars/kernel/mars.h
2017-05-04 09:16:17 +02:00

493 lines
14 KiB
C

/*
* MARS Long Distance Replication Software
*
* This file is part of MARS project: http://schoebel.github.io/mars/
*
* Copyright (C) 2010-2014 Thomas Schoebel-Theuer
* Copyright (C) 2011-2014 1&1 Internet AG
*
* This program 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.
*
* This program 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 this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#ifndef MARS_H
#define MARS_H
/* TRANSITIONAL compatibility to BOTH the old prepatch
* and the new wrapper around vfs_*(). Both will be replaced
* for kernel upstream.
*/
#include "compat.h"
#include <linux/semaphore.h>
#include <linux/rwsem.h>
#include <linux/major.h>
//#define MARS_TRACING // write runtime trace data to /mars/trace.csv
// check the Kconfig environment
#ifndef CONFIG_MARS_MODULE
// when unsure, include faked config file
#include "mars_config.h"
#ifndef CONFIG_SMP
#warning CONFIG_SMP is not set -- are you SURE???
#endif
#endif
#ifndef CONFIG_64BIT
#error MARS is only tested under 64bit
#endif
#ifndef CONFIG_BLOCK
#error CONFIG_BLOCK must be set
#endif
#ifndef CONFIG_PROC_SYSCTL
#error CONFIG_PROC_SYSCTL must be set
#endif
#ifndef CONFIG_HIGH_RES_TIMERS
#error CONFIG_HIGH_RES_TIMERS must be set
#endif
#ifdef CONFIG_DEBUG_SLAB
#error Fixme: CONFIG_DEBUG_SLAB does not work (fix the bio offset calculation)
#endif
#ifdef CONFIG_DEBUG_SG
#error Fixme: CONFIG_DEBUG_SG does not work (fix the bio offset calculation)
#endif
/////////////////////////////////////////////////////////////////////////
// include the generic brick infrastructure
#define OBJ_TYPE_MREF 0
#define OBJ_TYPE_MAX 1
#include "brick.h"
#include "brick_mem.h"
#include "brick_atomic.h"
#include "lamport.h"
#include "lib_timing.h"
#define GFP_MARS GFP_BRICK
/////////////////////////////////////////////////////////////////////////
// MARS-specific debugging helpers
#define _MARS_MSG(_class, _dump, _fmt, _args...) \
brick_say(_class, _dump, "MARS", __BASE_FILE__, __LINE__, __FUNCTION__, _fmt, ##_args)
#define MARS_FAT(_fmt, _args...) _MARS_MSG(SAY_FATAL, true, _fmt, ##_args)
#define MARS_ERR(_fmt, _args...) _MARS_MSG(SAY_ERROR, false, _fmt, ##_args)
#define MARS_WRN(_fmt, _args...) _MARS_MSG(SAY_WARN, false, _fmt, ##_args)
#define MARS_INF(_fmt, _args...) _MARS_MSG(SAY_INFO, false, _fmt, ##_args)
#ifdef MARS_DEBUGGING
#define MARS_DBG(_fmt, _args...) _MARS_MSG(SAY_DEBUG, false, _fmt, ##_args)
#else
#define MARS_DBG(_args...) /**/
#endif
#ifdef IO_DEBUGGING
#define MARS_IO(_fmt, _args...) _MARS_MSG(SAY_DEBUG, false, _fmt, ##_args)
#else
#define MARS_IO(_args...) /*empty*/
#endif
#ifdef STAT_DEBUGGING
#ifdef MARS_DEBUGGING
# define MARS_STAT MARS_DBG
#else
# define MARS_STAT MARS_INF
#endif
#else
#define MARS_STAT(_args...) /*empty*/
#endif
/////////////////////////////////////////////////////////////////////////
// MARS-specific definitions
#define MARS_PRIO_HIGH -1
#define MARS_PRIO_NORMAL 0 // this is automatically used by memset()
#define MARS_PRIO_LOW 1
#define MARS_PRIO_NR 3
// object stuff
/* mref */
#define MREF_UPTODATE 1
#define MREF_READING 2
#define MREF_WRITING 4
extern const struct generic_object_type mref_type;
#ifdef MARS_TRACING
extern unsigned long long start_trace_clock;
#define MAX_TRACES 16
#define TRACING_INFO \
int ref_traces; \
unsigned long long ref_trace_stamp[MAX_TRACES]; \
const char *ref_trace_info[MAX_TRACES];
extern void _mars_log(char *buf, int len);
extern void mars_log(const char *fmt, ...);
extern void mars_trace(struct mref_object *mref, const char *info);
extern void mars_log_trace(struct mref_object *mref);
#else
#define TRACING_INFO /*empty*/
#define _mars_log(buf,len) /*empty*/
#define mars_log(fmt...) /*empty*/
#define mars_trace(mref,info) /*empty*/
#define mars_log_trace(mref) /*empty*/
#endif
#define MREF_OBJECT(OBJTYPE) \
CALLBACK_OBJECT(OBJTYPE); \
/* supplied by caller */ \
void *ref_data; /* preset to NULL for buffered IO */ \
loff_t ref_pos; \
int ref_len; \
int ref_may_write; \
int ref_prio; \
int ref_timeout; \
int ref_cs_mode; /* 0 = off, 1 = checksum + data, 2 = checksum only */ \
/* maintained by the ref implementation, readable for callers */ \
loff_t ref_total_size; /* just for info, need not be implemented */ \
unsigned char ref_checksum[16]; \
int ref_flags; \
int ref_rw; \
int ref_id; /* not mandatory; may be used for identification */ \
bool ref_skip_sync; /* skip sync for this particular mref */ \
/* maintained by the ref implementation, incrementable for \
* callers (but not decrementable! use ref_put()) */ \
bool ref_initialized; /* internally used for checking */ \
tatomic_t ref_count; \
/* internal */ \
atomic_trace_t ref_at; \
TRACING_INFO;
struct mref_object {
MREF_OBJECT(mref);
};
#define _mref_check(mref) \
({ \
if (unlikely(BRICK_CHECKING && !(mref)->ref_initialized)) { \
MARS_ERR("mref %p is not initialized\n", (mref)); \
} \
CHECK_TATOMIC(&(mref)->ref_at, &(mref)->ref_count, 1); \
})
#define _mref_get_first(mref) \
({ \
if (unlikely(BRICK_CHECKING && (mref)->ref_initialized)) { \
MARS_ERR("mref %p is already initialized\n", (mref)); \
} \
_CHECK_TATOMIC(&(mref)->ref_at, &(mref)->ref_count, !=, 0, 0); \
(mref)->ref_initialized = true; \
tatomic_inc(&(mref)->ref_at, &(mref)->ref_count); \
})
#define _mref_get(mref) \
({ \
_mref_check(mref); \
tatomic_inc(&(mref)->ref_at, &(mref)->ref_count); \
})
#define _mref_put(mref) \
({ \
_mref_check(mref); \
tatomic_dec_and_test(&(mref)->ref_at, &(mref)->ref_count); \
})
// internal helper structs
struct mars_info {
loff_t current_size;
int tf_align; // transfer alignment constraint
int tf_min_size; // transfer is only possible in multiples of this
};
// brick stuff
#define MARS_BRICK(BRITYPE) \
GENERIC_BRICK(BRITYPE); \
struct generic_object_layout mref_object_layout; \
struct list_head global_brick_link; \
struct list_head dent_brick_link; \
const char *brick_path; \
struct mars_global *global; \
struct timespec create_stamp; \
void **kill_ptr; \
int *mode_ptr; \
int kill_round; \
bool killme; \
void (*show_status)(struct mars_brick *brick, bool shutdown); \
struct mars_brick {
MARS_BRICK(mars);
};
#define MARS_INPUT(BRITYPE) \
GENERIC_INPUT(BRITYPE); \
struct mars_input {
MARS_INPUT(mars);
};
#define MARS_OUTPUT(BRITYPE) \
GENERIC_OUTPUT(BRITYPE); \
struct mars_output {
MARS_OUTPUT(mars);
};
#define MARS_BRICK_OPS(BRITYPE) \
GENERIC_BRICK_OPS(BRITYPE); \
char *(*brick_statistics)(struct BRITYPE##_brick *brick, int verbose); \
void (*reset_statistics)(struct BRITYPE##_brick *brick); \
#define MARS_OUTPUT_OPS(BRITYPE) \
GENERIC_OUTPUT_OPS(BRITYPE); \
int (*mars_get_info)(struct BRITYPE##_output *output, struct mars_info *info); \
/* mref */ \
int (*mref_get)(struct BRITYPE##_output *output, struct mref_object *mref); \
void (*mref_io)(struct BRITYPE##_output *output, struct mref_object *mref); \
void (*mref_put)(struct BRITYPE##_output *output, struct mref_object *mref); \
// all non-extendable types
#define _MARS_TYPES(BRITYPE) \
\
struct BRITYPE##_brick_ops { \
MARS_BRICK_OPS(BRITYPE); \
}; \
\
struct BRITYPE##_output_ops { \
MARS_OUTPUT_OPS(BRITYPE); \
}; \
\
struct BRITYPE##_brick_type { \
GENERIC_BRICK_TYPE(BRITYPE); \
}; \
\
struct BRITYPE##_input_type { \
GENERIC_INPUT_TYPE(BRITYPE); \
}; \
\
struct BRITYPE##_output_type { \
GENERIC_OUTPUT_TYPE(BRITYPE); \
}; \
\
struct BRITYPE##_callback { \
GENERIC_CALLBACK(BRITYPE); \
}; \
\
DECLARE_BRICK_FUNCTIONS(BRITYPE); \
#define MARS_TYPES(BRITYPE) \
\
_MARS_TYPES(BRITYPE) \
\
DECLARE_ASPECT_FUNCTIONS(BRITYPE,mref); \
extern int init_mars_##BRITYPE(void); \
extern void exit_mars_##BRITYPE(void);
// instantiate a pseudo base-class "mars"
_MARS_TYPES(mars);
DECLARE_ASPECT_FUNCTIONS(mars,mref);
/////////////////////////////////////////////////////////////////////////
// MARS-specific helpers
#define MARS_MAKE_STATICS(BRITYPE) \
\
int BRITYPE##_brick_nr = -EEXIST; \
EXPORT_SYMBOL_GPL(BRITYPE##_brick_nr); \
\
static const struct generic_aspect_type BRITYPE##_mref_aspect_type = { \
.aspect_type_name = #BRITYPE "_mref_aspect_type", \
.object_type = &mref_type, \
.aspect_size = sizeof(struct BRITYPE##_mref_aspect), \
.init_fn = BRITYPE##_mref_aspect_init_fn, \
.exit_fn = BRITYPE##_mref_aspect_exit_fn, \
}; \
\
static const struct generic_aspect_type *BRITYPE##_aspect_types[OBJ_TYPE_MAX] = { \
[OBJ_TYPE_MREF] = &BRITYPE##_mref_aspect_type, \
}; \
extern const struct meta mars_info_meta[];
extern const struct meta mars_mref_meta[];
extern const struct meta mars_timespec_meta[];
/////////////////////////////////////////////////////////////////////////
#ifdef _STRATEGY
#include "sy_old/strategy.h"
#endif
extern void mars_power_led_on(struct mars_brick *brick, bool val);
extern void mars_power_led_off(struct mars_brick *brick, bool val);
/* this should disappear!
*/
extern void (*_mars_trigger)(void);
extern void (*_mars_remote_trigger)(void);
#define mars_trigger() do { if (_mars_trigger) { MARS_DBG("trigger...\n"); _mars_trigger(); } } while (0)
#define mars_remote_trigger() do { if (_mars_remote_trigger) { MARS_DBG("remote_trigger...\n"); _mars_remote_trigger(); } } while (0)
/////////////////////////////////////////////////////////////////////////
/* Some global stuff.
*/
extern struct banning mars_global_ban;
extern atomic_t mars_global_io_flying;
extern int mars_throttle_start;
extern int mars_throttle_end;
/////////////////////////////////////////////////////////////////////////
/* Some special brick types for avoidance of cyclic references.
*
* The client/server network bricks use this for independent instantiation
* from the main instantiation logic (separate modprobe for mars_server
* is possible).
*/
extern const struct generic_brick_type *_client_brick_type;
extern const struct generic_brick_type *_bio_brick_type;
extern const struct generic_brick_type *_aio_brick_type;
extern const struct generic_brick_type *_sio_brick_type;
#if !defined(CONFIG_MARS_PREFER_SIO) && defined(HAS_MARS_PREPATCH)
#define ENABLE_MARS_AIO
#endif
#ifdef ENABLE_MARS_AIO
/* Kludge: our kernel threads will have no mm context, but need one
* for stuff like ioctx_alloc() / aio_setup_ring() etc
* which expect userspace resources.
* We fake one.
* TODO: factor out the userspace stuff from AIO such that
* this fake is no longer necessary.
* Even better: replace do_mmap() in AIO stuff by something
* more friendly to kernelspace apps.
*/
#include <linux/mmu_context.h>
extern struct mm_struct *mm_fake;
extern struct task_struct *mm_fake_task;
extern atomic_t mm_fake_count;
static inline void set_fake(void)
{
mm_fake = current->mm;
if (mm_fake) {
MARS_DBG("initialized fake\n");
mm_fake_task = current;
get_task_struct(current); // paired with put_task_struct()
atomic_inc(&mm_fake->mm_count); // paired with mmdrop()
atomic_inc(&mm_fake->mm_users); // paired with mmput()
}
}
static inline void put_fake(void)
{
if (mm_fake && mm_fake_task) {
int remain = atomic_read(&mm_fake_count);
if (unlikely(remain != 0)) {
MARS_ERR("cannot cleanup fake, remain = %d\n", remain);
} else {
MARS_DBG("cleaning up fake\n");
mmput(mm_fake);
mmdrop(mm_fake);
mm_fake = NULL;
put_task_struct(mm_fake_task);
mm_fake_task = NULL;
}
}
}
static inline void use_fake_mm(void)
{
if (!current->mm && mm_fake) {
atomic_inc(&mm_fake_count);
MARS_DBG("using fake, count=%d\n", atomic_read(&mm_fake_count));
use_mm(mm_fake);
}
}
/* Cleanup faked mm, otherwise do_exit() will crash
*/
static inline void unuse_fake_mm(void)
{
if (current->mm == mm_fake && mm_fake) {
MARS_DBG("unusing fake, count=%d\n", atomic_read(&mm_fake_count));
atomic_dec(&mm_fake_count);
unuse_mm(mm_fake);
current->mm = NULL;
}
}
#else
static inline void set_fake(void) {}
static inline void put_fake(void) {}
static inline void use_fake_mm(void) {}
static inline void unuse_fake_mm(void) {}
#endif
/////////////////////////////////////////////////////////////////////////
/* Crypto stuff
*/
extern int mars_digest_size;
extern void mars_digest(unsigned char *digest, void *data, int len);
extern void mref_checksum(struct mref_object *mref);
/////////////////////////////////////////////////////////////////////////
/* Crash-testing instrumentation.
* Only for debugging. Never use this for production.
* Simulate a crash at the "wrong moment".
*/
#ifdef CONFIG_MARS_DEBUG
extern int mars_crash_mode;
extern int mars_hang_mode;
extern void _crashme(int mode, bool do_sync);
#else
extern inline void _crashme(int mode, bool do_sync) {}
#endif
/////////////////////////////////////////////////////////////////////////
// init
extern int init_mars(void);
extern void exit_mars(void);
#endif