spa_history.c File Reference

Routines to manage the on-disk history log. More...

#include <sys/spa.h>
#include <sys/spa_impl.h>
#include <sys/zap.h>
#include <sys/dsl_synctask.h>
#include <sys/dmu_tx.h>
#include <sys/dmu_objset.h>
#include <sys/utsname.h>
#include <sys/sunddi.h>
#include "zfs_comutil.h"
#include <sys/cmn_err.h>
#include <sys/zone.h>

Include dependency graph for spa_history.c:

Go to the source code of this file.

Functions
static uint64_t	spa_history_log_to_phys (uint64_t log_off, spa_history_phys_t *shpp)
	convert a logical offset to physical
void	spa_history_create_obj (spa_t *spa, dmu_tx_t *tx)
static int	spa_history_advance_bof (spa_t *spa, spa_history_phys_t *shpp)
	Change 'sh_bof' to the beginning of the next record.
static int	spa_history_write (spa_t *spa, void *buf, uint64_t len, spa_history_phys_t *shpp, dmu_tx_t *tx)
static char *	spa_history_zone ()
static void	spa_history_log_sync (void *arg1, void *arg2, dmu_tx_t *tx)
	Write out a history event.
int	spa_history_log (spa_t *spa, const char *history_str, history_log_type_t what)
	Write out a history event.
int	spa_history_get (spa_t *spa, uint64_t *offp, uint64_t *len, char *buf)
	Read out the command history.
static void	log_internal (history_internal_events_t event, spa_t *spa, dmu_tx_t *tx, const char *fmt, va_list adx)
void	spa_history_log_internal (history_internal_events_t event, spa_t *spa, dmu_tx_t *tx, const char *fmt,...)
void	spa_history_log_version (spa_t *spa, history_internal_events_t event)

---

Detailed Description

Routines to manage the on-disk history log.

The history log is stored as a dmu object containing <packed record length, record nvlist> tuples.

Where "record nvlist" is a nvlist containing uint64_ts and strings, and "packed record length" is the packed length of the "record nvlist" stored as a little endian uint64_t.

The log is implemented as a ring buffer, though the original creation of the pool ('zpool create') is never overwritten.

The history log is tracked as object 'spa_t::spa_history'. The bonus buffer of 'spa_history' stores the offsets for logging/retrieving history as 'spa_history_phys_t'. 'sh_pool_create_len' is the ending offset in bytes of where the 'zpool create' record is stored. This allows us to never overwrite the original creation of the pool. 'sh_phys_max_off' is the physical ending offset in bytes of the log. This tells you the length of the buffer. 'sh_eof' is the logical EOF (in bytes). Whenever a record is added, 'sh_eof' is incremented by the the size of the record. 'sh_eof' is never decremented. 'sh_bof' is the logical BOF (in bytes). This is where the consumer should start reading from after reading in the 'zpool create' portion of the log.

'sh_records_lost' keeps track of how many records have been overwritten and permanently lost.

Definition in file spa_history.c.

---

Function Documentation

static void log_internal	(	history_internal_events_t	event,
		spa_t *	spa,
		dmu_tx_t *	tx,
		const char *	fmt,
		va_list	adx
	)		[static]

Definition at line 435 of file spa_history.c.

static int spa_history_advance_bof	(	spa_t *	spa,
		spa_history_phys_t *	shpp
	)		[static]

Change 'sh_bof' to the beginning of the next record.

Definition at line 122 of file spa_history.c.

void spa_history_create_obj	(	spa_t *	spa,
		dmu_tx_t *	tx
	)

Definition at line 85 of file spa_history.c.

int spa_history_get	(	spa_t *	spa,
		uint64_t *	offp,
		uint64_t *	len,
		char *	buf
	)

Read out the command history.

Definition at line 341 of file spa_history.c.

int spa_history_log	(	spa_t *	spa,
		const char *	history_str,
		history_log_type_t	what
	)

Write out a history event.

Definition at line 304 of file spa_history.c.

void spa_history_log_internal	(	history_internal_events_t	event,
		spa_t *	spa,
		dmu_tx_t *	tx,
		const char *	fmt,
			...
	)

Definition at line 474 of file spa_history.c.

static void spa_history_log_sync	(	void *	arg1,
		void *	arg2,
		dmu_tx_t *	tx
	)		[static]

Write out a history event.

Definition at line 197 of file spa_history.c.

static uint64_t spa_history_log_to_phys	(	uint64_t	log_off,
		spa_history_phys_t *	shpp
	)		[static]

convert a logical offset to physical

Definition at line 75 of file spa_history.c.

void spa_history_log_version	(	spa_t *	spa,
		history_internal_events_t	event
	)

Definition at line 499 of file spa_history.c.

static int spa_history_write	(	spa_t *	spa,
		void *	buf,
		uint64_t	len,
		spa_history_phys_t *	shpp,
		dmu_tx_t *	tx
	)		[static]

Definition at line 149 of file spa_history.c.

static char* spa_history_zone

(

)

[static]

Definition at line 182 of file spa_history.c.