[deliverable/linux.git] / fs / ext4 / ext4_jbd2.c

/*
 * Interface between ext4 and JBD
 */

#include "ext4_jbd2.h"

#include <trace/events/ext4.h>

/* Just increment the non-pointer handle value */
static handle_t *ext4_get_nojournal(void)
{
	handle_t *handle = current->journal_info;
	unsigned long ref_cnt = (unsigned long)handle;

	BUG_ON(ref_cnt >= EXT4_NOJOURNAL_MAX_REF_COUNT);

	ref_cnt++;
	handle = (handle_t *)ref_cnt;

	current->journal_info = handle;
	return handle;
}


/* Decrement the non-pointer handle value */
static void ext4_put_nojournal(handle_t *handle)
{
	unsigned long ref_cnt = (unsigned long)handle;

	BUG_ON(ref_cnt == 0);

	ref_cnt--;
	handle = (handle_t *)ref_cnt;

	current->journal_info = handle;
}

/*
 * Wrappers for jbd2_journal_start/end.
 */
static int ext4_journal_check_start(struct super_block *sb)
{
	journal_t *journal;

	might_sleep();
	if (sb->s_flags & MS_RDONLY)
		return -EROFS;
	WARN_ON(sb->s_writers.frozen == SB_FREEZE_COMPLETE);
	journal = EXT4_SB(sb)->s_journal;
	/*
	 * Special case here: if the journal has aborted behind our
	 * backs (eg. EIO in the commit thread), then we still need to
	 * take the FS itself readonly cleanly.
	 */
	if (journal && is_journal_aborted(journal)) {
		ext4_abort(sb, "Detected aborted journal");
		return -EROFS;
	}
	return 0;
}

handle_t *__ext4_journal_start_sb(struct super_block *sb, unsigned int line,
				  int type, int blocks, int rsv_blocks)
{
	journal_t *journal;
	int err;

	trace_ext4_journal_start(sb, blocks, rsv_blocks, _RET_IP_);
	err = ext4_journal_check_start(sb);
	if (err < 0)
		return ERR_PTR(err);

	journal = EXT4_SB(sb)->s_journal;
	if (!journal)
		return ext4_get_nojournal();
	return jbd2__journal_start(journal, blocks, rsv_blocks, GFP_NOFS,
				   type, line);
}

int __ext4_journal_stop(const char *where, unsigned int line, handle_t *handle)
{
	struct super_block *sb;
	int err;
	int rc;

	if (!ext4_handle_valid(handle)) {
		ext4_put_nojournal(handle);
		return 0;
	}
	sb = handle->h_transaction->t_journal->j_private;
	err = handle->h_err;
	rc = jbd2_journal_stop(handle);

	if (!err)
		err = rc;
	if (err)
		__ext4_std_error(sb, where, line, err);
	return err;
}

handle_t *__ext4_journal_start_reserved(handle_t *handle, unsigned int line,
					int type)
{
	struct super_block *sb;
	int err;

	if (!ext4_handle_valid(handle))
		return ext4_get_nojournal();

	sb = handle->h_journal->j_private;
	trace_ext4_journal_start_reserved(sb, handle->h_buffer_credits,
					  _RET_IP_);
	err = ext4_journal_check_start(sb);
	if (err < 0) {
		jbd2_journal_free_reserved(handle);
		return ERR_PTR(err);
	}

	err = jbd2_journal_start_reserved(handle, type, line);
	if (err < 0)
		return ERR_PTR(err);
	return handle;
}

void ext4_journal_abort_handle(const char *caller, unsigned int line,
			       const char *err_fn, struct buffer_head *bh,
			       handle_t *handle, int err)
{
	char nbuf[16];
	const char *errstr = ext4_decode_error(NULL, err, nbuf);

	BUG_ON(!ext4_handle_valid(handle));

	if (bh)
		BUFFER_TRACE(bh, "abort");

	if (!handle->h_err)
		handle->h_err = err;

	if (is_handle_aborted(handle))
		return;

	printk(KERN_ERR "EXT4-fs: %s:%d: aborting transaction: %s in %s\n",
	       caller, line, errstr, err_fn);

	jbd2_journal_abort_handle(handle);
}

int __ext4_journal_get_write_access(const char *where, unsigned int line,
				    handle_t *handle, struct buffer_head *bh)
{
	int err = 0;

	might_sleep();

	if (ext4_handle_valid(handle)) {
		err = jbd2_journal_get_write_access(handle, bh);
		if (err)
			ext4_journal_abort_handle(where, line, __func__, bh,
						  handle, err);
	}
	return err;
}

/*
 * The ext4 forget function must perform a revoke if we are freeing data
 * which has been journaled.  Metadata (eg. indirect blocks) must be
 * revoked in all cases.
 *
 * "bh" may be NULL: a metadata block may have been freed from memory
 * but there may still be a record of it in the journal, and that record
 * still needs to be revoked.
 *
 * If the handle isn't valid we're not journaling, but we still need to
 * call into ext4_journal_revoke() to put the buffer head.
 */
int __ext4_forget(const char *where, unsigned int line, handle_t *handle,
		  int is_metadata, struct inode *inode,
		  struct buffer_head *bh, ext4_fsblk_t blocknr)
{
	int err;

	might_sleep();

	trace_ext4_forget(inode, is_metadata, blocknr);
	BUFFER_TRACE(bh, "enter");

	jbd_debug(4, "forgetting bh %p: is_metadata = %d, mode %o, "
		  "data mode %x\n",
		  bh, is_metadata, inode->i_mode,
		  test_opt(inode->i_sb, DATA_FLAGS));

	/* In the no journal case, we can just do a bforget and return */
	if (!ext4_handle_valid(handle)) {
		bforget(bh);
		return 0;
	}

	/* Never use the revoke function if we are doing full data
	 * journaling: there is no need to, and a V1 superblock won't
	 * support it.  Otherwise, only skip the revoke on un-journaled
	 * data blocks. */

	if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA ||
	    (!is_metadata && !ext4_should_journal_data(inode))) {
		if (bh) {
			BUFFER_TRACE(bh, "call jbd2_journal_forget");
			err = jbd2_journal_forget(handle, bh);
			if (err)
				ext4_journal_abort_handle(where, line, __func__,
							  bh, handle, err);
			return err;
		}
		return 0;
	}

	/*
	 * data!=journal && (is_metadata || should_journal_data(inode))
	 */
	BUFFER_TRACE(bh, "call jbd2_journal_revoke");
	err = jbd2_journal_revoke(handle, blocknr, bh);
	if (err) {
		ext4_journal_abort_handle(where, line, __func__,
					  bh, handle, err);
		__ext4_abort(inode->i_sb, where, line,
			   "error %d when attempting revoke", err);
	}
	BUFFER_TRACE(bh, "exit");
	return err;
}

int __ext4_journal_get_create_access(const char *where, unsigned int line,
				handle_t *handle, struct buffer_head *bh)
{
	int err = 0;

	if (ext4_handle_valid(handle)) {
		err = jbd2_journal_get_create_access(handle, bh);
		if (err)
			ext4_journal_abort_handle(where, line, __func__,
						  bh, handle, err);
	}
	return err;
}

int __ext4_handle_dirty_metadata(const char *where, unsigned int line,
				 handle_t *handle, struct inode *inode,
				 struct buffer_head *bh)
{
	int err = 0;

	might_sleep();

	set_buffer_meta(bh);
	set_buffer_prio(bh);
	if (ext4_handle_valid(handle)) {
		err = jbd2_journal_dirty_metadata(handle, bh);
		/* Errors can only happen if there is a bug */
		if (WARN_ON_ONCE(err)) {
			ext4_journal_abort_handle(where, line, __func__, bh,
						  handle, err);
			ext4_error_inode(inode, where, line,
					 bh->b_blocknr,
					 "journal_dirty_metadata failed: "
					 "handle type %u started at line %u, "
					 "credits %u/%u, errcode %d",
					 handle->h_type,
					 handle->h_line_no,
					 handle->h_requested_credits,
					 handle->h_buffer_credits, err);
		}
	} else {
		if (inode)
			mark_buffer_dirty_inode(bh, inode);
		else
			mark_buffer_dirty(bh);
		if (inode && inode_needs_sync(inode)) {
			sync_dirty_buffer(bh);
			if (buffer_req(bh) && !buffer_uptodate(bh)) {
				struct ext4_super_block *es;

				es = EXT4_SB(inode->i_sb)->s_es;
				es->s_last_error_block =
					cpu_to_le64(bh->b_blocknr);
				ext4_error_inode(inode, where, line,
						 bh->b_blocknr,
					"IO error syncing itable block");
				err = -EIO;
			}
		}
	}
	return err;
}

int __ext4_handle_dirty_super(const char *where, unsigned int line,
			      handle_t *handle, struct super_block *sb)
{
	struct buffer_head *bh = EXT4_SB(sb)->s_sbh;
	int err = 0;

	ext4_superblock_csum_set(sb);
	if (ext4_handle_valid(handle)) {
		err = jbd2_journal_dirty_metadata(handle, bh);
		if (err)
			ext4_journal_abort_handle(where, line, __func__,
						  bh, handle, err);
	} else
		mark_buffer_dirty(bh);
	return err;
}
Commit	Line	Data
8984d137 AM	1	/*
	2	* Interface between ext4 and JBD
	3	*/
	4
3dcf5451	5	#include "ext4_jbd2.h"
8984d137	6
d6797d14 TT	7	#include <trace/events/ext4.h>
d6797d14 TT	8
722887dd TT	9	/* Just increment the non-pointer handle value */
	10	static handle_t *ext4_get_nojournal(void)
	11	{
	12	handle_t *handle = current->journal_info;
	13	unsigned long ref_cnt = (unsigned long)handle;
	14
	15	BUG_ON(ref_cnt >= EXT4_NOJOURNAL_MAX_REF_COUNT);
	16
	17	ref_cnt++;
	18	handle = (handle_t *)ref_cnt;
	19
	20	current->journal_info = handle;
	21	return handle;
	22	}
	23
	24
	25	/* Decrement the non-pointer handle value */
	26	static void ext4_put_nojournal(handle_t *handle)
	27	{
	28	unsigned long ref_cnt = (unsigned long)handle;
	29
	30	BUG_ON(ref_cnt == 0);
	31
	32	ref_cnt--;
	33	handle = (handle_t *)ref_cnt;
	34
	35	current->journal_info = handle;
	36	}
	37
	38	/*
	39	* Wrappers for jbd2_journal_start/end.
	40	*/
5fe2fe89	41	static int ext4_journal_check_start(struct super_block *sb)
722887dd TT	42	{
	43	journal_t *journal;
	44
b10a44c3	45	might_sleep();
722887dd	46	if (sb->s_flags & MS_RDONLY)
5fe2fe89	47	return -EROFS;
722887dd TT	48	WARN_ON(sb->s_writers.frozen == SB_FREEZE_COMPLETE);
722887dd TT	49	journal = EXT4_SB(sb)->s_journal;
722887dd TT	50	/*
	51	* Special case here: if the journal has aborted behind our
	52	* backs (eg. EIO in the commit thread), then we still need to
	53	* take the FS itself readonly cleanly.
	54	*/
5fe2fe89	55	if (journal && is_journal_aborted(journal)) {
722887dd	56	ext4_abort(sb, "Detected aborted journal");
5fe2fe89	57	return -EROFS;
722887dd	58	}
5fe2fe89 JK	59	return 0;
	60	}
	61
	62	handle_t __ext4_journal_start_sb(struct super_block sb, unsigned int line,
	63	int type, int blocks, int rsv_blocks)
	64	{
	65	journal_t *journal;
	66	int err;
	67
	68	trace_ext4_journal_start(sb, blocks, rsv_blocks, _RET_IP_);
	69	err = ext4_journal_check_start(sb);
	70	if (err < 0)
	71	return ERR_PTR(err);
	72
	73	journal = EXT4_SB(sb)->s_journal;
	74	if (!journal)
	75	return ext4_get_nojournal();
	76	return jbd2__journal_start(journal, blocks, rsv_blocks, GFP_NOFS,
	77	type, line);
722887dd TT	78	}
	79
	80	int __ext4_journal_stop(const char where, unsigned int line, handle_t handle)
	81	{
	82	struct super_block *sb;
	83	int err;
	84	int rc;
	85
	86	if (!ext4_handle_valid(handle)) {
	87	ext4_put_nojournal(handle);
	88	return 0;
	89	}
	90	sb = handle->h_transaction->t_journal->j_private;
	91	err = handle->h_err;
	92	rc = jbd2_journal_stop(handle);
	93
	94	if (!err)
	95	err = rc;
	96	if (err)
	97	__ext4_std_error(sb, where, line, err);
	98	return err;
	99	}
	100
5fe2fe89 JK	101	handle_t __ext4_journal_start_reserved(handle_t handle, unsigned int line,
	102	int type)
	103	{
	104	struct super_block *sb;
	105	int err;
	106
	107	if (!ext4_handle_valid(handle))
	108	return ext4_get_nojournal();
	109
	110	sb = handle->h_journal->j_private;
	111	trace_ext4_journal_start_reserved(sb, handle->h_buffer_credits,
	112	_RET_IP_);
	113	err = ext4_journal_check_start(sb);
	114	if (err < 0) {
	115	jbd2_journal_free_reserved(handle);
	116	return ERR_PTR(err);
	117	}
	118
	119	err = jbd2_journal_start_reserved(handle, type, line);
	120	if (err < 0)
	121	return ERR_PTR(err);
	122	return handle;
	123	}
	124
722887dd TT	125	void ext4_journal_abort_handle(const char *caller, unsigned int line,
	126	const char err_fn, struct buffer_head bh,
	127	handle_t *handle, int err)
	128	{
	129	char nbuf[16];
	130	const char *errstr = ext4_decode_error(NULL, err, nbuf);
	131
	132	BUG_ON(!ext4_handle_valid(handle));
	133
	134	if (bh)
	135	BUFFER_TRACE(bh, "abort");
	136
	137	if (!handle->h_err)
	138	handle->h_err = err;
	139
	140	if (is_handle_aborted(handle))
	141	return;
	142
	143	printk(KERN_ERR "EXT4-fs: %s:%d: aborting transaction: %s in %s\n",
	144	caller, line, errstr, err_fn);
	145
	146	jbd2_journal_abort_handle(handle);
	147	}
	148
90c7201b TT	149	int __ext4_journal_get_write_access(const char *where, unsigned int line,
90c7201b TT	150	handle_t handle, struct buffer_head bh)
8984d137	151	{
0390131b FM	152	int err = 0;
0390131b FM	153
b10a44c3 TT	154	might_sleep();
b10a44c3 TT	155
0390131b FM	156	if (ext4_handle_valid(handle)) {
	157	err = jbd2_journal_get_write_access(handle, bh);
	158	if (err)
90c7201b	159	ext4_journal_abort_handle(where, line, __func__, bh,
0390131b FM	160	handle, err);
0390131b FM	161	}
8984d137 AM	162	return err;
	163	}
	164
d6797d14 TT	165	/*
	166	* The ext4 forget function must perform a revoke if we are freeing data
	167	* which has been journaled. Metadata (eg. indirect blocks) must be
	168	* revoked in all cases.
	169	*
	170	* "bh" may be NULL: a metadata block may have been freed from memory
	171	* but there may still be a record of it in the journal, and that record
	172	* still needs to be revoked.
	173	*
	174	* If the handle isn't valid we're not journaling, but we still need to
	175	* call into ext4_journal_revoke() to put the buffer head.
	176	*/
90c7201b TT	177	int __ext4_forget(const char where, unsigned int line, handle_t handle,
	178	int is_metadata, struct inode *inode,
	179	struct buffer_head *bh, ext4_fsblk_t blocknr)
d6797d14 TT	180	{
	181	int err;
	182
	183	might_sleep();
	184
	185	trace_ext4_forget(inode, is_metadata, blocknr);
	186	BUFFER_TRACE(bh, "enter");
	187
	188	jbd_debug(4, "forgetting bh %p: is_metadata = %d, mode %o, "
	189	"data mode %x\n",
	190	bh, is_metadata, inode->i_mode,
	191	test_opt(inode->i_sb, DATA_FLAGS));
	192
e4684b3f TT	193	/* In the no journal case, we can just do a bforget and return */
	194	if (!ext4_handle_valid(handle)) {
	195	bforget(bh);
	196	return 0;
	197	}
	198
d6797d14 TT	199	/* Never use the revoke function if we are doing full data
	200	* journaling: there is no need to, and a V1 superblock won't
	201	* support it. Otherwise, only skip the revoke on un-journaled
	202	* data blocks. */
	203
	204	if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA \|\|
	205	(!is_metadata && !ext4_should_journal_data(inode))) {
	206	if (bh) {
	207	BUFFER_TRACE(bh, "call jbd2_journal_forget");
b7e57e7c TT	208	err = jbd2_journal_forget(handle, bh);
b7e57e7c TT	209	if (err)
90c7201b TT	210	ext4_journal_abort_handle(where, line, __func__,
90c7201b TT	211	bh, handle, err);
b7e57e7c	212	return err;
d6797d14 TT	213	}
	214	return 0;
	215	}
	216
	217	/*
	218	* data!=journal && (is_metadata \|\| should_journal_data(inode))
	219	*/
e4684b3f TT	220	BUFFER_TRACE(bh, "call jbd2_journal_revoke");
	221	err = jbd2_journal_revoke(handle, blocknr, bh);
	222	if (err) {
90c7201b TT	223	ext4_journal_abort_handle(where, line, __func__,
90c7201b TT	224	bh, handle, err);
c398eda0 TT	225	__ext4_abort(inode->i_sb, where, line,
c398eda0 TT	226	"error %d when attempting revoke", err);
e4684b3f	227	}
d6797d14 TT	228	BUFFER_TRACE(bh, "exit");
	229	return err;
	230	}
	231
90c7201b	232	int __ext4_journal_get_create_access(const char *where, unsigned int line,
8984d137 AM	233	handle_t handle, struct buffer_head bh)
8984d137 AM	234	{
0390131b FM	235	int err = 0;
	236
	237	if (ext4_handle_valid(handle)) {
	238	err = jbd2_journal_get_create_access(handle, bh);
	239	if (err)
90c7201b TT	240	ext4_journal_abort_handle(where, line, __func__,
90c7201b TT	241	bh, handle, err);
0390131b	242	}
8984d137 AM	243	return err;
	244	}
	245
90c7201b TT	246	int __ext4_handle_dirty_metadata(const char *where, unsigned int line,
	247	handle_t handle, struct inode inode,
	248	struct buffer_head *bh)
8984d137	249	{
0390131b FM	250	int err = 0;
0390131b FM	251
b10a44c3 TT	252	might_sleep();
b10a44c3 TT	253
13fca323 TT	254	set_buffer_meta(bh);
13fca323 TT	255	set_buffer_prio(bh);
0390131b FM	256	if (ext4_handle_valid(handle)) {
0390131b FM	257	err = jbd2_journal_dirty_metadata(handle, bh);
91aa11fa JK	258	/* Errors can only happen if there is a bug */
	259	if (WARN_ON_ONCE(err)) {
	260	ext4_journal_abort_handle(where, line, __func__, bh,
	261	handle, err);
ae1495b1 TT	262	ext4_error_inode(inode, where, line,
	263	bh->b_blocknr,
	264	"journal_dirty_metadata failed: "
	265	"handle type %u started at line %u, "
	266	"credits %u/%u, errcode %d",
	267	handle->h_type,
	268	handle->h_line_no,
	269	handle->h_requested_credits,
	270	handle->h_buffer_credits, err);
9ea7a0df	271	}
0390131b	272	} else {
73b50c1c	273	if (inode)
fe188c0e TT	274	mark_buffer_dirty_inode(bh, inode);
	275	else
	276	mark_buffer_dirty(bh);
0390131b FM	277	if (inode && inode_needs_sync(inode)) {
	278	sync_dirty_buffer(bh);
	279	if (buffer_req(bh) && !buffer_uptodate(bh)) {
1c13d5c0 TT	280	struct ext4_super_block *es;
	281
	282	es = EXT4_SB(inode->i_sb)->s_es;
	283	es->s_last_error_block =
	284	cpu_to_le64(bh->b_blocknr);
c398eda0 TT	285	ext4_error_inode(inode, where, line,
	286	bh->b_blocknr,
	287	"IO error syncing itable block");
0390131b FM	288	err = -EIO;
	289	}
	290	}
	291	}
8984d137 AM	292	return err;
8984d137 AM	293	}
a0375156	294
90c7201b	295	int __ext4_handle_dirty_super(const char *where, unsigned int line,
b50924c2	296	handle_t handle, struct super_block sb)
a0375156 TT	297	{
	298	struct buffer_head *bh = EXT4_SB(sb)->s_sbh;
	299	int err = 0;
	300
06db49e6	301	ext4_superblock_csum_set(sb);
a0375156 TT	302	if (ext4_handle_valid(handle)) {
	303	err = jbd2_journal_dirty_metadata(handle, bh);
	304	if (err)
90c7201b TT	305	ext4_journal_abort_handle(where, line, __func__,
90c7201b TT	306	bh, handle, err);
06db49e6	307	} else
a9c47317	308	mark_buffer_dirty(bh);
a0375156 TT	309	return err;
a0375156 TT	310	}