[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.
 */
handle_t *__ext4_journal_start_sb(struct super_block *sb, unsigned int line,
				  int type, int nblocks)
{
	journal_t *journal;

	might_sleep();

	trace_ext4_journal_start(sb, nblocks, _RET_IP_);
	if (sb->s_flags & MS_RDONLY)
		return ERR_PTR(-EROFS);

	WARN_ON(sb->s_writers.frozen == SB_FREEZE_COMPLETE);
	journal = EXT4_SB(sb)->s_journal;
	if (!journal)
		return ext4_get_nojournal();
	/*
	 * 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 (is_journal_aborted(journal)) {
		ext4_abort(sb, "Detected aborted journal");
		return ERR_PTR(-EROFS);
	}
	return jbd2__journal_start(journal, nblocks, 0, 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;
}

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);
		if (err) {
			/* Errors can only happen if there is a bug */
			handle->h_err = err;
			__ext4_journal_stop(where, line, handle);
		}
	} 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	*/
9924a92a TT	41	handle_t __ext4_journal_start_sb(struct super_block sb, unsigned int line,
9924a92a TT	42	int type, int nblocks)
722887dd TT	43	{
	44	journal_t *journal;
	45
b10a44c3 TT	46	might_sleep();
b10a44c3 TT	47
722887dd TT	48	trace_ext4_journal_start(sb, nblocks, _RET_IP_);
	49	if (sb->s_flags & MS_RDONLY)
	50	return ERR_PTR(-EROFS);
	51
	52	WARN_ON(sb->s_writers.frozen == SB_FREEZE_COMPLETE);
	53	journal = EXT4_SB(sb)->s_journal;
	54	if (!journal)
	55	return ext4_get_nojournal();
	56	/*
	57	* Special case here: if the journal has aborted behind our
	58	* backs (eg. EIO in the commit thread), then we still need to
	59	* take the FS itself readonly cleanly.
	60	*/
	61	if (is_journal_aborted(journal)) {
	62	ext4_abort(sb, "Detected aborted journal");
	63	return ERR_PTR(-EROFS);
	64	}
8f7d89f3	65	return jbd2__journal_start(journal, nblocks, 0, GFP_NOFS, type, line);
722887dd TT	66	}
	67
	68	int __ext4_journal_stop(const char where, unsigned int line, handle_t handle)
	69	{
	70	struct super_block *sb;
	71	int err;
	72	int rc;
	73
	74	if (!ext4_handle_valid(handle)) {
	75	ext4_put_nojournal(handle);
	76	return 0;
	77	}
	78	sb = handle->h_transaction->t_journal->j_private;
	79	err = handle->h_err;
	80	rc = jbd2_journal_stop(handle);
	81
	82	if (!err)
	83	err = rc;
	84	if (err)
	85	__ext4_std_error(sb, where, line, err);
	86	return err;
	87	}
	88
	89	void ext4_journal_abort_handle(const char *caller, unsigned int line,
	90	const char err_fn, struct buffer_head bh,
	91	handle_t *handle, int err)
	92	{
	93	char nbuf[16];
	94	const char *errstr = ext4_decode_error(NULL, err, nbuf);
	95
	96	BUG_ON(!ext4_handle_valid(handle));
	97
	98	if (bh)
	99	BUFFER_TRACE(bh, "abort");
	100
	101	if (!handle->h_err)
	102	handle->h_err = err;
	103
	104	if (is_handle_aborted(handle))
	105	return;
	106
	107	printk(KERN_ERR "EXT4-fs: %s:%d: aborting transaction: %s in %s\n",
	108	caller, line, errstr, err_fn);
	109
	110	jbd2_journal_abort_handle(handle);
	111	}
	112
90c7201b TT	113	int __ext4_journal_get_write_access(const char *where, unsigned int line,
90c7201b TT	114	handle_t handle, struct buffer_head bh)
8984d137	115	{
0390131b FM	116	int err = 0;
0390131b FM	117
b10a44c3 TT	118	might_sleep();
b10a44c3 TT	119
0390131b FM	120	if (ext4_handle_valid(handle)) {
	121	err = jbd2_journal_get_write_access(handle, bh);
	122	if (err)
90c7201b	123	ext4_journal_abort_handle(where, line, __func__, bh,
0390131b FM	124	handle, err);
0390131b FM	125	}
8984d137 AM	126	return err;
	127	}
	128
d6797d14 TT	129	/*
	130	* The ext4 forget function must perform a revoke if we are freeing data
	131	* which has been journaled. Metadata (eg. indirect blocks) must be
	132	* revoked in all cases.
	133	*
	134	* "bh" may be NULL: a metadata block may have been freed from memory
	135	* but there may still be a record of it in the journal, and that record
	136	* still needs to be revoked.
	137	*
	138	* If the handle isn't valid we're not journaling, but we still need to
	139	* call into ext4_journal_revoke() to put the buffer head.
	140	*/
90c7201b TT	141	int __ext4_forget(const char where, unsigned int line, handle_t handle,
	142	int is_metadata, struct inode *inode,
	143	struct buffer_head *bh, ext4_fsblk_t blocknr)
d6797d14 TT	144	{
	145	int err;
	146
	147	might_sleep();
	148
	149	trace_ext4_forget(inode, is_metadata, blocknr);
	150	BUFFER_TRACE(bh, "enter");
	151
	152	jbd_debug(4, "forgetting bh %p: is_metadata = %d, mode %o, "
	153	"data mode %x\n",
	154	bh, is_metadata, inode->i_mode,
	155	test_opt(inode->i_sb, DATA_FLAGS));
	156
e4684b3f TT	157	/* In the no journal case, we can just do a bforget and return */
	158	if (!ext4_handle_valid(handle)) {
	159	bforget(bh);
	160	return 0;
	161	}
	162
d6797d14 TT	163	/* Never use the revoke function if we are doing full data
	164	* journaling: there is no need to, and a V1 superblock won't
	165	* support it. Otherwise, only skip the revoke on un-journaled
	166	* data blocks. */
	167
	168	if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA \|\|
	169	(!is_metadata && !ext4_should_journal_data(inode))) {
	170	if (bh) {
	171	BUFFER_TRACE(bh, "call jbd2_journal_forget");
b7e57e7c TT	172	err = jbd2_journal_forget(handle, bh);
b7e57e7c TT	173	if (err)
90c7201b TT	174	ext4_journal_abort_handle(where, line, __func__,
90c7201b TT	175	bh, handle, err);
b7e57e7c	176	return err;
d6797d14 TT	177	}
	178	return 0;
	179	}
	180
	181	/*
	182	* data!=journal && (is_metadata \|\| should_journal_data(inode))
	183	*/
e4684b3f TT	184	BUFFER_TRACE(bh, "call jbd2_journal_revoke");
	185	err = jbd2_journal_revoke(handle, blocknr, bh);
	186	if (err) {
90c7201b TT	187	ext4_journal_abort_handle(where, line, __func__,
90c7201b TT	188	bh, handle, err);
c398eda0 TT	189	__ext4_abort(inode->i_sb, where, line,
c398eda0 TT	190	"error %d when attempting revoke", err);
e4684b3f	191	}
d6797d14 TT	192	BUFFER_TRACE(bh, "exit");
	193	return err;
	194	}
	195
90c7201b	196	int __ext4_journal_get_create_access(const char *where, unsigned int line,
8984d137 AM	197	handle_t handle, struct buffer_head bh)
8984d137 AM	198	{
0390131b FM	199	int err = 0;
	200
	201	if (ext4_handle_valid(handle)) {
	202	err = jbd2_journal_get_create_access(handle, bh);
	203	if (err)
90c7201b TT	204	ext4_journal_abort_handle(where, line, __func__,
90c7201b TT	205	bh, handle, err);
0390131b	206	}
8984d137 AM	207	return err;
	208	}
	209
90c7201b TT	210	int __ext4_handle_dirty_metadata(const char *where, unsigned int line,
	211	handle_t handle, struct inode inode,
	212	struct buffer_head *bh)
8984d137	213	{
0390131b FM	214	int err = 0;
0390131b FM	215
b10a44c3 TT	216	might_sleep();
b10a44c3 TT	217
13fca323 TT	218	set_buffer_meta(bh);
13fca323 TT	219	set_buffer_prio(bh);
0390131b FM	220	if (ext4_handle_valid(handle)) {
0390131b FM	221	err = jbd2_journal_dirty_metadata(handle, bh);
9ea7a0df TT	222	if (err) {
	223	/* Errors can only happen if there is a bug */
	224	handle->h_err = err;
	225	__ext4_journal_stop(where, line, handle);
	226	}
0390131b	227	} else {
73b50c1c	228	if (inode)
fe188c0e TT	229	mark_buffer_dirty_inode(bh, inode);
	230	else
	231	mark_buffer_dirty(bh);
0390131b FM	232	if (inode && inode_needs_sync(inode)) {
	233	sync_dirty_buffer(bh);
	234	if (buffer_req(bh) && !buffer_uptodate(bh)) {
1c13d5c0 TT	235	struct ext4_super_block *es;
	236
	237	es = EXT4_SB(inode->i_sb)->s_es;
	238	es->s_last_error_block =
	239	cpu_to_le64(bh->b_blocknr);
c398eda0 TT	240	ext4_error_inode(inode, where, line,
	241	bh->b_blocknr,
	242	"IO error syncing itable block");
0390131b FM	243	err = -EIO;
	244	}
	245	}
	246	}
8984d137 AM	247	return err;
8984d137 AM	248	}
a0375156	249
90c7201b	250	int __ext4_handle_dirty_super(const char *where, unsigned int line,
b50924c2	251	handle_t handle, struct super_block sb)
a0375156 TT	252	{
	253	struct buffer_head *bh = EXT4_SB(sb)->s_sbh;
	254	int err = 0;
	255
06db49e6	256	ext4_superblock_csum_set(sb);
a0375156 TT	257	if (ext4_handle_valid(handle)) {
	258	err = jbd2_journal_dirty_metadata(handle, bh);
	259	if (err)
90c7201b TT	260	ext4_journal_abort_handle(where, line, __func__,
90c7201b TT	261	bh, handle, err);
06db49e6	262	} else
a9c47317	263	mark_buffer_dirty(bh);
a0375156 TT	264	return err;
a0375156 TT	265	}