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1// SPDX-License-Identifier: GPL-2.02/*3 * Interface between ext4 and JBD4 */5 6#include "ext4_jbd2.h"7 8#include <trace/events/ext4.h>9 10int ext4_inode_journal_mode(struct inode *inode)11{12	if (EXT4_JOURNAL(inode) == NULL)13		return EXT4_INODE_WRITEBACK_DATA_MODE;	/* writeback */14	/* We do not support data journalling with delayed allocation */15	if (!S_ISREG(inode->i_mode) ||16	    ext4_test_inode_flag(inode, EXT4_INODE_EA_INODE) ||17	    test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA ||18	    (ext4_test_inode_flag(inode, EXT4_INODE_JOURNAL_DATA) &&19	    !test_opt(inode->i_sb, DELALLOC))) {20		/* We do not support data journalling for encrypted data */21		if (S_ISREG(inode->i_mode) && IS_ENCRYPTED(inode))22			return EXT4_INODE_ORDERED_DATA_MODE;  /* ordered */23		return EXT4_INODE_JOURNAL_DATA_MODE;	/* journal data */24	}25	if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)26		return EXT4_INODE_ORDERED_DATA_MODE;	/* ordered */27	if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)28		return EXT4_INODE_WRITEBACK_DATA_MODE;	/* writeback */29	BUG();30}31 32/* Just increment the non-pointer handle value */33static handle_t *ext4_get_nojournal(void)34{35	handle_t *handle = current->journal_info;36	unsigned long ref_cnt = (unsigned long)handle;37 38	BUG_ON(ref_cnt >= EXT4_NOJOURNAL_MAX_REF_COUNT);39 40	ref_cnt++;41	handle = (handle_t *)ref_cnt;42 43	current->journal_info = handle;44	return handle;45}46 47 48/* Decrement the non-pointer handle value */49static void ext4_put_nojournal(handle_t *handle)50{51	unsigned long ref_cnt = (unsigned long)handle;52 53	BUG_ON(ref_cnt == 0);54 55	ref_cnt--;56	handle = (handle_t *)ref_cnt;57 58	current->journal_info = handle;59}60 61/*62 * Wrappers for jbd2_journal_start/end.63 */64static int ext4_journal_check_start(struct super_block *sb)65{66	journal_t *journal;67 68	might_sleep();69 70	if (unlikely(ext4_forced_shutdown(sb)))71		return -EIO;72 73	if (WARN_ON_ONCE(sb_rdonly(sb)))74		return -EROFS;75 76	WARN_ON(sb->s_writers.frozen == SB_FREEZE_COMPLETE);77	journal = EXT4_SB(sb)->s_journal;78	/*79	 * Special case here: if the journal has aborted behind our80	 * backs (eg. EIO in the commit thread), then we still need to81	 * take the FS itself readonly cleanly.82	 */83	if (journal && is_journal_aborted(journal)) {84		ext4_abort(sb, -journal->j_errno, "Detected aborted journal");85		return -EROFS;86	}87	return 0;88}89 90handle_t *__ext4_journal_start_sb(struct inode *inode,91				  struct super_block *sb, unsigned int line,92				  int type, int blocks, int rsv_blocks,93				  int revoke_creds)94{95	journal_t *journal;96	int err;97	if (inode)98		trace_ext4_journal_start_inode(inode, blocks, rsv_blocks,99					revoke_creds, type,100					_RET_IP_);101	else102		trace_ext4_journal_start_sb(sb, blocks, rsv_blocks,103					revoke_creds, type,104					_RET_IP_);105	err = ext4_journal_check_start(sb);106	if (err < 0)107		return ERR_PTR(err);108 109	journal = EXT4_SB(sb)->s_journal;110	if (!journal || (EXT4_SB(sb)->s_mount_state & EXT4_FC_REPLAY))111		return ext4_get_nojournal();112	return jbd2__journal_start(journal, blocks, rsv_blocks, revoke_creds,113				   GFP_NOFS, type, line);114}115 116int __ext4_journal_stop(const char *where, unsigned int line, handle_t *handle)117{118	struct super_block *sb;119	int err;120	int rc;121 122	if (!ext4_handle_valid(handle)) {123		ext4_put_nojournal(handle);124		return 0;125	}126 127	err = handle->h_err;128	if (!handle->h_transaction) {129		rc = jbd2_journal_stop(handle);130		return err ? err : rc;131	}132 133	sb = handle->h_transaction->t_journal->j_private;134	rc = jbd2_journal_stop(handle);135 136	if (!err)137		err = rc;138	if (err)139		__ext4_std_error(sb, where, line, err);140	return err;141}142 143handle_t *__ext4_journal_start_reserved(handle_t *handle, unsigned int line,144					int type)145{146	struct super_block *sb;147	int err;148 149	if (!ext4_handle_valid(handle))150		return ext4_get_nojournal();151 152	sb = handle->h_journal->j_private;153	trace_ext4_journal_start_reserved(sb,154				jbd2_handle_buffer_credits(handle), _RET_IP_);155	err = ext4_journal_check_start(sb);156	if (err < 0) {157		jbd2_journal_free_reserved(handle);158		return ERR_PTR(err);159	}160 161	err = jbd2_journal_start_reserved(handle, type, line);162	if (err < 0)163		return ERR_PTR(err);164	return handle;165}166 167int __ext4_journal_ensure_credits(handle_t *handle, int check_cred,168				  int extend_cred, int revoke_cred)169{170	if (!ext4_handle_valid(handle))171		return 0;172	if (is_handle_aborted(handle))173		return -EROFS;174	if (jbd2_handle_buffer_credits(handle) >= check_cred &&175	    handle->h_revoke_credits >= revoke_cred)176		return 0;177	extend_cred = max(0, extend_cred - jbd2_handle_buffer_credits(handle));178	revoke_cred = max(0, revoke_cred - handle->h_revoke_credits);179	return ext4_journal_extend(handle, extend_cred, revoke_cred);180}181 182static void ext4_journal_abort_handle(const char *caller, unsigned int line,183				      const char *err_fn,184				      struct buffer_head *bh,185				      handle_t *handle, int err)186{187	char nbuf[16];188	const char *errstr = ext4_decode_error(NULL, err, nbuf);189 190	BUG_ON(!ext4_handle_valid(handle));191 192	if (bh)193		BUFFER_TRACE(bh, "abort");194 195	if (!handle->h_err)196		handle->h_err = err;197 198	if (is_handle_aborted(handle))199		return;200 201	printk(KERN_ERR "EXT4-fs: %s:%d: aborting transaction: %s in %s\n",202	       caller, line, errstr, err_fn);203 204	jbd2_journal_abort_handle(handle);205}206 207static void ext4_check_bdev_write_error(struct super_block *sb)208{209	struct address_space *mapping = sb->s_bdev->bd_mapping;210	struct ext4_sb_info *sbi = EXT4_SB(sb);211	int err;212 213	/*214	 * If the block device has write error flag, it may have failed to215	 * async write out metadata buffers in the background. In this case,216	 * we could read old data from disk and write it out again, which217	 * may lead to on-disk filesystem inconsistency.218	 */219	if (errseq_check(&mapping->wb_err, READ_ONCE(sbi->s_bdev_wb_err))) {220		spin_lock(&sbi->s_bdev_wb_lock);221		err = errseq_check_and_advance(&mapping->wb_err, &sbi->s_bdev_wb_err);222		spin_unlock(&sbi->s_bdev_wb_lock);223		if (err)224			ext4_error_err(sb, -err,225				       "Error while async write back metadata");226	}227}228 229int __ext4_journal_get_write_access(const char *where, unsigned int line,230				    handle_t *handle, struct super_block *sb,231				    struct buffer_head *bh,232				    enum ext4_journal_trigger_type trigger_type)233{234	int err;235 236	might_sleep();237 238	if (ext4_handle_valid(handle)) {239		err = jbd2_journal_get_write_access(handle, bh);240		if (err) {241			ext4_journal_abort_handle(where, line, __func__, bh,242						  handle, err);243			return err;244		}245	} else246		ext4_check_bdev_write_error(sb);247	if (trigger_type == EXT4_JTR_NONE || !ext4_has_metadata_csum(sb))248		return 0;249	BUG_ON(trigger_type >= EXT4_JOURNAL_TRIGGER_COUNT);250	jbd2_journal_set_triggers(bh,251		&EXT4_SB(sb)->s_journal_triggers[trigger_type].tr_triggers);252	return 0;253}254 255/*256 * The ext4 forget function must perform a revoke if we are freeing data257 * which has been journaled.  Metadata (eg. indirect blocks) must be258 * revoked in all cases.259 *260 * "bh" may be NULL: a metadata block may have been freed from memory261 * but there may still be a record of it in the journal, and that record262 * still needs to be revoked.263 */264int __ext4_forget(const char *where, unsigned int line, handle_t *handle,265		  int is_metadata, struct inode *inode,266		  struct buffer_head *bh, ext4_fsblk_t blocknr)267{268	int err;269 270	might_sleep();271 272	trace_ext4_forget(inode, is_metadata, blocknr);273	BUFFER_TRACE(bh, "enter");274 275	ext4_debug("forgetting bh %p: is_metadata=%d, mode %o, data mode %x\n",276		  bh, is_metadata, inode->i_mode,277		  test_opt(inode->i_sb, DATA_FLAGS));278 279	/* In the no journal case, we can just do a bforget and return */280	if (!ext4_handle_valid(handle)) {281		bforget(bh);282		return 0;283	}284 285	/* Never use the revoke function if we are doing full data286	 * journaling: there is no need to, and a V1 superblock won't287	 * support it.  Otherwise, only skip the revoke on un-journaled288	 * data blocks. */289 290	if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA ||291	    (!is_metadata && !ext4_should_journal_data(inode))) {292		if (bh) {293			BUFFER_TRACE(bh, "call jbd2_journal_forget");294			err = jbd2_journal_forget(handle, bh);295			if (err)296				ext4_journal_abort_handle(where, line, __func__,297							  bh, handle, err);298			return err;299		}300		return 0;301	}302 303	/*304	 * data!=journal && (is_metadata || should_journal_data(inode))305	 */306	BUFFER_TRACE(bh, "call jbd2_journal_revoke");307	err = jbd2_journal_revoke(handle, blocknr, bh);308	if (err) {309		ext4_journal_abort_handle(where, line, __func__,310					  bh, handle, err);311		__ext4_error(inode->i_sb, where, line, true, -err, 0,312			     "error %d when attempting revoke", err);313	}314	BUFFER_TRACE(bh, "exit");315	return err;316}317 318int __ext4_journal_get_create_access(const char *where, unsigned int line,319				handle_t *handle, struct super_block *sb,320				struct buffer_head *bh,321				enum ext4_journal_trigger_type trigger_type)322{323	int err;324 325	if (!ext4_handle_valid(handle))326		return 0;327 328	err = jbd2_journal_get_create_access(handle, bh);329	if (err) {330		ext4_journal_abort_handle(where, line, __func__, bh, handle,331					  err);332		return err;333	}334	if (trigger_type == EXT4_JTR_NONE || !ext4_has_metadata_csum(sb))335		return 0;336	BUG_ON(trigger_type >= EXT4_JOURNAL_TRIGGER_COUNT);337	jbd2_journal_set_triggers(bh,338		&EXT4_SB(sb)->s_journal_triggers[trigger_type].tr_triggers);339	return 0;340}341 342int __ext4_handle_dirty_metadata(const char *where, unsigned int line,343				 handle_t *handle, struct inode *inode,344				 struct buffer_head *bh)345{346	int err = 0;347 348	might_sleep();349 350	set_buffer_meta(bh);351	set_buffer_prio(bh);352	set_buffer_uptodate(bh);353	if (ext4_handle_valid(handle)) {354		err = jbd2_journal_dirty_metadata(handle, bh);355		/* Errors can only happen due to aborted journal or a nasty bug */356		if (!is_handle_aborted(handle) && WARN_ON_ONCE(err)) {357			ext4_journal_abort_handle(where, line, __func__, bh,358						  handle, err);359			if (inode == NULL) {360				pr_err("EXT4: jbd2_journal_dirty_metadata "361				       "failed: handle type %u started at "362				       "line %u, credits %u/%u, errcode %d",363				       handle->h_type,364				       handle->h_line_no,365				       handle->h_requested_credits,366				       jbd2_handle_buffer_credits(handle), err);367				return err;368			}369			ext4_error_inode(inode, where, line,370					 bh->b_blocknr,371					 "journal_dirty_metadata failed: "372					 "handle type %u started at line %u, "373					 "credits %u/%u, errcode %d",374					 handle->h_type,375					 handle->h_line_no,376					 handle->h_requested_credits,377					 jbd2_handle_buffer_credits(handle),378					 err);379		}380	} else {381		if (inode)382			mark_buffer_dirty_inode(bh, inode);383		else384			mark_buffer_dirty(bh);385		if (inode && inode_needs_sync(inode)) {386			sync_dirty_buffer(bh);387			if (buffer_req(bh) && !buffer_uptodate(bh)) {388				ext4_error_inode_err(inode, where, line,389						     bh->b_blocknr, EIO,390					"IO error syncing itable block");391				err = -EIO;392			}393		}394	}395	return err;396}397